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btrfs: improve messages when updating feature flags
[linux/fpc-iii.git] / fs / btrfs / ioctl.c
blob5b4beebf138ce98a7ce37e71067456a900dfd974
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #include <linux/kernel.h>
7 #include <linux/bio.h>
8 #include <linux/file.h>
9 #include <linux/fs.h>
10 #include <linux/fsnotify.h>
11 #include <linux/pagemap.h>
12 #include <linux/highmem.h>
13 #include <linux/time.h>
14 #include <linux/string.h>
15 #include <linux/backing-dev.h>
16 #include <linux/mount.h>
17 #include <linux/namei.h>
18 #include <linux/writeback.h>
19 #include <linux/compat.h>
20 #include <linux/security.h>
21 #include <linux/xattr.h>
22 #include <linux/mm.h>
23 #include <linux/slab.h>
24 #include <linux/blkdev.h>
25 #include <linux/uuid.h>
26 #include <linux/btrfs.h>
27 #include <linux/uaccess.h>
28 #include <linux/iversion.h>
29 #include "ctree.h"
30 #include "disk-io.h"
31 #include "transaction.h"
32 #include "btrfs_inode.h"
33 #include "print-tree.h"
34 #include "volumes.h"
35 #include "locking.h"
36 #include "inode-map.h"
37 #include "backref.h"
38 #include "rcu-string.h"
39 #include "send.h"
40 #include "dev-replace.h"
41 #include "props.h"
42 #include "sysfs.h"
43 #include "qgroup.h"
44 #include "tree-log.h"
45 #include "compression.h"
46
47 #ifdef CONFIG_64BIT
48 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
49 * structures are incorrect, as the timespec structure from userspace
50 * is 4 bytes too small. We define these alternatives here to teach
51 * the kernel about the 32-bit struct packing.
52 */
53 struct btrfs_ioctl_timespec_32 {
54 __u64 sec;
55 __u32 nsec;
56 } __attribute__ ((__packed__));
57
58 struct btrfs_ioctl_received_subvol_args_32 {
59 char uuid[BTRFS_UUID_SIZE]; /* in */
60 __u64 stransid; /* in */
61 __u64 rtransid; /* out */
62 struct btrfs_ioctl_timespec_32 stime; /* in */
63 struct btrfs_ioctl_timespec_32 rtime; /* out */
64 __u64 flags; /* in */
65 __u64 reserved[16]; /* in */
66 } __attribute__ ((__packed__));
67
68 #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
69 struct btrfs_ioctl_received_subvol_args_32)
70 #endif
71
72 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
73 struct btrfs_ioctl_send_args_32 {
74 __s64 send_fd; /* in */
75 __u64 clone_sources_count; /* in */
76 compat_uptr_t clone_sources; /* in */
77 __u64 parent_root; /* in */
78 __u64 flags; /* in */
79 __u64 reserved[4]; /* in */
80 } __attribute__ ((__packed__));
81
82 #define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \
83 struct btrfs_ioctl_send_args_32)
84 #endif
85
86 static int btrfs_clone(struct inode *src, struct inode *inode,
87 u64 off, u64 olen, u64 olen_aligned, u64 destoff,
88 int no_time_update);
89
90 /* Mask out flags that are inappropriate for the given type of inode. */
91 static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,
92 unsigned int flags)
93 {
94 if (S_ISDIR(inode->i_mode))
95 return flags;
96 else if (S_ISREG(inode->i_mode))
97 return flags & ~FS_DIRSYNC_FL;
98 else
99 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
100 }
101
102 /*
103 * Export internal inode flags to the format expected by the FS_IOC_GETFLAGS
104 * ioctl.
105 */
106 static unsigned int btrfs_inode_flags_to_fsflags(unsigned int flags)
107 {
108 unsigned int iflags = 0;
109
110 if (flags & BTRFS_INODE_SYNC)
111 iflags |= FS_SYNC_FL;
112 if (flags & BTRFS_INODE_IMMUTABLE)
113 iflags |= FS_IMMUTABLE_FL;
114 if (flags & BTRFS_INODE_APPEND)
115 iflags |= FS_APPEND_FL;
116 if (flags & BTRFS_INODE_NODUMP)
117 iflags |= FS_NODUMP_FL;
118 if (flags & BTRFS_INODE_NOATIME)
119 iflags |= FS_NOATIME_FL;
120 if (flags & BTRFS_INODE_DIRSYNC)
121 iflags |= FS_DIRSYNC_FL;
122 if (flags & BTRFS_INODE_NODATACOW)
123 iflags |= FS_NOCOW_FL;
124
125 if (flags & BTRFS_INODE_NOCOMPRESS)
126 iflags |= FS_NOCOMP_FL;
127 else if (flags & BTRFS_INODE_COMPRESS)
128 iflags |= FS_COMPR_FL;
129
130 return iflags;
131 }
132
133 /*
134 * Update inode->i_flags based on the btrfs internal flags.
135 */
136 void btrfs_sync_inode_flags_to_i_flags(struct inode *inode)
137 {
138 struct btrfs_inode *binode = BTRFS_I(inode);
139 unsigned int new_fl = 0;
140
141 if (binode->flags & BTRFS_INODE_SYNC)
142 new_fl |= S_SYNC;
143 if (binode->flags & BTRFS_INODE_IMMUTABLE)
144 new_fl |= S_IMMUTABLE;
145 if (binode->flags & BTRFS_INODE_APPEND)
146 new_fl |= S_APPEND;
147 if (binode->flags & BTRFS_INODE_NOATIME)
148 new_fl |= S_NOATIME;
149 if (binode->flags & BTRFS_INODE_DIRSYNC)
150 new_fl |= S_DIRSYNC;
151
152 set_mask_bits(&inode->i_flags,
153 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
154 new_fl);
155 }
156
157 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
158 {
159 struct btrfs_inode *binode = BTRFS_I(file_inode(file));
160 unsigned int flags = btrfs_inode_flags_to_fsflags(binode->flags);
161
162 if (copy_to_user(arg, &flags, sizeof(flags)))
163 return -EFAULT;
164 return 0;
165 }
166
167 /* Check if @flags are a supported and valid set of FS_*_FL flags */
168 static int check_fsflags(unsigned int flags)
169 {
170 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
171 FS_NOATIME_FL | FS_NODUMP_FL | \
172 FS_SYNC_FL | FS_DIRSYNC_FL | \
173 FS_NOCOMP_FL | FS_COMPR_FL |
174 FS_NOCOW_FL))
175 return -EOPNOTSUPP;
176
177 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
178 return -EINVAL;
179
180 return 0;
181 }
182
183 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
184 {
185 struct inode *inode = file_inode(file);
186 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
187 struct btrfs_inode *binode = BTRFS_I(inode);
188 struct btrfs_root *root = binode->root;
189 struct btrfs_trans_handle *trans;
190 unsigned int fsflags;
191 int ret;
192 const char *comp = NULL;
193 u32 binode_flags = binode->flags;
194
195 if (!inode_owner_or_capable(inode))
196 return -EPERM;
197
198 if (btrfs_root_readonly(root))
199 return -EROFS;
200
201 if (copy_from_user(&fsflags, arg, sizeof(fsflags)))
202 return -EFAULT;
203
204 ret = check_fsflags(fsflags);
205 if (ret)
206 return ret;
207
208 ret = mnt_want_write_file(file);
209 if (ret)
210 return ret;
211
212 inode_lock(inode);
213
214 fsflags = btrfs_mask_fsflags_for_type(inode, fsflags);
215 if ((fsflags ^ btrfs_inode_flags_to_fsflags(binode->flags)) &
216 (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
217 if (!capable(CAP_LINUX_IMMUTABLE)) {
218 ret = -EPERM;
219 goto out_unlock;
220 }
221 }
222
223 if (fsflags & FS_SYNC_FL)
224 binode_flags |= BTRFS_INODE_SYNC;
225 else
226 binode_flags &= ~BTRFS_INODE_SYNC;
227 if (fsflags & FS_IMMUTABLE_FL)
228 binode_flags |= BTRFS_INODE_IMMUTABLE;
229 else
230 binode_flags &= ~BTRFS_INODE_IMMUTABLE;
231 if (fsflags & FS_APPEND_FL)
232 binode_flags |= BTRFS_INODE_APPEND;
233 else
234 binode_flags &= ~BTRFS_INODE_APPEND;
235 if (fsflags & FS_NODUMP_FL)
236 binode_flags |= BTRFS_INODE_NODUMP;
237 else
238 binode_flags &= ~BTRFS_INODE_NODUMP;
239 if (fsflags & FS_NOATIME_FL)
240 binode_flags |= BTRFS_INODE_NOATIME;
241 else
242 binode_flags &= ~BTRFS_INODE_NOATIME;
243 if (fsflags & FS_DIRSYNC_FL)
244 binode_flags |= BTRFS_INODE_DIRSYNC;
245 else
246 binode_flags &= ~BTRFS_INODE_DIRSYNC;
247 if (fsflags & FS_NOCOW_FL) {
248 if (S_ISREG(inode->i_mode)) {
249 /*
250 * It's safe to turn csums off here, no extents exist.
251 * Otherwise we want the flag to reflect the real COW
252 * status of the file and will not set it.
253 */
254 if (inode->i_size == 0)
255 binode_flags |= BTRFS_INODE_NODATACOW |
256 BTRFS_INODE_NODATASUM;
257 } else {
258 binode_flags |= BTRFS_INODE_NODATACOW;
259 }
260 } else {
261 /*
262 * Revert back under same assumptions as above
263 */
264 if (S_ISREG(inode->i_mode)) {
265 if (inode->i_size == 0)
266 binode_flags &= ~(BTRFS_INODE_NODATACOW |
267 BTRFS_INODE_NODATASUM);
268 } else {
269 binode_flags &= ~BTRFS_INODE_NODATACOW;
270 }
271 }
272
273 /*
274 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
275 * flag may be changed automatically if compression code won't make
276 * things smaller.
277 */
278 if (fsflags & FS_NOCOMP_FL) {
279 binode_flags &= ~BTRFS_INODE_COMPRESS;
280 binode_flags |= BTRFS_INODE_NOCOMPRESS;
281 } else if (fsflags & FS_COMPR_FL) {
282
283 if (IS_SWAPFILE(inode)) {
284 ret = -ETXTBSY;
285 goto out_unlock;
286 }
287
288 binode_flags |= BTRFS_INODE_COMPRESS;
289 binode_flags &= ~BTRFS_INODE_NOCOMPRESS;
290
291 comp = btrfs_compress_type2str(fs_info->compress_type);
292 if (!comp || comp[0] == 0)
293 comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);
294 } else {
295 binode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
296 }
297
298 /*
299 * 1 for inode item
300 * 2 for properties
301 */
302 trans = btrfs_start_transaction(root, 3);
303 if (IS_ERR(trans)) {
304 ret = PTR_ERR(trans);
305 goto out_unlock;
306 }
307
308 if (comp) {
309 ret = btrfs_set_prop(trans, inode, "btrfs.compression", comp,
310 strlen(comp), 0);
311 if (ret) {
312 btrfs_abort_transaction(trans, ret);
313 goto out_end_trans;
314 }
315 } else {
316 ret = btrfs_set_prop(trans, inode, "btrfs.compression", NULL,
317 0, 0);
318 if (ret && ret != -ENODATA) {
319 btrfs_abort_transaction(trans, ret);
320 goto out_end_trans;
321 }
322 }
323
324 binode->flags = binode_flags;
325 btrfs_sync_inode_flags_to_i_flags(inode);
326 inode_inc_iversion(inode);
327 inode->i_ctime = current_time(inode);
328 ret = btrfs_update_inode(trans, root, inode);
329
330 out_end_trans:
331 btrfs_end_transaction(trans);
332 out_unlock:
333 inode_unlock(inode);
334 mnt_drop_write_file(file);
335 return ret;
336 }
337
338 /*
339 * Translate btrfs internal inode flags to xflags as expected by the
340 * FS_IOC_FSGETXATT ioctl. Filter only the supported ones, unknown flags are
341 * silently dropped.
342 */
343 static unsigned int btrfs_inode_flags_to_xflags(unsigned int flags)
344 {
345 unsigned int xflags = 0;
346
347 if (flags & BTRFS_INODE_APPEND)
348 xflags |= FS_XFLAG_APPEND;
349 if (flags & BTRFS_INODE_IMMUTABLE)
350 xflags |= FS_XFLAG_IMMUTABLE;
351 if (flags & BTRFS_INODE_NOATIME)
352 xflags |= FS_XFLAG_NOATIME;
353 if (flags & BTRFS_INODE_NODUMP)
354 xflags |= FS_XFLAG_NODUMP;
355 if (flags & BTRFS_INODE_SYNC)
356 xflags |= FS_XFLAG_SYNC;
357
358 return xflags;
359 }
360
361 /* Check if @flags are a supported and valid set of FS_XFLAGS_* flags */
362 static int check_xflags(unsigned int flags)
363 {
364 if (flags & ~(FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE | FS_XFLAG_NOATIME |
365 FS_XFLAG_NODUMP | FS_XFLAG_SYNC))
366 return -EOPNOTSUPP;
367 return 0;
368 }
369
370 /*
371 * Set the xflags from the internal inode flags. The remaining items of fsxattr
372 * are zeroed.
373 */
374 static int btrfs_ioctl_fsgetxattr(struct file *file, void __user *arg)
375 {
376 struct btrfs_inode *binode = BTRFS_I(file_inode(file));
377 struct fsxattr fa;
378
379 memset(&fa, 0, sizeof(fa));
380 fa.fsx_xflags = btrfs_inode_flags_to_xflags(binode->flags);
381
382 if (copy_to_user(arg, &fa, sizeof(fa)))
383 return -EFAULT;
384
385 return 0;
386 }
387
388 static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg)
389 {
390 struct inode *inode = file_inode(file);
391 struct btrfs_inode *binode = BTRFS_I(inode);
392 struct btrfs_root *root = binode->root;
393 struct btrfs_trans_handle *trans;
394 struct fsxattr fa;
395 unsigned old_flags;
396 unsigned old_i_flags;
397 int ret = 0;
398
399 if (!inode_owner_or_capable(inode))
400 return -EPERM;
401
402 if (btrfs_root_readonly(root))
403 return -EROFS;
404
405 memset(&fa, 0, sizeof(fa));
406 if (copy_from_user(&fa, arg, sizeof(fa)))
407 return -EFAULT;
408
409 ret = check_xflags(fa.fsx_xflags);
410 if (ret)
411 return ret;
412
413 if (fa.fsx_extsize != 0 || fa.fsx_projid != 0 || fa.fsx_cowextsize != 0)
414 return -EOPNOTSUPP;
415
416 ret = mnt_want_write_file(file);
417 if (ret)
418 return ret;
419
420 inode_lock(inode);
421
422 old_flags = binode->flags;
423 old_i_flags = inode->i_flags;
424
425 /* We need the capabilities to change append-only or immutable inode */
426 if (((old_flags & (BTRFS_INODE_APPEND | BTRFS_INODE_IMMUTABLE)) ||
427 (fa.fsx_xflags & (FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE))) &&
428 !capable(CAP_LINUX_IMMUTABLE)) {
429 ret = -EPERM;
430 goto out_unlock;
431 }
432
433 if (fa.fsx_xflags & FS_XFLAG_SYNC)
434 binode->flags |= BTRFS_INODE_SYNC;
435 else
436 binode->flags &= ~BTRFS_INODE_SYNC;
437 if (fa.fsx_xflags & FS_XFLAG_IMMUTABLE)
438 binode->flags |= BTRFS_INODE_IMMUTABLE;
439 else
440 binode->flags &= ~BTRFS_INODE_IMMUTABLE;
441 if (fa.fsx_xflags & FS_XFLAG_APPEND)
442 binode->flags |= BTRFS_INODE_APPEND;
443 else
444 binode->flags &= ~BTRFS_INODE_APPEND;
445 if (fa.fsx_xflags & FS_XFLAG_NODUMP)
446 binode->flags |= BTRFS_INODE_NODUMP;
447 else
448 binode->flags &= ~BTRFS_INODE_NODUMP;
449 if (fa.fsx_xflags & FS_XFLAG_NOATIME)
450 binode->flags |= BTRFS_INODE_NOATIME;
451 else
452 binode->flags &= ~BTRFS_INODE_NOATIME;
453
454 /* 1 item for the inode */
455 trans = btrfs_start_transaction(root, 1);
456 if (IS_ERR(trans)) {
457 ret = PTR_ERR(trans);
458 goto out_unlock;
459 }
460
461 btrfs_sync_inode_flags_to_i_flags(inode);
462 inode_inc_iversion(inode);
463 inode->i_ctime = current_time(inode);
464 ret = btrfs_update_inode(trans, root, inode);
465
466 btrfs_end_transaction(trans);
467
468 out_unlock:
469 if (ret) {
470 binode->flags = old_flags;
471 inode->i_flags = old_i_flags;
472 }
473
474 inode_unlock(inode);
475 mnt_drop_write_file(file);
476
477 return ret;
478 }
479
480 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
481 {
482 struct inode *inode = file_inode(file);
483
484 return put_user(inode->i_generation, arg);
485 }
486
487 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
488 {
489 struct inode *inode = file_inode(file);
490 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
491 struct btrfs_device *device;
492 struct request_queue *q;
493 struct fstrim_range range;
494 u64 minlen = ULLONG_MAX;
495 u64 num_devices = 0;
496 int ret;
497
498 if (!capable(CAP_SYS_ADMIN))
499 return -EPERM;
500
501 /*
502 * If the fs is mounted with nologreplay, which requires it to be
503 * mounted in RO mode as well, we can not allow discard on free space
504 * inside block groups, because log trees refer to extents that are not
505 * pinned in a block group's free space cache (pinning the extents is
506 * precisely the first phase of replaying a log tree).
507 */
508 if (btrfs_test_opt(fs_info, NOLOGREPLAY))
509 return -EROFS;
510
511 rcu_read_lock();
512 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
513 dev_list) {
514 if (!device->bdev)
515 continue;
516 q = bdev_get_queue(device->bdev);
517 if (blk_queue_discard(q)) {
518 num_devices++;
519 minlen = min_t(u64, q->limits.discard_granularity,
520 minlen);
521 }
522 }
523 rcu_read_unlock();
524
525 if (!num_devices)
526 return -EOPNOTSUPP;
527 if (copy_from_user(&range, arg, sizeof(range)))
528 return -EFAULT;
529
530 /*
531 * NOTE: Don't truncate the range using super->total_bytes. Bytenr of
532 * block group is in the logical address space, which can be any
533 * sectorsize aligned bytenr in the range [0, U64_MAX].
534 */
535 if (range.len < fs_info->sb->s_blocksize)
536 return -EINVAL;
537
538 range.minlen = max(range.minlen, minlen);
539 ret = btrfs_trim_fs(fs_info, &range);
540 if (ret < 0)
541 return ret;
542
543 if (copy_to_user(arg, &range, sizeof(range)))
544 return -EFAULT;
545
546 return 0;
547 }
548
549 int btrfs_is_empty_uuid(u8 *uuid)
550 {
551 int i;
552
553 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
554 if (uuid[i])
555 return 0;
556 }
557 return 1;
558 }
559
560 static noinline int create_subvol(struct inode *dir,
561 struct dentry *dentry,
562 const char *name, int namelen,
563 u64 *async_transid,
564 struct btrfs_qgroup_inherit *inherit)
565 {
566 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
567 struct btrfs_trans_handle *trans;
568 struct btrfs_key key;
569 struct btrfs_root_item *root_item;
570 struct btrfs_inode_item *inode_item;
571 struct extent_buffer *leaf;
572 struct btrfs_root *root = BTRFS_I(dir)->root;
573 struct btrfs_root *new_root;
574 struct btrfs_block_rsv block_rsv;
575 struct timespec64 cur_time = current_time(dir);
576 struct inode *inode;
577 int ret;
578 int err;
579 u64 objectid;
580 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
581 u64 index = 0;
582 uuid_le new_uuid;
583
584 root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
585 if (!root_item)
586 return -ENOMEM;
587
588 ret = btrfs_find_free_objectid(fs_info->tree_root, &objectid);
589 if (ret)
590 goto fail_free;
591
592 /*
593 * Don't create subvolume whose level is not zero. Or qgroup will be
594 * screwed up since it assumes subvolume qgroup's level to be 0.
595 */
596 if (btrfs_qgroup_level(objectid)) {
597 ret = -ENOSPC;
598 goto fail_free;
599 }
600
601 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
602 /*
603 * The same as the snapshot creation, please see the comment
604 * of create_snapshot().
605 */
606 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 8, false);
607 if (ret)
608 goto fail_free;
609
610 trans = btrfs_start_transaction(root, 0);
611 if (IS_ERR(trans)) {
612 ret = PTR_ERR(trans);
613 btrfs_subvolume_release_metadata(fs_info, &block_rsv);
614 goto fail_free;
615 }
616 trans->block_rsv = &block_rsv;
617 trans->bytes_reserved = block_rsv.size;
618
619 ret = btrfs_qgroup_inherit(trans, 0, objectid, inherit);
620 if (ret)
621 goto fail;
622
623 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
624 if (IS_ERR(leaf)) {
625 ret = PTR_ERR(leaf);
626 goto fail;
627 }
628
629 btrfs_mark_buffer_dirty(leaf);
630
631 inode_item = &root_item->inode;
632 btrfs_set_stack_inode_generation(inode_item, 1);
633 btrfs_set_stack_inode_size(inode_item, 3);
634 btrfs_set_stack_inode_nlink(inode_item, 1);
635 btrfs_set_stack_inode_nbytes(inode_item,
636 fs_info->nodesize);
637 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
638
639 btrfs_set_root_flags(root_item, 0);
640 btrfs_set_root_limit(root_item, 0);
641 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
642
643 btrfs_set_root_bytenr(root_item, leaf->start);
644 btrfs_set_root_generation(root_item, trans->transid);
645 btrfs_set_root_level(root_item, 0);
646 btrfs_set_root_refs(root_item, 1);
647 btrfs_set_root_used(root_item, leaf->len);
648 btrfs_set_root_last_snapshot(root_item, 0);
649
650 btrfs_set_root_generation_v2(root_item,
651 btrfs_root_generation(root_item));
652 uuid_le_gen(&new_uuid);
653 memcpy(root_item->uuid, new_uuid.b, BTRFS_UUID_SIZE);
654 btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);
655 btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);
656 root_item->ctime = root_item->otime;
657 btrfs_set_root_ctransid(root_item, trans->transid);
658 btrfs_set_root_otransid(root_item, trans->transid);
659
660 btrfs_tree_unlock(leaf);
661 free_extent_buffer(leaf);
662 leaf = NULL;
663
664 btrfs_set_root_dirid(root_item, new_dirid);
665
666 key.objectid = objectid;
667 key.offset = 0;
668 key.type = BTRFS_ROOT_ITEM_KEY;
669 ret = btrfs_insert_root(trans, fs_info->tree_root, &key,
670 root_item);
671 if (ret)
672 goto fail;
673
674 key.offset = (u64)-1;
675 new_root = btrfs_read_fs_root_no_name(fs_info, &key);
676 if (IS_ERR(new_root)) {
677 ret = PTR_ERR(new_root);
678 btrfs_abort_transaction(trans, ret);
679 goto fail;
680 }
681
682 btrfs_record_root_in_trans(trans, new_root);
683
684 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
685 if (ret) {
686 /* We potentially lose an unused inode item here */
687 btrfs_abort_transaction(trans, ret);
688 goto fail;
689 }
690
691 mutex_lock(&new_root->objectid_mutex);
692 new_root->highest_objectid = new_dirid;
693 mutex_unlock(&new_root->objectid_mutex);
694
695 /*
696 * insert the directory item
697 */
698 ret = btrfs_set_inode_index(BTRFS_I(dir), &index);
699 if (ret) {
700 btrfs_abort_transaction(trans, ret);
701 goto fail;
702 }
703
704 ret = btrfs_insert_dir_item(trans, name, namelen, BTRFS_I(dir), &key,
705 BTRFS_FT_DIR, index);
706 if (ret) {
707 btrfs_abort_transaction(trans, ret);
708 goto fail;
709 }
710
711 btrfs_i_size_write(BTRFS_I(dir), dir->i_size + namelen * 2);
712 ret = btrfs_update_inode(trans, root, dir);
713 BUG_ON(ret);
714
715 ret = btrfs_add_root_ref(trans, objectid, root->root_key.objectid,
716 btrfs_ino(BTRFS_I(dir)), index, name, namelen);
717 BUG_ON(ret);
718
719 ret = btrfs_uuid_tree_add(trans, root_item->uuid,
720 BTRFS_UUID_KEY_SUBVOL, objectid);
721 if (ret)
722 btrfs_abort_transaction(trans, ret);
723
724 fail:
725 kfree(root_item);
726 trans->block_rsv = NULL;
727 trans->bytes_reserved = 0;
728 btrfs_subvolume_release_metadata(fs_info, &block_rsv);
729
730 if (async_transid) {
731 *async_transid = trans->transid;
732 err = btrfs_commit_transaction_async(trans, 1);
733 if (err)
734 err = btrfs_commit_transaction(trans);
735 } else {
736 err = btrfs_commit_transaction(trans);
737 }
738 if (err && !ret)
739 ret = err;
740
741 if (!ret) {
742 inode = btrfs_lookup_dentry(dir, dentry);
743 if (IS_ERR(inode))
744 return PTR_ERR(inode);
745 d_instantiate(dentry, inode);
746 }
747 return ret;
748
749 fail_free:
750 kfree(root_item);
751 return ret;
752 }
753
754 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
755 struct dentry *dentry,
756 u64 *async_transid, bool readonly,
757 struct btrfs_qgroup_inherit *inherit)
758 {
759 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
760 struct inode *inode;
761 struct btrfs_pending_snapshot *pending_snapshot;
762 struct btrfs_trans_handle *trans;
763 int ret;
764 bool snapshot_force_cow = false;
765
766 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
767 return -EINVAL;
768
769 if (atomic_read(&root->nr_swapfiles)) {
770 btrfs_warn(fs_info,
771 "cannot snapshot subvolume with active swapfile");
772 return -ETXTBSY;
773 }
774
775 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL);
776 if (!pending_snapshot)
777 return -ENOMEM;
778
779 pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
780 GFP_KERNEL);
781 pending_snapshot->path = btrfs_alloc_path();
782 if (!pending_snapshot->root_item || !pending_snapshot->path) {
783 ret = -ENOMEM;
784 goto free_pending;
785 }
786
787 /*
788 * Force new buffered writes to reserve space even when NOCOW is
789 * possible. This is to avoid later writeback (running dealloc) to
790 * fallback to COW mode and unexpectedly fail with ENOSPC.
791 */
792 atomic_inc(&root->will_be_snapshotted);
793 smp_mb__after_atomic();
794 /* wait for no snapshot writes */
795 wait_event(root->subv_writers->wait,
796 percpu_counter_sum(&root->subv_writers->counter) == 0);
797
798 ret = btrfs_start_delalloc_snapshot(root);
799 if (ret)
800 goto dec_and_free;
801
802 /*
803 * All previous writes have started writeback in NOCOW mode, so now
804 * we force future writes to fallback to COW mode during snapshot
805 * creation.
806 */
807 atomic_inc(&root->snapshot_force_cow);
808 snapshot_force_cow = true;
809
810 btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
811
812 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
813 BTRFS_BLOCK_RSV_TEMP);
814 /*
815 * 1 - parent dir inode
816 * 2 - dir entries
817 * 1 - root item
818 * 2 - root ref/backref
819 * 1 - root of snapshot
820 * 1 - UUID item
821 */
822 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
823 &pending_snapshot->block_rsv, 8,
824 false);
825 if (ret)
826 goto dec_and_free;
827
828 pending_snapshot->dentry = dentry;
829 pending_snapshot->root = root;
830 pending_snapshot->readonly = readonly;
831 pending_snapshot->dir = dir;
832 pending_snapshot->inherit = inherit;
833
834 trans = btrfs_start_transaction(root, 0);
835 if (IS_ERR(trans)) {
836 ret = PTR_ERR(trans);
837 goto fail;
838 }
839
840 spin_lock(&fs_info->trans_lock);
841 list_add(&pending_snapshot->list,
842 &trans->transaction->pending_snapshots);
843 spin_unlock(&fs_info->trans_lock);
844 if (async_transid) {
845 *async_transid = trans->transid;
846 ret = btrfs_commit_transaction_async(trans, 1);
847 if (ret)
848 ret = btrfs_commit_transaction(trans);
849 } else {
850 ret = btrfs_commit_transaction(trans);
851 }
852 if (ret)
853 goto fail;
854
855 ret = pending_snapshot->error;
856 if (ret)
857 goto fail;
858
859 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
860 if (ret)
861 goto fail;
862
863 inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
864 if (IS_ERR(inode)) {
865 ret = PTR_ERR(inode);
866 goto fail;
867 }
868
869 d_instantiate(dentry, inode);
870 ret = 0;
871 fail:
872 btrfs_subvolume_release_metadata(fs_info, &pending_snapshot->block_rsv);
873 dec_and_free:
874 if (snapshot_force_cow)
875 atomic_dec(&root->snapshot_force_cow);
876 if (atomic_dec_and_test(&root->will_be_snapshotted))
877 wake_up_var(&root->will_be_snapshotted);
878 free_pending:
879 kfree(pending_snapshot->root_item);
880 btrfs_free_path(pending_snapshot->path);
881 kfree(pending_snapshot);
882
883 return ret;
884 }
885
886 /* copy of may_delete in fs/namei.c()
887 * Check whether we can remove a link victim from directory dir, check
888 * whether the type of victim is right.
889 * 1. We can't do it if dir is read-only (done in permission())
890 * 2. We should have write and exec permissions on dir
891 * 3. We can't remove anything from append-only dir
892 * 4. We can't do anything with immutable dir (done in permission())
893 * 5. If the sticky bit on dir is set we should either
894 * a. be owner of dir, or
895 * b. be owner of victim, or
896 * c. have CAP_FOWNER capability
897 * 6. If the victim is append-only or immutable we can't do anything with
898 * links pointing to it.
899 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
900 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
901 * 9. We can't remove a root or mountpoint.
902 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
903 * nfs_async_unlink().
904 */
905
906 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
907 {
908 int error;
909
910 if (d_really_is_negative(victim))
911 return -ENOENT;
912
913 BUG_ON(d_inode(victim->d_parent) != dir);
914 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
915
916 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
917 if (error)
918 return error;
919 if (IS_APPEND(dir))
920 return -EPERM;
921 if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
922 IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
923 return -EPERM;
924 if (isdir) {
925 if (!d_is_dir(victim))
926 return -ENOTDIR;
927 if (IS_ROOT(victim))
928 return -EBUSY;
929 } else if (d_is_dir(victim))
930 return -EISDIR;
931 if (IS_DEADDIR(dir))
932 return -ENOENT;
933 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
934 return -EBUSY;
935 return 0;
936 }
937
938 /* copy of may_create in fs/namei.c() */
939 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
940 {
941 if (d_really_is_positive(child))
942 return -EEXIST;
943 if (IS_DEADDIR(dir))
944 return -ENOENT;
945 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
946 }
947
948 /*
949 * Create a new subvolume below @parent. This is largely modeled after
950 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
951 * inside this filesystem so it's quite a bit simpler.
952 */
953 static noinline int btrfs_mksubvol(const struct path *parent,
954 const char *name, int namelen,
955 struct btrfs_root *snap_src,
956 u64 *async_transid, bool readonly,
957 struct btrfs_qgroup_inherit *inherit)
958 {
959 struct inode *dir = d_inode(parent->dentry);
960 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
961 struct dentry *dentry;
962 int error;
963
964 error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
965 if (error == -EINTR)
966 return error;
967
968 dentry = lookup_one_len(name, parent->dentry, namelen);
969 error = PTR_ERR(dentry);
970 if (IS_ERR(dentry))
971 goto out_unlock;
972
973 error = btrfs_may_create(dir, dentry);
974 if (error)
975 goto out_dput;
976
977 /*
978 * even if this name doesn't exist, we may get hash collisions.
979 * check for them now when we can safely fail
980 */
981 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
982 dir->i_ino, name,
983 namelen);
984 if (error)
985 goto out_dput;
986
987 down_read(&fs_info->subvol_sem);
988
989 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
990 goto out_up_read;
991
992 if (snap_src) {
993 error = create_snapshot(snap_src, dir, dentry,
994 async_transid, readonly, inherit);
995 } else {
996 error = create_subvol(dir, dentry, name, namelen,
997 async_transid, inherit);
998 }
999 if (!error)
1000 fsnotify_mkdir(dir, dentry);
1001 out_up_read:
1002 up_read(&fs_info->subvol_sem);
1003 out_dput:
1004 dput(dentry);
1005 out_unlock:
1006 inode_unlock(dir);
1007 return error;
1008 }
1009
1010 /*
1011 * When we're defragging a range, we don't want to kick it off again
1012 * if it is really just waiting for delalloc to send it down.
1013 * If we find a nice big extent or delalloc range for the bytes in the
1014 * file you want to defrag, we return 0 to let you know to skip this
1015 * part of the file
1016 */
1017 static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
1018 {
1019 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1020 struct extent_map *em = NULL;
1021 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1022 u64 end;
1023
1024 read_lock(&em_tree->lock);
1025 em = lookup_extent_mapping(em_tree, offset, PAGE_SIZE);
1026 read_unlock(&em_tree->lock);
1027
1028 if (em) {
1029 end = extent_map_end(em);
1030 free_extent_map(em);
1031 if (end - offset > thresh)
1032 return 0;
1033 }
1034 /* if we already have a nice delalloc here, just stop */
1035 thresh /= 2;
1036 end = count_range_bits(io_tree, &offset, offset + thresh,
1037 thresh, EXTENT_DELALLOC, 1);
1038 if (end >= thresh)
1039 return 0;
1040 return 1;
1041 }
1042
1043 /*
1044 * helper function to walk through a file and find extents
1045 * newer than a specific transid, and smaller than thresh.
1046 *
1047 * This is used by the defragging code to find new and small
1048 * extents
1049 */
1050 static int find_new_extents(struct btrfs_root *root,
1051 struct inode *inode, u64 newer_than,
1052 u64 *off, u32 thresh)
1053 {
1054 struct btrfs_path *path;
1055 struct btrfs_key min_key;
1056 struct extent_buffer *leaf;
1057 struct btrfs_file_extent_item *extent;
1058 int type;
1059 int ret;
1060 u64 ino = btrfs_ino(BTRFS_I(inode));
1061
1062 path = btrfs_alloc_path();
1063 if (!path)
1064 return -ENOMEM;
1065
1066 min_key.objectid = ino;
1067 min_key.type = BTRFS_EXTENT_DATA_KEY;
1068 min_key.offset = *off;
1069
1070 while (1) {
1071 ret = btrfs_search_forward(root, &min_key, path, newer_than);
1072 if (ret != 0)
1073 goto none;
1074 process_slot:
1075 if (min_key.objectid != ino)
1076 goto none;
1077 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
1078 goto none;
1079
1080 leaf = path->nodes[0];
1081 extent = btrfs_item_ptr(leaf, path->slots[0],
1082 struct btrfs_file_extent_item);
1083
1084 type = btrfs_file_extent_type(leaf, extent);
1085 if (type == BTRFS_FILE_EXTENT_REG &&
1086 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
1087 check_defrag_in_cache(inode, min_key.offset, thresh)) {
1088 *off = min_key.offset;
1089 btrfs_free_path(path);
1090 return 0;
1091 }
1092
1093 path->slots[0]++;
1094 if (path->slots[0] < btrfs_header_nritems(leaf)) {
1095 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
1096 goto process_slot;
1097 }
1098
1099 if (min_key.offset == (u64)-1)
1100 goto none;
1101
1102 min_key.offset++;
1103 btrfs_release_path(path);
1104 }
1105 none:
1106 btrfs_free_path(path);
1107 return -ENOENT;
1108 }
1109
1110 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
1111 {
1112 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1113 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1114 struct extent_map *em;
1115 u64 len = PAGE_SIZE;
1116
1117 /*
1118 * hopefully we have this extent in the tree already, try without
1119 * the full extent lock
1120 */
1121 read_lock(&em_tree->lock);
1122 em = lookup_extent_mapping(em_tree, start, len);
1123 read_unlock(&em_tree->lock);
1124
1125 if (!em) {
1126 struct extent_state *cached = NULL;
1127 u64 end = start + len - 1;
1128
1129 /* get the big lock and read metadata off disk */
1130 lock_extent_bits(io_tree, start, end, &cached);
1131 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len, 0);
1132 unlock_extent_cached(io_tree, start, end, &cached);
1133
1134 if (IS_ERR(em))
1135 return NULL;
1136 }
1137
1138 return em;
1139 }
1140
1141 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1142 {
1143 struct extent_map *next;
1144 bool ret = true;
1145
1146 /* this is the last extent */
1147 if (em->start + em->len >= i_size_read(inode))
1148 return false;
1149
1150 next = defrag_lookup_extent(inode, em->start + em->len);
1151 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1152 ret = false;
1153 else if ((em->block_start + em->block_len == next->block_start) &&
1154 (em->block_len > SZ_128K && next->block_len > SZ_128K))
1155 ret = false;
1156
1157 free_extent_map(next);
1158 return ret;
1159 }
1160
1161 static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1162 u64 *last_len, u64 *skip, u64 *defrag_end,
1163 int compress)
1164 {
1165 struct extent_map *em;
1166 int ret = 1;
1167 bool next_mergeable = true;
1168 bool prev_mergeable = true;
1169
1170 /*
1171 * make sure that once we start defragging an extent, we keep on
1172 * defragging it
1173 */
1174 if (start < *defrag_end)
1175 return 1;
1176
1177 *skip = 0;
1178
1179 em = defrag_lookup_extent(inode, start);
1180 if (!em)
1181 return 0;
1182
1183 /* this will cover holes, and inline extents */
1184 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1185 ret = 0;
1186 goto out;
1187 }
1188
1189 if (!*defrag_end)
1190 prev_mergeable = false;
1191
1192 next_mergeable = defrag_check_next_extent(inode, em);
1193 /*
1194 * we hit a real extent, if it is big or the next extent is not a
1195 * real extent, don't bother defragging it
1196 */
1197 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1198 (em->len >= thresh || (!next_mergeable && !prev_mergeable)))
1199 ret = 0;
1200 out:
1201 /*
1202 * last_len ends up being a counter of how many bytes we've defragged.
1203 * every time we choose not to defrag an extent, we reset *last_len
1204 * so that the next tiny extent will force a defrag.
1205 *
1206 * The end result of this is that tiny extents before a single big
1207 * extent will force at least part of that big extent to be defragged.
1208 */
1209 if (ret) {
1210 *defrag_end = extent_map_end(em);
1211 } else {
1212 *last_len = 0;
1213 *skip = extent_map_end(em);
1214 *defrag_end = 0;
1215 }
1216
1217 free_extent_map(em);
1218 return ret;
1219 }
1220
1221 /*
1222 * it doesn't do much good to defrag one or two pages
1223 * at a time. This pulls in a nice chunk of pages
1224 * to COW and defrag.
1225 *
1226 * It also makes sure the delalloc code has enough
1227 * dirty data to avoid making new small extents as part
1228 * of the defrag
1229 *
1230 * It's a good idea to start RA on this range
1231 * before calling this.
1232 */
1233 static int cluster_pages_for_defrag(struct inode *inode,
1234 struct page **pages,
1235 unsigned long start_index,
1236 unsigned long num_pages)
1237 {
1238 unsigned long file_end;
1239 u64 isize = i_size_read(inode);
1240 u64 page_start;
1241 u64 page_end;
1242 u64 page_cnt;
1243 int ret;
1244 int i;
1245 int i_done;
1246 struct btrfs_ordered_extent *ordered;
1247 struct extent_state *cached_state = NULL;
1248 struct extent_io_tree *tree;
1249 struct extent_changeset *data_reserved = NULL;
1250 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1251
1252 file_end = (isize - 1) >> PAGE_SHIFT;
1253 if (!isize || start_index > file_end)
1254 return 0;
1255
1256 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1257
1258 ret = btrfs_delalloc_reserve_space(inode, &data_reserved,
1259 start_index << PAGE_SHIFT,
1260 page_cnt << PAGE_SHIFT);
1261 if (ret)
1262 return ret;
1263 i_done = 0;
1264 tree = &BTRFS_I(inode)->io_tree;
1265
1266 /* step one, lock all the pages */
1267 for (i = 0; i < page_cnt; i++) {
1268 struct page *page;
1269 again:
1270 page = find_or_create_page(inode->i_mapping,
1271 start_index + i, mask);
1272 if (!page)
1273 break;
1274
1275 page_start = page_offset(page);
1276 page_end = page_start + PAGE_SIZE - 1;
1277 while (1) {
1278 lock_extent_bits(tree, page_start, page_end,
1279 &cached_state);
1280 ordered = btrfs_lookup_ordered_extent(inode,
1281 page_start);
1282 unlock_extent_cached(tree, page_start, page_end,
1283 &cached_state);
1284 if (!ordered)
1285 break;
1286
1287 unlock_page(page);
1288 btrfs_start_ordered_extent(inode, ordered, 1);
1289 btrfs_put_ordered_extent(ordered);
1290 lock_page(page);
1291 /*
1292 * we unlocked the page above, so we need check if
1293 * it was released or not.
1294 */
1295 if (page->mapping != inode->i_mapping) {
1296 unlock_page(page);
1297 put_page(page);
1298 goto again;
1299 }
1300 }
1301
1302 if (!PageUptodate(page)) {
1303 btrfs_readpage(NULL, page);
1304 lock_page(page);
1305 if (!PageUptodate(page)) {
1306 unlock_page(page);
1307 put_page(page);
1308 ret = -EIO;
1309 break;
1310 }
1311 }
1312
1313 if (page->mapping != inode->i_mapping) {
1314 unlock_page(page);
1315 put_page(page);
1316 goto again;
1317 }
1318
1319 pages[i] = page;
1320 i_done++;
1321 }
1322 if (!i_done || ret)
1323 goto out;
1324
1325 if (!(inode->i_sb->s_flags & SB_ACTIVE))
1326 goto out;
1327
1328 /*
1329 * so now we have a nice long stream of locked
1330 * and up to date pages, lets wait on them
1331 */
1332 for (i = 0; i < i_done; i++)
1333 wait_on_page_writeback(pages[i]);
1334
1335 page_start = page_offset(pages[0]);
1336 page_end = page_offset(pages[i_done - 1]) + PAGE_SIZE;
1337
1338 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1339 page_start, page_end - 1, &cached_state);
1340 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1341 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1342 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1343 &cached_state);
1344
1345 if (i_done != page_cnt) {
1346 spin_lock(&BTRFS_I(inode)->lock);
1347 btrfs_mod_outstanding_extents(BTRFS_I(inode), 1);
1348 spin_unlock(&BTRFS_I(inode)->lock);
1349 btrfs_delalloc_release_space(inode, data_reserved,
1350 start_index << PAGE_SHIFT,
1351 (page_cnt - i_done) << PAGE_SHIFT, true);
1352 }
1353
1354
1355 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1356 &cached_state);
1357
1358 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1359 page_start, page_end - 1, &cached_state);
1360
1361 for (i = 0; i < i_done; i++) {
1362 clear_page_dirty_for_io(pages[i]);
1363 ClearPageChecked(pages[i]);
1364 set_page_extent_mapped(pages[i]);
1365 set_page_dirty(pages[i]);
1366 unlock_page(pages[i]);
1367 put_page(pages[i]);
1368 }
1369 btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT,
1370 false);
1371 extent_changeset_free(data_reserved);
1372 return i_done;
1373 out:
1374 for (i = 0; i < i_done; i++) {
1375 unlock_page(pages[i]);
1376 put_page(pages[i]);
1377 }
1378 btrfs_delalloc_release_space(inode, data_reserved,
1379 start_index << PAGE_SHIFT,
1380 page_cnt << PAGE_SHIFT, true);
1381 btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT,
1382 true);
1383 extent_changeset_free(data_reserved);
1384 return ret;
1385
1386 }
1387
1388 int btrfs_defrag_file(struct inode *inode, struct file *file,
1389 struct btrfs_ioctl_defrag_range_args *range,
1390 u64 newer_than, unsigned long max_to_defrag)
1391 {
1392 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1393 struct btrfs_root *root = BTRFS_I(inode)->root;
1394 struct file_ra_state *ra = NULL;
1395 unsigned long last_index;
1396 u64 isize = i_size_read(inode);
1397 u64 last_len = 0;
1398 u64 skip = 0;
1399 u64 defrag_end = 0;
1400 u64 newer_off = range->start;
1401 unsigned long i;
1402 unsigned long ra_index = 0;
1403 int ret;
1404 int defrag_count = 0;
1405 int compress_type = BTRFS_COMPRESS_ZLIB;
1406 u32 extent_thresh = range->extent_thresh;
1407 unsigned long max_cluster = SZ_256K >> PAGE_SHIFT;
1408 unsigned long cluster = max_cluster;
1409 u64 new_align = ~((u64)SZ_128K - 1);
1410 struct page **pages = NULL;
1411 bool do_compress = range->flags & BTRFS_DEFRAG_RANGE_COMPRESS;
1412
1413 if (isize == 0)
1414 return 0;
1415
1416 if (range->start >= isize)
1417 return -EINVAL;
1418
1419 if (do_compress) {
1420 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1421 return -EINVAL;
1422 if (range->compress_type)
1423 compress_type = range->compress_type;
1424 }
1425
1426 if (extent_thresh == 0)
1427 extent_thresh = SZ_256K;
1428
1429 /*
1430 * If we were not given a file, allocate a readahead context. As
1431 * readahead is just an optimization, defrag will work without it so
1432 * we don't error out.
1433 */
1434 if (!file) {
1435 ra = kzalloc(sizeof(*ra), GFP_KERNEL);
1436 if (ra)
1437 file_ra_state_init(ra, inode->i_mapping);
1438 } else {
1439 ra = &file->f_ra;
1440 }
1441
1442 pages = kmalloc_array(max_cluster, sizeof(struct page *), GFP_KERNEL);
1443 if (!pages) {
1444 ret = -ENOMEM;
1445 goto out_ra;
1446 }
1447
1448 /* find the last page to defrag */
1449 if (range->start + range->len > range->start) {
1450 last_index = min_t(u64, isize - 1,
1451 range->start + range->len - 1) >> PAGE_SHIFT;
1452 } else {
1453 last_index = (isize - 1) >> PAGE_SHIFT;
1454 }
1455
1456 if (newer_than) {
1457 ret = find_new_extents(root, inode, newer_than,
1458 &newer_off, SZ_64K);
1459 if (!ret) {
1460 range->start = newer_off;
1461 /*
1462 * we always align our defrag to help keep
1463 * the extents in the file evenly spaced
1464 */
1465 i = (newer_off & new_align) >> PAGE_SHIFT;
1466 } else
1467 goto out_ra;
1468 } else {
1469 i = range->start >> PAGE_SHIFT;
1470 }
1471 if (!max_to_defrag)
1472 max_to_defrag = last_index - i + 1;
1473
1474 /*
1475 * make writeback starts from i, so the defrag range can be
1476 * written sequentially.
1477 */
1478 if (i < inode->i_mapping->writeback_index)
1479 inode->i_mapping->writeback_index = i;
1480
1481 while (i <= last_index && defrag_count < max_to_defrag &&
1482 (i < DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE))) {
1483 /*
1484 * make sure we stop running if someone unmounts
1485 * the FS
1486 */
1487 if (!(inode->i_sb->s_flags & SB_ACTIVE))
1488 break;
1489
1490 if (btrfs_defrag_cancelled(fs_info)) {
1491 btrfs_debug(fs_info, "defrag_file cancelled");
1492 ret = -EAGAIN;
1493 break;
1494 }
1495
1496 if (!should_defrag_range(inode, (u64)i << PAGE_SHIFT,
1497 extent_thresh, &last_len, &skip,
1498 &defrag_end, do_compress)){
1499 unsigned long next;
1500 /*
1501 * the should_defrag function tells us how much to skip
1502 * bump our counter by the suggested amount
1503 */
1504 next = DIV_ROUND_UP(skip, PAGE_SIZE);
1505 i = max(i + 1, next);
1506 continue;
1507 }
1508
1509 if (!newer_than) {
1510 cluster = (PAGE_ALIGN(defrag_end) >>
1511 PAGE_SHIFT) - i;
1512 cluster = min(cluster, max_cluster);
1513 } else {
1514 cluster = max_cluster;
1515 }
1516
1517 if (i + cluster > ra_index) {
1518 ra_index = max(i, ra_index);
1519 if (ra)
1520 page_cache_sync_readahead(inode->i_mapping, ra,
1521 file, ra_index, cluster);
1522 ra_index += cluster;
1523 }
1524
1525 inode_lock(inode);
1526 if (IS_SWAPFILE(inode)) {
1527 ret = -ETXTBSY;
1528 } else {
1529 if (do_compress)
1530 BTRFS_I(inode)->defrag_compress = compress_type;
1531 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1532 }
1533 if (ret < 0) {
1534 inode_unlock(inode);
1535 goto out_ra;
1536 }
1537
1538 defrag_count += ret;
1539 balance_dirty_pages_ratelimited(inode->i_mapping);
1540 inode_unlock(inode);
1541
1542 if (newer_than) {
1543 if (newer_off == (u64)-1)
1544 break;
1545
1546 if (ret > 0)
1547 i += ret;
1548
1549 newer_off = max(newer_off + 1,
1550 (u64)i << PAGE_SHIFT);
1551
1552 ret = find_new_extents(root, inode, newer_than,
1553 &newer_off, SZ_64K);
1554 if (!ret) {
1555 range->start = newer_off;
1556 i = (newer_off & new_align) >> PAGE_SHIFT;
1557 } else {
1558 break;
1559 }
1560 } else {
1561 if (ret > 0) {
1562 i += ret;
1563 last_len += ret << PAGE_SHIFT;
1564 } else {
1565 i++;
1566 last_len = 0;
1567 }
1568 }
1569 }
1570
1571 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1572 filemap_flush(inode->i_mapping);
1573 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1574 &BTRFS_I(inode)->runtime_flags))
1575 filemap_flush(inode->i_mapping);
1576 }
1577
1578 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1579 btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
1580 } else if (range->compress_type == BTRFS_COMPRESS_ZSTD) {
1581 btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
1582 }
1583
1584 ret = defrag_count;
1585
1586 out_ra:
1587 if (do_compress) {
1588 inode_lock(inode);
1589 BTRFS_I(inode)->defrag_compress = BTRFS_COMPRESS_NONE;
1590 inode_unlock(inode);
1591 }
1592 if (!file)
1593 kfree(ra);
1594 kfree(pages);
1595 return ret;
1596 }
1597
1598 static noinline int btrfs_ioctl_resize(struct file *file,
1599 void __user *arg)
1600 {
1601 struct inode *inode = file_inode(file);
1602 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1603 u64 new_size;
1604 u64 old_size;
1605 u64 devid = 1;
1606 struct btrfs_root *root = BTRFS_I(inode)->root;
1607 struct btrfs_ioctl_vol_args *vol_args;
1608 struct btrfs_trans_handle *trans;
1609 struct btrfs_device *device = NULL;
1610 char *sizestr;
1611 char *retptr;
1612 char *devstr = NULL;
1613 int ret = 0;
1614 int mod = 0;
1615
1616 if (!capable(CAP_SYS_ADMIN))
1617 return -EPERM;
1618
1619 ret = mnt_want_write_file(file);
1620 if (ret)
1621 return ret;
1622
1623 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
1624 mnt_drop_write_file(file);
1625 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1626 }
1627
1628 vol_args = memdup_user(arg, sizeof(*vol_args));
1629 if (IS_ERR(vol_args)) {
1630 ret = PTR_ERR(vol_args);
1631 goto out;
1632 }
1633
1634 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1635
1636 sizestr = vol_args->name;
1637 devstr = strchr(sizestr, ':');
1638 if (devstr) {
1639 sizestr = devstr + 1;
1640 *devstr = '\0';
1641 devstr = vol_args->name;
1642 ret = kstrtoull(devstr, 10, &devid);
1643 if (ret)
1644 goto out_free;
1645 if (!devid) {
1646 ret = -EINVAL;
1647 goto out_free;
1648 }
1649 btrfs_info(fs_info, "resizing devid %llu", devid);
1650 }
1651
1652 device = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
1653 if (!device) {
1654 btrfs_info(fs_info, "resizer unable to find device %llu",
1655 devid);
1656 ret = -ENODEV;
1657 goto out_free;
1658 }
1659
1660 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
1661 btrfs_info(fs_info,
1662 "resizer unable to apply on readonly device %llu",
1663 devid);
1664 ret = -EPERM;
1665 goto out_free;
1666 }
1667
1668 if (!strcmp(sizestr, "max"))
1669 new_size = device->bdev->bd_inode->i_size;
1670 else {
1671 if (sizestr[0] == '-') {
1672 mod = -1;
1673 sizestr++;
1674 } else if (sizestr[0] == '+') {
1675 mod = 1;
1676 sizestr++;
1677 }
1678 new_size = memparse(sizestr, &retptr);
1679 if (*retptr != '\0' || new_size == 0) {
1680 ret = -EINVAL;
1681 goto out_free;
1682 }
1683 }
1684
1685 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
1686 ret = -EPERM;
1687 goto out_free;
1688 }
1689
1690 old_size = btrfs_device_get_total_bytes(device);
1691
1692 if (mod < 0) {
1693 if (new_size > old_size) {
1694 ret = -EINVAL;
1695 goto out_free;
1696 }
1697 new_size = old_size - new_size;
1698 } else if (mod > 0) {
1699 if (new_size > ULLONG_MAX - old_size) {
1700 ret = -ERANGE;
1701 goto out_free;
1702 }
1703 new_size = old_size + new_size;
1704 }
1705
1706 if (new_size < SZ_256M) {
1707 ret = -EINVAL;
1708 goto out_free;
1709 }
1710 if (new_size > device->bdev->bd_inode->i_size) {
1711 ret = -EFBIG;
1712 goto out_free;
1713 }
1714
1715 new_size = round_down(new_size, fs_info->sectorsize);
1716
1717 btrfs_info_in_rcu(fs_info, "new size for %s is %llu",
1718 rcu_str_deref(device->name), new_size);
1719
1720 if (new_size > old_size) {
1721 trans = btrfs_start_transaction(root, 0);
1722 if (IS_ERR(trans)) {
1723 ret = PTR_ERR(trans);
1724 goto out_free;
1725 }
1726 ret = btrfs_grow_device(trans, device, new_size);
1727 btrfs_commit_transaction(trans);
1728 } else if (new_size < old_size) {
1729 ret = btrfs_shrink_device(device, new_size);
1730 } /* equal, nothing need to do */
1731
1732 out_free:
1733 kfree(vol_args);
1734 out:
1735 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
1736 mnt_drop_write_file(file);
1737 return ret;
1738 }
1739
1740 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1741 const char *name, unsigned long fd, int subvol,
1742 u64 *transid, bool readonly,
1743 struct btrfs_qgroup_inherit *inherit)
1744 {
1745 int namelen;
1746 int ret = 0;
1747
1748 if (!S_ISDIR(file_inode(file)->i_mode))
1749 return -ENOTDIR;
1750
1751 ret = mnt_want_write_file(file);
1752 if (ret)
1753 goto out;
1754
1755 namelen = strlen(name);
1756 if (strchr(name, '/')) {
1757 ret = -EINVAL;
1758 goto out_drop_write;
1759 }
1760
1761 if (name[0] == '.' &&
1762 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1763 ret = -EEXIST;
1764 goto out_drop_write;
1765 }
1766
1767 if (subvol) {
1768 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1769 NULL, transid, readonly, inherit);
1770 } else {
1771 struct fd src = fdget(fd);
1772 struct inode *src_inode;
1773 if (!src.file) {
1774 ret = -EINVAL;
1775 goto out_drop_write;
1776 }
1777
1778 src_inode = file_inode(src.file);
1779 if (src_inode->i_sb != file_inode(file)->i_sb) {
1780 btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
1781 "Snapshot src from another FS");
1782 ret = -EXDEV;
1783 } else if (!inode_owner_or_capable(src_inode)) {
1784 /*
1785 * Subvolume creation is not restricted, but snapshots
1786 * are limited to own subvolumes only
1787 */
1788 ret = -EPERM;
1789 } else {
1790 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1791 BTRFS_I(src_inode)->root,
1792 transid, readonly, inherit);
1793 }
1794 fdput(src);
1795 }
1796 out_drop_write:
1797 mnt_drop_write_file(file);
1798 out:
1799 return ret;
1800 }
1801
1802 static noinline int btrfs_ioctl_snap_create(struct file *file,
1803 void __user *arg, int subvol)
1804 {
1805 struct btrfs_ioctl_vol_args *vol_args;
1806 int ret;
1807
1808 if (!S_ISDIR(file_inode(file)->i_mode))
1809 return -ENOTDIR;
1810
1811 vol_args = memdup_user(arg, sizeof(*vol_args));
1812 if (IS_ERR(vol_args))
1813 return PTR_ERR(vol_args);
1814 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1815
1816 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1817 vol_args->fd, subvol,
1818 NULL, false, NULL);
1819
1820 kfree(vol_args);
1821 return ret;
1822 }
1823
1824 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1825 void __user *arg, int subvol)
1826 {
1827 struct btrfs_ioctl_vol_args_v2 *vol_args;
1828 int ret;
1829 u64 transid = 0;
1830 u64 *ptr = NULL;
1831 bool readonly = false;
1832 struct btrfs_qgroup_inherit *inherit = NULL;
1833
1834 if (!S_ISDIR(file_inode(file)->i_mode))
1835 return -ENOTDIR;
1836
1837 vol_args = memdup_user(arg, sizeof(*vol_args));
1838 if (IS_ERR(vol_args))
1839 return PTR_ERR(vol_args);
1840 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1841
1842 if (vol_args->flags &
1843 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1844 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1845 ret = -EOPNOTSUPP;
1846 goto free_args;
1847 }
1848
1849 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1850 ptr = &transid;
1851 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1852 readonly = true;
1853 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1854 if (vol_args->size > PAGE_SIZE) {
1855 ret = -EINVAL;
1856 goto free_args;
1857 }
1858 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1859 if (IS_ERR(inherit)) {
1860 ret = PTR_ERR(inherit);
1861 goto free_args;
1862 }
1863 }
1864
1865 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1866 vol_args->fd, subvol, ptr,
1867 readonly, inherit);
1868 if (ret)
1869 goto free_inherit;
1870
1871 if (ptr && copy_to_user(arg +
1872 offsetof(struct btrfs_ioctl_vol_args_v2,
1873 transid),
1874 ptr, sizeof(*ptr)))
1875 ret = -EFAULT;
1876
1877 free_inherit:
1878 kfree(inherit);
1879 free_args:
1880 kfree(vol_args);
1881 return ret;
1882 }
1883
1884 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1885 void __user *arg)
1886 {
1887 struct inode *inode = file_inode(file);
1888 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1889 struct btrfs_root *root = BTRFS_I(inode)->root;
1890 int ret = 0;
1891 u64 flags = 0;
1892
1893 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)
1894 return -EINVAL;
1895
1896 down_read(&fs_info->subvol_sem);
1897 if (btrfs_root_readonly(root))
1898 flags |= BTRFS_SUBVOL_RDONLY;
1899 up_read(&fs_info->subvol_sem);
1900
1901 if (copy_to_user(arg, &flags, sizeof(flags)))
1902 ret = -EFAULT;
1903
1904 return ret;
1905 }
1906
1907 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1908 void __user *arg)
1909 {
1910 struct inode *inode = file_inode(file);
1911 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1912 struct btrfs_root *root = BTRFS_I(inode)->root;
1913 struct btrfs_trans_handle *trans;
1914 u64 root_flags;
1915 u64 flags;
1916 int ret = 0;
1917
1918 if (!inode_owner_or_capable(inode))
1919 return -EPERM;
1920
1921 ret = mnt_want_write_file(file);
1922 if (ret)
1923 goto out;
1924
1925 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
1926 ret = -EINVAL;
1927 goto out_drop_write;
1928 }
1929
1930 if (copy_from_user(&flags, arg, sizeof(flags))) {
1931 ret = -EFAULT;
1932 goto out_drop_write;
1933 }
1934
1935 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1936 ret = -EINVAL;
1937 goto out_drop_write;
1938 }
1939
1940 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1941 ret = -EOPNOTSUPP;
1942 goto out_drop_write;
1943 }
1944
1945 down_write(&fs_info->subvol_sem);
1946
1947 /* nothing to do */
1948 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1949 goto out_drop_sem;
1950
1951 root_flags = btrfs_root_flags(&root->root_item);
1952 if (flags & BTRFS_SUBVOL_RDONLY) {
1953 btrfs_set_root_flags(&root->root_item,
1954 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1955 } else {
1956 /*
1957 * Block RO -> RW transition if this subvolume is involved in
1958 * send
1959 */
1960 spin_lock(&root->root_item_lock);
1961 if (root->send_in_progress == 0) {
1962 btrfs_set_root_flags(&root->root_item,
1963 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1964 spin_unlock(&root->root_item_lock);
1965 } else {
1966 spin_unlock(&root->root_item_lock);
1967 btrfs_warn(fs_info,
1968 "Attempt to set subvolume %llu read-write during send",
1969 root->root_key.objectid);
1970 ret = -EPERM;
1971 goto out_drop_sem;
1972 }
1973 }
1974
1975 trans = btrfs_start_transaction(root, 1);
1976 if (IS_ERR(trans)) {
1977 ret = PTR_ERR(trans);
1978 goto out_reset;
1979 }
1980
1981 ret = btrfs_update_root(trans, fs_info->tree_root,
1982 &root->root_key, &root->root_item);
1983 if (ret < 0) {
1984 btrfs_end_transaction(trans);
1985 goto out_reset;
1986 }
1987
1988 ret = btrfs_commit_transaction(trans);
1989
1990 out_reset:
1991 if (ret)
1992 btrfs_set_root_flags(&root->root_item, root_flags);
1993 out_drop_sem:
1994 up_write(&fs_info->subvol_sem);
1995 out_drop_write:
1996 mnt_drop_write_file(file);
1997 out:
1998 return ret;
1999 }
2000
2001 static noinline int key_in_sk(struct btrfs_key *key,
2002 struct btrfs_ioctl_search_key *sk)
2003 {
2004 struct btrfs_key test;
2005 int ret;
2006
2007 test.objectid = sk->min_objectid;
2008 test.type = sk->min_type;
2009 test.offset = sk->min_offset;
2010
2011 ret = btrfs_comp_cpu_keys(key, &test);
2012 if (ret < 0)
2013 return 0;
2014
2015 test.objectid = sk->max_objectid;
2016 test.type = sk->max_type;
2017 test.offset = sk->max_offset;
2018
2019 ret = btrfs_comp_cpu_keys(key, &test);
2020 if (ret > 0)
2021 return 0;
2022 return 1;
2023 }
2024
2025 static noinline int copy_to_sk(struct btrfs_path *path,
2026 struct btrfs_key *key,
2027 struct btrfs_ioctl_search_key *sk,
2028 size_t *buf_size,
2029 char __user *ubuf,
2030 unsigned long *sk_offset,
2031 int *num_found)
2032 {
2033 u64 found_transid;
2034 struct extent_buffer *leaf;
2035 struct btrfs_ioctl_search_header sh;
2036 struct btrfs_key test;
2037 unsigned long item_off;
2038 unsigned long item_len;
2039 int nritems;
2040 int i;
2041 int slot;
2042 int ret = 0;
2043
2044 leaf = path->nodes[0];
2045 slot = path->slots[0];
2046 nritems = btrfs_header_nritems(leaf);
2047
2048 if (btrfs_header_generation(leaf) > sk->max_transid) {
2049 i = nritems;
2050 goto advance_key;
2051 }
2052 found_transid = btrfs_header_generation(leaf);
2053
2054 for (i = slot; i < nritems; i++) {
2055 item_off = btrfs_item_ptr_offset(leaf, i);
2056 item_len = btrfs_item_size_nr(leaf, i);
2057
2058 btrfs_item_key_to_cpu(leaf, key, i);
2059 if (!key_in_sk(key, sk))
2060 continue;
2061
2062 if (sizeof(sh) + item_len > *buf_size) {
2063 if (*num_found) {
2064 ret = 1;
2065 goto out;
2066 }
2067
2068 /*
2069 * return one empty item back for v1, which does not
2070 * handle -EOVERFLOW
2071 */
2072
2073 *buf_size = sizeof(sh) + item_len;
2074 item_len = 0;
2075 ret = -EOVERFLOW;
2076 }
2077
2078 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2079 ret = 1;
2080 goto out;
2081 }
2082
2083 sh.objectid = key->objectid;
2084 sh.offset = key->offset;
2085 sh.type = key->type;
2086 sh.len = item_len;
2087 sh.transid = found_transid;
2088
2089 /* copy search result header */
2090 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
2091 ret = -EFAULT;
2092 goto out;
2093 }
2094
2095 *sk_offset += sizeof(sh);
2096
2097 if (item_len) {
2098 char __user *up = ubuf + *sk_offset;
2099 /* copy the item */
2100 if (read_extent_buffer_to_user(leaf, up,
2101 item_off, item_len)) {
2102 ret = -EFAULT;
2103 goto out;
2104 }
2105
2106 *sk_offset += item_len;
2107 }
2108 (*num_found)++;
2109
2110 if (ret) /* -EOVERFLOW from above */
2111 goto out;
2112
2113 if (*num_found >= sk->nr_items) {
2114 ret = 1;
2115 goto out;
2116 }
2117 }
2118 advance_key:
2119 ret = 0;
2120 test.objectid = sk->max_objectid;
2121 test.type = sk->max_type;
2122 test.offset = sk->max_offset;
2123 if (btrfs_comp_cpu_keys(key, &test) >= 0)
2124 ret = 1;
2125 else if (key->offset < (u64)-1)
2126 key->offset++;
2127 else if (key->type < (u8)-1) {
2128 key->offset = 0;
2129 key->type++;
2130 } else if (key->objectid < (u64)-1) {
2131 key->offset = 0;
2132 key->type = 0;
2133 key->objectid++;
2134 } else
2135 ret = 1;
2136 out:
2137 /*
2138 * 0: all items from this leaf copied, continue with next
2139 * 1: * more items can be copied, but unused buffer is too small
2140 * * all items were found
2141 * Either way, it will stops the loop which iterates to the next
2142 * leaf
2143 * -EOVERFLOW: item was to large for buffer
2144 * -EFAULT: could not copy extent buffer back to userspace
2145 */
2146 return ret;
2147 }
2148
2149 static noinline int search_ioctl(struct inode *inode,
2150 struct btrfs_ioctl_search_key *sk,
2151 size_t *buf_size,
2152 char __user *ubuf)
2153 {
2154 struct btrfs_fs_info *info = btrfs_sb(inode->i_sb);
2155 struct btrfs_root *root;
2156 struct btrfs_key key;
2157 struct btrfs_path *path;
2158 int ret;
2159 int num_found = 0;
2160 unsigned long sk_offset = 0;
2161
2162 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2163 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2164 return -EOVERFLOW;
2165 }
2166
2167 path = btrfs_alloc_path();
2168 if (!path)
2169 return -ENOMEM;
2170
2171 if (sk->tree_id == 0) {
2172 /* search the root of the inode that was passed */
2173 root = BTRFS_I(inode)->root;
2174 } else {
2175 key.objectid = sk->tree_id;
2176 key.type = BTRFS_ROOT_ITEM_KEY;
2177 key.offset = (u64)-1;
2178 root = btrfs_read_fs_root_no_name(info, &key);
2179 if (IS_ERR(root)) {
2180 btrfs_free_path(path);
2181 return PTR_ERR(root);
2182 }
2183 }
2184
2185 key.objectid = sk->min_objectid;
2186 key.type = sk->min_type;
2187 key.offset = sk->min_offset;
2188
2189 while (1) {
2190 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2191 if (ret != 0) {
2192 if (ret > 0)
2193 ret = 0;
2194 goto err;
2195 }
2196 ret = copy_to_sk(path, &key, sk, buf_size, ubuf,
2197 &sk_offset, &num_found);
2198 btrfs_release_path(path);
2199 if (ret)
2200 break;
2201
2202 }
2203 if (ret > 0)
2204 ret = 0;
2205 err:
2206 sk->nr_items = num_found;
2207 btrfs_free_path(path);
2208 return ret;
2209 }
2210
2211 static noinline int btrfs_ioctl_tree_search(struct file *file,
2212 void __user *argp)
2213 {
2214 struct btrfs_ioctl_search_args __user *uargs;
2215 struct btrfs_ioctl_search_key sk;
2216 struct inode *inode;
2217 int ret;
2218 size_t buf_size;
2219
2220 if (!capable(CAP_SYS_ADMIN))
2221 return -EPERM;
2222
2223 uargs = (struct btrfs_ioctl_search_args __user *)argp;
2224
2225 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2226 return -EFAULT;
2227
2228 buf_size = sizeof(uargs->buf);
2229
2230 inode = file_inode(file);
2231 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2232
2233 /*
2234 * In the origin implementation an overflow is handled by returning a
2235 * search header with a len of zero, so reset ret.
2236 */
2237 if (ret == -EOVERFLOW)
2238 ret = 0;
2239
2240 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2241 ret = -EFAULT;
2242 return ret;
2243 }
2244
2245 static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2246 void __user *argp)
2247 {
2248 struct btrfs_ioctl_search_args_v2 __user *uarg;
2249 struct btrfs_ioctl_search_args_v2 args;
2250 struct inode *inode;
2251 int ret;
2252 size_t buf_size;
2253 const size_t buf_limit = SZ_16M;
2254
2255 if (!capable(CAP_SYS_ADMIN))
2256 return -EPERM;
2257
2258 /* copy search header and buffer size */
2259 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2260 if (copy_from_user(&args, uarg, sizeof(args)))
2261 return -EFAULT;
2262
2263 buf_size = args.buf_size;
2264
2265 /* limit result size to 16MB */
2266 if (buf_size > buf_limit)
2267 buf_size = buf_limit;
2268
2269 inode = file_inode(file);
2270 ret = search_ioctl(inode, &args.key, &buf_size,
2271 (char __user *)(&uarg->buf[0]));
2272 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2273 ret = -EFAULT;
2274 else if (ret == -EOVERFLOW &&
2275 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2276 ret = -EFAULT;
2277
2278 return ret;
2279 }
2280
2281 /*
2282 * Search INODE_REFs to identify path name of 'dirid' directory
2283 * in a 'tree_id' tree. and sets path name to 'name'.
2284 */
2285 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2286 u64 tree_id, u64 dirid, char *name)
2287 {
2288 struct btrfs_root *root;
2289 struct btrfs_key key;
2290 char *ptr;
2291 int ret = -1;
2292 int slot;
2293 int len;
2294 int total_len = 0;
2295 struct btrfs_inode_ref *iref;
2296 struct extent_buffer *l;
2297 struct btrfs_path *path;
2298
2299 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2300 name[0]='\0';
2301 return 0;
2302 }
2303
2304 path = btrfs_alloc_path();
2305 if (!path)
2306 return -ENOMEM;
2307
2308 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1];
2309
2310 key.objectid = tree_id;
2311 key.type = BTRFS_ROOT_ITEM_KEY;
2312 key.offset = (u64)-1;
2313 root = btrfs_read_fs_root_no_name(info, &key);
2314 if (IS_ERR(root)) {
2315 ret = PTR_ERR(root);
2316 goto out;
2317 }
2318
2319 key.objectid = dirid;
2320 key.type = BTRFS_INODE_REF_KEY;
2321 key.offset = (u64)-1;
2322
2323 while (1) {
2324 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2325 if (ret < 0)
2326 goto out;
2327 else if (ret > 0) {
2328 ret = btrfs_previous_item(root, path, dirid,
2329 BTRFS_INODE_REF_KEY);
2330 if (ret < 0)
2331 goto out;
2332 else if (ret > 0) {
2333 ret = -ENOENT;
2334 goto out;
2335 }
2336 }
2337
2338 l = path->nodes[0];
2339 slot = path->slots[0];
2340 btrfs_item_key_to_cpu(l, &key, slot);
2341
2342 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2343 len = btrfs_inode_ref_name_len(l, iref);
2344 ptr -= len + 1;
2345 total_len += len + 1;
2346 if (ptr < name) {
2347 ret = -ENAMETOOLONG;
2348 goto out;
2349 }
2350
2351 *(ptr + len) = '/';
2352 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2353
2354 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2355 break;
2356
2357 btrfs_release_path(path);
2358 key.objectid = key.offset;
2359 key.offset = (u64)-1;
2360 dirid = key.objectid;
2361 }
2362 memmove(name, ptr, total_len);
2363 name[total_len] = '\0';
2364 ret = 0;
2365 out:
2366 btrfs_free_path(path);
2367 return ret;
2368 }
2369
2370 static int btrfs_search_path_in_tree_user(struct inode *inode,
2371 struct btrfs_ioctl_ino_lookup_user_args *args)
2372 {
2373 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2374 struct super_block *sb = inode->i_sb;
2375 struct btrfs_key upper_limit = BTRFS_I(inode)->location;
2376 u64 treeid = BTRFS_I(inode)->root->root_key.objectid;
2377 u64 dirid = args->dirid;
2378 unsigned long item_off;
2379 unsigned long item_len;
2380 struct btrfs_inode_ref *iref;
2381 struct btrfs_root_ref *rref;
2382 struct btrfs_root *root;
2383 struct btrfs_path *path;
2384 struct btrfs_key key, key2;
2385 struct extent_buffer *leaf;
2386 struct inode *temp_inode;
2387 char *ptr;
2388 int slot;
2389 int len;
2390 int total_len = 0;
2391 int ret;
2392
2393 path = btrfs_alloc_path();
2394 if (!path)
2395 return -ENOMEM;
2396
2397 /*
2398 * If the bottom subvolume does not exist directly under upper_limit,
2399 * construct the path in from the bottom up.
2400 */
2401 if (dirid != upper_limit.objectid) {
2402 ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1];
2403
2404 key.objectid = treeid;
2405 key.type = BTRFS_ROOT_ITEM_KEY;
2406 key.offset = (u64)-1;
2407 root = btrfs_read_fs_root_no_name(fs_info, &key);
2408 if (IS_ERR(root)) {
2409 ret = PTR_ERR(root);
2410 goto out;
2411 }
2412
2413 key.objectid = dirid;
2414 key.type = BTRFS_INODE_REF_KEY;
2415 key.offset = (u64)-1;
2416 while (1) {
2417 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2418 if (ret < 0) {
2419 goto out;
2420 } else if (ret > 0) {
2421 ret = btrfs_previous_item(root, path, dirid,
2422 BTRFS_INODE_REF_KEY);
2423 if (ret < 0) {
2424 goto out;
2425 } else if (ret > 0) {
2426 ret = -ENOENT;
2427 goto out;
2428 }
2429 }
2430
2431 leaf = path->nodes[0];
2432 slot = path->slots[0];
2433 btrfs_item_key_to_cpu(leaf, &key, slot);
2434
2435 iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref);
2436 len = btrfs_inode_ref_name_len(leaf, iref);
2437 ptr -= len + 1;
2438 total_len += len + 1;
2439 if (ptr < args->path) {
2440 ret = -ENAMETOOLONG;
2441 goto out;
2442 }
2443
2444 *(ptr + len) = '/';
2445 read_extent_buffer(leaf, ptr,
2446 (unsigned long)(iref + 1), len);
2447
2448 /* Check the read+exec permission of this directory */
2449 ret = btrfs_previous_item(root, path, dirid,
2450 BTRFS_INODE_ITEM_KEY);
2451 if (ret < 0) {
2452 goto out;
2453 } else if (ret > 0) {
2454 ret = -ENOENT;
2455 goto out;
2456 }
2457
2458 leaf = path->nodes[0];
2459 slot = path->slots[0];
2460 btrfs_item_key_to_cpu(leaf, &key2, slot);
2461 if (key2.objectid != dirid) {
2462 ret = -ENOENT;
2463 goto out;
2464 }
2465
2466 temp_inode = btrfs_iget(sb, &key2, root, NULL);
2467 if (IS_ERR(temp_inode)) {
2468 ret = PTR_ERR(temp_inode);
2469 goto out;
2470 }
2471 ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC);
2472 iput(temp_inode);
2473 if (ret) {
2474 ret = -EACCES;
2475 goto out;
2476 }
2477
2478 if (key.offset == upper_limit.objectid)
2479 break;
2480 if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {
2481 ret = -EACCES;
2482 goto out;
2483 }
2484
2485 btrfs_release_path(path);
2486 key.objectid = key.offset;
2487 key.offset = (u64)-1;
2488 dirid = key.objectid;
2489 }
2490
2491 memmove(args->path, ptr, total_len);
2492 args->path[total_len] = '\0';
2493 btrfs_release_path(path);
2494 }
2495
2496 /* Get the bottom subvolume's name from ROOT_REF */
2497 root = fs_info->tree_root;
2498 key.objectid = treeid;
2499 key.type = BTRFS_ROOT_REF_KEY;
2500 key.offset = args->treeid;
2501 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2502 if (ret < 0) {
2503 goto out;
2504 } else if (ret > 0) {
2505 ret = -ENOENT;
2506 goto out;
2507 }
2508
2509 leaf = path->nodes[0];
2510 slot = path->slots[0];
2511 btrfs_item_key_to_cpu(leaf, &key, slot);
2512
2513 item_off = btrfs_item_ptr_offset(leaf, slot);
2514 item_len = btrfs_item_size_nr(leaf, slot);
2515 /* Check if dirid in ROOT_REF corresponds to passed dirid */
2516 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2517 if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) {
2518 ret = -EINVAL;
2519 goto out;
2520 }
2521
2522 /* Copy subvolume's name */
2523 item_off += sizeof(struct btrfs_root_ref);
2524 item_len -= sizeof(struct btrfs_root_ref);
2525 read_extent_buffer(leaf, args->name, item_off, item_len);
2526 args->name[item_len] = 0;
2527
2528 out:
2529 btrfs_free_path(path);
2530 return ret;
2531 }
2532
2533 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2534 void __user *argp)
2535 {
2536 struct btrfs_ioctl_ino_lookup_args *args;
2537 struct inode *inode;
2538 int ret = 0;
2539
2540 args = memdup_user(argp, sizeof(*args));
2541 if (IS_ERR(args))
2542 return PTR_ERR(args);
2543
2544 inode = file_inode(file);
2545
2546 /*
2547 * Unprivileged query to obtain the containing subvolume root id. The
2548 * path is reset so it's consistent with btrfs_search_path_in_tree.
2549 */
2550 if (args->treeid == 0)
2551 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2552
2553 if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2554 args->name[0] = 0;
2555 goto out;
2556 }
2557
2558 if (!capable(CAP_SYS_ADMIN)) {
2559 ret = -EPERM;
2560 goto out;
2561 }
2562
2563 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2564 args->treeid, args->objectid,
2565 args->name);
2566
2567 out:
2568 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2569 ret = -EFAULT;
2570
2571 kfree(args);
2572 return ret;
2573 }
2574
2575 /*
2576 * Version of ino_lookup ioctl (unprivileged)
2577 *
2578 * The main differences from ino_lookup ioctl are:
2579 *
2580 * 1. Read + Exec permission will be checked using inode_permission() during
2581 * path construction. -EACCES will be returned in case of failure.
2582 * 2. Path construction will be stopped at the inode number which corresponds
2583 * to the fd with which this ioctl is called. If constructed path does not
2584 * exist under fd's inode, -EACCES will be returned.
2585 * 3. The name of bottom subvolume is also searched and filled.
2586 */
2587 static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp)
2588 {
2589 struct btrfs_ioctl_ino_lookup_user_args *args;
2590 struct inode *inode;
2591 int ret;
2592
2593 args = memdup_user(argp, sizeof(*args));
2594 if (IS_ERR(args))
2595 return PTR_ERR(args);
2596
2597 inode = file_inode(file);
2598
2599 if (args->dirid == BTRFS_FIRST_FREE_OBJECTID &&
2600 BTRFS_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) {
2601 /*
2602 * The subvolume does not exist under fd with which this is
2603 * called
2604 */
2605 kfree(args);
2606 return -EACCES;
2607 }
2608
2609 ret = btrfs_search_path_in_tree_user(inode, args);
2610
2611 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2612 ret = -EFAULT;
2613
2614 kfree(args);
2615 return ret;
2616 }
2617
2618 /* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */
2619 static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp)
2620 {
2621 struct btrfs_ioctl_get_subvol_info_args *subvol_info;
2622 struct btrfs_fs_info *fs_info;
2623 struct btrfs_root *root;
2624 struct btrfs_path *path;
2625 struct btrfs_key key;
2626 struct btrfs_root_item *root_item;
2627 struct btrfs_root_ref *rref;
2628 struct extent_buffer *leaf;
2629 unsigned long item_off;
2630 unsigned long item_len;
2631 struct inode *inode;
2632 int slot;
2633 int ret = 0;
2634
2635 path = btrfs_alloc_path();
2636 if (!path)
2637 return -ENOMEM;
2638
2639 subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL);
2640 if (!subvol_info) {
2641 btrfs_free_path(path);
2642 return -ENOMEM;
2643 }
2644
2645 inode = file_inode(file);
2646 fs_info = BTRFS_I(inode)->root->fs_info;
2647
2648 /* Get root_item of inode's subvolume */
2649 key.objectid = BTRFS_I(inode)->root->root_key.objectid;
2650 key.type = BTRFS_ROOT_ITEM_KEY;
2651 key.offset = (u64)-1;
2652 root = btrfs_read_fs_root_no_name(fs_info, &key);
2653 if (IS_ERR(root)) {
2654 ret = PTR_ERR(root);
2655 goto out;
2656 }
2657 root_item = &root->root_item;
2658
2659 subvol_info->treeid = key.objectid;
2660
2661 subvol_info->generation = btrfs_root_generation(root_item);
2662 subvol_info->flags = btrfs_root_flags(root_item);
2663
2664 memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE);
2665 memcpy(subvol_info->parent_uuid, root_item->parent_uuid,
2666 BTRFS_UUID_SIZE);
2667 memcpy(subvol_info->received_uuid, root_item->received_uuid,
2668 BTRFS_UUID_SIZE);
2669
2670 subvol_info->ctransid = btrfs_root_ctransid(root_item);
2671 subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime);
2672 subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime);
2673
2674 subvol_info->otransid = btrfs_root_otransid(root_item);
2675 subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime);
2676 subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime);
2677
2678 subvol_info->stransid = btrfs_root_stransid(root_item);
2679 subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime);
2680 subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime);
2681
2682 subvol_info->rtransid = btrfs_root_rtransid(root_item);
2683 subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime);
2684 subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime);
2685
2686 if (key.objectid != BTRFS_FS_TREE_OBJECTID) {
2687 /* Search root tree for ROOT_BACKREF of this subvolume */
2688 root = fs_info->tree_root;
2689
2690 key.type = BTRFS_ROOT_BACKREF_KEY;
2691 key.offset = 0;
2692 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2693 if (ret < 0) {
2694 goto out;
2695 } else if (path->slots[0] >=
2696 btrfs_header_nritems(path->nodes[0])) {
2697 ret = btrfs_next_leaf(root, path);
2698 if (ret < 0) {
2699 goto out;
2700 } else if (ret > 0) {
2701 ret = -EUCLEAN;
2702 goto out;
2703 }
2704 }
2705
2706 leaf = path->nodes[0];
2707 slot = path->slots[0];
2708 btrfs_item_key_to_cpu(leaf, &key, slot);
2709 if (key.objectid == subvol_info->treeid &&
2710 key.type == BTRFS_ROOT_BACKREF_KEY) {
2711 subvol_info->parent_id = key.offset;
2712
2713 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2714 subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref);
2715
2716 item_off = btrfs_item_ptr_offset(leaf, slot)
2717 + sizeof(struct btrfs_root_ref);
2718 item_len = btrfs_item_size_nr(leaf, slot)
2719 - sizeof(struct btrfs_root_ref);
2720 read_extent_buffer(leaf, subvol_info->name,
2721 item_off, item_len);
2722 } else {
2723 ret = -ENOENT;
2724 goto out;
2725 }
2726 }
2727
2728 if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))
2729 ret = -EFAULT;
2730
2731 out:
2732 btrfs_free_path(path);
2733 kzfree(subvol_info);
2734 return ret;
2735 }
2736
2737 /*
2738 * Return ROOT_REF information of the subvolume containing this inode
2739 * except the subvolume name.
2740 */
2741 static int btrfs_ioctl_get_subvol_rootref(struct file *file, void __user *argp)
2742 {
2743 struct btrfs_ioctl_get_subvol_rootref_args *rootrefs;
2744 struct btrfs_root_ref *rref;
2745 struct btrfs_root *root;
2746 struct btrfs_path *path;
2747 struct btrfs_key key;
2748 struct extent_buffer *leaf;
2749 struct inode *inode;
2750 u64 objectid;
2751 int slot;
2752 int ret;
2753 u8 found;
2754
2755 path = btrfs_alloc_path();
2756 if (!path)
2757 return -ENOMEM;
2758
2759 rootrefs = memdup_user(argp, sizeof(*rootrefs));
2760 if (IS_ERR(rootrefs)) {
2761 btrfs_free_path(path);
2762 return PTR_ERR(rootrefs);
2763 }
2764
2765 inode = file_inode(file);
2766 root = BTRFS_I(inode)->root->fs_info->tree_root;
2767 objectid = BTRFS_I(inode)->root->root_key.objectid;
2768
2769 key.objectid = objectid;
2770 key.type = BTRFS_ROOT_REF_KEY;
2771 key.offset = rootrefs->min_treeid;
2772 found = 0;
2773
2774 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2775 if (ret < 0) {
2776 goto out;
2777 } else if (path->slots[0] >=
2778 btrfs_header_nritems(path->nodes[0])) {
2779 ret = btrfs_next_leaf(root, path);
2780 if (ret < 0) {
2781 goto out;
2782 } else if (ret > 0) {
2783 ret = -EUCLEAN;
2784 goto out;
2785 }
2786 }
2787 while (1) {
2788 leaf = path->nodes[0];
2789 slot = path->slots[0];
2790
2791 btrfs_item_key_to_cpu(leaf, &key, slot);
2792 if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) {
2793 ret = 0;
2794 goto out;
2795 }
2796
2797 if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) {
2798 ret = -EOVERFLOW;
2799 goto out;
2800 }
2801
2802 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2803 rootrefs->rootref[found].treeid = key.offset;
2804 rootrefs->rootref[found].dirid =
2805 btrfs_root_ref_dirid(leaf, rref);
2806 found++;
2807
2808 ret = btrfs_next_item(root, path);
2809 if (ret < 0) {
2810 goto out;
2811 } else if (ret > 0) {
2812 ret = -EUCLEAN;
2813 goto out;
2814 }
2815 }
2816
2817 out:
2818 if (!ret || ret == -EOVERFLOW) {
2819 rootrefs->num_items = found;
2820 /* update min_treeid for next search */
2821 if (found)
2822 rootrefs->min_treeid =
2823 rootrefs->rootref[found - 1].treeid + 1;
2824 if (copy_to_user(argp, rootrefs, sizeof(*rootrefs)))
2825 ret = -EFAULT;
2826 }
2827
2828 kfree(rootrefs);
2829 btrfs_free_path(path);
2830
2831 return ret;
2832 }
2833
2834 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2835 void __user *arg)
2836 {
2837 struct dentry *parent = file->f_path.dentry;
2838 struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb);
2839 struct dentry *dentry;
2840 struct inode *dir = d_inode(parent);
2841 struct inode *inode;
2842 struct btrfs_root *root = BTRFS_I(dir)->root;
2843 struct btrfs_root *dest = NULL;
2844 struct btrfs_ioctl_vol_args *vol_args;
2845 int namelen;
2846 int err = 0;
2847
2848 if (!S_ISDIR(dir->i_mode))
2849 return -ENOTDIR;
2850
2851 vol_args = memdup_user(arg, sizeof(*vol_args));
2852 if (IS_ERR(vol_args))
2853 return PTR_ERR(vol_args);
2854
2855 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2856 namelen = strlen(vol_args->name);
2857 if (strchr(vol_args->name, '/') ||
2858 strncmp(vol_args->name, "..", namelen) == 0) {
2859 err = -EINVAL;
2860 goto out;
2861 }
2862
2863 err = mnt_want_write_file(file);
2864 if (err)
2865 goto out;
2866
2867
2868 err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
2869 if (err == -EINTR)
2870 goto out_drop_write;
2871 dentry = lookup_one_len(vol_args->name, parent, namelen);
2872 if (IS_ERR(dentry)) {
2873 err = PTR_ERR(dentry);
2874 goto out_unlock_dir;
2875 }
2876
2877 if (d_really_is_negative(dentry)) {
2878 err = -ENOENT;
2879 goto out_dput;
2880 }
2881
2882 inode = d_inode(dentry);
2883 dest = BTRFS_I(inode)->root;
2884 if (!capable(CAP_SYS_ADMIN)) {
2885 /*
2886 * Regular user. Only allow this with a special mount
2887 * option, when the user has write+exec access to the
2888 * subvol root, and when rmdir(2) would have been
2889 * allowed.
2890 *
2891 * Note that this is _not_ check that the subvol is
2892 * empty or doesn't contain data that we wouldn't
2893 * otherwise be able to delete.
2894 *
2895 * Users who want to delete empty subvols should try
2896 * rmdir(2).
2897 */
2898 err = -EPERM;
2899 if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))
2900 goto out_dput;
2901
2902 /*
2903 * Do not allow deletion if the parent dir is the same
2904 * as the dir to be deleted. That means the ioctl
2905 * must be called on the dentry referencing the root
2906 * of the subvol, not a random directory contained
2907 * within it.
2908 */
2909 err = -EINVAL;
2910 if (root == dest)
2911 goto out_dput;
2912
2913 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2914 if (err)
2915 goto out_dput;
2916 }
2917
2918 /* check if subvolume may be deleted by a user */
2919 err = btrfs_may_delete(dir, dentry, 1);
2920 if (err)
2921 goto out_dput;
2922
2923 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
2924 err = -EINVAL;
2925 goto out_dput;
2926 }
2927
2928 inode_lock(inode);
2929 err = btrfs_delete_subvolume(dir, dentry);
2930 inode_unlock(inode);
2931 if (!err)
2932 d_delete(dentry);
2933
2934 out_dput:
2935 dput(dentry);
2936 out_unlock_dir:
2937 inode_unlock(dir);
2938 out_drop_write:
2939 mnt_drop_write_file(file);
2940 out:
2941 kfree(vol_args);
2942 return err;
2943 }
2944
2945 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2946 {
2947 struct inode *inode = file_inode(file);
2948 struct btrfs_root *root = BTRFS_I(inode)->root;
2949 struct btrfs_ioctl_defrag_range_args *range;
2950 int ret;
2951
2952 ret = mnt_want_write_file(file);
2953 if (ret)
2954 return ret;
2955
2956 if (btrfs_root_readonly(root)) {
2957 ret = -EROFS;
2958 goto out;
2959 }
2960
2961 switch (inode->i_mode & S_IFMT) {
2962 case S_IFDIR:
2963 if (!capable(CAP_SYS_ADMIN)) {
2964 ret = -EPERM;
2965 goto out;
2966 }
2967 ret = btrfs_defrag_root(root);
2968 break;
2969 case S_IFREG:
2970 /*
2971 * Note that this does not check the file descriptor for write
2972 * access. This prevents defragmenting executables that are
2973 * running and allows defrag on files open in read-only mode.
2974 */
2975 if (!capable(CAP_SYS_ADMIN) &&
2976 inode_permission(inode, MAY_WRITE)) {
2977 ret = -EPERM;
2978 goto out;
2979 }
2980
2981 range = kzalloc(sizeof(*range), GFP_KERNEL);
2982 if (!range) {
2983 ret = -ENOMEM;
2984 goto out;
2985 }
2986
2987 if (argp) {
2988 if (copy_from_user(range, argp,
2989 sizeof(*range))) {
2990 ret = -EFAULT;
2991 kfree(range);
2992 goto out;
2993 }
2994 /* compression requires us to start the IO */
2995 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2996 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2997 range->extent_thresh = (u32)-1;
2998 }
2999 } else {
3000 /* the rest are all set to zero by kzalloc */
3001 range->len = (u64)-1;
3002 }
3003 ret = btrfs_defrag_file(file_inode(file), file,
3004 range, BTRFS_OLDEST_GENERATION, 0);
3005 if (ret > 0)
3006 ret = 0;
3007 kfree(range);
3008 break;
3009 default:
3010 ret = -EINVAL;
3011 }
3012 out:
3013 mnt_drop_write_file(file);
3014 return ret;
3015 }
3016
3017 static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg)
3018 {
3019 struct btrfs_ioctl_vol_args *vol_args;
3020 int ret;
3021
3022 if (!capable(CAP_SYS_ADMIN))
3023 return -EPERM;
3024
3025 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags))
3026 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3027
3028 vol_args = memdup_user(arg, sizeof(*vol_args));
3029 if (IS_ERR(vol_args)) {
3030 ret = PTR_ERR(vol_args);
3031 goto out;
3032 }
3033
3034 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3035 ret = btrfs_init_new_device(fs_info, vol_args->name);
3036
3037 if (!ret)
3038 btrfs_info(fs_info, "disk added %s", vol_args->name);
3039
3040 kfree(vol_args);
3041 out:
3042 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3043 return ret;
3044 }
3045
3046 static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
3047 {
3048 struct inode *inode = file_inode(file);
3049 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3050 struct btrfs_ioctl_vol_args_v2 *vol_args;
3051 int ret;
3052
3053 if (!capable(CAP_SYS_ADMIN))
3054 return -EPERM;
3055
3056 ret = mnt_want_write_file(file);
3057 if (ret)
3058 return ret;
3059
3060 vol_args = memdup_user(arg, sizeof(*vol_args));
3061 if (IS_ERR(vol_args)) {
3062 ret = PTR_ERR(vol_args);
3063 goto err_drop;
3064 }
3065
3066 /* Check for compatibility reject unknown flags */
3067 if (vol_args->flags & ~BTRFS_VOL_ARG_V2_FLAGS_SUPPORTED) {
3068 ret = -EOPNOTSUPP;
3069 goto out;
3070 }
3071
3072 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
3073 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3074 goto out;
3075 }
3076
3077 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
3078 ret = btrfs_rm_device(fs_info, NULL, vol_args->devid);
3079 } else {
3080 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
3081 ret = btrfs_rm_device(fs_info, vol_args->name, 0);
3082 }
3083 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3084
3085 if (!ret) {
3086 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
3087 btrfs_info(fs_info, "device deleted: id %llu",
3088 vol_args->devid);
3089 else
3090 btrfs_info(fs_info, "device deleted: %s",
3091 vol_args->name);
3092 }
3093 out:
3094 kfree(vol_args);
3095 err_drop:
3096 mnt_drop_write_file(file);
3097 return ret;
3098 }
3099
3100 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
3101 {
3102 struct inode *inode = file_inode(file);
3103 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3104 struct btrfs_ioctl_vol_args *vol_args;
3105 int ret;
3106
3107 if (!capable(CAP_SYS_ADMIN))
3108 return -EPERM;
3109
3110 ret = mnt_want_write_file(file);
3111 if (ret)
3112 return ret;
3113
3114 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
3115 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3116 goto out_drop_write;
3117 }
3118
3119 vol_args = memdup_user(arg, sizeof(*vol_args));
3120 if (IS_ERR(vol_args)) {
3121 ret = PTR_ERR(vol_args);
3122 goto out;
3123 }
3124
3125 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3126 ret = btrfs_rm_device(fs_info, vol_args->name, 0);
3127
3128 if (!ret)
3129 btrfs_info(fs_info, "disk deleted %s", vol_args->name);
3130 kfree(vol_args);
3131 out:
3132 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3133 out_drop_write:
3134 mnt_drop_write_file(file);
3135
3136 return ret;
3137 }
3138
3139 static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,
3140 void __user *arg)
3141 {
3142 struct btrfs_ioctl_fs_info_args *fi_args;
3143 struct btrfs_device *device;
3144 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
3145 int ret = 0;
3146
3147 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
3148 if (!fi_args)
3149 return -ENOMEM;
3150
3151 rcu_read_lock();
3152 fi_args->num_devices = fs_devices->num_devices;
3153
3154 list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
3155 if (device->devid > fi_args->max_id)
3156 fi_args->max_id = device->devid;
3157 }
3158 rcu_read_unlock();
3159
3160 memcpy(&fi_args->fsid, fs_devices->fsid, sizeof(fi_args->fsid));
3161 fi_args->nodesize = fs_info->nodesize;
3162 fi_args->sectorsize = fs_info->sectorsize;
3163 fi_args->clone_alignment = fs_info->sectorsize;
3164
3165 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
3166 ret = -EFAULT;
3167
3168 kfree(fi_args);
3169 return ret;
3170 }
3171
3172 static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,
3173 void __user *arg)
3174 {
3175 struct btrfs_ioctl_dev_info_args *di_args;
3176 struct btrfs_device *dev;
3177 int ret = 0;
3178 char *s_uuid = NULL;
3179
3180 di_args = memdup_user(arg, sizeof(*di_args));
3181 if (IS_ERR(di_args))
3182 return PTR_ERR(di_args);
3183
3184 if (!btrfs_is_empty_uuid(di_args->uuid))
3185 s_uuid = di_args->uuid;
3186
3187 rcu_read_lock();
3188 dev = btrfs_find_device(fs_info->fs_devices, di_args->devid, s_uuid,
3189 NULL, true);
3190
3191 if (!dev) {
3192 ret = -ENODEV;
3193 goto out;
3194 }
3195
3196 di_args->devid = dev->devid;
3197 di_args->bytes_used = btrfs_device_get_bytes_used(dev);
3198 di_args->total_bytes = btrfs_device_get_total_bytes(dev);
3199 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
3200 if (dev->name) {
3201 strncpy(di_args->path, rcu_str_deref(dev->name),
3202 sizeof(di_args->path) - 1);
3203 di_args->path[sizeof(di_args->path) - 1] = 0;
3204 } else {
3205 di_args->path[0] = '\0';
3206 }
3207
3208 out:
3209 rcu_read_unlock();
3210 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
3211 ret = -EFAULT;
3212
3213 kfree(di_args);
3214 return ret;
3215 }
3216
3217 static void btrfs_double_extent_unlock(struct inode *inode1, u64 loff1,
3218 struct inode *inode2, u64 loff2, u64 len)
3219 {
3220 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
3221 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
3222 }
3223
3224 static void btrfs_double_extent_lock(struct inode *inode1, u64 loff1,
3225 struct inode *inode2, u64 loff2, u64 len)
3226 {
3227 if (inode1 < inode2) {
3228 swap(inode1, inode2);
3229 swap(loff1, loff2);
3230 } else if (inode1 == inode2 && loff2 < loff1) {
3231 swap(loff1, loff2);
3232 }
3233 lock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
3234 lock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
3235 }
3236
3237 static int btrfs_extent_same_range(struct inode *src, u64 loff, u64 len,
3238 struct inode *dst, u64 dst_loff)
3239 {
3240 int ret;
3241
3242 /*
3243 * Lock destination range to serialize with concurrent readpages() and
3244 * source range to serialize with relocation.
3245 */
3246 btrfs_double_extent_lock(src, loff, dst, dst_loff, len);
3247 ret = btrfs_clone(src, dst, loff, len, len, dst_loff, 1);
3248 btrfs_double_extent_unlock(src, loff, dst, dst_loff, len);
3249
3250 return ret;
3251 }
3252
3253 #define BTRFS_MAX_DEDUPE_LEN SZ_16M
3254
3255 static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
3256 struct inode *dst, u64 dst_loff)
3257 {
3258 int ret;
3259 u64 i, tail_len, chunk_count;
3260 struct btrfs_root *root_dst = BTRFS_I(dst)->root;
3261
3262 spin_lock(&root_dst->root_item_lock);
3263 if (root_dst->send_in_progress) {
3264 btrfs_warn_rl(root_dst->fs_info,
3265 "cannot deduplicate to root %llu while send operations are using it (%d in progress)",
3266 root_dst->root_key.objectid,
3267 root_dst->send_in_progress);
3268 spin_unlock(&root_dst->root_item_lock);
3269 return -EAGAIN;
3270 }
3271 root_dst->dedupe_in_progress++;
3272 spin_unlock(&root_dst->root_item_lock);
3273
3274 tail_len = olen % BTRFS_MAX_DEDUPE_LEN;
3275 chunk_count = div_u64(olen, BTRFS_MAX_DEDUPE_LEN);
3276
3277 for (i = 0; i < chunk_count; i++) {
3278 ret = btrfs_extent_same_range(src, loff, BTRFS_MAX_DEDUPE_LEN,
3279 dst, dst_loff);
3280 if (ret)
3281 goto out;
3282
3283 loff += BTRFS_MAX_DEDUPE_LEN;
3284 dst_loff += BTRFS_MAX_DEDUPE_LEN;
3285 }
3286
3287 if (tail_len > 0)
3288 ret = btrfs_extent_same_range(src, loff, tail_len, dst,
3289 dst_loff);
3290 out:
3291 spin_lock(&root_dst->root_item_lock);
3292 root_dst->dedupe_in_progress--;
3293 spin_unlock(&root_dst->root_item_lock);
3294
3295 return ret;
3296 }
3297
3298 static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3299 struct inode *inode,
3300 u64 endoff,
3301 const u64 destoff,
3302 const u64 olen,
3303 int no_time_update)
3304 {
3305 struct btrfs_root *root = BTRFS_I(inode)->root;
3306 int ret;
3307
3308 inode_inc_iversion(inode);
3309 if (!no_time_update)
3310 inode->i_mtime = inode->i_ctime = current_time(inode);
3311 /*
3312 * We round up to the block size at eof when determining which
3313 * extents to clone above, but shouldn't round up the file size.
3314 */
3315 if (endoff > destoff + olen)
3316 endoff = destoff + olen;
3317 if (endoff > inode->i_size)
3318 btrfs_i_size_write(BTRFS_I(inode), endoff);
3319
3320 ret = btrfs_update_inode(trans, root, inode);
3321 if (ret) {
3322 btrfs_abort_transaction(trans, ret);
3323 btrfs_end_transaction(trans);
3324 goto out;
3325 }
3326 ret = btrfs_end_transaction(trans);
3327 out:
3328 return ret;
3329 }
3330
3331 static void clone_update_extent_map(struct btrfs_inode *inode,
3332 const struct btrfs_trans_handle *trans,
3333 const struct btrfs_path *path,
3334 const u64 hole_offset,
3335 const u64 hole_len)
3336 {
3337 struct extent_map_tree *em_tree = &inode->extent_tree;
3338 struct extent_map *em;
3339 int ret;
3340
3341 em = alloc_extent_map();
3342 if (!em) {
3343 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags);
3344 return;
3345 }
3346
3347 if (path) {
3348 struct btrfs_file_extent_item *fi;
3349
3350 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
3351 struct btrfs_file_extent_item);
3352 btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
3353 em->generation = -1;
3354 if (btrfs_file_extent_type(path->nodes[0], fi) ==
3355 BTRFS_FILE_EXTENT_INLINE)
3356 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3357 &inode->runtime_flags);
3358 } else {
3359 em->start = hole_offset;
3360 em->len = hole_len;
3361 em->ram_bytes = em->len;
3362 em->orig_start = hole_offset;
3363 em->block_start = EXTENT_MAP_HOLE;
3364 em->block_len = 0;
3365 em->orig_block_len = 0;
3366 em->compress_type = BTRFS_COMPRESS_NONE;
3367 em->generation = trans->transid;
3368 }
3369
3370 while (1) {
3371 write_lock(&em_tree->lock);
3372 ret = add_extent_mapping(em_tree, em, 1);
3373 write_unlock(&em_tree->lock);
3374 if (ret != -EEXIST) {
3375 free_extent_map(em);
3376 break;
3377 }
3378 btrfs_drop_extent_cache(inode, em->start,
3379 em->start + em->len - 1, 0);
3380 }
3381
3382 if (ret)
3383 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags);
3384 }
3385
3386 /*
3387 * Make sure we do not end up inserting an inline extent into a file that has
3388 * already other (non-inline) extents. If a file has an inline extent it can
3389 * not have any other extents and the (single) inline extent must start at the
3390 * file offset 0. Failing to respect these rules will lead to file corruption,
3391 * resulting in EIO errors on read/write operations, hitting BUG_ON's in mm, etc
3392 *
3393 * We can have extents that have been already written to disk or we can have
3394 * dirty ranges still in delalloc, in which case the extent maps and items are
3395 * created only when we run delalloc, and the delalloc ranges might fall outside
3396 * the range we are currently locking in the inode's io tree. So we check the
3397 * inode's i_size because of that (i_size updates are done while holding the
3398 * i_mutex, which we are holding here).
3399 * We also check to see if the inode has a size not greater than "datal" but has
3400 * extents beyond it, due to an fallocate with FALLOC_FL_KEEP_SIZE (and we are
3401 * protected against such concurrent fallocate calls by the i_mutex).
3402 *
3403 * If the file has no extents but a size greater than datal, do not allow the
3404 * copy because we would need turn the inline extent into a non-inline one (even
3405 * with NO_HOLES enabled). If we find our destination inode only has one inline
3406 * extent, just overwrite it with the source inline extent if its size is less
3407 * than the source extent's size, or we could copy the source inline extent's
3408 * data into the destination inode's inline extent if the later is greater then
3409 * the former.
3410 */
3411 static int clone_copy_inline_extent(struct inode *dst,
3412 struct btrfs_trans_handle *trans,
3413 struct btrfs_path *path,
3414 struct btrfs_key *new_key,
3415 const u64 drop_start,
3416 const u64 datal,
3417 const u64 skip,
3418 const u64 size,
3419 char *inline_data)
3420 {
3421 struct btrfs_fs_info *fs_info = btrfs_sb(dst->i_sb);
3422 struct btrfs_root *root = BTRFS_I(dst)->root;
3423 const u64 aligned_end = ALIGN(new_key->offset + datal,
3424 fs_info->sectorsize);
3425 int ret;
3426 struct btrfs_key key;
3427
3428 if (new_key->offset > 0)
3429 return -EOPNOTSUPP;
3430
3431 key.objectid = btrfs_ino(BTRFS_I(dst));
3432 key.type = BTRFS_EXTENT_DATA_KEY;
3433 key.offset = 0;
3434 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3435 if (ret < 0) {
3436 return ret;
3437 } else if (ret > 0) {
3438 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
3439 ret = btrfs_next_leaf(root, path);
3440 if (ret < 0)
3441 return ret;
3442 else if (ret > 0)
3443 goto copy_inline_extent;
3444 }
3445 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
3446 if (key.objectid == btrfs_ino(BTRFS_I(dst)) &&
3447 key.type == BTRFS_EXTENT_DATA_KEY) {
3448 ASSERT(key.offset > 0);
3449 return -EOPNOTSUPP;
3450 }
3451 } else if (i_size_read(dst) <= datal) {
3452 struct btrfs_file_extent_item *ei;
3453 u64 ext_len;
3454
3455 /*
3456 * If the file size is <= datal, make sure there are no other
3457 * extents following (can happen do to an fallocate call with
3458 * the flag FALLOC_FL_KEEP_SIZE).
3459 */
3460 ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
3461 struct btrfs_file_extent_item);
3462 /*
3463 * If it's an inline extent, it can not have other extents
3464 * following it.
3465 */
3466 if (btrfs_file_extent_type(path->nodes[0], ei) ==
3467 BTRFS_FILE_EXTENT_INLINE)
3468 goto copy_inline_extent;
3469
3470 ext_len = btrfs_file_extent_num_bytes(path->nodes[0], ei);
3471 if (ext_len > aligned_end)
3472 return -EOPNOTSUPP;
3473
3474 ret = btrfs_next_item(root, path);
3475 if (ret < 0) {
3476 return ret;
3477 } else if (ret == 0) {
3478 btrfs_item_key_to_cpu(path->nodes[0], &key,
3479 path->slots[0]);
3480 if (key.objectid == btrfs_ino(BTRFS_I(dst)) &&
3481 key.type == BTRFS_EXTENT_DATA_KEY)
3482 return -EOPNOTSUPP;
3483 }
3484 }
3485
3486 copy_inline_extent:
3487 /*
3488 * We have no extent items, or we have an extent at offset 0 which may
3489 * or may not be inlined. All these cases are dealt the same way.
3490 */
3491 if (i_size_read(dst) > datal) {
3492 /*
3493 * If the destination inode has an inline extent...
3494 * This would require copying the data from the source inline
3495 * extent into the beginning of the destination's inline extent.
3496 * But this is really complex, both extents can be compressed
3497 * or just one of them, which would require decompressing and
3498 * re-compressing data (which could increase the new compressed
3499 * size, not allowing the compressed data to fit anymore in an
3500 * inline extent).
3501 * So just don't support this case for now (it should be rare,
3502 * we are not really saving space when cloning inline extents).
3503 */
3504 return -EOPNOTSUPP;
3505 }
3506
3507 btrfs_release_path(path);
3508 ret = btrfs_drop_extents(trans, root, dst, drop_start, aligned_end, 1);
3509 if (ret)
3510 return ret;
3511 ret = btrfs_insert_empty_item(trans, root, path, new_key, size);
3512 if (ret)
3513 return ret;
3514
3515 if (skip) {
3516 const u32 start = btrfs_file_extent_calc_inline_size(0);
3517
3518 memmove(inline_data + start, inline_data + start + skip, datal);
3519 }
3520
3521 write_extent_buffer(path->nodes[0], inline_data,
3522 btrfs_item_ptr_offset(path->nodes[0],
3523 path->slots[0]),
3524 size);
3525 inode_add_bytes(dst, datal);
3526
3527 return 0;
3528 }
3529
3530 /**
3531 * btrfs_clone() - clone a range from inode file to another
3532 *
3533 * @src: Inode to clone from
3534 * @inode: Inode to clone to
3535 * @off: Offset within source to start clone from
3536 * @olen: Original length, passed by user, of range to clone
3537 * @olen_aligned: Block-aligned value of olen
3538 * @destoff: Offset within @inode to start clone
3539 * @no_time_update: Whether to update mtime/ctime on the target inode
3540 */
3541 static int btrfs_clone(struct inode *src, struct inode *inode,
3542 const u64 off, const u64 olen, const u64 olen_aligned,
3543 const u64 destoff, int no_time_update)
3544 {
3545 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3546 struct btrfs_root *root = BTRFS_I(inode)->root;
3547 struct btrfs_path *path = NULL;
3548 struct extent_buffer *leaf;
3549 struct btrfs_trans_handle *trans;
3550 char *buf = NULL;
3551 struct btrfs_key key;
3552 u32 nritems;
3553 int slot;
3554 int ret;
3555 const u64 len = olen_aligned;
3556 u64 last_dest_end = destoff;
3557
3558 ret = -ENOMEM;
3559 buf = kvmalloc(fs_info->nodesize, GFP_KERNEL);
3560 if (!buf)
3561 return ret;
3562
3563 path = btrfs_alloc_path();
3564 if (!path) {
3565 kvfree(buf);
3566 return ret;
3567 }
3568
3569 path->reada = READA_FORWARD;
3570 /* clone data */
3571 key.objectid = btrfs_ino(BTRFS_I(src));
3572 key.type = BTRFS_EXTENT_DATA_KEY;
3573 key.offset = off;
3574
3575 while (1) {
3576 u64 next_key_min_offset = key.offset + 1;
3577
3578 /*
3579 * note the key will change type as we walk through the
3580 * tree.
3581 */
3582 path->leave_spinning = 1;
3583 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3584 0, 0);
3585 if (ret < 0)
3586 goto out;
3587 /*
3588 * First search, if no extent item that starts at offset off was
3589 * found but the previous item is an extent item, it's possible
3590 * it might overlap our target range, therefore process it.
3591 */
3592 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3593 btrfs_item_key_to_cpu(path->nodes[0], &key,
3594 path->slots[0] - 1);
3595 if (key.type == BTRFS_EXTENT_DATA_KEY)
3596 path->slots[0]--;
3597 }
3598
3599 nritems = btrfs_header_nritems(path->nodes[0]);
3600 process_slot:
3601 if (path->slots[0] >= nritems) {
3602 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3603 if (ret < 0)
3604 goto out;
3605 if (ret > 0)
3606 break;
3607 nritems = btrfs_header_nritems(path->nodes[0]);
3608 }
3609 leaf = path->nodes[0];
3610 slot = path->slots[0];
3611
3612 btrfs_item_key_to_cpu(leaf, &key, slot);
3613 if (key.type > BTRFS_EXTENT_DATA_KEY ||
3614 key.objectid != btrfs_ino(BTRFS_I(src)))
3615 break;
3616
3617 if (key.type == BTRFS_EXTENT_DATA_KEY) {
3618 struct btrfs_file_extent_item *extent;
3619 int type;
3620 u32 size;
3621 struct btrfs_key new_key;
3622 u64 disko = 0, diskl = 0;
3623 u64 datao = 0, datal = 0;
3624 u8 comp;
3625 u64 drop_start;
3626
3627 extent = btrfs_item_ptr(leaf, slot,
3628 struct btrfs_file_extent_item);
3629 comp = btrfs_file_extent_compression(leaf, extent);
3630 type = btrfs_file_extent_type(leaf, extent);
3631 if (type == BTRFS_FILE_EXTENT_REG ||
3632 type == BTRFS_FILE_EXTENT_PREALLOC) {
3633 disko = btrfs_file_extent_disk_bytenr(leaf,
3634 extent);
3635 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3636 extent);
3637 datao = btrfs_file_extent_offset(leaf, extent);
3638 datal = btrfs_file_extent_num_bytes(leaf,
3639 extent);
3640 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3641 /* take upper bound, may be compressed */
3642 datal = btrfs_file_extent_ram_bytes(leaf,
3643 extent);
3644 }
3645
3646 /*
3647 * The first search might have left us at an extent
3648 * item that ends before our target range's start, can
3649 * happen if we have holes and NO_HOLES feature enabled.
3650 */
3651 if (key.offset + datal <= off) {
3652 path->slots[0]++;
3653 goto process_slot;
3654 } else if (key.offset >= off + len) {
3655 break;
3656 }
3657 next_key_min_offset = key.offset + datal;
3658 size = btrfs_item_size_nr(leaf, slot);
3659 read_extent_buffer(leaf, buf,
3660 btrfs_item_ptr_offset(leaf, slot),
3661 size);
3662
3663 btrfs_release_path(path);
3664 path->leave_spinning = 0;
3665
3666 memcpy(&new_key, &key, sizeof(new_key));
3667 new_key.objectid = btrfs_ino(BTRFS_I(inode));
3668 if (off <= key.offset)
3669 new_key.offset = key.offset + destoff - off;
3670 else
3671 new_key.offset = destoff;
3672
3673 /*
3674 * Deal with a hole that doesn't have an extent item
3675 * that represents it (NO_HOLES feature enabled).
3676 * This hole is either in the middle of the cloning
3677 * range or at the beginning (fully overlaps it or
3678 * partially overlaps it).
3679 */
3680 if (new_key.offset != last_dest_end)
3681 drop_start = last_dest_end;
3682 else
3683 drop_start = new_key.offset;
3684
3685 /*
3686 * 1 - adjusting old extent (we may have to split it)
3687 * 1 - add new extent
3688 * 1 - inode update
3689 */
3690 trans = btrfs_start_transaction(root, 3);
3691 if (IS_ERR(trans)) {
3692 ret = PTR_ERR(trans);
3693 goto out;
3694 }
3695
3696 if (type == BTRFS_FILE_EXTENT_REG ||
3697 type == BTRFS_FILE_EXTENT_PREALLOC) {
3698 /*
3699 * a | --- range to clone ---| b
3700 * | ------------- extent ------------- |
3701 */
3702
3703 /* subtract range b */
3704 if (key.offset + datal > off + len)
3705 datal = off + len - key.offset;
3706
3707 /* subtract range a */
3708 if (off > key.offset) {
3709 datao += off - key.offset;
3710 datal -= off - key.offset;
3711 }
3712
3713 ret = btrfs_drop_extents(trans, root, inode,
3714 drop_start,
3715 new_key.offset + datal,
3716 1);
3717 if (ret) {
3718 if (ret != -EOPNOTSUPP)
3719 btrfs_abort_transaction(trans,
3720 ret);
3721 btrfs_end_transaction(trans);
3722 goto out;
3723 }
3724
3725 ret = btrfs_insert_empty_item(trans, root, path,
3726 &new_key, size);
3727 if (ret) {
3728 btrfs_abort_transaction(trans, ret);
3729 btrfs_end_transaction(trans);
3730 goto out;
3731 }
3732
3733 leaf = path->nodes[0];
3734 slot = path->slots[0];
3735 write_extent_buffer(leaf, buf,
3736 btrfs_item_ptr_offset(leaf, slot),
3737 size);
3738
3739 extent = btrfs_item_ptr(leaf, slot,
3740 struct btrfs_file_extent_item);
3741
3742 /* disko == 0 means it's a hole */
3743 if (!disko)
3744 datao = 0;
3745
3746 btrfs_set_file_extent_offset(leaf, extent,
3747 datao);
3748 btrfs_set_file_extent_num_bytes(leaf, extent,
3749 datal);
3750
3751 if (disko) {
3752 struct btrfs_ref ref = { 0 };
3753 inode_add_bytes(inode, datal);
3754 btrfs_init_generic_ref(&ref,
3755 BTRFS_ADD_DELAYED_REF, disko,
3756 diskl, 0);
3757 btrfs_init_data_ref(&ref,
3758 root->root_key.objectid,
3759 btrfs_ino(BTRFS_I(inode)),
3760 new_key.offset - datao);
3761 ret = btrfs_inc_extent_ref(trans, &ref);
3762 if (ret) {
3763 btrfs_abort_transaction(trans,
3764 ret);
3765 btrfs_end_transaction(trans);
3766 goto out;
3767
3768 }
3769 }
3770 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3771 u64 skip = 0;
3772 u64 trim = 0;
3773
3774 if (off > key.offset) {
3775 skip = off - key.offset;
3776 new_key.offset += skip;
3777 }
3778
3779 if (key.offset + datal > off + len)
3780 trim = key.offset + datal - (off + len);
3781
3782 if (comp && (skip || trim)) {
3783 ret = -EINVAL;
3784 btrfs_end_transaction(trans);
3785 goto out;
3786 }
3787 size -= skip + trim;
3788 datal -= skip + trim;
3789
3790 ret = clone_copy_inline_extent(inode,
3791 trans, path,
3792 &new_key,
3793 drop_start,
3794 datal,
3795 skip, size, buf);
3796 if (ret) {
3797 if (ret != -EOPNOTSUPP)
3798 btrfs_abort_transaction(trans,
3799 ret);
3800 btrfs_end_transaction(trans);
3801 goto out;
3802 }
3803 leaf = path->nodes[0];
3804 slot = path->slots[0];
3805 }
3806
3807 /* If we have an implicit hole (NO_HOLES feature). */
3808 if (drop_start < new_key.offset)
3809 clone_update_extent_map(BTRFS_I(inode), trans,
3810 NULL, drop_start,
3811 new_key.offset - drop_start);
3812
3813 clone_update_extent_map(BTRFS_I(inode), trans,
3814 path, 0, 0);
3815
3816 btrfs_mark_buffer_dirty(leaf);
3817 btrfs_release_path(path);
3818
3819 last_dest_end = ALIGN(new_key.offset + datal,
3820 fs_info->sectorsize);
3821 ret = clone_finish_inode_update(trans, inode,
3822 last_dest_end,
3823 destoff, olen,
3824 no_time_update);
3825 if (ret)
3826 goto out;
3827 if (new_key.offset + datal >= destoff + len)
3828 break;
3829 }
3830 btrfs_release_path(path);
3831 key.offset = next_key_min_offset;
3832
3833 if (fatal_signal_pending(current)) {
3834 ret = -EINTR;
3835 goto out;
3836 }
3837 }
3838 ret = 0;
3839
3840 if (last_dest_end < destoff + len) {
3841 /*
3842 * We have an implicit hole (NO_HOLES feature is enabled) that
3843 * fully or partially overlaps our cloning range at its end.
3844 */
3845 btrfs_release_path(path);
3846
3847 /*
3848 * 1 - remove extent(s)
3849 * 1 - inode update
3850 */
3851 trans = btrfs_start_transaction(root, 2);
3852 if (IS_ERR(trans)) {
3853 ret = PTR_ERR(trans);
3854 goto out;
3855 }
3856 ret = btrfs_drop_extents(trans, root, inode,
3857 last_dest_end, destoff + len, 1);
3858 if (ret) {
3859 if (ret != -EOPNOTSUPP)
3860 btrfs_abort_transaction(trans, ret);
3861 btrfs_end_transaction(trans);
3862 goto out;
3863 }
3864 clone_update_extent_map(BTRFS_I(inode), trans, NULL,
3865 last_dest_end,
3866 destoff + len - last_dest_end);
3867 ret = clone_finish_inode_update(trans, inode, destoff + len,
3868 destoff, olen, no_time_update);
3869 }
3870
3871 out:
3872 btrfs_free_path(path);
3873 kvfree(buf);
3874 return ret;
3875 }
3876
3877 static noinline int btrfs_clone_files(struct file *file, struct file *file_src,
3878 u64 off, u64 olen, u64 destoff)
3879 {
3880 struct inode *inode = file_inode(file);
3881 struct inode *src = file_inode(file_src);
3882 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3883 int ret;
3884 u64 len = olen;
3885 u64 bs = fs_info->sb->s_blocksize;
3886
3887 /*
3888 * TODO:
3889 * - split compressed inline extents. annoying: we need to
3890 * decompress into destination's address_space (the file offset
3891 * may change, so source mapping won't do), then recompress (or
3892 * otherwise reinsert) a subrange.
3893 *
3894 * - split destination inode's inline extents. The inline extents can
3895 * be either compressed or non-compressed.
3896 */
3897
3898 /*
3899 * VFS's generic_remap_file_range_prep() protects us from cloning the
3900 * eof block into the middle of a file, which would result in corruption
3901 * if the file size is not blocksize aligned. So we don't need to check
3902 * for that case here.
3903 */
3904 if (off + len == src->i_size)
3905 len = ALIGN(src->i_size, bs) - off;
3906
3907 if (destoff > inode->i_size) {
3908 const u64 wb_start = ALIGN_DOWN(inode->i_size, bs);
3909
3910 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3911 if (ret)
3912 return ret;
3913 /*
3914 * We may have truncated the last block if the inode's size is
3915 * not sector size aligned, so we need to wait for writeback to
3916 * complete before proceeding further, otherwise we can race
3917 * with cloning and attempt to increment a reference to an
3918 * extent that no longer exists (writeback completed right after
3919 * we found the previous extent covering eof and before we
3920 * attempted to increment its reference count).
3921 */
3922 ret = btrfs_wait_ordered_range(inode, wb_start,
3923 destoff - wb_start);
3924 if (ret)
3925 return ret;
3926 }
3927
3928 /*
3929 * Lock destination range to serialize with concurrent readpages() and
3930 * source range to serialize with relocation.
3931 */
3932 btrfs_double_extent_lock(src, off, inode, destoff, len);
3933 ret = btrfs_clone(src, inode, off, olen, len, destoff, 0);
3934 btrfs_double_extent_unlock(src, off, inode, destoff, len);
3935 /*
3936 * Truncate page cache pages so that future reads will see the cloned
3937 * data immediately and not the previous data.
3938 */
3939 truncate_inode_pages_range(&inode->i_data,
3940 round_down(destoff, PAGE_SIZE),
3941 round_up(destoff + len, PAGE_SIZE) - 1);
3942
3943 return ret;
3944 }
3945
3946 static int btrfs_remap_file_range_prep(struct file *file_in, loff_t pos_in,
3947 struct file *file_out, loff_t pos_out,
3948 loff_t *len, unsigned int remap_flags)
3949 {
3950 struct inode *inode_in = file_inode(file_in);
3951 struct inode *inode_out = file_inode(file_out);
3952 u64 bs = BTRFS_I(inode_out)->root->fs_info->sb->s_blocksize;
3953 bool same_inode = inode_out == inode_in;
3954 u64 wb_len;
3955 int ret;
3956
3957 if (!(remap_flags & REMAP_FILE_DEDUP)) {
3958 struct btrfs_root *root_out = BTRFS_I(inode_out)->root;
3959
3960 if (btrfs_root_readonly(root_out))
3961 return -EROFS;
3962
3963 if (file_in->f_path.mnt != file_out->f_path.mnt ||
3964 inode_in->i_sb != inode_out->i_sb)
3965 return -EXDEV;
3966 }
3967
3968 /* don't make the dst file partly checksummed */
3969 if ((BTRFS_I(inode_in)->flags & BTRFS_INODE_NODATASUM) !=
3970 (BTRFS_I(inode_out)->flags & BTRFS_INODE_NODATASUM)) {
3971 return -EINVAL;
3972 }
3973
3974 /*
3975 * Now that the inodes are locked, we need to start writeback ourselves
3976 * and can not rely on the writeback from the VFS's generic helper
3977 * generic_remap_file_range_prep() because:
3978 *
3979 * 1) For compression we must call filemap_fdatawrite_range() range
3980 * twice (btrfs_fdatawrite_range() does it for us), and the generic
3981 * helper only calls it once;
3982 *
3983 * 2) filemap_fdatawrite_range(), called by the generic helper only
3984 * waits for the writeback to complete, i.e. for IO to be done, and
3985 * not for the ordered extents to complete. We need to wait for them
3986 * to complete so that new file extent items are in the fs tree.
3987 */
3988 if (*len == 0 && !(remap_flags & REMAP_FILE_DEDUP))
3989 wb_len = ALIGN(inode_in->i_size, bs) - ALIGN_DOWN(pos_in, bs);
3990 else
3991 wb_len = ALIGN(*len, bs);
3992
3993 /*
3994 * Since we don't lock ranges, wait for ongoing lockless dio writes (as
3995 * any in progress could create its ordered extents after we wait for
3996 * existing ordered extents below).
3997 */
3998 inode_dio_wait(inode_in);
3999 if (!same_inode)
4000 inode_dio_wait(inode_out);
4001
4002 /*
4003 * Workaround to make sure NOCOW buffered write reach disk as NOCOW.
4004 *
4005 * Btrfs' back references do not have a block level granularity, they
4006 * work at the whole extent level.
4007 * NOCOW buffered write without data space reserved may not be able
4008 * to fall back to CoW due to lack of data space, thus could cause
4009 * data loss.
4010 *
4011 * Here we take a shortcut by flushing the whole inode, so that all
4012 * nocow write should reach disk as nocow before we increase the
4013 * reference of the extent. We could do better by only flushing NOCOW
4014 * data, but that needs extra accounting.
4015 *
4016 * Also we don't need to check ASYNC_EXTENT, as async extent will be
4017 * CoWed anyway, not affecting nocow part.
4018 */
4019 ret = filemap_flush(inode_in->i_mapping);
4020 if (ret < 0)
4021 return ret;
4022
4023 ret = btrfs_wait_ordered_range(inode_in, ALIGN_DOWN(pos_in, bs),
4024 wb_len);
4025 if (ret < 0)
4026 return ret;
4027 ret = btrfs_wait_ordered_range(inode_out, ALIGN_DOWN(pos_out, bs),
4028 wb_len);
4029 if (ret < 0)
4030 return ret;
4031
4032 return generic_remap_file_range_prep(file_in, pos_in, file_out, pos_out,
4033 len, remap_flags);
4034 }
4035
4036 loff_t btrfs_remap_file_range(struct file *src_file, loff_t off,
4037 struct file *dst_file, loff_t destoff, loff_t len,
4038 unsigned int remap_flags)
4039 {
4040 struct inode *src_inode = file_inode(src_file);
4041 struct inode *dst_inode = file_inode(dst_file);
4042 bool same_inode = dst_inode == src_inode;
4043 int ret;
4044
4045 if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY))
4046 return -EINVAL;
4047
4048 if (same_inode)
4049 inode_lock(src_inode);
4050 else
4051 lock_two_nondirectories(src_inode, dst_inode);
4052
4053 ret = btrfs_remap_file_range_prep(src_file, off, dst_file, destoff,
4054 &len, remap_flags);
4055 if (ret < 0 || len == 0)
4056 goto out_unlock;
4057
4058 if (remap_flags & REMAP_FILE_DEDUP)
4059 ret = btrfs_extent_same(src_inode, off, len, dst_inode, destoff);
4060 else
4061 ret = btrfs_clone_files(dst_file, src_file, off, len, destoff);
4062
4063 out_unlock:
4064 if (same_inode)
4065 inode_unlock(src_inode);
4066 else
4067 unlock_two_nondirectories(src_inode, dst_inode);
4068
4069 return ret < 0 ? ret : len;
4070 }
4071
4072 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
4073 {
4074 struct inode *inode = file_inode(file);
4075 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4076 struct btrfs_root *root = BTRFS_I(inode)->root;
4077 struct btrfs_root *new_root;
4078 struct btrfs_dir_item *di;
4079 struct btrfs_trans_handle *trans;
4080 struct btrfs_path *path;
4081 struct btrfs_key location;
4082 struct btrfs_disk_key disk_key;
4083 u64 objectid = 0;
4084 u64 dir_id;
4085 int ret;
4086
4087 if (!capable(CAP_SYS_ADMIN))
4088 return -EPERM;
4089
4090 ret = mnt_want_write_file(file);
4091 if (ret)
4092 return ret;
4093
4094 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
4095 ret = -EFAULT;
4096 goto out;
4097 }
4098
4099 if (!objectid)
4100 objectid = BTRFS_FS_TREE_OBJECTID;
4101
4102 location.objectid = objectid;
4103 location.type = BTRFS_ROOT_ITEM_KEY;
4104 location.offset = (u64)-1;
4105
4106 new_root = btrfs_read_fs_root_no_name(fs_info, &location);
4107 if (IS_ERR(new_root)) {
4108 ret = PTR_ERR(new_root);
4109 goto out;
4110 }
4111 if (!is_fstree(new_root->root_key.objectid)) {
4112 ret = -ENOENT;
4113 goto out;
4114 }
4115
4116 path = btrfs_alloc_path();
4117 if (!path) {
4118 ret = -ENOMEM;
4119 goto out;
4120 }
4121 path->leave_spinning = 1;
4122
4123 trans = btrfs_start_transaction(root, 1);
4124 if (IS_ERR(trans)) {
4125 btrfs_free_path(path);
4126 ret = PTR_ERR(trans);
4127 goto out;
4128 }
4129
4130 dir_id = btrfs_super_root_dir(fs_info->super_copy);
4131 di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
4132 dir_id, "default", 7, 1);
4133 if (IS_ERR_OR_NULL(di)) {
4134 btrfs_free_path(path);
4135 btrfs_end_transaction(trans);
4136 btrfs_err(fs_info,
4137 "Umm, you don't have the default diritem, this isn't going to work");
4138 ret = -ENOENT;
4139 goto out;
4140 }
4141
4142 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
4143 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
4144 btrfs_mark_buffer_dirty(path->nodes[0]);
4145 btrfs_free_path(path);
4146
4147 btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
4148 btrfs_end_transaction(trans);
4149 out:
4150 mnt_drop_write_file(file);
4151 return ret;
4152 }
4153
4154 static void get_block_group_info(struct list_head *groups_list,
4155 struct btrfs_ioctl_space_info *space)
4156 {
4157 struct btrfs_block_group_cache *block_group;
4158
4159 space->total_bytes = 0;
4160 space->used_bytes = 0;
4161 space->flags = 0;
4162 list_for_each_entry(block_group, groups_list, list) {
4163 space->flags = block_group->flags;
4164 space->total_bytes += block_group->key.offset;
4165 space->used_bytes +=
4166 btrfs_block_group_used(&block_group->item);
4167 }
4168 }
4169
4170 static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
4171 void __user *arg)
4172 {
4173 struct btrfs_ioctl_space_args space_args;
4174 struct btrfs_ioctl_space_info space;
4175 struct btrfs_ioctl_space_info *dest;
4176 struct btrfs_ioctl_space_info *dest_orig;
4177 struct btrfs_ioctl_space_info __user *user_dest;
4178 struct btrfs_space_info *info;
4179 static const u64 types[] = {
4180 BTRFS_BLOCK_GROUP_DATA,
4181 BTRFS_BLOCK_GROUP_SYSTEM,
4182 BTRFS_BLOCK_GROUP_METADATA,
4183 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA
4184 };
4185 int num_types = 4;
4186 int alloc_size;
4187 int ret = 0;
4188 u64 slot_count = 0;
4189 int i, c;
4190
4191 if (copy_from_user(&space_args,
4192 (struct btrfs_ioctl_space_args __user *)arg,
4193 sizeof(space_args)))
4194 return -EFAULT;
4195
4196 for (i = 0; i < num_types; i++) {
4197 struct btrfs_space_info *tmp;
4198
4199 info = NULL;
4200 rcu_read_lock();
4201 list_for_each_entry_rcu(tmp, &fs_info->space_info,
4202 list) {
4203 if (tmp->flags == types[i]) {
4204 info = tmp;
4205 break;
4206 }
4207 }
4208 rcu_read_unlock();
4209
4210 if (!info)
4211 continue;
4212
4213 down_read(&info->groups_sem);
4214 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4215 if (!list_empty(&info->block_groups[c]))
4216 slot_count++;
4217 }
4218 up_read(&info->groups_sem);
4219 }
4220
4221 /*
4222 * Global block reserve, exported as a space_info
4223 */
4224 slot_count++;
4225
4226 /* space_slots == 0 means they are asking for a count */
4227 if (space_args.space_slots == 0) {
4228 space_args.total_spaces = slot_count;
4229 goto out;
4230 }
4231
4232 slot_count = min_t(u64, space_args.space_slots, slot_count);
4233
4234 alloc_size = sizeof(*dest) * slot_count;
4235
4236 /* we generally have at most 6 or so space infos, one for each raid
4237 * level. So, a whole page should be more than enough for everyone
4238 */
4239 if (alloc_size > PAGE_SIZE)
4240 return -ENOMEM;
4241
4242 space_args.total_spaces = 0;
4243 dest = kmalloc(alloc_size, GFP_KERNEL);
4244 if (!dest)
4245 return -ENOMEM;
4246 dest_orig = dest;
4247
4248 /* now we have a buffer to copy into */
4249 for (i = 0; i < num_types; i++) {
4250 struct btrfs_space_info *tmp;
4251
4252 if (!slot_count)
4253 break;
4254
4255 info = NULL;
4256 rcu_read_lock();
4257 list_for_each_entry_rcu(tmp, &fs_info->space_info,
4258 list) {
4259 if (tmp->flags == types[i]) {
4260 info = tmp;
4261 break;
4262 }
4263 }
4264 rcu_read_unlock();
4265
4266 if (!info)
4267 continue;
4268 down_read(&info->groups_sem);
4269 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4270 if (!list_empty(&info->block_groups[c])) {
4271 get_block_group_info(&info->block_groups[c],
4272 &space);
4273 memcpy(dest, &space, sizeof(space));
4274 dest++;
4275 space_args.total_spaces++;
4276 slot_count--;
4277 }
4278 if (!slot_count)
4279 break;
4280 }
4281 up_read(&info->groups_sem);
4282 }
4283
4284 /*
4285 * Add global block reserve
4286 */
4287 if (slot_count) {
4288 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
4289
4290 spin_lock(&block_rsv->lock);
4291 space.total_bytes = block_rsv->size;
4292 space.used_bytes = block_rsv->size - block_rsv->reserved;
4293 spin_unlock(&block_rsv->lock);
4294 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
4295 memcpy(dest, &space, sizeof(space));
4296 space_args.total_spaces++;
4297 }
4298
4299 user_dest = (struct btrfs_ioctl_space_info __user *)
4300 (arg + sizeof(struct btrfs_ioctl_space_args));
4301
4302 if (copy_to_user(user_dest, dest_orig, alloc_size))
4303 ret = -EFAULT;
4304
4305 kfree(dest_orig);
4306 out:
4307 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4308 ret = -EFAULT;
4309
4310 return ret;
4311 }
4312
4313 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4314 void __user *argp)
4315 {
4316 struct btrfs_trans_handle *trans;
4317 u64 transid;
4318 int ret;
4319
4320 trans = btrfs_attach_transaction_barrier(root);
4321 if (IS_ERR(trans)) {
4322 if (PTR_ERR(trans) != -ENOENT)
4323 return PTR_ERR(trans);
4324
4325 /* No running transaction, don't bother */
4326 transid = root->fs_info->last_trans_committed;
4327 goto out;
4328 }
4329 transid = trans->transid;
4330 ret = btrfs_commit_transaction_async(trans, 0);
4331 if (ret) {
4332 btrfs_end_transaction(trans);
4333 return ret;
4334 }
4335 out:
4336 if (argp)
4337 if (copy_to_user(argp, &transid, sizeof(transid)))
4338 return -EFAULT;
4339 return 0;
4340 }
4341
4342 static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,
4343 void __user *argp)
4344 {
4345 u64 transid;
4346
4347 if (argp) {
4348 if (copy_from_user(&transid, argp, sizeof(transid)))
4349 return -EFAULT;
4350 } else {
4351 transid = 0; /* current trans */
4352 }
4353 return btrfs_wait_for_commit(fs_info, transid);
4354 }
4355
4356 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4357 {
4358 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
4359 struct btrfs_ioctl_scrub_args *sa;
4360 int ret;
4361
4362 if (!capable(CAP_SYS_ADMIN))
4363 return -EPERM;
4364
4365 sa = memdup_user(arg, sizeof(*sa));
4366 if (IS_ERR(sa))
4367 return PTR_ERR(sa);
4368
4369 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4370 ret = mnt_want_write_file(file);
4371 if (ret)
4372 goto out;
4373 }
4374
4375 ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,
4376 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4377 0);
4378
4379 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
4380 ret = -EFAULT;
4381
4382 if (!(sa->flags & BTRFS_SCRUB_READONLY))
4383 mnt_drop_write_file(file);
4384 out:
4385 kfree(sa);
4386 return ret;
4387 }
4388
4389 static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)
4390 {
4391 if (!capable(CAP_SYS_ADMIN))
4392 return -EPERM;
4393
4394 return btrfs_scrub_cancel(fs_info);
4395 }
4396
4397 static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
4398 void __user *arg)
4399 {
4400 struct btrfs_ioctl_scrub_args *sa;
4401 int ret;
4402
4403 if (!capable(CAP_SYS_ADMIN))
4404 return -EPERM;
4405
4406 sa = memdup_user(arg, sizeof(*sa));
4407 if (IS_ERR(sa))
4408 return PTR_ERR(sa);
4409
4410 ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
4411
4412 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
4413 ret = -EFAULT;
4414
4415 kfree(sa);
4416 return ret;
4417 }
4418
4419 static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
4420 void __user *arg)
4421 {
4422 struct btrfs_ioctl_get_dev_stats *sa;
4423 int ret;
4424
4425 sa = memdup_user(arg, sizeof(*sa));
4426 if (IS_ERR(sa))
4427 return PTR_ERR(sa);
4428
4429 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4430 kfree(sa);
4431 return -EPERM;
4432 }
4433
4434 ret = btrfs_get_dev_stats(fs_info, sa);
4435
4436 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
4437 ret = -EFAULT;
4438
4439 kfree(sa);
4440 return ret;
4441 }
4442
4443 static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
4444 void __user *arg)
4445 {
4446 struct btrfs_ioctl_dev_replace_args *p;
4447 int ret;
4448
4449 if (!capable(CAP_SYS_ADMIN))
4450 return -EPERM;
4451
4452 p = memdup_user(arg, sizeof(*p));
4453 if (IS_ERR(p))
4454 return PTR_ERR(p);
4455
4456 switch (p->cmd) {
4457 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4458 if (sb_rdonly(fs_info->sb)) {
4459 ret = -EROFS;
4460 goto out;
4461 }
4462 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
4463 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4464 } else {
4465 ret = btrfs_dev_replace_by_ioctl(fs_info, p);
4466 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
4467 }
4468 break;
4469 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4470 btrfs_dev_replace_status(fs_info, p);
4471 ret = 0;
4472 break;
4473 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4474 p->result = btrfs_dev_replace_cancel(fs_info);
4475 ret = 0;
4476 break;
4477 default:
4478 ret = -EINVAL;
4479 break;
4480 }
4481
4482 if ((ret == 0 || ret == -ECANCELED) && copy_to_user(arg, p, sizeof(*p)))
4483 ret = -EFAULT;
4484 out:
4485 kfree(p);
4486 return ret;
4487 }
4488
4489 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4490 {
4491 int ret = 0;
4492 int i;
4493 u64 rel_ptr;
4494 int size;
4495 struct btrfs_ioctl_ino_path_args *ipa = NULL;
4496 struct inode_fs_paths *ipath = NULL;
4497 struct btrfs_path *path;
4498
4499 if (!capable(CAP_DAC_READ_SEARCH))
4500 return -EPERM;
4501
4502 path = btrfs_alloc_path();
4503 if (!path) {
4504 ret = -ENOMEM;
4505 goto out;
4506 }
4507
4508 ipa = memdup_user(arg, sizeof(*ipa));
4509 if (IS_ERR(ipa)) {
4510 ret = PTR_ERR(ipa);
4511 ipa = NULL;
4512 goto out;
4513 }
4514
4515 size = min_t(u32, ipa->size, 4096);
4516 ipath = init_ipath(size, root, path);
4517 if (IS_ERR(ipath)) {
4518 ret = PTR_ERR(ipath);
4519 ipath = NULL;
4520 goto out;
4521 }
4522
4523 ret = paths_from_inode(ipa->inum, ipath);
4524 if (ret < 0)
4525 goto out;
4526
4527 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4528 rel_ptr = ipath->fspath->val[i] -
4529 (u64)(unsigned long)ipath->fspath->val;
4530 ipath->fspath->val[i] = rel_ptr;
4531 }
4532
4533 ret = copy_to_user((void __user *)(unsigned long)ipa->fspath,
4534 ipath->fspath, size);
4535 if (ret) {
4536 ret = -EFAULT;
4537 goto out;
4538 }
4539
4540 out:
4541 btrfs_free_path(path);
4542 free_ipath(ipath);
4543 kfree(ipa);
4544
4545 return ret;
4546 }
4547
4548 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4549 {
4550 struct btrfs_data_container *inodes = ctx;
4551 const size_t c = 3 * sizeof(u64);
4552
4553 if (inodes->bytes_left >= c) {
4554 inodes->bytes_left -= c;
4555 inodes->val[inodes->elem_cnt] = inum;
4556 inodes->val[inodes->elem_cnt + 1] = offset;
4557 inodes->val[inodes->elem_cnt + 2] = root;
4558 inodes->elem_cnt += 3;
4559 } else {
4560 inodes->bytes_missing += c - inodes->bytes_left;
4561 inodes->bytes_left = 0;
4562 inodes->elem_missed += 3;
4563 }
4564
4565 return 0;
4566 }
4567
4568 static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,
4569 void __user *arg, int version)
4570 {
4571 int ret = 0;
4572 int size;
4573 struct btrfs_ioctl_logical_ino_args *loi;
4574 struct btrfs_data_container *inodes = NULL;
4575 struct btrfs_path *path = NULL;
4576 bool ignore_offset;
4577
4578 if (!capable(CAP_SYS_ADMIN))
4579 return -EPERM;
4580
4581 loi = memdup_user(arg, sizeof(*loi));
4582 if (IS_ERR(loi))
4583 return PTR_ERR(loi);
4584
4585 if (version == 1) {
4586 ignore_offset = false;
4587 size = min_t(u32, loi->size, SZ_64K);
4588 } else {
4589 /* All reserved bits must be 0 for now */
4590 if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) {
4591 ret = -EINVAL;
4592 goto out_loi;
4593 }
4594 /* Only accept flags we have defined so far */
4595 if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) {
4596 ret = -EINVAL;
4597 goto out_loi;
4598 }
4599 ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET;
4600 size = min_t(u32, loi->size, SZ_16M);
4601 }
4602
4603 path = btrfs_alloc_path();
4604 if (!path) {
4605 ret = -ENOMEM;
4606 goto out;
4607 }
4608
4609 inodes = init_data_container(size);
4610 if (IS_ERR(inodes)) {
4611 ret = PTR_ERR(inodes);
4612 inodes = NULL;
4613 goto out;
4614 }
4615
4616 ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
4617 build_ino_list, inodes, ignore_offset);
4618 if (ret == -EINVAL)
4619 ret = -ENOENT;
4620 if (ret < 0)
4621 goto out;
4622
4623 ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes,
4624 size);
4625 if (ret)
4626 ret = -EFAULT;
4627
4628 out:
4629 btrfs_free_path(path);
4630 kvfree(inodes);
4631 out_loi:
4632 kfree(loi);
4633
4634 return ret;
4635 }
4636
4637 void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info,
4638 struct btrfs_ioctl_balance_args *bargs)
4639 {
4640 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4641
4642 bargs->flags = bctl->flags;
4643
4644 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags))
4645 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4646 if (atomic_read(&fs_info->balance_pause_req))
4647 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4648 if (atomic_read(&fs_info->balance_cancel_req))
4649 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4650
4651 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4652 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4653 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4654
4655 spin_lock(&fs_info->balance_lock);
4656 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4657 spin_unlock(&fs_info->balance_lock);
4658 }
4659
4660 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4661 {
4662 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4663 struct btrfs_fs_info *fs_info = root->fs_info;
4664 struct btrfs_ioctl_balance_args *bargs;
4665 struct btrfs_balance_control *bctl;
4666 bool need_unlock; /* for mut. excl. ops lock */
4667 int ret;
4668
4669 if (!capable(CAP_SYS_ADMIN))
4670 return -EPERM;
4671
4672 ret = mnt_want_write_file(file);
4673 if (ret)
4674 return ret;
4675
4676 again:
4677 if (!test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
4678 mutex_lock(&fs_info->balance_mutex);
4679 need_unlock = true;
4680 goto locked;
4681 }
4682
4683 /*
4684 * mut. excl. ops lock is locked. Three possibilities:
4685 * (1) some other op is running
4686 * (2) balance is running
4687 * (3) balance is paused -- special case (think resume)
4688 */
4689 mutex_lock(&fs_info->balance_mutex);
4690 if (fs_info->balance_ctl) {
4691 /* this is either (2) or (3) */
4692 if (!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4693 mutex_unlock(&fs_info->balance_mutex);
4694 /*
4695 * Lock released to allow other waiters to continue,
4696 * we'll reexamine the status again.
4697 */
4698 mutex_lock(&fs_info->balance_mutex);
4699
4700 if (fs_info->balance_ctl &&
4701 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4702 /* this is (3) */
4703 need_unlock = false;
4704 goto locked;
4705 }
4706
4707 mutex_unlock(&fs_info->balance_mutex);
4708 goto again;
4709 } else {
4710 /* this is (2) */
4711 mutex_unlock(&fs_info->balance_mutex);
4712 ret = -EINPROGRESS;
4713 goto out;
4714 }
4715 } else {
4716 /* this is (1) */
4717 mutex_unlock(&fs_info->balance_mutex);
4718 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4719 goto out;
4720 }
4721
4722 locked:
4723 BUG_ON(!test_bit(BTRFS_FS_EXCL_OP, &fs_info->flags));
4724
4725 if (arg) {
4726 bargs = memdup_user(arg, sizeof(*bargs));
4727 if (IS_ERR(bargs)) {
4728 ret = PTR_ERR(bargs);
4729 goto out_unlock;
4730 }
4731
4732 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4733 if (!fs_info->balance_ctl) {
4734 ret = -ENOTCONN;
4735 goto out_bargs;
4736 }
4737
4738 bctl = fs_info->balance_ctl;
4739 spin_lock(&fs_info->balance_lock);
4740 bctl->flags |= BTRFS_BALANCE_RESUME;
4741 spin_unlock(&fs_info->balance_lock);
4742
4743 goto do_balance;
4744 }
4745 } else {
4746 bargs = NULL;
4747 }
4748
4749 if (fs_info->balance_ctl) {
4750 ret = -EINPROGRESS;
4751 goto out_bargs;
4752 }
4753
4754 bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
4755 if (!bctl) {
4756 ret = -ENOMEM;
4757 goto out_bargs;
4758 }
4759
4760 if (arg) {
4761 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4762 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4763 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4764
4765 bctl->flags = bargs->flags;
4766 } else {
4767 /* balance everything - no filters */
4768 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4769 }
4770
4771 if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
4772 ret = -EINVAL;
4773 goto out_bctl;
4774 }
4775
4776 do_balance:
4777 /*
4778 * Ownership of bctl and filesystem flag BTRFS_FS_EXCL_OP goes to
4779 * btrfs_balance. bctl is freed in reset_balance_state, or, if
4780 * restriper was paused all the way until unmount, in free_fs_info.
4781 * The flag should be cleared after reset_balance_state.
4782 */
4783 need_unlock = false;
4784
4785 ret = btrfs_balance(fs_info, bctl, bargs);
4786 bctl = NULL;
4787
4788 if ((ret == 0 || ret == -ECANCELED) && arg) {
4789 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4790 ret = -EFAULT;
4791 }
4792
4793 out_bctl:
4794 kfree(bctl);
4795 out_bargs:
4796 kfree(bargs);
4797 out_unlock:
4798 mutex_unlock(&fs_info->balance_mutex);
4799 if (need_unlock)
4800 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
4801 out:
4802 mnt_drop_write_file(file);
4803 return ret;
4804 }
4805
4806 static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
4807 {
4808 if (!capable(CAP_SYS_ADMIN))
4809 return -EPERM;
4810
4811 switch (cmd) {
4812 case BTRFS_BALANCE_CTL_PAUSE:
4813 return btrfs_pause_balance(fs_info);
4814 case BTRFS_BALANCE_CTL_CANCEL:
4815 return btrfs_cancel_balance(fs_info);
4816 }
4817
4818 return -EINVAL;
4819 }
4820
4821 static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
4822 void __user *arg)
4823 {
4824 struct btrfs_ioctl_balance_args *bargs;
4825 int ret = 0;
4826
4827 if (!capable(CAP_SYS_ADMIN))
4828 return -EPERM;
4829
4830 mutex_lock(&fs_info->balance_mutex);
4831 if (!fs_info->balance_ctl) {
4832 ret = -ENOTCONN;
4833 goto out;
4834 }
4835
4836 bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
4837 if (!bargs) {
4838 ret = -ENOMEM;
4839 goto out;
4840 }
4841
4842 btrfs_update_ioctl_balance_args(fs_info, bargs);
4843
4844 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4845 ret = -EFAULT;
4846
4847 kfree(bargs);
4848 out:
4849 mutex_unlock(&fs_info->balance_mutex);
4850 return ret;
4851 }
4852
4853 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4854 {
4855 struct inode *inode = file_inode(file);
4856 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4857 struct btrfs_ioctl_quota_ctl_args *sa;
4858 int ret;
4859
4860 if (!capable(CAP_SYS_ADMIN))
4861 return -EPERM;
4862
4863 ret = mnt_want_write_file(file);
4864 if (ret)
4865 return ret;
4866
4867 sa = memdup_user(arg, sizeof(*sa));
4868 if (IS_ERR(sa)) {
4869 ret = PTR_ERR(sa);
4870 goto drop_write;
4871 }
4872
4873 down_write(&fs_info->subvol_sem);
4874
4875 switch (sa->cmd) {
4876 case BTRFS_QUOTA_CTL_ENABLE:
4877 ret = btrfs_quota_enable(fs_info);
4878 break;
4879 case BTRFS_QUOTA_CTL_DISABLE:
4880 ret = btrfs_quota_disable(fs_info);
4881 break;
4882 default:
4883 ret = -EINVAL;
4884 break;
4885 }
4886
4887 kfree(sa);
4888 up_write(&fs_info->subvol_sem);
4889 drop_write:
4890 mnt_drop_write_file(file);
4891 return ret;
4892 }
4893
4894 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4895 {
4896 struct inode *inode = file_inode(file);
4897 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4898 struct btrfs_root *root = BTRFS_I(inode)->root;
4899 struct btrfs_ioctl_qgroup_assign_args *sa;
4900 struct btrfs_trans_handle *trans;
4901 int ret;
4902 int err;
4903
4904 if (!capable(CAP_SYS_ADMIN))
4905 return -EPERM;
4906
4907 ret = mnt_want_write_file(file);
4908 if (ret)
4909 return ret;
4910
4911 sa = memdup_user(arg, sizeof(*sa));
4912 if (IS_ERR(sa)) {
4913 ret = PTR_ERR(sa);
4914 goto drop_write;
4915 }
4916
4917 trans = btrfs_join_transaction(root);
4918 if (IS_ERR(trans)) {
4919 ret = PTR_ERR(trans);
4920 goto out;
4921 }
4922
4923 if (sa->assign) {
4924 ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst);
4925 } else {
4926 ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst);
4927 }
4928
4929 /* update qgroup status and info */
4930 err = btrfs_run_qgroups(trans);
4931 if (err < 0)
4932 btrfs_handle_fs_error(fs_info, err,
4933 "failed to update qgroup status and info");
4934 err = btrfs_end_transaction(trans);
4935 if (err && !ret)
4936 ret = err;
4937
4938 out:
4939 kfree(sa);
4940 drop_write:
4941 mnt_drop_write_file(file);
4942 return ret;
4943 }
4944
4945 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4946 {
4947 struct inode *inode = file_inode(file);
4948 struct btrfs_root *root = BTRFS_I(inode)->root;
4949 struct btrfs_ioctl_qgroup_create_args *sa;
4950 struct btrfs_trans_handle *trans;
4951 int ret;
4952 int err;
4953
4954 if (!capable(CAP_SYS_ADMIN))
4955 return -EPERM;
4956
4957 ret = mnt_want_write_file(file);
4958 if (ret)
4959 return ret;
4960
4961 sa = memdup_user(arg, sizeof(*sa));
4962 if (IS_ERR(sa)) {
4963 ret = PTR_ERR(sa);
4964 goto drop_write;
4965 }
4966
4967 if (!sa->qgroupid) {
4968 ret = -EINVAL;
4969 goto out;
4970 }
4971
4972 trans = btrfs_join_transaction(root);
4973 if (IS_ERR(trans)) {
4974 ret = PTR_ERR(trans);
4975 goto out;
4976 }
4977
4978 if (sa->create) {
4979 ret = btrfs_create_qgroup(trans, sa->qgroupid);
4980 } else {
4981 ret = btrfs_remove_qgroup(trans, sa->qgroupid);
4982 }
4983
4984 err = btrfs_end_transaction(trans);
4985 if (err && !ret)
4986 ret = err;
4987
4988 out:
4989 kfree(sa);
4990 drop_write:
4991 mnt_drop_write_file(file);
4992 return ret;
4993 }
4994
4995 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4996 {
4997 struct inode *inode = file_inode(file);
4998 struct btrfs_root *root = BTRFS_I(inode)->root;
4999 struct btrfs_ioctl_qgroup_limit_args *sa;
5000 struct btrfs_trans_handle *trans;
5001 int ret;
5002 int err;
5003 u64 qgroupid;
5004
5005 if (!capable(CAP_SYS_ADMIN))
5006 return -EPERM;
5007
5008 ret = mnt_want_write_file(file);
5009 if (ret)
5010 return ret;
5011
5012 sa = memdup_user(arg, sizeof(*sa));
5013 if (IS_ERR(sa)) {
5014 ret = PTR_ERR(sa);
5015 goto drop_write;
5016 }
5017
5018 trans = btrfs_join_transaction(root);
5019 if (IS_ERR(trans)) {
5020 ret = PTR_ERR(trans);
5021 goto out;
5022 }
5023
5024 qgroupid = sa->qgroupid;
5025 if (!qgroupid) {
5026 /* take the current subvol as qgroup */
5027 qgroupid = root->root_key.objectid;
5028 }
5029
5030 ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim);
5031
5032 err = btrfs_end_transaction(trans);
5033 if (err && !ret)
5034 ret = err;
5035
5036 out:
5037 kfree(sa);
5038 drop_write:
5039 mnt_drop_write_file(file);
5040 return ret;
5041 }
5042
5043 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
5044 {
5045 struct inode *inode = file_inode(file);
5046 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5047 struct btrfs_ioctl_quota_rescan_args *qsa;
5048 int ret;
5049
5050 if (!capable(CAP_SYS_ADMIN))
5051 return -EPERM;
5052
5053 ret = mnt_want_write_file(file);
5054 if (ret)
5055 return ret;
5056
5057 qsa = memdup_user(arg, sizeof(*qsa));
5058 if (IS_ERR(qsa)) {
5059 ret = PTR_ERR(qsa);
5060 goto drop_write;
5061 }
5062
5063 if (qsa->flags) {
5064 ret = -EINVAL;
5065 goto out;
5066 }
5067
5068 ret = btrfs_qgroup_rescan(fs_info);
5069
5070 out:
5071 kfree(qsa);
5072 drop_write:
5073 mnt_drop_write_file(file);
5074 return ret;
5075 }
5076
5077 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
5078 {
5079 struct inode *inode = file_inode(file);
5080 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5081 struct btrfs_ioctl_quota_rescan_args *qsa;
5082 int ret = 0;
5083
5084 if (!capable(CAP_SYS_ADMIN))
5085 return -EPERM;
5086
5087 qsa = kzalloc(sizeof(*qsa), GFP_KERNEL);
5088 if (!qsa)
5089 return -ENOMEM;
5090
5091 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
5092 qsa->flags = 1;
5093 qsa->progress = fs_info->qgroup_rescan_progress.objectid;
5094 }
5095
5096 if (copy_to_user(arg, qsa, sizeof(*qsa)))
5097 ret = -EFAULT;
5098
5099 kfree(qsa);
5100 return ret;
5101 }
5102
5103 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
5104 {
5105 struct inode *inode = file_inode(file);
5106 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5107
5108 if (!capable(CAP_SYS_ADMIN))
5109 return -EPERM;
5110
5111 return btrfs_qgroup_wait_for_completion(fs_info, true);
5112 }
5113
5114 static long _btrfs_ioctl_set_received_subvol(struct file *file,
5115 struct btrfs_ioctl_received_subvol_args *sa)
5116 {
5117 struct inode *inode = file_inode(file);
5118 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5119 struct btrfs_root *root = BTRFS_I(inode)->root;
5120 struct btrfs_root_item *root_item = &root->root_item;
5121 struct btrfs_trans_handle *trans;
5122 struct timespec64 ct = current_time(inode);
5123 int ret = 0;
5124 int received_uuid_changed;
5125
5126 if (!inode_owner_or_capable(inode))
5127 return -EPERM;
5128
5129 ret = mnt_want_write_file(file);
5130 if (ret < 0)
5131 return ret;
5132
5133 down_write(&fs_info->subvol_sem);
5134
5135 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
5136 ret = -EINVAL;
5137 goto out;
5138 }
5139
5140 if (btrfs_root_readonly(root)) {
5141 ret = -EROFS;
5142 goto out;
5143 }
5144
5145 /*
5146 * 1 - root item
5147 * 2 - uuid items (received uuid + subvol uuid)
5148 */
5149 trans = btrfs_start_transaction(root, 3);
5150 if (IS_ERR(trans)) {
5151 ret = PTR_ERR(trans);
5152 trans = NULL;
5153 goto out;
5154 }
5155
5156 sa->rtransid = trans->transid;
5157 sa->rtime.sec = ct.tv_sec;
5158 sa->rtime.nsec = ct.tv_nsec;
5159
5160 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
5161 BTRFS_UUID_SIZE);
5162 if (received_uuid_changed &&
5163 !btrfs_is_empty_uuid(root_item->received_uuid)) {
5164 ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid,
5165 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5166 root->root_key.objectid);
5167 if (ret && ret != -ENOENT) {
5168 btrfs_abort_transaction(trans, ret);
5169 btrfs_end_transaction(trans);
5170 goto out;
5171 }
5172 }
5173 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
5174 btrfs_set_root_stransid(root_item, sa->stransid);
5175 btrfs_set_root_rtransid(root_item, sa->rtransid);
5176 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
5177 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
5178 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
5179 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
5180
5181 ret = btrfs_update_root(trans, fs_info->tree_root,
5182 &root->root_key, &root->root_item);
5183 if (ret < 0) {
5184 btrfs_end_transaction(trans);
5185 goto out;
5186 }
5187 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
5188 ret = btrfs_uuid_tree_add(trans, sa->uuid,
5189 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5190 root->root_key.objectid);
5191 if (ret < 0 && ret != -EEXIST) {
5192 btrfs_abort_transaction(trans, ret);
5193 btrfs_end_transaction(trans);
5194 goto out;
5195 }
5196 }
5197 ret = btrfs_commit_transaction(trans);
5198 out:
5199 up_write(&fs_info->subvol_sem);
5200 mnt_drop_write_file(file);
5201 return ret;
5202 }
5203
5204 #ifdef CONFIG_64BIT
5205 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
5206 void __user *arg)
5207 {
5208 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
5209 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
5210 int ret = 0;
5211
5212 args32 = memdup_user(arg, sizeof(*args32));
5213 if (IS_ERR(args32))
5214 return PTR_ERR(args32);
5215
5216 args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
5217 if (!args64) {
5218 ret = -ENOMEM;
5219 goto out;
5220 }
5221
5222 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
5223 args64->stransid = args32->stransid;
5224 args64->rtransid = args32->rtransid;
5225 args64->stime.sec = args32->stime.sec;
5226 args64->stime.nsec = args32->stime.nsec;
5227 args64->rtime.sec = args32->rtime.sec;
5228 args64->rtime.nsec = args32->rtime.nsec;
5229 args64->flags = args32->flags;
5230
5231 ret = _btrfs_ioctl_set_received_subvol(file, args64);
5232 if (ret)
5233 goto out;
5234
5235 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
5236 args32->stransid = args64->stransid;
5237 args32->rtransid = args64->rtransid;
5238 args32->stime.sec = args64->stime.sec;
5239 args32->stime.nsec = args64->stime.nsec;
5240 args32->rtime.sec = args64->rtime.sec;
5241 args32->rtime.nsec = args64->rtime.nsec;
5242 args32->flags = args64->flags;
5243
5244 ret = copy_to_user(arg, args32, sizeof(*args32));
5245 if (ret)
5246 ret = -EFAULT;
5247
5248 out:
5249 kfree(args32);
5250 kfree(args64);
5251 return ret;
5252 }
5253 #endif
5254
5255 static long btrfs_ioctl_set_received_subvol(struct file *file,
5256 void __user *arg)
5257 {
5258 struct btrfs_ioctl_received_subvol_args *sa = NULL;
5259 int ret = 0;
5260
5261 sa = memdup_user(arg, sizeof(*sa));
5262 if (IS_ERR(sa))
5263 return PTR_ERR(sa);
5264
5265 ret = _btrfs_ioctl_set_received_subvol(file, sa);
5266
5267 if (ret)
5268 goto out;
5269
5270 ret = copy_to_user(arg, sa, sizeof(*sa));
5271 if (ret)
5272 ret = -EFAULT;
5273
5274 out:
5275 kfree(sa);
5276 return ret;
5277 }
5278
5279 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
5280 {
5281 struct inode *inode = file_inode(file);
5282 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5283 size_t len;
5284 int ret;
5285 char label[BTRFS_LABEL_SIZE];
5286
5287 spin_lock(&fs_info->super_lock);
5288 memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5289 spin_unlock(&fs_info->super_lock);
5290
5291 len = strnlen(label, BTRFS_LABEL_SIZE);
5292
5293 if (len == BTRFS_LABEL_SIZE) {
5294 btrfs_warn(fs_info,
5295 "label is too long, return the first %zu bytes",
5296 --len);
5297 }
5298
5299 ret = copy_to_user(arg, label, len);
5300
5301 return ret ? -EFAULT : 0;
5302 }
5303
5304 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5305 {
5306 struct inode *inode = file_inode(file);
5307 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5308 struct btrfs_root *root = BTRFS_I(inode)->root;
5309 struct btrfs_super_block *super_block = fs_info->super_copy;
5310 struct btrfs_trans_handle *trans;
5311 char label[BTRFS_LABEL_SIZE];
5312 int ret;
5313
5314 if (!capable(CAP_SYS_ADMIN))
5315 return -EPERM;
5316
5317 if (copy_from_user(label, arg, sizeof(label)))
5318 return -EFAULT;
5319
5320 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5321 btrfs_err(fs_info,
5322 "unable to set label with more than %d bytes",
5323 BTRFS_LABEL_SIZE - 1);
5324 return -EINVAL;
5325 }
5326
5327 ret = mnt_want_write_file(file);
5328 if (ret)
5329 return ret;
5330
5331 trans = btrfs_start_transaction(root, 0);
5332 if (IS_ERR(trans)) {
5333 ret = PTR_ERR(trans);
5334 goto out_unlock;
5335 }
5336
5337 spin_lock(&fs_info->super_lock);
5338 strcpy(super_block->label, label);
5339 spin_unlock(&fs_info->super_lock);
5340 ret = btrfs_commit_transaction(trans);
5341
5342 out_unlock:
5343 mnt_drop_write_file(file);
5344 return ret;
5345 }
5346
5347 #define INIT_FEATURE_FLAGS(suffix) \
5348 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5349 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5350 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5351
5352 int btrfs_ioctl_get_supported_features(void __user *arg)
5353 {
5354 static const struct btrfs_ioctl_feature_flags features[3] = {
5355 INIT_FEATURE_FLAGS(SUPP),
5356 INIT_FEATURE_FLAGS(SAFE_SET),
5357 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5358 };
5359
5360 if (copy_to_user(arg, &features, sizeof(features)))
5361 return -EFAULT;
5362
5363 return 0;
5364 }
5365
5366 static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5367 {
5368 struct inode *inode = file_inode(file);
5369 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5370 struct btrfs_super_block *super_block = fs_info->super_copy;
5371 struct btrfs_ioctl_feature_flags features;
5372
5373 features.compat_flags = btrfs_super_compat_flags(super_block);
5374 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5375 features.incompat_flags = btrfs_super_incompat_flags(super_block);
5376
5377 if (copy_to_user(arg, &features, sizeof(features)))
5378 return -EFAULT;
5379
5380 return 0;
5381 }
5382
5383 static int check_feature_bits(struct btrfs_fs_info *fs_info,
5384 enum btrfs_feature_set set,
5385 u64 change_mask, u64 flags, u64 supported_flags,
5386 u64 safe_set, u64 safe_clear)
5387 {
5388 const char *type = btrfs_feature_set_names[set];
5389 char *names;
5390 u64 disallowed, unsupported;
5391 u64 set_mask = flags & change_mask;
5392 u64 clear_mask = ~flags & change_mask;
5393
5394 unsupported = set_mask & ~supported_flags;
5395 if (unsupported) {
5396 names = btrfs_printable_features(set, unsupported);
5397 if (names) {
5398 btrfs_warn(fs_info,
5399 "this kernel does not support the %s feature bit%s",
5400 names, strchr(names, ',') ? "s" : "");
5401 kfree(names);
5402 } else
5403 btrfs_warn(fs_info,
5404 "this kernel does not support %s bits 0x%llx",
5405 type, unsupported);
5406 return -EOPNOTSUPP;
5407 }
5408
5409 disallowed = set_mask & ~safe_set;
5410 if (disallowed) {
5411 names = btrfs_printable_features(set, disallowed);
5412 if (names) {
5413 btrfs_warn(fs_info,
5414 "can't set the %s feature bit%s while mounted",
5415 names, strchr(names, ',') ? "s" : "");
5416 kfree(names);
5417 } else
5418 btrfs_warn(fs_info,
5419 "can't set %s bits 0x%llx while mounted",
5420 type, disallowed);
5421 return -EPERM;
5422 }
5423
5424 disallowed = clear_mask & ~safe_clear;
5425 if (disallowed) {
5426 names = btrfs_printable_features(set, disallowed);
5427 if (names) {
5428 btrfs_warn(fs_info,
5429 "can't clear the %s feature bit%s while mounted",
5430 names, strchr(names, ',') ? "s" : "");
5431 kfree(names);
5432 } else
5433 btrfs_warn(fs_info,
5434 "can't clear %s bits 0x%llx while mounted",
5435 type, disallowed);
5436 return -EPERM;
5437 }
5438
5439 return 0;
5440 }
5441
5442 #define check_feature(fs_info, change_mask, flags, mask_base) \
5443 check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags, \
5444 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
5445 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
5446 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5447
5448 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5449 {
5450 struct inode *inode = file_inode(file);
5451 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5452 struct btrfs_root *root = BTRFS_I(inode)->root;
5453 struct btrfs_super_block *super_block = fs_info->super_copy;
5454 struct btrfs_ioctl_feature_flags flags[2];
5455 struct btrfs_trans_handle *trans;
5456 u64 newflags;
5457 int ret;
5458
5459 if (!capable(CAP_SYS_ADMIN))
5460 return -EPERM;
5461
5462 if (copy_from_user(flags, arg, sizeof(flags)))
5463 return -EFAULT;
5464
5465 /* Nothing to do */
5466 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5467 !flags[0].incompat_flags)
5468 return 0;
5469
5470 ret = check_feature(fs_info, flags[0].compat_flags,
5471 flags[1].compat_flags, COMPAT);
5472 if (ret)
5473 return ret;
5474
5475 ret = check_feature(fs_info, flags[0].compat_ro_flags,
5476 flags[1].compat_ro_flags, COMPAT_RO);
5477 if (ret)
5478 return ret;
5479
5480 ret = check_feature(fs_info, flags[0].incompat_flags,
5481 flags[1].incompat_flags, INCOMPAT);
5482 if (ret)
5483 return ret;
5484
5485 ret = mnt_want_write_file(file);
5486 if (ret)
5487 return ret;
5488
5489 trans = btrfs_start_transaction(root, 0);
5490 if (IS_ERR(trans)) {
5491 ret = PTR_ERR(trans);
5492 goto out_drop_write;
5493 }
5494
5495 spin_lock(&fs_info->super_lock);
5496 newflags = btrfs_super_compat_flags(super_block);
5497 newflags |= flags[0].compat_flags & flags[1].compat_flags;
5498 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5499 btrfs_set_super_compat_flags(super_block, newflags);
5500
5501 newflags = btrfs_super_compat_ro_flags(super_block);
5502 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5503 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5504 btrfs_set_super_compat_ro_flags(super_block, newflags);
5505
5506 newflags = btrfs_super_incompat_flags(super_block);
5507 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5508 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5509 btrfs_set_super_incompat_flags(super_block, newflags);
5510 spin_unlock(&fs_info->super_lock);
5511
5512 ret = btrfs_commit_transaction(trans);
5513 out_drop_write:
5514 mnt_drop_write_file(file);
5515
5516 return ret;
5517 }
5518
5519 static int _btrfs_ioctl_send(struct file *file, void __user *argp, bool compat)
5520 {
5521 struct btrfs_ioctl_send_args *arg;
5522 int ret;
5523
5524 if (compat) {
5525 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
5526 struct btrfs_ioctl_send_args_32 args32;
5527
5528 ret = copy_from_user(&args32, argp, sizeof(args32));
5529 if (ret)
5530 return -EFAULT;
5531 arg = kzalloc(sizeof(*arg), GFP_KERNEL);
5532 if (!arg)
5533 return -ENOMEM;
5534 arg->send_fd = args32.send_fd;
5535 arg->clone_sources_count = args32.clone_sources_count;
5536 arg->clone_sources = compat_ptr(args32.clone_sources);
5537 arg->parent_root = args32.parent_root;
5538 arg->flags = args32.flags;
5539 memcpy(arg->reserved, args32.reserved,
5540 sizeof(args32.reserved));
5541 #else
5542 return -ENOTTY;
5543 #endif
5544 } else {
5545 arg = memdup_user(argp, sizeof(*arg));
5546 if (IS_ERR(arg))
5547 return PTR_ERR(arg);
5548 }
5549 ret = btrfs_ioctl_send(file, arg);
5550 kfree(arg);
5551 return ret;
5552 }
5553
5554 long btrfs_ioctl(struct file *file, unsigned int
5555 cmd, unsigned long arg)
5556 {
5557 struct inode *inode = file_inode(file);
5558 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5559 struct btrfs_root *root = BTRFS_I(inode)->root;
5560 void __user *argp = (void __user *)arg;
5561
5562 switch (cmd) {
5563 case FS_IOC_GETFLAGS:
5564 return btrfs_ioctl_getflags(file, argp);
5565 case FS_IOC_SETFLAGS:
5566 return btrfs_ioctl_setflags(file, argp);
5567 case FS_IOC_GETVERSION:
5568 return btrfs_ioctl_getversion(file, argp);
5569 case FITRIM:
5570 return btrfs_ioctl_fitrim(file, argp);
5571 case BTRFS_IOC_SNAP_CREATE:
5572 return btrfs_ioctl_snap_create(file, argp, 0);
5573 case BTRFS_IOC_SNAP_CREATE_V2:
5574 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5575 case BTRFS_IOC_SUBVOL_CREATE:
5576 return btrfs_ioctl_snap_create(file, argp, 1);
5577 case BTRFS_IOC_SUBVOL_CREATE_V2:
5578 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5579 case BTRFS_IOC_SNAP_DESTROY:
5580 return btrfs_ioctl_snap_destroy(file, argp);
5581 case BTRFS_IOC_SUBVOL_GETFLAGS:
5582 return btrfs_ioctl_subvol_getflags(file, argp);
5583 case BTRFS_IOC_SUBVOL_SETFLAGS:
5584 return btrfs_ioctl_subvol_setflags(file, argp);
5585 case BTRFS_IOC_DEFAULT_SUBVOL:
5586 return btrfs_ioctl_default_subvol(file, argp);
5587 case BTRFS_IOC_DEFRAG:
5588 return btrfs_ioctl_defrag(file, NULL);
5589 case BTRFS_IOC_DEFRAG_RANGE:
5590 return btrfs_ioctl_defrag(file, argp);
5591 case BTRFS_IOC_RESIZE:
5592 return btrfs_ioctl_resize(file, argp);
5593 case BTRFS_IOC_ADD_DEV:
5594 return btrfs_ioctl_add_dev(fs_info, argp);
5595 case BTRFS_IOC_RM_DEV:
5596 return btrfs_ioctl_rm_dev(file, argp);
5597 case BTRFS_IOC_RM_DEV_V2:
5598 return btrfs_ioctl_rm_dev_v2(file, argp);
5599 case BTRFS_IOC_FS_INFO:
5600 return btrfs_ioctl_fs_info(fs_info, argp);
5601 case BTRFS_IOC_DEV_INFO:
5602 return btrfs_ioctl_dev_info(fs_info, argp);
5603 case BTRFS_IOC_BALANCE:
5604 return btrfs_ioctl_balance(file, NULL);
5605 case BTRFS_IOC_TREE_SEARCH:
5606 return btrfs_ioctl_tree_search(file, argp);
5607 case BTRFS_IOC_TREE_SEARCH_V2:
5608 return btrfs_ioctl_tree_search_v2(file, argp);
5609 case BTRFS_IOC_INO_LOOKUP:
5610 return btrfs_ioctl_ino_lookup(file, argp);
5611 case BTRFS_IOC_INO_PATHS:
5612 return btrfs_ioctl_ino_to_path(root, argp);
5613 case BTRFS_IOC_LOGICAL_INO:
5614 return btrfs_ioctl_logical_to_ino(fs_info, argp, 1);
5615 case BTRFS_IOC_LOGICAL_INO_V2:
5616 return btrfs_ioctl_logical_to_ino(fs_info, argp, 2);
5617 case BTRFS_IOC_SPACE_INFO:
5618 return btrfs_ioctl_space_info(fs_info, argp);
5619 case BTRFS_IOC_SYNC: {
5620 int ret;
5621
5622 ret = btrfs_start_delalloc_roots(fs_info, -1);
5623 if (ret)
5624 return ret;
5625 ret = btrfs_sync_fs(inode->i_sb, 1);
5626 /*
5627 * The transaction thread may want to do more work,
5628 * namely it pokes the cleaner kthread that will start
5629 * processing uncleaned subvols.
5630 */
5631 wake_up_process(fs_info->transaction_kthread);
5632 return ret;
5633 }
5634 case BTRFS_IOC_START_SYNC:
5635 return btrfs_ioctl_start_sync(root, argp);
5636 case BTRFS_IOC_WAIT_SYNC:
5637 return btrfs_ioctl_wait_sync(fs_info, argp);
5638 case BTRFS_IOC_SCRUB:
5639 return btrfs_ioctl_scrub(file, argp);
5640 case BTRFS_IOC_SCRUB_CANCEL:
5641 return btrfs_ioctl_scrub_cancel(fs_info);
5642 case BTRFS_IOC_SCRUB_PROGRESS:
5643 return btrfs_ioctl_scrub_progress(fs_info, argp);
5644 case BTRFS_IOC_BALANCE_V2:
5645 return btrfs_ioctl_balance(file, argp);
5646 case BTRFS_IOC_BALANCE_CTL:
5647 return btrfs_ioctl_balance_ctl(fs_info, arg);
5648 case BTRFS_IOC_BALANCE_PROGRESS:
5649 return btrfs_ioctl_balance_progress(fs_info, argp);
5650 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5651 return btrfs_ioctl_set_received_subvol(file, argp);
5652 #ifdef CONFIG_64BIT
5653 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5654 return btrfs_ioctl_set_received_subvol_32(file, argp);
5655 #endif
5656 case BTRFS_IOC_SEND:
5657 return _btrfs_ioctl_send(file, argp, false);
5658 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
5659 case BTRFS_IOC_SEND_32:
5660 return _btrfs_ioctl_send(file, argp, true);
5661 #endif
5662 case BTRFS_IOC_GET_DEV_STATS:
5663 return btrfs_ioctl_get_dev_stats(fs_info, argp);
5664 case BTRFS_IOC_QUOTA_CTL:
5665 return btrfs_ioctl_quota_ctl(file, argp);
5666 case BTRFS_IOC_QGROUP_ASSIGN:
5667 return btrfs_ioctl_qgroup_assign(file, argp);
5668 case BTRFS_IOC_QGROUP_CREATE:
5669 return btrfs_ioctl_qgroup_create(file, argp);
5670 case BTRFS_IOC_QGROUP_LIMIT:
5671 return btrfs_ioctl_qgroup_limit(file, argp);
5672 case BTRFS_IOC_QUOTA_RESCAN:
5673 return btrfs_ioctl_quota_rescan(file, argp);
5674 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5675 return btrfs_ioctl_quota_rescan_status(file, argp);
5676 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5677 return btrfs_ioctl_quota_rescan_wait(file, argp);
5678 case BTRFS_IOC_DEV_REPLACE:
5679 return btrfs_ioctl_dev_replace(fs_info, argp);
5680 case BTRFS_IOC_GET_FSLABEL:
5681 return btrfs_ioctl_get_fslabel(file, argp);
5682 case BTRFS_IOC_SET_FSLABEL:
5683 return btrfs_ioctl_set_fslabel(file, argp);
5684 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5685 return btrfs_ioctl_get_supported_features(argp);
5686 case BTRFS_IOC_GET_FEATURES:
5687 return btrfs_ioctl_get_features(file, argp);
5688 case BTRFS_IOC_SET_FEATURES:
5689 return btrfs_ioctl_set_features(file, argp);
5690 case FS_IOC_FSGETXATTR:
5691 return btrfs_ioctl_fsgetxattr(file, argp);
5692 case FS_IOC_FSSETXATTR:
5693 return btrfs_ioctl_fssetxattr(file, argp);
5694 case BTRFS_IOC_GET_SUBVOL_INFO:
5695 return btrfs_ioctl_get_subvol_info(file, argp);
5696 case BTRFS_IOC_GET_SUBVOL_ROOTREF:
5697 return btrfs_ioctl_get_subvol_rootref(file, argp);
5698 case BTRFS_IOC_INO_LOOKUP_USER:
5699 return btrfs_ioctl_ino_lookup_user(file, argp);
5700 }
5701
5702 return -ENOTTY;
5703 }
5704
5705 #ifdef CONFIG_COMPAT
5706 long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
5707 {
5708 /*
5709 * These all access 32-bit values anyway so no further
5710 * handling is necessary.
5711 */
5712 switch (cmd) {
5713 case FS_IOC32_GETFLAGS:
5714 cmd = FS_IOC_GETFLAGS;
5715 break;
5716 case FS_IOC32_SETFLAGS:
5717 cmd = FS_IOC_SETFLAGS;
5718 break;
5719 case FS_IOC32_GETVERSION:
5720 cmd = FS_IOC_GETVERSION;
5721 break;
5722 }
5723
5724 return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
5725 }
5726 #endif
Linux with added FPC-III support