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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 <linux/sched/xacct.h>
32#include "ctree.h"
33#include "disk-io.h"
34#include "export.h"
35#include "transaction.h"
36#include "btrfs_inode.h"
37#include "volumes.h"
38#include "locking.h"
39#include "backref.h"
40#include "send.h"
41#include "dev-replace.h"
42#include "props.h"
43#include "sysfs.h"
44#include "qgroup.h"
45#include "tree-log.h"
46#include "compression.h"
47#include "space-info.h"
48#include "block-group.h"
49#include "fs.h"
50#include "accessors.h"
51#include "extent-tree.h"
52#include "root-tree.h"
53#include "defrag.h"
54#include "dir-item.h"
55#include "uuid-tree.h"
56#include "ioctl.h"
57#include "file.h"
58#include "scrub.h"
59#include "super.h"
60
61#ifdef CONFIG_64BIT
62/* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
63 * structures are incorrect, as the timespec structure from userspace
64 * is 4 bytes too small. We define these alternatives here to teach
65 * the kernel about the 32-bit struct packing.
66 */
67struct btrfs_ioctl_timespec_32 {
68 __u64 sec;
69 __u32 nsec;
70} __attribute__ ((__packed__));
71
72struct btrfs_ioctl_received_subvol_args_32 {
73 char uuid[BTRFS_UUID_SIZE]; /* in */
74 __u64 stransid; /* in */
75 __u64 rtransid; /* out */
76 struct btrfs_ioctl_timespec_32 stime; /* in */
77 struct btrfs_ioctl_timespec_32 rtime; /* out */
78 __u64 flags; /* in */
79 __u64 reserved[16]; /* in */
80} __attribute__ ((__packed__));
81
82#define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
83 struct btrfs_ioctl_received_subvol_args_32)
84#endif
85
86#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
87struct btrfs_ioctl_send_args_32 {
88 __s64 send_fd; /* in */
89 __u64 clone_sources_count; /* in */
90 compat_uptr_t clone_sources; /* in */
91 __u64 parent_root; /* in */
92 __u64 flags; /* in */
93 __u32 version; /* in */
94 __u8 reserved[28]; /* in */
95} __attribute__ ((__packed__));
96
97#define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \
98 struct btrfs_ioctl_send_args_32)
99
100struct btrfs_ioctl_encoded_io_args_32 {
101 compat_uptr_t iov;
102 compat_ulong_t iovcnt;
103 __s64 offset;
104 __u64 flags;
105 __u64 len;
106 __u64 unencoded_len;
107 __u64 unencoded_offset;
108 __u32 compression;
109 __u32 encryption;
110 __u8 reserved[64];
111};
112
113#define BTRFS_IOC_ENCODED_READ_32 _IOR(BTRFS_IOCTL_MAGIC, 64, \
114 struct btrfs_ioctl_encoded_io_args_32)
115#define BTRFS_IOC_ENCODED_WRITE_32 _IOW(BTRFS_IOCTL_MAGIC, 64, \
116 struct btrfs_ioctl_encoded_io_args_32)
117#endif
118
119/* Mask out flags that are inappropriate for the given type of inode. */
120static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,
121 unsigned int flags)
122{
123 if (S_ISDIR(inode->i_mode))
124 return flags;
125 else if (S_ISREG(inode->i_mode))
126 return flags & ~FS_DIRSYNC_FL;
127 else
128 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
129}
130
131/*
132 * Export internal inode flags to the format expected by the FS_IOC_GETFLAGS
133 * ioctl.
134 */
135static unsigned int btrfs_inode_flags_to_fsflags(struct btrfs_inode *binode)
136{
137 unsigned int iflags = 0;
138 u32 flags = binode->flags;
139 u32 ro_flags = binode->ro_flags;
140
141 if (flags & BTRFS_INODE_SYNC)
142 iflags |= FS_SYNC_FL;
143 if (flags & BTRFS_INODE_IMMUTABLE)
144 iflags |= FS_IMMUTABLE_FL;
145 if (flags & BTRFS_INODE_APPEND)
146 iflags |= FS_APPEND_FL;
147 if (flags & BTRFS_INODE_NODUMP)
148 iflags |= FS_NODUMP_FL;
149 if (flags & BTRFS_INODE_NOATIME)
150 iflags |= FS_NOATIME_FL;
151 if (flags & BTRFS_INODE_DIRSYNC)
152 iflags |= FS_DIRSYNC_FL;
153 if (flags & BTRFS_INODE_NODATACOW)
154 iflags |= FS_NOCOW_FL;
155 if (ro_flags & BTRFS_INODE_RO_VERITY)
156 iflags |= FS_VERITY_FL;
157
158 if (flags & BTRFS_INODE_NOCOMPRESS)
159 iflags |= FS_NOCOMP_FL;
160 else if (flags & BTRFS_INODE_COMPRESS)
161 iflags |= FS_COMPR_FL;
162
163 return iflags;
164}
165
166/*
167 * Update inode->i_flags based on the btrfs internal flags.
168 */
169void btrfs_sync_inode_flags_to_i_flags(struct inode *inode)
170{
171 struct btrfs_inode *binode = BTRFS_I(inode);
172 unsigned int new_fl = 0;
173
174 if (binode->flags & BTRFS_INODE_SYNC)
175 new_fl |= S_SYNC;
176 if (binode->flags & BTRFS_INODE_IMMUTABLE)
177 new_fl |= S_IMMUTABLE;
178 if (binode->flags & BTRFS_INODE_APPEND)
179 new_fl |= S_APPEND;
180 if (binode->flags & BTRFS_INODE_NOATIME)
181 new_fl |= S_NOATIME;
182 if (binode->flags & BTRFS_INODE_DIRSYNC)
183 new_fl |= S_DIRSYNC;
184 if (binode->ro_flags & BTRFS_INODE_RO_VERITY)
185 new_fl |= S_VERITY;
186
187 set_mask_bits(&inode->i_flags,
188 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC |
189 S_VERITY, new_fl);
190}
191
192/*
193 * Check if @flags are a supported and valid set of FS_*_FL flags and that
194 * the old and new flags are not conflicting
195 */
196static int check_fsflags(unsigned int old_flags, unsigned int flags)
197{
198 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
199 FS_NOATIME_FL | FS_NODUMP_FL | \
200 FS_SYNC_FL | FS_DIRSYNC_FL | \
201 FS_NOCOMP_FL | FS_COMPR_FL |
202 FS_NOCOW_FL))
203 return -EOPNOTSUPP;
204
205 /* COMPR and NOCOMP on new/old are valid */
206 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
207 return -EINVAL;
208
209 if ((flags & FS_COMPR_FL) && (flags & FS_NOCOW_FL))
210 return -EINVAL;
211
212 /* NOCOW and compression options are mutually exclusive */
213 if ((old_flags & FS_NOCOW_FL) && (flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
214 return -EINVAL;
215 if ((flags & FS_NOCOW_FL) && (old_flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
216 return -EINVAL;
217
218 return 0;
219}
220
221static int check_fsflags_compatible(struct btrfs_fs_info *fs_info,
222 unsigned int flags)
223{
224 if (btrfs_is_zoned(fs_info) && (flags & FS_NOCOW_FL))
225 return -EPERM;
226
227 return 0;
228}
229
230int btrfs_check_ioctl_vol_args_path(const struct btrfs_ioctl_vol_args *vol_args)
231{
232 if (memchr(vol_args->name, 0, sizeof(vol_args->name)) == NULL)
233 return -ENAMETOOLONG;
234 return 0;
235}
236
237static int btrfs_check_ioctl_vol_args2_subvol_name(const struct btrfs_ioctl_vol_args_v2 *vol_args2)
238{
239 if (memchr(vol_args2->name, 0, sizeof(vol_args2->name)) == NULL)
240 return -ENAMETOOLONG;
241 return 0;
242}
243
244/*
245 * Set flags/xflags from the internal inode flags. The remaining items of
246 * fsxattr are zeroed.
247 */
248int btrfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
249{
250 struct btrfs_inode *binode = BTRFS_I(d_inode(dentry));
251
252 fileattr_fill_flags(fa, btrfs_inode_flags_to_fsflags(binode));
253 return 0;
254}
255
256int btrfs_fileattr_set(struct mnt_idmap *idmap,
257 struct dentry *dentry, struct fileattr *fa)
258{
259 struct inode *inode = d_inode(dentry);
260 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
261 struct btrfs_inode *binode = BTRFS_I(inode);
262 struct btrfs_root *root = binode->root;
263 struct btrfs_trans_handle *trans;
264 unsigned int fsflags, old_fsflags;
265 int ret;
266 const char *comp = NULL;
267 u32 binode_flags;
268
269 if (btrfs_root_readonly(root))
270 return -EROFS;
271
272 if (fileattr_has_fsx(fa))
273 return -EOPNOTSUPP;
274
275 fsflags = btrfs_mask_fsflags_for_type(inode, fa->flags);
276 old_fsflags = btrfs_inode_flags_to_fsflags(binode);
277 ret = check_fsflags(old_fsflags, fsflags);
278 if (ret)
279 return ret;
280
281 ret = check_fsflags_compatible(fs_info, fsflags);
282 if (ret)
283 return ret;
284
285 binode_flags = binode->flags;
286 if (fsflags & FS_SYNC_FL)
287 binode_flags |= BTRFS_INODE_SYNC;
288 else
289 binode_flags &= ~BTRFS_INODE_SYNC;
290 if (fsflags & FS_IMMUTABLE_FL)
291 binode_flags |= BTRFS_INODE_IMMUTABLE;
292 else
293 binode_flags &= ~BTRFS_INODE_IMMUTABLE;
294 if (fsflags & FS_APPEND_FL)
295 binode_flags |= BTRFS_INODE_APPEND;
296 else
297 binode_flags &= ~BTRFS_INODE_APPEND;
298 if (fsflags & FS_NODUMP_FL)
299 binode_flags |= BTRFS_INODE_NODUMP;
300 else
301 binode_flags &= ~BTRFS_INODE_NODUMP;
302 if (fsflags & FS_NOATIME_FL)
303 binode_flags |= BTRFS_INODE_NOATIME;
304 else
305 binode_flags &= ~BTRFS_INODE_NOATIME;
306
307 /* If coming from FS_IOC_FSSETXATTR then skip unconverted flags */
308 if (!fa->flags_valid) {
309 /* 1 item for the inode */
310 trans = btrfs_start_transaction(root, 1);
311 if (IS_ERR(trans))
312 return PTR_ERR(trans);
313 goto update_flags;
314 }
315
316 if (fsflags & FS_DIRSYNC_FL)
317 binode_flags |= BTRFS_INODE_DIRSYNC;
318 else
319 binode_flags &= ~BTRFS_INODE_DIRSYNC;
320 if (fsflags & FS_NOCOW_FL) {
321 if (S_ISREG(inode->i_mode)) {
322 /*
323 * It's safe to turn csums off here, no extents exist.
324 * Otherwise we want the flag to reflect the real COW
325 * status of the file and will not set it.
326 */
327 if (inode->i_size == 0)
328 binode_flags |= BTRFS_INODE_NODATACOW |
329 BTRFS_INODE_NODATASUM;
330 } else {
331 binode_flags |= BTRFS_INODE_NODATACOW;
332 }
333 } else {
334 /*
335 * Revert back under same assumptions as above
336 */
337 if (S_ISREG(inode->i_mode)) {
338 if (inode->i_size == 0)
339 binode_flags &= ~(BTRFS_INODE_NODATACOW |
340 BTRFS_INODE_NODATASUM);
341 } else {
342 binode_flags &= ~BTRFS_INODE_NODATACOW;
343 }
344 }
345
346 /*
347 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
348 * flag may be changed automatically if compression code won't make
349 * things smaller.
350 */
351 if (fsflags & FS_NOCOMP_FL) {
352 binode_flags &= ~BTRFS_INODE_COMPRESS;
353 binode_flags |= BTRFS_INODE_NOCOMPRESS;
354 } else if (fsflags & FS_COMPR_FL) {
355
356 if (IS_SWAPFILE(inode))
357 return -ETXTBSY;
358
359 binode_flags |= BTRFS_INODE_COMPRESS;
360 binode_flags &= ~BTRFS_INODE_NOCOMPRESS;
361
362 comp = btrfs_compress_type2str(fs_info->compress_type);
363 if (!comp || comp[0] == 0)
364 comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);
365 } else {
366 binode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
367 }
368
369 /*
370 * 1 for inode item
371 * 2 for properties
372 */
373 trans = btrfs_start_transaction(root, 3);
374 if (IS_ERR(trans))
375 return PTR_ERR(trans);
376
377 if (comp) {
378 ret = btrfs_set_prop(trans, inode, "btrfs.compression", comp,
379 strlen(comp), 0);
380 if (ret) {
381 btrfs_abort_transaction(trans, ret);
382 goto out_end_trans;
383 }
384 } else {
385 ret = btrfs_set_prop(trans, inode, "btrfs.compression", NULL,
386 0, 0);
387 if (ret && ret != -ENODATA) {
388 btrfs_abort_transaction(trans, ret);
389 goto out_end_trans;
390 }
391 }
392
393update_flags:
394 binode->flags = binode_flags;
395 btrfs_sync_inode_flags_to_i_flags(inode);
396 inode_inc_iversion(inode);
397 inode_set_ctime_current(inode);
398 ret = btrfs_update_inode(trans, BTRFS_I(inode));
399
400 out_end_trans:
401 btrfs_end_transaction(trans);
402 return ret;
403}
404
405/*
406 * Start exclusive operation @type, return true on success
407 */
408bool btrfs_exclop_start(struct btrfs_fs_info *fs_info,
409 enum btrfs_exclusive_operation type)
410{
411 bool ret = false;
412
413 spin_lock(&fs_info->super_lock);
414 if (fs_info->exclusive_operation == BTRFS_EXCLOP_NONE) {
415 fs_info->exclusive_operation = type;
416 ret = true;
417 }
418 spin_unlock(&fs_info->super_lock);
419
420 return ret;
421}
422
423/*
424 * Conditionally allow to enter the exclusive operation in case it's compatible
425 * with the running one. This must be paired with btrfs_exclop_start_unlock and
426 * btrfs_exclop_finish.
427 *
428 * Compatibility:
429 * - the same type is already running
430 * - when trying to add a device and balance has been paused
431 * - not BTRFS_EXCLOP_NONE - this is intentionally incompatible and the caller
432 * must check the condition first that would allow none -> @type
433 */
434bool btrfs_exclop_start_try_lock(struct btrfs_fs_info *fs_info,
435 enum btrfs_exclusive_operation type)
436{
437 spin_lock(&fs_info->super_lock);
438 if (fs_info->exclusive_operation == type ||
439 (fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED &&
440 type == BTRFS_EXCLOP_DEV_ADD))
441 return true;
442
443 spin_unlock(&fs_info->super_lock);
444 return false;
445}
446
447void btrfs_exclop_start_unlock(struct btrfs_fs_info *fs_info)
448{
449 spin_unlock(&fs_info->super_lock);
450}
451
452void btrfs_exclop_finish(struct btrfs_fs_info *fs_info)
453{
454 spin_lock(&fs_info->super_lock);
455 WRITE_ONCE(fs_info->exclusive_operation, BTRFS_EXCLOP_NONE);
456 spin_unlock(&fs_info->super_lock);
457 sysfs_notify(&fs_info->fs_devices->fsid_kobj, NULL, "exclusive_operation");
458}
459
460void btrfs_exclop_balance(struct btrfs_fs_info *fs_info,
461 enum btrfs_exclusive_operation op)
462{
463 switch (op) {
464 case BTRFS_EXCLOP_BALANCE_PAUSED:
465 spin_lock(&fs_info->super_lock);
466 ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE ||
467 fs_info->exclusive_operation == BTRFS_EXCLOP_DEV_ADD ||
468 fs_info->exclusive_operation == BTRFS_EXCLOP_NONE ||
469 fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED);
470 fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE_PAUSED;
471 spin_unlock(&fs_info->super_lock);
472 break;
473 case BTRFS_EXCLOP_BALANCE:
474 spin_lock(&fs_info->super_lock);
475 ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED);
476 fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE;
477 spin_unlock(&fs_info->super_lock);
478 break;
479 default:
480 btrfs_warn(fs_info,
481 "invalid exclop balance operation %d requested", op);
482 }
483}
484
485static int btrfs_ioctl_getversion(struct inode *inode, int __user *arg)
486{
487 return put_user(inode->i_generation, arg);
488}
489
490static noinline int btrfs_ioctl_fitrim(struct btrfs_fs_info *fs_info,
491 void __user *arg)
492{
493 struct btrfs_device *device;
494 struct fstrim_range range;
495 u64 minlen = ULLONG_MAX;
496 u64 num_devices = 0;
497 int ret;
498
499 if (!capable(CAP_SYS_ADMIN))
500 return -EPERM;
501
502 /*
503 * btrfs_trim_block_group() depends on space cache, which is not
504 * available in zoned filesystem. So, disallow fitrim on a zoned
505 * filesystem for now.
506 */
507 if (btrfs_is_zoned(fs_info))
508 return -EOPNOTSUPP;
509
510 /*
511 * If the fs is mounted with nologreplay, which requires it to be
512 * mounted in RO mode as well, we can not allow discard on free space
513 * inside block groups, because log trees refer to extents that are not
514 * pinned in a block group's free space cache (pinning the extents is
515 * precisely the first phase of replaying a log tree).
516 */
517 if (btrfs_test_opt(fs_info, NOLOGREPLAY))
518 return -EROFS;
519
520 rcu_read_lock();
521 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
522 dev_list) {
523 if (!device->bdev || !bdev_max_discard_sectors(device->bdev))
524 continue;
525 num_devices++;
526 minlen = min_t(u64, bdev_discard_granularity(device->bdev),
527 minlen);
528 }
529 rcu_read_unlock();
530
531 if (!num_devices)
532 return -EOPNOTSUPP;
533 if (copy_from_user(&range, arg, sizeof(range)))
534 return -EFAULT;
535
536 /*
537 * NOTE: Don't truncate the range using super->total_bytes. Bytenr of
538 * block group is in the logical address space, which can be any
539 * sectorsize aligned bytenr in the range [0, U64_MAX].
540 */
541 if (range.len < fs_info->sectorsize)
542 return -EINVAL;
543
544 range.minlen = max(range.minlen, minlen);
545 ret = btrfs_trim_fs(fs_info, &range);
546 if (ret < 0)
547 return ret;
548
549 if (copy_to_user(arg, &range, sizeof(range)))
550 return -EFAULT;
551
552 return 0;
553}
554
555int __pure btrfs_is_empty_uuid(u8 *uuid)
556{
557 int i;
558
559 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
560 if (uuid[i])
561 return 0;
562 }
563 return 1;
564}
565
566/*
567 * Calculate the number of transaction items to reserve for creating a subvolume
568 * or snapshot, not including the inode, directory entries, or parent directory.
569 */
570static unsigned int create_subvol_num_items(struct btrfs_qgroup_inherit *inherit)
571{
572 /*
573 * 1 to add root block
574 * 1 to add root item
575 * 1 to add root ref
576 * 1 to add root backref
577 * 1 to add UUID item
578 * 1 to add qgroup info
579 * 1 to add qgroup limit
580 *
581 * Ideally the last two would only be accounted if qgroups are enabled,
582 * but that can change between now and the time we would insert them.
583 */
584 unsigned int num_items = 7;
585
586 if (inherit) {
587 /* 2 to add qgroup relations for each inherited qgroup */
588 num_items += 2 * inherit->num_qgroups;
589 }
590 return num_items;
591}
592
593static noinline int create_subvol(struct mnt_idmap *idmap,
594 struct inode *dir, struct dentry *dentry,
595 struct btrfs_qgroup_inherit *inherit)
596{
597 struct btrfs_fs_info *fs_info = inode_to_fs_info(dir);
598 struct btrfs_trans_handle *trans;
599 struct btrfs_key key;
600 struct btrfs_root_item *root_item;
601 struct btrfs_inode_item *inode_item;
602 struct extent_buffer *leaf;
603 struct btrfs_root *root = BTRFS_I(dir)->root;
604 struct btrfs_root *new_root;
605 struct btrfs_block_rsv block_rsv;
606 struct timespec64 cur_time = current_time(dir);
607 struct btrfs_new_inode_args new_inode_args = {
608 .dir = dir,
609 .dentry = dentry,
610 .subvol = true,
611 };
612 unsigned int trans_num_items;
613 int ret;
614 dev_t anon_dev;
615 u64 objectid;
616 u64 qgroup_reserved = 0;
617
618 root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
619 if (!root_item)
620 return -ENOMEM;
621
622 ret = btrfs_get_free_objectid(fs_info->tree_root, &objectid);
623 if (ret)
624 goto out_root_item;
625
626 /*
627 * Don't create subvolume whose level is not zero. Or qgroup will be
628 * screwed up since it assumes subvolume qgroup's level to be 0.
629 */
630 if (btrfs_qgroup_level(objectid)) {
631 ret = -ENOSPC;
632 goto out_root_item;
633 }
634
635 ret = get_anon_bdev(&anon_dev);
636 if (ret < 0)
637 goto out_root_item;
638
639 new_inode_args.inode = btrfs_new_subvol_inode(idmap, dir);
640 if (!new_inode_args.inode) {
641 ret = -ENOMEM;
642 goto out_anon_dev;
643 }
644 ret = btrfs_new_inode_prepare(&new_inode_args, &trans_num_items);
645 if (ret)
646 goto out_inode;
647 trans_num_items += create_subvol_num_items(inherit);
648
649 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
650 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
651 trans_num_items, false);
652 if (ret)
653 goto out_new_inode_args;
654 qgroup_reserved = block_rsv.qgroup_rsv_reserved;
655
656 trans = btrfs_start_transaction(root, 0);
657 if (IS_ERR(trans)) {
658 ret = PTR_ERR(trans);
659 goto out_release_rsv;
660 }
661 ret = btrfs_record_root_in_trans(trans, BTRFS_I(dir)->root);
662 if (ret)
663 goto out;
664 btrfs_qgroup_convert_reserved_meta(root, qgroup_reserved);
665 qgroup_reserved = 0;
666 trans->block_rsv = &block_rsv;
667 trans->bytes_reserved = block_rsv.size;
668 /* Tree log can't currently deal with an inode which is a new root. */
669 btrfs_set_log_full_commit(trans);
670
671 ret = btrfs_qgroup_inherit(trans, 0, objectid, root->root_key.objectid, inherit);
672 if (ret)
673 goto out;
674
675 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0,
676 0, BTRFS_NESTING_NORMAL);
677 if (IS_ERR(leaf)) {
678 ret = PTR_ERR(leaf);
679 goto out;
680 }
681
682 btrfs_mark_buffer_dirty(trans, leaf);
683
684 inode_item = &root_item->inode;
685 btrfs_set_stack_inode_generation(inode_item, 1);
686 btrfs_set_stack_inode_size(inode_item, 3);
687 btrfs_set_stack_inode_nlink(inode_item, 1);
688 btrfs_set_stack_inode_nbytes(inode_item,
689 fs_info->nodesize);
690 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
691
692 btrfs_set_root_flags(root_item, 0);
693 btrfs_set_root_limit(root_item, 0);
694 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
695
696 btrfs_set_root_bytenr(root_item, leaf->start);
697 btrfs_set_root_generation(root_item, trans->transid);
698 btrfs_set_root_level(root_item, 0);
699 btrfs_set_root_refs(root_item, 1);
700 btrfs_set_root_used(root_item, leaf->len);
701 btrfs_set_root_last_snapshot(root_item, 0);
702
703 btrfs_set_root_generation_v2(root_item,
704 btrfs_root_generation(root_item));
705 generate_random_guid(root_item->uuid);
706 btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);
707 btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);
708 root_item->ctime = root_item->otime;
709 btrfs_set_root_ctransid(root_item, trans->transid);
710 btrfs_set_root_otransid(root_item, trans->transid);
711
712 btrfs_tree_unlock(leaf);
713
714 btrfs_set_root_dirid(root_item, BTRFS_FIRST_FREE_OBJECTID);
715
716 key.objectid = objectid;
717 key.offset = 0;
718 key.type = BTRFS_ROOT_ITEM_KEY;
719 ret = btrfs_insert_root(trans, fs_info->tree_root, &key,
720 root_item);
721 if (ret) {
722 /*
723 * Since we don't abort the transaction in this case, free the
724 * tree block so that we don't leak space and leave the
725 * filesystem in an inconsistent state (an extent item in the
726 * extent tree with a backreference for a root that does not
727 * exists).
728 */
729 btrfs_tree_lock(leaf);
730 btrfs_clear_buffer_dirty(trans, leaf);
731 btrfs_tree_unlock(leaf);
732 btrfs_free_tree_block(trans, objectid, leaf, 0, 1);
733 free_extent_buffer(leaf);
734 goto out;
735 }
736
737 free_extent_buffer(leaf);
738 leaf = NULL;
739
740 new_root = btrfs_get_new_fs_root(fs_info, objectid, &anon_dev);
741 if (IS_ERR(new_root)) {
742 ret = PTR_ERR(new_root);
743 btrfs_abort_transaction(trans, ret);
744 goto out;
745 }
746 /* anon_dev is owned by new_root now. */
747 anon_dev = 0;
748 BTRFS_I(new_inode_args.inode)->root = new_root;
749 /* ... and new_root is owned by new_inode_args.inode now. */
750
751 ret = btrfs_record_root_in_trans(trans, new_root);
752 if (ret) {
753 btrfs_abort_transaction(trans, ret);
754 goto out;
755 }
756
757 ret = btrfs_uuid_tree_add(trans, root_item->uuid,
758 BTRFS_UUID_KEY_SUBVOL, objectid);
759 if (ret) {
760 btrfs_abort_transaction(trans, ret);
761 goto out;
762 }
763
764 ret = btrfs_create_new_inode(trans, &new_inode_args);
765 if (ret) {
766 btrfs_abort_transaction(trans, ret);
767 goto out;
768 }
769
770 d_instantiate_new(dentry, new_inode_args.inode);
771 new_inode_args.inode = NULL;
772
773out:
774 trans->block_rsv = NULL;
775 trans->bytes_reserved = 0;
776 btrfs_end_transaction(trans);
777out_release_rsv:
778 btrfs_block_rsv_release(fs_info, &block_rsv, (u64)-1, NULL);
779 if (qgroup_reserved)
780 btrfs_qgroup_free_meta_prealloc(root, qgroup_reserved);
781out_new_inode_args:
782 btrfs_new_inode_args_destroy(&new_inode_args);
783out_inode:
784 iput(new_inode_args.inode);
785out_anon_dev:
786 if (anon_dev)
787 free_anon_bdev(anon_dev);
788out_root_item:
789 kfree(root_item);
790 return ret;
791}
792
793static int create_snapshot(struct btrfs_root *root, struct inode *dir,
794 struct dentry *dentry, bool readonly,
795 struct btrfs_qgroup_inherit *inherit)
796{
797 struct btrfs_fs_info *fs_info = inode_to_fs_info(dir);
798 struct inode *inode;
799 struct btrfs_pending_snapshot *pending_snapshot;
800 unsigned int trans_num_items;
801 struct btrfs_trans_handle *trans;
802 struct btrfs_block_rsv *block_rsv;
803 u64 qgroup_reserved = 0;
804 int ret;
805
806 /* We do not support snapshotting right now. */
807 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
808 btrfs_warn(fs_info,
809 "extent tree v2 doesn't support snapshotting yet");
810 return -EOPNOTSUPP;
811 }
812
813 if (btrfs_root_refs(&root->root_item) == 0)
814 return -ENOENT;
815
816 if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
817 return -EINVAL;
818
819 if (atomic_read(&root->nr_swapfiles)) {
820 btrfs_warn(fs_info,
821 "cannot snapshot subvolume with active swapfile");
822 return -ETXTBSY;
823 }
824
825 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL);
826 if (!pending_snapshot)
827 return -ENOMEM;
828
829 ret = get_anon_bdev(&pending_snapshot->anon_dev);
830 if (ret < 0)
831 goto free_pending;
832 pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
833 GFP_KERNEL);
834 pending_snapshot->path = btrfs_alloc_path();
835 if (!pending_snapshot->root_item || !pending_snapshot->path) {
836 ret = -ENOMEM;
837 goto free_pending;
838 }
839
840 block_rsv = &pending_snapshot->block_rsv;
841 btrfs_init_block_rsv(block_rsv, BTRFS_BLOCK_RSV_TEMP);
842 /*
843 * 1 to add dir item
844 * 1 to add dir index
845 * 1 to update parent inode item
846 */
847 trans_num_items = create_subvol_num_items(inherit) + 3;
848 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root, block_rsv,
849 trans_num_items, false);
850 if (ret)
851 goto free_pending;
852 qgroup_reserved = block_rsv->qgroup_rsv_reserved;
853
854 pending_snapshot->dentry = dentry;
855 pending_snapshot->root = root;
856 pending_snapshot->readonly = readonly;
857 pending_snapshot->dir = dir;
858 pending_snapshot->inherit = inherit;
859
860 trans = btrfs_start_transaction(root, 0);
861 if (IS_ERR(trans)) {
862 ret = PTR_ERR(trans);
863 goto fail;
864 }
865 ret = btrfs_record_root_in_trans(trans, BTRFS_I(dir)->root);
866 if (ret) {
867 btrfs_end_transaction(trans);
868 goto fail;
869 }
870 btrfs_qgroup_convert_reserved_meta(root, qgroup_reserved);
871 qgroup_reserved = 0;
872
873 trans->pending_snapshot = pending_snapshot;
874
875 ret = btrfs_commit_transaction(trans);
876 if (ret)
877 goto fail;
878
879 ret = pending_snapshot->error;
880 if (ret)
881 goto fail;
882
883 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
884 if (ret)
885 goto fail;
886
887 inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
888 if (IS_ERR(inode)) {
889 ret = PTR_ERR(inode);
890 goto fail;
891 }
892
893 d_instantiate(dentry, inode);
894 ret = 0;
895 pending_snapshot->anon_dev = 0;
896fail:
897 /* Prevent double freeing of anon_dev */
898 if (ret && pending_snapshot->snap)
899 pending_snapshot->snap->anon_dev = 0;
900 btrfs_put_root(pending_snapshot->snap);
901 btrfs_block_rsv_release(fs_info, block_rsv, (u64)-1, NULL);
902 if (qgroup_reserved)
903 btrfs_qgroup_free_meta_prealloc(root, qgroup_reserved);
904free_pending:
905 if (pending_snapshot->anon_dev)
906 free_anon_bdev(pending_snapshot->anon_dev);
907 kfree(pending_snapshot->root_item);
908 btrfs_free_path(pending_snapshot->path);
909 kfree(pending_snapshot);
910
911 return ret;
912}
913
914/* copy of may_delete in fs/namei.c()
915 * Check whether we can remove a link victim from directory dir, check
916 * whether the type of victim is right.
917 * 1. We can't do it if dir is read-only (done in permission())
918 * 2. We should have write and exec permissions on dir
919 * 3. We can't remove anything from append-only dir
920 * 4. We can't do anything with immutable dir (done in permission())
921 * 5. If the sticky bit on dir is set we should either
922 * a. be owner of dir, or
923 * b. be owner of victim, or
924 * c. have CAP_FOWNER capability
925 * 6. If the victim is append-only or immutable we can't do anything with
926 * links pointing to it.
927 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
928 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
929 * 9. We can't remove a root or mountpoint.
930 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
931 * nfs_async_unlink().
932 */
933
934static int btrfs_may_delete(struct mnt_idmap *idmap,
935 struct inode *dir, struct dentry *victim, int isdir)
936{
937 int error;
938
939 if (d_really_is_negative(victim))
940 return -ENOENT;
941
942 /* The @victim is not inside @dir. */
943 if (d_inode(victim->d_parent) != dir)
944 return -EINVAL;
945 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
946
947 error = inode_permission(idmap, dir, MAY_WRITE | MAY_EXEC);
948 if (error)
949 return error;
950 if (IS_APPEND(dir))
951 return -EPERM;
952 if (check_sticky(idmap, dir, d_inode(victim)) ||
953 IS_APPEND(d_inode(victim)) || IS_IMMUTABLE(d_inode(victim)) ||
954 IS_SWAPFILE(d_inode(victim)))
955 return -EPERM;
956 if (isdir) {
957 if (!d_is_dir(victim))
958 return -ENOTDIR;
959 if (IS_ROOT(victim))
960 return -EBUSY;
961 } else if (d_is_dir(victim))
962 return -EISDIR;
963 if (IS_DEADDIR(dir))
964 return -ENOENT;
965 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
966 return -EBUSY;
967 return 0;
968}
969
970/* copy of may_create in fs/namei.c() */
971static inline int btrfs_may_create(struct mnt_idmap *idmap,
972 struct inode *dir, struct dentry *child)
973{
974 if (d_really_is_positive(child))
975 return -EEXIST;
976 if (IS_DEADDIR(dir))
977 return -ENOENT;
978 if (!fsuidgid_has_mapping(dir->i_sb, idmap))
979 return -EOVERFLOW;
980 return inode_permission(idmap, dir, MAY_WRITE | MAY_EXEC);
981}
982
983/*
984 * Create a new subvolume below @parent. This is largely modeled after
985 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
986 * inside this filesystem so it's quite a bit simpler.
987 */
988static noinline int btrfs_mksubvol(const struct path *parent,
989 struct mnt_idmap *idmap,
990 const char *name, int namelen,
991 struct btrfs_root *snap_src,
992 bool readonly,
993 struct btrfs_qgroup_inherit *inherit)
994{
995 struct inode *dir = d_inode(parent->dentry);
996 struct btrfs_fs_info *fs_info = inode_to_fs_info(dir);
997 struct dentry *dentry;
998 struct fscrypt_str name_str = FSTR_INIT((char *)name, namelen);
999 int error;
1000
1001 error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
1002 if (error == -EINTR)
1003 return error;
1004
1005 dentry = lookup_one(idmap, name, parent->dentry, namelen);
1006 error = PTR_ERR(dentry);
1007 if (IS_ERR(dentry))
1008 goto out_unlock;
1009
1010 error = btrfs_may_create(idmap, dir, dentry);
1011 if (error)
1012 goto out_dput;
1013
1014 /*
1015 * even if this name doesn't exist, we may get hash collisions.
1016 * check for them now when we can safely fail
1017 */
1018 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
1019 dir->i_ino, &name_str);
1020 if (error)
1021 goto out_dput;
1022
1023 down_read(&fs_info->subvol_sem);
1024
1025 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
1026 goto out_up_read;
1027
1028 if (snap_src)
1029 error = create_snapshot(snap_src, dir, dentry, readonly, inherit);
1030 else
1031 error = create_subvol(idmap, dir, dentry, inherit);
1032
1033 if (!error)
1034 fsnotify_mkdir(dir, dentry);
1035out_up_read:
1036 up_read(&fs_info->subvol_sem);
1037out_dput:
1038 dput(dentry);
1039out_unlock:
1040 btrfs_inode_unlock(BTRFS_I(dir), 0);
1041 return error;
1042}
1043
1044static noinline int btrfs_mksnapshot(const struct path *parent,
1045 struct mnt_idmap *idmap,
1046 const char *name, int namelen,
1047 struct btrfs_root *root,
1048 bool readonly,
1049 struct btrfs_qgroup_inherit *inherit)
1050{
1051 int ret;
1052 bool snapshot_force_cow = false;
1053
1054 /*
1055 * Force new buffered writes to reserve space even when NOCOW is
1056 * possible. This is to avoid later writeback (running dealloc) to
1057 * fallback to COW mode and unexpectedly fail with ENOSPC.
1058 */
1059 btrfs_drew_read_lock(&root->snapshot_lock);
1060
1061 ret = btrfs_start_delalloc_snapshot(root, false);
1062 if (ret)
1063 goto out;
1064
1065 /*
1066 * All previous writes have started writeback in NOCOW mode, so now
1067 * we force future writes to fallback to COW mode during snapshot
1068 * creation.
1069 */
1070 atomic_inc(&root->snapshot_force_cow);
1071 snapshot_force_cow = true;
1072
1073 btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
1074
1075 ret = btrfs_mksubvol(parent, idmap, name, namelen,
1076 root, readonly, inherit);
1077out:
1078 if (snapshot_force_cow)
1079 atomic_dec(&root->snapshot_force_cow);
1080 btrfs_drew_read_unlock(&root->snapshot_lock);
1081 return ret;
1082}
1083
1084/*
1085 * Try to start exclusive operation @type or cancel it if it's running.
1086 *
1087 * Return:
1088 * 0 - normal mode, newly claimed op started
1089 * >0 - normal mode, something else is running,
1090 * return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS to user space
1091 * ECANCELED - cancel mode, successful cancel
1092 * ENOTCONN - cancel mode, operation not running anymore
1093 */
1094static int exclop_start_or_cancel_reloc(struct btrfs_fs_info *fs_info,
1095 enum btrfs_exclusive_operation type, bool cancel)
1096{
1097 if (!cancel) {
1098 /* Start normal op */
1099 if (!btrfs_exclop_start(fs_info, type))
1100 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1101 /* Exclusive operation is now claimed */
1102 return 0;
1103 }
1104
1105 /* Cancel running op */
1106 if (btrfs_exclop_start_try_lock(fs_info, type)) {
1107 /*
1108 * This blocks any exclop finish from setting it to NONE, so we
1109 * request cancellation. Either it runs and we will wait for it,
1110 * or it has finished and no waiting will happen.
1111 */
1112 atomic_inc(&fs_info->reloc_cancel_req);
1113 btrfs_exclop_start_unlock(fs_info);
1114
1115 if (test_bit(BTRFS_FS_RELOC_RUNNING, &fs_info->flags))
1116 wait_on_bit(&fs_info->flags, BTRFS_FS_RELOC_RUNNING,
1117 TASK_INTERRUPTIBLE);
1118
1119 return -ECANCELED;
1120 }
1121
1122 /* Something else is running or none */
1123 return -ENOTCONN;
1124}
1125
1126static noinline int btrfs_ioctl_resize(struct file *file,
1127 void __user *arg)
1128{
1129 BTRFS_DEV_LOOKUP_ARGS(args);
1130 struct inode *inode = file_inode(file);
1131 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
1132 u64 new_size;
1133 u64 old_size;
1134 u64 devid = 1;
1135 struct btrfs_root *root = BTRFS_I(inode)->root;
1136 struct btrfs_ioctl_vol_args *vol_args;
1137 struct btrfs_trans_handle *trans;
1138 struct btrfs_device *device = NULL;
1139 char *sizestr;
1140 char *retptr;
1141 char *devstr = NULL;
1142 int ret = 0;
1143 int mod = 0;
1144 bool cancel;
1145
1146 if (!capable(CAP_SYS_ADMIN))
1147 return -EPERM;
1148
1149 ret = mnt_want_write_file(file);
1150 if (ret)
1151 return ret;
1152
1153 /*
1154 * Read the arguments before checking exclusivity to be able to
1155 * distinguish regular resize and cancel
1156 */
1157 vol_args = memdup_user(arg, sizeof(*vol_args));
1158 if (IS_ERR(vol_args)) {
1159 ret = PTR_ERR(vol_args);
1160 goto out_drop;
1161 }
1162 ret = btrfs_check_ioctl_vol_args_path(vol_args);
1163 if (ret < 0)
1164 goto out_free;
1165
1166 sizestr = vol_args->name;
1167 cancel = (strcmp("cancel", sizestr) == 0);
1168 ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_RESIZE, cancel);
1169 if (ret)
1170 goto out_free;
1171 /* Exclusive operation is now claimed */
1172
1173 devstr = strchr(sizestr, ':');
1174 if (devstr) {
1175 sizestr = devstr + 1;
1176 *devstr = '\0';
1177 devstr = vol_args->name;
1178 ret = kstrtoull(devstr, 10, &devid);
1179 if (ret)
1180 goto out_finish;
1181 if (!devid) {
1182 ret = -EINVAL;
1183 goto out_finish;
1184 }
1185 btrfs_info(fs_info, "resizing devid %llu", devid);
1186 }
1187
1188 args.devid = devid;
1189 device = btrfs_find_device(fs_info->fs_devices, &args);
1190 if (!device) {
1191 btrfs_info(fs_info, "resizer unable to find device %llu",
1192 devid);
1193 ret = -ENODEV;
1194 goto out_finish;
1195 }
1196
1197 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
1198 btrfs_info(fs_info,
1199 "resizer unable to apply on readonly device %llu",
1200 devid);
1201 ret = -EPERM;
1202 goto out_finish;
1203 }
1204
1205 if (!strcmp(sizestr, "max"))
1206 new_size = bdev_nr_bytes(device->bdev);
1207 else {
1208 if (sizestr[0] == '-') {
1209 mod = -1;
1210 sizestr++;
1211 } else if (sizestr[0] == '+') {
1212 mod = 1;
1213 sizestr++;
1214 }
1215 new_size = memparse(sizestr, &retptr);
1216 if (*retptr != '\0' || new_size == 0) {
1217 ret = -EINVAL;
1218 goto out_finish;
1219 }
1220 }
1221
1222 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
1223 ret = -EPERM;
1224 goto out_finish;
1225 }
1226
1227 old_size = btrfs_device_get_total_bytes(device);
1228
1229 if (mod < 0) {
1230 if (new_size > old_size) {
1231 ret = -EINVAL;
1232 goto out_finish;
1233 }
1234 new_size = old_size - new_size;
1235 } else if (mod > 0) {
1236 if (new_size > ULLONG_MAX - old_size) {
1237 ret = -ERANGE;
1238 goto out_finish;
1239 }
1240 new_size = old_size + new_size;
1241 }
1242
1243 if (new_size < SZ_256M) {
1244 ret = -EINVAL;
1245 goto out_finish;
1246 }
1247 if (new_size > bdev_nr_bytes(device->bdev)) {
1248 ret = -EFBIG;
1249 goto out_finish;
1250 }
1251
1252 new_size = round_down(new_size, fs_info->sectorsize);
1253
1254 if (new_size > old_size) {
1255 trans = btrfs_start_transaction(root, 0);
1256 if (IS_ERR(trans)) {
1257 ret = PTR_ERR(trans);
1258 goto out_finish;
1259 }
1260 ret = btrfs_grow_device(trans, device, new_size);
1261 btrfs_commit_transaction(trans);
1262 } else if (new_size < old_size) {
1263 ret = btrfs_shrink_device(device, new_size);
1264 } /* equal, nothing need to do */
1265
1266 if (ret == 0 && new_size != old_size)
1267 btrfs_info_in_rcu(fs_info,
1268 "resize device %s (devid %llu) from %llu to %llu",
1269 btrfs_dev_name(device), device->devid,
1270 old_size, new_size);
1271out_finish:
1272 btrfs_exclop_finish(fs_info);
1273out_free:
1274 kfree(vol_args);
1275out_drop:
1276 mnt_drop_write_file(file);
1277 return ret;
1278}
1279
1280static noinline int __btrfs_ioctl_snap_create(struct file *file,
1281 struct mnt_idmap *idmap,
1282 const char *name, unsigned long fd, int subvol,
1283 bool readonly,
1284 struct btrfs_qgroup_inherit *inherit)
1285{
1286 int namelen;
1287 int ret = 0;
1288
1289 if (!S_ISDIR(file_inode(file)->i_mode))
1290 return -ENOTDIR;
1291
1292 ret = mnt_want_write_file(file);
1293 if (ret)
1294 goto out;
1295
1296 namelen = strlen(name);
1297 if (strchr(name, '/')) {
1298 ret = -EINVAL;
1299 goto out_drop_write;
1300 }
1301
1302 if (name[0] == '.' &&
1303 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1304 ret = -EEXIST;
1305 goto out_drop_write;
1306 }
1307
1308 if (subvol) {
1309 ret = btrfs_mksubvol(&file->f_path, idmap, name,
1310 namelen, NULL, readonly, inherit);
1311 } else {
1312 struct fd src = fdget(fd);
1313 struct inode *src_inode;
1314 if (!src.file) {
1315 ret = -EINVAL;
1316 goto out_drop_write;
1317 }
1318
1319 src_inode = file_inode(src.file);
1320 if (src_inode->i_sb != file_inode(file)->i_sb) {
1321 btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
1322 "Snapshot src from another FS");
1323 ret = -EXDEV;
1324 } else if (!inode_owner_or_capable(idmap, src_inode)) {
1325 /*
1326 * Subvolume creation is not restricted, but snapshots
1327 * are limited to own subvolumes only
1328 */
1329 ret = -EPERM;
1330 } else if (btrfs_ino(BTRFS_I(src_inode)) != BTRFS_FIRST_FREE_OBJECTID) {
1331 /*
1332 * Snapshots must be made with the src_inode referring
1333 * to the subvolume inode, otherwise the permission
1334 * checking above is useless because we may have
1335 * permission on a lower directory but not the subvol
1336 * itself.
1337 */
1338 ret = -EINVAL;
1339 } else {
1340 ret = btrfs_mksnapshot(&file->f_path, idmap,
1341 name, namelen,
1342 BTRFS_I(src_inode)->root,
1343 readonly, inherit);
1344 }
1345 fdput(src);
1346 }
1347out_drop_write:
1348 mnt_drop_write_file(file);
1349out:
1350 return ret;
1351}
1352
1353static noinline int btrfs_ioctl_snap_create(struct file *file,
1354 void __user *arg, int subvol)
1355{
1356 struct btrfs_ioctl_vol_args *vol_args;
1357 int ret;
1358
1359 if (!S_ISDIR(file_inode(file)->i_mode))
1360 return -ENOTDIR;
1361
1362 vol_args = memdup_user(arg, sizeof(*vol_args));
1363 if (IS_ERR(vol_args))
1364 return PTR_ERR(vol_args);
1365 ret = btrfs_check_ioctl_vol_args_path(vol_args);
1366 if (ret < 0)
1367 goto out;
1368
1369 ret = __btrfs_ioctl_snap_create(file, file_mnt_idmap(file),
1370 vol_args->name, vol_args->fd, subvol,
1371 false, NULL);
1372
1373out:
1374 kfree(vol_args);
1375 return ret;
1376}
1377
1378static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1379 void __user *arg, int subvol)
1380{
1381 struct btrfs_ioctl_vol_args_v2 *vol_args;
1382 int ret;
1383 bool readonly = false;
1384 struct btrfs_qgroup_inherit *inherit = NULL;
1385
1386 if (!S_ISDIR(file_inode(file)->i_mode))
1387 return -ENOTDIR;
1388
1389 vol_args = memdup_user(arg, sizeof(*vol_args));
1390 if (IS_ERR(vol_args))
1391 return PTR_ERR(vol_args);
1392 ret = btrfs_check_ioctl_vol_args2_subvol_name(vol_args);
1393 if (ret < 0)
1394 goto free_args;
1395
1396 if (vol_args->flags & ~BTRFS_SUBVOL_CREATE_ARGS_MASK) {
1397 ret = -EOPNOTSUPP;
1398 goto free_args;
1399 }
1400
1401 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1402 readonly = true;
1403 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1404 struct btrfs_fs_info *fs_info = inode_to_fs_info(file_inode(file));
1405
1406 if (vol_args->size < sizeof(*inherit) ||
1407 vol_args->size > PAGE_SIZE) {
1408 ret = -EINVAL;
1409 goto free_args;
1410 }
1411 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1412 if (IS_ERR(inherit)) {
1413 ret = PTR_ERR(inherit);
1414 goto free_args;
1415 }
1416
1417 ret = btrfs_qgroup_check_inherit(fs_info, inherit, vol_args->size);
1418 if (ret < 0)
1419 goto free_inherit;
1420 }
1421
1422 ret = __btrfs_ioctl_snap_create(file, file_mnt_idmap(file),
1423 vol_args->name, vol_args->fd, subvol,
1424 readonly, inherit);
1425 if (ret)
1426 goto free_inherit;
1427free_inherit:
1428 kfree(inherit);
1429free_args:
1430 kfree(vol_args);
1431 return ret;
1432}
1433
1434static noinline int btrfs_ioctl_subvol_getflags(struct inode *inode,
1435 void __user *arg)
1436{
1437 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
1438 struct btrfs_root *root = BTRFS_I(inode)->root;
1439 int ret = 0;
1440 u64 flags = 0;
1441
1442 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)
1443 return -EINVAL;
1444
1445 down_read(&fs_info->subvol_sem);
1446 if (btrfs_root_readonly(root))
1447 flags |= BTRFS_SUBVOL_RDONLY;
1448 up_read(&fs_info->subvol_sem);
1449
1450 if (copy_to_user(arg, &flags, sizeof(flags)))
1451 ret = -EFAULT;
1452
1453 return ret;
1454}
1455
1456static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1457 void __user *arg)
1458{
1459 struct inode *inode = file_inode(file);
1460 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
1461 struct btrfs_root *root = BTRFS_I(inode)->root;
1462 struct btrfs_trans_handle *trans;
1463 u64 root_flags;
1464 u64 flags;
1465 int ret = 0;
1466
1467 if (!inode_owner_or_capable(file_mnt_idmap(file), inode))
1468 return -EPERM;
1469
1470 ret = mnt_want_write_file(file);
1471 if (ret)
1472 goto out;
1473
1474 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
1475 ret = -EINVAL;
1476 goto out_drop_write;
1477 }
1478
1479 if (copy_from_user(&flags, arg, sizeof(flags))) {
1480 ret = -EFAULT;
1481 goto out_drop_write;
1482 }
1483
1484 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1485 ret = -EOPNOTSUPP;
1486 goto out_drop_write;
1487 }
1488
1489 down_write(&fs_info->subvol_sem);
1490
1491 /* nothing to do */
1492 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1493 goto out_drop_sem;
1494
1495 root_flags = btrfs_root_flags(&root->root_item);
1496 if (flags & BTRFS_SUBVOL_RDONLY) {
1497 btrfs_set_root_flags(&root->root_item,
1498 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1499 } else {
1500 /*
1501 * Block RO -> RW transition if this subvolume is involved in
1502 * send
1503 */
1504 spin_lock(&root->root_item_lock);
1505 if (root->send_in_progress == 0) {
1506 btrfs_set_root_flags(&root->root_item,
1507 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1508 spin_unlock(&root->root_item_lock);
1509 } else {
1510 spin_unlock(&root->root_item_lock);
1511 btrfs_warn(fs_info,
1512 "Attempt to set subvolume %llu read-write during send",
1513 root->root_key.objectid);
1514 ret = -EPERM;
1515 goto out_drop_sem;
1516 }
1517 }
1518
1519 trans = btrfs_start_transaction(root, 1);
1520 if (IS_ERR(trans)) {
1521 ret = PTR_ERR(trans);
1522 goto out_reset;
1523 }
1524
1525 ret = btrfs_update_root(trans, fs_info->tree_root,
1526 &root->root_key, &root->root_item);
1527 if (ret < 0) {
1528 btrfs_end_transaction(trans);
1529 goto out_reset;
1530 }
1531
1532 ret = btrfs_commit_transaction(trans);
1533
1534out_reset:
1535 if (ret)
1536 btrfs_set_root_flags(&root->root_item, root_flags);
1537out_drop_sem:
1538 up_write(&fs_info->subvol_sem);
1539out_drop_write:
1540 mnt_drop_write_file(file);
1541out:
1542 return ret;
1543}
1544
1545static noinline int key_in_sk(struct btrfs_key *key,
1546 struct btrfs_ioctl_search_key *sk)
1547{
1548 struct btrfs_key test;
1549 int ret;
1550
1551 test.objectid = sk->min_objectid;
1552 test.type = sk->min_type;
1553 test.offset = sk->min_offset;
1554
1555 ret = btrfs_comp_cpu_keys(key, &test);
1556 if (ret < 0)
1557 return 0;
1558
1559 test.objectid = sk->max_objectid;
1560 test.type = sk->max_type;
1561 test.offset = sk->max_offset;
1562
1563 ret = btrfs_comp_cpu_keys(key, &test);
1564 if (ret > 0)
1565 return 0;
1566 return 1;
1567}
1568
1569static noinline int copy_to_sk(struct btrfs_path *path,
1570 struct btrfs_key *key,
1571 struct btrfs_ioctl_search_key *sk,
1572 u64 *buf_size,
1573 char __user *ubuf,
1574 unsigned long *sk_offset,
1575 int *num_found)
1576{
1577 u64 found_transid;
1578 struct extent_buffer *leaf;
1579 struct btrfs_ioctl_search_header sh;
1580 struct btrfs_key test;
1581 unsigned long item_off;
1582 unsigned long item_len;
1583 int nritems;
1584 int i;
1585 int slot;
1586 int ret = 0;
1587
1588 leaf = path->nodes[0];
1589 slot = path->slots[0];
1590 nritems = btrfs_header_nritems(leaf);
1591
1592 if (btrfs_header_generation(leaf) > sk->max_transid) {
1593 i = nritems;
1594 goto advance_key;
1595 }
1596 found_transid = btrfs_header_generation(leaf);
1597
1598 for (i = slot; i < nritems; i++) {
1599 item_off = btrfs_item_ptr_offset(leaf, i);
1600 item_len = btrfs_item_size(leaf, i);
1601
1602 btrfs_item_key_to_cpu(leaf, key, i);
1603 if (!key_in_sk(key, sk))
1604 continue;
1605
1606 if (sizeof(sh) + item_len > *buf_size) {
1607 if (*num_found) {
1608 ret = 1;
1609 goto out;
1610 }
1611
1612 /*
1613 * return one empty item back for v1, which does not
1614 * handle -EOVERFLOW
1615 */
1616
1617 *buf_size = sizeof(sh) + item_len;
1618 item_len = 0;
1619 ret = -EOVERFLOW;
1620 }
1621
1622 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
1623 ret = 1;
1624 goto out;
1625 }
1626
1627 sh.objectid = key->objectid;
1628 sh.offset = key->offset;
1629 sh.type = key->type;
1630 sh.len = item_len;
1631 sh.transid = found_transid;
1632
1633 /*
1634 * Copy search result header. If we fault then loop again so we
1635 * can fault in the pages and -EFAULT there if there's a
1636 * problem. Otherwise we'll fault and then copy the buffer in
1637 * properly this next time through
1638 */
1639 if (copy_to_user_nofault(ubuf + *sk_offset, &sh, sizeof(sh))) {
1640 ret = 0;
1641 goto out;
1642 }
1643
1644 *sk_offset += sizeof(sh);
1645
1646 if (item_len) {
1647 char __user *up = ubuf + *sk_offset;
1648 /*
1649 * Copy the item, same behavior as above, but reset the
1650 * * sk_offset so we copy the full thing again.
1651 */
1652 if (read_extent_buffer_to_user_nofault(leaf, up,
1653 item_off, item_len)) {
1654 ret = 0;
1655 *sk_offset -= sizeof(sh);
1656 goto out;
1657 }
1658
1659 *sk_offset += item_len;
1660 }
1661 (*num_found)++;
1662
1663 if (ret) /* -EOVERFLOW from above */
1664 goto out;
1665
1666 if (*num_found >= sk->nr_items) {
1667 ret = 1;
1668 goto out;
1669 }
1670 }
1671advance_key:
1672 ret = 0;
1673 test.objectid = sk->max_objectid;
1674 test.type = sk->max_type;
1675 test.offset = sk->max_offset;
1676 if (btrfs_comp_cpu_keys(key, &test) >= 0)
1677 ret = 1;
1678 else if (key->offset < (u64)-1)
1679 key->offset++;
1680 else if (key->type < (u8)-1) {
1681 key->offset = 0;
1682 key->type++;
1683 } else if (key->objectid < (u64)-1) {
1684 key->offset = 0;
1685 key->type = 0;
1686 key->objectid++;
1687 } else
1688 ret = 1;
1689out:
1690 /*
1691 * 0: all items from this leaf copied, continue with next
1692 * 1: * more items can be copied, but unused buffer is too small
1693 * * all items were found
1694 * Either way, it will stops the loop which iterates to the next
1695 * leaf
1696 * -EOVERFLOW: item was to large for buffer
1697 * -EFAULT: could not copy extent buffer back to userspace
1698 */
1699 return ret;
1700}
1701
1702static noinline int search_ioctl(struct inode *inode,
1703 struct btrfs_ioctl_search_key *sk,
1704 u64 *buf_size,
1705 char __user *ubuf)
1706{
1707 struct btrfs_fs_info *info = inode_to_fs_info(inode);
1708 struct btrfs_root *root;
1709 struct btrfs_key key;
1710 struct btrfs_path *path;
1711 int ret;
1712 int num_found = 0;
1713 unsigned long sk_offset = 0;
1714
1715 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
1716 *buf_size = sizeof(struct btrfs_ioctl_search_header);
1717 return -EOVERFLOW;
1718 }
1719
1720 path = btrfs_alloc_path();
1721 if (!path)
1722 return -ENOMEM;
1723
1724 if (sk->tree_id == 0) {
1725 /* search the root of the inode that was passed */
1726 root = btrfs_grab_root(BTRFS_I(inode)->root);
1727 } else {
1728 root = btrfs_get_fs_root(info, sk->tree_id, true);
1729 if (IS_ERR(root)) {
1730 btrfs_free_path(path);
1731 return PTR_ERR(root);
1732 }
1733 }
1734
1735 key.objectid = sk->min_objectid;
1736 key.type = sk->min_type;
1737 key.offset = sk->min_offset;
1738
1739 while (1) {
1740 ret = -EFAULT;
1741 /*
1742 * Ensure that the whole user buffer is faulted in at sub-page
1743 * granularity, otherwise the loop may live-lock.
1744 */
1745 if (fault_in_subpage_writeable(ubuf + sk_offset,
1746 *buf_size - sk_offset))
1747 break;
1748
1749 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
1750 if (ret != 0) {
1751 if (ret > 0)
1752 ret = 0;
1753 goto err;
1754 }
1755 ret = copy_to_sk(path, &key, sk, buf_size, ubuf,
1756 &sk_offset, &num_found);
1757 btrfs_release_path(path);
1758 if (ret)
1759 break;
1760
1761 }
1762 if (ret > 0)
1763 ret = 0;
1764err:
1765 sk->nr_items = num_found;
1766 btrfs_put_root(root);
1767 btrfs_free_path(path);
1768 return ret;
1769}
1770
1771static noinline int btrfs_ioctl_tree_search(struct inode *inode,
1772 void __user *argp)
1773{
1774 struct btrfs_ioctl_search_args __user *uargs = argp;
1775 struct btrfs_ioctl_search_key sk;
1776 int ret;
1777 u64 buf_size;
1778
1779 if (!capable(CAP_SYS_ADMIN))
1780 return -EPERM;
1781
1782 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
1783 return -EFAULT;
1784
1785 buf_size = sizeof(uargs->buf);
1786
1787 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
1788
1789 /*
1790 * In the origin implementation an overflow is handled by returning a
1791 * search header with a len of zero, so reset ret.
1792 */
1793 if (ret == -EOVERFLOW)
1794 ret = 0;
1795
1796 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
1797 ret = -EFAULT;
1798 return ret;
1799}
1800
1801static noinline int btrfs_ioctl_tree_search_v2(struct inode *inode,
1802 void __user *argp)
1803{
1804 struct btrfs_ioctl_search_args_v2 __user *uarg = argp;
1805 struct btrfs_ioctl_search_args_v2 args;
1806 int ret;
1807 u64 buf_size;
1808 const u64 buf_limit = SZ_16M;
1809
1810 if (!capable(CAP_SYS_ADMIN))
1811 return -EPERM;
1812
1813 /* copy search header and buffer size */
1814 if (copy_from_user(&args, uarg, sizeof(args)))
1815 return -EFAULT;
1816
1817 buf_size = args.buf_size;
1818
1819 /* limit result size to 16MB */
1820 if (buf_size > buf_limit)
1821 buf_size = buf_limit;
1822
1823 ret = search_ioctl(inode, &args.key, &buf_size,
1824 (char __user *)(&uarg->buf[0]));
1825 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
1826 ret = -EFAULT;
1827 else if (ret == -EOVERFLOW &&
1828 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
1829 ret = -EFAULT;
1830
1831 return ret;
1832}
1833
1834/*
1835 * Search INODE_REFs to identify path name of 'dirid' directory
1836 * in a 'tree_id' tree. and sets path name to 'name'.
1837 */
1838static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1839 u64 tree_id, u64 dirid, char *name)
1840{
1841 struct btrfs_root *root;
1842 struct btrfs_key key;
1843 char *ptr;
1844 int ret = -1;
1845 int slot;
1846 int len;
1847 int total_len = 0;
1848 struct btrfs_inode_ref *iref;
1849 struct extent_buffer *l;
1850 struct btrfs_path *path;
1851
1852 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1853 name[0]='\0';
1854 return 0;
1855 }
1856
1857 path = btrfs_alloc_path();
1858 if (!path)
1859 return -ENOMEM;
1860
1861 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1];
1862
1863 root = btrfs_get_fs_root(info, tree_id, true);
1864 if (IS_ERR(root)) {
1865 ret = PTR_ERR(root);
1866 root = NULL;
1867 goto out;
1868 }
1869
1870 key.objectid = dirid;
1871 key.type = BTRFS_INODE_REF_KEY;
1872 key.offset = (u64)-1;
1873
1874 while (1) {
1875 ret = btrfs_search_backwards(root, &key, path);
1876 if (ret < 0)
1877 goto out;
1878 else if (ret > 0) {
1879 ret = -ENOENT;
1880 goto out;
1881 }
1882
1883 l = path->nodes[0];
1884 slot = path->slots[0];
1885
1886 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1887 len = btrfs_inode_ref_name_len(l, iref);
1888 ptr -= len + 1;
1889 total_len += len + 1;
1890 if (ptr < name) {
1891 ret = -ENAMETOOLONG;
1892 goto out;
1893 }
1894
1895 *(ptr + len) = '/';
1896 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
1897
1898 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1899 break;
1900
1901 btrfs_release_path(path);
1902 key.objectid = key.offset;
1903 key.offset = (u64)-1;
1904 dirid = key.objectid;
1905 }
1906 memmove(name, ptr, total_len);
1907 name[total_len] = '\0';
1908 ret = 0;
1909out:
1910 btrfs_put_root(root);
1911 btrfs_free_path(path);
1912 return ret;
1913}
1914
1915static int btrfs_search_path_in_tree_user(struct mnt_idmap *idmap,
1916 struct inode *inode,
1917 struct btrfs_ioctl_ino_lookup_user_args *args)
1918{
1919 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
1920 struct super_block *sb = inode->i_sb;
1921 struct btrfs_key upper_limit = BTRFS_I(inode)->location;
1922 u64 treeid = BTRFS_I(inode)->root->root_key.objectid;
1923 u64 dirid = args->dirid;
1924 unsigned long item_off;
1925 unsigned long item_len;
1926 struct btrfs_inode_ref *iref;
1927 struct btrfs_root_ref *rref;
1928 struct btrfs_root *root = NULL;
1929 struct btrfs_path *path;
1930 struct btrfs_key key, key2;
1931 struct extent_buffer *leaf;
1932 struct inode *temp_inode;
1933 char *ptr;
1934 int slot;
1935 int len;
1936 int total_len = 0;
1937 int ret;
1938
1939 path = btrfs_alloc_path();
1940 if (!path)
1941 return -ENOMEM;
1942
1943 /*
1944 * If the bottom subvolume does not exist directly under upper_limit,
1945 * construct the path in from the bottom up.
1946 */
1947 if (dirid != upper_limit.objectid) {
1948 ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1];
1949
1950 root = btrfs_get_fs_root(fs_info, treeid, true);
1951 if (IS_ERR(root)) {
1952 ret = PTR_ERR(root);
1953 goto out;
1954 }
1955
1956 key.objectid = dirid;
1957 key.type = BTRFS_INODE_REF_KEY;
1958 key.offset = (u64)-1;
1959 while (1) {
1960 ret = btrfs_search_backwards(root, &key, path);
1961 if (ret < 0)
1962 goto out_put;
1963 else if (ret > 0) {
1964 ret = -ENOENT;
1965 goto out_put;
1966 }
1967
1968 leaf = path->nodes[0];
1969 slot = path->slots[0];
1970
1971 iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref);
1972 len = btrfs_inode_ref_name_len(leaf, iref);
1973 ptr -= len + 1;
1974 total_len += len + 1;
1975 if (ptr < args->path) {
1976 ret = -ENAMETOOLONG;
1977 goto out_put;
1978 }
1979
1980 *(ptr + len) = '/';
1981 read_extent_buffer(leaf, ptr,
1982 (unsigned long)(iref + 1), len);
1983
1984 /* Check the read+exec permission of this directory */
1985 ret = btrfs_previous_item(root, path, dirid,
1986 BTRFS_INODE_ITEM_KEY);
1987 if (ret < 0) {
1988 goto out_put;
1989 } else if (ret > 0) {
1990 ret = -ENOENT;
1991 goto out_put;
1992 }
1993
1994 leaf = path->nodes[0];
1995 slot = path->slots[0];
1996 btrfs_item_key_to_cpu(leaf, &key2, slot);
1997 if (key2.objectid != dirid) {
1998 ret = -ENOENT;
1999 goto out_put;
2000 }
2001
2002 /*
2003 * We don't need the path anymore, so release it and
2004 * avoid deadlocks and lockdep warnings in case
2005 * btrfs_iget() needs to lookup the inode from its root
2006 * btree and lock the same leaf.
2007 */
2008 btrfs_release_path(path);
2009 temp_inode = btrfs_iget(sb, key2.objectid, root);
2010 if (IS_ERR(temp_inode)) {
2011 ret = PTR_ERR(temp_inode);
2012 goto out_put;
2013 }
2014 ret = inode_permission(idmap, temp_inode,
2015 MAY_READ | MAY_EXEC);
2016 iput(temp_inode);
2017 if (ret) {
2018 ret = -EACCES;
2019 goto out_put;
2020 }
2021
2022 if (key.offset == upper_limit.objectid)
2023 break;
2024 if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {
2025 ret = -EACCES;
2026 goto out_put;
2027 }
2028
2029 key.objectid = key.offset;
2030 key.offset = (u64)-1;
2031 dirid = key.objectid;
2032 }
2033
2034 memmove(args->path, ptr, total_len);
2035 args->path[total_len] = '\0';
2036 btrfs_put_root(root);
2037 root = NULL;
2038 btrfs_release_path(path);
2039 }
2040
2041 /* Get the bottom subvolume's name from ROOT_REF */
2042 key.objectid = treeid;
2043 key.type = BTRFS_ROOT_REF_KEY;
2044 key.offset = args->treeid;
2045 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
2046 if (ret < 0) {
2047 goto out;
2048 } else if (ret > 0) {
2049 ret = -ENOENT;
2050 goto out;
2051 }
2052
2053 leaf = path->nodes[0];
2054 slot = path->slots[0];
2055 btrfs_item_key_to_cpu(leaf, &key, slot);
2056
2057 item_off = btrfs_item_ptr_offset(leaf, slot);
2058 item_len = btrfs_item_size(leaf, slot);
2059 /* Check if dirid in ROOT_REF corresponds to passed dirid */
2060 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2061 if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) {
2062 ret = -EINVAL;
2063 goto out;
2064 }
2065
2066 /* Copy subvolume's name */
2067 item_off += sizeof(struct btrfs_root_ref);
2068 item_len -= sizeof(struct btrfs_root_ref);
2069 read_extent_buffer(leaf, args->name, item_off, item_len);
2070 args->name[item_len] = 0;
2071
2072out_put:
2073 btrfs_put_root(root);
2074out:
2075 btrfs_free_path(path);
2076 return ret;
2077}
2078
2079static noinline int btrfs_ioctl_ino_lookup(struct btrfs_root *root,
2080 void __user *argp)
2081{
2082 struct btrfs_ioctl_ino_lookup_args *args;
2083 int ret = 0;
2084
2085 args = memdup_user(argp, sizeof(*args));
2086 if (IS_ERR(args))
2087 return PTR_ERR(args);
2088
2089 /*
2090 * Unprivileged query to obtain the containing subvolume root id. The
2091 * path is reset so it's consistent with btrfs_search_path_in_tree.
2092 */
2093 if (args->treeid == 0)
2094 args->treeid = root->root_key.objectid;
2095
2096 if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2097 args->name[0] = 0;
2098 goto out;
2099 }
2100
2101 if (!capable(CAP_SYS_ADMIN)) {
2102 ret = -EPERM;
2103 goto out;
2104 }
2105
2106 ret = btrfs_search_path_in_tree(root->fs_info,
2107 args->treeid, args->objectid,
2108 args->name);
2109
2110out:
2111 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2112 ret = -EFAULT;
2113
2114 kfree(args);
2115 return ret;
2116}
2117
2118/*
2119 * Version of ino_lookup ioctl (unprivileged)
2120 *
2121 * The main differences from ino_lookup ioctl are:
2122 *
2123 * 1. Read + Exec permission will be checked using inode_permission() during
2124 * path construction. -EACCES will be returned in case of failure.
2125 * 2. Path construction will be stopped at the inode number which corresponds
2126 * to the fd with which this ioctl is called. If constructed path does not
2127 * exist under fd's inode, -EACCES will be returned.
2128 * 3. The name of bottom subvolume is also searched and filled.
2129 */
2130static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp)
2131{
2132 struct btrfs_ioctl_ino_lookup_user_args *args;
2133 struct inode *inode;
2134 int ret;
2135
2136 args = memdup_user(argp, sizeof(*args));
2137 if (IS_ERR(args))
2138 return PTR_ERR(args);
2139
2140 inode = file_inode(file);
2141
2142 if (args->dirid == BTRFS_FIRST_FREE_OBJECTID &&
2143 BTRFS_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) {
2144 /*
2145 * The subvolume does not exist under fd with which this is
2146 * called
2147 */
2148 kfree(args);
2149 return -EACCES;
2150 }
2151
2152 ret = btrfs_search_path_in_tree_user(file_mnt_idmap(file), inode, args);
2153
2154 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2155 ret = -EFAULT;
2156
2157 kfree(args);
2158 return ret;
2159}
2160
2161/* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */
2162static int btrfs_ioctl_get_subvol_info(struct inode *inode, void __user *argp)
2163{
2164 struct btrfs_ioctl_get_subvol_info_args *subvol_info;
2165 struct btrfs_fs_info *fs_info;
2166 struct btrfs_root *root;
2167 struct btrfs_path *path;
2168 struct btrfs_key key;
2169 struct btrfs_root_item *root_item;
2170 struct btrfs_root_ref *rref;
2171 struct extent_buffer *leaf;
2172 unsigned long item_off;
2173 unsigned long item_len;
2174 int slot;
2175 int ret = 0;
2176
2177 path = btrfs_alloc_path();
2178 if (!path)
2179 return -ENOMEM;
2180
2181 subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL);
2182 if (!subvol_info) {
2183 btrfs_free_path(path);
2184 return -ENOMEM;
2185 }
2186
2187 fs_info = BTRFS_I(inode)->root->fs_info;
2188
2189 /* Get root_item of inode's subvolume */
2190 key.objectid = BTRFS_I(inode)->root->root_key.objectid;
2191 root = btrfs_get_fs_root(fs_info, key.objectid, true);
2192 if (IS_ERR(root)) {
2193 ret = PTR_ERR(root);
2194 goto out_free;
2195 }
2196 root_item = &root->root_item;
2197
2198 subvol_info->treeid = key.objectid;
2199
2200 subvol_info->generation = btrfs_root_generation(root_item);
2201 subvol_info->flags = btrfs_root_flags(root_item);
2202
2203 memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE);
2204 memcpy(subvol_info->parent_uuid, root_item->parent_uuid,
2205 BTRFS_UUID_SIZE);
2206 memcpy(subvol_info->received_uuid, root_item->received_uuid,
2207 BTRFS_UUID_SIZE);
2208
2209 subvol_info->ctransid = btrfs_root_ctransid(root_item);
2210 subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime);
2211 subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime);
2212
2213 subvol_info->otransid = btrfs_root_otransid(root_item);
2214 subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime);
2215 subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime);
2216
2217 subvol_info->stransid = btrfs_root_stransid(root_item);
2218 subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime);
2219 subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime);
2220
2221 subvol_info->rtransid = btrfs_root_rtransid(root_item);
2222 subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime);
2223 subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime);
2224
2225 if (key.objectid != BTRFS_FS_TREE_OBJECTID) {
2226 /* Search root tree for ROOT_BACKREF of this subvolume */
2227 key.type = BTRFS_ROOT_BACKREF_KEY;
2228 key.offset = 0;
2229 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
2230 if (ret < 0) {
2231 goto out;
2232 } else if (path->slots[0] >=
2233 btrfs_header_nritems(path->nodes[0])) {
2234 ret = btrfs_next_leaf(fs_info->tree_root, path);
2235 if (ret < 0) {
2236 goto out;
2237 } else if (ret > 0) {
2238 ret = -EUCLEAN;
2239 goto out;
2240 }
2241 }
2242
2243 leaf = path->nodes[0];
2244 slot = path->slots[0];
2245 btrfs_item_key_to_cpu(leaf, &key, slot);
2246 if (key.objectid == subvol_info->treeid &&
2247 key.type == BTRFS_ROOT_BACKREF_KEY) {
2248 subvol_info->parent_id = key.offset;
2249
2250 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2251 subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref);
2252
2253 item_off = btrfs_item_ptr_offset(leaf, slot)
2254 + sizeof(struct btrfs_root_ref);
2255 item_len = btrfs_item_size(leaf, slot)
2256 - sizeof(struct btrfs_root_ref);
2257 read_extent_buffer(leaf, subvol_info->name,
2258 item_off, item_len);
2259 } else {
2260 ret = -ENOENT;
2261 goto out;
2262 }
2263 }
2264
2265 btrfs_free_path(path);
2266 path = NULL;
2267 if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))
2268 ret = -EFAULT;
2269
2270out:
2271 btrfs_put_root(root);
2272out_free:
2273 btrfs_free_path(path);
2274 kfree(subvol_info);
2275 return ret;
2276}
2277
2278/*
2279 * Return ROOT_REF information of the subvolume containing this inode
2280 * except the subvolume name.
2281 */
2282static int btrfs_ioctl_get_subvol_rootref(struct btrfs_root *root,
2283 void __user *argp)
2284{
2285 struct btrfs_ioctl_get_subvol_rootref_args *rootrefs;
2286 struct btrfs_root_ref *rref;
2287 struct btrfs_path *path;
2288 struct btrfs_key key;
2289 struct extent_buffer *leaf;
2290 u64 objectid;
2291 int slot;
2292 int ret;
2293 u8 found;
2294
2295 path = btrfs_alloc_path();
2296 if (!path)
2297 return -ENOMEM;
2298
2299 rootrefs = memdup_user(argp, sizeof(*rootrefs));
2300 if (IS_ERR(rootrefs)) {
2301 btrfs_free_path(path);
2302 return PTR_ERR(rootrefs);
2303 }
2304
2305 objectid = root->root_key.objectid;
2306 key.objectid = objectid;
2307 key.type = BTRFS_ROOT_REF_KEY;
2308 key.offset = rootrefs->min_treeid;
2309 found = 0;
2310
2311 root = root->fs_info->tree_root;
2312 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2313 if (ret < 0) {
2314 goto out;
2315 } else if (path->slots[0] >=
2316 btrfs_header_nritems(path->nodes[0])) {
2317 ret = btrfs_next_leaf(root, path);
2318 if (ret < 0) {
2319 goto out;
2320 } else if (ret > 0) {
2321 ret = -EUCLEAN;
2322 goto out;
2323 }
2324 }
2325 while (1) {
2326 leaf = path->nodes[0];
2327 slot = path->slots[0];
2328
2329 btrfs_item_key_to_cpu(leaf, &key, slot);
2330 if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) {
2331 ret = 0;
2332 goto out;
2333 }
2334
2335 if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) {
2336 ret = -EOVERFLOW;
2337 goto out;
2338 }
2339
2340 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2341 rootrefs->rootref[found].treeid = key.offset;
2342 rootrefs->rootref[found].dirid =
2343 btrfs_root_ref_dirid(leaf, rref);
2344 found++;
2345
2346 ret = btrfs_next_item(root, path);
2347 if (ret < 0) {
2348 goto out;
2349 } else if (ret > 0) {
2350 ret = -EUCLEAN;
2351 goto out;
2352 }
2353 }
2354
2355out:
2356 btrfs_free_path(path);
2357
2358 if (!ret || ret == -EOVERFLOW) {
2359 rootrefs->num_items = found;
2360 /* update min_treeid for next search */
2361 if (found)
2362 rootrefs->min_treeid =
2363 rootrefs->rootref[found - 1].treeid + 1;
2364 if (copy_to_user(argp, rootrefs, sizeof(*rootrefs)))
2365 ret = -EFAULT;
2366 }
2367
2368 kfree(rootrefs);
2369
2370 return ret;
2371}
2372
2373static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2374 void __user *arg,
2375 bool destroy_v2)
2376{
2377 struct dentry *parent = file->f_path.dentry;
2378 struct dentry *dentry;
2379 struct inode *dir = d_inode(parent);
2380 struct btrfs_fs_info *fs_info = inode_to_fs_info(dir);
2381 struct inode *inode;
2382 struct btrfs_root *root = BTRFS_I(dir)->root;
2383 struct btrfs_root *dest = NULL;
2384 struct btrfs_ioctl_vol_args *vol_args = NULL;
2385 struct btrfs_ioctl_vol_args_v2 *vol_args2 = NULL;
2386 struct mnt_idmap *idmap = file_mnt_idmap(file);
2387 char *subvol_name, *subvol_name_ptr = NULL;
2388 int subvol_namelen;
2389 int err = 0;
2390 bool destroy_parent = false;
2391
2392 /* We don't support snapshots with extent tree v2 yet. */
2393 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
2394 btrfs_err(fs_info,
2395 "extent tree v2 doesn't support snapshot deletion yet");
2396 return -EOPNOTSUPP;
2397 }
2398
2399 if (destroy_v2) {
2400 vol_args2 = memdup_user(arg, sizeof(*vol_args2));
2401 if (IS_ERR(vol_args2))
2402 return PTR_ERR(vol_args2);
2403
2404 if (vol_args2->flags & ~BTRFS_SUBVOL_DELETE_ARGS_MASK) {
2405 err = -EOPNOTSUPP;
2406 goto out;
2407 }
2408
2409 /*
2410 * If SPEC_BY_ID is not set, we are looking for the subvolume by
2411 * name, same as v1 currently does.
2412 */
2413 if (!(vol_args2->flags & BTRFS_SUBVOL_SPEC_BY_ID)) {
2414 err = btrfs_check_ioctl_vol_args2_subvol_name(vol_args2);
2415 if (err < 0)
2416 goto out;
2417 subvol_name = vol_args2->name;
2418
2419 err = mnt_want_write_file(file);
2420 if (err)
2421 goto out;
2422 } else {
2423 struct inode *old_dir;
2424
2425 if (vol_args2->subvolid < BTRFS_FIRST_FREE_OBJECTID) {
2426 err = -EINVAL;
2427 goto out;
2428 }
2429
2430 err = mnt_want_write_file(file);
2431 if (err)
2432 goto out;
2433
2434 dentry = btrfs_get_dentry(fs_info->sb,
2435 BTRFS_FIRST_FREE_OBJECTID,
2436 vol_args2->subvolid, 0);
2437 if (IS_ERR(dentry)) {
2438 err = PTR_ERR(dentry);
2439 goto out_drop_write;
2440 }
2441
2442 /*
2443 * Change the default parent since the subvolume being
2444 * deleted can be outside of the current mount point.
2445 */
2446 parent = btrfs_get_parent(dentry);
2447
2448 /*
2449 * At this point dentry->d_name can point to '/' if the
2450 * subvolume we want to destroy is outsite of the
2451 * current mount point, so we need to release the
2452 * current dentry and execute the lookup to return a new
2453 * one with ->d_name pointing to the
2454 * <mount point>/subvol_name.
2455 */
2456 dput(dentry);
2457 if (IS_ERR(parent)) {
2458 err = PTR_ERR(parent);
2459 goto out_drop_write;
2460 }
2461 old_dir = dir;
2462 dir = d_inode(parent);
2463
2464 /*
2465 * If v2 was used with SPEC_BY_ID, a new parent was
2466 * allocated since the subvolume can be outside of the
2467 * current mount point. Later on we need to release this
2468 * new parent dentry.
2469 */
2470 destroy_parent = true;
2471
2472 /*
2473 * On idmapped mounts, deletion via subvolid is
2474 * restricted to subvolumes that are immediate
2475 * ancestors of the inode referenced by the file
2476 * descriptor in the ioctl. Otherwise the idmapping
2477 * could potentially be abused to delete subvolumes
2478 * anywhere in the filesystem the user wouldn't be able
2479 * to delete without an idmapped mount.
2480 */
2481 if (old_dir != dir && idmap != &nop_mnt_idmap) {
2482 err = -EOPNOTSUPP;
2483 goto free_parent;
2484 }
2485
2486 subvol_name_ptr = btrfs_get_subvol_name_from_objectid(
2487 fs_info, vol_args2->subvolid);
2488 if (IS_ERR(subvol_name_ptr)) {
2489 err = PTR_ERR(subvol_name_ptr);
2490 goto free_parent;
2491 }
2492 /* subvol_name_ptr is already nul terminated */
2493 subvol_name = (char *)kbasename(subvol_name_ptr);
2494 }
2495 } else {
2496 vol_args = memdup_user(arg, sizeof(*vol_args));
2497 if (IS_ERR(vol_args))
2498 return PTR_ERR(vol_args);
2499
2500 err = btrfs_check_ioctl_vol_args_path(vol_args);
2501 if (err < 0)
2502 goto out;
2503
2504 subvol_name = vol_args->name;
2505
2506 err = mnt_want_write_file(file);
2507 if (err)
2508 goto out;
2509 }
2510
2511 subvol_namelen = strlen(subvol_name);
2512
2513 if (strchr(subvol_name, '/') ||
2514 strncmp(subvol_name, "..", subvol_namelen) == 0) {
2515 err = -EINVAL;
2516 goto free_subvol_name;
2517 }
2518
2519 if (!S_ISDIR(dir->i_mode)) {
2520 err = -ENOTDIR;
2521 goto free_subvol_name;
2522 }
2523
2524 err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
2525 if (err == -EINTR)
2526 goto free_subvol_name;
2527 dentry = lookup_one(idmap, subvol_name, parent, subvol_namelen);
2528 if (IS_ERR(dentry)) {
2529 err = PTR_ERR(dentry);
2530 goto out_unlock_dir;
2531 }
2532
2533 if (d_really_is_negative(dentry)) {
2534 err = -ENOENT;
2535 goto out_dput;
2536 }
2537
2538 inode = d_inode(dentry);
2539 dest = BTRFS_I(inode)->root;
2540 if (!capable(CAP_SYS_ADMIN)) {
2541 /*
2542 * Regular user. Only allow this with a special mount
2543 * option, when the user has write+exec access to the
2544 * subvol root, and when rmdir(2) would have been
2545 * allowed.
2546 *
2547 * Note that this is _not_ check that the subvol is
2548 * empty or doesn't contain data that we wouldn't
2549 * otherwise be able to delete.
2550 *
2551 * Users who want to delete empty subvols should try
2552 * rmdir(2).
2553 */
2554 err = -EPERM;
2555 if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))
2556 goto out_dput;
2557
2558 /*
2559 * Do not allow deletion if the parent dir is the same
2560 * as the dir to be deleted. That means the ioctl
2561 * must be called on the dentry referencing the root
2562 * of the subvol, not a random directory contained
2563 * within it.
2564 */
2565 err = -EINVAL;
2566 if (root == dest)
2567 goto out_dput;
2568
2569 err = inode_permission(idmap, inode, MAY_WRITE | MAY_EXEC);
2570 if (err)
2571 goto out_dput;
2572 }
2573
2574 /* check if subvolume may be deleted by a user */
2575 err = btrfs_may_delete(idmap, dir, dentry, 1);
2576 if (err)
2577 goto out_dput;
2578
2579 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
2580 err = -EINVAL;
2581 goto out_dput;
2582 }
2583
2584 btrfs_inode_lock(BTRFS_I(inode), 0);
2585 err = btrfs_delete_subvolume(BTRFS_I(dir), dentry);
2586 btrfs_inode_unlock(BTRFS_I(inode), 0);
2587 if (!err)
2588 d_delete_notify(dir, dentry);
2589
2590out_dput:
2591 dput(dentry);
2592out_unlock_dir:
2593 btrfs_inode_unlock(BTRFS_I(dir), 0);
2594free_subvol_name:
2595 kfree(subvol_name_ptr);
2596free_parent:
2597 if (destroy_parent)
2598 dput(parent);
2599out_drop_write:
2600 mnt_drop_write_file(file);
2601out:
2602 kfree(vol_args2);
2603 kfree(vol_args);
2604 return err;
2605}
2606
2607static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2608{
2609 struct inode *inode = file_inode(file);
2610 struct btrfs_root *root = BTRFS_I(inode)->root;
2611 struct btrfs_ioctl_defrag_range_args range = {0};
2612 int ret;
2613
2614 ret = mnt_want_write_file(file);
2615 if (ret)
2616 return ret;
2617
2618 if (btrfs_root_readonly(root)) {
2619 ret = -EROFS;
2620 goto out;
2621 }
2622
2623 switch (inode->i_mode & S_IFMT) {
2624 case S_IFDIR:
2625 if (!capable(CAP_SYS_ADMIN)) {
2626 ret = -EPERM;
2627 goto out;
2628 }
2629 ret = btrfs_defrag_root(root);
2630 break;
2631 case S_IFREG:
2632 /*
2633 * Note that this does not check the file descriptor for write
2634 * access. This prevents defragmenting executables that are
2635 * running and allows defrag on files open in read-only mode.
2636 */
2637 if (!capable(CAP_SYS_ADMIN) &&
2638 inode_permission(&nop_mnt_idmap, inode, MAY_WRITE)) {
2639 ret = -EPERM;
2640 goto out;
2641 }
2642
2643 if (argp) {
2644 if (copy_from_user(&range, argp, sizeof(range))) {
2645 ret = -EFAULT;
2646 goto out;
2647 }
2648 if (range.flags & ~BTRFS_DEFRAG_RANGE_FLAGS_SUPP) {
2649 ret = -EOPNOTSUPP;
2650 goto out;
2651 }
2652 /* compression requires us to start the IO */
2653 if ((range.flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2654 range.flags |= BTRFS_DEFRAG_RANGE_START_IO;
2655 range.extent_thresh = (u32)-1;
2656 }
2657 } else {
2658 /* the rest are all set to zero by kzalloc */
2659 range.len = (u64)-1;
2660 }
2661 ret = btrfs_defrag_file(file_inode(file), &file->f_ra,
2662 &range, BTRFS_OLDEST_GENERATION, 0);
2663 if (ret > 0)
2664 ret = 0;
2665 break;
2666 default:
2667 ret = -EINVAL;
2668 }
2669out:
2670 mnt_drop_write_file(file);
2671 return ret;
2672}
2673
2674static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg)
2675{
2676 struct btrfs_ioctl_vol_args *vol_args;
2677 bool restore_op = false;
2678 int ret;
2679
2680 if (!capable(CAP_SYS_ADMIN))
2681 return -EPERM;
2682
2683 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
2684 btrfs_err(fs_info, "device add not supported on extent tree v2 yet");
2685 return -EINVAL;
2686 }
2687
2688 if (fs_info->fs_devices->temp_fsid) {
2689 btrfs_err(fs_info,
2690 "device add not supported on cloned temp-fsid mount");
2691 return -EINVAL;
2692 }
2693
2694 if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_ADD)) {
2695 if (!btrfs_exclop_start_try_lock(fs_info, BTRFS_EXCLOP_DEV_ADD))
2696 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2697
2698 /*
2699 * We can do the device add because we have a paused balanced,
2700 * change the exclusive op type and remember we should bring
2701 * back the paused balance
2702 */
2703 fs_info->exclusive_operation = BTRFS_EXCLOP_DEV_ADD;
2704 btrfs_exclop_start_unlock(fs_info);
2705 restore_op = true;
2706 }
2707
2708 vol_args = memdup_user(arg, sizeof(*vol_args));
2709 if (IS_ERR(vol_args)) {
2710 ret = PTR_ERR(vol_args);
2711 goto out;
2712 }
2713
2714 ret = btrfs_check_ioctl_vol_args_path(vol_args);
2715 if (ret < 0)
2716 goto out_free;
2717
2718 ret = btrfs_init_new_device(fs_info, vol_args->name);
2719
2720 if (!ret)
2721 btrfs_info(fs_info, "disk added %s", vol_args->name);
2722
2723out_free:
2724 kfree(vol_args);
2725out:
2726 if (restore_op)
2727 btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
2728 else
2729 btrfs_exclop_finish(fs_info);
2730 return ret;
2731}
2732
2733static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
2734{
2735 BTRFS_DEV_LOOKUP_ARGS(args);
2736 struct inode *inode = file_inode(file);
2737 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
2738 struct btrfs_ioctl_vol_args_v2 *vol_args;
2739 struct file *bdev_file = NULL;
2740 int ret;
2741 bool cancel = false;
2742
2743 if (!capable(CAP_SYS_ADMIN))
2744 return -EPERM;
2745
2746 vol_args = memdup_user(arg, sizeof(*vol_args));
2747 if (IS_ERR(vol_args))
2748 return PTR_ERR(vol_args);
2749
2750 if (vol_args->flags & ~BTRFS_DEVICE_REMOVE_ARGS_MASK) {
2751 ret = -EOPNOTSUPP;
2752 goto out;
2753 }
2754
2755 ret = btrfs_check_ioctl_vol_args2_subvol_name(vol_args);
2756 if (ret < 0)
2757 goto out;
2758
2759 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
2760 args.devid = vol_args->devid;
2761 } else if (!strcmp("cancel", vol_args->name)) {
2762 cancel = true;
2763 } else {
2764 ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name);
2765 if (ret)
2766 goto out;
2767 }
2768
2769 ret = mnt_want_write_file(file);
2770 if (ret)
2771 goto out;
2772
2773 ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,
2774 cancel);
2775 if (ret)
2776 goto err_drop;
2777
2778 /* Exclusive operation is now claimed */
2779 ret = btrfs_rm_device(fs_info, &args, &bdev_file);
2780
2781 btrfs_exclop_finish(fs_info);
2782
2783 if (!ret) {
2784 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
2785 btrfs_info(fs_info, "device deleted: id %llu",
2786 vol_args->devid);
2787 else
2788 btrfs_info(fs_info, "device deleted: %s",
2789 vol_args->name);
2790 }
2791err_drop:
2792 mnt_drop_write_file(file);
2793 if (bdev_file)
2794 fput(bdev_file);
2795out:
2796 btrfs_put_dev_args_from_path(&args);
2797 kfree(vol_args);
2798 return ret;
2799}
2800
2801static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2802{
2803 BTRFS_DEV_LOOKUP_ARGS(args);
2804 struct inode *inode = file_inode(file);
2805 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
2806 struct btrfs_ioctl_vol_args *vol_args;
2807 struct file *bdev_file = NULL;
2808 int ret;
2809 bool cancel = false;
2810
2811 if (!capable(CAP_SYS_ADMIN))
2812 return -EPERM;
2813
2814 vol_args = memdup_user(arg, sizeof(*vol_args));
2815 if (IS_ERR(vol_args))
2816 return PTR_ERR(vol_args);
2817
2818 ret = btrfs_check_ioctl_vol_args_path(vol_args);
2819 if (ret < 0)
2820 goto out_free;
2821
2822 if (!strcmp("cancel", vol_args->name)) {
2823 cancel = true;
2824 } else {
2825 ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name);
2826 if (ret)
2827 goto out;
2828 }
2829
2830 ret = mnt_want_write_file(file);
2831 if (ret)
2832 goto out;
2833
2834 ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,
2835 cancel);
2836 if (ret == 0) {
2837 ret = btrfs_rm_device(fs_info, &args, &bdev_file);
2838 if (!ret)
2839 btrfs_info(fs_info, "disk deleted %s", vol_args->name);
2840 btrfs_exclop_finish(fs_info);
2841 }
2842
2843 mnt_drop_write_file(file);
2844 if (bdev_file)
2845 fput(bdev_file);
2846out:
2847 btrfs_put_dev_args_from_path(&args);
2848out_free:
2849 kfree(vol_args);
2850 return ret;
2851}
2852
2853static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,
2854 void __user *arg)
2855{
2856 struct btrfs_ioctl_fs_info_args *fi_args;
2857 struct btrfs_device *device;
2858 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2859 u64 flags_in;
2860 int ret = 0;
2861
2862 fi_args = memdup_user(arg, sizeof(*fi_args));
2863 if (IS_ERR(fi_args))
2864 return PTR_ERR(fi_args);
2865
2866 flags_in = fi_args->flags;
2867 memset(fi_args, 0, sizeof(*fi_args));
2868
2869 rcu_read_lock();
2870 fi_args->num_devices = fs_devices->num_devices;
2871
2872 list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
2873 if (device->devid > fi_args->max_id)
2874 fi_args->max_id = device->devid;
2875 }
2876 rcu_read_unlock();
2877
2878 memcpy(&fi_args->fsid, fs_devices->fsid, sizeof(fi_args->fsid));
2879 fi_args->nodesize = fs_info->nodesize;
2880 fi_args->sectorsize = fs_info->sectorsize;
2881 fi_args->clone_alignment = fs_info->sectorsize;
2882
2883 if (flags_in & BTRFS_FS_INFO_FLAG_CSUM_INFO) {
2884 fi_args->csum_type = btrfs_super_csum_type(fs_info->super_copy);
2885 fi_args->csum_size = btrfs_super_csum_size(fs_info->super_copy);
2886 fi_args->flags |= BTRFS_FS_INFO_FLAG_CSUM_INFO;
2887 }
2888
2889 if (flags_in & BTRFS_FS_INFO_FLAG_GENERATION) {
2890 fi_args->generation = btrfs_get_fs_generation(fs_info);
2891 fi_args->flags |= BTRFS_FS_INFO_FLAG_GENERATION;
2892 }
2893
2894 if (flags_in & BTRFS_FS_INFO_FLAG_METADATA_UUID) {
2895 memcpy(&fi_args->metadata_uuid, fs_devices->metadata_uuid,
2896 sizeof(fi_args->metadata_uuid));
2897 fi_args->flags |= BTRFS_FS_INFO_FLAG_METADATA_UUID;
2898 }
2899
2900 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2901 ret = -EFAULT;
2902
2903 kfree(fi_args);
2904 return ret;
2905}
2906
2907static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,
2908 void __user *arg)
2909{
2910 BTRFS_DEV_LOOKUP_ARGS(args);
2911 struct btrfs_ioctl_dev_info_args *di_args;
2912 struct btrfs_device *dev;
2913 int ret = 0;
2914
2915 di_args = memdup_user(arg, sizeof(*di_args));
2916 if (IS_ERR(di_args))
2917 return PTR_ERR(di_args);
2918
2919 args.devid = di_args->devid;
2920 if (!btrfs_is_empty_uuid(di_args->uuid))
2921 args.uuid = di_args->uuid;
2922
2923 rcu_read_lock();
2924 dev = btrfs_find_device(fs_info->fs_devices, &args);
2925 if (!dev) {
2926 ret = -ENODEV;
2927 goto out;
2928 }
2929
2930 di_args->devid = dev->devid;
2931 di_args->bytes_used = btrfs_device_get_bytes_used(dev);
2932 di_args->total_bytes = btrfs_device_get_total_bytes(dev);
2933 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2934 memcpy(di_args->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
2935 if (dev->name)
2936 strscpy(di_args->path, btrfs_dev_name(dev), sizeof(di_args->path));
2937 else
2938 di_args->path[0] = '\0';
2939
2940out:
2941 rcu_read_unlock();
2942 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2943 ret = -EFAULT;
2944
2945 kfree(di_args);
2946 return ret;
2947}
2948
2949static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2950{
2951 struct inode *inode = file_inode(file);
2952 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
2953 struct btrfs_root *root = BTRFS_I(inode)->root;
2954 struct btrfs_root *new_root;
2955 struct btrfs_dir_item *di;
2956 struct btrfs_trans_handle *trans;
2957 struct btrfs_path *path = NULL;
2958 struct btrfs_disk_key disk_key;
2959 struct fscrypt_str name = FSTR_INIT("default", 7);
2960 u64 objectid = 0;
2961 u64 dir_id;
2962 int ret;
2963
2964 if (!capable(CAP_SYS_ADMIN))
2965 return -EPERM;
2966
2967 ret = mnt_want_write_file(file);
2968 if (ret)
2969 return ret;
2970
2971 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
2972 ret = -EFAULT;
2973 goto out;
2974 }
2975
2976 if (!objectid)
2977 objectid = BTRFS_FS_TREE_OBJECTID;
2978
2979 new_root = btrfs_get_fs_root(fs_info, objectid, true);
2980 if (IS_ERR(new_root)) {
2981 ret = PTR_ERR(new_root);
2982 goto out;
2983 }
2984 if (!is_fstree(new_root->root_key.objectid)) {
2985 ret = -ENOENT;
2986 goto out_free;
2987 }
2988
2989 path = btrfs_alloc_path();
2990 if (!path) {
2991 ret = -ENOMEM;
2992 goto out_free;
2993 }
2994
2995 trans = btrfs_start_transaction(root, 1);
2996 if (IS_ERR(trans)) {
2997 ret = PTR_ERR(trans);
2998 goto out_free;
2999 }
3000
3001 dir_id = btrfs_super_root_dir(fs_info->super_copy);
3002 di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
3003 dir_id, &name, 1);
3004 if (IS_ERR_OR_NULL(di)) {
3005 btrfs_release_path(path);
3006 btrfs_end_transaction(trans);
3007 btrfs_err(fs_info,
3008 "Umm, you don't have the default diritem, this isn't going to work");
3009 ret = -ENOENT;
3010 goto out_free;
3011 }
3012
3013 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3014 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3015 btrfs_mark_buffer_dirty(trans, path->nodes[0]);
3016 btrfs_release_path(path);
3017
3018 btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
3019 btrfs_end_transaction(trans);
3020out_free:
3021 btrfs_put_root(new_root);
3022 btrfs_free_path(path);
3023out:
3024 mnt_drop_write_file(file);
3025 return ret;
3026}
3027
3028static void get_block_group_info(struct list_head *groups_list,
3029 struct btrfs_ioctl_space_info *space)
3030{
3031 struct btrfs_block_group *block_group;
3032
3033 space->total_bytes = 0;
3034 space->used_bytes = 0;
3035 space->flags = 0;
3036 list_for_each_entry(block_group, groups_list, list) {
3037 space->flags = block_group->flags;
3038 space->total_bytes += block_group->length;
3039 space->used_bytes += block_group->used;
3040 }
3041}
3042
3043static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
3044 void __user *arg)
3045{
3046 struct btrfs_ioctl_space_args space_args = { 0 };
3047 struct btrfs_ioctl_space_info space;
3048 struct btrfs_ioctl_space_info *dest;
3049 struct btrfs_ioctl_space_info *dest_orig;
3050 struct btrfs_ioctl_space_info __user *user_dest;
3051 struct btrfs_space_info *info;
3052 static const u64 types[] = {
3053 BTRFS_BLOCK_GROUP_DATA,
3054 BTRFS_BLOCK_GROUP_SYSTEM,
3055 BTRFS_BLOCK_GROUP_METADATA,
3056 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA
3057 };
3058 int num_types = 4;
3059 int alloc_size;
3060 int ret = 0;
3061 u64 slot_count = 0;
3062 int i, c;
3063
3064 if (copy_from_user(&space_args,
3065 (struct btrfs_ioctl_space_args __user *)arg,
3066 sizeof(space_args)))
3067 return -EFAULT;
3068
3069 for (i = 0; i < num_types; i++) {
3070 struct btrfs_space_info *tmp;
3071
3072 info = NULL;
3073 list_for_each_entry(tmp, &fs_info->space_info, list) {
3074 if (tmp->flags == types[i]) {
3075 info = tmp;
3076 break;
3077 }
3078 }
3079
3080 if (!info)
3081 continue;
3082
3083 down_read(&info->groups_sem);
3084 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3085 if (!list_empty(&info->block_groups[c]))
3086 slot_count++;
3087 }
3088 up_read(&info->groups_sem);
3089 }
3090
3091 /*
3092 * Global block reserve, exported as a space_info
3093 */
3094 slot_count++;
3095
3096 /* space_slots == 0 means they are asking for a count */
3097 if (space_args.space_slots == 0) {
3098 space_args.total_spaces = slot_count;
3099 goto out;
3100 }
3101
3102 slot_count = min_t(u64, space_args.space_slots, slot_count);
3103
3104 alloc_size = sizeof(*dest) * slot_count;
3105
3106 /* we generally have at most 6 or so space infos, one for each raid
3107 * level. So, a whole page should be more than enough for everyone
3108 */
3109 if (alloc_size > PAGE_SIZE)
3110 return -ENOMEM;
3111
3112 space_args.total_spaces = 0;
3113 dest = kmalloc(alloc_size, GFP_KERNEL);
3114 if (!dest)
3115 return -ENOMEM;
3116 dest_orig = dest;
3117
3118 /* now we have a buffer to copy into */
3119 for (i = 0; i < num_types; i++) {
3120 struct btrfs_space_info *tmp;
3121
3122 if (!slot_count)
3123 break;
3124
3125 info = NULL;
3126 list_for_each_entry(tmp, &fs_info->space_info, list) {
3127 if (tmp->flags == types[i]) {
3128 info = tmp;
3129 break;
3130 }
3131 }
3132
3133 if (!info)
3134 continue;
3135 down_read(&info->groups_sem);
3136 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3137 if (!list_empty(&info->block_groups[c])) {
3138 get_block_group_info(&info->block_groups[c],
3139 &space);
3140 memcpy(dest, &space, sizeof(space));
3141 dest++;
3142 space_args.total_spaces++;
3143 slot_count--;
3144 }
3145 if (!slot_count)
3146 break;
3147 }
3148 up_read(&info->groups_sem);
3149 }
3150
3151 /*
3152 * Add global block reserve
3153 */
3154 if (slot_count) {
3155 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3156
3157 spin_lock(&block_rsv->lock);
3158 space.total_bytes = block_rsv->size;
3159 space.used_bytes = block_rsv->size - block_rsv->reserved;
3160 spin_unlock(&block_rsv->lock);
3161 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
3162 memcpy(dest, &space, sizeof(space));
3163 space_args.total_spaces++;
3164 }
3165
3166 user_dest = (struct btrfs_ioctl_space_info __user *)
3167 (arg + sizeof(struct btrfs_ioctl_space_args));
3168
3169 if (copy_to_user(user_dest, dest_orig, alloc_size))
3170 ret = -EFAULT;
3171
3172 kfree(dest_orig);
3173out:
3174 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
3175 ret = -EFAULT;
3176
3177 return ret;
3178}
3179
3180static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
3181 void __user *argp)
3182{
3183 struct btrfs_trans_handle *trans;
3184 u64 transid;
3185
3186 /*
3187 * Start orphan cleanup here for the given root in case it hasn't been
3188 * started already by other means. Errors are handled in the other
3189 * functions during transaction commit.
3190 */
3191 btrfs_orphan_cleanup(root);
3192
3193 trans = btrfs_attach_transaction_barrier(root);
3194 if (IS_ERR(trans)) {
3195 if (PTR_ERR(trans) != -ENOENT)
3196 return PTR_ERR(trans);
3197
3198 /* No running transaction, don't bother */
3199 transid = btrfs_get_last_trans_committed(root->fs_info);
3200 goto out;
3201 }
3202 transid = trans->transid;
3203 btrfs_commit_transaction_async(trans);
3204out:
3205 if (argp)
3206 if (copy_to_user(argp, &transid, sizeof(transid)))
3207 return -EFAULT;
3208 return 0;
3209}
3210
3211static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,
3212 void __user *argp)
3213{
3214 /* By default wait for the current transaction. */
3215 u64 transid = 0;
3216
3217 if (argp)
3218 if (copy_from_user(&transid, argp, sizeof(transid)))
3219 return -EFAULT;
3220
3221 return btrfs_wait_for_commit(fs_info, transid);
3222}
3223
3224static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
3225{
3226 struct btrfs_fs_info *fs_info = inode_to_fs_info(file_inode(file));
3227 struct btrfs_ioctl_scrub_args *sa;
3228 int ret;
3229
3230 if (!capable(CAP_SYS_ADMIN))
3231 return -EPERM;
3232
3233 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
3234 btrfs_err(fs_info, "scrub is not supported on extent tree v2 yet");
3235 return -EINVAL;
3236 }
3237
3238 sa = memdup_user(arg, sizeof(*sa));
3239 if (IS_ERR(sa))
3240 return PTR_ERR(sa);
3241
3242 if (sa->flags & ~BTRFS_SCRUB_SUPPORTED_FLAGS) {
3243 ret = -EOPNOTSUPP;
3244 goto out;
3245 }
3246
3247 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
3248 ret = mnt_want_write_file(file);
3249 if (ret)
3250 goto out;
3251 }
3252
3253 ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,
3254 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
3255 0);
3256
3257 /*
3258 * Copy scrub args to user space even if btrfs_scrub_dev() returned an
3259 * error. This is important as it allows user space to know how much
3260 * progress scrub has done. For example, if scrub is canceled we get
3261 * -ECANCELED from btrfs_scrub_dev() and return that error back to user
3262 * space. Later user space can inspect the progress from the structure
3263 * btrfs_ioctl_scrub_args and resume scrub from where it left off
3264 * previously (btrfs-progs does this).
3265 * If we fail to copy the btrfs_ioctl_scrub_args structure to user space
3266 * then return -EFAULT to signal the structure was not copied or it may
3267 * be corrupt and unreliable due to a partial copy.
3268 */
3269 if (copy_to_user(arg, sa, sizeof(*sa)))
3270 ret = -EFAULT;
3271
3272 if (!(sa->flags & BTRFS_SCRUB_READONLY))
3273 mnt_drop_write_file(file);
3274out:
3275 kfree(sa);
3276 return ret;
3277}
3278
3279static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)
3280{
3281 if (!capable(CAP_SYS_ADMIN))
3282 return -EPERM;
3283
3284 return btrfs_scrub_cancel(fs_info);
3285}
3286
3287static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
3288 void __user *arg)
3289{
3290 struct btrfs_ioctl_scrub_args *sa;
3291 int ret;
3292
3293 if (!capable(CAP_SYS_ADMIN))
3294 return -EPERM;
3295
3296 sa = memdup_user(arg, sizeof(*sa));
3297 if (IS_ERR(sa))
3298 return PTR_ERR(sa);
3299
3300 ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
3301
3302 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
3303 ret = -EFAULT;
3304
3305 kfree(sa);
3306 return ret;
3307}
3308
3309static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
3310 void __user *arg)
3311{
3312 struct btrfs_ioctl_get_dev_stats *sa;
3313 int ret;
3314
3315 sa = memdup_user(arg, sizeof(*sa));
3316 if (IS_ERR(sa))
3317 return PTR_ERR(sa);
3318
3319 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3320 kfree(sa);
3321 return -EPERM;
3322 }
3323
3324 ret = btrfs_get_dev_stats(fs_info, sa);
3325
3326 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
3327 ret = -EFAULT;
3328
3329 kfree(sa);
3330 return ret;
3331}
3332
3333static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
3334 void __user *arg)
3335{
3336 struct btrfs_ioctl_dev_replace_args *p;
3337 int ret;
3338
3339 if (!capable(CAP_SYS_ADMIN))
3340 return -EPERM;
3341
3342 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
3343 btrfs_err(fs_info, "device replace not supported on extent tree v2 yet");
3344 return -EINVAL;
3345 }
3346
3347 p = memdup_user(arg, sizeof(*p));
3348 if (IS_ERR(p))
3349 return PTR_ERR(p);
3350
3351 switch (p->cmd) {
3352 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3353 if (sb_rdonly(fs_info->sb)) {
3354 ret = -EROFS;
3355 goto out;
3356 }
3357 if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_REPLACE)) {
3358 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3359 } else {
3360 ret = btrfs_dev_replace_by_ioctl(fs_info, p);
3361 btrfs_exclop_finish(fs_info);
3362 }
3363 break;
3364 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
3365 btrfs_dev_replace_status(fs_info, p);
3366 ret = 0;
3367 break;
3368 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
3369 p->result = btrfs_dev_replace_cancel(fs_info);
3370 ret = 0;
3371 break;
3372 default:
3373 ret = -EINVAL;
3374 break;
3375 }
3376
3377 if ((ret == 0 || ret == -ECANCELED) && copy_to_user(arg, p, sizeof(*p)))
3378 ret = -EFAULT;
3379out:
3380 kfree(p);
3381 return ret;
3382}
3383
3384static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3385{
3386 int ret = 0;
3387 int i;
3388 u64 rel_ptr;
3389 int size;
3390 struct btrfs_ioctl_ino_path_args *ipa = NULL;
3391 struct inode_fs_paths *ipath = NULL;
3392 struct btrfs_path *path;
3393
3394 if (!capable(CAP_DAC_READ_SEARCH))
3395 return -EPERM;
3396
3397 path = btrfs_alloc_path();
3398 if (!path) {
3399 ret = -ENOMEM;
3400 goto out;
3401 }
3402
3403 ipa = memdup_user(arg, sizeof(*ipa));
3404 if (IS_ERR(ipa)) {
3405 ret = PTR_ERR(ipa);
3406 ipa = NULL;
3407 goto out;
3408 }
3409
3410 size = min_t(u32, ipa->size, 4096);
3411 ipath = init_ipath(size, root, path);
3412 if (IS_ERR(ipath)) {
3413 ret = PTR_ERR(ipath);
3414 ipath = NULL;
3415 goto out;
3416 }
3417
3418 ret = paths_from_inode(ipa->inum, ipath);
3419 if (ret < 0)
3420 goto out;
3421
3422 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3423 rel_ptr = ipath->fspath->val[i] -
3424 (u64)(unsigned long)ipath->fspath->val;
3425 ipath->fspath->val[i] = rel_ptr;
3426 }
3427
3428 btrfs_free_path(path);
3429 path = NULL;
3430 ret = copy_to_user((void __user *)(unsigned long)ipa->fspath,
3431 ipath->fspath, size);
3432 if (ret) {
3433 ret = -EFAULT;
3434 goto out;
3435 }
3436
3437out:
3438 btrfs_free_path(path);
3439 free_ipath(ipath);
3440 kfree(ipa);
3441
3442 return ret;
3443}
3444
3445static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,
3446 void __user *arg, int version)
3447{
3448 int ret = 0;
3449 int size;
3450 struct btrfs_ioctl_logical_ino_args *loi;
3451 struct btrfs_data_container *inodes = NULL;
3452 struct btrfs_path *path = NULL;
3453 bool ignore_offset;
3454
3455 if (!capable(CAP_SYS_ADMIN))
3456 return -EPERM;
3457
3458 loi = memdup_user(arg, sizeof(*loi));
3459 if (IS_ERR(loi))
3460 return PTR_ERR(loi);
3461
3462 if (version == 1) {
3463 ignore_offset = false;
3464 size = min_t(u32, loi->size, SZ_64K);
3465 } else {
3466 /* All reserved bits must be 0 for now */
3467 if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) {
3468 ret = -EINVAL;
3469 goto out_loi;
3470 }
3471 /* Only accept flags we have defined so far */
3472 if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) {
3473 ret = -EINVAL;
3474 goto out_loi;
3475 }
3476 ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET;
3477 size = min_t(u32, loi->size, SZ_16M);
3478 }
3479
3480 inodes = init_data_container(size);
3481 if (IS_ERR(inodes)) {
3482 ret = PTR_ERR(inodes);
3483 goto out_loi;
3484 }
3485
3486 path = btrfs_alloc_path();
3487 if (!path) {
3488 ret = -ENOMEM;
3489 goto out;
3490 }
3491 ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
3492 inodes, ignore_offset);
3493 btrfs_free_path(path);
3494 if (ret == -EINVAL)
3495 ret = -ENOENT;
3496 if (ret < 0)
3497 goto out;
3498
3499 ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes,
3500 size);
3501 if (ret)
3502 ret = -EFAULT;
3503
3504out:
3505 kvfree(inodes);
3506out_loi:
3507 kfree(loi);
3508
3509 return ret;
3510}
3511
3512void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info,
3513 struct btrfs_ioctl_balance_args *bargs)
3514{
3515 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3516
3517 bargs->flags = bctl->flags;
3518
3519 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags))
3520 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3521 if (atomic_read(&fs_info->balance_pause_req))
3522 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3523 if (atomic_read(&fs_info->balance_cancel_req))
3524 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3525
3526 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3527 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3528 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3529
3530 spin_lock(&fs_info->balance_lock);
3531 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3532 spin_unlock(&fs_info->balance_lock);
3533}
3534
3535/*
3536 * Try to acquire fs_info::balance_mutex as well as set BTRFS_EXLCOP_BALANCE as
3537 * required.
3538 *
3539 * @fs_info: the filesystem
3540 * @excl_acquired: ptr to boolean value which is set to false in case balance
3541 * is being resumed
3542 *
3543 * Return 0 on success in which case both fs_info::balance is acquired as well
3544 * as exclusive ops are blocked. In case of failure return an error code.
3545 */
3546static int btrfs_try_lock_balance(struct btrfs_fs_info *fs_info, bool *excl_acquired)
3547{
3548 int ret;
3549
3550 /*
3551 * Exclusive operation is locked. Three possibilities:
3552 * (1) some other op is running
3553 * (2) balance is running
3554 * (3) balance is paused -- special case (think resume)
3555 */
3556 while (1) {
3557 if (btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) {
3558 *excl_acquired = true;
3559 mutex_lock(&fs_info->balance_mutex);
3560 return 0;
3561 }
3562
3563 mutex_lock(&fs_info->balance_mutex);
3564 if (fs_info->balance_ctl) {
3565 /* This is either (2) or (3) */
3566 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
3567 /* This is (2) */
3568 ret = -EINPROGRESS;
3569 goto out_failure;
3570
3571 } else {
3572 mutex_unlock(&fs_info->balance_mutex);
3573 /*
3574 * Lock released to allow other waiters to
3575 * continue, we'll reexamine the status again.
3576 */
3577 mutex_lock(&fs_info->balance_mutex);
3578
3579 if (fs_info->balance_ctl &&
3580 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
3581 /* This is (3) */
3582 *excl_acquired = false;
3583 return 0;
3584 }
3585 }
3586 } else {
3587 /* This is (1) */
3588 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3589 goto out_failure;
3590 }
3591
3592 mutex_unlock(&fs_info->balance_mutex);
3593 }
3594
3595out_failure:
3596 mutex_unlock(&fs_info->balance_mutex);
3597 *excl_acquired = false;
3598 return ret;
3599}
3600
3601static long btrfs_ioctl_balance(struct file *file, void __user *arg)
3602{
3603 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3604 struct btrfs_fs_info *fs_info = root->fs_info;
3605 struct btrfs_ioctl_balance_args *bargs;
3606 struct btrfs_balance_control *bctl;
3607 bool need_unlock = true;
3608 int ret;
3609
3610 if (!capable(CAP_SYS_ADMIN))
3611 return -EPERM;
3612
3613 ret = mnt_want_write_file(file);
3614 if (ret)
3615 return ret;
3616
3617 bargs = memdup_user(arg, sizeof(*bargs));
3618 if (IS_ERR(bargs)) {
3619 ret = PTR_ERR(bargs);
3620 bargs = NULL;
3621 goto out;
3622 }
3623
3624 ret = btrfs_try_lock_balance(fs_info, &need_unlock);
3625 if (ret)
3626 goto out;
3627
3628 lockdep_assert_held(&fs_info->balance_mutex);
3629
3630 if (bargs->flags & BTRFS_BALANCE_RESUME) {
3631 if (!fs_info->balance_ctl) {
3632 ret = -ENOTCONN;
3633 goto out_unlock;
3634 }
3635
3636 bctl = fs_info->balance_ctl;
3637 spin_lock(&fs_info->balance_lock);
3638 bctl->flags |= BTRFS_BALANCE_RESUME;
3639 spin_unlock(&fs_info->balance_lock);
3640 btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE);
3641
3642 goto do_balance;
3643 }
3644
3645 if (bargs->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
3646 ret = -EINVAL;
3647 goto out_unlock;
3648 }
3649
3650 if (fs_info->balance_ctl) {
3651 ret = -EINPROGRESS;
3652 goto out_unlock;
3653 }
3654
3655 bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
3656 if (!bctl) {
3657 ret = -ENOMEM;
3658 goto out_unlock;
3659 }
3660
3661 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
3662 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
3663 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
3664
3665 bctl->flags = bargs->flags;
3666do_balance:
3667 /*
3668 * Ownership of bctl and exclusive operation goes to btrfs_balance.
3669 * bctl is freed in reset_balance_state, or, if restriper was paused
3670 * all the way until unmount, in free_fs_info. The flag should be
3671 * cleared after reset_balance_state.
3672 */
3673 need_unlock = false;
3674
3675 ret = btrfs_balance(fs_info, bctl, bargs);
3676 bctl = NULL;
3677
3678 if (ret == 0 || ret == -ECANCELED) {
3679 if (copy_to_user(arg, bargs, sizeof(*bargs)))
3680 ret = -EFAULT;
3681 }
3682
3683 kfree(bctl);
3684out_unlock:
3685 mutex_unlock(&fs_info->balance_mutex);
3686 if (need_unlock)
3687 btrfs_exclop_finish(fs_info);
3688out:
3689 mnt_drop_write_file(file);
3690 kfree(bargs);
3691 return ret;
3692}
3693
3694static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
3695{
3696 if (!capable(CAP_SYS_ADMIN))
3697 return -EPERM;
3698
3699 switch (cmd) {
3700 case BTRFS_BALANCE_CTL_PAUSE:
3701 return btrfs_pause_balance(fs_info);
3702 case BTRFS_BALANCE_CTL_CANCEL:
3703 return btrfs_cancel_balance(fs_info);
3704 }
3705
3706 return -EINVAL;
3707}
3708
3709static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
3710 void __user *arg)
3711{
3712 struct btrfs_ioctl_balance_args *bargs;
3713 int ret = 0;
3714
3715 if (!capable(CAP_SYS_ADMIN))
3716 return -EPERM;
3717
3718 mutex_lock(&fs_info->balance_mutex);
3719 if (!fs_info->balance_ctl) {
3720 ret = -ENOTCONN;
3721 goto out;
3722 }
3723
3724 bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
3725 if (!bargs) {
3726 ret = -ENOMEM;
3727 goto out;
3728 }
3729
3730 btrfs_update_ioctl_balance_args(fs_info, bargs);
3731
3732 if (copy_to_user(arg, bargs, sizeof(*bargs)))
3733 ret = -EFAULT;
3734
3735 kfree(bargs);
3736out:
3737 mutex_unlock(&fs_info->balance_mutex);
3738 return ret;
3739}
3740
3741static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
3742{
3743 struct inode *inode = file_inode(file);
3744 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
3745 struct btrfs_ioctl_quota_ctl_args *sa;
3746 int ret;
3747
3748 if (!capable(CAP_SYS_ADMIN))
3749 return -EPERM;
3750
3751 ret = mnt_want_write_file(file);
3752 if (ret)
3753 return ret;
3754
3755 sa = memdup_user(arg, sizeof(*sa));
3756 if (IS_ERR(sa)) {
3757 ret = PTR_ERR(sa);
3758 goto drop_write;
3759 }
3760
3761 switch (sa->cmd) {
3762 case BTRFS_QUOTA_CTL_ENABLE:
3763 case BTRFS_QUOTA_CTL_ENABLE_SIMPLE_QUOTA:
3764 down_write(&fs_info->subvol_sem);
3765 ret = btrfs_quota_enable(fs_info, sa);
3766 up_write(&fs_info->subvol_sem);
3767 break;
3768 case BTRFS_QUOTA_CTL_DISABLE:
3769 /*
3770 * Lock the cleaner mutex to prevent races with concurrent
3771 * relocation, because relocation may be building backrefs for
3772 * blocks of the quota root while we are deleting the root. This
3773 * is like dropping fs roots of deleted snapshots/subvolumes, we
3774 * need the same protection.
3775 *
3776 * This also prevents races between concurrent tasks trying to
3777 * disable quotas, because we will unlock and relock
3778 * qgroup_ioctl_lock across BTRFS_FS_QUOTA_ENABLED changes.
3779 *
3780 * We take this here because we have the dependency of
3781 *
3782 * inode_lock -> subvol_sem
3783 *
3784 * because of rename. With relocation we can prealloc extents,
3785 * so that makes the dependency chain
3786 *
3787 * cleaner_mutex -> inode_lock -> subvol_sem
3788 *
3789 * so we must take the cleaner_mutex here before we take the
3790 * subvol_sem. The deadlock can't actually happen, but this
3791 * quiets lockdep.
3792 */
3793 mutex_lock(&fs_info->cleaner_mutex);
3794 down_write(&fs_info->subvol_sem);
3795 ret = btrfs_quota_disable(fs_info);
3796 up_write(&fs_info->subvol_sem);
3797 mutex_unlock(&fs_info->cleaner_mutex);
3798 break;
3799 default:
3800 ret = -EINVAL;
3801 break;
3802 }
3803
3804 kfree(sa);
3805drop_write:
3806 mnt_drop_write_file(file);
3807 return ret;
3808}
3809
3810static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
3811{
3812 struct inode *inode = file_inode(file);
3813 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
3814 struct btrfs_root *root = BTRFS_I(inode)->root;
3815 struct btrfs_ioctl_qgroup_assign_args *sa;
3816 struct btrfs_trans_handle *trans;
3817 int ret;
3818 int err;
3819
3820 if (!capable(CAP_SYS_ADMIN))
3821 return -EPERM;
3822
3823 ret = mnt_want_write_file(file);
3824 if (ret)
3825 return ret;
3826
3827 sa = memdup_user(arg, sizeof(*sa));
3828 if (IS_ERR(sa)) {
3829 ret = PTR_ERR(sa);
3830 goto drop_write;
3831 }
3832
3833 trans = btrfs_join_transaction(root);
3834 if (IS_ERR(trans)) {
3835 ret = PTR_ERR(trans);
3836 goto out;
3837 }
3838
3839 if (sa->assign) {
3840 ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst);
3841 } else {
3842 ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst);
3843 }
3844
3845 /* update qgroup status and info */
3846 mutex_lock(&fs_info->qgroup_ioctl_lock);
3847 err = btrfs_run_qgroups(trans);
3848 mutex_unlock(&fs_info->qgroup_ioctl_lock);
3849 if (err < 0)
3850 btrfs_handle_fs_error(fs_info, err,
3851 "failed to update qgroup status and info");
3852 err = btrfs_end_transaction(trans);
3853 if (err && !ret)
3854 ret = err;
3855
3856out:
3857 kfree(sa);
3858drop_write:
3859 mnt_drop_write_file(file);
3860 return ret;
3861}
3862
3863static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
3864{
3865 struct inode *inode = file_inode(file);
3866 struct btrfs_root *root = BTRFS_I(inode)->root;
3867 struct btrfs_ioctl_qgroup_create_args *sa;
3868 struct btrfs_trans_handle *trans;
3869 int ret;
3870 int err;
3871
3872 if (!capable(CAP_SYS_ADMIN))
3873 return -EPERM;
3874
3875 ret = mnt_want_write_file(file);
3876 if (ret)
3877 return ret;
3878
3879 sa = memdup_user(arg, sizeof(*sa));
3880 if (IS_ERR(sa)) {
3881 ret = PTR_ERR(sa);
3882 goto drop_write;
3883 }
3884
3885 if (!sa->qgroupid) {
3886 ret = -EINVAL;
3887 goto out;
3888 }
3889
3890 if (sa->create && is_fstree(sa->qgroupid)) {
3891 ret = -EINVAL;
3892 goto out;
3893 }
3894
3895 trans = btrfs_join_transaction(root);
3896 if (IS_ERR(trans)) {
3897 ret = PTR_ERR(trans);
3898 goto out;
3899 }
3900
3901 if (sa->create) {
3902 ret = btrfs_create_qgroup(trans, sa->qgroupid);
3903 } else {
3904 ret = btrfs_remove_qgroup(trans, sa->qgroupid);
3905 }
3906
3907 err = btrfs_end_transaction(trans);
3908 if (err && !ret)
3909 ret = err;
3910
3911out:
3912 kfree(sa);
3913drop_write:
3914 mnt_drop_write_file(file);
3915 return ret;
3916}
3917
3918static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
3919{
3920 struct inode *inode = file_inode(file);
3921 struct btrfs_root *root = BTRFS_I(inode)->root;
3922 struct btrfs_ioctl_qgroup_limit_args *sa;
3923 struct btrfs_trans_handle *trans;
3924 int ret;
3925 int err;
3926 u64 qgroupid;
3927
3928 if (!capable(CAP_SYS_ADMIN))
3929 return -EPERM;
3930
3931 ret = mnt_want_write_file(file);
3932 if (ret)
3933 return ret;
3934
3935 sa = memdup_user(arg, sizeof(*sa));
3936 if (IS_ERR(sa)) {
3937 ret = PTR_ERR(sa);
3938 goto drop_write;
3939 }
3940
3941 trans = btrfs_join_transaction(root);
3942 if (IS_ERR(trans)) {
3943 ret = PTR_ERR(trans);
3944 goto out;
3945 }
3946
3947 qgroupid = sa->qgroupid;
3948 if (!qgroupid) {
3949 /* take the current subvol as qgroup */
3950 qgroupid = root->root_key.objectid;
3951 }
3952
3953 ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim);
3954
3955 err = btrfs_end_transaction(trans);
3956 if (err && !ret)
3957 ret = err;
3958
3959out:
3960 kfree(sa);
3961drop_write:
3962 mnt_drop_write_file(file);
3963 return ret;
3964}
3965
3966static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
3967{
3968 struct inode *inode = file_inode(file);
3969 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
3970 struct btrfs_ioctl_quota_rescan_args *qsa;
3971 int ret;
3972
3973 if (!capable(CAP_SYS_ADMIN))
3974 return -EPERM;
3975
3976 ret = mnt_want_write_file(file);
3977 if (ret)
3978 return ret;
3979
3980 qsa = memdup_user(arg, sizeof(*qsa));
3981 if (IS_ERR(qsa)) {
3982 ret = PTR_ERR(qsa);
3983 goto drop_write;
3984 }
3985
3986 if (qsa->flags) {
3987 ret = -EINVAL;
3988 goto out;
3989 }
3990
3991 ret = btrfs_qgroup_rescan(fs_info);
3992
3993out:
3994 kfree(qsa);
3995drop_write:
3996 mnt_drop_write_file(file);
3997 return ret;
3998}
3999
4000static long btrfs_ioctl_quota_rescan_status(struct btrfs_fs_info *fs_info,
4001 void __user *arg)
4002{
4003 struct btrfs_ioctl_quota_rescan_args qsa = {0};
4004
4005 if (!capable(CAP_SYS_ADMIN))
4006 return -EPERM;
4007
4008 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4009 qsa.flags = 1;
4010 qsa.progress = fs_info->qgroup_rescan_progress.objectid;
4011 }
4012
4013 if (copy_to_user(arg, &qsa, sizeof(qsa)))
4014 return -EFAULT;
4015
4016 return 0;
4017}
4018
4019static long btrfs_ioctl_quota_rescan_wait(struct btrfs_fs_info *fs_info,
4020 void __user *arg)
4021{
4022 if (!capable(CAP_SYS_ADMIN))
4023 return -EPERM;
4024
4025 return btrfs_qgroup_wait_for_completion(fs_info, true);
4026}
4027
4028static long _btrfs_ioctl_set_received_subvol(struct file *file,
4029 struct mnt_idmap *idmap,
4030 struct btrfs_ioctl_received_subvol_args *sa)
4031{
4032 struct inode *inode = file_inode(file);
4033 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
4034 struct btrfs_root *root = BTRFS_I(inode)->root;
4035 struct btrfs_root_item *root_item = &root->root_item;
4036 struct btrfs_trans_handle *trans;
4037 struct timespec64 ct = current_time(inode);
4038 int ret = 0;
4039 int received_uuid_changed;
4040
4041 if (!inode_owner_or_capable(idmap, inode))
4042 return -EPERM;
4043
4044 ret = mnt_want_write_file(file);
4045 if (ret < 0)
4046 return ret;
4047
4048 down_write(&fs_info->subvol_sem);
4049
4050 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
4051 ret = -EINVAL;
4052 goto out;
4053 }
4054
4055 if (btrfs_root_readonly(root)) {
4056 ret = -EROFS;
4057 goto out;
4058 }
4059
4060 /*
4061 * 1 - root item
4062 * 2 - uuid items (received uuid + subvol uuid)
4063 */
4064 trans = btrfs_start_transaction(root, 3);
4065 if (IS_ERR(trans)) {
4066 ret = PTR_ERR(trans);
4067 trans = NULL;
4068 goto out;
4069 }
4070
4071 sa->rtransid = trans->transid;
4072 sa->rtime.sec = ct.tv_sec;
4073 sa->rtime.nsec = ct.tv_nsec;
4074
4075 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4076 BTRFS_UUID_SIZE);
4077 if (received_uuid_changed &&
4078 !btrfs_is_empty_uuid(root_item->received_uuid)) {
4079 ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid,
4080 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4081 root->root_key.objectid);
4082 if (ret && ret != -ENOENT) {
4083 btrfs_abort_transaction(trans, ret);
4084 btrfs_end_transaction(trans);
4085 goto out;
4086 }
4087 }
4088 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4089 btrfs_set_root_stransid(root_item, sa->stransid);
4090 btrfs_set_root_rtransid(root_item, sa->rtransid);
4091 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4092 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4093 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4094 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4095
4096 ret = btrfs_update_root(trans, fs_info->tree_root,
4097 &root->root_key, &root->root_item);
4098 if (ret < 0) {
4099 btrfs_end_transaction(trans);
4100 goto out;
4101 }
4102 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4103 ret = btrfs_uuid_tree_add(trans, sa->uuid,
4104 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4105 root->root_key.objectid);
4106 if (ret < 0 && ret != -EEXIST) {
4107 btrfs_abort_transaction(trans, ret);
4108 btrfs_end_transaction(trans);
4109 goto out;
4110 }
4111 }
4112 ret = btrfs_commit_transaction(trans);
4113out:
4114 up_write(&fs_info->subvol_sem);
4115 mnt_drop_write_file(file);
4116 return ret;
4117}
4118
4119#ifdef CONFIG_64BIT
4120static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4121 void __user *arg)
4122{
4123 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4124 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4125 int ret = 0;
4126
4127 args32 = memdup_user(arg, sizeof(*args32));
4128 if (IS_ERR(args32))
4129 return PTR_ERR(args32);
4130
4131 args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
4132 if (!args64) {
4133 ret = -ENOMEM;
4134 goto out;
4135 }
4136
4137 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4138 args64->stransid = args32->stransid;
4139 args64->rtransid = args32->rtransid;
4140 args64->stime.sec = args32->stime.sec;
4141 args64->stime.nsec = args32->stime.nsec;
4142 args64->rtime.sec = args32->rtime.sec;
4143 args64->rtime.nsec = args32->rtime.nsec;
4144 args64->flags = args32->flags;
4145
4146 ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_idmap(file), args64);
4147 if (ret)
4148 goto out;
4149
4150 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4151 args32->stransid = args64->stransid;
4152 args32->rtransid = args64->rtransid;
4153 args32->stime.sec = args64->stime.sec;
4154 args32->stime.nsec = args64->stime.nsec;
4155 args32->rtime.sec = args64->rtime.sec;
4156 args32->rtime.nsec = args64->rtime.nsec;
4157 args32->flags = args64->flags;
4158
4159 ret = copy_to_user(arg, args32, sizeof(*args32));
4160 if (ret)
4161 ret = -EFAULT;
4162
4163out:
4164 kfree(args32);
4165 kfree(args64);
4166 return ret;
4167}
4168#endif
4169
4170static long btrfs_ioctl_set_received_subvol(struct file *file,
4171 void __user *arg)
4172{
4173 struct btrfs_ioctl_received_subvol_args *sa = NULL;
4174 int ret = 0;
4175
4176 sa = memdup_user(arg, sizeof(*sa));
4177 if (IS_ERR(sa))
4178 return PTR_ERR(sa);
4179
4180 ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_idmap(file), sa);
4181
4182 if (ret)
4183 goto out;
4184
4185 ret = copy_to_user(arg, sa, sizeof(*sa));
4186 if (ret)
4187 ret = -EFAULT;
4188
4189out:
4190 kfree(sa);
4191 return ret;
4192}
4193
4194static int btrfs_ioctl_get_fslabel(struct btrfs_fs_info *fs_info,
4195 void __user *arg)
4196{
4197 size_t len;
4198 int ret;
4199 char label[BTRFS_LABEL_SIZE];
4200
4201 spin_lock(&fs_info->super_lock);
4202 memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
4203 spin_unlock(&fs_info->super_lock);
4204
4205 len = strnlen(label, BTRFS_LABEL_SIZE);
4206
4207 if (len == BTRFS_LABEL_SIZE) {
4208 btrfs_warn(fs_info,
4209 "label is too long, return the first %zu bytes",
4210 --len);
4211 }
4212
4213 ret = copy_to_user(arg, label, len);
4214
4215 return ret ? -EFAULT : 0;
4216}
4217
4218static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
4219{
4220 struct inode *inode = file_inode(file);
4221 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
4222 struct btrfs_root *root = BTRFS_I(inode)->root;
4223 struct btrfs_super_block *super_block = fs_info->super_copy;
4224 struct btrfs_trans_handle *trans;
4225 char label[BTRFS_LABEL_SIZE];
4226 int ret;
4227
4228 if (!capable(CAP_SYS_ADMIN))
4229 return -EPERM;
4230
4231 if (copy_from_user(label, arg, sizeof(label)))
4232 return -EFAULT;
4233
4234 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
4235 btrfs_err(fs_info,
4236 "unable to set label with more than %d bytes",
4237 BTRFS_LABEL_SIZE - 1);
4238 return -EINVAL;
4239 }
4240
4241 ret = mnt_want_write_file(file);
4242 if (ret)
4243 return ret;
4244
4245 trans = btrfs_start_transaction(root, 0);
4246 if (IS_ERR(trans)) {
4247 ret = PTR_ERR(trans);
4248 goto out_unlock;
4249 }
4250
4251 spin_lock(&fs_info->super_lock);
4252 strcpy(super_block->label, label);
4253 spin_unlock(&fs_info->super_lock);
4254 ret = btrfs_commit_transaction(trans);
4255
4256out_unlock:
4257 mnt_drop_write_file(file);
4258 return ret;
4259}
4260
4261#define INIT_FEATURE_FLAGS(suffix) \
4262 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
4263 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
4264 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
4265
4266int btrfs_ioctl_get_supported_features(void __user *arg)
4267{
4268 static const struct btrfs_ioctl_feature_flags features[3] = {
4269 INIT_FEATURE_FLAGS(SUPP),
4270 INIT_FEATURE_FLAGS(SAFE_SET),
4271 INIT_FEATURE_FLAGS(SAFE_CLEAR)
4272 };
4273
4274 if (copy_to_user(arg, &features, sizeof(features)))
4275 return -EFAULT;
4276
4277 return 0;
4278}
4279
4280static int btrfs_ioctl_get_features(struct btrfs_fs_info *fs_info,
4281 void __user *arg)
4282{
4283 struct btrfs_super_block *super_block = fs_info->super_copy;
4284 struct btrfs_ioctl_feature_flags features;
4285
4286 features.compat_flags = btrfs_super_compat_flags(super_block);
4287 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
4288 features.incompat_flags = btrfs_super_incompat_flags(super_block);
4289
4290 if (copy_to_user(arg, &features, sizeof(features)))
4291 return -EFAULT;
4292
4293 return 0;
4294}
4295
4296static int check_feature_bits(struct btrfs_fs_info *fs_info,
4297 enum btrfs_feature_set set,
4298 u64 change_mask, u64 flags, u64 supported_flags,
4299 u64 safe_set, u64 safe_clear)
4300{
4301 const char *type = btrfs_feature_set_name(set);
4302 char *names;
4303 u64 disallowed, unsupported;
4304 u64 set_mask = flags & change_mask;
4305 u64 clear_mask = ~flags & change_mask;
4306
4307 unsupported = set_mask & ~supported_flags;
4308 if (unsupported) {
4309 names = btrfs_printable_features(set, unsupported);
4310 if (names) {
4311 btrfs_warn(fs_info,
4312 "this kernel does not support the %s feature bit%s",
4313 names, strchr(names, ',') ? "s" : "");
4314 kfree(names);
4315 } else
4316 btrfs_warn(fs_info,
4317 "this kernel does not support %s bits 0x%llx",
4318 type, unsupported);
4319 return -EOPNOTSUPP;
4320 }
4321
4322 disallowed = set_mask & ~safe_set;
4323 if (disallowed) {
4324 names = btrfs_printable_features(set, disallowed);
4325 if (names) {
4326 btrfs_warn(fs_info,
4327 "can't set the %s feature bit%s while mounted",
4328 names, strchr(names, ',') ? "s" : "");
4329 kfree(names);
4330 } else
4331 btrfs_warn(fs_info,
4332 "can't set %s bits 0x%llx while mounted",
4333 type, disallowed);
4334 return -EPERM;
4335 }
4336
4337 disallowed = clear_mask & ~safe_clear;
4338 if (disallowed) {
4339 names = btrfs_printable_features(set, disallowed);
4340 if (names) {
4341 btrfs_warn(fs_info,
4342 "can't clear the %s feature bit%s while mounted",
4343 names, strchr(names, ',') ? "s" : "");
4344 kfree(names);
4345 } else
4346 btrfs_warn(fs_info,
4347 "can't clear %s bits 0x%llx while mounted",
4348 type, disallowed);
4349 return -EPERM;
4350 }
4351
4352 return 0;
4353}
4354
4355#define check_feature(fs_info, change_mask, flags, mask_base) \
4356check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags, \
4357 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
4358 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
4359 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
4360
4361static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
4362{
4363 struct inode *inode = file_inode(file);
4364 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
4365 struct btrfs_root *root = BTRFS_I(inode)->root;
4366 struct btrfs_super_block *super_block = fs_info->super_copy;
4367 struct btrfs_ioctl_feature_flags flags[2];
4368 struct btrfs_trans_handle *trans;
4369 u64 newflags;
4370 int ret;
4371
4372 if (!capable(CAP_SYS_ADMIN))
4373 return -EPERM;
4374
4375 if (copy_from_user(flags, arg, sizeof(flags)))
4376 return -EFAULT;
4377
4378 /* Nothing to do */
4379 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
4380 !flags[0].incompat_flags)
4381 return 0;
4382
4383 ret = check_feature(fs_info, flags[0].compat_flags,
4384 flags[1].compat_flags, COMPAT);
4385 if (ret)
4386 return ret;
4387
4388 ret = check_feature(fs_info, flags[0].compat_ro_flags,
4389 flags[1].compat_ro_flags, COMPAT_RO);
4390 if (ret)
4391 return ret;
4392
4393 ret = check_feature(fs_info, flags[0].incompat_flags,
4394 flags[1].incompat_flags, INCOMPAT);
4395 if (ret)
4396 return ret;
4397
4398 ret = mnt_want_write_file(file);
4399 if (ret)
4400 return ret;
4401
4402 trans = btrfs_start_transaction(root, 0);
4403 if (IS_ERR(trans)) {
4404 ret = PTR_ERR(trans);
4405 goto out_drop_write;
4406 }
4407
4408 spin_lock(&fs_info->super_lock);
4409 newflags = btrfs_super_compat_flags(super_block);
4410 newflags |= flags[0].compat_flags & flags[1].compat_flags;
4411 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
4412 btrfs_set_super_compat_flags(super_block, newflags);
4413
4414 newflags = btrfs_super_compat_ro_flags(super_block);
4415 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
4416 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
4417 btrfs_set_super_compat_ro_flags(super_block, newflags);
4418
4419 newflags = btrfs_super_incompat_flags(super_block);
4420 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
4421 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
4422 btrfs_set_super_incompat_flags(super_block, newflags);
4423 spin_unlock(&fs_info->super_lock);
4424
4425 ret = btrfs_commit_transaction(trans);
4426out_drop_write:
4427 mnt_drop_write_file(file);
4428
4429 return ret;
4430}
4431
4432static int _btrfs_ioctl_send(struct inode *inode, void __user *argp, bool compat)
4433{
4434 struct btrfs_ioctl_send_args *arg;
4435 int ret;
4436
4437 if (compat) {
4438#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4439 struct btrfs_ioctl_send_args_32 args32 = { 0 };
4440
4441 ret = copy_from_user(&args32, argp, sizeof(args32));
4442 if (ret)
4443 return -EFAULT;
4444 arg = kzalloc(sizeof(*arg), GFP_KERNEL);
4445 if (!arg)
4446 return -ENOMEM;
4447 arg->send_fd = args32.send_fd;
4448 arg->clone_sources_count = args32.clone_sources_count;
4449 arg->clone_sources = compat_ptr(args32.clone_sources);
4450 arg->parent_root = args32.parent_root;
4451 arg->flags = args32.flags;
4452 arg->version = args32.version;
4453 memcpy(arg->reserved, args32.reserved,
4454 sizeof(args32.reserved));
4455#else
4456 return -ENOTTY;
4457#endif
4458 } else {
4459 arg = memdup_user(argp, sizeof(*arg));
4460 if (IS_ERR(arg))
4461 return PTR_ERR(arg);
4462 }
4463 ret = btrfs_ioctl_send(inode, arg);
4464 kfree(arg);
4465 return ret;
4466}
4467
4468static int btrfs_ioctl_encoded_read(struct file *file, void __user *argp,
4469 bool compat)
4470{
4471 struct btrfs_ioctl_encoded_io_args args = { 0 };
4472 size_t copy_end_kernel = offsetofend(struct btrfs_ioctl_encoded_io_args,
4473 flags);
4474 size_t copy_end;
4475 struct iovec iovstack[UIO_FASTIOV];
4476 struct iovec *iov = iovstack;
4477 struct iov_iter iter;
4478 loff_t pos;
4479 struct kiocb kiocb;
4480 ssize_t ret;
4481
4482 if (!capable(CAP_SYS_ADMIN)) {
4483 ret = -EPERM;
4484 goto out_acct;
4485 }
4486
4487 if (compat) {
4488#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4489 struct btrfs_ioctl_encoded_io_args_32 args32;
4490
4491 copy_end = offsetofend(struct btrfs_ioctl_encoded_io_args_32,
4492 flags);
4493 if (copy_from_user(&args32, argp, copy_end)) {
4494 ret = -EFAULT;
4495 goto out_acct;
4496 }
4497 args.iov = compat_ptr(args32.iov);
4498 args.iovcnt = args32.iovcnt;
4499 args.offset = args32.offset;
4500 args.flags = args32.flags;
4501#else
4502 return -ENOTTY;
4503#endif
4504 } else {
4505 copy_end = copy_end_kernel;
4506 if (copy_from_user(&args, argp, copy_end)) {
4507 ret = -EFAULT;
4508 goto out_acct;
4509 }
4510 }
4511 if (args.flags != 0) {
4512 ret = -EINVAL;
4513 goto out_acct;
4514 }
4515
4516 ret = import_iovec(ITER_DEST, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),
4517 &iov, &iter);
4518 if (ret < 0)
4519 goto out_acct;
4520
4521 if (iov_iter_count(&iter) == 0) {
4522 ret = 0;
4523 goto out_iov;
4524 }
4525 pos = args.offset;
4526 ret = rw_verify_area(READ, file, &pos, args.len);
4527 if (ret < 0)
4528 goto out_iov;
4529
4530 init_sync_kiocb(&kiocb, file);
4531 kiocb.ki_pos = pos;
4532
4533 ret = btrfs_encoded_read(&kiocb, &iter, &args);
4534 if (ret >= 0) {
4535 fsnotify_access(file);
4536 if (copy_to_user(argp + copy_end,
4537 (char *)&args + copy_end_kernel,
4538 sizeof(args) - copy_end_kernel))
4539 ret = -EFAULT;
4540 }
4541
4542out_iov:
4543 kfree(iov);
4544out_acct:
4545 if (ret > 0)
4546 add_rchar(current, ret);
4547 inc_syscr(current);
4548 return ret;
4549}
4550
4551static int btrfs_ioctl_encoded_write(struct file *file, void __user *argp, bool compat)
4552{
4553 struct btrfs_ioctl_encoded_io_args args;
4554 struct iovec iovstack[UIO_FASTIOV];
4555 struct iovec *iov = iovstack;
4556 struct iov_iter iter;
4557 loff_t pos;
4558 struct kiocb kiocb;
4559 ssize_t ret;
4560
4561 if (!capable(CAP_SYS_ADMIN)) {
4562 ret = -EPERM;
4563 goto out_acct;
4564 }
4565
4566 if (!(file->f_mode & FMODE_WRITE)) {
4567 ret = -EBADF;
4568 goto out_acct;
4569 }
4570
4571 if (compat) {
4572#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4573 struct btrfs_ioctl_encoded_io_args_32 args32;
4574
4575 if (copy_from_user(&args32, argp, sizeof(args32))) {
4576 ret = -EFAULT;
4577 goto out_acct;
4578 }
4579 args.iov = compat_ptr(args32.iov);
4580 args.iovcnt = args32.iovcnt;
4581 args.offset = args32.offset;
4582 args.flags = args32.flags;
4583 args.len = args32.len;
4584 args.unencoded_len = args32.unencoded_len;
4585 args.unencoded_offset = args32.unencoded_offset;
4586 args.compression = args32.compression;
4587 args.encryption = args32.encryption;
4588 memcpy(args.reserved, args32.reserved, sizeof(args.reserved));
4589#else
4590 return -ENOTTY;
4591#endif
4592 } else {
4593 if (copy_from_user(&args, argp, sizeof(args))) {
4594 ret = -EFAULT;
4595 goto out_acct;
4596 }
4597 }
4598
4599 ret = -EINVAL;
4600 if (args.flags != 0)
4601 goto out_acct;
4602 if (memchr_inv(args.reserved, 0, sizeof(args.reserved)))
4603 goto out_acct;
4604 if (args.compression == BTRFS_ENCODED_IO_COMPRESSION_NONE &&
4605 args.encryption == BTRFS_ENCODED_IO_ENCRYPTION_NONE)
4606 goto out_acct;
4607 if (args.compression >= BTRFS_ENCODED_IO_COMPRESSION_TYPES ||
4608 args.encryption >= BTRFS_ENCODED_IO_ENCRYPTION_TYPES)
4609 goto out_acct;
4610 if (args.unencoded_offset > args.unencoded_len)
4611 goto out_acct;
4612 if (args.len > args.unencoded_len - args.unencoded_offset)
4613 goto out_acct;
4614
4615 ret = import_iovec(ITER_SOURCE, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),
4616 &iov, &iter);
4617 if (ret < 0)
4618 goto out_acct;
4619
4620 if (iov_iter_count(&iter) == 0) {
4621 ret = 0;
4622 goto out_iov;
4623 }
4624 pos = args.offset;
4625 ret = rw_verify_area(WRITE, file, &pos, args.len);
4626 if (ret < 0)
4627 goto out_iov;
4628
4629 init_sync_kiocb(&kiocb, file);
4630 ret = kiocb_set_rw_flags(&kiocb, 0);
4631 if (ret)
4632 goto out_iov;
4633 kiocb.ki_pos = pos;
4634
4635 file_start_write(file);
4636
4637 ret = btrfs_do_write_iter(&kiocb, &iter, &args);
4638 if (ret > 0)
4639 fsnotify_modify(file);
4640
4641 file_end_write(file);
4642out_iov:
4643 kfree(iov);
4644out_acct:
4645 if (ret > 0)
4646 add_wchar(current, ret);
4647 inc_syscw(current);
4648 return ret;
4649}
4650
4651long btrfs_ioctl(struct file *file, unsigned int
4652 cmd, unsigned long arg)
4653{
4654 struct inode *inode = file_inode(file);
4655 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);
4656 struct btrfs_root *root = BTRFS_I(inode)->root;
4657 void __user *argp = (void __user *)arg;
4658
4659 switch (cmd) {
4660 case FS_IOC_GETVERSION:
4661 return btrfs_ioctl_getversion(inode, argp);
4662 case FS_IOC_GETFSLABEL:
4663 return btrfs_ioctl_get_fslabel(fs_info, argp);
4664 case FS_IOC_SETFSLABEL:
4665 return btrfs_ioctl_set_fslabel(file, argp);
4666 case FITRIM:
4667 return btrfs_ioctl_fitrim(fs_info, argp);
4668 case BTRFS_IOC_SNAP_CREATE:
4669 return btrfs_ioctl_snap_create(file, argp, 0);
4670 case BTRFS_IOC_SNAP_CREATE_V2:
4671 return btrfs_ioctl_snap_create_v2(file, argp, 0);
4672 case BTRFS_IOC_SUBVOL_CREATE:
4673 return btrfs_ioctl_snap_create(file, argp, 1);
4674 case BTRFS_IOC_SUBVOL_CREATE_V2:
4675 return btrfs_ioctl_snap_create_v2(file, argp, 1);
4676 case BTRFS_IOC_SNAP_DESTROY:
4677 return btrfs_ioctl_snap_destroy(file, argp, false);
4678 case BTRFS_IOC_SNAP_DESTROY_V2:
4679 return btrfs_ioctl_snap_destroy(file, argp, true);
4680 case BTRFS_IOC_SUBVOL_GETFLAGS:
4681 return btrfs_ioctl_subvol_getflags(inode, argp);
4682 case BTRFS_IOC_SUBVOL_SETFLAGS:
4683 return btrfs_ioctl_subvol_setflags(file, argp);
4684 case BTRFS_IOC_DEFAULT_SUBVOL:
4685 return btrfs_ioctl_default_subvol(file, argp);
4686 case BTRFS_IOC_DEFRAG:
4687 return btrfs_ioctl_defrag(file, NULL);
4688 case BTRFS_IOC_DEFRAG_RANGE:
4689 return btrfs_ioctl_defrag(file, argp);
4690 case BTRFS_IOC_RESIZE:
4691 return btrfs_ioctl_resize(file, argp);
4692 case BTRFS_IOC_ADD_DEV:
4693 return btrfs_ioctl_add_dev(fs_info, argp);
4694 case BTRFS_IOC_RM_DEV:
4695 return btrfs_ioctl_rm_dev(file, argp);
4696 case BTRFS_IOC_RM_DEV_V2:
4697 return btrfs_ioctl_rm_dev_v2(file, argp);
4698 case BTRFS_IOC_FS_INFO:
4699 return btrfs_ioctl_fs_info(fs_info, argp);
4700 case BTRFS_IOC_DEV_INFO:
4701 return btrfs_ioctl_dev_info(fs_info, argp);
4702 case BTRFS_IOC_TREE_SEARCH:
4703 return btrfs_ioctl_tree_search(inode, argp);
4704 case BTRFS_IOC_TREE_SEARCH_V2:
4705 return btrfs_ioctl_tree_search_v2(inode, argp);
4706 case BTRFS_IOC_INO_LOOKUP:
4707 return btrfs_ioctl_ino_lookup(root, argp);
4708 case BTRFS_IOC_INO_PATHS:
4709 return btrfs_ioctl_ino_to_path(root, argp);
4710 case BTRFS_IOC_LOGICAL_INO:
4711 return btrfs_ioctl_logical_to_ino(fs_info, argp, 1);
4712 case BTRFS_IOC_LOGICAL_INO_V2:
4713 return btrfs_ioctl_logical_to_ino(fs_info, argp, 2);
4714 case BTRFS_IOC_SPACE_INFO:
4715 return btrfs_ioctl_space_info(fs_info, argp);
4716 case BTRFS_IOC_SYNC: {
4717 int ret;
4718
4719 ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false);
4720 if (ret)
4721 return ret;
4722 ret = btrfs_sync_fs(inode->i_sb, 1);
4723 /*
4724 * The transaction thread may want to do more work,
4725 * namely it pokes the cleaner kthread that will start
4726 * processing uncleaned subvols.
4727 */
4728 wake_up_process(fs_info->transaction_kthread);
4729 return ret;
4730 }
4731 case BTRFS_IOC_START_SYNC:
4732 return btrfs_ioctl_start_sync(root, argp);
4733 case BTRFS_IOC_WAIT_SYNC:
4734 return btrfs_ioctl_wait_sync(fs_info, argp);
4735 case BTRFS_IOC_SCRUB:
4736 return btrfs_ioctl_scrub(file, argp);
4737 case BTRFS_IOC_SCRUB_CANCEL:
4738 return btrfs_ioctl_scrub_cancel(fs_info);
4739 case BTRFS_IOC_SCRUB_PROGRESS:
4740 return btrfs_ioctl_scrub_progress(fs_info, argp);
4741 case BTRFS_IOC_BALANCE_V2:
4742 return btrfs_ioctl_balance(file, argp);
4743 case BTRFS_IOC_BALANCE_CTL:
4744 return btrfs_ioctl_balance_ctl(fs_info, arg);
4745 case BTRFS_IOC_BALANCE_PROGRESS:
4746 return btrfs_ioctl_balance_progress(fs_info, argp);
4747 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
4748 return btrfs_ioctl_set_received_subvol(file, argp);
4749#ifdef CONFIG_64BIT
4750 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
4751 return btrfs_ioctl_set_received_subvol_32(file, argp);
4752#endif
4753 case BTRFS_IOC_SEND:
4754 return _btrfs_ioctl_send(inode, argp, false);
4755#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4756 case BTRFS_IOC_SEND_32:
4757 return _btrfs_ioctl_send(inode, argp, true);
4758#endif
4759 case BTRFS_IOC_GET_DEV_STATS:
4760 return btrfs_ioctl_get_dev_stats(fs_info, argp);
4761 case BTRFS_IOC_QUOTA_CTL:
4762 return btrfs_ioctl_quota_ctl(file, argp);
4763 case BTRFS_IOC_QGROUP_ASSIGN:
4764 return btrfs_ioctl_qgroup_assign(file, argp);
4765 case BTRFS_IOC_QGROUP_CREATE:
4766 return btrfs_ioctl_qgroup_create(file, argp);
4767 case BTRFS_IOC_QGROUP_LIMIT:
4768 return btrfs_ioctl_qgroup_limit(file, argp);
4769 case BTRFS_IOC_QUOTA_RESCAN:
4770 return btrfs_ioctl_quota_rescan(file, argp);
4771 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
4772 return btrfs_ioctl_quota_rescan_status(fs_info, argp);
4773 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
4774 return btrfs_ioctl_quota_rescan_wait(fs_info, argp);
4775 case BTRFS_IOC_DEV_REPLACE:
4776 return btrfs_ioctl_dev_replace(fs_info, argp);
4777 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
4778 return btrfs_ioctl_get_supported_features(argp);
4779 case BTRFS_IOC_GET_FEATURES:
4780 return btrfs_ioctl_get_features(fs_info, argp);
4781 case BTRFS_IOC_SET_FEATURES:
4782 return btrfs_ioctl_set_features(file, argp);
4783 case BTRFS_IOC_GET_SUBVOL_INFO:
4784 return btrfs_ioctl_get_subvol_info(inode, argp);
4785 case BTRFS_IOC_GET_SUBVOL_ROOTREF:
4786 return btrfs_ioctl_get_subvol_rootref(root, argp);
4787 case BTRFS_IOC_INO_LOOKUP_USER:
4788 return btrfs_ioctl_ino_lookup_user(file, argp);
4789 case FS_IOC_ENABLE_VERITY:
4790 return fsverity_ioctl_enable(file, (const void __user *)argp);
4791 case FS_IOC_MEASURE_VERITY:
4792 return fsverity_ioctl_measure(file, argp);
4793 case BTRFS_IOC_ENCODED_READ:
4794 return btrfs_ioctl_encoded_read(file, argp, false);
4795 case BTRFS_IOC_ENCODED_WRITE:
4796 return btrfs_ioctl_encoded_write(file, argp, false);
4797#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4798 case BTRFS_IOC_ENCODED_READ_32:
4799 return btrfs_ioctl_encoded_read(file, argp, true);
4800 case BTRFS_IOC_ENCODED_WRITE_32:
4801 return btrfs_ioctl_encoded_write(file, argp, true);
4802#endif
4803 }
4804
4805 return -ENOTTY;
4806}
4807
4808#ifdef CONFIG_COMPAT
4809long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
4810{
4811 /*
4812 * These all access 32-bit values anyway so no further
4813 * handling is necessary.
4814 */
4815 switch (cmd) {
4816 case FS_IOC32_GETVERSION:
4817 cmd = FS_IOC_GETVERSION;
4818 break;
4819 }
4820
4821 return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
4822}
4823#endif
1/*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19#include <linux/kernel.h>
20#include <linux/bio.h>
21#include <linux/buffer_head.h>
22#include <linux/file.h>
23#include <linux/fs.h>
24#include <linux/fsnotify.h>
25#include <linux/pagemap.h>
26#include <linux/highmem.h>
27#include <linux/time.h>
28#include <linux/init.h>
29#include <linux/string.h>
30#include <linux/backing-dev.h>
31#include <linux/mount.h>
32#include <linux/mpage.h>
33#include <linux/namei.h>
34#include <linux/swap.h>
35#include <linux/writeback.h>
36#include <linux/statfs.h>
37#include <linux/compat.h>
38#include <linux/bit_spinlock.h>
39#include <linux/security.h>
40#include <linux/xattr.h>
41#include <linux/vmalloc.h>
42#include <linux/slab.h>
43#include <linux/blkdev.h>
44#include "compat.h"
45#include "ctree.h"
46#include "disk-io.h"
47#include "transaction.h"
48#include "btrfs_inode.h"
49#include "ioctl.h"
50#include "print-tree.h"
51#include "volumes.h"
52#include "locking.h"
53#include "inode-map.h"
54
55/* Mask out flags that are inappropriate for the given type of inode. */
56static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
57{
58 if (S_ISDIR(mode))
59 return flags;
60 else if (S_ISREG(mode))
61 return flags & ~FS_DIRSYNC_FL;
62 else
63 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
64}
65
66/*
67 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
68 */
69static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
70{
71 unsigned int iflags = 0;
72
73 if (flags & BTRFS_INODE_SYNC)
74 iflags |= FS_SYNC_FL;
75 if (flags & BTRFS_INODE_IMMUTABLE)
76 iflags |= FS_IMMUTABLE_FL;
77 if (flags & BTRFS_INODE_APPEND)
78 iflags |= FS_APPEND_FL;
79 if (flags & BTRFS_INODE_NODUMP)
80 iflags |= FS_NODUMP_FL;
81 if (flags & BTRFS_INODE_NOATIME)
82 iflags |= FS_NOATIME_FL;
83 if (flags & BTRFS_INODE_DIRSYNC)
84 iflags |= FS_DIRSYNC_FL;
85 if (flags & BTRFS_INODE_NODATACOW)
86 iflags |= FS_NOCOW_FL;
87
88 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
89 iflags |= FS_COMPR_FL;
90 else if (flags & BTRFS_INODE_NOCOMPRESS)
91 iflags |= FS_NOCOMP_FL;
92
93 return iflags;
94}
95
96/*
97 * Update inode->i_flags based on the btrfs internal flags.
98 */
99void btrfs_update_iflags(struct inode *inode)
100{
101 struct btrfs_inode *ip = BTRFS_I(inode);
102
103 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
104
105 if (ip->flags & BTRFS_INODE_SYNC)
106 inode->i_flags |= S_SYNC;
107 if (ip->flags & BTRFS_INODE_IMMUTABLE)
108 inode->i_flags |= S_IMMUTABLE;
109 if (ip->flags & BTRFS_INODE_APPEND)
110 inode->i_flags |= S_APPEND;
111 if (ip->flags & BTRFS_INODE_NOATIME)
112 inode->i_flags |= S_NOATIME;
113 if (ip->flags & BTRFS_INODE_DIRSYNC)
114 inode->i_flags |= S_DIRSYNC;
115}
116
117/*
118 * Inherit flags from the parent inode.
119 *
120 * Unlike extN we don't have any flags we don't want to inherit currently.
121 */
122void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
123{
124 unsigned int flags;
125
126 if (!dir)
127 return;
128
129 flags = BTRFS_I(dir)->flags;
130
131 if (S_ISREG(inode->i_mode))
132 flags &= ~BTRFS_INODE_DIRSYNC;
133 else if (!S_ISDIR(inode->i_mode))
134 flags &= (BTRFS_INODE_NODUMP | BTRFS_INODE_NOATIME);
135
136 BTRFS_I(inode)->flags = flags;
137 btrfs_update_iflags(inode);
138}
139
140static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
141{
142 struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
143 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
144
145 if (copy_to_user(arg, &flags, sizeof(flags)))
146 return -EFAULT;
147 return 0;
148}
149
150static int check_flags(unsigned int flags)
151{
152 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
153 FS_NOATIME_FL | FS_NODUMP_FL | \
154 FS_SYNC_FL | FS_DIRSYNC_FL | \
155 FS_NOCOMP_FL | FS_COMPR_FL |
156 FS_NOCOW_FL))
157 return -EOPNOTSUPP;
158
159 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
160 return -EINVAL;
161
162 return 0;
163}
164
165static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
166{
167 struct inode *inode = file->f_path.dentry->d_inode;
168 struct btrfs_inode *ip = BTRFS_I(inode);
169 struct btrfs_root *root = ip->root;
170 struct btrfs_trans_handle *trans;
171 unsigned int flags, oldflags;
172 int ret;
173
174 if (btrfs_root_readonly(root))
175 return -EROFS;
176
177 if (copy_from_user(&flags, arg, sizeof(flags)))
178 return -EFAULT;
179
180 ret = check_flags(flags);
181 if (ret)
182 return ret;
183
184 if (!inode_owner_or_capable(inode))
185 return -EACCES;
186
187 mutex_lock(&inode->i_mutex);
188
189 flags = btrfs_mask_flags(inode->i_mode, flags);
190 oldflags = btrfs_flags_to_ioctl(ip->flags);
191 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
192 if (!capable(CAP_LINUX_IMMUTABLE)) {
193 ret = -EPERM;
194 goto out_unlock;
195 }
196 }
197
198 ret = mnt_want_write(file->f_path.mnt);
199 if (ret)
200 goto out_unlock;
201
202 if (flags & FS_SYNC_FL)
203 ip->flags |= BTRFS_INODE_SYNC;
204 else
205 ip->flags &= ~BTRFS_INODE_SYNC;
206 if (flags & FS_IMMUTABLE_FL)
207 ip->flags |= BTRFS_INODE_IMMUTABLE;
208 else
209 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
210 if (flags & FS_APPEND_FL)
211 ip->flags |= BTRFS_INODE_APPEND;
212 else
213 ip->flags &= ~BTRFS_INODE_APPEND;
214 if (flags & FS_NODUMP_FL)
215 ip->flags |= BTRFS_INODE_NODUMP;
216 else
217 ip->flags &= ~BTRFS_INODE_NODUMP;
218 if (flags & FS_NOATIME_FL)
219 ip->flags |= BTRFS_INODE_NOATIME;
220 else
221 ip->flags &= ~BTRFS_INODE_NOATIME;
222 if (flags & FS_DIRSYNC_FL)
223 ip->flags |= BTRFS_INODE_DIRSYNC;
224 else
225 ip->flags &= ~BTRFS_INODE_DIRSYNC;
226 if (flags & FS_NOCOW_FL)
227 ip->flags |= BTRFS_INODE_NODATACOW;
228 else
229 ip->flags &= ~BTRFS_INODE_NODATACOW;
230
231 /*
232 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
233 * flag may be changed automatically if compression code won't make
234 * things smaller.
235 */
236 if (flags & FS_NOCOMP_FL) {
237 ip->flags &= ~BTRFS_INODE_COMPRESS;
238 ip->flags |= BTRFS_INODE_NOCOMPRESS;
239 } else if (flags & FS_COMPR_FL) {
240 ip->flags |= BTRFS_INODE_COMPRESS;
241 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
242 } else {
243 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
244 }
245
246 trans = btrfs_join_transaction(root);
247 BUG_ON(IS_ERR(trans));
248
249 ret = btrfs_update_inode(trans, root, inode);
250 BUG_ON(ret);
251
252 btrfs_update_iflags(inode);
253 inode->i_ctime = CURRENT_TIME;
254 btrfs_end_transaction(trans, root);
255
256 mnt_drop_write(file->f_path.mnt);
257
258 ret = 0;
259 out_unlock:
260 mutex_unlock(&inode->i_mutex);
261 return ret;
262}
263
264static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
265{
266 struct inode *inode = file->f_path.dentry->d_inode;
267
268 return put_user(inode->i_generation, arg);
269}
270
271static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
272{
273 struct btrfs_root *root = fdentry(file)->d_sb->s_fs_info;
274 struct btrfs_fs_info *fs_info = root->fs_info;
275 struct btrfs_device *device;
276 struct request_queue *q;
277 struct fstrim_range range;
278 u64 minlen = ULLONG_MAX;
279 u64 num_devices = 0;
280 int ret;
281
282 if (!capable(CAP_SYS_ADMIN))
283 return -EPERM;
284
285 rcu_read_lock();
286 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
287 dev_list) {
288 if (!device->bdev)
289 continue;
290 q = bdev_get_queue(device->bdev);
291 if (blk_queue_discard(q)) {
292 num_devices++;
293 minlen = min((u64)q->limits.discard_granularity,
294 minlen);
295 }
296 }
297 rcu_read_unlock();
298 if (!num_devices)
299 return -EOPNOTSUPP;
300
301 if (copy_from_user(&range, arg, sizeof(range)))
302 return -EFAULT;
303
304 range.minlen = max(range.minlen, minlen);
305 ret = btrfs_trim_fs(root, &range);
306 if (ret < 0)
307 return ret;
308
309 if (copy_to_user(arg, &range, sizeof(range)))
310 return -EFAULT;
311
312 return 0;
313}
314
315static noinline int create_subvol(struct btrfs_root *root,
316 struct dentry *dentry,
317 char *name, int namelen,
318 u64 *async_transid)
319{
320 struct btrfs_trans_handle *trans;
321 struct btrfs_key key;
322 struct btrfs_root_item root_item;
323 struct btrfs_inode_item *inode_item;
324 struct extent_buffer *leaf;
325 struct btrfs_root *new_root;
326 struct dentry *parent = dentry->d_parent;
327 struct inode *dir;
328 int ret;
329 int err;
330 u64 objectid;
331 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
332 u64 index = 0;
333
334 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
335 if (ret)
336 return ret;
337
338 dir = parent->d_inode;
339
340 /*
341 * 1 - inode item
342 * 2 - refs
343 * 1 - root item
344 * 2 - dir items
345 */
346 trans = btrfs_start_transaction(root, 6);
347 if (IS_ERR(trans))
348 return PTR_ERR(trans);
349
350 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
351 0, objectid, NULL, 0, 0, 0);
352 if (IS_ERR(leaf)) {
353 ret = PTR_ERR(leaf);
354 goto fail;
355 }
356
357 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
358 btrfs_set_header_bytenr(leaf, leaf->start);
359 btrfs_set_header_generation(leaf, trans->transid);
360 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
361 btrfs_set_header_owner(leaf, objectid);
362
363 write_extent_buffer(leaf, root->fs_info->fsid,
364 (unsigned long)btrfs_header_fsid(leaf),
365 BTRFS_FSID_SIZE);
366 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
367 (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
368 BTRFS_UUID_SIZE);
369 btrfs_mark_buffer_dirty(leaf);
370
371 inode_item = &root_item.inode;
372 memset(inode_item, 0, sizeof(*inode_item));
373 inode_item->generation = cpu_to_le64(1);
374 inode_item->size = cpu_to_le64(3);
375 inode_item->nlink = cpu_to_le32(1);
376 inode_item->nbytes = cpu_to_le64(root->leafsize);
377 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
378
379 root_item.flags = 0;
380 root_item.byte_limit = 0;
381 inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
382
383 btrfs_set_root_bytenr(&root_item, leaf->start);
384 btrfs_set_root_generation(&root_item, trans->transid);
385 btrfs_set_root_level(&root_item, 0);
386 btrfs_set_root_refs(&root_item, 1);
387 btrfs_set_root_used(&root_item, leaf->len);
388 btrfs_set_root_last_snapshot(&root_item, 0);
389
390 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
391 root_item.drop_level = 0;
392
393 btrfs_tree_unlock(leaf);
394 free_extent_buffer(leaf);
395 leaf = NULL;
396
397 btrfs_set_root_dirid(&root_item, new_dirid);
398
399 key.objectid = objectid;
400 key.offset = 0;
401 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
402 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
403 &root_item);
404 if (ret)
405 goto fail;
406
407 key.offset = (u64)-1;
408 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
409 BUG_ON(IS_ERR(new_root));
410
411 btrfs_record_root_in_trans(trans, new_root);
412
413 ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
414 /*
415 * insert the directory item
416 */
417 ret = btrfs_set_inode_index(dir, &index);
418 BUG_ON(ret);
419
420 ret = btrfs_insert_dir_item(trans, root,
421 name, namelen, dir, &key,
422 BTRFS_FT_DIR, index);
423 if (ret)
424 goto fail;
425
426 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
427 ret = btrfs_update_inode(trans, root, dir);
428 BUG_ON(ret);
429
430 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
431 objectid, root->root_key.objectid,
432 btrfs_ino(dir), index, name, namelen);
433
434 BUG_ON(ret);
435
436 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
437fail:
438 if (async_transid) {
439 *async_transid = trans->transid;
440 err = btrfs_commit_transaction_async(trans, root, 1);
441 } else {
442 err = btrfs_commit_transaction(trans, root);
443 }
444 if (err && !ret)
445 ret = err;
446 return ret;
447}
448
449static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
450 char *name, int namelen, u64 *async_transid,
451 bool readonly)
452{
453 struct inode *inode;
454 struct btrfs_pending_snapshot *pending_snapshot;
455 struct btrfs_trans_handle *trans;
456 int ret;
457
458 if (!root->ref_cows)
459 return -EINVAL;
460
461 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
462 if (!pending_snapshot)
463 return -ENOMEM;
464
465 btrfs_init_block_rsv(&pending_snapshot->block_rsv);
466 pending_snapshot->dentry = dentry;
467 pending_snapshot->root = root;
468 pending_snapshot->readonly = readonly;
469
470 trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
471 if (IS_ERR(trans)) {
472 ret = PTR_ERR(trans);
473 goto fail;
474 }
475
476 ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
477 BUG_ON(ret);
478
479 spin_lock(&root->fs_info->trans_lock);
480 list_add(&pending_snapshot->list,
481 &trans->transaction->pending_snapshots);
482 spin_unlock(&root->fs_info->trans_lock);
483 if (async_transid) {
484 *async_transid = trans->transid;
485 ret = btrfs_commit_transaction_async(trans,
486 root->fs_info->extent_root, 1);
487 } else {
488 ret = btrfs_commit_transaction(trans,
489 root->fs_info->extent_root);
490 }
491 BUG_ON(ret);
492
493 ret = pending_snapshot->error;
494 if (ret)
495 goto fail;
496
497 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
498 if (ret)
499 goto fail;
500
501 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
502 if (IS_ERR(inode)) {
503 ret = PTR_ERR(inode);
504 goto fail;
505 }
506 BUG_ON(!inode);
507 d_instantiate(dentry, inode);
508 ret = 0;
509fail:
510 kfree(pending_snapshot);
511 return ret;
512}
513
514/* copy of check_sticky in fs/namei.c()
515* It's inline, so penalty for filesystems that don't use sticky bit is
516* minimal.
517*/
518static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
519{
520 uid_t fsuid = current_fsuid();
521
522 if (!(dir->i_mode & S_ISVTX))
523 return 0;
524 if (inode->i_uid == fsuid)
525 return 0;
526 if (dir->i_uid == fsuid)
527 return 0;
528 return !capable(CAP_FOWNER);
529}
530
531/* copy of may_delete in fs/namei.c()
532 * Check whether we can remove a link victim from directory dir, check
533 * whether the type of victim is right.
534 * 1. We can't do it if dir is read-only (done in permission())
535 * 2. We should have write and exec permissions on dir
536 * 3. We can't remove anything from append-only dir
537 * 4. We can't do anything with immutable dir (done in permission())
538 * 5. If the sticky bit on dir is set we should either
539 * a. be owner of dir, or
540 * b. be owner of victim, or
541 * c. have CAP_FOWNER capability
542 * 6. If the victim is append-only or immutable we can't do antyhing with
543 * links pointing to it.
544 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
545 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
546 * 9. We can't remove a root or mountpoint.
547 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
548 * nfs_async_unlink().
549 */
550
551static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
552{
553 int error;
554
555 if (!victim->d_inode)
556 return -ENOENT;
557
558 BUG_ON(victim->d_parent->d_inode != dir);
559 audit_inode_child(victim, dir);
560
561 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
562 if (error)
563 return error;
564 if (IS_APPEND(dir))
565 return -EPERM;
566 if (btrfs_check_sticky(dir, victim->d_inode)||
567 IS_APPEND(victim->d_inode)||
568 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
569 return -EPERM;
570 if (isdir) {
571 if (!S_ISDIR(victim->d_inode->i_mode))
572 return -ENOTDIR;
573 if (IS_ROOT(victim))
574 return -EBUSY;
575 } else if (S_ISDIR(victim->d_inode->i_mode))
576 return -EISDIR;
577 if (IS_DEADDIR(dir))
578 return -ENOENT;
579 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
580 return -EBUSY;
581 return 0;
582}
583
584/* copy of may_create in fs/namei.c() */
585static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
586{
587 if (child->d_inode)
588 return -EEXIST;
589 if (IS_DEADDIR(dir))
590 return -ENOENT;
591 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
592}
593
594/*
595 * Create a new subvolume below @parent. This is largely modeled after
596 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
597 * inside this filesystem so it's quite a bit simpler.
598 */
599static noinline int btrfs_mksubvol(struct path *parent,
600 char *name, int namelen,
601 struct btrfs_root *snap_src,
602 u64 *async_transid, bool readonly)
603{
604 struct inode *dir = parent->dentry->d_inode;
605 struct dentry *dentry;
606 int error;
607
608 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
609
610 dentry = lookup_one_len(name, parent->dentry, namelen);
611 error = PTR_ERR(dentry);
612 if (IS_ERR(dentry))
613 goto out_unlock;
614
615 error = -EEXIST;
616 if (dentry->d_inode)
617 goto out_dput;
618
619 error = mnt_want_write(parent->mnt);
620 if (error)
621 goto out_dput;
622
623 error = btrfs_may_create(dir, dentry);
624 if (error)
625 goto out_drop_write;
626
627 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
628
629 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
630 goto out_up_read;
631
632 if (snap_src) {
633 error = create_snapshot(snap_src, dentry,
634 name, namelen, async_transid, readonly);
635 } else {
636 error = create_subvol(BTRFS_I(dir)->root, dentry,
637 name, namelen, async_transid);
638 }
639 if (!error)
640 fsnotify_mkdir(dir, dentry);
641out_up_read:
642 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
643out_drop_write:
644 mnt_drop_write(parent->mnt);
645out_dput:
646 dput(dentry);
647out_unlock:
648 mutex_unlock(&dir->i_mutex);
649 return error;
650}
651
652/*
653 * When we're defragging a range, we don't want to kick it off again
654 * if it is really just waiting for delalloc to send it down.
655 * If we find a nice big extent or delalloc range for the bytes in the
656 * file you want to defrag, we return 0 to let you know to skip this
657 * part of the file
658 */
659static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
660{
661 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
662 struct extent_map *em = NULL;
663 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
664 u64 end;
665
666 read_lock(&em_tree->lock);
667 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
668 read_unlock(&em_tree->lock);
669
670 if (em) {
671 end = extent_map_end(em);
672 free_extent_map(em);
673 if (end - offset > thresh)
674 return 0;
675 }
676 /* if we already have a nice delalloc here, just stop */
677 thresh /= 2;
678 end = count_range_bits(io_tree, &offset, offset + thresh,
679 thresh, EXTENT_DELALLOC, 1);
680 if (end >= thresh)
681 return 0;
682 return 1;
683}
684
685/*
686 * helper function to walk through a file and find extents
687 * newer than a specific transid, and smaller than thresh.
688 *
689 * This is used by the defragging code to find new and small
690 * extents
691 */
692static int find_new_extents(struct btrfs_root *root,
693 struct inode *inode, u64 newer_than,
694 u64 *off, int thresh)
695{
696 struct btrfs_path *path;
697 struct btrfs_key min_key;
698 struct btrfs_key max_key;
699 struct extent_buffer *leaf;
700 struct btrfs_file_extent_item *extent;
701 int type;
702 int ret;
703 u64 ino = btrfs_ino(inode);
704
705 path = btrfs_alloc_path();
706 if (!path)
707 return -ENOMEM;
708
709 min_key.objectid = ino;
710 min_key.type = BTRFS_EXTENT_DATA_KEY;
711 min_key.offset = *off;
712
713 max_key.objectid = ino;
714 max_key.type = (u8)-1;
715 max_key.offset = (u64)-1;
716
717 path->keep_locks = 1;
718
719 while(1) {
720 ret = btrfs_search_forward(root, &min_key, &max_key,
721 path, 0, newer_than);
722 if (ret != 0)
723 goto none;
724 if (min_key.objectid != ino)
725 goto none;
726 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
727 goto none;
728
729 leaf = path->nodes[0];
730 extent = btrfs_item_ptr(leaf, path->slots[0],
731 struct btrfs_file_extent_item);
732
733 type = btrfs_file_extent_type(leaf, extent);
734 if (type == BTRFS_FILE_EXTENT_REG &&
735 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
736 check_defrag_in_cache(inode, min_key.offset, thresh)) {
737 *off = min_key.offset;
738 btrfs_free_path(path);
739 return 0;
740 }
741
742 if (min_key.offset == (u64)-1)
743 goto none;
744
745 min_key.offset++;
746 btrfs_release_path(path);
747 }
748none:
749 btrfs_free_path(path);
750 return -ENOENT;
751}
752
753static int should_defrag_range(struct inode *inode, u64 start, u64 len,
754 int thresh, u64 *last_len, u64 *skip,
755 u64 *defrag_end)
756{
757 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
758 struct extent_map *em = NULL;
759 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
760 int ret = 1;
761
762 /*
763 * make sure that once we start defragging and extent, we keep on
764 * defragging it
765 */
766 if (start < *defrag_end)
767 return 1;
768
769 *skip = 0;
770
771 /*
772 * hopefully we have this extent in the tree already, try without
773 * the full extent lock
774 */
775 read_lock(&em_tree->lock);
776 em = lookup_extent_mapping(em_tree, start, len);
777 read_unlock(&em_tree->lock);
778
779 if (!em) {
780 /* get the big lock and read metadata off disk */
781 lock_extent(io_tree, start, start + len - 1, GFP_NOFS);
782 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
783 unlock_extent(io_tree, start, start + len - 1, GFP_NOFS);
784
785 if (IS_ERR(em))
786 return 0;
787 }
788
789 /* this will cover holes, and inline extents */
790 if (em->block_start >= EXTENT_MAP_LAST_BYTE)
791 ret = 0;
792
793 /*
794 * we hit a real extent, if it is big don't bother defragging it again
795 */
796 if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
797 ret = 0;
798
799 /*
800 * last_len ends up being a counter of how many bytes we've defragged.
801 * every time we choose not to defrag an extent, we reset *last_len
802 * so that the next tiny extent will force a defrag.
803 *
804 * The end result of this is that tiny extents before a single big
805 * extent will force at least part of that big extent to be defragged.
806 */
807 if (ret) {
808 *last_len += len;
809 *defrag_end = extent_map_end(em);
810 } else {
811 *last_len = 0;
812 *skip = extent_map_end(em);
813 *defrag_end = 0;
814 }
815
816 free_extent_map(em);
817 return ret;
818}
819
820/*
821 * it doesn't do much good to defrag one or two pages
822 * at a time. This pulls in a nice chunk of pages
823 * to COW and defrag.
824 *
825 * It also makes sure the delalloc code has enough
826 * dirty data to avoid making new small extents as part
827 * of the defrag
828 *
829 * It's a good idea to start RA on this range
830 * before calling this.
831 */
832static int cluster_pages_for_defrag(struct inode *inode,
833 struct page **pages,
834 unsigned long start_index,
835 int num_pages)
836{
837 unsigned long file_end;
838 u64 isize = i_size_read(inode);
839 u64 page_start;
840 u64 page_end;
841 int ret;
842 int i;
843 int i_done;
844 struct btrfs_ordered_extent *ordered;
845 struct extent_state *cached_state = NULL;
846
847 if (isize == 0)
848 return 0;
849 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
850
851 ret = btrfs_delalloc_reserve_space(inode,
852 num_pages << PAGE_CACHE_SHIFT);
853 if (ret)
854 return ret;
855again:
856 ret = 0;
857 i_done = 0;
858
859 /* step one, lock all the pages */
860 for (i = 0; i < num_pages; i++) {
861 struct page *page;
862 page = find_or_create_page(inode->i_mapping,
863 start_index + i, GFP_NOFS);
864 if (!page)
865 break;
866
867 if (!PageUptodate(page)) {
868 btrfs_readpage(NULL, page);
869 lock_page(page);
870 if (!PageUptodate(page)) {
871 unlock_page(page);
872 page_cache_release(page);
873 ret = -EIO;
874 break;
875 }
876 }
877 isize = i_size_read(inode);
878 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
879 if (!isize || page->index > file_end ||
880 page->mapping != inode->i_mapping) {
881 /* whoops, we blew past eof, skip this page */
882 unlock_page(page);
883 page_cache_release(page);
884 break;
885 }
886 pages[i] = page;
887 i_done++;
888 }
889 if (!i_done || ret)
890 goto out;
891
892 if (!(inode->i_sb->s_flags & MS_ACTIVE))
893 goto out;
894
895 /*
896 * so now we have a nice long stream of locked
897 * and up to date pages, lets wait on them
898 */
899 for (i = 0; i < i_done; i++)
900 wait_on_page_writeback(pages[i]);
901
902 page_start = page_offset(pages[0]);
903 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
904
905 lock_extent_bits(&BTRFS_I(inode)->io_tree,
906 page_start, page_end - 1, 0, &cached_state,
907 GFP_NOFS);
908 ordered = btrfs_lookup_first_ordered_extent(inode, page_end - 1);
909 if (ordered &&
910 ordered->file_offset + ordered->len > page_start &&
911 ordered->file_offset < page_end) {
912 btrfs_put_ordered_extent(ordered);
913 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
914 page_start, page_end - 1,
915 &cached_state, GFP_NOFS);
916 for (i = 0; i < i_done; i++) {
917 unlock_page(pages[i]);
918 page_cache_release(pages[i]);
919 }
920 btrfs_wait_ordered_range(inode, page_start,
921 page_end - page_start);
922 goto again;
923 }
924 if (ordered)
925 btrfs_put_ordered_extent(ordered);
926
927 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
928 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
929 EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
930 GFP_NOFS);
931
932 if (i_done != num_pages) {
933 spin_lock(&BTRFS_I(inode)->lock);
934 BTRFS_I(inode)->outstanding_extents++;
935 spin_unlock(&BTRFS_I(inode)->lock);
936 btrfs_delalloc_release_space(inode,
937 (num_pages - i_done) << PAGE_CACHE_SHIFT);
938 }
939
940
941 btrfs_set_extent_delalloc(inode, page_start, page_end - 1,
942 &cached_state);
943
944 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
945 page_start, page_end - 1, &cached_state,
946 GFP_NOFS);
947
948 for (i = 0; i < i_done; i++) {
949 clear_page_dirty_for_io(pages[i]);
950 ClearPageChecked(pages[i]);
951 set_page_extent_mapped(pages[i]);
952 set_page_dirty(pages[i]);
953 unlock_page(pages[i]);
954 page_cache_release(pages[i]);
955 }
956 return i_done;
957out:
958 for (i = 0; i < i_done; i++) {
959 unlock_page(pages[i]);
960 page_cache_release(pages[i]);
961 }
962 btrfs_delalloc_release_space(inode, num_pages << PAGE_CACHE_SHIFT);
963 return ret;
964
965}
966
967int btrfs_defrag_file(struct inode *inode, struct file *file,
968 struct btrfs_ioctl_defrag_range_args *range,
969 u64 newer_than, unsigned long max_to_defrag)
970{
971 struct btrfs_root *root = BTRFS_I(inode)->root;
972 struct btrfs_super_block *disk_super;
973 struct file_ra_state *ra = NULL;
974 unsigned long last_index;
975 u64 features;
976 u64 last_len = 0;
977 u64 skip = 0;
978 u64 defrag_end = 0;
979 u64 newer_off = range->start;
980 int newer_left = 0;
981 unsigned long i;
982 int ret;
983 int defrag_count = 0;
984 int compress_type = BTRFS_COMPRESS_ZLIB;
985 int extent_thresh = range->extent_thresh;
986 int newer_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
987 u64 new_align = ~((u64)128 * 1024 - 1);
988 struct page **pages = NULL;
989
990 if (extent_thresh == 0)
991 extent_thresh = 256 * 1024;
992
993 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
994 if (range->compress_type > BTRFS_COMPRESS_TYPES)
995 return -EINVAL;
996 if (range->compress_type)
997 compress_type = range->compress_type;
998 }
999
1000 if (inode->i_size == 0)
1001 return 0;
1002
1003 /*
1004 * if we were not given a file, allocate a readahead
1005 * context
1006 */
1007 if (!file) {
1008 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1009 if (!ra)
1010 return -ENOMEM;
1011 file_ra_state_init(ra, inode->i_mapping);
1012 } else {
1013 ra = &file->f_ra;
1014 }
1015
1016 pages = kmalloc(sizeof(struct page *) * newer_cluster,
1017 GFP_NOFS);
1018 if (!pages) {
1019 ret = -ENOMEM;
1020 goto out_ra;
1021 }
1022
1023 /* find the last page to defrag */
1024 if (range->start + range->len > range->start) {
1025 last_index = min_t(u64, inode->i_size - 1,
1026 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1027 } else {
1028 last_index = (inode->i_size - 1) >> PAGE_CACHE_SHIFT;
1029 }
1030
1031 if (newer_than) {
1032 ret = find_new_extents(root, inode, newer_than,
1033 &newer_off, 64 * 1024);
1034 if (!ret) {
1035 range->start = newer_off;
1036 /*
1037 * we always align our defrag to help keep
1038 * the extents in the file evenly spaced
1039 */
1040 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1041 newer_left = newer_cluster;
1042 } else
1043 goto out_ra;
1044 } else {
1045 i = range->start >> PAGE_CACHE_SHIFT;
1046 }
1047 if (!max_to_defrag)
1048 max_to_defrag = last_index - 1;
1049
1050 /*
1051 * make writeback starts from i, so the defrag range can be
1052 * written sequentially.
1053 */
1054 if (i < inode->i_mapping->writeback_index)
1055 inode->i_mapping->writeback_index = i;
1056
1057 while (i <= last_index && defrag_count < max_to_defrag &&
1058 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1059 PAGE_CACHE_SHIFT)) {
1060 /*
1061 * make sure we stop running if someone unmounts
1062 * the FS
1063 */
1064 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1065 break;
1066
1067 if (!newer_than &&
1068 !should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1069 PAGE_CACHE_SIZE,
1070 extent_thresh,
1071 &last_len, &skip,
1072 &defrag_end)) {
1073 unsigned long next;
1074 /*
1075 * the should_defrag function tells us how much to skip
1076 * bump our counter by the suggested amount
1077 */
1078 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1079 i = max(i + 1, next);
1080 continue;
1081 }
1082 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1083 BTRFS_I(inode)->force_compress = compress_type;
1084
1085 btrfs_force_ra(inode->i_mapping, ra, file, i, newer_cluster);
1086
1087 ret = cluster_pages_for_defrag(inode, pages, i, newer_cluster);
1088 if (ret < 0)
1089 goto out_ra;
1090
1091 defrag_count += ret;
1092 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
1093 i += ret;
1094
1095 if (newer_than) {
1096 if (newer_off == (u64)-1)
1097 break;
1098
1099 newer_off = max(newer_off + 1,
1100 (u64)i << PAGE_CACHE_SHIFT);
1101
1102 ret = find_new_extents(root, inode,
1103 newer_than, &newer_off,
1104 64 * 1024);
1105 if (!ret) {
1106 range->start = newer_off;
1107 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1108 newer_left = newer_cluster;
1109 } else {
1110 break;
1111 }
1112 } else {
1113 i++;
1114 }
1115 }
1116
1117 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1118 filemap_flush(inode->i_mapping);
1119
1120 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1121 /* the filemap_flush will queue IO into the worker threads, but
1122 * we have to make sure the IO is actually started and that
1123 * ordered extents get created before we return
1124 */
1125 atomic_inc(&root->fs_info->async_submit_draining);
1126 while (atomic_read(&root->fs_info->nr_async_submits) ||
1127 atomic_read(&root->fs_info->async_delalloc_pages)) {
1128 wait_event(root->fs_info->async_submit_wait,
1129 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1130 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1131 }
1132 atomic_dec(&root->fs_info->async_submit_draining);
1133
1134 mutex_lock(&inode->i_mutex);
1135 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1136 mutex_unlock(&inode->i_mutex);
1137 }
1138
1139 disk_super = &root->fs_info->super_copy;
1140 features = btrfs_super_incompat_flags(disk_super);
1141 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1142 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
1143 btrfs_set_super_incompat_flags(disk_super, features);
1144 }
1145
1146 if (!file)
1147 kfree(ra);
1148 return defrag_count;
1149
1150out_ra:
1151 if (!file)
1152 kfree(ra);
1153 kfree(pages);
1154 return ret;
1155}
1156
1157static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
1158 void __user *arg)
1159{
1160 u64 new_size;
1161 u64 old_size;
1162 u64 devid = 1;
1163 struct btrfs_ioctl_vol_args *vol_args;
1164 struct btrfs_trans_handle *trans;
1165 struct btrfs_device *device = NULL;
1166 char *sizestr;
1167 char *devstr = NULL;
1168 int ret = 0;
1169 int mod = 0;
1170
1171 if (root->fs_info->sb->s_flags & MS_RDONLY)
1172 return -EROFS;
1173
1174 if (!capable(CAP_SYS_ADMIN))
1175 return -EPERM;
1176
1177 vol_args = memdup_user(arg, sizeof(*vol_args));
1178 if (IS_ERR(vol_args))
1179 return PTR_ERR(vol_args);
1180
1181 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1182
1183 mutex_lock(&root->fs_info->volume_mutex);
1184 sizestr = vol_args->name;
1185 devstr = strchr(sizestr, ':');
1186 if (devstr) {
1187 char *end;
1188 sizestr = devstr + 1;
1189 *devstr = '\0';
1190 devstr = vol_args->name;
1191 devid = simple_strtoull(devstr, &end, 10);
1192 printk(KERN_INFO "resizing devid %llu\n",
1193 (unsigned long long)devid);
1194 }
1195 device = btrfs_find_device(root, devid, NULL, NULL);
1196 if (!device) {
1197 printk(KERN_INFO "resizer unable to find device %llu\n",
1198 (unsigned long long)devid);
1199 ret = -EINVAL;
1200 goto out_unlock;
1201 }
1202 if (!strcmp(sizestr, "max"))
1203 new_size = device->bdev->bd_inode->i_size;
1204 else {
1205 if (sizestr[0] == '-') {
1206 mod = -1;
1207 sizestr++;
1208 } else if (sizestr[0] == '+') {
1209 mod = 1;
1210 sizestr++;
1211 }
1212 new_size = memparse(sizestr, NULL);
1213 if (new_size == 0) {
1214 ret = -EINVAL;
1215 goto out_unlock;
1216 }
1217 }
1218
1219 old_size = device->total_bytes;
1220
1221 if (mod < 0) {
1222 if (new_size > old_size) {
1223 ret = -EINVAL;
1224 goto out_unlock;
1225 }
1226 new_size = old_size - new_size;
1227 } else if (mod > 0) {
1228 new_size = old_size + new_size;
1229 }
1230
1231 if (new_size < 256 * 1024 * 1024) {
1232 ret = -EINVAL;
1233 goto out_unlock;
1234 }
1235 if (new_size > device->bdev->bd_inode->i_size) {
1236 ret = -EFBIG;
1237 goto out_unlock;
1238 }
1239
1240 do_div(new_size, root->sectorsize);
1241 new_size *= root->sectorsize;
1242
1243 printk(KERN_INFO "new size for %s is %llu\n",
1244 device->name, (unsigned long long)new_size);
1245
1246 if (new_size > old_size) {
1247 trans = btrfs_start_transaction(root, 0);
1248 if (IS_ERR(trans)) {
1249 ret = PTR_ERR(trans);
1250 goto out_unlock;
1251 }
1252 ret = btrfs_grow_device(trans, device, new_size);
1253 btrfs_commit_transaction(trans, root);
1254 } else {
1255 ret = btrfs_shrink_device(device, new_size);
1256 }
1257
1258out_unlock:
1259 mutex_unlock(&root->fs_info->volume_mutex);
1260 kfree(vol_args);
1261 return ret;
1262}
1263
1264static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1265 char *name,
1266 unsigned long fd,
1267 int subvol,
1268 u64 *transid,
1269 bool readonly)
1270{
1271 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1272 struct file *src_file;
1273 int namelen;
1274 int ret = 0;
1275
1276 if (root->fs_info->sb->s_flags & MS_RDONLY)
1277 return -EROFS;
1278
1279 namelen = strlen(name);
1280 if (strchr(name, '/')) {
1281 ret = -EINVAL;
1282 goto out;
1283 }
1284
1285 if (subvol) {
1286 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1287 NULL, transid, readonly);
1288 } else {
1289 struct inode *src_inode;
1290 src_file = fget(fd);
1291 if (!src_file) {
1292 ret = -EINVAL;
1293 goto out;
1294 }
1295
1296 src_inode = src_file->f_path.dentry->d_inode;
1297 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1298 printk(KERN_INFO "btrfs: Snapshot src from "
1299 "another FS\n");
1300 ret = -EINVAL;
1301 fput(src_file);
1302 goto out;
1303 }
1304 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1305 BTRFS_I(src_inode)->root,
1306 transid, readonly);
1307 fput(src_file);
1308 }
1309out:
1310 return ret;
1311}
1312
1313static noinline int btrfs_ioctl_snap_create(struct file *file,
1314 void __user *arg, int subvol)
1315{
1316 struct btrfs_ioctl_vol_args *vol_args;
1317 int ret;
1318
1319 vol_args = memdup_user(arg, sizeof(*vol_args));
1320 if (IS_ERR(vol_args))
1321 return PTR_ERR(vol_args);
1322 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1323
1324 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1325 vol_args->fd, subvol,
1326 NULL, false);
1327
1328 kfree(vol_args);
1329 return ret;
1330}
1331
1332static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1333 void __user *arg, int subvol)
1334{
1335 struct btrfs_ioctl_vol_args_v2 *vol_args;
1336 int ret;
1337 u64 transid = 0;
1338 u64 *ptr = NULL;
1339 bool readonly = false;
1340
1341 vol_args = memdup_user(arg, sizeof(*vol_args));
1342 if (IS_ERR(vol_args))
1343 return PTR_ERR(vol_args);
1344 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1345
1346 if (vol_args->flags &
1347 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
1348 ret = -EOPNOTSUPP;
1349 goto out;
1350 }
1351
1352 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1353 ptr = &transid;
1354 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1355 readonly = true;
1356
1357 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1358 vol_args->fd, subvol,
1359 ptr, readonly);
1360
1361 if (ret == 0 && ptr &&
1362 copy_to_user(arg +
1363 offsetof(struct btrfs_ioctl_vol_args_v2,
1364 transid), ptr, sizeof(*ptr)))
1365 ret = -EFAULT;
1366out:
1367 kfree(vol_args);
1368 return ret;
1369}
1370
1371static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1372 void __user *arg)
1373{
1374 struct inode *inode = fdentry(file)->d_inode;
1375 struct btrfs_root *root = BTRFS_I(inode)->root;
1376 int ret = 0;
1377 u64 flags = 0;
1378
1379 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1380 return -EINVAL;
1381
1382 down_read(&root->fs_info->subvol_sem);
1383 if (btrfs_root_readonly(root))
1384 flags |= BTRFS_SUBVOL_RDONLY;
1385 up_read(&root->fs_info->subvol_sem);
1386
1387 if (copy_to_user(arg, &flags, sizeof(flags)))
1388 ret = -EFAULT;
1389
1390 return ret;
1391}
1392
1393static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1394 void __user *arg)
1395{
1396 struct inode *inode = fdentry(file)->d_inode;
1397 struct btrfs_root *root = BTRFS_I(inode)->root;
1398 struct btrfs_trans_handle *trans;
1399 u64 root_flags;
1400 u64 flags;
1401 int ret = 0;
1402
1403 if (root->fs_info->sb->s_flags & MS_RDONLY)
1404 return -EROFS;
1405
1406 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1407 return -EINVAL;
1408
1409 if (copy_from_user(&flags, arg, sizeof(flags)))
1410 return -EFAULT;
1411
1412 if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
1413 return -EINVAL;
1414
1415 if (flags & ~BTRFS_SUBVOL_RDONLY)
1416 return -EOPNOTSUPP;
1417
1418 if (!inode_owner_or_capable(inode))
1419 return -EACCES;
1420
1421 down_write(&root->fs_info->subvol_sem);
1422
1423 /* nothing to do */
1424 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1425 goto out;
1426
1427 root_flags = btrfs_root_flags(&root->root_item);
1428 if (flags & BTRFS_SUBVOL_RDONLY)
1429 btrfs_set_root_flags(&root->root_item,
1430 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1431 else
1432 btrfs_set_root_flags(&root->root_item,
1433 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1434
1435 trans = btrfs_start_transaction(root, 1);
1436 if (IS_ERR(trans)) {
1437 ret = PTR_ERR(trans);
1438 goto out_reset;
1439 }
1440
1441 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1442 &root->root_key, &root->root_item);
1443
1444 btrfs_commit_transaction(trans, root);
1445out_reset:
1446 if (ret)
1447 btrfs_set_root_flags(&root->root_item, root_flags);
1448out:
1449 up_write(&root->fs_info->subvol_sem);
1450 return ret;
1451}
1452
1453/*
1454 * helper to check if the subvolume references other subvolumes
1455 */
1456static noinline int may_destroy_subvol(struct btrfs_root *root)
1457{
1458 struct btrfs_path *path;
1459 struct btrfs_key key;
1460 int ret;
1461
1462 path = btrfs_alloc_path();
1463 if (!path)
1464 return -ENOMEM;
1465
1466 key.objectid = root->root_key.objectid;
1467 key.type = BTRFS_ROOT_REF_KEY;
1468 key.offset = (u64)-1;
1469
1470 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1471 &key, path, 0, 0);
1472 if (ret < 0)
1473 goto out;
1474 BUG_ON(ret == 0);
1475
1476 ret = 0;
1477 if (path->slots[0] > 0) {
1478 path->slots[0]--;
1479 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1480 if (key.objectid == root->root_key.objectid &&
1481 key.type == BTRFS_ROOT_REF_KEY)
1482 ret = -ENOTEMPTY;
1483 }
1484out:
1485 btrfs_free_path(path);
1486 return ret;
1487}
1488
1489static noinline int key_in_sk(struct btrfs_key *key,
1490 struct btrfs_ioctl_search_key *sk)
1491{
1492 struct btrfs_key test;
1493 int ret;
1494
1495 test.objectid = sk->min_objectid;
1496 test.type = sk->min_type;
1497 test.offset = sk->min_offset;
1498
1499 ret = btrfs_comp_cpu_keys(key, &test);
1500 if (ret < 0)
1501 return 0;
1502
1503 test.objectid = sk->max_objectid;
1504 test.type = sk->max_type;
1505 test.offset = sk->max_offset;
1506
1507 ret = btrfs_comp_cpu_keys(key, &test);
1508 if (ret > 0)
1509 return 0;
1510 return 1;
1511}
1512
1513static noinline int copy_to_sk(struct btrfs_root *root,
1514 struct btrfs_path *path,
1515 struct btrfs_key *key,
1516 struct btrfs_ioctl_search_key *sk,
1517 char *buf,
1518 unsigned long *sk_offset,
1519 int *num_found)
1520{
1521 u64 found_transid;
1522 struct extent_buffer *leaf;
1523 struct btrfs_ioctl_search_header sh;
1524 unsigned long item_off;
1525 unsigned long item_len;
1526 int nritems;
1527 int i;
1528 int slot;
1529 int ret = 0;
1530
1531 leaf = path->nodes[0];
1532 slot = path->slots[0];
1533 nritems = btrfs_header_nritems(leaf);
1534
1535 if (btrfs_header_generation(leaf) > sk->max_transid) {
1536 i = nritems;
1537 goto advance_key;
1538 }
1539 found_transid = btrfs_header_generation(leaf);
1540
1541 for (i = slot; i < nritems; i++) {
1542 item_off = btrfs_item_ptr_offset(leaf, i);
1543 item_len = btrfs_item_size_nr(leaf, i);
1544
1545 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1546 item_len = 0;
1547
1548 if (sizeof(sh) + item_len + *sk_offset >
1549 BTRFS_SEARCH_ARGS_BUFSIZE) {
1550 ret = 1;
1551 goto overflow;
1552 }
1553
1554 btrfs_item_key_to_cpu(leaf, key, i);
1555 if (!key_in_sk(key, sk))
1556 continue;
1557
1558 sh.objectid = key->objectid;
1559 sh.offset = key->offset;
1560 sh.type = key->type;
1561 sh.len = item_len;
1562 sh.transid = found_transid;
1563
1564 /* copy search result header */
1565 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1566 *sk_offset += sizeof(sh);
1567
1568 if (item_len) {
1569 char *p = buf + *sk_offset;
1570 /* copy the item */
1571 read_extent_buffer(leaf, p,
1572 item_off, item_len);
1573 *sk_offset += item_len;
1574 }
1575 (*num_found)++;
1576
1577 if (*num_found >= sk->nr_items)
1578 break;
1579 }
1580advance_key:
1581 ret = 0;
1582 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1583 key->offset++;
1584 else if (key->type < (u8)-1 && key->type < sk->max_type) {
1585 key->offset = 0;
1586 key->type++;
1587 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1588 key->offset = 0;
1589 key->type = 0;
1590 key->objectid++;
1591 } else
1592 ret = 1;
1593overflow:
1594 return ret;
1595}
1596
1597static noinline int search_ioctl(struct inode *inode,
1598 struct btrfs_ioctl_search_args *args)
1599{
1600 struct btrfs_root *root;
1601 struct btrfs_key key;
1602 struct btrfs_key max_key;
1603 struct btrfs_path *path;
1604 struct btrfs_ioctl_search_key *sk = &args->key;
1605 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1606 int ret;
1607 int num_found = 0;
1608 unsigned long sk_offset = 0;
1609
1610 path = btrfs_alloc_path();
1611 if (!path)
1612 return -ENOMEM;
1613
1614 if (sk->tree_id == 0) {
1615 /* search the root of the inode that was passed */
1616 root = BTRFS_I(inode)->root;
1617 } else {
1618 key.objectid = sk->tree_id;
1619 key.type = BTRFS_ROOT_ITEM_KEY;
1620 key.offset = (u64)-1;
1621 root = btrfs_read_fs_root_no_name(info, &key);
1622 if (IS_ERR(root)) {
1623 printk(KERN_ERR "could not find root %llu\n",
1624 sk->tree_id);
1625 btrfs_free_path(path);
1626 return -ENOENT;
1627 }
1628 }
1629
1630 key.objectid = sk->min_objectid;
1631 key.type = sk->min_type;
1632 key.offset = sk->min_offset;
1633
1634 max_key.objectid = sk->max_objectid;
1635 max_key.type = sk->max_type;
1636 max_key.offset = sk->max_offset;
1637
1638 path->keep_locks = 1;
1639
1640 while(1) {
1641 ret = btrfs_search_forward(root, &key, &max_key, path, 0,
1642 sk->min_transid);
1643 if (ret != 0) {
1644 if (ret > 0)
1645 ret = 0;
1646 goto err;
1647 }
1648 ret = copy_to_sk(root, path, &key, sk, args->buf,
1649 &sk_offset, &num_found);
1650 btrfs_release_path(path);
1651 if (ret || num_found >= sk->nr_items)
1652 break;
1653
1654 }
1655 ret = 0;
1656err:
1657 sk->nr_items = num_found;
1658 btrfs_free_path(path);
1659 return ret;
1660}
1661
1662static noinline int btrfs_ioctl_tree_search(struct file *file,
1663 void __user *argp)
1664{
1665 struct btrfs_ioctl_search_args *args;
1666 struct inode *inode;
1667 int ret;
1668
1669 if (!capable(CAP_SYS_ADMIN))
1670 return -EPERM;
1671
1672 args = memdup_user(argp, sizeof(*args));
1673 if (IS_ERR(args))
1674 return PTR_ERR(args);
1675
1676 inode = fdentry(file)->d_inode;
1677 ret = search_ioctl(inode, args);
1678 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1679 ret = -EFAULT;
1680 kfree(args);
1681 return ret;
1682}
1683
1684/*
1685 * Search INODE_REFs to identify path name of 'dirid' directory
1686 * in a 'tree_id' tree. and sets path name to 'name'.
1687 */
1688static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1689 u64 tree_id, u64 dirid, char *name)
1690{
1691 struct btrfs_root *root;
1692 struct btrfs_key key;
1693 char *ptr;
1694 int ret = -1;
1695 int slot;
1696 int len;
1697 int total_len = 0;
1698 struct btrfs_inode_ref *iref;
1699 struct extent_buffer *l;
1700 struct btrfs_path *path;
1701
1702 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1703 name[0]='\0';
1704 return 0;
1705 }
1706
1707 path = btrfs_alloc_path();
1708 if (!path)
1709 return -ENOMEM;
1710
1711 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1712
1713 key.objectid = tree_id;
1714 key.type = BTRFS_ROOT_ITEM_KEY;
1715 key.offset = (u64)-1;
1716 root = btrfs_read_fs_root_no_name(info, &key);
1717 if (IS_ERR(root)) {
1718 printk(KERN_ERR "could not find root %llu\n", tree_id);
1719 ret = -ENOENT;
1720 goto out;
1721 }
1722
1723 key.objectid = dirid;
1724 key.type = BTRFS_INODE_REF_KEY;
1725 key.offset = (u64)-1;
1726
1727 while(1) {
1728 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1729 if (ret < 0)
1730 goto out;
1731
1732 l = path->nodes[0];
1733 slot = path->slots[0];
1734 if (ret > 0 && slot > 0)
1735 slot--;
1736 btrfs_item_key_to_cpu(l, &key, slot);
1737
1738 if (ret > 0 && (key.objectid != dirid ||
1739 key.type != BTRFS_INODE_REF_KEY)) {
1740 ret = -ENOENT;
1741 goto out;
1742 }
1743
1744 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1745 len = btrfs_inode_ref_name_len(l, iref);
1746 ptr -= len + 1;
1747 total_len += len + 1;
1748 if (ptr < name)
1749 goto out;
1750
1751 *(ptr + len) = '/';
1752 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1753
1754 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1755 break;
1756
1757 btrfs_release_path(path);
1758 key.objectid = key.offset;
1759 key.offset = (u64)-1;
1760 dirid = key.objectid;
1761 }
1762 if (ptr < name)
1763 goto out;
1764 memmove(name, ptr, total_len);
1765 name[total_len]='\0';
1766 ret = 0;
1767out:
1768 btrfs_free_path(path);
1769 return ret;
1770}
1771
1772static noinline int btrfs_ioctl_ino_lookup(struct file *file,
1773 void __user *argp)
1774{
1775 struct btrfs_ioctl_ino_lookup_args *args;
1776 struct inode *inode;
1777 int ret;
1778
1779 if (!capable(CAP_SYS_ADMIN))
1780 return -EPERM;
1781
1782 args = memdup_user(argp, sizeof(*args));
1783 if (IS_ERR(args))
1784 return PTR_ERR(args);
1785
1786 inode = fdentry(file)->d_inode;
1787
1788 if (args->treeid == 0)
1789 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
1790
1791 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
1792 args->treeid, args->objectid,
1793 args->name);
1794
1795 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1796 ret = -EFAULT;
1797
1798 kfree(args);
1799 return ret;
1800}
1801
1802static noinline int btrfs_ioctl_snap_destroy(struct file *file,
1803 void __user *arg)
1804{
1805 struct dentry *parent = fdentry(file);
1806 struct dentry *dentry;
1807 struct inode *dir = parent->d_inode;
1808 struct inode *inode;
1809 struct btrfs_root *root = BTRFS_I(dir)->root;
1810 struct btrfs_root *dest = NULL;
1811 struct btrfs_ioctl_vol_args *vol_args;
1812 struct btrfs_trans_handle *trans;
1813 int namelen;
1814 int ret;
1815 int err = 0;
1816
1817 vol_args = memdup_user(arg, sizeof(*vol_args));
1818 if (IS_ERR(vol_args))
1819 return PTR_ERR(vol_args);
1820
1821 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1822 namelen = strlen(vol_args->name);
1823 if (strchr(vol_args->name, '/') ||
1824 strncmp(vol_args->name, "..", namelen) == 0) {
1825 err = -EINVAL;
1826 goto out;
1827 }
1828
1829 err = mnt_want_write(file->f_path.mnt);
1830 if (err)
1831 goto out;
1832
1833 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
1834 dentry = lookup_one_len(vol_args->name, parent, namelen);
1835 if (IS_ERR(dentry)) {
1836 err = PTR_ERR(dentry);
1837 goto out_unlock_dir;
1838 }
1839
1840 if (!dentry->d_inode) {
1841 err = -ENOENT;
1842 goto out_dput;
1843 }
1844
1845 inode = dentry->d_inode;
1846 dest = BTRFS_I(inode)->root;
1847 if (!capable(CAP_SYS_ADMIN)){
1848 /*
1849 * Regular user. Only allow this with a special mount
1850 * option, when the user has write+exec access to the
1851 * subvol root, and when rmdir(2) would have been
1852 * allowed.
1853 *
1854 * Note that this is _not_ check that the subvol is
1855 * empty or doesn't contain data that we wouldn't
1856 * otherwise be able to delete.
1857 *
1858 * Users who want to delete empty subvols should try
1859 * rmdir(2).
1860 */
1861 err = -EPERM;
1862 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
1863 goto out_dput;
1864
1865 /*
1866 * Do not allow deletion if the parent dir is the same
1867 * as the dir to be deleted. That means the ioctl
1868 * must be called on the dentry referencing the root
1869 * of the subvol, not a random directory contained
1870 * within it.
1871 */
1872 err = -EINVAL;
1873 if (root == dest)
1874 goto out_dput;
1875
1876 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
1877 if (err)
1878 goto out_dput;
1879
1880 /* check if subvolume may be deleted by a non-root user */
1881 err = btrfs_may_delete(dir, dentry, 1);
1882 if (err)
1883 goto out_dput;
1884 }
1885
1886 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1887 err = -EINVAL;
1888 goto out_dput;
1889 }
1890
1891 mutex_lock(&inode->i_mutex);
1892 err = d_invalidate(dentry);
1893 if (err)
1894 goto out_unlock;
1895
1896 down_write(&root->fs_info->subvol_sem);
1897
1898 err = may_destroy_subvol(dest);
1899 if (err)
1900 goto out_up_write;
1901
1902 trans = btrfs_start_transaction(root, 0);
1903 if (IS_ERR(trans)) {
1904 err = PTR_ERR(trans);
1905 goto out_up_write;
1906 }
1907 trans->block_rsv = &root->fs_info->global_block_rsv;
1908
1909 ret = btrfs_unlink_subvol(trans, root, dir,
1910 dest->root_key.objectid,
1911 dentry->d_name.name,
1912 dentry->d_name.len);
1913 BUG_ON(ret);
1914
1915 btrfs_record_root_in_trans(trans, dest);
1916
1917 memset(&dest->root_item.drop_progress, 0,
1918 sizeof(dest->root_item.drop_progress));
1919 dest->root_item.drop_level = 0;
1920 btrfs_set_root_refs(&dest->root_item, 0);
1921
1922 if (!xchg(&dest->orphan_item_inserted, 1)) {
1923 ret = btrfs_insert_orphan_item(trans,
1924 root->fs_info->tree_root,
1925 dest->root_key.objectid);
1926 BUG_ON(ret);
1927 }
1928
1929 ret = btrfs_end_transaction(trans, root);
1930 BUG_ON(ret);
1931 inode->i_flags |= S_DEAD;
1932out_up_write:
1933 up_write(&root->fs_info->subvol_sem);
1934out_unlock:
1935 mutex_unlock(&inode->i_mutex);
1936 if (!err) {
1937 shrink_dcache_sb(root->fs_info->sb);
1938 btrfs_invalidate_inodes(dest);
1939 d_delete(dentry);
1940 }
1941out_dput:
1942 dput(dentry);
1943out_unlock_dir:
1944 mutex_unlock(&dir->i_mutex);
1945 mnt_drop_write(file->f_path.mnt);
1946out:
1947 kfree(vol_args);
1948 return err;
1949}
1950
1951static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
1952{
1953 struct inode *inode = fdentry(file)->d_inode;
1954 struct btrfs_root *root = BTRFS_I(inode)->root;
1955 struct btrfs_ioctl_defrag_range_args *range;
1956 int ret;
1957
1958 if (btrfs_root_readonly(root))
1959 return -EROFS;
1960
1961 ret = mnt_want_write(file->f_path.mnt);
1962 if (ret)
1963 return ret;
1964
1965 switch (inode->i_mode & S_IFMT) {
1966 case S_IFDIR:
1967 if (!capable(CAP_SYS_ADMIN)) {
1968 ret = -EPERM;
1969 goto out;
1970 }
1971 ret = btrfs_defrag_root(root, 0);
1972 if (ret)
1973 goto out;
1974 ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
1975 break;
1976 case S_IFREG:
1977 if (!(file->f_mode & FMODE_WRITE)) {
1978 ret = -EINVAL;
1979 goto out;
1980 }
1981
1982 range = kzalloc(sizeof(*range), GFP_KERNEL);
1983 if (!range) {
1984 ret = -ENOMEM;
1985 goto out;
1986 }
1987
1988 if (argp) {
1989 if (copy_from_user(range, argp,
1990 sizeof(*range))) {
1991 ret = -EFAULT;
1992 kfree(range);
1993 goto out;
1994 }
1995 /* compression requires us to start the IO */
1996 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1997 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
1998 range->extent_thresh = (u32)-1;
1999 }
2000 } else {
2001 /* the rest are all set to zero by kzalloc */
2002 range->len = (u64)-1;
2003 }
2004 ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
2005 range, 0, 0);
2006 if (ret > 0)
2007 ret = 0;
2008 kfree(range);
2009 break;
2010 default:
2011 ret = -EINVAL;
2012 }
2013out:
2014 mnt_drop_write(file->f_path.mnt);
2015 return ret;
2016}
2017
2018static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2019{
2020 struct btrfs_ioctl_vol_args *vol_args;
2021 int ret;
2022
2023 if (!capable(CAP_SYS_ADMIN))
2024 return -EPERM;
2025
2026 vol_args = memdup_user(arg, sizeof(*vol_args));
2027 if (IS_ERR(vol_args))
2028 return PTR_ERR(vol_args);
2029
2030 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2031 ret = btrfs_init_new_device(root, vol_args->name);
2032
2033 kfree(vol_args);
2034 return ret;
2035}
2036
2037static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
2038{
2039 struct btrfs_ioctl_vol_args *vol_args;
2040 int ret;
2041
2042 if (!capable(CAP_SYS_ADMIN))
2043 return -EPERM;
2044
2045 if (root->fs_info->sb->s_flags & MS_RDONLY)
2046 return -EROFS;
2047
2048 vol_args = memdup_user(arg, sizeof(*vol_args));
2049 if (IS_ERR(vol_args))
2050 return PTR_ERR(vol_args);
2051
2052 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2053 ret = btrfs_rm_device(root, vol_args->name);
2054
2055 kfree(vol_args);
2056 return ret;
2057}
2058
2059static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2060{
2061 struct btrfs_ioctl_fs_info_args *fi_args;
2062 struct btrfs_device *device;
2063 struct btrfs_device *next;
2064 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2065 int ret = 0;
2066
2067 if (!capable(CAP_SYS_ADMIN))
2068 return -EPERM;
2069
2070 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2071 if (!fi_args)
2072 return -ENOMEM;
2073
2074 fi_args->num_devices = fs_devices->num_devices;
2075 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2076
2077 mutex_lock(&fs_devices->device_list_mutex);
2078 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2079 if (device->devid > fi_args->max_id)
2080 fi_args->max_id = device->devid;
2081 }
2082 mutex_unlock(&fs_devices->device_list_mutex);
2083
2084 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2085 ret = -EFAULT;
2086
2087 kfree(fi_args);
2088 return ret;
2089}
2090
2091static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2092{
2093 struct btrfs_ioctl_dev_info_args *di_args;
2094 struct btrfs_device *dev;
2095 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2096 int ret = 0;
2097 char *s_uuid = NULL;
2098 char empty_uuid[BTRFS_UUID_SIZE] = {0};
2099
2100 if (!capable(CAP_SYS_ADMIN))
2101 return -EPERM;
2102
2103 di_args = memdup_user(arg, sizeof(*di_args));
2104 if (IS_ERR(di_args))
2105 return PTR_ERR(di_args);
2106
2107 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2108 s_uuid = di_args->uuid;
2109
2110 mutex_lock(&fs_devices->device_list_mutex);
2111 dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL);
2112 mutex_unlock(&fs_devices->device_list_mutex);
2113
2114 if (!dev) {
2115 ret = -ENODEV;
2116 goto out;
2117 }
2118
2119 di_args->devid = dev->devid;
2120 di_args->bytes_used = dev->bytes_used;
2121 di_args->total_bytes = dev->total_bytes;
2122 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2123 strncpy(di_args->path, dev->name, sizeof(di_args->path));
2124
2125out:
2126 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2127 ret = -EFAULT;
2128
2129 kfree(di_args);
2130 return ret;
2131}
2132
2133static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2134 u64 off, u64 olen, u64 destoff)
2135{
2136 struct inode *inode = fdentry(file)->d_inode;
2137 struct btrfs_root *root = BTRFS_I(inode)->root;
2138 struct file *src_file;
2139 struct inode *src;
2140 struct btrfs_trans_handle *trans;
2141 struct btrfs_path *path;
2142 struct extent_buffer *leaf;
2143 char *buf;
2144 struct btrfs_key key;
2145 u32 nritems;
2146 int slot;
2147 int ret;
2148 u64 len = olen;
2149 u64 bs = root->fs_info->sb->s_blocksize;
2150 u64 hint_byte;
2151
2152 /*
2153 * TODO:
2154 * - split compressed inline extents. annoying: we need to
2155 * decompress into destination's address_space (the file offset
2156 * may change, so source mapping won't do), then recompress (or
2157 * otherwise reinsert) a subrange.
2158 * - allow ranges within the same file to be cloned (provided
2159 * they don't overlap)?
2160 */
2161
2162 /* the destination must be opened for writing */
2163 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2164 return -EINVAL;
2165
2166 if (btrfs_root_readonly(root))
2167 return -EROFS;
2168
2169 ret = mnt_want_write(file->f_path.mnt);
2170 if (ret)
2171 return ret;
2172
2173 src_file = fget(srcfd);
2174 if (!src_file) {
2175 ret = -EBADF;
2176 goto out_drop_write;
2177 }
2178
2179 src = src_file->f_dentry->d_inode;
2180
2181 ret = -EINVAL;
2182 if (src == inode)
2183 goto out_fput;
2184
2185 /* the src must be open for reading */
2186 if (!(src_file->f_mode & FMODE_READ))
2187 goto out_fput;
2188
2189 /* don't make the dst file partly checksummed */
2190 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2191 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2192 goto out_fput;
2193
2194 ret = -EISDIR;
2195 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2196 goto out_fput;
2197
2198 ret = -EXDEV;
2199 if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
2200 goto out_fput;
2201
2202 ret = -ENOMEM;
2203 buf = vmalloc(btrfs_level_size(root, 0));
2204 if (!buf)
2205 goto out_fput;
2206
2207 path = btrfs_alloc_path();
2208 if (!path) {
2209 vfree(buf);
2210 goto out_fput;
2211 }
2212 path->reada = 2;
2213
2214 if (inode < src) {
2215 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2216 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2217 } else {
2218 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2219 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2220 }
2221
2222 /* determine range to clone */
2223 ret = -EINVAL;
2224 if (off + len > src->i_size || off + len < off)
2225 goto out_unlock;
2226 if (len == 0)
2227 olen = len = src->i_size - off;
2228 /* if we extend to eof, continue to block boundary */
2229 if (off + len == src->i_size)
2230 len = ALIGN(src->i_size, bs) - off;
2231
2232 /* verify the end result is block aligned */
2233 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2234 !IS_ALIGNED(destoff, bs))
2235 goto out_unlock;
2236
2237 if (destoff > inode->i_size) {
2238 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2239 if (ret)
2240 goto out_unlock;
2241 }
2242
2243 /* truncate page cache pages from target inode range */
2244 truncate_inode_pages_range(&inode->i_data, destoff,
2245 PAGE_CACHE_ALIGN(destoff + len) - 1);
2246
2247 /* do any pending delalloc/csum calc on src, one way or
2248 another, and lock file content */
2249 while (1) {
2250 struct btrfs_ordered_extent *ordered;
2251 lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2252 ordered = btrfs_lookup_first_ordered_extent(src, off+len);
2253 if (!ordered &&
2254 !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len,
2255 EXTENT_DELALLOC, 0, NULL))
2256 break;
2257 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2258 if (ordered)
2259 btrfs_put_ordered_extent(ordered);
2260 btrfs_wait_ordered_range(src, off, len);
2261 }
2262
2263 /* clone data */
2264 key.objectid = btrfs_ino(src);
2265 key.type = BTRFS_EXTENT_DATA_KEY;
2266 key.offset = 0;
2267
2268 while (1) {
2269 /*
2270 * note the key will change type as we walk through the
2271 * tree.
2272 */
2273 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2274 if (ret < 0)
2275 goto out;
2276
2277 nritems = btrfs_header_nritems(path->nodes[0]);
2278 if (path->slots[0] >= nritems) {
2279 ret = btrfs_next_leaf(root, path);
2280 if (ret < 0)
2281 goto out;
2282 if (ret > 0)
2283 break;
2284 nritems = btrfs_header_nritems(path->nodes[0]);
2285 }
2286 leaf = path->nodes[0];
2287 slot = path->slots[0];
2288
2289 btrfs_item_key_to_cpu(leaf, &key, slot);
2290 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2291 key.objectid != btrfs_ino(src))
2292 break;
2293
2294 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2295 struct btrfs_file_extent_item *extent;
2296 int type;
2297 u32 size;
2298 struct btrfs_key new_key;
2299 u64 disko = 0, diskl = 0;
2300 u64 datao = 0, datal = 0;
2301 u8 comp;
2302 u64 endoff;
2303
2304 size = btrfs_item_size_nr(leaf, slot);
2305 read_extent_buffer(leaf, buf,
2306 btrfs_item_ptr_offset(leaf, slot),
2307 size);
2308
2309 extent = btrfs_item_ptr(leaf, slot,
2310 struct btrfs_file_extent_item);
2311 comp = btrfs_file_extent_compression(leaf, extent);
2312 type = btrfs_file_extent_type(leaf, extent);
2313 if (type == BTRFS_FILE_EXTENT_REG ||
2314 type == BTRFS_FILE_EXTENT_PREALLOC) {
2315 disko = btrfs_file_extent_disk_bytenr(leaf,
2316 extent);
2317 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2318 extent);
2319 datao = btrfs_file_extent_offset(leaf, extent);
2320 datal = btrfs_file_extent_num_bytes(leaf,
2321 extent);
2322 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2323 /* take upper bound, may be compressed */
2324 datal = btrfs_file_extent_ram_bytes(leaf,
2325 extent);
2326 }
2327 btrfs_release_path(path);
2328
2329 if (key.offset + datal <= off ||
2330 key.offset >= off+len)
2331 goto next;
2332
2333 memcpy(&new_key, &key, sizeof(new_key));
2334 new_key.objectid = btrfs_ino(inode);
2335 if (off <= key.offset)
2336 new_key.offset = key.offset + destoff - off;
2337 else
2338 new_key.offset = destoff;
2339
2340 /*
2341 * 1 - adjusting old extent (we may have to split it)
2342 * 1 - add new extent
2343 * 1 - inode update
2344 */
2345 trans = btrfs_start_transaction(root, 3);
2346 if (IS_ERR(trans)) {
2347 ret = PTR_ERR(trans);
2348 goto out;
2349 }
2350
2351 if (type == BTRFS_FILE_EXTENT_REG ||
2352 type == BTRFS_FILE_EXTENT_PREALLOC) {
2353 /*
2354 * a | --- range to clone ---| b
2355 * | ------------- extent ------------- |
2356 */
2357
2358 /* substract range b */
2359 if (key.offset + datal > off + len)
2360 datal = off + len - key.offset;
2361
2362 /* substract range a */
2363 if (off > key.offset) {
2364 datao += off - key.offset;
2365 datal -= off - key.offset;
2366 }
2367
2368 ret = btrfs_drop_extents(trans, inode,
2369 new_key.offset,
2370 new_key.offset + datal,
2371 &hint_byte, 1);
2372 BUG_ON(ret);
2373
2374 ret = btrfs_insert_empty_item(trans, root, path,
2375 &new_key, size);
2376 BUG_ON(ret);
2377
2378 leaf = path->nodes[0];
2379 slot = path->slots[0];
2380 write_extent_buffer(leaf, buf,
2381 btrfs_item_ptr_offset(leaf, slot),
2382 size);
2383
2384 extent = btrfs_item_ptr(leaf, slot,
2385 struct btrfs_file_extent_item);
2386
2387 /* disko == 0 means it's a hole */
2388 if (!disko)
2389 datao = 0;
2390
2391 btrfs_set_file_extent_offset(leaf, extent,
2392 datao);
2393 btrfs_set_file_extent_num_bytes(leaf, extent,
2394 datal);
2395 if (disko) {
2396 inode_add_bytes(inode, datal);
2397 ret = btrfs_inc_extent_ref(trans, root,
2398 disko, diskl, 0,
2399 root->root_key.objectid,
2400 btrfs_ino(inode),
2401 new_key.offset - datao);
2402 BUG_ON(ret);
2403 }
2404 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2405 u64 skip = 0;
2406 u64 trim = 0;
2407 if (off > key.offset) {
2408 skip = off - key.offset;
2409 new_key.offset += skip;
2410 }
2411
2412 if (key.offset + datal > off+len)
2413 trim = key.offset + datal - (off+len);
2414
2415 if (comp && (skip || trim)) {
2416 ret = -EINVAL;
2417 btrfs_end_transaction(trans, root);
2418 goto out;
2419 }
2420 size -= skip + trim;
2421 datal -= skip + trim;
2422
2423 ret = btrfs_drop_extents(trans, inode,
2424 new_key.offset,
2425 new_key.offset + datal,
2426 &hint_byte, 1);
2427 BUG_ON(ret);
2428
2429 ret = btrfs_insert_empty_item(trans, root, path,
2430 &new_key, size);
2431 BUG_ON(ret);
2432
2433 if (skip) {
2434 u32 start =
2435 btrfs_file_extent_calc_inline_size(0);
2436 memmove(buf+start, buf+start+skip,
2437 datal);
2438 }
2439
2440 leaf = path->nodes[0];
2441 slot = path->slots[0];
2442 write_extent_buffer(leaf, buf,
2443 btrfs_item_ptr_offset(leaf, slot),
2444 size);
2445 inode_add_bytes(inode, datal);
2446 }
2447
2448 btrfs_mark_buffer_dirty(leaf);
2449 btrfs_release_path(path);
2450
2451 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2452
2453 /*
2454 * we round up to the block size at eof when
2455 * determining which extents to clone above,
2456 * but shouldn't round up the file size
2457 */
2458 endoff = new_key.offset + datal;
2459 if (endoff > destoff+olen)
2460 endoff = destoff+olen;
2461 if (endoff > inode->i_size)
2462 btrfs_i_size_write(inode, endoff);
2463
2464 ret = btrfs_update_inode(trans, root, inode);
2465 BUG_ON(ret);
2466 btrfs_end_transaction(trans, root);
2467 }
2468next:
2469 btrfs_release_path(path);
2470 key.offset++;
2471 }
2472 ret = 0;
2473out:
2474 btrfs_release_path(path);
2475 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2476out_unlock:
2477 mutex_unlock(&src->i_mutex);
2478 mutex_unlock(&inode->i_mutex);
2479 vfree(buf);
2480 btrfs_free_path(path);
2481out_fput:
2482 fput(src_file);
2483out_drop_write:
2484 mnt_drop_write(file->f_path.mnt);
2485 return ret;
2486}
2487
2488static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2489{
2490 struct btrfs_ioctl_clone_range_args args;
2491
2492 if (copy_from_user(&args, argp, sizeof(args)))
2493 return -EFAULT;
2494 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2495 args.src_length, args.dest_offset);
2496}
2497
2498/*
2499 * there are many ways the trans_start and trans_end ioctls can lead
2500 * to deadlocks. They should only be used by applications that
2501 * basically own the machine, and have a very in depth understanding
2502 * of all the possible deadlocks and enospc problems.
2503 */
2504static long btrfs_ioctl_trans_start(struct file *file)
2505{
2506 struct inode *inode = fdentry(file)->d_inode;
2507 struct btrfs_root *root = BTRFS_I(inode)->root;
2508 struct btrfs_trans_handle *trans;
2509 int ret;
2510
2511 ret = -EPERM;
2512 if (!capable(CAP_SYS_ADMIN))
2513 goto out;
2514
2515 ret = -EINPROGRESS;
2516 if (file->private_data)
2517 goto out;
2518
2519 ret = -EROFS;
2520 if (btrfs_root_readonly(root))
2521 goto out;
2522
2523 ret = mnt_want_write(file->f_path.mnt);
2524 if (ret)
2525 goto out;
2526
2527 atomic_inc(&root->fs_info->open_ioctl_trans);
2528
2529 ret = -ENOMEM;
2530 trans = btrfs_start_ioctl_transaction(root);
2531 if (IS_ERR(trans))
2532 goto out_drop;
2533
2534 file->private_data = trans;
2535 return 0;
2536
2537out_drop:
2538 atomic_dec(&root->fs_info->open_ioctl_trans);
2539 mnt_drop_write(file->f_path.mnt);
2540out:
2541 return ret;
2542}
2543
2544static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2545{
2546 struct inode *inode = fdentry(file)->d_inode;
2547 struct btrfs_root *root = BTRFS_I(inode)->root;
2548 struct btrfs_root *new_root;
2549 struct btrfs_dir_item *di;
2550 struct btrfs_trans_handle *trans;
2551 struct btrfs_path *path;
2552 struct btrfs_key location;
2553 struct btrfs_disk_key disk_key;
2554 struct btrfs_super_block *disk_super;
2555 u64 features;
2556 u64 objectid = 0;
2557 u64 dir_id;
2558
2559 if (!capable(CAP_SYS_ADMIN))
2560 return -EPERM;
2561
2562 if (copy_from_user(&objectid, argp, sizeof(objectid)))
2563 return -EFAULT;
2564
2565 if (!objectid)
2566 objectid = root->root_key.objectid;
2567
2568 location.objectid = objectid;
2569 location.type = BTRFS_ROOT_ITEM_KEY;
2570 location.offset = (u64)-1;
2571
2572 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2573 if (IS_ERR(new_root))
2574 return PTR_ERR(new_root);
2575
2576 if (btrfs_root_refs(&new_root->root_item) == 0)
2577 return -ENOENT;
2578
2579 path = btrfs_alloc_path();
2580 if (!path)
2581 return -ENOMEM;
2582 path->leave_spinning = 1;
2583
2584 trans = btrfs_start_transaction(root, 1);
2585 if (IS_ERR(trans)) {
2586 btrfs_free_path(path);
2587 return PTR_ERR(trans);
2588 }
2589
2590 dir_id = btrfs_super_root_dir(&root->fs_info->super_copy);
2591 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2592 dir_id, "default", 7, 1);
2593 if (IS_ERR_OR_NULL(di)) {
2594 btrfs_free_path(path);
2595 btrfs_end_transaction(trans, root);
2596 printk(KERN_ERR "Umm, you don't have the default dir item, "
2597 "this isn't going to work\n");
2598 return -ENOENT;
2599 }
2600
2601 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2602 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2603 btrfs_mark_buffer_dirty(path->nodes[0]);
2604 btrfs_free_path(path);
2605
2606 disk_super = &root->fs_info->super_copy;
2607 features = btrfs_super_incompat_flags(disk_super);
2608 if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) {
2609 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL;
2610 btrfs_set_super_incompat_flags(disk_super, features);
2611 }
2612 btrfs_end_transaction(trans, root);
2613
2614 return 0;
2615}
2616
2617static void get_block_group_info(struct list_head *groups_list,
2618 struct btrfs_ioctl_space_info *space)
2619{
2620 struct btrfs_block_group_cache *block_group;
2621
2622 space->total_bytes = 0;
2623 space->used_bytes = 0;
2624 space->flags = 0;
2625 list_for_each_entry(block_group, groups_list, list) {
2626 space->flags = block_group->flags;
2627 space->total_bytes += block_group->key.offset;
2628 space->used_bytes +=
2629 btrfs_block_group_used(&block_group->item);
2630 }
2631}
2632
2633long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
2634{
2635 struct btrfs_ioctl_space_args space_args;
2636 struct btrfs_ioctl_space_info space;
2637 struct btrfs_ioctl_space_info *dest;
2638 struct btrfs_ioctl_space_info *dest_orig;
2639 struct btrfs_ioctl_space_info __user *user_dest;
2640 struct btrfs_space_info *info;
2641 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2642 BTRFS_BLOCK_GROUP_SYSTEM,
2643 BTRFS_BLOCK_GROUP_METADATA,
2644 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
2645 int num_types = 4;
2646 int alloc_size;
2647 int ret = 0;
2648 u64 slot_count = 0;
2649 int i, c;
2650
2651 if (copy_from_user(&space_args,
2652 (struct btrfs_ioctl_space_args __user *)arg,
2653 sizeof(space_args)))
2654 return -EFAULT;
2655
2656 for (i = 0; i < num_types; i++) {
2657 struct btrfs_space_info *tmp;
2658
2659 info = NULL;
2660 rcu_read_lock();
2661 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2662 list) {
2663 if (tmp->flags == types[i]) {
2664 info = tmp;
2665 break;
2666 }
2667 }
2668 rcu_read_unlock();
2669
2670 if (!info)
2671 continue;
2672
2673 down_read(&info->groups_sem);
2674 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2675 if (!list_empty(&info->block_groups[c]))
2676 slot_count++;
2677 }
2678 up_read(&info->groups_sem);
2679 }
2680
2681 /* space_slots == 0 means they are asking for a count */
2682 if (space_args.space_slots == 0) {
2683 space_args.total_spaces = slot_count;
2684 goto out;
2685 }
2686
2687 slot_count = min_t(u64, space_args.space_slots, slot_count);
2688
2689 alloc_size = sizeof(*dest) * slot_count;
2690
2691 /* we generally have at most 6 or so space infos, one for each raid
2692 * level. So, a whole page should be more than enough for everyone
2693 */
2694 if (alloc_size > PAGE_CACHE_SIZE)
2695 return -ENOMEM;
2696
2697 space_args.total_spaces = 0;
2698 dest = kmalloc(alloc_size, GFP_NOFS);
2699 if (!dest)
2700 return -ENOMEM;
2701 dest_orig = dest;
2702
2703 /* now we have a buffer to copy into */
2704 for (i = 0; i < num_types; i++) {
2705 struct btrfs_space_info *tmp;
2706
2707 if (!slot_count)
2708 break;
2709
2710 info = NULL;
2711 rcu_read_lock();
2712 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2713 list) {
2714 if (tmp->flags == types[i]) {
2715 info = tmp;
2716 break;
2717 }
2718 }
2719 rcu_read_unlock();
2720
2721 if (!info)
2722 continue;
2723 down_read(&info->groups_sem);
2724 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2725 if (!list_empty(&info->block_groups[c])) {
2726 get_block_group_info(&info->block_groups[c],
2727 &space);
2728 memcpy(dest, &space, sizeof(space));
2729 dest++;
2730 space_args.total_spaces++;
2731 slot_count--;
2732 }
2733 if (!slot_count)
2734 break;
2735 }
2736 up_read(&info->groups_sem);
2737 }
2738
2739 user_dest = (struct btrfs_ioctl_space_info *)
2740 (arg + sizeof(struct btrfs_ioctl_space_args));
2741
2742 if (copy_to_user(user_dest, dest_orig, alloc_size))
2743 ret = -EFAULT;
2744
2745 kfree(dest_orig);
2746out:
2747 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
2748 ret = -EFAULT;
2749
2750 return ret;
2751}
2752
2753/*
2754 * there are many ways the trans_start and trans_end ioctls can lead
2755 * to deadlocks. They should only be used by applications that
2756 * basically own the machine, and have a very in depth understanding
2757 * of all the possible deadlocks and enospc problems.
2758 */
2759long btrfs_ioctl_trans_end(struct file *file)
2760{
2761 struct inode *inode = fdentry(file)->d_inode;
2762 struct btrfs_root *root = BTRFS_I(inode)->root;
2763 struct btrfs_trans_handle *trans;
2764
2765 trans = file->private_data;
2766 if (!trans)
2767 return -EINVAL;
2768 file->private_data = NULL;
2769
2770 btrfs_end_transaction(trans, root);
2771
2772 atomic_dec(&root->fs_info->open_ioctl_trans);
2773
2774 mnt_drop_write(file->f_path.mnt);
2775 return 0;
2776}
2777
2778static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
2779{
2780 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2781 struct btrfs_trans_handle *trans;
2782 u64 transid;
2783 int ret;
2784
2785 trans = btrfs_start_transaction(root, 0);
2786 if (IS_ERR(trans))
2787 return PTR_ERR(trans);
2788 transid = trans->transid;
2789 ret = btrfs_commit_transaction_async(trans, root, 0);
2790 if (ret) {
2791 btrfs_end_transaction(trans, root);
2792 return ret;
2793 }
2794
2795 if (argp)
2796 if (copy_to_user(argp, &transid, sizeof(transid)))
2797 return -EFAULT;
2798 return 0;
2799}
2800
2801static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
2802{
2803 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2804 u64 transid;
2805
2806 if (argp) {
2807 if (copy_from_user(&transid, argp, sizeof(transid)))
2808 return -EFAULT;
2809 } else {
2810 transid = 0; /* current trans */
2811 }
2812 return btrfs_wait_for_commit(root, transid);
2813}
2814
2815static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg)
2816{
2817 int ret;
2818 struct btrfs_ioctl_scrub_args *sa;
2819
2820 if (!capable(CAP_SYS_ADMIN))
2821 return -EPERM;
2822
2823 sa = memdup_user(arg, sizeof(*sa));
2824 if (IS_ERR(sa))
2825 return PTR_ERR(sa);
2826
2827 ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end,
2828 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY);
2829
2830 if (copy_to_user(arg, sa, sizeof(*sa)))
2831 ret = -EFAULT;
2832
2833 kfree(sa);
2834 return ret;
2835}
2836
2837static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
2838{
2839 if (!capable(CAP_SYS_ADMIN))
2840 return -EPERM;
2841
2842 return btrfs_scrub_cancel(root);
2843}
2844
2845static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
2846 void __user *arg)
2847{
2848 struct btrfs_ioctl_scrub_args *sa;
2849 int ret;
2850
2851 if (!capable(CAP_SYS_ADMIN))
2852 return -EPERM;
2853
2854 sa = memdup_user(arg, sizeof(*sa));
2855 if (IS_ERR(sa))
2856 return PTR_ERR(sa);
2857
2858 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
2859
2860 if (copy_to_user(arg, sa, sizeof(*sa)))
2861 ret = -EFAULT;
2862
2863 kfree(sa);
2864 return ret;
2865}
2866
2867long btrfs_ioctl(struct file *file, unsigned int
2868 cmd, unsigned long arg)
2869{
2870 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2871 void __user *argp = (void __user *)arg;
2872
2873 switch (cmd) {
2874 case FS_IOC_GETFLAGS:
2875 return btrfs_ioctl_getflags(file, argp);
2876 case FS_IOC_SETFLAGS:
2877 return btrfs_ioctl_setflags(file, argp);
2878 case FS_IOC_GETVERSION:
2879 return btrfs_ioctl_getversion(file, argp);
2880 case FITRIM:
2881 return btrfs_ioctl_fitrim(file, argp);
2882 case BTRFS_IOC_SNAP_CREATE:
2883 return btrfs_ioctl_snap_create(file, argp, 0);
2884 case BTRFS_IOC_SNAP_CREATE_V2:
2885 return btrfs_ioctl_snap_create_v2(file, argp, 0);
2886 case BTRFS_IOC_SUBVOL_CREATE:
2887 return btrfs_ioctl_snap_create(file, argp, 1);
2888 case BTRFS_IOC_SNAP_DESTROY:
2889 return btrfs_ioctl_snap_destroy(file, argp);
2890 case BTRFS_IOC_SUBVOL_GETFLAGS:
2891 return btrfs_ioctl_subvol_getflags(file, argp);
2892 case BTRFS_IOC_SUBVOL_SETFLAGS:
2893 return btrfs_ioctl_subvol_setflags(file, argp);
2894 case BTRFS_IOC_DEFAULT_SUBVOL:
2895 return btrfs_ioctl_default_subvol(file, argp);
2896 case BTRFS_IOC_DEFRAG:
2897 return btrfs_ioctl_defrag(file, NULL);
2898 case BTRFS_IOC_DEFRAG_RANGE:
2899 return btrfs_ioctl_defrag(file, argp);
2900 case BTRFS_IOC_RESIZE:
2901 return btrfs_ioctl_resize(root, argp);
2902 case BTRFS_IOC_ADD_DEV:
2903 return btrfs_ioctl_add_dev(root, argp);
2904 case BTRFS_IOC_RM_DEV:
2905 return btrfs_ioctl_rm_dev(root, argp);
2906 case BTRFS_IOC_FS_INFO:
2907 return btrfs_ioctl_fs_info(root, argp);
2908 case BTRFS_IOC_DEV_INFO:
2909 return btrfs_ioctl_dev_info(root, argp);
2910 case BTRFS_IOC_BALANCE:
2911 return btrfs_balance(root->fs_info->dev_root);
2912 case BTRFS_IOC_CLONE:
2913 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
2914 case BTRFS_IOC_CLONE_RANGE:
2915 return btrfs_ioctl_clone_range(file, argp);
2916 case BTRFS_IOC_TRANS_START:
2917 return btrfs_ioctl_trans_start(file);
2918 case BTRFS_IOC_TRANS_END:
2919 return btrfs_ioctl_trans_end(file);
2920 case BTRFS_IOC_TREE_SEARCH:
2921 return btrfs_ioctl_tree_search(file, argp);
2922 case BTRFS_IOC_INO_LOOKUP:
2923 return btrfs_ioctl_ino_lookup(file, argp);
2924 case BTRFS_IOC_SPACE_INFO:
2925 return btrfs_ioctl_space_info(root, argp);
2926 case BTRFS_IOC_SYNC:
2927 btrfs_sync_fs(file->f_dentry->d_sb, 1);
2928 return 0;
2929 case BTRFS_IOC_START_SYNC:
2930 return btrfs_ioctl_start_sync(file, argp);
2931 case BTRFS_IOC_WAIT_SYNC:
2932 return btrfs_ioctl_wait_sync(file, argp);
2933 case BTRFS_IOC_SCRUB:
2934 return btrfs_ioctl_scrub(root, argp);
2935 case BTRFS_IOC_SCRUB_CANCEL:
2936 return btrfs_ioctl_scrub_cancel(root, argp);
2937 case BTRFS_IOC_SCRUB_PROGRESS:
2938 return btrfs_ioctl_scrub_progress(root, argp);
2939 }
2940
2941 return -ENOTTY;
2942}