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bnx2x: remove ndo_poll_controller
[linux/fpc-iii.git] / fs / btrfs / inode.c
blob3ea5339603cff14f8dc103f6561091e83dc0b81a
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #include <linux/kernel.h>
7 #include <linux/bio.h>
8 #include <linux/buffer_head.h>
9 #include <linux/file.h>
10 #include <linux/fs.h>
11 #include <linux/pagemap.h>
12 #include <linux/highmem.h>
13 #include <linux/time.h>
14 #include <linux/init.h>
15 #include <linux/string.h>
16 #include <linux/backing-dev.h>
17 #include <linux/writeback.h>
18 #include <linux/compat.h>
19 #include <linux/xattr.h>
20 #include <linux/posix_acl.h>
21 #include <linux/falloc.h>
22 #include <linux/slab.h>
23 #include <linux/ratelimit.h>
24 #include <linux/btrfs.h>
25 #include <linux/blkdev.h>
26 #include <linux/posix_acl_xattr.h>
27 #include <linux/uio.h>
28 #include <linux/magic.h>
29 #include <linux/iversion.h>
30 #include <asm/unaligned.h>
31 #include "ctree.h"
32 #include "disk-io.h"
33 #include "transaction.h"
34 #include "btrfs_inode.h"
35 #include "print-tree.h"
36 #include "ordered-data.h"
37 #include "xattr.h"
38 #include "tree-log.h"
39 #include "volumes.h"
40 #include "compression.h"
41 #include "locking.h"
42 #include "free-space-cache.h"
43 #include "inode-map.h"
44 #include "backref.h"
45 #include "props.h"
46 #include "qgroup.h"
47 #include "dedupe.h"
48
49 struct btrfs_iget_args {
50 struct btrfs_key *location;
51 struct btrfs_root *root;
52 };
53
54 struct btrfs_dio_data {
55 u64 reserve;
56 u64 unsubmitted_oe_range_start;
57 u64 unsubmitted_oe_range_end;
58 int overwrite;
59 };
60
61 static const struct inode_operations btrfs_dir_inode_operations;
62 static const struct inode_operations btrfs_symlink_inode_operations;
63 static const struct inode_operations btrfs_dir_ro_inode_operations;
64 static const struct inode_operations btrfs_special_inode_operations;
65 static const struct inode_operations btrfs_file_inode_operations;
66 static const struct address_space_operations btrfs_aops;
67 static const struct address_space_operations btrfs_symlink_aops;
68 static const struct file_operations btrfs_dir_file_operations;
69 static const struct extent_io_ops btrfs_extent_io_ops;
70
71 static struct kmem_cache *btrfs_inode_cachep;
72 struct kmem_cache *btrfs_trans_handle_cachep;
73 struct kmem_cache *btrfs_path_cachep;
74 struct kmem_cache *btrfs_free_space_cachep;
75
76 #define S_SHIFT 12
77 static const unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
78 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
79 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
80 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
81 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
82 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
83 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
84 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
85 };
86
87 static int btrfs_setsize(struct inode *inode, struct iattr *attr);
88 static int btrfs_truncate(struct inode *inode, bool skip_writeback);
89 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent);
90 static noinline int cow_file_range(struct inode *inode,
91 struct page *locked_page,
92 u64 start, u64 end, u64 delalloc_end,
93 int *page_started, unsigned long *nr_written,
94 int unlock, struct btrfs_dedupe_hash *hash);
95 static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len,
96 u64 orig_start, u64 block_start,
97 u64 block_len, u64 orig_block_len,
98 u64 ram_bytes, int compress_type,
99 int type);
100
101 static void __endio_write_update_ordered(struct inode *inode,
102 const u64 offset, const u64 bytes,
103 const bool uptodate);
104
105 /*
106 * Cleanup all submitted ordered extents in specified range to handle errors
107 * from the fill_dellaloc() callback.
108 *
109 * NOTE: caller must ensure that when an error happens, it can not call
110 * extent_clear_unlock_delalloc() to clear both the bits EXTENT_DO_ACCOUNTING
111 * and EXTENT_DELALLOC simultaneously, because that causes the reserved metadata
112 * to be released, which we want to happen only when finishing the ordered
113 * extent (btrfs_finish_ordered_io()). Also note that the caller of the
114 * fill_delalloc() callback already does proper cleanup for the first page of
115 * the range, that is, it invokes the callback writepage_end_io_hook() for the
116 * range of the first page.
117 */
118 static inline void btrfs_cleanup_ordered_extents(struct inode *inode,
119 const u64 offset,
120 const u64 bytes)
121 {
122 unsigned long index = offset >> PAGE_SHIFT;
123 unsigned long end_index = (offset + bytes - 1) >> PAGE_SHIFT;
124 struct page *page;
125
126 while (index <= end_index) {
127 page = find_get_page(inode->i_mapping, index);
128 index++;
129 if (!page)
130 continue;
131 ClearPagePrivate2(page);
132 put_page(page);
133 }
134 return __endio_write_update_ordered(inode, offset + PAGE_SIZE,
135 bytes - PAGE_SIZE, false);
136 }
137
138 static int btrfs_dirty_inode(struct inode *inode);
139
140 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
141 void btrfs_test_inode_set_ops(struct inode *inode)
142 {
143 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
144 }
145 #endif
146
147 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
148 struct inode *inode, struct inode *dir,
149 const struct qstr *qstr)
150 {
151 int err;
152
153 err = btrfs_init_acl(trans, inode, dir);
154 if (!err)
155 err = btrfs_xattr_security_init(trans, inode, dir, qstr);
156 return err;
157 }
158
159 /*
160 * this does all the hard work for inserting an inline extent into
161 * the btree. The caller should have done a btrfs_drop_extents so that
162 * no overlapping inline items exist in the btree
163 */
164 static int insert_inline_extent(struct btrfs_trans_handle *trans,
165 struct btrfs_path *path, int extent_inserted,
166 struct btrfs_root *root, struct inode *inode,
167 u64 start, size_t size, size_t compressed_size,
168 int compress_type,
169 struct page **compressed_pages)
170 {
171 struct extent_buffer *leaf;
172 struct page *page = NULL;
173 char *kaddr;
174 unsigned long ptr;
175 struct btrfs_file_extent_item *ei;
176 int ret;
177 size_t cur_size = size;
178 unsigned long offset;
179
180 if (compressed_size && compressed_pages)
181 cur_size = compressed_size;
182
183 inode_add_bytes(inode, size);
184
185 if (!extent_inserted) {
186 struct btrfs_key key;
187 size_t datasize;
188
189 key.objectid = btrfs_ino(BTRFS_I(inode));
190 key.offset = start;
191 key.type = BTRFS_EXTENT_DATA_KEY;
192
193 datasize = btrfs_file_extent_calc_inline_size(cur_size);
194 path->leave_spinning = 1;
195 ret = btrfs_insert_empty_item(trans, root, path, &key,
196 datasize);
197 if (ret)
198 goto fail;
199 }
200 leaf = path->nodes[0];
201 ei = btrfs_item_ptr(leaf, path->slots[0],
202 struct btrfs_file_extent_item);
203 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
204 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
205 btrfs_set_file_extent_encryption(leaf, ei, 0);
206 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
207 btrfs_set_file_extent_ram_bytes(leaf, ei, size);
208 ptr = btrfs_file_extent_inline_start(ei);
209
210 if (compress_type != BTRFS_COMPRESS_NONE) {
211 struct page *cpage;
212 int i = 0;
213 while (compressed_size > 0) {
214 cpage = compressed_pages[i];
215 cur_size = min_t(unsigned long, compressed_size,
216 PAGE_SIZE);
217
218 kaddr = kmap_atomic(cpage);
219 write_extent_buffer(leaf, kaddr, ptr, cur_size);
220 kunmap_atomic(kaddr);
221
222 i++;
223 ptr += cur_size;
224 compressed_size -= cur_size;
225 }
226 btrfs_set_file_extent_compression(leaf, ei,
227 compress_type);
228 } else {
229 page = find_get_page(inode->i_mapping,
230 start >> PAGE_SHIFT);
231 btrfs_set_file_extent_compression(leaf, ei, 0);
232 kaddr = kmap_atomic(page);
233 offset = start & (PAGE_SIZE - 1);
234 write_extent_buffer(leaf, kaddr + offset, ptr, size);
235 kunmap_atomic(kaddr);
236 put_page(page);
237 }
238 btrfs_mark_buffer_dirty(leaf);
239 btrfs_release_path(path);
240
241 /*
242 * we're an inline extent, so nobody can
243 * extend the file past i_size without locking
244 * a page we already have locked.
245 *
246 * We must do any isize and inode updates
247 * before we unlock the pages. Otherwise we
248 * could end up racing with unlink.
249 */
250 BTRFS_I(inode)->disk_i_size = inode->i_size;
251 ret = btrfs_update_inode(trans, root, inode);
252
253 fail:
254 return ret;
255 }
256
257
258 /*
259 * conditionally insert an inline extent into the file. This
260 * does the checks required to make sure the data is small enough
261 * to fit as an inline extent.
262 */
263 static noinline int cow_file_range_inline(struct inode *inode, u64 start,
264 u64 end, size_t compressed_size,
265 int compress_type,
266 struct page **compressed_pages)
267 {
268 struct btrfs_root *root = BTRFS_I(inode)->root;
269 struct btrfs_fs_info *fs_info = root->fs_info;
270 struct btrfs_trans_handle *trans;
271 u64 isize = i_size_read(inode);
272 u64 actual_end = min(end + 1, isize);
273 u64 inline_len = actual_end - start;
274 u64 aligned_end = ALIGN(end, fs_info->sectorsize);
275 u64 data_len = inline_len;
276 int ret;
277 struct btrfs_path *path;
278 int extent_inserted = 0;
279 u32 extent_item_size;
280
281 if (compressed_size)
282 data_len = compressed_size;
283
284 if (start > 0 ||
285 actual_end > fs_info->sectorsize ||
286 data_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info) ||
287 (!compressed_size &&
288 (actual_end & (fs_info->sectorsize - 1)) == 0) ||
289 end + 1 < isize ||
290 data_len > fs_info->max_inline) {
291 return 1;
292 }
293
294 path = btrfs_alloc_path();
295 if (!path)
296 return -ENOMEM;
297
298 trans = btrfs_join_transaction(root);
299 if (IS_ERR(trans)) {
300 btrfs_free_path(path);
301 return PTR_ERR(trans);
302 }
303 trans->block_rsv = &BTRFS_I(inode)->block_rsv;
304
305 if (compressed_size && compressed_pages)
306 extent_item_size = btrfs_file_extent_calc_inline_size(
307 compressed_size);
308 else
309 extent_item_size = btrfs_file_extent_calc_inline_size(
310 inline_len);
311
312 ret = __btrfs_drop_extents(trans, root, inode, path,
313 start, aligned_end, NULL,
314 1, 1, extent_item_size, &extent_inserted);
315 if (ret) {
316 btrfs_abort_transaction(trans, ret);
317 goto out;
318 }
319
320 if (isize > actual_end)
321 inline_len = min_t(u64, isize, actual_end);
322 ret = insert_inline_extent(trans, path, extent_inserted,
323 root, inode, start,
324 inline_len, compressed_size,
325 compress_type, compressed_pages);
326 if (ret && ret != -ENOSPC) {
327 btrfs_abort_transaction(trans, ret);
328 goto out;
329 } else if (ret == -ENOSPC) {
330 ret = 1;
331 goto out;
332 }
333
334 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
335 btrfs_drop_extent_cache(BTRFS_I(inode), start, aligned_end - 1, 0);
336 out:
337 /*
338 * Don't forget to free the reserved space, as for inlined extent
339 * it won't count as data extent, free them directly here.
340 * And at reserve time, it's always aligned to page size, so
341 * just free one page here.
342 */
343 btrfs_qgroup_free_data(inode, NULL, 0, PAGE_SIZE);
344 btrfs_free_path(path);
345 btrfs_end_transaction(trans);
346 return ret;
347 }
348
349 struct async_extent {
350 u64 start;
351 u64 ram_size;
352 u64 compressed_size;
353 struct page **pages;
354 unsigned long nr_pages;
355 int compress_type;
356 struct list_head list;
357 };
358
359 struct async_cow {
360 struct inode *inode;
361 struct btrfs_root *root;
362 struct page *locked_page;
363 u64 start;
364 u64 end;
365 unsigned int write_flags;
366 struct list_head extents;
367 struct btrfs_work work;
368 };
369
370 static noinline int add_async_extent(struct async_cow *cow,
371 u64 start, u64 ram_size,
372 u64 compressed_size,
373 struct page **pages,
374 unsigned long nr_pages,
375 int compress_type)
376 {
377 struct async_extent *async_extent;
378
379 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
380 BUG_ON(!async_extent); /* -ENOMEM */
381 async_extent->start = start;
382 async_extent->ram_size = ram_size;
383 async_extent->compressed_size = compressed_size;
384 async_extent->pages = pages;
385 async_extent->nr_pages = nr_pages;
386 async_extent->compress_type = compress_type;
387 list_add_tail(&async_extent->list, &cow->extents);
388 return 0;
389 }
390
391 static inline int inode_need_compress(struct inode *inode, u64 start, u64 end)
392 {
393 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
394
395 /* force compress */
396 if (btrfs_test_opt(fs_info, FORCE_COMPRESS))
397 return 1;
398 /* defrag ioctl */
399 if (BTRFS_I(inode)->defrag_compress)
400 return 1;
401 /* bad compression ratios */
402 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
403 return 0;
404 if (btrfs_test_opt(fs_info, COMPRESS) ||
405 BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS ||
406 BTRFS_I(inode)->prop_compress)
407 return btrfs_compress_heuristic(inode, start, end);
408 return 0;
409 }
410
411 static inline void inode_should_defrag(struct btrfs_inode *inode,
412 u64 start, u64 end, u64 num_bytes, u64 small_write)
413 {
414 /* If this is a small write inside eof, kick off a defrag */
415 if (num_bytes < small_write &&
416 (start > 0 || end + 1 < inode->disk_i_size))
417 btrfs_add_inode_defrag(NULL, inode);
418 }
419
420 /*
421 * we create compressed extents in two phases. The first
422 * phase compresses a range of pages that have already been
423 * locked (both pages and state bits are locked).
424 *
425 * This is done inside an ordered work queue, and the compression
426 * is spread across many cpus. The actual IO submission is step
427 * two, and the ordered work queue takes care of making sure that
428 * happens in the same order things were put onto the queue by
429 * writepages and friends.
430 *
431 * If this code finds it can't get good compression, it puts an
432 * entry onto the work queue to write the uncompressed bytes. This
433 * makes sure that both compressed inodes and uncompressed inodes
434 * are written in the same order that the flusher thread sent them
435 * down.
436 */
437 static noinline void compress_file_range(struct inode *inode,
438 struct page *locked_page,
439 u64 start, u64 end,
440 struct async_cow *async_cow,
441 int *num_added)
442 {
443 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
444 u64 blocksize = fs_info->sectorsize;
445 u64 actual_end;
446 u64 isize = i_size_read(inode);
447 int ret = 0;
448 struct page **pages = NULL;
449 unsigned long nr_pages;
450 unsigned long total_compressed = 0;
451 unsigned long total_in = 0;
452 int i;
453 int will_compress;
454 int compress_type = fs_info->compress_type;
455 int redirty = 0;
456
457 inode_should_defrag(BTRFS_I(inode), start, end, end - start + 1,
458 SZ_16K);
459
460 actual_end = min_t(u64, isize, end + 1);
461 again:
462 will_compress = 0;
463 nr_pages = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1;
464 BUILD_BUG_ON((BTRFS_MAX_COMPRESSED % PAGE_SIZE) != 0);
465 nr_pages = min_t(unsigned long, nr_pages,
466 BTRFS_MAX_COMPRESSED / PAGE_SIZE);
467
468 /*
469 * we don't want to send crud past the end of i_size through
470 * compression, that's just a waste of CPU time. So, if the
471 * end of the file is before the start of our current
472 * requested range of bytes, we bail out to the uncompressed
473 * cleanup code that can deal with all of this.
474 *
475 * It isn't really the fastest way to fix things, but this is a
476 * very uncommon corner.
477 */
478 if (actual_end <= start)
479 goto cleanup_and_bail_uncompressed;
480
481 total_compressed = actual_end - start;
482
483 /*
484 * skip compression for a small file range(<=blocksize) that
485 * isn't an inline extent, since it doesn't save disk space at all.
486 */
487 if (total_compressed <= blocksize &&
488 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
489 goto cleanup_and_bail_uncompressed;
490
491 total_compressed = min_t(unsigned long, total_compressed,
492 BTRFS_MAX_UNCOMPRESSED);
493 total_in = 0;
494 ret = 0;
495
496 /*
497 * we do compression for mount -o compress and when the
498 * inode has not been flagged as nocompress. This flag can
499 * change at any time if we discover bad compression ratios.
500 */
501 if (inode_need_compress(inode, start, end)) {
502 WARN_ON(pages);
503 pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS);
504 if (!pages) {
505 /* just bail out to the uncompressed code */
506 goto cont;
507 }
508
509 if (BTRFS_I(inode)->defrag_compress)
510 compress_type = BTRFS_I(inode)->defrag_compress;
511 else if (BTRFS_I(inode)->prop_compress)
512 compress_type = BTRFS_I(inode)->prop_compress;
513
514 /*
515 * we need to call clear_page_dirty_for_io on each
516 * page in the range. Otherwise applications with the file
517 * mmap'd can wander in and change the page contents while
518 * we are compressing them.
519 *
520 * If the compression fails for any reason, we set the pages
521 * dirty again later on.
522 *
523 * Note that the remaining part is redirtied, the start pointer
524 * has moved, the end is the original one.
525 */
526 if (!redirty) {
527 extent_range_clear_dirty_for_io(inode, start, end);
528 redirty = 1;
529 }
530
531 /* Compression level is applied here and only here */
532 ret = btrfs_compress_pages(
533 compress_type | (fs_info->compress_level << 4),
534 inode->i_mapping, start,
535 pages,
536 &nr_pages,
537 &total_in,
538 &total_compressed);
539
540 if (!ret) {
541 unsigned long offset = total_compressed &
542 (PAGE_SIZE - 1);
543 struct page *page = pages[nr_pages - 1];
544 char *kaddr;
545
546 /* zero the tail end of the last page, we might be
547 * sending it down to disk
548 */
549 if (offset) {
550 kaddr = kmap_atomic(page);
551 memset(kaddr + offset, 0,
552 PAGE_SIZE - offset);
553 kunmap_atomic(kaddr);
554 }
555 will_compress = 1;
556 }
557 }
558 cont:
559 if (start == 0) {
560 /* lets try to make an inline extent */
561 if (ret || total_in < actual_end) {
562 /* we didn't compress the entire range, try
563 * to make an uncompressed inline extent.
564 */
565 ret = cow_file_range_inline(inode, start, end, 0,
566 BTRFS_COMPRESS_NONE, NULL);
567 } else {
568 /* try making a compressed inline extent */
569 ret = cow_file_range_inline(inode, start, end,
570 total_compressed,
571 compress_type, pages);
572 }
573 if (ret <= 0) {
574 unsigned long clear_flags = EXTENT_DELALLOC |
575 EXTENT_DELALLOC_NEW | EXTENT_DEFRAG |
576 EXTENT_DO_ACCOUNTING;
577 unsigned long page_error_op;
578
579 page_error_op = ret < 0 ? PAGE_SET_ERROR : 0;
580
581 /*
582 * inline extent creation worked or returned error,
583 * we don't need to create any more async work items.
584 * Unlock and free up our temp pages.
585 *
586 * We use DO_ACCOUNTING here because we need the
587 * delalloc_release_metadata to be done _after_ we drop
588 * our outstanding extent for clearing delalloc for this
589 * range.
590 */
591 extent_clear_unlock_delalloc(inode, start, end, end,
592 NULL, clear_flags,
593 PAGE_UNLOCK |
594 PAGE_CLEAR_DIRTY |
595 PAGE_SET_WRITEBACK |
596 page_error_op |
597 PAGE_END_WRITEBACK);
598 goto free_pages_out;
599 }
600 }
601
602 if (will_compress) {
603 /*
604 * we aren't doing an inline extent round the compressed size
605 * up to a block size boundary so the allocator does sane
606 * things
607 */
608 total_compressed = ALIGN(total_compressed, blocksize);
609
610 /*
611 * one last check to make sure the compression is really a
612 * win, compare the page count read with the blocks on disk,
613 * compression must free at least one sector size
614 */
615 total_in = ALIGN(total_in, PAGE_SIZE);
616 if (total_compressed + blocksize <= total_in) {
617 *num_added += 1;
618
619 /*
620 * The async work queues will take care of doing actual
621 * allocation on disk for these compressed pages, and
622 * will submit them to the elevator.
623 */
624 add_async_extent(async_cow, start, total_in,
625 total_compressed, pages, nr_pages,
626 compress_type);
627
628 if (start + total_in < end) {
629 start += total_in;
630 pages = NULL;
631 cond_resched();
632 goto again;
633 }
634 return;
635 }
636 }
637 if (pages) {
638 /*
639 * the compression code ran but failed to make things smaller,
640 * free any pages it allocated and our page pointer array
641 */
642 for (i = 0; i < nr_pages; i++) {
643 WARN_ON(pages[i]->mapping);
644 put_page(pages[i]);
645 }
646 kfree(pages);
647 pages = NULL;
648 total_compressed = 0;
649 nr_pages = 0;
650
651 /* flag the file so we don't compress in the future */
652 if (!btrfs_test_opt(fs_info, FORCE_COMPRESS) &&
653 !(BTRFS_I(inode)->prop_compress)) {
654 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
655 }
656 }
657 cleanup_and_bail_uncompressed:
658 /*
659 * No compression, but we still need to write the pages in the file
660 * we've been given so far. redirty the locked page if it corresponds
661 * to our extent and set things up for the async work queue to run
662 * cow_file_range to do the normal delalloc dance.
663 */
664 if (page_offset(locked_page) >= start &&
665 page_offset(locked_page) <= end)
666 __set_page_dirty_nobuffers(locked_page);
667 /* unlocked later on in the async handlers */
668
669 if (redirty)
670 extent_range_redirty_for_io(inode, start, end);
671 add_async_extent(async_cow, start, end - start + 1, 0, NULL, 0,
672 BTRFS_COMPRESS_NONE);
673 *num_added += 1;
674
675 return;
676
677 free_pages_out:
678 for (i = 0; i < nr_pages; i++) {
679 WARN_ON(pages[i]->mapping);
680 put_page(pages[i]);
681 }
682 kfree(pages);
683 }
684
685 static void free_async_extent_pages(struct async_extent *async_extent)
686 {
687 int i;
688
689 if (!async_extent->pages)
690 return;
691
692 for (i = 0; i < async_extent->nr_pages; i++) {
693 WARN_ON(async_extent->pages[i]->mapping);
694 put_page(async_extent->pages[i]);
695 }
696 kfree(async_extent->pages);
697 async_extent->nr_pages = 0;
698 async_extent->pages = NULL;
699 }
700
701 /*
702 * phase two of compressed writeback. This is the ordered portion
703 * of the code, which only gets called in the order the work was
704 * queued. We walk all the async extents created by compress_file_range
705 * and send them down to the disk.
706 */
707 static noinline void submit_compressed_extents(struct inode *inode,
708 struct async_cow *async_cow)
709 {
710 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
711 struct async_extent *async_extent;
712 u64 alloc_hint = 0;
713 struct btrfs_key ins;
714 struct extent_map *em;
715 struct btrfs_root *root = BTRFS_I(inode)->root;
716 struct extent_io_tree *io_tree;
717 int ret = 0;
718
719 again:
720 while (!list_empty(&async_cow->extents)) {
721 async_extent = list_entry(async_cow->extents.next,
722 struct async_extent, list);
723 list_del(&async_extent->list);
724
725 io_tree = &BTRFS_I(inode)->io_tree;
726
727 retry:
728 /* did the compression code fall back to uncompressed IO? */
729 if (!async_extent->pages) {
730 int page_started = 0;
731 unsigned long nr_written = 0;
732
733 lock_extent(io_tree, async_extent->start,
734 async_extent->start +
735 async_extent->ram_size - 1);
736
737 /* allocate blocks */
738 ret = cow_file_range(inode, async_cow->locked_page,
739 async_extent->start,
740 async_extent->start +
741 async_extent->ram_size - 1,
742 async_extent->start +
743 async_extent->ram_size - 1,
744 &page_started, &nr_written, 0,
745 NULL);
746
747 /* JDM XXX */
748
749 /*
750 * if page_started, cow_file_range inserted an
751 * inline extent and took care of all the unlocking
752 * and IO for us. Otherwise, we need to submit
753 * all those pages down to the drive.
754 */
755 if (!page_started && !ret)
756 extent_write_locked_range(inode,
757 async_extent->start,
758 async_extent->start +
759 async_extent->ram_size - 1,
760 WB_SYNC_ALL);
761 else if (ret)
762 unlock_page(async_cow->locked_page);
763 kfree(async_extent);
764 cond_resched();
765 continue;
766 }
767
768 lock_extent(io_tree, async_extent->start,
769 async_extent->start + async_extent->ram_size - 1);
770
771 ret = btrfs_reserve_extent(root, async_extent->ram_size,
772 async_extent->compressed_size,
773 async_extent->compressed_size,
774 0, alloc_hint, &ins, 1, 1);
775 if (ret) {
776 free_async_extent_pages(async_extent);
777
778 if (ret == -ENOSPC) {
779 unlock_extent(io_tree, async_extent->start,
780 async_extent->start +
781 async_extent->ram_size - 1);
782
783 /*
784 * we need to redirty the pages if we decide to
785 * fallback to uncompressed IO, otherwise we
786 * will not submit these pages down to lower
787 * layers.
788 */
789 extent_range_redirty_for_io(inode,
790 async_extent->start,
791 async_extent->start +
792 async_extent->ram_size - 1);
793
794 goto retry;
795 }
796 goto out_free;
797 }
798 /*
799 * here we're doing allocation and writeback of the
800 * compressed pages
801 */
802 em = create_io_em(inode, async_extent->start,
803 async_extent->ram_size, /* len */
804 async_extent->start, /* orig_start */
805 ins.objectid, /* block_start */
806 ins.offset, /* block_len */
807 ins.offset, /* orig_block_len */
808 async_extent->ram_size, /* ram_bytes */
809 async_extent->compress_type,
810 BTRFS_ORDERED_COMPRESSED);
811 if (IS_ERR(em))
812 /* ret value is not necessary due to void function */
813 goto out_free_reserve;
814 free_extent_map(em);
815
816 ret = btrfs_add_ordered_extent_compress(inode,
817 async_extent->start,
818 ins.objectid,
819 async_extent->ram_size,
820 ins.offset,
821 BTRFS_ORDERED_COMPRESSED,
822 async_extent->compress_type);
823 if (ret) {
824 btrfs_drop_extent_cache(BTRFS_I(inode),
825 async_extent->start,
826 async_extent->start +
827 async_extent->ram_size - 1, 0);
828 goto out_free_reserve;
829 }
830 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
831
832 /*
833 * clear dirty, set writeback and unlock the pages.
834 */
835 extent_clear_unlock_delalloc(inode, async_extent->start,
836 async_extent->start +
837 async_extent->ram_size - 1,
838 async_extent->start +
839 async_extent->ram_size - 1,
840 NULL, EXTENT_LOCKED | EXTENT_DELALLOC,
841 PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
842 PAGE_SET_WRITEBACK);
843 if (btrfs_submit_compressed_write(inode,
844 async_extent->start,
845 async_extent->ram_size,
846 ins.objectid,
847 ins.offset, async_extent->pages,
848 async_extent->nr_pages,
849 async_cow->write_flags)) {
850 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
851 struct page *p = async_extent->pages[0];
852 const u64 start = async_extent->start;
853 const u64 end = start + async_extent->ram_size - 1;
854
855 p->mapping = inode->i_mapping;
856 tree->ops->writepage_end_io_hook(p, start, end,
857 NULL, 0);
858 p->mapping = NULL;
859 extent_clear_unlock_delalloc(inode, start, end, end,
860 NULL, 0,
861 PAGE_END_WRITEBACK |
862 PAGE_SET_ERROR);
863 free_async_extent_pages(async_extent);
864 }
865 alloc_hint = ins.objectid + ins.offset;
866 kfree(async_extent);
867 cond_resched();
868 }
869 return;
870 out_free_reserve:
871 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
872 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1);
873 out_free:
874 extent_clear_unlock_delalloc(inode, async_extent->start,
875 async_extent->start +
876 async_extent->ram_size - 1,
877 async_extent->start +
878 async_extent->ram_size - 1,
879 NULL, EXTENT_LOCKED | EXTENT_DELALLOC |
880 EXTENT_DELALLOC_NEW |
881 EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING,
882 PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
883 PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK |
884 PAGE_SET_ERROR);
885 free_async_extent_pages(async_extent);
886 kfree(async_extent);
887 goto again;
888 }
889
890 static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
891 u64 num_bytes)
892 {
893 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
894 struct extent_map *em;
895 u64 alloc_hint = 0;
896
897 read_lock(&em_tree->lock);
898 em = search_extent_mapping(em_tree, start, num_bytes);
899 if (em) {
900 /*
901 * if block start isn't an actual block number then find the
902 * first block in this inode and use that as a hint. If that
903 * block is also bogus then just don't worry about it.
904 */
905 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
906 free_extent_map(em);
907 em = search_extent_mapping(em_tree, 0, 0);
908 if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
909 alloc_hint = em->block_start;
910 if (em)
911 free_extent_map(em);
912 } else {
913 alloc_hint = em->block_start;
914 free_extent_map(em);
915 }
916 }
917 read_unlock(&em_tree->lock);
918
919 return alloc_hint;
920 }
921
922 /*
923 * when extent_io.c finds a delayed allocation range in the file,
924 * the call backs end up in this code. The basic idea is to
925 * allocate extents on disk for the range, and create ordered data structs
926 * in ram to track those extents.
927 *
928 * locked_page is the page that writepage had locked already. We use
929 * it to make sure we don't do extra locks or unlocks.
930 *
931 * *page_started is set to one if we unlock locked_page and do everything
932 * required to start IO on it. It may be clean and already done with
933 * IO when we return.
934 */
935 static noinline int cow_file_range(struct inode *inode,
936 struct page *locked_page,
937 u64 start, u64 end, u64 delalloc_end,
938 int *page_started, unsigned long *nr_written,
939 int unlock, struct btrfs_dedupe_hash *hash)
940 {
941 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
942 struct btrfs_root *root = BTRFS_I(inode)->root;
943 u64 alloc_hint = 0;
944 u64 num_bytes;
945 unsigned long ram_size;
946 u64 cur_alloc_size = 0;
947 u64 blocksize = fs_info->sectorsize;
948 struct btrfs_key ins;
949 struct extent_map *em;
950 unsigned clear_bits;
951 unsigned long page_ops;
952 bool extent_reserved = false;
953 int ret = 0;
954
955 if (btrfs_is_free_space_inode(BTRFS_I(inode))) {
956 WARN_ON_ONCE(1);
957 ret = -EINVAL;
958 goto out_unlock;
959 }
960
961 num_bytes = ALIGN(end - start + 1, blocksize);
962 num_bytes = max(blocksize, num_bytes);
963 ASSERT(num_bytes <= btrfs_super_total_bytes(fs_info->super_copy));
964
965 inode_should_defrag(BTRFS_I(inode), start, end, num_bytes, SZ_64K);
966
967 if (start == 0) {
968 /* lets try to make an inline extent */
969 ret = cow_file_range_inline(inode, start, end, 0,
970 BTRFS_COMPRESS_NONE, NULL);
971 if (ret == 0) {
972 /*
973 * We use DO_ACCOUNTING here because we need the
974 * delalloc_release_metadata to be run _after_ we drop
975 * our outstanding extent for clearing delalloc for this
976 * range.
977 */
978 extent_clear_unlock_delalloc(inode, start, end,
979 delalloc_end, NULL,
980 EXTENT_LOCKED | EXTENT_DELALLOC |
981 EXTENT_DELALLOC_NEW | EXTENT_DEFRAG |
982 EXTENT_DO_ACCOUNTING, PAGE_UNLOCK |
983 PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK |
984 PAGE_END_WRITEBACK);
985 *nr_written = *nr_written +
986 (end - start + PAGE_SIZE) / PAGE_SIZE;
987 *page_started = 1;
988 goto out;
989 } else if (ret < 0) {
990 goto out_unlock;
991 }
992 }
993
994 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
995 btrfs_drop_extent_cache(BTRFS_I(inode), start,
996 start + num_bytes - 1, 0);
997
998 while (num_bytes > 0) {
999 cur_alloc_size = num_bytes;
1000 ret = btrfs_reserve_extent(root, cur_alloc_size, cur_alloc_size,
1001 fs_info->sectorsize, 0, alloc_hint,
1002 &ins, 1, 1);
1003 if (ret < 0)
1004 goto out_unlock;
1005 cur_alloc_size = ins.offset;
1006 extent_reserved = true;
1007
1008 ram_size = ins.offset;
1009 em = create_io_em(inode, start, ins.offset, /* len */
1010 start, /* orig_start */
1011 ins.objectid, /* block_start */
1012 ins.offset, /* block_len */
1013 ins.offset, /* orig_block_len */
1014 ram_size, /* ram_bytes */
1015 BTRFS_COMPRESS_NONE, /* compress_type */
1016 BTRFS_ORDERED_REGULAR /* type */);
1017 if (IS_ERR(em)) {
1018 ret = PTR_ERR(em);
1019 goto out_reserve;
1020 }
1021 free_extent_map(em);
1022
1023 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
1024 ram_size, cur_alloc_size, 0);
1025 if (ret)
1026 goto out_drop_extent_cache;
1027
1028 if (root->root_key.objectid ==
1029 BTRFS_DATA_RELOC_TREE_OBJECTID) {
1030 ret = btrfs_reloc_clone_csums(inode, start,
1031 cur_alloc_size);
1032 /*
1033 * Only drop cache here, and process as normal.
1034 *
1035 * We must not allow extent_clear_unlock_delalloc()
1036 * at out_unlock label to free meta of this ordered
1037 * extent, as its meta should be freed by
1038 * btrfs_finish_ordered_io().
1039 *
1040 * So we must continue until @start is increased to
1041 * skip current ordered extent.
1042 */
1043 if (ret)
1044 btrfs_drop_extent_cache(BTRFS_I(inode), start,
1045 start + ram_size - 1, 0);
1046 }
1047
1048 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
1049
1050 /* we're not doing compressed IO, don't unlock the first
1051 * page (which the caller expects to stay locked), don't
1052 * clear any dirty bits and don't set any writeback bits
1053 *
1054 * Do set the Private2 bit so we know this page was properly
1055 * setup for writepage
1056 */
1057 page_ops = unlock ? PAGE_UNLOCK : 0;
1058 page_ops |= PAGE_SET_PRIVATE2;
1059
1060 extent_clear_unlock_delalloc(inode, start,
1061 start + ram_size - 1,
1062 delalloc_end, locked_page,
1063 EXTENT_LOCKED | EXTENT_DELALLOC,
1064 page_ops);
1065 if (num_bytes < cur_alloc_size)
1066 num_bytes = 0;
1067 else
1068 num_bytes -= cur_alloc_size;
1069 alloc_hint = ins.objectid + ins.offset;
1070 start += cur_alloc_size;
1071 extent_reserved = false;
1072
1073 /*
1074 * btrfs_reloc_clone_csums() error, since start is increased
1075 * extent_clear_unlock_delalloc() at out_unlock label won't
1076 * free metadata of current ordered extent, we're OK to exit.
1077 */
1078 if (ret)
1079 goto out_unlock;
1080 }
1081 out:
1082 return ret;
1083
1084 out_drop_extent_cache:
1085 btrfs_drop_extent_cache(BTRFS_I(inode), start, start + ram_size - 1, 0);
1086 out_reserve:
1087 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
1088 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1);
1089 out_unlock:
1090 clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW |
1091 EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV;
1092 page_ops = PAGE_UNLOCK | PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK |
1093 PAGE_END_WRITEBACK;
1094 /*
1095 * If we reserved an extent for our delalloc range (or a subrange) and
1096 * failed to create the respective ordered extent, then it means that
1097 * when we reserved the extent we decremented the extent's size from
1098 * the data space_info's bytes_may_use counter and incremented the
1099 * space_info's bytes_reserved counter by the same amount. We must make
1100 * sure extent_clear_unlock_delalloc() does not try to decrement again
1101 * the data space_info's bytes_may_use counter, therefore we do not pass
1102 * it the flag EXTENT_CLEAR_DATA_RESV.
1103 */
1104 if (extent_reserved) {
1105 extent_clear_unlock_delalloc(inode, start,
1106 start + cur_alloc_size,
1107 start + cur_alloc_size,
1108 locked_page,
1109 clear_bits,
1110 page_ops);
1111 start += cur_alloc_size;
1112 if (start >= end)
1113 goto out;
1114 }
1115 extent_clear_unlock_delalloc(inode, start, end, delalloc_end,
1116 locked_page,
1117 clear_bits | EXTENT_CLEAR_DATA_RESV,
1118 page_ops);
1119 goto out;
1120 }
1121
1122 /*
1123 * work queue call back to started compression on a file and pages
1124 */
1125 static noinline void async_cow_start(struct btrfs_work *work)
1126 {
1127 struct async_cow *async_cow;
1128 int num_added = 0;
1129 async_cow = container_of(work, struct async_cow, work);
1130
1131 compress_file_range(async_cow->inode, async_cow->locked_page,
1132 async_cow->start, async_cow->end, async_cow,
1133 &num_added);
1134 if (num_added == 0) {
1135 btrfs_add_delayed_iput(async_cow->inode);
1136 async_cow->inode = NULL;
1137 }
1138 }
1139
1140 /*
1141 * work queue call back to submit previously compressed pages
1142 */
1143 static noinline void async_cow_submit(struct btrfs_work *work)
1144 {
1145 struct btrfs_fs_info *fs_info;
1146 struct async_cow *async_cow;
1147 struct btrfs_root *root;
1148 unsigned long nr_pages;
1149
1150 async_cow = container_of(work, struct async_cow, work);
1151
1152 root = async_cow->root;
1153 fs_info = root->fs_info;
1154 nr_pages = (async_cow->end - async_cow->start + PAGE_SIZE) >>
1155 PAGE_SHIFT;
1156
1157 /* atomic_sub_return implies a barrier */
1158 if (atomic_sub_return(nr_pages, &fs_info->async_delalloc_pages) <
1159 5 * SZ_1M)
1160 cond_wake_up_nomb(&fs_info->async_submit_wait);
1161
1162 if (async_cow->inode)
1163 submit_compressed_extents(async_cow->inode, async_cow);
1164 }
1165
1166 static noinline void async_cow_free(struct btrfs_work *work)
1167 {
1168 struct async_cow *async_cow;
1169 async_cow = container_of(work, struct async_cow, work);
1170 if (async_cow->inode)
1171 btrfs_add_delayed_iput(async_cow->inode);
1172 kfree(async_cow);
1173 }
1174
1175 static int cow_file_range_async(struct inode *inode, struct page *locked_page,
1176 u64 start, u64 end, int *page_started,
1177 unsigned long *nr_written,
1178 unsigned int write_flags)
1179 {
1180 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1181 struct async_cow *async_cow;
1182 struct btrfs_root *root = BTRFS_I(inode)->root;
1183 unsigned long nr_pages;
1184 u64 cur_end;
1185
1186 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
1187 1, 0, NULL);
1188 while (start < end) {
1189 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
1190 BUG_ON(!async_cow); /* -ENOMEM */
1191 async_cow->inode = igrab(inode);
1192 async_cow->root = root;
1193 async_cow->locked_page = locked_page;
1194 async_cow->start = start;
1195 async_cow->write_flags = write_flags;
1196
1197 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS &&
1198 !btrfs_test_opt(fs_info, FORCE_COMPRESS))
1199 cur_end = end;
1200 else
1201 cur_end = min(end, start + SZ_512K - 1);
1202
1203 async_cow->end = cur_end;
1204 INIT_LIST_HEAD(&async_cow->extents);
1205
1206 btrfs_init_work(&async_cow->work,
1207 btrfs_delalloc_helper,
1208 async_cow_start, async_cow_submit,
1209 async_cow_free);
1210
1211 nr_pages = (cur_end - start + PAGE_SIZE) >>
1212 PAGE_SHIFT;
1213 atomic_add(nr_pages, &fs_info->async_delalloc_pages);
1214
1215 btrfs_queue_work(fs_info->delalloc_workers, &async_cow->work);
1216
1217 *nr_written += nr_pages;
1218 start = cur_end + 1;
1219 }
1220 *page_started = 1;
1221 return 0;
1222 }
1223
1224 static noinline int csum_exist_in_range(struct btrfs_fs_info *fs_info,
1225 u64 bytenr, u64 num_bytes)
1226 {
1227 int ret;
1228 struct btrfs_ordered_sum *sums;
1229 LIST_HEAD(list);
1230
1231 ret = btrfs_lookup_csums_range(fs_info->csum_root, bytenr,
1232 bytenr + num_bytes - 1, &list, 0);
1233 if (ret == 0 && list_empty(&list))
1234 return 0;
1235
1236 while (!list_empty(&list)) {
1237 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
1238 list_del(&sums->list);
1239 kfree(sums);
1240 }
1241 if (ret < 0)
1242 return ret;
1243 return 1;
1244 }
1245
1246 /*
1247 * when nowcow writeback call back. This checks for snapshots or COW copies
1248 * of the extents that exist in the file, and COWs the file as required.
1249 *
1250 * If no cow copies or snapshots exist, we write directly to the existing
1251 * blocks on disk
1252 */
1253 static noinline int run_delalloc_nocow(struct inode *inode,
1254 struct page *locked_page,
1255 u64 start, u64 end, int *page_started, int force,
1256 unsigned long *nr_written)
1257 {
1258 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1259 struct btrfs_root *root = BTRFS_I(inode)->root;
1260 struct extent_buffer *leaf;
1261 struct btrfs_path *path;
1262 struct btrfs_file_extent_item *fi;
1263 struct btrfs_key found_key;
1264 struct extent_map *em;
1265 u64 cow_start;
1266 u64 cur_offset;
1267 u64 extent_end;
1268 u64 extent_offset;
1269 u64 disk_bytenr;
1270 u64 num_bytes;
1271 u64 disk_num_bytes;
1272 u64 ram_bytes;
1273 int extent_type;
1274 int ret;
1275 int type;
1276 int nocow;
1277 int check_prev = 1;
1278 bool nolock;
1279 u64 ino = btrfs_ino(BTRFS_I(inode));
1280
1281 path = btrfs_alloc_path();
1282 if (!path) {
1283 extent_clear_unlock_delalloc(inode, start, end, end,
1284 locked_page,
1285 EXTENT_LOCKED | EXTENT_DELALLOC |
1286 EXTENT_DO_ACCOUNTING |
1287 EXTENT_DEFRAG, PAGE_UNLOCK |
1288 PAGE_CLEAR_DIRTY |
1289 PAGE_SET_WRITEBACK |
1290 PAGE_END_WRITEBACK);
1291 return -ENOMEM;
1292 }
1293
1294 nolock = btrfs_is_free_space_inode(BTRFS_I(inode));
1295
1296 cow_start = (u64)-1;
1297 cur_offset = start;
1298 while (1) {
1299 ret = btrfs_lookup_file_extent(NULL, root, path, ino,
1300 cur_offset, 0);
1301 if (ret < 0)
1302 goto error;
1303 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1304 leaf = path->nodes[0];
1305 btrfs_item_key_to_cpu(leaf, &found_key,
1306 path->slots[0] - 1);
1307 if (found_key.objectid == ino &&
1308 found_key.type == BTRFS_EXTENT_DATA_KEY)
1309 path->slots[0]--;
1310 }
1311 check_prev = 0;
1312 next_slot:
1313 leaf = path->nodes[0];
1314 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1315 ret = btrfs_next_leaf(root, path);
1316 if (ret < 0) {
1317 if (cow_start != (u64)-1)
1318 cur_offset = cow_start;
1319 goto error;
1320 }
1321 if (ret > 0)
1322 break;
1323 leaf = path->nodes[0];
1324 }
1325
1326 nocow = 0;
1327 disk_bytenr = 0;
1328 num_bytes = 0;
1329 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1330
1331 if (found_key.objectid > ino)
1332 break;
1333 if (WARN_ON_ONCE(found_key.objectid < ino) ||
1334 found_key.type < BTRFS_EXTENT_DATA_KEY) {
1335 path->slots[0]++;
1336 goto next_slot;
1337 }
1338 if (found_key.type > BTRFS_EXTENT_DATA_KEY ||
1339 found_key.offset > end)
1340 break;
1341
1342 if (found_key.offset > cur_offset) {
1343 extent_end = found_key.offset;
1344 extent_type = 0;
1345 goto out_check;
1346 }
1347
1348 fi = btrfs_item_ptr(leaf, path->slots[0],
1349 struct btrfs_file_extent_item);
1350 extent_type = btrfs_file_extent_type(leaf, fi);
1351
1352 ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
1353 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1354 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1355 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1356 extent_offset = btrfs_file_extent_offset(leaf, fi);
1357 extent_end = found_key.offset +
1358 btrfs_file_extent_num_bytes(leaf, fi);
1359 disk_num_bytes =
1360 btrfs_file_extent_disk_num_bytes(leaf, fi);
1361 if (extent_end <= start) {
1362 path->slots[0]++;
1363 goto next_slot;
1364 }
1365 if (disk_bytenr == 0)
1366 goto out_check;
1367 if (btrfs_file_extent_compression(leaf, fi) ||
1368 btrfs_file_extent_encryption(leaf, fi) ||
1369 btrfs_file_extent_other_encoding(leaf, fi))
1370 goto out_check;
1371 /*
1372 * Do the same check as in btrfs_cross_ref_exist but
1373 * without the unnecessary search.
1374 */
1375 if (btrfs_file_extent_generation(leaf, fi) <=
1376 btrfs_root_last_snapshot(&root->root_item))
1377 goto out_check;
1378 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1379 goto out_check;
1380 if (btrfs_extent_readonly(fs_info, disk_bytenr))
1381 goto out_check;
1382 ret = btrfs_cross_ref_exist(root, ino,
1383 found_key.offset -
1384 extent_offset, disk_bytenr);
1385 if (ret) {
1386 /*
1387 * ret could be -EIO if the above fails to read
1388 * metadata.
1389 */
1390 if (ret < 0) {
1391 if (cow_start != (u64)-1)
1392 cur_offset = cow_start;
1393 goto error;
1394 }
1395
1396 WARN_ON_ONCE(nolock);
1397 goto out_check;
1398 }
1399 disk_bytenr += extent_offset;
1400 disk_bytenr += cur_offset - found_key.offset;
1401 num_bytes = min(end + 1, extent_end) - cur_offset;
1402 /*
1403 * if there are pending snapshots for this root,
1404 * we fall into common COW way.
1405 */
1406 if (!nolock && atomic_read(&root->snapshot_force_cow))
1407 goto out_check;
1408 /*
1409 * force cow if csum exists in the range.
1410 * this ensure that csum for a given extent are
1411 * either valid or do not exist.
1412 */
1413 ret = csum_exist_in_range(fs_info, disk_bytenr,
1414 num_bytes);
1415 if (ret) {
1416 /*
1417 * ret could be -EIO if the above fails to read
1418 * metadata.
1419 */
1420 if (ret < 0) {
1421 if (cow_start != (u64)-1)
1422 cur_offset = cow_start;
1423 goto error;
1424 }
1425 WARN_ON_ONCE(nolock);
1426 goto out_check;
1427 }
1428 if (!btrfs_inc_nocow_writers(fs_info, disk_bytenr))
1429 goto out_check;
1430 nocow = 1;
1431 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1432 extent_end = found_key.offset +
1433 btrfs_file_extent_ram_bytes(leaf, fi);
1434 extent_end = ALIGN(extent_end,
1435 fs_info->sectorsize);
1436 } else {
1437 BUG_ON(1);
1438 }
1439 out_check:
1440 if (extent_end <= start) {
1441 path->slots[0]++;
1442 if (nocow)
1443 btrfs_dec_nocow_writers(fs_info, disk_bytenr);
1444 goto next_slot;
1445 }
1446 if (!nocow) {
1447 if (cow_start == (u64)-1)
1448 cow_start = cur_offset;
1449 cur_offset = extent_end;
1450 if (cur_offset > end)
1451 break;
1452 path->slots[0]++;
1453 goto next_slot;
1454 }
1455
1456 btrfs_release_path(path);
1457 if (cow_start != (u64)-1) {
1458 ret = cow_file_range(inode, locked_page,
1459 cow_start, found_key.offset - 1,
1460 end, page_started, nr_written, 1,
1461 NULL);
1462 if (ret) {
1463 if (nocow)
1464 btrfs_dec_nocow_writers(fs_info,
1465 disk_bytenr);
1466 goto error;
1467 }
1468 cow_start = (u64)-1;
1469 }
1470
1471 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1472 u64 orig_start = found_key.offset - extent_offset;
1473
1474 em = create_io_em(inode, cur_offset, num_bytes,
1475 orig_start,
1476 disk_bytenr, /* block_start */
1477 num_bytes, /* block_len */
1478 disk_num_bytes, /* orig_block_len */
1479 ram_bytes, BTRFS_COMPRESS_NONE,
1480 BTRFS_ORDERED_PREALLOC);
1481 if (IS_ERR(em)) {
1482 if (nocow)
1483 btrfs_dec_nocow_writers(fs_info,
1484 disk_bytenr);
1485 ret = PTR_ERR(em);
1486 goto error;
1487 }
1488 free_extent_map(em);
1489 }
1490
1491 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1492 type = BTRFS_ORDERED_PREALLOC;
1493 } else {
1494 type = BTRFS_ORDERED_NOCOW;
1495 }
1496
1497 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr,
1498 num_bytes, num_bytes, type);
1499 if (nocow)
1500 btrfs_dec_nocow_writers(fs_info, disk_bytenr);
1501 BUG_ON(ret); /* -ENOMEM */
1502
1503 if (root->root_key.objectid ==
1504 BTRFS_DATA_RELOC_TREE_OBJECTID)
1505 /*
1506 * Error handled later, as we must prevent
1507 * extent_clear_unlock_delalloc() in error handler
1508 * from freeing metadata of created ordered extent.
1509 */
1510 ret = btrfs_reloc_clone_csums(inode, cur_offset,
1511 num_bytes);
1512
1513 extent_clear_unlock_delalloc(inode, cur_offset,
1514 cur_offset + num_bytes - 1, end,
1515 locked_page, EXTENT_LOCKED |
1516 EXTENT_DELALLOC |
1517 EXTENT_CLEAR_DATA_RESV,
1518 PAGE_UNLOCK | PAGE_SET_PRIVATE2);
1519
1520 cur_offset = extent_end;
1521
1522 /*
1523 * btrfs_reloc_clone_csums() error, now we're OK to call error
1524 * handler, as metadata for created ordered extent will only
1525 * be freed by btrfs_finish_ordered_io().
1526 */
1527 if (ret)
1528 goto error;
1529 if (cur_offset > end)
1530 break;
1531 }
1532 btrfs_release_path(path);
1533
1534 if (cur_offset <= end && cow_start == (u64)-1) {
1535 cow_start = cur_offset;
1536 cur_offset = end;
1537 }
1538
1539 if (cow_start != (u64)-1) {
1540 ret = cow_file_range(inode, locked_page, cow_start, end, end,
1541 page_started, nr_written, 1, NULL);
1542 if (ret)
1543 goto error;
1544 }
1545
1546 error:
1547 if (ret && cur_offset < end)
1548 extent_clear_unlock_delalloc(inode, cur_offset, end, end,
1549 locked_page, EXTENT_LOCKED |
1550 EXTENT_DELALLOC | EXTENT_DEFRAG |
1551 EXTENT_DO_ACCOUNTING, PAGE_UNLOCK |
1552 PAGE_CLEAR_DIRTY |
1553 PAGE_SET_WRITEBACK |
1554 PAGE_END_WRITEBACK);
1555 btrfs_free_path(path);
1556 return ret;
1557 }
1558
1559 static inline int need_force_cow(struct inode *inode, u64 start, u64 end)
1560 {
1561
1562 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
1563 !(BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC))
1564 return 0;
1565
1566 /*
1567 * @defrag_bytes is a hint value, no spinlock held here,
1568 * if is not zero, it means the file is defragging.
1569 * Force cow if given extent needs to be defragged.
1570 */
1571 if (BTRFS_I(inode)->defrag_bytes &&
1572 test_range_bit(&BTRFS_I(inode)->io_tree, start, end,
1573 EXTENT_DEFRAG, 0, NULL))
1574 return 1;
1575
1576 return 0;
1577 }
1578
1579 /*
1580 * extent_io.c call back to do delayed allocation processing
1581 */
1582 static int run_delalloc_range(void *private_data, struct page *locked_page,
1583 u64 start, u64 end, int *page_started,
1584 unsigned long *nr_written,
1585 struct writeback_control *wbc)
1586 {
1587 struct inode *inode = private_data;
1588 int ret;
1589 int force_cow = need_force_cow(inode, start, end);
1590 unsigned int write_flags = wbc_to_write_flags(wbc);
1591
1592 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW && !force_cow) {
1593 ret = run_delalloc_nocow(inode, locked_page, start, end,
1594 page_started, 1, nr_written);
1595 } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC && !force_cow) {
1596 ret = run_delalloc_nocow(inode, locked_page, start, end,
1597 page_started, 0, nr_written);
1598 } else if (!inode_need_compress(inode, start, end)) {
1599 ret = cow_file_range(inode, locked_page, start, end, end,
1600 page_started, nr_written, 1, NULL);
1601 } else {
1602 set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1603 &BTRFS_I(inode)->runtime_flags);
1604 ret = cow_file_range_async(inode, locked_page, start, end,
1605 page_started, nr_written,
1606 write_flags);
1607 }
1608 if (ret)
1609 btrfs_cleanup_ordered_extents(inode, start, end - start + 1);
1610 return ret;
1611 }
1612
1613 static void btrfs_split_extent_hook(void *private_data,
1614 struct extent_state *orig, u64 split)
1615 {
1616 struct inode *inode = private_data;
1617 u64 size;
1618
1619 /* not delalloc, ignore it */
1620 if (!(orig->state & EXTENT_DELALLOC))
1621 return;
1622
1623 size = orig->end - orig->start + 1;
1624 if (size > BTRFS_MAX_EXTENT_SIZE) {
1625 u32 num_extents;
1626 u64 new_size;
1627
1628 /*
1629 * See the explanation in btrfs_merge_extent_hook, the same
1630 * applies here, just in reverse.
1631 */
1632 new_size = orig->end - split + 1;
1633 num_extents = count_max_extents(new_size);
1634 new_size = split - orig->start;
1635 num_extents += count_max_extents(new_size);
1636 if (count_max_extents(size) >= num_extents)
1637 return;
1638 }
1639
1640 spin_lock(&BTRFS_I(inode)->lock);
1641 btrfs_mod_outstanding_extents(BTRFS_I(inode), 1);
1642 spin_unlock(&BTRFS_I(inode)->lock);
1643 }
1644
1645 /*
1646 * extent_io.c merge_extent_hook, used to track merged delayed allocation
1647 * extents so we can keep track of new extents that are just merged onto old
1648 * extents, such as when we are doing sequential writes, so we can properly
1649 * account for the metadata space we'll need.
1650 */
1651 static void btrfs_merge_extent_hook(void *private_data,
1652 struct extent_state *new,
1653 struct extent_state *other)
1654 {
1655 struct inode *inode = private_data;
1656 u64 new_size, old_size;
1657 u32 num_extents;
1658
1659 /* not delalloc, ignore it */
1660 if (!(other->state & EXTENT_DELALLOC))
1661 return;
1662
1663 if (new->start > other->start)
1664 new_size = new->end - other->start + 1;
1665 else
1666 new_size = other->end - new->start + 1;
1667
1668 /* we're not bigger than the max, unreserve the space and go */
1669 if (new_size <= BTRFS_MAX_EXTENT_SIZE) {
1670 spin_lock(&BTRFS_I(inode)->lock);
1671 btrfs_mod_outstanding_extents(BTRFS_I(inode), -1);
1672 spin_unlock(&BTRFS_I(inode)->lock);
1673 return;
1674 }
1675
1676 /*
1677 * We have to add up either side to figure out how many extents were
1678 * accounted for before we merged into one big extent. If the number of
1679 * extents we accounted for is <= the amount we need for the new range
1680 * then we can return, otherwise drop. Think of it like this
1681 *
1682 * [ 4k][MAX_SIZE]
1683 *
1684 * So we've grown the extent by a MAX_SIZE extent, this would mean we
1685 * need 2 outstanding extents, on one side we have 1 and the other side
1686 * we have 1 so they are == and we can return. But in this case
1687 *
1688 * [MAX_SIZE+4k][MAX_SIZE+4k]
1689 *
1690 * Each range on their own accounts for 2 extents, but merged together
1691 * they are only 3 extents worth of accounting, so we need to drop in
1692 * this case.
1693 */
1694 old_size = other->end - other->start + 1;
1695 num_extents = count_max_extents(old_size);
1696 old_size = new->end - new->start + 1;
1697 num_extents += count_max_extents(old_size);
1698 if (count_max_extents(new_size) >= num_extents)
1699 return;
1700
1701 spin_lock(&BTRFS_I(inode)->lock);
1702 btrfs_mod_outstanding_extents(BTRFS_I(inode), -1);
1703 spin_unlock(&BTRFS_I(inode)->lock);
1704 }
1705
1706 static void btrfs_add_delalloc_inodes(struct btrfs_root *root,
1707 struct inode *inode)
1708 {
1709 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1710
1711 spin_lock(&root->delalloc_lock);
1712 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1713 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1714 &root->delalloc_inodes);
1715 set_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1716 &BTRFS_I(inode)->runtime_flags);
1717 root->nr_delalloc_inodes++;
1718 if (root->nr_delalloc_inodes == 1) {
1719 spin_lock(&fs_info->delalloc_root_lock);
1720 BUG_ON(!list_empty(&root->delalloc_root));
1721 list_add_tail(&root->delalloc_root,
1722 &fs_info->delalloc_roots);
1723 spin_unlock(&fs_info->delalloc_root_lock);
1724 }
1725 }
1726 spin_unlock(&root->delalloc_lock);
1727 }
1728
1729
1730 void __btrfs_del_delalloc_inode(struct btrfs_root *root,
1731 struct btrfs_inode *inode)
1732 {
1733 struct btrfs_fs_info *fs_info = root->fs_info;
1734
1735 if (!list_empty(&inode->delalloc_inodes)) {
1736 list_del_init(&inode->delalloc_inodes);
1737 clear_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1738 &inode->runtime_flags);
1739 root->nr_delalloc_inodes--;
1740 if (!root->nr_delalloc_inodes) {
1741 ASSERT(list_empty(&root->delalloc_inodes));
1742 spin_lock(&fs_info->delalloc_root_lock);
1743 BUG_ON(list_empty(&root->delalloc_root));
1744 list_del_init(&root->delalloc_root);
1745 spin_unlock(&fs_info->delalloc_root_lock);
1746 }
1747 }
1748 }
1749
1750 static void btrfs_del_delalloc_inode(struct btrfs_root *root,
1751 struct btrfs_inode *inode)
1752 {
1753 spin_lock(&root->delalloc_lock);
1754 __btrfs_del_delalloc_inode(root, inode);
1755 spin_unlock(&root->delalloc_lock);
1756 }
1757
1758 /*
1759 * extent_io.c set_bit_hook, used to track delayed allocation
1760 * bytes in this file, and to maintain the list of inodes that
1761 * have pending delalloc work to be done.
1762 */
1763 static void btrfs_set_bit_hook(void *private_data,
1764 struct extent_state *state, unsigned *bits)
1765 {
1766 struct inode *inode = private_data;
1767
1768 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1769
1770 if ((*bits & EXTENT_DEFRAG) && !(*bits & EXTENT_DELALLOC))
1771 WARN_ON(1);
1772 /*
1773 * set_bit and clear bit hooks normally require _irqsave/restore
1774 * but in this case, we are only testing for the DELALLOC
1775 * bit, which is only set or cleared with irqs on
1776 */
1777 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1778 struct btrfs_root *root = BTRFS_I(inode)->root;
1779 u64 len = state->end + 1 - state->start;
1780 u32 num_extents = count_max_extents(len);
1781 bool do_list = !btrfs_is_free_space_inode(BTRFS_I(inode));
1782
1783 spin_lock(&BTRFS_I(inode)->lock);
1784 btrfs_mod_outstanding_extents(BTRFS_I(inode), num_extents);
1785 spin_unlock(&BTRFS_I(inode)->lock);
1786
1787 /* For sanity tests */
1788 if (btrfs_is_testing(fs_info))
1789 return;
1790
1791 percpu_counter_add_batch(&fs_info->delalloc_bytes, len,
1792 fs_info->delalloc_batch);
1793 spin_lock(&BTRFS_I(inode)->lock);
1794 BTRFS_I(inode)->delalloc_bytes += len;
1795 if (*bits & EXTENT_DEFRAG)
1796 BTRFS_I(inode)->defrag_bytes += len;
1797 if (do_list && !test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1798 &BTRFS_I(inode)->runtime_flags))
1799 btrfs_add_delalloc_inodes(root, inode);
1800 spin_unlock(&BTRFS_I(inode)->lock);
1801 }
1802
1803 if (!(state->state & EXTENT_DELALLOC_NEW) &&
1804 (*bits & EXTENT_DELALLOC_NEW)) {
1805 spin_lock(&BTRFS_I(inode)->lock);
1806 BTRFS_I(inode)->new_delalloc_bytes += state->end + 1 -
1807 state->start;
1808 spin_unlock(&BTRFS_I(inode)->lock);
1809 }
1810 }
1811
1812 /*
1813 * extent_io.c clear_bit_hook, see set_bit_hook for why
1814 */
1815 static void btrfs_clear_bit_hook(void *private_data,
1816 struct extent_state *state,
1817 unsigned *bits)
1818 {
1819 struct btrfs_inode *inode = BTRFS_I((struct inode *)private_data);
1820 struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb);
1821 u64 len = state->end + 1 - state->start;
1822 u32 num_extents = count_max_extents(len);
1823
1824 if ((state->state & EXTENT_DEFRAG) && (*bits & EXTENT_DEFRAG)) {
1825 spin_lock(&inode->lock);
1826 inode->defrag_bytes -= len;
1827 spin_unlock(&inode->lock);
1828 }
1829
1830 /*
1831 * set_bit and clear bit hooks normally require _irqsave/restore
1832 * but in this case, we are only testing for the DELALLOC
1833 * bit, which is only set or cleared with irqs on
1834 */
1835 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1836 struct btrfs_root *root = inode->root;
1837 bool do_list = !btrfs_is_free_space_inode(inode);
1838
1839 spin_lock(&inode->lock);
1840 btrfs_mod_outstanding_extents(inode, -num_extents);
1841 spin_unlock(&inode->lock);
1842
1843 /*
1844 * We don't reserve metadata space for space cache inodes so we
1845 * don't need to call dellalloc_release_metadata if there is an
1846 * error.
1847 */
1848 if (*bits & EXTENT_CLEAR_META_RESV &&
1849 root != fs_info->tree_root)
1850 btrfs_delalloc_release_metadata(inode, len, false);
1851
1852 /* For sanity tests. */
1853 if (btrfs_is_testing(fs_info))
1854 return;
1855
1856 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID &&
1857 do_list && !(state->state & EXTENT_NORESERVE) &&
1858 (*bits & EXTENT_CLEAR_DATA_RESV))
1859 btrfs_free_reserved_data_space_noquota(
1860 &inode->vfs_inode,
1861 state->start, len);
1862
1863 percpu_counter_add_batch(&fs_info->delalloc_bytes, -len,
1864 fs_info->delalloc_batch);
1865 spin_lock(&inode->lock);
1866 inode->delalloc_bytes -= len;
1867 if (do_list && inode->delalloc_bytes == 0 &&
1868 test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1869 &inode->runtime_flags))
1870 btrfs_del_delalloc_inode(root, inode);
1871 spin_unlock(&inode->lock);
1872 }
1873
1874 if ((state->state & EXTENT_DELALLOC_NEW) &&
1875 (*bits & EXTENT_DELALLOC_NEW)) {
1876 spin_lock(&inode->lock);
1877 ASSERT(inode->new_delalloc_bytes >= len);
1878 inode->new_delalloc_bytes -= len;
1879 spin_unlock(&inode->lock);
1880 }
1881 }
1882
1883 /*
1884 * Merge bio hook, this must check the chunk tree to make sure we don't create
1885 * bios that span stripes or chunks
1886 *
1887 * return 1 if page cannot be merged to bio
1888 * return 0 if page can be merged to bio
1889 * return error otherwise
1890 */
1891 int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
1892 size_t size, struct bio *bio,
1893 unsigned long bio_flags)
1894 {
1895 struct inode *inode = page->mapping->host;
1896 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1897 u64 logical = (u64)bio->bi_iter.bi_sector << 9;
1898 u64 length = 0;
1899 u64 map_length;
1900 int ret;
1901
1902 if (bio_flags & EXTENT_BIO_COMPRESSED)
1903 return 0;
1904
1905 length = bio->bi_iter.bi_size;
1906 map_length = length;
1907 ret = btrfs_map_block(fs_info, btrfs_op(bio), logical, &map_length,
1908 NULL, 0);
1909 if (ret < 0)
1910 return ret;
1911 if (map_length < length + size)
1912 return 1;
1913 return 0;
1914 }
1915
1916 /*
1917 * in order to insert checksums into the metadata in large chunks,
1918 * we wait until bio submission time. All the pages in the bio are
1919 * checksummed and sums are attached onto the ordered extent record.
1920 *
1921 * At IO completion time the cums attached on the ordered extent record
1922 * are inserted into the btree
1923 */
1924 static blk_status_t btrfs_submit_bio_start(void *private_data, struct bio *bio,
1925 u64 bio_offset)
1926 {
1927 struct inode *inode = private_data;
1928 blk_status_t ret = 0;
1929
1930 ret = btrfs_csum_one_bio(inode, bio, 0, 0);
1931 BUG_ON(ret); /* -ENOMEM */
1932 return 0;
1933 }
1934
1935 /*
1936 * in order to insert checksums into the metadata in large chunks,
1937 * we wait until bio submission time. All the pages in the bio are
1938 * checksummed and sums are attached onto the ordered extent record.
1939 *
1940 * At IO completion time the cums attached on the ordered extent record
1941 * are inserted into the btree
1942 */
1943 blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
1944 int mirror_num)
1945 {
1946 struct inode *inode = private_data;
1947 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1948 blk_status_t ret;
1949
1950 ret = btrfs_map_bio(fs_info, bio, mirror_num, 1);
1951 if (ret) {
1952 bio->bi_status = ret;
1953 bio_endio(bio);
1954 }
1955 return ret;
1956 }
1957
1958 /*
1959 * extent_io.c submission hook. This does the right thing for csum calculation
1960 * on write, or reading the csums from the tree before a read.
1961 *
1962 * Rules about async/sync submit,
1963 * a) read: sync submit
1964 *
1965 * b) write without checksum: sync submit
1966 *
1967 * c) write with checksum:
1968 * c-1) if bio is issued by fsync: sync submit
1969 * (sync_writers != 0)
1970 *
1971 * c-2) if root is reloc root: sync submit
1972 * (only in case of buffered IO)
1973 *
1974 * c-3) otherwise: async submit
1975 */
1976 static blk_status_t btrfs_submit_bio_hook(void *private_data, struct bio *bio,
1977 int mirror_num, unsigned long bio_flags,
1978 u64 bio_offset)
1979 {
1980 struct inode *inode = private_data;
1981 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1982 struct btrfs_root *root = BTRFS_I(inode)->root;
1983 enum btrfs_wq_endio_type metadata = BTRFS_WQ_ENDIO_DATA;
1984 blk_status_t ret = 0;
1985 int skip_sum;
1986 int async = !atomic_read(&BTRFS_I(inode)->sync_writers);
1987
1988 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
1989
1990 if (btrfs_is_free_space_inode(BTRFS_I(inode)))
1991 metadata = BTRFS_WQ_ENDIO_FREE_SPACE;
1992
1993 if (bio_op(bio) != REQ_OP_WRITE) {
1994 ret = btrfs_bio_wq_end_io(fs_info, bio, metadata);
1995 if (ret)
1996 goto out;
1997
1998 if (bio_flags & EXTENT_BIO_COMPRESSED) {
1999 ret = btrfs_submit_compressed_read(inode, bio,
2000 mirror_num,
2001 bio_flags);
2002 goto out;
2003 } else if (!skip_sum) {
2004 ret = btrfs_lookup_bio_sums(inode, bio, NULL);
2005 if (ret)
2006 goto out;
2007 }
2008 goto mapit;
2009 } else if (async && !skip_sum) {
2010 /* csum items have already been cloned */
2011 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2012 goto mapit;
2013 /* we're doing a write, do the async checksumming */
2014 ret = btrfs_wq_submit_bio(fs_info, bio, mirror_num, bio_flags,
2015 bio_offset, inode,
2016 btrfs_submit_bio_start);
2017 goto out;
2018 } else if (!skip_sum) {
2019 ret = btrfs_csum_one_bio(inode, bio, 0, 0);
2020 if (ret)
2021 goto out;
2022 }
2023
2024 mapit:
2025 ret = btrfs_map_bio(fs_info, bio, mirror_num, 0);
2026
2027 out:
2028 if (ret) {
2029 bio->bi_status = ret;
2030 bio_endio(bio);
2031 }
2032 return ret;
2033 }
2034
2035 /*
2036 * given a list of ordered sums record them in the inode. This happens
2037 * at IO completion time based on sums calculated at bio submission time.
2038 */
2039 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
2040 struct inode *inode, struct list_head *list)
2041 {
2042 struct btrfs_ordered_sum *sum;
2043 int ret;
2044
2045 list_for_each_entry(sum, list, list) {
2046 trans->adding_csums = true;
2047 ret = btrfs_csum_file_blocks(trans,
2048 BTRFS_I(inode)->root->fs_info->csum_root, sum);
2049 trans->adding_csums = false;
2050 if (ret)
2051 return ret;
2052 }
2053 return 0;
2054 }
2055
2056 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
2057 unsigned int extra_bits,
2058 struct extent_state **cached_state, int dedupe)
2059 {
2060 WARN_ON((end & (PAGE_SIZE - 1)) == 0);
2061 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
2062 extra_bits, cached_state);
2063 }
2064
2065 /* see btrfs_writepage_start_hook for details on why this is required */
2066 struct btrfs_writepage_fixup {
2067 struct page *page;
2068 struct btrfs_work work;
2069 };
2070
2071 static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
2072 {
2073 struct btrfs_writepage_fixup *fixup;
2074 struct btrfs_ordered_extent *ordered;
2075 struct extent_state *cached_state = NULL;
2076 struct extent_changeset *data_reserved = NULL;
2077 struct page *page;
2078 struct inode *inode;
2079 u64 page_start;
2080 u64 page_end;
2081 int ret;
2082
2083 fixup = container_of(work, struct btrfs_writepage_fixup, work);
2084 page = fixup->page;
2085 again:
2086 lock_page(page);
2087 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
2088 ClearPageChecked(page);
2089 goto out_page;
2090 }
2091
2092 inode = page->mapping->host;
2093 page_start = page_offset(page);
2094 page_end = page_offset(page) + PAGE_SIZE - 1;
2095
2096 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end,
2097 &cached_state);
2098
2099 /* already ordered? We're done */
2100 if (PagePrivate2(page))
2101 goto out;
2102
2103 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), page_start,
2104 PAGE_SIZE);
2105 if (ordered) {
2106 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start,
2107 page_end, &cached_state);
2108 unlock_page(page);
2109 btrfs_start_ordered_extent(inode, ordered, 1);
2110 btrfs_put_ordered_extent(ordered);
2111 goto again;
2112 }
2113
2114 ret = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start,
2115 PAGE_SIZE);
2116 if (ret) {
2117 mapping_set_error(page->mapping, ret);
2118 end_extent_writepage(page, ret, page_start, page_end);
2119 ClearPageChecked(page);
2120 goto out;
2121 }
2122
2123 ret = btrfs_set_extent_delalloc(inode, page_start, page_end, 0,
2124 &cached_state, 0);
2125 if (ret) {
2126 mapping_set_error(page->mapping, ret);
2127 end_extent_writepage(page, ret, page_start, page_end);
2128 ClearPageChecked(page);
2129 goto out;
2130 }
2131
2132 ClearPageChecked(page);
2133 set_page_dirty(page);
2134 btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, false);
2135 out:
2136 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
2137 &cached_state);
2138 out_page:
2139 unlock_page(page);
2140 put_page(page);
2141 kfree(fixup);
2142 extent_changeset_free(data_reserved);
2143 }
2144
2145 /*
2146 * There are a few paths in the higher layers of the kernel that directly
2147 * set the page dirty bit without asking the filesystem if it is a
2148 * good idea. This causes problems because we want to make sure COW
2149 * properly happens and the data=ordered rules are followed.
2150 *
2151 * In our case any range that doesn't have the ORDERED bit set
2152 * hasn't been properly setup for IO. We kick off an async process
2153 * to fix it up. The async helper will wait for ordered extents, set
2154 * the delalloc bit and make it safe to write the page.
2155 */
2156 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
2157 {
2158 struct inode *inode = page->mapping->host;
2159 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2160 struct btrfs_writepage_fixup *fixup;
2161
2162 /* this page is properly in the ordered list */
2163 if (TestClearPagePrivate2(page))
2164 return 0;
2165
2166 if (PageChecked(page))
2167 return -EAGAIN;
2168
2169 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
2170 if (!fixup)
2171 return -EAGAIN;
2172
2173 SetPageChecked(page);
2174 get_page(page);
2175 btrfs_init_work(&fixup->work, btrfs_fixup_helper,
2176 btrfs_writepage_fixup_worker, NULL, NULL);
2177 fixup->page = page;
2178 btrfs_queue_work(fs_info->fixup_workers, &fixup->work);
2179 return -EBUSY;
2180 }
2181
2182 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
2183 struct inode *inode, u64 file_pos,
2184 u64 disk_bytenr, u64 disk_num_bytes,
2185 u64 num_bytes, u64 ram_bytes,
2186 u8 compression, u8 encryption,
2187 u16 other_encoding, int extent_type)
2188 {
2189 struct btrfs_root *root = BTRFS_I(inode)->root;
2190 struct btrfs_file_extent_item *fi;
2191 struct btrfs_path *path;
2192 struct extent_buffer *leaf;
2193 struct btrfs_key ins;
2194 u64 qg_released;
2195 int extent_inserted = 0;
2196 int ret;
2197
2198 path = btrfs_alloc_path();
2199 if (!path)
2200 return -ENOMEM;
2201
2202 /*
2203 * we may be replacing one extent in the tree with another.
2204 * The new extent is pinned in the extent map, and we don't want
2205 * to drop it from the cache until it is completely in the btree.
2206 *
2207 * So, tell btrfs_drop_extents to leave this extent in the cache.
2208 * the caller is expected to unpin it and allow it to be merged
2209 * with the others.
2210 */
2211 ret = __btrfs_drop_extents(trans, root, inode, path, file_pos,
2212 file_pos + num_bytes, NULL, 0,
2213 1, sizeof(*fi), &extent_inserted);
2214 if (ret)
2215 goto out;
2216
2217 if (!extent_inserted) {
2218 ins.objectid = btrfs_ino(BTRFS_I(inode));
2219 ins.offset = file_pos;
2220 ins.type = BTRFS_EXTENT_DATA_KEY;
2221
2222 path->leave_spinning = 1;
2223 ret = btrfs_insert_empty_item(trans, root, path, &ins,
2224 sizeof(*fi));
2225 if (ret)
2226 goto out;
2227 }
2228 leaf = path->nodes[0];
2229 fi = btrfs_item_ptr(leaf, path->slots[0],
2230 struct btrfs_file_extent_item);
2231 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
2232 btrfs_set_file_extent_type(leaf, fi, extent_type);
2233 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
2234 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
2235 btrfs_set_file_extent_offset(leaf, fi, 0);
2236 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
2237 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
2238 btrfs_set_file_extent_compression(leaf, fi, compression);
2239 btrfs_set_file_extent_encryption(leaf, fi, encryption);
2240 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
2241
2242 btrfs_mark_buffer_dirty(leaf);
2243 btrfs_release_path(path);
2244
2245 inode_add_bytes(inode, num_bytes);
2246
2247 ins.objectid = disk_bytenr;
2248 ins.offset = disk_num_bytes;
2249 ins.type = BTRFS_EXTENT_ITEM_KEY;
2250
2251 /*
2252 * Release the reserved range from inode dirty range map, as it is
2253 * already moved into delayed_ref_head
2254 */
2255 ret = btrfs_qgroup_release_data(inode, file_pos, ram_bytes);
2256 if (ret < 0)
2257 goto out;
2258 qg_released = ret;
2259 ret = btrfs_alloc_reserved_file_extent(trans, root,
2260 btrfs_ino(BTRFS_I(inode)),
2261 file_pos, qg_released, &ins);
2262 out:
2263 btrfs_free_path(path);
2264
2265 return ret;
2266 }
2267
2268 /* snapshot-aware defrag */
2269 struct sa_defrag_extent_backref {
2270 struct rb_node node;
2271 struct old_sa_defrag_extent *old;
2272 u64 root_id;
2273 u64 inum;
2274 u64 file_pos;
2275 u64 extent_offset;
2276 u64 num_bytes;
2277 u64 generation;
2278 };
2279
2280 struct old_sa_defrag_extent {
2281 struct list_head list;
2282 struct new_sa_defrag_extent *new;
2283
2284 u64 extent_offset;
2285 u64 bytenr;
2286 u64 offset;
2287 u64 len;
2288 int count;
2289 };
2290
2291 struct new_sa_defrag_extent {
2292 struct rb_root root;
2293 struct list_head head;
2294 struct btrfs_path *path;
2295 struct inode *inode;
2296 u64 file_pos;
2297 u64 len;
2298 u64 bytenr;
2299 u64 disk_len;
2300 u8 compress_type;
2301 };
2302
2303 static int backref_comp(struct sa_defrag_extent_backref *b1,
2304 struct sa_defrag_extent_backref *b2)
2305 {
2306 if (b1->root_id < b2->root_id)
2307 return -1;
2308 else if (b1->root_id > b2->root_id)
2309 return 1;
2310
2311 if (b1->inum < b2->inum)
2312 return -1;
2313 else if (b1->inum > b2->inum)
2314 return 1;
2315
2316 if (b1->file_pos < b2->file_pos)
2317 return -1;
2318 else if (b1->file_pos > b2->file_pos)
2319 return 1;
2320
2321 /*
2322 * [------------------------------] ===> (a range of space)
2323 * |<--->| |<---->| =============> (fs/file tree A)
2324 * |<---------------------------->| ===> (fs/file tree B)
2325 *
2326 * A range of space can refer to two file extents in one tree while
2327 * refer to only one file extent in another tree.
2328 *
2329 * So we may process a disk offset more than one time(two extents in A)
2330 * and locate at the same extent(one extent in B), then insert two same
2331 * backrefs(both refer to the extent in B).
2332 */
2333 return 0;
2334 }
2335
2336 static void backref_insert(struct rb_root *root,
2337 struct sa_defrag_extent_backref *backref)
2338 {
2339 struct rb_node **p = &root->rb_node;
2340 struct rb_node *parent = NULL;
2341 struct sa_defrag_extent_backref *entry;
2342 int ret;
2343
2344 while (*p) {
2345 parent = *p;
2346 entry = rb_entry(parent, struct sa_defrag_extent_backref, node);
2347
2348 ret = backref_comp(backref, entry);
2349 if (ret < 0)
2350 p = &(*p)->rb_left;
2351 else
2352 p = &(*p)->rb_right;
2353 }
2354
2355 rb_link_node(&backref->node, parent, p);
2356 rb_insert_color(&backref->node, root);
2357 }
2358
2359 /*
2360 * Note the backref might has changed, and in this case we just return 0.
2361 */
2362 static noinline int record_one_backref(u64 inum, u64 offset, u64 root_id,
2363 void *ctx)
2364 {
2365 struct btrfs_file_extent_item *extent;
2366 struct old_sa_defrag_extent *old = ctx;
2367 struct new_sa_defrag_extent *new = old->new;
2368 struct btrfs_path *path = new->path;
2369 struct btrfs_key key;
2370 struct btrfs_root *root;
2371 struct sa_defrag_extent_backref *backref;
2372 struct extent_buffer *leaf;
2373 struct inode *inode = new->inode;
2374 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2375 int slot;
2376 int ret;
2377 u64 extent_offset;
2378 u64 num_bytes;
2379
2380 if (BTRFS_I(inode)->root->root_key.objectid == root_id &&
2381 inum == btrfs_ino(BTRFS_I(inode)))
2382 return 0;
2383
2384 key.objectid = root_id;
2385 key.type = BTRFS_ROOT_ITEM_KEY;
2386 key.offset = (u64)-1;
2387
2388 root = btrfs_read_fs_root_no_name(fs_info, &key);
2389 if (IS_ERR(root)) {
2390 if (PTR_ERR(root) == -ENOENT)
2391 return 0;
2392 WARN_ON(1);
2393 btrfs_debug(fs_info, "inum=%llu, offset=%llu, root_id=%llu",
2394 inum, offset, root_id);
2395 return PTR_ERR(root);
2396 }
2397
2398 key.objectid = inum;
2399 key.type = BTRFS_EXTENT_DATA_KEY;
2400 if (offset > (u64)-1 << 32)
2401 key.offset = 0;
2402 else
2403 key.offset = offset;
2404
2405 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2406 if (WARN_ON(ret < 0))
2407 return ret;
2408 ret = 0;
2409
2410 while (1) {
2411 cond_resched();
2412
2413 leaf = path->nodes[0];
2414 slot = path->slots[0];
2415
2416 if (slot >= btrfs_header_nritems(leaf)) {
2417 ret = btrfs_next_leaf(root, path);
2418 if (ret < 0) {
2419 goto out;
2420 } else if (ret > 0) {
2421 ret = 0;
2422 goto out;
2423 }
2424 continue;
2425 }
2426
2427 path->slots[0]++;
2428
2429 btrfs_item_key_to_cpu(leaf, &key, slot);
2430
2431 if (key.objectid > inum)
2432 goto out;
2433
2434 if (key.objectid < inum || key.type != BTRFS_EXTENT_DATA_KEY)
2435 continue;
2436
2437 extent = btrfs_item_ptr(leaf, slot,
2438 struct btrfs_file_extent_item);
2439
2440 if (btrfs_file_extent_disk_bytenr(leaf, extent) != old->bytenr)
2441 continue;
2442
2443 /*
2444 * 'offset' refers to the exact key.offset,
2445 * NOT the 'offset' field in btrfs_extent_data_ref, ie.
2446 * (key.offset - extent_offset).
2447 */
2448 if (key.offset != offset)
2449 continue;
2450
2451 extent_offset = btrfs_file_extent_offset(leaf, extent);
2452 num_bytes = btrfs_file_extent_num_bytes(leaf, extent);
2453
2454 if (extent_offset >= old->extent_offset + old->offset +
2455 old->len || extent_offset + num_bytes <=
2456 old->extent_offset + old->offset)
2457 continue;
2458 break;
2459 }
2460
2461 backref = kmalloc(sizeof(*backref), GFP_NOFS);
2462 if (!backref) {
2463 ret = -ENOENT;
2464 goto out;
2465 }
2466
2467 backref->root_id = root_id;
2468 backref->inum = inum;
2469 backref->file_pos = offset;
2470 backref->num_bytes = num_bytes;
2471 backref->extent_offset = extent_offset;
2472 backref->generation = btrfs_file_extent_generation(leaf, extent);
2473 backref->old = old;
2474 backref_insert(&new->root, backref);
2475 old->count++;
2476 out:
2477 btrfs_release_path(path);
2478 WARN_ON(ret);
2479 return ret;
2480 }
2481
2482 static noinline bool record_extent_backrefs(struct btrfs_path *path,
2483 struct new_sa_defrag_extent *new)
2484 {
2485 struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb);
2486 struct old_sa_defrag_extent *old, *tmp;
2487 int ret;
2488
2489 new->path = path;
2490
2491 list_for_each_entry_safe(old, tmp, &new->head, list) {
2492 ret = iterate_inodes_from_logical(old->bytenr +
2493 old->extent_offset, fs_info,
2494 path, record_one_backref,
2495 old, false);
2496 if (ret < 0 && ret != -ENOENT)
2497 return false;
2498
2499 /* no backref to be processed for this extent */
2500 if (!old->count) {
2501 list_del(&old->list);
2502 kfree(old);
2503 }
2504 }
2505
2506 if (list_empty(&new->head))
2507 return false;
2508
2509 return true;
2510 }
2511
2512 static int relink_is_mergable(struct extent_buffer *leaf,
2513 struct btrfs_file_extent_item *fi,
2514 struct new_sa_defrag_extent *new)
2515 {
2516 if (btrfs_file_extent_disk_bytenr(leaf, fi) != new->bytenr)
2517 return 0;
2518
2519 if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG)
2520 return 0;
2521
2522 if (btrfs_file_extent_compression(leaf, fi) != new->compress_type)
2523 return 0;
2524
2525 if (btrfs_file_extent_encryption(leaf, fi) ||
2526 btrfs_file_extent_other_encoding(leaf, fi))
2527 return 0;
2528
2529 return 1;
2530 }
2531
2532 /*
2533 * Note the backref might has changed, and in this case we just return 0.
2534 */
2535 static noinline int relink_extent_backref(struct btrfs_path *path,
2536 struct sa_defrag_extent_backref *prev,
2537 struct sa_defrag_extent_backref *backref)
2538 {
2539 struct btrfs_file_extent_item *extent;
2540 struct btrfs_file_extent_item *item;
2541 struct btrfs_ordered_extent *ordered;
2542 struct btrfs_trans_handle *trans;
2543 struct btrfs_root *root;
2544 struct btrfs_key key;
2545 struct extent_buffer *leaf;
2546 struct old_sa_defrag_extent *old = backref->old;
2547 struct new_sa_defrag_extent *new = old->new;
2548 struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb);
2549 struct inode *inode;
2550 struct extent_state *cached = NULL;
2551 int ret = 0;
2552 u64 start;
2553 u64 len;
2554 u64 lock_start;
2555 u64 lock_end;
2556 bool merge = false;
2557 int index;
2558
2559 if (prev && prev->root_id == backref->root_id &&
2560 prev->inum == backref->inum &&
2561 prev->file_pos + prev->num_bytes == backref->file_pos)
2562 merge = true;
2563
2564 /* step 1: get root */
2565 key.objectid = backref->root_id;
2566 key.type = BTRFS_ROOT_ITEM_KEY;
2567 key.offset = (u64)-1;
2568
2569 index = srcu_read_lock(&fs_info->subvol_srcu);
2570
2571 root = btrfs_read_fs_root_no_name(fs_info, &key);
2572 if (IS_ERR(root)) {
2573 srcu_read_unlock(&fs_info->subvol_srcu, index);
2574 if (PTR_ERR(root) == -ENOENT)
2575 return 0;
2576 return PTR_ERR(root);
2577 }
2578
2579 if (btrfs_root_readonly(root)) {
2580 srcu_read_unlock(&fs_info->subvol_srcu, index);
2581 return 0;
2582 }
2583
2584 /* step 2: get inode */
2585 key.objectid = backref->inum;
2586 key.type = BTRFS_INODE_ITEM_KEY;
2587 key.offset = 0;
2588
2589 inode = btrfs_iget(fs_info->sb, &key, root, NULL);
2590 if (IS_ERR(inode)) {
2591 srcu_read_unlock(&fs_info->subvol_srcu, index);
2592 return 0;
2593 }
2594
2595 srcu_read_unlock(&fs_info->subvol_srcu, index);
2596
2597 /* step 3: relink backref */
2598 lock_start = backref->file_pos;
2599 lock_end = backref->file_pos + backref->num_bytes - 1;
2600 lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2601 &cached);
2602
2603 ordered = btrfs_lookup_first_ordered_extent(inode, lock_end);
2604 if (ordered) {
2605 btrfs_put_ordered_extent(ordered);
2606 goto out_unlock;
2607 }
2608
2609 trans = btrfs_join_transaction(root);
2610 if (IS_ERR(trans)) {
2611 ret = PTR_ERR(trans);
2612 goto out_unlock;
2613 }
2614
2615 key.objectid = backref->inum;
2616 key.type = BTRFS_EXTENT_DATA_KEY;
2617 key.offset = backref->file_pos;
2618
2619 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2620 if (ret < 0) {
2621 goto out_free_path;
2622 } else if (ret > 0) {
2623 ret = 0;
2624 goto out_free_path;
2625 }
2626
2627 extent = btrfs_item_ptr(path->nodes[0], path->slots[0],
2628 struct btrfs_file_extent_item);
2629
2630 if (btrfs_file_extent_generation(path->nodes[0], extent) !=
2631 backref->generation)
2632 goto out_free_path;
2633
2634 btrfs_release_path(path);
2635
2636 start = backref->file_pos;
2637 if (backref->extent_offset < old->extent_offset + old->offset)
2638 start += old->extent_offset + old->offset -
2639 backref->extent_offset;
2640
2641 len = min(backref->extent_offset + backref->num_bytes,
2642 old->extent_offset + old->offset + old->len);
2643 len -= max(backref->extent_offset, old->extent_offset + old->offset);
2644
2645 ret = btrfs_drop_extents(trans, root, inode, start,
2646 start + len, 1);
2647 if (ret)
2648 goto out_free_path;
2649 again:
2650 key.objectid = btrfs_ino(BTRFS_I(inode));
2651 key.type = BTRFS_EXTENT_DATA_KEY;
2652 key.offset = start;
2653
2654 path->leave_spinning = 1;
2655 if (merge) {
2656 struct btrfs_file_extent_item *fi;
2657 u64 extent_len;
2658 struct btrfs_key found_key;
2659
2660 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2661 if (ret < 0)
2662 goto out_free_path;
2663
2664 path->slots[0]--;
2665 leaf = path->nodes[0];
2666 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2667
2668 fi = btrfs_item_ptr(leaf, path->slots[0],
2669 struct btrfs_file_extent_item);
2670 extent_len = btrfs_file_extent_num_bytes(leaf, fi);
2671
2672 if (extent_len + found_key.offset == start &&
2673 relink_is_mergable(leaf, fi, new)) {
2674 btrfs_set_file_extent_num_bytes(leaf, fi,
2675 extent_len + len);
2676 btrfs_mark_buffer_dirty(leaf);
2677 inode_add_bytes(inode, len);
2678
2679 ret = 1;
2680 goto out_free_path;
2681 } else {
2682 merge = false;
2683 btrfs_release_path(path);
2684 goto again;
2685 }
2686 }
2687
2688 ret = btrfs_insert_empty_item(trans, root, path, &key,
2689 sizeof(*extent));
2690 if (ret) {
2691 btrfs_abort_transaction(trans, ret);
2692 goto out_free_path;
2693 }
2694
2695 leaf = path->nodes[0];
2696 item = btrfs_item_ptr(leaf, path->slots[0],
2697 struct btrfs_file_extent_item);
2698 btrfs_set_file_extent_disk_bytenr(leaf, item, new->bytenr);
2699 btrfs_set_file_extent_disk_num_bytes(leaf, item, new->disk_len);
2700 btrfs_set_file_extent_offset(leaf, item, start - new->file_pos);
2701 btrfs_set_file_extent_num_bytes(leaf, item, len);
2702 btrfs_set_file_extent_ram_bytes(leaf, item, new->len);
2703 btrfs_set_file_extent_generation(leaf, item, trans->transid);
2704 btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG);
2705 btrfs_set_file_extent_compression(leaf, item, new->compress_type);
2706 btrfs_set_file_extent_encryption(leaf, item, 0);
2707 btrfs_set_file_extent_other_encoding(leaf, item, 0);
2708
2709 btrfs_mark_buffer_dirty(leaf);
2710 inode_add_bytes(inode, len);
2711 btrfs_release_path(path);
2712
2713 ret = btrfs_inc_extent_ref(trans, root, new->bytenr,
2714 new->disk_len, 0,
2715 backref->root_id, backref->inum,
2716 new->file_pos); /* start - extent_offset */
2717 if (ret) {
2718 btrfs_abort_transaction(trans, ret);
2719 goto out_free_path;
2720 }
2721
2722 ret = 1;
2723 out_free_path:
2724 btrfs_release_path(path);
2725 path->leave_spinning = 0;
2726 btrfs_end_transaction(trans);
2727 out_unlock:
2728 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lock_start, lock_end,
2729 &cached);
2730 iput(inode);
2731 return ret;
2732 }
2733
2734 static void free_sa_defrag_extent(struct new_sa_defrag_extent *new)
2735 {
2736 struct old_sa_defrag_extent *old, *tmp;
2737
2738 if (!new)
2739 return;
2740
2741 list_for_each_entry_safe(old, tmp, &new->head, list) {
2742 kfree(old);
2743 }
2744 kfree(new);
2745 }
2746
2747 static void relink_file_extents(struct new_sa_defrag_extent *new)
2748 {
2749 struct btrfs_fs_info *fs_info = btrfs_sb(new->inode->i_sb);
2750 struct btrfs_path *path;
2751 struct sa_defrag_extent_backref *backref;
2752 struct sa_defrag_extent_backref *prev = NULL;
2753 struct inode *inode;
2754 struct rb_node *node;
2755 int ret;
2756
2757 inode = new->inode;
2758
2759 path = btrfs_alloc_path();
2760 if (!path)
2761 return;
2762
2763 if (!record_extent_backrefs(path, new)) {
2764 btrfs_free_path(path);
2765 goto out;
2766 }
2767 btrfs_release_path(path);
2768
2769 while (1) {
2770 node = rb_first(&new->root);
2771 if (!node)
2772 break;
2773 rb_erase(node, &new->root);
2774
2775 backref = rb_entry(node, struct sa_defrag_extent_backref, node);
2776
2777 ret = relink_extent_backref(path, prev, backref);
2778 WARN_ON(ret < 0);
2779
2780 kfree(prev);
2781
2782 if (ret == 1)
2783 prev = backref;
2784 else
2785 prev = NULL;
2786 cond_resched();
2787 }
2788 kfree(prev);
2789
2790 btrfs_free_path(path);
2791 out:
2792 free_sa_defrag_extent(new);
2793
2794 atomic_dec(&fs_info->defrag_running);
2795 wake_up(&fs_info->transaction_wait);
2796 }
2797
2798 static struct new_sa_defrag_extent *
2799 record_old_file_extents(struct inode *inode,
2800 struct btrfs_ordered_extent *ordered)
2801 {
2802 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2803 struct btrfs_root *root = BTRFS_I(inode)->root;
2804 struct btrfs_path *path;
2805 struct btrfs_key key;
2806 struct old_sa_defrag_extent *old;
2807 struct new_sa_defrag_extent *new;
2808 int ret;
2809
2810 new = kmalloc(sizeof(*new), GFP_NOFS);
2811 if (!new)
2812 return NULL;
2813
2814 new->inode = inode;
2815 new->file_pos = ordered->file_offset;
2816 new->len = ordered->len;
2817 new->bytenr = ordered->start;
2818 new->disk_len = ordered->disk_len;
2819 new->compress_type = ordered->compress_type;
2820 new->root = RB_ROOT;
2821 INIT_LIST_HEAD(&new->head);
2822
2823 path = btrfs_alloc_path();
2824 if (!path)
2825 goto out_kfree;
2826
2827 key.objectid = btrfs_ino(BTRFS_I(inode));
2828 key.type = BTRFS_EXTENT_DATA_KEY;
2829 key.offset = new->file_pos;
2830
2831 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2832 if (ret < 0)
2833 goto out_free_path;
2834 if (ret > 0 && path->slots[0] > 0)
2835 path->slots[0]--;
2836
2837 /* find out all the old extents for the file range */
2838 while (1) {
2839 struct btrfs_file_extent_item *extent;
2840 struct extent_buffer *l;
2841 int slot;
2842 u64 num_bytes;
2843 u64 offset;
2844 u64 end;
2845 u64 disk_bytenr;
2846 u64 extent_offset;
2847
2848 l = path->nodes[0];
2849 slot = path->slots[0];
2850
2851 if (slot >= btrfs_header_nritems(l)) {
2852 ret = btrfs_next_leaf(root, path);
2853 if (ret < 0)
2854 goto out_free_path;
2855 else if (ret > 0)
2856 break;
2857 continue;
2858 }
2859
2860 btrfs_item_key_to_cpu(l, &key, slot);
2861
2862 if (key.objectid != btrfs_ino(BTRFS_I(inode)))
2863 break;
2864 if (key.type != BTRFS_EXTENT_DATA_KEY)
2865 break;
2866 if (key.offset >= new->file_pos + new->len)
2867 break;
2868
2869 extent = btrfs_item_ptr(l, slot, struct btrfs_file_extent_item);
2870
2871 num_bytes = btrfs_file_extent_num_bytes(l, extent);
2872 if (key.offset + num_bytes < new->file_pos)
2873 goto next;
2874
2875 disk_bytenr = btrfs_file_extent_disk_bytenr(l, extent);
2876 if (!disk_bytenr)
2877 goto next;
2878
2879 extent_offset = btrfs_file_extent_offset(l, extent);
2880
2881 old = kmalloc(sizeof(*old), GFP_NOFS);
2882 if (!old)
2883 goto out_free_path;
2884
2885 offset = max(new->file_pos, key.offset);
2886 end = min(new->file_pos + new->len, key.offset + num_bytes);
2887
2888 old->bytenr = disk_bytenr;
2889 old->extent_offset = extent_offset;
2890 old->offset = offset - key.offset;
2891 old->len = end - offset;
2892 old->new = new;
2893 old->count = 0;
2894 list_add_tail(&old->list, &new->head);
2895 next:
2896 path->slots[0]++;
2897 cond_resched();
2898 }
2899
2900 btrfs_free_path(path);
2901 atomic_inc(&fs_info->defrag_running);
2902
2903 return new;
2904
2905 out_free_path:
2906 btrfs_free_path(path);
2907 out_kfree:
2908 free_sa_defrag_extent(new);
2909 return NULL;
2910 }
2911
2912 static void btrfs_release_delalloc_bytes(struct btrfs_fs_info *fs_info,
2913 u64 start, u64 len)
2914 {
2915 struct btrfs_block_group_cache *cache;
2916
2917 cache = btrfs_lookup_block_group(fs_info, start);
2918 ASSERT(cache);
2919
2920 spin_lock(&cache->lock);
2921 cache->delalloc_bytes -= len;
2922 spin_unlock(&cache->lock);
2923
2924 btrfs_put_block_group(cache);
2925 }
2926
2927 /* as ordered data IO finishes, this gets called so we can finish
2928 * an ordered extent if the range of bytes in the file it covers are
2929 * fully written.
2930 */
2931 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
2932 {
2933 struct inode *inode = ordered_extent->inode;
2934 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2935 struct btrfs_root *root = BTRFS_I(inode)->root;
2936 struct btrfs_trans_handle *trans = NULL;
2937 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2938 struct extent_state *cached_state = NULL;
2939 struct new_sa_defrag_extent *new = NULL;
2940 int compress_type = 0;
2941 int ret = 0;
2942 u64 logical_len = ordered_extent->len;
2943 bool nolock;
2944 bool truncated = false;
2945 bool range_locked = false;
2946 bool clear_new_delalloc_bytes = false;
2947
2948 if (!test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) &&
2949 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags) &&
2950 !test_bit(BTRFS_ORDERED_DIRECT, &ordered_extent->flags))
2951 clear_new_delalloc_bytes = true;
2952
2953 nolock = btrfs_is_free_space_inode(BTRFS_I(inode));
2954
2955 if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) {
2956 ret = -EIO;
2957 goto out;
2958 }
2959
2960 btrfs_free_io_failure_record(BTRFS_I(inode),
2961 ordered_extent->file_offset,
2962 ordered_extent->file_offset +
2963 ordered_extent->len - 1);
2964
2965 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) {
2966 truncated = true;
2967 logical_len = ordered_extent->truncated_len;
2968 /* Truncated the entire extent, don't bother adding */
2969 if (!logical_len)
2970 goto out;
2971 }
2972
2973 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
2974 BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */
2975
2976 /*
2977 * For mwrite(mmap + memset to write) case, we still reserve
2978 * space for NOCOW range.
2979 * As NOCOW won't cause a new delayed ref, just free the space
2980 */
2981 btrfs_qgroup_free_data(inode, NULL, ordered_extent->file_offset,
2982 ordered_extent->len);
2983 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
2984 if (nolock)
2985 trans = btrfs_join_transaction_nolock(root);
2986 else
2987 trans = btrfs_join_transaction(root);
2988 if (IS_ERR(trans)) {
2989 ret = PTR_ERR(trans);
2990 trans = NULL;
2991 goto out;
2992 }
2993 trans->block_rsv = &BTRFS_I(inode)->block_rsv;
2994 ret = btrfs_update_inode_fallback(trans, root, inode);
2995 if (ret) /* -ENOMEM or corruption */
2996 btrfs_abort_transaction(trans, ret);
2997 goto out;
2998 }
2999
3000 range_locked = true;
3001 lock_extent_bits(io_tree, ordered_extent->file_offset,
3002 ordered_extent->file_offset + ordered_extent->len - 1,
3003 &cached_state);
3004
3005 ret = test_range_bit(io_tree, ordered_extent->file_offset,
3006 ordered_extent->file_offset + ordered_extent->len - 1,
3007 EXTENT_DEFRAG, 0, cached_state);
3008 if (ret) {
3009 u64 last_snapshot = btrfs_root_last_snapshot(&root->root_item);
3010 if (0 && last_snapshot >= BTRFS_I(inode)->generation)
3011 /* the inode is shared */
3012 new = record_old_file_extents(inode, ordered_extent);
3013
3014 clear_extent_bit(io_tree, ordered_extent->file_offset,
3015 ordered_extent->file_offset + ordered_extent->len - 1,
3016 EXTENT_DEFRAG, 0, 0, &cached_state);
3017 }
3018
3019 if (nolock)
3020 trans = btrfs_join_transaction_nolock(root);
3021 else
3022 trans = btrfs_join_transaction(root);
3023 if (IS_ERR(trans)) {
3024 ret = PTR_ERR(trans);
3025 trans = NULL;
3026 goto out;
3027 }
3028
3029 trans->block_rsv = &BTRFS_I(inode)->block_rsv;
3030
3031 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
3032 compress_type = ordered_extent->compress_type;
3033 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
3034 BUG_ON(compress_type);
3035 btrfs_qgroup_free_data(inode, NULL, ordered_extent->file_offset,
3036 ordered_extent->len);
3037 ret = btrfs_mark_extent_written(trans, BTRFS_I(inode),
3038 ordered_extent->file_offset,
3039 ordered_extent->file_offset +
3040 logical_len);
3041 } else {
3042 BUG_ON(root == fs_info->tree_root);
3043 ret = insert_reserved_file_extent(trans, inode,
3044 ordered_extent->file_offset,
3045 ordered_extent->start,
3046 ordered_extent->disk_len,
3047 logical_len, logical_len,
3048 compress_type, 0, 0,
3049 BTRFS_FILE_EXTENT_REG);
3050 if (!ret)
3051 btrfs_release_delalloc_bytes(fs_info,
3052 ordered_extent->start,
3053 ordered_extent->disk_len);
3054 }
3055 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
3056 ordered_extent->file_offset, ordered_extent->len,
3057 trans->transid);
3058 if (ret < 0) {
3059 btrfs_abort_transaction(trans, ret);
3060 goto out;
3061 }
3062
3063 ret = add_pending_csums(trans, inode, &ordered_extent->list);
3064 if (ret) {
3065 btrfs_abort_transaction(trans, ret);
3066 goto out;
3067 }
3068
3069 btrfs_ordered_update_i_size(inode, 0, ordered_extent);
3070 ret = btrfs_update_inode_fallback(trans, root, inode);
3071 if (ret) { /* -ENOMEM or corruption */
3072 btrfs_abort_transaction(trans, ret);
3073 goto out;
3074 }
3075 ret = 0;
3076 out:
3077 if (range_locked || clear_new_delalloc_bytes) {
3078 unsigned int clear_bits = 0;
3079
3080 if (range_locked)
3081 clear_bits |= EXTENT_LOCKED;
3082 if (clear_new_delalloc_bytes)
3083 clear_bits |= EXTENT_DELALLOC_NEW;
3084 clear_extent_bit(&BTRFS_I(inode)->io_tree,
3085 ordered_extent->file_offset,
3086 ordered_extent->file_offset +
3087 ordered_extent->len - 1,
3088 clear_bits,
3089 (clear_bits & EXTENT_LOCKED) ? 1 : 0,
3090 0, &cached_state);
3091 }
3092
3093 if (trans)
3094 btrfs_end_transaction(trans);
3095
3096 if (ret || truncated) {
3097 u64 start, end;
3098
3099 if (truncated)
3100 start = ordered_extent->file_offset + logical_len;
3101 else
3102 start = ordered_extent->file_offset;
3103 end = ordered_extent->file_offset + ordered_extent->len - 1;
3104 clear_extent_uptodate(io_tree, start, end, NULL);
3105
3106 /* Drop the cache for the part of the extent we didn't write. */
3107 btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 0);
3108
3109 /*
3110 * If the ordered extent had an IOERR or something else went
3111 * wrong we need to return the space for this ordered extent
3112 * back to the allocator. We only free the extent in the
3113 * truncated case if we didn't write out the extent at all.
3114 */
3115 if ((ret || !logical_len) &&
3116 !test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) &&
3117 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags))
3118 btrfs_free_reserved_extent(fs_info,
3119 ordered_extent->start,
3120 ordered_extent->disk_len, 1);
3121 }
3122
3123
3124 /*
3125 * This needs to be done to make sure anybody waiting knows we are done
3126 * updating everything for this ordered extent.
3127 */
3128 btrfs_remove_ordered_extent(inode, ordered_extent);
3129
3130 /* for snapshot-aware defrag */
3131 if (new) {
3132 if (ret) {
3133 free_sa_defrag_extent(new);
3134 atomic_dec(&fs_info->defrag_running);
3135 } else {
3136 relink_file_extents(new);
3137 }
3138 }
3139
3140 /* once for us */
3141 btrfs_put_ordered_extent(ordered_extent);
3142 /* once for the tree */
3143 btrfs_put_ordered_extent(ordered_extent);
3144
3145 /* Try to release some metadata so we don't get an OOM but don't wait */
3146 btrfs_btree_balance_dirty_nodelay(fs_info);
3147
3148 return ret;
3149 }
3150
3151 static void finish_ordered_fn(struct btrfs_work *work)
3152 {
3153 struct btrfs_ordered_extent *ordered_extent;
3154 ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
3155 btrfs_finish_ordered_io(ordered_extent);
3156 }
3157
3158 static void btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
3159 struct extent_state *state, int uptodate)
3160 {
3161 struct inode *inode = page->mapping->host;
3162 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3163 struct btrfs_ordered_extent *ordered_extent = NULL;
3164 struct btrfs_workqueue *wq;
3165 btrfs_work_func_t func;
3166
3167 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate);
3168
3169 ClearPagePrivate2(page);
3170 if (!btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
3171 end - start + 1, uptodate))
3172 return;
3173
3174 if (btrfs_is_free_space_inode(BTRFS_I(inode))) {
3175 wq = fs_info->endio_freespace_worker;
3176 func = btrfs_freespace_write_helper;
3177 } else {
3178 wq = fs_info->endio_write_workers;
3179 func = btrfs_endio_write_helper;
3180 }
3181
3182 btrfs_init_work(&ordered_extent->work, func, finish_ordered_fn, NULL,
3183 NULL);
3184 btrfs_queue_work(wq, &ordered_extent->work);
3185 }
3186
3187 static int __readpage_endio_check(struct inode *inode,
3188 struct btrfs_io_bio *io_bio,
3189 int icsum, struct page *page,
3190 int pgoff, u64 start, size_t len)
3191 {
3192 char *kaddr;
3193 u32 csum_expected;
3194 u32 csum = ~(u32)0;
3195
3196 csum_expected = *(((u32 *)io_bio->csum) + icsum);
3197
3198 kaddr = kmap_atomic(page);
3199 csum = btrfs_csum_data(kaddr + pgoff, csum, len);
3200 btrfs_csum_final(csum, (u8 *)&csum);
3201 if (csum != csum_expected)
3202 goto zeroit;
3203
3204 kunmap_atomic(kaddr);
3205 return 0;
3206 zeroit:
3207 btrfs_print_data_csum_error(BTRFS_I(inode), start, csum, csum_expected,
3208 io_bio->mirror_num);
3209 memset(kaddr + pgoff, 1, len);
3210 flush_dcache_page(page);
3211 kunmap_atomic(kaddr);
3212 return -EIO;
3213 }
3214
3215 /*
3216 * when reads are done, we need to check csums to verify the data is correct
3217 * if there's a match, we allow the bio to finish. If not, the code in
3218 * extent_io.c will try to find good copies for us.
3219 */
3220 static int btrfs_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
3221 u64 phy_offset, struct page *page,
3222 u64 start, u64 end, int mirror)
3223 {
3224 size_t offset = start - page_offset(page);
3225 struct inode *inode = page->mapping->host;
3226 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3227 struct btrfs_root *root = BTRFS_I(inode)->root;
3228
3229 if (PageChecked(page)) {
3230 ClearPageChecked(page);
3231 return 0;
3232 }
3233
3234 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
3235 return 0;
3236
3237 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
3238 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
3239 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM);
3240 return 0;
3241 }
3242
3243 phy_offset >>= inode->i_sb->s_blocksize_bits;
3244 return __readpage_endio_check(inode, io_bio, phy_offset, page, offset,
3245 start, (size_t)(end - start + 1));
3246 }
3247
3248 /*
3249 * btrfs_add_delayed_iput - perform a delayed iput on @inode
3250 *
3251 * @inode: The inode we want to perform iput on
3252 *
3253 * This function uses the generic vfs_inode::i_count to track whether we should
3254 * just decrement it (in case it's > 1) or if this is the last iput then link
3255 * the inode to the delayed iput machinery. Delayed iputs are processed at
3256 * transaction commit time/superblock commit/cleaner kthread.
3257 */
3258 void btrfs_add_delayed_iput(struct inode *inode)
3259 {
3260 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3261 struct btrfs_inode *binode = BTRFS_I(inode);
3262
3263 if (atomic_add_unless(&inode->i_count, -1, 1))
3264 return;
3265
3266 spin_lock(&fs_info->delayed_iput_lock);
3267 ASSERT(list_empty(&binode->delayed_iput));
3268 list_add_tail(&binode->delayed_iput, &fs_info->delayed_iputs);
3269 spin_unlock(&fs_info->delayed_iput_lock);
3270 }
3271
3272 void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info)
3273 {
3274
3275 spin_lock(&fs_info->delayed_iput_lock);
3276 while (!list_empty(&fs_info->delayed_iputs)) {
3277 struct btrfs_inode *inode;
3278
3279 inode = list_first_entry(&fs_info->delayed_iputs,
3280 struct btrfs_inode, delayed_iput);
3281 list_del_init(&inode->delayed_iput);
3282 spin_unlock(&fs_info->delayed_iput_lock);
3283 iput(&inode->vfs_inode);
3284 spin_lock(&fs_info->delayed_iput_lock);
3285 }
3286 spin_unlock(&fs_info->delayed_iput_lock);
3287 }
3288
3289 /*
3290 * This creates an orphan entry for the given inode in case something goes wrong
3291 * in the middle of an unlink.
3292 */
3293 int btrfs_orphan_add(struct btrfs_trans_handle *trans,
3294 struct btrfs_inode *inode)
3295 {
3296 int ret;
3297
3298 ret = btrfs_insert_orphan_item(trans, inode->root, btrfs_ino(inode));
3299 if (ret && ret != -EEXIST) {
3300 btrfs_abort_transaction(trans, ret);
3301 return ret;
3302 }
3303
3304 return 0;
3305 }
3306
3307 /*
3308 * We have done the delete so we can go ahead and remove the orphan item for
3309 * this particular inode.
3310 */
3311 static int btrfs_orphan_del(struct btrfs_trans_handle *trans,
3312 struct btrfs_inode *inode)
3313 {
3314 return btrfs_del_orphan_item(trans, inode->root, btrfs_ino(inode));
3315 }
3316
3317 /*
3318 * this cleans up any orphans that may be left on the list from the last use
3319 * of this root.
3320 */
3321 int btrfs_orphan_cleanup(struct btrfs_root *root)
3322 {
3323 struct btrfs_fs_info *fs_info = root->fs_info;
3324 struct btrfs_path *path;
3325 struct extent_buffer *leaf;
3326 struct btrfs_key key, found_key;
3327 struct btrfs_trans_handle *trans;
3328 struct inode *inode;
3329 u64 last_objectid = 0;
3330 int ret = 0, nr_unlink = 0;
3331
3332 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
3333 return 0;
3334
3335 path = btrfs_alloc_path();
3336 if (!path) {
3337 ret = -ENOMEM;
3338 goto out;
3339 }
3340 path->reada = READA_BACK;
3341
3342 key.objectid = BTRFS_ORPHAN_OBJECTID;
3343 key.type = BTRFS_ORPHAN_ITEM_KEY;
3344 key.offset = (u64)-1;
3345
3346 while (1) {
3347 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3348 if (ret < 0)
3349 goto out;
3350
3351 /*
3352 * if ret == 0 means we found what we were searching for, which
3353 * is weird, but possible, so only screw with path if we didn't
3354 * find the key and see if we have stuff that matches
3355 */
3356 if (ret > 0) {
3357 ret = 0;
3358 if (path->slots[0] == 0)
3359 break;
3360 path->slots[0]--;
3361 }
3362
3363 /* pull out the item */
3364 leaf = path->nodes[0];
3365 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3366
3367 /* make sure the item matches what we want */
3368 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
3369 break;
3370 if (found_key.type != BTRFS_ORPHAN_ITEM_KEY)
3371 break;
3372
3373 /* release the path since we're done with it */
3374 btrfs_release_path(path);
3375
3376 /*
3377 * this is where we are basically btrfs_lookup, without the
3378 * crossing root thing. we store the inode number in the
3379 * offset of the orphan item.
3380 */
3381
3382 if (found_key.offset == last_objectid) {
3383 btrfs_err(fs_info,
3384 "Error removing orphan entry, stopping orphan cleanup");
3385 ret = -EINVAL;
3386 goto out;
3387 }
3388
3389 last_objectid = found_key.offset;
3390
3391 found_key.objectid = found_key.offset;
3392 found_key.type = BTRFS_INODE_ITEM_KEY;
3393 found_key.offset = 0;
3394 inode = btrfs_iget(fs_info->sb, &found_key, root, NULL);
3395 ret = PTR_ERR_OR_ZERO(inode);
3396 if (ret && ret != -ENOENT)
3397 goto out;
3398
3399 if (ret == -ENOENT && root == fs_info->tree_root) {
3400 struct btrfs_root *dead_root;
3401 struct btrfs_fs_info *fs_info = root->fs_info;
3402 int is_dead_root = 0;
3403
3404 /*
3405 * this is an orphan in the tree root. Currently these
3406 * could come from 2 sources:
3407 * a) a snapshot deletion in progress
3408 * b) a free space cache inode
3409 * We need to distinguish those two, as the snapshot
3410 * orphan must not get deleted.
3411 * find_dead_roots already ran before us, so if this
3412 * is a snapshot deletion, we should find the root
3413 * in the dead_roots list
3414 */
3415 spin_lock(&fs_info->trans_lock);
3416 list_for_each_entry(dead_root, &fs_info->dead_roots,
3417 root_list) {
3418 if (dead_root->root_key.objectid ==
3419 found_key.objectid) {
3420 is_dead_root = 1;
3421 break;
3422 }
3423 }
3424 spin_unlock(&fs_info->trans_lock);
3425 if (is_dead_root) {
3426 /* prevent this orphan from being found again */
3427 key.offset = found_key.objectid - 1;
3428 continue;
3429 }
3430
3431 }
3432
3433 /*
3434 * If we have an inode with links, there are a couple of
3435 * possibilities. Old kernels (before v3.12) used to create an
3436 * orphan item for truncate indicating that there were possibly
3437 * extent items past i_size that needed to be deleted. In v3.12,
3438 * truncate was changed to update i_size in sync with the extent
3439 * items, but the (useless) orphan item was still created. Since
3440 * v4.18, we don't create the orphan item for truncate at all.
3441 *
3442 * So, this item could mean that we need to do a truncate, but
3443 * only if this filesystem was last used on a pre-v3.12 kernel
3444 * and was not cleanly unmounted. The odds of that are quite
3445 * slim, and it's a pain to do the truncate now, so just delete
3446 * the orphan item.
3447 *
3448 * It's also possible that this orphan item was supposed to be
3449 * deleted but wasn't. The inode number may have been reused,
3450 * but either way, we can delete the orphan item.
3451 */
3452 if (ret == -ENOENT || inode->i_nlink) {
3453 if (!ret)
3454 iput(inode);
3455 trans = btrfs_start_transaction(root, 1);
3456 if (IS_ERR(trans)) {
3457 ret = PTR_ERR(trans);
3458 goto out;
3459 }
3460 btrfs_debug(fs_info, "auto deleting %Lu",
3461 found_key.objectid);
3462 ret = btrfs_del_orphan_item(trans, root,
3463 found_key.objectid);
3464 btrfs_end_transaction(trans);
3465 if (ret)
3466 goto out;
3467 continue;
3468 }
3469
3470 nr_unlink++;
3471
3472 /* this will do delete_inode and everything for us */
3473 iput(inode);
3474 if (ret)
3475 goto out;
3476 }
3477 /* release the path since we're done with it */
3478 btrfs_release_path(path);
3479
3480 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
3481
3482 if (test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state)) {
3483 trans = btrfs_join_transaction(root);
3484 if (!IS_ERR(trans))
3485 btrfs_end_transaction(trans);
3486 }
3487
3488 if (nr_unlink)
3489 btrfs_debug(fs_info, "unlinked %d orphans", nr_unlink);
3490
3491 out:
3492 if (ret)
3493 btrfs_err(fs_info, "could not do orphan cleanup %d", ret);
3494 btrfs_free_path(path);
3495 return ret;
3496 }
3497
3498 /*
3499 * very simple check to peek ahead in the leaf looking for xattrs. If we
3500 * don't find any xattrs, we know there can't be any acls.
3501 *
3502 * slot is the slot the inode is in, objectid is the objectid of the inode
3503 */
3504 static noinline int acls_after_inode_item(struct extent_buffer *leaf,
3505 int slot, u64 objectid,
3506 int *first_xattr_slot)
3507 {
3508 u32 nritems = btrfs_header_nritems(leaf);
3509 struct btrfs_key found_key;
3510 static u64 xattr_access = 0;
3511 static u64 xattr_default = 0;
3512 int scanned = 0;
3513
3514 if (!xattr_access) {
3515 xattr_access = btrfs_name_hash(XATTR_NAME_POSIX_ACL_ACCESS,
3516 strlen(XATTR_NAME_POSIX_ACL_ACCESS));
3517 xattr_default = btrfs_name_hash(XATTR_NAME_POSIX_ACL_DEFAULT,
3518 strlen(XATTR_NAME_POSIX_ACL_DEFAULT));
3519 }
3520
3521 slot++;
3522 *first_xattr_slot = -1;
3523 while (slot < nritems) {
3524 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3525
3526 /* we found a different objectid, there must not be acls */
3527 if (found_key.objectid != objectid)
3528 return 0;
3529
3530 /* we found an xattr, assume we've got an acl */
3531 if (found_key.type == BTRFS_XATTR_ITEM_KEY) {
3532 if (*first_xattr_slot == -1)
3533 *first_xattr_slot = slot;
3534 if (found_key.offset == xattr_access ||
3535 found_key.offset == xattr_default)
3536 return 1;
3537 }
3538
3539 /*
3540 * we found a key greater than an xattr key, there can't
3541 * be any acls later on
3542 */
3543 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
3544 return 0;
3545
3546 slot++;
3547 scanned++;
3548
3549 /*
3550 * it goes inode, inode backrefs, xattrs, extents,
3551 * so if there are a ton of hard links to an inode there can
3552 * be a lot of backrefs. Don't waste time searching too hard,
3553 * this is just an optimization
3554 */
3555 if (scanned >= 8)
3556 break;
3557 }
3558 /* we hit the end of the leaf before we found an xattr or
3559 * something larger than an xattr. We have to assume the inode
3560 * has acls
3561 */
3562 if (*first_xattr_slot == -1)
3563 *first_xattr_slot = slot;
3564 return 1;
3565 }
3566
3567 /*
3568 * read an inode from the btree into the in-memory inode
3569 */
3570 static int btrfs_read_locked_inode(struct inode *inode)
3571 {
3572 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3573 struct btrfs_path *path;
3574 struct extent_buffer *leaf;
3575 struct btrfs_inode_item *inode_item;
3576 struct btrfs_root *root = BTRFS_I(inode)->root;
3577 struct btrfs_key location;
3578 unsigned long ptr;
3579 int maybe_acls;
3580 u32 rdev;
3581 int ret;
3582 bool filled = false;
3583 int first_xattr_slot;
3584
3585 ret = btrfs_fill_inode(inode, &rdev);
3586 if (!ret)
3587 filled = true;
3588
3589 path = btrfs_alloc_path();
3590 if (!path)
3591 return -ENOMEM;
3592
3593 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
3594
3595 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
3596 if (ret) {
3597 btrfs_free_path(path);
3598 return ret;
3599 }
3600
3601 leaf = path->nodes[0];
3602
3603 if (filled)
3604 goto cache_index;
3605
3606 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3607 struct btrfs_inode_item);
3608 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
3609 set_nlink(inode, btrfs_inode_nlink(leaf, inode_item));
3610 i_uid_write(inode, btrfs_inode_uid(leaf, inode_item));
3611 i_gid_write(inode, btrfs_inode_gid(leaf, inode_item));
3612 btrfs_i_size_write(BTRFS_I(inode), btrfs_inode_size(leaf, inode_item));
3613
3614 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->atime);
3615 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->atime);
3616
3617 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->mtime);
3618 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->mtime);
3619
3620 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->ctime);
3621 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->ctime);
3622
3623 BTRFS_I(inode)->i_otime.tv_sec =
3624 btrfs_timespec_sec(leaf, &inode_item->otime);
3625 BTRFS_I(inode)->i_otime.tv_nsec =
3626 btrfs_timespec_nsec(leaf, &inode_item->otime);
3627
3628 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
3629 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
3630 BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item);
3631
3632 inode_set_iversion_queried(inode,
3633 btrfs_inode_sequence(leaf, inode_item));
3634 inode->i_generation = BTRFS_I(inode)->generation;
3635 inode->i_rdev = 0;
3636 rdev = btrfs_inode_rdev(leaf, inode_item);
3637
3638 BTRFS_I(inode)->index_cnt = (u64)-1;
3639 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
3640
3641 cache_index:
3642 /*
3643 * If we were modified in the current generation and evicted from memory
3644 * and then re-read we need to do a full sync since we don't have any
3645 * idea about which extents were modified before we were evicted from
3646 * cache.
3647 *
3648 * This is required for both inode re-read from disk and delayed inode
3649 * in delayed_nodes_tree.
3650 */
3651 if (BTRFS_I(inode)->last_trans == fs_info->generation)
3652 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3653 &BTRFS_I(inode)->runtime_flags);
3654
3655 /*
3656 * We don't persist the id of the transaction where an unlink operation
3657 * against the inode was last made. So here we assume the inode might
3658 * have been evicted, and therefore the exact value of last_unlink_trans
3659 * lost, and set it to last_trans to avoid metadata inconsistencies
3660 * between the inode and its parent if the inode is fsync'ed and the log
3661 * replayed. For example, in the scenario:
3662 *
3663 * touch mydir/foo
3664 * ln mydir/foo mydir/bar
3665 * sync
3666 * unlink mydir/bar
3667 * echo 2 > /proc/sys/vm/drop_caches # evicts inode
3668 * xfs_io -c fsync mydir/foo
3669 * <power failure>
3670 * mount fs, triggers fsync log replay
3671 *
3672 * We must make sure that when we fsync our inode foo we also log its
3673 * parent inode, otherwise after log replay the parent still has the
3674 * dentry with the "bar" name but our inode foo has a link count of 1
3675 * and doesn't have an inode ref with the name "bar" anymore.
3676 *
3677 * Setting last_unlink_trans to last_trans is a pessimistic approach,
3678 * but it guarantees correctness at the expense of occasional full
3679 * transaction commits on fsync if our inode is a directory, or if our
3680 * inode is not a directory, logging its parent unnecessarily.
3681 */
3682 BTRFS_I(inode)->last_unlink_trans = BTRFS_I(inode)->last_trans;
3683
3684 path->slots[0]++;
3685 if (inode->i_nlink != 1 ||
3686 path->slots[0] >= btrfs_header_nritems(leaf))
3687 goto cache_acl;
3688
3689 btrfs_item_key_to_cpu(leaf, &location, path->slots[0]);
3690 if (location.objectid != btrfs_ino(BTRFS_I(inode)))
3691 goto cache_acl;
3692
3693 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
3694 if (location.type == BTRFS_INODE_REF_KEY) {
3695 struct btrfs_inode_ref *ref;
3696
3697 ref = (struct btrfs_inode_ref *)ptr;
3698 BTRFS_I(inode)->dir_index = btrfs_inode_ref_index(leaf, ref);
3699 } else if (location.type == BTRFS_INODE_EXTREF_KEY) {
3700 struct btrfs_inode_extref *extref;
3701
3702 extref = (struct btrfs_inode_extref *)ptr;
3703 BTRFS_I(inode)->dir_index = btrfs_inode_extref_index(leaf,
3704 extref);
3705 }
3706 cache_acl:
3707 /*
3708 * try to precache a NULL acl entry for files that don't have
3709 * any xattrs or acls
3710 */
3711 maybe_acls = acls_after_inode_item(leaf, path->slots[0],
3712 btrfs_ino(BTRFS_I(inode)), &first_xattr_slot);
3713 if (first_xattr_slot != -1) {
3714 path->slots[0] = first_xattr_slot;
3715 ret = btrfs_load_inode_props(inode, path);
3716 if (ret)
3717 btrfs_err(fs_info,
3718 "error loading props for ino %llu (root %llu): %d",
3719 btrfs_ino(BTRFS_I(inode)),
3720 root->root_key.objectid, ret);
3721 }
3722 btrfs_free_path(path);
3723
3724 if (!maybe_acls)
3725 cache_no_acl(inode);
3726
3727 switch (inode->i_mode & S_IFMT) {
3728 case S_IFREG:
3729 inode->i_mapping->a_ops = &btrfs_aops;
3730 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
3731 inode->i_fop = &btrfs_file_operations;
3732 inode->i_op = &btrfs_file_inode_operations;
3733 break;
3734 case S_IFDIR:
3735 inode->i_fop = &btrfs_dir_file_operations;
3736 inode->i_op = &btrfs_dir_inode_operations;
3737 break;
3738 case S_IFLNK:
3739 inode->i_op = &btrfs_symlink_inode_operations;
3740 inode_nohighmem(inode);
3741 inode->i_mapping->a_ops = &btrfs_symlink_aops;
3742 break;
3743 default:
3744 inode->i_op = &btrfs_special_inode_operations;
3745 init_special_inode(inode, inode->i_mode, rdev);
3746 break;
3747 }
3748
3749 btrfs_sync_inode_flags_to_i_flags(inode);
3750 return 0;
3751 }
3752
3753 /*
3754 * given a leaf and an inode, copy the inode fields into the leaf
3755 */
3756 static void fill_inode_item(struct btrfs_trans_handle *trans,
3757 struct extent_buffer *leaf,
3758 struct btrfs_inode_item *item,
3759 struct inode *inode)
3760 {
3761 struct btrfs_map_token token;
3762
3763 btrfs_init_map_token(&token);
3764
3765 btrfs_set_token_inode_uid(leaf, item, i_uid_read(inode), &token);
3766 btrfs_set_token_inode_gid(leaf, item, i_gid_read(inode), &token);
3767 btrfs_set_token_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size,
3768 &token);
3769 btrfs_set_token_inode_mode(leaf, item, inode->i_mode, &token);
3770 btrfs_set_token_inode_nlink(leaf, item, inode->i_nlink, &token);
3771
3772 btrfs_set_token_timespec_sec(leaf, &item->atime,
3773 inode->i_atime.tv_sec, &token);
3774 btrfs_set_token_timespec_nsec(leaf, &item->atime,
3775 inode->i_atime.tv_nsec, &token);
3776
3777 btrfs_set_token_timespec_sec(leaf, &item->mtime,
3778 inode->i_mtime.tv_sec, &token);
3779 btrfs_set_token_timespec_nsec(leaf, &item->mtime,
3780 inode->i_mtime.tv_nsec, &token);
3781
3782 btrfs_set_token_timespec_sec(leaf, &item->ctime,
3783 inode->i_ctime.tv_sec, &token);
3784 btrfs_set_token_timespec_nsec(leaf, &item->ctime,
3785 inode->i_ctime.tv_nsec, &token);
3786
3787 btrfs_set_token_timespec_sec(leaf, &item->otime,
3788 BTRFS_I(inode)->i_otime.tv_sec, &token);
3789 btrfs_set_token_timespec_nsec(leaf, &item->otime,
3790 BTRFS_I(inode)->i_otime.tv_nsec, &token);
3791
3792 btrfs_set_token_inode_nbytes(leaf, item, inode_get_bytes(inode),
3793 &token);
3794 btrfs_set_token_inode_generation(leaf, item, BTRFS_I(inode)->generation,
3795 &token);
3796 btrfs_set_token_inode_sequence(leaf, item, inode_peek_iversion(inode),
3797 &token);
3798 btrfs_set_token_inode_transid(leaf, item, trans->transid, &token);
3799 btrfs_set_token_inode_rdev(leaf, item, inode->i_rdev, &token);
3800 btrfs_set_token_inode_flags(leaf, item, BTRFS_I(inode)->flags, &token);
3801 btrfs_set_token_inode_block_group(leaf, item, 0, &token);
3802 }
3803
3804 /*
3805 * copy everything in the in-memory inode into the btree.
3806 */
3807 static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans,
3808 struct btrfs_root *root, struct inode *inode)
3809 {
3810 struct btrfs_inode_item *inode_item;
3811 struct btrfs_path *path;
3812 struct extent_buffer *leaf;
3813 int ret;
3814
3815 path = btrfs_alloc_path();
3816 if (!path)
3817 return -ENOMEM;
3818
3819 path->leave_spinning = 1;
3820 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location,
3821 1);
3822 if (ret) {
3823 if (ret > 0)
3824 ret = -ENOENT;
3825 goto failed;
3826 }
3827
3828 leaf = path->nodes[0];
3829 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3830 struct btrfs_inode_item);
3831
3832 fill_inode_item(trans, leaf, inode_item, inode);
3833 btrfs_mark_buffer_dirty(leaf);
3834 btrfs_set_inode_last_trans(trans, inode);
3835 ret = 0;
3836 failed:
3837 btrfs_free_path(path);
3838 return ret;
3839 }
3840
3841 /*
3842 * copy everything in the in-memory inode into the btree.
3843 */
3844 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
3845 struct btrfs_root *root, struct inode *inode)
3846 {
3847 struct btrfs_fs_info *fs_info = root->fs_info;
3848 int ret;
3849
3850 /*
3851 * If the inode is a free space inode, we can deadlock during commit
3852 * if we put it into the delayed code.
3853 *
3854 * The data relocation inode should also be directly updated
3855 * without delay
3856 */
3857 if (!btrfs_is_free_space_inode(BTRFS_I(inode))
3858 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
3859 && !test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags)) {
3860 btrfs_update_root_times(trans, root);
3861
3862 ret = btrfs_delayed_update_inode(trans, root, inode);
3863 if (!ret)
3864 btrfs_set_inode_last_trans(trans, inode);
3865 return ret;
3866 }
3867
3868 return btrfs_update_inode_item(trans, root, inode);
3869 }
3870
3871 noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
3872 struct btrfs_root *root,
3873 struct inode *inode)
3874 {
3875 int ret;
3876
3877 ret = btrfs_update_inode(trans, root, inode);
3878 if (ret == -ENOSPC)
3879 return btrfs_update_inode_item(trans, root, inode);
3880 return ret;
3881 }
3882
3883 /*
3884 * unlink helper that gets used here in inode.c and in the tree logging
3885 * recovery code. It remove a link in a directory with a given name, and
3886 * also drops the back refs in the inode to the directory
3887 */
3888 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3889 struct btrfs_root *root,
3890 struct btrfs_inode *dir,
3891 struct btrfs_inode *inode,
3892 const char *name, int name_len)
3893 {
3894 struct btrfs_fs_info *fs_info = root->fs_info;
3895 struct btrfs_path *path;
3896 int ret = 0;
3897 struct extent_buffer *leaf;
3898 struct btrfs_dir_item *di;
3899 struct btrfs_key key;
3900 u64 index;
3901 u64 ino = btrfs_ino(inode);
3902 u64 dir_ino = btrfs_ino(dir);
3903
3904 path = btrfs_alloc_path();
3905 if (!path) {
3906 ret = -ENOMEM;
3907 goto out;
3908 }
3909
3910 path->leave_spinning = 1;
3911 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3912 name, name_len, -1);
3913 if (IS_ERR(di)) {
3914 ret = PTR_ERR(di);
3915 goto err;
3916 }
3917 if (!di) {
3918 ret = -ENOENT;
3919 goto err;
3920 }
3921 leaf = path->nodes[0];
3922 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3923 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3924 if (ret)
3925 goto err;
3926 btrfs_release_path(path);
3927
3928 /*
3929 * If we don't have dir index, we have to get it by looking up
3930 * the inode ref, since we get the inode ref, remove it directly,
3931 * it is unnecessary to do delayed deletion.
3932 *
3933 * But if we have dir index, needn't search inode ref to get it.
3934 * Since the inode ref is close to the inode item, it is better
3935 * that we delay to delete it, and just do this deletion when
3936 * we update the inode item.
3937 */
3938 if (inode->dir_index) {
3939 ret = btrfs_delayed_delete_inode_ref(inode);
3940 if (!ret) {
3941 index = inode->dir_index;
3942 goto skip_backref;
3943 }
3944 }
3945
3946 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino,
3947 dir_ino, &index);
3948 if (ret) {
3949 btrfs_info(fs_info,
3950 "failed to delete reference to %.*s, inode %llu parent %llu",
3951 name_len, name, ino, dir_ino);
3952 btrfs_abort_transaction(trans, ret);
3953 goto err;
3954 }
3955 skip_backref:
3956 ret = btrfs_delete_delayed_dir_index(trans, dir, index);
3957 if (ret) {
3958 btrfs_abort_transaction(trans, ret);
3959 goto err;
3960 }
3961
3962 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len, inode,
3963 dir_ino);
3964 if (ret != 0 && ret != -ENOENT) {
3965 btrfs_abort_transaction(trans, ret);
3966 goto err;
3967 }
3968
3969 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len, dir,
3970 index);
3971 if (ret == -ENOENT)
3972 ret = 0;
3973 else if (ret)
3974 btrfs_abort_transaction(trans, ret);
3975 err:
3976 btrfs_free_path(path);
3977 if (ret)
3978 goto out;
3979
3980 btrfs_i_size_write(dir, dir->vfs_inode.i_size - name_len * 2);
3981 inode_inc_iversion(&inode->vfs_inode);
3982 inode_inc_iversion(&dir->vfs_inode);
3983 inode->vfs_inode.i_ctime = dir->vfs_inode.i_mtime =
3984 dir->vfs_inode.i_ctime = current_time(&inode->vfs_inode);
3985 ret = btrfs_update_inode(trans, root, &dir->vfs_inode);
3986 out:
3987 return ret;
3988 }
3989
3990 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3991 struct btrfs_root *root,
3992 struct btrfs_inode *dir, struct btrfs_inode *inode,
3993 const char *name, int name_len)
3994 {
3995 int ret;
3996 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
3997 if (!ret) {
3998 drop_nlink(&inode->vfs_inode);
3999 ret = btrfs_update_inode(trans, root, &inode->vfs_inode);
4000 }
4001 return ret;
4002 }
4003
4004 /*
4005 * helper to start transaction for unlink and rmdir.
4006 *
4007 * unlink and rmdir are special in btrfs, they do not always free space, so
4008 * if we cannot make our reservations the normal way try and see if there is
4009 * plenty of slack room in the global reserve to migrate, otherwise we cannot
4010 * allow the unlink to occur.
4011 */
4012 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir)
4013 {
4014 struct btrfs_root *root = BTRFS_I(dir)->root;
4015
4016 /*
4017 * 1 for the possible orphan item
4018 * 1 for the dir item
4019 * 1 for the dir index
4020 * 1 for the inode ref
4021 * 1 for the inode
4022 */
4023 return btrfs_start_transaction_fallback_global_rsv(root, 5, 5);
4024 }
4025
4026 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
4027 {
4028 struct btrfs_root *root = BTRFS_I(dir)->root;
4029 struct btrfs_trans_handle *trans;
4030 struct inode *inode = d_inode(dentry);
4031 int ret;
4032
4033 trans = __unlink_start_trans(dir);
4034 if (IS_ERR(trans))
4035 return PTR_ERR(trans);
4036
4037 btrfs_record_unlink_dir(trans, BTRFS_I(dir), BTRFS_I(d_inode(dentry)),
4038 0);
4039
4040 ret = btrfs_unlink_inode(trans, root, BTRFS_I(dir),
4041 BTRFS_I(d_inode(dentry)), dentry->d_name.name,
4042 dentry->d_name.len);
4043 if (ret)
4044 goto out;
4045
4046 if (inode->i_nlink == 0) {
4047 ret = btrfs_orphan_add(trans, BTRFS_I(inode));
4048 if (ret)
4049 goto out;
4050 }
4051
4052 out:
4053 btrfs_end_transaction(trans);
4054 btrfs_btree_balance_dirty(root->fs_info);
4055 return ret;
4056 }
4057
4058 static int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
4059 struct inode *dir, u64 objectid,
4060 const char *name, int name_len)
4061 {
4062 struct btrfs_root *root = BTRFS_I(dir)->root;
4063 struct btrfs_path *path;
4064 struct extent_buffer *leaf;
4065 struct btrfs_dir_item *di;
4066 struct btrfs_key key;
4067 u64 index;
4068 int ret;
4069 u64 dir_ino = btrfs_ino(BTRFS_I(dir));
4070
4071 path = btrfs_alloc_path();
4072 if (!path)
4073 return -ENOMEM;
4074
4075 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
4076 name, name_len, -1);
4077 if (IS_ERR_OR_NULL(di)) {
4078 if (!di)
4079 ret = -ENOENT;
4080 else
4081 ret = PTR_ERR(di);
4082 goto out;
4083 }
4084
4085 leaf = path->nodes[0];
4086 btrfs_dir_item_key_to_cpu(leaf, di, &key);
4087 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
4088 ret = btrfs_delete_one_dir_name(trans, root, path, di);
4089 if (ret) {
4090 btrfs_abort_transaction(trans, ret);
4091 goto out;
4092 }
4093 btrfs_release_path(path);
4094
4095 ret = btrfs_del_root_ref(trans, objectid, root->root_key.objectid,
4096 dir_ino, &index, name, name_len);
4097 if (ret < 0) {
4098 if (ret != -ENOENT) {
4099 btrfs_abort_transaction(trans, ret);
4100 goto out;
4101 }
4102 di = btrfs_search_dir_index_item(root, path, dir_ino,
4103 name, name_len);
4104 if (IS_ERR_OR_NULL(di)) {
4105 if (!di)
4106 ret = -ENOENT;
4107 else
4108 ret = PTR_ERR(di);
4109 btrfs_abort_transaction(trans, ret);
4110 goto out;
4111 }
4112
4113 leaf = path->nodes[0];
4114 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
4115 index = key.offset;
4116 }
4117 btrfs_release_path(path);
4118
4119 ret = btrfs_delete_delayed_dir_index(trans, BTRFS_I(dir), index);
4120 if (ret) {
4121 btrfs_abort_transaction(trans, ret);
4122 goto out;
4123 }
4124
4125 btrfs_i_size_write(BTRFS_I(dir), dir->i_size - name_len * 2);
4126 inode_inc_iversion(dir);
4127 dir->i_mtime = dir->i_ctime = current_time(dir);
4128 ret = btrfs_update_inode_fallback(trans, root, dir);
4129 if (ret)
4130 btrfs_abort_transaction(trans, ret);
4131 out:
4132 btrfs_free_path(path);
4133 return ret;
4134 }
4135
4136 /*
4137 * Helper to check if the subvolume references other subvolumes or if it's
4138 * default.
4139 */
4140 static noinline int may_destroy_subvol(struct btrfs_root *root)
4141 {
4142 struct btrfs_fs_info *fs_info = root->fs_info;
4143 struct btrfs_path *path;
4144 struct btrfs_dir_item *di;
4145 struct btrfs_key key;
4146 u64 dir_id;
4147 int ret;
4148
4149 path = btrfs_alloc_path();
4150 if (!path)
4151 return -ENOMEM;
4152
4153 /* Make sure this root isn't set as the default subvol */
4154 dir_id = btrfs_super_root_dir(fs_info->super_copy);
4155 di = btrfs_lookup_dir_item(NULL, fs_info->tree_root, path,
4156 dir_id, "default", 7, 0);
4157 if (di && !IS_ERR(di)) {
4158 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
4159 if (key.objectid == root->root_key.objectid) {
4160 ret = -EPERM;
4161 btrfs_err(fs_info,
4162 "deleting default subvolume %llu is not allowed",
4163 key.objectid);
4164 goto out;
4165 }
4166 btrfs_release_path(path);
4167 }
4168
4169 key.objectid = root->root_key.objectid;
4170 key.type = BTRFS_ROOT_REF_KEY;
4171 key.offset = (u64)-1;
4172
4173 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
4174 if (ret < 0)
4175 goto out;
4176 BUG_ON(ret == 0);
4177
4178 ret = 0;
4179 if (path->slots[0] > 0) {
4180 path->slots[0]--;
4181 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
4182 if (key.objectid == root->root_key.objectid &&
4183 key.type == BTRFS_ROOT_REF_KEY)
4184 ret = -ENOTEMPTY;
4185 }
4186 out:
4187 btrfs_free_path(path);
4188 return ret;
4189 }
4190
4191 /* Delete all dentries for inodes belonging to the root */
4192 static void btrfs_prune_dentries(struct btrfs_root *root)
4193 {
4194 struct btrfs_fs_info *fs_info = root->fs_info;
4195 struct rb_node *node;
4196 struct rb_node *prev;
4197 struct btrfs_inode *entry;
4198 struct inode *inode;
4199 u64 objectid = 0;
4200
4201 if (!test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
4202 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
4203
4204 spin_lock(&root->inode_lock);
4205 again:
4206 node = root->inode_tree.rb_node;
4207 prev = NULL;
4208 while (node) {
4209 prev = node;
4210 entry = rb_entry(node, struct btrfs_inode, rb_node);
4211
4212 if (objectid < btrfs_ino(entry))
4213 node = node->rb_left;
4214 else if (objectid > btrfs_ino(entry))
4215 node = node->rb_right;
4216 else
4217 break;
4218 }
4219 if (!node) {
4220 while (prev) {
4221 entry = rb_entry(prev, struct btrfs_inode, rb_node);
4222 if (objectid <= btrfs_ino(entry)) {
4223 node = prev;
4224 break;
4225 }
4226 prev = rb_next(prev);
4227 }
4228 }
4229 while (node) {
4230 entry = rb_entry(node, struct btrfs_inode, rb_node);
4231 objectid = btrfs_ino(entry) + 1;
4232 inode = igrab(&entry->vfs_inode);
4233 if (inode) {
4234 spin_unlock(&root->inode_lock);
4235 if (atomic_read(&inode->i_count) > 1)
4236 d_prune_aliases(inode);
4237 /*
4238 * btrfs_drop_inode will have it removed from the inode
4239 * cache when its usage count hits zero.
4240 */
4241 iput(inode);
4242 cond_resched();
4243 spin_lock(&root->inode_lock);
4244 goto again;
4245 }
4246
4247 if (cond_resched_lock(&root->inode_lock))
4248 goto again;
4249
4250 node = rb_next(node);
4251 }
4252 spin_unlock(&root->inode_lock);
4253 }
4254
4255 int btrfs_delete_subvolume(struct inode *dir, struct dentry *dentry)
4256 {
4257 struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb);
4258 struct btrfs_root *root = BTRFS_I(dir)->root;
4259 struct inode *inode = d_inode(dentry);
4260 struct btrfs_root *dest = BTRFS_I(inode)->root;
4261 struct btrfs_trans_handle *trans;
4262 struct btrfs_block_rsv block_rsv;
4263 u64 root_flags;
4264 int ret;
4265 int err;
4266
4267 /*
4268 * Don't allow to delete a subvolume with send in progress. This is
4269 * inside the inode lock so the error handling that has to drop the bit
4270 * again is not run concurrently.
4271 */
4272 spin_lock(&dest->root_item_lock);
4273 root_flags = btrfs_root_flags(&dest->root_item);
4274 if (dest->send_in_progress == 0) {
4275 btrfs_set_root_flags(&dest->root_item,
4276 root_flags | BTRFS_ROOT_SUBVOL_DEAD);
4277 spin_unlock(&dest->root_item_lock);
4278 } else {
4279 spin_unlock(&dest->root_item_lock);
4280 btrfs_warn(fs_info,
4281 "attempt to delete subvolume %llu during send",
4282 dest->root_key.objectid);
4283 return -EPERM;
4284 }
4285
4286 down_write(&fs_info->subvol_sem);
4287
4288 err = may_destroy_subvol(dest);
4289 if (err)
4290 goto out_up_write;
4291
4292 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
4293 /*
4294 * One for dir inode,
4295 * two for dir entries,
4296 * two for root ref/backref.
4297 */
4298 err = btrfs_subvolume_reserve_metadata(root, &block_rsv, 5, true);
4299 if (err)
4300 goto out_up_write;
4301
4302 trans = btrfs_start_transaction(root, 0);
4303 if (IS_ERR(trans)) {
4304 err = PTR_ERR(trans);
4305 goto out_release;
4306 }
4307 trans->block_rsv = &block_rsv;
4308 trans->bytes_reserved = block_rsv.size;
4309
4310 btrfs_record_snapshot_destroy(trans, BTRFS_I(dir));
4311
4312 ret = btrfs_unlink_subvol(trans, dir, dest->root_key.objectid,
4313 dentry->d_name.name, dentry->d_name.len);
4314 if (ret) {
4315 err = ret;
4316 btrfs_abort_transaction(trans, ret);
4317 goto out_end_trans;
4318 }
4319
4320 btrfs_record_root_in_trans(trans, dest);
4321
4322 memset(&dest->root_item.drop_progress, 0,
4323 sizeof(dest->root_item.drop_progress));
4324 dest->root_item.drop_level = 0;
4325 btrfs_set_root_refs(&dest->root_item, 0);
4326
4327 if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
4328 ret = btrfs_insert_orphan_item(trans,
4329 fs_info->tree_root,
4330 dest->root_key.objectid);
4331 if (ret) {
4332 btrfs_abort_transaction(trans, ret);
4333 err = ret;
4334 goto out_end_trans;
4335 }
4336 }
4337
4338 ret = btrfs_uuid_tree_remove(trans, dest->root_item.uuid,
4339 BTRFS_UUID_KEY_SUBVOL,
4340 dest->root_key.objectid);
4341 if (ret && ret != -ENOENT) {
4342 btrfs_abort_transaction(trans, ret);
4343 err = ret;
4344 goto out_end_trans;
4345 }
4346 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
4347 ret = btrfs_uuid_tree_remove(trans,
4348 dest->root_item.received_uuid,
4349 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4350 dest->root_key.objectid);
4351 if (ret && ret != -ENOENT) {
4352 btrfs_abort_transaction(trans, ret);
4353 err = ret;
4354 goto out_end_trans;
4355 }
4356 }
4357
4358 out_end_trans:
4359 trans->block_rsv = NULL;
4360 trans->bytes_reserved = 0;
4361 ret = btrfs_end_transaction(trans);
4362 if (ret && !err)
4363 err = ret;
4364 inode->i_flags |= S_DEAD;
4365 out_release:
4366 btrfs_subvolume_release_metadata(fs_info, &block_rsv);
4367 out_up_write:
4368 up_write(&fs_info->subvol_sem);
4369 if (err) {
4370 spin_lock(&dest->root_item_lock);
4371 root_flags = btrfs_root_flags(&dest->root_item);
4372 btrfs_set_root_flags(&dest->root_item,
4373 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
4374 spin_unlock(&dest->root_item_lock);
4375 } else {
4376 d_invalidate(dentry);
4377 btrfs_prune_dentries(dest);
4378 ASSERT(dest->send_in_progress == 0);
4379
4380 /* the last ref */
4381 if (dest->ino_cache_inode) {
4382 iput(dest->ino_cache_inode);
4383 dest->ino_cache_inode = NULL;
4384 }
4385 }
4386
4387 return err;
4388 }
4389
4390 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
4391 {
4392 struct inode *inode = d_inode(dentry);
4393 int err = 0;
4394 struct btrfs_root *root = BTRFS_I(dir)->root;
4395 struct btrfs_trans_handle *trans;
4396 u64 last_unlink_trans;
4397
4398 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
4399 return -ENOTEMPTY;
4400 if (btrfs_ino(BTRFS_I(inode)) == BTRFS_FIRST_FREE_OBJECTID)
4401 return btrfs_delete_subvolume(dir, dentry);
4402
4403 trans = __unlink_start_trans(dir);
4404 if (IS_ERR(trans))
4405 return PTR_ERR(trans);
4406
4407 if (unlikely(btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
4408 err = btrfs_unlink_subvol(trans, dir,
4409 BTRFS_I(inode)->location.objectid,
4410 dentry->d_name.name,
4411 dentry->d_name.len);
4412 goto out;
4413 }
4414
4415 err = btrfs_orphan_add(trans, BTRFS_I(inode));
4416 if (err)
4417 goto out;
4418
4419 last_unlink_trans = BTRFS_I(inode)->last_unlink_trans;
4420
4421 /* now the directory is empty */
4422 err = btrfs_unlink_inode(trans, root, BTRFS_I(dir),
4423 BTRFS_I(d_inode(dentry)), dentry->d_name.name,
4424 dentry->d_name.len);
4425 if (!err) {
4426 btrfs_i_size_write(BTRFS_I(inode), 0);
4427 /*
4428 * Propagate the last_unlink_trans value of the deleted dir to
4429 * its parent directory. This is to prevent an unrecoverable
4430 * log tree in the case we do something like this:
4431 * 1) create dir foo
4432 * 2) create snapshot under dir foo
4433 * 3) delete the snapshot
4434 * 4) rmdir foo
4435 * 5) mkdir foo
4436 * 6) fsync foo or some file inside foo
4437 */
4438 if (last_unlink_trans >= trans->transid)
4439 BTRFS_I(dir)->last_unlink_trans = last_unlink_trans;
4440 }
4441 out:
4442 btrfs_end_transaction(trans);
4443 btrfs_btree_balance_dirty(root->fs_info);
4444
4445 return err;
4446 }
4447
4448 static int truncate_space_check(struct btrfs_trans_handle *trans,
4449 struct btrfs_root *root,
4450 u64 bytes_deleted)
4451 {
4452 struct btrfs_fs_info *fs_info = root->fs_info;
4453 int ret;
4454
4455 /*
4456 * This is only used to apply pressure to the enospc system, we don't
4457 * intend to use this reservation at all.
4458 */
4459 bytes_deleted = btrfs_csum_bytes_to_leaves(fs_info, bytes_deleted);
4460 bytes_deleted *= fs_info->nodesize;
4461 ret = btrfs_block_rsv_add(root, &fs_info->trans_block_rsv,
4462 bytes_deleted, BTRFS_RESERVE_NO_FLUSH);
4463 if (!ret) {
4464 trace_btrfs_space_reservation(fs_info, "transaction",
4465 trans->transid,
4466 bytes_deleted, 1);
4467 trans->bytes_reserved += bytes_deleted;
4468 }
4469 return ret;
4470
4471 }
4472
4473 /*
4474 * Return this if we need to call truncate_block for the last bit of the
4475 * truncate.
4476 */
4477 #define NEED_TRUNCATE_BLOCK 1
4478
4479 /*
4480 * this can truncate away extent items, csum items and directory items.
4481 * It starts at a high offset and removes keys until it can't find
4482 * any higher than new_size
4483 *
4484 * csum items that cross the new i_size are truncated to the new size
4485 * as well.
4486 *
4487 * min_type is the minimum key type to truncate down to. If set to 0, this
4488 * will kill all the items on this inode, including the INODE_ITEM_KEY.
4489 */
4490 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
4491 struct btrfs_root *root,
4492 struct inode *inode,
4493 u64 new_size, u32 min_type)
4494 {
4495 struct btrfs_fs_info *fs_info = root->fs_info;
4496 struct btrfs_path *path;
4497 struct extent_buffer *leaf;
4498 struct btrfs_file_extent_item *fi;
4499 struct btrfs_key key;
4500 struct btrfs_key found_key;
4501 u64 extent_start = 0;
4502 u64 extent_num_bytes = 0;
4503 u64 extent_offset = 0;
4504 u64 item_end = 0;
4505 u64 last_size = new_size;
4506 u32 found_type = (u8)-1;
4507 int found_extent;
4508 int del_item;
4509 int pending_del_nr = 0;
4510 int pending_del_slot = 0;
4511 int extent_type = -1;
4512 int ret;
4513 u64 ino = btrfs_ino(BTRFS_I(inode));
4514 u64 bytes_deleted = 0;
4515 bool be_nice = false;
4516 bool should_throttle = false;
4517 bool should_end = false;
4518
4519 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
4520
4521 /*
4522 * for non-free space inodes and ref cows, we want to back off from
4523 * time to time
4524 */
4525 if (!btrfs_is_free_space_inode(BTRFS_I(inode)) &&
4526 test_bit(BTRFS_ROOT_REF_COWS, &root->state))
4527 be_nice = true;
4528
4529 path = btrfs_alloc_path();
4530 if (!path)
4531 return -ENOMEM;
4532 path->reada = READA_BACK;
4533
4534 /*
4535 * We want to drop from the next block forward in case this new size is
4536 * not block aligned since we will be keeping the last block of the
4537 * extent just the way it is.
4538 */
4539 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
4540 root == fs_info->tree_root)
4541 btrfs_drop_extent_cache(BTRFS_I(inode), ALIGN(new_size,
4542 fs_info->sectorsize),
4543 (u64)-1, 0);
4544
4545 /*
4546 * This function is also used to drop the items in the log tree before
4547 * we relog the inode, so if root != BTRFS_I(inode)->root, it means
4548 * it is used to drop the loged items. So we shouldn't kill the delayed
4549 * items.
4550 */
4551 if (min_type == 0 && root == BTRFS_I(inode)->root)
4552 btrfs_kill_delayed_inode_items(BTRFS_I(inode));
4553
4554 key.objectid = ino;
4555 key.offset = (u64)-1;
4556 key.type = (u8)-1;
4557
4558 search_again:
4559 /*
4560 * with a 16K leaf size and 128MB extents, you can actually queue
4561 * up a huge file in a single leaf. Most of the time that
4562 * bytes_deleted is > 0, it will be huge by the time we get here
4563 */
4564 if (be_nice && bytes_deleted > SZ_32M &&
4565 btrfs_should_end_transaction(trans)) {
4566 ret = -EAGAIN;
4567 goto out;
4568 }
4569
4570 path->leave_spinning = 1;
4571 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
4572 if (ret < 0)
4573 goto out;
4574
4575 if (ret > 0) {
4576 ret = 0;
4577 /* there are no items in the tree for us to truncate, we're
4578 * done
4579 */
4580 if (path->slots[0] == 0)
4581 goto out;
4582 path->slots[0]--;
4583 }
4584
4585 while (1) {
4586 fi = NULL;
4587 leaf = path->nodes[0];
4588 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4589 found_type = found_key.type;
4590
4591 if (found_key.objectid != ino)
4592 break;
4593
4594 if (found_type < min_type)
4595 break;
4596
4597 item_end = found_key.offset;
4598 if (found_type == BTRFS_EXTENT_DATA_KEY) {
4599 fi = btrfs_item_ptr(leaf, path->slots[0],
4600 struct btrfs_file_extent_item);
4601 extent_type = btrfs_file_extent_type(leaf, fi);
4602 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
4603 item_end +=
4604 btrfs_file_extent_num_bytes(leaf, fi);
4605
4606 trace_btrfs_truncate_show_fi_regular(
4607 BTRFS_I(inode), leaf, fi,
4608 found_key.offset);
4609 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
4610 item_end += btrfs_file_extent_ram_bytes(leaf,
4611 fi);
4612
4613 trace_btrfs_truncate_show_fi_inline(
4614 BTRFS_I(inode), leaf, fi, path->slots[0],
4615 found_key.offset);
4616 }
4617 item_end--;
4618 }
4619 if (found_type > min_type) {
4620 del_item = 1;
4621 } else {
4622 if (item_end < new_size)
4623 break;
4624 if (found_key.offset >= new_size)
4625 del_item = 1;
4626 else
4627 del_item = 0;
4628 }
4629 found_extent = 0;
4630 /* FIXME, shrink the extent if the ref count is only 1 */
4631 if (found_type != BTRFS_EXTENT_DATA_KEY)
4632 goto delete;
4633
4634 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
4635 u64 num_dec;
4636 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
4637 if (!del_item) {
4638 u64 orig_num_bytes =
4639 btrfs_file_extent_num_bytes(leaf, fi);
4640 extent_num_bytes = ALIGN(new_size -
4641 found_key.offset,
4642 fs_info->sectorsize);
4643 btrfs_set_file_extent_num_bytes(leaf, fi,
4644 extent_num_bytes);
4645 num_dec = (orig_num_bytes -
4646 extent_num_bytes);
4647 if (test_bit(BTRFS_ROOT_REF_COWS,
4648 &root->state) &&
4649 extent_start != 0)
4650 inode_sub_bytes(inode, num_dec);
4651 btrfs_mark_buffer_dirty(leaf);
4652 } else {
4653 extent_num_bytes =
4654 btrfs_file_extent_disk_num_bytes(leaf,
4655 fi);
4656 extent_offset = found_key.offset -
4657 btrfs_file_extent_offset(leaf, fi);
4658
4659 /* FIXME blocksize != 4096 */
4660 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
4661 if (extent_start != 0) {
4662 found_extent = 1;
4663 if (test_bit(BTRFS_ROOT_REF_COWS,
4664 &root->state))
4665 inode_sub_bytes(inode, num_dec);
4666 }
4667 }
4668 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
4669 /*
4670 * we can't truncate inline items that have had
4671 * special encodings
4672 */
4673 if (!del_item &&
4674 btrfs_file_extent_encryption(leaf, fi) == 0 &&
4675 btrfs_file_extent_other_encoding(leaf, fi) == 0 &&
4676 btrfs_file_extent_compression(leaf, fi) == 0) {
4677 u32 size = (u32)(new_size - found_key.offset);
4678
4679 btrfs_set_file_extent_ram_bytes(leaf, fi, size);
4680 size = btrfs_file_extent_calc_inline_size(size);
4681 btrfs_truncate_item(root->fs_info, path, size, 1);
4682 } else if (!del_item) {
4683 /*
4684 * We have to bail so the last_size is set to
4685 * just before this extent.
4686 */
4687 ret = NEED_TRUNCATE_BLOCK;
4688 break;
4689 }
4690
4691 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state))
4692 inode_sub_bytes(inode, item_end + 1 - new_size);
4693 }
4694 delete:
4695 if (del_item)
4696 last_size = found_key.offset;
4697 else
4698 last_size = new_size;
4699 if (del_item) {
4700 if (!pending_del_nr) {
4701 /* no pending yet, add ourselves */
4702 pending_del_slot = path->slots[0];
4703 pending_del_nr = 1;
4704 } else if (pending_del_nr &&
4705 path->slots[0] + 1 == pending_del_slot) {
4706 /* hop on the pending chunk */
4707 pending_del_nr++;
4708 pending_del_slot = path->slots[0];
4709 } else {
4710 BUG();
4711 }
4712 } else {
4713 break;
4714 }
4715 should_throttle = false;
4716
4717 if (found_extent &&
4718 (test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
4719 root == fs_info->tree_root)) {
4720 btrfs_set_path_blocking(path);
4721 bytes_deleted += extent_num_bytes;
4722 ret = btrfs_free_extent(trans, root, extent_start,
4723 extent_num_bytes, 0,
4724 btrfs_header_owner(leaf),
4725 ino, extent_offset);
4726 if (ret) {
4727 btrfs_abort_transaction(trans, ret);
4728 break;
4729 }
4730 if (btrfs_should_throttle_delayed_refs(trans, fs_info))
4731 btrfs_async_run_delayed_refs(fs_info,
4732 trans->delayed_ref_updates * 2,
4733 trans->transid, 0);
4734 if (be_nice) {
4735 if (truncate_space_check(trans, root,
4736 extent_num_bytes)) {
4737 should_end = true;
4738 }
4739 if (btrfs_should_throttle_delayed_refs(trans,
4740 fs_info))
4741 should_throttle = true;
4742 }
4743 }
4744
4745 if (found_type == BTRFS_INODE_ITEM_KEY)
4746 break;
4747
4748 if (path->slots[0] == 0 ||
4749 path->slots[0] != pending_del_slot ||
4750 should_throttle || should_end) {
4751 if (pending_del_nr) {
4752 ret = btrfs_del_items(trans, root, path,
4753 pending_del_slot,
4754 pending_del_nr);
4755 if (ret) {
4756 btrfs_abort_transaction(trans, ret);
4757 break;
4758 }
4759 pending_del_nr = 0;
4760 }
4761 btrfs_release_path(path);
4762 if (should_throttle) {
4763 unsigned long updates = trans->delayed_ref_updates;
4764 if (updates) {
4765 trans->delayed_ref_updates = 0;
4766 ret = btrfs_run_delayed_refs(trans,
4767 updates * 2);
4768 if (ret)
4769 break;
4770 }
4771 }
4772 /*
4773 * if we failed to refill our space rsv, bail out
4774 * and let the transaction restart
4775 */
4776 if (should_end) {
4777 ret = -EAGAIN;
4778 break;
4779 }
4780 goto search_again;
4781 } else {
4782 path->slots[0]--;
4783 }
4784 }
4785 out:
4786 if (ret >= 0 && pending_del_nr) {
4787 int err;
4788
4789 err = btrfs_del_items(trans, root, path, pending_del_slot,
4790 pending_del_nr);
4791 if (err) {
4792 btrfs_abort_transaction(trans, err);
4793 ret = err;
4794 }
4795 }
4796 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4797 ASSERT(last_size >= new_size);
4798 if (!ret && last_size > new_size)
4799 last_size = new_size;
4800 btrfs_ordered_update_i_size(inode, last_size, NULL);
4801 }
4802
4803 btrfs_free_path(path);
4804
4805 if (be_nice && bytes_deleted > SZ_32M && (ret >= 0 || ret == -EAGAIN)) {
4806 unsigned long updates = trans->delayed_ref_updates;
4807 int err;
4808
4809 if (updates) {
4810 trans->delayed_ref_updates = 0;
4811 err = btrfs_run_delayed_refs(trans, updates * 2);
4812 if (err)
4813 ret = err;
4814 }
4815 }
4816 return ret;
4817 }
4818
4819 /*
4820 * btrfs_truncate_block - read, zero a chunk and write a block
4821 * @inode - inode that we're zeroing
4822 * @from - the offset to start zeroing
4823 * @len - the length to zero, 0 to zero the entire range respective to the
4824 * offset
4825 * @front - zero up to the offset instead of from the offset on
4826 *
4827 * This will find the block for the "from" offset and cow the block and zero the
4828 * part we want to zero. This is used with truncate and hole punching.
4829 */
4830 int btrfs_truncate_block(struct inode *inode, loff_t from, loff_t len,
4831 int front)
4832 {
4833 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4834 struct address_space *mapping = inode->i_mapping;
4835 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4836 struct btrfs_ordered_extent *ordered;
4837 struct extent_state *cached_state = NULL;
4838 struct extent_changeset *data_reserved = NULL;
4839 char *kaddr;
4840 u32 blocksize = fs_info->sectorsize;
4841 pgoff_t index = from >> PAGE_SHIFT;
4842 unsigned offset = from & (blocksize - 1);
4843 struct page *page;
4844 gfp_t mask = btrfs_alloc_write_mask(mapping);
4845 int ret = 0;
4846 u64 block_start;
4847 u64 block_end;
4848
4849 if (IS_ALIGNED(offset, blocksize) &&
4850 (!len || IS_ALIGNED(len, blocksize)))
4851 goto out;
4852
4853 block_start = round_down(from, blocksize);
4854 block_end = block_start + blocksize - 1;
4855
4856 ret = btrfs_delalloc_reserve_space(inode, &data_reserved,
4857 block_start, blocksize);
4858 if (ret)
4859 goto out;
4860
4861 again:
4862 page = find_or_create_page(mapping, index, mask);
4863 if (!page) {
4864 btrfs_delalloc_release_space(inode, data_reserved,
4865 block_start, blocksize, true);
4866 btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, true);
4867 ret = -ENOMEM;
4868 goto out;
4869 }
4870
4871 if (!PageUptodate(page)) {
4872 ret = btrfs_readpage(NULL, page);
4873 lock_page(page);
4874 if (page->mapping != mapping) {
4875 unlock_page(page);
4876 put_page(page);
4877 goto again;
4878 }
4879 if (!PageUptodate(page)) {
4880 ret = -EIO;
4881 goto out_unlock;
4882 }
4883 }
4884 wait_on_page_writeback(page);
4885
4886 lock_extent_bits(io_tree, block_start, block_end, &cached_state);
4887 set_page_extent_mapped(page);
4888
4889 ordered = btrfs_lookup_ordered_extent(inode, block_start);
4890 if (ordered) {
4891 unlock_extent_cached(io_tree, block_start, block_end,
4892 &cached_state);
4893 unlock_page(page);
4894 put_page(page);
4895 btrfs_start_ordered_extent(inode, ordered, 1);
4896 btrfs_put_ordered_extent(ordered);
4897 goto again;
4898 }
4899
4900 clear_extent_bit(&BTRFS_I(inode)->io_tree, block_start, block_end,
4901 EXTENT_DIRTY | EXTENT_DELALLOC |
4902 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
4903 0, 0, &cached_state);
4904
4905 ret = btrfs_set_extent_delalloc(inode, block_start, block_end, 0,
4906 &cached_state, 0);
4907 if (ret) {
4908 unlock_extent_cached(io_tree, block_start, block_end,
4909 &cached_state);
4910 goto out_unlock;
4911 }
4912
4913 if (offset != blocksize) {
4914 if (!len)
4915 len = blocksize - offset;
4916 kaddr = kmap(page);
4917 if (front)
4918 memset(kaddr + (block_start - page_offset(page)),
4919 0, offset);
4920 else
4921 memset(kaddr + (block_start - page_offset(page)) + offset,
4922 0, len);
4923 flush_dcache_page(page);
4924 kunmap(page);
4925 }
4926 ClearPageChecked(page);
4927 set_page_dirty(page);
4928 unlock_extent_cached(io_tree, block_start, block_end, &cached_state);
4929
4930 out_unlock:
4931 if (ret)
4932 btrfs_delalloc_release_space(inode, data_reserved, block_start,
4933 blocksize, true);
4934 btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, (ret != 0));
4935 unlock_page(page);
4936 put_page(page);
4937 out:
4938 extent_changeset_free(data_reserved);
4939 return ret;
4940 }
4941
4942 static int maybe_insert_hole(struct btrfs_root *root, struct inode *inode,
4943 u64 offset, u64 len)
4944 {
4945 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4946 struct btrfs_trans_handle *trans;
4947 int ret;
4948
4949 /*
4950 * Still need to make sure the inode looks like it's been updated so
4951 * that any holes get logged if we fsync.
4952 */
4953 if (btrfs_fs_incompat(fs_info, NO_HOLES)) {
4954 BTRFS_I(inode)->last_trans = fs_info->generation;
4955 BTRFS_I(inode)->last_sub_trans = root->log_transid;
4956 BTRFS_I(inode)->last_log_commit = root->last_log_commit;
4957 return 0;
4958 }
4959
4960 /*
4961 * 1 - for the one we're dropping
4962 * 1 - for the one we're adding
4963 * 1 - for updating the inode.
4964 */
4965 trans = btrfs_start_transaction(root, 3);
4966 if (IS_ERR(trans))
4967 return PTR_ERR(trans);
4968
4969 ret = btrfs_drop_extents(trans, root, inode, offset, offset + len, 1);
4970 if (ret) {
4971 btrfs_abort_transaction(trans, ret);
4972 btrfs_end_transaction(trans);
4973 return ret;
4974 }
4975
4976 ret = btrfs_insert_file_extent(trans, root, btrfs_ino(BTRFS_I(inode)),
4977 offset, 0, 0, len, 0, len, 0, 0, 0);
4978 if (ret)
4979 btrfs_abort_transaction(trans, ret);
4980 else
4981 btrfs_update_inode(trans, root, inode);
4982 btrfs_end_transaction(trans);
4983 return ret;
4984 }
4985
4986 /*
4987 * This function puts in dummy file extents for the area we're creating a hole
4988 * for. So if we are truncating this file to a larger size we need to insert
4989 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
4990 * the range between oldsize and size
4991 */
4992 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
4993 {
4994 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4995 struct btrfs_root *root = BTRFS_I(inode)->root;
4996 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4997 struct extent_map *em = NULL;
4998 struct extent_state *cached_state = NULL;
4999 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
5000 u64 hole_start = ALIGN(oldsize, fs_info->sectorsize);
5001 u64 block_end = ALIGN(size, fs_info->sectorsize);
5002 u64 last_byte;
5003 u64 cur_offset;
5004 u64 hole_size;
5005 int err = 0;
5006
5007 /*
5008 * If our size started in the middle of a block we need to zero out the
5009 * rest of the block before we expand the i_size, otherwise we could
5010 * expose stale data.
5011 */
5012 err = btrfs_truncate_block(inode, oldsize, 0, 0);
5013 if (err)
5014 return err;
5015
5016 if (size <= hole_start)
5017 return 0;
5018
5019 while (1) {
5020 struct btrfs_ordered_extent *ordered;
5021
5022 lock_extent_bits(io_tree, hole_start, block_end - 1,
5023 &cached_state);
5024 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), hole_start,
5025 block_end - hole_start);
5026 if (!ordered)
5027 break;
5028 unlock_extent_cached(io_tree, hole_start, block_end - 1,
5029 &cached_state);
5030 btrfs_start_ordered_extent(inode, ordered, 1);
5031 btrfs_put_ordered_extent(ordered);
5032 }
5033
5034 cur_offset = hole_start;
5035 while (1) {
5036 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, cur_offset,
5037 block_end - cur_offset, 0);
5038 if (IS_ERR(em)) {
5039 err = PTR_ERR(em);
5040 em = NULL;
5041 break;
5042 }
5043 last_byte = min(extent_map_end(em), block_end);
5044 last_byte = ALIGN(last_byte, fs_info->sectorsize);
5045 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
5046 struct extent_map *hole_em;
5047 hole_size = last_byte - cur_offset;
5048
5049 err = maybe_insert_hole(root, inode, cur_offset,
5050 hole_size);
5051 if (err)
5052 break;
5053 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset,
5054 cur_offset + hole_size - 1, 0);
5055 hole_em = alloc_extent_map();
5056 if (!hole_em) {
5057 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
5058 &BTRFS_I(inode)->runtime_flags);
5059 goto next;
5060 }
5061 hole_em->start = cur_offset;
5062 hole_em->len = hole_size;
5063 hole_em->orig_start = cur_offset;
5064
5065 hole_em->block_start = EXTENT_MAP_HOLE;
5066 hole_em->block_len = 0;
5067 hole_em->orig_block_len = 0;
5068 hole_em->ram_bytes = hole_size;
5069 hole_em->bdev = fs_info->fs_devices->latest_bdev;
5070 hole_em->compress_type = BTRFS_COMPRESS_NONE;
5071 hole_em->generation = fs_info->generation;
5072
5073 while (1) {
5074 write_lock(&em_tree->lock);
5075 err = add_extent_mapping(em_tree, hole_em, 1);
5076 write_unlock(&em_tree->lock);
5077 if (err != -EEXIST)
5078 break;
5079 btrfs_drop_extent_cache(BTRFS_I(inode),
5080 cur_offset,
5081 cur_offset +
5082 hole_size - 1, 0);
5083 }
5084 free_extent_map(hole_em);
5085 }
5086 next:
5087 free_extent_map(em);
5088 em = NULL;
5089 cur_offset = last_byte;
5090 if (cur_offset >= block_end)
5091 break;
5092 }
5093 free_extent_map(em);
5094 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state);
5095 return err;
5096 }
5097
5098 static int btrfs_setsize(struct inode *inode, struct iattr *attr)
5099 {
5100 struct btrfs_root *root = BTRFS_I(inode)->root;
5101 struct btrfs_trans_handle *trans;
5102 loff_t oldsize = i_size_read(inode);
5103 loff_t newsize = attr->ia_size;
5104 int mask = attr->ia_valid;
5105 int ret;
5106
5107 /*
5108 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a
5109 * special case where we need to update the times despite not having
5110 * these flags set. For all other operations the VFS set these flags
5111 * explicitly if it wants a timestamp update.
5112 */
5113 if (newsize != oldsize) {
5114 inode_inc_iversion(inode);
5115 if (!(mask & (ATTR_CTIME | ATTR_MTIME)))
5116 inode->i_ctime = inode->i_mtime =
5117 current_time(inode);
5118 }
5119
5120 if (newsize > oldsize) {
5121 /*
5122 * Don't do an expanding truncate while snapshotting is ongoing.
5123 * This is to ensure the snapshot captures a fully consistent
5124 * state of this file - if the snapshot captures this expanding
5125 * truncation, it must capture all writes that happened before
5126 * this truncation.
5127 */
5128 btrfs_wait_for_snapshot_creation(root);
5129 ret = btrfs_cont_expand(inode, oldsize, newsize);
5130 if (ret) {
5131 btrfs_end_write_no_snapshotting(root);
5132 return ret;
5133 }
5134
5135 trans = btrfs_start_transaction(root, 1);
5136 if (IS_ERR(trans)) {
5137 btrfs_end_write_no_snapshotting(root);
5138 return PTR_ERR(trans);
5139 }
5140
5141 i_size_write(inode, newsize);
5142 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL);
5143 pagecache_isize_extended(inode, oldsize, newsize);
5144 ret = btrfs_update_inode(trans, root, inode);
5145 btrfs_end_write_no_snapshotting(root);
5146 btrfs_end_transaction(trans);
5147 } else {
5148
5149 /*
5150 * We're truncating a file that used to have good data down to
5151 * zero. Make sure it gets into the ordered flush list so that
5152 * any new writes get down to disk quickly.
5153 */
5154 if (newsize == 0)
5155 set_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
5156 &BTRFS_I(inode)->runtime_flags);
5157
5158 truncate_setsize(inode, newsize);
5159
5160 /* Disable nonlocked read DIO to avoid the end less truncate */
5161 btrfs_inode_block_unlocked_dio(BTRFS_I(inode));
5162 inode_dio_wait(inode);
5163 btrfs_inode_resume_unlocked_dio(BTRFS_I(inode));
5164
5165 ret = btrfs_truncate(inode, newsize == oldsize);
5166 if (ret && inode->i_nlink) {
5167 int err;
5168
5169 /*
5170 * Truncate failed, so fix up the in-memory size. We
5171 * adjusted disk_i_size down as we removed extents, so
5172 * wait for disk_i_size to be stable and then update the
5173 * in-memory size to match.
5174 */
5175 err = btrfs_wait_ordered_range(inode, 0, (u64)-1);
5176 if (err)
5177 return err;
5178 i_size_write(inode, BTRFS_I(inode)->disk_i_size);
5179 }
5180 }
5181
5182 return ret;
5183 }
5184
5185 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
5186 {
5187 struct inode *inode = d_inode(dentry);
5188 struct btrfs_root *root = BTRFS_I(inode)->root;
5189 int err;
5190
5191 if (btrfs_root_readonly(root))
5192 return -EROFS;
5193
5194 err = setattr_prepare(dentry, attr);
5195 if (err)
5196 return err;
5197
5198 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
5199 err = btrfs_setsize(inode, attr);
5200 if (err)
5201 return err;
5202 }
5203
5204 if (attr->ia_valid) {
5205 setattr_copy(inode, attr);
5206 inode_inc_iversion(inode);
5207 err = btrfs_dirty_inode(inode);
5208
5209 if (!err && attr->ia_valid & ATTR_MODE)
5210 err = posix_acl_chmod(inode, inode->i_mode);
5211 }
5212
5213 return err;
5214 }
5215
5216 /*
5217 * While truncating the inode pages during eviction, we get the VFS calling
5218 * btrfs_invalidatepage() against each page of the inode. This is slow because
5219 * the calls to btrfs_invalidatepage() result in a huge amount of calls to
5220 * lock_extent_bits() and clear_extent_bit(), which keep merging and splitting
5221 * extent_state structures over and over, wasting lots of time.
5222 *
5223 * Therefore if the inode is being evicted, let btrfs_invalidatepage() skip all
5224 * those expensive operations on a per page basis and do only the ordered io
5225 * finishing, while we release here the extent_map and extent_state structures,
5226 * without the excessive merging and splitting.
5227 */
5228 static void evict_inode_truncate_pages(struct inode *inode)
5229 {
5230 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
5231 struct extent_map_tree *map_tree = &BTRFS_I(inode)->extent_tree;
5232 struct rb_node *node;
5233
5234 ASSERT(inode->i_state & I_FREEING);
5235 truncate_inode_pages_final(&inode->i_data);
5236
5237 write_lock(&map_tree->lock);
5238 while (!RB_EMPTY_ROOT(&map_tree->map)) {
5239 struct extent_map *em;
5240
5241 node = rb_first(&map_tree->map);
5242 em = rb_entry(node, struct extent_map, rb_node);
5243 clear_bit(EXTENT_FLAG_PINNED, &em->flags);
5244 clear_bit(EXTENT_FLAG_LOGGING, &em->flags);
5245 remove_extent_mapping(map_tree, em);
5246 free_extent_map(em);
5247 if (need_resched()) {
5248 write_unlock(&map_tree->lock);
5249 cond_resched();
5250 write_lock(&map_tree->lock);
5251 }
5252 }
5253 write_unlock(&map_tree->lock);
5254
5255 /*
5256 * Keep looping until we have no more ranges in the io tree.
5257 * We can have ongoing bios started by readpages (called from readahead)
5258 * that have their endio callback (extent_io.c:end_bio_extent_readpage)
5259 * still in progress (unlocked the pages in the bio but did not yet
5260 * unlocked the ranges in the io tree). Therefore this means some
5261 * ranges can still be locked and eviction started because before
5262 * submitting those bios, which are executed by a separate task (work
5263 * queue kthread), inode references (inode->i_count) were not taken
5264 * (which would be dropped in the end io callback of each bio).
5265 * Therefore here we effectively end up waiting for those bios and
5266 * anyone else holding locked ranges without having bumped the inode's
5267 * reference count - if we don't do it, when they access the inode's
5268 * io_tree to unlock a range it may be too late, leading to an
5269 * use-after-free issue.
5270 */
5271 spin_lock(&io_tree->lock);
5272 while (!RB_EMPTY_ROOT(&io_tree->state)) {
5273 struct extent_state *state;
5274 struct extent_state *cached_state = NULL;
5275 u64 start;
5276 u64 end;
5277
5278 node = rb_first(&io_tree->state);
5279 state = rb_entry(node, struct extent_state, rb_node);
5280 start = state->start;
5281 end = state->end;
5282 spin_unlock(&io_tree->lock);
5283
5284 lock_extent_bits(io_tree, start, end, &cached_state);
5285
5286 /*
5287 * If still has DELALLOC flag, the extent didn't reach disk,
5288 * and its reserved space won't be freed by delayed_ref.
5289 * So we need to free its reserved space here.
5290 * (Refer to comment in btrfs_invalidatepage, case 2)
5291 *
5292 * Note, end is the bytenr of last byte, so we need + 1 here.
5293 */
5294 if (state->state & EXTENT_DELALLOC)
5295 btrfs_qgroup_free_data(inode, NULL, start, end - start + 1);
5296
5297 clear_extent_bit(io_tree, start, end,
5298 EXTENT_LOCKED | EXTENT_DIRTY |
5299 EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |
5300 EXTENT_DEFRAG, 1, 1, &cached_state);
5301
5302 cond_resched();
5303 spin_lock(&io_tree->lock);
5304 }
5305 spin_unlock(&io_tree->lock);
5306 }
5307
5308 static struct btrfs_trans_handle *evict_refill_and_join(struct btrfs_root *root,
5309 struct btrfs_block_rsv *rsv,
5310 u64 min_size)
5311 {
5312 struct btrfs_fs_info *fs_info = root->fs_info;
5313 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
5314 int failures = 0;
5315
5316 for (;;) {
5317 struct btrfs_trans_handle *trans;
5318 int ret;
5319
5320 ret = btrfs_block_rsv_refill(root, rsv, min_size,
5321 BTRFS_RESERVE_FLUSH_LIMIT);
5322
5323 if (ret && ++failures > 2) {
5324 btrfs_warn(fs_info,
5325 "could not allocate space for a delete; will truncate on mount");
5326 return ERR_PTR(-ENOSPC);
5327 }
5328
5329 trans = btrfs_join_transaction(root);
5330 if (IS_ERR(trans) || !ret)
5331 return trans;
5332
5333 /*
5334 * Try to steal from the global reserve if there is space for
5335 * it.
5336 */
5337 if (!btrfs_check_space_for_delayed_refs(trans, fs_info) &&
5338 !btrfs_block_rsv_migrate(global_rsv, rsv, min_size, 0))
5339 return trans;
5340
5341 /* If not, commit and try again. */
5342 ret = btrfs_commit_transaction(trans);
5343 if (ret)
5344 return ERR_PTR(ret);
5345 }
5346 }
5347
5348 void btrfs_evict_inode(struct inode *inode)
5349 {
5350 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5351 struct btrfs_trans_handle *trans;
5352 struct btrfs_root *root = BTRFS_I(inode)->root;
5353 struct btrfs_block_rsv *rsv;
5354 u64 min_size;
5355 int ret;
5356
5357 trace_btrfs_inode_evict(inode);
5358
5359 if (!root) {
5360 clear_inode(inode);
5361 return;
5362 }
5363
5364 min_size = btrfs_calc_trunc_metadata_size(fs_info, 1);
5365
5366 evict_inode_truncate_pages(inode);
5367
5368 if (inode->i_nlink &&
5369 ((btrfs_root_refs(&root->root_item) != 0 &&
5370 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID) ||
5371 btrfs_is_free_space_inode(BTRFS_I(inode))))
5372 goto no_delete;
5373
5374 if (is_bad_inode(inode))
5375 goto no_delete;
5376 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */
5377 if (!special_file(inode->i_mode))
5378 btrfs_wait_ordered_range(inode, 0, (u64)-1);
5379
5380 btrfs_free_io_failure_record(BTRFS_I(inode), 0, (u64)-1);
5381
5382 if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
5383 goto no_delete;
5384
5385 if (inode->i_nlink > 0) {
5386 BUG_ON(btrfs_root_refs(&root->root_item) != 0 &&
5387 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID);
5388 goto no_delete;
5389 }
5390
5391 ret = btrfs_commit_inode_delayed_inode(BTRFS_I(inode));
5392 if (ret)
5393 goto no_delete;
5394
5395 rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP);
5396 if (!rsv)
5397 goto no_delete;
5398 rsv->size = min_size;
5399 rsv->failfast = 1;
5400
5401 btrfs_i_size_write(BTRFS_I(inode), 0);
5402
5403 while (1) {
5404 trans = evict_refill_and_join(root, rsv, min_size);
5405 if (IS_ERR(trans))
5406 goto free_rsv;
5407
5408 trans->block_rsv = rsv;
5409
5410 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
5411 trans->block_rsv = &fs_info->trans_block_rsv;
5412 btrfs_end_transaction(trans);
5413 btrfs_btree_balance_dirty(fs_info);
5414 if (ret && ret != -ENOSPC && ret != -EAGAIN)
5415 goto free_rsv;
5416 else if (!ret)
5417 break;
5418 }
5419
5420 /*
5421 * Errors here aren't a big deal, it just means we leave orphan items in
5422 * the tree. They will be cleaned up on the next mount. If the inode
5423 * number gets reused, cleanup deletes the orphan item without doing
5424 * anything, and unlink reuses the existing orphan item.
5425 *
5426 * If it turns out that we are dropping too many of these, we might want
5427 * to add a mechanism for retrying these after a commit.
5428 */
5429 trans = evict_refill_and_join(root, rsv, min_size);
5430 if (!IS_ERR(trans)) {
5431 trans->block_rsv = rsv;
5432 btrfs_orphan_del(trans, BTRFS_I(inode));
5433 trans->block_rsv = &fs_info->trans_block_rsv;
5434 btrfs_end_transaction(trans);
5435 }
5436
5437 if (!(root == fs_info->tree_root ||
5438 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
5439 btrfs_return_ino(root, btrfs_ino(BTRFS_I(inode)));
5440
5441 free_rsv:
5442 btrfs_free_block_rsv(fs_info, rsv);
5443 no_delete:
5444 /*
5445 * If we didn't successfully delete, the orphan item will still be in
5446 * the tree and we'll retry on the next mount. Again, we might also want
5447 * to retry these periodically in the future.
5448 */
5449 btrfs_remove_delayed_node(BTRFS_I(inode));
5450 clear_inode(inode);
5451 }
5452
5453 /*
5454 * this returns the key found in the dir entry in the location pointer.
5455 * If no dir entries were found, returns -ENOENT.
5456 * If found a corrupted location in dir entry, returns -EUCLEAN.
5457 */
5458 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
5459 struct btrfs_key *location)
5460 {
5461 const char *name = dentry->d_name.name;
5462 int namelen = dentry->d_name.len;
5463 struct btrfs_dir_item *di;
5464 struct btrfs_path *path;
5465 struct btrfs_root *root = BTRFS_I(dir)->root;
5466 int ret = 0;
5467
5468 path = btrfs_alloc_path();
5469 if (!path)
5470 return -ENOMEM;
5471
5472 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(BTRFS_I(dir)),
5473 name, namelen, 0);
5474 if (!di) {
5475 ret = -ENOENT;
5476 goto out;
5477 }
5478 if (IS_ERR(di)) {
5479 ret = PTR_ERR(di);
5480 goto out;
5481 }
5482
5483 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
5484 if (location->type != BTRFS_INODE_ITEM_KEY &&
5485 location->type != BTRFS_ROOT_ITEM_KEY) {
5486 ret = -EUCLEAN;
5487 btrfs_warn(root->fs_info,
5488 "%s gets something invalid in DIR_ITEM (name %s, directory ino %llu, location(%llu %u %llu))",
5489 __func__, name, btrfs_ino(BTRFS_I(dir)),
5490 location->objectid, location->type, location->offset);
5491 }
5492 out:
5493 btrfs_free_path(path);
5494 return ret;
5495 }
5496
5497 /*
5498 * when we hit a tree root in a directory, the btrfs part of the inode
5499 * needs to be changed to reflect the root directory of the tree root. This
5500 * is kind of like crossing a mount point.
5501 */
5502 static int fixup_tree_root_location(struct btrfs_fs_info *fs_info,
5503 struct inode *dir,
5504 struct dentry *dentry,
5505 struct btrfs_key *location,
5506 struct btrfs_root **sub_root)
5507 {
5508 struct btrfs_path *path;
5509 struct btrfs_root *new_root;
5510 struct btrfs_root_ref *ref;
5511 struct extent_buffer *leaf;
5512 struct btrfs_key key;
5513 int ret;
5514 int err = 0;
5515
5516 path = btrfs_alloc_path();
5517 if (!path) {
5518 err = -ENOMEM;
5519 goto out;
5520 }
5521
5522 err = -ENOENT;
5523 key.objectid = BTRFS_I(dir)->root->root_key.objectid;
5524 key.type = BTRFS_ROOT_REF_KEY;
5525 key.offset = location->objectid;
5526
5527 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
5528 if (ret) {
5529 if (ret < 0)
5530 err = ret;
5531 goto out;
5532 }
5533
5534 leaf = path->nodes[0];
5535 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
5536 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(BTRFS_I(dir)) ||
5537 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
5538 goto out;
5539
5540 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
5541 (unsigned long)(ref + 1),
5542 dentry->d_name.len);
5543 if (ret)
5544 goto out;
5545
5546 btrfs_release_path(path);
5547
5548 new_root = btrfs_read_fs_root_no_name(fs_info, location);
5549 if (IS_ERR(new_root)) {
5550 err = PTR_ERR(new_root);
5551 goto out;
5552 }
5553
5554 *sub_root = new_root;
5555 location->objectid = btrfs_root_dirid(&new_root->root_item);
5556 location->type = BTRFS_INODE_ITEM_KEY;
5557 location->offset = 0;
5558 err = 0;
5559 out:
5560 btrfs_free_path(path);
5561 return err;
5562 }
5563
5564 static void inode_tree_add(struct inode *inode)
5565 {
5566 struct btrfs_root *root = BTRFS_I(inode)->root;
5567 struct btrfs_inode *entry;
5568 struct rb_node **p;
5569 struct rb_node *parent;
5570 struct rb_node *new = &BTRFS_I(inode)->rb_node;
5571 u64 ino = btrfs_ino(BTRFS_I(inode));
5572
5573 if (inode_unhashed(inode))
5574 return;
5575 parent = NULL;
5576 spin_lock(&root->inode_lock);
5577 p = &root->inode_tree.rb_node;
5578 while (*p) {
5579 parent = *p;
5580 entry = rb_entry(parent, struct btrfs_inode, rb_node);
5581
5582 if (ino < btrfs_ino(entry))
5583 p = &parent->rb_left;
5584 else if (ino > btrfs_ino(entry))
5585 p = &parent->rb_right;
5586 else {
5587 WARN_ON(!(entry->vfs_inode.i_state &
5588 (I_WILL_FREE | I_FREEING)));
5589 rb_replace_node(parent, new, &root->inode_tree);
5590 RB_CLEAR_NODE(parent);
5591 spin_unlock(&root->inode_lock);
5592 return;
5593 }
5594 }
5595 rb_link_node(new, parent, p);
5596 rb_insert_color(new, &root->inode_tree);
5597 spin_unlock(&root->inode_lock);
5598 }
5599
5600 static void inode_tree_del(struct inode *inode)
5601 {
5602 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5603 struct btrfs_root *root = BTRFS_I(inode)->root;
5604 int empty = 0;
5605
5606 spin_lock(&root->inode_lock);
5607 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
5608 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
5609 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
5610 empty = RB_EMPTY_ROOT(&root->inode_tree);
5611 }
5612 spin_unlock(&root->inode_lock);
5613
5614 if (empty && btrfs_root_refs(&root->root_item) == 0) {
5615 synchronize_srcu(&fs_info->subvol_srcu);
5616 spin_lock(&root->inode_lock);
5617 empty = RB_EMPTY_ROOT(&root->inode_tree);
5618 spin_unlock(&root->inode_lock);
5619 if (empty)
5620 btrfs_add_dead_root(root);
5621 }
5622 }
5623
5624
5625 static int btrfs_init_locked_inode(struct inode *inode, void *p)
5626 {
5627 struct btrfs_iget_args *args = p;
5628 inode->i_ino = args->location->objectid;
5629 memcpy(&BTRFS_I(inode)->location, args->location,
5630 sizeof(*args->location));
5631 BTRFS_I(inode)->root = args->root;
5632 return 0;
5633 }
5634
5635 static int btrfs_find_actor(struct inode *inode, void *opaque)
5636 {
5637 struct btrfs_iget_args *args = opaque;
5638 return args->location->objectid == BTRFS_I(inode)->location.objectid &&
5639 args->root == BTRFS_I(inode)->root;
5640 }
5641
5642 static struct inode *btrfs_iget_locked(struct super_block *s,
5643 struct btrfs_key *location,
5644 struct btrfs_root *root)
5645 {
5646 struct inode *inode;
5647 struct btrfs_iget_args args;
5648 unsigned long hashval = btrfs_inode_hash(location->objectid, root);
5649
5650 args.location = location;
5651 args.root = root;
5652
5653 inode = iget5_locked(s, hashval, btrfs_find_actor,
5654 btrfs_init_locked_inode,
5655 (void *)&args);
5656 return inode;
5657 }
5658
5659 /* Get an inode object given its location and corresponding root.
5660 * Returns in *is_new if the inode was read from disk
5661 */
5662 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
5663 struct btrfs_root *root, int *new)
5664 {
5665 struct inode *inode;
5666
5667 inode = btrfs_iget_locked(s, location, root);
5668 if (!inode)
5669 return ERR_PTR(-ENOMEM);
5670
5671 if (inode->i_state & I_NEW) {
5672 int ret;
5673
5674 ret = btrfs_read_locked_inode(inode);
5675 if (!ret) {
5676 inode_tree_add(inode);
5677 unlock_new_inode(inode);
5678 if (new)
5679 *new = 1;
5680 } else {
5681 iget_failed(inode);
5682 /*
5683 * ret > 0 can come from btrfs_search_slot called by
5684 * btrfs_read_locked_inode, this means the inode item
5685 * was not found.
5686 */
5687 if (ret > 0)
5688 ret = -ENOENT;
5689 inode = ERR_PTR(ret);
5690 }
5691 }
5692
5693 return inode;
5694 }
5695
5696 static struct inode *new_simple_dir(struct super_block *s,
5697 struct btrfs_key *key,
5698 struct btrfs_root *root)
5699 {
5700 struct inode *inode = new_inode(s);
5701
5702 if (!inode)
5703 return ERR_PTR(-ENOMEM);
5704
5705 BTRFS_I(inode)->root = root;
5706 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
5707 set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
5708
5709 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
5710 inode->i_op = &btrfs_dir_ro_inode_operations;
5711 inode->i_opflags &= ~IOP_XATTR;
5712 inode->i_fop = &simple_dir_operations;
5713 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
5714 inode->i_mtime = current_time(inode);
5715 inode->i_atime = inode->i_mtime;
5716 inode->i_ctime = inode->i_mtime;
5717 BTRFS_I(inode)->i_otime = inode->i_mtime;
5718
5719 return inode;
5720 }
5721
5722 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
5723 {
5724 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
5725 struct inode *inode;
5726 struct btrfs_root *root = BTRFS_I(dir)->root;
5727 struct btrfs_root *sub_root = root;
5728 struct btrfs_key location;
5729 int index;
5730 int ret = 0;
5731
5732 if (dentry->d_name.len > BTRFS_NAME_LEN)
5733 return ERR_PTR(-ENAMETOOLONG);
5734
5735 ret = btrfs_inode_by_name(dir, dentry, &location);
5736 if (ret < 0)
5737 return ERR_PTR(ret);
5738
5739 if (location.type == BTRFS_INODE_ITEM_KEY) {
5740 inode = btrfs_iget(dir->i_sb, &location, root, NULL);
5741 return inode;
5742 }
5743
5744 index = srcu_read_lock(&fs_info->subvol_srcu);
5745 ret = fixup_tree_root_location(fs_info, dir, dentry,
5746 &location, &sub_root);
5747 if (ret < 0) {
5748 if (ret != -ENOENT)
5749 inode = ERR_PTR(ret);
5750 else
5751 inode = new_simple_dir(dir->i_sb, &location, sub_root);
5752 } else {
5753 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL);
5754 }
5755 srcu_read_unlock(&fs_info->subvol_srcu, index);
5756
5757 if (!IS_ERR(inode) && root != sub_root) {
5758 down_read(&fs_info->cleanup_work_sem);
5759 if (!sb_rdonly(inode->i_sb))
5760 ret = btrfs_orphan_cleanup(sub_root);
5761 up_read(&fs_info->cleanup_work_sem);
5762 if (ret) {
5763 iput(inode);
5764 inode = ERR_PTR(ret);
5765 }
5766 }
5767
5768 return inode;
5769 }
5770
5771 static int btrfs_dentry_delete(const struct dentry *dentry)
5772 {
5773 struct btrfs_root *root;
5774 struct inode *inode = d_inode(dentry);
5775
5776 if (!inode && !IS_ROOT(dentry))
5777 inode = d_inode(dentry->d_parent);
5778
5779 if (inode) {
5780 root = BTRFS_I(inode)->root;
5781 if (btrfs_root_refs(&root->root_item) == 0)
5782 return 1;
5783
5784 if (btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
5785 return 1;
5786 }
5787 return 0;
5788 }
5789
5790 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
5791 unsigned int flags)
5792 {
5793 struct inode *inode;
5794
5795 inode = btrfs_lookup_dentry(dir, dentry);
5796 if (IS_ERR(inode)) {
5797 if (PTR_ERR(inode) == -ENOENT)
5798 inode = NULL;
5799 else
5800 return ERR_CAST(inode);
5801 }
5802
5803 return d_splice_alias(inode, dentry);
5804 }
5805
5806 unsigned char btrfs_filetype_table[] = {
5807 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
5808 };
5809
5810 /*
5811 * All this infrastructure exists because dir_emit can fault, and we are holding
5812 * the tree lock when doing readdir. For now just allocate a buffer and copy
5813 * our information into that, and then dir_emit from the buffer. This is
5814 * similar to what NFS does, only we don't keep the buffer around in pagecache
5815 * because I'm afraid I'll mess that up. Long term we need to make filldir do
5816 * copy_to_user_inatomic so we don't have to worry about page faulting under the
5817 * tree lock.
5818 */
5819 static int btrfs_opendir(struct inode *inode, struct file *file)
5820 {
5821 struct btrfs_file_private *private;
5822
5823 private = kzalloc(sizeof(struct btrfs_file_private), GFP_KERNEL);
5824 if (!private)
5825 return -ENOMEM;
5826 private->filldir_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
5827 if (!private->filldir_buf) {
5828 kfree(private);
5829 return -ENOMEM;
5830 }
5831 file->private_data = private;
5832 return 0;
5833 }
5834
5835 struct dir_entry {
5836 u64 ino;
5837 u64 offset;
5838 unsigned type;
5839 int name_len;
5840 };
5841
5842 static int btrfs_filldir(void *addr, int entries, struct dir_context *ctx)
5843 {
5844 while (entries--) {
5845 struct dir_entry *entry = addr;
5846 char *name = (char *)(entry + 1);
5847
5848 ctx->pos = get_unaligned(&entry->offset);
5849 if (!dir_emit(ctx, name, get_unaligned(&entry->name_len),
5850 get_unaligned(&entry->ino),
5851 get_unaligned(&entry->type)))
5852 return 1;
5853 addr += sizeof(struct dir_entry) +
5854 get_unaligned(&entry->name_len);
5855 ctx->pos++;
5856 }
5857 return 0;
5858 }
5859
5860 static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
5861 {
5862 struct inode *inode = file_inode(file);
5863 struct btrfs_root *root = BTRFS_I(inode)->root;
5864 struct btrfs_file_private *private = file->private_data;
5865 struct btrfs_dir_item *di;
5866 struct btrfs_key key;
5867 struct btrfs_key found_key;
5868 struct btrfs_path *path;
5869 void *addr;
5870 struct list_head ins_list;
5871 struct list_head del_list;
5872 int ret;
5873 struct extent_buffer *leaf;
5874 int slot;
5875 char *name_ptr;
5876 int name_len;
5877 int entries = 0;
5878 int total_len = 0;
5879 bool put = false;
5880 struct btrfs_key location;
5881
5882 if (!dir_emit_dots(file, ctx))
5883 return 0;
5884
5885 path = btrfs_alloc_path();
5886 if (!path)
5887 return -ENOMEM;
5888
5889 addr = private->filldir_buf;
5890 path->reada = READA_FORWARD;
5891
5892 INIT_LIST_HEAD(&ins_list);
5893 INIT_LIST_HEAD(&del_list);
5894 put = btrfs_readdir_get_delayed_items(inode, &ins_list, &del_list);
5895
5896 again:
5897 key.type = BTRFS_DIR_INDEX_KEY;
5898 key.offset = ctx->pos;
5899 key.objectid = btrfs_ino(BTRFS_I(inode));
5900
5901 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5902 if (ret < 0)
5903 goto err;
5904
5905 while (1) {
5906 struct dir_entry *entry;
5907
5908 leaf = path->nodes[0];
5909 slot = path->slots[0];
5910 if (slot >= btrfs_header_nritems(leaf)) {
5911 ret = btrfs_next_leaf(root, path);
5912 if (ret < 0)
5913 goto err;
5914 else if (ret > 0)
5915 break;
5916 continue;
5917 }
5918
5919 btrfs_item_key_to_cpu(leaf, &found_key, slot);
5920
5921 if (found_key.objectid != key.objectid)
5922 break;
5923 if (found_key.type != BTRFS_DIR_INDEX_KEY)
5924 break;
5925 if (found_key.offset < ctx->pos)
5926 goto next;
5927 if (btrfs_should_delete_dir_index(&del_list, found_key.offset))
5928 goto next;
5929 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
5930 name_len = btrfs_dir_name_len(leaf, di);
5931 if ((total_len + sizeof(struct dir_entry) + name_len) >=
5932 PAGE_SIZE) {
5933 btrfs_release_path(path);
5934 ret = btrfs_filldir(private->filldir_buf, entries, ctx);
5935 if (ret)
5936 goto nopos;
5937 addr = private->filldir_buf;
5938 entries = 0;
5939 total_len = 0;
5940 goto again;
5941 }
5942
5943 entry = addr;
5944 put_unaligned(name_len, &entry->name_len);
5945 name_ptr = (char *)(entry + 1);
5946 read_extent_buffer(leaf, name_ptr, (unsigned long)(di + 1),
5947 name_len);
5948 put_unaligned(btrfs_filetype_table[btrfs_dir_type(leaf, di)],
5949 &entry->type);
5950 btrfs_dir_item_key_to_cpu(leaf, di, &location);
5951 put_unaligned(location.objectid, &entry->ino);
5952 put_unaligned(found_key.offset, &entry->offset);
5953 entries++;
5954 addr += sizeof(struct dir_entry) + name_len;
5955 total_len += sizeof(struct dir_entry) + name_len;
5956 next:
5957 path->slots[0]++;
5958 }
5959 btrfs_release_path(path);
5960
5961 ret = btrfs_filldir(private->filldir_buf, entries, ctx);
5962 if (ret)
5963 goto nopos;
5964
5965 ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list);
5966 if (ret)
5967 goto nopos;
5968
5969 /*
5970 * Stop new entries from being returned after we return the last
5971 * entry.
5972 *
5973 * New directory entries are assigned a strictly increasing
5974 * offset. This means that new entries created during readdir
5975 * are *guaranteed* to be seen in the future by that readdir.
5976 * This has broken buggy programs which operate on names as
5977 * they're returned by readdir. Until we re-use freed offsets
5978 * we have this hack to stop new entries from being returned
5979 * under the assumption that they'll never reach this huge
5980 * offset.
5981 *
5982 * This is being careful not to overflow 32bit loff_t unless the
5983 * last entry requires it because doing so has broken 32bit apps
5984 * in the past.
5985 */
5986 if (ctx->pos >= INT_MAX)
5987 ctx->pos = LLONG_MAX;
5988 else
5989 ctx->pos = INT_MAX;
5990 nopos:
5991 ret = 0;
5992 err:
5993 if (put)
5994 btrfs_readdir_put_delayed_items(inode, &ins_list, &del_list);
5995 btrfs_free_path(path);
5996 return ret;
5997 }
5998
5999 /*
6000 * This is somewhat expensive, updating the tree every time the
6001 * inode changes. But, it is most likely to find the inode in cache.
6002 * FIXME, needs more benchmarking...there are no reasons other than performance
6003 * to keep or drop this code.
6004 */
6005 static int btrfs_dirty_inode(struct inode *inode)
6006 {
6007 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
6008 struct btrfs_root *root = BTRFS_I(inode)->root;
6009 struct btrfs_trans_handle *trans;
6010 int ret;
6011
6012 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags))
6013 return 0;
6014
6015 trans = btrfs_join_transaction(root);
6016 if (IS_ERR(trans))
6017 return PTR_ERR(trans);
6018
6019 ret = btrfs_update_inode(trans, root, inode);
6020 if (ret && ret == -ENOSPC) {
6021 /* whoops, lets try again with the full transaction */
6022 btrfs_end_transaction(trans);
6023 trans = btrfs_start_transaction(root, 1);
6024 if (IS_ERR(trans))
6025 return PTR_ERR(trans);
6026
6027 ret = btrfs_update_inode(trans, root, inode);
6028 }
6029 btrfs_end_transaction(trans);
6030 if (BTRFS_I(inode)->delayed_node)
6031 btrfs_balance_delayed_items(fs_info);
6032
6033 return ret;
6034 }
6035
6036 /*
6037 * This is a copy of file_update_time. We need this so we can return error on
6038 * ENOSPC for updating the inode in the case of file write and mmap writes.
6039 */
6040 static int btrfs_update_time(struct inode *inode, struct timespec64 *now,
6041 int flags)
6042 {
6043 struct btrfs_root *root = BTRFS_I(inode)->root;
6044 bool dirty = flags & ~S_VERSION;
6045
6046 if (btrfs_root_readonly(root))
6047 return -EROFS;
6048
6049 if (flags & S_VERSION)
6050 dirty |= inode_maybe_inc_iversion(inode, dirty);
6051 if (flags & S_CTIME)
6052 inode->i_ctime = *now;
6053 if (flags & S_MTIME)
6054 inode->i_mtime = *now;
6055 if (flags & S_ATIME)
6056 inode->i_atime = *now;
6057 return dirty ? btrfs_dirty_inode(inode) : 0;
6058 }
6059
6060 /*
6061 * find the highest existing sequence number in a directory
6062 * and then set the in-memory index_cnt variable to reflect
6063 * free sequence numbers
6064 */
6065 static int btrfs_set_inode_index_count(struct btrfs_inode *inode)
6066 {
6067 struct btrfs_root *root = inode->root;
6068 struct btrfs_key key, found_key;
6069 struct btrfs_path *path;
6070 struct extent_buffer *leaf;
6071 int ret;
6072
6073 key.objectid = btrfs_ino(inode);
6074 key.type = BTRFS_DIR_INDEX_KEY;
6075 key.offset = (u64)-1;
6076
6077 path = btrfs_alloc_path();
6078 if (!path)
6079 return -ENOMEM;
6080
6081 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6082 if (ret < 0)
6083 goto out;
6084 /* FIXME: we should be able to handle this */
6085 if (ret == 0)
6086 goto out;
6087 ret = 0;
6088
6089 /*
6090 * MAGIC NUMBER EXPLANATION:
6091 * since we search a directory based on f_pos we have to start at 2
6092 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
6093 * else has to start at 2
6094 */
6095 if (path->slots[0] == 0) {
6096 inode->index_cnt = 2;
6097 goto out;
6098 }
6099
6100 path->slots[0]--;
6101
6102 leaf = path->nodes[0];
6103 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6104
6105 if (found_key.objectid != btrfs_ino(inode) ||
6106 found_key.type != BTRFS_DIR_INDEX_KEY) {
6107 inode->index_cnt = 2;
6108 goto out;
6109 }
6110
6111 inode->index_cnt = found_key.offset + 1;
6112 out:
6113 btrfs_free_path(path);
6114 return ret;
6115 }
6116
6117 /*
6118 * helper to find a free sequence number in a given directory. This current
6119 * code is very simple, later versions will do smarter things in the btree
6120 */
6121 int btrfs_set_inode_index(struct btrfs_inode *dir, u64 *index)
6122 {
6123 int ret = 0;
6124
6125 if (dir->index_cnt == (u64)-1) {
6126 ret = btrfs_inode_delayed_dir_index_count(dir);
6127 if (ret) {
6128 ret = btrfs_set_inode_index_count(dir);
6129 if (ret)
6130 return ret;
6131 }
6132 }
6133
6134 *index = dir->index_cnt;
6135 dir->index_cnt++;
6136
6137 return ret;
6138 }
6139
6140 static int btrfs_insert_inode_locked(struct inode *inode)
6141 {
6142 struct btrfs_iget_args args;
6143 args.location = &BTRFS_I(inode)->location;
6144 args.root = BTRFS_I(inode)->root;
6145
6146 return insert_inode_locked4(inode,
6147 btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root),
6148 btrfs_find_actor, &args);
6149 }
6150
6151 /*
6152 * Inherit flags from the parent inode.
6153 *
6154 * Currently only the compression flags and the cow flags are inherited.
6155 */
6156 static void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
6157 {
6158 unsigned int flags;
6159
6160 if (!dir)
6161 return;
6162
6163 flags = BTRFS_I(dir)->flags;
6164
6165 if (flags & BTRFS_INODE_NOCOMPRESS) {
6166 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
6167 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
6168 } else if (flags & BTRFS_INODE_COMPRESS) {
6169 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
6170 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
6171 }
6172
6173 if (flags & BTRFS_INODE_NODATACOW) {
6174 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
6175 if (S_ISREG(inode->i_mode))
6176 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
6177 }
6178
6179 btrfs_sync_inode_flags_to_i_flags(inode);
6180 }
6181
6182 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
6183 struct btrfs_root *root,
6184 struct inode *dir,
6185 const char *name, int name_len,
6186 u64 ref_objectid, u64 objectid,
6187 umode_t mode, u64 *index)
6188 {
6189 struct btrfs_fs_info *fs_info = root->fs_info;
6190 struct inode *inode;
6191 struct btrfs_inode_item *inode_item;
6192 struct btrfs_key *location;
6193 struct btrfs_path *path;
6194 struct btrfs_inode_ref *ref;
6195 struct btrfs_key key[2];
6196 u32 sizes[2];
6197 int nitems = name ? 2 : 1;
6198 unsigned long ptr;
6199 int ret;
6200
6201 path = btrfs_alloc_path();
6202 if (!path)
6203 return ERR_PTR(-ENOMEM);
6204
6205 inode = new_inode(fs_info->sb);
6206 if (!inode) {
6207 btrfs_free_path(path);
6208 return ERR_PTR(-ENOMEM);
6209 }
6210
6211 /*
6212 * O_TMPFILE, set link count to 0, so that after this point,
6213 * we fill in an inode item with the correct link count.
6214 */
6215 if (!name)
6216 set_nlink(inode, 0);
6217
6218 /*
6219 * we have to initialize this early, so we can reclaim the inode
6220 * number if we fail afterwards in this function.
6221 */
6222 inode->i_ino = objectid;
6223
6224 if (dir && name) {
6225 trace_btrfs_inode_request(dir);
6226
6227 ret = btrfs_set_inode_index(BTRFS_I(dir), index);
6228 if (ret) {
6229 btrfs_free_path(path);
6230 iput(inode);
6231 return ERR_PTR(ret);
6232 }
6233 } else if (dir) {
6234 *index = 0;
6235 }
6236 /*
6237 * index_cnt is ignored for everything but a dir,
6238 * btrfs_set_inode_index_count has an explanation for the magic
6239 * number
6240 */
6241 BTRFS_I(inode)->index_cnt = 2;
6242 BTRFS_I(inode)->dir_index = *index;
6243 BTRFS_I(inode)->root = root;
6244 BTRFS_I(inode)->generation = trans->transid;
6245 inode->i_generation = BTRFS_I(inode)->generation;
6246
6247 /*
6248 * We could have gotten an inode number from somebody who was fsynced
6249 * and then removed in this same transaction, so let's just set full
6250 * sync since it will be a full sync anyway and this will blow away the
6251 * old info in the log.
6252 */
6253 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
6254
6255 key[0].objectid = objectid;
6256 key[0].type = BTRFS_INODE_ITEM_KEY;
6257 key[0].offset = 0;
6258
6259 sizes[0] = sizeof(struct btrfs_inode_item);
6260
6261 if (name) {
6262 /*
6263 * Start new inodes with an inode_ref. This is slightly more
6264 * efficient for small numbers of hard links since they will
6265 * be packed into one item. Extended refs will kick in if we
6266 * add more hard links than can fit in the ref item.
6267 */
6268 key[1].objectid = objectid;
6269 key[1].type = BTRFS_INODE_REF_KEY;
6270 key[1].offset = ref_objectid;
6271
6272 sizes[1] = name_len + sizeof(*ref);
6273 }
6274
6275 location = &BTRFS_I(inode)->location;
6276 location->objectid = objectid;
6277 location->offset = 0;
6278 location->type = BTRFS_INODE_ITEM_KEY;
6279
6280 ret = btrfs_insert_inode_locked(inode);
6281 if (ret < 0) {
6282 iput(inode);
6283 goto fail;
6284 }
6285
6286 path->leave_spinning = 1;
6287 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, nitems);
6288 if (ret != 0)
6289 goto fail_unlock;
6290
6291 inode_init_owner(inode, dir, mode);
6292 inode_set_bytes(inode, 0);
6293
6294 inode->i_mtime = current_time(inode);
6295 inode->i_atime = inode->i_mtime;
6296 inode->i_ctime = inode->i_mtime;
6297 BTRFS_I(inode)->i_otime = inode->i_mtime;
6298
6299 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
6300 struct btrfs_inode_item);
6301 memzero_extent_buffer(path->nodes[0], (unsigned long)inode_item,
6302 sizeof(*inode_item));
6303 fill_inode_item(trans, path->nodes[0], inode_item, inode);
6304
6305 if (name) {
6306 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
6307 struct btrfs_inode_ref);
6308 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
6309 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
6310 ptr = (unsigned long)(ref + 1);
6311 write_extent_buffer(path->nodes[0], name, ptr, name_len);
6312 }
6313
6314 btrfs_mark_buffer_dirty(path->nodes[0]);
6315 btrfs_free_path(path);
6316
6317 btrfs_inherit_iflags(inode, dir);
6318
6319 if (S_ISREG(mode)) {
6320 if (btrfs_test_opt(fs_info, NODATASUM))
6321 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
6322 if (btrfs_test_opt(fs_info, NODATACOW))
6323 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW |
6324 BTRFS_INODE_NODATASUM;
6325 }
6326
6327 inode_tree_add(inode);
6328
6329 trace_btrfs_inode_new(inode);
6330 btrfs_set_inode_last_trans(trans, inode);
6331
6332 btrfs_update_root_times(trans, root);
6333
6334 ret = btrfs_inode_inherit_props(trans, inode, dir);
6335 if (ret)
6336 btrfs_err(fs_info,
6337 "error inheriting props for ino %llu (root %llu): %d",
6338 btrfs_ino(BTRFS_I(inode)), root->root_key.objectid, ret);
6339
6340 return inode;
6341
6342 fail_unlock:
6343 discard_new_inode(inode);
6344 fail:
6345 if (dir && name)
6346 BTRFS_I(dir)->index_cnt--;
6347 btrfs_free_path(path);
6348 return ERR_PTR(ret);
6349 }
6350
6351 static inline u8 btrfs_inode_type(struct inode *inode)
6352 {
6353 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
6354 }
6355
6356 /*
6357 * utility function to add 'inode' into 'parent_inode' with
6358 * a give name and a given sequence number.
6359 * if 'add_backref' is true, also insert a backref from the
6360 * inode to the parent directory.
6361 */
6362 int btrfs_add_link(struct btrfs_trans_handle *trans,
6363 struct btrfs_inode *parent_inode, struct btrfs_inode *inode,
6364 const char *name, int name_len, int add_backref, u64 index)
6365 {
6366 int ret = 0;
6367 struct btrfs_key key;
6368 struct btrfs_root *root = parent_inode->root;
6369 u64 ino = btrfs_ino(inode);
6370 u64 parent_ino = btrfs_ino(parent_inode);
6371
6372 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
6373 memcpy(&key, &inode->root->root_key, sizeof(key));
6374 } else {
6375 key.objectid = ino;
6376 key.type = BTRFS_INODE_ITEM_KEY;
6377 key.offset = 0;
6378 }
6379
6380 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
6381 ret = btrfs_add_root_ref(trans, key.objectid,
6382 root->root_key.objectid, parent_ino,
6383 index, name, name_len);
6384 } else if (add_backref) {
6385 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino,
6386 parent_ino, index);
6387 }
6388
6389 /* Nothing to clean up yet */
6390 if (ret)
6391 return ret;
6392
6393 ret = btrfs_insert_dir_item(trans, root, name, name_len,
6394 parent_inode, &key,
6395 btrfs_inode_type(&inode->vfs_inode), index);
6396 if (ret == -EEXIST || ret == -EOVERFLOW)
6397 goto fail_dir_item;
6398 else if (ret) {
6399 btrfs_abort_transaction(trans, ret);
6400 return ret;
6401 }
6402
6403 btrfs_i_size_write(parent_inode, parent_inode->vfs_inode.i_size +
6404 name_len * 2);
6405 inode_inc_iversion(&parent_inode->vfs_inode);
6406 parent_inode->vfs_inode.i_mtime = parent_inode->vfs_inode.i_ctime =
6407 current_time(&parent_inode->vfs_inode);
6408 ret = btrfs_update_inode(trans, root, &parent_inode->vfs_inode);
6409 if (ret)
6410 btrfs_abort_transaction(trans, ret);
6411 return ret;
6412
6413 fail_dir_item:
6414 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
6415 u64 local_index;
6416 int err;
6417 err = btrfs_del_root_ref(trans, key.objectid,
6418 root->root_key.objectid, parent_ino,
6419 &local_index, name, name_len);
6420
6421 } else if (add_backref) {
6422 u64 local_index;
6423 int err;
6424
6425 err = btrfs_del_inode_ref(trans, root, name, name_len,
6426 ino, parent_ino, &local_index);
6427 }
6428 return ret;
6429 }
6430
6431 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
6432 struct btrfs_inode *dir, struct dentry *dentry,
6433 struct btrfs_inode *inode, int backref, u64 index)
6434 {
6435 int err = btrfs_add_link(trans, dir, inode,
6436 dentry->d_name.name, dentry->d_name.len,
6437 backref, index);
6438 if (err > 0)
6439 err = -EEXIST;
6440 return err;
6441 }
6442
6443 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
6444 umode_t mode, dev_t rdev)
6445 {
6446 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
6447 struct btrfs_trans_handle *trans;
6448 struct btrfs_root *root = BTRFS_I(dir)->root;
6449 struct inode *inode = NULL;
6450 int err;
6451 u64 objectid;
6452 u64 index = 0;
6453
6454 /*
6455 * 2 for inode item and ref
6456 * 2 for dir items
6457 * 1 for xattr if selinux is on
6458 */
6459 trans = btrfs_start_transaction(root, 5);
6460 if (IS_ERR(trans))
6461 return PTR_ERR(trans);
6462
6463 err = btrfs_find_free_ino(root, &objectid);
6464 if (err)
6465 goto out_unlock;
6466
6467 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
6468 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid,
6469 mode, &index);
6470 if (IS_ERR(inode)) {
6471 err = PTR_ERR(inode);
6472 inode = NULL;
6473 goto out_unlock;
6474 }
6475
6476 /*
6477 * If the active LSM wants to access the inode during
6478 * d_instantiate it needs these. Smack checks to see
6479 * if the filesystem supports xattrs by looking at the
6480 * ops vector.
6481 */
6482 inode->i_op = &btrfs_special_inode_operations;
6483 init_special_inode(inode, inode->i_mode, rdev);
6484
6485 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
6486 if (err)
6487 goto out_unlock;
6488
6489 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode),
6490 0, index);
6491 if (err)
6492 goto out_unlock;
6493
6494 btrfs_update_inode(trans, root, inode);
6495 d_instantiate_new(dentry, inode);
6496
6497 out_unlock:
6498 btrfs_end_transaction(trans);
6499 btrfs_btree_balance_dirty(fs_info);
6500 if (err && inode) {
6501 inode_dec_link_count(inode);
6502 discard_new_inode(inode);
6503 }
6504 return err;
6505 }
6506
6507 static int btrfs_create(struct inode *dir, struct dentry *dentry,
6508 umode_t mode, bool excl)
6509 {
6510 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
6511 struct btrfs_trans_handle *trans;
6512 struct btrfs_root *root = BTRFS_I(dir)->root;
6513 struct inode *inode = NULL;
6514 int err;
6515 u64 objectid;
6516 u64 index = 0;
6517
6518 /*
6519 * 2 for inode item and ref
6520 * 2 for dir items
6521 * 1 for xattr if selinux is on
6522 */
6523 trans = btrfs_start_transaction(root, 5);
6524 if (IS_ERR(trans))
6525 return PTR_ERR(trans);
6526
6527 err = btrfs_find_free_ino(root, &objectid);
6528 if (err)
6529 goto out_unlock;
6530
6531 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
6532 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid,
6533 mode, &index);
6534 if (IS_ERR(inode)) {
6535 err = PTR_ERR(inode);
6536 inode = NULL;
6537 goto out_unlock;
6538 }
6539 /*
6540 * If the active LSM wants to access the inode during
6541 * d_instantiate it needs these. Smack checks to see
6542 * if the filesystem supports xattrs by looking at the
6543 * ops vector.
6544 */
6545 inode->i_fop = &btrfs_file_operations;
6546 inode->i_op = &btrfs_file_inode_operations;
6547 inode->i_mapping->a_ops = &btrfs_aops;
6548
6549 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
6550 if (err)
6551 goto out_unlock;
6552
6553 err = btrfs_update_inode(trans, root, inode);
6554 if (err)
6555 goto out_unlock;
6556
6557 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode),
6558 0, index);
6559 if (err)
6560 goto out_unlock;
6561
6562 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
6563 d_instantiate_new(dentry, inode);
6564
6565 out_unlock:
6566 btrfs_end_transaction(trans);
6567 if (err && inode) {
6568 inode_dec_link_count(inode);
6569 discard_new_inode(inode);
6570 }
6571 btrfs_btree_balance_dirty(fs_info);
6572 return err;
6573 }
6574
6575 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
6576 struct dentry *dentry)
6577 {
6578 struct btrfs_trans_handle *trans = NULL;
6579 struct btrfs_root *root = BTRFS_I(dir)->root;
6580 struct inode *inode = d_inode(old_dentry);
6581 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
6582 u64 index;
6583 int err;
6584 int drop_inode = 0;
6585
6586 /* do not allow sys_link's with other subvols of the same device */
6587 if (root->objectid != BTRFS_I(inode)->root->objectid)
6588 return -EXDEV;
6589
6590 if (inode->i_nlink >= BTRFS_LINK_MAX)
6591 return -EMLINK;
6592
6593 err = btrfs_set_inode_index(BTRFS_I(dir), &index);
6594 if (err)
6595 goto fail;
6596
6597 /*
6598 * 2 items for inode and inode ref
6599 * 2 items for dir items
6600 * 1 item for parent inode
6601 * 1 item for orphan item deletion if O_TMPFILE
6602 */
6603 trans = btrfs_start_transaction(root, inode->i_nlink ? 5 : 6);
6604 if (IS_ERR(trans)) {
6605 err = PTR_ERR(trans);
6606 trans = NULL;
6607 goto fail;
6608 }
6609
6610 /* There are several dir indexes for this inode, clear the cache. */
6611 BTRFS_I(inode)->dir_index = 0ULL;
6612 inc_nlink(inode);
6613 inode_inc_iversion(inode);
6614 inode->i_ctime = current_time(inode);
6615 ihold(inode);
6616 set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags);
6617
6618 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode),
6619 1, index);
6620
6621 if (err) {
6622 drop_inode = 1;
6623 } else {
6624 struct dentry *parent = dentry->d_parent;
6625 int ret;
6626
6627 err = btrfs_update_inode(trans, root, inode);
6628 if (err)
6629 goto fail;
6630 if (inode->i_nlink == 1) {
6631 /*
6632 * If new hard link count is 1, it's a file created
6633 * with open(2) O_TMPFILE flag.
6634 */
6635 err = btrfs_orphan_del(trans, BTRFS_I(inode));
6636 if (err)
6637 goto fail;
6638 }
6639 d_instantiate(dentry, inode);
6640 ret = btrfs_log_new_name(trans, BTRFS_I(inode), NULL, parent,
6641 true, NULL);
6642 if (ret == BTRFS_NEED_TRANS_COMMIT) {
6643 err = btrfs_commit_transaction(trans);
6644 trans = NULL;
6645 }
6646 }
6647
6648 fail:
6649 if (trans)
6650 btrfs_end_transaction(trans);
6651 if (drop_inode) {
6652 inode_dec_link_count(inode);
6653 iput(inode);
6654 }
6655 btrfs_btree_balance_dirty(fs_info);
6656 return err;
6657 }
6658
6659 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
6660 {
6661 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
6662 struct inode *inode = NULL;
6663 struct btrfs_trans_handle *trans;
6664 struct btrfs_root *root = BTRFS_I(dir)->root;
6665 int err = 0;
6666 int drop_on_err = 0;
6667 u64 objectid = 0;
6668 u64 index = 0;
6669
6670 /*
6671 * 2 items for inode and ref
6672 * 2 items for dir items
6673 * 1 for xattr if selinux is on
6674 */
6675 trans = btrfs_start_transaction(root, 5);
6676 if (IS_ERR(trans))
6677 return PTR_ERR(trans);
6678
6679 err = btrfs_find_free_ino(root, &objectid);
6680 if (err)
6681 goto out_fail;
6682
6683 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
6684 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid,
6685 S_IFDIR | mode, &index);
6686 if (IS_ERR(inode)) {
6687 err = PTR_ERR(inode);
6688 inode = NULL;
6689 goto out_fail;
6690 }
6691
6692 drop_on_err = 1;
6693 /* these must be set before we unlock the inode */
6694 inode->i_op = &btrfs_dir_inode_operations;
6695 inode->i_fop = &btrfs_dir_file_operations;
6696
6697 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
6698 if (err)
6699 goto out_fail;
6700
6701 btrfs_i_size_write(BTRFS_I(inode), 0);
6702 err = btrfs_update_inode(trans, root, inode);
6703 if (err)
6704 goto out_fail;
6705
6706 err = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode),
6707 dentry->d_name.name,
6708 dentry->d_name.len, 0, index);
6709 if (err)
6710 goto out_fail;
6711
6712 d_instantiate_new(dentry, inode);
6713 drop_on_err = 0;
6714
6715 out_fail:
6716 btrfs_end_transaction(trans);
6717 if (err && inode) {
6718 inode_dec_link_count(inode);
6719 discard_new_inode(inode);
6720 }
6721 btrfs_btree_balance_dirty(fs_info);
6722 return err;
6723 }
6724
6725 static noinline int uncompress_inline(struct btrfs_path *path,
6726 struct page *page,
6727 size_t pg_offset, u64 extent_offset,
6728 struct btrfs_file_extent_item *item)
6729 {
6730 int ret;
6731 struct extent_buffer *leaf = path->nodes[0];
6732 char *tmp;
6733 size_t max_size;
6734 unsigned long inline_size;
6735 unsigned long ptr;
6736 int compress_type;
6737
6738 WARN_ON(pg_offset != 0);
6739 compress_type = btrfs_file_extent_compression(leaf, item);
6740 max_size = btrfs_file_extent_ram_bytes(leaf, item);
6741 inline_size = btrfs_file_extent_inline_item_len(leaf,
6742 btrfs_item_nr(path->slots[0]));
6743 tmp = kmalloc(inline_size, GFP_NOFS);
6744 if (!tmp)
6745 return -ENOMEM;
6746 ptr = btrfs_file_extent_inline_start(item);
6747
6748 read_extent_buffer(leaf, tmp, ptr, inline_size);
6749
6750 max_size = min_t(unsigned long, PAGE_SIZE, max_size);
6751 ret = btrfs_decompress(compress_type, tmp, page,
6752 extent_offset, inline_size, max_size);
6753
6754 /*
6755 * decompression code contains a memset to fill in any space between the end
6756 * of the uncompressed data and the end of max_size in case the decompressed
6757 * data ends up shorter than ram_bytes. That doesn't cover the hole between
6758 * the end of an inline extent and the beginning of the next block, so we
6759 * cover that region here.
6760 */
6761
6762 if (max_size + pg_offset < PAGE_SIZE) {
6763 char *map = kmap(page);
6764 memset(map + pg_offset + max_size, 0, PAGE_SIZE - max_size - pg_offset);
6765 kunmap(page);
6766 }
6767 kfree(tmp);
6768 return ret;
6769 }
6770
6771 /*
6772 * a bit scary, this does extent mapping from logical file offset to the disk.
6773 * the ugly parts come from merging extents from the disk with the in-ram
6774 * representation. This gets more complex because of the data=ordered code,
6775 * where the in-ram extents might be locked pending data=ordered completion.
6776 *
6777 * This also copies inline extents directly into the page.
6778 */
6779 struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
6780 struct page *page,
6781 size_t pg_offset, u64 start, u64 len,
6782 int create)
6783 {
6784 struct btrfs_fs_info *fs_info = inode->root->fs_info;
6785 int ret;
6786 int err = 0;
6787 u64 extent_start = 0;
6788 u64 extent_end = 0;
6789 u64 objectid = btrfs_ino(inode);
6790 u32 found_type;
6791 struct btrfs_path *path = NULL;
6792 struct btrfs_root *root = inode->root;
6793 struct btrfs_file_extent_item *item;
6794 struct extent_buffer *leaf;
6795 struct btrfs_key found_key;
6796 struct extent_map *em = NULL;
6797 struct extent_map_tree *em_tree = &inode->extent_tree;
6798 struct extent_io_tree *io_tree = &inode->io_tree;
6799 const bool new_inline = !page || create;
6800
6801 read_lock(&em_tree->lock);
6802 em = lookup_extent_mapping(em_tree, start, len);
6803 if (em)
6804 em->bdev = fs_info->fs_devices->latest_bdev;
6805 read_unlock(&em_tree->lock);
6806
6807 if (em) {
6808 if (em->start > start || em->start + em->len <= start)
6809 free_extent_map(em);
6810 else if (em->block_start == EXTENT_MAP_INLINE && page)
6811 free_extent_map(em);
6812 else
6813 goto out;
6814 }
6815 em = alloc_extent_map();
6816 if (!em) {
6817 err = -ENOMEM;
6818 goto out;
6819 }
6820 em->bdev = fs_info->fs_devices->latest_bdev;
6821 em->start = EXTENT_MAP_HOLE;
6822 em->orig_start = EXTENT_MAP_HOLE;
6823 em->len = (u64)-1;
6824 em->block_len = (u64)-1;
6825
6826 if (!path) {
6827 path = btrfs_alloc_path();
6828 if (!path) {
6829 err = -ENOMEM;
6830 goto out;
6831 }
6832 /*
6833 * Chances are we'll be called again, so go ahead and do
6834 * readahead
6835 */
6836 path->reada = READA_FORWARD;
6837 }
6838
6839 ret = btrfs_lookup_file_extent(NULL, root, path, objectid, start, 0);
6840 if (ret < 0) {
6841 err = ret;
6842 goto out;
6843 }
6844
6845 if (ret != 0) {
6846 if (path->slots[0] == 0)
6847 goto not_found;
6848 path->slots[0]--;
6849 }
6850
6851 leaf = path->nodes[0];
6852 item = btrfs_item_ptr(leaf, path->slots[0],
6853 struct btrfs_file_extent_item);
6854 /* are we inside the extent that was found? */
6855 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6856 found_type = found_key.type;
6857 if (found_key.objectid != objectid ||
6858 found_type != BTRFS_EXTENT_DATA_KEY) {
6859 /*
6860 * If we backup past the first extent we want to move forward
6861 * and see if there is an extent in front of us, otherwise we'll
6862 * say there is a hole for our whole search range which can
6863 * cause problems.
6864 */
6865 extent_end = start;
6866 goto next;
6867 }
6868
6869 found_type = btrfs_file_extent_type(leaf, item);
6870 extent_start = found_key.offset;
6871 if (found_type == BTRFS_FILE_EXTENT_REG ||
6872 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
6873 extent_end = extent_start +
6874 btrfs_file_extent_num_bytes(leaf, item);
6875
6876 trace_btrfs_get_extent_show_fi_regular(inode, leaf, item,
6877 extent_start);
6878 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
6879 size_t size;
6880
6881 size = btrfs_file_extent_ram_bytes(leaf, item);
6882 extent_end = ALIGN(extent_start + size,
6883 fs_info->sectorsize);
6884
6885 trace_btrfs_get_extent_show_fi_inline(inode, leaf, item,
6886 path->slots[0],
6887 extent_start);
6888 }
6889 next:
6890 if (start >= extent_end) {
6891 path->slots[0]++;
6892 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
6893 ret = btrfs_next_leaf(root, path);
6894 if (ret < 0) {
6895 err = ret;
6896 goto out;
6897 }
6898 if (ret > 0)
6899 goto not_found;
6900 leaf = path->nodes[0];
6901 }
6902 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6903 if (found_key.objectid != objectid ||
6904 found_key.type != BTRFS_EXTENT_DATA_KEY)
6905 goto not_found;
6906 if (start + len <= found_key.offset)
6907 goto not_found;
6908 if (start > found_key.offset)
6909 goto next;
6910 em->start = start;
6911 em->orig_start = start;
6912 em->len = found_key.offset - start;
6913 goto not_found_em;
6914 }
6915
6916 btrfs_extent_item_to_extent_map(inode, path, item,
6917 new_inline, em);
6918
6919 if (found_type == BTRFS_FILE_EXTENT_REG ||
6920 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
6921 goto insert;
6922 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
6923 unsigned long ptr;
6924 char *map;
6925 size_t size;
6926 size_t extent_offset;
6927 size_t copy_size;
6928
6929 if (new_inline)
6930 goto out;
6931
6932 size = btrfs_file_extent_ram_bytes(leaf, item);
6933 extent_offset = page_offset(page) + pg_offset - extent_start;
6934 copy_size = min_t(u64, PAGE_SIZE - pg_offset,
6935 size - extent_offset);
6936 em->start = extent_start + extent_offset;
6937 em->len = ALIGN(copy_size, fs_info->sectorsize);
6938 em->orig_block_len = em->len;
6939 em->orig_start = em->start;
6940 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
6941 if (!PageUptodate(page)) {
6942 if (btrfs_file_extent_compression(leaf, item) !=
6943 BTRFS_COMPRESS_NONE) {
6944 ret = uncompress_inline(path, page, pg_offset,
6945 extent_offset, item);
6946 if (ret) {
6947 err = ret;
6948 goto out;
6949 }
6950 } else {
6951 map = kmap(page);
6952 read_extent_buffer(leaf, map + pg_offset, ptr,
6953 copy_size);
6954 if (pg_offset + copy_size < PAGE_SIZE) {
6955 memset(map + pg_offset + copy_size, 0,
6956 PAGE_SIZE - pg_offset -
6957 copy_size);
6958 }
6959 kunmap(page);
6960 }
6961 flush_dcache_page(page);
6962 }
6963 set_extent_uptodate(io_tree, em->start,
6964 extent_map_end(em) - 1, NULL, GFP_NOFS);
6965 goto insert;
6966 }
6967 not_found:
6968 em->start = start;
6969 em->orig_start = start;
6970 em->len = len;
6971 not_found_em:
6972 em->block_start = EXTENT_MAP_HOLE;
6973 insert:
6974 btrfs_release_path(path);
6975 if (em->start > start || extent_map_end(em) <= start) {
6976 btrfs_err(fs_info,
6977 "bad extent! em: [%llu %llu] passed [%llu %llu]",
6978 em->start, em->len, start, len);
6979 err = -EIO;
6980 goto out;
6981 }
6982
6983 err = 0;
6984 write_lock(&em_tree->lock);
6985 err = btrfs_add_extent_mapping(fs_info, em_tree, &em, start, len);
6986 write_unlock(&em_tree->lock);
6987 out:
6988
6989 trace_btrfs_get_extent(root, inode, em);
6990
6991 btrfs_free_path(path);
6992 if (err) {
6993 free_extent_map(em);
6994 return ERR_PTR(err);
6995 }
6996 BUG_ON(!em); /* Error is always set */
6997 return em;
6998 }
6999
7000 struct extent_map *btrfs_get_extent_fiemap(struct btrfs_inode *inode,
7001 struct page *page,
7002 size_t pg_offset, u64 start, u64 len,
7003 int create)
7004 {
7005 struct extent_map *em;
7006 struct extent_map *hole_em = NULL;
7007 u64 range_start = start;
7008 u64 end;
7009 u64 found;
7010 u64 found_end;
7011 int err = 0;
7012
7013 em = btrfs_get_extent(inode, page, pg_offset, start, len, create);
7014 if (IS_ERR(em))
7015 return em;
7016 /*
7017 * If our em maps to:
7018 * - a hole or
7019 * - a pre-alloc extent,
7020 * there might actually be delalloc bytes behind it.
7021 */
7022 if (em->block_start != EXTENT_MAP_HOLE &&
7023 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
7024 return em;
7025 else
7026 hole_em = em;
7027
7028 /* check to see if we've wrapped (len == -1 or similar) */
7029 end = start + len;
7030 if (end < start)
7031 end = (u64)-1;
7032 else
7033 end -= 1;
7034
7035 em = NULL;
7036
7037 /* ok, we didn't find anything, lets look for delalloc */
7038 found = count_range_bits(&inode->io_tree, &range_start,
7039 end, len, EXTENT_DELALLOC, 1);
7040 found_end = range_start + found;
7041 if (found_end < range_start)
7042 found_end = (u64)-1;
7043
7044 /*
7045 * we didn't find anything useful, return
7046 * the original results from get_extent()
7047 */
7048 if (range_start > end || found_end <= start) {
7049 em = hole_em;
7050 hole_em = NULL;
7051 goto out;
7052 }
7053
7054 /* adjust the range_start to make sure it doesn't
7055 * go backwards from the start they passed in
7056 */
7057 range_start = max(start, range_start);
7058 found = found_end - range_start;
7059
7060 if (found > 0) {
7061 u64 hole_start = start;
7062 u64 hole_len = len;
7063
7064 em = alloc_extent_map();
7065 if (!em) {
7066 err = -ENOMEM;
7067 goto out;
7068 }
7069 /*
7070 * when btrfs_get_extent can't find anything it
7071 * returns one huge hole
7072 *
7073 * make sure what it found really fits our range, and
7074 * adjust to make sure it is based on the start from
7075 * the caller
7076 */
7077 if (hole_em) {
7078 u64 calc_end = extent_map_end(hole_em);
7079
7080 if (calc_end <= start || (hole_em->start > end)) {
7081 free_extent_map(hole_em);
7082 hole_em = NULL;
7083 } else {
7084 hole_start = max(hole_em->start, start);
7085 hole_len = calc_end - hole_start;
7086 }
7087 }
7088 em->bdev = NULL;
7089 if (hole_em && range_start > hole_start) {
7090 /* our hole starts before our delalloc, so we
7091 * have to return just the parts of the hole
7092 * that go until the delalloc starts
7093 */
7094 em->len = min(hole_len,
7095 range_start - hole_start);
7096 em->start = hole_start;
7097 em->orig_start = hole_start;
7098 /*
7099 * don't adjust block start at all,
7100 * it is fixed at EXTENT_MAP_HOLE
7101 */
7102 em->block_start = hole_em->block_start;
7103 em->block_len = hole_len;
7104 if (test_bit(EXTENT_FLAG_PREALLOC, &hole_em->flags))
7105 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
7106 } else {
7107 em->start = range_start;
7108 em->len = found;
7109 em->orig_start = range_start;
7110 em->block_start = EXTENT_MAP_DELALLOC;
7111 em->block_len = found;
7112 }
7113 } else {
7114 return hole_em;
7115 }
7116 out:
7117
7118 free_extent_map(hole_em);
7119 if (err) {
7120 free_extent_map(em);
7121 return ERR_PTR(err);
7122 }
7123 return em;
7124 }
7125
7126 static struct extent_map *btrfs_create_dio_extent(struct inode *inode,
7127 const u64 start,
7128 const u64 len,
7129 const u64 orig_start,
7130 const u64 block_start,
7131 const u64 block_len,
7132 const u64 orig_block_len,
7133 const u64 ram_bytes,
7134 const int type)
7135 {
7136 struct extent_map *em = NULL;
7137 int ret;
7138
7139 if (type != BTRFS_ORDERED_NOCOW) {
7140 em = create_io_em(inode, start, len, orig_start,
7141 block_start, block_len, orig_block_len,
7142 ram_bytes,
7143 BTRFS_COMPRESS_NONE, /* compress_type */
7144 type);
7145 if (IS_ERR(em))
7146 goto out;
7147 }
7148 ret = btrfs_add_ordered_extent_dio(inode, start, block_start,
7149 len, block_len, type);
7150 if (ret) {
7151 if (em) {
7152 free_extent_map(em);
7153 btrfs_drop_extent_cache(BTRFS_I(inode), start,
7154 start + len - 1, 0);
7155 }
7156 em = ERR_PTR(ret);
7157 }
7158 out:
7159
7160 return em;
7161 }
7162
7163 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
7164 u64 start, u64 len)
7165 {
7166 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7167 struct btrfs_root *root = BTRFS_I(inode)->root;
7168 struct extent_map *em;
7169 struct btrfs_key ins;
7170 u64 alloc_hint;
7171 int ret;
7172
7173 alloc_hint = get_extent_allocation_hint(inode, start, len);
7174 ret = btrfs_reserve_extent(root, len, len, fs_info->sectorsize,
7175 0, alloc_hint, &ins, 1, 1);
7176 if (ret)
7177 return ERR_PTR(ret);
7178
7179 em = btrfs_create_dio_extent(inode, start, ins.offset, start,
7180 ins.objectid, ins.offset, ins.offset,
7181 ins.offset, BTRFS_ORDERED_REGULAR);
7182 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
7183 if (IS_ERR(em))
7184 btrfs_free_reserved_extent(fs_info, ins.objectid,
7185 ins.offset, 1);
7186
7187 return em;
7188 }
7189
7190 /*
7191 * returns 1 when the nocow is safe, < 1 on error, 0 if the
7192 * block must be cow'd
7193 */
7194 noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
7195 u64 *orig_start, u64 *orig_block_len,
7196 u64 *ram_bytes)
7197 {
7198 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7199 struct btrfs_path *path;
7200 int ret;
7201 struct extent_buffer *leaf;
7202 struct btrfs_root *root = BTRFS_I(inode)->root;
7203 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
7204 struct btrfs_file_extent_item *fi;
7205 struct btrfs_key key;
7206 u64 disk_bytenr;
7207 u64 backref_offset;
7208 u64 extent_end;
7209 u64 num_bytes;
7210 int slot;
7211 int found_type;
7212 bool nocow = (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW);
7213
7214 path = btrfs_alloc_path();
7215 if (!path)
7216 return -ENOMEM;
7217
7218 ret = btrfs_lookup_file_extent(NULL, root, path,
7219 btrfs_ino(BTRFS_I(inode)), offset, 0);
7220 if (ret < 0)
7221 goto out;
7222
7223 slot = path->slots[0];
7224 if (ret == 1) {
7225 if (slot == 0) {
7226 /* can't find the item, must cow */
7227 ret = 0;
7228 goto out;
7229 }
7230 slot--;
7231 }
7232 ret = 0;
7233 leaf = path->nodes[0];
7234 btrfs_item_key_to_cpu(leaf, &key, slot);
7235 if (key.objectid != btrfs_ino(BTRFS_I(inode)) ||
7236 key.type != BTRFS_EXTENT_DATA_KEY) {
7237 /* not our file or wrong item type, must cow */
7238 goto out;
7239 }
7240
7241 if (key.offset > offset) {
7242 /* Wrong offset, must cow */
7243 goto out;
7244 }
7245
7246 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
7247 found_type = btrfs_file_extent_type(leaf, fi);
7248 if (found_type != BTRFS_FILE_EXTENT_REG &&
7249 found_type != BTRFS_FILE_EXTENT_PREALLOC) {
7250 /* not a regular extent, must cow */
7251 goto out;
7252 }
7253
7254 if (!nocow && found_type == BTRFS_FILE_EXTENT_REG)
7255 goto out;
7256
7257 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
7258 if (extent_end <= offset)
7259 goto out;
7260
7261 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
7262 if (disk_bytenr == 0)
7263 goto out;
7264
7265 if (btrfs_file_extent_compression(leaf, fi) ||
7266 btrfs_file_extent_encryption(leaf, fi) ||
7267 btrfs_file_extent_other_encoding(leaf, fi))
7268 goto out;
7269
7270 /*
7271 * Do the same check as in btrfs_cross_ref_exist but without the
7272 * unnecessary search.
7273 */
7274 if (btrfs_file_extent_generation(leaf, fi) <=
7275 btrfs_root_last_snapshot(&root->root_item))
7276 goto out;
7277
7278 backref_offset = btrfs_file_extent_offset(leaf, fi);
7279
7280 if (orig_start) {
7281 *orig_start = key.offset - backref_offset;
7282 *orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi);
7283 *ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
7284 }
7285
7286 if (btrfs_extent_readonly(fs_info, disk_bytenr))
7287 goto out;
7288
7289 num_bytes = min(offset + *len, extent_end) - offset;
7290 if (!nocow && found_type == BTRFS_FILE_EXTENT_PREALLOC) {
7291 u64 range_end;
7292
7293 range_end = round_up(offset + num_bytes,
7294 root->fs_info->sectorsize) - 1;
7295 ret = test_range_bit(io_tree, offset, range_end,
7296 EXTENT_DELALLOC, 0, NULL);
7297 if (ret) {
7298 ret = -EAGAIN;
7299 goto out;
7300 }
7301 }
7302
7303 btrfs_release_path(path);
7304
7305 /*
7306 * look for other files referencing this extent, if we
7307 * find any we must cow
7308 */
7309
7310 ret = btrfs_cross_ref_exist(root, btrfs_ino(BTRFS_I(inode)),
7311 key.offset - backref_offset, disk_bytenr);
7312 if (ret) {
7313 ret = 0;
7314 goto out;
7315 }
7316
7317 /*
7318 * adjust disk_bytenr and num_bytes to cover just the bytes
7319 * in this extent we are about to write. If there
7320 * are any csums in that range we have to cow in order
7321 * to keep the csums correct
7322 */
7323 disk_bytenr += backref_offset;
7324 disk_bytenr += offset - key.offset;
7325 if (csum_exist_in_range(fs_info, disk_bytenr, num_bytes))
7326 goto out;
7327 /*
7328 * all of the above have passed, it is safe to overwrite this extent
7329 * without cow
7330 */
7331 *len = num_bytes;
7332 ret = 1;
7333 out:
7334 btrfs_free_path(path);
7335 return ret;
7336 }
7337
7338 static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
7339 struct extent_state **cached_state, int writing)
7340 {
7341 struct btrfs_ordered_extent *ordered;
7342 int ret = 0;
7343
7344 while (1) {
7345 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
7346 cached_state);
7347 /*
7348 * We're concerned with the entire range that we're going to be
7349 * doing DIO to, so we need to make sure there's no ordered
7350 * extents in this range.
7351 */
7352 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), lockstart,
7353 lockend - lockstart + 1);
7354
7355 /*
7356 * We need to make sure there are no buffered pages in this
7357 * range either, we could have raced between the invalidate in
7358 * generic_file_direct_write and locking the extent. The
7359 * invalidate needs to happen so that reads after a write do not
7360 * get stale data.
7361 */
7362 if (!ordered &&
7363 (!writing || !filemap_range_has_page(inode->i_mapping,
7364 lockstart, lockend)))
7365 break;
7366
7367 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
7368 cached_state);
7369
7370 if (ordered) {
7371 /*
7372 * If we are doing a DIO read and the ordered extent we
7373 * found is for a buffered write, we can not wait for it
7374 * to complete and retry, because if we do so we can
7375 * deadlock with concurrent buffered writes on page
7376 * locks. This happens only if our DIO read covers more
7377 * than one extent map, if at this point has already
7378 * created an ordered extent for a previous extent map
7379 * and locked its range in the inode's io tree, and a
7380 * concurrent write against that previous extent map's
7381 * range and this range started (we unlock the ranges
7382 * in the io tree only when the bios complete and
7383 * buffered writes always lock pages before attempting
7384 * to lock range in the io tree).
7385 */
7386 if (writing ||
7387 test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags))
7388 btrfs_start_ordered_extent(inode, ordered, 1);
7389 else
7390 ret = -ENOTBLK;
7391 btrfs_put_ordered_extent(ordered);
7392 } else {
7393 /*
7394 * We could trigger writeback for this range (and wait
7395 * for it to complete) and then invalidate the pages for
7396 * this range (through invalidate_inode_pages2_range()),
7397 * but that can lead us to a deadlock with a concurrent
7398 * call to readpages() (a buffered read or a defrag call
7399 * triggered a readahead) on a page lock due to an
7400 * ordered dio extent we created before but did not have
7401 * yet a corresponding bio submitted (whence it can not
7402 * complete), which makes readpages() wait for that
7403 * ordered extent to complete while holding a lock on
7404 * that page.
7405 */
7406 ret = -ENOTBLK;
7407 }
7408
7409 if (ret)
7410 break;
7411
7412 cond_resched();
7413 }
7414
7415 return ret;
7416 }
7417
7418 /* The callers of this must take lock_extent() */
7419 static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len,
7420 u64 orig_start, u64 block_start,
7421 u64 block_len, u64 orig_block_len,
7422 u64 ram_bytes, int compress_type,
7423 int type)
7424 {
7425 struct extent_map_tree *em_tree;
7426 struct extent_map *em;
7427 struct btrfs_root *root = BTRFS_I(inode)->root;
7428 int ret;
7429
7430 ASSERT(type == BTRFS_ORDERED_PREALLOC ||
7431 type == BTRFS_ORDERED_COMPRESSED ||
7432 type == BTRFS_ORDERED_NOCOW ||
7433 type == BTRFS_ORDERED_REGULAR);
7434
7435 em_tree = &BTRFS_I(inode)->extent_tree;
7436 em = alloc_extent_map();
7437 if (!em)
7438 return ERR_PTR(-ENOMEM);
7439
7440 em->start = start;
7441 em->orig_start = orig_start;
7442 em->len = len;
7443 em->block_len = block_len;
7444 em->block_start = block_start;
7445 em->bdev = root->fs_info->fs_devices->latest_bdev;
7446 em->orig_block_len = orig_block_len;
7447 em->ram_bytes = ram_bytes;
7448 em->generation = -1;
7449 set_bit(EXTENT_FLAG_PINNED, &em->flags);
7450 if (type == BTRFS_ORDERED_PREALLOC) {
7451 set_bit(EXTENT_FLAG_FILLING, &em->flags);
7452 } else if (type == BTRFS_ORDERED_COMPRESSED) {
7453 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
7454 em->compress_type = compress_type;
7455 }
7456
7457 do {
7458 btrfs_drop_extent_cache(BTRFS_I(inode), em->start,
7459 em->start + em->len - 1, 0);
7460 write_lock(&em_tree->lock);
7461 ret = add_extent_mapping(em_tree, em, 1);
7462 write_unlock(&em_tree->lock);
7463 /*
7464 * The caller has taken lock_extent(), who could race with us
7465 * to add em?
7466 */
7467 } while (ret == -EEXIST);
7468
7469 if (ret) {
7470 free_extent_map(em);
7471 return ERR_PTR(ret);
7472 }
7473
7474 /* em got 2 refs now, callers needs to do free_extent_map once. */
7475 return em;
7476 }
7477
7478
7479 static int btrfs_get_blocks_direct_read(struct extent_map *em,
7480 struct buffer_head *bh_result,
7481 struct inode *inode,
7482 u64 start, u64 len)
7483 {
7484 if (em->block_start == EXTENT_MAP_HOLE ||
7485 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
7486 return -ENOENT;
7487
7488 len = min(len, em->len - (start - em->start));
7489
7490 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
7491 inode->i_blkbits;
7492 bh_result->b_size = len;
7493 bh_result->b_bdev = em->bdev;
7494 set_buffer_mapped(bh_result);
7495
7496 return 0;
7497 }
7498
7499 static int btrfs_get_blocks_direct_write(struct extent_map **map,
7500 struct buffer_head *bh_result,
7501 struct inode *inode,
7502 struct btrfs_dio_data *dio_data,
7503 u64 start, u64 len)
7504 {
7505 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7506 struct extent_map *em = *map;
7507 int ret = 0;
7508
7509 /*
7510 * We don't allocate a new extent in the following cases
7511 *
7512 * 1) The inode is marked as NODATACOW. In this case we'll just use the
7513 * existing extent.
7514 * 2) The extent is marked as PREALLOC. We're good to go here and can
7515 * just use the extent.
7516 *
7517 */
7518 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
7519 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
7520 em->block_start != EXTENT_MAP_HOLE)) {
7521 int type;
7522 u64 block_start, orig_start, orig_block_len, ram_bytes;
7523
7524 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
7525 type = BTRFS_ORDERED_PREALLOC;
7526 else
7527 type = BTRFS_ORDERED_NOCOW;
7528 len = min(len, em->len - (start - em->start));
7529 block_start = em->block_start + (start - em->start);
7530
7531 if (can_nocow_extent(inode, start, &len, &orig_start,
7532 &orig_block_len, &ram_bytes) == 1 &&
7533 btrfs_inc_nocow_writers(fs_info, block_start)) {
7534 struct extent_map *em2;
7535
7536 em2 = btrfs_create_dio_extent(inode, start, len,
7537 orig_start, block_start,
7538 len, orig_block_len,
7539 ram_bytes, type);
7540 btrfs_dec_nocow_writers(fs_info, block_start);
7541 if (type == BTRFS_ORDERED_PREALLOC) {
7542 free_extent_map(em);
7543 *map = em = em2;
7544 }
7545
7546 if (em2 && IS_ERR(em2)) {
7547 ret = PTR_ERR(em2);
7548 goto out;
7549 }
7550 /*
7551 * For inode marked NODATACOW or extent marked PREALLOC,
7552 * use the existing or preallocated extent, so does not
7553 * need to adjust btrfs_space_info's bytes_may_use.
7554 */
7555 btrfs_free_reserved_data_space_noquota(inode, start,
7556 len);
7557 goto skip_cow;
7558 }
7559 }
7560
7561 /* this will cow the extent */
7562 len = bh_result->b_size;
7563 free_extent_map(em);
7564 *map = em = btrfs_new_extent_direct(inode, start, len);
7565 if (IS_ERR(em)) {
7566 ret = PTR_ERR(em);
7567 goto out;
7568 }
7569
7570 len = min(len, em->len - (start - em->start));
7571
7572 skip_cow:
7573 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
7574 inode->i_blkbits;
7575 bh_result->b_size = len;
7576 bh_result->b_bdev = em->bdev;
7577 set_buffer_mapped(bh_result);
7578
7579 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
7580 set_buffer_new(bh_result);
7581
7582 /*
7583 * Need to update the i_size under the extent lock so buffered
7584 * readers will get the updated i_size when we unlock.
7585 */
7586 if (!dio_data->overwrite && start + len > i_size_read(inode))
7587 i_size_write(inode, start + len);
7588
7589 WARN_ON(dio_data->reserve < len);
7590 dio_data->reserve -= len;
7591 dio_data->unsubmitted_oe_range_end = start + len;
7592 current->journal_info = dio_data;
7593 out:
7594 return ret;
7595 }
7596
7597 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
7598 struct buffer_head *bh_result, int create)
7599 {
7600 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7601 struct extent_map *em;
7602 struct extent_state *cached_state = NULL;
7603 struct btrfs_dio_data *dio_data = NULL;
7604 u64 start = iblock << inode->i_blkbits;
7605 u64 lockstart, lockend;
7606 u64 len = bh_result->b_size;
7607 int unlock_bits = EXTENT_LOCKED;
7608 int ret = 0;
7609
7610 if (create)
7611 unlock_bits |= EXTENT_DIRTY;
7612 else
7613 len = min_t(u64, len, fs_info->sectorsize);
7614
7615 lockstart = start;
7616 lockend = start + len - 1;
7617
7618 if (current->journal_info) {
7619 /*
7620 * Need to pull our outstanding extents and set journal_info to NULL so
7621 * that anything that needs to check if there's a transaction doesn't get
7622 * confused.
7623 */
7624 dio_data = current->journal_info;
7625 current->journal_info = NULL;
7626 }
7627
7628 /*
7629 * If this errors out it's because we couldn't invalidate pagecache for
7630 * this range and we need to fallback to buffered.
7631 */
7632 if (lock_extent_direct(inode, lockstart, lockend, &cached_state,
7633 create)) {
7634 ret = -ENOTBLK;
7635 goto err;
7636 }
7637
7638 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len, 0);
7639 if (IS_ERR(em)) {
7640 ret = PTR_ERR(em);
7641 goto unlock_err;
7642 }
7643
7644 /*
7645 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered
7646 * io. INLINE is special, and we could probably kludge it in here, but
7647 * it's still buffered so for safety lets just fall back to the generic
7648 * buffered path.
7649 *
7650 * For COMPRESSED we _have_ to read the entire extent in so we can
7651 * decompress it, so there will be buffering required no matter what we
7652 * do, so go ahead and fallback to buffered.
7653 *
7654 * We return -ENOTBLK because that's what makes DIO go ahead and go back
7655 * to buffered IO. Don't blame me, this is the price we pay for using
7656 * the generic code.
7657 */
7658 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
7659 em->block_start == EXTENT_MAP_INLINE) {
7660 free_extent_map(em);
7661 ret = -ENOTBLK;
7662 goto unlock_err;
7663 }
7664
7665 if (create) {
7666 ret = btrfs_get_blocks_direct_write(&em, bh_result, inode,
7667 dio_data, start, len);
7668 if (ret < 0)
7669 goto unlock_err;
7670
7671 /* clear and unlock the entire range */
7672 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
7673 unlock_bits, 1, 0, &cached_state);
7674 } else {
7675 ret = btrfs_get_blocks_direct_read(em, bh_result, inode,
7676 start, len);
7677 /* Can be negative only if we read from a hole */
7678 if (ret < 0) {
7679 ret = 0;
7680 free_extent_map(em);
7681 goto unlock_err;
7682 }
7683 /*
7684 * We need to unlock only the end area that we aren't using.
7685 * The rest is going to be unlocked by the endio routine.
7686 */
7687 lockstart = start + bh_result->b_size;
7688 if (lockstart < lockend) {
7689 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
7690 lockend, unlock_bits, 1, 0,
7691 &cached_state);
7692 } else {
7693 free_extent_state(cached_state);
7694 }
7695 }
7696
7697 free_extent_map(em);
7698
7699 return 0;
7700
7701 unlock_err:
7702 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
7703 unlock_bits, 1, 0, &cached_state);
7704 err:
7705 if (dio_data)
7706 current->journal_info = dio_data;
7707 return ret;
7708 }
7709
7710 static inline blk_status_t submit_dio_repair_bio(struct inode *inode,
7711 struct bio *bio,
7712 int mirror_num)
7713 {
7714 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7715 blk_status_t ret;
7716
7717 BUG_ON(bio_op(bio) == REQ_OP_WRITE);
7718
7719 ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DIO_REPAIR);
7720 if (ret)
7721 return ret;
7722
7723 ret = btrfs_map_bio(fs_info, bio, mirror_num, 0);
7724
7725 return ret;
7726 }
7727
7728 static int btrfs_check_dio_repairable(struct inode *inode,
7729 struct bio *failed_bio,
7730 struct io_failure_record *failrec,
7731 int failed_mirror)
7732 {
7733 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7734 int num_copies;
7735
7736 num_copies = btrfs_num_copies(fs_info, failrec->logical, failrec->len);
7737 if (num_copies == 1) {
7738 /*
7739 * we only have a single copy of the data, so don't bother with
7740 * all the retry and error correction code that follows. no
7741 * matter what the error is, it is very likely to persist.
7742 */
7743 btrfs_debug(fs_info,
7744 "Check DIO Repairable: cannot repair, num_copies=%d, next_mirror %d, failed_mirror %d",
7745 num_copies, failrec->this_mirror, failed_mirror);
7746 return 0;
7747 }
7748
7749 failrec->failed_mirror = failed_mirror;
7750 failrec->this_mirror++;
7751 if (failrec->this_mirror == failed_mirror)
7752 failrec->this_mirror++;
7753
7754 if (failrec->this_mirror > num_copies) {
7755 btrfs_debug(fs_info,
7756 "Check DIO Repairable: (fail) num_copies=%d, next_mirror %d, failed_mirror %d",
7757 num_copies, failrec->this_mirror, failed_mirror);
7758 return 0;
7759 }
7760
7761 return 1;
7762 }
7763
7764 static blk_status_t dio_read_error(struct inode *inode, struct bio *failed_bio,
7765 struct page *page, unsigned int pgoff,
7766 u64 start, u64 end, int failed_mirror,
7767 bio_end_io_t *repair_endio, void *repair_arg)
7768 {
7769 struct io_failure_record *failrec;
7770 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
7771 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
7772 struct bio *bio;
7773 int isector;
7774 unsigned int read_mode = 0;
7775 int segs;
7776 int ret;
7777 blk_status_t status;
7778 struct bio_vec bvec;
7779
7780 BUG_ON(bio_op(failed_bio) == REQ_OP_WRITE);
7781
7782 ret = btrfs_get_io_failure_record(inode, start, end, &failrec);
7783 if (ret)
7784 return errno_to_blk_status(ret);
7785
7786 ret = btrfs_check_dio_repairable(inode, failed_bio, failrec,
7787 failed_mirror);
7788 if (!ret) {
7789 free_io_failure(failure_tree, io_tree, failrec);
7790 return BLK_STS_IOERR;
7791 }
7792
7793 segs = bio_segments(failed_bio);
7794 bio_get_first_bvec(failed_bio, &bvec);
7795 if (segs > 1 ||
7796 (bvec.bv_len > btrfs_inode_sectorsize(inode)))
7797 read_mode |= REQ_FAILFAST_DEV;
7798
7799 isector = start - btrfs_io_bio(failed_bio)->logical;
7800 isector >>= inode->i_sb->s_blocksize_bits;
7801 bio = btrfs_create_repair_bio(inode, failed_bio, failrec, page,
7802 pgoff, isector, repair_endio, repair_arg);
7803 bio->bi_opf = REQ_OP_READ | read_mode;
7804
7805 btrfs_debug(BTRFS_I(inode)->root->fs_info,
7806 "repair DIO read error: submitting new dio read[%#x] to this_mirror=%d, in_validation=%d",
7807 read_mode, failrec->this_mirror, failrec->in_validation);
7808
7809 status = submit_dio_repair_bio(inode, bio, failrec->this_mirror);
7810 if (status) {
7811 free_io_failure(failure_tree, io_tree, failrec);
7812 bio_put(bio);
7813 }
7814
7815 return status;
7816 }
7817
7818 struct btrfs_retry_complete {
7819 struct completion done;
7820 struct inode *inode;
7821 u64 start;
7822 int uptodate;
7823 };
7824
7825 static void btrfs_retry_endio_nocsum(struct bio *bio)
7826 {
7827 struct btrfs_retry_complete *done = bio->bi_private;
7828 struct inode *inode = done->inode;
7829 struct bio_vec *bvec;
7830 struct extent_io_tree *io_tree, *failure_tree;
7831 int i;
7832
7833 if (bio->bi_status)
7834 goto end;
7835
7836 ASSERT(bio->bi_vcnt == 1);
7837 io_tree = &BTRFS_I(inode)->io_tree;
7838 failure_tree = &BTRFS_I(inode)->io_failure_tree;
7839 ASSERT(bio_first_bvec_all(bio)->bv_len == btrfs_inode_sectorsize(inode));
7840
7841 done->uptodate = 1;
7842 ASSERT(!bio_flagged(bio, BIO_CLONED));
7843 bio_for_each_segment_all(bvec, bio, i)
7844 clean_io_failure(BTRFS_I(inode)->root->fs_info, failure_tree,
7845 io_tree, done->start, bvec->bv_page,
7846 btrfs_ino(BTRFS_I(inode)), 0);
7847 end:
7848 complete(&done->done);
7849 bio_put(bio);
7850 }
7851
7852 static blk_status_t __btrfs_correct_data_nocsum(struct inode *inode,
7853 struct btrfs_io_bio *io_bio)
7854 {
7855 struct btrfs_fs_info *fs_info;
7856 struct bio_vec bvec;
7857 struct bvec_iter iter;
7858 struct btrfs_retry_complete done;
7859 u64 start;
7860 unsigned int pgoff;
7861 u32 sectorsize;
7862 int nr_sectors;
7863 blk_status_t ret;
7864 blk_status_t err = BLK_STS_OK;
7865
7866 fs_info = BTRFS_I(inode)->root->fs_info;
7867 sectorsize = fs_info->sectorsize;
7868
7869 start = io_bio->logical;
7870 done.inode = inode;
7871 io_bio->bio.bi_iter = io_bio->iter;
7872
7873 bio_for_each_segment(bvec, &io_bio->bio, iter) {
7874 nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec.bv_len);
7875 pgoff = bvec.bv_offset;
7876
7877 next_block_or_try_again:
7878 done.uptodate = 0;
7879 done.start = start;
7880 init_completion(&done.done);
7881
7882 ret = dio_read_error(inode, &io_bio->bio, bvec.bv_page,
7883 pgoff, start, start + sectorsize - 1,
7884 io_bio->mirror_num,
7885 btrfs_retry_endio_nocsum, &done);
7886 if (ret) {
7887 err = ret;
7888 goto next;
7889 }
7890
7891 wait_for_completion_io(&done.done);
7892
7893 if (!done.uptodate) {
7894 /* We might have another mirror, so try again */
7895 goto next_block_or_try_again;
7896 }
7897
7898 next:
7899 start += sectorsize;
7900
7901 nr_sectors--;
7902 if (nr_sectors) {
7903 pgoff += sectorsize;
7904 ASSERT(pgoff < PAGE_SIZE);
7905 goto next_block_or_try_again;
7906 }
7907 }
7908
7909 return err;
7910 }
7911
7912 static void btrfs_retry_endio(struct bio *bio)
7913 {
7914 struct btrfs_retry_complete *done = bio->bi_private;
7915 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio);
7916 struct extent_io_tree *io_tree, *failure_tree;
7917 struct inode *inode = done->inode;
7918 struct bio_vec *bvec;
7919 int uptodate;
7920 int ret;
7921 int i;
7922
7923 if (bio->bi_status)
7924 goto end;
7925
7926 uptodate = 1;
7927
7928 ASSERT(bio->bi_vcnt == 1);
7929 ASSERT(bio_first_bvec_all(bio)->bv_len == btrfs_inode_sectorsize(done->inode));
7930
7931 io_tree = &BTRFS_I(inode)->io_tree;
7932 failure_tree = &BTRFS_I(inode)->io_failure_tree;
7933
7934 ASSERT(!bio_flagged(bio, BIO_CLONED));
7935 bio_for_each_segment_all(bvec, bio, i) {
7936 ret = __readpage_endio_check(inode, io_bio, i, bvec->bv_page,
7937 bvec->bv_offset, done->start,
7938 bvec->bv_len);
7939 if (!ret)
7940 clean_io_failure(BTRFS_I(inode)->root->fs_info,
7941 failure_tree, io_tree, done->start,
7942 bvec->bv_page,
7943 btrfs_ino(BTRFS_I(inode)),
7944 bvec->bv_offset);
7945 else
7946 uptodate = 0;
7947 }
7948
7949 done->uptodate = uptodate;
7950 end:
7951 complete(&done->done);
7952 bio_put(bio);
7953 }
7954
7955 static blk_status_t __btrfs_subio_endio_read(struct inode *inode,
7956 struct btrfs_io_bio *io_bio, blk_status_t err)
7957 {
7958 struct btrfs_fs_info *fs_info;
7959 struct bio_vec bvec;
7960 struct bvec_iter iter;
7961 struct btrfs_retry_complete done;
7962 u64 start;
7963 u64 offset = 0;
7964 u32 sectorsize;
7965 int nr_sectors;
7966 unsigned int pgoff;
7967 int csum_pos;
7968 bool uptodate = (err == 0);
7969 int ret;
7970 blk_status_t status;
7971
7972 fs_info = BTRFS_I(inode)->root->fs_info;
7973 sectorsize = fs_info->sectorsize;
7974
7975 err = BLK_STS_OK;
7976 start = io_bio->logical;
7977 done.inode = inode;
7978 io_bio->bio.bi_iter = io_bio->iter;
7979
7980 bio_for_each_segment(bvec, &io_bio->bio, iter) {
7981 nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec.bv_len);
7982
7983 pgoff = bvec.bv_offset;
7984 next_block:
7985 if (uptodate) {
7986 csum_pos = BTRFS_BYTES_TO_BLKS(fs_info, offset);
7987 ret = __readpage_endio_check(inode, io_bio, csum_pos,
7988 bvec.bv_page, pgoff, start, sectorsize);
7989 if (likely(!ret))
7990 goto next;
7991 }
7992 try_again:
7993 done.uptodate = 0;
7994 done.start = start;
7995 init_completion(&done.done);
7996
7997 status = dio_read_error(inode, &io_bio->bio, bvec.bv_page,
7998 pgoff, start, start + sectorsize - 1,
7999 io_bio->mirror_num, btrfs_retry_endio,
8000 &done);
8001 if (status) {
8002 err = status;
8003 goto next;
8004 }
8005
8006 wait_for_completion_io(&done.done);
8007
8008 if (!done.uptodate) {
8009 /* We might have another mirror, so try again */
8010 goto try_again;
8011 }
8012 next:
8013 offset += sectorsize;
8014 start += sectorsize;
8015
8016 ASSERT(nr_sectors);
8017
8018 nr_sectors--;
8019 if (nr_sectors) {
8020 pgoff += sectorsize;
8021 ASSERT(pgoff < PAGE_SIZE);
8022 goto next_block;
8023 }
8024 }
8025
8026 return err;
8027 }
8028
8029 static blk_status_t btrfs_subio_endio_read(struct inode *inode,
8030 struct btrfs_io_bio *io_bio, blk_status_t err)
8031 {
8032 bool skip_csum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
8033
8034 if (skip_csum) {
8035 if (unlikely(err))
8036 return __btrfs_correct_data_nocsum(inode, io_bio);
8037 else
8038 return BLK_STS_OK;
8039 } else {
8040 return __btrfs_subio_endio_read(inode, io_bio, err);
8041 }
8042 }
8043
8044 static void btrfs_endio_direct_read(struct bio *bio)
8045 {
8046 struct btrfs_dio_private *dip = bio->bi_private;
8047 struct inode *inode = dip->inode;
8048 struct bio *dio_bio;
8049 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio);
8050 blk_status_t err = bio->bi_status;
8051
8052 if (dip->flags & BTRFS_DIO_ORIG_BIO_SUBMITTED)
8053 err = btrfs_subio_endio_read(inode, io_bio, err);
8054
8055 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
8056 dip->logical_offset + dip->bytes - 1);
8057 dio_bio = dip->dio_bio;
8058
8059 kfree(dip);
8060
8061 dio_bio->bi_status = err;
8062 dio_end_io(dio_bio);
8063
8064 if (io_bio->end_io)
8065 io_bio->end_io(io_bio, blk_status_to_errno(err));
8066 bio_put(bio);
8067 }
8068
8069 static void __endio_write_update_ordered(struct inode *inode,
8070 const u64 offset, const u64 bytes,
8071 const bool uptodate)
8072 {
8073 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8074 struct btrfs_ordered_extent *ordered = NULL;
8075 struct btrfs_workqueue *wq;
8076 btrfs_work_func_t func;
8077 u64 ordered_offset = offset;
8078 u64 ordered_bytes = bytes;
8079 u64 last_offset;
8080
8081 if (btrfs_is_free_space_inode(BTRFS_I(inode))) {
8082 wq = fs_info->endio_freespace_worker;
8083 func = btrfs_freespace_write_helper;
8084 } else {
8085 wq = fs_info->endio_write_workers;
8086 func = btrfs_endio_write_helper;
8087 }
8088
8089 while (ordered_offset < offset + bytes) {
8090 last_offset = ordered_offset;
8091 if (btrfs_dec_test_first_ordered_pending(inode, &ordered,
8092 &ordered_offset,
8093 ordered_bytes,
8094 uptodate)) {
8095 btrfs_init_work(&ordered->work, func,
8096 finish_ordered_fn,
8097 NULL, NULL);
8098 btrfs_queue_work(wq, &ordered->work);
8099 }
8100 /*
8101 * If btrfs_dec_test_ordered_pending does not find any ordered
8102 * extent in the range, we can exit.
8103 */
8104 if (ordered_offset == last_offset)
8105 return;
8106 /*
8107 * Our bio might span multiple ordered extents. In this case
8108 * we keep goin until we have accounted the whole dio.
8109 */
8110 if (ordered_offset < offset + bytes) {
8111 ordered_bytes = offset + bytes - ordered_offset;
8112 ordered = NULL;
8113 }
8114 }
8115 }
8116
8117 static void btrfs_endio_direct_write(struct bio *bio)
8118 {
8119 struct btrfs_dio_private *dip = bio->bi_private;
8120 struct bio *dio_bio = dip->dio_bio;
8121
8122 __endio_write_update_ordered(dip->inode, dip->logical_offset,
8123 dip->bytes, !bio->bi_status);
8124
8125 kfree(dip);
8126
8127 dio_bio->bi_status = bio->bi_status;
8128 dio_end_io(dio_bio);
8129 bio_put(bio);
8130 }
8131
8132 static blk_status_t btrfs_submit_bio_start_direct_io(void *private_data,
8133 struct bio *bio, u64 offset)
8134 {
8135 struct inode *inode = private_data;
8136 blk_status_t ret;
8137 ret = btrfs_csum_one_bio(inode, bio, offset, 1);
8138 BUG_ON(ret); /* -ENOMEM */
8139 return 0;
8140 }
8141
8142 static void btrfs_end_dio_bio(struct bio *bio)
8143 {
8144 struct btrfs_dio_private *dip = bio->bi_private;
8145 blk_status_t err = bio->bi_status;
8146
8147 if (err)
8148 btrfs_warn(BTRFS_I(dip->inode)->root->fs_info,
8149 "direct IO failed ino %llu rw %d,%u sector %#Lx len %u err no %d",
8150 btrfs_ino(BTRFS_I(dip->inode)), bio_op(bio),
8151 bio->bi_opf,
8152 (unsigned long long)bio->bi_iter.bi_sector,
8153 bio->bi_iter.bi_size, err);
8154
8155 if (dip->subio_endio)
8156 err = dip->subio_endio(dip->inode, btrfs_io_bio(bio), err);
8157
8158 if (err) {
8159 /*
8160 * We want to perceive the errors flag being set before
8161 * decrementing the reference count. We don't need a barrier
8162 * since atomic operations with a return value are fully
8163 * ordered as per atomic_t.txt
8164 */
8165 dip->errors = 1;
8166 }
8167
8168 /* if there are more bios still pending for this dio, just exit */
8169 if (!atomic_dec_and_test(&dip->pending_bios))
8170 goto out;
8171
8172 if (dip->errors) {
8173 bio_io_error(dip->orig_bio);
8174 } else {
8175 dip->dio_bio->bi_status = BLK_STS_OK;
8176 bio_endio(dip->orig_bio);
8177 }
8178 out:
8179 bio_put(bio);
8180 }
8181
8182 static inline blk_status_t btrfs_lookup_and_bind_dio_csum(struct inode *inode,
8183 struct btrfs_dio_private *dip,
8184 struct bio *bio,
8185 u64 file_offset)
8186 {
8187 struct btrfs_io_bio *io_bio = btrfs_io_bio(bio);
8188 struct btrfs_io_bio *orig_io_bio = btrfs_io_bio(dip->orig_bio);
8189 blk_status_t ret;
8190
8191 /*
8192 * We load all the csum data we need when we submit
8193 * the first bio to reduce the csum tree search and
8194 * contention.
8195 */
8196 if (dip->logical_offset == file_offset) {
8197 ret = btrfs_lookup_bio_sums_dio(inode, dip->orig_bio,
8198 file_offset);
8199 if (ret)
8200 return ret;
8201 }
8202
8203 if (bio == dip->orig_bio)
8204 return 0;
8205
8206 file_offset -= dip->logical_offset;
8207 file_offset >>= inode->i_sb->s_blocksize_bits;
8208 io_bio->csum = (u8 *)(((u32 *)orig_io_bio->csum) + file_offset);
8209
8210 return 0;
8211 }
8212
8213 static inline blk_status_t btrfs_submit_dio_bio(struct bio *bio,
8214 struct inode *inode, u64 file_offset, int async_submit)
8215 {
8216 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8217 struct btrfs_dio_private *dip = bio->bi_private;
8218 bool write = bio_op(bio) == REQ_OP_WRITE;
8219 blk_status_t ret;
8220
8221 /* Check btrfs_submit_bio_hook() for rules about async submit. */
8222 if (async_submit)
8223 async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers);
8224
8225 if (!write) {
8226 ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DATA);
8227 if (ret)
8228 goto err;
8229 }
8230
8231 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
8232 goto map;
8233
8234 if (write && async_submit) {
8235 ret = btrfs_wq_submit_bio(fs_info, bio, 0, 0,
8236 file_offset, inode,
8237 btrfs_submit_bio_start_direct_io);
8238 goto err;
8239 } else if (write) {
8240 /*
8241 * If we aren't doing async submit, calculate the csum of the
8242 * bio now.
8243 */
8244 ret = btrfs_csum_one_bio(inode, bio, file_offset, 1);
8245 if (ret)
8246 goto err;
8247 } else {
8248 ret = btrfs_lookup_and_bind_dio_csum(inode, dip, bio,
8249 file_offset);
8250 if (ret)
8251 goto err;
8252 }
8253 map:
8254 ret = btrfs_map_bio(fs_info, bio, 0, 0);
8255 err:
8256 return ret;
8257 }
8258
8259 static int btrfs_submit_direct_hook(struct btrfs_dio_private *dip)
8260 {
8261 struct inode *inode = dip->inode;
8262 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8263 struct bio *bio;
8264 struct bio *orig_bio = dip->orig_bio;
8265 u64 start_sector = orig_bio->bi_iter.bi_sector;
8266 u64 file_offset = dip->logical_offset;
8267 u64 map_length;
8268 int async_submit = 0;
8269 u64 submit_len;
8270 int clone_offset = 0;
8271 int clone_len;
8272 int ret;
8273 blk_status_t status;
8274
8275 map_length = orig_bio->bi_iter.bi_size;
8276 submit_len = map_length;
8277 ret = btrfs_map_block(fs_info, btrfs_op(orig_bio), start_sector << 9,
8278 &map_length, NULL, 0);
8279 if (ret)
8280 return -EIO;
8281
8282 if (map_length >= submit_len) {
8283 bio = orig_bio;
8284 dip->flags |= BTRFS_DIO_ORIG_BIO_SUBMITTED;
8285 goto submit;
8286 }
8287
8288 /* async crcs make it difficult to collect full stripe writes. */
8289 if (btrfs_data_alloc_profile(fs_info) & BTRFS_BLOCK_GROUP_RAID56_MASK)
8290 async_submit = 0;
8291 else
8292 async_submit = 1;
8293
8294 /* bio split */
8295 ASSERT(map_length <= INT_MAX);
8296 atomic_inc(&dip->pending_bios);
8297 do {
8298 clone_len = min_t(int, submit_len, map_length);
8299
8300 /*
8301 * This will never fail as it's passing GPF_NOFS and
8302 * the allocation is backed by btrfs_bioset.
8303 */
8304 bio = btrfs_bio_clone_partial(orig_bio, clone_offset,
8305 clone_len);
8306 bio->bi_private = dip;
8307 bio->bi_end_io = btrfs_end_dio_bio;
8308 btrfs_io_bio(bio)->logical = file_offset;
8309
8310 ASSERT(submit_len >= clone_len);
8311 submit_len -= clone_len;
8312 if (submit_len == 0)
8313 break;
8314
8315 /*
8316 * Increase the count before we submit the bio so we know
8317 * the end IO handler won't happen before we increase the
8318 * count. Otherwise, the dip might get freed before we're
8319 * done setting it up.
8320 */
8321 atomic_inc(&dip->pending_bios);
8322
8323 status = btrfs_submit_dio_bio(bio, inode, file_offset,
8324 async_submit);
8325 if (status) {
8326 bio_put(bio);
8327 atomic_dec(&dip->pending_bios);
8328 goto out_err;
8329 }
8330
8331 clone_offset += clone_len;
8332 start_sector += clone_len >> 9;
8333 file_offset += clone_len;
8334
8335 map_length = submit_len;
8336 ret = btrfs_map_block(fs_info, btrfs_op(orig_bio),
8337 start_sector << 9, &map_length, NULL, 0);
8338 if (ret)
8339 goto out_err;
8340 } while (submit_len > 0);
8341
8342 submit:
8343 status = btrfs_submit_dio_bio(bio, inode, file_offset, async_submit);
8344 if (!status)
8345 return 0;
8346
8347 bio_put(bio);
8348 out_err:
8349 dip->errors = 1;
8350 /*
8351 * Before atomic variable goto zero, we must make sure dip->errors is
8352 * perceived to be set. This ordering is ensured by the fact that an
8353 * atomic operations with a return value are fully ordered as per
8354 * atomic_t.txt
8355 */
8356 if (atomic_dec_and_test(&dip->pending_bios))
8357 bio_io_error(dip->orig_bio);
8358
8359 /* bio_end_io() will handle error, so we needn't return it */
8360 return 0;
8361 }
8362
8363 static void btrfs_submit_direct(struct bio *dio_bio, struct inode *inode,
8364 loff_t file_offset)
8365 {
8366 struct btrfs_dio_private *dip = NULL;
8367 struct bio *bio = NULL;
8368 struct btrfs_io_bio *io_bio;
8369 bool write = (bio_op(dio_bio) == REQ_OP_WRITE);
8370 int ret = 0;
8371
8372 bio = btrfs_bio_clone(dio_bio);
8373
8374 dip = kzalloc(sizeof(*dip), GFP_NOFS);
8375 if (!dip) {
8376 ret = -ENOMEM;
8377 goto free_ordered;
8378 }
8379
8380 dip->private = dio_bio->bi_private;
8381 dip->inode = inode;
8382 dip->logical_offset = file_offset;
8383 dip->bytes = dio_bio->bi_iter.bi_size;
8384 dip->disk_bytenr = (u64)dio_bio->bi_iter.bi_sector << 9;
8385 bio->bi_private = dip;
8386 dip->orig_bio = bio;
8387 dip->dio_bio = dio_bio;
8388 atomic_set(&dip->pending_bios, 0);
8389 io_bio = btrfs_io_bio(bio);
8390 io_bio->logical = file_offset;
8391
8392 if (write) {
8393 bio->bi_end_io = btrfs_endio_direct_write;
8394 } else {
8395 bio->bi_end_io = btrfs_endio_direct_read;
8396 dip->subio_endio = btrfs_subio_endio_read;
8397 }
8398
8399 /*
8400 * Reset the range for unsubmitted ordered extents (to a 0 length range)
8401 * even if we fail to submit a bio, because in such case we do the
8402 * corresponding error handling below and it must not be done a second
8403 * time by btrfs_direct_IO().
8404 */
8405 if (write) {
8406 struct btrfs_dio_data *dio_data = current->journal_info;
8407
8408 dio_data->unsubmitted_oe_range_end = dip->logical_offset +
8409 dip->bytes;
8410 dio_data->unsubmitted_oe_range_start =
8411 dio_data->unsubmitted_oe_range_end;
8412 }
8413
8414 ret = btrfs_submit_direct_hook(dip);
8415 if (!ret)
8416 return;
8417
8418 if (io_bio->end_io)
8419 io_bio->end_io(io_bio, ret);
8420
8421 free_ordered:
8422 /*
8423 * If we arrived here it means either we failed to submit the dip
8424 * or we either failed to clone the dio_bio or failed to allocate the
8425 * dip. If we cloned the dio_bio and allocated the dip, we can just
8426 * call bio_endio against our io_bio so that we get proper resource
8427 * cleanup if we fail to submit the dip, otherwise, we must do the
8428 * same as btrfs_endio_direct_[write|read] because we can't call these
8429 * callbacks - they require an allocated dip and a clone of dio_bio.
8430 */
8431 if (bio && dip) {
8432 bio_io_error(bio);
8433 /*
8434 * The end io callbacks free our dip, do the final put on bio
8435 * and all the cleanup and final put for dio_bio (through
8436 * dio_end_io()).
8437 */
8438 dip = NULL;
8439 bio = NULL;
8440 } else {
8441 if (write)
8442 __endio_write_update_ordered(inode,
8443 file_offset,
8444 dio_bio->bi_iter.bi_size,
8445 false);
8446 else
8447 unlock_extent(&BTRFS_I(inode)->io_tree, file_offset,
8448 file_offset + dio_bio->bi_iter.bi_size - 1);
8449
8450 dio_bio->bi_status = BLK_STS_IOERR;
8451 /*
8452 * Releases and cleans up our dio_bio, no need to bio_put()
8453 * nor bio_endio()/bio_io_error() against dio_bio.
8454 */
8455 dio_end_io(dio_bio);
8456 }
8457 if (bio)
8458 bio_put(bio);
8459 kfree(dip);
8460 }
8461
8462 static ssize_t check_direct_IO(struct btrfs_fs_info *fs_info,
8463 const struct iov_iter *iter, loff_t offset)
8464 {
8465 int seg;
8466 int i;
8467 unsigned int blocksize_mask = fs_info->sectorsize - 1;
8468 ssize_t retval = -EINVAL;
8469
8470 if (offset & blocksize_mask)
8471 goto out;
8472
8473 if (iov_iter_alignment(iter) & blocksize_mask)
8474 goto out;
8475
8476 /* If this is a write we don't need to check anymore */
8477 if (iov_iter_rw(iter) != READ || !iter_is_iovec(iter))
8478 return 0;
8479 /*
8480 * Check to make sure we don't have duplicate iov_base's in this
8481 * iovec, if so return EINVAL, otherwise we'll get csum errors
8482 * when reading back.
8483 */
8484 for (seg = 0; seg < iter->nr_segs; seg++) {
8485 for (i = seg + 1; i < iter->nr_segs; i++) {
8486 if (iter->iov[seg].iov_base == iter->iov[i].iov_base)
8487 goto out;
8488 }
8489 }
8490 retval = 0;
8491 out:
8492 return retval;
8493 }
8494
8495 static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
8496 {
8497 struct file *file = iocb->ki_filp;
8498 struct inode *inode = file->f_mapping->host;
8499 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8500 struct btrfs_dio_data dio_data = { 0 };
8501 struct extent_changeset *data_reserved = NULL;
8502 loff_t offset = iocb->ki_pos;
8503 size_t count = 0;
8504 int flags = 0;
8505 bool wakeup = true;
8506 bool relock = false;
8507 ssize_t ret;
8508
8509 if (check_direct_IO(fs_info, iter, offset))
8510 return 0;
8511
8512 inode_dio_begin(inode);
8513
8514 /*
8515 * The generic stuff only does filemap_write_and_wait_range, which
8516 * isn't enough if we've written compressed pages to this area, so
8517 * we need to flush the dirty pages again to make absolutely sure
8518 * that any outstanding dirty pages are on disk.
8519 */
8520 count = iov_iter_count(iter);
8521 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
8522 &BTRFS_I(inode)->runtime_flags))
8523 filemap_fdatawrite_range(inode->i_mapping, offset,
8524 offset + count - 1);
8525
8526 if (iov_iter_rw(iter) == WRITE) {
8527 /*
8528 * If the write DIO is beyond the EOF, we need update
8529 * the isize, but it is protected by i_mutex. So we can
8530 * not unlock the i_mutex at this case.
8531 */
8532 if (offset + count <= inode->i_size) {
8533 dio_data.overwrite = 1;
8534 inode_unlock(inode);
8535 relock = true;
8536 } else if (iocb->ki_flags & IOCB_NOWAIT) {
8537 ret = -EAGAIN;
8538 goto out;
8539 }
8540 ret = btrfs_delalloc_reserve_space(inode, &data_reserved,
8541 offset, count);
8542 if (ret)
8543 goto out;
8544
8545 /*
8546 * We need to know how many extents we reserved so that we can
8547 * do the accounting properly if we go over the number we
8548 * originally calculated. Abuse current->journal_info for this.
8549 */
8550 dio_data.reserve = round_up(count,
8551 fs_info->sectorsize);
8552 dio_data.unsubmitted_oe_range_start = (u64)offset;
8553 dio_data.unsubmitted_oe_range_end = (u64)offset;
8554 current->journal_info = &dio_data;
8555 down_read(&BTRFS_I(inode)->dio_sem);
8556 } else if (test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
8557 &BTRFS_I(inode)->runtime_flags)) {
8558 inode_dio_end(inode);
8559 flags = DIO_LOCKING | DIO_SKIP_HOLES;
8560 wakeup = false;
8561 }
8562
8563 ret = __blockdev_direct_IO(iocb, inode,
8564 fs_info->fs_devices->latest_bdev,
8565 iter, btrfs_get_blocks_direct, NULL,
8566 btrfs_submit_direct, flags);
8567 if (iov_iter_rw(iter) == WRITE) {
8568 up_read(&BTRFS_I(inode)->dio_sem);
8569 current->journal_info = NULL;
8570 if (ret < 0 && ret != -EIOCBQUEUED) {
8571 if (dio_data.reserve)
8572 btrfs_delalloc_release_space(inode, data_reserved,
8573 offset, dio_data.reserve, true);
8574 /*
8575 * On error we might have left some ordered extents
8576 * without submitting corresponding bios for them, so
8577 * cleanup them up to avoid other tasks getting them
8578 * and waiting for them to complete forever.
8579 */
8580 if (dio_data.unsubmitted_oe_range_start <
8581 dio_data.unsubmitted_oe_range_end)
8582 __endio_write_update_ordered(inode,
8583 dio_data.unsubmitted_oe_range_start,
8584 dio_data.unsubmitted_oe_range_end -
8585 dio_data.unsubmitted_oe_range_start,
8586 false);
8587 } else if (ret >= 0 && (size_t)ret < count)
8588 btrfs_delalloc_release_space(inode, data_reserved,
8589 offset, count - (size_t)ret, true);
8590 btrfs_delalloc_release_extents(BTRFS_I(inode), count, false);
8591 }
8592 out:
8593 if (wakeup)
8594 inode_dio_end(inode);
8595 if (relock)
8596 inode_lock(inode);
8597
8598 extent_changeset_free(data_reserved);
8599 return ret;
8600 }
8601
8602 #define BTRFS_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC)
8603
8604 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
8605 __u64 start, __u64 len)
8606 {
8607 int ret;
8608
8609 ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS);
8610 if (ret)
8611 return ret;
8612
8613 return extent_fiemap(inode, fieinfo, start, len);
8614 }
8615
8616 int btrfs_readpage(struct file *file, struct page *page)
8617 {
8618 struct extent_io_tree *tree;
8619 tree = &BTRFS_I(page->mapping->host)->io_tree;
8620 return extent_read_full_page(tree, page, btrfs_get_extent, 0);
8621 }
8622
8623 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
8624 {
8625 struct inode *inode = page->mapping->host;
8626 int ret;
8627
8628 if (current->flags & PF_MEMALLOC) {
8629 redirty_page_for_writepage(wbc, page);
8630 unlock_page(page);
8631 return 0;
8632 }
8633
8634 /*
8635 * If we are under memory pressure we will call this directly from the
8636 * VM, we need to make sure we have the inode referenced for the ordered
8637 * extent. If not just return like we didn't do anything.
8638 */
8639 if (!igrab(inode)) {
8640 redirty_page_for_writepage(wbc, page);
8641 return AOP_WRITEPAGE_ACTIVATE;
8642 }
8643 ret = extent_write_full_page(page, wbc);
8644 btrfs_add_delayed_iput(inode);
8645 return ret;
8646 }
8647
8648 static int btrfs_writepages(struct address_space *mapping,
8649 struct writeback_control *wbc)
8650 {
8651 return extent_writepages(mapping, wbc);
8652 }
8653
8654 static int
8655 btrfs_readpages(struct file *file, struct address_space *mapping,
8656 struct list_head *pages, unsigned nr_pages)
8657 {
8658 return extent_readpages(mapping, pages, nr_pages);
8659 }
8660
8661 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
8662 {
8663 int ret = try_release_extent_mapping(page, gfp_flags);
8664 if (ret == 1) {
8665 ClearPagePrivate(page);
8666 set_page_private(page, 0);
8667 put_page(page);
8668 }
8669 return ret;
8670 }
8671
8672 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
8673 {
8674 if (PageWriteback(page) || PageDirty(page))
8675 return 0;
8676 return __btrfs_releasepage(page, gfp_flags);
8677 }
8678
8679 static void btrfs_invalidatepage(struct page *page, unsigned int offset,
8680 unsigned int length)
8681 {
8682 struct inode *inode = page->mapping->host;
8683 struct extent_io_tree *tree;
8684 struct btrfs_ordered_extent *ordered;
8685 struct extent_state *cached_state = NULL;
8686 u64 page_start = page_offset(page);
8687 u64 page_end = page_start + PAGE_SIZE - 1;
8688 u64 start;
8689 u64 end;
8690 int inode_evicting = inode->i_state & I_FREEING;
8691
8692 /*
8693 * we have the page locked, so new writeback can't start,
8694 * and the dirty bit won't be cleared while we are here.
8695 *
8696 * Wait for IO on this page so that we can safely clear
8697 * the PagePrivate2 bit and do ordered accounting
8698 */
8699 wait_on_page_writeback(page);
8700
8701 tree = &BTRFS_I(inode)->io_tree;
8702 if (offset) {
8703 btrfs_releasepage(page, GFP_NOFS);
8704 return;
8705 }
8706
8707 if (!inode_evicting)
8708 lock_extent_bits(tree, page_start, page_end, &cached_state);
8709 again:
8710 start = page_start;
8711 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), start,
8712 page_end - start + 1);
8713 if (ordered) {
8714 end = min(page_end, ordered->file_offset + ordered->len - 1);
8715 /*
8716 * IO on this page will never be started, so we need
8717 * to account for any ordered extents now
8718 */
8719 if (!inode_evicting)
8720 clear_extent_bit(tree, start, end,
8721 EXTENT_DIRTY | EXTENT_DELALLOC |
8722 EXTENT_DELALLOC_NEW |
8723 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING |
8724 EXTENT_DEFRAG, 1, 0, &cached_state);
8725 /*
8726 * whoever cleared the private bit is responsible
8727 * for the finish_ordered_io
8728 */
8729 if (TestClearPagePrivate2(page)) {
8730 struct btrfs_ordered_inode_tree *tree;
8731 u64 new_len;
8732
8733 tree = &BTRFS_I(inode)->ordered_tree;
8734
8735 spin_lock_irq(&tree->lock);
8736 set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags);
8737 new_len = start - ordered->file_offset;
8738 if (new_len < ordered->truncated_len)
8739 ordered->truncated_len = new_len;
8740 spin_unlock_irq(&tree->lock);
8741
8742 if (btrfs_dec_test_ordered_pending(inode, &ordered,
8743 start,
8744 end - start + 1, 1))
8745 btrfs_finish_ordered_io(ordered);
8746 }
8747 btrfs_put_ordered_extent(ordered);
8748 if (!inode_evicting) {
8749 cached_state = NULL;
8750 lock_extent_bits(tree, start, end,
8751 &cached_state);
8752 }
8753
8754 start = end + 1;
8755 if (start < page_end)
8756 goto again;
8757 }
8758
8759 /*
8760 * Qgroup reserved space handler
8761 * Page here will be either
8762 * 1) Already written to disk
8763 * In this case, its reserved space is released from data rsv map
8764 * and will be freed by delayed_ref handler finally.
8765 * So even we call qgroup_free_data(), it won't decrease reserved
8766 * space.
8767 * 2) Not written to disk
8768 * This means the reserved space should be freed here. However,
8769 * if a truncate invalidates the page (by clearing PageDirty)
8770 * and the page is accounted for while allocating extent
8771 * in btrfs_check_data_free_space() we let delayed_ref to
8772 * free the entire extent.
8773 */
8774 if (PageDirty(page))
8775 btrfs_qgroup_free_data(inode, NULL, page_start, PAGE_SIZE);
8776 if (!inode_evicting) {
8777 clear_extent_bit(tree, page_start, page_end,
8778 EXTENT_LOCKED | EXTENT_DIRTY |
8779 EXTENT_DELALLOC | EXTENT_DELALLOC_NEW |
8780 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 1, 1,
8781 &cached_state);
8782
8783 __btrfs_releasepage(page, GFP_NOFS);
8784 }
8785
8786 ClearPageChecked(page);
8787 if (PagePrivate(page)) {
8788 ClearPagePrivate(page);
8789 set_page_private(page, 0);
8790 put_page(page);
8791 }
8792 }
8793
8794 /*
8795 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
8796 * called from a page fault handler when a page is first dirtied. Hence we must
8797 * be careful to check for EOF conditions here. We set the page up correctly
8798 * for a written page which means we get ENOSPC checking when writing into
8799 * holes and correct delalloc and unwritten extent mapping on filesystems that
8800 * support these features.
8801 *
8802 * We are not allowed to take the i_mutex here so we have to play games to
8803 * protect against truncate races as the page could now be beyond EOF. Because
8804 * truncate_setsize() writes the inode size before removing pages, once we have
8805 * the page lock we can determine safely if the page is beyond EOF. If it is not
8806 * beyond EOF, then the page is guaranteed safe against truncation until we
8807 * unlock the page.
8808 */
8809 vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf)
8810 {
8811 struct page *page = vmf->page;
8812 struct inode *inode = file_inode(vmf->vma->vm_file);
8813 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8814 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
8815 struct btrfs_ordered_extent *ordered;
8816 struct extent_state *cached_state = NULL;
8817 struct extent_changeset *data_reserved = NULL;
8818 char *kaddr;
8819 unsigned long zero_start;
8820 loff_t size;
8821 vm_fault_t ret;
8822 int ret2;
8823 int reserved = 0;
8824 u64 reserved_space;
8825 u64 page_start;
8826 u64 page_end;
8827 u64 end;
8828
8829 reserved_space = PAGE_SIZE;
8830
8831 sb_start_pagefault(inode->i_sb);
8832 page_start = page_offset(page);
8833 page_end = page_start + PAGE_SIZE - 1;
8834 end = page_end;
8835
8836 /*
8837 * Reserving delalloc space after obtaining the page lock can lead to
8838 * deadlock. For example, if a dirty page is locked by this function
8839 * and the call to btrfs_delalloc_reserve_space() ends up triggering
8840 * dirty page write out, then the btrfs_writepage() function could
8841 * end up waiting indefinitely to get a lock on the page currently
8842 * being processed by btrfs_page_mkwrite() function.
8843 */
8844 ret2 = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start,
8845 reserved_space);
8846 if (!ret2) {
8847 ret2 = file_update_time(vmf->vma->vm_file);
8848 reserved = 1;
8849 }
8850 if (ret2) {
8851 ret = vmf_error(ret2);
8852 if (reserved)
8853 goto out;
8854 goto out_noreserve;
8855 }
8856
8857 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
8858 again:
8859 lock_page(page);
8860 size = i_size_read(inode);
8861
8862 if ((page->mapping != inode->i_mapping) ||
8863 (page_start >= size)) {
8864 /* page got truncated out from underneath us */
8865 goto out_unlock;
8866 }
8867 wait_on_page_writeback(page);
8868
8869 lock_extent_bits(io_tree, page_start, page_end, &cached_state);
8870 set_page_extent_mapped(page);
8871
8872 /*
8873 * we can't set the delalloc bits if there are pending ordered
8874 * extents. Drop our locks and wait for them to finish
8875 */
8876 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), page_start,
8877 PAGE_SIZE);
8878 if (ordered) {
8879 unlock_extent_cached(io_tree, page_start, page_end,
8880 &cached_state);
8881 unlock_page(page);
8882 btrfs_start_ordered_extent(inode, ordered, 1);
8883 btrfs_put_ordered_extent(ordered);
8884 goto again;
8885 }
8886
8887 if (page->index == ((size - 1) >> PAGE_SHIFT)) {
8888 reserved_space = round_up(size - page_start,
8889 fs_info->sectorsize);
8890 if (reserved_space < PAGE_SIZE) {
8891 end = page_start + reserved_space - 1;
8892 btrfs_delalloc_release_space(inode, data_reserved,
8893 page_start, PAGE_SIZE - reserved_space,
8894 true);
8895 }
8896 }
8897
8898 /*
8899 * page_mkwrite gets called when the page is firstly dirtied after it's
8900 * faulted in, but write(2) could also dirty a page and set delalloc
8901 * bits, thus in this case for space account reason, we still need to
8902 * clear any delalloc bits within this page range since we have to
8903 * reserve data&meta space before lock_page() (see above comments).
8904 */
8905 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, end,
8906 EXTENT_DIRTY | EXTENT_DELALLOC |
8907 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
8908 0, 0, &cached_state);
8909
8910 ret2 = btrfs_set_extent_delalloc(inode, page_start, end, 0,
8911 &cached_state, 0);
8912 if (ret2) {
8913 unlock_extent_cached(io_tree, page_start, page_end,
8914 &cached_state);
8915 ret = VM_FAULT_SIGBUS;
8916 goto out_unlock;
8917 }
8918 ret2 = 0;
8919
8920 /* page is wholly or partially inside EOF */
8921 if (page_start + PAGE_SIZE > size)
8922 zero_start = size & ~PAGE_MASK;
8923 else
8924 zero_start = PAGE_SIZE;
8925
8926 if (zero_start != PAGE_SIZE) {
8927 kaddr = kmap(page);
8928 memset(kaddr + zero_start, 0, PAGE_SIZE - zero_start);
8929 flush_dcache_page(page);
8930 kunmap(page);
8931 }
8932 ClearPageChecked(page);
8933 set_page_dirty(page);
8934 SetPageUptodate(page);
8935
8936 BTRFS_I(inode)->last_trans = fs_info->generation;
8937 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
8938 BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit;
8939
8940 unlock_extent_cached(io_tree, page_start, page_end, &cached_state);
8941
8942 if (!ret2) {
8943 btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, true);
8944 sb_end_pagefault(inode->i_sb);
8945 extent_changeset_free(data_reserved);
8946 return VM_FAULT_LOCKED;
8947 }
8948
8949 out_unlock:
8950 unlock_page(page);
8951 out:
8952 btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE, (ret != 0));
8953 btrfs_delalloc_release_space(inode, data_reserved, page_start,
8954 reserved_space, (ret != 0));
8955 out_noreserve:
8956 sb_end_pagefault(inode->i_sb);
8957 extent_changeset_free(data_reserved);
8958 return ret;
8959 }
8960
8961 static int btrfs_truncate(struct inode *inode, bool skip_writeback)
8962 {
8963 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8964 struct btrfs_root *root = BTRFS_I(inode)->root;
8965 struct btrfs_block_rsv *rsv;
8966 int ret;
8967 struct btrfs_trans_handle *trans;
8968 u64 mask = fs_info->sectorsize - 1;
8969 u64 min_size = btrfs_calc_trunc_metadata_size(fs_info, 1);
8970
8971 if (!skip_writeback) {
8972 ret = btrfs_wait_ordered_range(inode, inode->i_size & (~mask),
8973 (u64)-1);
8974 if (ret)
8975 return ret;
8976 }
8977
8978 /*
8979 * Yes ladies and gentlemen, this is indeed ugly. We have a couple of
8980 * things going on here:
8981 *
8982 * 1) We need to reserve space to update our inode.
8983 *
8984 * 2) We need to have something to cache all the space that is going to
8985 * be free'd up by the truncate operation, but also have some slack
8986 * space reserved in case it uses space during the truncate (thank you
8987 * very much snapshotting).
8988 *
8989 * And we need these to be separate. The fact is we can use a lot of
8990 * space doing the truncate, and we have no earthly idea how much space
8991 * we will use, so we need the truncate reservation to be separate so it
8992 * doesn't end up using space reserved for updating the inode. We also
8993 * need to be able to stop the transaction and start a new one, which
8994 * means we need to be able to update the inode several times, and we
8995 * have no idea of knowing how many times that will be, so we can't just
8996 * reserve 1 item for the entirety of the operation, so that has to be
8997 * done separately as well.
8998 *
8999 * So that leaves us with
9000 *
9001 * 1) rsv - for the truncate reservation, which we will steal from the
9002 * transaction reservation.
9003 * 2) fs_info->trans_block_rsv - this will have 1 items worth left for
9004 * updating the inode.
9005 */
9006 rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP);
9007 if (!rsv)
9008 return -ENOMEM;
9009 rsv->size = min_size;
9010 rsv->failfast = 1;
9011
9012 /*
9013 * 1 for the truncate slack space
9014 * 1 for updating the inode.
9015 */
9016 trans = btrfs_start_transaction(root, 2);
9017 if (IS_ERR(trans)) {
9018 ret = PTR_ERR(trans);
9019 goto out;
9020 }
9021
9022 /* Migrate the slack space for the truncate to our reserve */
9023 ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv, rsv,
9024 min_size, 0);
9025 BUG_ON(ret);
9026
9027 /*
9028 * So if we truncate and then write and fsync we normally would just
9029 * write the extents that changed, which is a problem if we need to
9030 * first truncate that entire inode. So set this flag so we write out
9031 * all of the extents in the inode to the sync log so we're completely
9032 * safe.
9033 */
9034 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
9035 trans->block_rsv = rsv;
9036
9037 while (1) {
9038 ret = btrfs_truncate_inode_items(trans, root, inode,
9039 inode->i_size,
9040 BTRFS_EXTENT_DATA_KEY);
9041 trans->block_rsv = &fs_info->trans_block_rsv;
9042 if (ret != -ENOSPC && ret != -EAGAIN)
9043 break;
9044
9045 ret = btrfs_update_inode(trans, root, inode);
9046 if (ret)
9047 break;
9048
9049 btrfs_end_transaction(trans);
9050 btrfs_btree_balance_dirty(fs_info);
9051
9052 trans = btrfs_start_transaction(root, 2);
9053 if (IS_ERR(trans)) {
9054 ret = PTR_ERR(trans);
9055 trans = NULL;
9056 break;
9057 }
9058
9059 btrfs_block_rsv_release(fs_info, rsv, -1);
9060 ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv,
9061 rsv, min_size, 0);
9062 BUG_ON(ret); /* shouldn't happen */
9063 trans->block_rsv = rsv;
9064 }
9065
9066 /*
9067 * We can't call btrfs_truncate_block inside a trans handle as we could
9068 * deadlock with freeze, if we got NEED_TRUNCATE_BLOCK then we know
9069 * we've truncated everything except the last little bit, and can do
9070 * btrfs_truncate_block and then update the disk_i_size.
9071 */
9072 if (ret == NEED_TRUNCATE_BLOCK) {
9073 btrfs_end_transaction(trans);
9074 btrfs_btree_balance_dirty(fs_info);
9075
9076 ret = btrfs_truncate_block(inode, inode->i_size, 0, 0);
9077 if (ret)
9078 goto out;
9079 trans = btrfs_start_transaction(root, 1);
9080 if (IS_ERR(trans)) {
9081 ret = PTR_ERR(trans);
9082 goto out;
9083 }
9084 btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
9085 }
9086
9087 if (trans) {
9088 int ret2;
9089
9090 trans->block_rsv = &fs_info->trans_block_rsv;
9091 ret2 = btrfs_update_inode(trans, root, inode);
9092 if (ret2 && !ret)
9093 ret = ret2;
9094
9095 ret2 = btrfs_end_transaction(trans);
9096 if (ret2 && !ret)
9097 ret = ret2;
9098 btrfs_btree_balance_dirty(fs_info);
9099 }
9100 out:
9101 btrfs_free_block_rsv(fs_info, rsv);
9102
9103 return ret;
9104 }
9105
9106 /*
9107 * create a new subvolume directory/inode (helper for the ioctl).
9108 */
9109 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
9110 struct btrfs_root *new_root,
9111 struct btrfs_root *parent_root,
9112 u64 new_dirid)
9113 {
9114 struct inode *inode;
9115 int err;
9116 u64 index = 0;
9117
9118 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2,
9119 new_dirid, new_dirid,
9120 S_IFDIR | (~current_umask() & S_IRWXUGO),
9121 &index);
9122 if (IS_ERR(inode))
9123 return PTR_ERR(inode);
9124 inode->i_op = &btrfs_dir_inode_operations;
9125 inode->i_fop = &btrfs_dir_file_operations;
9126
9127 set_nlink(inode, 1);
9128 btrfs_i_size_write(BTRFS_I(inode), 0);
9129 unlock_new_inode(inode);
9130
9131 err = btrfs_subvol_inherit_props(trans, new_root, parent_root);
9132 if (err)
9133 btrfs_err(new_root->fs_info,
9134 "error inheriting subvolume %llu properties: %d",
9135 new_root->root_key.objectid, err);
9136
9137 err = btrfs_update_inode(trans, new_root, inode);
9138
9139 iput(inode);
9140 return err;
9141 }
9142
9143 struct inode *btrfs_alloc_inode(struct super_block *sb)
9144 {
9145 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
9146 struct btrfs_inode *ei;
9147 struct inode *inode;
9148
9149 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_KERNEL);
9150 if (!ei)
9151 return NULL;
9152
9153 ei->root = NULL;
9154 ei->generation = 0;
9155 ei->last_trans = 0;
9156 ei->last_sub_trans = 0;
9157 ei->logged_trans = 0;
9158 ei->delalloc_bytes = 0;
9159 ei->new_delalloc_bytes = 0;
9160 ei->defrag_bytes = 0;
9161 ei->disk_i_size = 0;
9162 ei->flags = 0;
9163 ei->csum_bytes = 0;
9164 ei->index_cnt = (u64)-1;
9165 ei->dir_index = 0;
9166 ei->last_unlink_trans = 0;
9167 ei->last_log_commit = 0;
9168
9169 spin_lock_init(&ei->lock);
9170 ei->outstanding_extents = 0;
9171 if (sb->s_magic != BTRFS_TEST_MAGIC)
9172 btrfs_init_metadata_block_rsv(fs_info, &ei->block_rsv,
9173 BTRFS_BLOCK_RSV_DELALLOC);
9174 ei->runtime_flags = 0;
9175 ei->prop_compress = BTRFS_COMPRESS_NONE;
9176 ei->defrag_compress = BTRFS_COMPRESS_NONE;
9177
9178 ei->delayed_node = NULL;
9179
9180 ei->i_otime.tv_sec = 0;
9181 ei->i_otime.tv_nsec = 0;
9182
9183 inode = &ei->vfs_inode;
9184 extent_map_tree_init(&ei->extent_tree);
9185 extent_io_tree_init(&ei->io_tree, inode);
9186 extent_io_tree_init(&ei->io_failure_tree, inode);
9187 ei->io_tree.track_uptodate = 1;
9188 ei->io_failure_tree.track_uptodate = 1;
9189 atomic_set(&ei->sync_writers, 0);
9190 mutex_init(&ei->log_mutex);
9191 mutex_init(&ei->delalloc_mutex);
9192 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
9193 INIT_LIST_HEAD(&ei->delalloc_inodes);
9194 INIT_LIST_HEAD(&ei->delayed_iput);
9195 RB_CLEAR_NODE(&ei->rb_node);
9196 init_rwsem(&ei->dio_sem);
9197
9198 return inode;
9199 }
9200
9201 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
9202 void btrfs_test_destroy_inode(struct inode *inode)
9203 {
9204 btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0);
9205 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
9206 }
9207 #endif
9208
9209 static void btrfs_i_callback(struct rcu_head *head)
9210 {
9211 struct inode *inode = container_of(head, struct inode, i_rcu);
9212 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
9213 }
9214
9215 void btrfs_destroy_inode(struct inode *inode)
9216 {
9217 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
9218 struct btrfs_ordered_extent *ordered;
9219 struct btrfs_root *root = BTRFS_I(inode)->root;
9220
9221 WARN_ON(!hlist_empty(&inode->i_dentry));
9222 WARN_ON(inode->i_data.nrpages);
9223 WARN_ON(BTRFS_I(inode)->block_rsv.reserved);
9224 WARN_ON(BTRFS_I(inode)->block_rsv.size);
9225 WARN_ON(BTRFS_I(inode)->outstanding_extents);
9226 WARN_ON(BTRFS_I(inode)->delalloc_bytes);
9227 WARN_ON(BTRFS_I(inode)->new_delalloc_bytes);
9228 WARN_ON(BTRFS_I(inode)->csum_bytes);
9229 WARN_ON(BTRFS_I(inode)->defrag_bytes);
9230
9231 /*
9232 * This can happen where we create an inode, but somebody else also
9233 * created the same inode and we need to destroy the one we already
9234 * created.
9235 */
9236 if (!root)
9237 goto free;
9238
9239 while (1) {
9240 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
9241 if (!ordered)
9242 break;
9243 else {
9244 btrfs_err(fs_info,
9245 "found ordered extent %llu %llu on inode cleanup",
9246 ordered->file_offset, ordered->len);
9247 btrfs_remove_ordered_extent(inode, ordered);
9248 btrfs_put_ordered_extent(ordered);
9249 btrfs_put_ordered_extent(ordered);
9250 }
9251 }
9252 btrfs_qgroup_check_reserved_leak(inode);
9253 inode_tree_del(inode);
9254 btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0);
9255 free:
9256 call_rcu(&inode->i_rcu, btrfs_i_callback);
9257 }
9258
9259 int btrfs_drop_inode(struct inode *inode)
9260 {
9261 struct btrfs_root *root = BTRFS_I(inode)->root;
9262
9263 if (root == NULL)
9264 return 1;
9265
9266 /* the snap/subvol tree is on deleting */
9267 if (btrfs_root_refs(&root->root_item) == 0)
9268 return 1;
9269 else
9270 return generic_drop_inode(inode);
9271 }
9272
9273 static void init_once(void *foo)
9274 {
9275 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
9276
9277 inode_init_once(&ei->vfs_inode);
9278 }
9279
9280 void __cold btrfs_destroy_cachep(void)
9281 {
9282 /*
9283 * Make sure all delayed rcu free inodes are flushed before we
9284 * destroy cache.
9285 */
9286 rcu_barrier();
9287 kmem_cache_destroy(btrfs_inode_cachep);
9288 kmem_cache_destroy(btrfs_trans_handle_cachep);
9289 kmem_cache_destroy(btrfs_path_cachep);
9290 kmem_cache_destroy(btrfs_free_space_cachep);
9291 }
9292
9293 int __init btrfs_init_cachep(void)
9294 {
9295 btrfs_inode_cachep = kmem_cache_create("btrfs_inode",
9296 sizeof(struct btrfs_inode), 0,
9297 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD | SLAB_ACCOUNT,
9298 init_once);
9299 if (!btrfs_inode_cachep)
9300 goto fail;
9301
9302 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle",
9303 sizeof(struct btrfs_trans_handle), 0,
9304 SLAB_TEMPORARY | SLAB_MEM_SPREAD, NULL);
9305 if (!btrfs_trans_handle_cachep)
9306 goto fail;
9307
9308 btrfs_path_cachep = kmem_cache_create("btrfs_path",
9309 sizeof(struct btrfs_path), 0,
9310 SLAB_MEM_SPREAD, NULL);
9311 if (!btrfs_path_cachep)
9312 goto fail;
9313
9314 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space",
9315 sizeof(struct btrfs_free_space), 0,
9316 SLAB_MEM_SPREAD, NULL);
9317 if (!btrfs_free_space_cachep)
9318 goto fail;
9319
9320 return 0;
9321 fail:
9322 btrfs_destroy_cachep();
9323 return -ENOMEM;
9324 }
9325
9326 static int btrfs_getattr(const struct path *path, struct kstat *stat,
9327 u32 request_mask, unsigned int flags)
9328 {
9329 u64 delalloc_bytes;
9330 struct inode *inode = d_inode(path->dentry);
9331 u32 blocksize = inode->i_sb->s_blocksize;
9332 u32 bi_flags = BTRFS_I(inode)->flags;
9333
9334 stat->result_mask |= STATX_BTIME;
9335 stat->btime.tv_sec = BTRFS_I(inode)->i_otime.tv_sec;
9336 stat->btime.tv_nsec = BTRFS_I(inode)->i_otime.tv_nsec;
9337 if (bi_flags & BTRFS_INODE_APPEND)
9338 stat->attributes |= STATX_ATTR_APPEND;
9339 if (bi_flags & BTRFS_INODE_COMPRESS)
9340 stat->attributes |= STATX_ATTR_COMPRESSED;
9341 if (bi_flags & BTRFS_INODE_IMMUTABLE)
9342 stat->attributes |= STATX_ATTR_IMMUTABLE;
9343 if (bi_flags & BTRFS_INODE_NODUMP)
9344 stat->attributes |= STATX_ATTR_NODUMP;
9345
9346 stat->attributes_mask |= (STATX_ATTR_APPEND |
9347 STATX_ATTR_COMPRESSED |
9348 STATX_ATTR_IMMUTABLE |
9349 STATX_ATTR_NODUMP);
9350
9351 generic_fillattr(inode, stat);
9352 stat->dev = BTRFS_I(inode)->root->anon_dev;
9353
9354 spin_lock(&BTRFS_I(inode)->lock);
9355 delalloc_bytes = BTRFS_I(inode)->new_delalloc_bytes;
9356 spin_unlock(&BTRFS_I(inode)->lock);
9357 stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) +
9358 ALIGN(delalloc_bytes, blocksize)) >> 9;
9359 return 0;
9360 }
9361
9362 static int btrfs_rename_exchange(struct inode *old_dir,
9363 struct dentry *old_dentry,
9364 struct inode *new_dir,
9365 struct dentry *new_dentry)
9366 {
9367 struct btrfs_fs_info *fs_info = btrfs_sb(old_dir->i_sb);
9368 struct btrfs_trans_handle *trans;
9369 struct btrfs_root *root = BTRFS_I(old_dir)->root;
9370 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
9371 struct inode *new_inode = new_dentry->d_inode;
9372 struct inode *old_inode = old_dentry->d_inode;
9373 struct timespec64 ctime = current_time(old_inode);
9374 struct dentry *parent;
9375 u64 old_ino = btrfs_ino(BTRFS_I(old_inode));
9376 u64 new_ino = btrfs_ino(BTRFS_I(new_inode));
9377 u64 old_idx = 0;
9378 u64 new_idx = 0;
9379 u64 root_objectid;
9380 int ret;
9381 bool root_log_pinned = false;
9382 bool dest_log_pinned = false;
9383 struct btrfs_log_ctx ctx_root;
9384 struct btrfs_log_ctx ctx_dest;
9385 bool sync_log_root = false;
9386 bool sync_log_dest = false;
9387 bool commit_transaction = false;
9388
9389 /* we only allow rename subvolume link between subvolumes */
9390 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
9391 return -EXDEV;
9392
9393 btrfs_init_log_ctx(&ctx_root, old_inode);
9394 btrfs_init_log_ctx(&ctx_dest, new_inode);
9395
9396 /* close the race window with snapshot create/destroy ioctl */
9397 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
9398 down_read(&fs_info->subvol_sem);
9399 if (new_ino == BTRFS_FIRST_FREE_OBJECTID)
9400 down_read(&fs_info->subvol_sem);
9401
9402 /*
9403 * We want to reserve the absolute worst case amount of items. So if
9404 * both inodes are subvols and we need to unlink them then that would
9405 * require 4 item modifications, but if they are both normal inodes it
9406 * would require 5 item modifications, so we'll assume their normal
9407 * inodes. So 5 * 2 is 10, plus 2 for the new links, so 12 total items
9408 * should cover the worst case number of items we'll modify.
9409 */
9410 trans = btrfs_start_transaction(root, 12);
9411 if (IS_ERR(trans)) {
9412 ret = PTR_ERR(trans);
9413 goto out_notrans;
9414 }
9415
9416 /*
9417 * We need to find a free sequence number both in the source and
9418 * in the destination directory for the exchange.
9419 */
9420 ret = btrfs_set_inode_index(BTRFS_I(new_dir), &old_idx);
9421 if (ret)
9422 goto out_fail;
9423 ret = btrfs_set_inode_index(BTRFS_I(old_dir), &new_idx);
9424 if (ret)
9425 goto out_fail;
9426
9427 BTRFS_I(old_inode)->dir_index = 0ULL;
9428 BTRFS_I(new_inode)->dir_index = 0ULL;
9429
9430 /* Reference for the source. */
9431 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) {
9432 /* force full log commit if subvolume involved. */
9433 btrfs_set_log_full_commit(fs_info, trans);
9434 } else {
9435 btrfs_pin_log_trans(root);
9436 root_log_pinned = true;
9437 ret = btrfs_insert_inode_ref(trans, dest,
9438 new_dentry->d_name.name,
9439 new_dentry->d_name.len,
9440 old_ino,
9441 btrfs_ino(BTRFS_I(new_dir)),
9442 old_idx);
9443 if (ret)
9444 goto out_fail;
9445 }
9446
9447 /* And now for the dest. */
9448 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) {
9449 /* force full log commit if subvolume involved. */
9450 btrfs_set_log_full_commit(fs_info, trans);
9451 } else {
9452 btrfs_pin_log_trans(dest);
9453 dest_log_pinned = true;
9454 ret = btrfs_insert_inode_ref(trans, root,
9455 old_dentry->d_name.name,
9456 old_dentry->d_name.len,
9457 new_ino,
9458 btrfs_ino(BTRFS_I(old_dir)),
9459 new_idx);
9460 if (ret)
9461 goto out_fail;
9462 }
9463
9464 /* Update inode version and ctime/mtime. */
9465 inode_inc_iversion(old_dir);
9466 inode_inc_iversion(new_dir);
9467 inode_inc_iversion(old_inode);
9468 inode_inc_iversion(new_inode);
9469 old_dir->i_ctime = old_dir->i_mtime = ctime;
9470 new_dir->i_ctime = new_dir->i_mtime = ctime;
9471 old_inode->i_ctime = ctime;
9472 new_inode->i_ctime = ctime;
9473
9474 if (old_dentry->d_parent != new_dentry->d_parent) {
9475 btrfs_record_unlink_dir(trans, BTRFS_I(old_dir),
9476 BTRFS_I(old_inode), 1);
9477 btrfs_record_unlink_dir(trans, BTRFS_I(new_dir),
9478 BTRFS_I(new_inode), 1);
9479 }
9480
9481 /* src is a subvolume */
9482 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) {
9483 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
9484 ret = btrfs_unlink_subvol(trans, old_dir, root_objectid,
9485 old_dentry->d_name.name,
9486 old_dentry->d_name.len);
9487 } else { /* src is an inode */
9488 ret = __btrfs_unlink_inode(trans, root, BTRFS_I(old_dir),
9489 BTRFS_I(old_dentry->d_inode),
9490 old_dentry->d_name.name,
9491 old_dentry->d_name.len);
9492 if (!ret)
9493 ret = btrfs_update_inode(trans, root, old_inode);
9494 }
9495 if (ret) {
9496 btrfs_abort_transaction(trans, ret);
9497 goto out_fail;
9498 }
9499
9500 /* dest is a subvolume */
9501 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) {
9502 root_objectid = BTRFS_I(new_inode)->root->root_key.objectid;
9503 ret = btrfs_unlink_subvol(trans, new_dir, root_objectid,
9504 new_dentry->d_name.name,
9505 new_dentry->d_name.len);
9506 } else { /* dest is an inode */
9507 ret = __btrfs_unlink_inode(trans, dest, BTRFS_I(new_dir),
9508 BTRFS_I(new_dentry->d_inode),
9509 new_dentry->d_name.name,
9510 new_dentry->d_name.len);
9511 if (!ret)
9512 ret = btrfs_update_inode(trans, dest, new_inode);
9513 }
9514 if (ret) {
9515 btrfs_abort_transaction(trans, ret);
9516 goto out_fail;
9517 }
9518
9519 ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode),
9520 new_dentry->d_name.name,
9521 new_dentry->d_name.len, 0, old_idx);
9522 if (ret) {
9523 btrfs_abort_transaction(trans, ret);
9524 goto out_fail;
9525 }
9526
9527 ret = btrfs_add_link(trans, BTRFS_I(old_dir), BTRFS_I(new_inode),
9528 old_dentry->d_name.name,
9529 old_dentry->d_name.len, 0, new_idx);
9530 if (ret) {
9531 btrfs_abort_transaction(trans, ret);
9532 goto out_fail;
9533 }
9534
9535 if (old_inode->i_nlink == 1)
9536 BTRFS_I(old_inode)->dir_index = old_idx;
9537 if (new_inode->i_nlink == 1)
9538 BTRFS_I(new_inode)->dir_index = new_idx;
9539
9540 if (root_log_pinned) {
9541 parent = new_dentry->d_parent;
9542 ret = btrfs_log_new_name(trans, BTRFS_I(old_inode),
9543 BTRFS_I(old_dir), parent,
9544 false, &ctx_root);
9545 if (ret == BTRFS_NEED_LOG_SYNC)
9546 sync_log_root = true;
9547 else if (ret == BTRFS_NEED_TRANS_COMMIT)
9548 commit_transaction = true;
9549 ret = 0;
9550 btrfs_end_log_trans(root);
9551 root_log_pinned = false;
9552 }
9553 if (dest_log_pinned) {
9554 if (!commit_transaction) {
9555 parent = old_dentry->d_parent;
9556 ret = btrfs_log_new_name(trans, BTRFS_I(new_inode),
9557 BTRFS_I(new_dir), parent,
9558 false, &ctx_dest);
9559 if (ret == BTRFS_NEED_LOG_SYNC)
9560 sync_log_dest = true;
9561 else if (ret == BTRFS_NEED_TRANS_COMMIT)
9562 commit_transaction = true;
9563 ret = 0;
9564 }
9565 btrfs_end_log_trans(dest);
9566 dest_log_pinned = false;
9567 }
9568 out_fail:
9569 /*
9570 * If we have pinned a log and an error happened, we unpin tasks
9571 * trying to sync the log and force them to fallback to a transaction
9572 * commit if the log currently contains any of the inodes involved in
9573 * this rename operation (to ensure we do not persist a log with an
9574 * inconsistent state for any of these inodes or leading to any
9575 * inconsistencies when replayed). If the transaction was aborted, the
9576 * abortion reason is propagated to userspace when attempting to commit
9577 * the transaction. If the log does not contain any of these inodes, we
9578 * allow the tasks to sync it.
9579 */
9580 if (ret && (root_log_pinned || dest_log_pinned)) {
9581 if (btrfs_inode_in_log(BTRFS_I(old_dir), fs_info->generation) ||
9582 btrfs_inode_in_log(BTRFS_I(new_dir), fs_info->generation) ||
9583 btrfs_inode_in_log(BTRFS_I(old_inode), fs_info->generation) ||
9584 (new_inode &&
9585 btrfs_inode_in_log(BTRFS_I(new_inode), fs_info->generation)))
9586 btrfs_set_log_full_commit(fs_info, trans);
9587
9588 if (root_log_pinned) {
9589 btrfs_end_log_trans(root);
9590 root_log_pinned = false;
9591 }
9592 if (dest_log_pinned) {
9593 btrfs_end_log_trans(dest);
9594 dest_log_pinned = false;
9595 }
9596 }
9597 if (!ret && sync_log_root && !commit_transaction) {
9598 ret = btrfs_sync_log(trans, BTRFS_I(old_inode)->root,
9599 &ctx_root);
9600 if (ret)
9601 commit_transaction = true;
9602 }
9603 if (!ret && sync_log_dest && !commit_transaction) {
9604 ret = btrfs_sync_log(trans, BTRFS_I(new_inode)->root,
9605 &ctx_dest);
9606 if (ret)
9607 commit_transaction = true;
9608 }
9609 if (commit_transaction) {
9610 ret = btrfs_commit_transaction(trans);
9611 } else {
9612 int ret2;
9613
9614 ret2 = btrfs_end_transaction(trans);
9615 ret = ret ? ret : ret2;
9616 }
9617 out_notrans:
9618 if (new_ino == BTRFS_FIRST_FREE_OBJECTID)
9619 up_read(&fs_info->subvol_sem);
9620 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
9621 up_read(&fs_info->subvol_sem);
9622
9623 return ret;
9624 }
9625
9626 static int btrfs_whiteout_for_rename(struct btrfs_trans_handle *trans,
9627 struct btrfs_root *root,
9628 struct inode *dir,
9629 struct dentry *dentry)
9630 {
9631 int ret;
9632 struct inode *inode;
9633 u64 objectid;
9634 u64 index;
9635
9636 ret = btrfs_find_free_ino(root, &objectid);
9637 if (ret)
9638 return ret;
9639
9640 inode = btrfs_new_inode(trans, root, dir,
9641 dentry->d_name.name,
9642 dentry->d_name.len,
9643 btrfs_ino(BTRFS_I(dir)),
9644 objectid,
9645 S_IFCHR | WHITEOUT_MODE,
9646 &index);
9647
9648 if (IS_ERR(inode)) {
9649 ret = PTR_ERR(inode);
9650 return ret;
9651 }
9652
9653 inode->i_op = &btrfs_special_inode_operations;
9654 init_special_inode(inode, inode->i_mode,
9655 WHITEOUT_DEV);
9656
9657 ret = btrfs_init_inode_security(trans, inode, dir,
9658 &dentry->d_name);
9659 if (ret)
9660 goto out;
9661
9662 ret = btrfs_add_nondir(trans, BTRFS_I(dir), dentry,
9663 BTRFS_I(inode), 0, index);
9664 if (ret)
9665 goto out;
9666
9667 ret = btrfs_update_inode(trans, root, inode);
9668 out:
9669 unlock_new_inode(inode);
9670 if (ret)
9671 inode_dec_link_count(inode);
9672 iput(inode);
9673
9674 return ret;
9675 }
9676
9677 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
9678 struct inode *new_dir, struct dentry *new_dentry,
9679 unsigned int flags)
9680 {
9681 struct btrfs_fs_info *fs_info = btrfs_sb(old_dir->i_sb);
9682 struct btrfs_trans_handle *trans;
9683 unsigned int trans_num_items;
9684 struct btrfs_root *root = BTRFS_I(old_dir)->root;
9685 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
9686 struct inode *new_inode = d_inode(new_dentry);
9687 struct inode *old_inode = d_inode(old_dentry);
9688 u64 index = 0;
9689 u64 root_objectid;
9690 int ret;
9691 u64 old_ino = btrfs_ino(BTRFS_I(old_inode));
9692 bool log_pinned = false;
9693 struct btrfs_log_ctx ctx;
9694 bool sync_log = false;
9695 bool commit_transaction = false;
9696
9697 if (btrfs_ino(BTRFS_I(new_dir)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
9698 return -EPERM;
9699
9700 /* we only allow rename subvolume link between subvolumes */
9701 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
9702 return -EXDEV;
9703
9704 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
9705 (new_inode && btrfs_ino(BTRFS_I(new_inode)) == BTRFS_FIRST_FREE_OBJECTID))
9706 return -ENOTEMPTY;
9707
9708 if (S_ISDIR(old_inode->i_mode) && new_inode &&
9709 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
9710 return -ENOTEMPTY;
9711
9712
9713 /* check for collisions, even if the name isn't there */
9714 ret = btrfs_check_dir_item_collision(dest, new_dir->i_ino,
9715 new_dentry->d_name.name,
9716 new_dentry->d_name.len);
9717
9718 if (ret) {
9719 if (ret == -EEXIST) {
9720 /* we shouldn't get
9721 * eexist without a new_inode */
9722 if (WARN_ON(!new_inode)) {
9723 return ret;
9724 }
9725 } else {
9726 /* maybe -EOVERFLOW */
9727 return ret;
9728 }
9729 }
9730 ret = 0;
9731
9732 /*
9733 * we're using rename to replace one file with another. Start IO on it
9734 * now so we don't add too much work to the end of the transaction
9735 */
9736 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size)
9737 filemap_flush(old_inode->i_mapping);
9738
9739 /* close the racy window with snapshot create/destroy ioctl */
9740 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
9741 down_read(&fs_info->subvol_sem);
9742 /*
9743 * We want to reserve the absolute worst case amount of items. So if
9744 * both inodes are subvols and we need to unlink them then that would
9745 * require 4 item modifications, but if they are both normal inodes it
9746 * would require 5 item modifications, so we'll assume they are normal
9747 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
9748 * should cover the worst case number of items we'll modify.
9749 * If our rename has the whiteout flag, we need more 5 units for the
9750 * new inode (1 inode item, 1 inode ref, 2 dir items and 1 xattr item
9751 * when selinux is enabled).
9752 */
9753 trans_num_items = 11;
9754 if (flags & RENAME_WHITEOUT)
9755 trans_num_items += 5;
9756 trans = btrfs_start_transaction(root, trans_num_items);
9757 if (IS_ERR(trans)) {
9758 ret = PTR_ERR(trans);
9759 goto out_notrans;
9760 }
9761
9762 if (dest != root)
9763 btrfs_record_root_in_trans(trans, dest);
9764
9765 ret = btrfs_set_inode_index(BTRFS_I(new_dir), &index);
9766 if (ret)
9767 goto out_fail;
9768
9769 BTRFS_I(old_inode)->dir_index = 0ULL;
9770 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
9771 /* force full log commit if subvolume involved. */
9772 btrfs_set_log_full_commit(fs_info, trans);
9773 } else {
9774 btrfs_pin_log_trans(root);
9775 log_pinned = true;
9776 ret = btrfs_insert_inode_ref(trans, dest,
9777 new_dentry->d_name.name,
9778 new_dentry->d_name.len,
9779 old_ino,
9780 btrfs_ino(BTRFS_I(new_dir)), index);
9781 if (ret)
9782 goto out_fail;
9783 }
9784
9785 inode_inc_iversion(old_dir);
9786 inode_inc_iversion(new_dir);
9787 inode_inc_iversion(old_inode);
9788 old_dir->i_ctime = old_dir->i_mtime =
9789 new_dir->i_ctime = new_dir->i_mtime =
9790 old_inode->i_ctime = current_time(old_dir);
9791
9792 if (old_dentry->d_parent != new_dentry->d_parent)
9793 btrfs_record_unlink_dir(trans, BTRFS_I(old_dir),
9794 BTRFS_I(old_inode), 1);
9795
9796 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
9797 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
9798 ret = btrfs_unlink_subvol(trans, old_dir, root_objectid,
9799 old_dentry->d_name.name,
9800 old_dentry->d_name.len);
9801 } else {
9802 ret = __btrfs_unlink_inode(trans, root, BTRFS_I(old_dir),
9803 BTRFS_I(d_inode(old_dentry)),
9804 old_dentry->d_name.name,
9805 old_dentry->d_name.len);
9806 if (!ret)
9807 ret = btrfs_update_inode(trans, root, old_inode);
9808 }
9809 if (ret) {
9810 btrfs_abort_transaction(trans, ret);
9811 goto out_fail;
9812 }
9813
9814 if (new_inode) {
9815 inode_inc_iversion(new_inode);
9816 new_inode->i_ctime = current_time(new_inode);
9817 if (unlikely(btrfs_ino(BTRFS_I(new_inode)) ==
9818 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
9819 root_objectid = BTRFS_I(new_inode)->location.objectid;
9820 ret = btrfs_unlink_subvol(trans, new_dir, root_objectid,
9821 new_dentry->d_name.name,
9822 new_dentry->d_name.len);
9823 BUG_ON(new_inode->i_nlink == 0);
9824 } else {
9825 ret = btrfs_unlink_inode(trans, dest, BTRFS_I(new_dir),
9826 BTRFS_I(d_inode(new_dentry)),
9827 new_dentry->d_name.name,
9828 new_dentry->d_name.len);
9829 }
9830 if (!ret && new_inode->i_nlink == 0)
9831 ret = btrfs_orphan_add(trans,
9832 BTRFS_I(d_inode(new_dentry)));
9833 if (ret) {
9834 btrfs_abort_transaction(trans, ret);
9835 goto out_fail;
9836 }
9837 }
9838
9839 ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode),
9840 new_dentry->d_name.name,
9841 new_dentry->d_name.len, 0, index);
9842 if (ret) {
9843 btrfs_abort_transaction(trans, ret);
9844 goto out_fail;
9845 }
9846
9847 if (old_inode->i_nlink == 1)
9848 BTRFS_I(old_inode)->dir_index = index;
9849
9850 if (log_pinned) {
9851 struct dentry *parent = new_dentry->d_parent;
9852
9853 btrfs_init_log_ctx(&ctx, old_inode);
9854 ret = btrfs_log_new_name(trans, BTRFS_I(old_inode),
9855 BTRFS_I(old_dir), parent,
9856 false, &ctx);
9857 if (ret == BTRFS_NEED_LOG_SYNC)
9858 sync_log = true;
9859 else if (ret == BTRFS_NEED_TRANS_COMMIT)
9860 commit_transaction = true;
9861 ret = 0;
9862 btrfs_end_log_trans(root);
9863 log_pinned = false;
9864 }
9865
9866 if (flags & RENAME_WHITEOUT) {
9867 ret = btrfs_whiteout_for_rename(trans, root, old_dir,
9868 old_dentry);
9869
9870 if (ret) {
9871 btrfs_abort_transaction(trans, ret);
9872 goto out_fail;
9873 }
9874 }
9875 out_fail:
9876 /*
9877 * If we have pinned the log and an error happened, we unpin tasks
9878 * trying to sync the log and force them to fallback to a transaction
9879 * commit if the log currently contains any of the inodes involved in
9880 * this rename operation (to ensure we do not persist a log with an
9881 * inconsistent state for any of these inodes or leading to any
9882 * inconsistencies when replayed). If the transaction was aborted, the
9883 * abortion reason is propagated to userspace when attempting to commit
9884 * the transaction. If the log does not contain any of these inodes, we
9885 * allow the tasks to sync it.
9886 */
9887 if (ret && log_pinned) {
9888 if (btrfs_inode_in_log(BTRFS_I(old_dir), fs_info->generation) ||
9889 btrfs_inode_in_log(BTRFS_I(new_dir), fs_info->generation) ||
9890 btrfs_inode_in_log(BTRFS_I(old_inode), fs_info->generation) ||
9891 (new_inode &&
9892 btrfs_inode_in_log(BTRFS_I(new_inode), fs_info->generation)))
9893 btrfs_set_log_full_commit(fs_info, trans);
9894
9895 btrfs_end_log_trans(root);
9896 log_pinned = false;
9897 }
9898 if (!ret && sync_log) {
9899 ret = btrfs_sync_log(trans, BTRFS_I(old_inode)->root, &ctx);
9900 if (ret)
9901 commit_transaction = true;
9902 }
9903 if (commit_transaction) {
9904 ret = btrfs_commit_transaction(trans);
9905 } else {
9906 int ret2;
9907
9908 ret2 = btrfs_end_transaction(trans);
9909 ret = ret ? ret : ret2;
9910 }
9911 out_notrans:
9912 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
9913 up_read(&fs_info->subvol_sem);
9914
9915 return ret;
9916 }
9917
9918 static int btrfs_rename2(struct inode *old_dir, struct dentry *old_dentry,
9919 struct inode *new_dir, struct dentry *new_dentry,
9920 unsigned int flags)
9921 {
9922 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
9923 return -EINVAL;
9924
9925 if (flags & RENAME_EXCHANGE)
9926 return btrfs_rename_exchange(old_dir, old_dentry, new_dir,
9927 new_dentry);
9928
9929 return btrfs_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
9930 }
9931
9932 struct btrfs_delalloc_work {
9933 struct inode *inode;
9934 struct completion completion;
9935 struct list_head list;
9936 struct btrfs_work work;
9937 };
9938
9939 static void btrfs_run_delalloc_work(struct btrfs_work *work)
9940 {
9941 struct btrfs_delalloc_work *delalloc_work;
9942 struct inode *inode;
9943
9944 delalloc_work = container_of(work, struct btrfs_delalloc_work,
9945 work);
9946 inode = delalloc_work->inode;
9947 filemap_flush(inode->i_mapping);
9948 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
9949 &BTRFS_I(inode)->runtime_flags))
9950 filemap_flush(inode->i_mapping);
9951
9952 iput(inode);
9953 complete(&delalloc_work->completion);
9954 }
9955
9956 static struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode)
9957 {
9958 struct btrfs_delalloc_work *work;
9959
9960 work = kmalloc(sizeof(*work), GFP_NOFS);
9961 if (!work)
9962 return NULL;
9963
9964 init_completion(&work->completion);
9965 INIT_LIST_HEAD(&work->list);
9966 work->inode = inode;
9967 WARN_ON_ONCE(!inode);
9968 btrfs_init_work(&work->work, btrfs_flush_delalloc_helper,
9969 btrfs_run_delalloc_work, NULL, NULL);
9970
9971 return work;
9972 }
9973
9974 /*
9975 * some fairly slow code that needs optimization. This walks the list
9976 * of all the inodes with pending delalloc and forces them to disk.
9977 */
9978 static int start_delalloc_inodes(struct btrfs_root *root, int nr)
9979 {
9980 struct btrfs_inode *binode;
9981 struct inode *inode;
9982 struct btrfs_delalloc_work *work, *next;
9983 struct list_head works;
9984 struct list_head splice;
9985 int ret = 0;
9986
9987 INIT_LIST_HEAD(&works);
9988 INIT_LIST_HEAD(&splice);
9989
9990 mutex_lock(&root->delalloc_mutex);
9991 spin_lock(&root->delalloc_lock);
9992 list_splice_init(&root->delalloc_inodes, &splice);
9993 while (!list_empty(&splice)) {
9994 binode = list_entry(splice.next, struct btrfs_inode,
9995 delalloc_inodes);
9996
9997 list_move_tail(&binode->delalloc_inodes,
9998 &root->delalloc_inodes);
9999 inode = igrab(&binode->vfs_inode);
10000 if (!inode) {
10001 cond_resched_lock(&root->delalloc_lock);
10002 continue;
10003 }
10004 spin_unlock(&root->delalloc_lock);
10005
10006 work = btrfs_alloc_delalloc_work(inode);
10007 if (!work) {
10008 iput(inode);
10009 ret = -ENOMEM;
10010 goto out;
10011 }
10012 list_add_tail(&work->list, &works);
10013 btrfs_queue_work(root->fs_info->flush_workers,
10014 &work->work);
10015 ret++;
10016 if (nr != -1 && ret >= nr)
10017 goto out;
10018 cond_resched();
10019 spin_lock(&root->delalloc_lock);
10020 }
10021 spin_unlock(&root->delalloc_lock);
10022
10023 out:
10024 list_for_each_entry_safe(work, next, &works, list) {
10025 list_del_init(&work->list);
10026 wait_for_completion(&work->completion);
10027 kfree(work);
10028 }
10029
10030 if (!list_empty(&splice)) {
10031 spin_lock(&root->delalloc_lock);
10032 list_splice_tail(&splice, &root->delalloc_inodes);
10033 spin_unlock(&root->delalloc_lock);
10034 }
10035 mutex_unlock(&root->delalloc_mutex);
10036 return ret;
10037 }
10038
10039 int btrfs_start_delalloc_inodes(struct btrfs_root *root)
10040 {
10041 struct btrfs_fs_info *fs_info = root->fs_info;
10042 int ret;
10043
10044 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
10045 return -EROFS;
10046
10047 ret = start_delalloc_inodes(root, -1);
10048 if (ret > 0)
10049 ret = 0;
10050 return ret;
10051 }
10052
10053 int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, int nr)
10054 {
10055 struct btrfs_root *root;
10056 struct list_head splice;
10057 int ret;
10058
10059 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
10060 return -EROFS;
10061
10062 INIT_LIST_HEAD(&splice);
10063
10064 mutex_lock(&fs_info->delalloc_root_mutex);
10065 spin_lock(&fs_info->delalloc_root_lock);
10066 list_splice_init(&fs_info->delalloc_roots, &splice);
10067 while (!list_empty(&splice) && nr) {
10068 root = list_first_entry(&splice, struct btrfs_root,
10069 delalloc_root);
10070 root = btrfs_grab_fs_root(root);
10071 BUG_ON(!root);
10072 list_move_tail(&root->delalloc_root,
10073 &fs_info->delalloc_roots);
10074 spin_unlock(&fs_info->delalloc_root_lock);
10075
10076 ret = start_delalloc_inodes(root, nr);
10077 btrfs_put_fs_root(root);
10078 if (ret < 0)
10079 goto out;
10080
10081 if (nr != -1) {
10082 nr -= ret;
10083 WARN_ON(nr < 0);
10084 }
10085 spin_lock(&fs_info->delalloc_root_lock);
10086 }
10087 spin_unlock(&fs_info->delalloc_root_lock);
10088
10089 ret = 0;
10090 out:
10091 if (!list_empty(&splice)) {
10092 spin_lock(&fs_info->delalloc_root_lock);
10093 list_splice_tail(&splice, &fs_info->delalloc_roots);
10094 spin_unlock(&fs_info->delalloc_root_lock);
10095 }
10096 mutex_unlock(&fs_info->delalloc_root_mutex);
10097 return ret;
10098 }
10099
10100 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
10101 const char *symname)
10102 {
10103 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
10104 struct btrfs_trans_handle *trans;
10105 struct btrfs_root *root = BTRFS_I(dir)->root;
10106 struct btrfs_path *path;
10107 struct btrfs_key key;
10108 struct inode *inode = NULL;
10109 int err;
10110 u64 objectid;
10111 u64 index = 0;
10112 int name_len;
10113 int datasize;
10114 unsigned long ptr;
10115 struct btrfs_file_extent_item *ei;
10116 struct extent_buffer *leaf;
10117
10118 name_len = strlen(symname);
10119 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info))
10120 return -ENAMETOOLONG;
10121
10122 /*
10123 * 2 items for inode item and ref
10124 * 2 items for dir items
10125 * 1 item for updating parent inode item
10126 * 1 item for the inline extent item
10127 * 1 item for xattr if selinux is on
10128 */
10129 trans = btrfs_start_transaction(root, 7);
10130 if (IS_ERR(trans))
10131 return PTR_ERR(trans);
10132
10133 err = btrfs_find_free_ino(root, &objectid);
10134 if (err)
10135 goto out_unlock;
10136
10137 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
10138 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)),
10139 objectid, S_IFLNK|S_IRWXUGO, &index);
10140 if (IS_ERR(inode)) {
10141 err = PTR_ERR(inode);
10142 inode = NULL;
10143 goto out_unlock;
10144 }
10145
10146 /*
10147 * If the active LSM wants to access the inode during
10148 * d_instantiate it needs these. Smack checks to see
10149 * if the filesystem supports xattrs by looking at the
10150 * ops vector.
10151 */
10152 inode->i_fop = &btrfs_file_operations;
10153 inode->i_op = &btrfs_file_inode_operations;
10154 inode->i_mapping->a_ops = &btrfs_aops;
10155 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
10156
10157 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
10158 if (err)
10159 goto out_unlock;
10160
10161 path = btrfs_alloc_path();
10162 if (!path) {
10163 err = -ENOMEM;
10164 goto out_unlock;
10165 }
10166 key.objectid = btrfs_ino(BTRFS_I(inode));
10167 key.offset = 0;
10168 key.type = BTRFS_EXTENT_DATA_KEY;
10169 datasize = btrfs_file_extent_calc_inline_size(name_len);
10170 err = btrfs_insert_empty_item(trans, root, path, &key,
10171 datasize);
10172 if (err) {
10173 btrfs_free_path(path);
10174 goto out_unlock;
10175 }
10176 leaf = path->nodes[0];
10177 ei = btrfs_item_ptr(leaf, path->slots[0],
10178 struct btrfs_file_extent_item);
10179 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
10180 btrfs_set_file_extent_type(leaf, ei,
10181 BTRFS_FILE_EXTENT_INLINE);
10182 btrfs_set_file_extent_encryption(leaf, ei, 0);
10183 btrfs_set_file_extent_compression(leaf, ei, 0);
10184 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
10185 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
10186
10187 ptr = btrfs_file_extent_inline_start(ei);
10188 write_extent_buffer(leaf, symname, ptr, name_len);
10189 btrfs_mark_buffer_dirty(leaf);
10190 btrfs_free_path(path);
10191
10192 inode->i_op = &btrfs_symlink_inode_operations;
10193 inode_nohighmem(inode);
10194 inode->i_mapping->a_ops = &btrfs_symlink_aops;
10195 inode_set_bytes(inode, name_len);
10196 btrfs_i_size_write(BTRFS_I(inode), name_len);
10197 err = btrfs_update_inode(trans, root, inode);
10198 /*
10199 * Last step, add directory indexes for our symlink inode. This is the
10200 * last step to avoid extra cleanup of these indexes if an error happens
10201 * elsewhere above.
10202 */
10203 if (!err)
10204 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry,
10205 BTRFS_I(inode), 0, index);
10206 if (err)
10207 goto out_unlock;
10208
10209 d_instantiate_new(dentry, inode);
10210
10211 out_unlock:
10212 btrfs_end_transaction(trans);
10213 if (err && inode) {
10214 inode_dec_link_count(inode);
10215 discard_new_inode(inode);
10216 }
10217 btrfs_btree_balance_dirty(fs_info);
10218 return err;
10219 }
10220
10221 static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
10222 u64 start, u64 num_bytes, u64 min_size,
10223 loff_t actual_len, u64 *alloc_hint,
10224 struct btrfs_trans_handle *trans)
10225 {
10226 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
10227 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
10228 struct extent_map *em;
10229 struct btrfs_root *root = BTRFS_I(inode)->root;
10230 struct btrfs_key ins;
10231 u64 cur_offset = start;
10232 u64 i_size;
10233 u64 cur_bytes;
10234 u64 last_alloc = (u64)-1;
10235 int ret = 0;
10236 bool own_trans = true;
10237 u64 end = start + num_bytes - 1;
10238
10239 if (trans)
10240 own_trans = false;
10241 while (num_bytes > 0) {
10242 if (own_trans) {
10243 trans = btrfs_start_transaction(root, 3);
10244 if (IS_ERR(trans)) {
10245 ret = PTR_ERR(trans);
10246 break;
10247 }
10248 }
10249
10250 cur_bytes = min_t(u64, num_bytes, SZ_256M);
10251 cur_bytes = max(cur_bytes, min_size);
10252 /*
10253 * If we are severely fragmented we could end up with really
10254 * small allocations, so if the allocator is returning small
10255 * chunks lets make its job easier by only searching for those
10256 * sized chunks.
10257 */
10258 cur_bytes = min(cur_bytes, last_alloc);
10259 ret = btrfs_reserve_extent(root, cur_bytes, cur_bytes,
10260 min_size, 0, *alloc_hint, &ins, 1, 0);
10261 if (ret) {
10262 if (own_trans)
10263 btrfs_end_transaction(trans);
10264 break;
10265 }
10266 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
10267
10268 last_alloc = ins.offset;
10269 ret = insert_reserved_file_extent(trans, inode,
10270 cur_offset, ins.objectid,
10271 ins.offset, ins.offset,
10272 ins.offset, 0, 0, 0,
10273 BTRFS_FILE_EXTENT_PREALLOC);
10274 if (ret) {
10275 btrfs_free_reserved_extent(fs_info, ins.objectid,
10276 ins.offset, 0);
10277 btrfs_abort_transaction(trans, ret);
10278 if (own_trans)
10279 btrfs_end_transaction(trans);
10280 break;
10281 }
10282
10283 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset,
10284 cur_offset + ins.offset -1, 0);
10285
10286 em = alloc_extent_map();
10287 if (!em) {
10288 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
10289 &BTRFS_I(inode)->runtime_flags);
10290 goto next;
10291 }
10292
10293 em->start = cur_offset;
10294 em->orig_start = cur_offset;
10295 em->len = ins.offset;
10296 em->block_start = ins.objectid;
10297 em->block_len = ins.offset;
10298 em->orig_block_len = ins.offset;
10299 em->ram_bytes = ins.offset;
10300 em->bdev = fs_info->fs_devices->latest_bdev;
10301 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
10302 em->generation = trans->transid;
10303
10304 while (1) {
10305 write_lock(&em_tree->lock);
10306 ret = add_extent_mapping(em_tree, em, 1);
10307 write_unlock(&em_tree->lock);
10308 if (ret != -EEXIST)
10309 break;
10310 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset,
10311 cur_offset + ins.offset - 1,
10312 0);
10313 }
10314 free_extent_map(em);
10315 next:
10316 num_bytes -= ins.offset;
10317 cur_offset += ins.offset;
10318 *alloc_hint = ins.objectid + ins.offset;
10319
10320 inode_inc_iversion(inode);
10321 inode->i_ctime = current_time(inode);
10322 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
10323 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
10324 (actual_len > inode->i_size) &&
10325 (cur_offset > inode->i_size)) {
10326 if (cur_offset > actual_len)
10327 i_size = actual_len;
10328 else
10329 i_size = cur_offset;
10330 i_size_write(inode, i_size);
10331 btrfs_ordered_update_i_size(inode, i_size, NULL);
10332 }
10333
10334 ret = btrfs_update_inode(trans, root, inode);
10335
10336 if (ret) {
10337 btrfs_abort_transaction(trans, ret);
10338 if (own_trans)
10339 btrfs_end_transaction(trans);
10340 break;
10341 }
10342
10343 if (own_trans)
10344 btrfs_end_transaction(trans);
10345 }
10346 if (cur_offset < end)
10347 btrfs_free_reserved_data_space(inode, NULL, cur_offset,
10348 end - cur_offset + 1);
10349 return ret;
10350 }
10351
10352 int btrfs_prealloc_file_range(struct inode *inode, int mode,
10353 u64 start, u64 num_bytes, u64 min_size,
10354 loff_t actual_len, u64 *alloc_hint)
10355 {
10356 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
10357 min_size, actual_len, alloc_hint,
10358 NULL);
10359 }
10360
10361 int btrfs_prealloc_file_range_trans(struct inode *inode,
10362 struct btrfs_trans_handle *trans, int mode,
10363 u64 start, u64 num_bytes, u64 min_size,
10364 loff_t actual_len, u64 *alloc_hint)
10365 {
10366 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
10367 min_size, actual_len, alloc_hint, trans);
10368 }
10369
10370 static int btrfs_set_page_dirty(struct page *page)
10371 {
10372 return __set_page_dirty_nobuffers(page);
10373 }
10374
10375 static int btrfs_permission(struct inode *inode, int mask)
10376 {
10377 struct btrfs_root *root = BTRFS_I(inode)->root;
10378 umode_t mode = inode->i_mode;
10379
10380 if (mask & MAY_WRITE &&
10381 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) {
10382 if (btrfs_root_readonly(root))
10383 return -EROFS;
10384 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
10385 return -EACCES;
10386 }
10387 return generic_permission(inode, mask);
10388 }
10389
10390 static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
10391 {
10392 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
10393 struct btrfs_trans_handle *trans;
10394 struct btrfs_root *root = BTRFS_I(dir)->root;
10395 struct inode *inode = NULL;
10396 u64 objectid;
10397 u64 index;
10398 int ret = 0;
10399
10400 /*
10401 * 5 units required for adding orphan entry
10402 */
10403 trans = btrfs_start_transaction(root, 5);
10404 if (IS_ERR(trans))
10405 return PTR_ERR(trans);
10406
10407 ret = btrfs_find_free_ino(root, &objectid);
10408 if (ret)
10409 goto out;
10410
10411 inode = btrfs_new_inode(trans, root, dir, NULL, 0,
10412 btrfs_ino(BTRFS_I(dir)), objectid, mode, &index);
10413 if (IS_ERR(inode)) {
10414 ret = PTR_ERR(inode);
10415 inode = NULL;
10416 goto out;
10417 }
10418
10419 inode->i_fop = &btrfs_file_operations;
10420 inode->i_op = &btrfs_file_inode_operations;
10421
10422 inode->i_mapping->a_ops = &btrfs_aops;
10423 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
10424
10425 ret = btrfs_init_inode_security(trans, inode, dir, NULL);
10426 if (ret)
10427 goto out;
10428
10429 ret = btrfs_update_inode(trans, root, inode);
10430 if (ret)
10431 goto out;
10432 ret = btrfs_orphan_add(trans, BTRFS_I(inode));
10433 if (ret)
10434 goto out;
10435
10436 /*
10437 * We set number of links to 0 in btrfs_new_inode(), and here we set
10438 * it to 1 because d_tmpfile() will issue a warning if the count is 0,
10439 * through:
10440 *
10441 * d_tmpfile() -> inode_dec_link_count() -> drop_nlink()
10442 */
10443 set_nlink(inode, 1);
10444 d_tmpfile(dentry, inode);
10445 unlock_new_inode(inode);
10446 mark_inode_dirty(inode);
10447 out:
10448 btrfs_end_transaction(trans);
10449 if (ret && inode)
10450 discard_new_inode(inode);
10451 btrfs_btree_balance_dirty(fs_info);
10452 return ret;
10453 }
10454
10455 __attribute__((const))
10456 static int btrfs_readpage_io_failed_hook(struct page *page, int failed_mirror)
10457 {
10458 return -EAGAIN;
10459 }
10460
10461 static void btrfs_check_extent_io_range(void *private_data, const char *caller,
10462 u64 start, u64 end)
10463 {
10464 struct inode *inode = private_data;
10465 u64 isize;
10466
10467 isize = i_size_read(inode);
10468 if (end >= PAGE_SIZE && (end % 2) == 0 && end != isize - 1) {
10469 btrfs_debug_rl(BTRFS_I(inode)->root->fs_info,
10470 "%s: ino %llu isize %llu odd range [%llu,%llu]",
10471 caller, btrfs_ino(BTRFS_I(inode)), isize, start, end);
10472 }
10473 }
10474
10475 void btrfs_set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end)
10476 {
10477 struct inode *inode = tree->private_data;
10478 unsigned long index = start >> PAGE_SHIFT;
10479 unsigned long end_index = end >> PAGE_SHIFT;
10480 struct page *page;
10481
10482 while (index <= end_index) {
10483 page = find_get_page(inode->i_mapping, index);
10484 ASSERT(page); /* Pages should be in the extent_io_tree */
10485 set_page_writeback(page);
10486 put_page(page);
10487 index++;
10488 }
10489 }
10490
10491 static const struct inode_operations btrfs_dir_inode_operations = {
10492 .getattr = btrfs_getattr,
10493 .lookup = btrfs_lookup,
10494 .create = btrfs_create,
10495 .unlink = btrfs_unlink,
10496 .link = btrfs_link,
10497 .mkdir = btrfs_mkdir,
10498 .rmdir = btrfs_rmdir,
10499 .rename = btrfs_rename2,
10500 .symlink = btrfs_symlink,
10501 .setattr = btrfs_setattr,
10502 .mknod = btrfs_mknod,
10503 .listxattr = btrfs_listxattr,
10504 .permission = btrfs_permission,
10505 .get_acl = btrfs_get_acl,
10506 .set_acl = btrfs_set_acl,
10507 .update_time = btrfs_update_time,
10508 .tmpfile = btrfs_tmpfile,
10509 };
10510 static const struct inode_operations btrfs_dir_ro_inode_operations = {
10511 .lookup = btrfs_lookup,
10512 .permission = btrfs_permission,
10513 .update_time = btrfs_update_time,
10514 };
10515
10516 static const struct file_operations btrfs_dir_file_operations = {
10517 .llseek = generic_file_llseek,
10518 .read = generic_read_dir,
10519 .iterate_shared = btrfs_real_readdir,
10520 .open = btrfs_opendir,
10521 .unlocked_ioctl = btrfs_ioctl,
10522 #ifdef CONFIG_COMPAT
10523 .compat_ioctl = btrfs_compat_ioctl,
10524 #endif
10525 .release = btrfs_release_file,
10526 .fsync = btrfs_sync_file,
10527 };
10528
10529 static const struct extent_io_ops btrfs_extent_io_ops = {
10530 /* mandatory callbacks */
10531 .submit_bio_hook = btrfs_submit_bio_hook,
10532 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
10533 .readpage_io_failed_hook = btrfs_readpage_io_failed_hook,
10534
10535 /* optional callbacks */
10536 .fill_delalloc = run_delalloc_range,
10537 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
10538 .writepage_start_hook = btrfs_writepage_start_hook,
10539 .set_bit_hook = btrfs_set_bit_hook,
10540 .clear_bit_hook = btrfs_clear_bit_hook,
10541 .merge_extent_hook = btrfs_merge_extent_hook,
10542 .split_extent_hook = btrfs_split_extent_hook,
10543 .check_extent_io_range = btrfs_check_extent_io_range,
10544 };
10545
10546 /*
10547 * btrfs doesn't support the bmap operation because swapfiles
10548 * use bmap to make a mapping of extents in the file. They assume
10549 * these extents won't change over the life of the file and they
10550 * use the bmap result to do IO directly to the drive.
10551 *
10552 * the btrfs bmap call would return logical addresses that aren't
10553 * suitable for IO and they also will change frequently as COW
10554 * operations happen. So, swapfile + btrfs == corruption.
10555 *
10556 * For now we're avoiding this by dropping bmap.
10557 */
10558 static const struct address_space_operations btrfs_aops = {
10559 .readpage = btrfs_readpage,
10560 .writepage = btrfs_writepage,
10561 .writepages = btrfs_writepages,
10562 .readpages = btrfs_readpages,
10563 .direct_IO = btrfs_direct_IO,
10564 .invalidatepage = btrfs_invalidatepage,
10565 .releasepage = btrfs_releasepage,
10566 .set_page_dirty = btrfs_set_page_dirty,
10567 .error_remove_page = generic_error_remove_page,
10568 };
10569
10570 static const struct address_space_operations btrfs_symlink_aops = {
10571 .readpage = btrfs_readpage,
10572 .writepage = btrfs_writepage,
10573 .invalidatepage = btrfs_invalidatepage,
10574 .releasepage = btrfs_releasepage,
10575 };
10576
10577 static const struct inode_operations btrfs_file_inode_operations = {
10578 .getattr = btrfs_getattr,
10579 .setattr = btrfs_setattr,
10580 .listxattr = btrfs_listxattr,
10581 .permission = btrfs_permission,
10582 .fiemap = btrfs_fiemap,
10583 .get_acl = btrfs_get_acl,
10584 .set_acl = btrfs_set_acl,
10585 .update_time = btrfs_update_time,
10586 };
10587 static const struct inode_operations btrfs_special_inode_operations = {
10588 .getattr = btrfs_getattr,
10589 .setattr = btrfs_setattr,
10590 .permission = btrfs_permission,
10591 .listxattr = btrfs_listxattr,
10592 .get_acl = btrfs_get_acl,
10593 .set_acl = btrfs_set_acl,
10594 .update_time = btrfs_update_time,
10595 };
10596 static const struct inode_operations btrfs_symlink_inode_operations = {
10597 .get_link = page_get_link,
10598 .getattr = btrfs_getattr,
10599 .setattr = btrfs_setattr,
10600 .permission = btrfs_permission,
10601 .listxattr = btrfs_listxattr,
10602 .update_time = btrfs_update_time,
10603 };
10604
10605 const struct dentry_operations btrfs_dentry_operations = {
10606 .d_delete = btrfs_dentry_delete,
10607 };
Linux with added FPC-III support