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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 "ctree.h"
30#include "disk-io.h"
31#include "export.h"
32#include "transaction.h"
33#include "btrfs_inode.h"
34#include "print-tree.h"
35#include "volumes.h"
36#include "locking.h"
37#include "inode-map.h"
38#include "backref.h"
39#include "rcu-string.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 "delalloc-space.h"
49#include "block-group.h"
50
51#ifdef CONFIG_64BIT
52/* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
53 * structures are incorrect, as the timespec structure from userspace
54 * is 4 bytes too small. We define these alternatives here to teach
55 * the kernel about the 32-bit struct packing.
56 */
57struct btrfs_ioctl_timespec_32 {
58 __u64 sec;
59 __u32 nsec;
60} __attribute__ ((__packed__));
61
62struct btrfs_ioctl_received_subvol_args_32 {
63 char uuid[BTRFS_UUID_SIZE]; /* in */
64 __u64 stransid; /* in */
65 __u64 rtransid; /* out */
66 struct btrfs_ioctl_timespec_32 stime; /* in */
67 struct btrfs_ioctl_timespec_32 rtime; /* out */
68 __u64 flags; /* in */
69 __u64 reserved[16]; /* in */
70} __attribute__ ((__packed__));
71
72#define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
73 struct btrfs_ioctl_received_subvol_args_32)
74#endif
75
76#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
77struct btrfs_ioctl_send_args_32 {
78 __s64 send_fd; /* in */
79 __u64 clone_sources_count; /* in */
80 compat_uptr_t clone_sources; /* in */
81 __u64 parent_root; /* in */
82 __u64 flags; /* in */
83 __u64 reserved[4]; /* in */
84} __attribute__ ((__packed__));
85
86#define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \
87 struct btrfs_ioctl_send_args_32)
88#endif
89
90/* Mask out flags that are inappropriate for the given type of inode. */
91static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,
92 unsigned int flags)
93{
94 if (S_ISDIR(inode->i_mode))
95 return flags;
96 else if (S_ISREG(inode->i_mode))
97 return flags & ~FS_DIRSYNC_FL;
98 else
99 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
100}
101
102/*
103 * Export internal inode flags to the format expected by the FS_IOC_GETFLAGS
104 * ioctl.
105 */
106static unsigned int btrfs_inode_flags_to_fsflags(unsigned int flags)
107{
108 unsigned int iflags = 0;
109
110 if (flags & BTRFS_INODE_SYNC)
111 iflags |= FS_SYNC_FL;
112 if (flags & BTRFS_INODE_IMMUTABLE)
113 iflags |= FS_IMMUTABLE_FL;
114 if (flags & BTRFS_INODE_APPEND)
115 iflags |= FS_APPEND_FL;
116 if (flags & BTRFS_INODE_NODUMP)
117 iflags |= FS_NODUMP_FL;
118 if (flags & BTRFS_INODE_NOATIME)
119 iflags |= FS_NOATIME_FL;
120 if (flags & BTRFS_INODE_DIRSYNC)
121 iflags |= FS_DIRSYNC_FL;
122 if (flags & BTRFS_INODE_NODATACOW)
123 iflags |= FS_NOCOW_FL;
124
125 if (flags & BTRFS_INODE_NOCOMPRESS)
126 iflags |= FS_NOCOMP_FL;
127 else if (flags & BTRFS_INODE_COMPRESS)
128 iflags |= FS_COMPR_FL;
129
130 return iflags;
131}
132
133/*
134 * Update inode->i_flags based on the btrfs internal flags.
135 */
136void btrfs_sync_inode_flags_to_i_flags(struct inode *inode)
137{
138 struct btrfs_inode *binode = BTRFS_I(inode);
139 unsigned int new_fl = 0;
140
141 if (binode->flags & BTRFS_INODE_SYNC)
142 new_fl |= S_SYNC;
143 if (binode->flags & BTRFS_INODE_IMMUTABLE)
144 new_fl |= S_IMMUTABLE;
145 if (binode->flags & BTRFS_INODE_APPEND)
146 new_fl |= S_APPEND;
147 if (binode->flags & BTRFS_INODE_NOATIME)
148 new_fl |= S_NOATIME;
149 if (binode->flags & BTRFS_INODE_DIRSYNC)
150 new_fl |= S_DIRSYNC;
151
152 set_mask_bits(&inode->i_flags,
153 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
154 new_fl);
155}
156
157static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
158{
159 struct btrfs_inode *binode = BTRFS_I(file_inode(file));
160 unsigned int flags = btrfs_inode_flags_to_fsflags(binode->flags);
161
162 if (copy_to_user(arg, &flags, sizeof(flags)))
163 return -EFAULT;
164 return 0;
165}
166
167/*
168 * Check if @flags are a supported and valid set of FS_*_FL flags and that
169 * the old and new flags are not conflicting
170 */
171static int check_fsflags(unsigned int old_flags, unsigned int flags)
172{
173 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
174 FS_NOATIME_FL | FS_NODUMP_FL | \
175 FS_SYNC_FL | FS_DIRSYNC_FL | \
176 FS_NOCOMP_FL | FS_COMPR_FL |
177 FS_NOCOW_FL))
178 return -EOPNOTSUPP;
179
180 /* COMPR and NOCOMP on new/old are valid */
181 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
182 return -EINVAL;
183
184 if ((flags & FS_COMPR_FL) && (flags & FS_NOCOW_FL))
185 return -EINVAL;
186
187 /* NOCOW and compression options are mutually exclusive */
188 if ((old_flags & FS_NOCOW_FL) && (flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
189 return -EINVAL;
190 if ((flags & FS_NOCOW_FL) && (old_flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
191 return -EINVAL;
192
193 return 0;
194}
195
196static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
197{
198 struct inode *inode = file_inode(file);
199 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
200 struct btrfs_inode *binode = BTRFS_I(inode);
201 struct btrfs_root *root = binode->root;
202 struct btrfs_trans_handle *trans;
203 unsigned int fsflags, old_fsflags;
204 int ret;
205 const char *comp = NULL;
206 u32 binode_flags;
207
208 if (!inode_owner_or_capable(inode))
209 return -EPERM;
210
211 if (btrfs_root_readonly(root))
212 return -EROFS;
213
214 if (copy_from_user(&fsflags, arg, sizeof(fsflags)))
215 return -EFAULT;
216
217 ret = mnt_want_write_file(file);
218 if (ret)
219 return ret;
220
221 inode_lock(inode);
222 fsflags = btrfs_mask_fsflags_for_type(inode, fsflags);
223 old_fsflags = btrfs_inode_flags_to_fsflags(binode->flags);
224
225 ret = vfs_ioc_setflags_prepare(inode, old_fsflags, fsflags);
226 if (ret)
227 goto out_unlock;
228
229 ret = check_fsflags(old_fsflags, fsflags);
230 if (ret)
231 goto out_unlock;
232
233 binode_flags = binode->flags;
234 if (fsflags & FS_SYNC_FL)
235 binode_flags |= BTRFS_INODE_SYNC;
236 else
237 binode_flags &= ~BTRFS_INODE_SYNC;
238 if (fsflags & FS_IMMUTABLE_FL)
239 binode_flags |= BTRFS_INODE_IMMUTABLE;
240 else
241 binode_flags &= ~BTRFS_INODE_IMMUTABLE;
242 if (fsflags & FS_APPEND_FL)
243 binode_flags |= BTRFS_INODE_APPEND;
244 else
245 binode_flags &= ~BTRFS_INODE_APPEND;
246 if (fsflags & FS_NODUMP_FL)
247 binode_flags |= BTRFS_INODE_NODUMP;
248 else
249 binode_flags &= ~BTRFS_INODE_NODUMP;
250 if (fsflags & FS_NOATIME_FL)
251 binode_flags |= BTRFS_INODE_NOATIME;
252 else
253 binode_flags &= ~BTRFS_INODE_NOATIME;
254 if (fsflags & FS_DIRSYNC_FL)
255 binode_flags |= BTRFS_INODE_DIRSYNC;
256 else
257 binode_flags &= ~BTRFS_INODE_DIRSYNC;
258 if (fsflags & FS_NOCOW_FL) {
259 if (S_ISREG(inode->i_mode)) {
260 /*
261 * It's safe to turn csums off here, no extents exist.
262 * Otherwise we want the flag to reflect the real COW
263 * status of the file and will not set it.
264 */
265 if (inode->i_size == 0)
266 binode_flags |= BTRFS_INODE_NODATACOW |
267 BTRFS_INODE_NODATASUM;
268 } else {
269 binode_flags |= BTRFS_INODE_NODATACOW;
270 }
271 } else {
272 /*
273 * Revert back under same assumptions as above
274 */
275 if (S_ISREG(inode->i_mode)) {
276 if (inode->i_size == 0)
277 binode_flags &= ~(BTRFS_INODE_NODATACOW |
278 BTRFS_INODE_NODATASUM);
279 } else {
280 binode_flags &= ~BTRFS_INODE_NODATACOW;
281 }
282 }
283
284 /*
285 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
286 * flag may be changed automatically if compression code won't make
287 * things smaller.
288 */
289 if (fsflags & FS_NOCOMP_FL) {
290 binode_flags &= ~BTRFS_INODE_COMPRESS;
291 binode_flags |= BTRFS_INODE_NOCOMPRESS;
292 } else if (fsflags & FS_COMPR_FL) {
293
294 if (IS_SWAPFILE(inode)) {
295 ret = -ETXTBSY;
296 goto out_unlock;
297 }
298
299 binode_flags |= BTRFS_INODE_COMPRESS;
300 binode_flags &= ~BTRFS_INODE_NOCOMPRESS;
301
302 comp = btrfs_compress_type2str(fs_info->compress_type);
303 if (!comp || comp[0] == 0)
304 comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);
305 } else {
306 binode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
307 }
308
309 /*
310 * 1 for inode item
311 * 2 for properties
312 */
313 trans = btrfs_start_transaction(root, 3);
314 if (IS_ERR(trans)) {
315 ret = PTR_ERR(trans);
316 goto out_unlock;
317 }
318
319 if (comp) {
320 ret = btrfs_set_prop(trans, inode, "btrfs.compression", comp,
321 strlen(comp), 0);
322 if (ret) {
323 btrfs_abort_transaction(trans, ret);
324 goto out_end_trans;
325 }
326 } else {
327 ret = btrfs_set_prop(trans, inode, "btrfs.compression", NULL,
328 0, 0);
329 if (ret && ret != -ENODATA) {
330 btrfs_abort_transaction(trans, ret);
331 goto out_end_trans;
332 }
333 }
334
335 binode->flags = binode_flags;
336 btrfs_sync_inode_flags_to_i_flags(inode);
337 inode_inc_iversion(inode);
338 inode->i_ctime = current_time(inode);
339 ret = btrfs_update_inode(trans, root, inode);
340
341 out_end_trans:
342 btrfs_end_transaction(trans);
343 out_unlock:
344 inode_unlock(inode);
345 mnt_drop_write_file(file);
346 return ret;
347}
348
349/*
350 * Translate btrfs internal inode flags to xflags as expected by the
351 * FS_IOC_FSGETXATT ioctl. Filter only the supported ones, unknown flags are
352 * silently dropped.
353 */
354static unsigned int btrfs_inode_flags_to_xflags(unsigned int flags)
355{
356 unsigned int xflags = 0;
357
358 if (flags & BTRFS_INODE_APPEND)
359 xflags |= FS_XFLAG_APPEND;
360 if (flags & BTRFS_INODE_IMMUTABLE)
361 xflags |= FS_XFLAG_IMMUTABLE;
362 if (flags & BTRFS_INODE_NOATIME)
363 xflags |= FS_XFLAG_NOATIME;
364 if (flags & BTRFS_INODE_NODUMP)
365 xflags |= FS_XFLAG_NODUMP;
366 if (flags & BTRFS_INODE_SYNC)
367 xflags |= FS_XFLAG_SYNC;
368
369 return xflags;
370}
371
372/* Check if @flags are a supported and valid set of FS_XFLAGS_* flags */
373static int check_xflags(unsigned int flags)
374{
375 if (flags & ~(FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE | FS_XFLAG_NOATIME |
376 FS_XFLAG_NODUMP | FS_XFLAG_SYNC))
377 return -EOPNOTSUPP;
378 return 0;
379}
380
381/*
382 * Set the xflags from the internal inode flags. The remaining items of fsxattr
383 * are zeroed.
384 */
385static int btrfs_ioctl_fsgetxattr(struct file *file, void __user *arg)
386{
387 struct btrfs_inode *binode = BTRFS_I(file_inode(file));
388 struct fsxattr fa;
389
390 simple_fill_fsxattr(&fa, btrfs_inode_flags_to_xflags(binode->flags));
391 if (copy_to_user(arg, &fa, sizeof(fa)))
392 return -EFAULT;
393
394 return 0;
395}
396
397static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg)
398{
399 struct inode *inode = file_inode(file);
400 struct btrfs_inode *binode = BTRFS_I(inode);
401 struct btrfs_root *root = binode->root;
402 struct btrfs_trans_handle *trans;
403 struct fsxattr fa, old_fa;
404 unsigned old_flags;
405 unsigned old_i_flags;
406 int ret = 0;
407
408 if (!inode_owner_or_capable(inode))
409 return -EPERM;
410
411 if (btrfs_root_readonly(root))
412 return -EROFS;
413
414 if (copy_from_user(&fa, arg, sizeof(fa)))
415 return -EFAULT;
416
417 ret = check_xflags(fa.fsx_xflags);
418 if (ret)
419 return ret;
420
421 if (fa.fsx_extsize != 0 || fa.fsx_projid != 0 || fa.fsx_cowextsize != 0)
422 return -EOPNOTSUPP;
423
424 ret = mnt_want_write_file(file);
425 if (ret)
426 return ret;
427
428 inode_lock(inode);
429
430 old_flags = binode->flags;
431 old_i_flags = inode->i_flags;
432
433 simple_fill_fsxattr(&old_fa,
434 btrfs_inode_flags_to_xflags(binode->flags));
435 ret = vfs_ioc_fssetxattr_check(inode, &old_fa, &fa);
436 if (ret)
437 goto out_unlock;
438
439 if (fa.fsx_xflags & FS_XFLAG_SYNC)
440 binode->flags |= BTRFS_INODE_SYNC;
441 else
442 binode->flags &= ~BTRFS_INODE_SYNC;
443 if (fa.fsx_xflags & FS_XFLAG_IMMUTABLE)
444 binode->flags |= BTRFS_INODE_IMMUTABLE;
445 else
446 binode->flags &= ~BTRFS_INODE_IMMUTABLE;
447 if (fa.fsx_xflags & FS_XFLAG_APPEND)
448 binode->flags |= BTRFS_INODE_APPEND;
449 else
450 binode->flags &= ~BTRFS_INODE_APPEND;
451 if (fa.fsx_xflags & FS_XFLAG_NODUMP)
452 binode->flags |= BTRFS_INODE_NODUMP;
453 else
454 binode->flags &= ~BTRFS_INODE_NODUMP;
455 if (fa.fsx_xflags & FS_XFLAG_NOATIME)
456 binode->flags |= BTRFS_INODE_NOATIME;
457 else
458 binode->flags &= ~BTRFS_INODE_NOATIME;
459
460 /* 1 item for the inode */
461 trans = btrfs_start_transaction(root, 1);
462 if (IS_ERR(trans)) {
463 ret = PTR_ERR(trans);
464 goto out_unlock;
465 }
466
467 btrfs_sync_inode_flags_to_i_flags(inode);
468 inode_inc_iversion(inode);
469 inode->i_ctime = current_time(inode);
470 ret = btrfs_update_inode(trans, root, inode);
471
472 btrfs_end_transaction(trans);
473
474out_unlock:
475 if (ret) {
476 binode->flags = old_flags;
477 inode->i_flags = old_i_flags;
478 }
479
480 inode_unlock(inode);
481 mnt_drop_write_file(file);
482
483 return ret;
484}
485
486static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
487{
488 struct inode *inode = file_inode(file);
489
490 return put_user(inode->i_generation, arg);
491}
492
493static noinline int btrfs_ioctl_fitrim(struct btrfs_fs_info *fs_info,
494 void __user *arg)
495{
496 struct btrfs_device *device;
497 struct request_queue *q;
498 struct fstrim_range range;
499 u64 minlen = ULLONG_MAX;
500 u64 num_devices = 0;
501 int ret;
502
503 if (!capable(CAP_SYS_ADMIN))
504 return -EPERM;
505
506 /*
507 * If the fs is mounted with nologreplay, which requires it to be
508 * mounted in RO mode as well, we can not allow discard on free space
509 * inside block groups, because log trees refer to extents that are not
510 * pinned in a block group's free space cache (pinning the extents is
511 * precisely the first phase of replaying a log tree).
512 */
513 if (btrfs_test_opt(fs_info, NOLOGREPLAY))
514 return -EROFS;
515
516 rcu_read_lock();
517 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
518 dev_list) {
519 if (!device->bdev)
520 continue;
521 q = bdev_get_queue(device->bdev);
522 if (blk_queue_discard(q)) {
523 num_devices++;
524 minlen = min_t(u64, q->limits.discard_granularity,
525 minlen);
526 }
527 }
528 rcu_read_unlock();
529
530 if (!num_devices)
531 return -EOPNOTSUPP;
532 if (copy_from_user(&range, arg, sizeof(range)))
533 return -EFAULT;
534
535 /*
536 * NOTE: Don't truncate the range using super->total_bytes. Bytenr of
537 * block group is in the logical address space, which can be any
538 * sectorsize aligned bytenr in the range [0, U64_MAX].
539 */
540 if (range.len < fs_info->sb->s_blocksize)
541 return -EINVAL;
542
543 range.minlen = max(range.minlen, minlen);
544 ret = btrfs_trim_fs(fs_info, &range);
545 if (ret < 0)
546 return ret;
547
548 if (copy_to_user(arg, &range, sizeof(range)))
549 return -EFAULT;
550
551 return 0;
552}
553
554int __pure btrfs_is_empty_uuid(u8 *uuid)
555{
556 int i;
557
558 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
559 if (uuid[i])
560 return 0;
561 }
562 return 1;
563}
564
565static noinline int create_subvol(struct inode *dir,
566 struct dentry *dentry,
567 const char *name, int namelen,
568 struct btrfs_qgroup_inherit *inherit)
569{
570 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
571 struct btrfs_trans_handle *trans;
572 struct btrfs_key key;
573 struct btrfs_root_item *root_item;
574 struct btrfs_inode_item *inode_item;
575 struct extent_buffer *leaf;
576 struct btrfs_root *root = BTRFS_I(dir)->root;
577 struct btrfs_root *new_root;
578 struct btrfs_block_rsv block_rsv;
579 struct timespec64 cur_time = current_time(dir);
580 struct inode *inode;
581 int ret;
582 int err;
583 dev_t anon_dev = 0;
584 u64 objectid;
585 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
586 u64 index = 0;
587
588 root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
589 if (!root_item)
590 return -ENOMEM;
591
592 ret = btrfs_find_free_objectid(fs_info->tree_root, &objectid);
593 if (ret)
594 goto fail_free;
595
596 ret = get_anon_bdev(&anon_dev);
597 if (ret < 0)
598 goto fail_free;
599
600 /*
601 * Don't create subvolume whose level is not zero. Or qgroup will be
602 * screwed up since it assumes subvolume qgroup's level to be 0.
603 */
604 if (btrfs_qgroup_level(objectid)) {
605 ret = -ENOSPC;
606 goto fail_free;
607 }
608
609 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
610 /*
611 * The same as the snapshot creation, please see the comment
612 * of create_snapshot().
613 */
614 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 8, false);
615 if (ret)
616 goto fail_free;
617
618 trans = btrfs_start_transaction(root, 0);
619 if (IS_ERR(trans)) {
620 ret = PTR_ERR(trans);
621 btrfs_subvolume_release_metadata(fs_info, &block_rsv);
622 goto fail_free;
623 }
624 trans->block_rsv = &block_rsv;
625 trans->bytes_reserved = block_rsv.size;
626
627 ret = btrfs_qgroup_inherit(trans, 0, objectid, inherit);
628 if (ret)
629 goto fail;
630
631 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
632 if (IS_ERR(leaf)) {
633 ret = PTR_ERR(leaf);
634 goto fail;
635 }
636
637 btrfs_mark_buffer_dirty(leaf);
638
639 inode_item = &root_item->inode;
640 btrfs_set_stack_inode_generation(inode_item, 1);
641 btrfs_set_stack_inode_size(inode_item, 3);
642 btrfs_set_stack_inode_nlink(inode_item, 1);
643 btrfs_set_stack_inode_nbytes(inode_item,
644 fs_info->nodesize);
645 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
646
647 btrfs_set_root_flags(root_item, 0);
648 btrfs_set_root_limit(root_item, 0);
649 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
650
651 btrfs_set_root_bytenr(root_item, leaf->start);
652 btrfs_set_root_generation(root_item, trans->transid);
653 btrfs_set_root_level(root_item, 0);
654 btrfs_set_root_refs(root_item, 1);
655 btrfs_set_root_used(root_item, leaf->len);
656 btrfs_set_root_last_snapshot(root_item, 0);
657
658 btrfs_set_root_generation_v2(root_item,
659 btrfs_root_generation(root_item));
660 generate_random_guid(root_item->uuid);
661 btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);
662 btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);
663 root_item->ctime = root_item->otime;
664 btrfs_set_root_ctransid(root_item, trans->transid);
665 btrfs_set_root_otransid(root_item, trans->transid);
666
667 btrfs_tree_unlock(leaf);
668 free_extent_buffer(leaf);
669 leaf = NULL;
670
671 btrfs_set_root_dirid(root_item, new_dirid);
672
673 key.objectid = objectid;
674 key.offset = 0;
675 key.type = BTRFS_ROOT_ITEM_KEY;
676 ret = btrfs_insert_root(trans, fs_info->tree_root, &key,
677 root_item);
678 if (ret)
679 goto fail;
680
681 key.offset = (u64)-1;
682 new_root = btrfs_get_new_fs_root(fs_info, objectid, anon_dev);
683 if (IS_ERR(new_root)) {
684 free_anon_bdev(anon_dev);
685 ret = PTR_ERR(new_root);
686 btrfs_abort_transaction(trans, ret);
687 goto fail;
688 }
689 /* Freeing will be done in btrfs_put_root() of new_root */
690 anon_dev = 0;
691
692 btrfs_record_root_in_trans(trans, new_root);
693
694 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
695 btrfs_put_root(new_root);
696 if (ret) {
697 /* We potentially lose an unused inode item here */
698 btrfs_abort_transaction(trans, ret);
699 goto fail;
700 }
701
702 mutex_lock(&new_root->objectid_mutex);
703 new_root->highest_objectid = new_dirid;
704 mutex_unlock(&new_root->objectid_mutex);
705
706 /*
707 * insert the directory item
708 */
709 ret = btrfs_set_inode_index(BTRFS_I(dir), &index);
710 if (ret) {
711 btrfs_abort_transaction(trans, ret);
712 goto fail;
713 }
714
715 ret = btrfs_insert_dir_item(trans, name, namelen, BTRFS_I(dir), &key,
716 BTRFS_FT_DIR, index);
717 if (ret) {
718 btrfs_abort_transaction(trans, ret);
719 goto fail;
720 }
721
722 btrfs_i_size_write(BTRFS_I(dir), dir->i_size + namelen * 2);
723 ret = btrfs_update_inode(trans, root, dir);
724 if (ret) {
725 btrfs_abort_transaction(trans, ret);
726 goto fail;
727 }
728
729 ret = btrfs_add_root_ref(trans, objectid, root->root_key.objectid,
730 btrfs_ino(BTRFS_I(dir)), index, name, namelen);
731 if (ret) {
732 btrfs_abort_transaction(trans, ret);
733 goto fail;
734 }
735
736 ret = btrfs_uuid_tree_add(trans, root_item->uuid,
737 BTRFS_UUID_KEY_SUBVOL, objectid);
738 if (ret)
739 btrfs_abort_transaction(trans, ret);
740
741fail:
742 kfree(root_item);
743 trans->block_rsv = NULL;
744 trans->bytes_reserved = 0;
745 btrfs_subvolume_release_metadata(fs_info, &block_rsv);
746
747 err = btrfs_commit_transaction(trans);
748 if (err && !ret)
749 ret = err;
750
751 if (!ret) {
752 inode = btrfs_lookup_dentry(dir, dentry);
753 if (IS_ERR(inode))
754 return PTR_ERR(inode);
755 d_instantiate(dentry, inode);
756 }
757 return ret;
758
759fail_free:
760 if (anon_dev)
761 free_anon_bdev(anon_dev);
762 kfree(root_item);
763 return ret;
764}
765
766static int create_snapshot(struct btrfs_root *root, struct inode *dir,
767 struct dentry *dentry, bool readonly,
768 struct btrfs_qgroup_inherit *inherit)
769{
770 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
771 struct inode *inode;
772 struct btrfs_pending_snapshot *pending_snapshot;
773 struct btrfs_trans_handle *trans;
774 int ret;
775
776 if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
777 return -EINVAL;
778
779 if (atomic_read(&root->nr_swapfiles)) {
780 btrfs_warn(fs_info,
781 "cannot snapshot subvolume with active swapfile");
782 return -ETXTBSY;
783 }
784
785 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL);
786 if (!pending_snapshot)
787 return -ENOMEM;
788
789 ret = get_anon_bdev(&pending_snapshot->anon_dev);
790 if (ret < 0)
791 goto free_pending;
792 pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
793 GFP_KERNEL);
794 pending_snapshot->path = btrfs_alloc_path();
795 if (!pending_snapshot->root_item || !pending_snapshot->path) {
796 ret = -ENOMEM;
797 goto free_pending;
798 }
799
800 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
801 BTRFS_BLOCK_RSV_TEMP);
802 /*
803 * 1 - parent dir inode
804 * 2 - dir entries
805 * 1 - root item
806 * 2 - root ref/backref
807 * 1 - root of snapshot
808 * 1 - UUID item
809 */
810 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
811 &pending_snapshot->block_rsv, 8,
812 false);
813 if (ret)
814 goto free_pending;
815
816 pending_snapshot->dentry = dentry;
817 pending_snapshot->root = root;
818 pending_snapshot->readonly = readonly;
819 pending_snapshot->dir = dir;
820 pending_snapshot->inherit = inherit;
821
822 trans = btrfs_start_transaction(root, 0);
823 if (IS_ERR(trans)) {
824 ret = PTR_ERR(trans);
825 goto fail;
826 }
827
828 spin_lock(&fs_info->trans_lock);
829 list_add(&pending_snapshot->list,
830 &trans->transaction->pending_snapshots);
831 spin_unlock(&fs_info->trans_lock);
832
833 ret = btrfs_commit_transaction(trans);
834 if (ret)
835 goto fail;
836
837 ret = pending_snapshot->error;
838 if (ret)
839 goto fail;
840
841 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
842 if (ret)
843 goto fail;
844
845 inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
846 if (IS_ERR(inode)) {
847 ret = PTR_ERR(inode);
848 goto fail;
849 }
850
851 d_instantiate(dentry, inode);
852 ret = 0;
853 pending_snapshot->anon_dev = 0;
854fail:
855 /* Prevent double freeing of anon_dev */
856 if (ret && pending_snapshot->snap)
857 pending_snapshot->snap->anon_dev = 0;
858 btrfs_put_root(pending_snapshot->snap);
859 btrfs_subvolume_release_metadata(fs_info, &pending_snapshot->block_rsv);
860free_pending:
861 if (pending_snapshot->anon_dev)
862 free_anon_bdev(pending_snapshot->anon_dev);
863 kfree(pending_snapshot->root_item);
864 btrfs_free_path(pending_snapshot->path);
865 kfree(pending_snapshot);
866
867 return ret;
868}
869
870/* copy of may_delete in fs/namei.c()
871 * Check whether we can remove a link victim from directory dir, check
872 * whether the type of victim is right.
873 * 1. We can't do it if dir is read-only (done in permission())
874 * 2. We should have write and exec permissions on dir
875 * 3. We can't remove anything from append-only dir
876 * 4. We can't do anything with immutable dir (done in permission())
877 * 5. If the sticky bit on dir is set we should either
878 * a. be owner of dir, or
879 * b. be owner of victim, or
880 * c. have CAP_FOWNER capability
881 * 6. If the victim is append-only or immutable we can't do anything with
882 * links pointing to it.
883 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
884 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
885 * 9. We can't remove a root or mountpoint.
886 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
887 * nfs_async_unlink().
888 */
889
890static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
891{
892 int error;
893
894 if (d_really_is_negative(victim))
895 return -ENOENT;
896
897 BUG_ON(d_inode(victim->d_parent) != dir);
898 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
899
900 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
901 if (error)
902 return error;
903 if (IS_APPEND(dir))
904 return -EPERM;
905 if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
906 IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
907 return -EPERM;
908 if (isdir) {
909 if (!d_is_dir(victim))
910 return -ENOTDIR;
911 if (IS_ROOT(victim))
912 return -EBUSY;
913 } else if (d_is_dir(victim))
914 return -EISDIR;
915 if (IS_DEADDIR(dir))
916 return -ENOENT;
917 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
918 return -EBUSY;
919 return 0;
920}
921
922/* copy of may_create in fs/namei.c() */
923static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
924{
925 if (d_really_is_positive(child))
926 return -EEXIST;
927 if (IS_DEADDIR(dir))
928 return -ENOENT;
929 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
930}
931
932/*
933 * Create a new subvolume below @parent. This is largely modeled after
934 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
935 * inside this filesystem so it's quite a bit simpler.
936 */
937static noinline int btrfs_mksubvol(const struct path *parent,
938 const char *name, int namelen,
939 struct btrfs_root *snap_src,
940 bool readonly,
941 struct btrfs_qgroup_inherit *inherit)
942{
943 struct inode *dir = d_inode(parent->dentry);
944 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
945 struct dentry *dentry;
946 int error;
947
948 error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
949 if (error == -EINTR)
950 return error;
951
952 dentry = lookup_one_len(name, parent->dentry, namelen);
953 error = PTR_ERR(dentry);
954 if (IS_ERR(dentry))
955 goto out_unlock;
956
957 error = btrfs_may_create(dir, dentry);
958 if (error)
959 goto out_dput;
960
961 /*
962 * even if this name doesn't exist, we may get hash collisions.
963 * check for them now when we can safely fail
964 */
965 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
966 dir->i_ino, name,
967 namelen);
968 if (error)
969 goto out_dput;
970
971 down_read(&fs_info->subvol_sem);
972
973 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
974 goto out_up_read;
975
976 if (snap_src)
977 error = create_snapshot(snap_src, dir, dentry, readonly, inherit);
978 else
979 error = create_subvol(dir, dentry, name, namelen, inherit);
980
981 if (!error)
982 fsnotify_mkdir(dir, dentry);
983out_up_read:
984 up_read(&fs_info->subvol_sem);
985out_dput:
986 dput(dentry);
987out_unlock:
988 inode_unlock(dir);
989 return error;
990}
991
992static noinline int btrfs_mksnapshot(const struct path *parent,
993 const char *name, int namelen,
994 struct btrfs_root *root,
995 bool readonly,
996 struct btrfs_qgroup_inherit *inherit)
997{
998 int ret;
999 bool snapshot_force_cow = false;
1000
1001 /*
1002 * Force new buffered writes to reserve space even when NOCOW is
1003 * possible. This is to avoid later writeback (running dealloc) to
1004 * fallback to COW mode and unexpectedly fail with ENOSPC.
1005 */
1006 btrfs_drew_read_lock(&root->snapshot_lock);
1007
1008 ret = btrfs_start_delalloc_snapshot(root);
1009 if (ret)
1010 goto out;
1011
1012 /*
1013 * All previous writes have started writeback in NOCOW mode, so now
1014 * we force future writes to fallback to COW mode during snapshot
1015 * creation.
1016 */
1017 atomic_inc(&root->snapshot_force_cow);
1018 snapshot_force_cow = true;
1019
1020 btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
1021
1022 ret = btrfs_mksubvol(parent, name, namelen,
1023 root, readonly, inherit);
1024out:
1025 if (snapshot_force_cow)
1026 atomic_dec(&root->snapshot_force_cow);
1027 btrfs_drew_read_unlock(&root->snapshot_lock);
1028 return ret;
1029}
1030
1031/*
1032 * When we're defragging a range, we don't want to kick it off again
1033 * if it is really just waiting for delalloc to send it down.
1034 * If we find a nice big extent or delalloc range for the bytes in the
1035 * file you want to defrag, we return 0 to let you know to skip this
1036 * part of the file
1037 */
1038static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
1039{
1040 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1041 struct extent_map *em = NULL;
1042 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1043 u64 end;
1044
1045 read_lock(&em_tree->lock);
1046 em = lookup_extent_mapping(em_tree, offset, PAGE_SIZE);
1047 read_unlock(&em_tree->lock);
1048
1049 if (em) {
1050 end = extent_map_end(em);
1051 free_extent_map(em);
1052 if (end - offset > thresh)
1053 return 0;
1054 }
1055 /* if we already have a nice delalloc here, just stop */
1056 thresh /= 2;
1057 end = count_range_bits(io_tree, &offset, offset + thresh,
1058 thresh, EXTENT_DELALLOC, 1);
1059 if (end >= thresh)
1060 return 0;
1061 return 1;
1062}
1063
1064/*
1065 * helper function to walk through a file and find extents
1066 * newer than a specific transid, and smaller than thresh.
1067 *
1068 * This is used by the defragging code to find new and small
1069 * extents
1070 */
1071static int find_new_extents(struct btrfs_root *root,
1072 struct inode *inode, u64 newer_than,
1073 u64 *off, u32 thresh)
1074{
1075 struct btrfs_path *path;
1076 struct btrfs_key min_key;
1077 struct extent_buffer *leaf;
1078 struct btrfs_file_extent_item *extent;
1079 int type;
1080 int ret;
1081 u64 ino = btrfs_ino(BTRFS_I(inode));
1082
1083 path = btrfs_alloc_path();
1084 if (!path)
1085 return -ENOMEM;
1086
1087 min_key.objectid = ino;
1088 min_key.type = BTRFS_EXTENT_DATA_KEY;
1089 min_key.offset = *off;
1090
1091 while (1) {
1092 ret = btrfs_search_forward(root, &min_key, path, newer_than);
1093 if (ret != 0)
1094 goto none;
1095process_slot:
1096 if (min_key.objectid != ino)
1097 goto none;
1098 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
1099 goto none;
1100
1101 leaf = path->nodes[0];
1102 extent = btrfs_item_ptr(leaf, path->slots[0],
1103 struct btrfs_file_extent_item);
1104
1105 type = btrfs_file_extent_type(leaf, extent);
1106 if (type == BTRFS_FILE_EXTENT_REG &&
1107 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
1108 check_defrag_in_cache(inode, min_key.offset, thresh)) {
1109 *off = min_key.offset;
1110 btrfs_free_path(path);
1111 return 0;
1112 }
1113
1114 path->slots[0]++;
1115 if (path->slots[0] < btrfs_header_nritems(leaf)) {
1116 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
1117 goto process_slot;
1118 }
1119
1120 if (min_key.offset == (u64)-1)
1121 goto none;
1122
1123 min_key.offset++;
1124 btrfs_release_path(path);
1125 }
1126none:
1127 btrfs_free_path(path);
1128 return -ENOENT;
1129}
1130
1131static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
1132{
1133 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1134 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1135 struct extent_map *em;
1136 u64 len = PAGE_SIZE;
1137
1138 /*
1139 * hopefully we have this extent in the tree already, try without
1140 * the full extent lock
1141 */
1142 read_lock(&em_tree->lock);
1143 em = lookup_extent_mapping(em_tree, start, len);
1144 read_unlock(&em_tree->lock);
1145
1146 if (!em) {
1147 struct extent_state *cached = NULL;
1148 u64 end = start + len - 1;
1149
1150 /* get the big lock and read metadata off disk */
1151 lock_extent_bits(io_tree, start, end, &cached);
1152 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len);
1153 unlock_extent_cached(io_tree, start, end, &cached);
1154
1155 if (IS_ERR(em))
1156 return NULL;
1157 }
1158
1159 return em;
1160}
1161
1162static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1163{
1164 struct extent_map *next;
1165 bool ret = true;
1166
1167 /* this is the last extent */
1168 if (em->start + em->len >= i_size_read(inode))
1169 return false;
1170
1171 next = defrag_lookup_extent(inode, em->start + em->len);
1172 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1173 ret = false;
1174 else if ((em->block_start + em->block_len == next->block_start) &&
1175 (em->block_len > SZ_128K && next->block_len > SZ_128K))
1176 ret = false;
1177
1178 free_extent_map(next);
1179 return ret;
1180}
1181
1182static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1183 u64 *last_len, u64 *skip, u64 *defrag_end,
1184 int compress)
1185{
1186 struct extent_map *em;
1187 int ret = 1;
1188 bool next_mergeable = true;
1189 bool prev_mergeable = true;
1190
1191 /*
1192 * make sure that once we start defragging an extent, we keep on
1193 * defragging it
1194 */
1195 if (start < *defrag_end)
1196 return 1;
1197
1198 *skip = 0;
1199
1200 em = defrag_lookup_extent(inode, start);
1201 if (!em)
1202 return 0;
1203
1204 /* this will cover holes, and inline extents */
1205 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1206 ret = 0;
1207 goto out;
1208 }
1209
1210 if (!*defrag_end)
1211 prev_mergeable = false;
1212
1213 next_mergeable = defrag_check_next_extent(inode, em);
1214 /*
1215 * we hit a real extent, if it is big or the next extent is not a
1216 * real extent, don't bother defragging it
1217 */
1218 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1219 (em->len >= thresh || (!next_mergeable && !prev_mergeable)))
1220 ret = 0;
1221out:
1222 /*
1223 * last_len ends up being a counter of how many bytes we've defragged.
1224 * every time we choose not to defrag an extent, we reset *last_len
1225 * so that the next tiny extent will force a defrag.
1226 *
1227 * The end result of this is that tiny extents before a single big
1228 * extent will force at least part of that big extent to be defragged.
1229 */
1230 if (ret) {
1231 *defrag_end = extent_map_end(em);
1232 } else {
1233 *last_len = 0;
1234 *skip = extent_map_end(em);
1235 *defrag_end = 0;
1236 }
1237
1238 free_extent_map(em);
1239 return ret;
1240}
1241
1242/*
1243 * it doesn't do much good to defrag one or two pages
1244 * at a time. This pulls in a nice chunk of pages
1245 * to COW and defrag.
1246 *
1247 * It also makes sure the delalloc code has enough
1248 * dirty data to avoid making new small extents as part
1249 * of the defrag
1250 *
1251 * It's a good idea to start RA on this range
1252 * before calling this.
1253 */
1254static int cluster_pages_for_defrag(struct inode *inode,
1255 struct page **pages,
1256 unsigned long start_index,
1257 unsigned long num_pages)
1258{
1259 unsigned long file_end;
1260 u64 isize = i_size_read(inode);
1261 u64 page_start;
1262 u64 page_end;
1263 u64 page_cnt;
1264 int ret;
1265 int i;
1266 int i_done;
1267 struct btrfs_ordered_extent *ordered;
1268 struct extent_state *cached_state = NULL;
1269 struct extent_io_tree *tree;
1270 struct extent_changeset *data_reserved = NULL;
1271 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1272
1273 file_end = (isize - 1) >> PAGE_SHIFT;
1274 if (!isize || start_index > file_end)
1275 return 0;
1276
1277 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1278
1279 ret = btrfs_delalloc_reserve_space(BTRFS_I(inode), &data_reserved,
1280 start_index << PAGE_SHIFT,
1281 page_cnt << PAGE_SHIFT);
1282 if (ret)
1283 return ret;
1284 i_done = 0;
1285 tree = &BTRFS_I(inode)->io_tree;
1286
1287 /* step one, lock all the pages */
1288 for (i = 0; i < page_cnt; i++) {
1289 struct page *page;
1290again:
1291 page = find_or_create_page(inode->i_mapping,
1292 start_index + i, mask);
1293 if (!page)
1294 break;
1295
1296 page_start = page_offset(page);
1297 page_end = page_start + PAGE_SIZE - 1;
1298 while (1) {
1299 lock_extent_bits(tree, page_start, page_end,
1300 &cached_state);
1301 ordered = btrfs_lookup_ordered_extent(BTRFS_I(inode),
1302 page_start);
1303 unlock_extent_cached(tree, page_start, page_end,
1304 &cached_state);
1305 if (!ordered)
1306 break;
1307
1308 unlock_page(page);
1309 btrfs_start_ordered_extent(inode, ordered, 1);
1310 btrfs_put_ordered_extent(ordered);
1311 lock_page(page);
1312 /*
1313 * we unlocked the page above, so we need check if
1314 * it was released or not.
1315 */
1316 if (page->mapping != inode->i_mapping) {
1317 unlock_page(page);
1318 put_page(page);
1319 goto again;
1320 }
1321 }
1322
1323 if (!PageUptodate(page)) {
1324 btrfs_readpage(NULL, page);
1325 lock_page(page);
1326 if (!PageUptodate(page)) {
1327 unlock_page(page);
1328 put_page(page);
1329 ret = -EIO;
1330 break;
1331 }
1332 }
1333
1334 if (page->mapping != inode->i_mapping) {
1335 unlock_page(page);
1336 put_page(page);
1337 goto again;
1338 }
1339
1340 pages[i] = page;
1341 i_done++;
1342 }
1343 if (!i_done || ret)
1344 goto out;
1345
1346 if (!(inode->i_sb->s_flags & SB_ACTIVE))
1347 goto out;
1348
1349 /*
1350 * so now we have a nice long stream of locked
1351 * and up to date pages, lets wait on them
1352 */
1353 for (i = 0; i < i_done; i++)
1354 wait_on_page_writeback(pages[i]);
1355
1356 page_start = page_offset(pages[0]);
1357 page_end = page_offset(pages[i_done - 1]) + PAGE_SIZE;
1358
1359 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1360 page_start, page_end - 1, &cached_state);
1361 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1362 page_end - 1, EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |
1363 EXTENT_DEFRAG, 0, 0, &cached_state);
1364
1365 if (i_done != page_cnt) {
1366 spin_lock(&BTRFS_I(inode)->lock);
1367 btrfs_mod_outstanding_extents(BTRFS_I(inode), 1);
1368 spin_unlock(&BTRFS_I(inode)->lock);
1369 btrfs_delalloc_release_space(BTRFS_I(inode), data_reserved,
1370 start_index << PAGE_SHIFT,
1371 (page_cnt - i_done) << PAGE_SHIFT, true);
1372 }
1373
1374
1375 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1376 &cached_state);
1377
1378 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1379 page_start, page_end - 1, &cached_state);
1380
1381 for (i = 0; i < i_done; i++) {
1382 clear_page_dirty_for_io(pages[i]);
1383 ClearPageChecked(pages[i]);
1384 set_page_extent_mapped(pages[i]);
1385 set_page_dirty(pages[i]);
1386 unlock_page(pages[i]);
1387 put_page(pages[i]);
1388 }
1389 btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT);
1390 extent_changeset_free(data_reserved);
1391 return i_done;
1392out:
1393 for (i = 0; i < i_done; i++) {
1394 unlock_page(pages[i]);
1395 put_page(pages[i]);
1396 }
1397 btrfs_delalloc_release_space(BTRFS_I(inode), data_reserved,
1398 start_index << PAGE_SHIFT,
1399 page_cnt << PAGE_SHIFT, true);
1400 btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT);
1401 extent_changeset_free(data_reserved);
1402 return ret;
1403
1404}
1405
1406int btrfs_defrag_file(struct inode *inode, struct file *file,
1407 struct btrfs_ioctl_defrag_range_args *range,
1408 u64 newer_than, unsigned long max_to_defrag)
1409{
1410 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1411 struct btrfs_root *root = BTRFS_I(inode)->root;
1412 struct file_ra_state *ra = NULL;
1413 unsigned long last_index;
1414 u64 isize = i_size_read(inode);
1415 u64 last_len = 0;
1416 u64 skip = 0;
1417 u64 defrag_end = 0;
1418 u64 newer_off = range->start;
1419 unsigned long i;
1420 unsigned long ra_index = 0;
1421 int ret;
1422 int defrag_count = 0;
1423 int compress_type = BTRFS_COMPRESS_ZLIB;
1424 u32 extent_thresh = range->extent_thresh;
1425 unsigned long max_cluster = SZ_256K >> PAGE_SHIFT;
1426 unsigned long cluster = max_cluster;
1427 u64 new_align = ~((u64)SZ_128K - 1);
1428 struct page **pages = NULL;
1429 bool do_compress = range->flags & BTRFS_DEFRAG_RANGE_COMPRESS;
1430
1431 if (isize == 0)
1432 return 0;
1433
1434 if (range->start >= isize)
1435 return -EINVAL;
1436
1437 if (do_compress) {
1438 if (range->compress_type >= BTRFS_NR_COMPRESS_TYPES)
1439 return -EINVAL;
1440 if (range->compress_type)
1441 compress_type = range->compress_type;
1442 }
1443
1444 if (extent_thresh == 0)
1445 extent_thresh = SZ_256K;
1446
1447 /*
1448 * If we were not given a file, allocate a readahead context. As
1449 * readahead is just an optimization, defrag will work without it so
1450 * we don't error out.
1451 */
1452 if (!file) {
1453 ra = kzalloc(sizeof(*ra), GFP_KERNEL);
1454 if (ra)
1455 file_ra_state_init(ra, inode->i_mapping);
1456 } else {
1457 ra = &file->f_ra;
1458 }
1459
1460 pages = kmalloc_array(max_cluster, sizeof(struct page *), GFP_KERNEL);
1461 if (!pages) {
1462 ret = -ENOMEM;
1463 goto out_ra;
1464 }
1465
1466 /* find the last page to defrag */
1467 if (range->start + range->len > range->start) {
1468 last_index = min_t(u64, isize - 1,
1469 range->start + range->len - 1) >> PAGE_SHIFT;
1470 } else {
1471 last_index = (isize - 1) >> PAGE_SHIFT;
1472 }
1473
1474 if (newer_than) {
1475 ret = find_new_extents(root, inode, newer_than,
1476 &newer_off, SZ_64K);
1477 if (!ret) {
1478 range->start = newer_off;
1479 /*
1480 * we always align our defrag to help keep
1481 * the extents in the file evenly spaced
1482 */
1483 i = (newer_off & new_align) >> PAGE_SHIFT;
1484 } else
1485 goto out_ra;
1486 } else {
1487 i = range->start >> PAGE_SHIFT;
1488 }
1489 if (!max_to_defrag)
1490 max_to_defrag = last_index - i + 1;
1491
1492 /*
1493 * make writeback starts from i, so the defrag range can be
1494 * written sequentially.
1495 */
1496 if (i < inode->i_mapping->writeback_index)
1497 inode->i_mapping->writeback_index = i;
1498
1499 while (i <= last_index && defrag_count < max_to_defrag &&
1500 (i < DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE))) {
1501 /*
1502 * make sure we stop running if someone unmounts
1503 * the FS
1504 */
1505 if (!(inode->i_sb->s_flags & SB_ACTIVE))
1506 break;
1507
1508 if (btrfs_defrag_cancelled(fs_info)) {
1509 btrfs_debug(fs_info, "defrag_file cancelled");
1510 ret = -EAGAIN;
1511 break;
1512 }
1513
1514 if (!should_defrag_range(inode, (u64)i << PAGE_SHIFT,
1515 extent_thresh, &last_len, &skip,
1516 &defrag_end, do_compress)){
1517 unsigned long next;
1518 /*
1519 * the should_defrag function tells us how much to skip
1520 * bump our counter by the suggested amount
1521 */
1522 next = DIV_ROUND_UP(skip, PAGE_SIZE);
1523 i = max(i + 1, next);
1524 continue;
1525 }
1526
1527 if (!newer_than) {
1528 cluster = (PAGE_ALIGN(defrag_end) >>
1529 PAGE_SHIFT) - i;
1530 cluster = min(cluster, max_cluster);
1531 } else {
1532 cluster = max_cluster;
1533 }
1534
1535 if (i + cluster > ra_index) {
1536 ra_index = max(i, ra_index);
1537 if (ra)
1538 page_cache_sync_readahead(inode->i_mapping, ra,
1539 file, ra_index, cluster);
1540 ra_index += cluster;
1541 }
1542
1543 inode_lock(inode);
1544 if (IS_SWAPFILE(inode)) {
1545 ret = -ETXTBSY;
1546 } else {
1547 if (do_compress)
1548 BTRFS_I(inode)->defrag_compress = compress_type;
1549 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1550 }
1551 if (ret < 0) {
1552 inode_unlock(inode);
1553 goto out_ra;
1554 }
1555
1556 defrag_count += ret;
1557 balance_dirty_pages_ratelimited(inode->i_mapping);
1558 inode_unlock(inode);
1559
1560 if (newer_than) {
1561 if (newer_off == (u64)-1)
1562 break;
1563
1564 if (ret > 0)
1565 i += ret;
1566
1567 newer_off = max(newer_off + 1,
1568 (u64)i << PAGE_SHIFT);
1569
1570 ret = find_new_extents(root, inode, newer_than,
1571 &newer_off, SZ_64K);
1572 if (!ret) {
1573 range->start = newer_off;
1574 i = (newer_off & new_align) >> PAGE_SHIFT;
1575 } else {
1576 break;
1577 }
1578 } else {
1579 if (ret > 0) {
1580 i += ret;
1581 last_len += ret << PAGE_SHIFT;
1582 } else {
1583 i++;
1584 last_len = 0;
1585 }
1586 }
1587 }
1588
1589 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1590 filemap_flush(inode->i_mapping);
1591 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1592 &BTRFS_I(inode)->runtime_flags))
1593 filemap_flush(inode->i_mapping);
1594 }
1595
1596 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1597 btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
1598 } else if (range->compress_type == BTRFS_COMPRESS_ZSTD) {
1599 btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
1600 }
1601
1602 ret = defrag_count;
1603
1604out_ra:
1605 if (do_compress) {
1606 inode_lock(inode);
1607 BTRFS_I(inode)->defrag_compress = BTRFS_COMPRESS_NONE;
1608 inode_unlock(inode);
1609 }
1610 if (!file)
1611 kfree(ra);
1612 kfree(pages);
1613 return ret;
1614}
1615
1616static noinline int btrfs_ioctl_resize(struct file *file,
1617 void __user *arg)
1618{
1619 struct inode *inode = file_inode(file);
1620 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1621 u64 new_size;
1622 u64 old_size;
1623 u64 devid = 1;
1624 struct btrfs_root *root = BTRFS_I(inode)->root;
1625 struct btrfs_ioctl_vol_args *vol_args;
1626 struct btrfs_trans_handle *trans;
1627 struct btrfs_device *device = NULL;
1628 char *sizestr;
1629 char *retptr;
1630 char *devstr = NULL;
1631 int ret = 0;
1632 int mod = 0;
1633
1634 if (!capable(CAP_SYS_ADMIN))
1635 return -EPERM;
1636
1637 ret = mnt_want_write_file(file);
1638 if (ret)
1639 return ret;
1640
1641 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
1642 mnt_drop_write_file(file);
1643 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1644 }
1645
1646 vol_args = memdup_user(arg, sizeof(*vol_args));
1647 if (IS_ERR(vol_args)) {
1648 ret = PTR_ERR(vol_args);
1649 goto out;
1650 }
1651
1652 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1653
1654 sizestr = vol_args->name;
1655 devstr = strchr(sizestr, ':');
1656 if (devstr) {
1657 sizestr = devstr + 1;
1658 *devstr = '\0';
1659 devstr = vol_args->name;
1660 ret = kstrtoull(devstr, 10, &devid);
1661 if (ret)
1662 goto out_free;
1663 if (!devid) {
1664 ret = -EINVAL;
1665 goto out_free;
1666 }
1667 btrfs_info(fs_info, "resizing devid %llu", devid);
1668 }
1669
1670 device = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
1671 if (!device) {
1672 btrfs_info(fs_info, "resizer unable to find device %llu",
1673 devid);
1674 ret = -ENODEV;
1675 goto out_free;
1676 }
1677
1678 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
1679 btrfs_info(fs_info,
1680 "resizer unable to apply on readonly device %llu",
1681 devid);
1682 ret = -EPERM;
1683 goto out_free;
1684 }
1685
1686 if (!strcmp(sizestr, "max"))
1687 new_size = device->bdev->bd_inode->i_size;
1688 else {
1689 if (sizestr[0] == '-') {
1690 mod = -1;
1691 sizestr++;
1692 } else if (sizestr[0] == '+') {
1693 mod = 1;
1694 sizestr++;
1695 }
1696 new_size = memparse(sizestr, &retptr);
1697 if (*retptr != '\0' || new_size == 0) {
1698 ret = -EINVAL;
1699 goto out_free;
1700 }
1701 }
1702
1703 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
1704 ret = -EPERM;
1705 goto out_free;
1706 }
1707
1708 old_size = btrfs_device_get_total_bytes(device);
1709
1710 if (mod < 0) {
1711 if (new_size > old_size) {
1712 ret = -EINVAL;
1713 goto out_free;
1714 }
1715 new_size = old_size - new_size;
1716 } else if (mod > 0) {
1717 if (new_size > ULLONG_MAX - old_size) {
1718 ret = -ERANGE;
1719 goto out_free;
1720 }
1721 new_size = old_size + new_size;
1722 }
1723
1724 if (new_size < SZ_256M) {
1725 ret = -EINVAL;
1726 goto out_free;
1727 }
1728 if (new_size > device->bdev->bd_inode->i_size) {
1729 ret = -EFBIG;
1730 goto out_free;
1731 }
1732
1733 new_size = round_down(new_size, fs_info->sectorsize);
1734
1735 if (new_size > old_size) {
1736 trans = btrfs_start_transaction(root, 0);
1737 if (IS_ERR(trans)) {
1738 ret = PTR_ERR(trans);
1739 goto out_free;
1740 }
1741 ret = btrfs_grow_device(trans, device, new_size);
1742 btrfs_commit_transaction(trans);
1743 } else if (new_size < old_size) {
1744 ret = btrfs_shrink_device(device, new_size);
1745 } /* equal, nothing need to do */
1746
1747 if (ret == 0 && new_size != old_size)
1748 btrfs_info_in_rcu(fs_info,
1749 "resize device %s (devid %llu) from %llu to %llu",
1750 rcu_str_deref(device->name), device->devid,
1751 old_size, new_size);
1752out_free:
1753 kfree(vol_args);
1754out:
1755 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
1756 mnt_drop_write_file(file);
1757 return ret;
1758}
1759
1760static noinline int __btrfs_ioctl_snap_create(struct file *file,
1761 const char *name, unsigned long fd, int subvol,
1762 bool readonly,
1763 struct btrfs_qgroup_inherit *inherit)
1764{
1765 int namelen;
1766 int ret = 0;
1767
1768 if (!S_ISDIR(file_inode(file)->i_mode))
1769 return -ENOTDIR;
1770
1771 ret = mnt_want_write_file(file);
1772 if (ret)
1773 goto out;
1774
1775 namelen = strlen(name);
1776 if (strchr(name, '/')) {
1777 ret = -EINVAL;
1778 goto out_drop_write;
1779 }
1780
1781 if (name[0] == '.' &&
1782 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1783 ret = -EEXIST;
1784 goto out_drop_write;
1785 }
1786
1787 if (subvol) {
1788 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1789 NULL, readonly, inherit);
1790 } else {
1791 struct fd src = fdget(fd);
1792 struct inode *src_inode;
1793 if (!src.file) {
1794 ret = -EINVAL;
1795 goto out_drop_write;
1796 }
1797
1798 src_inode = file_inode(src.file);
1799 if (src_inode->i_sb != file_inode(file)->i_sb) {
1800 btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
1801 "Snapshot src from another FS");
1802 ret = -EXDEV;
1803 } else if (!inode_owner_or_capable(src_inode)) {
1804 /*
1805 * Subvolume creation is not restricted, but snapshots
1806 * are limited to own subvolumes only
1807 */
1808 ret = -EPERM;
1809 } else {
1810 ret = btrfs_mksnapshot(&file->f_path, name, namelen,
1811 BTRFS_I(src_inode)->root,
1812 readonly, inherit);
1813 }
1814 fdput(src);
1815 }
1816out_drop_write:
1817 mnt_drop_write_file(file);
1818out:
1819 return ret;
1820}
1821
1822static noinline int btrfs_ioctl_snap_create(struct file *file,
1823 void __user *arg, int subvol)
1824{
1825 struct btrfs_ioctl_vol_args *vol_args;
1826 int ret;
1827
1828 if (!S_ISDIR(file_inode(file)->i_mode))
1829 return -ENOTDIR;
1830
1831 vol_args = memdup_user(arg, sizeof(*vol_args));
1832 if (IS_ERR(vol_args))
1833 return PTR_ERR(vol_args);
1834 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1835
1836 ret = __btrfs_ioctl_snap_create(file, vol_args->name, vol_args->fd,
1837 subvol, false, NULL);
1838
1839 kfree(vol_args);
1840 return ret;
1841}
1842
1843static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1844 void __user *arg, int subvol)
1845{
1846 struct btrfs_ioctl_vol_args_v2 *vol_args;
1847 int ret;
1848 bool readonly = false;
1849 struct btrfs_qgroup_inherit *inherit = NULL;
1850
1851 if (!S_ISDIR(file_inode(file)->i_mode))
1852 return -ENOTDIR;
1853
1854 vol_args = memdup_user(arg, sizeof(*vol_args));
1855 if (IS_ERR(vol_args))
1856 return PTR_ERR(vol_args);
1857 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1858
1859 if (vol_args->flags & ~BTRFS_SUBVOL_CREATE_ARGS_MASK) {
1860 ret = -EOPNOTSUPP;
1861 goto free_args;
1862 }
1863
1864 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1865 readonly = true;
1866 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1867 if (vol_args->size > PAGE_SIZE) {
1868 ret = -EINVAL;
1869 goto free_args;
1870 }
1871 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1872 if (IS_ERR(inherit)) {
1873 ret = PTR_ERR(inherit);
1874 goto free_args;
1875 }
1876 }
1877
1878 ret = __btrfs_ioctl_snap_create(file, vol_args->name, vol_args->fd,
1879 subvol, readonly, inherit);
1880 if (ret)
1881 goto free_inherit;
1882free_inherit:
1883 kfree(inherit);
1884free_args:
1885 kfree(vol_args);
1886 return ret;
1887}
1888
1889static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1890 void __user *arg)
1891{
1892 struct inode *inode = file_inode(file);
1893 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1894 struct btrfs_root *root = BTRFS_I(inode)->root;
1895 int ret = 0;
1896 u64 flags = 0;
1897
1898 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)
1899 return -EINVAL;
1900
1901 down_read(&fs_info->subvol_sem);
1902 if (btrfs_root_readonly(root))
1903 flags |= BTRFS_SUBVOL_RDONLY;
1904 up_read(&fs_info->subvol_sem);
1905
1906 if (copy_to_user(arg, &flags, sizeof(flags)))
1907 ret = -EFAULT;
1908
1909 return ret;
1910}
1911
1912static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1913 void __user *arg)
1914{
1915 struct inode *inode = file_inode(file);
1916 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1917 struct btrfs_root *root = BTRFS_I(inode)->root;
1918 struct btrfs_trans_handle *trans;
1919 u64 root_flags;
1920 u64 flags;
1921 int ret = 0;
1922
1923 if (!inode_owner_or_capable(inode))
1924 return -EPERM;
1925
1926 ret = mnt_want_write_file(file);
1927 if (ret)
1928 goto out;
1929
1930 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
1931 ret = -EINVAL;
1932 goto out_drop_write;
1933 }
1934
1935 if (copy_from_user(&flags, arg, sizeof(flags))) {
1936 ret = -EFAULT;
1937 goto out_drop_write;
1938 }
1939
1940 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1941 ret = -EOPNOTSUPP;
1942 goto out_drop_write;
1943 }
1944
1945 down_write(&fs_info->subvol_sem);
1946
1947 /* nothing to do */
1948 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1949 goto out_drop_sem;
1950
1951 root_flags = btrfs_root_flags(&root->root_item);
1952 if (flags & BTRFS_SUBVOL_RDONLY) {
1953 btrfs_set_root_flags(&root->root_item,
1954 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1955 } else {
1956 /*
1957 * Block RO -> RW transition if this subvolume is involved in
1958 * send
1959 */
1960 spin_lock(&root->root_item_lock);
1961 if (root->send_in_progress == 0) {
1962 btrfs_set_root_flags(&root->root_item,
1963 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1964 spin_unlock(&root->root_item_lock);
1965 } else {
1966 spin_unlock(&root->root_item_lock);
1967 btrfs_warn(fs_info,
1968 "Attempt to set subvolume %llu read-write during send",
1969 root->root_key.objectid);
1970 ret = -EPERM;
1971 goto out_drop_sem;
1972 }
1973 }
1974
1975 trans = btrfs_start_transaction(root, 1);
1976 if (IS_ERR(trans)) {
1977 ret = PTR_ERR(trans);
1978 goto out_reset;
1979 }
1980
1981 ret = btrfs_update_root(trans, fs_info->tree_root,
1982 &root->root_key, &root->root_item);
1983 if (ret < 0) {
1984 btrfs_end_transaction(trans);
1985 goto out_reset;
1986 }
1987
1988 ret = btrfs_commit_transaction(trans);
1989
1990out_reset:
1991 if (ret)
1992 btrfs_set_root_flags(&root->root_item, root_flags);
1993out_drop_sem:
1994 up_write(&fs_info->subvol_sem);
1995out_drop_write:
1996 mnt_drop_write_file(file);
1997out:
1998 return ret;
1999}
2000
2001static noinline int key_in_sk(struct btrfs_key *key,
2002 struct btrfs_ioctl_search_key *sk)
2003{
2004 struct btrfs_key test;
2005 int ret;
2006
2007 test.objectid = sk->min_objectid;
2008 test.type = sk->min_type;
2009 test.offset = sk->min_offset;
2010
2011 ret = btrfs_comp_cpu_keys(key, &test);
2012 if (ret < 0)
2013 return 0;
2014
2015 test.objectid = sk->max_objectid;
2016 test.type = sk->max_type;
2017 test.offset = sk->max_offset;
2018
2019 ret = btrfs_comp_cpu_keys(key, &test);
2020 if (ret > 0)
2021 return 0;
2022 return 1;
2023}
2024
2025static noinline int copy_to_sk(struct btrfs_path *path,
2026 struct btrfs_key *key,
2027 struct btrfs_ioctl_search_key *sk,
2028 size_t *buf_size,
2029 char __user *ubuf,
2030 unsigned long *sk_offset,
2031 int *num_found)
2032{
2033 u64 found_transid;
2034 struct extent_buffer *leaf;
2035 struct btrfs_ioctl_search_header sh;
2036 struct btrfs_key test;
2037 unsigned long item_off;
2038 unsigned long item_len;
2039 int nritems;
2040 int i;
2041 int slot;
2042 int ret = 0;
2043
2044 leaf = path->nodes[0];
2045 slot = path->slots[0];
2046 nritems = btrfs_header_nritems(leaf);
2047
2048 if (btrfs_header_generation(leaf) > sk->max_transid) {
2049 i = nritems;
2050 goto advance_key;
2051 }
2052 found_transid = btrfs_header_generation(leaf);
2053
2054 for (i = slot; i < nritems; i++) {
2055 item_off = btrfs_item_ptr_offset(leaf, i);
2056 item_len = btrfs_item_size_nr(leaf, i);
2057
2058 btrfs_item_key_to_cpu(leaf, key, i);
2059 if (!key_in_sk(key, sk))
2060 continue;
2061
2062 if (sizeof(sh) + item_len > *buf_size) {
2063 if (*num_found) {
2064 ret = 1;
2065 goto out;
2066 }
2067
2068 /*
2069 * return one empty item back for v1, which does not
2070 * handle -EOVERFLOW
2071 */
2072
2073 *buf_size = sizeof(sh) + item_len;
2074 item_len = 0;
2075 ret = -EOVERFLOW;
2076 }
2077
2078 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2079 ret = 1;
2080 goto out;
2081 }
2082
2083 sh.objectid = key->objectid;
2084 sh.offset = key->offset;
2085 sh.type = key->type;
2086 sh.len = item_len;
2087 sh.transid = found_transid;
2088
2089 /*
2090 * Copy search result header. If we fault then loop again so we
2091 * can fault in the pages and -EFAULT there if there's a
2092 * problem. Otherwise we'll fault and then copy the buffer in
2093 * properly this next time through
2094 */
2095 if (copy_to_user_nofault(ubuf + *sk_offset, &sh, sizeof(sh))) {
2096 ret = 0;
2097 goto out;
2098 }
2099
2100 *sk_offset += sizeof(sh);
2101
2102 if (item_len) {
2103 char __user *up = ubuf + *sk_offset;
2104 /*
2105 * Copy the item, same behavior as above, but reset the
2106 * * sk_offset so we copy the full thing again.
2107 */
2108 if (read_extent_buffer_to_user_nofault(leaf, up,
2109 item_off, item_len)) {
2110 ret = 0;
2111 *sk_offset -= sizeof(sh);
2112 goto out;
2113 }
2114
2115 *sk_offset += item_len;
2116 }
2117 (*num_found)++;
2118
2119 if (ret) /* -EOVERFLOW from above */
2120 goto out;
2121
2122 if (*num_found >= sk->nr_items) {
2123 ret = 1;
2124 goto out;
2125 }
2126 }
2127advance_key:
2128 ret = 0;
2129 test.objectid = sk->max_objectid;
2130 test.type = sk->max_type;
2131 test.offset = sk->max_offset;
2132 if (btrfs_comp_cpu_keys(key, &test) >= 0)
2133 ret = 1;
2134 else if (key->offset < (u64)-1)
2135 key->offset++;
2136 else if (key->type < (u8)-1) {
2137 key->offset = 0;
2138 key->type++;
2139 } else if (key->objectid < (u64)-1) {
2140 key->offset = 0;
2141 key->type = 0;
2142 key->objectid++;
2143 } else
2144 ret = 1;
2145out:
2146 /*
2147 * 0: all items from this leaf copied, continue with next
2148 * 1: * more items can be copied, but unused buffer is too small
2149 * * all items were found
2150 * Either way, it will stops the loop which iterates to the next
2151 * leaf
2152 * -EOVERFLOW: item was to large for buffer
2153 * -EFAULT: could not copy extent buffer back to userspace
2154 */
2155 return ret;
2156}
2157
2158static noinline int search_ioctl(struct inode *inode,
2159 struct btrfs_ioctl_search_key *sk,
2160 size_t *buf_size,
2161 char __user *ubuf)
2162{
2163 struct btrfs_fs_info *info = btrfs_sb(inode->i_sb);
2164 struct btrfs_root *root;
2165 struct btrfs_key key;
2166 struct btrfs_path *path;
2167 int ret;
2168 int num_found = 0;
2169 unsigned long sk_offset = 0;
2170
2171 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2172 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2173 return -EOVERFLOW;
2174 }
2175
2176 path = btrfs_alloc_path();
2177 if (!path)
2178 return -ENOMEM;
2179
2180 if (sk->tree_id == 0) {
2181 /* search the root of the inode that was passed */
2182 root = btrfs_grab_root(BTRFS_I(inode)->root);
2183 } else {
2184 root = btrfs_get_fs_root(info, sk->tree_id, true);
2185 if (IS_ERR(root)) {
2186 btrfs_free_path(path);
2187 return PTR_ERR(root);
2188 }
2189 }
2190
2191 key.objectid = sk->min_objectid;
2192 key.type = sk->min_type;
2193 key.offset = sk->min_offset;
2194
2195 while (1) {
2196 ret = fault_in_pages_writeable(ubuf + sk_offset,
2197 *buf_size - sk_offset);
2198 if (ret)
2199 break;
2200
2201 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2202 if (ret != 0) {
2203 if (ret > 0)
2204 ret = 0;
2205 goto err;
2206 }
2207 ret = copy_to_sk(path, &key, sk, buf_size, ubuf,
2208 &sk_offset, &num_found);
2209 btrfs_release_path(path);
2210 if (ret)
2211 break;
2212
2213 }
2214 if (ret > 0)
2215 ret = 0;
2216err:
2217 sk->nr_items = num_found;
2218 btrfs_put_root(root);
2219 btrfs_free_path(path);
2220 return ret;
2221}
2222
2223static noinline int btrfs_ioctl_tree_search(struct file *file,
2224 void __user *argp)
2225{
2226 struct btrfs_ioctl_search_args __user *uargs;
2227 struct btrfs_ioctl_search_key sk;
2228 struct inode *inode;
2229 int ret;
2230 size_t buf_size;
2231
2232 if (!capable(CAP_SYS_ADMIN))
2233 return -EPERM;
2234
2235 uargs = (struct btrfs_ioctl_search_args __user *)argp;
2236
2237 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2238 return -EFAULT;
2239
2240 buf_size = sizeof(uargs->buf);
2241
2242 inode = file_inode(file);
2243 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2244
2245 /*
2246 * In the origin implementation an overflow is handled by returning a
2247 * search header with a len of zero, so reset ret.
2248 */
2249 if (ret == -EOVERFLOW)
2250 ret = 0;
2251
2252 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2253 ret = -EFAULT;
2254 return ret;
2255}
2256
2257static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2258 void __user *argp)
2259{
2260 struct btrfs_ioctl_search_args_v2 __user *uarg;
2261 struct btrfs_ioctl_search_args_v2 args;
2262 struct inode *inode;
2263 int ret;
2264 size_t buf_size;
2265 const size_t buf_limit = SZ_16M;
2266
2267 if (!capable(CAP_SYS_ADMIN))
2268 return -EPERM;
2269
2270 /* copy search header and buffer size */
2271 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2272 if (copy_from_user(&args, uarg, sizeof(args)))
2273 return -EFAULT;
2274
2275 buf_size = args.buf_size;
2276
2277 /* limit result size to 16MB */
2278 if (buf_size > buf_limit)
2279 buf_size = buf_limit;
2280
2281 inode = file_inode(file);
2282 ret = search_ioctl(inode, &args.key, &buf_size,
2283 (char __user *)(&uarg->buf[0]));
2284 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2285 ret = -EFAULT;
2286 else if (ret == -EOVERFLOW &&
2287 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2288 ret = -EFAULT;
2289
2290 return ret;
2291}
2292
2293/*
2294 * Search INODE_REFs to identify path name of 'dirid' directory
2295 * in a 'tree_id' tree. and sets path name to 'name'.
2296 */
2297static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2298 u64 tree_id, u64 dirid, char *name)
2299{
2300 struct btrfs_root *root;
2301 struct btrfs_key key;
2302 char *ptr;
2303 int ret = -1;
2304 int slot;
2305 int len;
2306 int total_len = 0;
2307 struct btrfs_inode_ref *iref;
2308 struct extent_buffer *l;
2309 struct btrfs_path *path;
2310
2311 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2312 name[0]='\0';
2313 return 0;
2314 }
2315
2316 path = btrfs_alloc_path();
2317 if (!path)
2318 return -ENOMEM;
2319
2320 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1];
2321
2322 root = btrfs_get_fs_root(info, tree_id, true);
2323 if (IS_ERR(root)) {
2324 ret = PTR_ERR(root);
2325 root = NULL;
2326 goto out;
2327 }
2328
2329 key.objectid = dirid;
2330 key.type = BTRFS_INODE_REF_KEY;
2331 key.offset = (u64)-1;
2332
2333 while (1) {
2334 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2335 if (ret < 0)
2336 goto out;
2337 else if (ret > 0) {
2338 ret = btrfs_previous_item(root, path, dirid,
2339 BTRFS_INODE_REF_KEY);
2340 if (ret < 0)
2341 goto out;
2342 else if (ret > 0) {
2343 ret = -ENOENT;
2344 goto out;
2345 }
2346 }
2347
2348 l = path->nodes[0];
2349 slot = path->slots[0];
2350 btrfs_item_key_to_cpu(l, &key, slot);
2351
2352 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2353 len = btrfs_inode_ref_name_len(l, iref);
2354 ptr -= len + 1;
2355 total_len += len + 1;
2356 if (ptr < name) {
2357 ret = -ENAMETOOLONG;
2358 goto out;
2359 }
2360
2361 *(ptr + len) = '/';
2362 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2363
2364 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2365 break;
2366
2367 btrfs_release_path(path);
2368 key.objectid = key.offset;
2369 key.offset = (u64)-1;
2370 dirid = key.objectid;
2371 }
2372 memmove(name, ptr, total_len);
2373 name[total_len] = '\0';
2374 ret = 0;
2375out:
2376 btrfs_put_root(root);
2377 btrfs_free_path(path);
2378 return ret;
2379}
2380
2381static int btrfs_search_path_in_tree_user(struct inode *inode,
2382 struct btrfs_ioctl_ino_lookup_user_args *args)
2383{
2384 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2385 struct super_block *sb = inode->i_sb;
2386 struct btrfs_key upper_limit = BTRFS_I(inode)->location;
2387 u64 treeid = BTRFS_I(inode)->root->root_key.objectid;
2388 u64 dirid = args->dirid;
2389 unsigned long item_off;
2390 unsigned long item_len;
2391 struct btrfs_inode_ref *iref;
2392 struct btrfs_root_ref *rref;
2393 struct btrfs_root *root = NULL;
2394 struct btrfs_path *path;
2395 struct btrfs_key key, key2;
2396 struct extent_buffer *leaf;
2397 struct inode *temp_inode;
2398 char *ptr;
2399 int slot;
2400 int len;
2401 int total_len = 0;
2402 int ret;
2403
2404 path = btrfs_alloc_path();
2405 if (!path)
2406 return -ENOMEM;
2407
2408 /*
2409 * If the bottom subvolume does not exist directly under upper_limit,
2410 * construct the path in from the bottom up.
2411 */
2412 if (dirid != upper_limit.objectid) {
2413 ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1];
2414
2415 root = btrfs_get_fs_root(fs_info, treeid, true);
2416 if (IS_ERR(root)) {
2417 ret = PTR_ERR(root);
2418 goto out;
2419 }
2420
2421 key.objectid = dirid;
2422 key.type = BTRFS_INODE_REF_KEY;
2423 key.offset = (u64)-1;
2424 while (1) {
2425 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2426 if (ret < 0) {
2427 goto out_put;
2428 } else if (ret > 0) {
2429 ret = btrfs_previous_item(root, path, dirid,
2430 BTRFS_INODE_REF_KEY);
2431 if (ret < 0) {
2432 goto out_put;
2433 } else if (ret > 0) {
2434 ret = -ENOENT;
2435 goto out_put;
2436 }
2437 }
2438
2439 leaf = path->nodes[0];
2440 slot = path->slots[0];
2441 btrfs_item_key_to_cpu(leaf, &key, slot);
2442
2443 iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref);
2444 len = btrfs_inode_ref_name_len(leaf, iref);
2445 ptr -= len + 1;
2446 total_len += len + 1;
2447 if (ptr < args->path) {
2448 ret = -ENAMETOOLONG;
2449 goto out_put;
2450 }
2451
2452 *(ptr + len) = '/';
2453 read_extent_buffer(leaf, ptr,
2454 (unsigned long)(iref + 1), len);
2455
2456 /* Check the read+exec permission of this directory */
2457 ret = btrfs_previous_item(root, path, dirid,
2458 BTRFS_INODE_ITEM_KEY);
2459 if (ret < 0) {
2460 goto out_put;
2461 } else if (ret > 0) {
2462 ret = -ENOENT;
2463 goto out_put;
2464 }
2465
2466 leaf = path->nodes[0];
2467 slot = path->slots[0];
2468 btrfs_item_key_to_cpu(leaf, &key2, slot);
2469 if (key2.objectid != dirid) {
2470 ret = -ENOENT;
2471 goto out_put;
2472 }
2473
2474 temp_inode = btrfs_iget(sb, key2.objectid, root);
2475 if (IS_ERR(temp_inode)) {
2476 ret = PTR_ERR(temp_inode);
2477 goto out_put;
2478 }
2479 ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC);
2480 iput(temp_inode);
2481 if (ret) {
2482 ret = -EACCES;
2483 goto out_put;
2484 }
2485
2486 if (key.offset == upper_limit.objectid)
2487 break;
2488 if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {
2489 ret = -EACCES;
2490 goto out_put;
2491 }
2492
2493 btrfs_release_path(path);
2494 key.objectid = key.offset;
2495 key.offset = (u64)-1;
2496 dirid = key.objectid;
2497 }
2498
2499 memmove(args->path, ptr, total_len);
2500 args->path[total_len] = '\0';
2501 btrfs_put_root(root);
2502 root = NULL;
2503 btrfs_release_path(path);
2504 }
2505
2506 /* Get the bottom subvolume's name from ROOT_REF */
2507 key.objectid = treeid;
2508 key.type = BTRFS_ROOT_REF_KEY;
2509 key.offset = args->treeid;
2510 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
2511 if (ret < 0) {
2512 goto out;
2513 } else if (ret > 0) {
2514 ret = -ENOENT;
2515 goto out;
2516 }
2517
2518 leaf = path->nodes[0];
2519 slot = path->slots[0];
2520 btrfs_item_key_to_cpu(leaf, &key, slot);
2521
2522 item_off = btrfs_item_ptr_offset(leaf, slot);
2523 item_len = btrfs_item_size_nr(leaf, slot);
2524 /* Check if dirid in ROOT_REF corresponds to passed dirid */
2525 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2526 if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) {
2527 ret = -EINVAL;
2528 goto out;
2529 }
2530
2531 /* Copy subvolume's name */
2532 item_off += sizeof(struct btrfs_root_ref);
2533 item_len -= sizeof(struct btrfs_root_ref);
2534 read_extent_buffer(leaf, args->name, item_off, item_len);
2535 args->name[item_len] = 0;
2536
2537out_put:
2538 btrfs_put_root(root);
2539out:
2540 btrfs_free_path(path);
2541 return ret;
2542}
2543
2544static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2545 void __user *argp)
2546{
2547 struct btrfs_ioctl_ino_lookup_args *args;
2548 struct inode *inode;
2549 int ret = 0;
2550
2551 args = memdup_user(argp, sizeof(*args));
2552 if (IS_ERR(args))
2553 return PTR_ERR(args);
2554
2555 inode = file_inode(file);
2556
2557 /*
2558 * Unprivileged query to obtain the containing subvolume root id. The
2559 * path is reset so it's consistent with btrfs_search_path_in_tree.
2560 */
2561 if (args->treeid == 0)
2562 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2563
2564 if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2565 args->name[0] = 0;
2566 goto out;
2567 }
2568
2569 if (!capable(CAP_SYS_ADMIN)) {
2570 ret = -EPERM;
2571 goto out;
2572 }
2573
2574 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2575 args->treeid, args->objectid,
2576 args->name);
2577
2578out:
2579 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2580 ret = -EFAULT;
2581
2582 kfree(args);
2583 return ret;
2584}
2585
2586/*
2587 * Version of ino_lookup ioctl (unprivileged)
2588 *
2589 * The main differences from ino_lookup ioctl are:
2590 *
2591 * 1. Read + Exec permission will be checked using inode_permission() during
2592 * path construction. -EACCES will be returned in case of failure.
2593 * 2. Path construction will be stopped at the inode number which corresponds
2594 * to the fd with which this ioctl is called. If constructed path does not
2595 * exist under fd's inode, -EACCES will be returned.
2596 * 3. The name of bottom subvolume is also searched and filled.
2597 */
2598static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp)
2599{
2600 struct btrfs_ioctl_ino_lookup_user_args *args;
2601 struct inode *inode;
2602 int ret;
2603
2604 args = memdup_user(argp, sizeof(*args));
2605 if (IS_ERR(args))
2606 return PTR_ERR(args);
2607
2608 inode = file_inode(file);
2609
2610 if (args->dirid == BTRFS_FIRST_FREE_OBJECTID &&
2611 BTRFS_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) {
2612 /*
2613 * The subvolume does not exist under fd with which this is
2614 * called
2615 */
2616 kfree(args);
2617 return -EACCES;
2618 }
2619
2620 ret = btrfs_search_path_in_tree_user(inode, args);
2621
2622 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2623 ret = -EFAULT;
2624
2625 kfree(args);
2626 return ret;
2627}
2628
2629/* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */
2630static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp)
2631{
2632 struct btrfs_ioctl_get_subvol_info_args *subvol_info;
2633 struct btrfs_fs_info *fs_info;
2634 struct btrfs_root *root;
2635 struct btrfs_path *path;
2636 struct btrfs_key key;
2637 struct btrfs_root_item *root_item;
2638 struct btrfs_root_ref *rref;
2639 struct extent_buffer *leaf;
2640 unsigned long item_off;
2641 unsigned long item_len;
2642 struct inode *inode;
2643 int slot;
2644 int ret = 0;
2645
2646 path = btrfs_alloc_path();
2647 if (!path)
2648 return -ENOMEM;
2649
2650 subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL);
2651 if (!subvol_info) {
2652 btrfs_free_path(path);
2653 return -ENOMEM;
2654 }
2655
2656 inode = file_inode(file);
2657 fs_info = BTRFS_I(inode)->root->fs_info;
2658
2659 /* Get root_item of inode's subvolume */
2660 key.objectid = BTRFS_I(inode)->root->root_key.objectid;
2661 root = btrfs_get_fs_root(fs_info, key.objectid, true);
2662 if (IS_ERR(root)) {
2663 ret = PTR_ERR(root);
2664 goto out_free;
2665 }
2666 root_item = &root->root_item;
2667
2668 subvol_info->treeid = key.objectid;
2669
2670 subvol_info->generation = btrfs_root_generation(root_item);
2671 subvol_info->flags = btrfs_root_flags(root_item);
2672
2673 memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE);
2674 memcpy(subvol_info->parent_uuid, root_item->parent_uuid,
2675 BTRFS_UUID_SIZE);
2676 memcpy(subvol_info->received_uuid, root_item->received_uuid,
2677 BTRFS_UUID_SIZE);
2678
2679 subvol_info->ctransid = btrfs_root_ctransid(root_item);
2680 subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime);
2681 subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime);
2682
2683 subvol_info->otransid = btrfs_root_otransid(root_item);
2684 subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime);
2685 subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime);
2686
2687 subvol_info->stransid = btrfs_root_stransid(root_item);
2688 subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime);
2689 subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime);
2690
2691 subvol_info->rtransid = btrfs_root_rtransid(root_item);
2692 subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime);
2693 subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime);
2694
2695 if (key.objectid != BTRFS_FS_TREE_OBJECTID) {
2696 /* Search root tree for ROOT_BACKREF of this subvolume */
2697 key.type = BTRFS_ROOT_BACKREF_KEY;
2698 key.offset = 0;
2699 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
2700 if (ret < 0) {
2701 goto out;
2702 } else if (path->slots[0] >=
2703 btrfs_header_nritems(path->nodes[0])) {
2704 ret = btrfs_next_leaf(fs_info->tree_root, path);
2705 if (ret < 0) {
2706 goto out;
2707 } else if (ret > 0) {
2708 ret = -EUCLEAN;
2709 goto out;
2710 }
2711 }
2712
2713 leaf = path->nodes[0];
2714 slot = path->slots[0];
2715 btrfs_item_key_to_cpu(leaf, &key, slot);
2716 if (key.objectid == subvol_info->treeid &&
2717 key.type == BTRFS_ROOT_BACKREF_KEY) {
2718 subvol_info->parent_id = key.offset;
2719
2720 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2721 subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref);
2722
2723 item_off = btrfs_item_ptr_offset(leaf, slot)
2724 + sizeof(struct btrfs_root_ref);
2725 item_len = btrfs_item_size_nr(leaf, slot)
2726 - sizeof(struct btrfs_root_ref);
2727 read_extent_buffer(leaf, subvol_info->name,
2728 item_off, item_len);
2729 } else {
2730 ret = -ENOENT;
2731 goto out;
2732 }
2733 }
2734
2735 if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))
2736 ret = -EFAULT;
2737
2738out:
2739 btrfs_put_root(root);
2740out_free:
2741 btrfs_free_path(path);
2742 kfree(subvol_info);
2743 return ret;
2744}
2745
2746/*
2747 * Return ROOT_REF information of the subvolume containing this inode
2748 * except the subvolume name.
2749 */
2750static int btrfs_ioctl_get_subvol_rootref(struct file *file, void __user *argp)
2751{
2752 struct btrfs_ioctl_get_subvol_rootref_args *rootrefs;
2753 struct btrfs_root_ref *rref;
2754 struct btrfs_root *root;
2755 struct btrfs_path *path;
2756 struct btrfs_key key;
2757 struct extent_buffer *leaf;
2758 struct inode *inode;
2759 u64 objectid;
2760 int slot;
2761 int ret;
2762 u8 found;
2763
2764 path = btrfs_alloc_path();
2765 if (!path)
2766 return -ENOMEM;
2767
2768 rootrefs = memdup_user(argp, sizeof(*rootrefs));
2769 if (IS_ERR(rootrefs)) {
2770 btrfs_free_path(path);
2771 return PTR_ERR(rootrefs);
2772 }
2773
2774 inode = file_inode(file);
2775 root = BTRFS_I(inode)->root->fs_info->tree_root;
2776 objectid = BTRFS_I(inode)->root->root_key.objectid;
2777
2778 key.objectid = objectid;
2779 key.type = BTRFS_ROOT_REF_KEY;
2780 key.offset = rootrefs->min_treeid;
2781 found = 0;
2782
2783 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2784 if (ret < 0) {
2785 goto out;
2786 } else if (path->slots[0] >=
2787 btrfs_header_nritems(path->nodes[0])) {
2788 ret = btrfs_next_leaf(root, path);
2789 if (ret < 0) {
2790 goto out;
2791 } else if (ret > 0) {
2792 ret = -EUCLEAN;
2793 goto out;
2794 }
2795 }
2796 while (1) {
2797 leaf = path->nodes[0];
2798 slot = path->slots[0];
2799
2800 btrfs_item_key_to_cpu(leaf, &key, slot);
2801 if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) {
2802 ret = 0;
2803 goto out;
2804 }
2805
2806 if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) {
2807 ret = -EOVERFLOW;
2808 goto out;
2809 }
2810
2811 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2812 rootrefs->rootref[found].treeid = key.offset;
2813 rootrefs->rootref[found].dirid =
2814 btrfs_root_ref_dirid(leaf, rref);
2815 found++;
2816
2817 ret = btrfs_next_item(root, path);
2818 if (ret < 0) {
2819 goto out;
2820 } else if (ret > 0) {
2821 ret = -EUCLEAN;
2822 goto out;
2823 }
2824 }
2825
2826out:
2827 if (!ret || ret == -EOVERFLOW) {
2828 rootrefs->num_items = found;
2829 /* update min_treeid for next search */
2830 if (found)
2831 rootrefs->min_treeid =
2832 rootrefs->rootref[found - 1].treeid + 1;
2833 if (copy_to_user(argp, rootrefs, sizeof(*rootrefs)))
2834 ret = -EFAULT;
2835 }
2836
2837 kfree(rootrefs);
2838 btrfs_free_path(path);
2839
2840 return ret;
2841}
2842
2843static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2844 void __user *arg,
2845 bool destroy_v2)
2846{
2847 struct dentry *parent = file->f_path.dentry;
2848 struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb);
2849 struct dentry *dentry;
2850 struct inode *dir = d_inode(parent);
2851 struct inode *inode;
2852 struct btrfs_root *root = BTRFS_I(dir)->root;
2853 struct btrfs_root *dest = NULL;
2854 struct btrfs_ioctl_vol_args *vol_args = NULL;
2855 struct btrfs_ioctl_vol_args_v2 *vol_args2 = NULL;
2856 char *subvol_name, *subvol_name_ptr = NULL;
2857 int subvol_namelen;
2858 int err = 0;
2859 bool destroy_parent = false;
2860
2861 if (destroy_v2) {
2862 vol_args2 = memdup_user(arg, sizeof(*vol_args2));
2863 if (IS_ERR(vol_args2))
2864 return PTR_ERR(vol_args2);
2865
2866 if (vol_args2->flags & ~BTRFS_SUBVOL_DELETE_ARGS_MASK) {
2867 err = -EOPNOTSUPP;
2868 goto out;
2869 }
2870
2871 /*
2872 * If SPEC_BY_ID is not set, we are looking for the subvolume by
2873 * name, same as v1 currently does.
2874 */
2875 if (!(vol_args2->flags & BTRFS_SUBVOL_SPEC_BY_ID)) {
2876 vol_args2->name[BTRFS_SUBVOL_NAME_MAX] = 0;
2877 subvol_name = vol_args2->name;
2878
2879 err = mnt_want_write_file(file);
2880 if (err)
2881 goto out;
2882 } else {
2883 if (vol_args2->subvolid < BTRFS_FIRST_FREE_OBJECTID) {
2884 err = -EINVAL;
2885 goto out;
2886 }
2887
2888 err = mnt_want_write_file(file);
2889 if (err)
2890 goto out;
2891
2892 dentry = btrfs_get_dentry(fs_info->sb,
2893 BTRFS_FIRST_FREE_OBJECTID,
2894 vol_args2->subvolid, 0, 0);
2895 if (IS_ERR(dentry)) {
2896 err = PTR_ERR(dentry);
2897 goto out_drop_write;
2898 }
2899
2900 /*
2901 * Change the default parent since the subvolume being
2902 * deleted can be outside of the current mount point.
2903 */
2904 parent = btrfs_get_parent(dentry);
2905
2906 /*
2907 * At this point dentry->d_name can point to '/' if the
2908 * subvolume we want to destroy is outsite of the
2909 * current mount point, so we need to release the
2910 * current dentry and execute the lookup to return a new
2911 * one with ->d_name pointing to the
2912 * <mount point>/subvol_name.
2913 */
2914 dput(dentry);
2915 if (IS_ERR(parent)) {
2916 err = PTR_ERR(parent);
2917 goto out_drop_write;
2918 }
2919 dir = d_inode(parent);
2920
2921 /*
2922 * If v2 was used with SPEC_BY_ID, a new parent was
2923 * allocated since the subvolume can be outside of the
2924 * current mount point. Later on we need to release this
2925 * new parent dentry.
2926 */
2927 destroy_parent = true;
2928
2929 subvol_name_ptr = btrfs_get_subvol_name_from_objectid(
2930 fs_info, vol_args2->subvolid);
2931 if (IS_ERR(subvol_name_ptr)) {
2932 err = PTR_ERR(subvol_name_ptr);
2933 goto free_parent;
2934 }
2935 /* subvol_name_ptr is already NULL termined */
2936 subvol_name = (char *)kbasename(subvol_name_ptr);
2937 }
2938 } else {
2939 vol_args = memdup_user(arg, sizeof(*vol_args));
2940 if (IS_ERR(vol_args))
2941 return PTR_ERR(vol_args);
2942
2943 vol_args->name[BTRFS_PATH_NAME_MAX] = 0;
2944 subvol_name = vol_args->name;
2945
2946 err = mnt_want_write_file(file);
2947 if (err)
2948 goto out;
2949 }
2950
2951 subvol_namelen = strlen(subvol_name);
2952
2953 if (strchr(subvol_name, '/') ||
2954 strncmp(subvol_name, "..", subvol_namelen) == 0) {
2955 err = -EINVAL;
2956 goto free_subvol_name;
2957 }
2958
2959 if (!S_ISDIR(dir->i_mode)) {
2960 err = -ENOTDIR;
2961 goto free_subvol_name;
2962 }
2963
2964 err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
2965 if (err == -EINTR)
2966 goto free_subvol_name;
2967 dentry = lookup_one_len(subvol_name, parent, subvol_namelen);
2968 if (IS_ERR(dentry)) {
2969 err = PTR_ERR(dentry);
2970 goto out_unlock_dir;
2971 }
2972
2973 if (d_really_is_negative(dentry)) {
2974 err = -ENOENT;
2975 goto out_dput;
2976 }
2977
2978 inode = d_inode(dentry);
2979 dest = BTRFS_I(inode)->root;
2980 if (!capable(CAP_SYS_ADMIN)) {
2981 /*
2982 * Regular user. Only allow this with a special mount
2983 * option, when the user has write+exec access to the
2984 * subvol root, and when rmdir(2) would have been
2985 * allowed.
2986 *
2987 * Note that this is _not_ check that the subvol is
2988 * empty or doesn't contain data that we wouldn't
2989 * otherwise be able to delete.
2990 *
2991 * Users who want to delete empty subvols should try
2992 * rmdir(2).
2993 */
2994 err = -EPERM;
2995 if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))
2996 goto out_dput;
2997
2998 /*
2999 * Do not allow deletion if the parent dir is the same
3000 * as the dir to be deleted. That means the ioctl
3001 * must be called on the dentry referencing the root
3002 * of the subvol, not a random directory contained
3003 * within it.
3004 */
3005 err = -EINVAL;
3006 if (root == dest)
3007 goto out_dput;
3008
3009 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
3010 if (err)
3011 goto out_dput;
3012 }
3013
3014 /* check if subvolume may be deleted by a user */
3015 err = btrfs_may_delete(dir, dentry, 1);
3016 if (err)
3017 goto out_dput;
3018
3019 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
3020 err = -EINVAL;
3021 goto out_dput;
3022 }
3023
3024 inode_lock(inode);
3025 err = btrfs_delete_subvolume(dir, dentry);
3026 inode_unlock(inode);
3027 if (!err) {
3028 fsnotify_rmdir(dir, dentry);
3029 d_delete(dentry);
3030 }
3031
3032out_dput:
3033 dput(dentry);
3034out_unlock_dir:
3035 inode_unlock(dir);
3036free_subvol_name:
3037 kfree(subvol_name_ptr);
3038free_parent:
3039 if (destroy_parent)
3040 dput(parent);
3041out_drop_write:
3042 mnt_drop_write_file(file);
3043out:
3044 kfree(vol_args2);
3045 kfree(vol_args);
3046 return err;
3047}
3048
3049static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
3050{
3051 struct inode *inode = file_inode(file);
3052 struct btrfs_root *root = BTRFS_I(inode)->root;
3053 struct btrfs_ioctl_defrag_range_args *range;
3054 int ret;
3055
3056 ret = mnt_want_write_file(file);
3057 if (ret)
3058 return ret;
3059
3060 if (btrfs_root_readonly(root)) {
3061 ret = -EROFS;
3062 goto out;
3063 }
3064
3065 switch (inode->i_mode & S_IFMT) {
3066 case S_IFDIR:
3067 if (!capable(CAP_SYS_ADMIN)) {
3068 ret = -EPERM;
3069 goto out;
3070 }
3071 ret = btrfs_defrag_root(root);
3072 break;
3073 case S_IFREG:
3074 /*
3075 * Note that this does not check the file descriptor for write
3076 * access. This prevents defragmenting executables that are
3077 * running and allows defrag on files open in read-only mode.
3078 */
3079 if (!capable(CAP_SYS_ADMIN) &&
3080 inode_permission(inode, MAY_WRITE)) {
3081 ret = -EPERM;
3082 goto out;
3083 }
3084
3085 range = kzalloc(sizeof(*range), GFP_KERNEL);
3086 if (!range) {
3087 ret = -ENOMEM;
3088 goto out;
3089 }
3090
3091 if (argp) {
3092 if (copy_from_user(range, argp,
3093 sizeof(*range))) {
3094 ret = -EFAULT;
3095 kfree(range);
3096 goto out;
3097 }
3098 /* compression requires us to start the IO */
3099 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
3100 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
3101 range->extent_thresh = (u32)-1;
3102 }
3103 } else {
3104 /* the rest are all set to zero by kzalloc */
3105 range->len = (u64)-1;
3106 }
3107 ret = btrfs_defrag_file(file_inode(file), file,
3108 range, BTRFS_OLDEST_GENERATION, 0);
3109 if (ret > 0)
3110 ret = 0;
3111 kfree(range);
3112 break;
3113 default:
3114 ret = -EINVAL;
3115 }
3116out:
3117 mnt_drop_write_file(file);
3118 return ret;
3119}
3120
3121static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg)
3122{
3123 struct btrfs_ioctl_vol_args *vol_args;
3124 int ret;
3125
3126 if (!capable(CAP_SYS_ADMIN))
3127 return -EPERM;
3128
3129 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags))
3130 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3131
3132 vol_args = memdup_user(arg, sizeof(*vol_args));
3133 if (IS_ERR(vol_args)) {
3134 ret = PTR_ERR(vol_args);
3135 goto out;
3136 }
3137
3138 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3139 ret = btrfs_init_new_device(fs_info, vol_args->name);
3140
3141 if (!ret)
3142 btrfs_info(fs_info, "disk added %s", vol_args->name);
3143
3144 kfree(vol_args);
3145out:
3146 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3147 return ret;
3148}
3149
3150static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
3151{
3152 struct inode *inode = file_inode(file);
3153 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3154 struct btrfs_ioctl_vol_args_v2 *vol_args;
3155 int ret;
3156
3157 if (!capable(CAP_SYS_ADMIN))
3158 return -EPERM;
3159
3160 ret = mnt_want_write_file(file);
3161 if (ret)
3162 return ret;
3163
3164 vol_args = memdup_user(arg, sizeof(*vol_args));
3165 if (IS_ERR(vol_args)) {
3166 ret = PTR_ERR(vol_args);
3167 goto err_drop;
3168 }
3169
3170 if (vol_args->flags & ~BTRFS_DEVICE_REMOVE_ARGS_MASK) {
3171 ret = -EOPNOTSUPP;
3172 goto out;
3173 }
3174
3175 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
3176 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3177 goto out;
3178 }
3179
3180 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
3181 ret = btrfs_rm_device(fs_info, NULL, vol_args->devid);
3182 } else {
3183 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
3184 ret = btrfs_rm_device(fs_info, vol_args->name, 0);
3185 }
3186 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3187
3188 if (!ret) {
3189 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
3190 btrfs_info(fs_info, "device deleted: id %llu",
3191 vol_args->devid);
3192 else
3193 btrfs_info(fs_info, "device deleted: %s",
3194 vol_args->name);
3195 }
3196out:
3197 kfree(vol_args);
3198err_drop:
3199 mnt_drop_write_file(file);
3200 return ret;
3201}
3202
3203static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
3204{
3205 struct inode *inode = file_inode(file);
3206 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3207 struct btrfs_ioctl_vol_args *vol_args;
3208 int ret;
3209
3210 if (!capable(CAP_SYS_ADMIN))
3211 return -EPERM;
3212
3213 ret = mnt_want_write_file(file);
3214 if (ret)
3215 return ret;
3216
3217 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
3218 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3219 goto out_drop_write;
3220 }
3221
3222 vol_args = memdup_user(arg, sizeof(*vol_args));
3223 if (IS_ERR(vol_args)) {
3224 ret = PTR_ERR(vol_args);
3225 goto out;
3226 }
3227
3228 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3229 ret = btrfs_rm_device(fs_info, vol_args->name, 0);
3230
3231 if (!ret)
3232 btrfs_info(fs_info, "disk deleted %s", vol_args->name);
3233 kfree(vol_args);
3234out:
3235 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3236out_drop_write:
3237 mnt_drop_write_file(file);
3238
3239 return ret;
3240}
3241
3242static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,
3243 void __user *arg)
3244{
3245 struct btrfs_ioctl_fs_info_args *fi_args;
3246 struct btrfs_device *device;
3247 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
3248 u64 flags_in;
3249 int ret = 0;
3250
3251 fi_args = memdup_user(arg, sizeof(*fi_args));
3252 if (IS_ERR(fi_args))
3253 return PTR_ERR(fi_args);
3254
3255 flags_in = fi_args->flags;
3256 memset(fi_args, 0, sizeof(*fi_args));
3257
3258 rcu_read_lock();
3259 fi_args->num_devices = fs_devices->num_devices;
3260
3261 list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
3262 if (device->devid > fi_args->max_id)
3263 fi_args->max_id = device->devid;
3264 }
3265 rcu_read_unlock();
3266
3267 memcpy(&fi_args->fsid, fs_devices->fsid, sizeof(fi_args->fsid));
3268 fi_args->nodesize = fs_info->nodesize;
3269 fi_args->sectorsize = fs_info->sectorsize;
3270 fi_args->clone_alignment = fs_info->sectorsize;
3271
3272 if (flags_in & BTRFS_FS_INFO_FLAG_CSUM_INFO) {
3273 fi_args->csum_type = btrfs_super_csum_type(fs_info->super_copy);
3274 fi_args->csum_size = btrfs_super_csum_size(fs_info->super_copy);
3275 fi_args->flags |= BTRFS_FS_INFO_FLAG_CSUM_INFO;
3276 }
3277
3278 if (flags_in & BTRFS_FS_INFO_FLAG_GENERATION) {
3279 fi_args->generation = fs_info->generation;
3280 fi_args->flags |= BTRFS_FS_INFO_FLAG_GENERATION;
3281 }
3282
3283 if (flags_in & BTRFS_FS_INFO_FLAG_METADATA_UUID) {
3284 memcpy(&fi_args->metadata_uuid, fs_devices->metadata_uuid,
3285 sizeof(fi_args->metadata_uuid));
3286 fi_args->flags |= BTRFS_FS_INFO_FLAG_METADATA_UUID;
3287 }
3288
3289 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
3290 ret = -EFAULT;
3291
3292 kfree(fi_args);
3293 return ret;
3294}
3295
3296static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,
3297 void __user *arg)
3298{
3299 struct btrfs_ioctl_dev_info_args *di_args;
3300 struct btrfs_device *dev;
3301 int ret = 0;
3302 char *s_uuid = NULL;
3303
3304 di_args = memdup_user(arg, sizeof(*di_args));
3305 if (IS_ERR(di_args))
3306 return PTR_ERR(di_args);
3307
3308 if (!btrfs_is_empty_uuid(di_args->uuid))
3309 s_uuid = di_args->uuid;
3310
3311 rcu_read_lock();
3312 dev = btrfs_find_device(fs_info->fs_devices, di_args->devid, s_uuid,
3313 NULL, true);
3314
3315 if (!dev) {
3316 ret = -ENODEV;
3317 goto out;
3318 }
3319
3320 di_args->devid = dev->devid;
3321 di_args->bytes_used = btrfs_device_get_bytes_used(dev);
3322 di_args->total_bytes = btrfs_device_get_total_bytes(dev);
3323 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
3324 if (dev->name) {
3325 strncpy(di_args->path, rcu_str_deref(dev->name),
3326 sizeof(di_args->path) - 1);
3327 di_args->path[sizeof(di_args->path) - 1] = 0;
3328 } else {
3329 di_args->path[0] = '\0';
3330 }
3331
3332out:
3333 rcu_read_unlock();
3334 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
3335 ret = -EFAULT;
3336
3337 kfree(di_args);
3338 return ret;
3339}
3340
3341static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3342{
3343 struct inode *inode = file_inode(file);
3344 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3345 struct btrfs_root *root = BTRFS_I(inode)->root;
3346 struct btrfs_root *new_root;
3347 struct btrfs_dir_item *di;
3348 struct btrfs_trans_handle *trans;
3349 struct btrfs_path *path = NULL;
3350 struct btrfs_disk_key disk_key;
3351 u64 objectid = 0;
3352 u64 dir_id;
3353 int ret;
3354
3355 if (!capable(CAP_SYS_ADMIN))
3356 return -EPERM;
3357
3358 ret = mnt_want_write_file(file);
3359 if (ret)
3360 return ret;
3361
3362 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3363 ret = -EFAULT;
3364 goto out;
3365 }
3366
3367 if (!objectid)
3368 objectid = BTRFS_FS_TREE_OBJECTID;
3369
3370 new_root = btrfs_get_fs_root(fs_info, objectid, true);
3371 if (IS_ERR(new_root)) {
3372 ret = PTR_ERR(new_root);
3373 goto out;
3374 }
3375 if (!is_fstree(new_root->root_key.objectid)) {
3376 ret = -ENOENT;
3377 goto out_free;
3378 }
3379
3380 path = btrfs_alloc_path();
3381 if (!path) {
3382 ret = -ENOMEM;
3383 goto out_free;
3384 }
3385 path->leave_spinning = 1;
3386
3387 trans = btrfs_start_transaction(root, 1);
3388 if (IS_ERR(trans)) {
3389 ret = PTR_ERR(trans);
3390 goto out_free;
3391 }
3392
3393 dir_id = btrfs_super_root_dir(fs_info->super_copy);
3394 di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
3395 dir_id, "default", 7, 1);
3396 if (IS_ERR_OR_NULL(di)) {
3397 btrfs_release_path(path);
3398 btrfs_end_transaction(trans);
3399 btrfs_err(fs_info,
3400 "Umm, you don't have the default diritem, this isn't going to work");
3401 ret = -ENOENT;
3402 goto out_free;
3403 }
3404
3405 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3406 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3407 btrfs_mark_buffer_dirty(path->nodes[0]);
3408 btrfs_release_path(path);
3409
3410 btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
3411 btrfs_end_transaction(trans);
3412out_free:
3413 btrfs_put_root(new_root);
3414 btrfs_free_path(path);
3415out:
3416 mnt_drop_write_file(file);
3417 return ret;
3418}
3419
3420static void get_block_group_info(struct list_head *groups_list,
3421 struct btrfs_ioctl_space_info *space)
3422{
3423 struct btrfs_block_group *block_group;
3424
3425 space->total_bytes = 0;
3426 space->used_bytes = 0;
3427 space->flags = 0;
3428 list_for_each_entry(block_group, groups_list, list) {
3429 space->flags = block_group->flags;
3430 space->total_bytes += block_group->length;
3431 space->used_bytes += block_group->used;
3432 }
3433}
3434
3435static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
3436 void __user *arg)
3437{
3438 struct btrfs_ioctl_space_args space_args;
3439 struct btrfs_ioctl_space_info space;
3440 struct btrfs_ioctl_space_info *dest;
3441 struct btrfs_ioctl_space_info *dest_orig;
3442 struct btrfs_ioctl_space_info __user *user_dest;
3443 struct btrfs_space_info *info;
3444 static const u64 types[] = {
3445 BTRFS_BLOCK_GROUP_DATA,
3446 BTRFS_BLOCK_GROUP_SYSTEM,
3447 BTRFS_BLOCK_GROUP_METADATA,
3448 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA
3449 };
3450 int num_types = 4;
3451 int alloc_size;
3452 int ret = 0;
3453 u64 slot_count = 0;
3454 int i, c;
3455
3456 if (copy_from_user(&space_args,
3457 (struct btrfs_ioctl_space_args __user *)arg,
3458 sizeof(space_args)))
3459 return -EFAULT;
3460
3461 for (i = 0; i < num_types; i++) {
3462 struct btrfs_space_info *tmp;
3463
3464 info = NULL;
3465 rcu_read_lock();
3466 list_for_each_entry_rcu(tmp, &fs_info->space_info,
3467 list) {
3468 if (tmp->flags == types[i]) {
3469 info = tmp;
3470 break;
3471 }
3472 }
3473 rcu_read_unlock();
3474
3475 if (!info)
3476 continue;
3477
3478 down_read(&info->groups_sem);
3479 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3480 if (!list_empty(&info->block_groups[c]))
3481 slot_count++;
3482 }
3483 up_read(&info->groups_sem);
3484 }
3485
3486 /*
3487 * Global block reserve, exported as a space_info
3488 */
3489 slot_count++;
3490
3491 /* space_slots == 0 means they are asking for a count */
3492 if (space_args.space_slots == 0) {
3493 space_args.total_spaces = slot_count;
3494 goto out;
3495 }
3496
3497 slot_count = min_t(u64, space_args.space_slots, slot_count);
3498
3499 alloc_size = sizeof(*dest) * slot_count;
3500
3501 /* we generally have at most 6 or so space infos, one for each raid
3502 * level. So, a whole page should be more than enough for everyone
3503 */
3504 if (alloc_size > PAGE_SIZE)
3505 return -ENOMEM;
3506
3507 space_args.total_spaces = 0;
3508 dest = kmalloc(alloc_size, GFP_KERNEL);
3509 if (!dest)
3510 return -ENOMEM;
3511 dest_orig = dest;
3512
3513 /* now we have a buffer to copy into */
3514 for (i = 0; i < num_types; i++) {
3515 struct btrfs_space_info *tmp;
3516
3517 if (!slot_count)
3518 break;
3519
3520 info = NULL;
3521 rcu_read_lock();
3522 list_for_each_entry_rcu(tmp, &fs_info->space_info,
3523 list) {
3524 if (tmp->flags == types[i]) {
3525 info = tmp;
3526 break;
3527 }
3528 }
3529 rcu_read_unlock();
3530
3531 if (!info)
3532 continue;
3533 down_read(&info->groups_sem);
3534 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3535 if (!list_empty(&info->block_groups[c])) {
3536 get_block_group_info(&info->block_groups[c],
3537 &space);
3538 memcpy(dest, &space, sizeof(space));
3539 dest++;
3540 space_args.total_spaces++;
3541 slot_count--;
3542 }
3543 if (!slot_count)
3544 break;
3545 }
3546 up_read(&info->groups_sem);
3547 }
3548
3549 /*
3550 * Add global block reserve
3551 */
3552 if (slot_count) {
3553 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3554
3555 spin_lock(&block_rsv->lock);
3556 space.total_bytes = block_rsv->size;
3557 space.used_bytes = block_rsv->size - block_rsv->reserved;
3558 spin_unlock(&block_rsv->lock);
3559 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
3560 memcpy(dest, &space, sizeof(space));
3561 space_args.total_spaces++;
3562 }
3563
3564 user_dest = (struct btrfs_ioctl_space_info __user *)
3565 (arg + sizeof(struct btrfs_ioctl_space_args));
3566
3567 if (copy_to_user(user_dest, dest_orig, alloc_size))
3568 ret = -EFAULT;
3569
3570 kfree(dest_orig);
3571out:
3572 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
3573 ret = -EFAULT;
3574
3575 return ret;
3576}
3577
3578static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
3579 void __user *argp)
3580{
3581 struct btrfs_trans_handle *trans;
3582 u64 transid;
3583 int ret;
3584
3585 trans = btrfs_attach_transaction_barrier(root);
3586 if (IS_ERR(trans)) {
3587 if (PTR_ERR(trans) != -ENOENT)
3588 return PTR_ERR(trans);
3589
3590 /* No running transaction, don't bother */
3591 transid = root->fs_info->last_trans_committed;
3592 goto out;
3593 }
3594 transid = trans->transid;
3595 ret = btrfs_commit_transaction_async(trans, 0);
3596 if (ret) {
3597 btrfs_end_transaction(trans);
3598 return ret;
3599 }
3600out:
3601 if (argp)
3602 if (copy_to_user(argp, &transid, sizeof(transid)))
3603 return -EFAULT;
3604 return 0;
3605}
3606
3607static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,
3608 void __user *argp)
3609{
3610 u64 transid;
3611
3612 if (argp) {
3613 if (copy_from_user(&transid, argp, sizeof(transid)))
3614 return -EFAULT;
3615 } else {
3616 transid = 0; /* current trans */
3617 }
3618 return btrfs_wait_for_commit(fs_info, transid);
3619}
3620
3621static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
3622{
3623 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
3624 struct btrfs_ioctl_scrub_args *sa;
3625 int ret;
3626
3627 if (!capable(CAP_SYS_ADMIN))
3628 return -EPERM;
3629
3630 sa = memdup_user(arg, sizeof(*sa));
3631 if (IS_ERR(sa))
3632 return PTR_ERR(sa);
3633
3634 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
3635 ret = mnt_want_write_file(file);
3636 if (ret)
3637 goto out;
3638 }
3639
3640 ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,
3641 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
3642 0);
3643
3644 /*
3645 * Copy scrub args to user space even if btrfs_scrub_dev() returned an
3646 * error. This is important as it allows user space to know how much
3647 * progress scrub has done. For example, if scrub is canceled we get
3648 * -ECANCELED from btrfs_scrub_dev() and return that error back to user
3649 * space. Later user space can inspect the progress from the structure
3650 * btrfs_ioctl_scrub_args and resume scrub from where it left off
3651 * previously (btrfs-progs does this).
3652 * If we fail to copy the btrfs_ioctl_scrub_args structure to user space
3653 * then return -EFAULT to signal the structure was not copied or it may
3654 * be corrupt and unreliable due to a partial copy.
3655 */
3656 if (copy_to_user(arg, sa, sizeof(*sa)))
3657 ret = -EFAULT;
3658
3659 if (!(sa->flags & BTRFS_SCRUB_READONLY))
3660 mnt_drop_write_file(file);
3661out:
3662 kfree(sa);
3663 return ret;
3664}
3665
3666static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)
3667{
3668 if (!capable(CAP_SYS_ADMIN))
3669 return -EPERM;
3670
3671 return btrfs_scrub_cancel(fs_info);
3672}
3673
3674static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
3675 void __user *arg)
3676{
3677 struct btrfs_ioctl_scrub_args *sa;
3678 int ret;
3679
3680 if (!capable(CAP_SYS_ADMIN))
3681 return -EPERM;
3682
3683 sa = memdup_user(arg, sizeof(*sa));
3684 if (IS_ERR(sa))
3685 return PTR_ERR(sa);
3686
3687 ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
3688
3689 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
3690 ret = -EFAULT;
3691
3692 kfree(sa);
3693 return ret;
3694}
3695
3696static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
3697 void __user *arg)
3698{
3699 struct btrfs_ioctl_get_dev_stats *sa;
3700 int ret;
3701
3702 sa = memdup_user(arg, sizeof(*sa));
3703 if (IS_ERR(sa))
3704 return PTR_ERR(sa);
3705
3706 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3707 kfree(sa);
3708 return -EPERM;
3709 }
3710
3711 ret = btrfs_get_dev_stats(fs_info, sa);
3712
3713 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
3714 ret = -EFAULT;
3715
3716 kfree(sa);
3717 return ret;
3718}
3719
3720static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
3721 void __user *arg)
3722{
3723 struct btrfs_ioctl_dev_replace_args *p;
3724 int ret;
3725
3726 if (!capable(CAP_SYS_ADMIN))
3727 return -EPERM;
3728
3729 p = memdup_user(arg, sizeof(*p));
3730 if (IS_ERR(p))
3731 return PTR_ERR(p);
3732
3733 switch (p->cmd) {
3734 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3735 if (sb_rdonly(fs_info->sb)) {
3736 ret = -EROFS;
3737 goto out;
3738 }
3739 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
3740 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3741 } else {
3742 ret = btrfs_dev_replace_by_ioctl(fs_info, p);
3743 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3744 }
3745 break;
3746 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
3747 btrfs_dev_replace_status(fs_info, p);
3748 ret = 0;
3749 break;
3750 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
3751 p->result = btrfs_dev_replace_cancel(fs_info);
3752 ret = 0;
3753 break;
3754 default:
3755 ret = -EINVAL;
3756 break;
3757 }
3758
3759 if ((ret == 0 || ret == -ECANCELED) && copy_to_user(arg, p, sizeof(*p)))
3760 ret = -EFAULT;
3761out:
3762 kfree(p);
3763 return ret;
3764}
3765
3766static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3767{
3768 int ret = 0;
3769 int i;
3770 u64 rel_ptr;
3771 int size;
3772 struct btrfs_ioctl_ino_path_args *ipa = NULL;
3773 struct inode_fs_paths *ipath = NULL;
3774 struct btrfs_path *path;
3775
3776 if (!capable(CAP_DAC_READ_SEARCH))
3777 return -EPERM;
3778
3779 path = btrfs_alloc_path();
3780 if (!path) {
3781 ret = -ENOMEM;
3782 goto out;
3783 }
3784
3785 ipa = memdup_user(arg, sizeof(*ipa));
3786 if (IS_ERR(ipa)) {
3787 ret = PTR_ERR(ipa);
3788 ipa = NULL;
3789 goto out;
3790 }
3791
3792 size = min_t(u32, ipa->size, 4096);
3793 ipath = init_ipath(size, root, path);
3794 if (IS_ERR(ipath)) {
3795 ret = PTR_ERR(ipath);
3796 ipath = NULL;
3797 goto out;
3798 }
3799
3800 ret = paths_from_inode(ipa->inum, ipath);
3801 if (ret < 0)
3802 goto out;
3803
3804 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3805 rel_ptr = ipath->fspath->val[i] -
3806 (u64)(unsigned long)ipath->fspath->val;
3807 ipath->fspath->val[i] = rel_ptr;
3808 }
3809
3810 ret = copy_to_user((void __user *)(unsigned long)ipa->fspath,
3811 ipath->fspath, size);
3812 if (ret) {
3813 ret = -EFAULT;
3814 goto out;
3815 }
3816
3817out:
3818 btrfs_free_path(path);
3819 free_ipath(ipath);
3820 kfree(ipa);
3821
3822 return ret;
3823}
3824
3825static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3826{
3827 struct btrfs_data_container *inodes = ctx;
3828 const size_t c = 3 * sizeof(u64);
3829
3830 if (inodes->bytes_left >= c) {
3831 inodes->bytes_left -= c;
3832 inodes->val[inodes->elem_cnt] = inum;
3833 inodes->val[inodes->elem_cnt + 1] = offset;
3834 inodes->val[inodes->elem_cnt + 2] = root;
3835 inodes->elem_cnt += 3;
3836 } else {
3837 inodes->bytes_missing += c - inodes->bytes_left;
3838 inodes->bytes_left = 0;
3839 inodes->elem_missed += 3;
3840 }
3841
3842 return 0;
3843}
3844
3845static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,
3846 void __user *arg, int version)
3847{
3848 int ret = 0;
3849 int size;
3850 struct btrfs_ioctl_logical_ino_args *loi;
3851 struct btrfs_data_container *inodes = NULL;
3852 struct btrfs_path *path = NULL;
3853 bool ignore_offset;
3854
3855 if (!capable(CAP_SYS_ADMIN))
3856 return -EPERM;
3857
3858 loi = memdup_user(arg, sizeof(*loi));
3859 if (IS_ERR(loi))
3860 return PTR_ERR(loi);
3861
3862 if (version == 1) {
3863 ignore_offset = false;
3864 size = min_t(u32, loi->size, SZ_64K);
3865 } else {
3866 /* All reserved bits must be 0 for now */
3867 if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) {
3868 ret = -EINVAL;
3869 goto out_loi;
3870 }
3871 /* Only accept flags we have defined so far */
3872 if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) {
3873 ret = -EINVAL;
3874 goto out_loi;
3875 }
3876 ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET;
3877 size = min_t(u32, loi->size, SZ_16M);
3878 }
3879
3880 path = btrfs_alloc_path();
3881 if (!path) {
3882 ret = -ENOMEM;
3883 goto out;
3884 }
3885
3886 inodes = init_data_container(size);
3887 if (IS_ERR(inodes)) {
3888 ret = PTR_ERR(inodes);
3889 inodes = NULL;
3890 goto out;
3891 }
3892
3893 ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
3894 build_ino_list, inodes, ignore_offset);
3895 if (ret == -EINVAL)
3896 ret = -ENOENT;
3897 if (ret < 0)
3898 goto out;
3899
3900 ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes,
3901 size);
3902 if (ret)
3903 ret = -EFAULT;
3904
3905out:
3906 btrfs_free_path(path);
3907 kvfree(inodes);
3908out_loi:
3909 kfree(loi);
3910
3911 return ret;
3912}
3913
3914void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info,
3915 struct btrfs_ioctl_balance_args *bargs)
3916{
3917 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3918
3919 bargs->flags = bctl->flags;
3920
3921 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags))
3922 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3923 if (atomic_read(&fs_info->balance_pause_req))
3924 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3925 if (atomic_read(&fs_info->balance_cancel_req))
3926 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3927
3928 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3929 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3930 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3931
3932 spin_lock(&fs_info->balance_lock);
3933 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3934 spin_unlock(&fs_info->balance_lock);
3935}
3936
3937static long btrfs_ioctl_balance(struct file *file, void __user *arg)
3938{
3939 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3940 struct btrfs_fs_info *fs_info = root->fs_info;
3941 struct btrfs_ioctl_balance_args *bargs;
3942 struct btrfs_balance_control *bctl;
3943 bool need_unlock; /* for mut. excl. ops lock */
3944 int ret;
3945
3946 if (!capable(CAP_SYS_ADMIN))
3947 return -EPERM;
3948
3949 ret = mnt_want_write_file(file);
3950 if (ret)
3951 return ret;
3952
3953again:
3954 if (!test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
3955 mutex_lock(&fs_info->balance_mutex);
3956 need_unlock = true;
3957 goto locked;
3958 }
3959
3960 /*
3961 * mut. excl. ops lock is locked. Three possibilities:
3962 * (1) some other op is running
3963 * (2) balance is running
3964 * (3) balance is paused -- special case (think resume)
3965 */
3966 mutex_lock(&fs_info->balance_mutex);
3967 if (fs_info->balance_ctl) {
3968 /* this is either (2) or (3) */
3969 if (!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
3970 mutex_unlock(&fs_info->balance_mutex);
3971 /*
3972 * Lock released to allow other waiters to continue,
3973 * we'll reexamine the status again.
3974 */
3975 mutex_lock(&fs_info->balance_mutex);
3976
3977 if (fs_info->balance_ctl &&
3978 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
3979 /* this is (3) */
3980 need_unlock = false;
3981 goto locked;
3982 }
3983
3984 mutex_unlock(&fs_info->balance_mutex);
3985 goto again;
3986 } else {
3987 /* this is (2) */
3988 mutex_unlock(&fs_info->balance_mutex);
3989 ret = -EINPROGRESS;
3990 goto out;
3991 }
3992 } else {
3993 /* this is (1) */
3994 mutex_unlock(&fs_info->balance_mutex);
3995 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3996 goto out;
3997 }
3998
3999locked:
4000 BUG_ON(!test_bit(BTRFS_FS_EXCL_OP, &fs_info->flags));
4001
4002 if (arg) {
4003 bargs = memdup_user(arg, sizeof(*bargs));
4004 if (IS_ERR(bargs)) {
4005 ret = PTR_ERR(bargs);
4006 goto out_unlock;
4007 }
4008
4009 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4010 if (!fs_info->balance_ctl) {
4011 ret = -ENOTCONN;
4012 goto out_bargs;
4013 }
4014
4015 bctl = fs_info->balance_ctl;
4016 spin_lock(&fs_info->balance_lock);
4017 bctl->flags |= BTRFS_BALANCE_RESUME;
4018 spin_unlock(&fs_info->balance_lock);
4019
4020 goto do_balance;
4021 }
4022 } else {
4023 bargs = NULL;
4024 }
4025
4026 if (fs_info->balance_ctl) {
4027 ret = -EINPROGRESS;
4028 goto out_bargs;
4029 }
4030
4031 bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
4032 if (!bctl) {
4033 ret = -ENOMEM;
4034 goto out_bargs;
4035 }
4036
4037 if (arg) {
4038 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4039 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4040 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4041
4042 bctl->flags = bargs->flags;
4043 } else {
4044 /* balance everything - no filters */
4045 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4046 }
4047
4048 if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
4049 ret = -EINVAL;
4050 goto out_bctl;
4051 }
4052
4053do_balance:
4054 /*
4055 * Ownership of bctl and filesystem flag BTRFS_FS_EXCL_OP goes to
4056 * btrfs_balance. bctl is freed in reset_balance_state, or, if
4057 * restriper was paused all the way until unmount, in free_fs_info.
4058 * The flag should be cleared after reset_balance_state.
4059 */
4060 need_unlock = false;
4061
4062 ret = btrfs_balance(fs_info, bctl, bargs);
4063 bctl = NULL;
4064
4065 if ((ret == 0 || ret == -ECANCELED) && arg) {
4066 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4067 ret = -EFAULT;
4068 }
4069
4070out_bctl:
4071 kfree(bctl);
4072out_bargs:
4073 kfree(bargs);
4074out_unlock:
4075 mutex_unlock(&fs_info->balance_mutex);
4076 if (need_unlock)
4077 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
4078out:
4079 mnt_drop_write_file(file);
4080 return ret;
4081}
4082
4083static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
4084{
4085 if (!capable(CAP_SYS_ADMIN))
4086 return -EPERM;
4087
4088 switch (cmd) {
4089 case BTRFS_BALANCE_CTL_PAUSE:
4090 return btrfs_pause_balance(fs_info);
4091 case BTRFS_BALANCE_CTL_CANCEL:
4092 return btrfs_cancel_balance(fs_info);
4093 }
4094
4095 return -EINVAL;
4096}
4097
4098static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
4099 void __user *arg)
4100{
4101 struct btrfs_ioctl_balance_args *bargs;
4102 int ret = 0;
4103
4104 if (!capable(CAP_SYS_ADMIN))
4105 return -EPERM;
4106
4107 mutex_lock(&fs_info->balance_mutex);
4108 if (!fs_info->balance_ctl) {
4109 ret = -ENOTCONN;
4110 goto out;
4111 }
4112
4113 bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
4114 if (!bargs) {
4115 ret = -ENOMEM;
4116 goto out;
4117 }
4118
4119 btrfs_update_ioctl_balance_args(fs_info, bargs);
4120
4121 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4122 ret = -EFAULT;
4123
4124 kfree(bargs);
4125out:
4126 mutex_unlock(&fs_info->balance_mutex);
4127 return ret;
4128}
4129
4130static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4131{
4132 struct inode *inode = file_inode(file);
4133 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4134 struct btrfs_ioctl_quota_ctl_args *sa;
4135 int ret;
4136
4137 if (!capable(CAP_SYS_ADMIN))
4138 return -EPERM;
4139
4140 ret = mnt_want_write_file(file);
4141 if (ret)
4142 return ret;
4143
4144 sa = memdup_user(arg, sizeof(*sa));
4145 if (IS_ERR(sa)) {
4146 ret = PTR_ERR(sa);
4147 goto drop_write;
4148 }
4149
4150 down_write(&fs_info->subvol_sem);
4151
4152 switch (sa->cmd) {
4153 case BTRFS_QUOTA_CTL_ENABLE:
4154 ret = btrfs_quota_enable(fs_info);
4155 break;
4156 case BTRFS_QUOTA_CTL_DISABLE:
4157 ret = btrfs_quota_disable(fs_info);
4158 break;
4159 default:
4160 ret = -EINVAL;
4161 break;
4162 }
4163
4164 kfree(sa);
4165 up_write(&fs_info->subvol_sem);
4166drop_write:
4167 mnt_drop_write_file(file);
4168 return ret;
4169}
4170
4171static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4172{
4173 struct inode *inode = file_inode(file);
4174 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4175 struct btrfs_root *root = BTRFS_I(inode)->root;
4176 struct btrfs_ioctl_qgroup_assign_args *sa;
4177 struct btrfs_trans_handle *trans;
4178 int ret;
4179 int err;
4180
4181 if (!capable(CAP_SYS_ADMIN))
4182 return -EPERM;
4183
4184 ret = mnt_want_write_file(file);
4185 if (ret)
4186 return ret;
4187
4188 sa = memdup_user(arg, sizeof(*sa));
4189 if (IS_ERR(sa)) {
4190 ret = PTR_ERR(sa);
4191 goto drop_write;
4192 }
4193
4194 trans = btrfs_join_transaction(root);
4195 if (IS_ERR(trans)) {
4196 ret = PTR_ERR(trans);
4197 goto out;
4198 }
4199
4200 if (sa->assign) {
4201 ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst);
4202 } else {
4203 ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst);
4204 }
4205
4206 /* update qgroup status and info */
4207 err = btrfs_run_qgroups(trans);
4208 if (err < 0)
4209 btrfs_handle_fs_error(fs_info, err,
4210 "failed to update qgroup status and info");
4211 err = btrfs_end_transaction(trans);
4212 if (err && !ret)
4213 ret = err;
4214
4215out:
4216 kfree(sa);
4217drop_write:
4218 mnt_drop_write_file(file);
4219 return ret;
4220}
4221
4222static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4223{
4224 struct inode *inode = file_inode(file);
4225 struct btrfs_root *root = BTRFS_I(inode)->root;
4226 struct btrfs_ioctl_qgroup_create_args *sa;
4227 struct btrfs_trans_handle *trans;
4228 int ret;
4229 int err;
4230
4231 if (!capable(CAP_SYS_ADMIN))
4232 return -EPERM;
4233
4234 ret = mnt_want_write_file(file);
4235 if (ret)
4236 return ret;
4237
4238 sa = memdup_user(arg, sizeof(*sa));
4239 if (IS_ERR(sa)) {
4240 ret = PTR_ERR(sa);
4241 goto drop_write;
4242 }
4243
4244 if (!sa->qgroupid) {
4245 ret = -EINVAL;
4246 goto out;
4247 }
4248
4249 trans = btrfs_join_transaction(root);
4250 if (IS_ERR(trans)) {
4251 ret = PTR_ERR(trans);
4252 goto out;
4253 }
4254
4255 if (sa->create) {
4256 ret = btrfs_create_qgroup(trans, sa->qgroupid);
4257 } else {
4258 ret = btrfs_remove_qgroup(trans, sa->qgroupid);
4259 }
4260
4261 err = btrfs_end_transaction(trans);
4262 if (err && !ret)
4263 ret = err;
4264
4265out:
4266 kfree(sa);
4267drop_write:
4268 mnt_drop_write_file(file);
4269 return ret;
4270}
4271
4272static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4273{
4274 struct inode *inode = file_inode(file);
4275 struct btrfs_root *root = BTRFS_I(inode)->root;
4276 struct btrfs_ioctl_qgroup_limit_args *sa;
4277 struct btrfs_trans_handle *trans;
4278 int ret;
4279 int err;
4280 u64 qgroupid;
4281
4282 if (!capable(CAP_SYS_ADMIN))
4283 return -EPERM;
4284
4285 ret = mnt_want_write_file(file);
4286 if (ret)
4287 return ret;
4288
4289 sa = memdup_user(arg, sizeof(*sa));
4290 if (IS_ERR(sa)) {
4291 ret = PTR_ERR(sa);
4292 goto drop_write;
4293 }
4294
4295 trans = btrfs_join_transaction(root);
4296 if (IS_ERR(trans)) {
4297 ret = PTR_ERR(trans);
4298 goto out;
4299 }
4300
4301 qgroupid = sa->qgroupid;
4302 if (!qgroupid) {
4303 /* take the current subvol as qgroup */
4304 qgroupid = root->root_key.objectid;
4305 }
4306
4307 ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim);
4308
4309 err = btrfs_end_transaction(trans);
4310 if (err && !ret)
4311 ret = err;
4312
4313out:
4314 kfree(sa);
4315drop_write:
4316 mnt_drop_write_file(file);
4317 return ret;
4318}
4319
4320static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4321{
4322 struct inode *inode = file_inode(file);
4323 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4324 struct btrfs_ioctl_quota_rescan_args *qsa;
4325 int ret;
4326
4327 if (!capable(CAP_SYS_ADMIN))
4328 return -EPERM;
4329
4330 ret = mnt_want_write_file(file);
4331 if (ret)
4332 return ret;
4333
4334 qsa = memdup_user(arg, sizeof(*qsa));
4335 if (IS_ERR(qsa)) {
4336 ret = PTR_ERR(qsa);
4337 goto drop_write;
4338 }
4339
4340 if (qsa->flags) {
4341 ret = -EINVAL;
4342 goto out;
4343 }
4344
4345 ret = btrfs_qgroup_rescan(fs_info);
4346
4347out:
4348 kfree(qsa);
4349drop_write:
4350 mnt_drop_write_file(file);
4351 return ret;
4352}
4353
4354static long btrfs_ioctl_quota_rescan_status(struct btrfs_fs_info *fs_info,
4355 void __user *arg)
4356{
4357 struct btrfs_ioctl_quota_rescan_args *qsa;
4358 int ret = 0;
4359
4360 if (!capable(CAP_SYS_ADMIN))
4361 return -EPERM;
4362
4363 qsa = kzalloc(sizeof(*qsa), GFP_KERNEL);
4364 if (!qsa)
4365 return -ENOMEM;
4366
4367 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4368 qsa->flags = 1;
4369 qsa->progress = fs_info->qgroup_rescan_progress.objectid;
4370 }
4371
4372 if (copy_to_user(arg, qsa, sizeof(*qsa)))
4373 ret = -EFAULT;
4374
4375 kfree(qsa);
4376 return ret;
4377}
4378
4379static long btrfs_ioctl_quota_rescan_wait(struct btrfs_fs_info *fs_info,
4380 void __user *arg)
4381{
4382 if (!capable(CAP_SYS_ADMIN))
4383 return -EPERM;
4384
4385 return btrfs_qgroup_wait_for_completion(fs_info, true);
4386}
4387
4388static long _btrfs_ioctl_set_received_subvol(struct file *file,
4389 struct btrfs_ioctl_received_subvol_args *sa)
4390{
4391 struct inode *inode = file_inode(file);
4392 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4393 struct btrfs_root *root = BTRFS_I(inode)->root;
4394 struct btrfs_root_item *root_item = &root->root_item;
4395 struct btrfs_trans_handle *trans;
4396 struct timespec64 ct = current_time(inode);
4397 int ret = 0;
4398 int received_uuid_changed;
4399
4400 if (!inode_owner_or_capable(inode))
4401 return -EPERM;
4402
4403 ret = mnt_want_write_file(file);
4404 if (ret < 0)
4405 return ret;
4406
4407 down_write(&fs_info->subvol_sem);
4408
4409 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
4410 ret = -EINVAL;
4411 goto out;
4412 }
4413
4414 if (btrfs_root_readonly(root)) {
4415 ret = -EROFS;
4416 goto out;
4417 }
4418
4419 /*
4420 * 1 - root item
4421 * 2 - uuid items (received uuid + subvol uuid)
4422 */
4423 trans = btrfs_start_transaction(root, 3);
4424 if (IS_ERR(trans)) {
4425 ret = PTR_ERR(trans);
4426 trans = NULL;
4427 goto out;
4428 }
4429
4430 sa->rtransid = trans->transid;
4431 sa->rtime.sec = ct.tv_sec;
4432 sa->rtime.nsec = ct.tv_nsec;
4433
4434 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4435 BTRFS_UUID_SIZE);
4436 if (received_uuid_changed &&
4437 !btrfs_is_empty_uuid(root_item->received_uuid)) {
4438 ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid,
4439 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4440 root->root_key.objectid);
4441 if (ret && ret != -ENOENT) {
4442 btrfs_abort_transaction(trans, ret);
4443 btrfs_end_transaction(trans);
4444 goto out;
4445 }
4446 }
4447 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4448 btrfs_set_root_stransid(root_item, sa->stransid);
4449 btrfs_set_root_rtransid(root_item, sa->rtransid);
4450 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4451 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4452 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4453 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4454
4455 ret = btrfs_update_root(trans, fs_info->tree_root,
4456 &root->root_key, &root->root_item);
4457 if (ret < 0) {
4458 btrfs_end_transaction(trans);
4459 goto out;
4460 }
4461 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4462 ret = btrfs_uuid_tree_add(trans, sa->uuid,
4463 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4464 root->root_key.objectid);
4465 if (ret < 0 && ret != -EEXIST) {
4466 btrfs_abort_transaction(trans, ret);
4467 btrfs_end_transaction(trans);
4468 goto out;
4469 }
4470 }
4471 ret = btrfs_commit_transaction(trans);
4472out:
4473 up_write(&fs_info->subvol_sem);
4474 mnt_drop_write_file(file);
4475 return ret;
4476}
4477
4478#ifdef CONFIG_64BIT
4479static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4480 void __user *arg)
4481{
4482 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4483 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4484 int ret = 0;
4485
4486 args32 = memdup_user(arg, sizeof(*args32));
4487 if (IS_ERR(args32))
4488 return PTR_ERR(args32);
4489
4490 args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
4491 if (!args64) {
4492 ret = -ENOMEM;
4493 goto out;
4494 }
4495
4496 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4497 args64->stransid = args32->stransid;
4498 args64->rtransid = args32->rtransid;
4499 args64->stime.sec = args32->stime.sec;
4500 args64->stime.nsec = args32->stime.nsec;
4501 args64->rtime.sec = args32->rtime.sec;
4502 args64->rtime.nsec = args32->rtime.nsec;
4503 args64->flags = args32->flags;
4504
4505 ret = _btrfs_ioctl_set_received_subvol(file, args64);
4506 if (ret)
4507 goto out;
4508
4509 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4510 args32->stransid = args64->stransid;
4511 args32->rtransid = args64->rtransid;
4512 args32->stime.sec = args64->stime.sec;
4513 args32->stime.nsec = args64->stime.nsec;
4514 args32->rtime.sec = args64->rtime.sec;
4515 args32->rtime.nsec = args64->rtime.nsec;
4516 args32->flags = args64->flags;
4517
4518 ret = copy_to_user(arg, args32, sizeof(*args32));
4519 if (ret)
4520 ret = -EFAULT;
4521
4522out:
4523 kfree(args32);
4524 kfree(args64);
4525 return ret;
4526}
4527#endif
4528
4529static long btrfs_ioctl_set_received_subvol(struct file *file,
4530 void __user *arg)
4531{
4532 struct btrfs_ioctl_received_subvol_args *sa = NULL;
4533 int ret = 0;
4534
4535 sa = memdup_user(arg, sizeof(*sa));
4536 if (IS_ERR(sa))
4537 return PTR_ERR(sa);
4538
4539 ret = _btrfs_ioctl_set_received_subvol(file, sa);
4540
4541 if (ret)
4542 goto out;
4543
4544 ret = copy_to_user(arg, sa, sizeof(*sa));
4545 if (ret)
4546 ret = -EFAULT;
4547
4548out:
4549 kfree(sa);
4550 return ret;
4551}
4552
4553static int btrfs_ioctl_get_fslabel(struct btrfs_fs_info *fs_info,
4554 void __user *arg)
4555{
4556 size_t len;
4557 int ret;
4558 char label[BTRFS_LABEL_SIZE];
4559
4560 spin_lock(&fs_info->super_lock);
4561 memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
4562 spin_unlock(&fs_info->super_lock);
4563
4564 len = strnlen(label, BTRFS_LABEL_SIZE);
4565
4566 if (len == BTRFS_LABEL_SIZE) {
4567 btrfs_warn(fs_info,
4568 "label is too long, return the first %zu bytes",
4569 --len);
4570 }
4571
4572 ret = copy_to_user(arg, label, len);
4573
4574 return ret ? -EFAULT : 0;
4575}
4576
4577static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
4578{
4579 struct inode *inode = file_inode(file);
4580 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4581 struct btrfs_root *root = BTRFS_I(inode)->root;
4582 struct btrfs_super_block *super_block = fs_info->super_copy;
4583 struct btrfs_trans_handle *trans;
4584 char label[BTRFS_LABEL_SIZE];
4585 int ret;
4586
4587 if (!capable(CAP_SYS_ADMIN))
4588 return -EPERM;
4589
4590 if (copy_from_user(label, arg, sizeof(label)))
4591 return -EFAULT;
4592
4593 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
4594 btrfs_err(fs_info,
4595 "unable to set label with more than %d bytes",
4596 BTRFS_LABEL_SIZE - 1);
4597 return -EINVAL;
4598 }
4599
4600 ret = mnt_want_write_file(file);
4601 if (ret)
4602 return ret;
4603
4604 trans = btrfs_start_transaction(root, 0);
4605 if (IS_ERR(trans)) {
4606 ret = PTR_ERR(trans);
4607 goto out_unlock;
4608 }
4609
4610 spin_lock(&fs_info->super_lock);
4611 strcpy(super_block->label, label);
4612 spin_unlock(&fs_info->super_lock);
4613 ret = btrfs_commit_transaction(trans);
4614
4615out_unlock:
4616 mnt_drop_write_file(file);
4617 return ret;
4618}
4619
4620#define INIT_FEATURE_FLAGS(suffix) \
4621 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
4622 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
4623 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
4624
4625int btrfs_ioctl_get_supported_features(void __user *arg)
4626{
4627 static const struct btrfs_ioctl_feature_flags features[3] = {
4628 INIT_FEATURE_FLAGS(SUPP),
4629 INIT_FEATURE_FLAGS(SAFE_SET),
4630 INIT_FEATURE_FLAGS(SAFE_CLEAR)
4631 };
4632
4633 if (copy_to_user(arg, &features, sizeof(features)))
4634 return -EFAULT;
4635
4636 return 0;
4637}
4638
4639static int btrfs_ioctl_get_features(struct btrfs_fs_info *fs_info,
4640 void __user *arg)
4641{
4642 struct btrfs_super_block *super_block = fs_info->super_copy;
4643 struct btrfs_ioctl_feature_flags features;
4644
4645 features.compat_flags = btrfs_super_compat_flags(super_block);
4646 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
4647 features.incompat_flags = btrfs_super_incompat_flags(super_block);
4648
4649 if (copy_to_user(arg, &features, sizeof(features)))
4650 return -EFAULT;
4651
4652 return 0;
4653}
4654
4655static int check_feature_bits(struct btrfs_fs_info *fs_info,
4656 enum btrfs_feature_set set,
4657 u64 change_mask, u64 flags, u64 supported_flags,
4658 u64 safe_set, u64 safe_clear)
4659{
4660 const char *type = btrfs_feature_set_name(set);
4661 char *names;
4662 u64 disallowed, unsupported;
4663 u64 set_mask = flags & change_mask;
4664 u64 clear_mask = ~flags & change_mask;
4665
4666 unsupported = set_mask & ~supported_flags;
4667 if (unsupported) {
4668 names = btrfs_printable_features(set, unsupported);
4669 if (names) {
4670 btrfs_warn(fs_info,
4671 "this kernel does not support the %s feature bit%s",
4672 names, strchr(names, ',') ? "s" : "");
4673 kfree(names);
4674 } else
4675 btrfs_warn(fs_info,
4676 "this kernel does not support %s bits 0x%llx",
4677 type, unsupported);
4678 return -EOPNOTSUPP;
4679 }
4680
4681 disallowed = set_mask & ~safe_set;
4682 if (disallowed) {
4683 names = btrfs_printable_features(set, disallowed);
4684 if (names) {
4685 btrfs_warn(fs_info,
4686 "can't set the %s feature bit%s while mounted",
4687 names, strchr(names, ',') ? "s" : "");
4688 kfree(names);
4689 } else
4690 btrfs_warn(fs_info,
4691 "can't set %s bits 0x%llx while mounted",
4692 type, disallowed);
4693 return -EPERM;
4694 }
4695
4696 disallowed = clear_mask & ~safe_clear;
4697 if (disallowed) {
4698 names = btrfs_printable_features(set, disallowed);
4699 if (names) {
4700 btrfs_warn(fs_info,
4701 "can't clear the %s feature bit%s while mounted",
4702 names, strchr(names, ',') ? "s" : "");
4703 kfree(names);
4704 } else
4705 btrfs_warn(fs_info,
4706 "can't clear %s bits 0x%llx while mounted",
4707 type, disallowed);
4708 return -EPERM;
4709 }
4710
4711 return 0;
4712}
4713
4714#define check_feature(fs_info, change_mask, flags, mask_base) \
4715check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags, \
4716 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
4717 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
4718 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
4719
4720static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
4721{
4722 struct inode *inode = file_inode(file);
4723 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4724 struct btrfs_root *root = BTRFS_I(inode)->root;
4725 struct btrfs_super_block *super_block = fs_info->super_copy;
4726 struct btrfs_ioctl_feature_flags flags[2];
4727 struct btrfs_trans_handle *trans;
4728 u64 newflags;
4729 int ret;
4730
4731 if (!capable(CAP_SYS_ADMIN))
4732 return -EPERM;
4733
4734 if (copy_from_user(flags, arg, sizeof(flags)))
4735 return -EFAULT;
4736
4737 /* Nothing to do */
4738 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
4739 !flags[0].incompat_flags)
4740 return 0;
4741
4742 ret = check_feature(fs_info, flags[0].compat_flags,
4743 flags[1].compat_flags, COMPAT);
4744 if (ret)
4745 return ret;
4746
4747 ret = check_feature(fs_info, flags[0].compat_ro_flags,
4748 flags[1].compat_ro_flags, COMPAT_RO);
4749 if (ret)
4750 return ret;
4751
4752 ret = check_feature(fs_info, flags[0].incompat_flags,
4753 flags[1].incompat_flags, INCOMPAT);
4754 if (ret)
4755 return ret;
4756
4757 ret = mnt_want_write_file(file);
4758 if (ret)
4759 return ret;
4760
4761 trans = btrfs_start_transaction(root, 0);
4762 if (IS_ERR(trans)) {
4763 ret = PTR_ERR(trans);
4764 goto out_drop_write;
4765 }
4766
4767 spin_lock(&fs_info->super_lock);
4768 newflags = btrfs_super_compat_flags(super_block);
4769 newflags |= flags[0].compat_flags & flags[1].compat_flags;
4770 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
4771 btrfs_set_super_compat_flags(super_block, newflags);
4772
4773 newflags = btrfs_super_compat_ro_flags(super_block);
4774 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
4775 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
4776 btrfs_set_super_compat_ro_flags(super_block, newflags);
4777
4778 newflags = btrfs_super_incompat_flags(super_block);
4779 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
4780 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
4781 btrfs_set_super_incompat_flags(super_block, newflags);
4782 spin_unlock(&fs_info->super_lock);
4783
4784 ret = btrfs_commit_transaction(trans);
4785out_drop_write:
4786 mnt_drop_write_file(file);
4787
4788 return ret;
4789}
4790
4791static int _btrfs_ioctl_send(struct file *file, void __user *argp, bool compat)
4792{
4793 struct btrfs_ioctl_send_args *arg;
4794 int ret;
4795
4796 if (compat) {
4797#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4798 struct btrfs_ioctl_send_args_32 args32;
4799
4800 ret = copy_from_user(&args32, argp, sizeof(args32));
4801 if (ret)
4802 return -EFAULT;
4803 arg = kzalloc(sizeof(*arg), GFP_KERNEL);
4804 if (!arg)
4805 return -ENOMEM;
4806 arg->send_fd = args32.send_fd;
4807 arg->clone_sources_count = args32.clone_sources_count;
4808 arg->clone_sources = compat_ptr(args32.clone_sources);
4809 arg->parent_root = args32.parent_root;
4810 arg->flags = args32.flags;
4811 memcpy(arg->reserved, args32.reserved,
4812 sizeof(args32.reserved));
4813#else
4814 return -ENOTTY;
4815#endif
4816 } else {
4817 arg = memdup_user(argp, sizeof(*arg));
4818 if (IS_ERR(arg))
4819 return PTR_ERR(arg);
4820 }
4821 ret = btrfs_ioctl_send(file, arg);
4822 kfree(arg);
4823 return ret;
4824}
4825
4826long btrfs_ioctl(struct file *file, unsigned int
4827 cmd, unsigned long arg)
4828{
4829 struct inode *inode = file_inode(file);
4830 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4831 struct btrfs_root *root = BTRFS_I(inode)->root;
4832 void __user *argp = (void __user *)arg;
4833
4834 switch (cmd) {
4835 case FS_IOC_GETFLAGS:
4836 return btrfs_ioctl_getflags(file, argp);
4837 case FS_IOC_SETFLAGS:
4838 return btrfs_ioctl_setflags(file, argp);
4839 case FS_IOC_GETVERSION:
4840 return btrfs_ioctl_getversion(file, argp);
4841 case FS_IOC_GETFSLABEL:
4842 return btrfs_ioctl_get_fslabel(fs_info, argp);
4843 case FS_IOC_SETFSLABEL:
4844 return btrfs_ioctl_set_fslabel(file, argp);
4845 case FITRIM:
4846 return btrfs_ioctl_fitrim(fs_info, argp);
4847 case BTRFS_IOC_SNAP_CREATE:
4848 return btrfs_ioctl_snap_create(file, argp, 0);
4849 case BTRFS_IOC_SNAP_CREATE_V2:
4850 return btrfs_ioctl_snap_create_v2(file, argp, 0);
4851 case BTRFS_IOC_SUBVOL_CREATE:
4852 return btrfs_ioctl_snap_create(file, argp, 1);
4853 case BTRFS_IOC_SUBVOL_CREATE_V2:
4854 return btrfs_ioctl_snap_create_v2(file, argp, 1);
4855 case BTRFS_IOC_SNAP_DESTROY:
4856 return btrfs_ioctl_snap_destroy(file, argp, false);
4857 case BTRFS_IOC_SNAP_DESTROY_V2:
4858 return btrfs_ioctl_snap_destroy(file, argp, true);
4859 case BTRFS_IOC_SUBVOL_GETFLAGS:
4860 return btrfs_ioctl_subvol_getflags(file, argp);
4861 case BTRFS_IOC_SUBVOL_SETFLAGS:
4862 return btrfs_ioctl_subvol_setflags(file, argp);
4863 case BTRFS_IOC_DEFAULT_SUBVOL:
4864 return btrfs_ioctl_default_subvol(file, argp);
4865 case BTRFS_IOC_DEFRAG:
4866 return btrfs_ioctl_defrag(file, NULL);
4867 case BTRFS_IOC_DEFRAG_RANGE:
4868 return btrfs_ioctl_defrag(file, argp);
4869 case BTRFS_IOC_RESIZE:
4870 return btrfs_ioctl_resize(file, argp);
4871 case BTRFS_IOC_ADD_DEV:
4872 return btrfs_ioctl_add_dev(fs_info, argp);
4873 case BTRFS_IOC_RM_DEV:
4874 return btrfs_ioctl_rm_dev(file, argp);
4875 case BTRFS_IOC_RM_DEV_V2:
4876 return btrfs_ioctl_rm_dev_v2(file, argp);
4877 case BTRFS_IOC_FS_INFO:
4878 return btrfs_ioctl_fs_info(fs_info, argp);
4879 case BTRFS_IOC_DEV_INFO:
4880 return btrfs_ioctl_dev_info(fs_info, argp);
4881 case BTRFS_IOC_BALANCE:
4882 return btrfs_ioctl_balance(file, NULL);
4883 case BTRFS_IOC_TREE_SEARCH:
4884 return btrfs_ioctl_tree_search(file, argp);
4885 case BTRFS_IOC_TREE_SEARCH_V2:
4886 return btrfs_ioctl_tree_search_v2(file, argp);
4887 case BTRFS_IOC_INO_LOOKUP:
4888 return btrfs_ioctl_ino_lookup(file, argp);
4889 case BTRFS_IOC_INO_PATHS:
4890 return btrfs_ioctl_ino_to_path(root, argp);
4891 case BTRFS_IOC_LOGICAL_INO:
4892 return btrfs_ioctl_logical_to_ino(fs_info, argp, 1);
4893 case BTRFS_IOC_LOGICAL_INO_V2:
4894 return btrfs_ioctl_logical_to_ino(fs_info, argp, 2);
4895 case BTRFS_IOC_SPACE_INFO:
4896 return btrfs_ioctl_space_info(fs_info, argp);
4897 case BTRFS_IOC_SYNC: {
4898 int ret;
4899
4900 ret = btrfs_start_delalloc_roots(fs_info, -1);
4901 if (ret)
4902 return ret;
4903 ret = btrfs_sync_fs(inode->i_sb, 1);
4904 /*
4905 * The transaction thread may want to do more work,
4906 * namely it pokes the cleaner kthread that will start
4907 * processing uncleaned subvols.
4908 */
4909 wake_up_process(fs_info->transaction_kthread);
4910 return ret;
4911 }
4912 case BTRFS_IOC_START_SYNC:
4913 return btrfs_ioctl_start_sync(root, argp);
4914 case BTRFS_IOC_WAIT_SYNC:
4915 return btrfs_ioctl_wait_sync(fs_info, argp);
4916 case BTRFS_IOC_SCRUB:
4917 return btrfs_ioctl_scrub(file, argp);
4918 case BTRFS_IOC_SCRUB_CANCEL:
4919 return btrfs_ioctl_scrub_cancel(fs_info);
4920 case BTRFS_IOC_SCRUB_PROGRESS:
4921 return btrfs_ioctl_scrub_progress(fs_info, argp);
4922 case BTRFS_IOC_BALANCE_V2:
4923 return btrfs_ioctl_balance(file, argp);
4924 case BTRFS_IOC_BALANCE_CTL:
4925 return btrfs_ioctl_balance_ctl(fs_info, arg);
4926 case BTRFS_IOC_BALANCE_PROGRESS:
4927 return btrfs_ioctl_balance_progress(fs_info, argp);
4928 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
4929 return btrfs_ioctl_set_received_subvol(file, argp);
4930#ifdef CONFIG_64BIT
4931 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
4932 return btrfs_ioctl_set_received_subvol_32(file, argp);
4933#endif
4934 case BTRFS_IOC_SEND:
4935 return _btrfs_ioctl_send(file, argp, false);
4936#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4937 case BTRFS_IOC_SEND_32:
4938 return _btrfs_ioctl_send(file, argp, true);
4939#endif
4940 case BTRFS_IOC_GET_DEV_STATS:
4941 return btrfs_ioctl_get_dev_stats(fs_info, argp);
4942 case BTRFS_IOC_QUOTA_CTL:
4943 return btrfs_ioctl_quota_ctl(file, argp);
4944 case BTRFS_IOC_QGROUP_ASSIGN:
4945 return btrfs_ioctl_qgroup_assign(file, argp);
4946 case BTRFS_IOC_QGROUP_CREATE:
4947 return btrfs_ioctl_qgroup_create(file, argp);
4948 case BTRFS_IOC_QGROUP_LIMIT:
4949 return btrfs_ioctl_qgroup_limit(file, argp);
4950 case BTRFS_IOC_QUOTA_RESCAN:
4951 return btrfs_ioctl_quota_rescan(file, argp);
4952 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
4953 return btrfs_ioctl_quota_rescan_status(fs_info, argp);
4954 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
4955 return btrfs_ioctl_quota_rescan_wait(fs_info, argp);
4956 case BTRFS_IOC_DEV_REPLACE:
4957 return btrfs_ioctl_dev_replace(fs_info, argp);
4958 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
4959 return btrfs_ioctl_get_supported_features(argp);
4960 case BTRFS_IOC_GET_FEATURES:
4961 return btrfs_ioctl_get_features(fs_info, argp);
4962 case BTRFS_IOC_SET_FEATURES:
4963 return btrfs_ioctl_set_features(file, argp);
4964 case FS_IOC_FSGETXATTR:
4965 return btrfs_ioctl_fsgetxattr(file, argp);
4966 case FS_IOC_FSSETXATTR:
4967 return btrfs_ioctl_fssetxattr(file, argp);
4968 case BTRFS_IOC_GET_SUBVOL_INFO:
4969 return btrfs_ioctl_get_subvol_info(file, argp);
4970 case BTRFS_IOC_GET_SUBVOL_ROOTREF:
4971 return btrfs_ioctl_get_subvol_rootref(file, argp);
4972 case BTRFS_IOC_INO_LOOKUP_USER:
4973 return btrfs_ioctl_ino_lookup_user(file, argp);
4974 }
4975
4976 return -ENOTTY;
4977}
4978
4979#ifdef CONFIG_COMPAT
4980long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
4981{
4982 /*
4983 * These all access 32-bit values anyway so no further
4984 * handling is necessary.
4985 */
4986 switch (cmd) {
4987 case FS_IOC32_GETFLAGS:
4988 cmd = FS_IOC_GETFLAGS;
4989 break;
4990 case FS_IOC32_SETFLAGS:
4991 cmd = FS_IOC_SETFLAGS;
4992 break;
4993 case FS_IOC32_GETVERSION:
4994 cmd = FS_IOC_GETVERSION;
4995 break;
4996 }
4997
4998 return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
4999}
5000#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 <linux/uuid.h>
45#include <linux/btrfs.h>
46#include <linux/uaccess.h>
47#include "ctree.h"
48#include "disk-io.h"
49#include "transaction.h"
50#include "btrfs_inode.h"
51#include "print-tree.h"
52#include "volumes.h"
53#include "locking.h"
54#include "inode-map.h"
55#include "backref.h"
56#include "rcu-string.h"
57#include "send.h"
58#include "dev-replace.h"
59#include "props.h"
60#include "sysfs.h"
61
62#ifdef CONFIG_64BIT
63/* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
64 * structures are incorrect, as the timespec structure from userspace
65 * is 4 bytes too small. We define these alternatives here to teach
66 * the kernel about the 32-bit struct packing.
67 */
68struct btrfs_ioctl_timespec_32 {
69 __u64 sec;
70 __u32 nsec;
71} __attribute__ ((__packed__));
72
73struct btrfs_ioctl_received_subvol_args_32 {
74 char uuid[BTRFS_UUID_SIZE]; /* in */
75 __u64 stransid; /* in */
76 __u64 rtransid; /* out */
77 struct btrfs_ioctl_timespec_32 stime; /* in */
78 struct btrfs_ioctl_timespec_32 rtime; /* out */
79 __u64 flags; /* in */
80 __u64 reserved[16]; /* in */
81} __attribute__ ((__packed__));
82
83#define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
84 struct btrfs_ioctl_received_subvol_args_32)
85#endif
86
87
88static int btrfs_clone(struct inode *src, struct inode *inode,
89 u64 off, u64 olen, u64 olen_aligned, u64 destoff);
90
91/* Mask out flags that are inappropriate for the given type of inode. */
92static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
93{
94 if (S_ISDIR(mode))
95 return flags;
96 else if (S_ISREG(mode))
97 return flags & ~FS_DIRSYNC_FL;
98 else
99 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
100}
101
102/*
103 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
104 */
105static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
106{
107 unsigned int iflags = 0;
108
109 if (flags & BTRFS_INODE_SYNC)
110 iflags |= FS_SYNC_FL;
111 if (flags & BTRFS_INODE_IMMUTABLE)
112 iflags |= FS_IMMUTABLE_FL;
113 if (flags & BTRFS_INODE_APPEND)
114 iflags |= FS_APPEND_FL;
115 if (flags & BTRFS_INODE_NODUMP)
116 iflags |= FS_NODUMP_FL;
117 if (flags & BTRFS_INODE_NOATIME)
118 iflags |= FS_NOATIME_FL;
119 if (flags & BTRFS_INODE_DIRSYNC)
120 iflags |= FS_DIRSYNC_FL;
121 if (flags & BTRFS_INODE_NODATACOW)
122 iflags |= FS_NOCOW_FL;
123
124 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
125 iflags |= FS_COMPR_FL;
126 else if (flags & BTRFS_INODE_NOCOMPRESS)
127 iflags |= FS_NOCOMP_FL;
128
129 return iflags;
130}
131
132/*
133 * Update inode->i_flags based on the btrfs internal flags.
134 */
135void btrfs_update_iflags(struct inode *inode)
136{
137 struct btrfs_inode *ip = BTRFS_I(inode);
138
139 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
140
141 if (ip->flags & BTRFS_INODE_SYNC)
142 inode->i_flags |= S_SYNC;
143 if (ip->flags & BTRFS_INODE_IMMUTABLE)
144 inode->i_flags |= S_IMMUTABLE;
145 if (ip->flags & BTRFS_INODE_APPEND)
146 inode->i_flags |= S_APPEND;
147 if (ip->flags & BTRFS_INODE_NOATIME)
148 inode->i_flags |= S_NOATIME;
149 if (ip->flags & BTRFS_INODE_DIRSYNC)
150 inode->i_flags |= S_DIRSYNC;
151}
152
153/*
154 * Inherit flags from the parent inode.
155 *
156 * Currently only the compression flags and the cow flags are inherited.
157 */
158void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
159{
160 unsigned int flags;
161
162 if (!dir)
163 return;
164
165 flags = BTRFS_I(dir)->flags;
166
167 if (flags & BTRFS_INODE_NOCOMPRESS) {
168 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
169 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
170 } else if (flags & BTRFS_INODE_COMPRESS) {
171 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
172 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
173 }
174
175 if (flags & BTRFS_INODE_NODATACOW) {
176 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
177 if (S_ISREG(inode->i_mode))
178 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
179 }
180
181 btrfs_update_iflags(inode);
182}
183
184static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
185{
186 struct btrfs_inode *ip = BTRFS_I(file_inode(file));
187 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
188
189 if (copy_to_user(arg, &flags, sizeof(flags)))
190 return -EFAULT;
191 return 0;
192}
193
194static int check_flags(unsigned int flags)
195{
196 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
197 FS_NOATIME_FL | FS_NODUMP_FL | \
198 FS_SYNC_FL | FS_DIRSYNC_FL | \
199 FS_NOCOMP_FL | FS_COMPR_FL |
200 FS_NOCOW_FL))
201 return -EOPNOTSUPP;
202
203 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
204 return -EINVAL;
205
206 return 0;
207}
208
209static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
210{
211 struct inode *inode = file_inode(file);
212 struct btrfs_inode *ip = BTRFS_I(inode);
213 struct btrfs_root *root = ip->root;
214 struct btrfs_trans_handle *trans;
215 unsigned int flags, oldflags;
216 int ret;
217 u64 ip_oldflags;
218 unsigned int i_oldflags;
219 umode_t mode;
220
221 if (!inode_owner_or_capable(inode))
222 return -EPERM;
223
224 if (btrfs_root_readonly(root))
225 return -EROFS;
226
227 if (copy_from_user(&flags, arg, sizeof(flags)))
228 return -EFAULT;
229
230 ret = check_flags(flags);
231 if (ret)
232 return ret;
233
234 ret = mnt_want_write_file(file);
235 if (ret)
236 return ret;
237
238 mutex_lock(&inode->i_mutex);
239
240 ip_oldflags = ip->flags;
241 i_oldflags = inode->i_flags;
242 mode = inode->i_mode;
243
244 flags = btrfs_mask_flags(inode->i_mode, flags);
245 oldflags = btrfs_flags_to_ioctl(ip->flags);
246 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
247 if (!capable(CAP_LINUX_IMMUTABLE)) {
248 ret = -EPERM;
249 goto out_unlock;
250 }
251 }
252
253 if (flags & FS_SYNC_FL)
254 ip->flags |= BTRFS_INODE_SYNC;
255 else
256 ip->flags &= ~BTRFS_INODE_SYNC;
257 if (flags & FS_IMMUTABLE_FL)
258 ip->flags |= BTRFS_INODE_IMMUTABLE;
259 else
260 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
261 if (flags & FS_APPEND_FL)
262 ip->flags |= BTRFS_INODE_APPEND;
263 else
264 ip->flags &= ~BTRFS_INODE_APPEND;
265 if (flags & FS_NODUMP_FL)
266 ip->flags |= BTRFS_INODE_NODUMP;
267 else
268 ip->flags &= ~BTRFS_INODE_NODUMP;
269 if (flags & FS_NOATIME_FL)
270 ip->flags |= BTRFS_INODE_NOATIME;
271 else
272 ip->flags &= ~BTRFS_INODE_NOATIME;
273 if (flags & FS_DIRSYNC_FL)
274 ip->flags |= BTRFS_INODE_DIRSYNC;
275 else
276 ip->flags &= ~BTRFS_INODE_DIRSYNC;
277 if (flags & FS_NOCOW_FL) {
278 if (S_ISREG(mode)) {
279 /*
280 * It's safe to turn csums off here, no extents exist.
281 * Otherwise we want the flag to reflect the real COW
282 * status of the file and will not set it.
283 */
284 if (inode->i_size == 0)
285 ip->flags |= BTRFS_INODE_NODATACOW
286 | BTRFS_INODE_NODATASUM;
287 } else {
288 ip->flags |= BTRFS_INODE_NODATACOW;
289 }
290 } else {
291 /*
292 * Revert back under same assuptions as above
293 */
294 if (S_ISREG(mode)) {
295 if (inode->i_size == 0)
296 ip->flags &= ~(BTRFS_INODE_NODATACOW
297 | BTRFS_INODE_NODATASUM);
298 } else {
299 ip->flags &= ~BTRFS_INODE_NODATACOW;
300 }
301 }
302
303 /*
304 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
305 * flag may be changed automatically if compression code won't make
306 * things smaller.
307 */
308 if (flags & FS_NOCOMP_FL) {
309 ip->flags &= ~BTRFS_INODE_COMPRESS;
310 ip->flags |= BTRFS_INODE_NOCOMPRESS;
311
312 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
313 if (ret && ret != -ENODATA)
314 goto out_drop;
315 } else if (flags & FS_COMPR_FL) {
316 const char *comp;
317
318 ip->flags |= BTRFS_INODE_COMPRESS;
319 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
320
321 if (root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
322 comp = "lzo";
323 else
324 comp = "zlib";
325 ret = btrfs_set_prop(inode, "btrfs.compression",
326 comp, strlen(comp), 0);
327 if (ret)
328 goto out_drop;
329
330 } else {
331 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
332 }
333
334 trans = btrfs_start_transaction(root, 1);
335 if (IS_ERR(trans)) {
336 ret = PTR_ERR(trans);
337 goto out_drop;
338 }
339
340 btrfs_update_iflags(inode);
341 inode_inc_iversion(inode);
342 inode->i_ctime = CURRENT_TIME;
343 ret = btrfs_update_inode(trans, root, inode);
344
345 btrfs_end_transaction(trans, root);
346 out_drop:
347 if (ret) {
348 ip->flags = ip_oldflags;
349 inode->i_flags = i_oldflags;
350 }
351
352 out_unlock:
353 mutex_unlock(&inode->i_mutex);
354 mnt_drop_write_file(file);
355 return ret;
356}
357
358static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
359{
360 struct inode *inode = file_inode(file);
361
362 return put_user(inode->i_generation, arg);
363}
364
365static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
366{
367 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
368 struct btrfs_device *device;
369 struct request_queue *q;
370 struct fstrim_range range;
371 u64 minlen = ULLONG_MAX;
372 u64 num_devices = 0;
373 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
374 int ret;
375
376 if (!capable(CAP_SYS_ADMIN))
377 return -EPERM;
378
379 rcu_read_lock();
380 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
381 dev_list) {
382 if (!device->bdev)
383 continue;
384 q = bdev_get_queue(device->bdev);
385 if (blk_queue_discard(q)) {
386 num_devices++;
387 minlen = min((u64)q->limits.discard_granularity,
388 minlen);
389 }
390 }
391 rcu_read_unlock();
392
393 if (!num_devices)
394 return -EOPNOTSUPP;
395 if (copy_from_user(&range, arg, sizeof(range)))
396 return -EFAULT;
397 if (range.start > total_bytes ||
398 range.len < fs_info->sb->s_blocksize)
399 return -EINVAL;
400
401 range.len = min(range.len, total_bytes - range.start);
402 range.minlen = max(range.minlen, minlen);
403 ret = btrfs_trim_fs(fs_info->tree_root, &range);
404 if (ret < 0)
405 return ret;
406
407 if (copy_to_user(arg, &range, sizeof(range)))
408 return -EFAULT;
409
410 return 0;
411}
412
413int btrfs_is_empty_uuid(u8 *uuid)
414{
415 int i;
416
417 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
418 if (uuid[i])
419 return 0;
420 }
421 return 1;
422}
423
424static noinline int create_subvol(struct inode *dir,
425 struct dentry *dentry,
426 char *name, int namelen,
427 u64 *async_transid,
428 struct btrfs_qgroup_inherit *inherit)
429{
430 struct btrfs_trans_handle *trans;
431 struct btrfs_key key;
432 struct btrfs_root_item root_item;
433 struct btrfs_inode_item *inode_item;
434 struct extent_buffer *leaf;
435 struct btrfs_root *root = BTRFS_I(dir)->root;
436 struct btrfs_root *new_root;
437 struct btrfs_block_rsv block_rsv;
438 struct timespec cur_time = CURRENT_TIME;
439 struct inode *inode;
440 int ret;
441 int err;
442 u64 objectid;
443 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
444 u64 index = 0;
445 u64 qgroup_reserved;
446 uuid_le new_uuid;
447
448 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
449 if (ret)
450 return ret;
451
452 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
453 /*
454 * The same as the snapshot creation, please see the comment
455 * of create_snapshot().
456 */
457 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
458 8, &qgroup_reserved, false);
459 if (ret)
460 return ret;
461
462 trans = btrfs_start_transaction(root, 0);
463 if (IS_ERR(trans)) {
464 ret = PTR_ERR(trans);
465 btrfs_subvolume_release_metadata(root, &block_rsv,
466 qgroup_reserved);
467 return ret;
468 }
469 trans->block_rsv = &block_rsv;
470 trans->bytes_reserved = block_rsv.size;
471
472 ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
473 if (ret)
474 goto fail;
475
476 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
477 0, objectid, NULL, 0, 0, 0);
478 if (IS_ERR(leaf)) {
479 ret = PTR_ERR(leaf);
480 goto fail;
481 }
482
483 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
484 btrfs_set_header_bytenr(leaf, leaf->start);
485 btrfs_set_header_generation(leaf, trans->transid);
486 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
487 btrfs_set_header_owner(leaf, objectid);
488
489 write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(),
490 BTRFS_FSID_SIZE);
491 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
492 btrfs_header_chunk_tree_uuid(leaf),
493 BTRFS_UUID_SIZE);
494 btrfs_mark_buffer_dirty(leaf);
495
496 memset(&root_item, 0, sizeof(root_item));
497
498 inode_item = &root_item.inode;
499 btrfs_set_stack_inode_generation(inode_item, 1);
500 btrfs_set_stack_inode_size(inode_item, 3);
501 btrfs_set_stack_inode_nlink(inode_item, 1);
502 btrfs_set_stack_inode_nbytes(inode_item, root->leafsize);
503 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
504
505 btrfs_set_root_flags(&root_item, 0);
506 btrfs_set_root_limit(&root_item, 0);
507 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
508
509 btrfs_set_root_bytenr(&root_item, leaf->start);
510 btrfs_set_root_generation(&root_item, trans->transid);
511 btrfs_set_root_level(&root_item, 0);
512 btrfs_set_root_refs(&root_item, 1);
513 btrfs_set_root_used(&root_item, leaf->len);
514 btrfs_set_root_last_snapshot(&root_item, 0);
515
516 btrfs_set_root_generation_v2(&root_item,
517 btrfs_root_generation(&root_item));
518 uuid_le_gen(&new_uuid);
519 memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
520 btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
521 btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec);
522 root_item.ctime = root_item.otime;
523 btrfs_set_root_ctransid(&root_item, trans->transid);
524 btrfs_set_root_otransid(&root_item, trans->transid);
525
526 btrfs_tree_unlock(leaf);
527 free_extent_buffer(leaf);
528 leaf = NULL;
529
530 btrfs_set_root_dirid(&root_item, new_dirid);
531
532 key.objectid = objectid;
533 key.offset = 0;
534 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
535 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
536 &root_item);
537 if (ret)
538 goto fail;
539
540 key.offset = (u64)-1;
541 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
542 if (IS_ERR(new_root)) {
543 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
544 ret = PTR_ERR(new_root);
545 goto fail;
546 }
547
548 btrfs_record_root_in_trans(trans, new_root);
549
550 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
551 if (ret) {
552 /* We potentially lose an unused inode item here */
553 btrfs_abort_transaction(trans, root, ret);
554 goto fail;
555 }
556
557 /*
558 * insert the directory item
559 */
560 ret = btrfs_set_inode_index(dir, &index);
561 if (ret) {
562 btrfs_abort_transaction(trans, root, ret);
563 goto fail;
564 }
565
566 ret = btrfs_insert_dir_item(trans, root,
567 name, namelen, dir, &key,
568 BTRFS_FT_DIR, index);
569 if (ret) {
570 btrfs_abort_transaction(trans, root, ret);
571 goto fail;
572 }
573
574 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
575 ret = btrfs_update_inode(trans, root, dir);
576 BUG_ON(ret);
577
578 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
579 objectid, root->root_key.objectid,
580 btrfs_ino(dir), index, name, namelen);
581 BUG_ON(ret);
582
583 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
584 root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
585 objectid);
586 if (ret)
587 btrfs_abort_transaction(trans, root, ret);
588
589fail:
590 trans->block_rsv = NULL;
591 trans->bytes_reserved = 0;
592 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
593
594 if (async_transid) {
595 *async_transid = trans->transid;
596 err = btrfs_commit_transaction_async(trans, root, 1);
597 if (err)
598 err = btrfs_commit_transaction(trans, root);
599 } else {
600 err = btrfs_commit_transaction(trans, root);
601 }
602 if (err && !ret)
603 ret = err;
604
605 if (!ret) {
606 inode = btrfs_lookup_dentry(dir, dentry);
607 if (IS_ERR(inode))
608 return PTR_ERR(inode);
609 d_instantiate(dentry, inode);
610 }
611 return ret;
612}
613
614static void btrfs_wait_nocow_write(struct btrfs_root *root)
615{
616 s64 writers;
617 DEFINE_WAIT(wait);
618
619 do {
620 prepare_to_wait(&root->subv_writers->wait, &wait,
621 TASK_UNINTERRUPTIBLE);
622
623 writers = percpu_counter_sum(&root->subv_writers->counter);
624 if (writers)
625 schedule();
626
627 finish_wait(&root->subv_writers->wait, &wait);
628 } while (writers);
629}
630
631static int create_snapshot(struct btrfs_root *root, struct inode *dir,
632 struct dentry *dentry, char *name, int namelen,
633 u64 *async_transid, bool readonly,
634 struct btrfs_qgroup_inherit *inherit)
635{
636 struct inode *inode;
637 struct btrfs_pending_snapshot *pending_snapshot;
638 struct btrfs_trans_handle *trans;
639 int ret;
640
641 if (!root->ref_cows)
642 return -EINVAL;
643
644 atomic_inc(&root->will_be_snapshoted);
645 smp_mb__after_atomic_inc();
646 btrfs_wait_nocow_write(root);
647
648 ret = btrfs_start_delalloc_inodes(root, 0);
649 if (ret)
650 goto out;
651
652 btrfs_wait_ordered_extents(root, -1);
653
654 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
655 if (!pending_snapshot) {
656 ret = -ENOMEM;
657 goto out;
658 }
659
660 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
661 BTRFS_BLOCK_RSV_TEMP);
662 /*
663 * 1 - parent dir inode
664 * 2 - dir entries
665 * 1 - root item
666 * 2 - root ref/backref
667 * 1 - root of snapshot
668 * 1 - UUID item
669 */
670 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
671 &pending_snapshot->block_rsv, 8,
672 &pending_snapshot->qgroup_reserved,
673 false);
674 if (ret)
675 goto free;
676
677 pending_snapshot->dentry = dentry;
678 pending_snapshot->root = root;
679 pending_snapshot->readonly = readonly;
680 pending_snapshot->dir = dir;
681 pending_snapshot->inherit = inherit;
682
683 trans = btrfs_start_transaction(root, 0);
684 if (IS_ERR(trans)) {
685 ret = PTR_ERR(trans);
686 goto fail;
687 }
688
689 spin_lock(&root->fs_info->trans_lock);
690 list_add(&pending_snapshot->list,
691 &trans->transaction->pending_snapshots);
692 spin_unlock(&root->fs_info->trans_lock);
693 if (async_transid) {
694 *async_transid = trans->transid;
695 ret = btrfs_commit_transaction_async(trans,
696 root->fs_info->extent_root, 1);
697 if (ret)
698 ret = btrfs_commit_transaction(trans, root);
699 } else {
700 ret = btrfs_commit_transaction(trans,
701 root->fs_info->extent_root);
702 }
703 if (ret)
704 goto fail;
705
706 ret = pending_snapshot->error;
707 if (ret)
708 goto fail;
709
710 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
711 if (ret)
712 goto fail;
713
714 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
715 if (IS_ERR(inode)) {
716 ret = PTR_ERR(inode);
717 goto fail;
718 }
719
720 d_instantiate(dentry, inode);
721 ret = 0;
722fail:
723 btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
724 &pending_snapshot->block_rsv,
725 pending_snapshot->qgroup_reserved);
726free:
727 kfree(pending_snapshot);
728out:
729 atomic_dec(&root->will_be_snapshoted);
730 return ret;
731}
732
733/* copy of check_sticky in fs/namei.c()
734* It's inline, so penalty for filesystems that don't use sticky bit is
735* minimal.
736*/
737static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
738{
739 kuid_t fsuid = current_fsuid();
740
741 if (!(dir->i_mode & S_ISVTX))
742 return 0;
743 if (uid_eq(inode->i_uid, fsuid))
744 return 0;
745 if (uid_eq(dir->i_uid, fsuid))
746 return 0;
747 return !capable(CAP_FOWNER);
748}
749
750/* copy of may_delete in fs/namei.c()
751 * Check whether we can remove a link victim from directory dir, check
752 * whether the type of victim is right.
753 * 1. We can't do it if dir is read-only (done in permission())
754 * 2. We should have write and exec permissions on dir
755 * 3. We can't remove anything from append-only dir
756 * 4. We can't do anything with immutable dir (done in permission())
757 * 5. If the sticky bit on dir is set we should either
758 * a. be owner of dir, or
759 * b. be owner of victim, or
760 * c. have CAP_FOWNER capability
761 * 6. If the victim is append-only or immutable we can't do antyhing with
762 * links pointing to it.
763 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
764 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
765 * 9. We can't remove a root or mountpoint.
766 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
767 * nfs_async_unlink().
768 */
769
770static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
771{
772 int error;
773
774 if (!victim->d_inode)
775 return -ENOENT;
776
777 BUG_ON(victim->d_parent->d_inode != dir);
778 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
779
780 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
781 if (error)
782 return error;
783 if (IS_APPEND(dir))
784 return -EPERM;
785 if (btrfs_check_sticky(dir, victim->d_inode)||
786 IS_APPEND(victim->d_inode)||
787 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
788 return -EPERM;
789 if (isdir) {
790 if (!S_ISDIR(victim->d_inode->i_mode))
791 return -ENOTDIR;
792 if (IS_ROOT(victim))
793 return -EBUSY;
794 } else if (S_ISDIR(victim->d_inode->i_mode))
795 return -EISDIR;
796 if (IS_DEADDIR(dir))
797 return -ENOENT;
798 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
799 return -EBUSY;
800 return 0;
801}
802
803/* copy of may_create in fs/namei.c() */
804static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
805{
806 if (child->d_inode)
807 return -EEXIST;
808 if (IS_DEADDIR(dir))
809 return -ENOENT;
810 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
811}
812
813/*
814 * Create a new subvolume below @parent. This is largely modeled after
815 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
816 * inside this filesystem so it's quite a bit simpler.
817 */
818static noinline int btrfs_mksubvol(struct path *parent,
819 char *name, int namelen,
820 struct btrfs_root *snap_src,
821 u64 *async_transid, bool readonly,
822 struct btrfs_qgroup_inherit *inherit)
823{
824 struct inode *dir = parent->dentry->d_inode;
825 struct dentry *dentry;
826 int error;
827
828 error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
829 if (error == -EINTR)
830 return error;
831
832 dentry = lookup_one_len(name, parent->dentry, namelen);
833 error = PTR_ERR(dentry);
834 if (IS_ERR(dentry))
835 goto out_unlock;
836
837 error = -EEXIST;
838 if (dentry->d_inode)
839 goto out_dput;
840
841 error = btrfs_may_create(dir, dentry);
842 if (error)
843 goto out_dput;
844
845 /*
846 * even if this name doesn't exist, we may get hash collisions.
847 * check for them now when we can safely fail
848 */
849 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
850 dir->i_ino, name,
851 namelen);
852 if (error)
853 goto out_dput;
854
855 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
856
857 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
858 goto out_up_read;
859
860 if (snap_src) {
861 error = create_snapshot(snap_src, dir, dentry, name, namelen,
862 async_transid, readonly, inherit);
863 } else {
864 error = create_subvol(dir, dentry, name, namelen,
865 async_transid, inherit);
866 }
867 if (!error)
868 fsnotify_mkdir(dir, dentry);
869out_up_read:
870 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
871out_dput:
872 dput(dentry);
873out_unlock:
874 mutex_unlock(&dir->i_mutex);
875 return error;
876}
877
878/*
879 * When we're defragging a range, we don't want to kick it off again
880 * if it is really just waiting for delalloc to send it down.
881 * If we find a nice big extent or delalloc range for the bytes in the
882 * file you want to defrag, we return 0 to let you know to skip this
883 * part of the file
884 */
885static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
886{
887 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
888 struct extent_map *em = NULL;
889 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
890 u64 end;
891
892 read_lock(&em_tree->lock);
893 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
894 read_unlock(&em_tree->lock);
895
896 if (em) {
897 end = extent_map_end(em);
898 free_extent_map(em);
899 if (end - offset > thresh)
900 return 0;
901 }
902 /* if we already have a nice delalloc here, just stop */
903 thresh /= 2;
904 end = count_range_bits(io_tree, &offset, offset + thresh,
905 thresh, EXTENT_DELALLOC, 1);
906 if (end >= thresh)
907 return 0;
908 return 1;
909}
910
911/*
912 * helper function to walk through a file and find extents
913 * newer than a specific transid, and smaller than thresh.
914 *
915 * This is used by the defragging code to find new and small
916 * extents
917 */
918static int find_new_extents(struct btrfs_root *root,
919 struct inode *inode, u64 newer_than,
920 u64 *off, int thresh)
921{
922 struct btrfs_path *path;
923 struct btrfs_key min_key;
924 struct extent_buffer *leaf;
925 struct btrfs_file_extent_item *extent;
926 int type;
927 int ret;
928 u64 ino = btrfs_ino(inode);
929
930 path = btrfs_alloc_path();
931 if (!path)
932 return -ENOMEM;
933
934 min_key.objectid = ino;
935 min_key.type = BTRFS_EXTENT_DATA_KEY;
936 min_key.offset = *off;
937
938 while (1) {
939 path->keep_locks = 1;
940 ret = btrfs_search_forward(root, &min_key, path, newer_than);
941 if (ret != 0)
942 goto none;
943 path->keep_locks = 0;
944 btrfs_unlock_up_safe(path, 1);
945process_slot:
946 if (min_key.objectid != ino)
947 goto none;
948 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
949 goto none;
950
951 leaf = path->nodes[0];
952 extent = btrfs_item_ptr(leaf, path->slots[0],
953 struct btrfs_file_extent_item);
954
955 type = btrfs_file_extent_type(leaf, extent);
956 if (type == BTRFS_FILE_EXTENT_REG &&
957 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
958 check_defrag_in_cache(inode, min_key.offset, thresh)) {
959 *off = min_key.offset;
960 btrfs_free_path(path);
961 return 0;
962 }
963
964 path->slots[0]++;
965 if (path->slots[0] < btrfs_header_nritems(leaf)) {
966 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
967 goto process_slot;
968 }
969
970 if (min_key.offset == (u64)-1)
971 goto none;
972
973 min_key.offset++;
974 btrfs_release_path(path);
975 }
976none:
977 btrfs_free_path(path);
978 return -ENOENT;
979}
980
981static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
982{
983 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
984 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
985 struct extent_map *em;
986 u64 len = PAGE_CACHE_SIZE;
987
988 /*
989 * hopefully we have this extent in the tree already, try without
990 * the full extent lock
991 */
992 read_lock(&em_tree->lock);
993 em = lookup_extent_mapping(em_tree, start, len);
994 read_unlock(&em_tree->lock);
995
996 if (!em) {
997 struct extent_state *cached = NULL;
998 u64 end = start + len - 1;
999
1000 /* get the big lock and read metadata off disk */
1001 lock_extent_bits(io_tree, start, end, 0, &cached);
1002 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
1003 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
1004
1005 if (IS_ERR(em))
1006 return NULL;
1007 }
1008
1009 return em;
1010}
1011
1012static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1013{
1014 struct extent_map *next;
1015 bool ret = true;
1016
1017 /* this is the last extent */
1018 if (em->start + em->len >= i_size_read(inode))
1019 return false;
1020
1021 next = defrag_lookup_extent(inode, em->start + em->len);
1022 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE ||
1023 (em->block_start + em->block_len == next->block_start))
1024 ret = false;
1025
1026 free_extent_map(next);
1027 return ret;
1028}
1029
1030static int should_defrag_range(struct inode *inode, u64 start, int thresh,
1031 u64 *last_len, u64 *skip, u64 *defrag_end,
1032 int compress)
1033{
1034 struct extent_map *em;
1035 int ret = 1;
1036 bool next_mergeable = true;
1037
1038 /*
1039 * make sure that once we start defragging an extent, we keep on
1040 * defragging it
1041 */
1042 if (start < *defrag_end)
1043 return 1;
1044
1045 *skip = 0;
1046
1047 em = defrag_lookup_extent(inode, start);
1048 if (!em)
1049 return 0;
1050
1051 /* this will cover holes, and inline extents */
1052 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1053 ret = 0;
1054 goto out;
1055 }
1056
1057 next_mergeable = defrag_check_next_extent(inode, em);
1058
1059 /*
1060 * we hit a real extent, if it is big or the next extent is not a
1061 * real extent, don't bother defragging it
1062 */
1063 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1064 (em->len >= thresh || !next_mergeable))
1065 ret = 0;
1066out:
1067 /*
1068 * last_len ends up being a counter of how many bytes we've defragged.
1069 * every time we choose not to defrag an extent, we reset *last_len
1070 * so that the next tiny extent will force a defrag.
1071 *
1072 * The end result of this is that tiny extents before a single big
1073 * extent will force at least part of that big extent to be defragged.
1074 */
1075 if (ret) {
1076 *defrag_end = extent_map_end(em);
1077 } else {
1078 *last_len = 0;
1079 *skip = extent_map_end(em);
1080 *defrag_end = 0;
1081 }
1082
1083 free_extent_map(em);
1084 return ret;
1085}
1086
1087/*
1088 * it doesn't do much good to defrag one or two pages
1089 * at a time. This pulls in a nice chunk of pages
1090 * to COW and defrag.
1091 *
1092 * It also makes sure the delalloc code has enough
1093 * dirty data to avoid making new small extents as part
1094 * of the defrag
1095 *
1096 * It's a good idea to start RA on this range
1097 * before calling this.
1098 */
1099static int cluster_pages_for_defrag(struct inode *inode,
1100 struct page **pages,
1101 unsigned long start_index,
1102 unsigned long num_pages)
1103{
1104 unsigned long file_end;
1105 u64 isize = i_size_read(inode);
1106 u64 page_start;
1107 u64 page_end;
1108 u64 page_cnt;
1109 int ret;
1110 int i;
1111 int i_done;
1112 struct btrfs_ordered_extent *ordered;
1113 struct extent_state *cached_state = NULL;
1114 struct extent_io_tree *tree;
1115 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1116
1117 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1118 if (!isize || start_index > file_end)
1119 return 0;
1120
1121 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1122
1123 ret = btrfs_delalloc_reserve_space(inode,
1124 page_cnt << PAGE_CACHE_SHIFT);
1125 if (ret)
1126 return ret;
1127 i_done = 0;
1128 tree = &BTRFS_I(inode)->io_tree;
1129
1130 /* step one, lock all the pages */
1131 for (i = 0; i < page_cnt; i++) {
1132 struct page *page;
1133again:
1134 page = find_or_create_page(inode->i_mapping,
1135 start_index + i, mask);
1136 if (!page)
1137 break;
1138
1139 page_start = page_offset(page);
1140 page_end = page_start + PAGE_CACHE_SIZE - 1;
1141 while (1) {
1142 lock_extent_bits(tree, page_start, page_end,
1143 0, &cached_state);
1144 ordered = btrfs_lookup_ordered_extent(inode,
1145 page_start);
1146 unlock_extent_cached(tree, page_start, page_end,
1147 &cached_state, GFP_NOFS);
1148 if (!ordered)
1149 break;
1150
1151 unlock_page(page);
1152 btrfs_start_ordered_extent(inode, ordered, 1);
1153 btrfs_put_ordered_extent(ordered);
1154 lock_page(page);
1155 /*
1156 * we unlocked the page above, so we need check if
1157 * it was released or not.
1158 */
1159 if (page->mapping != inode->i_mapping) {
1160 unlock_page(page);
1161 page_cache_release(page);
1162 goto again;
1163 }
1164 }
1165
1166 if (!PageUptodate(page)) {
1167 btrfs_readpage(NULL, page);
1168 lock_page(page);
1169 if (!PageUptodate(page)) {
1170 unlock_page(page);
1171 page_cache_release(page);
1172 ret = -EIO;
1173 break;
1174 }
1175 }
1176
1177 if (page->mapping != inode->i_mapping) {
1178 unlock_page(page);
1179 page_cache_release(page);
1180 goto again;
1181 }
1182
1183 pages[i] = page;
1184 i_done++;
1185 }
1186 if (!i_done || ret)
1187 goto out;
1188
1189 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1190 goto out;
1191
1192 /*
1193 * so now we have a nice long stream of locked
1194 * and up to date pages, lets wait on them
1195 */
1196 for (i = 0; i < i_done; i++)
1197 wait_on_page_writeback(pages[i]);
1198
1199 page_start = page_offset(pages[0]);
1200 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1201
1202 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1203 page_start, page_end - 1, 0, &cached_state);
1204 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1205 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1206 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1207 &cached_state, GFP_NOFS);
1208
1209 if (i_done != page_cnt) {
1210 spin_lock(&BTRFS_I(inode)->lock);
1211 BTRFS_I(inode)->outstanding_extents++;
1212 spin_unlock(&BTRFS_I(inode)->lock);
1213 btrfs_delalloc_release_space(inode,
1214 (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1215 }
1216
1217
1218 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1219 &cached_state, GFP_NOFS);
1220
1221 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1222 page_start, page_end - 1, &cached_state,
1223 GFP_NOFS);
1224
1225 for (i = 0; i < i_done; i++) {
1226 clear_page_dirty_for_io(pages[i]);
1227 ClearPageChecked(pages[i]);
1228 set_page_extent_mapped(pages[i]);
1229 set_page_dirty(pages[i]);
1230 unlock_page(pages[i]);
1231 page_cache_release(pages[i]);
1232 }
1233 return i_done;
1234out:
1235 for (i = 0; i < i_done; i++) {
1236 unlock_page(pages[i]);
1237 page_cache_release(pages[i]);
1238 }
1239 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1240 return ret;
1241
1242}
1243
1244int btrfs_defrag_file(struct inode *inode, struct file *file,
1245 struct btrfs_ioctl_defrag_range_args *range,
1246 u64 newer_than, unsigned long max_to_defrag)
1247{
1248 struct btrfs_root *root = BTRFS_I(inode)->root;
1249 struct file_ra_state *ra = NULL;
1250 unsigned long last_index;
1251 u64 isize = i_size_read(inode);
1252 u64 last_len = 0;
1253 u64 skip = 0;
1254 u64 defrag_end = 0;
1255 u64 newer_off = range->start;
1256 unsigned long i;
1257 unsigned long ra_index = 0;
1258 int ret;
1259 int defrag_count = 0;
1260 int compress_type = BTRFS_COMPRESS_ZLIB;
1261 int extent_thresh = range->extent_thresh;
1262 unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1263 unsigned long cluster = max_cluster;
1264 u64 new_align = ~((u64)128 * 1024 - 1);
1265 struct page **pages = NULL;
1266
1267 if (isize == 0)
1268 return 0;
1269
1270 if (range->start >= isize)
1271 return -EINVAL;
1272
1273 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1274 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1275 return -EINVAL;
1276 if (range->compress_type)
1277 compress_type = range->compress_type;
1278 }
1279
1280 if (extent_thresh == 0)
1281 extent_thresh = 256 * 1024;
1282
1283 /*
1284 * if we were not given a file, allocate a readahead
1285 * context
1286 */
1287 if (!file) {
1288 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1289 if (!ra)
1290 return -ENOMEM;
1291 file_ra_state_init(ra, inode->i_mapping);
1292 } else {
1293 ra = &file->f_ra;
1294 }
1295
1296 pages = kmalloc_array(max_cluster, sizeof(struct page *),
1297 GFP_NOFS);
1298 if (!pages) {
1299 ret = -ENOMEM;
1300 goto out_ra;
1301 }
1302
1303 /* find the last page to defrag */
1304 if (range->start + range->len > range->start) {
1305 last_index = min_t(u64, isize - 1,
1306 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1307 } else {
1308 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1309 }
1310
1311 if (newer_than) {
1312 ret = find_new_extents(root, inode, newer_than,
1313 &newer_off, 64 * 1024);
1314 if (!ret) {
1315 range->start = newer_off;
1316 /*
1317 * we always align our defrag to help keep
1318 * the extents in the file evenly spaced
1319 */
1320 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1321 } else
1322 goto out_ra;
1323 } else {
1324 i = range->start >> PAGE_CACHE_SHIFT;
1325 }
1326 if (!max_to_defrag)
1327 max_to_defrag = last_index + 1;
1328
1329 /*
1330 * make writeback starts from i, so the defrag range can be
1331 * written sequentially.
1332 */
1333 if (i < inode->i_mapping->writeback_index)
1334 inode->i_mapping->writeback_index = i;
1335
1336 while (i <= last_index && defrag_count < max_to_defrag &&
1337 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1338 PAGE_CACHE_SHIFT)) {
1339 /*
1340 * make sure we stop running if someone unmounts
1341 * the FS
1342 */
1343 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1344 break;
1345
1346 if (btrfs_defrag_cancelled(root->fs_info)) {
1347 printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n");
1348 ret = -EAGAIN;
1349 break;
1350 }
1351
1352 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1353 extent_thresh, &last_len, &skip,
1354 &defrag_end, range->flags &
1355 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1356 unsigned long next;
1357 /*
1358 * the should_defrag function tells us how much to skip
1359 * bump our counter by the suggested amount
1360 */
1361 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1362 i = max(i + 1, next);
1363 continue;
1364 }
1365
1366 if (!newer_than) {
1367 cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1368 PAGE_CACHE_SHIFT) - i;
1369 cluster = min(cluster, max_cluster);
1370 } else {
1371 cluster = max_cluster;
1372 }
1373
1374 if (i + cluster > ra_index) {
1375 ra_index = max(i, ra_index);
1376 btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1377 cluster);
1378 ra_index += max_cluster;
1379 }
1380
1381 mutex_lock(&inode->i_mutex);
1382 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1383 BTRFS_I(inode)->force_compress = compress_type;
1384 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1385 if (ret < 0) {
1386 mutex_unlock(&inode->i_mutex);
1387 goto out_ra;
1388 }
1389
1390 defrag_count += ret;
1391 balance_dirty_pages_ratelimited(inode->i_mapping);
1392 mutex_unlock(&inode->i_mutex);
1393
1394 if (newer_than) {
1395 if (newer_off == (u64)-1)
1396 break;
1397
1398 if (ret > 0)
1399 i += ret;
1400
1401 newer_off = max(newer_off + 1,
1402 (u64)i << PAGE_CACHE_SHIFT);
1403
1404 ret = find_new_extents(root, inode,
1405 newer_than, &newer_off,
1406 64 * 1024);
1407 if (!ret) {
1408 range->start = newer_off;
1409 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1410 } else {
1411 break;
1412 }
1413 } else {
1414 if (ret > 0) {
1415 i += ret;
1416 last_len += ret << PAGE_CACHE_SHIFT;
1417 } else {
1418 i++;
1419 last_len = 0;
1420 }
1421 }
1422 }
1423
1424 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1425 filemap_flush(inode->i_mapping);
1426 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1427 &BTRFS_I(inode)->runtime_flags))
1428 filemap_flush(inode->i_mapping);
1429 }
1430
1431 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1432 /* the filemap_flush will queue IO into the worker threads, but
1433 * we have to make sure the IO is actually started and that
1434 * ordered extents get created before we return
1435 */
1436 atomic_inc(&root->fs_info->async_submit_draining);
1437 while (atomic_read(&root->fs_info->nr_async_submits) ||
1438 atomic_read(&root->fs_info->async_delalloc_pages)) {
1439 wait_event(root->fs_info->async_submit_wait,
1440 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1441 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1442 }
1443 atomic_dec(&root->fs_info->async_submit_draining);
1444 }
1445
1446 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1447 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1448 }
1449
1450 ret = defrag_count;
1451
1452out_ra:
1453 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1454 mutex_lock(&inode->i_mutex);
1455 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1456 mutex_unlock(&inode->i_mutex);
1457 }
1458 if (!file)
1459 kfree(ra);
1460 kfree(pages);
1461 return ret;
1462}
1463
1464static noinline int btrfs_ioctl_resize(struct file *file,
1465 void __user *arg)
1466{
1467 u64 new_size;
1468 u64 old_size;
1469 u64 devid = 1;
1470 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
1471 struct btrfs_ioctl_vol_args *vol_args;
1472 struct btrfs_trans_handle *trans;
1473 struct btrfs_device *device = NULL;
1474 char *sizestr;
1475 char *retptr;
1476 char *devstr = NULL;
1477 int ret = 0;
1478 int mod = 0;
1479
1480 if (!capable(CAP_SYS_ADMIN))
1481 return -EPERM;
1482
1483 ret = mnt_want_write_file(file);
1484 if (ret)
1485 return ret;
1486
1487 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1488 1)) {
1489 mnt_drop_write_file(file);
1490 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1491 }
1492
1493 mutex_lock(&root->fs_info->volume_mutex);
1494 vol_args = memdup_user(arg, sizeof(*vol_args));
1495 if (IS_ERR(vol_args)) {
1496 ret = PTR_ERR(vol_args);
1497 goto out;
1498 }
1499
1500 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1501
1502 sizestr = vol_args->name;
1503 devstr = strchr(sizestr, ':');
1504 if (devstr) {
1505 char *end;
1506 sizestr = devstr + 1;
1507 *devstr = '\0';
1508 devstr = vol_args->name;
1509 devid = simple_strtoull(devstr, &end, 10);
1510 if (!devid) {
1511 ret = -EINVAL;
1512 goto out_free;
1513 }
1514 btrfs_info(root->fs_info, "resizing devid %llu", devid);
1515 }
1516
1517 device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1518 if (!device) {
1519 btrfs_info(root->fs_info, "resizer unable to find device %llu",
1520 devid);
1521 ret = -ENODEV;
1522 goto out_free;
1523 }
1524
1525 if (!device->writeable) {
1526 btrfs_info(root->fs_info,
1527 "resizer unable to apply on readonly device %llu",
1528 devid);
1529 ret = -EPERM;
1530 goto out_free;
1531 }
1532
1533 if (!strcmp(sizestr, "max"))
1534 new_size = device->bdev->bd_inode->i_size;
1535 else {
1536 if (sizestr[0] == '-') {
1537 mod = -1;
1538 sizestr++;
1539 } else if (sizestr[0] == '+') {
1540 mod = 1;
1541 sizestr++;
1542 }
1543 new_size = memparse(sizestr, &retptr);
1544 if (*retptr != '\0' || new_size == 0) {
1545 ret = -EINVAL;
1546 goto out_free;
1547 }
1548 }
1549
1550 if (device->is_tgtdev_for_dev_replace) {
1551 ret = -EPERM;
1552 goto out_free;
1553 }
1554
1555 old_size = device->total_bytes;
1556
1557 if (mod < 0) {
1558 if (new_size > old_size) {
1559 ret = -EINVAL;
1560 goto out_free;
1561 }
1562 new_size = old_size - new_size;
1563 } else if (mod > 0) {
1564 if (new_size > ULLONG_MAX - old_size) {
1565 ret = -EINVAL;
1566 goto out_free;
1567 }
1568 new_size = old_size + new_size;
1569 }
1570
1571 if (new_size < 256 * 1024 * 1024) {
1572 ret = -EINVAL;
1573 goto out_free;
1574 }
1575 if (new_size > device->bdev->bd_inode->i_size) {
1576 ret = -EFBIG;
1577 goto out_free;
1578 }
1579
1580 do_div(new_size, root->sectorsize);
1581 new_size *= root->sectorsize;
1582
1583 printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n",
1584 rcu_str_deref(device->name), new_size);
1585
1586 if (new_size > old_size) {
1587 trans = btrfs_start_transaction(root, 0);
1588 if (IS_ERR(trans)) {
1589 ret = PTR_ERR(trans);
1590 goto out_free;
1591 }
1592 ret = btrfs_grow_device(trans, device, new_size);
1593 btrfs_commit_transaction(trans, root);
1594 } else if (new_size < old_size) {
1595 ret = btrfs_shrink_device(device, new_size);
1596 } /* equal, nothing need to do */
1597
1598out_free:
1599 kfree(vol_args);
1600out:
1601 mutex_unlock(&root->fs_info->volume_mutex);
1602 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1603 mnt_drop_write_file(file);
1604 return ret;
1605}
1606
1607static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1608 char *name, unsigned long fd, int subvol,
1609 u64 *transid, bool readonly,
1610 struct btrfs_qgroup_inherit *inherit)
1611{
1612 int namelen;
1613 int ret = 0;
1614
1615 ret = mnt_want_write_file(file);
1616 if (ret)
1617 goto out;
1618
1619 namelen = strlen(name);
1620 if (strchr(name, '/')) {
1621 ret = -EINVAL;
1622 goto out_drop_write;
1623 }
1624
1625 if (name[0] == '.' &&
1626 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1627 ret = -EEXIST;
1628 goto out_drop_write;
1629 }
1630
1631 if (subvol) {
1632 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1633 NULL, transid, readonly, inherit);
1634 } else {
1635 struct fd src = fdget(fd);
1636 struct inode *src_inode;
1637 if (!src.file) {
1638 ret = -EINVAL;
1639 goto out_drop_write;
1640 }
1641
1642 src_inode = file_inode(src.file);
1643 if (src_inode->i_sb != file_inode(file)->i_sb) {
1644 btrfs_info(BTRFS_I(src_inode)->root->fs_info,
1645 "Snapshot src from another FS");
1646 ret = -EXDEV;
1647 } else if (!inode_owner_or_capable(src_inode)) {
1648 /*
1649 * Subvolume creation is not restricted, but snapshots
1650 * are limited to own subvolumes only
1651 */
1652 ret = -EPERM;
1653 } else {
1654 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1655 BTRFS_I(src_inode)->root,
1656 transid, readonly, inherit);
1657 }
1658 fdput(src);
1659 }
1660out_drop_write:
1661 mnt_drop_write_file(file);
1662out:
1663 return ret;
1664}
1665
1666static noinline int btrfs_ioctl_snap_create(struct file *file,
1667 void __user *arg, int subvol)
1668{
1669 struct btrfs_ioctl_vol_args *vol_args;
1670 int ret;
1671
1672 vol_args = memdup_user(arg, sizeof(*vol_args));
1673 if (IS_ERR(vol_args))
1674 return PTR_ERR(vol_args);
1675 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1676
1677 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1678 vol_args->fd, subvol,
1679 NULL, false, NULL);
1680
1681 kfree(vol_args);
1682 return ret;
1683}
1684
1685static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1686 void __user *arg, int subvol)
1687{
1688 struct btrfs_ioctl_vol_args_v2 *vol_args;
1689 int ret;
1690 u64 transid = 0;
1691 u64 *ptr = NULL;
1692 bool readonly = false;
1693 struct btrfs_qgroup_inherit *inherit = NULL;
1694
1695 vol_args = memdup_user(arg, sizeof(*vol_args));
1696 if (IS_ERR(vol_args))
1697 return PTR_ERR(vol_args);
1698 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1699
1700 if (vol_args->flags &
1701 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1702 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1703 ret = -EOPNOTSUPP;
1704 goto out;
1705 }
1706
1707 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1708 ptr = &transid;
1709 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1710 readonly = true;
1711 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1712 if (vol_args->size > PAGE_CACHE_SIZE) {
1713 ret = -EINVAL;
1714 goto out;
1715 }
1716 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1717 if (IS_ERR(inherit)) {
1718 ret = PTR_ERR(inherit);
1719 goto out;
1720 }
1721 }
1722
1723 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1724 vol_args->fd, subvol, ptr,
1725 readonly, inherit);
1726
1727 if (ret == 0 && ptr &&
1728 copy_to_user(arg +
1729 offsetof(struct btrfs_ioctl_vol_args_v2,
1730 transid), ptr, sizeof(*ptr)))
1731 ret = -EFAULT;
1732out:
1733 kfree(vol_args);
1734 kfree(inherit);
1735 return ret;
1736}
1737
1738static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1739 void __user *arg)
1740{
1741 struct inode *inode = file_inode(file);
1742 struct btrfs_root *root = BTRFS_I(inode)->root;
1743 int ret = 0;
1744 u64 flags = 0;
1745
1746 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1747 return -EINVAL;
1748
1749 down_read(&root->fs_info->subvol_sem);
1750 if (btrfs_root_readonly(root))
1751 flags |= BTRFS_SUBVOL_RDONLY;
1752 up_read(&root->fs_info->subvol_sem);
1753
1754 if (copy_to_user(arg, &flags, sizeof(flags)))
1755 ret = -EFAULT;
1756
1757 return ret;
1758}
1759
1760static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1761 void __user *arg)
1762{
1763 struct inode *inode = file_inode(file);
1764 struct btrfs_root *root = BTRFS_I(inode)->root;
1765 struct btrfs_trans_handle *trans;
1766 u64 root_flags;
1767 u64 flags;
1768 int ret = 0;
1769
1770 if (!inode_owner_or_capable(inode))
1771 return -EPERM;
1772
1773 ret = mnt_want_write_file(file);
1774 if (ret)
1775 goto out;
1776
1777 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1778 ret = -EINVAL;
1779 goto out_drop_write;
1780 }
1781
1782 if (copy_from_user(&flags, arg, sizeof(flags))) {
1783 ret = -EFAULT;
1784 goto out_drop_write;
1785 }
1786
1787 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1788 ret = -EINVAL;
1789 goto out_drop_write;
1790 }
1791
1792 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1793 ret = -EOPNOTSUPP;
1794 goto out_drop_write;
1795 }
1796
1797 down_write(&root->fs_info->subvol_sem);
1798
1799 /* nothing to do */
1800 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1801 goto out_drop_sem;
1802
1803 root_flags = btrfs_root_flags(&root->root_item);
1804 if (flags & BTRFS_SUBVOL_RDONLY) {
1805 btrfs_set_root_flags(&root->root_item,
1806 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1807 } else {
1808 /*
1809 * Block RO -> RW transition if this subvolume is involved in
1810 * send
1811 */
1812 spin_lock(&root->root_item_lock);
1813 if (root->send_in_progress == 0) {
1814 btrfs_set_root_flags(&root->root_item,
1815 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1816 spin_unlock(&root->root_item_lock);
1817 } else {
1818 spin_unlock(&root->root_item_lock);
1819 btrfs_warn(root->fs_info,
1820 "Attempt to set subvolume %llu read-write during send",
1821 root->root_key.objectid);
1822 ret = -EPERM;
1823 goto out_drop_sem;
1824 }
1825 }
1826
1827 trans = btrfs_start_transaction(root, 1);
1828 if (IS_ERR(trans)) {
1829 ret = PTR_ERR(trans);
1830 goto out_reset;
1831 }
1832
1833 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1834 &root->root_key, &root->root_item);
1835
1836 btrfs_commit_transaction(trans, root);
1837out_reset:
1838 if (ret)
1839 btrfs_set_root_flags(&root->root_item, root_flags);
1840out_drop_sem:
1841 up_write(&root->fs_info->subvol_sem);
1842out_drop_write:
1843 mnt_drop_write_file(file);
1844out:
1845 return ret;
1846}
1847
1848/*
1849 * helper to check if the subvolume references other subvolumes
1850 */
1851static noinline int may_destroy_subvol(struct btrfs_root *root)
1852{
1853 struct btrfs_path *path;
1854 struct btrfs_dir_item *di;
1855 struct btrfs_key key;
1856 u64 dir_id;
1857 int ret;
1858
1859 path = btrfs_alloc_path();
1860 if (!path)
1861 return -ENOMEM;
1862
1863 /* Make sure this root isn't set as the default subvol */
1864 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
1865 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
1866 dir_id, "default", 7, 0);
1867 if (di && !IS_ERR(di)) {
1868 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1869 if (key.objectid == root->root_key.objectid) {
1870 ret = -EPERM;
1871 btrfs_err(root->fs_info, "deleting default subvolume "
1872 "%llu is not allowed", key.objectid);
1873 goto out;
1874 }
1875 btrfs_release_path(path);
1876 }
1877
1878 key.objectid = root->root_key.objectid;
1879 key.type = BTRFS_ROOT_REF_KEY;
1880 key.offset = (u64)-1;
1881
1882 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1883 &key, path, 0, 0);
1884 if (ret < 0)
1885 goto out;
1886 BUG_ON(ret == 0);
1887
1888 ret = 0;
1889 if (path->slots[0] > 0) {
1890 path->slots[0]--;
1891 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1892 if (key.objectid == root->root_key.objectid &&
1893 key.type == BTRFS_ROOT_REF_KEY)
1894 ret = -ENOTEMPTY;
1895 }
1896out:
1897 btrfs_free_path(path);
1898 return ret;
1899}
1900
1901static noinline int key_in_sk(struct btrfs_key *key,
1902 struct btrfs_ioctl_search_key *sk)
1903{
1904 struct btrfs_key test;
1905 int ret;
1906
1907 test.objectid = sk->min_objectid;
1908 test.type = sk->min_type;
1909 test.offset = sk->min_offset;
1910
1911 ret = btrfs_comp_cpu_keys(key, &test);
1912 if (ret < 0)
1913 return 0;
1914
1915 test.objectid = sk->max_objectid;
1916 test.type = sk->max_type;
1917 test.offset = sk->max_offset;
1918
1919 ret = btrfs_comp_cpu_keys(key, &test);
1920 if (ret > 0)
1921 return 0;
1922 return 1;
1923}
1924
1925static noinline int copy_to_sk(struct btrfs_root *root,
1926 struct btrfs_path *path,
1927 struct btrfs_key *key,
1928 struct btrfs_ioctl_search_key *sk,
1929 char *buf,
1930 unsigned long *sk_offset,
1931 int *num_found)
1932{
1933 u64 found_transid;
1934 struct extent_buffer *leaf;
1935 struct btrfs_ioctl_search_header sh;
1936 unsigned long item_off;
1937 unsigned long item_len;
1938 int nritems;
1939 int i;
1940 int slot;
1941 int ret = 0;
1942
1943 leaf = path->nodes[0];
1944 slot = path->slots[0];
1945 nritems = btrfs_header_nritems(leaf);
1946
1947 if (btrfs_header_generation(leaf) > sk->max_transid) {
1948 i = nritems;
1949 goto advance_key;
1950 }
1951 found_transid = btrfs_header_generation(leaf);
1952
1953 for (i = slot; i < nritems; i++) {
1954 item_off = btrfs_item_ptr_offset(leaf, i);
1955 item_len = btrfs_item_size_nr(leaf, i);
1956
1957 btrfs_item_key_to_cpu(leaf, key, i);
1958 if (!key_in_sk(key, sk))
1959 continue;
1960
1961 if (sizeof(sh) + item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1962 item_len = 0;
1963
1964 if (sizeof(sh) + item_len + *sk_offset >
1965 BTRFS_SEARCH_ARGS_BUFSIZE) {
1966 ret = 1;
1967 goto overflow;
1968 }
1969
1970 sh.objectid = key->objectid;
1971 sh.offset = key->offset;
1972 sh.type = key->type;
1973 sh.len = item_len;
1974 sh.transid = found_transid;
1975
1976 /* copy search result header */
1977 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1978 *sk_offset += sizeof(sh);
1979
1980 if (item_len) {
1981 char *p = buf + *sk_offset;
1982 /* copy the item */
1983 read_extent_buffer(leaf, p,
1984 item_off, item_len);
1985 *sk_offset += item_len;
1986 }
1987 (*num_found)++;
1988
1989 if (*num_found >= sk->nr_items)
1990 break;
1991 }
1992advance_key:
1993 ret = 0;
1994 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1995 key->offset++;
1996 else if (key->type < (u8)-1 && key->type < sk->max_type) {
1997 key->offset = 0;
1998 key->type++;
1999 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
2000 key->offset = 0;
2001 key->type = 0;
2002 key->objectid++;
2003 } else
2004 ret = 1;
2005overflow:
2006 return ret;
2007}
2008
2009static noinline int search_ioctl(struct inode *inode,
2010 struct btrfs_ioctl_search_args *args)
2011{
2012 struct btrfs_root *root;
2013 struct btrfs_key key;
2014 struct btrfs_path *path;
2015 struct btrfs_ioctl_search_key *sk = &args->key;
2016 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
2017 int ret;
2018 int num_found = 0;
2019 unsigned long sk_offset = 0;
2020
2021 path = btrfs_alloc_path();
2022 if (!path)
2023 return -ENOMEM;
2024
2025 if (sk->tree_id == 0) {
2026 /* search the root of the inode that was passed */
2027 root = BTRFS_I(inode)->root;
2028 } else {
2029 key.objectid = sk->tree_id;
2030 key.type = BTRFS_ROOT_ITEM_KEY;
2031 key.offset = (u64)-1;
2032 root = btrfs_read_fs_root_no_name(info, &key);
2033 if (IS_ERR(root)) {
2034 printk(KERN_ERR "BTRFS: could not find root %llu\n",
2035 sk->tree_id);
2036 btrfs_free_path(path);
2037 return -ENOENT;
2038 }
2039 }
2040
2041 key.objectid = sk->min_objectid;
2042 key.type = sk->min_type;
2043 key.offset = sk->min_offset;
2044
2045 path->keep_locks = 1;
2046
2047 while (1) {
2048 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2049 if (ret != 0) {
2050 if (ret > 0)
2051 ret = 0;
2052 goto err;
2053 }
2054 ret = copy_to_sk(root, path, &key, sk, args->buf,
2055 &sk_offset, &num_found);
2056 btrfs_release_path(path);
2057 if (ret || num_found >= sk->nr_items)
2058 break;
2059
2060 }
2061 ret = 0;
2062err:
2063 sk->nr_items = num_found;
2064 btrfs_free_path(path);
2065 return ret;
2066}
2067
2068static noinline int btrfs_ioctl_tree_search(struct file *file,
2069 void __user *argp)
2070{
2071 struct btrfs_ioctl_search_args *args;
2072 struct inode *inode;
2073 int ret;
2074
2075 if (!capable(CAP_SYS_ADMIN))
2076 return -EPERM;
2077
2078 args = memdup_user(argp, sizeof(*args));
2079 if (IS_ERR(args))
2080 return PTR_ERR(args);
2081
2082 inode = file_inode(file);
2083 ret = search_ioctl(inode, args);
2084 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2085 ret = -EFAULT;
2086 kfree(args);
2087 return ret;
2088}
2089
2090/*
2091 * Search INODE_REFs to identify path name of 'dirid' directory
2092 * in a 'tree_id' tree. and sets path name to 'name'.
2093 */
2094static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2095 u64 tree_id, u64 dirid, char *name)
2096{
2097 struct btrfs_root *root;
2098 struct btrfs_key key;
2099 char *ptr;
2100 int ret = -1;
2101 int slot;
2102 int len;
2103 int total_len = 0;
2104 struct btrfs_inode_ref *iref;
2105 struct extent_buffer *l;
2106 struct btrfs_path *path;
2107
2108 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2109 name[0]='\0';
2110 return 0;
2111 }
2112
2113 path = btrfs_alloc_path();
2114 if (!path)
2115 return -ENOMEM;
2116
2117 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2118
2119 key.objectid = tree_id;
2120 key.type = BTRFS_ROOT_ITEM_KEY;
2121 key.offset = (u64)-1;
2122 root = btrfs_read_fs_root_no_name(info, &key);
2123 if (IS_ERR(root)) {
2124 printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id);
2125 ret = -ENOENT;
2126 goto out;
2127 }
2128
2129 key.objectid = dirid;
2130 key.type = BTRFS_INODE_REF_KEY;
2131 key.offset = (u64)-1;
2132
2133 while (1) {
2134 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2135 if (ret < 0)
2136 goto out;
2137 else if (ret > 0) {
2138 ret = btrfs_previous_item(root, path, dirid,
2139 BTRFS_INODE_REF_KEY);
2140 if (ret < 0)
2141 goto out;
2142 else if (ret > 0) {
2143 ret = -ENOENT;
2144 goto out;
2145 }
2146 }
2147
2148 l = path->nodes[0];
2149 slot = path->slots[0];
2150 btrfs_item_key_to_cpu(l, &key, slot);
2151
2152 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2153 len = btrfs_inode_ref_name_len(l, iref);
2154 ptr -= len + 1;
2155 total_len += len + 1;
2156 if (ptr < name) {
2157 ret = -ENAMETOOLONG;
2158 goto out;
2159 }
2160
2161 *(ptr + len) = '/';
2162 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2163
2164 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2165 break;
2166
2167 btrfs_release_path(path);
2168 key.objectid = key.offset;
2169 key.offset = (u64)-1;
2170 dirid = key.objectid;
2171 }
2172 memmove(name, ptr, total_len);
2173 name[total_len] = '\0';
2174 ret = 0;
2175out:
2176 btrfs_free_path(path);
2177 return ret;
2178}
2179
2180static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2181 void __user *argp)
2182{
2183 struct btrfs_ioctl_ino_lookup_args *args;
2184 struct inode *inode;
2185 int ret;
2186
2187 if (!capable(CAP_SYS_ADMIN))
2188 return -EPERM;
2189
2190 args = memdup_user(argp, sizeof(*args));
2191 if (IS_ERR(args))
2192 return PTR_ERR(args);
2193
2194 inode = file_inode(file);
2195
2196 if (args->treeid == 0)
2197 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2198
2199 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2200 args->treeid, args->objectid,
2201 args->name);
2202
2203 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2204 ret = -EFAULT;
2205
2206 kfree(args);
2207 return ret;
2208}
2209
2210static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2211 void __user *arg)
2212{
2213 struct dentry *parent = file->f_path.dentry;
2214 struct dentry *dentry;
2215 struct inode *dir = parent->d_inode;
2216 struct inode *inode;
2217 struct btrfs_root *root = BTRFS_I(dir)->root;
2218 struct btrfs_root *dest = NULL;
2219 struct btrfs_ioctl_vol_args *vol_args;
2220 struct btrfs_trans_handle *trans;
2221 struct btrfs_block_rsv block_rsv;
2222 u64 qgroup_reserved;
2223 int namelen;
2224 int ret;
2225 int err = 0;
2226
2227 vol_args = memdup_user(arg, sizeof(*vol_args));
2228 if (IS_ERR(vol_args))
2229 return PTR_ERR(vol_args);
2230
2231 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2232 namelen = strlen(vol_args->name);
2233 if (strchr(vol_args->name, '/') ||
2234 strncmp(vol_args->name, "..", namelen) == 0) {
2235 err = -EINVAL;
2236 goto out;
2237 }
2238
2239 err = mnt_want_write_file(file);
2240 if (err)
2241 goto out;
2242
2243 err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
2244 if (err == -EINTR)
2245 goto out_drop_write;
2246 dentry = lookup_one_len(vol_args->name, parent, namelen);
2247 if (IS_ERR(dentry)) {
2248 err = PTR_ERR(dentry);
2249 goto out_unlock_dir;
2250 }
2251
2252 if (!dentry->d_inode) {
2253 err = -ENOENT;
2254 goto out_dput;
2255 }
2256
2257 inode = dentry->d_inode;
2258 dest = BTRFS_I(inode)->root;
2259 if (!capable(CAP_SYS_ADMIN)) {
2260 /*
2261 * Regular user. Only allow this with a special mount
2262 * option, when the user has write+exec access to the
2263 * subvol root, and when rmdir(2) would have been
2264 * allowed.
2265 *
2266 * Note that this is _not_ check that the subvol is
2267 * empty or doesn't contain data that we wouldn't
2268 * otherwise be able to delete.
2269 *
2270 * Users who want to delete empty subvols should try
2271 * rmdir(2).
2272 */
2273 err = -EPERM;
2274 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2275 goto out_dput;
2276
2277 /*
2278 * Do not allow deletion if the parent dir is the same
2279 * as the dir to be deleted. That means the ioctl
2280 * must be called on the dentry referencing the root
2281 * of the subvol, not a random directory contained
2282 * within it.
2283 */
2284 err = -EINVAL;
2285 if (root == dest)
2286 goto out_dput;
2287
2288 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2289 if (err)
2290 goto out_dput;
2291 }
2292
2293 /* check if subvolume may be deleted by a user */
2294 err = btrfs_may_delete(dir, dentry, 1);
2295 if (err)
2296 goto out_dput;
2297
2298 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2299 err = -EINVAL;
2300 goto out_dput;
2301 }
2302
2303 mutex_lock(&inode->i_mutex);
2304 err = d_invalidate(dentry);
2305 if (err)
2306 goto out_unlock;
2307
2308 down_write(&root->fs_info->subvol_sem);
2309
2310 err = may_destroy_subvol(dest);
2311 if (err)
2312 goto out_up_write;
2313
2314 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2315 /*
2316 * One for dir inode, two for dir entries, two for root
2317 * ref/backref.
2318 */
2319 err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2320 5, &qgroup_reserved, true);
2321 if (err)
2322 goto out_up_write;
2323
2324 trans = btrfs_start_transaction(root, 0);
2325 if (IS_ERR(trans)) {
2326 err = PTR_ERR(trans);
2327 goto out_release;
2328 }
2329 trans->block_rsv = &block_rsv;
2330 trans->bytes_reserved = block_rsv.size;
2331
2332 ret = btrfs_unlink_subvol(trans, root, dir,
2333 dest->root_key.objectid,
2334 dentry->d_name.name,
2335 dentry->d_name.len);
2336 if (ret) {
2337 err = ret;
2338 btrfs_abort_transaction(trans, root, ret);
2339 goto out_end_trans;
2340 }
2341
2342 btrfs_record_root_in_trans(trans, dest);
2343
2344 memset(&dest->root_item.drop_progress, 0,
2345 sizeof(dest->root_item.drop_progress));
2346 dest->root_item.drop_level = 0;
2347 btrfs_set_root_refs(&dest->root_item, 0);
2348
2349 if (!xchg(&dest->orphan_item_inserted, 1)) {
2350 ret = btrfs_insert_orphan_item(trans,
2351 root->fs_info->tree_root,
2352 dest->root_key.objectid);
2353 if (ret) {
2354 btrfs_abort_transaction(trans, root, ret);
2355 err = ret;
2356 goto out_end_trans;
2357 }
2358 }
2359
2360 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2361 dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
2362 dest->root_key.objectid);
2363 if (ret && ret != -ENOENT) {
2364 btrfs_abort_transaction(trans, root, ret);
2365 err = ret;
2366 goto out_end_trans;
2367 }
2368 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
2369 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2370 dest->root_item.received_uuid,
2371 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
2372 dest->root_key.objectid);
2373 if (ret && ret != -ENOENT) {
2374 btrfs_abort_transaction(trans, root, ret);
2375 err = ret;
2376 goto out_end_trans;
2377 }
2378 }
2379
2380out_end_trans:
2381 trans->block_rsv = NULL;
2382 trans->bytes_reserved = 0;
2383 ret = btrfs_end_transaction(trans, root);
2384 if (ret && !err)
2385 err = ret;
2386 inode->i_flags |= S_DEAD;
2387out_release:
2388 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2389out_up_write:
2390 up_write(&root->fs_info->subvol_sem);
2391out_unlock:
2392 mutex_unlock(&inode->i_mutex);
2393 if (!err) {
2394 shrink_dcache_sb(root->fs_info->sb);
2395 btrfs_invalidate_inodes(dest);
2396 d_delete(dentry);
2397
2398 /* the last ref */
2399 if (dest->cache_inode) {
2400 iput(dest->cache_inode);
2401 dest->cache_inode = NULL;
2402 }
2403 }
2404out_dput:
2405 dput(dentry);
2406out_unlock_dir:
2407 mutex_unlock(&dir->i_mutex);
2408out_drop_write:
2409 mnt_drop_write_file(file);
2410out:
2411 kfree(vol_args);
2412 return err;
2413}
2414
2415static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2416{
2417 struct inode *inode = file_inode(file);
2418 struct btrfs_root *root = BTRFS_I(inode)->root;
2419 struct btrfs_ioctl_defrag_range_args *range;
2420 int ret;
2421
2422 ret = mnt_want_write_file(file);
2423 if (ret)
2424 return ret;
2425
2426 if (btrfs_root_readonly(root)) {
2427 ret = -EROFS;
2428 goto out;
2429 }
2430
2431 switch (inode->i_mode & S_IFMT) {
2432 case S_IFDIR:
2433 if (!capable(CAP_SYS_ADMIN)) {
2434 ret = -EPERM;
2435 goto out;
2436 }
2437 ret = btrfs_defrag_root(root);
2438 if (ret)
2439 goto out;
2440 ret = btrfs_defrag_root(root->fs_info->extent_root);
2441 break;
2442 case S_IFREG:
2443 if (!(file->f_mode & FMODE_WRITE)) {
2444 ret = -EINVAL;
2445 goto out;
2446 }
2447
2448 range = kzalloc(sizeof(*range), GFP_KERNEL);
2449 if (!range) {
2450 ret = -ENOMEM;
2451 goto out;
2452 }
2453
2454 if (argp) {
2455 if (copy_from_user(range, argp,
2456 sizeof(*range))) {
2457 ret = -EFAULT;
2458 kfree(range);
2459 goto out;
2460 }
2461 /* compression requires us to start the IO */
2462 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2463 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2464 range->extent_thresh = (u32)-1;
2465 }
2466 } else {
2467 /* the rest are all set to zero by kzalloc */
2468 range->len = (u64)-1;
2469 }
2470 ret = btrfs_defrag_file(file_inode(file), file,
2471 range, 0, 0);
2472 if (ret > 0)
2473 ret = 0;
2474 kfree(range);
2475 break;
2476 default:
2477 ret = -EINVAL;
2478 }
2479out:
2480 mnt_drop_write_file(file);
2481 return ret;
2482}
2483
2484static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2485{
2486 struct btrfs_ioctl_vol_args *vol_args;
2487 int ret;
2488
2489 if (!capable(CAP_SYS_ADMIN))
2490 return -EPERM;
2491
2492 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2493 1)) {
2494 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2495 }
2496
2497 mutex_lock(&root->fs_info->volume_mutex);
2498 vol_args = memdup_user(arg, sizeof(*vol_args));
2499 if (IS_ERR(vol_args)) {
2500 ret = PTR_ERR(vol_args);
2501 goto out;
2502 }
2503
2504 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2505 ret = btrfs_init_new_device(root, vol_args->name);
2506
2507 kfree(vol_args);
2508out:
2509 mutex_unlock(&root->fs_info->volume_mutex);
2510 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2511 return ret;
2512}
2513
2514static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2515{
2516 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
2517 struct btrfs_ioctl_vol_args *vol_args;
2518 int ret;
2519
2520 if (!capable(CAP_SYS_ADMIN))
2521 return -EPERM;
2522
2523 ret = mnt_want_write_file(file);
2524 if (ret)
2525 return ret;
2526
2527 vol_args = memdup_user(arg, sizeof(*vol_args));
2528 if (IS_ERR(vol_args)) {
2529 ret = PTR_ERR(vol_args);
2530 goto out;
2531 }
2532
2533 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2534
2535 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2536 1)) {
2537 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2538 goto out;
2539 }
2540
2541 mutex_lock(&root->fs_info->volume_mutex);
2542 ret = btrfs_rm_device(root, vol_args->name);
2543 mutex_unlock(&root->fs_info->volume_mutex);
2544 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2545
2546out:
2547 kfree(vol_args);
2548 mnt_drop_write_file(file);
2549 return ret;
2550}
2551
2552static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2553{
2554 struct btrfs_ioctl_fs_info_args *fi_args;
2555 struct btrfs_device *device;
2556 struct btrfs_device *next;
2557 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2558 int ret = 0;
2559
2560 if (!capable(CAP_SYS_ADMIN))
2561 return -EPERM;
2562
2563 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2564 if (!fi_args)
2565 return -ENOMEM;
2566
2567 mutex_lock(&fs_devices->device_list_mutex);
2568 fi_args->num_devices = fs_devices->num_devices;
2569 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2570
2571 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2572 if (device->devid > fi_args->max_id)
2573 fi_args->max_id = device->devid;
2574 }
2575 mutex_unlock(&fs_devices->device_list_mutex);
2576
2577 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2578 ret = -EFAULT;
2579
2580 kfree(fi_args);
2581 return ret;
2582}
2583
2584static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2585{
2586 struct btrfs_ioctl_dev_info_args *di_args;
2587 struct btrfs_device *dev;
2588 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2589 int ret = 0;
2590 char *s_uuid = NULL;
2591
2592 if (!capable(CAP_SYS_ADMIN))
2593 return -EPERM;
2594
2595 di_args = memdup_user(arg, sizeof(*di_args));
2596 if (IS_ERR(di_args))
2597 return PTR_ERR(di_args);
2598
2599 if (!btrfs_is_empty_uuid(di_args->uuid))
2600 s_uuid = di_args->uuid;
2601
2602 mutex_lock(&fs_devices->device_list_mutex);
2603 dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2604
2605 if (!dev) {
2606 ret = -ENODEV;
2607 goto out;
2608 }
2609
2610 di_args->devid = dev->devid;
2611 di_args->bytes_used = dev->bytes_used;
2612 di_args->total_bytes = dev->total_bytes;
2613 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2614 if (dev->name) {
2615 struct rcu_string *name;
2616
2617 rcu_read_lock();
2618 name = rcu_dereference(dev->name);
2619 strncpy(di_args->path, name->str, sizeof(di_args->path));
2620 rcu_read_unlock();
2621 di_args->path[sizeof(di_args->path) - 1] = 0;
2622 } else {
2623 di_args->path[0] = '\0';
2624 }
2625
2626out:
2627 mutex_unlock(&fs_devices->device_list_mutex);
2628 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2629 ret = -EFAULT;
2630
2631 kfree(di_args);
2632 return ret;
2633}
2634
2635static struct page *extent_same_get_page(struct inode *inode, u64 off)
2636{
2637 struct page *page;
2638 pgoff_t index;
2639 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
2640
2641 index = off >> PAGE_CACHE_SHIFT;
2642
2643 page = grab_cache_page(inode->i_mapping, index);
2644 if (!page)
2645 return NULL;
2646
2647 if (!PageUptodate(page)) {
2648 if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
2649 0))
2650 return NULL;
2651 lock_page(page);
2652 if (!PageUptodate(page)) {
2653 unlock_page(page);
2654 page_cache_release(page);
2655 return NULL;
2656 }
2657 }
2658 unlock_page(page);
2659
2660 return page;
2661}
2662
2663static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
2664{
2665 /* do any pending delalloc/csum calc on src, one way or
2666 another, and lock file content */
2667 while (1) {
2668 struct btrfs_ordered_extent *ordered;
2669 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2670 ordered = btrfs_lookup_first_ordered_extent(inode,
2671 off + len - 1);
2672 if (!ordered &&
2673 !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2674 off + len - 1, EXTENT_DELALLOC, 0, NULL))
2675 break;
2676 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2677 if (ordered)
2678 btrfs_put_ordered_extent(ordered);
2679 btrfs_wait_ordered_range(inode, off, len);
2680 }
2681}
2682
2683static void btrfs_double_unlock(struct inode *inode1, u64 loff1,
2684 struct inode *inode2, u64 loff2, u64 len)
2685{
2686 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
2687 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
2688
2689 mutex_unlock(&inode1->i_mutex);
2690 mutex_unlock(&inode2->i_mutex);
2691}
2692
2693static void btrfs_double_lock(struct inode *inode1, u64 loff1,
2694 struct inode *inode2, u64 loff2, u64 len)
2695{
2696 if (inode1 < inode2) {
2697 swap(inode1, inode2);
2698 swap(loff1, loff2);
2699 }
2700
2701 mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
2702 lock_extent_range(inode1, loff1, len);
2703 if (inode1 != inode2) {
2704 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
2705 lock_extent_range(inode2, loff2, len);
2706 }
2707}
2708
2709static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
2710 u64 dst_loff, u64 len)
2711{
2712 int ret = 0;
2713 struct page *src_page, *dst_page;
2714 unsigned int cmp_len = PAGE_CACHE_SIZE;
2715 void *addr, *dst_addr;
2716
2717 while (len) {
2718 if (len < PAGE_CACHE_SIZE)
2719 cmp_len = len;
2720
2721 src_page = extent_same_get_page(src, loff);
2722 if (!src_page)
2723 return -EINVAL;
2724 dst_page = extent_same_get_page(dst, dst_loff);
2725 if (!dst_page) {
2726 page_cache_release(src_page);
2727 return -EINVAL;
2728 }
2729 addr = kmap_atomic(src_page);
2730 dst_addr = kmap_atomic(dst_page);
2731
2732 flush_dcache_page(src_page);
2733 flush_dcache_page(dst_page);
2734
2735 if (memcmp(addr, dst_addr, cmp_len))
2736 ret = BTRFS_SAME_DATA_DIFFERS;
2737
2738 kunmap_atomic(addr);
2739 kunmap_atomic(dst_addr);
2740 page_cache_release(src_page);
2741 page_cache_release(dst_page);
2742
2743 if (ret)
2744 break;
2745
2746 loff += cmp_len;
2747 dst_loff += cmp_len;
2748 len -= cmp_len;
2749 }
2750
2751 return ret;
2752}
2753
2754static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len)
2755{
2756 u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
2757
2758 if (off + len > inode->i_size || off + len < off)
2759 return -EINVAL;
2760 /* Check that we are block aligned - btrfs_clone() requires this */
2761 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
2762 return -EINVAL;
2763
2764 return 0;
2765}
2766
2767static int btrfs_extent_same(struct inode *src, u64 loff, u64 len,
2768 struct inode *dst, u64 dst_loff)
2769{
2770 int ret;
2771
2772 /*
2773 * btrfs_clone() can't handle extents in the same file
2774 * yet. Once that works, we can drop this check and replace it
2775 * with a check for the same inode, but overlapping extents.
2776 */
2777 if (src == dst)
2778 return -EINVAL;
2779
2780 btrfs_double_lock(src, loff, dst, dst_loff, len);
2781
2782 ret = extent_same_check_offsets(src, loff, len);
2783 if (ret)
2784 goto out_unlock;
2785
2786 ret = extent_same_check_offsets(dst, dst_loff, len);
2787 if (ret)
2788 goto out_unlock;
2789
2790 /* don't make the dst file partly checksummed */
2791 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2792 (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
2793 ret = -EINVAL;
2794 goto out_unlock;
2795 }
2796
2797 ret = btrfs_cmp_data(src, loff, dst, dst_loff, len);
2798 if (ret == 0)
2799 ret = btrfs_clone(src, dst, loff, len, len, dst_loff);
2800
2801out_unlock:
2802 btrfs_double_unlock(src, loff, dst, dst_loff, len);
2803
2804 return ret;
2805}
2806
2807#define BTRFS_MAX_DEDUPE_LEN (16 * 1024 * 1024)
2808
2809static long btrfs_ioctl_file_extent_same(struct file *file,
2810 struct btrfs_ioctl_same_args __user *argp)
2811{
2812 struct btrfs_ioctl_same_args *same;
2813 struct btrfs_ioctl_same_extent_info *info;
2814 struct inode *src = file_inode(file);
2815 u64 off;
2816 u64 len;
2817 int i;
2818 int ret;
2819 unsigned long size;
2820 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
2821 bool is_admin = capable(CAP_SYS_ADMIN);
2822 u16 count;
2823
2824 if (!(file->f_mode & FMODE_READ))
2825 return -EINVAL;
2826
2827 ret = mnt_want_write_file(file);
2828 if (ret)
2829 return ret;
2830
2831 if (get_user(count, &argp->dest_count)) {
2832 ret = -EFAULT;
2833 goto out;
2834 }
2835
2836 size = offsetof(struct btrfs_ioctl_same_args __user, info[count]);
2837
2838 same = memdup_user(argp, size);
2839
2840 if (IS_ERR(same)) {
2841 ret = PTR_ERR(same);
2842 goto out;
2843 }
2844
2845 off = same->logical_offset;
2846 len = same->length;
2847
2848 /*
2849 * Limit the total length we will dedupe for each operation.
2850 * This is intended to bound the total time spent in this
2851 * ioctl to something sane.
2852 */
2853 if (len > BTRFS_MAX_DEDUPE_LEN)
2854 len = BTRFS_MAX_DEDUPE_LEN;
2855
2856 if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
2857 /*
2858 * Btrfs does not support blocksize < page_size. As a
2859 * result, btrfs_cmp_data() won't correctly handle
2860 * this situation without an update.
2861 */
2862 ret = -EINVAL;
2863 goto out;
2864 }
2865
2866 ret = -EISDIR;
2867 if (S_ISDIR(src->i_mode))
2868 goto out;
2869
2870 ret = -EACCES;
2871 if (!S_ISREG(src->i_mode))
2872 goto out;
2873
2874 /* pre-format output fields to sane values */
2875 for (i = 0; i < count; i++) {
2876 same->info[i].bytes_deduped = 0ULL;
2877 same->info[i].status = 0;
2878 }
2879
2880 for (i = 0, info = same->info; i < count; i++, info++) {
2881 struct inode *dst;
2882 struct fd dst_file = fdget(info->fd);
2883 if (!dst_file.file) {
2884 info->status = -EBADF;
2885 continue;
2886 }
2887 dst = file_inode(dst_file.file);
2888
2889 if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) {
2890 info->status = -EINVAL;
2891 } else if (file->f_path.mnt != dst_file.file->f_path.mnt) {
2892 info->status = -EXDEV;
2893 } else if (S_ISDIR(dst->i_mode)) {
2894 info->status = -EISDIR;
2895 } else if (!S_ISREG(dst->i_mode)) {
2896 info->status = -EACCES;
2897 } else {
2898 info->status = btrfs_extent_same(src, off, len, dst,
2899 info->logical_offset);
2900 if (info->status == 0)
2901 info->bytes_deduped += len;
2902 }
2903 fdput(dst_file);
2904 }
2905
2906 ret = copy_to_user(argp, same, size);
2907 if (ret)
2908 ret = -EFAULT;
2909
2910out:
2911 mnt_drop_write_file(file);
2912 return ret;
2913}
2914
2915/**
2916 * btrfs_clone() - clone a range from inode file to another
2917 *
2918 * @src: Inode to clone from
2919 * @inode: Inode to clone to
2920 * @off: Offset within source to start clone from
2921 * @olen: Original length, passed by user, of range to clone
2922 * @olen_aligned: Block-aligned value of olen, extent_same uses
2923 * identical values here
2924 * @destoff: Offset within @inode to start clone
2925 */
2926static int btrfs_clone(struct inode *src, struct inode *inode,
2927 u64 off, u64 olen, u64 olen_aligned, u64 destoff)
2928{
2929 struct btrfs_root *root = BTRFS_I(inode)->root;
2930 struct btrfs_path *path = NULL;
2931 struct extent_buffer *leaf;
2932 struct btrfs_trans_handle *trans;
2933 char *buf = NULL;
2934 struct btrfs_key key;
2935 u32 nritems;
2936 int slot;
2937 int ret;
2938 u64 len = olen_aligned;
2939
2940 ret = -ENOMEM;
2941 buf = vmalloc(btrfs_level_size(root, 0));
2942 if (!buf)
2943 return ret;
2944
2945 path = btrfs_alloc_path();
2946 if (!path) {
2947 vfree(buf);
2948 return ret;
2949 }
2950
2951 path->reada = 2;
2952 /* clone data */
2953 key.objectid = btrfs_ino(src);
2954 key.type = BTRFS_EXTENT_DATA_KEY;
2955 key.offset = 0;
2956
2957 while (1) {
2958 /*
2959 * note the key will change type as we walk through the
2960 * tree.
2961 */
2962 path->leave_spinning = 1;
2963 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
2964 0, 0);
2965 if (ret < 0)
2966 goto out;
2967
2968 nritems = btrfs_header_nritems(path->nodes[0]);
2969process_slot:
2970 if (path->slots[0] >= nritems) {
2971 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
2972 if (ret < 0)
2973 goto out;
2974 if (ret > 0)
2975 break;
2976 nritems = btrfs_header_nritems(path->nodes[0]);
2977 }
2978 leaf = path->nodes[0];
2979 slot = path->slots[0];
2980
2981 btrfs_item_key_to_cpu(leaf, &key, slot);
2982 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2983 key.objectid != btrfs_ino(src))
2984 break;
2985
2986 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2987 struct btrfs_file_extent_item *extent;
2988 int type;
2989 u32 size;
2990 struct btrfs_key new_key;
2991 u64 disko = 0, diskl = 0;
2992 u64 datao = 0, datal = 0;
2993 u8 comp;
2994 u64 endoff;
2995
2996 extent = btrfs_item_ptr(leaf, slot,
2997 struct btrfs_file_extent_item);
2998 comp = btrfs_file_extent_compression(leaf, extent);
2999 type = btrfs_file_extent_type(leaf, extent);
3000 if (type == BTRFS_FILE_EXTENT_REG ||
3001 type == BTRFS_FILE_EXTENT_PREALLOC) {
3002 disko = btrfs_file_extent_disk_bytenr(leaf,
3003 extent);
3004 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3005 extent);
3006 datao = btrfs_file_extent_offset(leaf, extent);
3007 datal = btrfs_file_extent_num_bytes(leaf,
3008 extent);
3009 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3010 /* take upper bound, may be compressed */
3011 datal = btrfs_file_extent_ram_bytes(leaf,
3012 extent);
3013 }
3014
3015 if (key.offset + datal <= off ||
3016 key.offset >= off + len - 1) {
3017 path->slots[0]++;
3018 goto process_slot;
3019 }
3020
3021 size = btrfs_item_size_nr(leaf, slot);
3022 read_extent_buffer(leaf, buf,
3023 btrfs_item_ptr_offset(leaf, slot),
3024 size);
3025
3026 btrfs_release_path(path);
3027 path->leave_spinning = 0;
3028
3029 memcpy(&new_key, &key, sizeof(new_key));
3030 new_key.objectid = btrfs_ino(inode);
3031 if (off <= key.offset)
3032 new_key.offset = key.offset + destoff - off;
3033 else
3034 new_key.offset = destoff;
3035
3036 /*
3037 * 1 - adjusting old extent (we may have to split it)
3038 * 1 - add new extent
3039 * 1 - inode update
3040 */
3041 trans = btrfs_start_transaction(root, 3);
3042 if (IS_ERR(trans)) {
3043 ret = PTR_ERR(trans);
3044 goto out;
3045 }
3046
3047 if (type == BTRFS_FILE_EXTENT_REG ||
3048 type == BTRFS_FILE_EXTENT_PREALLOC) {
3049 /*
3050 * a | --- range to clone ---| b
3051 * | ------------- extent ------------- |
3052 */
3053
3054 /* substract range b */
3055 if (key.offset + datal > off + len)
3056 datal = off + len - key.offset;
3057
3058 /* substract range a */
3059 if (off > key.offset) {
3060 datao += off - key.offset;
3061 datal -= off - key.offset;
3062 }
3063
3064 ret = btrfs_drop_extents(trans, root, inode,
3065 new_key.offset,
3066 new_key.offset + datal,
3067 1);
3068 if (ret) {
3069 if (ret != -EOPNOTSUPP)
3070 btrfs_abort_transaction(trans,
3071 root, ret);
3072 btrfs_end_transaction(trans, root);
3073 goto out;
3074 }
3075
3076 ret = btrfs_insert_empty_item(trans, root, path,
3077 &new_key, size);
3078 if (ret) {
3079 btrfs_abort_transaction(trans, root,
3080 ret);
3081 btrfs_end_transaction(trans, root);
3082 goto out;
3083 }
3084
3085 leaf = path->nodes[0];
3086 slot = path->slots[0];
3087 write_extent_buffer(leaf, buf,
3088 btrfs_item_ptr_offset(leaf, slot),
3089 size);
3090
3091 extent = btrfs_item_ptr(leaf, slot,
3092 struct btrfs_file_extent_item);
3093
3094 /* disko == 0 means it's a hole */
3095 if (!disko)
3096 datao = 0;
3097
3098 btrfs_set_file_extent_offset(leaf, extent,
3099 datao);
3100 btrfs_set_file_extent_num_bytes(leaf, extent,
3101 datal);
3102 if (disko) {
3103 inode_add_bytes(inode, datal);
3104 ret = btrfs_inc_extent_ref(trans, root,
3105 disko, diskl, 0,
3106 root->root_key.objectid,
3107 btrfs_ino(inode),
3108 new_key.offset - datao,
3109 0);
3110 if (ret) {
3111 btrfs_abort_transaction(trans,
3112 root,
3113 ret);
3114 btrfs_end_transaction(trans,
3115 root);
3116 goto out;
3117
3118 }
3119 }
3120 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3121 u64 skip = 0;
3122 u64 trim = 0;
3123 u64 aligned_end = 0;
3124
3125 if (off > key.offset) {
3126 skip = off - key.offset;
3127 new_key.offset += skip;
3128 }
3129
3130 if (key.offset + datal > off + len)
3131 trim = key.offset + datal - (off + len);
3132
3133 if (comp && (skip || trim)) {
3134 ret = -EINVAL;
3135 btrfs_end_transaction(trans, root);
3136 goto out;
3137 }
3138 size -= skip + trim;
3139 datal -= skip + trim;
3140
3141 aligned_end = ALIGN(new_key.offset + datal,
3142 root->sectorsize);
3143 ret = btrfs_drop_extents(trans, root, inode,
3144 new_key.offset,
3145 aligned_end,
3146 1);
3147 if (ret) {
3148 if (ret != -EOPNOTSUPP)
3149 btrfs_abort_transaction(trans,
3150 root, ret);
3151 btrfs_end_transaction(trans, root);
3152 goto out;
3153 }
3154
3155 ret = btrfs_insert_empty_item(trans, root, path,
3156 &new_key, size);
3157 if (ret) {
3158 btrfs_abort_transaction(trans, root,
3159 ret);
3160 btrfs_end_transaction(trans, root);
3161 goto out;
3162 }
3163
3164 if (skip) {
3165 u32 start =
3166 btrfs_file_extent_calc_inline_size(0);
3167 memmove(buf+start, buf+start+skip,
3168 datal);
3169 }
3170
3171 leaf = path->nodes[0];
3172 slot = path->slots[0];
3173 write_extent_buffer(leaf, buf,
3174 btrfs_item_ptr_offset(leaf, slot),
3175 size);
3176 inode_add_bytes(inode, datal);
3177 }
3178
3179 btrfs_mark_buffer_dirty(leaf);
3180 btrfs_release_path(path);
3181
3182 inode_inc_iversion(inode);
3183 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3184
3185 /*
3186 * we round up to the block size at eof when
3187 * determining which extents to clone above,
3188 * but shouldn't round up the file size
3189 */
3190 endoff = new_key.offset + datal;
3191 if (endoff > destoff+olen)
3192 endoff = destoff+olen;
3193 if (endoff > inode->i_size)
3194 btrfs_i_size_write(inode, endoff);
3195
3196 ret = btrfs_update_inode(trans, root, inode);
3197 if (ret) {
3198 btrfs_abort_transaction(trans, root, ret);
3199 btrfs_end_transaction(trans, root);
3200 goto out;
3201 }
3202 ret = btrfs_end_transaction(trans, root);
3203 }
3204 btrfs_release_path(path);
3205 key.offset++;
3206 }
3207 ret = 0;
3208
3209out:
3210 btrfs_release_path(path);
3211 btrfs_free_path(path);
3212 vfree(buf);
3213 return ret;
3214}
3215
3216static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
3217 u64 off, u64 olen, u64 destoff)
3218{
3219 struct inode *inode = file_inode(file);
3220 struct btrfs_root *root = BTRFS_I(inode)->root;
3221 struct fd src_file;
3222 struct inode *src;
3223 int ret;
3224 u64 len = olen;
3225 u64 bs = root->fs_info->sb->s_blocksize;
3226 int same_inode = 0;
3227
3228 /*
3229 * TODO:
3230 * - split compressed inline extents. annoying: we need to
3231 * decompress into destination's address_space (the file offset
3232 * may change, so source mapping won't do), then recompress (or
3233 * otherwise reinsert) a subrange.
3234 *
3235 * - split destination inode's inline extents. The inline extents can
3236 * be either compressed or non-compressed.
3237 */
3238
3239 /* the destination must be opened for writing */
3240 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
3241 return -EINVAL;
3242
3243 if (btrfs_root_readonly(root))
3244 return -EROFS;
3245
3246 ret = mnt_want_write_file(file);
3247 if (ret)
3248 return ret;
3249
3250 src_file = fdget(srcfd);
3251 if (!src_file.file) {
3252 ret = -EBADF;
3253 goto out_drop_write;
3254 }
3255
3256 ret = -EXDEV;
3257 if (src_file.file->f_path.mnt != file->f_path.mnt)
3258 goto out_fput;
3259
3260 src = file_inode(src_file.file);
3261
3262 ret = -EINVAL;
3263 if (src == inode)
3264 same_inode = 1;
3265
3266 /* the src must be open for reading */
3267 if (!(src_file.file->f_mode & FMODE_READ))
3268 goto out_fput;
3269
3270 /* don't make the dst file partly checksummed */
3271 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3272 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3273 goto out_fput;
3274
3275 ret = -EISDIR;
3276 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3277 goto out_fput;
3278
3279 ret = -EXDEV;
3280 if (src->i_sb != inode->i_sb)
3281 goto out_fput;
3282
3283 if (!same_inode) {
3284 if (inode < src) {
3285 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
3286 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
3287 } else {
3288 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
3289 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
3290 }
3291 } else {
3292 mutex_lock(&src->i_mutex);
3293 }
3294
3295 /* determine range to clone */
3296 ret = -EINVAL;
3297 if (off + len > src->i_size || off + len < off)
3298 goto out_unlock;
3299 if (len == 0)
3300 olen = len = src->i_size - off;
3301 /* if we extend to eof, continue to block boundary */
3302 if (off + len == src->i_size)
3303 len = ALIGN(src->i_size, bs) - off;
3304
3305 /* verify the end result is block aligned */
3306 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
3307 !IS_ALIGNED(destoff, bs))
3308 goto out_unlock;
3309
3310 /* verify if ranges are overlapped within the same file */
3311 if (same_inode) {
3312 if (destoff + len > off && destoff < off + len)
3313 goto out_unlock;
3314 }
3315
3316 if (destoff > inode->i_size) {
3317 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3318 if (ret)
3319 goto out_unlock;
3320 }
3321
3322 /* truncate page cache pages from target inode range */
3323 truncate_inode_pages_range(&inode->i_data, destoff,
3324 PAGE_CACHE_ALIGN(destoff + len) - 1);
3325
3326 lock_extent_range(src, off, len);
3327
3328 ret = btrfs_clone(src, inode, off, olen, len, destoff);
3329
3330 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
3331out_unlock:
3332 if (!same_inode) {
3333 if (inode < src) {
3334 mutex_unlock(&src->i_mutex);
3335 mutex_unlock(&inode->i_mutex);
3336 } else {
3337 mutex_unlock(&inode->i_mutex);
3338 mutex_unlock(&src->i_mutex);
3339 }
3340 } else {
3341 mutex_unlock(&src->i_mutex);
3342 }
3343out_fput:
3344 fdput(src_file);
3345out_drop_write:
3346 mnt_drop_write_file(file);
3347 return ret;
3348}
3349
3350static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3351{
3352 struct btrfs_ioctl_clone_range_args args;
3353
3354 if (copy_from_user(&args, argp, sizeof(args)))
3355 return -EFAULT;
3356 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
3357 args.src_length, args.dest_offset);
3358}
3359
3360/*
3361 * there are many ways the trans_start and trans_end ioctls can lead
3362 * to deadlocks. They should only be used by applications that
3363 * basically own the machine, and have a very in depth understanding
3364 * of all the possible deadlocks and enospc problems.
3365 */
3366static long btrfs_ioctl_trans_start(struct file *file)
3367{
3368 struct inode *inode = file_inode(file);
3369 struct btrfs_root *root = BTRFS_I(inode)->root;
3370 struct btrfs_trans_handle *trans;
3371 int ret;
3372
3373 ret = -EPERM;
3374 if (!capable(CAP_SYS_ADMIN))
3375 goto out;
3376
3377 ret = -EINPROGRESS;
3378 if (file->private_data)
3379 goto out;
3380
3381 ret = -EROFS;
3382 if (btrfs_root_readonly(root))
3383 goto out;
3384
3385 ret = mnt_want_write_file(file);
3386 if (ret)
3387 goto out;
3388
3389 atomic_inc(&root->fs_info->open_ioctl_trans);
3390
3391 ret = -ENOMEM;
3392 trans = btrfs_start_ioctl_transaction(root);
3393 if (IS_ERR(trans))
3394 goto out_drop;
3395
3396 file->private_data = trans;
3397 return 0;
3398
3399out_drop:
3400 atomic_dec(&root->fs_info->open_ioctl_trans);
3401 mnt_drop_write_file(file);
3402out:
3403 return ret;
3404}
3405
3406static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3407{
3408 struct inode *inode = file_inode(file);
3409 struct btrfs_root *root = BTRFS_I(inode)->root;
3410 struct btrfs_root *new_root;
3411 struct btrfs_dir_item *di;
3412 struct btrfs_trans_handle *trans;
3413 struct btrfs_path *path;
3414 struct btrfs_key location;
3415 struct btrfs_disk_key disk_key;
3416 u64 objectid = 0;
3417 u64 dir_id;
3418 int ret;
3419
3420 if (!capable(CAP_SYS_ADMIN))
3421 return -EPERM;
3422
3423 ret = mnt_want_write_file(file);
3424 if (ret)
3425 return ret;
3426
3427 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3428 ret = -EFAULT;
3429 goto out;
3430 }
3431
3432 if (!objectid)
3433 objectid = BTRFS_FS_TREE_OBJECTID;
3434
3435 location.objectid = objectid;
3436 location.type = BTRFS_ROOT_ITEM_KEY;
3437 location.offset = (u64)-1;
3438
3439 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
3440 if (IS_ERR(new_root)) {
3441 ret = PTR_ERR(new_root);
3442 goto out;
3443 }
3444
3445 path = btrfs_alloc_path();
3446 if (!path) {
3447 ret = -ENOMEM;
3448 goto out;
3449 }
3450 path->leave_spinning = 1;
3451
3452 trans = btrfs_start_transaction(root, 1);
3453 if (IS_ERR(trans)) {
3454 btrfs_free_path(path);
3455 ret = PTR_ERR(trans);
3456 goto out;
3457 }
3458
3459 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3460 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
3461 dir_id, "default", 7, 1);
3462 if (IS_ERR_OR_NULL(di)) {
3463 btrfs_free_path(path);
3464 btrfs_end_transaction(trans, root);
3465 btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
3466 "item, this isn't going to work");
3467 ret = -ENOENT;
3468 goto out;
3469 }
3470
3471 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3472 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3473 btrfs_mark_buffer_dirty(path->nodes[0]);
3474 btrfs_free_path(path);
3475
3476 btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
3477 btrfs_end_transaction(trans, root);
3478out:
3479 mnt_drop_write_file(file);
3480 return ret;
3481}
3482
3483void btrfs_get_block_group_info(struct list_head *groups_list,
3484 struct btrfs_ioctl_space_info *space)
3485{
3486 struct btrfs_block_group_cache *block_group;
3487
3488 space->total_bytes = 0;
3489 space->used_bytes = 0;
3490 space->flags = 0;
3491 list_for_each_entry(block_group, groups_list, list) {
3492 space->flags = block_group->flags;
3493 space->total_bytes += block_group->key.offset;
3494 space->used_bytes +=
3495 btrfs_block_group_used(&block_group->item);
3496 }
3497}
3498
3499static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
3500{
3501 struct btrfs_ioctl_space_args space_args;
3502 struct btrfs_ioctl_space_info space;
3503 struct btrfs_ioctl_space_info *dest;
3504 struct btrfs_ioctl_space_info *dest_orig;
3505 struct btrfs_ioctl_space_info __user *user_dest;
3506 struct btrfs_space_info *info;
3507 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3508 BTRFS_BLOCK_GROUP_SYSTEM,
3509 BTRFS_BLOCK_GROUP_METADATA,
3510 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3511 int num_types = 4;
3512 int alloc_size;
3513 int ret = 0;
3514 u64 slot_count = 0;
3515 int i, c;
3516
3517 if (copy_from_user(&space_args,
3518 (struct btrfs_ioctl_space_args __user *)arg,
3519 sizeof(space_args)))
3520 return -EFAULT;
3521
3522 for (i = 0; i < num_types; i++) {
3523 struct btrfs_space_info *tmp;
3524
3525 info = NULL;
3526 rcu_read_lock();
3527 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3528 list) {
3529 if (tmp->flags == types[i]) {
3530 info = tmp;
3531 break;
3532 }
3533 }
3534 rcu_read_unlock();
3535
3536 if (!info)
3537 continue;
3538
3539 down_read(&info->groups_sem);
3540 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3541 if (!list_empty(&info->block_groups[c]))
3542 slot_count++;
3543 }
3544 up_read(&info->groups_sem);
3545 }
3546
3547 /*
3548 * Global block reserve, exported as a space_info
3549 */
3550 slot_count++;
3551
3552 /* space_slots == 0 means they are asking for a count */
3553 if (space_args.space_slots == 0) {
3554 space_args.total_spaces = slot_count;
3555 goto out;
3556 }
3557
3558 slot_count = min_t(u64, space_args.space_slots, slot_count);
3559
3560 alloc_size = sizeof(*dest) * slot_count;
3561
3562 /* we generally have at most 6 or so space infos, one for each raid
3563 * level. So, a whole page should be more than enough for everyone
3564 */
3565 if (alloc_size > PAGE_CACHE_SIZE)
3566 return -ENOMEM;
3567
3568 space_args.total_spaces = 0;
3569 dest = kmalloc(alloc_size, GFP_NOFS);
3570 if (!dest)
3571 return -ENOMEM;
3572 dest_orig = dest;
3573
3574 /* now we have a buffer to copy into */
3575 for (i = 0; i < num_types; i++) {
3576 struct btrfs_space_info *tmp;
3577
3578 if (!slot_count)
3579 break;
3580
3581 info = NULL;
3582 rcu_read_lock();
3583 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3584 list) {
3585 if (tmp->flags == types[i]) {
3586 info = tmp;
3587 break;
3588 }
3589 }
3590 rcu_read_unlock();
3591
3592 if (!info)
3593 continue;
3594 down_read(&info->groups_sem);
3595 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3596 if (!list_empty(&info->block_groups[c])) {
3597 btrfs_get_block_group_info(
3598 &info->block_groups[c], &space);
3599 memcpy(dest, &space, sizeof(space));
3600 dest++;
3601 space_args.total_spaces++;
3602 slot_count--;
3603 }
3604 if (!slot_count)
3605 break;
3606 }
3607 up_read(&info->groups_sem);
3608 }
3609
3610 /*
3611 * Add global block reserve
3612 */
3613 if (slot_count) {
3614 struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv;
3615
3616 spin_lock(&block_rsv->lock);
3617 space.total_bytes = block_rsv->size;
3618 space.used_bytes = block_rsv->size - block_rsv->reserved;
3619 spin_unlock(&block_rsv->lock);
3620 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
3621 memcpy(dest, &space, sizeof(space));
3622 space_args.total_spaces++;
3623 }
3624
3625 user_dest = (struct btrfs_ioctl_space_info __user *)
3626 (arg + sizeof(struct btrfs_ioctl_space_args));
3627
3628 if (copy_to_user(user_dest, dest_orig, alloc_size))
3629 ret = -EFAULT;
3630
3631 kfree(dest_orig);
3632out:
3633 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
3634 ret = -EFAULT;
3635
3636 return ret;
3637}
3638
3639/*
3640 * there are many ways the trans_start and trans_end ioctls can lead
3641 * to deadlocks. They should only be used by applications that
3642 * basically own the machine, and have a very in depth understanding
3643 * of all the possible deadlocks and enospc problems.
3644 */
3645long btrfs_ioctl_trans_end(struct file *file)
3646{
3647 struct inode *inode = file_inode(file);
3648 struct btrfs_root *root = BTRFS_I(inode)->root;
3649 struct btrfs_trans_handle *trans;
3650
3651 trans = file->private_data;
3652 if (!trans)
3653 return -EINVAL;
3654 file->private_data = NULL;
3655
3656 btrfs_end_transaction(trans, root);
3657
3658 atomic_dec(&root->fs_info->open_ioctl_trans);
3659
3660 mnt_drop_write_file(file);
3661 return 0;
3662}
3663
3664static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
3665 void __user *argp)
3666{
3667 struct btrfs_trans_handle *trans;
3668 u64 transid;
3669 int ret;
3670
3671 trans = btrfs_attach_transaction_barrier(root);
3672 if (IS_ERR(trans)) {
3673 if (PTR_ERR(trans) != -ENOENT)
3674 return PTR_ERR(trans);
3675
3676 /* No running transaction, don't bother */
3677 transid = root->fs_info->last_trans_committed;
3678 goto out;
3679 }
3680 transid = trans->transid;
3681 ret = btrfs_commit_transaction_async(trans, root, 0);
3682 if (ret) {
3683 btrfs_end_transaction(trans, root);
3684 return ret;
3685 }
3686out:
3687 if (argp)
3688 if (copy_to_user(argp, &transid, sizeof(transid)))
3689 return -EFAULT;
3690 return 0;
3691}
3692
3693static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
3694 void __user *argp)
3695{
3696 u64 transid;
3697
3698 if (argp) {
3699 if (copy_from_user(&transid, argp, sizeof(transid)))
3700 return -EFAULT;
3701 } else {
3702 transid = 0; /* current trans */
3703 }
3704 return btrfs_wait_for_commit(root, transid);
3705}
3706
3707static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
3708{
3709 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3710 struct btrfs_ioctl_scrub_args *sa;
3711 int ret;
3712
3713 if (!capable(CAP_SYS_ADMIN))
3714 return -EPERM;
3715
3716 sa = memdup_user(arg, sizeof(*sa));
3717 if (IS_ERR(sa))
3718 return PTR_ERR(sa);
3719
3720 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
3721 ret = mnt_want_write_file(file);
3722 if (ret)
3723 goto out;
3724 }
3725
3726 ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
3727 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
3728 0);
3729
3730 if (copy_to_user(arg, sa, sizeof(*sa)))
3731 ret = -EFAULT;
3732
3733 if (!(sa->flags & BTRFS_SCRUB_READONLY))
3734 mnt_drop_write_file(file);
3735out:
3736 kfree(sa);
3737 return ret;
3738}
3739
3740static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
3741{
3742 if (!capable(CAP_SYS_ADMIN))
3743 return -EPERM;
3744
3745 return btrfs_scrub_cancel(root->fs_info);
3746}
3747
3748static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
3749 void __user *arg)
3750{
3751 struct btrfs_ioctl_scrub_args *sa;
3752 int ret;
3753
3754 if (!capable(CAP_SYS_ADMIN))
3755 return -EPERM;
3756
3757 sa = memdup_user(arg, sizeof(*sa));
3758 if (IS_ERR(sa))
3759 return PTR_ERR(sa);
3760
3761 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
3762
3763 if (copy_to_user(arg, sa, sizeof(*sa)))
3764 ret = -EFAULT;
3765
3766 kfree(sa);
3767 return ret;
3768}
3769
3770static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
3771 void __user *arg)
3772{
3773 struct btrfs_ioctl_get_dev_stats *sa;
3774 int ret;
3775
3776 sa = memdup_user(arg, sizeof(*sa));
3777 if (IS_ERR(sa))
3778 return PTR_ERR(sa);
3779
3780 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3781 kfree(sa);
3782 return -EPERM;
3783 }
3784
3785 ret = btrfs_get_dev_stats(root, sa);
3786
3787 if (copy_to_user(arg, sa, sizeof(*sa)))
3788 ret = -EFAULT;
3789
3790 kfree(sa);
3791 return ret;
3792}
3793
3794static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
3795{
3796 struct btrfs_ioctl_dev_replace_args *p;
3797 int ret;
3798
3799 if (!capable(CAP_SYS_ADMIN))
3800 return -EPERM;
3801
3802 p = memdup_user(arg, sizeof(*p));
3803 if (IS_ERR(p))
3804 return PTR_ERR(p);
3805
3806 switch (p->cmd) {
3807 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3808 if (root->fs_info->sb->s_flags & MS_RDONLY) {
3809 ret = -EROFS;
3810 goto out;
3811 }
3812 if (atomic_xchg(
3813 &root->fs_info->mutually_exclusive_operation_running,
3814 1)) {
3815 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3816 } else {
3817 ret = btrfs_dev_replace_start(root, p);
3818 atomic_set(
3819 &root->fs_info->mutually_exclusive_operation_running,
3820 0);
3821 }
3822 break;
3823 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
3824 btrfs_dev_replace_status(root->fs_info, p);
3825 ret = 0;
3826 break;
3827 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
3828 ret = btrfs_dev_replace_cancel(root->fs_info, p);
3829 break;
3830 default:
3831 ret = -EINVAL;
3832 break;
3833 }
3834
3835 if (copy_to_user(arg, p, sizeof(*p)))
3836 ret = -EFAULT;
3837out:
3838 kfree(p);
3839 return ret;
3840}
3841
3842static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3843{
3844 int ret = 0;
3845 int i;
3846 u64 rel_ptr;
3847 int size;
3848 struct btrfs_ioctl_ino_path_args *ipa = NULL;
3849 struct inode_fs_paths *ipath = NULL;
3850 struct btrfs_path *path;
3851
3852 if (!capable(CAP_DAC_READ_SEARCH))
3853 return -EPERM;
3854
3855 path = btrfs_alloc_path();
3856 if (!path) {
3857 ret = -ENOMEM;
3858 goto out;
3859 }
3860
3861 ipa = memdup_user(arg, sizeof(*ipa));
3862 if (IS_ERR(ipa)) {
3863 ret = PTR_ERR(ipa);
3864 ipa = NULL;
3865 goto out;
3866 }
3867
3868 size = min_t(u32, ipa->size, 4096);
3869 ipath = init_ipath(size, root, path);
3870 if (IS_ERR(ipath)) {
3871 ret = PTR_ERR(ipath);
3872 ipath = NULL;
3873 goto out;
3874 }
3875
3876 ret = paths_from_inode(ipa->inum, ipath);
3877 if (ret < 0)
3878 goto out;
3879
3880 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3881 rel_ptr = ipath->fspath->val[i] -
3882 (u64)(unsigned long)ipath->fspath->val;
3883 ipath->fspath->val[i] = rel_ptr;
3884 }
3885
3886 ret = copy_to_user((void *)(unsigned long)ipa->fspath,
3887 (void *)(unsigned long)ipath->fspath, size);
3888 if (ret) {
3889 ret = -EFAULT;
3890 goto out;
3891 }
3892
3893out:
3894 btrfs_free_path(path);
3895 free_ipath(ipath);
3896 kfree(ipa);
3897
3898 return ret;
3899}
3900
3901static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3902{
3903 struct btrfs_data_container *inodes = ctx;
3904 const size_t c = 3 * sizeof(u64);
3905
3906 if (inodes->bytes_left >= c) {
3907 inodes->bytes_left -= c;
3908 inodes->val[inodes->elem_cnt] = inum;
3909 inodes->val[inodes->elem_cnt + 1] = offset;
3910 inodes->val[inodes->elem_cnt + 2] = root;
3911 inodes->elem_cnt += 3;
3912 } else {
3913 inodes->bytes_missing += c - inodes->bytes_left;
3914 inodes->bytes_left = 0;
3915 inodes->elem_missed += 3;
3916 }
3917
3918 return 0;
3919}
3920
3921static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
3922 void __user *arg)
3923{
3924 int ret = 0;
3925 int size;
3926 struct btrfs_ioctl_logical_ino_args *loi;
3927 struct btrfs_data_container *inodes = NULL;
3928 struct btrfs_path *path = NULL;
3929
3930 if (!capable(CAP_SYS_ADMIN))
3931 return -EPERM;
3932
3933 loi = memdup_user(arg, sizeof(*loi));
3934 if (IS_ERR(loi)) {
3935 ret = PTR_ERR(loi);
3936 loi = NULL;
3937 goto out;
3938 }
3939
3940 path = btrfs_alloc_path();
3941 if (!path) {
3942 ret = -ENOMEM;
3943 goto out;
3944 }
3945
3946 size = min_t(u32, loi->size, 64 * 1024);
3947 inodes = init_data_container(size);
3948 if (IS_ERR(inodes)) {
3949 ret = PTR_ERR(inodes);
3950 inodes = NULL;
3951 goto out;
3952 }
3953
3954 ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
3955 build_ino_list, inodes);
3956 if (ret == -EINVAL)
3957 ret = -ENOENT;
3958 if (ret < 0)
3959 goto out;
3960
3961 ret = copy_to_user((void *)(unsigned long)loi->inodes,
3962 (void *)(unsigned long)inodes, size);
3963 if (ret)
3964 ret = -EFAULT;
3965
3966out:
3967 btrfs_free_path(path);
3968 vfree(inodes);
3969 kfree(loi);
3970
3971 return ret;
3972}
3973
3974void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
3975 struct btrfs_ioctl_balance_args *bargs)
3976{
3977 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3978
3979 bargs->flags = bctl->flags;
3980
3981 if (atomic_read(&fs_info->balance_running))
3982 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3983 if (atomic_read(&fs_info->balance_pause_req))
3984 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3985 if (atomic_read(&fs_info->balance_cancel_req))
3986 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3987
3988 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3989 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3990 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3991
3992 if (lock) {
3993 spin_lock(&fs_info->balance_lock);
3994 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3995 spin_unlock(&fs_info->balance_lock);
3996 } else {
3997 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3998 }
3999}
4000
4001static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4002{
4003 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4004 struct btrfs_fs_info *fs_info = root->fs_info;
4005 struct btrfs_ioctl_balance_args *bargs;
4006 struct btrfs_balance_control *bctl;
4007 bool need_unlock; /* for mut. excl. ops lock */
4008 int ret;
4009
4010 if (!capable(CAP_SYS_ADMIN))
4011 return -EPERM;
4012
4013 ret = mnt_want_write_file(file);
4014 if (ret)
4015 return ret;
4016
4017again:
4018 if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
4019 mutex_lock(&fs_info->volume_mutex);
4020 mutex_lock(&fs_info->balance_mutex);
4021 need_unlock = true;
4022 goto locked;
4023 }
4024
4025 /*
4026 * mut. excl. ops lock is locked. Three possibilites:
4027 * (1) some other op is running
4028 * (2) balance is running
4029 * (3) balance is paused -- special case (think resume)
4030 */
4031 mutex_lock(&fs_info->balance_mutex);
4032 if (fs_info->balance_ctl) {
4033 /* this is either (2) or (3) */
4034 if (!atomic_read(&fs_info->balance_running)) {
4035 mutex_unlock(&fs_info->balance_mutex);
4036 if (!mutex_trylock(&fs_info->volume_mutex))
4037 goto again;
4038 mutex_lock(&fs_info->balance_mutex);
4039
4040 if (fs_info->balance_ctl &&
4041 !atomic_read(&fs_info->balance_running)) {
4042 /* this is (3) */
4043 need_unlock = false;
4044 goto locked;
4045 }
4046
4047 mutex_unlock(&fs_info->balance_mutex);
4048 mutex_unlock(&fs_info->volume_mutex);
4049 goto again;
4050 } else {
4051 /* this is (2) */
4052 mutex_unlock(&fs_info->balance_mutex);
4053 ret = -EINPROGRESS;
4054 goto out;
4055 }
4056 } else {
4057 /* this is (1) */
4058 mutex_unlock(&fs_info->balance_mutex);
4059 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4060 goto out;
4061 }
4062
4063locked:
4064 BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4065
4066 if (arg) {
4067 bargs = memdup_user(arg, sizeof(*bargs));
4068 if (IS_ERR(bargs)) {
4069 ret = PTR_ERR(bargs);
4070 goto out_unlock;
4071 }
4072
4073 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4074 if (!fs_info->balance_ctl) {
4075 ret = -ENOTCONN;
4076 goto out_bargs;
4077 }
4078
4079 bctl = fs_info->balance_ctl;
4080 spin_lock(&fs_info->balance_lock);
4081 bctl->flags |= BTRFS_BALANCE_RESUME;
4082 spin_unlock(&fs_info->balance_lock);
4083
4084 goto do_balance;
4085 }
4086 } else {
4087 bargs = NULL;
4088 }
4089
4090 if (fs_info->balance_ctl) {
4091 ret = -EINPROGRESS;
4092 goto out_bargs;
4093 }
4094
4095 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
4096 if (!bctl) {
4097 ret = -ENOMEM;
4098 goto out_bargs;
4099 }
4100
4101 bctl->fs_info = fs_info;
4102 if (arg) {
4103 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4104 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4105 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4106
4107 bctl->flags = bargs->flags;
4108 } else {
4109 /* balance everything - no filters */
4110 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4111 }
4112
4113do_balance:
4114 /*
4115 * Ownership of bctl and mutually_exclusive_operation_running
4116 * goes to to btrfs_balance. bctl is freed in __cancel_balance,
4117 * or, if restriper was paused all the way until unmount, in
4118 * free_fs_info. mutually_exclusive_operation_running is
4119 * cleared in __cancel_balance.
4120 */
4121 need_unlock = false;
4122
4123 ret = btrfs_balance(bctl, bargs);
4124
4125 if (arg) {
4126 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4127 ret = -EFAULT;
4128 }
4129
4130out_bargs:
4131 kfree(bargs);
4132out_unlock:
4133 mutex_unlock(&fs_info->balance_mutex);
4134 mutex_unlock(&fs_info->volume_mutex);
4135 if (need_unlock)
4136 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
4137out:
4138 mnt_drop_write_file(file);
4139 return ret;
4140}
4141
4142static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
4143{
4144 if (!capable(CAP_SYS_ADMIN))
4145 return -EPERM;
4146
4147 switch (cmd) {
4148 case BTRFS_BALANCE_CTL_PAUSE:
4149 return btrfs_pause_balance(root->fs_info);
4150 case BTRFS_BALANCE_CTL_CANCEL:
4151 return btrfs_cancel_balance(root->fs_info);
4152 }
4153
4154 return -EINVAL;
4155}
4156
4157static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
4158 void __user *arg)
4159{
4160 struct btrfs_fs_info *fs_info = root->fs_info;
4161 struct btrfs_ioctl_balance_args *bargs;
4162 int ret = 0;
4163
4164 if (!capable(CAP_SYS_ADMIN))
4165 return -EPERM;
4166
4167 mutex_lock(&fs_info->balance_mutex);
4168 if (!fs_info->balance_ctl) {
4169 ret = -ENOTCONN;
4170 goto out;
4171 }
4172
4173 bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
4174 if (!bargs) {
4175 ret = -ENOMEM;
4176 goto out;
4177 }
4178
4179 update_ioctl_balance_args(fs_info, 1, bargs);
4180
4181 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4182 ret = -EFAULT;
4183
4184 kfree(bargs);
4185out:
4186 mutex_unlock(&fs_info->balance_mutex);
4187 return ret;
4188}
4189
4190static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4191{
4192 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4193 struct btrfs_ioctl_quota_ctl_args *sa;
4194 struct btrfs_trans_handle *trans = NULL;
4195 int ret;
4196 int err;
4197
4198 if (!capable(CAP_SYS_ADMIN))
4199 return -EPERM;
4200
4201 ret = mnt_want_write_file(file);
4202 if (ret)
4203 return ret;
4204
4205 sa = memdup_user(arg, sizeof(*sa));
4206 if (IS_ERR(sa)) {
4207 ret = PTR_ERR(sa);
4208 goto drop_write;
4209 }
4210
4211 down_write(&root->fs_info->subvol_sem);
4212 trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
4213 if (IS_ERR(trans)) {
4214 ret = PTR_ERR(trans);
4215 goto out;
4216 }
4217
4218 switch (sa->cmd) {
4219 case BTRFS_QUOTA_CTL_ENABLE:
4220 ret = btrfs_quota_enable(trans, root->fs_info);
4221 break;
4222 case BTRFS_QUOTA_CTL_DISABLE:
4223 ret = btrfs_quota_disable(trans, root->fs_info);
4224 break;
4225 default:
4226 ret = -EINVAL;
4227 break;
4228 }
4229
4230 err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
4231 if (err && !ret)
4232 ret = err;
4233out:
4234 kfree(sa);
4235 up_write(&root->fs_info->subvol_sem);
4236drop_write:
4237 mnt_drop_write_file(file);
4238 return ret;
4239}
4240
4241static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4242{
4243 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4244 struct btrfs_ioctl_qgroup_assign_args *sa;
4245 struct btrfs_trans_handle *trans;
4246 int ret;
4247 int err;
4248
4249 if (!capable(CAP_SYS_ADMIN))
4250 return -EPERM;
4251
4252 ret = mnt_want_write_file(file);
4253 if (ret)
4254 return ret;
4255
4256 sa = memdup_user(arg, sizeof(*sa));
4257 if (IS_ERR(sa)) {
4258 ret = PTR_ERR(sa);
4259 goto drop_write;
4260 }
4261
4262 trans = btrfs_join_transaction(root);
4263 if (IS_ERR(trans)) {
4264 ret = PTR_ERR(trans);
4265 goto out;
4266 }
4267
4268 /* FIXME: check if the IDs really exist */
4269 if (sa->assign) {
4270 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
4271 sa->src, sa->dst);
4272 } else {
4273 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
4274 sa->src, sa->dst);
4275 }
4276
4277 err = btrfs_end_transaction(trans, root);
4278 if (err && !ret)
4279 ret = err;
4280
4281out:
4282 kfree(sa);
4283drop_write:
4284 mnt_drop_write_file(file);
4285 return ret;
4286}
4287
4288static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4289{
4290 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4291 struct btrfs_ioctl_qgroup_create_args *sa;
4292 struct btrfs_trans_handle *trans;
4293 int ret;
4294 int err;
4295
4296 if (!capable(CAP_SYS_ADMIN))
4297 return -EPERM;
4298
4299 ret = mnt_want_write_file(file);
4300 if (ret)
4301 return ret;
4302
4303 sa = memdup_user(arg, sizeof(*sa));
4304 if (IS_ERR(sa)) {
4305 ret = PTR_ERR(sa);
4306 goto drop_write;
4307 }
4308
4309 if (!sa->qgroupid) {
4310 ret = -EINVAL;
4311 goto out;
4312 }
4313
4314 trans = btrfs_join_transaction(root);
4315 if (IS_ERR(trans)) {
4316 ret = PTR_ERR(trans);
4317 goto out;
4318 }
4319
4320 /* FIXME: check if the IDs really exist */
4321 if (sa->create) {
4322 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
4323 NULL);
4324 } else {
4325 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
4326 }
4327
4328 err = btrfs_end_transaction(trans, root);
4329 if (err && !ret)
4330 ret = err;
4331
4332out:
4333 kfree(sa);
4334drop_write:
4335 mnt_drop_write_file(file);
4336 return ret;
4337}
4338
4339static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4340{
4341 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4342 struct btrfs_ioctl_qgroup_limit_args *sa;
4343 struct btrfs_trans_handle *trans;
4344 int ret;
4345 int err;
4346 u64 qgroupid;
4347
4348 if (!capable(CAP_SYS_ADMIN))
4349 return -EPERM;
4350
4351 ret = mnt_want_write_file(file);
4352 if (ret)
4353 return ret;
4354
4355 sa = memdup_user(arg, sizeof(*sa));
4356 if (IS_ERR(sa)) {
4357 ret = PTR_ERR(sa);
4358 goto drop_write;
4359 }
4360
4361 trans = btrfs_join_transaction(root);
4362 if (IS_ERR(trans)) {
4363 ret = PTR_ERR(trans);
4364 goto out;
4365 }
4366
4367 qgroupid = sa->qgroupid;
4368 if (!qgroupid) {
4369 /* take the current subvol as qgroup */
4370 qgroupid = root->root_key.objectid;
4371 }
4372
4373 /* FIXME: check if the IDs really exist */
4374 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
4375
4376 err = btrfs_end_transaction(trans, root);
4377 if (err && !ret)
4378 ret = err;
4379
4380out:
4381 kfree(sa);
4382drop_write:
4383 mnt_drop_write_file(file);
4384 return ret;
4385}
4386
4387static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4388{
4389 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4390 struct btrfs_ioctl_quota_rescan_args *qsa;
4391 int ret;
4392
4393 if (!capable(CAP_SYS_ADMIN))
4394 return -EPERM;
4395
4396 ret = mnt_want_write_file(file);
4397 if (ret)
4398 return ret;
4399
4400 qsa = memdup_user(arg, sizeof(*qsa));
4401 if (IS_ERR(qsa)) {
4402 ret = PTR_ERR(qsa);
4403 goto drop_write;
4404 }
4405
4406 if (qsa->flags) {
4407 ret = -EINVAL;
4408 goto out;
4409 }
4410
4411 ret = btrfs_qgroup_rescan(root->fs_info);
4412
4413out:
4414 kfree(qsa);
4415drop_write:
4416 mnt_drop_write_file(file);
4417 return ret;
4418}
4419
4420static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
4421{
4422 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4423 struct btrfs_ioctl_quota_rescan_args *qsa;
4424 int ret = 0;
4425
4426 if (!capable(CAP_SYS_ADMIN))
4427 return -EPERM;
4428
4429 qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
4430 if (!qsa)
4431 return -ENOMEM;
4432
4433 if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4434 qsa->flags = 1;
4435 qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
4436 }
4437
4438 if (copy_to_user(arg, qsa, sizeof(*qsa)))
4439 ret = -EFAULT;
4440
4441 kfree(qsa);
4442 return ret;
4443}
4444
4445static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
4446{
4447 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4448
4449 if (!capable(CAP_SYS_ADMIN))
4450 return -EPERM;
4451
4452 return btrfs_qgroup_wait_for_completion(root->fs_info);
4453}
4454
4455static long _btrfs_ioctl_set_received_subvol(struct file *file,
4456 struct btrfs_ioctl_received_subvol_args *sa)
4457{
4458 struct inode *inode = file_inode(file);
4459 struct btrfs_root *root = BTRFS_I(inode)->root;
4460 struct btrfs_root_item *root_item = &root->root_item;
4461 struct btrfs_trans_handle *trans;
4462 struct timespec ct = CURRENT_TIME;
4463 int ret = 0;
4464 int received_uuid_changed;
4465
4466 if (!inode_owner_or_capable(inode))
4467 return -EPERM;
4468
4469 ret = mnt_want_write_file(file);
4470 if (ret < 0)
4471 return ret;
4472
4473 down_write(&root->fs_info->subvol_sem);
4474
4475 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
4476 ret = -EINVAL;
4477 goto out;
4478 }
4479
4480 if (btrfs_root_readonly(root)) {
4481 ret = -EROFS;
4482 goto out;
4483 }
4484
4485 /*
4486 * 1 - root item
4487 * 2 - uuid items (received uuid + subvol uuid)
4488 */
4489 trans = btrfs_start_transaction(root, 3);
4490 if (IS_ERR(trans)) {
4491 ret = PTR_ERR(trans);
4492 trans = NULL;
4493 goto out;
4494 }
4495
4496 sa->rtransid = trans->transid;
4497 sa->rtime.sec = ct.tv_sec;
4498 sa->rtime.nsec = ct.tv_nsec;
4499
4500 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4501 BTRFS_UUID_SIZE);
4502 if (received_uuid_changed &&
4503 !btrfs_is_empty_uuid(root_item->received_uuid))
4504 btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
4505 root_item->received_uuid,
4506 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4507 root->root_key.objectid);
4508 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4509 btrfs_set_root_stransid(root_item, sa->stransid);
4510 btrfs_set_root_rtransid(root_item, sa->rtransid);
4511 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4512 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4513 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4514 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4515
4516 ret = btrfs_update_root(trans, root->fs_info->tree_root,
4517 &root->root_key, &root->root_item);
4518 if (ret < 0) {
4519 btrfs_end_transaction(trans, root);
4520 goto out;
4521 }
4522 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4523 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
4524 sa->uuid,
4525 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4526 root->root_key.objectid);
4527 if (ret < 0 && ret != -EEXIST) {
4528 btrfs_abort_transaction(trans, root, ret);
4529 goto out;
4530 }
4531 }
4532 ret = btrfs_commit_transaction(trans, root);
4533 if (ret < 0) {
4534 btrfs_abort_transaction(trans, root, ret);
4535 goto out;
4536 }
4537
4538out:
4539 up_write(&root->fs_info->subvol_sem);
4540 mnt_drop_write_file(file);
4541 return ret;
4542}
4543
4544#ifdef CONFIG_64BIT
4545static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4546 void __user *arg)
4547{
4548 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4549 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4550 int ret = 0;
4551
4552 args32 = memdup_user(arg, sizeof(*args32));
4553 if (IS_ERR(args32)) {
4554 ret = PTR_ERR(args32);
4555 args32 = NULL;
4556 goto out;
4557 }
4558
4559 args64 = kmalloc(sizeof(*args64), GFP_NOFS);
4560 if (!args64) {
4561 ret = -ENOMEM;
4562 goto out;
4563 }
4564
4565 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4566 args64->stransid = args32->stransid;
4567 args64->rtransid = args32->rtransid;
4568 args64->stime.sec = args32->stime.sec;
4569 args64->stime.nsec = args32->stime.nsec;
4570 args64->rtime.sec = args32->rtime.sec;
4571 args64->rtime.nsec = args32->rtime.nsec;
4572 args64->flags = args32->flags;
4573
4574 ret = _btrfs_ioctl_set_received_subvol(file, args64);
4575 if (ret)
4576 goto out;
4577
4578 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4579 args32->stransid = args64->stransid;
4580 args32->rtransid = args64->rtransid;
4581 args32->stime.sec = args64->stime.sec;
4582 args32->stime.nsec = args64->stime.nsec;
4583 args32->rtime.sec = args64->rtime.sec;
4584 args32->rtime.nsec = args64->rtime.nsec;
4585 args32->flags = args64->flags;
4586
4587 ret = copy_to_user(arg, args32, sizeof(*args32));
4588 if (ret)
4589 ret = -EFAULT;
4590
4591out:
4592 kfree(args32);
4593 kfree(args64);
4594 return ret;
4595}
4596#endif
4597
4598static long btrfs_ioctl_set_received_subvol(struct file *file,
4599 void __user *arg)
4600{
4601 struct btrfs_ioctl_received_subvol_args *sa = NULL;
4602 int ret = 0;
4603
4604 sa = memdup_user(arg, sizeof(*sa));
4605 if (IS_ERR(sa)) {
4606 ret = PTR_ERR(sa);
4607 sa = NULL;
4608 goto out;
4609 }
4610
4611 ret = _btrfs_ioctl_set_received_subvol(file, sa);
4612
4613 if (ret)
4614 goto out;
4615
4616 ret = copy_to_user(arg, sa, sizeof(*sa));
4617 if (ret)
4618 ret = -EFAULT;
4619
4620out:
4621 kfree(sa);
4622 return ret;
4623}
4624
4625static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
4626{
4627 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4628 size_t len;
4629 int ret;
4630 char label[BTRFS_LABEL_SIZE];
4631
4632 spin_lock(&root->fs_info->super_lock);
4633 memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
4634 spin_unlock(&root->fs_info->super_lock);
4635
4636 len = strnlen(label, BTRFS_LABEL_SIZE);
4637
4638 if (len == BTRFS_LABEL_SIZE) {
4639 btrfs_warn(root->fs_info,
4640 "label is too long, return the first %zu bytes", --len);
4641 }
4642
4643 ret = copy_to_user(arg, label, len);
4644
4645 return ret ? -EFAULT : 0;
4646}
4647
4648static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
4649{
4650 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4651 struct btrfs_super_block *super_block = root->fs_info->super_copy;
4652 struct btrfs_trans_handle *trans;
4653 char label[BTRFS_LABEL_SIZE];
4654 int ret;
4655
4656 if (!capable(CAP_SYS_ADMIN))
4657 return -EPERM;
4658
4659 if (copy_from_user(label, arg, sizeof(label)))
4660 return -EFAULT;
4661
4662 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
4663 btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
4664 BTRFS_LABEL_SIZE - 1);
4665 return -EINVAL;
4666 }
4667
4668 ret = mnt_want_write_file(file);
4669 if (ret)
4670 return ret;
4671
4672 trans = btrfs_start_transaction(root, 0);
4673 if (IS_ERR(trans)) {
4674 ret = PTR_ERR(trans);
4675 goto out_unlock;
4676 }
4677
4678 spin_lock(&root->fs_info->super_lock);
4679 strcpy(super_block->label, label);
4680 spin_unlock(&root->fs_info->super_lock);
4681 ret = btrfs_commit_transaction(trans, root);
4682
4683out_unlock:
4684 mnt_drop_write_file(file);
4685 return ret;
4686}
4687
4688#define INIT_FEATURE_FLAGS(suffix) \
4689 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
4690 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
4691 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
4692
4693static int btrfs_ioctl_get_supported_features(struct file *file,
4694 void __user *arg)
4695{
4696 static struct btrfs_ioctl_feature_flags features[3] = {
4697 INIT_FEATURE_FLAGS(SUPP),
4698 INIT_FEATURE_FLAGS(SAFE_SET),
4699 INIT_FEATURE_FLAGS(SAFE_CLEAR)
4700 };
4701
4702 if (copy_to_user(arg, &features, sizeof(features)))
4703 return -EFAULT;
4704
4705 return 0;
4706}
4707
4708static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
4709{
4710 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4711 struct btrfs_super_block *super_block = root->fs_info->super_copy;
4712 struct btrfs_ioctl_feature_flags features;
4713
4714 features.compat_flags = btrfs_super_compat_flags(super_block);
4715 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
4716 features.incompat_flags = btrfs_super_incompat_flags(super_block);
4717
4718 if (copy_to_user(arg, &features, sizeof(features)))
4719 return -EFAULT;
4720
4721 return 0;
4722}
4723
4724static int check_feature_bits(struct btrfs_root *root,
4725 enum btrfs_feature_set set,
4726 u64 change_mask, u64 flags, u64 supported_flags,
4727 u64 safe_set, u64 safe_clear)
4728{
4729 const char *type = btrfs_feature_set_names[set];
4730 char *names;
4731 u64 disallowed, unsupported;
4732 u64 set_mask = flags & change_mask;
4733 u64 clear_mask = ~flags & change_mask;
4734
4735 unsupported = set_mask & ~supported_flags;
4736 if (unsupported) {
4737 names = btrfs_printable_features(set, unsupported);
4738 if (names) {
4739 btrfs_warn(root->fs_info,
4740 "this kernel does not support the %s feature bit%s",
4741 names, strchr(names, ',') ? "s" : "");
4742 kfree(names);
4743 } else
4744 btrfs_warn(root->fs_info,
4745 "this kernel does not support %s bits 0x%llx",
4746 type, unsupported);
4747 return -EOPNOTSUPP;
4748 }
4749
4750 disallowed = set_mask & ~safe_set;
4751 if (disallowed) {
4752 names = btrfs_printable_features(set, disallowed);
4753 if (names) {
4754 btrfs_warn(root->fs_info,
4755 "can't set the %s feature bit%s while mounted",
4756 names, strchr(names, ',') ? "s" : "");
4757 kfree(names);
4758 } else
4759 btrfs_warn(root->fs_info,
4760 "can't set %s bits 0x%llx while mounted",
4761 type, disallowed);
4762 return -EPERM;
4763 }
4764
4765 disallowed = clear_mask & ~safe_clear;
4766 if (disallowed) {
4767 names = btrfs_printable_features(set, disallowed);
4768 if (names) {
4769 btrfs_warn(root->fs_info,
4770 "can't clear the %s feature bit%s while mounted",
4771 names, strchr(names, ',') ? "s" : "");
4772 kfree(names);
4773 } else
4774 btrfs_warn(root->fs_info,
4775 "can't clear %s bits 0x%llx while mounted",
4776 type, disallowed);
4777 return -EPERM;
4778 }
4779
4780 return 0;
4781}
4782
4783#define check_feature(root, change_mask, flags, mask_base) \
4784check_feature_bits(root, FEAT_##mask_base, change_mask, flags, \
4785 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
4786 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
4787 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
4788
4789static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
4790{
4791 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4792 struct btrfs_super_block *super_block = root->fs_info->super_copy;
4793 struct btrfs_ioctl_feature_flags flags[2];
4794 struct btrfs_trans_handle *trans;
4795 u64 newflags;
4796 int ret;
4797
4798 if (!capable(CAP_SYS_ADMIN))
4799 return -EPERM;
4800
4801 if (copy_from_user(flags, arg, sizeof(flags)))
4802 return -EFAULT;
4803
4804 /* Nothing to do */
4805 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
4806 !flags[0].incompat_flags)
4807 return 0;
4808
4809 ret = check_feature(root, flags[0].compat_flags,
4810 flags[1].compat_flags, COMPAT);
4811 if (ret)
4812 return ret;
4813
4814 ret = check_feature(root, flags[0].compat_ro_flags,
4815 flags[1].compat_ro_flags, COMPAT_RO);
4816 if (ret)
4817 return ret;
4818
4819 ret = check_feature(root, flags[0].incompat_flags,
4820 flags[1].incompat_flags, INCOMPAT);
4821 if (ret)
4822 return ret;
4823
4824 trans = btrfs_start_transaction(root, 0);
4825 if (IS_ERR(trans))
4826 return PTR_ERR(trans);
4827
4828 spin_lock(&root->fs_info->super_lock);
4829 newflags = btrfs_super_compat_flags(super_block);
4830 newflags |= flags[0].compat_flags & flags[1].compat_flags;
4831 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
4832 btrfs_set_super_compat_flags(super_block, newflags);
4833
4834 newflags = btrfs_super_compat_ro_flags(super_block);
4835 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
4836 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
4837 btrfs_set_super_compat_ro_flags(super_block, newflags);
4838
4839 newflags = btrfs_super_incompat_flags(super_block);
4840 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
4841 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
4842 btrfs_set_super_incompat_flags(super_block, newflags);
4843 spin_unlock(&root->fs_info->super_lock);
4844
4845 return btrfs_commit_transaction(trans, root);
4846}
4847
4848long btrfs_ioctl(struct file *file, unsigned int
4849 cmd, unsigned long arg)
4850{
4851 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4852 void __user *argp = (void __user *)arg;
4853
4854 switch (cmd) {
4855 case FS_IOC_GETFLAGS:
4856 return btrfs_ioctl_getflags(file, argp);
4857 case FS_IOC_SETFLAGS:
4858 return btrfs_ioctl_setflags(file, argp);
4859 case FS_IOC_GETVERSION:
4860 return btrfs_ioctl_getversion(file, argp);
4861 case FITRIM:
4862 return btrfs_ioctl_fitrim(file, argp);
4863 case BTRFS_IOC_SNAP_CREATE:
4864 return btrfs_ioctl_snap_create(file, argp, 0);
4865 case BTRFS_IOC_SNAP_CREATE_V2:
4866 return btrfs_ioctl_snap_create_v2(file, argp, 0);
4867 case BTRFS_IOC_SUBVOL_CREATE:
4868 return btrfs_ioctl_snap_create(file, argp, 1);
4869 case BTRFS_IOC_SUBVOL_CREATE_V2:
4870 return btrfs_ioctl_snap_create_v2(file, argp, 1);
4871 case BTRFS_IOC_SNAP_DESTROY:
4872 return btrfs_ioctl_snap_destroy(file, argp);
4873 case BTRFS_IOC_SUBVOL_GETFLAGS:
4874 return btrfs_ioctl_subvol_getflags(file, argp);
4875 case BTRFS_IOC_SUBVOL_SETFLAGS:
4876 return btrfs_ioctl_subvol_setflags(file, argp);
4877 case BTRFS_IOC_DEFAULT_SUBVOL:
4878 return btrfs_ioctl_default_subvol(file, argp);
4879 case BTRFS_IOC_DEFRAG:
4880 return btrfs_ioctl_defrag(file, NULL);
4881 case BTRFS_IOC_DEFRAG_RANGE:
4882 return btrfs_ioctl_defrag(file, argp);
4883 case BTRFS_IOC_RESIZE:
4884 return btrfs_ioctl_resize(file, argp);
4885 case BTRFS_IOC_ADD_DEV:
4886 return btrfs_ioctl_add_dev(root, argp);
4887 case BTRFS_IOC_RM_DEV:
4888 return btrfs_ioctl_rm_dev(file, argp);
4889 case BTRFS_IOC_FS_INFO:
4890 return btrfs_ioctl_fs_info(root, argp);
4891 case BTRFS_IOC_DEV_INFO:
4892 return btrfs_ioctl_dev_info(root, argp);
4893 case BTRFS_IOC_BALANCE:
4894 return btrfs_ioctl_balance(file, NULL);
4895 case BTRFS_IOC_CLONE:
4896 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
4897 case BTRFS_IOC_CLONE_RANGE:
4898 return btrfs_ioctl_clone_range(file, argp);
4899 case BTRFS_IOC_TRANS_START:
4900 return btrfs_ioctl_trans_start(file);
4901 case BTRFS_IOC_TRANS_END:
4902 return btrfs_ioctl_trans_end(file);
4903 case BTRFS_IOC_TREE_SEARCH:
4904 return btrfs_ioctl_tree_search(file, argp);
4905 case BTRFS_IOC_INO_LOOKUP:
4906 return btrfs_ioctl_ino_lookup(file, argp);
4907 case BTRFS_IOC_INO_PATHS:
4908 return btrfs_ioctl_ino_to_path(root, argp);
4909 case BTRFS_IOC_LOGICAL_INO:
4910 return btrfs_ioctl_logical_to_ino(root, argp);
4911 case BTRFS_IOC_SPACE_INFO:
4912 return btrfs_ioctl_space_info(root, argp);
4913 case BTRFS_IOC_SYNC: {
4914 int ret;
4915
4916 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
4917 if (ret)
4918 return ret;
4919 ret = btrfs_sync_fs(file->f_dentry->d_sb, 1);
4920 return ret;
4921 }
4922 case BTRFS_IOC_START_SYNC:
4923 return btrfs_ioctl_start_sync(root, argp);
4924 case BTRFS_IOC_WAIT_SYNC:
4925 return btrfs_ioctl_wait_sync(root, argp);
4926 case BTRFS_IOC_SCRUB:
4927 return btrfs_ioctl_scrub(file, argp);
4928 case BTRFS_IOC_SCRUB_CANCEL:
4929 return btrfs_ioctl_scrub_cancel(root, argp);
4930 case BTRFS_IOC_SCRUB_PROGRESS:
4931 return btrfs_ioctl_scrub_progress(root, argp);
4932 case BTRFS_IOC_BALANCE_V2:
4933 return btrfs_ioctl_balance(file, argp);
4934 case BTRFS_IOC_BALANCE_CTL:
4935 return btrfs_ioctl_balance_ctl(root, arg);
4936 case BTRFS_IOC_BALANCE_PROGRESS:
4937 return btrfs_ioctl_balance_progress(root, argp);
4938 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
4939 return btrfs_ioctl_set_received_subvol(file, argp);
4940#ifdef CONFIG_64BIT
4941 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
4942 return btrfs_ioctl_set_received_subvol_32(file, argp);
4943#endif
4944 case BTRFS_IOC_SEND:
4945 return btrfs_ioctl_send(file, argp);
4946 case BTRFS_IOC_GET_DEV_STATS:
4947 return btrfs_ioctl_get_dev_stats(root, argp);
4948 case BTRFS_IOC_QUOTA_CTL:
4949 return btrfs_ioctl_quota_ctl(file, argp);
4950 case BTRFS_IOC_QGROUP_ASSIGN:
4951 return btrfs_ioctl_qgroup_assign(file, argp);
4952 case BTRFS_IOC_QGROUP_CREATE:
4953 return btrfs_ioctl_qgroup_create(file, argp);
4954 case BTRFS_IOC_QGROUP_LIMIT:
4955 return btrfs_ioctl_qgroup_limit(file, argp);
4956 case BTRFS_IOC_QUOTA_RESCAN:
4957 return btrfs_ioctl_quota_rescan(file, argp);
4958 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
4959 return btrfs_ioctl_quota_rescan_status(file, argp);
4960 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
4961 return btrfs_ioctl_quota_rescan_wait(file, argp);
4962 case BTRFS_IOC_DEV_REPLACE:
4963 return btrfs_ioctl_dev_replace(root, argp);
4964 case BTRFS_IOC_GET_FSLABEL:
4965 return btrfs_ioctl_get_fslabel(file, argp);
4966 case BTRFS_IOC_SET_FSLABEL:
4967 return btrfs_ioctl_set_fslabel(file, argp);
4968 case BTRFS_IOC_FILE_EXTENT_SAME:
4969 return btrfs_ioctl_file_extent_same(file, argp);
4970 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
4971 return btrfs_ioctl_get_supported_features(file, argp);
4972 case BTRFS_IOC_GET_FEATURES:
4973 return btrfs_ioctl_get_features(file, argp);
4974 case BTRFS_IOC_SET_FEATURES:
4975 return btrfs_ioctl_set_features(file, argp);
4976 }
4977
4978 return -ENOTTY;
4979}