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Linux 3.12.5
[linux/fpc-iii.git] / fs / btrfs / ioctl.c
blob9d46f60cb9439ab3a41ab83f2f323f13aa564590
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19 #include <linux/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.h>
23 #include <linux/fs.h>
24 #include <linux/fsnotify.h>
25 #include <linux/pagemap.h>
26 #include <linux/highmem.h>
27 #include <linux/time.h>
28 #include <linux/init.h>
29 #include <linux/string.h>
30 #include <linux/backing-dev.h>
31 #include <linux/mount.h>
32 #include <linux/mpage.h>
33 #include <linux/namei.h>
34 #include <linux/swap.h>
35 #include <linux/writeback.h>
36 #include <linux/statfs.h>
37 #include <linux/compat.h>
38 #include <linux/bit_spinlock.h>
39 #include <linux/security.h>
40 #include <linux/xattr.h>
41 #include <linux/vmalloc.h>
42 #include <linux/slab.h>
43 #include <linux/blkdev.h>
44 #include <linux/uuid.h>
45 #include <linux/btrfs.h>
46 #include <linux/uaccess.h>
47 #include "compat.h"
48 #include "ctree.h"
49 #include "disk-io.h"
50 #include "transaction.h"
51 #include "btrfs_inode.h"
52 #include "print-tree.h"
53 #include "volumes.h"
54 #include "locking.h"
55 #include "inode-map.h"
56 #include "backref.h"
57 #include "rcu-string.h"
58 #include "send.h"
59 #include "dev-replace.h"
60
61 static int btrfs_clone(struct inode *src, struct inode *inode,
62 u64 off, u64 olen, u64 olen_aligned, u64 destoff);
63
64 /* Mask out flags that are inappropriate for the given type of inode. */
65 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
66 {
67 if (S_ISDIR(mode))
68 return flags;
69 else if (S_ISREG(mode))
70 return flags & ~FS_DIRSYNC_FL;
71 else
72 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
73 }
74
75 /*
76 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
77 */
78 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
79 {
80 unsigned int iflags = 0;
81
82 if (flags & BTRFS_INODE_SYNC)
83 iflags |= FS_SYNC_FL;
84 if (flags & BTRFS_INODE_IMMUTABLE)
85 iflags |= FS_IMMUTABLE_FL;
86 if (flags & BTRFS_INODE_APPEND)
87 iflags |= FS_APPEND_FL;
88 if (flags & BTRFS_INODE_NODUMP)
89 iflags |= FS_NODUMP_FL;
90 if (flags & BTRFS_INODE_NOATIME)
91 iflags |= FS_NOATIME_FL;
92 if (flags & BTRFS_INODE_DIRSYNC)
93 iflags |= FS_DIRSYNC_FL;
94 if (flags & BTRFS_INODE_NODATACOW)
95 iflags |= FS_NOCOW_FL;
96
97 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
98 iflags |= FS_COMPR_FL;
99 else if (flags & BTRFS_INODE_NOCOMPRESS)
100 iflags |= FS_NOCOMP_FL;
101
102 return iflags;
103 }
104
105 /*
106 * Update inode->i_flags based on the btrfs internal flags.
107 */
108 void btrfs_update_iflags(struct inode *inode)
109 {
110 struct btrfs_inode *ip = BTRFS_I(inode);
111
112 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
113
114 if (ip->flags & BTRFS_INODE_SYNC)
115 inode->i_flags |= S_SYNC;
116 if (ip->flags & BTRFS_INODE_IMMUTABLE)
117 inode->i_flags |= S_IMMUTABLE;
118 if (ip->flags & BTRFS_INODE_APPEND)
119 inode->i_flags |= S_APPEND;
120 if (ip->flags & BTRFS_INODE_NOATIME)
121 inode->i_flags |= S_NOATIME;
122 if (ip->flags & BTRFS_INODE_DIRSYNC)
123 inode->i_flags |= S_DIRSYNC;
124 }
125
126 /*
127 * Inherit flags from the parent inode.
128 *
129 * Currently only the compression flags and the cow flags are inherited.
130 */
131 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
132 {
133 unsigned int flags;
134
135 if (!dir)
136 return;
137
138 flags = BTRFS_I(dir)->flags;
139
140 if (flags & BTRFS_INODE_NOCOMPRESS) {
141 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
142 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
143 } else if (flags & BTRFS_INODE_COMPRESS) {
144 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
145 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
146 }
147
148 if (flags & BTRFS_INODE_NODATACOW) {
149 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
150 if (S_ISREG(inode->i_mode))
151 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
152 }
153
154 btrfs_update_iflags(inode);
155 }
156
157 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
158 {
159 struct btrfs_inode *ip = BTRFS_I(file_inode(file));
160 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
161
162 if (copy_to_user(arg, &flags, sizeof(flags)))
163 return -EFAULT;
164 return 0;
165 }
166
167 static int check_flags(unsigned int flags)
168 {
169 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
170 FS_NOATIME_FL | FS_NODUMP_FL | \
171 FS_SYNC_FL | FS_DIRSYNC_FL | \
172 FS_NOCOMP_FL | FS_COMPR_FL |
173 FS_NOCOW_FL))
174 return -EOPNOTSUPP;
175
176 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
177 return -EINVAL;
178
179 return 0;
180 }
181
182 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
183 {
184 struct inode *inode = file_inode(file);
185 struct btrfs_inode *ip = BTRFS_I(inode);
186 struct btrfs_root *root = ip->root;
187 struct btrfs_trans_handle *trans;
188 unsigned int flags, oldflags;
189 int ret;
190 u64 ip_oldflags;
191 unsigned int i_oldflags;
192 umode_t mode;
193
194 if (btrfs_root_readonly(root))
195 return -EROFS;
196
197 if (copy_from_user(&flags, arg, sizeof(flags)))
198 return -EFAULT;
199
200 ret = check_flags(flags);
201 if (ret)
202 return ret;
203
204 if (!inode_owner_or_capable(inode))
205 return -EACCES;
206
207 ret = mnt_want_write_file(file);
208 if (ret)
209 return ret;
210
211 mutex_lock(&inode->i_mutex);
212
213 ip_oldflags = ip->flags;
214 i_oldflags = inode->i_flags;
215 mode = inode->i_mode;
216
217 flags = btrfs_mask_flags(inode->i_mode, flags);
218 oldflags = btrfs_flags_to_ioctl(ip->flags);
219 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
220 if (!capable(CAP_LINUX_IMMUTABLE)) {
221 ret = -EPERM;
222 goto out_unlock;
223 }
224 }
225
226 if (flags & FS_SYNC_FL)
227 ip->flags |= BTRFS_INODE_SYNC;
228 else
229 ip->flags &= ~BTRFS_INODE_SYNC;
230 if (flags & FS_IMMUTABLE_FL)
231 ip->flags |= BTRFS_INODE_IMMUTABLE;
232 else
233 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
234 if (flags & FS_APPEND_FL)
235 ip->flags |= BTRFS_INODE_APPEND;
236 else
237 ip->flags &= ~BTRFS_INODE_APPEND;
238 if (flags & FS_NODUMP_FL)
239 ip->flags |= BTRFS_INODE_NODUMP;
240 else
241 ip->flags &= ~BTRFS_INODE_NODUMP;
242 if (flags & FS_NOATIME_FL)
243 ip->flags |= BTRFS_INODE_NOATIME;
244 else
245 ip->flags &= ~BTRFS_INODE_NOATIME;
246 if (flags & FS_DIRSYNC_FL)
247 ip->flags |= BTRFS_INODE_DIRSYNC;
248 else
249 ip->flags &= ~BTRFS_INODE_DIRSYNC;
250 if (flags & FS_NOCOW_FL) {
251 if (S_ISREG(mode)) {
252 /*
253 * It's safe to turn csums off here, no extents exist.
254 * Otherwise we want the flag to reflect the real COW
255 * status of the file and will not set it.
256 */
257 if (inode->i_size == 0)
258 ip->flags |= BTRFS_INODE_NODATACOW
259 | BTRFS_INODE_NODATASUM;
260 } else {
261 ip->flags |= BTRFS_INODE_NODATACOW;
262 }
263 } else {
264 /*
265 * Revert back under same assuptions as above
266 */
267 if (S_ISREG(mode)) {
268 if (inode->i_size == 0)
269 ip->flags &= ~(BTRFS_INODE_NODATACOW
270 | BTRFS_INODE_NODATASUM);
271 } else {
272 ip->flags &= ~BTRFS_INODE_NODATACOW;
273 }
274 }
275
276 /*
277 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
278 * flag may be changed automatically if compression code won't make
279 * things smaller.
280 */
281 if (flags & FS_NOCOMP_FL) {
282 ip->flags &= ~BTRFS_INODE_COMPRESS;
283 ip->flags |= BTRFS_INODE_NOCOMPRESS;
284 } else if (flags & FS_COMPR_FL) {
285 ip->flags |= BTRFS_INODE_COMPRESS;
286 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
287 } else {
288 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
289 }
290
291 trans = btrfs_start_transaction(root, 1);
292 if (IS_ERR(trans)) {
293 ret = PTR_ERR(trans);
294 goto out_drop;
295 }
296
297 btrfs_update_iflags(inode);
298 inode_inc_iversion(inode);
299 inode->i_ctime = CURRENT_TIME;
300 ret = btrfs_update_inode(trans, root, inode);
301
302 btrfs_end_transaction(trans, root);
303 out_drop:
304 if (ret) {
305 ip->flags = ip_oldflags;
306 inode->i_flags = i_oldflags;
307 }
308
309 out_unlock:
310 mutex_unlock(&inode->i_mutex);
311 mnt_drop_write_file(file);
312 return ret;
313 }
314
315 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
316 {
317 struct inode *inode = file_inode(file);
318
319 return put_user(inode->i_generation, arg);
320 }
321
322 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
323 {
324 struct btrfs_fs_info *fs_info = btrfs_sb(fdentry(file)->d_sb);
325 struct btrfs_device *device;
326 struct request_queue *q;
327 struct fstrim_range range;
328 u64 minlen = ULLONG_MAX;
329 u64 num_devices = 0;
330 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
331 int ret;
332
333 if (!capable(CAP_SYS_ADMIN))
334 return -EPERM;
335
336 rcu_read_lock();
337 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
338 dev_list) {
339 if (!device->bdev)
340 continue;
341 q = bdev_get_queue(device->bdev);
342 if (blk_queue_discard(q)) {
343 num_devices++;
344 minlen = min((u64)q->limits.discard_granularity,
345 minlen);
346 }
347 }
348 rcu_read_unlock();
349
350 if (!num_devices)
351 return -EOPNOTSUPP;
352 if (copy_from_user(&range, arg, sizeof(range)))
353 return -EFAULT;
354 if (range.start > total_bytes ||
355 range.len < fs_info->sb->s_blocksize)
356 return -EINVAL;
357
358 range.len = min(range.len, total_bytes - range.start);
359 range.minlen = max(range.minlen, minlen);
360 ret = btrfs_trim_fs(fs_info->tree_root, &range);
361 if (ret < 0)
362 return ret;
363
364 if (copy_to_user(arg, &range, sizeof(range)))
365 return -EFAULT;
366
367 return 0;
368 }
369
370 int btrfs_is_empty_uuid(u8 *uuid)
371 {
372 static char empty_uuid[BTRFS_UUID_SIZE] = {0};
373
374 return !memcmp(uuid, empty_uuid, BTRFS_UUID_SIZE);
375 }
376
377 static noinline int create_subvol(struct inode *dir,
378 struct dentry *dentry,
379 char *name, int namelen,
380 u64 *async_transid,
381 struct btrfs_qgroup_inherit *inherit)
382 {
383 struct btrfs_trans_handle *trans;
384 struct btrfs_key key;
385 struct btrfs_root_item root_item;
386 struct btrfs_inode_item *inode_item;
387 struct extent_buffer *leaf;
388 struct btrfs_root *root = BTRFS_I(dir)->root;
389 struct btrfs_root *new_root;
390 struct btrfs_block_rsv block_rsv;
391 struct timespec cur_time = CURRENT_TIME;
392 int ret;
393 int err;
394 u64 objectid;
395 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
396 u64 index = 0;
397 u64 qgroup_reserved;
398 uuid_le new_uuid;
399
400 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
401 if (ret)
402 return ret;
403
404 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
405 /*
406 * The same as the snapshot creation, please see the comment
407 * of create_snapshot().
408 */
409 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
410 8, &qgroup_reserved, false);
411 if (ret)
412 return ret;
413
414 trans = btrfs_start_transaction(root, 0);
415 if (IS_ERR(trans)) {
416 ret = PTR_ERR(trans);
417 goto out;
418 }
419 trans->block_rsv = &block_rsv;
420 trans->bytes_reserved = block_rsv.size;
421
422 ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
423 if (ret)
424 goto fail;
425
426 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
427 0, objectid, NULL, 0, 0, 0);
428 if (IS_ERR(leaf)) {
429 ret = PTR_ERR(leaf);
430 goto fail;
431 }
432
433 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
434 btrfs_set_header_bytenr(leaf, leaf->start);
435 btrfs_set_header_generation(leaf, trans->transid);
436 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
437 btrfs_set_header_owner(leaf, objectid);
438
439 write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(leaf),
440 BTRFS_FSID_SIZE);
441 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
442 btrfs_header_chunk_tree_uuid(leaf),
443 BTRFS_UUID_SIZE);
444 btrfs_mark_buffer_dirty(leaf);
445
446 memset(&root_item, 0, sizeof(root_item));
447
448 inode_item = &root_item.inode;
449 btrfs_set_stack_inode_generation(inode_item, 1);
450 btrfs_set_stack_inode_size(inode_item, 3);
451 btrfs_set_stack_inode_nlink(inode_item, 1);
452 btrfs_set_stack_inode_nbytes(inode_item, root->leafsize);
453 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
454
455 btrfs_set_root_flags(&root_item, 0);
456 btrfs_set_root_limit(&root_item, 0);
457 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
458
459 btrfs_set_root_bytenr(&root_item, leaf->start);
460 btrfs_set_root_generation(&root_item, trans->transid);
461 btrfs_set_root_level(&root_item, 0);
462 btrfs_set_root_refs(&root_item, 1);
463 btrfs_set_root_used(&root_item, leaf->len);
464 btrfs_set_root_last_snapshot(&root_item, 0);
465
466 btrfs_set_root_generation_v2(&root_item,
467 btrfs_root_generation(&root_item));
468 uuid_le_gen(&new_uuid);
469 memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
470 btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
471 btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec);
472 root_item.ctime = root_item.otime;
473 btrfs_set_root_ctransid(&root_item, trans->transid);
474 btrfs_set_root_otransid(&root_item, trans->transid);
475
476 btrfs_tree_unlock(leaf);
477 free_extent_buffer(leaf);
478 leaf = NULL;
479
480 btrfs_set_root_dirid(&root_item, new_dirid);
481
482 key.objectid = objectid;
483 key.offset = 0;
484 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
485 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
486 &root_item);
487 if (ret)
488 goto fail;
489
490 key.offset = (u64)-1;
491 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
492 if (IS_ERR(new_root)) {
493 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
494 ret = PTR_ERR(new_root);
495 goto fail;
496 }
497
498 btrfs_record_root_in_trans(trans, new_root);
499
500 ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
501 if (ret) {
502 /* We potentially lose an unused inode item here */
503 btrfs_abort_transaction(trans, root, ret);
504 goto fail;
505 }
506
507 /*
508 * insert the directory item
509 */
510 ret = btrfs_set_inode_index(dir, &index);
511 if (ret) {
512 btrfs_abort_transaction(trans, root, ret);
513 goto fail;
514 }
515
516 ret = btrfs_insert_dir_item(trans, root,
517 name, namelen, dir, &key,
518 BTRFS_FT_DIR, index);
519 if (ret) {
520 btrfs_abort_transaction(trans, root, ret);
521 goto fail;
522 }
523
524 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
525 ret = btrfs_update_inode(trans, root, dir);
526 BUG_ON(ret);
527
528 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
529 objectid, root->root_key.objectid,
530 btrfs_ino(dir), index, name, namelen);
531 BUG_ON(ret);
532
533 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
534 root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
535 objectid);
536 if (ret)
537 btrfs_abort_transaction(trans, root, ret);
538
539 fail:
540 trans->block_rsv = NULL;
541 trans->bytes_reserved = 0;
542 if (async_transid) {
543 *async_transid = trans->transid;
544 err = btrfs_commit_transaction_async(trans, root, 1);
545 if (err)
546 err = btrfs_commit_transaction(trans, root);
547 } else {
548 err = btrfs_commit_transaction(trans, root);
549 }
550 if (err && !ret)
551 ret = err;
552
553 if (!ret)
554 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
555 out:
556 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
557 return ret;
558 }
559
560 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
561 struct dentry *dentry, char *name, int namelen,
562 u64 *async_transid, bool readonly,
563 struct btrfs_qgroup_inherit *inherit)
564 {
565 struct inode *inode;
566 struct btrfs_pending_snapshot *pending_snapshot;
567 struct btrfs_trans_handle *trans;
568 int ret;
569
570 if (!root->ref_cows)
571 return -EINVAL;
572
573 ret = btrfs_start_delalloc_inodes(root, 0);
574 if (ret)
575 return ret;
576
577 btrfs_wait_ordered_extents(root);
578
579 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
580 if (!pending_snapshot)
581 return -ENOMEM;
582
583 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
584 BTRFS_BLOCK_RSV_TEMP);
585 /*
586 * 1 - parent dir inode
587 * 2 - dir entries
588 * 1 - root item
589 * 2 - root ref/backref
590 * 1 - root of snapshot
591 * 1 - UUID item
592 */
593 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
594 &pending_snapshot->block_rsv, 8,
595 &pending_snapshot->qgroup_reserved,
596 false);
597 if (ret)
598 goto out;
599
600 pending_snapshot->dentry = dentry;
601 pending_snapshot->root = root;
602 pending_snapshot->readonly = readonly;
603 pending_snapshot->dir = dir;
604 pending_snapshot->inherit = inherit;
605
606 trans = btrfs_start_transaction(root, 0);
607 if (IS_ERR(trans)) {
608 ret = PTR_ERR(trans);
609 goto fail;
610 }
611
612 spin_lock(&root->fs_info->trans_lock);
613 list_add(&pending_snapshot->list,
614 &trans->transaction->pending_snapshots);
615 spin_unlock(&root->fs_info->trans_lock);
616 if (async_transid) {
617 *async_transid = trans->transid;
618 ret = btrfs_commit_transaction_async(trans,
619 root->fs_info->extent_root, 1);
620 if (ret)
621 ret = btrfs_commit_transaction(trans, root);
622 } else {
623 ret = btrfs_commit_transaction(trans,
624 root->fs_info->extent_root);
625 }
626 if (ret)
627 goto fail;
628
629 ret = pending_snapshot->error;
630 if (ret)
631 goto fail;
632
633 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
634 if (ret)
635 goto fail;
636
637 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
638 if (IS_ERR(inode)) {
639 ret = PTR_ERR(inode);
640 goto fail;
641 }
642 BUG_ON(!inode);
643 d_instantiate(dentry, inode);
644 ret = 0;
645 fail:
646 btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
647 &pending_snapshot->block_rsv,
648 pending_snapshot->qgroup_reserved);
649 out:
650 kfree(pending_snapshot);
651 return ret;
652 }
653
654 /* copy of check_sticky in fs/namei.c()
655 * It's inline, so penalty for filesystems that don't use sticky bit is
656 * minimal.
657 */
658 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
659 {
660 kuid_t fsuid = current_fsuid();
661
662 if (!(dir->i_mode & S_ISVTX))
663 return 0;
664 if (uid_eq(inode->i_uid, fsuid))
665 return 0;
666 if (uid_eq(dir->i_uid, fsuid))
667 return 0;
668 return !capable(CAP_FOWNER);
669 }
670
671 /* copy of may_delete in fs/namei.c()
672 * Check whether we can remove a link victim from directory dir, check
673 * whether the type of victim is right.
674 * 1. We can't do it if dir is read-only (done in permission())
675 * 2. We should have write and exec permissions on dir
676 * 3. We can't remove anything from append-only dir
677 * 4. We can't do anything with immutable dir (done in permission())
678 * 5. If the sticky bit on dir is set we should either
679 * a. be owner of dir, or
680 * b. be owner of victim, or
681 * c. have CAP_FOWNER capability
682 * 6. If the victim is append-only or immutable we can't do antyhing with
683 * links pointing to it.
684 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
685 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
686 * 9. We can't remove a root or mountpoint.
687 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
688 * nfs_async_unlink().
689 */
690
691 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
692 {
693 int error;
694
695 if (!victim->d_inode)
696 return -ENOENT;
697
698 BUG_ON(victim->d_parent->d_inode != dir);
699 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
700
701 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
702 if (error)
703 return error;
704 if (IS_APPEND(dir))
705 return -EPERM;
706 if (btrfs_check_sticky(dir, victim->d_inode)||
707 IS_APPEND(victim->d_inode)||
708 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
709 return -EPERM;
710 if (isdir) {
711 if (!S_ISDIR(victim->d_inode->i_mode))
712 return -ENOTDIR;
713 if (IS_ROOT(victim))
714 return -EBUSY;
715 } else if (S_ISDIR(victim->d_inode->i_mode))
716 return -EISDIR;
717 if (IS_DEADDIR(dir))
718 return -ENOENT;
719 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
720 return -EBUSY;
721 return 0;
722 }
723
724 /* copy of may_create in fs/namei.c() */
725 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
726 {
727 if (child->d_inode)
728 return -EEXIST;
729 if (IS_DEADDIR(dir))
730 return -ENOENT;
731 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
732 }
733
734 /*
735 * Create a new subvolume below @parent. This is largely modeled after
736 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
737 * inside this filesystem so it's quite a bit simpler.
738 */
739 static noinline int btrfs_mksubvol(struct path *parent,
740 char *name, int namelen,
741 struct btrfs_root *snap_src,
742 u64 *async_transid, bool readonly,
743 struct btrfs_qgroup_inherit *inherit)
744 {
745 struct inode *dir = parent->dentry->d_inode;
746 struct dentry *dentry;
747 int error;
748
749 error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
750 if (error == -EINTR)
751 return error;
752
753 dentry = lookup_one_len(name, parent->dentry, namelen);
754 error = PTR_ERR(dentry);
755 if (IS_ERR(dentry))
756 goto out_unlock;
757
758 error = -EEXIST;
759 if (dentry->d_inode)
760 goto out_dput;
761
762 error = btrfs_may_create(dir, dentry);
763 if (error)
764 goto out_dput;
765
766 /*
767 * even if this name doesn't exist, we may get hash collisions.
768 * check for them now when we can safely fail
769 */
770 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
771 dir->i_ino, name,
772 namelen);
773 if (error)
774 goto out_dput;
775
776 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
777
778 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
779 goto out_up_read;
780
781 if (snap_src) {
782 error = create_snapshot(snap_src, dir, dentry, name, namelen,
783 async_transid, readonly, inherit);
784 } else {
785 error = create_subvol(dir, dentry, name, namelen,
786 async_transid, inherit);
787 }
788 if (!error)
789 fsnotify_mkdir(dir, dentry);
790 out_up_read:
791 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
792 out_dput:
793 dput(dentry);
794 out_unlock:
795 mutex_unlock(&dir->i_mutex);
796 return error;
797 }
798
799 /*
800 * When we're defragging a range, we don't want to kick it off again
801 * if it is really just waiting for delalloc to send it down.
802 * If we find a nice big extent or delalloc range for the bytes in the
803 * file you want to defrag, we return 0 to let you know to skip this
804 * part of the file
805 */
806 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
807 {
808 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
809 struct extent_map *em = NULL;
810 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
811 u64 end;
812
813 read_lock(&em_tree->lock);
814 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
815 read_unlock(&em_tree->lock);
816
817 if (em) {
818 end = extent_map_end(em);
819 free_extent_map(em);
820 if (end - offset > thresh)
821 return 0;
822 }
823 /* if we already have a nice delalloc here, just stop */
824 thresh /= 2;
825 end = count_range_bits(io_tree, &offset, offset + thresh,
826 thresh, EXTENT_DELALLOC, 1);
827 if (end >= thresh)
828 return 0;
829 return 1;
830 }
831
832 /*
833 * helper function to walk through a file and find extents
834 * newer than a specific transid, and smaller than thresh.
835 *
836 * This is used by the defragging code to find new and small
837 * extents
838 */
839 static int find_new_extents(struct btrfs_root *root,
840 struct inode *inode, u64 newer_than,
841 u64 *off, int thresh)
842 {
843 struct btrfs_path *path;
844 struct btrfs_key min_key;
845 struct btrfs_key max_key;
846 struct extent_buffer *leaf;
847 struct btrfs_file_extent_item *extent;
848 int type;
849 int ret;
850 u64 ino = btrfs_ino(inode);
851
852 path = btrfs_alloc_path();
853 if (!path)
854 return -ENOMEM;
855
856 min_key.objectid = ino;
857 min_key.type = BTRFS_EXTENT_DATA_KEY;
858 min_key.offset = *off;
859
860 max_key.objectid = ino;
861 max_key.type = (u8)-1;
862 max_key.offset = (u64)-1;
863
864 path->keep_locks = 1;
865
866 while(1) {
867 ret = btrfs_search_forward(root, &min_key, &max_key,
868 path, newer_than);
869 if (ret != 0)
870 goto none;
871 if (min_key.objectid != ino)
872 goto none;
873 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
874 goto none;
875
876 leaf = path->nodes[0];
877 extent = btrfs_item_ptr(leaf, path->slots[0],
878 struct btrfs_file_extent_item);
879
880 type = btrfs_file_extent_type(leaf, extent);
881 if (type == BTRFS_FILE_EXTENT_REG &&
882 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
883 check_defrag_in_cache(inode, min_key.offset, thresh)) {
884 *off = min_key.offset;
885 btrfs_free_path(path);
886 return 0;
887 }
888
889 if (min_key.offset == (u64)-1)
890 goto none;
891
892 min_key.offset++;
893 btrfs_release_path(path);
894 }
895 none:
896 btrfs_free_path(path);
897 return -ENOENT;
898 }
899
900 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
901 {
902 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
903 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
904 struct extent_map *em;
905 u64 len = PAGE_CACHE_SIZE;
906
907 /*
908 * hopefully we have this extent in the tree already, try without
909 * the full extent lock
910 */
911 read_lock(&em_tree->lock);
912 em = lookup_extent_mapping(em_tree, start, len);
913 read_unlock(&em_tree->lock);
914
915 if (!em) {
916 /* get the big lock and read metadata off disk */
917 lock_extent(io_tree, start, start + len - 1);
918 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
919 unlock_extent(io_tree, start, start + len - 1);
920
921 if (IS_ERR(em))
922 return NULL;
923 }
924
925 return em;
926 }
927
928 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
929 {
930 struct extent_map *next;
931 bool ret = true;
932
933 /* this is the last extent */
934 if (em->start + em->len >= i_size_read(inode))
935 return false;
936
937 next = defrag_lookup_extent(inode, em->start + em->len);
938 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
939 ret = false;
940
941 free_extent_map(next);
942 return ret;
943 }
944
945 static int should_defrag_range(struct inode *inode, u64 start, int thresh,
946 u64 *last_len, u64 *skip, u64 *defrag_end,
947 int compress)
948 {
949 struct extent_map *em;
950 int ret = 1;
951 bool next_mergeable = true;
952
953 /*
954 * make sure that once we start defragging an extent, we keep on
955 * defragging it
956 */
957 if (start < *defrag_end)
958 return 1;
959
960 *skip = 0;
961
962 em = defrag_lookup_extent(inode, start);
963 if (!em)
964 return 0;
965
966 /* this will cover holes, and inline extents */
967 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
968 ret = 0;
969 goto out;
970 }
971
972 next_mergeable = defrag_check_next_extent(inode, em);
973
974 /*
975 * we hit a real extent, if it is big or the next extent is not a
976 * real extent, don't bother defragging it
977 */
978 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
979 (em->len >= thresh || !next_mergeable))
980 ret = 0;
981 out:
982 /*
983 * last_len ends up being a counter of how many bytes we've defragged.
984 * every time we choose not to defrag an extent, we reset *last_len
985 * so that the next tiny extent will force a defrag.
986 *
987 * The end result of this is that tiny extents before a single big
988 * extent will force at least part of that big extent to be defragged.
989 */
990 if (ret) {
991 *defrag_end = extent_map_end(em);
992 } else {
993 *last_len = 0;
994 *skip = extent_map_end(em);
995 *defrag_end = 0;
996 }
997
998 free_extent_map(em);
999 return ret;
1000 }
1001
1002 /*
1003 * it doesn't do much good to defrag one or two pages
1004 * at a time. This pulls in a nice chunk of pages
1005 * to COW and defrag.
1006 *
1007 * It also makes sure the delalloc code has enough
1008 * dirty data to avoid making new small extents as part
1009 * of the defrag
1010 *
1011 * It's a good idea to start RA on this range
1012 * before calling this.
1013 */
1014 static int cluster_pages_for_defrag(struct inode *inode,
1015 struct page **pages,
1016 unsigned long start_index,
1017 int num_pages)
1018 {
1019 unsigned long file_end;
1020 u64 isize = i_size_read(inode);
1021 u64 page_start;
1022 u64 page_end;
1023 u64 page_cnt;
1024 int ret;
1025 int i;
1026 int i_done;
1027 struct btrfs_ordered_extent *ordered;
1028 struct extent_state *cached_state = NULL;
1029 struct extent_io_tree *tree;
1030 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1031
1032 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1033 if (!isize || start_index > file_end)
1034 return 0;
1035
1036 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1037
1038 ret = btrfs_delalloc_reserve_space(inode,
1039 page_cnt << PAGE_CACHE_SHIFT);
1040 if (ret)
1041 return ret;
1042 i_done = 0;
1043 tree = &BTRFS_I(inode)->io_tree;
1044
1045 /* step one, lock all the pages */
1046 for (i = 0; i < page_cnt; i++) {
1047 struct page *page;
1048 again:
1049 page = find_or_create_page(inode->i_mapping,
1050 start_index + i, mask);
1051 if (!page)
1052 break;
1053
1054 page_start = page_offset(page);
1055 page_end = page_start + PAGE_CACHE_SIZE - 1;
1056 while (1) {
1057 lock_extent(tree, page_start, page_end);
1058 ordered = btrfs_lookup_ordered_extent(inode,
1059 page_start);
1060 unlock_extent(tree, page_start, page_end);
1061 if (!ordered)
1062 break;
1063
1064 unlock_page(page);
1065 btrfs_start_ordered_extent(inode, ordered, 1);
1066 btrfs_put_ordered_extent(ordered);
1067 lock_page(page);
1068 /*
1069 * we unlocked the page above, so we need check if
1070 * it was released or not.
1071 */
1072 if (page->mapping != inode->i_mapping) {
1073 unlock_page(page);
1074 page_cache_release(page);
1075 goto again;
1076 }
1077 }
1078
1079 if (!PageUptodate(page)) {
1080 btrfs_readpage(NULL, page);
1081 lock_page(page);
1082 if (!PageUptodate(page)) {
1083 unlock_page(page);
1084 page_cache_release(page);
1085 ret = -EIO;
1086 break;
1087 }
1088 }
1089
1090 if (page->mapping != inode->i_mapping) {
1091 unlock_page(page);
1092 page_cache_release(page);
1093 goto again;
1094 }
1095
1096 pages[i] = page;
1097 i_done++;
1098 }
1099 if (!i_done || ret)
1100 goto out;
1101
1102 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1103 goto out;
1104
1105 /*
1106 * so now we have a nice long stream of locked
1107 * and up to date pages, lets wait on them
1108 */
1109 for (i = 0; i < i_done; i++)
1110 wait_on_page_writeback(pages[i]);
1111
1112 page_start = page_offset(pages[0]);
1113 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1114
1115 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1116 page_start, page_end - 1, 0, &cached_state);
1117 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1118 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1119 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1120 &cached_state, GFP_NOFS);
1121
1122 if (i_done != page_cnt) {
1123 spin_lock(&BTRFS_I(inode)->lock);
1124 BTRFS_I(inode)->outstanding_extents++;
1125 spin_unlock(&BTRFS_I(inode)->lock);
1126 btrfs_delalloc_release_space(inode,
1127 (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1128 }
1129
1130
1131 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1132 &cached_state, GFP_NOFS);
1133
1134 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1135 page_start, page_end - 1, &cached_state,
1136 GFP_NOFS);
1137
1138 for (i = 0; i < i_done; i++) {
1139 clear_page_dirty_for_io(pages[i]);
1140 ClearPageChecked(pages[i]);
1141 set_page_extent_mapped(pages[i]);
1142 set_page_dirty(pages[i]);
1143 unlock_page(pages[i]);
1144 page_cache_release(pages[i]);
1145 }
1146 return i_done;
1147 out:
1148 for (i = 0; i < i_done; i++) {
1149 unlock_page(pages[i]);
1150 page_cache_release(pages[i]);
1151 }
1152 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1153 return ret;
1154
1155 }
1156
1157 int btrfs_defrag_file(struct inode *inode, struct file *file,
1158 struct btrfs_ioctl_defrag_range_args *range,
1159 u64 newer_than, unsigned long max_to_defrag)
1160 {
1161 struct btrfs_root *root = BTRFS_I(inode)->root;
1162 struct file_ra_state *ra = NULL;
1163 unsigned long last_index;
1164 u64 isize = i_size_read(inode);
1165 u64 last_len = 0;
1166 u64 skip = 0;
1167 u64 defrag_end = 0;
1168 u64 newer_off = range->start;
1169 unsigned long i;
1170 unsigned long ra_index = 0;
1171 int ret;
1172 int defrag_count = 0;
1173 int compress_type = BTRFS_COMPRESS_ZLIB;
1174 int extent_thresh = range->extent_thresh;
1175 int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1176 int cluster = max_cluster;
1177 u64 new_align = ~((u64)128 * 1024 - 1);
1178 struct page **pages = NULL;
1179
1180 if (isize == 0)
1181 return 0;
1182
1183 if (range->start >= isize)
1184 return -EINVAL;
1185
1186 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1187 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1188 return -EINVAL;
1189 if (range->compress_type)
1190 compress_type = range->compress_type;
1191 }
1192
1193 if (extent_thresh == 0)
1194 extent_thresh = 256 * 1024;
1195
1196 /*
1197 * if we were not given a file, allocate a readahead
1198 * context
1199 */
1200 if (!file) {
1201 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1202 if (!ra)
1203 return -ENOMEM;
1204 file_ra_state_init(ra, inode->i_mapping);
1205 } else {
1206 ra = &file->f_ra;
1207 }
1208
1209 pages = kmalloc(sizeof(struct page *) * max_cluster,
1210 GFP_NOFS);
1211 if (!pages) {
1212 ret = -ENOMEM;
1213 goto out_ra;
1214 }
1215
1216 /* find the last page to defrag */
1217 if (range->start + range->len > range->start) {
1218 last_index = min_t(u64, isize - 1,
1219 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1220 } else {
1221 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1222 }
1223
1224 if (newer_than) {
1225 ret = find_new_extents(root, inode, newer_than,
1226 &newer_off, 64 * 1024);
1227 if (!ret) {
1228 range->start = newer_off;
1229 /*
1230 * we always align our defrag to help keep
1231 * the extents in the file evenly spaced
1232 */
1233 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1234 } else
1235 goto out_ra;
1236 } else {
1237 i = range->start >> PAGE_CACHE_SHIFT;
1238 }
1239 if (!max_to_defrag)
1240 max_to_defrag = last_index + 1;
1241
1242 /*
1243 * make writeback starts from i, so the defrag range can be
1244 * written sequentially.
1245 */
1246 if (i < inode->i_mapping->writeback_index)
1247 inode->i_mapping->writeback_index = i;
1248
1249 while (i <= last_index && defrag_count < max_to_defrag &&
1250 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1251 PAGE_CACHE_SHIFT)) {
1252 /*
1253 * make sure we stop running if someone unmounts
1254 * the FS
1255 */
1256 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1257 break;
1258
1259 if (btrfs_defrag_cancelled(root->fs_info)) {
1260 printk(KERN_DEBUG "btrfs: defrag_file cancelled\n");
1261 ret = -EAGAIN;
1262 break;
1263 }
1264
1265 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1266 extent_thresh, &last_len, &skip,
1267 &defrag_end, range->flags &
1268 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1269 unsigned long next;
1270 /*
1271 * the should_defrag function tells us how much to skip
1272 * bump our counter by the suggested amount
1273 */
1274 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1275 i = max(i + 1, next);
1276 continue;
1277 }
1278
1279 if (!newer_than) {
1280 cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1281 PAGE_CACHE_SHIFT) - i;
1282 cluster = min(cluster, max_cluster);
1283 } else {
1284 cluster = max_cluster;
1285 }
1286
1287 if (i + cluster > ra_index) {
1288 ra_index = max(i, ra_index);
1289 btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1290 cluster);
1291 ra_index += max_cluster;
1292 }
1293
1294 mutex_lock(&inode->i_mutex);
1295 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1296 BTRFS_I(inode)->force_compress = compress_type;
1297 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1298 if (ret < 0) {
1299 mutex_unlock(&inode->i_mutex);
1300 goto out_ra;
1301 }
1302
1303 defrag_count += ret;
1304 balance_dirty_pages_ratelimited(inode->i_mapping);
1305 mutex_unlock(&inode->i_mutex);
1306
1307 if (newer_than) {
1308 if (newer_off == (u64)-1)
1309 break;
1310
1311 if (ret > 0)
1312 i += ret;
1313
1314 newer_off = max(newer_off + 1,
1315 (u64)i << PAGE_CACHE_SHIFT);
1316
1317 ret = find_new_extents(root, inode,
1318 newer_than, &newer_off,
1319 64 * 1024);
1320 if (!ret) {
1321 range->start = newer_off;
1322 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1323 } else {
1324 break;
1325 }
1326 } else {
1327 if (ret > 0) {
1328 i += ret;
1329 last_len += ret << PAGE_CACHE_SHIFT;
1330 } else {
1331 i++;
1332 last_len = 0;
1333 }
1334 }
1335 }
1336
1337 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1338 filemap_flush(inode->i_mapping);
1339
1340 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1341 /* the filemap_flush will queue IO into the worker threads, but
1342 * we have to make sure the IO is actually started and that
1343 * ordered extents get created before we return
1344 */
1345 atomic_inc(&root->fs_info->async_submit_draining);
1346 while (atomic_read(&root->fs_info->nr_async_submits) ||
1347 atomic_read(&root->fs_info->async_delalloc_pages)) {
1348 wait_event(root->fs_info->async_submit_wait,
1349 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1350 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1351 }
1352 atomic_dec(&root->fs_info->async_submit_draining);
1353 }
1354
1355 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1356 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1357 }
1358
1359 ret = defrag_count;
1360
1361 out_ra:
1362 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1363 mutex_lock(&inode->i_mutex);
1364 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1365 mutex_unlock(&inode->i_mutex);
1366 }
1367 if (!file)
1368 kfree(ra);
1369 kfree(pages);
1370 return ret;
1371 }
1372
1373 static noinline int btrfs_ioctl_resize(struct file *file,
1374 void __user *arg)
1375 {
1376 u64 new_size;
1377 u64 old_size;
1378 u64 devid = 1;
1379 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
1380 struct btrfs_ioctl_vol_args *vol_args;
1381 struct btrfs_trans_handle *trans;
1382 struct btrfs_device *device = NULL;
1383 char *sizestr;
1384 char *devstr = NULL;
1385 int ret = 0;
1386 int mod = 0;
1387
1388 if (!capable(CAP_SYS_ADMIN))
1389 return -EPERM;
1390
1391 ret = mnt_want_write_file(file);
1392 if (ret)
1393 return ret;
1394
1395 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1396 1)) {
1397 mnt_drop_write_file(file);
1398 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1399 }
1400
1401 mutex_lock(&root->fs_info->volume_mutex);
1402 vol_args = memdup_user(arg, sizeof(*vol_args));
1403 if (IS_ERR(vol_args)) {
1404 ret = PTR_ERR(vol_args);
1405 goto out;
1406 }
1407
1408 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1409
1410 sizestr = vol_args->name;
1411 devstr = strchr(sizestr, ':');
1412 if (devstr) {
1413 char *end;
1414 sizestr = devstr + 1;
1415 *devstr = '\0';
1416 devstr = vol_args->name;
1417 devid = simple_strtoull(devstr, &end, 10);
1418 if (!devid) {
1419 ret = -EINVAL;
1420 goto out_free;
1421 }
1422 printk(KERN_INFO "btrfs: resizing devid %llu\n", devid);
1423 }
1424
1425 device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1426 if (!device) {
1427 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n",
1428 devid);
1429 ret = -ENODEV;
1430 goto out_free;
1431 }
1432
1433 if (!device->writeable) {
1434 printk(KERN_INFO "btrfs: resizer unable to apply on "
1435 "readonly device %llu\n",
1436 devid);
1437 ret = -EPERM;
1438 goto out_free;
1439 }
1440
1441 if (!strcmp(sizestr, "max"))
1442 new_size = device->bdev->bd_inode->i_size;
1443 else {
1444 if (sizestr[0] == '-') {
1445 mod = -1;
1446 sizestr++;
1447 } else if (sizestr[0] == '+') {
1448 mod = 1;
1449 sizestr++;
1450 }
1451 new_size = memparse(sizestr, NULL);
1452 if (new_size == 0) {
1453 ret = -EINVAL;
1454 goto out_free;
1455 }
1456 }
1457
1458 if (device->is_tgtdev_for_dev_replace) {
1459 ret = -EPERM;
1460 goto out_free;
1461 }
1462
1463 old_size = device->total_bytes;
1464
1465 if (mod < 0) {
1466 if (new_size > old_size) {
1467 ret = -EINVAL;
1468 goto out_free;
1469 }
1470 new_size = old_size - new_size;
1471 } else if (mod > 0) {
1472 new_size = old_size + new_size;
1473 }
1474
1475 if (new_size < 256 * 1024 * 1024) {
1476 ret = -EINVAL;
1477 goto out_free;
1478 }
1479 if (new_size > device->bdev->bd_inode->i_size) {
1480 ret = -EFBIG;
1481 goto out_free;
1482 }
1483
1484 do_div(new_size, root->sectorsize);
1485 new_size *= root->sectorsize;
1486
1487 printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n",
1488 rcu_str_deref(device->name), new_size);
1489
1490 if (new_size > old_size) {
1491 trans = btrfs_start_transaction(root, 0);
1492 if (IS_ERR(trans)) {
1493 ret = PTR_ERR(trans);
1494 goto out_free;
1495 }
1496 ret = btrfs_grow_device(trans, device, new_size);
1497 btrfs_commit_transaction(trans, root);
1498 } else if (new_size < old_size) {
1499 ret = btrfs_shrink_device(device, new_size);
1500 } /* equal, nothing need to do */
1501
1502 out_free:
1503 kfree(vol_args);
1504 out:
1505 mutex_unlock(&root->fs_info->volume_mutex);
1506 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1507 mnt_drop_write_file(file);
1508 return ret;
1509 }
1510
1511 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1512 char *name, unsigned long fd, int subvol,
1513 u64 *transid, bool readonly,
1514 struct btrfs_qgroup_inherit *inherit)
1515 {
1516 int namelen;
1517 int ret = 0;
1518
1519 ret = mnt_want_write_file(file);
1520 if (ret)
1521 goto out;
1522
1523 namelen = strlen(name);
1524 if (strchr(name, '/')) {
1525 ret = -EINVAL;
1526 goto out_drop_write;
1527 }
1528
1529 if (name[0] == '.' &&
1530 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1531 ret = -EEXIST;
1532 goto out_drop_write;
1533 }
1534
1535 if (subvol) {
1536 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1537 NULL, transid, readonly, inherit);
1538 } else {
1539 struct fd src = fdget(fd);
1540 struct inode *src_inode;
1541 if (!src.file) {
1542 ret = -EINVAL;
1543 goto out_drop_write;
1544 }
1545
1546 src_inode = file_inode(src.file);
1547 if (src_inode->i_sb != file_inode(file)->i_sb) {
1548 printk(KERN_INFO "btrfs: Snapshot src from "
1549 "another FS\n");
1550 ret = -EINVAL;
1551 } else {
1552 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1553 BTRFS_I(src_inode)->root,
1554 transid, readonly, inherit);
1555 }
1556 fdput(src);
1557 }
1558 out_drop_write:
1559 mnt_drop_write_file(file);
1560 out:
1561 return ret;
1562 }
1563
1564 static noinline int btrfs_ioctl_snap_create(struct file *file,
1565 void __user *arg, int subvol)
1566 {
1567 struct btrfs_ioctl_vol_args *vol_args;
1568 int ret;
1569
1570 vol_args = memdup_user(arg, sizeof(*vol_args));
1571 if (IS_ERR(vol_args))
1572 return PTR_ERR(vol_args);
1573 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1574
1575 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1576 vol_args->fd, subvol,
1577 NULL, false, NULL);
1578
1579 kfree(vol_args);
1580 return ret;
1581 }
1582
1583 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1584 void __user *arg, int subvol)
1585 {
1586 struct btrfs_ioctl_vol_args_v2 *vol_args;
1587 int ret;
1588 u64 transid = 0;
1589 u64 *ptr = NULL;
1590 bool readonly = false;
1591 struct btrfs_qgroup_inherit *inherit = NULL;
1592
1593 vol_args = memdup_user(arg, sizeof(*vol_args));
1594 if (IS_ERR(vol_args))
1595 return PTR_ERR(vol_args);
1596 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1597
1598 if (vol_args->flags &
1599 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1600 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1601 ret = -EOPNOTSUPP;
1602 goto out;
1603 }
1604
1605 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1606 ptr = &transid;
1607 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1608 readonly = true;
1609 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1610 if (vol_args->size > PAGE_CACHE_SIZE) {
1611 ret = -EINVAL;
1612 goto out;
1613 }
1614 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1615 if (IS_ERR(inherit)) {
1616 ret = PTR_ERR(inherit);
1617 goto out;
1618 }
1619 }
1620
1621 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1622 vol_args->fd, subvol, ptr,
1623 readonly, inherit);
1624
1625 if (ret == 0 && ptr &&
1626 copy_to_user(arg +
1627 offsetof(struct btrfs_ioctl_vol_args_v2,
1628 transid), ptr, sizeof(*ptr)))
1629 ret = -EFAULT;
1630 out:
1631 kfree(vol_args);
1632 kfree(inherit);
1633 return ret;
1634 }
1635
1636 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1637 void __user *arg)
1638 {
1639 struct inode *inode = file_inode(file);
1640 struct btrfs_root *root = BTRFS_I(inode)->root;
1641 int ret = 0;
1642 u64 flags = 0;
1643
1644 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1645 return -EINVAL;
1646
1647 down_read(&root->fs_info->subvol_sem);
1648 if (btrfs_root_readonly(root))
1649 flags |= BTRFS_SUBVOL_RDONLY;
1650 up_read(&root->fs_info->subvol_sem);
1651
1652 if (copy_to_user(arg, &flags, sizeof(flags)))
1653 ret = -EFAULT;
1654
1655 return ret;
1656 }
1657
1658 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1659 void __user *arg)
1660 {
1661 struct inode *inode = file_inode(file);
1662 struct btrfs_root *root = BTRFS_I(inode)->root;
1663 struct btrfs_trans_handle *trans;
1664 u64 root_flags;
1665 u64 flags;
1666 int ret = 0;
1667
1668 ret = mnt_want_write_file(file);
1669 if (ret)
1670 goto out;
1671
1672 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1673 ret = -EINVAL;
1674 goto out_drop_write;
1675 }
1676
1677 if (copy_from_user(&flags, arg, sizeof(flags))) {
1678 ret = -EFAULT;
1679 goto out_drop_write;
1680 }
1681
1682 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1683 ret = -EINVAL;
1684 goto out_drop_write;
1685 }
1686
1687 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1688 ret = -EOPNOTSUPP;
1689 goto out_drop_write;
1690 }
1691
1692 if (!inode_owner_or_capable(inode)) {
1693 ret = -EACCES;
1694 goto out_drop_write;
1695 }
1696
1697 down_write(&root->fs_info->subvol_sem);
1698
1699 /* nothing to do */
1700 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1701 goto out_drop_sem;
1702
1703 root_flags = btrfs_root_flags(&root->root_item);
1704 if (flags & BTRFS_SUBVOL_RDONLY)
1705 btrfs_set_root_flags(&root->root_item,
1706 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1707 else
1708 btrfs_set_root_flags(&root->root_item,
1709 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1710
1711 trans = btrfs_start_transaction(root, 1);
1712 if (IS_ERR(trans)) {
1713 ret = PTR_ERR(trans);
1714 goto out_reset;
1715 }
1716
1717 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1718 &root->root_key, &root->root_item);
1719
1720 btrfs_commit_transaction(trans, root);
1721 out_reset:
1722 if (ret)
1723 btrfs_set_root_flags(&root->root_item, root_flags);
1724 out_drop_sem:
1725 up_write(&root->fs_info->subvol_sem);
1726 out_drop_write:
1727 mnt_drop_write_file(file);
1728 out:
1729 return ret;
1730 }
1731
1732 /*
1733 * helper to check if the subvolume references other subvolumes
1734 */
1735 static noinline int may_destroy_subvol(struct btrfs_root *root)
1736 {
1737 struct btrfs_path *path;
1738 struct btrfs_dir_item *di;
1739 struct btrfs_key key;
1740 u64 dir_id;
1741 int ret;
1742
1743 path = btrfs_alloc_path();
1744 if (!path)
1745 return -ENOMEM;
1746
1747 /* Make sure this root isn't set as the default subvol */
1748 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
1749 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
1750 dir_id, "default", 7, 0);
1751 if (di && !IS_ERR(di)) {
1752 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1753 if (key.objectid == root->root_key.objectid) {
1754 ret = -ENOTEMPTY;
1755 goto out;
1756 }
1757 btrfs_release_path(path);
1758 }
1759
1760 key.objectid = root->root_key.objectid;
1761 key.type = BTRFS_ROOT_REF_KEY;
1762 key.offset = (u64)-1;
1763
1764 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1765 &key, path, 0, 0);
1766 if (ret < 0)
1767 goto out;
1768 BUG_ON(ret == 0);
1769
1770 ret = 0;
1771 if (path->slots[0] > 0) {
1772 path->slots[0]--;
1773 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1774 if (key.objectid == root->root_key.objectid &&
1775 key.type == BTRFS_ROOT_REF_KEY)
1776 ret = -ENOTEMPTY;
1777 }
1778 out:
1779 btrfs_free_path(path);
1780 return ret;
1781 }
1782
1783 static noinline int key_in_sk(struct btrfs_key *key,
1784 struct btrfs_ioctl_search_key *sk)
1785 {
1786 struct btrfs_key test;
1787 int ret;
1788
1789 test.objectid = sk->min_objectid;
1790 test.type = sk->min_type;
1791 test.offset = sk->min_offset;
1792
1793 ret = btrfs_comp_cpu_keys(key, &test);
1794 if (ret < 0)
1795 return 0;
1796
1797 test.objectid = sk->max_objectid;
1798 test.type = sk->max_type;
1799 test.offset = sk->max_offset;
1800
1801 ret = btrfs_comp_cpu_keys(key, &test);
1802 if (ret > 0)
1803 return 0;
1804 return 1;
1805 }
1806
1807 static noinline int copy_to_sk(struct btrfs_root *root,
1808 struct btrfs_path *path,
1809 struct btrfs_key *key,
1810 struct btrfs_ioctl_search_key *sk,
1811 char *buf,
1812 unsigned long *sk_offset,
1813 int *num_found)
1814 {
1815 u64 found_transid;
1816 struct extent_buffer *leaf;
1817 struct btrfs_ioctl_search_header sh;
1818 unsigned long item_off;
1819 unsigned long item_len;
1820 int nritems;
1821 int i;
1822 int slot;
1823 int ret = 0;
1824
1825 leaf = path->nodes[0];
1826 slot = path->slots[0];
1827 nritems = btrfs_header_nritems(leaf);
1828
1829 if (btrfs_header_generation(leaf) > sk->max_transid) {
1830 i = nritems;
1831 goto advance_key;
1832 }
1833 found_transid = btrfs_header_generation(leaf);
1834
1835 for (i = slot; i < nritems; i++) {
1836 item_off = btrfs_item_ptr_offset(leaf, i);
1837 item_len = btrfs_item_size_nr(leaf, i);
1838
1839 btrfs_item_key_to_cpu(leaf, key, i);
1840 if (!key_in_sk(key, sk))
1841 continue;
1842
1843 if (sizeof(sh) + item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1844 item_len = 0;
1845
1846 if (sizeof(sh) + item_len + *sk_offset >
1847 BTRFS_SEARCH_ARGS_BUFSIZE) {
1848 ret = 1;
1849 goto overflow;
1850 }
1851
1852 sh.objectid = key->objectid;
1853 sh.offset = key->offset;
1854 sh.type = key->type;
1855 sh.len = item_len;
1856 sh.transid = found_transid;
1857
1858 /* copy search result header */
1859 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1860 *sk_offset += sizeof(sh);
1861
1862 if (item_len) {
1863 char *p = buf + *sk_offset;
1864 /* copy the item */
1865 read_extent_buffer(leaf, p,
1866 item_off, item_len);
1867 *sk_offset += item_len;
1868 }
1869 (*num_found)++;
1870
1871 if (*num_found >= sk->nr_items)
1872 break;
1873 }
1874 advance_key:
1875 ret = 0;
1876 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1877 key->offset++;
1878 else if (key->type < (u8)-1 && key->type < sk->max_type) {
1879 key->offset = 0;
1880 key->type++;
1881 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1882 key->offset = 0;
1883 key->type = 0;
1884 key->objectid++;
1885 } else
1886 ret = 1;
1887 overflow:
1888 return ret;
1889 }
1890
1891 static noinline int search_ioctl(struct inode *inode,
1892 struct btrfs_ioctl_search_args *args)
1893 {
1894 struct btrfs_root *root;
1895 struct btrfs_key key;
1896 struct btrfs_key max_key;
1897 struct btrfs_path *path;
1898 struct btrfs_ioctl_search_key *sk = &args->key;
1899 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1900 int ret;
1901 int num_found = 0;
1902 unsigned long sk_offset = 0;
1903
1904 path = btrfs_alloc_path();
1905 if (!path)
1906 return -ENOMEM;
1907
1908 if (sk->tree_id == 0) {
1909 /* search the root of the inode that was passed */
1910 root = BTRFS_I(inode)->root;
1911 } else {
1912 key.objectid = sk->tree_id;
1913 key.type = BTRFS_ROOT_ITEM_KEY;
1914 key.offset = (u64)-1;
1915 root = btrfs_read_fs_root_no_name(info, &key);
1916 if (IS_ERR(root)) {
1917 printk(KERN_ERR "could not find root %llu\n",
1918 sk->tree_id);
1919 btrfs_free_path(path);
1920 return -ENOENT;
1921 }
1922 }
1923
1924 key.objectid = sk->min_objectid;
1925 key.type = sk->min_type;
1926 key.offset = sk->min_offset;
1927
1928 max_key.objectid = sk->max_objectid;
1929 max_key.type = sk->max_type;
1930 max_key.offset = sk->max_offset;
1931
1932 path->keep_locks = 1;
1933
1934 while(1) {
1935 ret = btrfs_search_forward(root, &key, &max_key, path,
1936 sk->min_transid);
1937 if (ret != 0) {
1938 if (ret > 0)
1939 ret = 0;
1940 goto err;
1941 }
1942 ret = copy_to_sk(root, path, &key, sk, args->buf,
1943 &sk_offset, &num_found);
1944 btrfs_release_path(path);
1945 if (ret || num_found >= sk->nr_items)
1946 break;
1947
1948 }
1949 ret = 0;
1950 err:
1951 sk->nr_items = num_found;
1952 btrfs_free_path(path);
1953 return ret;
1954 }
1955
1956 static noinline int btrfs_ioctl_tree_search(struct file *file,
1957 void __user *argp)
1958 {
1959 struct btrfs_ioctl_search_args *args;
1960 struct inode *inode;
1961 int ret;
1962
1963 if (!capable(CAP_SYS_ADMIN))
1964 return -EPERM;
1965
1966 args = memdup_user(argp, sizeof(*args));
1967 if (IS_ERR(args))
1968 return PTR_ERR(args);
1969
1970 inode = file_inode(file);
1971 ret = search_ioctl(inode, args);
1972 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1973 ret = -EFAULT;
1974 kfree(args);
1975 return ret;
1976 }
1977
1978 /*
1979 * Search INODE_REFs to identify path name of 'dirid' directory
1980 * in a 'tree_id' tree. and sets path name to 'name'.
1981 */
1982 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1983 u64 tree_id, u64 dirid, char *name)
1984 {
1985 struct btrfs_root *root;
1986 struct btrfs_key key;
1987 char *ptr;
1988 int ret = -1;
1989 int slot;
1990 int len;
1991 int total_len = 0;
1992 struct btrfs_inode_ref *iref;
1993 struct extent_buffer *l;
1994 struct btrfs_path *path;
1995
1996 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1997 name[0]='\0';
1998 return 0;
1999 }
2000
2001 path = btrfs_alloc_path();
2002 if (!path)
2003 return -ENOMEM;
2004
2005 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2006
2007 key.objectid = tree_id;
2008 key.type = BTRFS_ROOT_ITEM_KEY;
2009 key.offset = (u64)-1;
2010 root = btrfs_read_fs_root_no_name(info, &key);
2011 if (IS_ERR(root)) {
2012 printk(KERN_ERR "could not find root %llu\n", tree_id);
2013 ret = -ENOENT;
2014 goto out;
2015 }
2016
2017 key.objectid = dirid;
2018 key.type = BTRFS_INODE_REF_KEY;
2019 key.offset = (u64)-1;
2020
2021 while(1) {
2022 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2023 if (ret < 0)
2024 goto out;
2025 else if (ret > 0) {
2026 ret = btrfs_previous_item(root, path, dirid,
2027 BTRFS_INODE_REF_KEY);
2028 if (ret < 0)
2029 goto out;
2030 else if (ret > 0) {
2031 ret = -ENOENT;
2032 goto out;
2033 }
2034 }
2035
2036 l = path->nodes[0];
2037 slot = path->slots[0];
2038 btrfs_item_key_to_cpu(l, &key, slot);
2039
2040 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2041 len = btrfs_inode_ref_name_len(l, iref);
2042 ptr -= len + 1;
2043 total_len += len + 1;
2044 if (ptr < name) {
2045 ret = -ENAMETOOLONG;
2046 goto out;
2047 }
2048
2049 *(ptr + len) = '/';
2050 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
2051
2052 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2053 break;
2054
2055 btrfs_release_path(path);
2056 key.objectid = key.offset;
2057 key.offset = (u64)-1;
2058 dirid = key.objectid;
2059 }
2060 memmove(name, ptr, total_len);
2061 name[total_len]='\0';
2062 ret = 0;
2063 out:
2064 btrfs_free_path(path);
2065 return ret;
2066 }
2067
2068 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2069 void __user *argp)
2070 {
2071 struct btrfs_ioctl_ino_lookup_args *args;
2072 struct inode *inode;
2073 int ret;
2074
2075 if (!capable(CAP_SYS_ADMIN))
2076 return -EPERM;
2077
2078 args = memdup_user(argp, sizeof(*args));
2079 if (IS_ERR(args))
2080 return PTR_ERR(args);
2081
2082 inode = file_inode(file);
2083
2084 if (args->treeid == 0)
2085 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2086
2087 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2088 args->treeid, args->objectid,
2089 args->name);
2090
2091 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2092 ret = -EFAULT;
2093
2094 kfree(args);
2095 return ret;
2096 }
2097
2098 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2099 void __user *arg)
2100 {
2101 struct dentry *parent = fdentry(file);
2102 struct dentry *dentry;
2103 struct inode *dir = parent->d_inode;
2104 struct inode *inode;
2105 struct btrfs_root *root = BTRFS_I(dir)->root;
2106 struct btrfs_root *dest = NULL;
2107 struct btrfs_ioctl_vol_args *vol_args;
2108 struct btrfs_trans_handle *trans;
2109 struct btrfs_block_rsv block_rsv;
2110 u64 qgroup_reserved;
2111 int namelen;
2112 int ret;
2113 int err = 0;
2114
2115 vol_args = memdup_user(arg, sizeof(*vol_args));
2116 if (IS_ERR(vol_args))
2117 return PTR_ERR(vol_args);
2118
2119 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2120 namelen = strlen(vol_args->name);
2121 if (strchr(vol_args->name, '/') ||
2122 strncmp(vol_args->name, "..", namelen) == 0) {
2123 err = -EINVAL;
2124 goto out;
2125 }
2126
2127 err = mnt_want_write_file(file);
2128 if (err)
2129 goto out;
2130
2131 err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
2132 if (err == -EINTR)
2133 goto out;
2134 dentry = lookup_one_len(vol_args->name, parent, namelen);
2135 if (IS_ERR(dentry)) {
2136 err = PTR_ERR(dentry);
2137 goto out_unlock_dir;
2138 }
2139
2140 if (!dentry->d_inode) {
2141 err = -ENOENT;
2142 goto out_dput;
2143 }
2144
2145 inode = dentry->d_inode;
2146 dest = BTRFS_I(inode)->root;
2147 if (!capable(CAP_SYS_ADMIN)){
2148 /*
2149 * Regular user. Only allow this with a special mount
2150 * option, when the user has write+exec access to the
2151 * subvol root, and when rmdir(2) would have been
2152 * allowed.
2153 *
2154 * Note that this is _not_ check that the subvol is
2155 * empty or doesn't contain data that we wouldn't
2156 * otherwise be able to delete.
2157 *
2158 * Users who want to delete empty subvols should try
2159 * rmdir(2).
2160 */
2161 err = -EPERM;
2162 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2163 goto out_dput;
2164
2165 /*
2166 * Do not allow deletion if the parent dir is the same
2167 * as the dir to be deleted. That means the ioctl
2168 * must be called on the dentry referencing the root
2169 * of the subvol, not a random directory contained
2170 * within it.
2171 */
2172 err = -EINVAL;
2173 if (root == dest)
2174 goto out_dput;
2175
2176 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2177 if (err)
2178 goto out_dput;
2179 }
2180
2181 /* check if subvolume may be deleted by a user */
2182 err = btrfs_may_delete(dir, dentry, 1);
2183 if (err)
2184 goto out_dput;
2185
2186 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2187 err = -EINVAL;
2188 goto out_dput;
2189 }
2190
2191 mutex_lock(&inode->i_mutex);
2192 err = d_invalidate(dentry);
2193 if (err)
2194 goto out_unlock;
2195
2196 down_write(&root->fs_info->subvol_sem);
2197
2198 err = may_destroy_subvol(dest);
2199 if (err)
2200 goto out_up_write;
2201
2202 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2203 /*
2204 * One for dir inode, two for dir entries, two for root
2205 * ref/backref.
2206 */
2207 err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2208 5, &qgroup_reserved, true);
2209 if (err)
2210 goto out_up_write;
2211
2212 trans = btrfs_start_transaction(root, 0);
2213 if (IS_ERR(trans)) {
2214 err = PTR_ERR(trans);
2215 goto out_release;
2216 }
2217 trans->block_rsv = &block_rsv;
2218 trans->bytes_reserved = block_rsv.size;
2219
2220 ret = btrfs_unlink_subvol(trans, root, dir,
2221 dest->root_key.objectid,
2222 dentry->d_name.name,
2223 dentry->d_name.len);
2224 if (ret) {
2225 err = ret;
2226 btrfs_abort_transaction(trans, root, ret);
2227 goto out_end_trans;
2228 }
2229
2230 btrfs_record_root_in_trans(trans, dest);
2231
2232 memset(&dest->root_item.drop_progress, 0,
2233 sizeof(dest->root_item.drop_progress));
2234 dest->root_item.drop_level = 0;
2235 btrfs_set_root_refs(&dest->root_item, 0);
2236
2237 if (!xchg(&dest->orphan_item_inserted, 1)) {
2238 ret = btrfs_insert_orphan_item(trans,
2239 root->fs_info->tree_root,
2240 dest->root_key.objectid);
2241 if (ret) {
2242 btrfs_abort_transaction(trans, root, ret);
2243 err = ret;
2244 goto out_end_trans;
2245 }
2246 }
2247
2248 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2249 dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
2250 dest->root_key.objectid);
2251 if (ret && ret != -ENOENT) {
2252 btrfs_abort_transaction(trans, root, ret);
2253 err = ret;
2254 goto out_end_trans;
2255 }
2256 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
2257 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2258 dest->root_item.received_uuid,
2259 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
2260 dest->root_key.objectid);
2261 if (ret && ret != -ENOENT) {
2262 btrfs_abort_transaction(trans, root, ret);
2263 err = ret;
2264 goto out_end_trans;
2265 }
2266 }
2267
2268 out_end_trans:
2269 trans->block_rsv = NULL;
2270 trans->bytes_reserved = 0;
2271 ret = btrfs_end_transaction(trans, root);
2272 if (ret && !err)
2273 err = ret;
2274 inode->i_flags |= S_DEAD;
2275 out_release:
2276 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2277 out_up_write:
2278 up_write(&root->fs_info->subvol_sem);
2279 out_unlock:
2280 mutex_unlock(&inode->i_mutex);
2281 if (!err) {
2282 shrink_dcache_sb(root->fs_info->sb);
2283 btrfs_invalidate_inodes(dest);
2284 d_delete(dentry);
2285
2286 /* the last ref */
2287 if (dest->cache_inode) {
2288 iput(dest->cache_inode);
2289 dest->cache_inode = NULL;
2290 }
2291 }
2292 out_dput:
2293 dput(dentry);
2294 out_unlock_dir:
2295 mutex_unlock(&dir->i_mutex);
2296 mnt_drop_write_file(file);
2297 out:
2298 kfree(vol_args);
2299 return err;
2300 }
2301
2302 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2303 {
2304 struct inode *inode = file_inode(file);
2305 struct btrfs_root *root = BTRFS_I(inode)->root;
2306 struct btrfs_ioctl_defrag_range_args *range;
2307 int ret;
2308
2309 ret = mnt_want_write_file(file);
2310 if (ret)
2311 return ret;
2312
2313 if (btrfs_root_readonly(root)) {
2314 ret = -EROFS;
2315 goto out;
2316 }
2317
2318 switch (inode->i_mode & S_IFMT) {
2319 case S_IFDIR:
2320 if (!capable(CAP_SYS_ADMIN)) {
2321 ret = -EPERM;
2322 goto out;
2323 }
2324 ret = btrfs_defrag_root(root);
2325 if (ret)
2326 goto out;
2327 ret = btrfs_defrag_root(root->fs_info->extent_root);
2328 break;
2329 case S_IFREG:
2330 if (!(file->f_mode & FMODE_WRITE)) {
2331 ret = -EINVAL;
2332 goto out;
2333 }
2334
2335 range = kzalloc(sizeof(*range), GFP_KERNEL);
2336 if (!range) {
2337 ret = -ENOMEM;
2338 goto out;
2339 }
2340
2341 if (argp) {
2342 if (copy_from_user(range, argp,
2343 sizeof(*range))) {
2344 ret = -EFAULT;
2345 kfree(range);
2346 goto out;
2347 }
2348 /* compression requires us to start the IO */
2349 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2350 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2351 range->extent_thresh = (u32)-1;
2352 }
2353 } else {
2354 /* the rest are all set to zero by kzalloc */
2355 range->len = (u64)-1;
2356 }
2357 ret = btrfs_defrag_file(file_inode(file), file,
2358 range, 0, 0);
2359 if (ret > 0)
2360 ret = 0;
2361 kfree(range);
2362 break;
2363 default:
2364 ret = -EINVAL;
2365 }
2366 out:
2367 mnt_drop_write_file(file);
2368 return ret;
2369 }
2370
2371 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2372 {
2373 struct btrfs_ioctl_vol_args *vol_args;
2374 int ret;
2375
2376 if (!capable(CAP_SYS_ADMIN))
2377 return -EPERM;
2378
2379 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2380 1)) {
2381 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2382 }
2383
2384 mutex_lock(&root->fs_info->volume_mutex);
2385 vol_args = memdup_user(arg, sizeof(*vol_args));
2386 if (IS_ERR(vol_args)) {
2387 ret = PTR_ERR(vol_args);
2388 goto out;
2389 }
2390
2391 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2392 ret = btrfs_init_new_device(root, vol_args->name);
2393
2394 kfree(vol_args);
2395 out:
2396 mutex_unlock(&root->fs_info->volume_mutex);
2397 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2398 return ret;
2399 }
2400
2401 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2402 {
2403 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
2404 struct btrfs_ioctl_vol_args *vol_args;
2405 int ret;
2406
2407 if (!capable(CAP_SYS_ADMIN))
2408 return -EPERM;
2409
2410 ret = mnt_want_write_file(file);
2411 if (ret)
2412 return ret;
2413
2414 vol_args = memdup_user(arg, sizeof(*vol_args));
2415 if (IS_ERR(vol_args)) {
2416 ret = PTR_ERR(vol_args);
2417 goto out;
2418 }
2419
2420 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2421
2422 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2423 1)) {
2424 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2425 goto out;
2426 }
2427
2428 mutex_lock(&root->fs_info->volume_mutex);
2429 ret = btrfs_rm_device(root, vol_args->name);
2430 mutex_unlock(&root->fs_info->volume_mutex);
2431 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2432
2433 out:
2434 kfree(vol_args);
2435 mnt_drop_write_file(file);
2436 return ret;
2437 }
2438
2439 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2440 {
2441 struct btrfs_ioctl_fs_info_args *fi_args;
2442 struct btrfs_device *device;
2443 struct btrfs_device *next;
2444 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2445 int ret = 0;
2446
2447 if (!capable(CAP_SYS_ADMIN))
2448 return -EPERM;
2449
2450 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2451 if (!fi_args)
2452 return -ENOMEM;
2453
2454 mutex_lock(&fs_devices->device_list_mutex);
2455 fi_args->num_devices = fs_devices->num_devices;
2456 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2457
2458 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2459 if (device->devid > fi_args->max_id)
2460 fi_args->max_id = device->devid;
2461 }
2462 mutex_unlock(&fs_devices->device_list_mutex);
2463
2464 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2465 ret = -EFAULT;
2466
2467 kfree(fi_args);
2468 return ret;
2469 }
2470
2471 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2472 {
2473 struct btrfs_ioctl_dev_info_args *di_args;
2474 struct btrfs_device *dev;
2475 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2476 int ret = 0;
2477 char *s_uuid = NULL;
2478
2479 if (!capable(CAP_SYS_ADMIN))
2480 return -EPERM;
2481
2482 di_args = memdup_user(arg, sizeof(*di_args));
2483 if (IS_ERR(di_args))
2484 return PTR_ERR(di_args);
2485
2486 if (!btrfs_is_empty_uuid(di_args->uuid))
2487 s_uuid = di_args->uuid;
2488
2489 mutex_lock(&fs_devices->device_list_mutex);
2490 dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2491
2492 if (!dev) {
2493 ret = -ENODEV;
2494 goto out;
2495 }
2496
2497 di_args->devid = dev->devid;
2498 di_args->bytes_used = dev->bytes_used;
2499 di_args->total_bytes = dev->total_bytes;
2500 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2501 if (dev->name) {
2502 struct rcu_string *name;
2503
2504 rcu_read_lock();
2505 name = rcu_dereference(dev->name);
2506 strncpy(di_args->path, name->str, sizeof(di_args->path));
2507 rcu_read_unlock();
2508 di_args->path[sizeof(di_args->path) - 1] = 0;
2509 } else {
2510 di_args->path[0] = '\0';
2511 }
2512
2513 out:
2514 mutex_unlock(&fs_devices->device_list_mutex);
2515 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2516 ret = -EFAULT;
2517
2518 kfree(di_args);
2519 return ret;
2520 }
2521
2522 static struct page *extent_same_get_page(struct inode *inode, u64 off)
2523 {
2524 struct page *page;
2525 pgoff_t index;
2526 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
2527
2528 index = off >> PAGE_CACHE_SHIFT;
2529
2530 page = grab_cache_page(inode->i_mapping, index);
2531 if (!page)
2532 return NULL;
2533
2534 if (!PageUptodate(page)) {
2535 if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
2536 0))
2537 return NULL;
2538 lock_page(page);
2539 if (!PageUptodate(page)) {
2540 unlock_page(page);
2541 page_cache_release(page);
2542 return NULL;
2543 }
2544 }
2545 unlock_page(page);
2546
2547 return page;
2548 }
2549
2550 static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
2551 {
2552 /* do any pending delalloc/csum calc on src, one way or
2553 another, and lock file content */
2554 while (1) {
2555 struct btrfs_ordered_extent *ordered;
2556 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2557 ordered = btrfs_lookup_first_ordered_extent(inode,
2558 off + len - 1);
2559 if (!ordered &&
2560 !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2561 off + len - 1, EXTENT_DELALLOC, 0, NULL))
2562 break;
2563 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2564 if (ordered)
2565 btrfs_put_ordered_extent(ordered);
2566 btrfs_wait_ordered_range(inode, off, len);
2567 }
2568 }
2569
2570 static void btrfs_double_unlock(struct inode *inode1, u64 loff1,
2571 struct inode *inode2, u64 loff2, u64 len)
2572 {
2573 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
2574 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
2575
2576 mutex_unlock(&inode1->i_mutex);
2577 mutex_unlock(&inode2->i_mutex);
2578 }
2579
2580 static void btrfs_double_lock(struct inode *inode1, u64 loff1,
2581 struct inode *inode2, u64 loff2, u64 len)
2582 {
2583 if (inode1 < inode2) {
2584 swap(inode1, inode2);
2585 swap(loff1, loff2);
2586 }
2587
2588 mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
2589 lock_extent_range(inode1, loff1, len);
2590 if (inode1 != inode2) {
2591 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
2592 lock_extent_range(inode2, loff2, len);
2593 }
2594 }
2595
2596 static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
2597 u64 dst_loff, u64 len)
2598 {
2599 int ret = 0;
2600 struct page *src_page, *dst_page;
2601 unsigned int cmp_len = PAGE_CACHE_SIZE;
2602 void *addr, *dst_addr;
2603
2604 while (len) {
2605 if (len < PAGE_CACHE_SIZE)
2606 cmp_len = len;
2607
2608 src_page = extent_same_get_page(src, loff);
2609 if (!src_page)
2610 return -EINVAL;
2611 dst_page = extent_same_get_page(dst, dst_loff);
2612 if (!dst_page) {
2613 page_cache_release(src_page);
2614 return -EINVAL;
2615 }
2616 addr = kmap_atomic(src_page);
2617 dst_addr = kmap_atomic(dst_page);
2618
2619 flush_dcache_page(src_page);
2620 flush_dcache_page(dst_page);
2621
2622 if (memcmp(addr, dst_addr, cmp_len))
2623 ret = BTRFS_SAME_DATA_DIFFERS;
2624
2625 kunmap_atomic(addr);
2626 kunmap_atomic(dst_addr);
2627 page_cache_release(src_page);
2628 page_cache_release(dst_page);
2629
2630 if (ret)
2631 break;
2632
2633 loff += cmp_len;
2634 dst_loff += cmp_len;
2635 len -= cmp_len;
2636 }
2637
2638 return ret;
2639 }
2640
2641 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len)
2642 {
2643 u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
2644
2645 if (off + len > inode->i_size || off + len < off)
2646 return -EINVAL;
2647 /* Check that we are block aligned - btrfs_clone() requires this */
2648 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
2649 return -EINVAL;
2650
2651 return 0;
2652 }
2653
2654 static int btrfs_extent_same(struct inode *src, u64 loff, u64 len,
2655 struct inode *dst, u64 dst_loff)
2656 {
2657 int ret;
2658
2659 /*
2660 * btrfs_clone() can't handle extents in the same file
2661 * yet. Once that works, we can drop this check and replace it
2662 * with a check for the same inode, but overlapping extents.
2663 */
2664 if (src == dst)
2665 return -EINVAL;
2666
2667 btrfs_double_lock(src, loff, dst, dst_loff, len);
2668
2669 ret = extent_same_check_offsets(src, loff, len);
2670 if (ret)
2671 goto out_unlock;
2672
2673 ret = extent_same_check_offsets(dst, dst_loff, len);
2674 if (ret)
2675 goto out_unlock;
2676
2677 /* don't make the dst file partly checksummed */
2678 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2679 (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
2680 ret = -EINVAL;
2681 goto out_unlock;
2682 }
2683
2684 ret = btrfs_cmp_data(src, loff, dst, dst_loff, len);
2685 if (ret == 0)
2686 ret = btrfs_clone(src, dst, loff, len, len, dst_loff);
2687
2688 out_unlock:
2689 btrfs_double_unlock(src, loff, dst, dst_loff, len);
2690
2691 return ret;
2692 }
2693
2694 #define BTRFS_MAX_DEDUPE_LEN (16 * 1024 * 1024)
2695
2696 static long btrfs_ioctl_file_extent_same(struct file *file,
2697 void __user *argp)
2698 {
2699 struct btrfs_ioctl_same_args tmp;
2700 struct btrfs_ioctl_same_args *same;
2701 struct btrfs_ioctl_same_extent_info *info;
2702 struct inode *src = file->f_dentry->d_inode;
2703 struct file *dst_file = NULL;
2704 struct inode *dst;
2705 u64 off;
2706 u64 len;
2707 int i;
2708 int ret;
2709 unsigned long size;
2710 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
2711 bool is_admin = capable(CAP_SYS_ADMIN);
2712
2713 if (!(file->f_mode & FMODE_READ))
2714 return -EINVAL;
2715
2716 ret = mnt_want_write_file(file);
2717 if (ret)
2718 return ret;
2719
2720 if (copy_from_user(&tmp,
2721 (struct btrfs_ioctl_same_args __user *)argp,
2722 sizeof(tmp))) {
2723 ret = -EFAULT;
2724 goto out;
2725 }
2726
2727 size = sizeof(tmp) +
2728 tmp.dest_count * sizeof(struct btrfs_ioctl_same_extent_info);
2729
2730 same = kmalloc(size, GFP_NOFS);
2731 if (!same) {
2732 ret = -EFAULT;
2733 goto out;
2734 }
2735
2736 if (copy_from_user(same,
2737 (struct btrfs_ioctl_same_args __user *)argp, size)) {
2738 ret = -EFAULT;
2739 goto out;
2740 }
2741
2742 off = same->logical_offset;
2743 len = same->length;
2744
2745 /*
2746 * Limit the total length we will dedupe for each operation.
2747 * This is intended to bound the total time spent in this
2748 * ioctl to something sane.
2749 */
2750 if (len > BTRFS_MAX_DEDUPE_LEN)
2751 len = BTRFS_MAX_DEDUPE_LEN;
2752
2753 if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
2754 /*
2755 * Btrfs does not support blocksize < page_size. As a
2756 * result, btrfs_cmp_data() won't correctly handle
2757 * this situation without an update.
2758 */
2759 ret = -EINVAL;
2760 goto out;
2761 }
2762
2763 ret = -EISDIR;
2764 if (S_ISDIR(src->i_mode))
2765 goto out;
2766
2767 ret = -EACCES;
2768 if (!S_ISREG(src->i_mode))
2769 goto out;
2770
2771 /* pre-format output fields to sane values */
2772 for (i = 0; i < same->dest_count; i++) {
2773 same->info[i].bytes_deduped = 0ULL;
2774 same->info[i].status = 0;
2775 }
2776
2777 ret = 0;
2778 for (i = 0; i < same->dest_count; i++) {
2779 info = &same->info[i];
2780
2781 dst_file = fget(info->fd);
2782 if (!dst_file) {
2783 info->status = -EBADF;
2784 goto next;
2785 }
2786
2787 if (!(is_admin || (dst_file->f_mode & FMODE_WRITE))) {
2788 info->status = -EINVAL;
2789 goto next;
2790 }
2791
2792 info->status = -EXDEV;
2793 if (file->f_path.mnt != dst_file->f_path.mnt)
2794 goto next;
2795
2796 dst = dst_file->f_dentry->d_inode;
2797 if (src->i_sb != dst->i_sb)
2798 goto next;
2799
2800 if (S_ISDIR(dst->i_mode)) {
2801 info->status = -EISDIR;
2802 goto next;
2803 }
2804
2805 if (!S_ISREG(dst->i_mode)) {
2806 info->status = -EACCES;
2807 goto next;
2808 }
2809
2810 info->status = btrfs_extent_same(src, off, len, dst,
2811 info->logical_offset);
2812 if (info->status == 0)
2813 info->bytes_deduped += len;
2814
2815 next:
2816 if (dst_file)
2817 fput(dst_file);
2818 }
2819
2820 ret = copy_to_user(argp, same, size);
2821 if (ret)
2822 ret = -EFAULT;
2823
2824 out:
2825 mnt_drop_write_file(file);
2826 return ret;
2827 }
2828
2829 /**
2830 * btrfs_clone() - clone a range from inode file to another
2831 *
2832 * @src: Inode to clone from
2833 * @inode: Inode to clone to
2834 * @off: Offset within source to start clone from
2835 * @olen: Original length, passed by user, of range to clone
2836 * @olen_aligned: Block-aligned value of olen, extent_same uses
2837 * identical values here
2838 * @destoff: Offset within @inode to start clone
2839 */
2840 static int btrfs_clone(struct inode *src, struct inode *inode,
2841 u64 off, u64 olen, u64 olen_aligned, u64 destoff)
2842 {
2843 struct btrfs_root *root = BTRFS_I(inode)->root;
2844 struct btrfs_path *path = NULL;
2845 struct extent_buffer *leaf;
2846 struct btrfs_trans_handle *trans;
2847 char *buf = NULL;
2848 struct btrfs_key key;
2849 u32 nritems;
2850 int slot;
2851 int ret;
2852 u64 len = olen_aligned;
2853
2854 ret = -ENOMEM;
2855 buf = vmalloc(btrfs_level_size(root, 0));
2856 if (!buf)
2857 return ret;
2858
2859 path = btrfs_alloc_path();
2860 if (!path) {
2861 vfree(buf);
2862 return ret;
2863 }
2864
2865 path->reada = 2;
2866 /* clone data */
2867 key.objectid = btrfs_ino(src);
2868 key.type = BTRFS_EXTENT_DATA_KEY;
2869 key.offset = 0;
2870
2871 while (1) {
2872 /*
2873 * note the key will change type as we walk through the
2874 * tree.
2875 */
2876 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
2877 0, 0);
2878 if (ret < 0)
2879 goto out;
2880
2881 nritems = btrfs_header_nritems(path->nodes[0]);
2882 if (path->slots[0] >= nritems) {
2883 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
2884 if (ret < 0)
2885 goto out;
2886 if (ret > 0)
2887 break;
2888 nritems = btrfs_header_nritems(path->nodes[0]);
2889 }
2890 leaf = path->nodes[0];
2891 slot = path->slots[0];
2892
2893 btrfs_item_key_to_cpu(leaf, &key, slot);
2894 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2895 key.objectid != btrfs_ino(src))
2896 break;
2897
2898 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2899 struct btrfs_file_extent_item *extent;
2900 int type;
2901 u32 size;
2902 struct btrfs_key new_key;
2903 u64 disko = 0, diskl = 0;
2904 u64 datao = 0, datal = 0;
2905 u8 comp;
2906 u64 endoff;
2907
2908 size = btrfs_item_size_nr(leaf, slot);
2909 read_extent_buffer(leaf, buf,
2910 btrfs_item_ptr_offset(leaf, slot),
2911 size);
2912
2913 extent = btrfs_item_ptr(leaf, slot,
2914 struct btrfs_file_extent_item);
2915 comp = btrfs_file_extent_compression(leaf, extent);
2916 type = btrfs_file_extent_type(leaf, extent);
2917 if (type == BTRFS_FILE_EXTENT_REG ||
2918 type == BTRFS_FILE_EXTENT_PREALLOC) {
2919 disko = btrfs_file_extent_disk_bytenr(leaf,
2920 extent);
2921 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2922 extent);
2923 datao = btrfs_file_extent_offset(leaf, extent);
2924 datal = btrfs_file_extent_num_bytes(leaf,
2925 extent);
2926 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2927 /* take upper bound, may be compressed */
2928 datal = btrfs_file_extent_ram_bytes(leaf,
2929 extent);
2930 }
2931 btrfs_release_path(path);
2932
2933 if (key.offset + datal <= off ||
2934 key.offset >= off + len - 1)
2935 goto next;
2936
2937 memcpy(&new_key, &key, sizeof(new_key));
2938 new_key.objectid = btrfs_ino(inode);
2939 if (off <= key.offset)
2940 new_key.offset = key.offset + destoff - off;
2941 else
2942 new_key.offset = destoff;
2943
2944 /*
2945 * 1 - adjusting old extent (we may have to split it)
2946 * 1 - add new extent
2947 * 1 - inode update
2948 */
2949 trans = btrfs_start_transaction(root, 3);
2950 if (IS_ERR(trans)) {
2951 ret = PTR_ERR(trans);
2952 goto out;
2953 }
2954
2955 if (type == BTRFS_FILE_EXTENT_REG ||
2956 type == BTRFS_FILE_EXTENT_PREALLOC) {
2957 /*
2958 * a | --- range to clone ---| b
2959 * | ------------- extent ------------- |
2960 */
2961
2962 /* substract range b */
2963 if (key.offset + datal > off + len)
2964 datal = off + len - key.offset;
2965
2966 /* substract range a */
2967 if (off > key.offset) {
2968 datao += off - key.offset;
2969 datal -= off - key.offset;
2970 }
2971
2972 ret = btrfs_drop_extents(trans, root, inode,
2973 new_key.offset,
2974 new_key.offset + datal,
2975 1);
2976 if (ret) {
2977 btrfs_abort_transaction(trans, root,
2978 ret);
2979 btrfs_end_transaction(trans, root);
2980 goto out;
2981 }
2982
2983 ret = btrfs_insert_empty_item(trans, root, path,
2984 &new_key, size);
2985 if (ret) {
2986 btrfs_abort_transaction(trans, root,
2987 ret);
2988 btrfs_end_transaction(trans, root);
2989 goto out;
2990 }
2991
2992 leaf = path->nodes[0];
2993 slot = path->slots[0];
2994 write_extent_buffer(leaf, buf,
2995 btrfs_item_ptr_offset(leaf, slot),
2996 size);
2997
2998 extent = btrfs_item_ptr(leaf, slot,
2999 struct btrfs_file_extent_item);
3000
3001 /* disko == 0 means it's a hole */
3002 if (!disko)
3003 datao = 0;
3004
3005 btrfs_set_file_extent_offset(leaf, extent,
3006 datao);
3007 btrfs_set_file_extent_num_bytes(leaf, extent,
3008 datal);
3009 if (disko) {
3010 inode_add_bytes(inode, datal);
3011 ret = btrfs_inc_extent_ref(trans, root,
3012 disko, diskl, 0,
3013 root->root_key.objectid,
3014 btrfs_ino(inode),
3015 new_key.offset - datao,
3016 0);
3017 if (ret) {
3018 btrfs_abort_transaction(trans,
3019 root,
3020 ret);
3021 btrfs_end_transaction(trans,
3022 root);
3023 goto out;
3024
3025 }
3026 }
3027 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3028 u64 skip = 0;
3029 u64 trim = 0;
3030 if (off > key.offset) {
3031 skip = off - key.offset;
3032 new_key.offset += skip;
3033 }
3034
3035 if (key.offset + datal > off + len)
3036 trim = key.offset + datal - (off + len);
3037
3038 if (comp && (skip || trim)) {
3039 ret = -EINVAL;
3040 btrfs_end_transaction(trans, root);
3041 goto out;
3042 }
3043 size -= skip + trim;
3044 datal -= skip + trim;
3045
3046 ret = btrfs_drop_extents(trans, root, inode,
3047 new_key.offset,
3048 new_key.offset + datal,
3049 1);
3050 if (ret) {
3051 btrfs_abort_transaction(trans, root,
3052 ret);
3053 btrfs_end_transaction(trans, root);
3054 goto out;
3055 }
3056
3057 ret = btrfs_insert_empty_item(trans, root, path,
3058 &new_key, size);
3059 if (ret) {
3060 btrfs_abort_transaction(trans, root,
3061 ret);
3062 btrfs_end_transaction(trans, root);
3063 goto out;
3064 }
3065
3066 if (skip) {
3067 u32 start =
3068 btrfs_file_extent_calc_inline_size(0);
3069 memmove(buf+start, buf+start+skip,
3070 datal);
3071 }
3072
3073 leaf = path->nodes[0];
3074 slot = path->slots[0];
3075 write_extent_buffer(leaf, buf,
3076 btrfs_item_ptr_offset(leaf, slot),
3077 size);
3078 inode_add_bytes(inode, datal);
3079 }
3080
3081 btrfs_mark_buffer_dirty(leaf);
3082 btrfs_release_path(path);
3083
3084 inode_inc_iversion(inode);
3085 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3086
3087 /*
3088 * we round up to the block size at eof when
3089 * determining which extents to clone above,
3090 * but shouldn't round up the file size
3091 */
3092 endoff = new_key.offset + datal;
3093 if (endoff > destoff+olen)
3094 endoff = destoff+olen;
3095 if (endoff > inode->i_size)
3096 btrfs_i_size_write(inode, endoff);
3097
3098 ret = btrfs_update_inode(trans, root, inode);
3099 if (ret) {
3100 btrfs_abort_transaction(trans, root, ret);
3101 btrfs_end_transaction(trans, root);
3102 goto out;
3103 }
3104 ret = btrfs_end_transaction(trans, root);
3105 }
3106 next:
3107 btrfs_release_path(path);
3108 key.offset++;
3109 }
3110 ret = 0;
3111
3112 out:
3113 btrfs_release_path(path);
3114 btrfs_free_path(path);
3115 vfree(buf);
3116 return ret;
3117 }
3118
3119 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
3120 u64 off, u64 olen, u64 destoff)
3121 {
3122 struct inode *inode = fdentry(file)->d_inode;
3123 struct btrfs_root *root = BTRFS_I(inode)->root;
3124 struct fd src_file;
3125 struct inode *src;
3126 int ret;
3127 u64 len = olen;
3128 u64 bs = root->fs_info->sb->s_blocksize;
3129 int same_inode = 0;
3130
3131 /*
3132 * TODO:
3133 * - split compressed inline extents. annoying: we need to
3134 * decompress into destination's address_space (the file offset
3135 * may change, so source mapping won't do), then recompress (or
3136 * otherwise reinsert) a subrange.
3137 * - allow ranges within the same file to be cloned (provided
3138 * they don't overlap)?
3139 */
3140
3141 /* the destination must be opened for writing */
3142 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
3143 return -EINVAL;
3144
3145 if (btrfs_root_readonly(root))
3146 return -EROFS;
3147
3148 ret = mnt_want_write_file(file);
3149 if (ret)
3150 return ret;
3151
3152 src_file = fdget(srcfd);
3153 if (!src_file.file) {
3154 ret = -EBADF;
3155 goto out_drop_write;
3156 }
3157
3158 ret = -EXDEV;
3159 if (src_file.file->f_path.mnt != file->f_path.mnt)
3160 goto out_fput;
3161
3162 src = file_inode(src_file.file);
3163
3164 ret = -EINVAL;
3165 if (src == inode)
3166 same_inode = 1;
3167
3168 /* the src must be open for reading */
3169 if (!(src_file.file->f_mode & FMODE_READ))
3170 goto out_fput;
3171
3172 /* don't make the dst file partly checksummed */
3173 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3174 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3175 goto out_fput;
3176
3177 ret = -EISDIR;
3178 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3179 goto out_fput;
3180
3181 ret = -EXDEV;
3182 if (src->i_sb != inode->i_sb)
3183 goto out_fput;
3184
3185 if (!same_inode) {
3186 if (inode < src) {
3187 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
3188 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
3189 } else {
3190 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
3191 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
3192 }
3193 } else {
3194 mutex_lock(&src->i_mutex);
3195 }
3196
3197 /* determine range to clone */
3198 ret = -EINVAL;
3199 if (off + len > src->i_size || off + len < off)
3200 goto out_unlock;
3201 if (len == 0)
3202 olen = len = src->i_size - off;
3203 /* if we extend to eof, continue to block boundary */
3204 if (off + len == src->i_size)
3205 len = ALIGN(src->i_size, bs) - off;
3206
3207 /* verify the end result is block aligned */
3208 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
3209 !IS_ALIGNED(destoff, bs))
3210 goto out_unlock;
3211
3212 /* verify if ranges are overlapped within the same file */
3213 if (same_inode) {
3214 if (destoff + len > off && destoff < off + len)
3215 goto out_unlock;
3216 }
3217
3218 if (destoff > inode->i_size) {
3219 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3220 if (ret)
3221 goto out_unlock;
3222 }
3223
3224 /* truncate page cache pages from target inode range */
3225 truncate_inode_pages_range(&inode->i_data, destoff,
3226 PAGE_CACHE_ALIGN(destoff + len) - 1);
3227
3228 lock_extent_range(src, off, len);
3229
3230 ret = btrfs_clone(src, inode, off, olen, len, destoff);
3231
3232 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
3233 out_unlock:
3234 mutex_unlock(&src->i_mutex);
3235 if (!same_inode)
3236 mutex_unlock(&inode->i_mutex);
3237 out_fput:
3238 fdput(src_file);
3239 out_drop_write:
3240 mnt_drop_write_file(file);
3241 return ret;
3242 }
3243
3244 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3245 {
3246 struct btrfs_ioctl_clone_range_args args;
3247
3248 if (copy_from_user(&args, argp, sizeof(args)))
3249 return -EFAULT;
3250 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
3251 args.src_length, args.dest_offset);
3252 }
3253
3254 /*
3255 * there are many ways the trans_start and trans_end ioctls can lead
3256 * to deadlocks. They should only be used by applications that
3257 * basically own the machine, and have a very in depth understanding
3258 * of all the possible deadlocks and enospc problems.
3259 */
3260 static long btrfs_ioctl_trans_start(struct file *file)
3261 {
3262 struct inode *inode = file_inode(file);
3263 struct btrfs_root *root = BTRFS_I(inode)->root;
3264 struct btrfs_trans_handle *trans;
3265 int ret;
3266
3267 ret = -EPERM;
3268 if (!capable(CAP_SYS_ADMIN))
3269 goto out;
3270
3271 ret = -EINPROGRESS;
3272 if (file->private_data)
3273 goto out;
3274
3275 ret = -EROFS;
3276 if (btrfs_root_readonly(root))
3277 goto out;
3278
3279 ret = mnt_want_write_file(file);
3280 if (ret)
3281 goto out;
3282
3283 atomic_inc(&root->fs_info->open_ioctl_trans);
3284
3285 ret = -ENOMEM;
3286 trans = btrfs_start_ioctl_transaction(root);
3287 if (IS_ERR(trans))
3288 goto out_drop;
3289
3290 file->private_data = trans;
3291 return 0;
3292
3293 out_drop:
3294 atomic_dec(&root->fs_info->open_ioctl_trans);
3295 mnt_drop_write_file(file);
3296 out:
3297 return ret;
3298 }
3299
3300 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3301 {
3302 struct inode *inode = file_inode(file);
3303 struct btrfs_root *root = BTRFS_I(inode)->root;
3304 struct btrfs_root *new_root;
3305 struct btrfs_dir_item *di;
3306 struct btrfs_trans_handle *trans;
3307 struct btrfs_path *path;
3308 struct btrfs_key location;
3309 struct btrfs_disk_key disk_key;
3310 u64 objectid = 0;
3311 u64 dir_id;
3312 int ret;
3313
3314 if (!capable(CAP_SYS_ADMIN))
3315 return -EPERM;
3316
3317 ret = mnt_want_write_file(file);
3318 if (ret)
3319 return ret;
3320
3321 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3322 ret = -EFAULT;
3323 goto out;
3324 }
3325
3326 if (!objectid)
3327 objectid = BTRFS_FS_TREE_OBJECTID;
3328
3329 location.objectid = objectid;
3330 location.type = BTRFS_ROOT_ITEM_KEY;
3331 location.offset = (u64)-1;
3332
3333 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
3334 if (IS_ERR(new_root)) {
3335 ret = PTR_ERR(new_root);
3336 goto out;
3337 }
3338
3339 path = btrfs_alloc_path();
3340 if (!path) {
3341 ret = -ENOMEM;
3342 goto out;
3343 }
3344 path->leave_spinning = 1;
3345
3346 trans = btrfs_start_transaction(root, 1);
3347 if (IS_ERR(trans)) {
3348 btrfs_free_path(path);
3349 ret = PTR_ERR(trans);
3350 goto out;
3351 }
3352
3353 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3354 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
3355 dir_id, "default", 7, 1);
3356 if (IS_ERR_OR_NULL(di)) {
3357 btrfs_free_path(path);
3358 btrfs_end_transaction(trans, root);
3359 printk(KERN_ERR "Umm, you don't have the default dir item, "
3360 "this isn't going to work\n");
3361 ret = -ENOENT;
3362 goto out;
3363 }
3364
3365 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3366 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3367 btrfs_mark_buffer_dirty(path->nodes[0]);
3368 btrfs_free_path(path);
3369
3370 btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
3371 btrfs_end_transaction(trans, root);
3372 out:
3373 mnt_drop_write_file(file);
3374 return ret;
3375 }
3376
3377 void btrfs_get_block_group_info(struct list_head *groups_list,
3378 struct btrfs_ioctl_space_info *space)
3379 {
3380 struct btrfs_block_group_cache *block_group;
3381
3382 space->total_bytes = 0;
3383 space->used_bytes = 0;
3384 space->flags = 0;
3385 list_for_each_entry(block_group, groups_list, list) {
3386 space->flags = block_group->flags;
3387 space->total_bytes += block_group->key.offset;
3388 space->used_bytes +=
3389 btrfs_block_group_used(&block_group->item);
3390 }
3391 }
3392
3393 static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
3394 {
3395 struct btrfs_ioctl_space_args space_args;
3396 struct btrfs_ioctl_space_info space;
3397 struct btrfs_ioctl_space_info *dest;
3398 struct btrfs_ioctl_space_info *dest_orig;
3399 struct btrfs_ioctl_space_info __user *user_dest;
3400 struct btrfs_space_info *info;
3401 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3402 BTRFS_BLOCK_GROUP_SYSTEM,
3403 BTRFS_BLOCK_GROUP_METADATA,
3404 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3405 int num_types = 4;
3406 int alloc_size;
3407 int ret = 0;
3408 u64 slot_count = 0;
3409 int i, c;
3410
3411 if (copy_from_user(&space_args,
3412 (struct btrfs_ioctl_space_args __user *)arg,
3413 sizeof(space_args)))
3414 return -EFAULT;
3415
3416 for (i = 0; i < num_types; i++) {
3417 struct btrfs_space_info *tmp;
3418
3419 info = NULL;
3420 rcu_read_lock();
3421 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3422 list) {
3423 if (tmp->flags == types[i]) {
3424 info = tmp;
3425 break;
3426 }
3427 }
3428 rcu_read_unlock();
3429
3430 if (!info)
3431 continue;
3432
3433 down_read(&info->groups_sem);
3434 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3435 if (!list_empty(&info->block_groups[c]))
3436 slot_count++;
3437 }
3438 up_read(&info->groups_sem);
3439 }
3440
3441 /* space_slots == 0 means they are asking for a count */
3442 if (space_args.space_slots == 0) {
3443 space_args.total_spaces = slot_count;
3444 goto out;
3445 }
3446
3447 slot_count = min_t(u64, space_args.space_slots, slot_count);
3448
3449 alloc_size = sizeof(*dest) * slot_count;
3450
3451 /* we generally have at most 6 or so space infos, one for each raid
3452 * level. So, a whole page should be more than enough for everyone
3453 */
3454 if (alloc_size > PAGE_CACHE_SIZE)
3455 return -ENOMEM;
3456
3457 space_args.total_spaces = 0;
3458 dest = kmalloc(alloc_size, GFP_NOFS);
3459 if (!dest)
3460 return -ENOMEM;
3461 dest_orig = dest;
3462
3463 /* now we have a buffer to copy into */
3464 for (i = 0; i < num_types; i++) {
3465 struct btrfs_space_info *tmp;
3466
3467 if (!slot_count)
3468 break;
3469
3470 info = NULL;
3471 rcu_read_lock();
3472 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3473 list) {
3474 if (tmp->flags == types[i]) {
3475 info = tmp;
3476 break;
3477 }
3478 }
3479 rcu_read_unlock();
3480
3481 if (!info)
3482 continue;
3483 down_read(&info->groups_sem);
3484 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3485 if (!list_empty(&info->block_groups[c])) {
3486 btrfs_get_block_group_info(
3487 &info->block_groups[c], &space);
3488 memcpy(dest, &space, sizeof(space));
3489 dest++;
3490 space_args.total_spaces++;
3491 slot_count--;
3492 }
3493 if (!slot_count)
3494 break;
3495 }
3496 up_read(&info->groups_sem);
3497 }
3498
3499 user_dest = (struct btrfs_ioctl_space_info __user *)
3500 (arg + sizeof(struct btrfs_ioctl_space_args));
3501
3502 if (copy_to_user(user_dest, dest_orig, alloc_size))
3503 ret = -EFAULT;
3504
3505 kfree(dest_orig);
3506 out:
3507 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
3508 ret = -EFAULT;
3509
3510 return ret;
3511 }
3512
3513 /*
3514 * there are many ways the trans_start and trans_end ioctls can lead
3515 * to deadlocks. They should only be used by applications that
3516 * basically own the machine, and have a very in depth understanding
3517 * of all the possible deadlocks and enospc problems.
3518 */
3519 long btrfs_ioctl_trans_end(struct file *file)
3520 {
3521 struct inode *inode = file_inode(file);
3522 struct btrfs_root *root = BTRFS_I(inode)->root;
3523 struct btrfs_trans_handle *trans;
3524
3525 trans = file->private_data;
3526 if (!trans)
3527 return -EINVAL;
3528 file->private_data = NULL;
3529
3530 btrfs_end_transaction(trans, root);
3531
3532 atomic_dec(&root->fs_info->open_ioctl_trans);
3533
3534 mnt_drop_write_file(file);
3535 return 0;
3536 }
3537
3538 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
3539 void __user *argp)
3540 {
3541 struct btrfs_trans_handle *trans;
3542 u64 transid;
3543 int ret;
3544
3545 trans = btrfs_attach_transaction_barrier(root);
3546 if (IS_ERR(trans)) {
3547 if (PTR_ERR(trans) != -ENOENT)
3548 return PTR_ERR(trans);
3549
3550 /* No running transaction, don't bother */
3551 transid = root->fs_info->last_trans_committed;
3552 goto out;
3553 }
3554 transid = trans->transid;
3555 ret = btrfs_commit_transaction_async(trans, root, 0);
3556 if (ret) {
3557 btrfs_end_transaction(trans, root);
3558 return ret;
3559 }
3560 out:
3561 if (argp)
3562 if (copy_to_user(argp, &transid, sizeof(transid)))
3563 return -EFAULT;
3564 return 0;
3565 }
3566
3567 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
3568 void __user *argp)
3569 {
3570 u64 transid;
3571
3572 if (argp) {
3573 if (copy_from_user(&transid, argp, sizeof(transid)))
3574 return -EFAULT;
3575 } else {
3576 transid = 0; /* current trans */
3577 }
3578 return btrfs_wait_for_commit(root, transid);
3579 }
3580
3581 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
3582 {
3583 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3584 struct btrfs_ioctl_scrub_args *sa;
3585 int ret;
3586
3587 if (!capable(CAP_SYS_ADMIN))
3588 return -EPERM;
3589
3590 sa = memdup_user(arg, sizeof(*sa));
3591 if (IS_ERR(sa))
3592 return PTR_ERR(sa);
3593
3594 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
3595 ret = mnt_want_write_file(file);
3596 if (ret)
3597 goto out;
3598 }
3599
3600 ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
3601 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
3602 0);
3603
3604 if (copy_to_user(arg, sa, sizeof(*sa)))
3605 ret = -EFAULT;
3606
3607 if (!(sa->flags & BTRFS_SCRUB_READONLY))
3608 mnt_drop_write_file(file);
3609 out:
3610 kfree(sa);
3611 return ret;
3612 }
3613
3614 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
3615 {
3616 if (!capable(CAP_SYS_ADMIN))
3617 return -EPERM;
3618
3619 return btrfs_scrub_cancel(root->fs_info);
3620 }
3621
3622 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
3623 void __user *arg)
3624 {
3625 struct btrfs_ioctl_scrub_args *sa;
3626 int ret;
3627
3628 if (!capable(CAP_SYS_ADMIN))
3629 return -EPERM;
3630
3631 sa = memdup_user(arg, sizeof(*sa));
3632 if (IS_ERR(sa))
3633 return PTR_ERR(sa);
3634
3635 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
3636
3637 if (copy_to_user(arg, sa, sizeof(*sa)))
3638 ret = -EFAULT;
3639
3640 kfree(sa);
3641 return ret;
3642 }
3643
3644 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
3645 void __user *arg)
3646 {
3647 struct btrfs_ioctl_get_dev_stats *sa;
3648 int ret;
3649
3650 sa = memdup_user(arg, sizeof(*sa));
3651 if (IS_ERR(sa))
3652 return PTR_ERR(sa);
3653
3654 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3655 kfree(sa);
3656 return -EPERM;
3657 }
3658
3659 ret = btrfs_get_dev_stats(root, sa);
3660
3661 if (copy_to_user(arg, sa, sizeof(*sa)))
3662 ret = -EFAULT;
3663
3664 kfree(sa);
3665 return ret;
3666 }
3667
3668 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
3669 {
3670 struct btrfs_ioctl_dev_replace_args *p;
3671 int ret;
3672
3673 if (!capable(CAP_SYS_ADMIN))
3674 return -EPERM;
3675
3676 p = memdup_user(arg, sizeof(*p));
3677 if (IS_ERR(p))
3678 return PTR_ERR(p);
3679
3680 switch (p->cmd) {
3681 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3682 if (root->fs_info->sb->s_flags & MS_RDONLY)
3683 return -EROFS;
3684
3685 if (atomic_xchg(
3686 &root->fs_info->mutually_exclusive_operation_running,
3687 1)) {
3688 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3689 } else {
3690 ret = btrfs_dev_replace_start(root, p);
3691 atomic_set(
3692 &root->fs_info->mutually_exclusive_operation_running,
3693 0);
3694 }
3695 break;
3696 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
3697 btrfs_dev_replace_status(root->fs_info, p);
3698 ret = 0;
3699 break;
3700 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
3701 ret = btrfs_dev_replace_cancel(root->fs_info, p);
3702 break;
3703 default:
3704 ret = -EINVAL;
3705 break;
3706 }
3707
3708 if (copy_to_user(arg, p, sizeof(*p)))
3709 ret = -EFAULT;
3710
3711 kfree(p);
3712 return ret;
3713 }
3714
3715 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3716 {
3717 int ret = 0;
3718 int i;
3719 u64 rel_ptr;
3720 int size;
3721 struct btrfs_ioctl_ino_path_args *ipa = NULL;
3722 struct inode_fs_paths *ipath = NULL;
3723 struct btrfs_path *path;
3724
3725 if (!capable(CAP_DAC_READ_SEARCH))
3726 return -EPERM;
3727
3728 path = btrfs_alloc_path();
3729 if (!path) {
3730 ret = -ENOMEM;
3731 goto out;
3732 }
3733
3734 ipa = memdup_user(arg, sizeof(*ipa));
3735 if (IS_ERR(ipa)) {
3736 ret = PTR_ERR(ipa);
3737 ipa = NULL;
3738 goto out;
3739 }
3740
3741 size = min_t(u32, ipa->size, 4096);
3742 ipath = init_ipath(size, root, path);
3743 if (IS_ERR(ipath)) {
3744 ret = PTR_ERR(ipath);
3745 ipath = NULL;
3746 goto out;
3747 }
3748
3749 ret = paths_from_inode(ipa->inum, ipath);
3750 if (ret < 0)
3751 goto out;
3752
3753 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3754 rel_ptr = ipath->fspath->val[i] -
3755 (u64)(unsigned long)ipath->fspath->val;
3756 ipath->fspath->val[i] = rel_ptr;
3757 }
3758
3759 ret = copy_to_user((void *)(unsigned long)ipa->fspath,
3760 (void *)(unsigned long)ipath->fspath, size);
3761 if (ret) {
3762 ret = -EFAULT;
3763 goto out;
3764 }
3765
3766 out:
3767 btrfs_free_path(path);
3768 free_ipath(ipath);
3769 kfree(ipa);
3770
3771 return ret;
3772 }
3773
3774 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3775 {
3776 struct btrfs_data_container *inodes = ctx;
3777 const size_t c = 3 * sizeof(u64);
3778
3779 if (inodes->bytes_left >= c) {
3780 inodes->bytes_left -= c;
3781 inodes->val[inodes->elem_cnt] = inum;
3782 inodes->val[inodes->elem_cnt + 1] = offset;
3783 inodes->val[inodes->elem_cnt + 2] = root;
3784 inodes->elem_cnt += 3;
3785 } else {
3786 inodes->bytes_missing += c - inodes->bytes_left;
3787 inodes->bytes_left = 0;
3788 inodes->elem_missed += 3;
3789 }
3790
3791 return 0;
3792 }
3793
3794 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
3795 void __user *arg)
3796 {
3797 int ret = 0;
3798 int size;
3799 struct btrfs_ioctl_logical_ino_args *loi;
3800 struct btrfs_data_container *inodes = NULL;
3801 struct btrfs_path *path = NULL;
3802
3803 if (!capable(CAP_SYS_ADMIN))
3804 return -EPERM;
3805
3806 loi = memdup_user(arg, sizeof(*loi));
3807 if (IS_ERR(loi)) {
3808 ret = PTR_ERR(loi);
3809 loi = NULL;
3810 goto out;
3811 }
3812
3813 path = btrfs_alloc_path();
3814 if (!path) {
3815 ret = -ENOMEM;
3816 goto out;
3817 }
3818
3819 size = min_t(u32, loi->size, 64 * 1024);
3820 inodes = init_data_container(size);
3821 if (IS_ERR(inodes)) {
3822 ret = PTR_ERR(inodes);
3823 inodes = NULL;
3824 goto out;
3825 }
3826
3827 ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
3828 build_ino_list, inodes);
3829 if (ret == -EINVAL)
3830 ret = -ENOENT;
3831 if (ret < 0)
3832 goto out;
3833
3834 ret = copy_to_user((void *)(unsigned long)loi->inodes,
3835 (void *)(unsigned long)inodes, size);
3836 if (ret)
3837 ret = -EFAULT;
3838
3839 out:
3840 btrfs_free_path(path);
3841 vfree(inodes);
3842 kfree(loi);
3843
3844 return ret;
3845 }
3846
3847 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
3848 struct btrfs_ioctl_balance_args *bargs)
3849 {
3850 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3851
3852 bargs->flags = bctl->flags;
3853
3854 if (atomic_read(&fs_info->balance_running))
3855 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3856 if (atomic_read(&fs_info->balance_pause_req))
3857 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3858 if (atomic_read(&fs_info->balance_cancel_req))
3859 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3860
3861 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3862 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3863 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3864
3865 if (lock) {
3866 spin_lock(&fs_info->balance_lock);
3867 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3868 spin_unlock(&fs_info->balance_lock);
3869 } else {
3870 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3871 }
3872 }
3873
3874 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
3875 {
3876 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3877 struct btrfs_fs_info *fs_info = root->fs_info;
3878 struct btrfs_ioctl_balance_args *bargs;
3879 struct btrfs_balance_control *bctl;
3880 bool need_unlock; /* for mut. excl. ops lock */
3881 int ret;
3882
3883 if (!capable(CAP_SYS_ADMIN))
3884 return -EPERM;
3885
3886 ret = mnt_want_write_file(file);
3887 if (ret)
3888 return ret;
3889
3890 again:
3891 if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
3892 mutex_lock(&fs_info->volume_mutex);
3893 mutex_lock(&fs_info->balance_mutex);
3894 need_unlock = true;
3895 goto locked;
3896 }
3897
3898 /*
3899 * mut. excl. ops lock is locked. Three possibilites:
3900 * (1) some other op is running
3901 * (2) balance is running
3902 * (3) balance is paused -- special case (think resume)
3903 */
3904 mutex_lock(&fs_info->balance_mutex);
3905 if (fs_info->balance_ctl) {
3906 /* this is either (2) or (3) */
3907 if (!atomic_read(&fs_info->balance_running)) {
3908 mutex_unlock(&fs_info->balance_mutex);
3909 if (!mutex_trylock(&fs_info->volume_mutex))
3910 goto again;
3911 mutex_lock(&fs_info->balance_mutex);
3912
3913 if (fs_info->balance_ctl &&
3914 !atomic_read(&fs_info->balance_running)) {
3915 /* this is (3) */
3916 need_unlock = false;
3917 goto locked;
3918 }
3919
3920 mutex_unlock(&fs_info->balance_mutex);
3921 mutex_unlock(&fs_info->volume_mutex);
3922 goto again;
3923 } else {
3924 /* this is (2) */
3925 mutex_unlock(&fs_info->balance_mutex);
3926 ret = -EINPROGRESS;
3927 goto out;
3928 }
3929 } else {
3930 /* this is (1) */
3931 mutex_unlock(&fs_info->balance_mutex);
3932 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3933 goto out;
3934 }
3935
3936 locked:
3937 BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
3938
3939 if (arg) {
3940 bargs = memdup_user(arg, sizeof(*bargs));
3941 if (IS_ERR(bargs)) {
3942 ret = PTR_ERR(bargs);
3943 goto out_unlock;
3944 }
3945
3946 if (bargs->flags & BTRFS_BALANCE_RESUME) {
3947 if (!fs_info->balance_ctl) {
3948 ret = -ENOTCONN;
3949 goto out_bargs;
3950 }
3951
3952 bctl = fs_info->balance_ctl;
3953 spin_lock(&fs_info->balance_lock);
3954 bctl->flags |= BTRFS_BALANCE_RESUME;
3955 spin_unlock(&fs_info->balance_lock);
3956
3957 goto do_balance;
3958 }
3959 } else {
3960 bargs = NULL;
3961 }
3962
3963 if (fs_info->balance_ctl) {
3964 ret = -EINPROGRESS;
3965 goto out_bargs;
3966 }
3967
3968 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3969 if (!bctl) {
3970 ret = -ENOMEM;
3971 goto out_bargs;
3972 }
3973
3974 bctl->fs_info = fs_info;
3975 if (arg) {
3976 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
3977 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
3978 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
3979
3980 bctl->flags = bargs->flags;
3981 } else {
3982 /* balance everything - no filters */
3983 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
3984 }
3985
3986 do_balance:
3987 /*
3988 * Ownership of bctl and mutually_exclusive_operation_running
3989 * goes to to btrfs_balance. bctl is freed in __cancel_balance,
3990 * or, if restriper was paused all the way until unmount, in
3991 * free_fs_info. mutually_exclusive_operation_running is
3992 * cleared in __cancel_balance.
3993 */
3994 need_unlock = false;
3995
3996 ret = btrfs_balance(bctl, bargs);
3997
3998 if (arg) {
3999 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4000 ret = -EFAULT;
4001 }
4002
4003 out_bargs:
4004 kfree(bargs);
4005 out_unlock:
4006 mutex_unlock(&fs_info->balance_mutex);
4007 mutex_unlock(&fs_info->volume_mutex);
4008 if (need_unlock)
4009 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
4010 out:
4011 mnt_drop_write_file(file);
4012 return ret;
4013 }
4014
4015 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
4016 {
4017 if (!capable(CAP_SYS_ADMIN))
4018 return -EPERM;
4019
4020 switch (cmd) {
4021 case BTRFS_BALANCE_CTL_PAUSE:
4022 return btrfs_pause_balance(root->fs_info);
4023 case BTRFS_BALANCE_CTL_CANCEL:
4024 return btrfs_cancel_balance(root->fs_info);
4025 }
4026
4027 return -EINVAL;
4028 }
4029
4030 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
4031 void __user *arg)
4032 {
4033 struct btrfs_fs_info *fs_info = root->fs_info;
4034 struct btrfs_ioctl_balance_args *bargs;
4035 int ret = 0;
4036
4037 if (!capable(CAP_SYS_ADMIN))
4038 return -EPERM;
4039
4040 mutex_lock(&fs_info->balance_mutex);
4041 if (!fs_info->balance_ctl) {
4042 ret = -ENOTCONN;
4043 goto out;
4044 }
4045
4046 bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
4047 if (!bargs) {
4048 ret = -ENOMEM;
4049 goto out;
4050 }
4051
4052 update_ioctl_balance_args(fs_info, 1, bargs);
4053
4054 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4055 ret = -EFAULT;
4056
4057 kfree(bargs);
4058 out:
4059 mutex_unlock(&fs_info->balance_mutex);
4060 return ret;
4061 }
4062
4063 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4064 {
4065 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4066 struct btrfs_ioctl_quota_ctl_args *sa;
4067 struct btrfs_trans_handle *trans = NULL;
4068 int ret;
4069 int err;
4070
4071 if (!capable(CAP_SYS_ADMIN))
4072 return -EPERM;
4073
4074 ret = mnt_want_write_file(file);
4075 if (ret)
4076 return ret;
4077
4078 sa = memdup_user(arg, sizeof(*sa));
4079 if (IS_ERR(sa)) {
4080 ret = PTR_ERR(sa);
4081 goto drop_write;
4082 }
4083
4084 down_write(&root->fs_info->subvol_sem);
4085 trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
4086 if (IS_ERR(trans)) {
4087 ret = PTR_ERR(trans);
4088 goto out;
4089 }
4090
4091 switch (sa->cmd) {
4092 case BTRFS_QUOTA_CTL_ENABLE:
4093 ret = btrfs_quota_enable(trans, root->fs_info);
4094 break;
4095 case BTRFS_QUOTA_CTL_DISABLE:
4096 ret = btrfs_quota_disable(trans, root->fs_info);
4097 break;
4098 default:
4099 ret = -EINVAL;
4100 break;
4101 }
4102
4103 err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
4104 if (err && !ret)
4105 ret = err;
4106 out:
4107 kfree(sa);
4108 up_write(&root->fs_info->subvol_sem);
4109 drop_write:
4110 mnt_drop_write_file(file);
4111 return ret;
4112 }
4113
4114 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4115 {
4116 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4117 struct btrfs_ioctl_qgroup_assign_args *sa;
4118 struct btrfs_trans_handle *trans;
4119 int ret;
4120 int err;
4121
4122 if (!capable(CAP_SYS_ADMIN))
4123 return -EPERM;
4124
4125 ret = mnt_want_write_file(file);
4126 if (ret)
4127 return ret;
4128
4129 sa = memdup_user(arg, sizeof(*sa));
4130 if (IS_ERR(sa)) {
4131 ret = PTR_ERR(sa);
4132 goto drop_write;
4133 }
4134
4135 trans = btrfs_join_transaction(root);
4136 if (IS_ERR(trans)) {
4137 ret = PTR_ERR(trans);
4138 goto out;
4139 }
4140
4141 /* FIXME: check if the IDs really exist */
4142 if (sa->assign) {
4143 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
4144 sa->src, sa->dst);
4145 } else {
4146 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
4147 sa->src, sa->dst);
4148 }
4149
4150 err = btrfs_end_transaction(trans, root);
4151 if (err && !ret)
4152 ret = err;
4153
4154 out:
4155 kfree(sa);
4156 drop_write:
4157 mnt_drop_write_file(file);
4158 return ret;
4159 }
4160
4161 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4162 {
4163 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4164 struct btrfs_ioctl_qgroup_create_args *sa;
4165 struct btrfs_trans_handle *trans;
4166 int ret;
4167 int err;
4168
4169 if (!capable(CAP_SYS_ADMIN))
4170 return -EPERM;
4171
4172 ret = mnt_want_write_file(file);
4173 if (ret)
4174 return ret;
4175
4176 sa = memdup_user(arg, sizeof(*sa));
4177 if (IS_ERR(sa)) {
4178 ret = PTR_ERR(sa);
4179 goto drop_write;
4180 }
4181
4182 if (!sa->qgroupid) {
4183 ret = -EINVAL;
4184 goto out;
4185 }
4186
4187 trans = btrfs_join_transaction(root);
4188 if (IS_ERR(trans)) {
4189 ret = PTR_ERR(trans);
4190 goto out;
4191 }
4192
4193 /* FIXME: check if the IDs really exist */
4194 if (sa->create) {
4195 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
4196 NULL);
4197 } else {
4198 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
4199 }
4200
4201 err = btrfs_end_transaction(trans, root);
4202 if (err && !ret)
4203 ret = err;
4204
4205 out:
4206 kfree(sa);
4207 drop_write:
4208 mnt_drop_write_file(file);
4209 return ret;
4210 }
4211
4212 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4213 {
4214 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4215 struct btrfs_ioctl_qgroup_limit_args *sa;
4216 struct btrfs_trans_handle *trans;
4217 int ret;
4218 int err;
4219 u64 qgroupid;
4220
4221 if (!capable(CAP_SYS_ADMIN))
4222 return -EPERM;
4223
4224 ret = mnt_want_write_file(file);
4225 if (ret)
4226 return ret;
4227
4228 sa = memdup_user(arg, sizeof(*sa));
4229 if (IS_ERR(sa)) {
4230 ret = PTR_ERR(sa);
4231 goto drop_write;
4232 }
4233
4234 trans = btrfs_join_transaction(root);
4235 if (IS_ERR(trans)) {
4236 ret = PTR_ERR(trans);
4237 goto out;
4238 }
4239
4240 qgroupid = sa->qgroupid;
4241 if (!qgroupid) {
4242 /* take the current subvol as qgroup */
4243 qgroupid = root->root_key.objectid;
4244 }
4245
4246 /* FIXME: check if the IDs really exist */
4247 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
4248
4249 err = btrfs_end_transaction(trans, root);
4250 if (err && !ret)
4251 ret = err;
4252
4253 out:
4254 kfree(sa);
4255 drop_write:
4256 mnt_drop_write_file(file);
4257 return ret;
4258 }
4259
4260 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4261 {
4262 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4263 struct btrfs_ioctl_quota_rescan_args *qsa;
4264 int ret;
4265
4266 if (!capable(CAP_SYS_ADMIN))
4267 return -EPERM;
4268
4269 ret = mnt_want_write_file(file);
4270 if (ret)
4271 return ret;
4272
4273 qsa = memdup_user(arg, sizeof(*qsa));
4274 if (IS_ERR(qsa)) {
4275 ret = PTR_ERR(qsa);
4276 goto drop_write;
4277 }
4278
4279 if (qsa->flags) {
4280 ret = -EINVAL;
4281 goto out;
4282 }
4283
4284 ret = btrfs_qgroup_rescan(root->fs_info);
4285
4286 out:
4287 kfree(qsa);
4288 drop_write:
4289 mnt_drop_write_file(file);
4290 return ret;
4291 }
4292
4293 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
4294 {
4295 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4296 struct btrfs_ioctl_quota_rescan_args *qsa;
4297 int ret = 0;
4298
4299 if (!capable(CAP_SYS_ADMIN))
4300 return -EPERM;
4301
4302 qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
4303 if (!qsa)
4304 return -ENOMEM;
4305
4306 if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4307 qsa->flags = 1;
4308 qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
4309 }
4310
4311 if (copy_to_user(arg, qsa, sizeof(*qsa)))
4312 ret = -EFAULT;
4313
4314 kfree(qsa);
4315 return ret;
4316 }
4317
4318 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
4319 {
4320 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
4321
4322 if (!capable(CAP_SYS_ADMIN))
4323 return -EPERM;
4324
4325 return btrfs_qgroup_wait_for_completion(root->fs_info);
4326 }
4327
4328 static long btrfs_ioctl_set_received_subvol(struct file *file,
4329 void __user *arg)
4330 {
4331 struct btrfs_ioctl_received_subvol_args *sa = NULL;
4332 struct inode *inode = file_inode(file);
4333 struct btrfs_root *root = BTRFS_I(inode)->root;
4334 struct btrfs_root_item *root_item = &root->root_item;
4335 struct btrfs_trans_handle *trans;
4336 struct timespec ct = CURRENT_TIME;
4337 int ret = 0;
4338 int received_uuid_changed;
4339
4340 ret = mnt_want_write_file(file);
4341 if (ret < 0)
4342 return ret;
4343
4344 down_write(&root->fs_info->subvol_sem);
4345
4346 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
4347 ret = -EINVAL;
4348 goto out;
4349 }
4350
4351 if (btrfs_root_readonly(root)) {
4352 ret = -EROFS;
4353 goto out;
4354 }
4355
4356 if (!inode_owner_or_capable(inode)) {
4357 ret = -EACCES;
4358 goto out;
4359 }
4360
4361 sa = memdup_user(arg, sizeof(*sa));
4362 if (IS_ERR(sa)) {
4363 ret = PTR_ERR(sa);
4364 sa = NULL;
4365 goto out;
4366 }
4367
4368 /*
4369 * 1 - root item
4370 * 2 - uuid items (received uuid + subvol uuid)
4371 */
4372 trans = btrfs_start_transaction(root, 3);
4373 if (IS_ERR(trans)) {
4374 ret = PTR_ERR(trans);
4375 trans = NULL;
4376 goto out;
4377 }
4378
4379 sa->rtransid = trans->transid;
4380 sa->rtime.sec = ct.tv_sec;
4381 sa->rtime.nsec = ct.tv_nsec;
4382
4383 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4384 BTRFS_UUID_SIZE);
4385 if (received_uuid_changed &&
4386 !btrfs_is_empty_uuid(root_item->received_uuid))
4387 btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
4388 root_item->received_uuid,
4389 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4390 root->root_key.objectid);
4391 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4392 btrfs_set_root_stransid(root_item, sa->stransid);
4393 btrfs_set_root_rtransid(root_item, sa->rtransid);
4394 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4395 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4396 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4397 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4398
4399 ret = btrfs_update_root(trans, root->fs_info->tree_root,
4400 &root->root_key, &root->root_item);
4401 if (ret < 0) {
4402 btrfs_end_transaction(trans, root);
4403 goto out;
4404 }
4405 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4406 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
4407 sa->uuid,
4408 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4409 root->root_key.objectid);
4410 if (ret < 0 && ret != -EEXIST) {
4411 btrfs_abort_transaction(trans, root, ret);
4412 goto out;
4413 }
4414 }
4415 ret = btrfs_commit_transaction(trans, root);
4416 if (ret < 0) {
4417 btrfs_abort_transaction(trans, root, ret);
4418 goto out;
4419 }
4420
4421 ret = copy_to_user(arg, sa, sizeof(*sa));
4422 if (ret)
4423 ret = -EFAULT;
4424
4425 out:
4426 kfree(sa);
4427 up_write(&root->fs_info->subvol_sem);
4428 mnt_drop_write_file(file);
4429 return ret;
4430 }
4431
4432 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
4433 {
4434 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4435 size_t len;
4436 int ret;
4437 char label[BTRFS_LABEL_SIZE];
4438
4439 spin_lock(&root->fs_info->super_lock);
4440 memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
4441 spin_unlock(&root->fs_info->super_lock);
4442
4443 len = strnlen(label, BTRFS_LABEL_SIZE);
4444
4445 if (len == BTRFS_LABEL_SIZE) {
4446 pr_warn("btrfs: label is too long, return the first %zu bytes\n",
4447 --len);
4448 }
4449
4450 ret = copy_to_user(arg, label, len);
4451
4452 return ret ? -EFAULT : 0;
4453 }
4454
4455 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
4456 {
4457 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4458 struct btrfs_super_block *super_block = root->fs_info->super_copy;
4459 struct btrfs_trans_handle *trans;
4460 char label[BTRFS_LABEL_SIZE];
4461 int ret;
4462
4463 if (!capable(CAP_SYS_ADMIN))
4464 return -EPERM;
4465
4466 if (copy_from_user(label, arg, sizeof(label)))
4467 return -EFAULT;
4468
4469 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
4470 pr_err("btrfs: unable to set label with more than %d bytes\n",
4471 BTRFS_LABEL_SIZE - 1);
4472 return -EINVAL;
4473 }
4474
4475 ret = mnt_want_write_file(file);
4476 if (ret)
4477 return ret;
4478
4479 trans = btrfs_start_transaction(root, 0);
4480 if (IS_ERR(trans)) {
4481 ret = PTR_ERR(trans);
4482 goto out_unlock;
4483 }
4484
4485 spin_lock(&root->fs_info->super_lock);
4486 strcpy(super_block->label, label);
4487 spin_unlock(&root->fs_info->super_lock);
4488 ret = btrfs_end_transaction(trans, root);
4489
4490 out_unlock:
4491 mnt_drop_write_file(file);
4492 return ret;
4493 }
4494
4495 long btrfs_ioctl(struct file *file, unsigned int
4496 cmd, unsigned long arg)
4497 {
4498 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4499 void __user *argp = (void __user *)arg;
4500
4501 switch (cmd) {
4502 case FS_IOC_GETFLAGS:
4503 return btrfs_ioctl_getflags(file, argp);
4504 case FS_IOC_SETFLAGS:
4505 return btrfs_ioctl_setflags(file, argp);
4506 case FS_IOC_GETVERSION:
4507 return btrfs_ioctl_getversion(file, argp);
4508 case FITRIM:
4509 return btrfs_ioctl_fitrim(file, argp);
4510 case BTRFS_IOC_SNAP_CREATE:
4511 return btrfs_ioctl_snap_create(file, argp, 0);
4512 case BTRFS_IOC_SNAP_CREATE_V2:
4513 return btrfs_ioctl_snap_create_v2(file, argp, 0);
4514 case BTRFS_IOC_SUBVOL_CREATE:
4515 return btrfs_ioctl_snap_create(file, argp, 1);
4516 case BTRFS_IOC_SUBVOL_CREATE_V2:
4517 return btrfs_ioctl_snap_create_v2(file, argp, 1);
4518 case BTRFS_IOC_SNAP_DESTROY:
4519 return btrfs_ioctl_snap_destroy(file, argp);
4520 case BTRFS_IOC_SUBVOL_GETFLAGS:
4521 return btrfs_ioctl_subvol_getflags(file, argp);
4522 case BTRFS_IOC_SUBVOL_SETFLAGS:
4523 return btrfs_ioctl_subvol_setflags(file, argp);
4524 case BTRFS_IOC_DEFAULT_SUBVOL:
4525 return btrfs_ioctl_default_subvol(file, argp);
4526 case BTRFS_IOC_DEFRAG:
4527 return btrfs_ioctl_defrag(file, NULL);
4528 case BTRFS_IOC_DEFRAG_RANGE:
4529 return btrfs_ioctl_defrag(file, argp);
4530 case BTRFS_IOC_RESIZE:
4531 return btrfs_ioctl_resize(file, argp);
4532 case BTRFS_IOC_ADD_DEV:
4533 return btrfs_ioctl_add_dev(root, argp);
4534 case BTRFS_IOC_RM_DEV:
4535 return btrfs_ioctl_rm_dev(file, argp);
4536 case BTRFS_IOC_FS_INFO:
4537 return btrfs_ioctl_fs_info(root, argp);
4538 case BTRFS_IOC_DEV_INFO:
4539 return btrfs_ioctl_dev_info(root, argp);
4540 case BTRFS_IOC_BALANCE:
4541 return btrfs_ioctl_balance(file, NULL);
4542 case BTRFS_IOC_CLONE:
4543 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
4544 case BTRFS_IOC_CLONE_RANGE:
4545 return btrfs_ioctl_clone_range(file, argp);
4546 case BTRFS_IOC_TRANS_START:
4547 return btrfs_ioctl_trans_start(file);
4548 case BTRFS_IOC_TRANS_END:
4549 return btrfs_ioctl_trans_end(file);
4550 case BTRFS_IOC_TREE_SEARCH:
4551 return btrfs_ioctl_tree_search(file, argp);
4552 case BTRFS_IOC_INO_LOOKUP:
4553 return btrfs_ioctl_ino_lookup(file, argp);
4554 case BTRFS_IOC_INO_PATHS:
4555 return btrfs_ioctl_ino_to_path(root, argp);
4556 case BTRFS_IOC_LOGICAL_INO:
4557 return btrfs_ioctl_logical_to_ino(root, argp);
4558 case BTRFS_IOC_SPACE_INFO:
4559 return btrfs_ioctl_space_info(root, argp);
4560 case BTRFS_IOC_SYNC:
4561 btrfs_sync_fs(file->f_dentry->d_sb, 1);
4562 return 0;
4563 case BTRFS_IOC_START_SYNC:
4564 return btrfs_ioctl_start_sync(root, argp);
4565 case BTRFS_IOC_WAIT_SYNC:
4566 return btrfs_ioctl_wait_sync(root, argp);
4567 case BTRFS_IOC_SCRUB:
4568 return btrfs_ioctl_scrub(file, argp);
4569 case BTRFS_IOC_SCRUB_CANCEL:
4570 return btrfs_ioctl_scrub_cancel(root, argp);
4571 case BTRFS_IOC_SCRUB_PROGRESS:
4572 return btrfs_ioctl_scrub_progress(root, argp);
4573 case BTRFS_IOC_BALANCE_V2:
4574 return btrfs_ioctl_balance(file, argp);
4575 case BTRFS_IOC_BALANCE_CTL:
4576 return btrfs_ioctl_balance_ctl(root, arg);
4577 case BTRFS_IOC_BALANCE_PROGRESS:
4578 return btrfs_ioctl_balance_progress(root, argp);
4579 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
4580 return btrfs_ioctl_set_received_subvol(file, argp);
4581 case BTRFS_IOC_SEND:
4582 return btrfs_ioctl_send(file, argp);
4583 case BTRFS_IOC_GET_DEV_STATS:
4584 return btrfs_ioctl_get_dev_stats(root, argp);
4585 case BTRFS_IOC_QUOTA_CTL:
4586 return btrfs_ioctl_quota_ctl(file, argp);
4587 case BTRFS_IOC_QGROUP_ASSIGN:
4588 return btrfs_ioctl_qgroup_assign(file, argp);
4589 case BTRFS_IOC_QGROUP_CREATE:
4590 return btrfs_ioctl_qgroup_create(file, argp);
4591 case BTRFS_IOC_QGROUP_LIMIT:
4592 return btrfs_ioctl_qgroup_limit(file, argp);
4593 case BTRFS_IOC_QUOTA_RESCAN:
4594 return btrfs_ioctl_quota_rescan(file, argp);
4595 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
4596 return btrfs_ioctl_quota_rescan_status(file, argp);
4597 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
4598 return btrfs_ioctl_quota_rescan_wait(file, argp);
4599 case BTRFS_IOC_DEV_REPLACE:
4600 return btrfs_ioctl_dev_replace(root, argp);
4601 case BTRFS_IOC_GET_FSLABEL:
4602 return btrfs_ioctl_get_fslabel(file, argp);
4603 case BTRFS_IOC_SET_FSLABEL:
4604 return btrfs_ioctl_set_fslabel(file, argp);
4605 case BTRFS_IOC_FILE_EXTENT_SAME:
4606 return btrfs_ioctl_file_extent_same(file, argp);
4607 }
4608
4609 return -ENOTTY;
4610 }
Linux with added FPC-III support