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UBUNTU: Ubuntu-5.15.0-39.42
[mirror_ubuntu-jammy-kernel.git] / fs / btrfs / ioctl.c
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 <linux/fileattr.h>
30 #include <linux/fsverity.h>
31 #include "ctree.h"
32 #include "disk-io.h"
33 #include "export.h"
34 #include "transaction.h"
35 #include "btrfs_inode.h"
36 #include "print-tree.h"
37 #include "volumes.h"
38 #include "locking.h"
39 #include "backref.h"
40 #include "rcu-string.h"
41 #include "send.h"
42 #include "dev-replace.h"
43 #include "props.h"
44 #include "sysfs.h"
45 #include "qgroup.h"
46 #include "tree-log.h"
47 #include "compression.h"
48 #include "space-info.h"
49 #include "delalloc-space.h"
50 #include "block-group.h"
51
52 #ifdef CONFIG_64BIT
53 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
54 * structures are incorrect, as the timespec structure from userspace
55 * is 4 bytes too small. We define these alternatives here to teach
56 * the kernel about the 32-bit struct packing.
57 */
58 struct btrfs_ioctl_timespec_32 {
59 __u64 sec;
60 __u32 nsec;
61 } __attribute__ ((__packed__));
62
63 struct btrfs_ioctl_received_subvol_args_32 {
64 char uuid[BTRFS_UUID_SIZE]; /* in */
65 __u64 stransid; /* in */
66 __u64 rtransid; /* out */
67 struct btrfs_ioctl_timespec_32 stime; /* in */
68 struct btrfs_ioctl_timespec_32 rtime; /* out */
69 __u64 flags; /* in */
70 __u64 reserved[16]; /* in */
71 } __attribute__ ((__packed__));
72
73 #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
74 struct btrfs_ioctl_received_subvol_args_32)
75 #endif
76
77 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
78 struct btrfs_ioctl_send_args_32 {
79 __s64 send_fd; /* in */
80 __u64 clone_sources_count; /* in */
81 compat_uptr_t clone_sources; /* in */
82 __u64 parent_root; /* in */
83 __u64 flags; /* in */
84 __u64 reserved[4]; /* in */
85 } __attribute__ ((__packed__));
86
87 #define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \
88 struct btrfs_ioctl_send_args_32)
89 #endif
90
91 /* Mask out flags that are inappropriate for the given type of inode. */
92 static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,
93 unsigned int flags)
94 {
95 if (S_ISDIR(inode->i_mode))
96 return flags;
97 else if (S_ISREG(inode->i_mode))
98 return flags & ~FS_DIRSYNC_FL;
99 else
100 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
101 }
102
103 /*
104 * Export internal inode flags to the format expected by the FS_IOC_GETFLAGS
105 * ioctl.
106 */
107 static unsigned int btrfs_inode_flags_to_fsflags(struct btrfs_inode *binode)
108 {
109 unsigned int iflags = 0;
110 u32 flags = binode->flags;
111 u32 ro_flags = binode->ro_flags;
112
113 if (flags & BTRFS_INODE_SYNC)
114 iflags |= FS_SYNC_FL;
115 if (flags & BTRFS_INODE_IMMUTABLE)
116 iflags |= FS_IMMUTABLE_FL;
117 if (flags & BTRFS_INODE_APPEND)
118 iflags |= FS_APPEND_FL;
119 if (flags & BTRFS_INODE_NODUMP)
120 iflags |= FS_NODUMP_FL;
121 if (flags & BTRFS_INODE_NOATIME)
122 iflags |= FS_NOATIME_FL;
123 if (flags & BTRFS_INODE_DIRSYNC)
124 iflags |= FS_DIRSYNC_FL;
125 if (flags & BTRFS_INODE_NODATACOW)
126 iflags |= FS_NOCOW_FL;
127 if (ro_flags & BTRFS_INODE_RO_VERITY)
128 iflags |= FS_VERITY_FL;
129
130 if (flags & BTRFS_INODE_NOCOMPRESS)
131 iflags |= FS_NOCOMP_FL;
132 else if (flags & BTRFS_INODE_COMPRESS)
133 iflags |= FS_COMPR_FL;
134
135 return iflags;
136 }
137
138 /*
139 * Update inode->i_flags based on the btrfs internal flags.
140 */
141 void btrfs_sync_inode_flags_to_i_flags(struct inode *inode)
142 {
143 struct btrfs_inode *binode = BTRFS_I(inode);
144 unsigned int new_fl = 0;
145
146 if (binode->flags & BTRFS_INODE_SYNC)
147 new_fl |= S_SYNC;
148 if (binode->flags & BTRFS_INODE_IMMUTABLE)
149 new_fl |= S_IMMUTABLE;
150 if (binode->flags & BTRFS_INODE_APPEND)
151 new_fl |= S_APPEND;
152 if (binode->flags & BTRFS_INODE_NOATIME)
153 new_fl |= S_NOATIME;
154 if (binode->flags & BTRFS_INODE_DIRSYNC)
155 new_fl |= S_DIRSYNC;
156 if (binode->ro_flags & BTRFS_INODE_RO_VERITY)
157 new_fl |= S_VERITY;
158
159 set_mask_bits(&inode->i_flags,
160 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC |
161 S_VERITY, new_fl);
162 }
163
164 /*
165 * Check if @flags are a supported and valid set of FS_*_FL flags and that
166 * the old and new flags are not conflicting
167 */
168 static int check_fsflags(unsigned int old_flags, 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 /* COMPR and NOCOMP on new/old are valid */
178 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
179 return -EINVAL;
180
181 if ((flags & FS_COMPR_FL) && (flags & FS_NOCOW_FL))
182 return -EINVAL;
183
184 /* NOCOW and compression options are mutually exclusive */
185 if ((old_flags & FS_NOCOW_FL) && (flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
186 return -EINVAL;
187 if ((flags & FS_NOCOW_FL) && (old_flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
188 return -EINVAL;
189
190 return 0;
191 }
192
193 static int check_fsflags_compatible(struct btrfs_fs_info *fs_info,
194 unsigned int flags)
195 {
196 if (btrfs_is_zoned(fs_info) && (flags & FS_NOCOW_FL))
197 return -EPERM;
198
199 return 0;
200 }
201
202 /*
203 * Set flags/xflags from the internal inode flags. The remaining items of
204 * fsxattr are zeroed.
205 */
206 int btrfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
207 {
208 struct btrfs_inode *binode = BTRFS_I(d_inode(dentry));
209
210 fileattr_fill_flags(fa, btrfs_inode_flags_to_fsflags(binode));
211 return 0;
212 }
213
214 int btrfs_fileattr_set(struct user_namespace *mnt_userns,
215 struct dentry *dentry, struct fileattr *fa)
216 {
217 struct inode *inode = d_inode(dentry);
218 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
219 struct btrfs_inode *binode = BTRFS_I(inode);
220 struct btrfs_root *root = binode->root;
221 struct btrfs_trans_handle *trans;
222 unsigned int fsflags, old_fsflags;
223 int ret;
224 const char *comp = NULL;
225 u32 binode_flags;
226
227 if (btrfs_root_readonly(root))
228 return -EROFS;
229
230 if (fileattr_has_fsx(fa))
231 return -EOPNOTSUPP;
232
233 fsflags = btrfs_mask_fsflags_for_type(inode, fa->flags);
234 old_fsflags = btrfs_inode_flags_to_fsflags(binode);
235 ret = check_fsflags(old_fsflags, fsflags);
236 if (ret)
237 return ret;
238
239 ret = check_fsflags_compatible(fs_info, fsflags);
240 if (ret)
241 return ret;
242
243 binode_flags = binode->flags;
244 if (fsflags & FS_SYNC_FL)
245 binode_flags |= BTRFS_INODE_SYNC;
246 else
247 binode_flags &= ~BTRFS_INODE_SYNC;
248 if (fsflags & FS_IMMUTABLE_FL)
249 binode_flags |= BTRFS_INODE_IMMUTABLE;
250 else
251 binode_flags &= ~BTRFS_INODE_IMMUTABLE;
252 if (fsflags & FS_APPEND_FL)
253 binode_flags |= BTRFS_INODE_APPEND;
254 else
255 binode_flags &= ~BTRFS_INODE_APPEND;
256 if (fsflags & FS_NODUMP_FL)
257 binode_flags |= BTRFS_INODE_NODUMP;
258 else
259 binode_flags &= ~BTRFS_INODE_NODUMP;
260 if (fsflags & FS_NOATIME_FL)
261 binode_flags |= BTRFS_INODE_NOATIME;
262 else
263 binode_flags &= ~BTRFS_INODE_NOATIME;
264
265 /* If coming from FS_IOC_FSSETXATTR then skip unconverted flags */
266 if (!fa->flags_valid) {
267 /* 1 item for the inode */
268 trans = btrfs_start_transaction(root, 1);
269 if (IS_ERR(trans))
270 return PTR_ERR(trans);
271 goto update_flags;
272 }
273
274 if (fsflags & FS_DIRSYNC_FL)
275 binode_flags |= BTRFS_INODE_DIRSYNC;
276 else
277 binode_flags &= ~BTRFS_INODE_DIRSYNC;
278 if (fsflags & FS_NOCOW_FL) {
279 if (S_ISREG(inode->i_mode)) {
280 /*
281 * It's safe to turn csums off here, no extents exist.
282 * Otherwise we want the flag to reflect the real COW
283 * status of the file and will not set it.
284 */
285 if (inode->i_size == 0)
286 binode_flags |= BTRFS_INODE_NODATACOW |
287 BTRFS_INODE_NODATASUM;
288 } else {
289 binode_flags |= BTRFS_INODE_NODATACOW;
290 }
291 } else {
292 /*
293 * Revert back under same assumptions as above
294 */
295 if (S_ISREG(inode->i_mode)) {
296 if (inode->i_size == 0)
297 binode_flags &= ~(BTRFS_INODE_NODATACOW |
298 BTRFS_INODE_NODATASUM);
299 } else {
300 binode_flags &= ~BTRFS_INODE_NODATACOW;
301 }
302 }
303
304 /*
305 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
306 * flag may be changed automatically if compression code won't make
307 * things smaller.
308 */
309 if (fsflags & FS_NOCOMP_FL) {
310 binode_flags &= ~BTRFS_INODE_COMPRESS;
311 binode_flags |= BTRFS_INODE_NOCOMPRESS;
312 } else if (fsflags & FS_COMPR_FL) {
313
314 if (IS_SWAPFILE(inode))
315 return -ETXTBSY;
316
317 binode_flags |= BTRFS_INODE_COMPRESS;
318 binode_flags &= ~BTRFS_INODE_NOCOMPRESS;
319
320 comp = btrfs_compress_type2str(fs_info->compress_type);
321 if (!comp || comp[0] == 0)
322 comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);
323 } else {
324 binode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
325 }
326
327 /*
328 * 1 for inode item
329 * 2 for properties
330 */
331 trans = btrfs_start_transaction(root, 3);
332 if (IS_ERR(trans))
333 return PTR_ERR(trans);
334
335 if (comp) {
336 ret = btrfs_set_prop(trans, inode, "btrfs.compression", comp,
337 strlen(comp), 0);
338 if (ret) {
339 btrfs_abort_transaction(trans, ret);
340 goto out_end_trans;
341 }
342 } else {
343 ret = btrfs_set_prop(trans, inode, "btrfs.compression", NULL,
344 0, 0);
345 if (ret && ret != -ENODATA) {
346 btrfs_abort_transaction(trans, ret);
347 goto out_end_trans;
348 }
349 }
350
351 update_flags:
352 binode->flags = binode_flags;
353 btrfs_sync_inode_flags_to_i_flags(inode);
354 inode_inc_iversion(inode);
355 inode->i_ctime = current_time(inode);
356 ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
357
358 out_end_trans:
359 btrfs_end_transaction(trans);
360 return ret;
361 }
362
363 /*
364 * Start exclusive operation @type, return true on success
365 */
366 bool btrfs_exclop_start(struct btrfs_fs_info *fs_info,
367 enum btrfs_exclusive_operation type)
368 {
369 bool ret = false;
370
371 spin_lock(&fs_info->super_lock);
372 if (fs_info->exclusive_operation == BTRFS_EXCLOP_NONE) {
373 fs_info->exclusive_operation = type;
374 ret = true;
375 }
376 spin_unlock(&fs_info->super_lock);
377
378 return ret;
379 }
380
381 /*
382 * Conditionally allow to enter the exclusive operation in case it's compatible
383 * with the running one. This must be paired with btrfs_exclop_start_unlock and
384 * btrfs_exclop_finish.
385 *
386 * Compatibility:
387 * - the same type is already running
388 * - not BTRFS_EXCLOP_NONE - this is intentionally incompatible and the caller
389 * must check the condition first that would allow none -> @type
390 */
391 bool btrfs_exclop_start_try_lock(struct btrfs_fs_info *fs_info,
392 enum btrfs_exclusive_operation type)
393 {
394 spin_lock(&fs_info->super_lock);
395 if (fs_info->exclusive_operation == type)
396 return true;
397
398 spin_unlock(&fs_info->super_lock);
399 return false;
400 }
401
402 void btrfs_exclop_start_unlock(struct btrfs_fs_info *fs_info)
403 {
404 spin_unlock(&fs_info->super_lock);
405 }
406
407 void btrfs_exclop_finish(struct btrfs_fs_info *fs_info)
408 {
409 spin_lock(&fs_info->super_lock);
410 WRITE_ONCE(fs_info->exclusive_operation, BTRFS_EXCLOP_NONE);
411 spin_unlock(&fs_info->super_lock);
412 sysfs_notify(&fs_info->fs_devices->fsid_kobj, NULL, "exclusive_operation");
413 }
414
415 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
416 {
417 struct inode *inode = file_inode(file);
418
419 return put_user(inode->i_generation, arg);
420 }
421
422 static noinline int btrfs_ioctl_fitrim(struct btrfs_fs_info *fs_info,
423 void __user *arg)
424 {
425 struct btrfs_device *device;
426 struct request_queue *q;
427 struct fstrim_range range;
428 u64 minlen = ULLONG_MAX;
429 u64 num_devices = 0;
430 int ret;
431
432 if (!capable(CAP_SYS_ADMIN))
433 return -EPERM;
434
435 /*
436 * btrfs_trim_block_group() depends on space cache, which is not
437 * available in zoned filesystem. So, disallow fitrim on a zoned
438 * filesystem for now.
439 */
440 if (btrfs_is_zoned(fs_info))
441 return -EOPNOTSUPP;
442
443 /*
444 * If the fs is mounted with nologreplay, which requires it to be
445 * mounted in RO mode as well, we can not allow discard on free space
446 * inside block groups, because log trees refer to extents that are not
447 * pinned in a block group's free space cache (pinning the extents is
448 * precisely the first phase of replaying a log tree).
449 */
450 if (btrfs_test_opt(fs_info, NOLOGREPLAY))
451 return -EROFS;
452
453 rcu_read_lock();
454 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
455 dev_list) {
456 if (!device->bdev)
457 continue;
458 q = bdev_get_queue(device->bdev);
459 if (blk_queue_discard(q)) {
460 num_devices++;
461 minlen = min_t(u64, q->limits.discard_granularity,
462 minlen);
463 }
464 }
465 rcu_read_unlock();
466
467 if (!num_devices)
468 return -EOPNOTSUPP;
469 if (copy_from_user(&range, arg, sizeof(range)))
470 return -EFAULT;
471
472 /*
473 * NOTE: Don't truncate the range using super->total_bytes. Bytenr of
474 * block group is in the logical address space, which can be any
475 * sectorsize aligned bytenr in the range [0, U64_MAX].
476 */
477 if (range.len < fs_info->sb->s_blocksize)
478 return -EINVAL;
479
480 range.minlen = max(range.minlen, minlen);
481 ret = btrfs_trim_fs(fs_info, &range);
482 if (ret < 0)
483 return ret;
484
485 if (copy_to_user(arg, &range, sizeof(range)))
486 return -EFAULT;
487
488 return 0;
489 }
490
491 int __pure btrfs_is_empty_uuid(u8 *uuid)
492 {
493 int i;
494
495 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
496 if (uuid[i])
497 return 0;
498 }
499 return 1;
500 }
501
502 static noinline int create_subvol(struct user_namespace *mnt_userns,
503 struct inode *dir, struct dentry *dentry,
504 const char *name, int namelen,
505 struct btrfs_qgroup_inherit *inherit)
506 {
507 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
508 struct btrfs_trans_handle *trans;
509 struct btrfs_key key;
510 struct btrfs_root_item *root_item;
511 struct btrfs_inode_item *inode_item;
512 struct extent_buffer *leaf;
513 struct btrfs_root *root = BTRFS_I(dir)->root;
514 struct btrfs_root *new_root;
515 struct btrfs_block_rsv block_rsv;
516 struct timespec64 cur_time = current_time(dir);
517 struct inode *inode;
518 int ret;
519 int err;
520 dev_t anon_dev = 0;
521 u64 objectid;
522 u64 index = 0;
523
524 root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
525 if (!root_item)
526 return -ENOMEM;
527
528 ret = btrfs_get_free_objectid(fs_info->tree_root, &objectid);
529 if (ret)
530 goto fail_free;
531
532 ret = get_anon_bdev(&anon_dev);
533 if (ret < 0)
534 goto fail_free;
535
536 /*
537 * Don't create subvolume whose level is not zero. Or qgroup will be
538 * screwed up since it assumes subvolume qgroup's level to be 0.
539 */
540 if (btrfs_qgroup_level(objectid)) {
541 ret = -ENOSPC;
542 goto fail_free;
543 }
544
545 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
546 /*
547 * The same as the snapshot creation, please see the comment
548 * of create_snapshot().
549 */
550 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 8, false);
551 if (ret)
552 goto fail_free;
553
554 trans = btrfs_start_transaction(root, 0);
555 if (IS_ERR(trans)) {
556 ret = PTR_ERR(trans);
557 btrfs_subvolume_release_metadata(root, &block_rsv);
558 goto fail_free;
559 }
560 trans->block_rsv = &block_rsv;
561 trans->bytes_reserved = block_rsv.size;
562
563 ret = btrfs_qgroup_inherit(trans, 0, objectid, inherit);
564 if (ret)
565 goto fail;
566
567 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0,
568 BTRFS_NESTING_NORMAL);
569 if (IS_ERR(leaf)) {
570 ret = PTR_ERR(leaf);
571 goto fail;
572 }
573
574 btrfs_mark_buffer_dirty(leaf);
575
576 inode_item = &root_item->inode;
577 btrfs_set_stack_inode_generation(inode_item, 1);
578 btrfs_set_stack_inode_size(inode_item, 3);
579 btrfs_set_stack_inode_nlink(inode_item, 1);
580 btrfs_set_stack_inode_nbytes(inode_item,
581 fs_info->nodesize);
582 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
583
584 btrfs_set_root_flags(root_item, 0);
585 btrfs_set_root_limit(root_item, 0);
586 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
587
588 btrfs_set_root_bytenr(root_item, leaf->start);
589 btrfs_set_root_generation(root_item, trans->transid);
590 btrfs_set_root_level(root_item, 0);
591 btrfs_set_root_refs(root_item, 1);
592 btrfs_set_root_used(root_item, leaf->len);
593 btrfs_set_root_last_snapshot(root_item, 0);
594
595 btrfs_set_root_generation_v2(root_item,
596 btrfs_root_generation(root_item));
597 generate_random_guid(root_item->uuid);
598 btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);
599 btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);
600 root_item->ctime = root_item->otime;
601 btrfs_set_root_ctransid(root_item, trans->transid);
602 btrfs_set_root_otransid(root_item, trans->transid);
603
604 btrfs_tree_unlock(leaf);
605
606 btrfs_set_root_dirid(root_item, BTRFS_FIRST_FREE_OBJECTID);
607
608 key.objectid = objectid;
609 key.offset = 0;
610 key.type = BTRFS_ROOT_ITEM_KEY;
611 ret = btrfs_insert_root(trans, fs_info->tree_root, &key,
612 root_item);
613 if (ret) {
614 /*
615 * Since we don't abort the transaction in this case, free the
616 * tree block so that we don't leak space and leave the
617 * filesystem in an inconsistent state (an extent item in the
618 * extent tree without backreferences). Also no need to have
619 * the tree block locked since it is not in any tree at this
620 * point, so no other task can find it and use it.
621 */
622 btrfs_free_tree_block(trans, root, leaf, 0, 1);
623 free_extent_buffer(leaf);
624 goto fail;
625 }
626
627 free_extent_buffer(leaf);
628 leaf = NULL;
629
630 key.offset = (u64)-1;
631 new_root = btrfs_get_new_fs_root(fs_info, objectid, anon_dev);
632 if (IS_ERR(new_root)) {
633 free_anon_bdev(anon_dev);
634 ret = PTR_ERR(new_root);
635 btrfs_abort_transaction(trans, ret);
636 goto fail;
637 }
638 /* Freeing will be done in btrfs_put_root() of new_root */
639 anon_dev = 0;
640
641 ret = btrfs_record_root_in_trans(trans, new_root);
642 if (ret) {
643 btrfs_put_root(new_root);
644 btrfs_abort_transaction(trans, ret);
645 goto fail;
646 }
647
648 ret = btrfs_create_subvol_root(trans, new_root, root, mnt_userns);
649 btrfs_put_root(new_root);
650 if (ret) {
651 /* We potentially lose an unused inode item here */
652 btrfs_abort_transaction(trans, ret);
653 goto fail;
654 }
655
656 /*
657 * insert the directory item
658 */
659 ret = btrfs_set_inode_index(BTRFS_I(dir), &index);
660 if (ret) {
661 btrfs_abort_transaction(trans, ret);
662 goto fail;
663 }
664
665 ret = btrfs_insert_dir_item(trans, name, namelen, BTRFS_I(dir), &key,
666 BTRFS_FT_DIR, index);
667 if (ret) {
668 btrfs_abort_transaction(trans, ret);
669 goto fail;
670 }
671
672 btrfs_i_size_write(BTRFS_I(dir), dir->i_size + namelen * 2);
673 ret = btrfs_update_inode(trans, root, BTRFS_I(dir));
674 if (ret) {
675 btrfs_abort_transaction(trans, ret);
676 goto fail;
677 }
678
679 ret = btrfs_add_root_ref(trans, objectid, root->root_key.objectid,
680 btrfs_ino(BTRFS_I(dir)), index, name, namelen);
681 if (ret) {
682 btrfs_abort_transaction(trans, ret);
683 goto fail;
684 }
685
686 ret = btrfs_uuid_tree_add(trans, root_item->uuid,
687 BTRFS_UUID_KEY_SUBVOL, objectid);
688 if (ret)
689 btrfs_abort_transaction(trans, ret);
690
691 fail:
692 kfree(root_item);
693 trans->block_rsv = NULL;
694 trans->bytes_reserved = 0;
695 btrfs_subvolume_release_metadata(root, &block_rsv);
696
697 err = btrfs_commit_transaction(trans);
698 if (err && !ret)
699 ret = err;
700
701 if (!ret) {
702 inode = btrfs_lookup_dentry(dir, dentry);
703 if (IS_ERR(inode))
704 return PTR_ERR(inode);
705 d_instantiate(dentry, inode);
706 }
707 return ret;
708
709 fail_free:
710 if (anon_dev)
711 free_anon_bdev(anon_dev);
712 kfree(root_item);
713 return ret;
714 }
715
716 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
717 struct dentry *dentry, bool readonly,
718 struct btrfs_qgroup_inherit *inherit)
719 {
720 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
721 struct inode *inode;
722 struct btrfs_pending_snapshot *pending_snapshot;
723 struct btrfs_trans_handle *trans;
724 int ret;
725
726 if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
727 return -EINVAL;
728
729 if (atomic_read(&root->nr_swapfiles)) {
730 btrfs_warn(fs_info,
731 "cannot snapshot subvolume with active swapfile");
732 return -ETXTBSY;
733 }
734
735 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL);
736 if (!pending_snapshot)
737 return -ENOMEM;
738
739 ret = get_anon_bdev(&pending_snapshot->anon_dev);
740 if (ret < 0)
741 goto free_pending;
742 pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
743 GFP_KERNEL);
744 pending_snapshot->path = btrfs_alloc_path();
745 if (!pending_snapshot->root_item || !pending_snapshot->path) {
746 ret = -ENOMEM;
747 goto free_pending;
748 }
749
750 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
751 BTRFS_BLOCK_RSV_TEMP);
752 /*
753 * 1 - parent dir inode
754 * 2 - dir entries
755 * 1 - root item
756 * 2 - root ref/backref
757 * 1 - root of snapshot
758 * 1 - UUID item
759 */
760 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
761 &pending_snapshot->block_rsv, 8,
762 false);
763 if (ret)
764 goto free_pending;
765
766 pending_snapshot->dentry = dentry;
767 pending_snapshot->root = root;
768 pending_snapshot->readonly = readonly;
769 pending_snapshot->dir = dir;
770 pending_snapshot->inherit = inherit;
771
772 trans = btrfs_start_transaction(root, 0);
773 if (IS_ERR(trans)) {
774 ret = PTR_ERR(trans);
775 goto fail;
776 }
777
778 trans->pending_snapshot = pending_snapshot;
779
780 ret = btrfs_commit_transaction(trans);
781 if (ret)
782 goto fail;
783
784 ret = pending_snapshot->error;
785 if (ret)
786 goto fail;
787
788 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
789 if (ret)
790 goto fail;
791
792 inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
793 if (IS_ERR(inode)) {
794 ret = PTR_ERR(inode);
795 goto fail;
796 }
797
798 d_instantiate(dentry, inode);
799 ret = 0;
800 pending_snapshot->anon_dev = 0;
801 fail:
802 /* Prevent double freeing of anon_dev */
803 if (ret && pending_snapshot->snap)
804 pending_snapshot->snap->anon_dev = 0;
805 btrfs_put_root(pending_snapshot->snap);
806 btrfs_subvolume_release_metadata(root, &pending_snapshot->block_rsv);
807 free_pending:
808 if (pending_snapshot->anon_dev)
809 free_anon_bdev(pending_snapshot->anon_dev);
810 kfree(pending_snapshot->root_item);
811 btrfs_free_path(pending_snapshot->path);
812 kfree(pending_snapshot);
813
814 return ret;
815 }
816
817 /* copy of may_delete in fs/namei.c()
818 * Check whether we can remove a link victim from directory dir, check
819 * whether the type of victim is right.
820 * 1. We can't do it if dir is read-only (done in permission())
821 * 2. We should have write and exec permissions on dir
822 * 3. We can't remove anything from append-only dir
823 * 4. We can't do anything with immutable dir (done in permission())
824 * 5. If the sticky bit on dir is set we should either
825 * a. be owner of dir, or
826 * b. be owner of victim, or
827 * c. have CAP_FOWNER capability
828 * 6. If the victim is append-only or immutable we can't do anything with
829 * links pointing to it.
830 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
831 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
832 * 9. We can't remove a root or mountpoint.
833 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
834 * nfs_async_unlink().
835 */
836
837 static int btrfs_may_delete(struct user_namespace *mnt_userns,
838 struct inode *dir, struct dentry *victim, int isdir)
839 {
840 int error;
841
842 if (d_really_is_negative(victim))
843 return -ENOENT;
844
845 BUG_ON(d_inode(victim->d_parent) != dir);
846 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
847
848 error = inode_permission(mnt_userns, dir, MAY_WRITE | MAY_EXEC);
849 if (error)
850 return error;
851 if (IS_APPEND(dir))
852 return -EPERM;
853 if (check_sticky(mnt_userns, dir, d_inode(victim)) ||
854 IS_APPEND(d_inode(victim)) || IS_IMMUTABLE(d_inode(victim)) ||
855 IS_SWAPFILE(d_inode(victim)))
856 return -EPERM;
857 if (isdir) {
858 if (!d_is_dir(victim))
859 return -ENOTDIR;
860 if (IS_ROOT(victim))
861 return -EBUSY;
862 } else if (d_is_dir(victim))
863 return -EISDIR;
864 if (IS_DEADDIR(dir))
865 return -ENOENT;
866 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
867 return -EBUSY;
868 return 0;
869 }
870
871 /* copy of may_create in fs/namei.c() */
872 static inline int btrfs_may_create(struct user_namespace *mnt_userns,
873 struct inode *dir, struct dentry *child)
874 {
875 if (d_really_is_positive(child))
876 return -EEXIST;
877 if (IS_DEADDIR(dir))
878 return -ENOENT;
879 if (!fsuidgid_has_mapping(dir->i_sb, mnt_userns))
880 return -EOVERFLOW;
881 return inode_permission(mnt_userns, dir, MAY_WRITE | MAY_EXEC);
882 }
883
884 /*
885 * Create a new subvolume below @parent. This is largely modeled after
886 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
887 * inside this filesystem so it's quite a bit simpler.
888 */
889 static noinline int btrfs_mksubvol(const struct path *parent,
890 struct user_namespace *mnt_userns,
891 const char *name, int namelen,
892 struct btrfs_root *snap_src,
893 bool readonly,
894 struct btrfs_qgroup_inherit *inherit)
895 {
896 struct inode *dir = d_inode(parent->dentry);
897 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
898 struct dentry *dentry;
899 int error;
900
901 error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
902 if (error == -EINTR)
903 return error;
904
905 dentry = lookup_one(mnt_userns, name, parent->dentry, namelen);
906 error = PTR_ERR(dentry);
907 if (IS_ERR(dentry))
908 goto out_unlock;
909
910 error = btrfs_may_create(mnt_userns, dir, dentry);
911 if (error)
912 goto out_dput;
913
914 /*
915 * even if this name doesn't exist, we may get hash collisions.
916 * check for them now when we can safely fail
917 */
918 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
919 dir->i_ino, name,
920 namelen);
921 if (error)
922 goto out_dput;
923
924 down_read(&fs_info->subvol_sem);
925
926 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
927 goto out_up_read;
928
929 if (snap_src)
930 error = create_snapshot(snap_src, dir, dentry, readonly, inherit);
931 else
932 error = create_subvol(mnt_userns, dir, dentry, name, namelen, inherit);
933
934 if (!error)
935 fsnotify_mkdir(dir, dentry);
936 out_up_read:
937 up_read(&fs_info->subvol_sem);
938 out_dput:
939 dput(dentry);
940 out_unlock:
941 btrfs_inode_unlock(dir, 0);
942 return error;
943 }
944
945 static noinline int btrfs_mksnapshot(const struct path *parent,
946 struct user_namespace *mnt_userns,
947 const char *name, int namelen,
948 struct btrfs_root *root,
949 bool readonly,
950 struct btrfs_qgroup_inherit *inherit)
951 {
952 int ret;
953 bool snapshot_force_cow = false;
954
955 /*
956 * Force new buffered writes to reserve space even when NOCOW is
957 * possible. This is to avoid later writeback (running dealloc) to
958 * fallback to COW mode and unexpectedly fail with ENOSPC.
959 */
960 btrfs_drew_read_lock(&root->snapshot_lock);
961
962 ret = btrfs_start_delalloc_snapshot(root, false);
963 if (ret)
964 goto out;
965
966 /*
967 * All previous writes have started writeback in NOCOW mode, so now
968 * we force future writes to fallback to COW mode during snapshot
969 * creation.
970 */
971 atomic_inc(&root->snapshot_force_cow);
972 snapshot_force_cow = true;
973
974 btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
975
976 ret = btrfs_mksubvol(parent, mnt_userns, name, namelen,
977 root, readonly, inherit);
978 out:
979 if (snapshot_force_cow)
980 atomic_dec(&root->snapshot_force_cow);
981 btrfs_drew_read_unlock(&root->snapshot_lock);
982 return ret;
983 }
984
985 /*
986 * When we're defragging a range, we don't want to kick it off again
987 * if it is really just waiting for delalloc to send it down.
988 * If we find a nice big extent or delalloc range for the bytes in the
989 * file you want to defrag, we return 0 to let you know to skip this
990 * part of the file
991 */
992 static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
993 {
994 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
995 struct extent_map *em = NULL;
996 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
997 u64 end;
998
999 read_lock(&em_tree->lock);
1000 em = lookup_extent_mapping(em_tree, offset, PAGE_SIZE);
1001 read_unlock(&em_tree->lock);
1002
1003 if (em) {
1004 end = extent_map_end(em);
1005 free_extent_map(em);
1006 if (end - offset > thresh)
1007 return 0;
1008 }
1009 /* if we already have a nice delalloc here, just stop */
1010 thresh /= 2;
1011 end = count_range_bits(io_tree, &offset, offset + thresh,
1012 thresh, EXTENT_DELALLOC, 1);
1013 if (end >= thresh)
1014 return 0;
1015 return 1;
1016 }
1017
1018 /*
1019 * helper function to walk through a file and find extents
1020 * newer than a specific transid, and smaller than thresh.
1021 *
1022 * This is used by the defragging code to find new and small
1023 * extents
1024 */
1025 static int find_new_extents(struct btrfs_root *root,
1026 struct inode *inode, u64 newer_than,
1027 u64 *off, u32 thresh)
1028 {
1029 struct btrfs_path *path;
1030 struct btrfs_key min_key;
1031 struct extent_buffer *leaf;
1032 struct btrfs_file_extent_item *extent;
1033 int type;
1034 int ret;
1035 u64 ino = btrfs_ino(BTRFS_I(inode));
1036
1037 path = btrfs_alloc_path();
1038 if (!path)
1039 return -ENOMEM;
1040
1041 min_key.objectid = ino;
1042 min_key.type = BTRFS_EXTENT_DATA_KEY;
1043 min_key.offset = *off;
1044
1045 while (1) {
1046 ret = btrfs_search_forward(root, &min_key, path, newer_than);
1047 if (ret != 0)
1048 goto none;
1049 process_slot:
1050 if (min_key.objectid != ino)
1051 goto none;
1052 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
1053 goto none;
1054
1055 leaf = path->nodes[0];
1056 extent = btrfs_item_ptr(leaf, path->slots[0],
1057 struct btrfs_file_extent_item);
1058
1059 type = btrfs_file_extent_type(leaf, extent);
1060 if (type == BTRFS_FILE_EXTENT_REG &&
1061 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
1062 check_defrag_in_cache(inode, min_key.offset, thresh)) {
1063 *off = min_key.offset;
1064 btrfs_free_path(path);
1065 return 0;
1066 }
1067
1068 path->slots[0]++;
1069 if (path->slots[0] < btrfs_header_nritems(leaf)) {
1070 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
1071 goto process_slot;
1072 }
1073
1074 if (min_key.offset == (u64)-1)
1075 goto none;
1076
1077 min_key.offset++;
1078 btrfs_release_path(path);
1079 }
1080 none:
1081 btrfs_free_path(path);
1082 return -ENOENT;
1083 }
1084
1085 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
1086 {
1087 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1088 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1089 struct extent_map *em;
1090 u64 len = PAGE_SIZE;
1091
1092 /*
1093 * hopefully we have this extent in the tree already, try without
1094 * the full extent lock
1095 */
1096 read_lock(&em_tree->lock);
1097 em = lookup_extent_mapping(em_tree, start, len);
1098 read_unlock(&em_tree->lock);
1099
1100 if (!em) {
1101 struct extent_state *cached = NULL;
1102 u64 end = start + len - 1;
1103
1104 /* get the big lock and read metadata off disk */
1105 lock_extent_bits(io_tree, start, end, &cached);
1106 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len);
1107 unlock_extent_cached(io_tree, start, end, &cached);
1108
1109 if (IS_ERR(em))
1110 return NULL;
1111 }
1112
1113 return em;
1114 }
1115
1116 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1117 {
1118 struct extent_map *next;
1119 bool ret = true;
1120
1121 /* this is the last extent */
1122 if (em->start + em->len >= i_size_read(inode))
1123 return false;
1124
1125 next = defrag_lookup_extent(inode, em->start + em->len);
1126 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1127 ret = false;
1128 else if ((em->block_start + em->block_len == next->block_start) &&
1129 (em->block_len > SZ_128K && next->block_len > SZ_128K))
1130 ret = false;
1131
1132 free_extent_map(next);
1133 return ret;
1134 }
1135
1136 static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1137 u64 *last_len, u64 *skip, u64 *defrag_end,
1138 int compress)
1139 {
1140 struct extent_map *em;
1141 int ret = 1;
1142 bool next_mergeable = true;
1143 bool prev_mergeable = true;
1144
1145 /*
1146 * make sure that once we start defragging an extent, we keep on
1147 * defragging it
1148 */
1149 if (start < *defrag_end)
1150 return 1;
1151
1152 *skip = 0;
1153
1154 em = defrag_lookup_extent(inode, start);
1155 if (!em)
1156 return 0;
1157
1158 /* this will cover holes, and inline extents */
1159 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1160 ret = 0;
1161 goto out;
1162 }
1163
1164 if (!*defrag_end)
1165 prev_mergeable = false;
1166
1167 next_mergeable = defrag_check_next_extent(inode, em);
1168 /*
1169 * we hit a real extent, if it is big or the next extent is not a
1170 * real extent, don't bother defragging it
1171 */
1172 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1173 (em->len >= thresh || (!next_mergeable && !prev_mergeable)))
1174 ret = 0;
1175 out:
1176 /*
1177 * last_len ends up being a counter of how many bytes we've defragged.
1178 * every time we choose not to defrag an extent, we reset *last_len
1179 * so that the next tiny extent will force a defrag.
1180 *
1181 * The end result of this is that tiny extents before a single big
1182 * extent will force at least part of that big extent to be defragged.
1183 */
1184 if (ret) {
1185 *defrag_end = extent_map_end(em);
1186 } else {
1187 *last_len = 0;
1188 *skip = extent_map_end(em);
1189 *defrag_end = 0;
1190 }
1191
1192 free_extent_map(em);
1193 return ret;
1194 }
1195
1196 /*
1197 * it doesn't do much good to defrag one or two pages
1198 * at a time. This pulls in a nice chunk of pages
1199 * to COW and defrag.
1200 *
1201 * It also makes sure the delalloc code has enough
1202 * dirty data to avoid making new small extents as part
1203 * of the defrag
1204 *
1205 * It's a good idea to start RA on this range
1206 * before calling this.
1207 */
1208 static int cluster_pages_for_defrag(struct inode *inode,
1209 struct page **pages,
1210 unsigned long start_index,
1211 unsigned long num_pages)
1212 {
1213 unsigned long file_end;
1214 u64 isize = i_size_read(inode);
1215 u64 page_start;
1216 u64 page_end;
1217 u64 page_cnt;
1218 u64 start = (u64)start_index << PAGE_SHIFT;
1219 u64 search_start;
1220 int ret;
1221 int i;
1222 int i_done;
1223 struct btrfs_ordered_extent *ordered;
1224 struct extent_state *cached_state = NULL;
1225 struct extent_io_tree *tree;
1226 struct extent_changeset *data_reserved = NULL;
1227 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1228
1229 file_end = (isize - 1) >> PAGE_SHIFT;
1230 if (!isize || start_index > file_end)
1231 return 0;
1232
1233 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1234
1235 ret = btrfs_delalloc_reserve_space(BTRFS_I(inode), &data_reserved,
1236 start, page_cnt << PAGE_SHIFT);
1237 if (ret)
1238 return ret;
1239 i_done = 0;
1240 tree = &BTRFS_I(inode)->io_tree;
1241
1242 /* step one, lock all the pages */
1243 for (i = 0; i < page_cnt; i++) {
1244 struct page *page;
1245 again:
1246 page = find_or_create_page(inode->i_mapping,
1247 start_index + i, mask);
1248 if (!page)
1249 break;
1250
1251 ret = set_page_extent_mapped(page);
1252 if (ret < 0) {
1253 unlock_page(page);
1254 put_page(page);
1255 break;
1256 }
1257
1258 page_start = page_offset(page);
1259 page_end = page_start + PAGE_SIZE - 1;
1260 while (1) {
1261 lock_extent_bits(tree, page_start, page_end,
1262 &cached_state);
1263 ordered = btrfs_lookup_ordered_extent(BTRFS_I(inode),
1264 page_start);
1265 unlock_extent_cached(tree, page_start, page_end,
1266 &cached_state);
1267 if (!ordered)
1268 break;
1269
1270 unlock_page(page);
1271 btrfs_start_ordered_extent(ordered, 1);
1272 btrfs_put_ordered_extent(ordered);
1273 lock_page(page);
1274 /*
1275 * we unlocked the page above, so we need check if
1276 * it was released or not.
1277 */
1278 if (page->mapping != inode->i_mapping) {
1279 unlock_page(page);
1280 put_page(page);
1281 goto again;
1282 }
1283 }
1284
1285 if (!PageUptodate(page)) {
1286 btrfs_readpage(NULL, page);
1287 lock_page(page);
1288 if (!PageUptodate(page)) {
1289 unlock_page(page);
1290 put_page(page);
1291 ret = -EIO;
1292 break;
1293 }
1294 }
1295
1296 if (page->mapping != inode->i_mapping) {
1297 unlock_page(page);
1298 put_page(page);
1299 goto again;
1300 }
1301
1302 pages[i] = page;
1303 i_done++;
1304 }
1305 if (!i_done || ret)
1306 goto out;
1307
1308 if (!(inode->i_sb->s_flags & SB_ACTIVE))
1309 goto out;
1310
1311 /*
1312 * so now we have a nice long stream of locked
1313 * and up to date pages, lets wait on them
1314 */
1315 for (i = 0; i < i_done; i++)
1316 wait_on_page_writeback(pages[i]);
1317
1318 page_start = page_offset(pages[0]);
1319 page_end = page_offset(pages[i_done - 1]) + PAGE_SIZE;
1320
1321 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1322 page_start, page_end - 1, &cached_state);
1323
1324 /*
1325 * When defragmenting we skip ranges that have holes or inline extents,
1326 * (check should_defrag_range()), to avoid unnecessary IO and wasting
1327 * space. At btrfs_defrag_file(), we check if a range should be defragged
1328 * before locking the inode and then, if it should, we trigger a sync
1329 * page cache readahead - we lock the inode only after that to avoid
1330 * blocking for too long other tasks that possibly want to operate on
1331 * other file ranges. But before we were able to get the inode lock,
1332 * some other task may have punched a hole in the range, or we may have
1333 * now an inline extent, in which case we should not defrag. So check
1334 * for that here, where we have the inode and the range locked, and bail
1335 * out if that happened.
1336 */
1337 search_start = page_start;
1338 while (search_start < page_end) {
1339 struct extent_map *em;
1340
1341 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, search_start,
1342 page_end - search_start);
1343 if (IS_ERR(em)) {
1344 ret = PTR_ERR(em);
1345 goto out_unlock_range;
1346 }
1347 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1348 free_extent_map(em);
1349 /* Ok, 0 means we did not defrag anything */
1350 ret = 0;
1351 goto out_unlock_range;
1352 }
1353 search_start = extent_map_end(em);
1354 free_extent_map(em);
1355 }
1356
1357 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1358 page_end - 1, EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |
1359 EXTENT_DEFRAG, 0, 0, &cached_state);
1360
1361 if (i_done != page_cnt) {
1362 spin_lock(&BTRFS_I(inode)->lock);
1363 btrfs_mod_outstanding_extents(BTRFS_I(inode), 1);
1364 spin_unlock(&BTRFS_I(inode)->lock);
1365 btrfs_delalloc_release_space(BTRFS_I(inode), data_reserved,
1366 start, (page_cnt - i_done) << PAGE_SHIFT, true);
1367 }
1368
1369
1370 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1371 &cached_state);
1372
1373 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1374 page_start, page_end - 1, &cached_state);
1375
1376 for (i = 0; i < i_done; i++) {
1377 clear_page_dirty_for_io(pages[i]);
1378 ClearPageChecked(pages[i]);
1379 set_page_dirty(pages[i]);
1380 unlock_page(pages[i]);
1381 put_page(pages[i]);
1382 }
1383 btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT);
1384 extent_changeset_free(data_reserved);
1385 return i_done;
1386
1387 out_unlock_range:
1388 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1389 page_start, page_end - 1, &cached_state);
1390 out:
1391 for (i = 0; i < i_done; i++) {
1392 unlock_page(pages[i]);
1393 put_page(pages[i]);
1394 }
1395 btrfs_delalloc_release_space(BTRFS_I(inode), data_reserved,
1396 start, page_cnt << PAGE_SHIFT, true);
1397 btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT);
1398 extent_changeset_free(data_reserved);
1399 return ret;
1400
1401 }
1402
1403 int btrfs_defrag_file(struct inode *inode, struct file *file,
1404 struct btrfs_ioctl_defrag_range_args *range,
1405 u64 newer_than, unsigned long max_to_defrag)
1406 {
1407 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1408 struct btrfs_root *root = BTRFS_I(inode)->root;
1409 struct file_ra_state *ra = NULL;
1410 unsigned long last_index;
1411 u64 isize = i_size_read(inode);
1412 u64 last_len = 0;
1413 u64 skip = 0;
1414 u64 defrag_end = 0;
1415 u64 newer_off = range->start;
1416 unsigned long i;
1417 unsigned long ra_index = 0;
1418 int ret;
1419 int defrag_count = 0;
1420 int compress_type = BTRFS_COMPRESS_ZLIB;
1421 u32 extent_thresh = range->extent_thresh;
1422 unsigned long max_cluster = SZ_256K >> PAGE_SHIFT;
1423 unsigned long cluster = max_cluster;
1424 u64 new_align = ~((u64)SZ_128K - 1);
1425 struct page **pages = NULL;
1426 bool do_compress = range->flags & BTRFS_DEFRAG_RANGE_COMPRESS;
1427
1428 if (isize == 0)
1429 return 0;
1430
1431 if (range->start >= isize)
1432 return -EINVAL;
1433
1434 if (do_compress) {
1435 if (range->compress_type >= BTRFS_NR_COMPRESS_TYPES)
1436 return -EINVAL;
1437 if (range->compress_type)
1438 compress_type = range->compress_type;
1439 }
1440
1441 if (extent_thresh == 0)
1442 extent_thresh = SZ_256K;
1443
1444 /*
1445 * If we were not given a file, allocate a readahead context. As
1446 * readahead is just an optimization, defrag will work without it so
1447 * we don't error out.
1448 */
1449 if (!file) {
1450 ra = kzalloc(sizeof(*ra), GFP_KERNEL);
1451 if (ra)
1452 file_ra_state_init(ra, inode->i_mapping);
1453 } else {
1454 ra = &file->f_ra;
1455 }
1456
1457 pages = kmalloc_array(max_cluster, sizeof(struct page *), GFP_KERNEL);
1458 if (!pages) {
1459 ret = -ENOMEM;
1460 goto out_ra;
1461 }
1462
1463 /* find the last page to defrag */
1464 if (range->start + range->len > range->start) {
1465 last_index = min_t(u64, isize - 1,
1466 range->start + range->len - 1) >> PAGE_SHIFT;
1467 } else {
1468 last_index = (isize - 1) >> PAGE_SHIFT;
1469 }
1470
1471 if (newer_than) {
1472 ret = find_new_extents(root, inode, newer_than,
1473 &newer_off, SZ_64K);
1474 if (!ret) {
1475 range->start = newer_off;
1476 /*
1477 * we always align our defrag to help keep
1478 * the extents in the file evenly spaced
1479 */
1480 i = (newer_off & new_align) >> PAGE_SHIFT;
1481 } else
1482 goto out_ra;
1483 } else {
1484 i = range->start >> PAGE_SHIFT;
1485 }
1486 if (!max_to_defrag)
1487 max_to_defrag = last_index - i + 1;
1488
1489 /*
1490 * make writeback starts from i, so the defrag range can be
1491 * written sequentially.
1492 */
1493 if (i < inode->i_mapping->writeback_index)
1494 inode->i_mapping->writeback_index = i;
1495
1496 while (i <= last_index && defrag_count < max_to_defrag &&
1497 (i < DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE))) {
1498 /*
1499 * make sure we stop running if someone unmounts
1500 * the FS
1501 */
1502 if (!(inode->i_sb->s_flags & SB_ACTIVE))
1503 break;
1504
1505 if (btrfs_defrag_cancelled(fs_info)) {
1506 btrfs_debug(fs_info, "defrag_file cancelled");
1507 ret = -EAGAIN;
1508 goto error;
1509 }
1510
1511 if (!should_defrag_range(inode, (u64)i << PAGE_SHIFT,
1512 extent_thresh, &last_len, &skip,
1513 &defrag_end, do_compress)){
1514 unsigned long next;
1515 /*
1516 * the should_defrag function tells us how much to skip
1517 * bump our counter by the suggested amount
1518 */
1519 next = DIV_ROUND_UP(skip, PAGE_SIZE);
1520 i = max(i + 1, next);
1521 continue;
1522 }
1523
1524 if (!newer_than) {
1525 cluster = (PAGE_ALIGN(defrag_end) >>
1526 PAGE_SHIFT) - i;
1527 cluster = min(cluster, max_cluster);
1528 } else {
1529 cluster = max_cluster;
1530 }
1531
1532 if (i + cluster > ra_index) {
1533 ra_index = max(i, ra_index);
1534 if (ra)
1535 page_cache_sync_readahead(inode->i_mapping, ra,
1536 file, ra_index, cluster);
1537 ra_index += cluster;
1538 }
1539
1540 btrfs_inode_lock(inode, 0);
1541 if (IS_SWAPFILE(inode)) {
1542 ret = -ETXTBSY;
1543 } else {
1544 if (do_compress)
1545 BTRFS_I(inode)->defrag_compress = compress_type;
1546 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1547 }
1548 if (ret < 0) {
1549 btrfs_inode_unlock(inode, 0);
1550 goto out_ra;
1551 }
1552
1553 defrag_count += ret;
1554 balance_dirty_pages_ratelimited(inode->i_mapping);
1555 btrfs_inode_unlock(inode, 0);
1556
1557 if (newer_than) {
1558 if (newer_off == (u64)-1)
1559 break;
1560
1561 if (ret > 0)
1562 i += ret;
1563
1564 newer_off = max(newer_off + 1,
1565 (u64)i << PAGE_SHIFT);
1566
1567 ret = find_new_extents(root, inode, newer_than,
1568 &newer_off, SZ_64K);
1569 if (!ret) {
1570 range->start = newer_off;
1571 i = (newer_off & new_align) >> PAGE_SHIFT;
1572 } else {
1573 break;
1574 }
1575 } else {
1576 if (ret > 0) {
1577 i += ret;
1578 last_len += ret << PAGE_SHIFT;
1579 } else {
1580 i++;
1581 last_len = 0;
1582 }
1583 }
1584 }
1585
1586 ret = defrag_count;
1587 error:
1588 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1589 filemap_flush(inode->i_mapping);
1590 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1591 &BTRFS_I(inode)->runtime_flags))
1592 filemap_flush(inode->i_mapping);
1593 }
1594
1595 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1596 btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
1597 } else if (range->compress_type == BTRFS_COMPRESS_ZSTD) {
1598 btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
1599 }
1600
1601 out_ra:
1602 if (do_compress) {
1603 btrfs_inode_lock(inode, 0);
1604 BTRFS_I(inode)->defrag_compress = BTRFS_COMPRESS_NONE;
1605 btrfs_inode_unlock(inode, 0);
1606 }
1607 if (!file)
1608 kfree(ra);
1609 kfree(pages);
1610 return ret;
1611 }
1612
1613 /*
1614 * Try to start exclusive operation @type or cancel it if it's running.
1615 *
1616 * Return:
1617 * 0 - normal mode, newly claimed op started
1618 * >0 - normal mode, something else is running,
1619 * return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS to user space
1620 * ECANCELED - cancel mode, successful cancel
1621 * ENOTCONN - cancel mode, operation not running anymore
1622 */
1623 static int exclop_start_or_cancel_reloc(struct btrfs_fs_info *fs_info,
1624 enum btrfs_exclusive_operation type, bool cancel)
1625 {
1626 if (!cancel) {
1627 /* Start normal op */
1628 if (!btrfs_exclop_start(fs_info, type))
1629 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1630 /* Exclusive operation is now claimed */
1631 return 0;
1632 }
1633
1634 /* Cancel running op */
1635 if (btrfs_exclop_start_try_lock(fs_info, type)) {
1636 /*
1637 * This blocks any exclop finish from setting it to NONE, so we
1638 * request cancellation. Either it runs and we will wait for it,
1639 * or it has finished and no waiting will happen.
1640 */
1641 atomic_inc(&fs_info->reloc_cancel_req);
1642 btrfs_exclop_start_unlock(fs_info);
1643
1644 if (test_bit(BTRFS_FS_RELOC_RUNNING, &fs_info->flags))
1645 wait_on_bit(&fs_info->flags, BTRFS_FS_RELOC_RUNNING,
1646 TASK_INTERRUPTIBLE);
1647
1648 return -ECANCELED;
1649 }
1650
1651 /* Something else is running or none */
1652 return -ENOTCONN;
1653 }
1654
1655 static noinline int btrfs_ioctl_resize(struct file *file,
1656 void __user *arg)
1657 {
1658 struct inode *inode = file_inode(file);
1659 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1660 u64 new_size;
1661 u64 old_size;
1662 u64 devid = 1;
1663 struct btrfs_root *root = BTRFS_I(inode)->root;
1664 struct btrfs_ioctl_vol_args *vol_args;
1665 struct btrfs_trans_handle *trans;
1666 struct btrfs_device *device = NULL;
1667 char *sizestr;
1668 char *retptr;
1669 char *devstr = NULL;
1670 int ret = 0;
1671 int mod = 0;
1672 bool cancel;
1673
1674 if (!capable(CAP_SYS_ADMIN))
1675 return -EPERM;
1676
1677 ret = mnt_want_write_file(file);
1678 if (ret)
1679 return ret;
1680
1681 /*
1682 * Read the arguments before checking exclusivity to be able to
1683 * distinguish regular resize and cancel
1684 */
1685 vol_args = memdup_user(arg, sizeof(*vol_args));
1686 if (IS_ERR(vol_args)) {
1687 ret = PTR_ERR(vol_args);
1688 goto out_drop;
1689 }
1690 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1691 sizestr = vol_args->name;
1692 cancel = (strcmp("cancel", sizestr) == 0);
1693 ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_RESIZE, cancel);
1694 if (ret)
1695 goto out_free;
1696 /* Exclusive operation is now claimed */
1697
1698 devstr = strchr(sizestr, ':');
1699 if (devstr) {
1700 sizestr = devstr + 1;
1701 *devstr = '\0';
1702 devstr = vol_args->name;
1703 ret = kstrtoull(devstr, 10, &devid);
1704 if (ret)
1705 goto out_finish;
1706 if (!devid) {
1707 ret = -EINVAL;
1708 goto out_finish;
1709 }
1710 btrfs_info(fs_info, "resizing devid %llu", devid);
1711 }
1712
1713 device = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL);
1714 if (!device) {
1715 btrfs_info(fs_info, "resizer unable to find device %llu",
1716 devid);
1717 ret = -ENODEV;
1718 goto out_finish;
1719 }
1720
1721 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
1722 btrfs_info(fs_info,
1723 "resizer unable to apply on readonly device %llu",
1724 devid);
1725 ret = -EPERM;
1726 goto out_finish;
1727 }
1728
1729 if (!strcmp(sizestr, "max"))
1730 new_size = device->bdev->bd_inode->i_size;
1731 else {
1732 if (sizestr[0] == '-') {
1733 mod = -1;
1734 sizestr++;
1735 } else if (sizestr[0] == '+') {
1736 mod = 1;
1737 sizestr++;
1738 }
1739 new_size = memparse(sizestr, &retptr);
1740 if (*retptr != '\0' || new_size == 0) {
1741 ret = -EINVAL;
1742 goto out_finish;
1743 }
1744 }
1745
1746 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
1747 ret = -EPERM;
1748 goto out_finish;
1749 }
1750
1751 old_size = btrfs_device_get_total_bytes(device);
1752
1753 if (mod < 0) {
1754 if (new_size > old_size) {
1755 ret = -EINVAL;
1756 goto out_finish;
1757 }
1758 new_size = old_size - new_size;
1759 } else if (mod > 0) {
1760 if (new_size > ULLONG_MAX - old_size) {
1761 ret = -ERANGE;
1762 goto out_finish;
1763 }
1764 new_size = old_size + new_size;
1765 }
1766
1767 if (new_size < SZ_256M) {
1768 ret = -EINVAL;
1769 goto out_finish;
1770 }
1771 if (new_size > device->bdev->bd_inode->i_size) {
1772 ret = -EFBIG;
1773 goto out_finish;
1774 }
1775
1776 new_size = round_down(new_size, fs_info->sectorsize);
1777
1778 if (new_size > old_size) {
1779 trans = btrfs_start_transaction(root, 0);
1780 if (IS_ERR(trans)) {
1781 ret = PTR_ERR(trans);
1782 goto out_finish;
1783 }
1784 ret = btrfs_grow_device(trans, device, new_size);
1785 btrfs_commit_transaction(trans);
1786 } else if (new_size < old_size) {
1787 ret = btrfs_shrink_device(device, new_size);
1788 } /* equal, nothing need to do */
1789
1790 if (ret == 0 && new_size != old_size)
1791 btrfs_info_in_rcu(fs_info,
1792 "resize device %s (devid %llu) from %llu to %llu",
1793 rcu_str_deref(device->name), device->devid,
1794 old_size, new_size);
1795 out_finish:
1796 btrfs_exclop_finish(fs_info);
1797 out_free:
1798 kfree(vol_args);
1799 out_drop:
1800 mnt_drop_write_file(file);
1801 return ret;
1802 }
1803
1804 static noinline int __btrfs_ioctl_snap_create(struct file *file,
1805 struct user_namespace *mnt_userns,
1806 const char *name, unsigned long fd, int subvol,
1807 bool readonly,
1808 struct btrfs_qgroup_inherit *inherit)
1809 {
1810 int namelen;
1811 int ret = 0;
1812
1813 if (!S_ISDIR(file_inode(file)->i_mode))
1814 return -ENOTDIR;
1815
1816 ret = mnt_want_write_file(file);
1817 if (ret)
1818 goto out;
1819
1820 namelen = strlen(name);
1821 if (strchr(name, '/')) {
1822 ret = -EINVAL;
1823 goto out_drop_write;
1824 }
1825
1826 if (name[0] == '.' &&
1827 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1828 ret = -EEXIST;
1829 goto out_drop_write;
1830 }
1831
1832 if (subvol) {
1833 ret = btrfs_mksubvol(&file->f_path, mnt_userns, name,
1834 namelen, NULL, readonly, inherit);
1835 } else {
1836 struct fd src = fdget(fd);
1837 struct inode *src_inode;
1838 if (!src.file) {
1839 ret = -EINVAL;
1840 goto out_drop_write;
1841 }
1842
1843 src_inode = file_inode(src.file);
1844 if (src_inode->i_sb != file_inode(file)->i_sb) {
1845 btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
1846 "Snapshot src from another FS");
1847 ret = -EXDEV;
1848 } else if (!inode_owner_or_capable(mnt_userns, src_inode)) {
1849 /*
1850 * Subvolume creation is not restricted, but snapshots
1851 * are limited to own subvolumes only
1852 */
1853 ret = -EPERM;
1854 } else {
1855 ret = btrfs_mksnapshot(&file->f_path, mnt_userns,
1856 name, namelen,
1857 BTRFS_I(src_inode)->root,
1858 readonly, inherit);
1859 }
1860 fdput(src);
1861 }
1862 out_drop_write:
1863 mnt_drop_write_file(file);
1864 out:
1865 return ret;
1866 }
1867
1868 static noinline int btrfs_ioctl_snap_create(struct file *file,
1869 void __user *arg, int subvol)
1870 {
1871 struct btrfs_ioctl_vol_args *vol_args;
1872 int ret;
1873
1874 if (!S_ISDIR(file_inode(file)->i_mode))
1875 return -ENOTDIR;
1876
1877 vol_args = memdup_user(arg, sizeof(*vol_args));
1878 if (IS_ERR(vol_args))
1879 return PTR_ERR(vol_args);
1880 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1881
1882 ret = __btrfs_ioctl_snap_create(file, file_mnt_user_ns(file),
1883 vol_args->name, vol_args->fd, subvol,
1884 false, NULL);
1885
1886 kfree(vol_args);
1887 return ret;
1888 }
1889
1890 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1891 void __user *arg, int subvol)
1892 {
1893 struct btrfs_ioctl_vol_args_v2 *vol_args;
1894 int ret;
1895 bool readonly = false;
1896 struct btrfs_qgroup_inherit *inherit = NULL;
1897
1898 if (!S_ISDIR(file_inode(file)->i_mode))
1899 return -ENOTDIR;
1900
1901 vol_args = memdup_user(arg, sizeof(*vol_args));
1902 if (IS_ERR(vol_args))
1903 return PTR_ERR(vol_args);
1904 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1905
1906 if (vol_args->flags & ~BTRFS_SUBVOL_CREATE_ARGS_MASK) {
1907 ret = -EOPNOTSUPP;
1908 goto free_args;
1909 }
1910
1911 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1912 readonly = true;
1913 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1914 u64 nums;
1915
1916 if (vol_args->size < sizeof(*inherit) ||
1917 vol_args->size > PAGE_SIZE) {
1918 ret = -EINVAL;
1919 goto free_args;
1920 }
1921 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1922 if (IS_ERR(inherit)) {
1923 ret = PTR_ERR(inherit);
1924 goto free_args;
1925 }
1926
1927 if (inherit->num_qgroups > PAGE_SIZE ||
1928 inherit->num_ref_copies > PAGE_SIZE ||
1929 inherit->num_excl_copies > PAGE_SIZE) {
1930 ret = -EINVAL;
1931 goto free_inherit;
1932 }
1933
1934 nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
1935 2 * inherit->num_excl_copies;
1936 if (vol_args->size != struct_size(inherit, qgroups, nums)) {
1937 ret = -EINVAL;
1938 goto free_inherit;
1939 }
1940 }
1941
1942 ret = __btrfs_ioctl_snap_create(file, file_mnt_user_ns(file),
1943 vol_args->name, vol_args->fd, subvol,
1944 readonly, inherit);
1945 if (ret)
1946 goto free_inherit;
1947 free_inherit:
1948 kfree(inherit);
1949 free_args:
1950 kfree(vol_args);
1951 return ret;
1952 }
1953
1954 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1955 void __user *arg)
1956 {
1957 struct inode *inode = file_inode(file);
1958 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1959 struct btrfs_root *root = BTRFS_I(inode)->root;
1960 int ret = 0;
1961 u64 flags = 0;
1962
1963 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)
1964 return -EINVAL;
1965
1966 down_read(&fs_info->subvol_sem);
1967 if (btrfs_root_readonly(root))
1968 flags |= BTRFS_SUBVOL_RDONLY;
1969 up_read(&fs_info->subvol_sem);
1970
1971 if (copy_to_user(arg, &flags, sizeof(flags)))
1972 ret = -EFAULT;
1973
1974 return ret;
1975 }
1976
1977 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1978 void __user *arg)
1979 {
1980 struct inode *inode = file_inode(file);
1981 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1982 struct btrfs_root *root = BTRFS_I(inode)->root;
1983 struct btrfs_trans_handle *trans;
1984 u64 root_flags;
1985 u64 flags;
1986 int ret = 0;
1987
1988 if (!inode_owner_or_capable(file_mnt_user_ns(file), inode))
1989 return -EPERM;
1990
1991 ret = mnt_want_write_file(file);
1992 if (ret)
1993 goto out;
1994
1995 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
1996 ret = -EINVAL;
1997 goto out_drop_write;
1998 }
1999
2000 if (copy_from_user(&flags, arg, sizeof(flags))) {
2001 ret = -EFAULT;
2002 goto out_drop_write;
2003 }
2004
2005 if (flags & ~BTRFS_SUBVOL_RDONLY) {
2006 ret = -EOPNOTSUPP;
2007 goto out_drop_write;
2008 }
2009
2010 down_write(&fs_info->subvol_sem);
2011
2012 /* nothing to do */
2013 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
2014 goto out_drop_sem;
2015
2016 root_flags = btrfs_root_flags(&root->root_item);
2017 if (flags & BTRFS_SUBVOL_RDONLY) {
2018 btrfs_set_root_flags(&root->root_item,
2019 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
2020 } else {
2021 /*
2022 * Block RO -> RW transition if this subvolume is involved in
2023 * send
2024 */
2025 spin_lock(&root->root_item_lock);
2026 if (root->send_in_progress == 0) {
2027 btrfs_set_root_flags(&root->root_item,
2028 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
2029 spin_unlock(&root->root_item_lock);
2030 } else {
2031 spin_unlock(&root->root_item_lock);
2032 btrfs_warn(fs_info,
2033 "Attempt to set subvolume %llu read-write during send",
2034 root->root_key.objectid);
2035 ret = -EPERM;
2036 goto out_drop_sem;
2037 }
2038 }
2039
2040 trans = btrfs_start_transaction(root, 1);
2041 if (IS_ERR(trans)) {
2042 ret = PTR_ERR(trans);
2043 goto out_reset;
2044 }
2045
2046 ret = btrfs_update_root(trans, fs_info->tree_root,
2047 &root->root_key, &root->root_item);
2048 if (ret < 0) {
2049 btrfs_end_transaction(trans);
2050 goto out_reset;
2051 }
2052
2053 ret = btrfs_commit_transaction(trans);
2054
2055 out_reset:
2056 if (ret)
2057 btrfs_set_root_flags(&root->root_item, root_flags);
2058 out_drop_sem:
2059 up_write(&fs_info->subvol_sem);
2060 out_drop_write:
2061 mnt_drop_write_file(file);
2062 out:
2063 return ret;
2064 }
2065
2066 static noinline int key_in_sk(struct btrfs_key *key,
2067 struct btrfs_ioctl_search_key *sk)
2068 {
2069 struct btrfs_key test;
2070 int ret;
2071
2072 test.objectid = sk->min_objectid;
2073 test.type = sk->min_type;
2074 test.offset = sk->min_offset;
2075
2076 ret = btrfs_comp_cpu_keys(key, &test);
2077 if (ret < 0)
2078 return 0;
2079
2080 test.objectid = sk->max_objectid;
2081 test.type = sk->max_type;
2082 test.offset = sk->max_offset;
2083
2084 ret = btrfs_comp_cpu_keys(key, &test);
2085 if (ret > 0)
2086 return 0;
2087 return 1;
2088 }
2089
2090 static noinline int copy_to_sk(struct btrfs_path *path,
2091 struct btrfs_key *key,
2092 struct btrfs_ioctl_search_key *sk,
2093 size_t *buf_size,
2094 char __user *ubuf,
2095 unsigned long *sk_offset,
2096 int *num_found)
2097 {
2098 u64 found_transid;
2099 struct extent_buffer *leaf;
2100 struct btrfs_ioctl_search_header sh;
2101 struct btrfs_key test;
2102 unsigned long item_off;
2103 unsigned long item_len;
2104 int nritems;
2105 int i;
2106 int slot;
2107 int ret = 0;
2108
2109 leaf = path->nodes[0];
2110 slot = path->slots[0];
2111 nritems = btrfs_header_nritems(leaf);
2112
2113 if (btrfs_header_generation(leaf) > sk->max_transid) {
2114 i = nritems;
2115 goto advance_key;
2116 }
2117 found_transid = btrfs_header_generation(leaf);
2118
2119 for (i = slot; i < nritems; i++) {
2120 item_off = btrfs_item_ptr_offset(leaf, i);
2121 item_len = btrfs_item_size_nr(leaf, i);
2122
2123 btrfs_item_key_to_cpu(leaf, key, i);
2124 if (!key_in_sk(key, sk))
2125 continue;
2126
2127 if (sizeof(sh) + item_len > *buf_size) {
2128 if (*num_found) {
2129 ret = 1;
2130 goto out;
2131 }
2132
2133 /*
2134 * return one empty item back for v1, which does not
2135 * handle -EOVERFLOW
2136 */
2137
2138 *buf_size = sizeof(sh) + item_len;
2139 item_len = 0;
2140 ret = -EOVERFLOW;
2141 }
2142
2143 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2144 ret = 1;
2145 goto out;
2146 }
2147
2148 sh.objectid = key->objectid;
2149 sh.offset = key->offset;
2150 sh.type = key->type;
2151 sh.len = item_len;
2152 sh.transid = found_transid;
2153
2154 /*
2155 * Copy search result header. If we fault then loop again so we
2156 * can fault in the pages and -EFAULT there if there's a
2157 * problem. Otherwise we'll fault and then copy the buffer in
2158 * properly this next time through
2159 */
2160 if (copy_to_user_nofault(ubuf + *sk_offset, &sh, sizeof(sh))) {
2161 ret = 0;
2162 goto out;
2163 }
2164
2165 *sk_offset += sizeof(sh);
2166
2167 if (item_len) {
2168 char __user *up = ubuf + *sk_offset;
2169 /*
2170 * Copy the item, same behavior as above, but reset the
2171 * * sk_offset so we copy the full thing again.
2172 */
2173 if (read_extent_buffer_to_user_nofault(leaf, up,
2174 item_off, item_len)) {
2175 ret = 0;
2176 *sk_offset -= sizeof(sh);
2177 goto out;
2178 }
2179
2180 *sk_offset += item_len;
2181 }
2182 (*num_found)++;
2183
2184 if (ret) /* -EOVERFLOW from above */
2185 goto out;
2186
2187 if (*num_found >= sk->nr_items) {
2188 ret = 1;
2189 goto out;
2190 }
2191 }
2192 advance_key:
2193 ret = 0;
2194 test.objectid = sk->max_objectid;
2195 test.type = sk->max_type;
2196 test.offset = sk->max_offset;
2197 if (btrfs_comp_cpu_keys(key, &test) >= 0)
2198 ret = 1;
2199 else if (key->offset < (u64)-1)
2200 key->offset++;
2201 else if (key->type < (u8)-1) {
2202 key->offset = 0;
2203 key->type++;
2204 } else if (key->objectid < (u64)-1) {
2205 key->offset = 0;
2206 key->type = 0;
2207 key->objectid++;
2208 } else
2209 ret = 1;
2210 out:
2211 /*
2212 * 0: all items from this leaf copied, continue with next
2213 * 1: * more items can be copied, but unused buffer is too small
2214 * * all items were found
2215 * Either way, it will stops the loop which iterates to the next
2216 * leaf
2217 * -EOVERFLOW: item was to large for buffer
2218 * -EFAULT: could not copy extent buffer back to userspace
2219 */
2220 return ret;
2221 }
2222
2223 static noinline int search_ioctl(struct inode *inode,
2224 struct btrfs_ioctl_search_key *sk,
2225 size_t *buf_size,
2226 char __user *ubuf)
2227 {
2228 struct btrfs_fs_info *info = btrfs_sb(inode->i_sb);
2229 struct btrfs_root *root;
2230 struct btrfs_key key;
2231 struct btrfs_path *path;
2232 int ret;
2233 int num_found = 0;
2234 unsigned long sk_offset = 0;
2235
2236 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2237 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2238 return -EOVERFLOW;
2239 }
2240
2241 path = btrfs_alloc_path();
2242 if (!path)
2243 return -ENOMEM;
2244
2245 if (sk->tree_id == 0) {
2246 /* search the root of the inode that was passed */
2247 root = btrfs_grab_root(BTRFS_I(inode)->root);
2248 } else {
2249 root = btrfs_get_fs_root(info, sk->tree_id, true);
2250 if (IS_ERR(root)) {
2251 btrfs_free_path(path);
2252 return PTR_ERR(root);
2253 }
2254 }
2255
2256 key.objectid = sk->min_objectid;
2257 key.type = sk->min_type;
2258 key.offset = sk->min_offset;
2259
2260 while (1) {
2261 ret = fault_in_pages_writeable(ubuf + sk_offset,
2262 *buf_size - sk_offset);
2263 if (ret)
2264 break;
2265
2266 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2267 if (ret != 0) {
2268 if (ret > 0)
2269 ret = 0;
2270 goto err;
2271 }
2272 ret = copy_to_sk(path, &key, sk, buf_size, ubuf,
2273 &sk_offset, &num_found);
2274 btrfs_release_path(path);
2275 if (ret)
2276 break;
2277
2278 }
2279 if (ret > 0)
2280 ret = 0;
2281 err:
2282 sk->nr_items = num_found;
2283 btrfs_put_root(root);
2284 btrfs_free_path(path);
2285 return ret;
2286 }
2287
2288 static noinline int btrfs_ioctl_tree_search(struct file *file,
2289 void __user *argp)
2290 {
2291 struct btrfs_ioctl_search_args __user *uargs;
2292 struct btrfs_ioctl_search_key sk;
2293 struct inode *inode;
2294 int ret;
2295 size_t buf_size;
2296
2297 if (!capable(CAP_SYS_ADMIN))
2298 return -EPERM;
2299
2300 uargs = (struct btrfs_ioctl_search_args __user *)argp;
2301
2302 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2303 return -EFAULT;
2304
2305 buf_size = sizeof(uargs->buf);
2306
2307 inode = file_inode(file);
2308 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2309
2310 /*
2311 * In the origin implementation an overflow is handled by returning a
2312 * search header with a len of zero, so reset ret.
2313 */
2314 if (ret == -EOVERFLOW)
2315 ret = 0;
2316
2317 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2318 ret = -EFAULT;
2319 return ret;
2320 }
2321
2322 static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2323 void __user *argp)
2324 {
2325 struct btrfs_ioctl_search_args_v2 __user *uarg;
2326 struct btrfs_ioctl_search_args_v2 args;
2327 struct inode *inode;
2328 int ret;
2329 size_t buf_size;
2330 const size_t buf_limit = SZ_16M;
2331
2332 if (!capable(CAP_SYS_ADMIN))
2333 return -EPERM;
2334
2335 /* copy search header and buffer size */
2336 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2337 if (copy_from_user(&args, uarg, sizeof(args)))
2338 return -EFAULT;
2339
2340 buf_size = args.buf_size;
2341
2342 /* limit result size to 16MB */
2343 if (buf_size > buf_limit)
2344 buf_size = buf_limit;
2345
2346 inode = file_inode(file);
2347 ret = search_ioctl(inode, &args.key, &buf_size,
2348 (char __user *)(&uarg->buf[0]));
2349 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2350 ret = -EFAULT;
2351 else if (ret == -EOVERFLOW &&
2352 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2353 ret = -EFAULT;
2354
2355 return ret;
2356 }
2357
2358 /*
2359 * Search INODE_REFs to identify path name of 'dirid' directory
2360 * in a 'tree_id' tree. and sets path name to 'name'.
2361 */
2362 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2363 u64 tree_id, u64 dirid, char *name)
2364 {
2365 struct btrfs_root *root;
2366 struct btrfs_key key;
2367 char *ptr;
2368 int ret = -1;
2369 int slot;
2370 int len;
2371 int total_len = 0;
2372 struct btrfs_inode_ref *iref;
2373 struct extent_buffer *l;
2374 struct btrfs_path *path;
2375
2376 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2377 name[0]='\0';
2378 return 0;
2379 }
2380
2381 path = btrfs_alloc_path();
2382 if (!path)
2383 return -ENOMEM;
2384
2385 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1];
2386
2387 root = btrfs_get_fs_root(info, tree_id, true);
2388 if (IS_ERR(root)) {
2389 ret = PTR_ERR(root);
2390 root = NULL;
2391 goto out;
2392 }
2393
2394 key.objectid = dirid;
2395 key.type = BTRFS_INODE_REF_KEY;
2396 key.offset = (u64)-1;
2397
2398 while (1) {
2399 ret = btrfs_search_backwards(root, &key, path);
2400 if (ret < 0)
2401 goto out;
2402 else if (ret > 0) {
2403 ret = -ENOENT;
2404 goto out;
2405 }
2406
2407 l = path->nodes[0];
2408 slot = path->slots[0];
2409
2410 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2411 len = btrfs_inode_ref_name_len(l, iref);
2412 ptr -= len + 1;
2413 total_len += len + 1;
2414 if (ptr < name) {
2415 ret = -ENAMETOOLONG;
2416 goto out;
2417 }
2418
2419 *(ptr + len) = '/';
2420 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2421
2422 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2423 break;
2424
2425 btrfs_release_path(path);
2426 key.objectid = key.offset;
2427 key.offset = (u64)-1;
2428 dirid = key.objectid;
2429 }
2430 memmove(name, ptr, total_len);
2431 name[total_len] = '\0';
2432 ret = 0;
2433 out:
2434 btrfs_put_root(root);
2435 btrfs_free_path(path);
2436 return ret;
2437 }
2438
2439 static int btrfs_search_path_in_tree_user(struct user_namespace *mnt_userns,
2440 struct inode *inode,
2441 struct btrfs_ioctl_ino_lookup_user_args *args)
2442 {
2443 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2444 struct super_block *sb = inode->i_sb;
2445 struct btrfs_key upper_limit = BTRFS_I(inode)->location;
2446 u64 treeid = BTRFS_I(inode)->root->root_key.objectid;
2447 u64 dirid = args->dirid;
2448 unsigned long item_off;
2449 unsigned long item_len;
2450 struct btrfs_inode_ref *iref;
2451 struct btrfs_root_ref *rref;
2452 struct btrfs_root *root = NULL;
2453 struct btrfs_path *path;
2454 struct btrfs_key key, key2;
2455 struct extent_buffer *leaf;
2456 struct inode *temp_inode;
2457 char *ptr;
2458 int slot;
2459 int len;
2460 int total_len = 0;
2461 int ret;
2462
2463 path = btrfs_alloc_path();
2464 if (!path)
2465 return -ENOMEM;
2466
2467 /*
2468 * If the bottom subvolume does not exist directly under upper_limit,
2469 * construct the path in from the bottom up.
2470 */
2471 if (dirid != upper_limit.objectid) {
2472 ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1];
2473
2474 root = btrfs_get_fs_root(fs_info, treeid, true);
2475 if (IS_ERR(root)) {
2476 ret = PTR_ERR(root);
2477 goto out;
2478 }
2479
2480 key.objectid = dirid;
2481 key.type = BTRFS_INODE_REF_KEY;
2482 key.offset = (u64)-1;
2483 while (1) {
2484 ret = btrfs_search_backwards(root, &key, path);
2485 if (ret < 0)
2486 goto out_put;
2487 else if (ret > 0) {
2488 ret = -ENOENT;
2489 goto out_put;
2490 }
2491
2492 leaf = path->nodes[0];
2493 slot = path->slots[0];
2494
2495 iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref);
2496 len = btrfs_inode_ref_name_len(leaf, iref);
2497 ptr -= len + 1;
2498 total_len += len + 1;
2499 if (ptr < args->path) {
2500 ret = -ENAMETOOLONG;
2501 goto out_put;
2502 }
2503
2504 *(ptr + len) = '/';
2505 read_extent_buffer(leaf, ptr,
2506 (unsigned long)(iref + 1), len);
2507
2508 /* Check the read+exec permission of this directory */
2509 ret = btrfs_previous_item(root, path, dirid,
2510 BTRFS_INODE_ITEM_KEY);
2511 if (ret < 0) {
2512 goto out_put;
2513 } else if (ret > 0) {
2514 ret = -ENOENT;
2515 goto out_put;
2516 }
2517
2518 leaf = path->nodes[0];
2519 slot = path->slots[0];
2520 btrfs_item_key_to_cpu(leaf, &key2, slot);
2521 if (key2.objectid != dirid) {
2522 ret = -ENOENT;
2523 goto out_put;
2524 }
2525
2526 temp_inode = btrfs_iget(sb, key2.objectid, root);
2527 if (IS_ERR(temp_inode)) {
2528 ret = PTR_ERR(temp_inode);
2529 goto out_put;
2530 }
2531 ret = inode_permission(mnt_userns, temp_inode,
2532 MAY_READ | MAY_EXEC);
2533 iput(temp_inode);
2534 if (ret) {
2535 ret = -EACCES;
2536 goto out_put;
2537 }
2538
2539 if (key.offset == upper_limit.objectid)
2540 break;
2541 if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {
2542 ret = -EACCES;
2543 goto out_put;
2544 }
2545
2546 btrfs_release_path(path);
2547 key.objectid = key.offset;
2548 key.offset = (u64)-1;
2549 dirid = key.objectid;
2550 }
2551
2552 memmove(args->path, ptr, total_len);
2553 args->path[total_len] = '\0';
2554 btrfs_put_root(root);
2555 root = NULL;
2556 btrfs_release_path(path);
2557 }
2558
2559 /* Get the bottom subvolume's name from ROOT_REF */
2560 key.objectid = treeid;
2561 key.type = BTRFS_ROOT_REF_KEY;
2562 key.offset = args->treeid;
2563 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
2564 if (ret < 0) {
2565 goto out;
2566 } else if (ret > 0) {
2567 ret = -ENOENT;
2568 goto out;
2569 }
2570
2571 leaf = path->nodes[0];
2572 slot = path->slots[0];
2573 btrfs_item_key_to_cpu(leaf, &key, slot);
2574
2575 item_off = btrfs_item_ptr_offset(leaf, slot);
2576 item_len = btrfs_item_size_nr(leaf, slot);
2577 /* Check if dirid in ROOT_REF corresponds to passed dirid */
2578 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2579 if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) {
2580 ret = -EINVAL;
2581 goto out;
2582 }
2583
2584 /* Copy subvolume's name */
2585 item_off += sizeof(struct btrfs_root_ref);
2586 item_len -= sizeof(struct btrfs_root_ref);
2587 read_extent_buffer(leaf, args->name, item_off, item_len);
2588 args->name[item_len] = 0;
2589
2590 out_put:
2591 btrfs_put_root(root);
2592 out:
2593 btrfs_free_path(path);
2594 return ret;
2595 }
2596
2597 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2598 void __user *argp)
2599 {
2600 struct btrfs_ioctl_ino_lookup_args *args;
2601 struct inode *inode;
2602 int ret = 0;
2603
2604 args = memdup_user(argp, sizeof(*args));
2605 if (IS_ERR(args))
2606 return PTR_ERR(args);
2607
2608 inode = file_inode(file);
2609
2610 /*
2611 * Unprivileged query to obtain the containing subvolume root id. The
2612 * path is reset so it's consistent with btrfs_search_path_in_tree.
2613 */
2614 if (args->treeid == 0)
2615 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2616
2617 if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2618 args->name[0] = 0;
2619 goto out;
2620 }
2621
2622 if (!capable(CAP_SYS_ADMIN)) {
2623 ret = -EPERM;
2624 goto out;
2625 }
2626
2627 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2628 args->treeid, args->objectid,
2629 args->name);
2630
2631 out:
2632 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2633 ret = -EFAULT;
2634
2635 kfree(args);
2636 return ret;
2637 }
2638
2639 /*
2640 * Version of ino_lookup ioctl (unprivileged)
2641 *
2642 * The main differences from ino_lookup ioctl are:
2643 *
2644 * 1. Read + Exec permission will be checked using inode_permission() during
2645 * path construction. -EACCES will be returned in case of failure.
2646 * 2. Path construction will be stopped at the inode number which corresponds
2647 * to the fd with which this ioctl is called. If constructed path does not
2648 * exist under fd's inode, -EACCES will be returned.
2649 * 3. The name of bottom subvolume is also searched and filled.
2650 */
2651 static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp)
2652 {
2653 struct btrfs_ioctl_ino_lookup_user_args *args;
2654 struct inode *inode;
2655 int ret;
2656
2657 args = memdup_user(argp, sizeof(*args));
2658 if (IS_ERR(args))
2659 return PTR_ERR(args);
2660
2661 inode = file_inode(file);
2662
2663 if (args->dirid == BTRFS_FIRST_FREE_OBJECTID &&
2664 BTRFS_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) {
2665 /*
2666 * The subvolume does not exist under fd with which this is
2667 * called
2668 */
2669 kfree(args);
2670 return -EACCES;
2671 }
2672
2673 ret = btrfs_search_path_in_tree_user(file_mnt_user_ns(file), inode, args);
2674
2675 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2676 ret = -EFAULT;
2677
2678 kfree(args);
2679 return ret;
2680 }
2681
2682 /* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */
2683 static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp)
2684 {
2685 struct btrfs_ioctl_get_subvol_info_args *subvol_info;
2686 struct btrfs_fs_info *fs_info;
2687 struct btrfs_root *root;
2688 struct btrfs_path *path;
2689 struct btrfs_key key;
2690 struct btrfs_root_item *root_item;
2691 struct btrfs_root_ref *rref;
2692 struct extent_buffer *leaf;
2693 unsigned long item_off;
2694 unsigned long item_len;
2695 struct inode *inode;
2696 int slot;
2697 int ret = 0;
2698
2699 path = btrfs_alloc_path();
2700 if (!path)
2701 return -ENOMEM;
2702
2703 subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL);
2704 if (!subvol_info) {
2705 btrfs_free_path(path);
2706 return -ENOMEM;
2707 }
2708
2709 inode = file_inode(file);
2710 fs_info = BTRFS_I(inode)->root->fs_info;
2711
2712 /* Get root_item of inode's subvolume */
2713 key.objectid = BTRFS_I(inode)->root->root_key.objectid;
2714 root = btrfs_get_fs_root(fs_info, key.objectid, true);
2715 if (IS_ERR(root)) {
2716 ret = PTR_ERR(root);
2717 goto out_free;
2718 }
2719 root_item = &root->root_item;
2720
2721 subvol_info->treeid = key.objectid;
2722
2723 subvol_info->generation = btrfs_root_generation(root_item);
2724 subvol_info->flags = btrfs_root_flags(root_item);
2725
2726 memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE);
2727 memcpy(subvol_info->parent_uuid, root_item->parent_uuid,
2728 BTRFS_UUID_SIZE);
2729 memcpy(subvol_info->received_uuid, root_item->received_uuid,
2730 BTRFS_UUID_SIZE);
2731
2732 subvol_info->ctransid = btrfs_root_ctransid(root_item);
2733 subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime);
2734 subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime);
2735
2736 subvol_info->otransid = btrfs_root_otransid(root_item);
2737 subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime);
2738 subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime);
2739
2740 subvol_info->stransid = btrfs_root_stransid(root_item);
2741 subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime);
2742 subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime);
2743
2744 subvol_info->rtransid = btrfs_root_rtransid(root_item);
2745 subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime);
2746 subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime);
2747
2748 if (key.objectid != BTRFS_FS_TREE_OBJECTID) {
2749 /* Search root tree for ROOT_BACKREF of this subvolume */
2750 key.type = BTRFS_ROOT_BACKREF_KEY;
2751 key.offset = 0;
2752 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
2753 if (ret < 0) {
2754 goto out;
2755 } else if (path->slots[0] >=
2756 btrfs_header_nritems(path->nodes[0])) {
2757 ret = btrfs_next_leaf(fs_info->tree_root, path);
2758 if (ret < 0) {
2759 goto out;
2760 } else if (ret > 0) {
2761 ret = -EUCLEAN;
2762 goto out;
2763 }
2764 }
2765
2766 leaf = path->nodes[0];
2767 slot = path->slots[0];
2768 btrfs_item_key_to_cpu(leaf, &key, slot);
2769 if (key.objectid == subvol_info->treeid &&
2770 key.type == BTRFS_ROOT_BACKREF_KEY) {
2771 subvol_info->parent_id = key.offset;
2772
2773 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2774 subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref);
2775
2776 item_off = btrfs_item_ptr_offset(leaf, slot)
2777 + sizeof(struct btrfs_root_ref);
2778 item_len = btrfs_item_size_nr(leaf, slot)
2779 - sizeof(struct btrfs_root_ref);
2780 read_extent_buffer(leaf, subvol_info->name,
2781 item_off, item_len);
2782 } else {
2783 ret = -ENOENT;
2784 goto out;
2785 }
2786 }
2787
2788 if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))
2789 ret = -EFAULT;
2790
2791 out:
2792 btrfs_put_root(root);
2793 out_free:
2794 btrfs_free_path(path);
2795 kfree(subvol_info);
2796 return ret;
2797 }
2798
2799 /*
2800 * Return ROOT_REF information of the subvolume containing this inode
2801 * except the subvolume name.
2802 */
2803 static int btrfs_ioctl_get_subvol_rootref(struct file *file, void __user *argp)
2804 {
2805 struct btrfs_ioctl_get_subvol_rootref_args *rootrefs;
2806 struct btrfs_root_ref *rref;
2807 struct btrfs_root *root;
2808 struct btrfs_path *path;
2809 struct btrfs_key key;
2810 struct extent_buffer *leaf;
2811 struct inode *inode;
2812 u64 objectid;
2813 int slot;
2814 int ret;
2815 u8 found;
2816
2817 path = btrfs_alloc_path();
2818 if (!path)
2819 return -ENOMEM;
2820
2821 rootrefs = memdup_user(argp, sizeof(*rootrefs));
2822 if (IS_ERR(rootrefs)) {
2823 btrfs_free_path(path);
2824 return PTR_ERR(rootrefs);
2825 }
2826
2827 inode = file_inode(file);
2828 root = BTRFS_I(inode)->root->fs_info->tree_root;
2829 objectid = BTRFS_I(inode)->root->root_key.objectid;
2830
2831 key.objectid = objectid;
2832 key.type = BTRFS_ROOT_REF_KEY;
2833 key.offset = rootrefs->min_treeid;
2834 found = 0;
2835
2836 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2837 if (ret < 0) {
2838 goto out;
2839 } else if (path->slots[0] >=
2840 btrfs_header_nritems(path->nodes[0])) {
2841 ret = btrfs_next_leaf(root, path);
2842 if (ret < 0) {
2843 goto out;
2844 } else if (ret > 0) {
2845 ret = -EUCLEAN;
2846 goto out;
2847 }
2848 }
2849 while (1) {
2850 leaf = path->nodes[0];
2851 slot = path->slots[0];
2852
2853 btrfs_item_key_to_cpu(leaf, &key, slot);
2854 if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) {
2855 ret = 0;
2856 goto out;
2857 }
2858
2859 if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) {
2860 ret = -EOVERFLOW;
2861 goto out;
2862 }
2863
2864 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2865 rootrefs->rootref[found].treeid = key.offset;
2866 rootrefs->rootref[found].dirid =
2867 btrfs_root_ref_dirid(leaf, rref);
2868 found++;
2869
2870 ret = btrfs_next_item(root, path);
2871 if (ret < 0) {
2872 goto out;
2873 } else if (ret > 0) {
2874 ret = -EUCLEAN;
2875 goto out;
2876 }
2877 }
2878
2879 out:
2880 if (!ret || ret == -EOVERFLOW) {
2881 rootrefs->num_items = found;
2882 /* update min_treeid for next search */
2883 if (found)
2884 rootrefs->min_treeid =
2885 rootrefs->rootref[found - 1].treeid + 1;
2886 if (copy_to_user(argp, rootrefs, sizeof(*rootrefs)))
2887 ret = -EFAULT;
2888 }
2889
2890 kfree(rootrefs);
2891 btrfs_free_path(path);
2892
2893 return ret;
2894 }
2895
2896 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2897 void __user *arg,
2898 bool destroy_v2)
2899 {
2900 struct dentry *parent = file->f_path.dentry;
2901 struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb);
2902 struct dentry *dentry;
2903 struct inode *dir = d_inode(parent);
2904 struct inode *inode;
2905 struct btrfs_root *root = BTRFS_I(dir)->root;
2906 struct btrfs_root *dest = NULL;
2907 struct btrfs_ioctl_vol_args *vol_args = NULL;
2908 struct btrfs_ioctl_vol_args_v2 *vol_args2 = NULL;
2909 struct user_namespace *mnt_userns = file_mnt_user_ns(file);
2910 char *subvol_name, *subvol_name_ptr = NULL;
2911 int subvol_namelen;
2912 int err = 0;
2913 bool destroy_parent = false;
2914
2915 if (destroy_v2) {
2916 vol_args2 = memdup_user(arg, sizeof(*vol_args2));
2917 if (IS_ERR(vol_args2))
2918 return PTR_ERR(vol_args2);
2919
2920 if (vol_args2->flags & ~BTRFS_SUBVOL_DELETE_ARGS_MASK) {
2921 err = -EOPNOTSUPP;
2922 goto out;
2923 }
2924
2925 /*
2926 * If SPEC_BY_ID is not set, we are looking for the subvolume by
2927 * name, same as v1 currently does.
2928 */
2929 if (!(vol_args2->flags & BTRFS_SUBVOL_SPEC_BY_ID)) {
2930 vol_args2->name[BTRFS_SUBVOL_NAME_MAX] = 0;
2931 subvol_name = vol_args2->name;
2932
2933 err = mnt_want_write_file(file);
2934 if (err)
2935 goto out;
2936 } else {
2937 struct inode *old_dir;
2938
2939 if (vol_args2->subvolid < BTRFS_FIRST_FREE_OBJECTID) {
2940 err = -EINVAL;
2941 goto out;
2942 }
2943
2944 err = mnt_want_write_file(file);
2945 if (err)
2946 goto out;
2947
2948 dentry = btrfs_get_dentry(fs_info->sb,
2949 BTRFS_FIRST_FREE_OBJECTID,
2950 vol_args2->subvolid, 0, 0);
2951 if (IS_ERR(dentry)) {
2952 err = PTR_ERR(dentry);
2953 goto out_drop_write;
2954 }
2955
2956 /*
2957 * Change the default parent since the subvolume being
2958 * deleted can be outside of the current mount point.
2959 */
2960 parent = btrfs_get_parent(dentry);
2961
2962 /*
2963 * At this point dentry->d_name can point to '/' if the
2964 * subvolume we want to destroy is outsite of the
2965 * current mount point, so we need to release the
2966 * current dentry and execute the lookup to return a new
2967 * one with ->d_name pointing to the
2968 * <mount point>/subvol_name.
2969 */
2970 dput(dentry);
2971 if (IS_ERR(parent)) {
2972 err = PTR_ERR(parent);
2973 goto out_drop_write;
2974 }
2975 old_dir = dir;
2976 dir = d_inode(parent);
2977
2978 /*
2979 * If v2 was used with SPEC_BY_ID, a new parent was
2980 * allocated since the subvolume can be outside of the
2981 * current mount point. Later on we need to release this
2982 * new parent dentry.
2983 */
2984 destroy_parent = true;
2985
2986 /*
2987 * On idmapped mounts, deletion via subvolid is
2988 * restricted to subvolumes that are immediate
2989 * ancestors of the inode referenced by the file
2990 * descriptor in the ioctl. Otherwise the idmapping
2991 * could potentially be abused to delete subvolumes
2992 * anywhere in the filesystem the user wouldn't be able
2993 * to delete without an idmapped mount.
2994 */
2995 if (old_dir != dir && mnt_userns != &init_user_ns) {
2996 err = -EOPNOTSUPP;
2997 goto free_parent;
2998 }
2999
3000 subvol_name_ptr = btrfs_get_subvol_name_from_objectid(
3001 fs_info, vol_args2->subvolid);
3002 if (IS_ERR(subvol_name_ptr)) {
3003 err = PTR_ERR(subvol_name_ptr);
3004 goto free_parent;
3005 }
3006 /* subvol_name_ptr is already nul terminated */
3007 subvol_name = (char *)kbasename(subvol_name_ptr);
3008 }
3009 } else {
3010 vol_args = memdup_user(arg, sizeof(*vol_args));
3011 if (IS_ERR(vol_args))
3012 return PTR_ERR(vol_args);
3013
3014 vol_args->name[BTRFS_PATH_NAME_MAX] = 0;
3015 subvol_name = vol_args->name;
3016
3017 err = mnt_want_write_file(file);
3018 if (err)
3019 goto out;
3020 }
3021
3022 subvol_namelen = strlen(subvol_name);
3023
3024 if (strchr(subvol_name, '/') ||
3025 strncmp(subvol_name, "..", subvol_namelen) == 0) {
3026 err = -EINVAL;
3027 goto free_subvol_name;
3028 }
3029
3030 if (!S_ISDIR(dir->i_mode)) {
3031 err = -ENOTDIR;
3032 goto free_subvol_name;
3033 }
3034
3035 err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
3036 if (err == -EINTR)
3037 goto free_subvol_name;
3038 dentry = lookup_one(mnt_userns, subvol_name, parent, subvol_namelen);
3039 if (IS_ERR(dentry)) {
3040 err = PTR_ERR(dentry);
3041 goto out_unlock_dir;
3042 }
3043
3044 if (d_really_is_negative(dentry)) {
3045 err = -ENOENT;
3046 goto out_dput;
3047 }
3048
3049 inode = d_inode(dentry);
3050 dest = BTRFS_I(inode)->root;
3051 if (!capable(CAP_SYS_ADMIN)) {
3052 /*
3053 * Regular user. Only allow this with a special mount
3054 * option, when the user has write+exec access to the
3055 * subvol root, and when rmdir(2) would have been
3056 * allowed.
3057 *
3058 * Note that this is _not_ check that the subvol is
3059 * empty or doesn't contain data that we wouldn't
3060 * otherwise be able to delete.
3061 *
3062 * Users who want to delete empty subvols should try
3063 * rmdir(2).
3064 */
3065 err = -EPERM;
3066 if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))
3067 goto out_dput;
3068
3069 /*
3070 * Do not allow deletion if the parent dir is the same
3071 * as the dir to be deleted. That means the ioctl
3072 * must be called on the dentry referencing the root
3073 * of the subvol, not a random directory contained
3074 * within it.
3075 */
3076 err = -EINVAL;
3077 if (root == dest)
3078 goto out_dput;
3079
3080 err = inode_permission(mnt_userns, inode, MAY_WRITE | MAY_EXEC);
3081 if (err)
3082 goto out_dput;
3083 }
3084
3085 /* check if subvolume may be deleted by a user */
3086 err = btrfs_may_delete(mnt_userns, dir, dentry, 1);
3087 if (err)
3088 goto out_dput;
3089
3090 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
3091 err = -EINVAL;
3092 goto out_dput;
3093 }
3094
3095 btrfs_inode_lock(inode, 0);
3096 err = btrfs_delete_subvolume(dir, dentry);
3097 btrfs_inode_unlock(inode, 0);
3098 if (!err)
3099 d_delete_notify(dir, dentry);
3100
3101 out_dput:
3102 dput(dentry);
3103 out_unlock_dir:
3104 btrfs_inode_unlock(dir, 0);
3105 free_subvol_name:
3106 kfree(subvol_name_ptr);
3107 free_parent:
3108 if (destroy_parent)
3109 dput(parent);
3110 out_drop_write:
3111 mnt_drop_write_file(file);
3112 out:
3113 kfree(vol_args2);
3114 kfree(vol_args);
3115 return err;
3116 }
3117
3118 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
3119 {
3120 struct inode *inode = file_inode(file);
3121 struct btrfs_root *root = BTRFS_I(inode)->root;
3122 struct btrfs_ioctl_defrag_range_args range = {0};
3123 int ret;
3124
3125 ret = mnt_want_write_file(file);
3126 if (ret)
3127 return ret;
3128
3129 if (btrfs_root_readonly(root)) {
3130 ret = -EROFS;
3131 goto out;
3132 }
3133
3134 /* Subpage defrag will be supported in later commits */
3135 if (root->fs_info->sectorsize < PAGE_SIZE) {
3136 ret = -ENOTTY;
3137 goto out;
3138 }
3139
3140 switch (inode->i_mode & S_IFMT) {
3141 case S_IFDIR:
3142 if (!capable(CAP_SYS_ADMIN)) {
3143 ret = -EPERM;
3144 goto out;
3145 }
3146 ret = btrfs_defrag_root(root);
3147 break;
3148 case S_IFREG:
3149 /*
3150 * Note that this does not check the file descriptor for write
3151 * access. This prevents defragmenting executables that are
3152 * running and allows defrag on files open in read-only mode.
3153 */
3154 if (!capable(CAP_SYS_ADMIN) &&
3155 inode_permission(&init_user_ns, inode, MAY_WRITE)) {
3156 ret = -EPERM;
3157 goto out;
3158 }
3159
3160 if (argp) {
3161 if (copy_from_user(&range, argp, sizeof(range))) {
3162 ret = -EFAULT;
3163 goto out;
3164 }
3165 /* compression requires us to start the IO */
3166 if ((range.flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
3167 range.flags |= BTRFS_DEFRAG_RANGE_START_IO;
3168 range.extent_thresh = (u32)-1;
3169 }
3170 } else {
3171 /* the rest are all set to zero by kzalloc */
3172 range.len = (u64)-1;
3173 }
3174 ret = btrfs_defrag_file(file_inode(file), file,
3175 &range, BTRFS_OLDEST_GENERATION, 0);
3176 if (ret > 0)
3177 ret = 0;
3178 break;
3179 default:
3180 ret = -EINVAL;
3181 }
3182 out:
3183 mnt_drop_write_file(file);
3184 return ret;
3185 }
3186
3187 static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg)
3188 {
3189 struct btrfs_ioctl_vol_args *vol_args;
3190 int ret;
3191
3192 if (!capable(CAP_SYS_ADMIN))
3193 return -EPERM;
3194
3195 if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_ADD))
3196 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3197
3198 vol_args = memdup_user(arg, sizeof(*vol_args));
3199 if (IS_ERR(vol_args)) {
3200 ret = PTR_ERR(vol_args);
3201 goto out;
3202 }
3203
3204 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3205 ret = btrfs_init_new_device(fs_info, vol_args->name);
3206
3207 if (!ret)
3208 btrfs_info(fs_info, "disk added %s", vol_args->name);
3209
3210 kfree(vol_args);
3211 out:
3212 btrfs_exclop_finish(fs_info);
3213 return ret;
3214 }
3215
3216 static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
3217 {
3218 struct inode *inode = file_inode(file);
3219 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3220 struct btrfs_ioctl_vol_args_v2 *vol_args;
3221 struct block_device *bdev = NULL;
3222 fmode_t mode;
3223 int ret;
3224 bool cancel = false;
3225
3226 if (!capable(CAP_SYS_ADMIN))
3227 return -EPERM;
3228
3229 ret = mnt_want_write_file(file);
3230 if (ret)
3231 return ret;
3232
3233 vol_args = memdup_user(arg, sizeof(*vol_args));
3234 if (IS_ERR(vol_args)) {
3235 ret = PTR_ERR(vol_args);
3236 goto err_drop;
3237 }
3238
3239 if (vol_args->flags & ~BTRFS_DEVICE_REMOVE_ARGS_MASK) {
3240 ret = -EOPNOTSUPP;
3241 goto out;
3242 }
3243 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
3244 if (!(vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) &&
3245 strcmp("cancel", vol_args->name) == 0)
3246 cancel = true;
3247
3248 ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,
3249 cancel);
3250 if (ret)
3251 goto out;
3252 /* Exclusive operation is now claimed */
3253
3254 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
3255 ret = btrfs_rm_device(fs_info, NULL, vol_args->devid, &bdev, &mode);
3256 else
3257 ret = btrfs_rm_device(fs_info, vol_args->name, 0, &bdev, &mode);
3258
3259 btrfs_exclop_finish(fs_info);
3260
3261 if (!ret) {
3262 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
3263 btrfs_info(fs_info, "device deleted: id %llu",
3264 vol_args->devid);
3265 else
3266 btrfs_info(fs_info, "device deleted: %s",
3267 vol_args->name);
3268 }
3269 out:
3270 kfree(vol_args);
3271 err_drop:
3272 mnt_drop_write_file(file);
3273 if (bdev)
3274 blkdev_put(bdev, mode);
3275 return ret;
3276 }
3277
3278 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
3279 {
3280 struct inode *inode = file_inode(file);
3281 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3282 struct btrfs_ioctl_vol_args *vol_args;
3283 struct block_device *bdev = NULL;
3284 fmode_t mode;
3285 int ret;
3286 bool cancel;
3287
3288 if (!capable(CAP_SYS_ADMIN))
3289 return -EPERM;
3290
3291 ret = mnt_want_write_file(file);
3292 if (ret)
3293 return ret;
3294
3295 vol_args = memdup_user(arg, sizeof(*vol_args));
3296 if (IS_ERR(vol_args)) {
3297 ret = PTR_ERR(vol_args);
3298 goto out_drop_write;
3299 }
3300 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3301 cancel = (strcmp("cancel", vol_args->name) == 0);
3302
3303 ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,
3304 cancel);
3305 if (ret == 0) {
3306 ret = btrfs_rm_device(fs_info, vol_args->name, 0, &bdev, &mode);
3307 if (!ret)
3308 btrfs_info(fs_info, "disk deleted %s", vol_args->name);
3309 btrfs_exclop_finish(fs_info);
3310 }
3311
3312 kfree(vol_args);
3313 out_drop_write:
3314 mnt_drop_write_file(file);
3315 if (bdev)
3316 blkdev_put(bdev, mode);
3317 return ret;
3318 }
3319
3320 static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,
3321 void __user *arg)
3322 {
3323 struct btrfs_ioctl_fs_info_args *fi_args;
3324 struct btrfs_device *device;
3325 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
3326 u64 flags_in;
3327 int ret = 0;
3328
3329 fi_args = memdup_user(arg, sizeof(*fi_args));
3330 if (IS_ERR(fi_args))
3331 return PTR_ERR(fi_args);
3332
3333 flags_in = fi_args->flags;
3334 memset(fi_args, 0, sizeof(*fi_args));
3335
3336 rcu_read_lock();
3337 fi_args->num_devices = fs_devices->num_devices;
3338
3339 list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
3340 if (device->devid > fi_args->max_id)
3341 fi_args->max_id = device->devid;
3342 }
3343 rcu_read_unlock();
3344
3345 memcpy(&fi_args->fsid, fs_devices->fsid, sizeof(fi_args->fsid));
3346 fi_args->nodesize = fs_info->nodesize;
3347 fi_args->sectorsize = fs_info->sectorsize;
3348 fi_args->clone_alignment = fs_info->sectorsize;
3349
3350 if (flags_in & BTRFS_FS_INFO_FLAG_CSUM_INFO) {
3351 fi_args->csum_type = btrfs_super_csum_type(fs_info->super_copy);
3352 fi_args->csum_size = btrfs_super_csum_size(fs_info->super_copy);
3353 fi_args->flags |= BTRFS_FS_INFO_FLAG_CSUM_INFO;
3354 }
3355
3356 if (flags_in & BTRFS_FS_INFO_FLAG_GENERATION) {
3357 fi_args->generation = fs_info->generation;
3358 fi_args->flags |= BTRFS_FS_INFO_FLAG_GENERATION;
3359 }
3360
3361 if (flags_in & BTRFS_FS_INFO_FLAG_METADATA_UUID) {
3362 memcpy(&fi_args->metadata_uuid, fs_devices->metadata_uuid,
3363 sizeof(fi_args->metadata_uuid));
3364 fi_args->flags |= BTRFS_FS_INFO_FLAG_METADATA_UUID;
3365 }
3366
3367 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
3368 ret = -EFAULT;
3369
3370 kfree(fi_args);
3371 return ret;
3372 }
3373
3374 static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,
3375 void __user *arg)
3376 {
3377 struct btrfs_ioctl_dev_info_args *di_args;
3378 struct btrfs_device *dev;
3379 int ret = 0;
3380 char *s_uuid = NULL;
3381
3382 di_args = memdup_user(arg, sizeof(*di_args));
3383 if (IS_ERR(di_args))
3384 return PTR_ERR(di_args);
3385
3386 if (!btrfs_is_empty_uuid(di_args->uuid))
3387 s_uuid = di_args->uuid;
3388
3389 rcu_read_lock();
3390 dev = btrfs_find_device(fs_info->fs_devices, di_args->devid, s_uuid,
3391 NULL);
3392
3393 if (!dev) {
3394 ret = -ENODEV;
3395 goto out;
3396 }
3397
3398 di_args->devid = dev->devid;
3399 di_args->bytes_used = btrfs_device_get_bytes_used(dev);
3400 di_args->total_bytes = btrfs_device_get_total_bytes(dev);
3401 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
3402 if (dev->name) {
3403 strncpy(di_args->path, rcu_str_deref(dev->name),
3404 sizeof(di_args->path) - 1);
3405 di_args->path[sizeof(di_args->path) - 1] = 0;
3406 } else {
3407 di_args->path[0] = '\0';
3408 }
3409
3410 out:
3411 rcu_read_unlock();
3412 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
3413 ret = -EFAULT;
3414
3415 kfree(di_args);
3416 return ret;
3417 }
3418
3419 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3420 {
3421 struct inode *inode = file_inode(file);
3422 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3423 struct btrfs_root *root = BTRFS_I(inode)->root;
3424 struct btrfs_root *new_root;
3425 struct btrfs_dir_item *di;
3426 struct btrfs_trans_handle *trans;
3427 struct btrfs_path *path = NULL;
3428 struct btrfs_disk_key disk_key;
3429 u64 objectid = 0;
3430 u64 dir_id;
3431 int ret;
3432
3433 if (!capable(CAP_SYS_ADMIN))
3434 return -EPERM;
3435
3436 ret = mnt_want_write_file(file);
3437 if (ret)
3438 return ret;
3439
3440 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3441 ret = -EFAULT;
3442 goto out;
3443 }
3444
3445 if (!objectid)
3446 objectid = BTRFS_FS_TREE_OBJECTID;
3447
3448 new_root = btrfs_get_fs_root(fs_info, objectid, true);
3449 if (IS_ERR(new_root)) {
3450 ret = PTR_ERR(new_root);
3451 goto out;
3452 }
3453 if (!is_fstree(new_root->root_key.objectid)) {
3454 ret = -ENOENT;
3455 goto out_free;
3456 }
3457
3458 path = btrfs_alloc_path();
3459 if (!path) {
3460 ret = -ENOMEM;
3461 goto out_free;
3462 }
3463
3464 trans = btrfs_start_transaction(root, 1);
3465 if (IS_ERR(trans)) {
3466 ret = PTR_ERR(trans);
3467 goto out_free;
3468 }
3469
3470 dir_id = btrfs_super_root_dir(fs_info->super_copy);
3471 di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
3472 dir_id, "default", 7, 1);
3473 if (IS_ERR_OR_NULL(di)) {
3474 btrfs_release_path(path);
3475 btrfs_end_transaction(trans);
3476 btrfs_err(fs_info,
3477 "Umm, you don't have the default diritem, this isn't going to work");
3478 ret = -ENOENT;
3479 goto out_free;
3480 }
3481
3482 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3483 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3484 btrfs_mark_buffer_dirty(path->nodes[0]);
3485 btrfs_release_path(path);
3486
3487 btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
3488 btrfs_end_transaction(trans);
3489 out_free:
3490 btrfs_put_root(new_root);
3491 btrfs_free_path(path);
3492 out:
3493 mnt_drop_write_file(file);
3494 return ret;
3495 }
3496
3497 static void get_block_group_info(struct list_head *groups_list,
3498 struct btrfs_ioctl_space_info *space)
3499 {
3500 struct btrfs_block_group *block_group;
3501
3502 space->total_bytes = 0;
3503 space->used_bytes = 0;
3504 space->flags = 0;
3505 list_for_each_entry(block_group, groups_list, list) {
3506 space->flags = block_group->flags;
3507 space->total_bytes += block_group->length;
3508 space->used_bytes += block_group->used;
3509 }
3510 }
3511
3512 static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
3513 void __user *arg)
3514 {
3515 struct btrfs_ioctl_space_args space_args;
3516 struct btrfs_ioctl_space_info space;
3517 struct btrfs_ioctl_space_info *dest;
3518 struct btrfs_ioctl_space_info *dest_orig;
3519 struct btrfs_ioctl_space_info __user *user_dest;
3520 struct btrfs_space_info *info;
3521 static const u64 types[] = {
3522 BTRFS_BLOCK_GROUP_DATA,
3523 BTRFS_BLOCK_GROUP_SYSTEM,
3524 BTRFS_BLOCK_GROUP_METADATA,
3525 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA
3526 };
3527 int num_types = 4;
3528 int alloc_size;
3529 int ret = 0;
3530 u64 slot_count = 0;
3531 int i, c;
3532
3533 if (copy_from_user(&space_args,
3534 (struct btrfs_ioctl_space_args __user *)arg,
3535 sizeof(space_args)))
3536 return -EFAULT;
3537
3538 for (i = 0; i < num_types; i++) {
3539 struct btrfs_space_info *tmp;
3540
3541 info = NULL;
3542 list_for_each_entry(tmp, &fs_info->space_info, list) {
3543 if (tmp->flags == types[i]) {
3544 info = tmp;
3545 break;
3546 }
3547 }
3548
3549 if (!info)
3550 continue;
3551
3552 down_read(&info->groups_sem);
3553 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3554 if (!list_empty(&info->block_groups[c]))
3555 slot_count++;
3556 }
3557 up_read(&info->groups_sem);
3558 }
3559
3560 /*
3561 * Global block reserve, exported as a space_info
3562 */
3563 slot_count++;
3564
3565 /* space_slots == 0 means they are asking for a count */
3566 if (space_args.space_slots == 0) {
3567 space_args.total_spaces = slot_count;
3568 goto out;
3569 }
3570
3571 slot_count = min_t(u64, space_args.space_slots, slot_count);
3572
3573 alloc_size = sizeof(*dest) * slot_count;
3574
3575 /* we generally have at most 6 or so space infos, one for each raid
3576 * level. So, a whole page should be more than enough for everyone
3577 */
3578 if (alloc_size > PAGE_SIZE)
3579 return -ENOMEM;
3580
3581 space_args.total_spaces = 0;
3582 dest = kmalloc(alloc_size, GFP_KERNEL);
3583 if (!dest)
3584 return -ENOMEM;
3585 dest_orig = dest;
3586
3587 /* now we have a buffer to copy into */
3588 for (i = 0; i < num_types; i++) {
3589 struct btrfs_space_info *tmp;
3590
3591 if (!slot_count)
3592 break;
3593
3594 info = NULL;
3595 list_for_each_entry(tmp, &fs_info->space_info, list) {
3596 if (tmp->flags == types[i]) {
3597 info = tmp;
3598 break;
3599 }
3600 }
3601
3602 if (!info)
3603 continue;
3604 down_read(&info->groups_sem);
3605 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3606 if (!list_empty(&info->block_groups[c])) {
3607 get_block_group_info(&info->block_groups[c],
3608 &space);
3609 memcpy(dest, &space, sizeof(space));
3610 dest++;
3611 space_args.total_spaces++;
3612 slot_count--;
3613 }
3614 if (!slot_count)
3615 break;
3616 }
3617 up_read(&info->groups_sem);
3618 }
3619
3620 /*
3621 * Add global block reserve
3622 */
3623 if (slot_count) {
3624 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3625
3626 spin_lock(&block_rsv->lock);
3627 space.total_bytes = block_rsv->size;
3628 space.used_bytes = block_rsv->size - block_rsv->reserved;
3629 spin_unlock(&block_rsv->lock);
3630 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
3631 memcpy(dest, &space, sizeof(space));
3632 space_args.total_spaces++;
3633 }
3634
3635 user_dest = (struct btrfs_ioctl_space_info __user *)
3636 (arg + sizeof(struct btrfs_ioctl_space_args));
3637
3638 if (copy_to_user(user_dest, dest_orig, alloc_size))
3639 ret = -EFAULT;
3640
3641 kfree(dest_orig);
3642 out:
3643 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
3644 ret = -EFAULT;
3645
3646 return ret;
3647 }
3648
3649 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
3650 void __user *argp)
3651 {
3652 struct btrfs_trans_handle *trans;
3653 u64 transid;
3654 int ret;
3655
3656 trans = btrfs_attach_transaction_barrier(root);
3657 if (IS_ERR(trans)) {
3658 if (PTR_ERR(trans) != -ENOENT)
3659 return PTR_ERR(trans);
3660
3661 /* No running transaction, don't bother */
3662 transid = root->fs_info->last_trans_committed;
3663 goto out;
3664 }
3665 transid = trans->transid;
3666 ret = btrfs_commit_transaction_async(trans);
3667 if (ret) {
3668 btrfs_end_transaction(trans);
3669 return ret;
3670 }
3671 out:
3672 if (argp)
3673 if (copy_to_user(argp, &transid, sizeof(transid)))
3674 return -EFAULT;
3675 return 0;
3676 }
3677
3678 static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,
3679 void __user *argp)
3680 {
3681 u64 transid;
3682
3683 if (argp) {
3684 if (copy_from_user(&transid, argp, sizeof(transid)))
3685 return -EFAULT;
3686 } else {
3687 transid = 0; /* current trans */
3688 }
3689 return btrfs_wait_for_commit(fs_info, transid);
3690 }
3691
3692 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
3693 {
3694 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
3695 struct btrfs_ioctl_scrub_args *sa;
3696 int ret;
3697
3698 if (!capable(CAP_SYS_ADMIN))
3699 return -EPERM;
3700
3701 sa = memdup_user(arg, sizeof(*sa));
3702 if (IS_ERR(sa))
3703 return PTR_ERR(sa);
3704
3705 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
3706 ret = mnt_want_write_file(file);
3707 if (ret)
3708 goto out;
3709 }
3710
3711 ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,
3712 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
3713 0);
3714
3715 /*
3716 * Copy scrub args to user space even if btrfs_scrub_dev() returned an
3717 * error. This is important as it allows user space to know how much
3718 * progress scrub has done. For example, if scrub is canceled we get
3719 * -ECANCELED from btrfs_scrub_dev() and return that error back to user
3720 * space. Later user space can inspect the progress from the structure
3721 * btrfs_ioctl_scrub_args and resume scrub from where it left off
3722 * previously (btrfs-progs does this).
3723 * If we fail to copy the btrfs_ioctl_scrub_args structure to user space
3724 * then return -EFAULT to signal the structure was not copied or it may
3725 * be corrupt and unreliable due to a partial copy.
3726 */
3727 if (copy_to_user(arg, sa, sizeof(*sa)))
3728 ret = -EFAULT;
3729
3730 if (!(sa->flags & BTRFS_SCRUB_READONLY))
3731 mnt_drop_write_file(file);
3732 out:
3733 kfree(sa);
3734 return ret;
3735 }
3736
3737 static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)
3738 {
3739 if (!capable(CAP_SYS_ADMIN))
3740 return -EPERM;
3741
3742 return btrfs_scrub_cancel(fs_info);
3743 }
3744
3745 static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
3746 void __user *arg)
3747 {
3748 struct btrfs_ioctl_scrub_args *sa;
3749 int ret;
3750
3751 if (!capable(CAP_SYS_ADMIN))
3752 return -EPERM;
3753
3754 sa = memdup_user(arg, sizeof(*sa));
3755 if (IS_ERR(sa))
3756 return PTR_ERR(sa);
3757
3758 ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
3759
3760 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
3761 ret = -EFAULT;
3762
3763 kfree(sa);
3764 return ret;
3765 }
3766
3767 static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
3768 void __user *arg)
3769 {
3770 struct btrfs_ioctl_get_dev_stats *sa;
3771 int ret;
3772
3773 sa = memdup_user(arg, sizeof(*sa));
3774 if (IS_ERR(sa))
3775 return PTR_ERR(sa);
3776
3777 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3778 kfree(sa);
3779 return -EPERM;
3780 }
3781
3782 ret = btrfs_get_dev_stats(fs_info, sa);
3783
3784 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
3785 ret = -EFAULT;
3786
3787 kfree(sa);
3788 return ret;
3789 }
3790
3791 static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
3792 void __user *arg)
3793 {
3794 struct btrfs_ioctl_dev_replace_args *p;
3795 int ret;
3796
3797 if (!capable(CAP_SYS_ADMIN))
3798 return -EPERM;
3799
3800 p = memdup_user(arg, sizeof(*p));
3801 if (IS_ERR(p))
3802 return PTR_ERR(p);
3803
3804 switch (p->cmd) {
3805 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3806 if (sb_rdonly(fs_info->sb)) {
3807 ret = -EROFS;
3808 goto out;
3809 }
3810 if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_REPLACE)) {
3811 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3812 } else {
3813 ret = btrfs_dev_replace_by_ioctl(fs_info, p);
3814 btrfs_exclop_finish(fs_info);
3815 }
3816 break;
3817 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
3818 btrfs_dev_replace_status(fs_info, p);
3819 ret = 0;
3820 break;
3821 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
3822 p->result = btrfs_dev_replace_cancel(fs_info);
3823 ret = 0;
3824 break;
3825 default:
3826 ret = -EINVAL;
3827 break;
3828 }
3829
3830 if ((ret == 0 || ret == -ECANCELED) && copy_to_user(arg, p, sizeof(*p)))
3831 ret = -EFAULT;
3832 out:
3833 kfree(p);
3834 return ret;
3835 }
3836
3837 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3838 {
3839 int ret = 0;
3840 int i;
3841 u64 rel_ptr;
3842 int size;
3843 struct btrfs_ioctl_ino_path_args *ipa = NULL;
3844 struct inode_fs_paths *ipath = NULL;
3845 struct btrfs_path *path;
3846
3847 if (!capable(CAP_DAC_READ_SEARCH))
3848 return -EPERM;
3849
3850 path = btrfs_alloc_path();
3851 if (!path) {
3852 ret = -ENOMEM;
3853 goto out;
3854 }
3855
3856 ipa = memdup_user(arg, sizeof(*ipa));
3857 if (IS_ERR(ipa)) {
3858 ret = PTR_ERR(ipa);
3859 ipa = NULL;
3860 goto out;
3861 }
3862
3863 size = min_t(u32, ipa->size, 4096);
3864 ipath = init_ipath(size, root, path);
3865 if (IS_ERR(ipath)) {
3866 ret = PTR_ERR(ipath);
3867 ipath = NULL;
3868 goto out;
3869 }
3870
3871 ret = paths_from_inode(ipa->inum, ipath);
3872 if (ret < 0)
3873 goto out;
3874
3875 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3876 rel_ptr = ipath->fspath->val[i] -
3877 (u64)(unsigned long)ipath->fspath->val;
3878 ipath->fspath->val[i] = rel_ptr;
3879 }
3880
3881 ret = copy_to_user((void __user *)(unsigned long)ipa->fspath,
3882 ipath->fspath, size);
3883 if (ret) {
3884 ret = -EFAULT;
3885 goto out;
3886 }
3887
3888 out:
3889 btrfs_free_path(path);
3890 free_ipath(ipath);
3891 kfree(ipa);
3892
3893 return ret;
3894 }
3895
3896 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3897 {
3898 struct btrfs_data_container *inodes = ctx;
3899 const size_t c = 3 * sizeof(u64);
3900
3901 if (inodes->bytes_left >= c) {
3902 inodes->bytes_left -= c;
3903 inodes->val[inodes->elem_cnt] = inum;
3904 inodes->val[inodes->elem_cnt + 1] = offset;
3905 inodes->val[inodes->elem_cnt + 2] = root;
3906 inodes->elem_cnt += 3;
3907 } else {
3908 inodes->bytes_missing += c - inodes->bytes_left;
3909 inodes->bytes_left = 0;
3910 inodes->elem_missed += 3;
3911 }
3912
3913 return 0;
3914 }
3915
3916 static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,
3917 void __user *arg, int version)
3918 {
3919 int ret = 0;
3920 int size;
3921 struct btrfs_ioctl_logical_ino_args *loi;
3922 struct btrfs_data_container *inodes = NULL;
3923 struct btrfs_path *path = NULL;
3924 bool ignore_offset;
3925
3926 if (!capable(CAP_SYS_ADMIN))
3927 return -EPERM;
3928
3929 loi = memdup_user(arg, sizeof(*loi));
3930 if (IS_ERR(loi))
3931 return PTR_ERR(loi);
3932
3933 if (version == 1) {
3934 ignore_offset = false;
3935 size = min_t(u32, loi->size, SZ_64K);
3936 } else {
3937 /* All reserved bits must be 0 for now */
3938 if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) {
3939 ret = -EINVAL;
3940 goto out_loi;
3941 }
3942 /* Only accept flags we have defined so far */
3943 if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) {
3944 ret = -EINVAL;
3945 goto out_loi;
3946 }
3947 ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET;
3948 size = min_t(u32, loi->size, SZ_16M);
3949 }
3950
3951 path = btrfs_alloc_path();
3952 if (!path) {
3953 ret = -ENOMEM;
3954 goto out;
3955 }
3956
3957 inodes = init_data_container(size);
3958 if (IS_ERR(inodes)) {
3959 ret = PTR_ERR(inodes);
3960 inodes = NULL;
3961 goto out;
3962 }
3963
3964 ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
3965 build_ino_list, inodes, ignore_offset);
3966 if (ret == -EINVAL)
3967 ret = -ENOENT;
3968 if (ret < 0)
3969 goto out;
3970
3971 ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes,
3972 size);
3973 if (ret)
3974 ret = -EFAULT;
3975
3976 out:
3977 btrfs_free_path(path);
3978 kvfree(inodes);
3979 out_loi:
3980 kfree(loi);
3981
3982 return ret;
3983 }
3984
3985 void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info,
3986 struct btrfs_ioctl_balance_args *bargs)
3987 {
3988 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3989
3990 bargs->flags = bctl->flags;
3991
3992 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags))
3993 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3994 if (atomic_read(&fs_info->balance_pause_req))
3995 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3996 if (atomic_read(&fs_info->balance_cancel_req))
3997 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3998
3999 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4000 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4001 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4002
4003 spin_lock(&fs_info->balance_lock);
4004 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4005 spin_unlock(&fs_info->balance_lock);
4006 }
4007
4008 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4009 {
4010 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4011 struct btrfs_fs_info *fs_info = root->fs_info;
4012 struct btrfs_ioctl_balance_args *bargs;
4013 struct btrfs_balance_control *bctl;
4014 bool need_unlock; /* for mut. excl. ops lock */
4015 int ret;
4016
4017 if (!capable(CAP_SYS_ADMIN))
4018 return -EPERM;
4019
4020 ret = mnt_want_write_file(file);
4021 if (ret)
4022 return ret;
4023
4024 again:
4025 if (btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) {
4026 mutex_lock(&fs_info->balance_mutex);
4027 need_unlock = true;
4028 goto locked;
4029 }
4030
4031 /*
4032 * mut. excl. ops lock is locked. Three possibilities:
4033 * (1) some other op is running
4034 * (2) balance is running
4035 * (3) balance is paused -- special case (think resume)
4036 */
4037 mutex_lock(&fs_info->balance_mutex);
4038 if (fs_info->balance_ctl) {
4039 /* this is either (2) or (3) */
4040 if (!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4041 mutex_unlock(&fs_info->balance_mutex);
4042 /*
4043 * Lock released to allow other waiters to continue,
4044 * we'll reexamine the status again.
4045 */
4046 mutex_lock(&fs_info->balance_mutex);
4047
4048 if (fs_info->balance_ctl &&
4049 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4050 /* this is (3) */
4051 need_unlock = false;
4052 goto locked;
4053 }
4054
4055 mutex_unlock(&fs_info->balance_mutex);
4056 goto again;
4057 } else {
4058 /* this is (2) */
4059 mutex_unlock(&fs_info->balance_mutex);
4060 ret = -EINPROGRESS;
4061 goto out;
4062 }
4063 } else {
4064 /* this is (1) */
4065 mutex_unlock(&fs_info->balance_mutex);
4066 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4067 goto out;
4068 }
4069
4070 locked:
4071
4072 if (arg) {
4073 bargs = memdup_user(arg, sizeof(*bargs));
4074 if (IS_ERR(bargs)) {
4075 ret = PTR_ERR(bargs);
4076 goto out_unlock;
4077 }
4078
4079 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4080 if (!fs_info->balance_ctl) {
4081 ret = -ENOTCONN;
4082 goto out_bargs;
4083 }
4084
4085 bctl = fs_info->balance_ctl;
4086 spin_lock(&fs_info->balance_lock);
4087 bctl->flags |= BTRFS_BALANCE_RESUME;
4088 spin_unlock(&fs_info->balance_lock);
4089
4090 goto do_balance;
4091 }
4092 } else {
4093 bargs = NULL;
4094 }
4095
4096 if (fs_info->balance_ctl) {
4097 ret = -EINPROGRESS;
4098 goto out_bargs;
4099 }
4100
4101 bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
4102 if (!bctl) {
4103 ret = -ENOMEM;
4104 goto out_bargs;
4105 }
4106
4107 if (arg) {
4108 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4109 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4110 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4111
4112 bctl->flags = bargs->flags;
4113 } else {
4114 /* balance everything - no filters */
4115 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4116 }
4117
4118 if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
4119 ret = -EINVAL;
4120 goto out_bctl;
4121 }
4122
4123 do_balance:
4124 /*
4125 * Ownership of bctl and exclusive operation goes to btrfs_balance.
4126 * bctl is freed in reset_balance_state, or, if restriper was paused
4127 * all the way until unmount, in free_fs_info. The flag should be
4128 * cleared after reset_balance_state.
4129 */
4130 need_unlock = false;
4131
4132 ret = btrfs_balance(fs_info, bctl, bargs);
4133 bctl = NULL;
4134
4135 if ((ret == 0 || ret == -ECANCELED) && arg) {
4136 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4137 ret = -EFAULT;
4138 }
4139
4140 out_bctl:
4141 kfree(bctl);
4142 out_bargs:
4143 kfree(bargs);
4144 out_unlock:
4145 mutex_unlock(&fs_info->balance_mutex);
4146 if (need_unlock)
4147 btrfs_exclop_finish(fs_info);
4148 out:
4149 mnt_drop_write_file(file);
4150 return ret;
4151 }
4152
4153 static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
4154 {
4155 if (!capable(CAP_SYS_ADMIN))
4156 return -EPERM;
4157
4158 switch (cmd) {
4159 case BTRFS_BALANCE_CTL_PAUSE:
4160 return btrfs_pause_balance(fs_info);
4161 case BTRFS_BALANCE_CTL_CANCEL:
4162 return btrfs_cancel_balance(fs_info);
4163 }
4164
4165 return -EINVAL;
4166 }
4167
4168 static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
4169 void __user *arg)
4170 {
4171 struct btrfs_ioctl_balance_args *bargs;
4172 int ret = 0;
4173
4174 if (!capable(CAP_SYS_ADMIN))
4175 return -EPERM;
4176
4177 mutex_lock(&fs_info->balance_mutex);
4178 if (!fs_info->balance_ctl) {
4179 ret = -ENOTCONN;
4180 goto out;
4181 }
4182
4183 bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
4184 if (!bargs) {
4185 ret = -ENOMEM;
4186 goto out;
4187 }
4188
4189 btrfs_update_ioctl_balance_args(fs_info, bargs);
4190
4191 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4192 ret = -EFAULT;
4193
4194 kfree(bargs);
4195 out:
4196 mutex_unlock(&fs_info->balance_mutex);
4197 return ret;
4198 }
4199
4200 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4201 {
4202 struct inode *inode = file_inode(file);
4203 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4204 struct btrfs_ioctl_quota_ctl_args *sa;
4205 int ret;
4206
4207 if (!capable(CAP_SYS_ADMIN))
4208 return -EPERM;
4209
4210 ret = mnt_want_write_file(file);
4211 if (ret)
4212 return ret;
4213
4214 sa = memdup_user(arg, sizeof(*sa));
4215 if (IS_ERR(sa)) {
4216 ret = PTR_ERR(sa);
4217 goto drop_write;
4218 }
4219
4220 down_write(&fs_info->subvol_sem);
4221
4222 switch (sa->cmd) {
4223 case BTRFS_QUOTA_CTL_ENABLE:
4224 ret = btrfs_quota_enable(fs_info);
4225 break;
4226 case BTRFS_QUOTA_CTL_DISABLE:
4227 ret = btrfs_quota_disable(fs_info);
4228 break;
4229 default:
4230 ret = -EINVAL;
4231 break;
4232 }
4233
4234 kfree(sa);
4235 up_write(&fs_info->subvol_sem);
4236 drop_write:
4237 mnt_drop_write_file(file);
4238 return ret;
4239 }
4240
4241 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4242 {
4243 struct inode *inode = file_inode(file);
4244 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4245 struct btrfs_root *root = BTRFS_I(inode)->root;
4246 struct btrfs_ioctl_qgroup_assign_args *sa;
4247 struct btrfs_trans_handle *trans;
4248 int ret;
4249 int err;
4250
4251 if (!capable(CAP_SYS_ADMIN))
4252 return -EPERM;
4253
4254 ret = mnt_want_write_file(file);
4255 if (ret)
4256 return ret;
4257
4258 sa = memdup_user(arg, sizeof(*sa));
4259 if (IS_ERR(sa)) {
4260 ret = PTR_ERR(sa);
4261 goto drop_write;
4262 }
4263
4264 trans = btrfs_join_transaction(root);
4265 if (IS_ERR(trans)) {
4266 ret = PTR_ERR(trans);
4267 goto out;
4268 }
4269
4270 if (sa->assign) {
4271 ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst);
4272 } else {
4273 ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst);
4274 }
4275
4276 /* update qgroup status and info */
4277 err = btrfs_run_qgroups(trans);
4278 if (err < 0)
4279 btrfs_handle_fs_error(fs_info, err,
4280 "failed to update qgroup status and info");
4281 err = btrfs_end_transaction(trans);
4282 if (err && !ret)
4283 ret = err;
4284
4285 out:
4286 kfree(sa);
4287 drop_write:
4288 mnt_drop_write_file(file);
4289 return ret;
4290 }
4291
4292 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4293 {
4294 struct inode *inode = file_inode(file);
4295 struct btrfs_root *root = BTRFS_I(inode)->root;
4296 struct btrfs_ioctl_qgroup_create_args *sa;
4297 struct btrfs_trans_handle *trans;
4298 int ret;
4299 int err;
4300
4301 if (!capable(CAP_SYS_ADMIN))
4302 return -EPERM;
4303
4304 ret = mnt_want_write_file(file);
4305 if (ret)
4306 return ret;
4307
4308 sa = memdup_user(arg, sizeof(*sa));
4309 if (IS_ERR(sa)) {
4310 ret = PTR_ERR(sa);
4311 goto drop_write;
4312 }
4313
4314 if (!sa->qgroupid) {
4315 ret = -EINVAL;
4316 goto out;
4317 }
4318
4319 trans = btrfs_join_transaction(root);
4320 if (IS_ERR(trans)) {
4321 ret = PTR_ERR(trans);
4322 goto out;
4323 }
4324
4325 if (sa->create) {
4326 ret = btrfs_create_qgroup(trans, sa->qgroupid);
4327 } else {
4328 ret = btrfs_remove_qgroup(trans, sa->qgroupid);
4329 }
4330
4331 err = btrfs_end_transaction(trans);
4332 if (err && !ret)
4333 ret = err;
4334
4335 out:
4336 kfree(sa);
4337 drop_write:
4338 mnt_drop_write_file(file);
4339 return ret;
4340 }
4341
4342 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4343 {
4344 struct inode *inode = file_inode(file);
4345 struct btrfs_root *root = BTRFS_I(inode)->root;
4346 struct btrfs_ioctl_qgroup_limit_args *sa;
4347 struct btrfs_trans_handle *trans;
4348 int ret;
4349 int err;
4350 u64 qgroupid;
4351
4352 if (!capable(CAP_SYS_ADMIN))
4353 return -EPERM;
4354
4355 ret = mnt_want_write_file(file);
4356 if (ret)
4357 return ret;
4358
4359 sa = memdup_user(arg, sizeof(*sa));
4360 if (IS_ERR(sa)) {
4361 ret = PTR_ERR(sa);
4362 goto drop_write;
4363 }
4364
4365 trans = btrfs_join_transaction(root);
4366 if (IS_ERR(trans)) {
4367 ret = PTR_ERR(trans);
4368 goto out;
4369 }
4370
4371 qgroupid = sa->qgroupid;
4372 if (!qgroupid) {
4373 /* take the current subvol as qgroup */
4374 qgroupid = root->root_key.objectid;
4375 }
4376
4377 ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim);
4378
4379 err = btrfs_end_transaction(trans);
4380 if (err && !ret)
4381 ret = err;
4382
4383 out:
4384 kfree(sa);
4385 drop_write:
4386 mnt_drop_write_file(file);
4387 return ret;
4388 }
4389
4390 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4391 {
4392 struct inode *inode = file_inode(file);
4393 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4394 struct btrfs_ioctl_quota_rescan_args *qsa;
4395 int ret;
4396
4397 if (!capable(CAP_SYS_ADMIN))
4398 return -EPERM;
4399
4400 ret = mnt_want_write_file(file);
4401 if (ret)
4402 return ret;
4403
4404 qsa = memdup_user(arg, sizeof(*qsa));
4405 if (IS_ERR(qsa)) {
4406 ret = PTR_ERR(qsa);
4407 goto drop_write;
4408 }
4409
4410 if (qsa->flags) {
4411 ret = -EINVAL;
4412 goto out;
4413 }
4414
4415 ret = btrfs_qgroup_rescan(fs_info);
4416
4417 out:
4418 kfree(qsa);
4419 drop_write:
4420 mnt_drop_write_file(file);
4421 return ret;
4422 }
4423
4424 static long btrfs_ioctl_quota_rescan_status(struct btrfs_fs_info *fs_info,
4425 void __user *arg)
4426 {
4427 struct btrfs_ioctl_quota_rescan_args qsa = {0};
4428 int ret = 0;
4429
4430 if (!capable(CAP_SYS_ADMIN))
4431 return -EPERM;
4432
4433 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4434 qsa.flags = 1;
4435 qsa.progress = fs_info->qgroup_rescan_progress.objectid;
4436 }
4437
4438 if (copy_to_user(arg, &qsa, sizeof(qsa)))
4439 ret = -EFAULT;
4440
4441 return ret;
4442 }
4443
4444 static long btrfs_ioctl_quota_rescan_wait(struct btrfs_fs_info *fs_info,
4445 void __user *arg)
4446 {
4447 if (!capable(CAP_SYS_ADMIN))
4448 return -EPERM;
4449
4450 return btrfs_qgroup_wait_for_completion(fs_info, true);
4451 }
4452
4453 static long _btrfs_ioctl_set_received_subvol(struct file *file,
4454 struct user_namespace *mnt_userns,
4455 struct btrfs_ioctl_received_subvol_args *sa)
4456 {
4457 struct inode *inode = file_inode(file);
4458 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4459 struct btrfs_root *root = BTRFS_I(inode)->root;
4460 struct btrfs_root_item *root_item = &root->root_item;
4461 struct btrfs_trans_handle *trans;
4462 struct timespec64 ct = current_time(inode);
4463 int ret = 0;
4464 int received_uuid_changed;
4465
4466 if (!inode_owner_or_capable(mnt_userns, inode))
4467 return -EPERM;
4468
4469 ret = mnt_want_write_file(file);
4470 if (ret < 0)
4471 return ret;
4472
4473 down_write(&fs_info->subvol_sem);
4474
4475 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
4476 ret = -EINVAL;
4477 goto out;
4478 }
4479
4480 if (btrfs_root_readonly(root)) {
4481 ret = -EROFS;
4482 goto out;
4483 }
4484
4485 /*
4486 * 1 - root item
4487 * 2 - uuid items (received uuid + subvol uuid)
4488 */
4489 trans = btrfs_start_transaction(root, 3);
4490 if (IS_ERR(trans)) {
4491 ret = PTR_ERR(trans);
4492 trans = NULL;
4493 goto out;
4494 }
4495
4496 sa->rtransid = trans->transid;
4497 sa->rtime.sec = ct.tv_sec;
4498 sa->rtime.nsec = ct.tv_nsec;
4499
4500 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4501 BTRFS_UUID_SIZE);
4502 if (received_uuid_changed &&
4503 !btrfs_is_empty_uuid(root_item->received_uuid)) {
4504 ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid,
4505 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4506 root->root_key.objectid);
4507 if (ret && ret != -ENOENT) {
4508 btrfs_abort_transaction(trans, ret);
4509 btrfs_end_transaction(trans);
4510 goto out;
4511 }
4512 }
4513 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4514 btrfs_set_root_stransid(root_item, sa->stransid);
4515 btrfs_set_root_rtransid(root_item, sa->rtransid);
4516 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4517 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4518 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4519 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4520
4521 ret = btrfs_update_root(trans, fs_info->tree_root,
4522 &root->root_key, &root->root_item);
4523 if (ret < 0) {
4524 btrfs_end_transaction(trans);
4525 goto out;
4526 }
4527 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4528 ret = btrfs_uuid_tree_add(trans, sa->uuid,
4529 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4530 root->root_key.objectid);
4531 if (ret < 0 && ret != -EEXIST) {
4532 btrfs_abort_transaction(trans, ret);
4533 btrfs_end_transaction(trans);
4534 goto out;
4535 }
4536 }
4537 ret = btrfs_commit_transaction(trans);
4538 out:
4539 up_write(&fs_info->subvol_sem);
4540 mnt_drop_write_file(file);
4541 return ret;
4542 }
4543
4544 #ifdef CONFIG_64BIT
4545 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4546 void __user *arg)
4547 {
4548 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4549 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4550 int ret = 0;
4551
4552 args32 = memdup_user(arg, sizeof(*args32));
4553 if (IS_ERR(args32))
4554 return PTR_ERR(args32);
4555
4556 args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
4557 if (!args64) {
4558 ret = -ENOMEM;
4559 goto out;
4560 }
4561
4562 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4563 args64->stransid = args32->stransid;
4564 args64->rtransid = args32->rtransid;
4565 args64->stime.sec = args32->stime.sec;
4566 args64->stime.nsec = args32->stime.nsec;
4567 args64->rtime.sec = args32->rtime.sec;
4568 args64->rtime.nsec = args32->rtime.nsec;
4569 args64->flags = args32->flags;
4570
4571 ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_user_ns(file), args64);
4572 if (ret)
4573 goto out;
4574
4575 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4576 args32->stransid = args64->stransid;
4577 args32->rtransid = args64->rtransid;
4578 args32->stime.sec = args64->stime.sec;
4579 args32->stime.nsec = args64->stime.nsec;
4580 args32->rtime.sec = args64->rtime.sec;
4581 args32->rtime.nsec = args64->rtime.nsec;
4582 args32->flags = args64->flags;
4583
4584 ret = copy_to_user(arg, args32, sizeof(*args32));
4585 if (ret)
4586 ret = -EFAULT;
4587
4588 out:
4589 kfree(args32);
4590 kfree(args64);
4591 return ret;
4592 }
4593 #endif
4594
4595 static long btrfs_ioctl_set_received_subvol(struct file *file,
4596 void __user *arg)
4597 {
4598 struct btrfs_ioctl_received_subvol_args *sa = NULL;
4599 int ret = 0;
4600
4601 sa = memdup_user(arg, sizeof(*sa));
4602 if (IS_ERR(sa))
4603 return PTR_ERR(sa);
4604
4605 ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_user_ns(file), sa);
4606
4607 if (ret)
4608 goto out;
4609
4610 ret = copy_to_user(arg, sa, sizeof(*sa));
4611 if (ret)
4612 ret = -EFAULT;
4613
4614 out:
4615 kfree(sa);
4616 return ret;
4617 }
4618
4619 static int btrfs_ioctl_get_fslabel(struct btrfs_fs_info *fs_info,
4620 void __user *arg)
4621 {
4622 size_t len;
4623 int ret;
4624 char label[BTRFS_LABEL_SIZE];
4625
4626 spin_lock(&fs_info->super_lock);
4627 memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
4628 spin_unlock(&fs_info->super_lock);
4629
4630 len = strnlen(label, BTRFS_LABEL_SIZE);
4631
4632 if (len == BTRFS_LABEL_SIZE) {
4633 btrfs_warn(fs_info,
4634 "label is too long, return the first %zu bytes",
4635 --len);
4636 }
4637
4638 ret = copy_to_user(arg, label, len);
4639
4640 return ret ? -EFAULT : 0;
4641 }
4642
4643 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
4644 {
4645 struct inode *inode = file_inode(file);
4646 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4647 struct btrfs_root *root = BTRFS_I(inode)->root;
4648 struct btrfs_super_block *super_block = fs_info->super_copy;
4649 struct btrfs_trans_handle *trans;
4650 char label[BTRFS_LABEL_SIZE];
4651 int ret;
4652
4653 if (!capable(CAP_SYS_ADMIN))
4654 return -EPERM;
4655
4656 if (copy_from_user(label, arg, sizeof(label)))
4657 return -EFAULT;
4658
4659 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
4660 btrfs_err(fs_info,
4661 "unable to set label with more than %d bytes",
4662 BTRFS_LABEL_SIZE - 1);
4663 return -EINVAL;
4664 }
4665
4666 ret = mnt_want_write_file(file);
4667 if (ret)
4668 return ret;
4669
4670 trans = btrfs_start_transaction(root, 0);
4671 if (IS_ERR(trans)) {
4672 ret = PTR_ERR(trans);
4673 goto out_unlock;
4674 }
4675
4676 spin_lock(&fs_info->super_lock);
4677 strcpy(super_block->label, label);
4678 spin_unlock(&fs_info->super_lock);
4679 ret = btrfs_commit_transaction(trans);
4680
4681 out_unlock:
4682 mnt_drop_write_file(file);
4683 return ret;
4684 }
4685
4686 #define INIT_FEATURE_FLAGS(suffix) \
4687 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
4688 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
4689 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
4690
4691 int btrfs_ioctl_get_supported_features(void __user *arg)
4692 {
4693 static const struct btrfs_ioctl_feature_flags features[3] = {
4694 INIT_FEATURE_FLAGS(SUPP),
4695 INIT_FEATURE_FLAGS(SAFE_SET),
4696 INIT_FEATURE_FLAGS(SAFE_CLEAR)
4697 };
4698
4699 if (copy_to_user(arg, &features, sizeof(features)))
4700 return -EFAULT;
4701
4702 return 0;
4703 }
4704
4705 static int btrfs_ioctl_get_features(struct btrfs_fs_info *fs_info,
4706 void __user *arg)
4707 {
4708 struct btrfs_super_block *super_block = fs_info->super_copy;
4709 struct btrfs_ioctl_feature_flags features;
4710
4711 features.compat_flags = btrfs_super_compat_flags(super_block);
4712 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
4713 features.incompat_flags = btrfs_super_incompat_flags(super_block);
4714
4715 if (copy_to_user(arg, &features, sizeof(features)))
4716 return -EFAULT;
4717
4718 return 0;
4719 }
4720
4721 static int check_feature_bits(struct btrfs_fs_info *fs_info,
4722 enum btrfs_feature_set set,
4723 u64 change_mask, u64 flags, u64 supported_flags,
4724 u64 safe_set, u64 safe_clear)
4725 {
4726 const char *type = btrfs_feature_set_name(set);
4727 char *names;
4728 u64 disallowed, unsupported;
4729 u64 set_mask = flags & change_mask;
4730 u64 clear_mask = ~flags & change_mask;
4731
4732 unsupported = set_mask & ~supported_flags;
4733 if (unsupported) {
4734 names = btrfs_printable_features(set, unsupported);
4735 if (names) {
4736 btrfs_warn(fs_info,
4737 "this kernel does not support the %s feature bit%s",
4738 names, strchr(names, ',') ? "s" : "");
4739 kfree(names);
4740 } else
4741 btrfs_warn(fs_info,
4742 "this kernel does not support %s bits 0x%llx",
4743 type, unsupported);
4744 return -EOPNOTSUPP;
4745 }
4746
4747 disallowed = set_mask & ~safe_set;
4748 if (disallowed) {
4749 names = btrfs_printable_features(set, disallowed);
4750 if (names) {
4751 btrfs_warn(fs_info,
4752 "can't set the %s feature bit%s while mounted",
4753 names, strchr(names, ',') ? "s" : "");
4754 kfree(names);
4755 } else
4756 btrfs_warn(fs_info,
4757 "can't set %s bits 0x%llx while mounted",
4758 type, disallowed);
4759 return -EPERM;
4760 }
4761
4762 disallowed = clear_mask & ~safe_clear;
4763 if (disallowed) {
4764 names = btrfs_printable_features(set, disallowed);
4765 if (names) {
4766 btrfs_warn(fs_info,
4767 "can't clear the %s feature bit%s while mounted",
4768 names, strchr(names, ',') ? "s" : "");
4769 kfree(names);
4770 } else
4771 btrfs_warn(fs_info,
4772 "can't clear %s bits 0x%llx while mounted",
4773 type, disallowed);
4774 return -EPERM;
4775 }
4776
4777 return 0;
4778 }
4779
4780 #define check_feature(fs_info, change_mask, flags, mask_base) \
4781 check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags, \
4782 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
4783 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
4784 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
4785
4786 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
4787 {
4788 struct inode *inode = file_inode(file);
4789 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4790 struct btrfs_root *root = BTRFS_I(inode)->root;
4791 struct btrfs_super_block *super_block = fs_info->super_copy;
4792 struct btrfs_ioctl_feature_flags flags[2];
4793 struct btrfs_trans_handle *trans;
4794 u64 newflags;
4795 int ret;
4796
4797 if (!capable(CAP_SYS_ADMIN))
4798 return -EPERM;
4799
4800 if (copy_from_user(flags, arg, sizeof(flags)))
4801 return -EFAULT;
4802
4803 /* Nothing to do */
4804 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
4805 !flags[0].incompat_flags)
4806 return 0;
4807
4808 ret = check_feature(fs_info, flags[0].compat_flags,
4809 flags[1].compat_flags, COMPAT);
4810 if (ret)
4811 return ret;
4812
4813 ret = check_feature(fs_info, flags[0].compat_ro_flags,
4814 flags[1].compat_ro_flags, COMPAT_RO);
4815 if (ret)
4816 return ret;
4817
4818 ret = check_feature(fs_info, flags[0].incompat_flags,
4819 flags[1].incompat_flags, INCOMPAT);
4820 if (ret)
4821 return ret;
4822
4823 ret = mnt_want_write_file(file);
4824 if (ret)
4825 return ret;
4826
4827 trans = btrfs_start_transaction(root, 0);
4828 if (IS_ERR(trans)) {
4829 ret = PTR_ERR(trans);
4830 goto out_drop_write;
4831 }
4832
4833 spin_lock(&fs_info->super_lock);
4834 newflags = btrfs_super_compat_flags(super_block);
4835 newflags |= flags[0].compat_flags & flags[1].compat_flags;
4836 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
4837 btrfs_set_super_compat_flags(super_block, newflags);
4838
4839 newflags = btrfs_super_compat_ro_flags(super_block);
4840 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
4841 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
4842 btrfs_set_super_compat_ro_flags(super_block, newflags);
4843
4844 newflags = btrfs_super_incompat_flags(super_block);
4845 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
4846 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
4847 btrfs_set_super_incompat_flags(super_block, newflags);
4848 spin_unlock(&fs_info->super_lock);
4849
4850 ret = btrfs_commit_transaction(trans);
4851 out_drop_write:
4852 mnt_drop_write_file(file);
4853
4854 return ret;
4855 }
4856
4857 static int _btrfs_ioctl_send(struct file *file, void __user *argp, bool compat)
4858 {
4859 struct btrfs_ioctl_send_args *arg;
4860 int ret;
4861
4862 if (compat) {
4863 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4864 struct btrfs_ioctl_send_args_32 args32;
4865
4866 ret = copy_from_user(&args32, argp, sizeof(args32));
4867 if (ret)
4868 return -EFAULT;
4869 arg = kzalloc(sizeof(*arg), GFP_KERNEL);
4870 if (!arg)
4871 return -ENOMEM;
4872 arg->send_fd = args32.send_fd;
4873 arg->clone_sources_count = args32.clone_sources_count;
4874 arg->clone_sources = compat_ptr(args32.clone_sources);
4875 arg->parent_root = args32.parent_root;
4876 arg->flags = args32.flags;
4877 memcpy(arg->reserved, args32.reserved,
4878 sizeof(args32.reserved));
4879 #else
4880 return -ENOTTY;
4881 #endif
4882 } else {
4883 arg = memdup_user(argp, sizeof(*arg));
4884 if (IS_ERR(arg))
4885 return PTR_ERR(arg);
4886 }
4887 ret = btrfs_ioctl_send(file, arg);
4888 kfree(arg);
4889 return ret;
4890 }
4891
4892 long btrfs_ioctl(struct file *file, unsigned int
4893 cmd, unsigned long arg)
4894 {
4895 struct inode *inode = file_inode(file);
4896 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4897 struct btrfs_root *root = BTRFS_I(inode)->root;
4898 void __user *argp = (void __user *)arg;
4899
4900 switch (cmd) {
4901 case FS_IOC_GETVERSION:
4902 return btrfs_ioctl_getversion(file, argp);
4903 case FS_IOC_GETFSLABEL:
4904 return btrfs_ioctl_get_fslabel(fs_info, argp);
4905 case FS_IOC_SETFSLABEL:
4906 return btrfs_ioctl_set_fslabel(file, argp);
4907 case FITRIM:
4908 return btrfs_ioctl_fitrim(fs_info, argp);
4909 case BTRFS_IOC_SNAP_CREATE:
4910 return btrfs_ioctl_snap_create(file, argp, 0);
4911 case BTRFS_IOC_SNAP_CREATE_V2:
4912 return btrfs_ioctl_snap_create_v2(file, argp, 0);
4913 case BTRFS_IOC_SUBVOL_CREATE:
4914 return btrfs_ioctl_snap_create(file, argp, 1);
4915 case BTRFS_IOC_SUBVOL_CREATE_V2:
4916 return btrfs_ioctl_snap_create_v2(file, argp, 1);
4917 case BTRFS_IOC_SNAP_DESTROY:
4918 return btrfs_ioctl_snap_destroy(file, argp, false);
4919 case BTRFS_IOC_SNAP_DESTROY_V2:
4920 return btrfs_ioctl_snap_destroy(file, argp, true);
4921 case BTRFS_IOC_SUBVOL_GETFLAGS:
4922 return btrfs_ioctl_subvol_getflags(file, argp);
4923 case BTRFS_IOC_SUBVOL_SETFLAGS:
4924 return btrfs_ioctl_subvol_setflags(file, argp);
4925 case BTRFS_IOC_DEFAULT_SUBVOL:
4926 return btrfs_ioctl_default_subvol(file, argp);
4927 case BTRFS_IOC_DEFRAG:
4928 return btrfs_ioctl_defrag(file, NULL);
4929 case BTRFS_IOC_DEFRAG_RANGE:
4930 return btrfs_ioctl_defrag(file, argp);
4931 case BTRFS_IOC_RESIZE:
4932 return btrfs_ioctl_resize(file, argp);
4933 case BTRFS_IOC_ADD_DEV:
4934 return btrfs_ioctl_add_dev(fs_info, argp);
4935 case BTRFS_IOC_RM_DEV:
4936 return btrfs_ioctl_rm_dev(file, argp);
4937 case BTRFS_IOC_RM_DEV_V2:
4938 return btrfs_ioctl_rm_dev_v2(file, argp);
4939 case BTRFS_IOC_FS_INFO:
4940 return btrfs_ioctl_fs_info(fs_info, argp);
4941 case BTRFS_IOC_DEV_INFO:
4942 return btrfs_ioctl_dev_info(fs_info, argp);
4943 case BTRFS_IOC_BALANCE:
4944 return btrfs_ioctl_balance(file, NULL);
4945 case BTRFS_IOC_TREE_SEARCH:
4946 return btrfs_ioctl_tree_search(file, argp);
4947 case BTRFS_IOC_TREE_SEARCH_V2:
4948 return btrfs_ioctl_tree_search_v2(file, argp);
4949 case BTRFS_IOC_INO_LOOKUP:
4950 return btrfs_ioctl_ino_lookup(file, argp);
4951 case BTRFS_IOC_INO_PATHS:
4952 return btrfs_ioctl_ino_to_path(root, argp);
4953 case BTRFS_IOC_LOGICAL_INO:
4954 return btrfs_ioctl_logical_to_ino(fs_info, argp, 1);
4955 case BTRFS_IOC_LOGICAL_INO_V2:
4956 return btrfs_ioctl_logical_to_ino(fs_info, argp, 2);
4957 case BTRFS_IOC_SPACE_INFO:
4958 return btrfs_ioctl_space_info(fs_info, argp);
4959 case BTRFS_IOC_SYNC: {
4960 int ret;
4961
4962 ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false);
4963 if (ret)
4964 return ret;
4965 ret = btrfs_sync_fs(inode->i_sb, 1);
4966 /*
4967 * The transaction thread may want to do more work,
4968 * namely it pokes the cleaner kthread that will start
4969 * processing uncleaned subvols.
4970 */
4971 wake_up_process(fs_info->transaction_kthread);
4972 return ret;
4973 }
4974 case BTRFS_IOC_START_SYNC:
4975 return btrfs_ioctl_start_sync(root, argp);
4976 case BTRFS_IOC_WAIT_SYNC:
4977 return btrfs_ioctl_wait_sync(fs_info, argp);
4978 case BTRFS_IOC_SCRUB:
4979 return btrfs_ioctl_scrub(file, argp);
4980 case BTRFS_IOC_SCRUB_CANCEL:
4981 return btrfs_ioctl_scrub_cancel(fs_info);
4982 case BTRFS_IOC_SCRUB_PROGRESS:
4983 return btrfs_ioctl_scrub_progress(fs_info, argp);
4984 case BTRFS_IOC_BALANCE_V2:
4985 return btrfs_ioctl_balance(file, argp);
4986 case BTRFS_IOC_BALANCE_CTL:
4987 return btrfs_ioctl_balance_ctl(fs_info, arg);
4988 case BTRFS_IOC_BALANCE_PROGRESS:
4989 return btrfs_ioctl_balance_progress(fs_info, argp);
4990 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
4991 return btrfs_ioctl_set_received_subvol(file, argp);
4992 #ifdef CONFIG_64BIT
4993 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
4994 return btrfs_ioctl_set_received_subvol_32(file, argp);
4995 #endif
4996 case BTRFS_IOC_SEND:
4997 return _btrfs_ioctl_send(file, argp, false);
4998 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4999 case BTRFS_IOC_SEND_32:
5000 return _btrfs_ioctl_send(file, argp, true);
5001 #endif
5002 case BTRFS_IOC_GET_DEV_STATS:
5003 return btrfs_ioctl_get_dev_stats(fs_info, argp);
5004 case BTRFS_IOC_QUOTA_CTL:
5005 return btrfs_ioctl_quota_ctl(file, argp);
5006 case BTRFS_IOC_QGROUP_ASSIGN:
5007 return btrfs_ioctl_qgroup_assign(file, argp);
5008 case BTRFS_IOC_QGROUP_CREATE:
5009 return btrfs_ioctl_qgroup_create(file, argp);
5010 case BTRFS_IOC_QGROUP_LIMIT:
5011 return btrfs_ioctl_qgroup_limit(file, argp);
5012 case BTRFS_IOC_QUOTA_RESCAN:
5013 return btrfs_ioctl_quota_rescan(file, argp);
5014 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5015 return btrfs_ioctl_quota_rescan_status(fs_info, argp);
5016 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5017 return btrfs_ioctl_quota_rescan_wait(fs_info, argp);
5018 case BTRFS_IOC_DEV_REPLACE:
5019 return btrfs_ioctl_dev_replace(fs_info, argp);
5020 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5021 return btrfs_ioctl_get_supported_features(argp);
5022 case BTRFS_IOC_GET_FEATURES:
5023 return btrfs_ioctl_get_features(fs_info, argp);
5024 case BTRFS_IOC_SET_FEATURES:
5025 return btrfs_ioctl_set_features(file, argp);
5026 case BTRFS_IOC_GET_SUBVOL_INFO:
5027 return btrfs_ioctl_get_subvol_info(file, argp);
5028 case BTRFS_IOC_GET_SUBVOL_ROOTREF:
5029 return btrfs_ioctl_get_subvol_rootref(file, argp);
5030 case BTRFS_IOC_INO_LOOKUP_USER:
5031 return btrfs_ioctl_ino_lookup_user(file, argp);
5032 case FS_IOC_ENABLE_VERITY:
5033 return fsverity_ioctl_enable(file, (const void __user *)argp);
5034 case FS_IOC_MEASURE_VERITY:
5035 return fsverity_ioctl_measure(file, argp);
5036 }
5037
5038 return -ENOTTY;
5039 }
5040
5041 #ifdef CONFIG_COMPAT
5042 long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
5043 {
5044 /*
5045 * These all access 32-bit values anyway so no further
5046 * handling is necessary.
5047 */
5048 switch (cmd) {
5049 case FS_IOC32_GETVERSION:
5050 cmd = FS_IOC_GETVERSION;
5051 break;
5052 }
5053
5054 return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
5055 }
5056 #endif
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