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btrfs: Fix suspicious RCU usage warning in btrfs_debug_in_rcu
[mirror_ubuntu-hirsute-kernel.git] / fs / btrfs / ioctl.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #include <linux/kernel.h>
7 #include <linux/bio.h>
8 #include <linux/file.h>
9 #include <linux/fs.h>
10 #include <linux/fsnotify.h>
11 #include <linux/pagemap.h>
12 #include <linux/highmem.h>
13 #include <linux/time.h>
14 #include <linux/string.h>
15 #include <linux/backing-dev.h>
16 #include <linux/mount.h>
17 #include <linux/namei.h>
18 #include <linux/writeback.h>
19 #include <linux/compat.h>
20 #include <linux/security.h>
21 #include <linux/xattr.h>
22 #include <linux/mm.h>
23 #include <linux/slab.h>
24 #include <linux/blkdev.h>
25 #include <linux/uuid.h>
26 #include <linux/btrfs.h>
27 #include <linux/uaccess.h>
28 #include <linux/iversion.h>
29 #include "ctree.h"
30 #include "disk-io.h"
31 #include "transaction.h"
32 #include "btrfs_inode.h"
33 #include "print-tree.h"
34 #include "volumes.h"
35 #include "locking.h"
36 #include "inode-map.h"
37 #include "backref.h"
38 #include "rcu-string.h"
39 #include "send.h"
40 #include "dev-replace.h"
41 #include "props.h"
42 #include "sysfs.h"
43 #include "qgroup.h"
44 #include "tree-log.h"
45 #include "compression.h"
46
47 #ifdef CONFIG_64BIT
48 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
49 * structures are incorrect, as the timespec structure from userspace
50 * is 4 bytes too small. We define these alternatives here to teach
51 * the kernel about the 32-bit struct packing.
52 */
53 struct btrfs_ioctl_timespec_32 {
54 __u64 sec;
55 __u32 nsec;
56 } __attribute__ ((__packed__));
57
58 struct btrfs_ioctl_received_subvol_args_32 {
59 char uuid[BTRFS_UUID_SIZE]; /* in */
60 __u64 stransid; /* in */
61 __u64 rtransid; /* out */
62 struct btrfs_ioctl_timespec_32 stime; /* in */
63 struct btrfs_ioctl_timespec_32 rtime; /* out */
64 __u64 flags; /* in */
65 __u64 reserved[16]; /* in */
66 } __attribute__ ((__packed__));
67
68 #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
69 struct btrfs_ioctl_received_subvol_args_32)
70 #endif
71
72 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
73 struct btrfs_ioctl_send_args_32 {
74 __s64 send_fd; /* in */
75 __u64 clone_sources_count; /* in */
76 compat_uptr_t clone_sources; /* in */
77 __u64 parent_root; /* in */
78 __u64 flags; /* in */
79 __u64 reserved[4]; /* in */
80 } __attribute__ ((__packed__));
81
82 #define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \
83 struct btrfs_ioctl_send_args_32)
84 #endif
85
86 static int btrfs_clone(struct inode *src, struct inode *inode,
87 u64 off, u64 olen, u64 olen_aligned, u64 destoff,
88 int no_time_update);
89
90 /* Mask out flags that are inappropriate for the given type of inode. */
91 static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,
92 unsigned int flags)
93 {
94 if (S_ISDIR(inode->i_mode))
95 return flags;
96 else if (S_ISREG(inode->i_mode))
97 return flags & ~FS_DIRSYNC_FL;
98 else
99 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
100 }
101
102 /*
103 * Export internal inode flags to the format expected by the FS_IOC_GETFLAGS
104 * ioctl.
105 */
106 static unsigned int btrfs_inode_flags_to_fsflags(unsigned int flags)
107 {
108 unsigned int iflags = 0;
109
110 if (flags & BTRFS_INODE_SYNC)
111 iflags |= FS_SYNC_FL;
112 if (flags & BTRFS_INODE_IMMUTABLE)
113 iflags |= FS_IMMUTABLE_FL;
114 if (flags & BTRFS_INODE_APPEND)
115 iflags |= FS_APPEND_FL;
116 if (flags & BTRFS_INODE_NODUMP)
117 iflags |= FS_NODUMP_FL;
118 if (flags & BTRFS_INODE_NOATIME)
119 iflags |= FS_NOATIME_FL;
120 if (flags & BTRFS_INODE_DIRSYNC)
121 iflags |= FS_DIRSYNC_FL;
122 if (flags & BTRFS_INODE_NODATACOW)
123 iflags |= FS_NOCOW_FL;
124
125 if (flags & BTRFS_INODE_NOCOMPRESS)
126 iflags |= FS_NOCOMP_FL;
127 else if (flags & BTRFS_INODE_COMPRESS)
128 iflags |= FS_COMPR_FL;
129
130 return iflags;
131 }
132
133 /*
134 * Update inode->i_flags based on the btrfs internal flags.
135 */
136 void btrfs_sync_inode_flags_to_i_flags(struct inode *inode)
137 {
138 struct btrfs_inode *binode = BTRFS_I(inode);
139 unsigned int new_fl = 0;
140
141 if (binode->flags & BTRFS_INODE_SYNC)
142 new_fl |= S_SYNC;
143 if (binode->flags & BTRFS_INODE_IMMUTABLE)
144 new_fl |= S_IMMUTABLE;
145 if (binode->flags & BTRFS_INODE_APPEND)
146 new_fl |= S_APPEND;
147 if (binode->flags & BTRFS_INODE_NOATIME)
148 new_fl |= S_NOATIME;
149 if (binode->flags & BTRFS_INODE_DIRSYNC)
150 new_fl |= S_DIRSYNC;
151
152 set_mask_bits(&inode->i_flags,
153 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
154 new_fl);
155 }
156
157 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
158 {
159 struct btrfs_inode *binode = BTRFS_I(file_inode(file));
160 unsigned int flags = btrfs_inode_flags_to_fsflags(binode->flags);
161
162 if (copy_to_user(arg, &flags, sizeof(flags)))
163 return -EFAULT;
164 return 0;
165 }
166
167 /* Check if @flags are a supported and valid set of FS_*_FL flags */
168 static int check_fsflags(unsigned int flags)
169 {
170 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
171 FS_NOATIME_FL | FS_NODUMP_FL | \
172 FS_SYNC_FL | FS_DIRSYNC_FL | \
173 FS_NOCOMP_FL | FS_COMPR_FL |
174 FS_NOCOW_FL))
175 return -EOPNOTSUPP;
176
177 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
178 return -EINVAL;
179
180 return 0;
181 }
182
183 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
184 {
185 struct inode *inode = file_inode(file);
186 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
187 struct btrfs_inode *binode = BTRFS_I(inode);
188 struct btrfs_root *root = binode->root;
189 struct btrfs_trans_handle *trans;
190 unsigned int fsflags, old_fsflags;
191 int ret;
192 u64 old_flags;
193 unsigned int old_i_flags;
194 umode_t mode;
195
196 if (!inode_owner_or_capable(inode))
197 return -EPERM;
198
199 if (btrfs_root_readonly(root))
200 return -EROFS;
201
202 if (copy_from_user(&fsflags, arg, sizeof(fsflags)))
203 return -EFAULT;
204
205 ret = check_fsflags(fsflags);
206 if (ret)
207 return ret;
208
209 ret = mnt_want_write_file(file);
210 if (ret)
211 return ret;
212
213 inode_lock(inode);
214
215 old_flags = binode->flags;
216 old_i_flags = inode->i_flags;
217 mode = inode->i_mode;
218
219 fsflags = btrfs_mask_fsflags_for_type(inode, fsflags);
220 old_fsflags = btrfs_inode_flags_to_fsflags(binode->flags);
221 if ((fsflags ^ old_fsflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
222 if (!capable(CAP_LINUX_IMMUTABLE)) {
223 ret = -EPERM;
224 goto out_unlock;
225 }
226 }
227
228 if (fsflags & FS_SYNC_FL)
229 binode->flags |= BTRFS_INODE_SYNC;
230 else
231 binode->flags &= ~BTRFS_INODE_SYNC;
232 if (fsflags & FS_IMMUTABLE_FL)
233 binode->flags |= BTRFS_INODE_IMMUTABLE;
234 else
235 binode->flags &= ~BTRFS_INODE_IMMUTABLE;
236 if (fsflags & FS_APPEND_FL)
237 binode->flags |= BTRFS_INODE_APPEND;
238 else
239 binode->flags &= ~BTRFS_INODE_APPEND;
240 if (fsflags & FS_NODUMP_FL)
241 binode->flags |= BTRFS_INODE_NODUMP;
242 else
243 binode->flags &= ~BTRFS_INODE_NODUMP;
244 if (fsflags & FS_NOATIME_FL)
245 binode->flags |= BTRFS_INODE_NOATIME;
246 else
247 binode->flags &= ~BTRFS_INODE_NOATIME;
248 if (fsflags & FS_DIRSYNC_FL)
249 binode->flags |= BTRFS_INODE_DIRSYNC;
250 else
251 binode->flags &= ~BTRFS_INODE_DIRSYNC;
252 if (fsflags & FS_NOCOW_FL) {
253 if (S_ISREG(mode)) {
254 /*
255 * It's safe to turn csums off here, no extents exist.
256 * Otherwise we want the flag to reflect the real COW
257 * status of the file and will not set it.
258 */
259 if (inode->i_size == 0)
260 binode->flags |= BTRFS_INODE_NODATACOW
261 | BTRFS_INODE_NODATASUM;
262 } else {
263 binode->flags |= BTRFS_INODE_NODATACOW;
264 }
265 } else {
266 /*
267 * Revert back under same assumptions as above
268 */
269 if (S_ISREG(mode)) {
270 if (inode->i_size == 0)
271 binode->flags &= ~(BTRFS_INODE_NODATACOW
272 | BTRFS_INODE_NODATASUM);
273 } else {
274 binode->flags &= ~BTRFS_INODE_NODATACOW;
275 }
276 }
277
278 /*
279 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
280 * flag may be changed automatically if compression code won't make
281 * things smaller.
282 */
283 if (fsflags & FS_NOCOMP_FL) {
284 binode->flags &= ~BTRFS_INODE_COMPRESS;
285 binode->flags |= BTRFS_INODE_NOCOMPRESS;
286
287 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
288 if (ret && ret != -ENODATA)
289 goto out_drop;
290 } else if (fsflags & FS_COMPR_FL) {
291 const char *comp;
292
293 binode->flags |= BTRFS_INODE_COMPRESS;
294 binode->flags &= ~BTRFS_INODE_NOCOMPRESS;
295
296 comp = btrfs_compress_type2str(fs_info->compress_type);
297 if (!comp || comp[0] == 0)
298 comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);
299
300 ret = btrfs_set_prop(inode, "btrfs.compression",
301 comp, strlen(comp), 0);
302 if (ret)
303 goto out_drop;
304
305 } else {
306 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
307 if (ret && ret != -ENODATA)
308 goto out_drop;
309 binode->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
310 }
311
312 trans = btrfs_start_transaction(root, 1);
313 if (IS_ERR(trans)) {
314 ret = PTR_ERR(trans);
315 goto out_drop;
316 }
317
318 btrfs_sync_inode_flags_to_i_flags(inode);
319 inode_inc_iversion(inode);
320 inode->i_ctime = current_time(inode);
321 ret = btrfs_update_inode(trans, root, inode);
322
323 btrfs_end_transaction(trans);
324 out_drop:
325 if (ret) {
326 binode->flags = old_flags;
327 inode->i_flags = old_i_flags;
328 }
329
330 out_unlock:
331 inode_unlock(inode);
332 mnt_drop_write_file(file);
333 return ret;
334 }
335
336 /*
337 * Translate btrfs internal inode flags to xflags as expected by the
338 * FS_IOC_FSGETXATT ioctl. Filter only the supported ones, unknown flags are
339 * silently dropped.
340 */
341 static unsigned int btrfs_inode_flags_to_xflags(unsigned int flags)
342 {
343 unsigned int xflags = 0;
344
345 if (flags & BTRFS_INODE_APPEND)
346 xflags |= FS_XFLAG_APPEND;
347 if (flags & BTRFS_INODE_IMMUTABLE)
348 xflags |= FS_XFLAG_IMMUTABLE;
349 if (flags & BTRFS_INODE_NOATIME)
350 xflags |= FS_XFLAG_NOATIME;
351 if (flags & BTRFS_INODE_NODUMP)
352 xflags |= FS_XFLAG_NODUMP;
353 if (flags & BTRFS_INODE_SYNC)
354 xflags |= FS_XFLAG_SYNC;
355
356 return xflags;
357 }
358
359 /* Check if @flags are a supported and valid set of FS_XFLAGS_* flags */
360 static int check_xflags(unsigned int flags)
361 {
362 if (flags & ~(FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE | FS_XFLAG_NOATIME |
363 FS_XFLAG_NODUMP | FS_XFLAG_SYNC))
364 return -EOPNOTSUPP;
365 return 0;
366 }
367
368 /*
369 * Set the xflags from the internal inode flags. The remaining items of fsxattr
370 * are zeroed.
371 */
372 static int btrfs_ioctl_fsgetxattr(struct file *file, void __user *arg)
373 {
374 struct btrfs_inode *binode = BTRFS_I(file_inode(file));
375 struct fsxattr fa;
376
377 memset(&fa, 0, sizeof(fa));
378 fa.fsx_xflags = btrfs_inode_flags_to_xflags(binode->flags);
379
380 if (copy_to_user(arg, &fa, sizeof(fa)))
381 return -EFAULT;
382
383 return 0;
384 }
385
386 static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg)
387 {
388 struct inode *inode = file_inode(file);
389 struct btrfs_inode *binode = BTRFS_I(inode);
390 struct btrfs_root *root = binode->root;
391 struct btrfs_trans_handle *trans;
392 struct fsxattr fa;
393 unsigned old_flags;
394 unsigned old_i_flags;
395 int ret = 0;
396
397 if (!inode_owner_or_capable(inode))
398 return -EPERM;
399
400 if (btrfs_root_readonly(root))
401 return -EROFS;
402
403 memset(&fa, 0, sizeof(fa));
404 if (copy_from_user(&fa, arg, sizeof(fa)))
405 return -EFAULT;
406
407 ret = check_xflags(fa.fsx_xflags);
408 if (ret)
409 return ret;
410
411 if (fa.fsx_extsize != 0 || fa.fsx_projid != 0 || fa.fsx_cowextsize != 0)
412 return -EOPNOTSUPP;
413
414 ret = mnt_want_write_file(file);
415 if (ret)
416 return ret;
417
418 inode_lock(inode);
419
420 old_flags = binode->flags;
421 old_i_flags = inode->i_flags;
422
423 /* We need the capabilities to change append-only or immutable inode */
424 if (((old_flags & (BTRFS_INODE_APPEND | BTRFS_INODE_IMMUTABLE)) ||
425 (fa.fsx_xflags & (FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE))) &&
426 !capable(CAP_LINUX_IMMUTABLE)) {
427 ret = -EPERM;
428 goto out_unlock;
429 }
430
431 if (fa.fsx_xflags & FS_XFLAG_SYNC)
432 binode->flags |= BTRFS_INODE_SYNC;
433 else
434 binode->flags &= ~BTRFS_INODE_SYNC;
435 if (fa.fsx_xflags & FS_XFLAG_IMMUTABLE)
436 binode->flags |= BTRFS_INODE_IMMUTABLE;
437 else
438 binode->flags &= ~BTRFS_INODE_IMMUTABLE;
439 if (fa.fsx_xflags & FS_XFLAG_APPEND)
440 binode->flags |= BTRFS_INODE_APPEND;
441 else
442 binode->flags &= ~BTRFS_INODE_APPEND;
443 if (fa.fsx_xflags & FS_XFLAG_NODUMP)
444 binode->flags |= BTRFS_INODE_NODUMP;
445 else
446 binode->flags &= ~BTRFS_INODE_NODUMP;
447 if (fa.fsx_xflags & FS_XFLAG_NOATIME)
448 binode->flags |= BTRFS_INODE_NOATIME;
449 else
450 binode->flags &= ~BTRFS_INODE_NOATIME;
451
452 /* 1 item for the inode */
453 trans = btrfs_start_transaction(root, 1);
454 if (IS_ERR(trans)) {
455 ret = PTR_ERR(trans);
456 goto out_unlock;
457 }
458
459 btrfs_sync_inode_flags_to_i_flags(inode);
460 inode_inc_iversion(inode);
461 inode->i_ctime = current_time(inode);
462 ret = btrfs_update_inode(trans, root, inode);
463
464 btrfs_end_transaction(trans);
465
466 out_unlock:
467 if (ret) {
468 binode->flags = old_flags;
469 inode->i_flags = old_i_flags;
470 }
471
472 inode_unlock(inode);
473 mnt_drop_write_file(file);
474
475 return ret;
476 }
477
478 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
479 {
480 struct inode *inode = file_inode(file);
481
482 return put_user(inode->i_generation, arg);
483 }
484
485 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
486 {
487 struct inode *inode = file_inode(file);
488 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
489 struct btrfs_device *device;
490 struct request_queue *q;
491 struct fstrim_range range;
492 u64 minlen = ULLONG_MAX;
493 u64 num_devices = 0;
494 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
495 int ret;
496
497 if (!capable(CAP_SYS_ADMIN))
498 return -EPERM;
499
500 rcu_read_lock();
501 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
502 dev_list) {
503 if (!device->bdev)
504 continue;
505 q = bdev_get_queue(device->bdev);
506 if (blk_queue_discard(q)) {
507 num_devices++;
508 minlen = min_t(u64, q->limits.discard_granularity,
509 minlen);
510 }
511 }
512 rcu_read_unlock();
513
514 if (!num_devices)
515 return -EOPNOTSUPP;
516 if (copy_from_user(&range, arg, sizeof(range)))
517 return -EFAULT;
518 if (range.start > total_bytes ||
519 range.len < fs_info->sb->s_blocksize)
520 return -EINVAL;
521
522 range.len = min(range.len, total_bytes - range.start);
523 range.minlen = max(range.minlen, minlen);
524 ret = btrfs_trim_fs(fs_info, &range);
525 if (ret < 0)
526 return ret;
527
528 if (copy_to_user(arg, &range, sizeof(range)))
529 return -EFAULT;
530
531 return 0;
532 }
533
534 int btrfs_is_empty_uuid(u8 *uuid)
535 {
536 int i;
537
538 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
539 if (uuid[i])
540 return 0;
541 }
542 return 1;
543 }
544
545 static noinline int create_subvol(struct inode *dir,
546 struct dentry *dentry,
547 const char *name, int namelen,
548 u64 *async_transid,
549 struct btrfs_qgroup_inherit *inherit)
550 {
551 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
552 struct btrfs_trans_handle *trans;
553 struct btrfs_key key;
554 struct btrfs_root_item *root_item;
555 struct btrfs_inode_item *inode_item;
556 struct extent_buffer *leaf;
557 struct btrfs_root *root = BTRFS_I(dir)->root;
558 struct btrfs_root *new_root;
559 struct btrfs_block_rsv block_rsv;
560 struct timespec64 cur_time = current_time(dir);
561 struct inode *inode;
562 int ret;
563 int err;
564 u64 objectid;
565 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
566 u64 index = 0;
567 uuid_le new_uuid;
568
569 root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
570 if (!root_item)
571 return -ENOMEM;
572
573 ret = btrfs_find_free_objectid(fs_info->tree_root, &objectid);
574 if (ret)
575 goto fail_free;
576
577 /*
578 * Don't create subvolume whose level is not zero. Or qgroup will be
579 * screwed up since it assumes subvolume qgroup's level to be 0.
580 */
581 if (btrfs_qgroup_level(objectid)) {
582 ret = -ENOSPC;
583 goto fail_free;
584 }
585
586 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
587 /*
588 * The same as the snapshot creation, please see the comment
589 * of create_snapshot().
590 */
591 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 8, false);
592 if (ret)
593 goto fail_free;
594
595 trans = btrfs_start_transaction(root, 0);
596 if (IS_ERR(trans)) {
597 ret = PTR_ERR(trans);
598 btrfs_subvolume_release_metadata(fs_info, &block_rsv);
599 goto fail_free;
600 }
601 trans->block_rsv = &block_rsv;
602 trans->bytes_reserved = block_rsv.size;
603
604 ret = btrfs_qgroup_inherit(trans, 0, objectid, inherit);
605 if (ret)
606 goto fail;
607
608 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
609 if (IS_ERR(leaf)) {
610 ret = PTR_ERR(leaf);
611 goto fail;
612 }
613
614 btrfs_mark_buffer_dirty(leaf);
615
616 inode_item = &root_item->inode;
617 btrfs_set_stack_inode_generation(inode_item, 1);
618 btrfs_set_stack_inode_size(inode_item, 3);
619 btrfs_set_stack_inode_nlink(inode_item, 1);
620 btrfs_set_stack_inode_nbytes(inode_item,
621 fs_info->nodesize);
622 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
623
624 btrfs_set_root_flags(root_item, 0);
625 btrfs_set_root_limit(root_item, 0);
626 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
627
628 btrfs_set_root_bytenr(root_item, leaf->start);
629 btrfs_set_root_generation(root_item, trans->transid);
630 btrfs_set_root_level(root_item, 0);
631 btrfs_set_root_refs(root_item, 1);
632 btrfs_set_root_used(root_item, leaf->len);
633 btrfs_set_root_last_snapshot(root_item, 0);
634
635 btrfs_set_root_generation_v2(root_item,
636 btrfs_root_generation(root_item));
637 uuid_le_gen(&new_uuid);
638 memcpy(root_item->uuid, new_uuid.b, BTRFS_UUID_SIZE);
639 btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);
640 btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);
641 root_item->ctime = root_item->otime;
642 btrfs_set_root_ctransid(root_item, trans->transid);
643 btrfs_set_root_otransid(root_item, trans->transid);
644
645 btrfs_tree_unlock(leaf);
646 free_extent_buffer(leaf);
647 leaf = NULL;
648
649 btrfs_set_root_dirid(root_item, new_dirid);
650
651 key.objectid = objectid;
652 key.offset = 0;
653 key.type = BTRFS_ROOT_ITEM_KEY;
654 ret = btrfs_insert_root(trans, fs_info->tree_root, &key,
655 root_item);
656 if (ret)
657 goto fail;
658
659 key.offset = (u64)-1;
660 new_root = btrfs_read_fs_root_no_name(fs_info, &key);
661 if (IS_ERR(new_root)) {
662 ret = PTR_ERR(new_root);
663 btrfs_abort_transaction(trans, ret);
664 goto fail;
665 }
666
667 btrfs_record_root_in_trans(trans, new_root);
668
669 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
670 if (ret) {
671 /* We potentially lose an unused inode item here */
672 btrfs_abort_transaction(trans, ret);
673 goto fail;
674 }
675
676 mutex_lock(&new_root->objectid_mutex);
677 new_root->highest_objectid = new_dirid;
678 mutex_unlock(&new_root->objectid_mutex);
679
680 /*
681 * insert the directory item
682 */
683 ret = btrfs_set_inode_index(BTRFS_I(dir), &index);
684 if (ret) {
685 btrfs_abort_transaction(trans, ret);
686 goto fail;
687 }
688
689 ret = btrfs_insert_dir_item(trans, root,
690 name, namelen, BTRFS_I(dir), &key,
691 BTRFS_FT_DIR, index);
692 if (ret) {
693 btrfs_abort_transaction(trans, ret);
694 goto fail;
695 }
696
697 btrfs_i_size_write(BTRFS_I(dir), dir->i_size + namelen * 2);
698 ret = btrfs_update_inode(trans, root, dir);
699 BUG_ON(ret);
700
701 ret = btrfs_add_root_ref(trans, objectid, root->root_key.objectid,
702 btrfs_ino(BTRFS_I(dir)), index, name, namelen);
703 BUG_ON(ret);
704
705 ret = btrfs_uuid_tree_add(trans, root_item->uuid,
706 BTRFS_UUID_KEY_SUBVOL, objectid);
707 if (ret)
708 btrfs_abort_transaction(trans, ret);
709
710 fail:
711 kfree(root_item);
712 trans->block_rsv = NULL;
713 trans->bytes_reserved = 0;
714 btrfs_subvolume_release_metadata(fs_info, &block_rsv);
715
716 if (async_transid) {
717 *async_transid = trans->transid;
718 err = btrfs_commit_transaction_async(trans, 1);
719 if (err)
720 err = btrfs_commit_transaction(trans);
721 } else {
722 err = btrfs_commit_transaction(trans);
723 }
724 if (err && !ret)
725 ret = err;
726
727 if (!ret) {
728 inode = btrfs_lookup_dentry(dir, dentry);
729 if (IS_ERR(inode))
730 return PTR_ERR(inode);
731 d_instantiate(dentry, inode);
732 }
733 return ret;
734
735 fail_free:
736 kfree(root_item);
737 return ret;
738 }
739
740 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
741 struct dentry *dentry,
742 u64 *async_transid, bool readonly,
743 struct btrfs_qgroup_inherit *inherit)
744 {
745 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
746 struct inode *inode;
747 struct btrfs_pending_snapshot *pending_snapshot;
748 struct btrfs_trans_handle *trans;
749 int ret;
750 bool snapshot_force_cow = false;
751
752 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
753 return -EINVAL;
754
755 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL);
756 if (!pending_snapshot)
757 return -ENOMEM;
758
759 pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
760 GFP_KERNEL);
761 pending_snapshot->path = btrfs_alloc_path();
762 if (!pending_snapshot->root_item || !pending_snapshot->path) {
763 ret = -ENOMEM;
764 goto free_pending;
765 }
766
767 /*
768 * Force new buffered writes to reserve space even when NOCOW is
769 * possible. This is to avoid later writeback (running dealloc) to
770 * fallback to COW mode and unexpectedly fail with ENOSPC.
771 */
772 atomic_inc(&root->will_be_snapshotted);
773 smp_mb__after_atomic();
774 /* wait for no snapshot writes */
775 wait_event(root->subv_writers->wait,
776 percpu_counter_sum(&root->subv_writers->counter) == 0);
777
778 ret = btrfs_start_delalloc_inodes(root);
779 if (ret)
780 goto dec_and_free;
781
782 /*
783 * All previous writes have started writeback in NOCOW mode, so now
784 * we force future writes to fallback to COW mode during snapshot
785 * creation.
786 */
787 atomic_inc(&root->snapshot_force_cow);
788 snapshot_force_cow = true;
789
790 btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
791
792 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
793 BTRFS_BLOCK_RSV_TEMP);
794 /*
795 * 1 - parent dir inode
796 * 2 - dir entries
797 * 1 - root item
798 * 2 - root ref/backref
799 * 1 - root of snapshot
800 * 1 - UUID item
801 */
802 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
803 &pending_snapshot->block_rsv, 8,
804 false);
805 if (ret)
806 goto dec_and_free;
807
808 pending_snapshot->dentry = dentry;
809 pending_snapshot->root = root;
810 pending_snapshot->readonly = readonly;
811 pending_snapshot->dir = dir;
812 pending_snapshot->inherit = inherit;
813
814 trans = btrfs_start_transaction(root, 0);
815 if (IS_ERR(trans)) {
816 ret = PTR_ERR(trans);
817 goto fail;
818 }
819
820 spin_lock(&fs_info->trans_lock);
821 list_add(&pending_snapshot->list,
822 &trans->transaction->pending_snapshots);
823 spin_unlock(&fs_info->trans_lock);
824 if (async_transid) {
825 *async_transid = trans->transid;
826 ret = btrfs_commit_transaction_async(trans, 1);
827 if (ret)
828 ret = btrfs_commit_transaction(trans);
829 } else {
830 ret = btrfs_commit_transaction(trans);
831 }
832 if (ret)
833 goto fail;
834
835 ret = pending_snapshot->error;
836 if (ret)
837 goto fail;
838
839 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
840 if (ret)
841 goto fail;
842
843 inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
844 if (IS_ERR(inode)) {
845 ret = PTR_ERR(inode);
846 goto fail;
847 }
848
849 d_instantiate(dentry, inode);
850 ret = 0;
851 fail:
852 btrfs_subvolume_release_metadata(fs_info, &pending_snapshot->block_rsv);
853 dec_and_free:
854 if (snapshot_force_cow)
855 atomic_dec(&root->snapshot_force_cow);
856 if (atomic_dec_and_test(&root->will_be_snapshotted))
857 wake_up_var(&root->will_be_snapshotted);
858 free_pending:
859 kfree(pending_snapshot->root_item);
860 btrfs_free_path(pending_snapshot->path);
861 kfree(pending_snapshot);
862
863 return ret;
864 }
865
866 /* copy of may_delete in fs/namei.c()
867 * Check whether we can remove a link victim from directory dir, check
868 * whether the type of victim is right.
869 * 1. We can't do it if dir is read-only (done in permission())
870 * 2. We should have write and exec permissions on dir
871 * 3. We can't remove anything from append-only dir
872 * 4. We can't do anything with immutable dir (done in permission())
873 * 5. If the sticky bit on dir is set we should either
874 * a. be owner of dir, or
875 * b. be owner of victim, or
876 * c. have CAP_FOWNER capability
877 * 6. If the victim is append-only or immutable we can't do anything with
878 * links pointing to it.
879 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
880 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
881 * 9. We can't remove a root or mountpoint.
882 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
883 * nfs_async_unlink().
884 */
885
886 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
887 {
888 int error;
889
890 if (d_really_is_negative(victim))
891 return -ENOENT;
892
893 BUG_ON(d_inode(victim->d_parent) != dir);
894 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
895
896 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
897 if (error)
898 return error;
899 if (IS_APPEND(dir))
900 return -EPERM;
901 if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
902 IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
903 return -EPERM;
904 if (isdir) {
905 if (!d_is_dir(victim))
906 return -ENOTDIR;
907 if (IS_ROOT(victim))
908 return -EBUSY;
909 } else if (d_is_dir(victim))
910 return -EISDIR;
911 if (IS_DEADDIR(dir))
912 return -ENOENT;
913 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
914 return -EBUSY;
915 return 0;
916 }
917
918 /* copy of may_create in fs/namei.c() */
919 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
920 {
921 if (d_really_is_positive(child))
922 return -EEXIST;
923 if (IS_DEADDIR(dir))
924 return -ENOENT;
925 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
926 }
927
928 /*
929 * Create a new subvolume below @parent. This is largely modeled after
930 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
931 * inside this filesystem so it's quite a bit simpler.
932 */
933 static noinline int btrfs_mksubvol(const struct path *parent,
934 const char *name, int namelen,
935 struct btrfs_root *snap_src,
936 u64 *async_transid, bool readonly,
937 struct btrfs_qgroup_inherit *inherit)
938 {
939 struct inode *dir = d_inode(parent->dentry);
940 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
941 struct dentry *dentry;
942 int error;
943
944 error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
945 if (error == -EINTR)
946 return error;
947
948 dentry = lookup_one_len(name, parent->dentry, namelen);
949 error = PTR_ERR(dentry);
950 if (IS_ERR(dentry))
951 goto out_unlock;
952
953 error = btrfs_may_create(dir, dentry);
954 if (error)
955 goto out_dput;
956
957 /*
958 * even if this name doesn't exist, we may get hash collisions.
959 * check for them now when we can safely fail
960 */
961 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
962 dir->i_ino, name,
963 namelen);
964 if (error)
965 goto out_dput;
966
967 down_read(&fs_info->subvol_sem);
968
969 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
970 goto out_up_read;
971
972 if (snap_src) {
973 error = create_snapshot(snap_src, dir, dentry,
974 async_transid, readonly, inherit);
975 } else {
976 error = create_subvol(dir, dentry, name, namelen,
977 async_transid, inherit);
978 }
979 if (!error)
980 fsnotify_mkdir(dir, dentry);
981 out_up_read:
982 up_read(&fs_info->subvol_sem);
983 out_dput:
984 dput(dentry);
985 out_unlock:
986 inode_unlock(dir);
987 return error;
988 }
989
990 /*
991 * When we're defragging a range, we don't want to kick it off again
992 * if it is really just waiting for delalloc to send it down.
993 * If we find a nice big extent or delalloc range for the bytes in the
994 * file you want to defrag, we return 0 to let you know to skip this
995 * part of the file
996 */
997 static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
998 {
999 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1000 struct extent_map *em = NULL;
1001 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1002 u64 end;
1003
1004 read_lock(&em_tree->lock);
1005 em = lookup_extent_mapping(em_tree, offset, PAGE_SIZE);
1006 read_unlock(&em_tree->lock);
1007
1008 if (em) {
1009 end = extent_map_end(em);
1010 free_extent_map(em);
1011 if (end - offset > thresh)
1012 return 0;
1013 }
1014 /* if we already have a nice delalloc here, just stop */
1015 thresh /= 2;
1016 end = count_range_bits(io_tree, &offset, offset + thresh,
1017 thresh, EXTENT_DELALLOC, 1);
1018 if (end >= thresh)
1019 return 0;
1020 return 1;
1021 }
1022
1023 /*
1024 * helper function to walk through a file and find extents
1025 * newer than a specific transid, and smaller than thresh.
1026 *
1027 * This is used by the defragging code to find new and small
1028 * extents
1029 */
1030 static int find_new_extents(struct btrfs_root *root,
1031 struct inode *inode, u64 newer_than,
1032 u64 *off, u32 thresh)
1033 {
1034 struct btrfs_path *path;
1035 struct btrfs_key min_key;
1036 struct extent_buffer *leaf;
1037 struct btrfs_file_extent_item *extent;
1038 int type;
1039 int ret;
1040 u64 ino = btrfs_ino(BTRFS_I(inode));
1041
1042 path = btrfs_alloc_path();
1043 if (!path)
1044 return -ENOMEM;
1045
1046 min_key.objectid = ino;
1047 min_key.type = BTRFS_EXTENT_DATA_KEY;
1048 min_key.offset = *off;
1049
1050 while (1) {
1051 ret = btrfs_search_forward(root, &min_key, path, newer_than);
1052 if (ret != 0)
1053 goto none;
1054 process_slot:
1055 if (min_key.objectid != ino)
1056 goto none;
1057 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
1058 goto none;
1059
1060 leaf = path->nodes[0];
1061 extent = btrfs_item_ptr(leaf, path->slots[0],
1062 struct btrfs_file_extent_item);
1063
1064 type = btrfs_file_extent_type(leaf, extent);
1065 if (type == BTRFS_FILE_EXTENT_REG &&
1066 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
1067 check_defrag_in_cache(inode, min_key.offset, thresh)) {
1068 *off = min_key.offset;
1069 btrfs_free_path(path);
1070 return 0;
1071 }
1072
1073 path->slots[0]++;
1074 if (path->slots[0] < btrfs_header_nritems(leaf)) {
1075 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
1076 goto process_slot;
1077 }
1078
1079 if (min_key.offset == (u64)-1)
1080 goto none;
1081
1082 min_key.offset++;
1083 btrfs_release_path(path);
1084 }
1085 none:
1086 btrfs_free_path(path);
1087 return -ENOENT;
1088 }
1089
1090 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
1091 {
1092 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1093 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1094 struct extent_map *em;
1095 u64 len = PAGE_SIZE;
1096
1097 /*
1098 * hopefully we have this extent in the tree already, try without
1099 * the full extent lock
1100 */
1101 read_lock(&em_tree->lock);
1102 em = lookup_extent_mapping(em_tree, start, len);
1103 read_unlock(&em_tree->lock);
1104
1105 if (!em) {
1106 struct extent_state *cached = NULL;
1107 u64 end = start + len - 1;
1108
1109 /* get the big lock and read metadata off disk */
1110 lock_extent_bits(io_tree, start, end, &cached);
1111 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len, 0);
1112 unlock_extent_cached(io_tree, start, end, &cached);
1113
1114 if (IS_ERR(em))
1115 return NULL;
1116 }
1117
1118 return em;
1119 }
1120
1121 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1122 {
1123 struct extent_map *next;
1124 bool ret = true;
1125
1126 /* this is the last extent */
1127 if (em->start + em->len >= i_size_read(inode))
1128 return false;
1129
1130 next = defrag_lookup_extent(inode, em->start + em->len);
1131 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1132 ret = false;
1133 else if ((em->block_start + em->block_len == next->block_start) &&
1134 (em->block_len > SZ_128K && next->block_len > SZ_128K))
1135 ret = false;
1136
1137 free_extent_map(next);
1138 return ret;
1139 }
1140
1141 static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1142 u64 *last_len, u64 *skip, u64 *defrag_end,
1143 int compress)
1144 {
1145 struct extent_map *em;
1146 int ret = 1;
1147 bool next_mergeable = true;
1148 bool prev_mergeable = true;
1149
1150 /*
1151 * make sure that once we start defragging an extent, we keep on
1152 * defragging it
1153 */
1154 if (start < *defrag_end)
1155 return 1;
1156
1157 *skip = 0;
1158
1159 em = defrag_lookup_extent(inode, start);
1160 if (!em)
1161 return 0;
1162
1163 /* this will cover holes, and inline extents */
1164 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1165 ret = 0;
1166 goto out;
1167 }
1168
1169 if (!*defrag_end)
1170 prev_mergeable = false;
1171
1172 next_mergeable = defrag_check_next_extent(inode, em);
1173 /*
1174 * we hit a real extent, if it is big or the next extent is not a
1175 * real extent, don't bother defragging it
1176 */
1177 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1178 (em->len >= thresh || (!next_mergeable && !prev_mergeable)))
1179 ret = 0;
1180 out:
1181 /*
1182 * last_len ends up being a counter of how many bytes we've defragged.
1183 * every time we choose not to defrag an extent, we reset *last_len
1184 * so that the next tiny extent will force a defrag.
1185 *
1186 * The end result of this is that tiny extents before a single big
1187 * extent will force at least part of that big extent to be defragged.
1188 */
1189 if (ret) {
1190 *defrag_end = extent_map_end(em);
1191 } else {
1192 *last_len = 0;
1193 *skip = extent_map_end(em);
1194 *defrag_end = 0;
1195 }
1196
1197 free_extent_map(em);
1198 return ret;
1199 }
1200
1201 /*
1202 * it doesn't do much good to defrag one or two pages
1203 * at a time. This pulls in a nice chunk of pages
1204 * to COW and defrag.
1205 *
1206 * It also makes sure the delalloc code has enough
1207 * dirty data to avoid making new small extents as part
1208 * of the defrag
1209 *
1210 * It's a good idea to start RA on this range
1211 * before calling this.
1212 */
1213 static int cluster_pages_for_defrag(struct inode *inode,
1214 struct page **pages,
1215 unsigned long start_index,
1216 unsigned long num_pages)
1217 {
1218 unsigned long file_end;
1219 u64 isize = i_size_read(inode);
1220 u64 page_start;
1221 u64 page_end;
1222 u64 page_cnt;
1223 int ret;
1224 int i;
1225 int i_done;
1226 struct btrfs_ordered_extent *ordered;
1227 struct extent_state *cached_state = NULL;
1228 struct extent_io_tree *tree;
1229 struct extent_changeset *data_reserved = NULL;
1230 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1231
1232 file_end = (isize - 1) >> PAGE_SHIFT;
1233 if (!isize || start_index > file_end)
1234 return 0;
1235
1236 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1237
1238 ret = btrfs_delalloc_reserve_space(inode, &data_reserved,
1239 start_index << PAGE_SHIFT,
1240 page_cnt << PAGE_SHIFT);
1241 if (ret)
1242 return ret;
1243 i_done = 0;
1244 tree = &BTRFS_I(inode)->io_tree;
1245
1246 /* step one, lock all the pages */
1247 for (i = 0; i < page_cnt; i++) {
1248 struct page *page;
1249 again:
1250 page = find_or_create_page(inode->i_mapping,
1251 start_index + i, mask);
1252 if (!page)
1253 break;
1254
1255 page_start = page_offset(page);
1256 page_end = page_start + PAGE_SIZE - 1;
1257 while (1) {
1258 lock_extent_bits(tree, page_start, page_end,
1259 &cached_state);
1260 ordered = btrfs_lookup_ordered_extent(inode,
1261 page_start);
1262 unlock_extent_cached(tree, page_start, page_end,
1263 &cached_state);
1264 if (!ordered)
1265 break;
1266
1267 unlock_page(page);
1268 btrfs_start_ordered_extent(inode, ordered, 1);
1269 btrfs_put_ordered_extent(ordered);
1270 lock_page(page);
1271 /*
1272 * we unlocked the page above, so we need check if
1273 * it was released or not.
1274 */
1275 if (page->mapping != inode->i_mapping) {
1276 unlock_page(page);
1277 put_page(page);
1278 goto again;
1279 }
1280 }
1281
1282 if (!PageUptodate(page)) {
1283 btrfs_readpage(NULL, page);
1284 lock_page(page);
1285 if (!PageUptodate(page)) {
1286 unlock_page(page);
1287 put_page(page);
1288 ret = -EIO;
1289 break;
1290 }
1291 }
1292
1293 if (page->mapping != inode->i_mapping) {
1294 unlock_page(page);
1295 put_page(page);
1296 goto again;
1297 }
1298
1299 pages[i] = page;
1300 i_done++;
1301 }
1302 if (!i_done || ret)
1303 goto out;
1304
1305 if (!(inode->i_sb->s_flags & SB_ACTIVE))
1306 goto out;
1307
1308 /*
1309 * so now we have a nice long stream of locked
1310 * and up to date pages, lets wait on them
1311 */
1312 for (i = 0; i < i_done; i++)
1313 wait_on_page_writeback(pages[i]);
1314
1315 page_start = page_offset(pages[0]);
1316 page_end = page_offset(pages[i_done - 1]) + PAGE_SIZE;
1317
1318 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1319 page_start, page_end - 1, &cached_state);
1320 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1321 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1322 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1323 &cached_state);
1324
1325 if (i_done != page_cnt) {
1326 spin_lock(&BTRFS_I(inode)->lock);
1327 BTRFS_I(inode)->outstanding_extents++;
1328 spin_unlock(&BTRFS_I(inode)->lock);
1329 btrfs_delalloc_release_space(inode, data_reserved,
1330 start_index << PAGE_SHIFT,
1331 (page_cnt - i_done) << PAGE_SHIFT, true);
1332 }
1333
1334
1335 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1336 &cached_state);
1337
1338 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1339 page_start, page_end - 1, &cached_state);
1340
1341 for (i = 0; i < i_done; i++) {
1342 clear_page_dirty_for_io(pages[i]);
1343 ClearPageChecked(pages[i]);
1344 set_page_extent_mapped(pages[i]);
1345 set_page_dirty(pages[i]);
1346 unlock_page(pages[i]);
1347 put_page(pages[i]);
1348 }
1349 btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT,
1350 false);
1351 extent_changeset_free(data_reserved);
1352 return i_done;
1353 out:
1354 for (i = 0; i < i_done; i++) {
1355 unlock_page(pages[i]);
1356 put_page(pages[i]);
1357 }
1358 btrfs_delalloc_release_space(inode, data_reserved,
1359 start_index << PAGE_SHIFT,
1360 page_cnt << PAGE_SHIFT, true);
1361 btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT,
1362 true);
1363 extent_changeset_free(data_reserved);
1364 return ret;
1365
1366 }
1367
1368 int btrfs_defrag_file(struct inode *inode, struct file *file,
1369 struct btrfs_ioctl_defrag_range_args *range,
1370 u64 newer_than, unsigned long max_to_defrag)
1371 {
1372 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1373 struct btrfs_root *root = BTRFS_I(inode)->root;
1374 struct file_ra_state *ra = NULL;
1375 unsigned long last_index;
1376 u64 isize = i_size_read(inode);
1377 u64 last_len = 0;
1378 u64 skip = 0;
1379 u64 defrag_end = 0;
1380 u64 newer_off = range->start;
1381 unsigned long i;
1382 unsigned long ra_index = 0;
1383 int ret;
1384 int defrag_count = 0;
1385 int compress_type = BTRFS_COMPRESS_ZLIB;
1386 u32 extent_thresh = range->extent_thresh;
1387 unsigned long max_cluster = SZ_256K >> PAGE_SHIFT;
1388 unsigned long cluster = max_cluster;
1389 u64 new_align = ~((u64)SZ_128K - 1);
1390 struct page **pages = NULL;
1391 bool do_compress = range->flags & BTRFS_DEFRAG_RANGE_COMPRESS;
1392
1393 if (isize == 0)
1394 return 0;
1395
1396 if (range->start >= isize)
1397 return -EINVAL;
1398
1399 if (do_compress) {
1400 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1401 return -EINVAL;
1402 if (range->compress_type)
1403 compress_type = range->compress_type;
1404 }
1405
1406 if (extent_thresh == 0)
1407 extent_thresh = SZ_256K;
1408
1409 /*
1410 * If we were not given a file, allocate a readahead context. As
1411 * readahead is just an optimization, defrag will work without it so
1412 * we don't error out.
1413 */
1414 if (!file) {
1415 ra = kzalloc(sizeof(*ra), GFP_KERNEL);
1416 if (ra)
1417 file_ra_state_init(ra, inode->i_mapping);
1418 } else {
1419 ra = &file->f_ra;
1420 }
1421
1422 pages = kmalloc_array(max_cluster, sizeof(struct page *), GFP_KERNEL);
1423 if (!pages) {
1424 ret = -ENOMEM;
1425 goto out_ra;
1426 }
1427
1428 /* find the last page to defrag */
1429 if (range->start + range->len > range->start) {
1430 last_index = min_t(u64, isize - 1,
1431 range->start + range->len - 1) >> PAGE_SHIFT;
1432 } else {
1433 last_index = (isize - 1) >> PAGE_SHIFT;
1434 }
1435
1436 if (newer_than) {
1437 ret = find_new_extents(root, inode, newer_than,
1438 &newer_off, SZ_64K);
1439 if (!ret) {
1440 range->start = newer_off;
1441 /*
1442 * we always align our defrag to help keep
1443 * the extents in the file evenly spaced
1444 */
1445 i = (newer_off & new_align) >> PAGE_SHIFT;
1446 } else
1447 goto out_ra;
1448 } else {
1449 i = range->start >> PAGE_SHIFT;
1450 }
1451 if (!max_to_defrag)
1452 max_to_defrag = last_index - i + 1;
1453
1454 /*
1455 * make writeback starts from i, so the defrag range can be
1456 * written sequentially.
1457 */
1458 if (i < inode->i_mapping->writeback_index)
1459 inode->i_mapping->writeback_index = i;
1460
1461 while (i <= last_index && defrag_count < max_to_defrag &&
1462 (i < DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE))) {
1463 /*
1464 * make sure we stop running if someone unmounts
1465 * the FS
1466 */
1467 if (!(inode->i_sb->s_flags & SB_ACTIVE))
1468 break;
1469
1470 if (btrfs_defrag_cancelled(fs_info)) {
1471 btrfs_debug(fs_info, "defrag_file cancelled");
1472 ret = -EAGAIN;
1473 break;
1474 }
1475
1476 if (!should_defrag_range(inode, (u64)i << PAGE_SHIFT,
1477 extent_thresh, &last_len, &skip,
1478 &defrag_end, do_compress)){
1479 unsigned long next;
1480 /*
1481 * the should_defrag function tells us how much to skip
1482 * bump our counter by the suggested amount
1483 */
1484 next = DIV_ROUND_UP(skip, PAGE_SIZE);
1485 i = max(i + 1, next);
1486 continue;
1487 }
1488
1489 if (!newer_than) {
1490 cluster = (PAGE_ALIGN(defrag_end) >>
1491 PAGE_SHIFT) - i;
1492 cluster = min(cluster, max_cluster);
1493 } else {
1494 cluster = max_cluster;
1495 }
1496
1497 if (i + cluster > ra_index) {
1498 ra_index = max(i, ra_index);
1499 if (ra)
1500 page_cache_sync_readahead(inode->i_mapping, ra,
1501 file, ra_index, cluster);
1502 ra_index += cluster;
1503 }
1504
1505 inode_lock(inode);
1506 if (do_compress)
1507 BTRFS_I(inode)->defrag_compress = compress_type;
1508 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1509 if (ret < 0) {
1510 inode_unlock(inode);
1511 goto out_ra;
1512 }
1513
1514 defrag_count += ret;
1515 balance_dirty_pages_ratelimited(inode->i_mapping);
1516 inode_unlock(inode);
1517
1518 if (newer_than) {
1519 if (newer_off == (u64)-1)
1520 break;
1521
1522 if (ret > 0)
1523 i += ret;
1524
1525 newer_off = max(newer_off + 1,
1526 (u64)i << PAGE_SHIFT);
1527
1528 ret = find_new_extents(root, inode, newer_than,
1529 &newer_off, SZ_64K);
1530 if (!ret) {
1531 range->start = newer_off;
1532 i = (newer_off & new_align) >> PAGE_SHIFT;
1533 } else {
1534 break;
1535 }
1536 } else {
1537 if (ret > 0) {
1538 i += ret;
1539 last_len += ret << PAGE_SHIFT;
1540 } else {
1541 i++;
1542 last_len = 0;
1543 }
1544 }
1545 }
1546
1547 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1548 filemap_flush(inode->i_mapping);
1549 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1550 &BTRFS_I(inode)->runtime_flags))
1551 filemap_flush(inode->i_mapping);
1552 }
1553
1554 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1555 btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
1556 } else if (range->compress_type == BTRFS_COMPRESS_ZSTD) {
1557 btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
1558 }
1559
1560 ret = defrag_count;
1561
1562 out_ra:
1563 if (do_compress) {
1564 inode_lock(inode);
1565 BTRFS_I(inode)->defrag_compress = BTRFS_COMPRESS_NONE;
1566 inode_unlock(inode);
1567 }
1568 if (!file)
1569 kfree(ra);
1570 kfree(pages);
1571 return ret;
1572 }
1573
1574 static noinline int btrfs_ioctl_resize(struct file *file,
1575 void __user *arg)
1576 {
1577 struct inode *inode = file_inode(file);
1578 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1579 u64 new_size;
1580 u64 old_size;
1581 u64 devid = 1;
1582 struct btrfs_root *root = BTRFS_I(inode)->root;
1583 struct btrfs_ioctl_vol_args *vol_args;
1584 struct btrfs_trans_handle *trans;
1585 struct btrfs_device *device = NULL;
1586 char *sizestr;
1587 char *retptr;
1588 char *devstr = NULL;
1589 int ret = 0;
1590 int mod = 0;
1591
1592 if (!capable(CAP_SYS_ADMIN))
1593 return -EPERM;
1594
1595 ret = mnt_want_write_file(file);
1596 if (ret)
1597 return ret;
1598
1599 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
1600 mnt_drop_write_file(file);
1601 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1602 }
1603
1604 vol_args = memdup_user(arg, sizeof(*vol_args));
1605 if (IS_ERR(vol_args)) {
1606 ret = PTR_ERR(vol_args);
1607 goto out;
1608 }
1609
1610 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1611
1612 sizestr = vol_args->name;
1613 devstr = strchr(sizestr, ':');
1614 if (devstr) {
1615 sizestr = devstr + 1;
1616 *devstr = '\0';
1617 devstr = vol_args->name;
1618 ret = kstrtoull(devstr, 10, &devid);
1619 if (ret)
1620 goto out_free;
1621 if (!devid) {
1622 ret = -EINVAL;
1623 goto out_free;
1624 }
1625 btrfs_info(fs_info, "resizing devid %llu", devid);
1626 }
1627
1628 device = btrfs_find_device(fs_info, devid, NULL, NULL);
1629 if (!device) {
1630 btrfs_info(fs_info, "resizer unable to find device %llu",
1631 devid);
1632 ret = -ENODEV;
1633 goto out_free;
1634 }
1635
1636 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
1637 btrfs_info(fs_info,
1638 "resizer unable to apply on readonly device %llu",
1639 devid);
1640 ret = -EPERM;
1641 goto out_free;
1642 }
1643
1644 if (!strcmp(sizestr, "max"))
1645 new_size = device->bdev->bd_inode->i_size;
1646 else {
1647 if (sizestr[0] == '-') {
1648 mod = -1;
1649 sizestr++;
1650 } else if (sizestr[0] == '+') {
1651 mod = 1;
1652 sizestr++;
1653 }
1654 new_size = memparse(sizestr, &retptr);
1655 if (*retptr != '\0' || new_size == 0) {
1656 ret = -EINVAL;
1657 goto out_free;
1658 }
1659 }
1660
1661 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
1662 ret = -EPERM;
1663 goto out_free;
1664 }
1665
1666 old_size = btrfs_device_get_total_bytes(device);
1667
1668 if (mod < 0) {
1669 if (new_size > old_size) {
1670 ret = -EINVAL;
1671 goto out_free;
1672 }
1673 new_size = old_size - new_size;
1674 } else if (mod > 0) {
1675 if (new_size > ULLONG_MAX - old_size) {
1676 ret = -ERANGE;
1677 goto out_free;
1678 }
1679 new_size = old_size + new_size;
1680 }
1681
1682 if (new_size < SZ_256M) {
1683 ret = -EINVAL;
1684 goto out_free;
1685 }
1686 if (new_size > device->bdev->bd_inode->i_size) {
1687 ret = -EFBIG;
1688 goto out_free;
1689 }
1690
1691 new_size = round_down(new_size, fs_info->sectorsize);
1692
1693 btrfs_info_in_rcu(fs_info, "new size for %s is %llu",
1694 rcu_str_deref(device->name), new_size);
1695
1696 if (new_size > old_size) {
1697 trans = btrfs_start_transaction(root, 0);
1698 if (IS_ERR(trans)) {
1699 ret = PTR_ERR(trans);
1700 goto out_free;
1701 }
1702 ret = btrfs_grow_device(trans, device, new_size);
1703 btrfs_commit_transaction(trans);
1704 } else if (new_size < old_size) {
1705 ret = btrfs_shrink_device(device, new_size);
1706 } /* equal, nothing need to do */
1707
1708 out_free:
1709 kfree(vol_args);
1710 out:
1711 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
1712 mnt_drop_write_file(file);
1713 return ret;
1714 }
1715
1716 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1717 const char *name, unsigned long fd, int subvol,
1718 u64 *transid, bool readonly,
1719 struct btrfs_qgroup_inherit *inherit)
1720 {
1721 int namelen;
1722 int ret = 0;
1723
1724 if (!S_ISDIR(file_inode(file)->i_mode))
1725 return -ENOTDIR;
1726
1727 ret = mnt_want_write_file(file);
1728 if (ret)
1729 goto out;
1730
1731 namelen = strlen(name);
1732 if (strchr(name, '/')) {
1733 ret = -EINVAL;
1734 goto out_drop_write;
1735 }
1736
1737 if (name[0] == '.' &&
1738 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1739 ret = -EEXIST;
1740 goto out_drop_write;
1741 }
1742
1743 if (subvol) {
1744 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1745 NULL, transid, readonly, inherit);
1746 } else {
1747 struct fd src = fdget(fd);
1748 struct inode *src_inode;
1749 if (!src.file) {
1750 ret = -EINVAL;
1751 goto out_drop_write;
1752 }
1753
1754 src_inode = file_inode(src.file);
1755 if (src_inode->i_sb != file_inode(file)->i_sb) {
1756 btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
1757 "Snapshot src from another FS");
1758 ret = -EXDEV;
1759 } else if (!inode_owner_or_capable(src_inode)) {
1760 /*
1761 * Subvolume creation is not restricted, but snapshots
1762 * are limited to own subvolumes only
1763 */
1764 ret = -EPERM;
1765 } else {
1766 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1767 BTRFS_I(src_inode)->root,
1768 transid, readonly, inherit);
1769 }
1770 fdput(src);
1771 }
1772 out_drop_write:
1773 mnt_drop_write_file(file);
1774 out:
1775 return ret;
1776 }
1777
1778 static noinline int btrfs_ioctl_snap_create(struct file *file,
1779 void __user *arg, int subvol)
1780 {
1781 struct btrfs_ioctl_vol_args *vol_args;
1782 int ret;
1783
1784 if (!S_ISDIR(file_inode(file)->i_mode))
1785 return -ENOTDIR;
1786
1787 vol_args = memdup_user(arg, sizeof(*vol_args));
1788 if (IS_ERR(vol_args))
1789 return PTR_ERR(vol_args);
1790 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1791
1792 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1793 vol_args->fd, subvol,
1794 NULL, false, NULL);
1795
1796 kfree(vol_args);
1797 return ret;
1798 }
1799
1800 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1801 void __user *arg, int subvol)
1802 {
1803 struct btrfs_ioctl_vol_args_v2 *vol_args;
1804 int ret;
1805 u64 transid = 0;
1806 u64 *ptr = NULL;
1807 bool readonly = false;
1808 struct btrfs_qgroup_inherit *inherit = NULL;
1809
1810 if (!S_ISDIR(file_inode(file)->i_mode))
1811 return -ENOTDIR;
1812
1813 vol_args = memdup_user(arg, sizeof(*vol_args));
1814 if (IS_ERR(vol_args))
1815 return PTR_ERR(vol_args);
1816 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1817
1818 if (vol_args->flags &
1819 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1820 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1821 ret = -EOPNOTSUPP;
1822 goto free_args;
1823 }
1824
1825 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1826 ptr = &transid;
1827 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1828 readonly = true;
1829 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1830 if (vol_args->size > PAGE_SIZE) {
1831 ret = -EINVAL;
1832 goto free_args;
1833 }
1834 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1835 if (IS_ERR(inherit)) {
1836 ret = PTR_ERR(inherit);
1837 goto free_args;
1838 }
1839 }
1840
1841 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1842 vol_args->fd, subvol, ptr,
1843 readonly, inherit);
1844 if (ret)
1845 goto free_inherit;
1846
1847 if (ptr && copy_to_user(arg +
1848 offsetof(struct btrfs_ioctl_vol_args_v2,
1849 transid),
1850 ptr, sizeof(*ptr)))
1851 ret = -EFAULT;
1852
1853 free_inherit:
1854 kfree(inherit);
1855 free_args:
1856 kfree(vol_args);
1857 return ret;
1858 }
1859
1860 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1861 void __user *arg)
1862 {
1863 struct inode *inode = file_inode(file);
1864 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1865 struct btrfs_root *root = BTRFS_I(inode)->root;
1866 int ret = 0;
1867 u64 flags = 0;
1868
1869 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)
1870 return -EINVAL;
1871
1872 down_read(&fs_info->subvol_sem);
1873 if (btrfs_root_readonly(root))
1874 flags |= BTRFS_SUBVOL_RDONLY;
1875 up_read(&fs_info->subvol_sem);
1876
1877 if (copy_to_user(arg, &flags, sizeof(flags)))
1878 ret = -EFAULT;
1879
1880 return ret;
1881 }
1882
1883 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1884 void __user *arg)
1885 {
1886 struct inode *inode = file_inode(file);
1887 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1888 struct btrfs_root *root = BTRFS_I(inode)->root;
1889 struct btrfs_trans_handle *trans;
1890 u64 root_flags;
1891 u64 flags;
1892 int ret = 0;
1893
1894 if (!inode_owner_or_capable(inode))
1895 return -EPERM;
1896
1897 ret = mnt_want_write_file(file);
1898 if (ret)
1899 goto out;
1900
1901 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
1902 ret = -EINVAL;
1903 goto out_drop_write;
1904 }
1905
1906 if (copy_from_user(&flags, arg, sizeof(flags))) {
1907 ret = -EFAULT;
1908 goto out_drop_write;
1909 }
1910
1911 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1912 ret = -EINVAL;
1913 goto out_drop_write;
1914 }
1915
1916 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1917 ret = -EOPNOTSUPP;
1918 goto out_drop_write;
1919 }
1920
1921 down_write(&fs_info->subvol_sem);
1922
1923 /* nothing to do */
1924 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1925 goto out_drop_sem;
1926
1927 root_flags = btrfs_root_flags(&root->root_item);
1928 if (flags & BTRFS_SUBVOL_RDONLY) {
1929 btrfs_set_root_flags(&root->root_item,
1930 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1931 } else {
1932 /*
1933 * Block RO -> RW transition if this subvolume is involved in
1934 * send
1935 */
1936 spin_lock(&root->root_item_lock);
1937 if (root->send_in_progress == 0) {
1938 btrfs_set_root_flags(&root->root_item,
1939 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1940 spin_unlock(&root->root_item_lock);
1941 } else {
1942 spin_unlock(&root->root_item_lock);
1943 btrfs_warn(fs_info,
1944 "Attempt to set subvolume %llu read-write during send",
1945 root->root_key.objectid);
1946 ret = -EPERM;
1947 goto out_drop_sem;
1948 }
1949 }
1950
1951 trans = btrfs_start_transaction(root, 1);
1952 if (IS_ERR(trans)) {
1953 ret = PTR_ERR(trans);
1954 goto out_reset;
1955 }
1956
1957 ret = btrfs_update_root(trans, fs_info->tree_root,
1958 &root->root_key, &root->root_item);
1959 if (ret < 0) {
1960 btrfs_end_transaction(trans);
1961 goto out_reset;
1962 }
1963
1964 ret = btrfs_commit_transaction(trans);
1965
1966 out_reset:
1967 if (ret)
1968 btrfs_set_root_flags(&root->root_item, root_flags);
1969 out_drop_sem:
1970 up_write(&fs_info->subvol_sem);
1971 out_drop_write:
1972 mnt_drop_write_file(file);
1973 out:
1974 return ret;
1975 }
1976
1977 static noinline int key_in_sk(struct btrfs_key *key,
1978 struct btrfs_ioctl_search_key *sk)
1979 {
1980 struct btrfs_key test;
1981 int ret;
1982
1983 test.objectid = sk->min_objectid;
1984 test.type = sk->min_type;
1985 test.offset = sk->min_offset;
1986
1987 ret = btrfs_comp_cpu_keys(key, &test);
1988 if (ret < 0)
1989 return 0;
1990
1991 test.objectid = sk->max_objectid;
1992 test.type = sk->max_type;
1993 test.offset = sk->max_offset;
1994
1995 ret = btrfs_comp_cpu_keys(key, &test);
1996 if (ret > 0)
1997 return 0;
1998 return 1;
1999 }
2000
2001 static noinline int copy_to_sk(struct btrfs_path *path,
2002 struct btrfs_key *key,
2003 struct btrfs_ioctl_search_key *sk,
2004 size_t *buf_size,
2005 char __user *ubuf,
2006 unsigned long *sk_offset,
2007 int *num_found)
2008 {
2009 u64 found_transid;
2010 struct extent_buffer *leaf;
2011 struct btrfs_ioctl_search_header sh;
2012 struct btrfs_key test;
2013 unsigned long item_off;
2014 unsigned long item_len;
2015 int nritems;
2016 int i;
2017 int slot;
2018 int ret = 0;
2019
2020 leaf = path->nodes[0];
2021 slot = path->slots[0];
2022 nritems = btrfs_header_nritems(leaf);
2023
2024 if (btrfs_header_generation(leaf) > sk->max_transid) {
2025 i = nritems;
2026 goto advance_key;
2027 }
2028 found_transid = btrfs_header_generation(leaf);
2029
2030 for (i = slot; i < nritems; i++) {
2031 item_off = btrfs_item_ptr_offset(leaf, i);
2032 item_len = btrfs_item_size_nr(leaf, i);
2033
2034 btrfs_item_key_to_cpu(leaf, key, i);
2035 if (!key_in_sk(key, sk))
2036 continue;
2037
2038 if (sizeof(sh) + item_len > *buf_size) {
2039 if (*num_found) {
2040 ret = 1;
2041 goto out;
2042 }
2043
2044 /*
2045 * return one empty item back for v1, which does not
2046 * handle -EOVERFLOW
2047 */
2048
2049 *buf_size = sizeof(sh) + item_len;
2050 item_len = 0;
2051 ret = -EOVERFLOW;
2052 }
2053
2054 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2055 ret = 1;
2056 goto out;
2057 }
2058
2059 sh.objectid = key->objectid;
2060 sh.offset = key->offset;
2061 sh.type = key->type;
2062 sh.len = item_len;
2063 sh.transid = found_transid;
2064
2065 /* copy search result header */
2066 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
2067 ret = -EFAULT;
2068 goto out;
2069 }
2070
2071 *sk_offset += sizeof(sh);
2072
2073 if (item_len) {
2074 char __user *up = ubuf + *sk_offset;
2075 /* copy the item */
2076 if (read_extent_buffer_to_user(leaf, up,
2077 item_off, item_len)) {
2078 ret = -EFAULT;
2079 goto out;
2080 }
2081
2082 *sk_offset += item_len;
2083 }
2084 (*num_found)++;
2085
2086 if (ret) /* -EOVERFLOW from above */
2087 goto out;
2088
2089 if (*num_found >= sk->nr_items) {
2090 ret = 1;
2091 goto out;
2092 }
2093 }
2094 advance_key:
2095 ret = 0;
2096 test.objectid = sk->max_objectid;
2097 test.type = sk->max_type;
2098 test.offset = sk->max_offset;
2099 if (btrfs_comp_cpu_keys(key, &test) >= 0)
2100 ret = 1;
2101 else if (key->offset < (u64)-1)
2102 key->offset++;
2103 else if (key->type < (u8)-1) {
2104 key->offset = 0;
2105 key->type++;
2106 } else if (key->objectid < (u64)-1) {
2107 key->offset = 0;
2108 key->type = 0;
2109 key->objectid++;
2110 } else
2111 ret = 1;
2112 out:
2113 /*
2114 * 0: all items from this leaf copied, continue with next
2115 * 1: * more items can be copied, but unused buffer is too small
2116 * * all items were found
2117 * Either way, it will stops the loop which iterates to the next
2118 * leaf
2119 * -EOVERFLOW: item was to large for buffer
2120 * -EFAULT: could not copy extent buffer back to userspace
2121 */
2122 return ret;
2123 }
2124
2125 static noinline int search_ioctl(struct inode *inode,
2126 struct btrfs_ioctl_search_key *sk,
2127 size_t *buf_size,
2128 char __user *ubuf)
2129 {
2130 struct btrfs_fs_info *info = btrfs_sb(inode->i_sb);
2131 struct btrfs_root *root;
2132 struct btrfs_key key;
2133 struct btrfs_path *path;
2134 int ret;
2135 int num_found = 0;
2136 unsigned long sk_offset = 0;
2137
2138 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2139 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2140 return -EOVERFLOW;
2141 }
2142
2143 path = btrfs_alloc_path();
2144 if (!path)
2145 return -ENOMEM;
2146
2147 if (sk->tree_id == 0) {
2148 /* search the root of the inode that was passed */
2149 root = BTRFS_I(inode)->root;
2150 } else {
2151 key.objectid = sk->tree_id;
2152 key.type = BTRFS_ROOT_ITEM_KEY;
2153 key.offset = (u64)-1;
2154 root = btrfs_read_fs_root_no_name(info, &key);
2155 if (IS_ERR(root)) {
2156 btrfs_free_path(path);
2157 return PTR_ERR(root);
2158 }
2159 }
2160
2161 key.objectid = sk->min_objectid;
2162 key.type = sk->min_type;
2163 key.offset = sk->min_offset;
2164
2165 while (1) {
2166 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2167 if (ret != 0) {
2168 if (ret > 0)
2169 ret = 0;
2170 goto err;
2171 }
2172 ret = copy_to_sk(path, &key, sk, buf_size, ubuf,
2173 &sk_offset, &num_found);
2174 btrfs_release_path(path);
2175 if (ret)
2176 break;
2177
2178 }
2179 if (ret > 0)
2180 ret = 0;
2181 err:
2182 sk->nr_items = num_found;
2183 btrfs_free_path(path);
2184 return ret;
2185 }
2186
2187 static noinline int btrfs_ioctl_tree_search(struct file *file,
2188 void __user *argp)
2189 {
2190 struct btrfs_ioctl_search_args __user *uargs;
2191 struct btrfs_ioctl_search_key sk;
2192 struct inode *inode;
2193 int ret;
2194 size_t buf_size;
2195
2196 if (!capable(CAP_SYS_ADMIN))
2197 return -EPERM;
2198
2199 uargs = (struct btrfs_ioctl_search_args __user *)argp;
2200
2201 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2202 return -EFAULT;
2203
2204 buf_size = sizeof(uargs->buf);
2205
2206 inode = file_inode(file);
2207 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2208
2209 /*
2210 * In the origin implementation an overflow is handled by returning a
2211 * search header with a len of zero, so reset ret.
2212 */
2213 if (ret == -EOVERFLOW)
2214 ret = 0;
2215
2216 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2217 ret = -EFAULT;
2218 return ret;
2219 }
2220
2221 static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2222 void __user *argp)
2223 {
2224 struct btrfs_ioctl_search_args_v2 __user *uarg;
2225 struct btrfs_ioctl_search_args_v2 args;
2226 struct inode *inode;
2227 int ret;
2228 size_t buf_size;
2229 const size_t buf_limit = SZ_16M;
2230
2231 if (!capable(CAP_SYS_ADMIN))
2232 return -EPERM;
2233
2234 /* copy search header and buffer size */
2235 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2236 if (copy_from_user(&args, uarg, sizeof(args)))
2237 return -EFAULT;
2238
2239 buf_size = args.buf_size;
2240
2241 /* limit result size to 16MB */
2242 if (buf_size > buf_limit)
2243 buf_size = buf_limit;
2244
2245 inode = file_inode(file);
2246 ret = search_ioctl(inode, &args.key, &buf_size,
2247 (char __user *)(&uarg->buf[0]));
2248 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2249 ret = -EFAULT;
2250 else if (ret == -EOVERFLOW &&
2251 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2252 ret = -EFAULT;
2253
2254 return ret;
2255 }
2256
2257 /*
2258 * Search INODE_REFs to identify path name of 'dirid' directory
2259 * in a 'tree_id' tree. and sets path name to 'name'.
2260 */
2261 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2262 u64 tree_id, u64 dirid, char *name)
2263 {
2264 struct btrfs_root *root;
2265 struct btrfs_key key;
2266 char *ptr;
2267 int ret = -1;
2268 int slot;
2269 int len;
2270 int total_len = 0;
2271 struct btrfs_inode_ref *iref;
2272 struct extent_buffer *l;
2273 struct btrfs_path *path;
2274
2275 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2276 name[0]='\0';
2277 return 0;
2278 }
2279
2280 path = btrfs_alloc_path();
2281 if (!path)
2282 return -ENOMEM;
2283
2284 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1];
2285
2286 key.objectid = tree_id;
2287 key.type = BTRFS_ROOT_ITEM_KEY;
2288 key.offset = (u64)-1;
2289 root = btrfs_read_fs_root_no_name(info, &key);
2290 if (IS_ERR(root)) {
2291 ret = PTR_ERR(root);
2292 goto out;
2293 }
2294
2295 key.objectid = dirid;
2296 key.type = BTRFS_INODE_REF_KEY;
2297 key.offset = (u64)-1;
2298
2299 while (1) {
2300 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2301 if (ret < 0)
2302 goto out;
2303 else if (ret > 0) {
2304 ret = btrfs_previous_item(root, path, dirid,
2305 BTRFS_INODE_REF_KEY);
2306 if (ret < 0)
2307 goto out;
2308 else if (ret > 0) {
2309 ret = -ENOENT;
2310 goto out;
2311 }
2312 }
2313
2314 l = path->nodes[0];
2315 slot = path->slots[0];
2316 btrfs_item_key_to_cpu(l, &key, slot);
2317
2318 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2319 len = btrfs_inode_ref_name_len(l, iref);
2320 ptr -= len + 1;
2321 total_len += len + 1;
2322 if (ptr < name) {
2323 ret = -ENAMETOOLONG;
2324 goto out;
2325 }
2326
2327 *(ptr + len) = '/';
2328 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2329
2330 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2331 break;
2332
2333 btrfs_release_path(path);
2334 key.objectid = key.offset;
2335 key.offset = (u64)-1;
2336 dirid = key.objectid;
2337 }
2338 memmove(name, ptr, total_len);
2339 name[total_len] = '\0';
2340 ret = 0;
2341 out:
2342 btrfs_free_path(path);
2343 return ret;
2344 }
2345
2346 static int btrfs_search_path_in_tree_user(struct inode *inode,
2347 struct btrfs_ioctl_ino_lookup_user_args *args)
2348 {
2349 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2350 struct super_block *sb = inode->i_sb;
2351 struct btrfs_key upper_limit = BTRFS_I(inode)->location;
2352 u64 treeid = BTRFS_I(inode)->root->root_key.objectid;
2353 u64 dirid = args->dirid;
2354 unsigned long item_off;
2355 unsigned long item_len;
2356 struct btrfs_inode_ref *iref;
2357 struct btrfs_root_ref *rref;
2358 struct btrfs_root *root;
2359 struct btrfs_path *path;
2360 struct btrfs_key key, key2;
2361 struct extent_buffer *leaf;
2362 struct inode *temp_inode;
2363 char *ptr;
2364 int slot;
2365 int len;
2366 int total_len = 0;
2367 int ret;
2368
2369 path = btrfs_alloc_path();
2370 if (!path)
2371 return -ENOMEM;
2372
2373 /*
2374 * If the bottom subvolume does not exist directly under upper_limit,
2375 * construct the path in from the bottom up.
2376 */
2377 if (dirid != upper_limit.objectid) {
2378 ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1];
2379
2380 key.objectid = treeid;
2381 key.type = BTRFS_ROOT_ITEM_KEY;
2382 key.offset = (u64)-1;
2383 root = btrfs_read_fs_root_no_name(fs_info, &key);
2384 if (IS_ERR(root)) {
2385 ret = PTR_ERR(root);
2386 goto out;
2387 }
2388
2389 key.objectid = dirid;
2390 key.type = BTRFS_INODE_REF_KEY;
2391 key.offset = (u64)-1;
2392 while (1) {
2393 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2394 if (ret < 0) {
2395 goto out;
2396 } else if (ret > 0) {
2397 ret = btrfs_previous_item(root, path, dirid,
2398 BTRFS_INODE_REF_KEY);
2399 if (ret < 0) {
2400 goto out;
2401 } else if (ret > 0) {
2402 ret = -ENOENT;
2403 goto out;
2404 }
2405 }
2406
2407 leaf = path->nodes[0];
2408 slot = path->slots[0];
2409 btrfs_item_key_to_cpu(leaf, &key, slot);
2410
2411 iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref);
2412 len = btrfs_inode_ref_name_len(leaf, iref);
2413 ptr -= len + 1;
2414 total_len += len + 1;
2415 if (ptr < args->path) {
2416 ret = -ENAMETOOLONG;
2417 goto out;
2418 }
2419
2420 *(ptr + len) = '/';
2421 read_extent_buffer(leaf, ptr,
2422 (unsigned long)(iref + 1), len);
2423
2424 /* Check the read+exec permission of this directory */
2425 ret = btrfs_previous_item(root, path, dirid,
2426 BTRFS_INODE_ITEM_KEY);
2427 if (ret < 0) {
2428 goto out;
2429 } else if (ret > 0) {
2430 ret = -ENOENT;
2431 goto out;
2432 }
2433
2434 leaf = path->nodes[0];
2435 slot = path->slots[0];
2436 btrfs_item_key_to_cpu(leaf, &key2, slot);
2437 if (key2.objectid != dirid) {
2438 ret = -ENOENT;
2439 goto out;
2440 }
2441
2442 temp_inode = btrfs_iget(sb, &key2, root, NULL);
2443 if (IS_ERR(temp_inode)) {
2444 ret = PTR_ERR(temp_inode);
2445 goto out;
2446 }
2447 ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC);
2448 iput(temp_inode);
2449 if (ret) {
2450 ret = -EACCES;
2451 goto out;
2452 }
2453
2454 if (key.offset == upper_limit.objectid)
2455 break;
2456 if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {
2457 ret = -EACCES;
2458 goto out;
2459 }
2460
2461 btrfs_release_path(path);
2462 key.objectid = key.offset;
2463 key.offset = (u64)-1;
2464 dirid = key.objectid;
2465 }
2466
2467 memmove(args->path, ptr, total_len);
2468 args->path[total_len] = '\0';
2469 btrfs_release_path(path);
2470 }
2471
2472 /* Get the bottom subvolume's name from ROOT_REF */
2473 root = fs_info->tree_root;
2474 key.objectid = treeid;
2475 key.type = BTRFS_ROOT_REF_KEY;
2476 key.offset = args->treeid;
2477 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2478 if (ret < 0) {
2479 goto out;
2480 } else if (ret > 0) {
2481 ret = -ENOENT;
2482 goto out;
2483 }
2484
2485 leaf = path->nodes[0];
2486 slot = path->slots[0];
2487 btrfs_item_key_to_cpu(leaf, &key, slot);
2488
2489 item_off = btrfs_item_ptr_offset(leaf, slot);
2490 item_len = btrfs_item_size_nr(leaf, slot);
2491 /* Check if dirid in ROOT_REF corresponds to passed dirid */
2492 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2493 if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) {
2494 ret = -EINVAL;
2495 goto out;
2496 }
2497
2498 /* Copy subvolume's name */
2499 item_off += sizeof(struct btrfs_root_ref);
2500 item_len -= sizeof(struct btrfs_root_ref);
2501 read_extent_buffer(leaf, args->name, item_off, item_len);
2502 args->name[item_len] = 0;
2503
2504 out:
2505 btrfs_free_path(path);
2506 return ret;
2507 }
2508
2509 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2510 void __user *argp)
2511 {
2512 struct btrfs_ioctl_ino_lookup_args *args;
2513 struct inode *inode;
2514 int ret = 0;
2515
2516 args = memdup_user(argp, sizeof(*args));
2517 if (IS_ERR(args))
2518 return PTR_ERR(args);
2519
2520 inode = file_inode(file);
2521
2522 /*
2523 * Unprivileged query to obtain the containing subvolume root id. The
2524 * path is reset so it's consistent with btrfs_search_path_in_tree.
2525 */
2526 if (args->treeid == 0)
2527 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2528
2529 if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2530 args->name[0] = 0;
2531 goto out;
2532 }
2533
2534 if (!capable(CAP_SYS_ADMIN)) {
2535 ret = -EPERM;
2536 goto out;
2537 }
2538
2539 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2540 args->treeid, args->objectid,
2541 args->name);
2542
2543 out:
2544 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2545 ret = -EFAULT;
2546
2547 kfree(args);
2548 return ret;
2549 }
2550
2551 /*
2552 * Version of ino_lookup ioctl (unprivileged)
2553 *
2554 * The main differences from ino_lookup ioctl are:
2555 *
2556 * 1. Read + Exec permission will be checked using inode_permission() during
2557 * path construction. -EACCES will be returned in case of failure.
2558 * 2. Path construction will be stopped at the inode number which corresponds
2559 * to the fd with which this ioctl is called. If constructed path does not
2560 * exist under fd's inode, -EACCES will be returned.
2561 * 3. The name of bottom subvolume is also searched and filled.
2562 */
2563 static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp)
2564 {
2565 struct btrfs_ioctl_ino_lookup_user_args *args;
2566 struct inode *inode;
2567 int ret;
2568
2569 args = memdup_user(argp, sizeof(*args));
2570 if (IS_ERR(args))
2571 return PTR_ERR(args);
2572
2573 inode = file_inode(file);
2574
2575 if (args->dirid == BTRFS_FIRST_FREE_OBJECTID &&
2576 BTRFS_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) {
2577 /*
2578 * The subvolume does not exist under fd with which this is
2579 * called
2580 */
2581 kfree(args);
2582 return -EACCES;
2583 }
2584
2585 ret = btrfs_search_path_in_tree_user(inode, args);
2586
2587 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2588 ret = -EFAULT;
2589
2590 kfree(args);
2591 return ret;
2592 }
2593
2594 /* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */
2595 static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp)
2596 {
2597 struct btrfs_ioctl_get_subvol_info_args *subvol_info;
2598 struct btrfs_fs_info *fs_info;
2599 struct btrfs_root *root;
2600 struct btrfs_path *path;
2601 struct btrfs_key key;
2602 struct btrfs_root_item *root_item;
2603 struct btrfs_root_ref *rref;
2604 struct extent_buffer *leaf;
2605 unsigned long item_off;
2606 unsigned long item_len;
2607 struct inode *inode;
2608 int slot;
2609 int ret = 0;
2610
2611 path = btrfs_alloc_path();
2612 if (!path)
2613 return -ENOMEM;
2614
2615 subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL);
2616 if (!subvol_info) {
2617 btrfs_free_path(path);
2618 return -ENOMEM;
2619 }
2620
2621 inode = file_inode(file);
2622 fs_info = BTRFS_I(inode)->root->fs_info;
2623
2624 /* Get root_item of inode's subvolume */
2625 key.objectid = BTRFS_I(inode)->root->root_key.objectid;
2626 key.type = BTRFS_ROOT_ITEM_KEY;
2627 key.offset = (u64)-1;
2628 root = btrfs_read_fs_root_no_name(fs_info, &key);
2629 if (IS_ERR(root)) {
2630 ret = PTR_ERR(root);
2631 goto out;
2632 }
2633 root_item = &root->root_item;
2634
2635 subvol_info->treeid = key.objectid;
2636
2637 subvol_info->generation = btrfs_root_generation(root_item);
2638 subvol_info->flags = btrfs_root_flags(root_item);
2639
2640 memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE);
2641 memcpy(subvol_info->parent_uuid, root_item->parent_uuid,
2642 BTRFS_UUID_SIZE);
2643 memcpy(subvol_info->received_uuid, root_item->received_uuid,
2644 BTRFS_UUID_SIZE);
2645
2646 subvol_info->ctransid = btrfs_root_ctransid(root_item);
2647 subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime);
2648 subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime);
2649
2650 subvol_info->otransid = btrfs_root_otransid(root_item);
2651 subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime);
2652 subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime);
2653
2654 subvol_info->stransid = btrfs_root_stransid(root_item);
2655 subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime);
2656 subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime);
2657
2658 subvol_info->rtransid = btrfs_root_rtransid(root_item);
2659 subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime);
2660 subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime);
2661
2662 if (key.objectid != BTRFS_FS_TREE_OBJECTID) {
2663 /* Search root tree for ROOT_BACKREF of this subvolume */
2664 root = fs_info->tree_root;
2665
2666 key.type = BTRFS_ROOT_BACKREF_KEY;
2667 key.offset = 0;
2668 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2669 if (ret < 0) {
2670 goto out;
2671 } else if (path->slots[0] >=
2672 btrfs_header_nritems(path->nodes[0])) {
2673 ret = btrfs_next_leaf(root, path);
2674 if (ret < 0) {
2675 goto out;
2676 } else if (ret > 0) {
2677 ret = -EUCLEAN;
2678 goto out;
2679 }
2680 }
2681
2682 leaf = path->nodes[0];
2683 slot = path->slots[0];
2684 btrfs_item_key_to_cpu(leaf, &key, slot);
2685 if (key.objectid == subvol_info->treeid &&
2686 key.type == BTRFS_ROOT_BACKREF_KEY) {
2687 subvol_info->parent_id = key.offset;
2688
2689 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2690 subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref);
2691
2692 item_off = btrfs_item_ptr_offset(leaf, slot)
2693 + sizeof(struct btrfs_root_ref);
2694 item_len = btrfs_item_size_nr(leaf, slot)
2695 - sizeof(struct btrfs_root_ref);
2696 read_extent_buffer(leaf, subvol_info->name,
2697 item_off, item_len);
2698 } else {
2699 ret = -ENOENT;
2700 goto out;
2701 }
2702 }
2703
2704 if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))
2705 ret = -EFAULT;
2706
2707 out:
2708 btrfs_free_path(path);
2709 kzfree(subvol_info);
2710 return ret;
2711 }
2712
2713 /*
2714 * Return ROOT_REF information of the subvolume containing this inode
2715 * except the subvolume name.
2716 */
2717 static int btrfs_ioctl_get_subvol_rootref(struct file *file, void __user *argp)
2718 {
2719 struct btrfs_ioctl_get_subvol_rootref_args *rootrefs;
2720 struct btrfs_root_ref *rref;
2721 struct btrfs_root *root;
2722 struct btrfs_path *path;
2723 struct btrfs_key key;
2724 struct extent_buffer *leaf;
2725 struct inode *inode;
2726 u64 objectid;
2727 int slot;
2728 int ret;
2729 u8 found;
2730
2731 path = btrfs_alloc_path();
2732 if (!path)
2733 return -ENOMEM;
2734
2735 rootrefs = memdup_user(argp, sizeof(*rootrefs));
2736 if (IS_ERR(rootrefs)) {
2737 btrfs_free_path(path);
2738 return PTR_ERR(rootrefs);
2739 }
2740
2741 inode = file_inode(file);
2742 root = BTRFS_I(inode)->root->fs_info->tree_root;
2743 objectid = BTRFS_I(inode)->root->root_key.objectid;
2744
2745 key.objectid = objectid;
2746 key.type = BTRFS_ROOT_REF_KEY;
2747 key.offset = rootrefs->min_treeid;
2748 found = 0;
2749
2750 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2751 if (ret < 0) {
2752 goto out;
2753 } else if (path->slots[0] >=
2754 btrfs_header_nritems(path->nodes[0])) {
2755 ret = btrfs_next_leaf(root, path);
2756 if (ret < 0) {
2757 goto out;
2758 } else if (ret > 0) {
2759 ret = -EUCLEAN;
2760 goto out;
2761 }
2762 }
2763 while (1) {
2764 leaf = path->nodes[0];
2765 slot = path->slots[0];
2766
2767 btrfs_item_key_to_cpu(leaf, &key, slot);
2768 if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) {
2769 ret = 0;
2770 goto out;
2771 }
2772
2773 if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) {
2774 ret = -EOVERFLOW;
2775 goto out;
2776 }
2777
2778 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2779 rootrefs->rootref[found].treeid = key.offset;
2780 rootrefs->rootref[found].dirid =
2781 btrfs_root_ref_dirid(leaf, rref);
2782 found++;
2783
2784 ret = btrfs_next_item(root, path);
2785 if (ret < 0) {
2786 goto out;
2787 } else if (ret > 0) {
2788 ret = -EUCLEAN;
2789 goto out;
2790 }
2791 }
2792
2793 out:
2794 if (!ret || ret == -EOVERFLOW) {
2795 rootrefs->num_items = found;
2796 /* update min_treeid for next search */
2797 if (found)
2798 rootrefs->min_treeid =
2799 rootrefs->rootref[found - 1].treeid + 1;
2800 if (copy_to_user(argp, rootrefs, sizeof(*rootrefs)))
2801 ret = -EFAULT;
2802 }
2803
2804 kfree(rootrefs);
2805 btrfs_free_path(path);
2806
2807 return ret;
2808 }
2809
2810 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2811 void __user *arg)
2812 {
2813 struct dentry *parent = file->f_path.dentry;
2814 struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb);
2815 struct dentry *dentry;
2816 struct inode *dir = d_inode(parent);
2817 struct inode *inode;
2818 struct btrfs_root *root = BTRFS_I(dir)->root;
2819 struct btrfs_root *dest = NULL;
2820 struct btrfs_ioctl_vol_args *vol_args;
2821 int namelen;
2822 int err = 0;
2823
2824 if (!S_ISDIR(dir->i_mode))
2825 return -ENOTDIR;
2826
2827 vol_args = memdup_user(arg, sizeof(*vol_args));
2828 if (IS_ERR(vol_args))
2829 return PTR_ERR(vol_args);
2830
2831 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2832 namelen = strlen(vol_args->name);
2833 if (strchr(vol_args->name, '/') ||
2834 strncmp(vol_args->name, "..", namelen) == 0) {
2835 err = -EINVAL;
2836 goto out;
2837 }
2838
2839 err = mnt_want_write_file(file);
2840 if (err)
2841 goto out;
2842
2843
2844 err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
2845 if (err == -EINTR)
2846 goto out_drop_write;
2847 dentry = lookup_one_len(vol_args->name, parent, namelen);
2848 if (IS_ERR(dentry)) {
2849 err = PTR_ERR(dentry);
2850 goto out_unlock_dir;
2851 }
2852
2853 if (d_really_is_negative(dentry)) {
2854 err = -ENOENT;
2855 goto out_dput;
2856 }
2857
2858 inode = d_inode(dentry);
2859 dest = BTRFS_I(inode)->root;
2860 if (!capable(CAP_SYS_ADMIN)) {
2861 /*
2862 * Regular user. Only allow this with a special mount
2863 * option, when the user has write+exec access to the
2864 * subvol root, and when rmdir(2) would have been
2865 * allowed.
2866 *
2867 * Note that this is _not_ check that the subvol is
2868 * empty or doesn't contain data that we wouldn't
2869 * otherwise be able to delete.
2870 *
2871 * Users who want to delete empty subvols should try
2872 * rmdir(2).
2873 */
2874 err = -EPERM;
2875 if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))
2876 goto out_dput;
2877
2878 /*
2879 * Do not allow deletion if the parent dir is the same
2880 * as the dir to be deleted. That means the ioctl
2881 * must be called on the dentry referencing the root
2882 * of the subvol, not a random directory contained
2883 * within it.
2884 */
2885 err = -EINVAL;
2886 if (root == dest)
2887 goto out_dput;
2888
2889 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2890 if (err)
2891 goto out_dput;
2892 }
2893
2894 /* check if subvolume may be deleted by a user */
2895 err = btrfs_may_delete(dir, dentry, 1);
2896 if (err)
2897 goto out_dput;
2898
2899 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
2900 err = -EINVAL;
2901 goto out_dput;
2902 }
2903
2904 inode_lock(inode);
2905 err = btrfs_delete_subvolume(dir, dentry);
2906 inode_unlock(inode);
2907 if (!err)
2908 d_delete(dentry);
2909
2910 out_dput:
2911 dput(dentry);
2912 out_unlock_dir:
2913 inode_unlock(dir);
2914 out_drop_write:
2915 mnt_drop_write_file(file);
2916 out:
2917 kfree(vol_args);
2918 return err;
2919 }
2920
2921 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2922 {
2923 struct inode *inode = file_inode(file);
2924 struct btrfs_root *root = BTRFS_I(inode)->root;
2925 struct btrfs_ioctl_defrag_range_args *range;
2926 int ret;
2927
2928 ret = mnt_want_write_file(file);
2929 if (ret)
2930 return ret;
2931
2932 if (btrfs_root_readonly(root)) {
2933 ret = -EROFS;
2934 goto out;
2935 }
2936
2937 switch (inode->i_mode & S_IFMT) {
2938 case S_IFDIR:
2939 if (!capable(CAP_SYS_ADMIN)) {
2940 ret = -EPERM;
2941 goto out;
2942 }
2943 ret = btrfs_defrag_root(root);
2944 break;
2945 case S_IFREG:
2946 /*
2947 * Note that this does not check the file descriptor for write
2948 * access. This prevents defragmenting executables that are
2949 * running and allows defrag on files open in read-only mode.
2950 */
2951 if (!capable(CAP_SYS_ADMIN) &&
2952 inode_permission(inode, MAY_WRITE)) {
2953 ret = -EPERM;
2954 goto out;
2955 }
2956
2957 range = kzalloc(sizeof(*range), GFP_KERNEL);
2958 if (!range) {
2959 ret = -ENOMEM;
2960 goto out;
2961 }
2962
2963 if (argp) {
2964 if (copy_from_user(range, argp,
2965 sizeof(*range))) {
2966 ret = -EFAULT;
2967 kfree(range);
2968 goto out;
2969 }
2970 /* compression requires us to start the IO */
2971 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2972 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2973 range->extent_thresh = (u32)-1;
2974 }
2975 } else {
2976 /* the rest are all set to zero by kzalloc */
2977 range->len = (u64)-1;
2978 }
2979 ret = btrfs_defrag_file(file_inode(file), file,
2980 range, BTRFS_OLDEST_GENERATION, 0);
2981 if (ret > 0)
2982 ret = 0;
2983 kfree(range);
2984 break;
2985 default:
2986 ret = -EINVAL;
2987 }
2988 out:
2989 mnt_drop_write_file(file);
2990 return ret;
2991 }
2992
2993 static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg)
2994 {
2995 struct btrfs_ioctl_vol_args *vol_args;
2996 int ret;
2997
2998 if (!capable(CAP_SYS_ADMIN))
2999 return -EPERM;
3000
3001 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags))
3002 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3003
3004 vol_args = memdup_user(arg, sizeof(*vol_args));
3005 if (IS_ERR(vol_args)) {
3006 ret = PTR_ERR(vol_args);
3007 goto out;
3008 }
3009
3010 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3011 ret = btrfs_init_new_device(fs_info, vol_args->name);
3012
3013 if (!ret)
3014 btrfs_info(fs_info, "disk added %s", vol_args->name);
3015
3016 kfree(vol_args);
3017 out:
3018 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3019 return ret;
3020 }
3021
3022 static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
3023 {
3024 struct inode *inode = file_inode(file);
3025 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3026 struct btrfs_ioctl_vol_args_v2 *vol_args;
3027 int ret;
3028
3029 if (!capable(CAP_SYS_ADMIN))
3030 return -EPERM;
3031
3032 ret = mnt_want_write_file(file);
3033 if (ret)
3034 return ret;
3035
3036 vol_args = memdup_user(arg, sizeof(*vol_args));
3037 if (IS_ERR(vol_args)) {
3038 ret = PTR_ERR(vol_args);
3039 goto err_drop;
3040 }
3041
3042 /* Check for compatibility reject unknown flags */
3043 if (vol_args->flags & ~BTRFS_VOL_ARG_V2_FLAGS_SUPPORTED) {
3044 ret = -EOPNOTSUPP;
3045 goto out;
3046 }
3047
3048 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
3049 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3050 goto out;
3051 }
3052
3053 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
3054 ret = btrfs_rm_device(fs_info, NULL, vol_args->devid);
3055 } else {
3056 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
3057 ret = btrfs_rm_device(fs_info, vol_args->name, 0);
3058 }
3059 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3060
3061 if (!ret) {
3062 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
3063 btrfs_info(fs_info, "device deleted: id %llu",
3064 vol_args->devid);
3065 else
3066 btrfs_info(fs_info, "device deleted: %s",
3067 vol_args->name);
3068 }
3069 out:
3070 kfree(vol_args);
3071 err_drop:
3072 mnt_drop_write_file(file);
3073 return ret;
3074 }
3075
3076 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
3077 {
3078 struct inode *inode = file_inode(file);
3079 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3080 struct btrfs_ioctl_vol_args *vol_args;
3081 int ret;
3082
3083 if (!capable(CAP_SYS_ADMIN))
3084 return -EPERM;
3085
3086 ret = mnt_want_write_file(file);
3087 if (ret)
3088 return ret;
3089
3090 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
3091 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3092 goto out_drop_write;
3093 }
3094
3095 vol_args = memdup_user(arg, sizeof(*vol_args));
3096 if (IS_ERR(vol_args)) {
3097 ret = PTR_ERR(vol_args);
3098 goto out;
3099 }
3100
3101 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3102 ret = btrfs_rm_device(fs_info, vol_args->name, 0);
3103
3104 if (!ret)
3105 btrfs_info(fs_info, "disk deleted %s", vol_args->name);
3106 kfree(vol_args);
3107 out:
3108 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3109 out_drop_write:
3110 mnt_drop_write_file(file);
3111
3112 return ret;
3113 }
3114
3115 static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,
3116 void __user *arg)
3117 {
3118 struct btrfs_ioctl_fs_info_args *fi_args;
3119 struct btrfs_device *device;
3120 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
3121 int ret = 0;
3122
3123 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
3124 if (!fi_args)
3125 return -ENOMEM;
3126
3127 rcu_read_lock();
3128 fi_args->num_devices = fs_devices->num_devices;
3129
3130 list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
3131 if (device->devid > fi_args->max_id)
3132 fi_args->max_id = device->devid;
3133 }
3134 rcu_read_unlock();
3135
3136 memcpy(&fi_args->fsid, fs_info->fsid, sizeof(fi_args->fsid));
3137 fi_args->nodesize = fs_info->nodesize;
3138 fi_args->sectorsize = fs_info->sectorsize;
3139 fi_args->clone_alignment = fs_info->sectorsize;
3140
3141 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
3142 ret = -EFAULT;
3143
3144 kfree(fi_args);
3145 return ret;
3146 }
3147
3148 static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,
3149 void __user *arg)
3150 {
3151 struct btrfs_ioctl_dev_info_args *di_args;
3152 struct btrfs_device *dev;
3153 int ret = 0;
3154 char *s_uuid = NULL;
3155
3156 di_args = memdup_user(arg, sizeof(*di_args));
3157 if (IS_ERR(di_args))
3158 return PTR_ERR(di_args);
3159
3160 if (!btrfs_is_empty_uuid(di_args->uuid))
3161 s_uuid = di_args->uuid;
3162
3163 rcu_read_lock();
3164 dev = btrfs_find_device(fs_info, di_args->devid, s_uuid, NULL);
3165
3166 if (!dev) {
3167 ret = -ENODEV;
3168 goto out;
3169 }
3170
3171 di_args->devid = dev->devid;
3172 di_args->bytes_used = btrfs_device_get_bytes_used(dev);
3173 di_args->total_bytes = btrfs_device_get_total_bytes(dev);
3174 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
3175 if (dev->name) {
3176 strncpy(di_args->path, rcu_str_deref(dev->name),
3177 sizeof(di_args->path) - 1);
3178 di_args->path[sizeof(di_args->path) - 1] = 0;
3179 } else {
3180 di_args->path[0] = '\0';
3181 }
3182
3183 out:
3184 rcu_read_unlock();
3185 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
3186 ret = -EFAULT;
3187
3188 kfree(di_args);
3189 return ret;
3190 }
3191
3192 static struct page *extent_same_get_page(struct inode *inode, pgoff_t index)
3193 {
3194 struct page *page;
3195
3196 page = grab_cache_page(inode->i_mapping, index);
3197 if (!page)
3198 return ERR_PTR(-ENOMEM);
3199
3200 if (!PageUptodate(page)) {
3201 int ret;
3202
3203 ret = btrfs_readpage(NULL, page);
3204 if (ret)
3205 return ERR_PTR(ret);
3206 lock_page(page);
3207 if (!PageUptodate(page)) {
3208 unlock_page(page);
3209 put_page(page);
3210 return ERR_PTR(-EIO);
3211 }
3212 if (page->mapping != inode->i_mapping) {
3213 unlock_page(page);
3214 put_page(page);
3215 return ERR_PTR(-EAGAIN);
3216 }
3217 }
3218
3219 return page;
3220 }
3221
3222 static int gather_extent_pages(struct inode *inode, struct page **pages,
3223 int num_pages, u64 off)
3224 {
3225 int i;
3226 pgoff_t index = off >> PAGE_SHIFT;
3227
3228 for (i = 0; i < num_pages; i++) {
3229 again:
3230 pages[i] = extent_same_get_page(inode, index + i);
3231 if (IS_ERR(pages[i])) {
3232 int err = PTR_ERR(pages[i]);
3233
3234 if (err == -EAGAIN)
3235 goto again;
3236 pages[i] = NULL;
3237 return err;
3238 }
3239 }
3240 return 0;
3241 }
3242
3243 static int lock_extent_range(struct inode *inode, u64 off, u64 len,
3244 bool retry_range_locking)
3245 {
3246 /*
3247 * Do any pending delalloc/csum calculations on inode, one way or
3248 * another, and lock file content.
3249 * The locking order is:
3250 *
3251 * 1) pages
3252 * 2) range in the inode's io tree
3253 */
3254 while (1) {
3255 struct btrfs_ordered_extent *ordered;
3256 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
3257 ordered = btrfs_lookup_first_ordered_extent(inode,
3258 off + len - 1);
3259 if ((!ordered ||
3260 ordered->file_offset + ordered->len <= off ||
3261 ordered->file_offset >= off + len) &&
3262 !test_range_bit(&BTRFS_I(inode)->io_tree, off,
3263 off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
3264 if (ordered)
3265 btrfs_put_ordered_extent(ordered);
3266 break;
3267 }
3268 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
3269 if (ordered)
3270 btrfs_put_ordered_extent(ordered);
3271 if (!retry_range_locking)
3272 return -EAGAIN;
3273 btrfs_wait_ordered_range(inode, off, len);
3274 }
3275 return 0;
3276 }
3277
3278 static void btrfs_double_inode_unlock(struct inode *inode1, struct inode *inode2)
3279 {
3280 inode_unlock(inode1);
3281 inode_unlock(inode2);
3282 }
3283
3284 static void btrfs_double_inode_lock(struct inode *inode1, struct inode *inode2)
3285 {
3286 if (inode1 < inode2)
3287 swap(inode1, inode2);
3288
3289 inode_lock_nested(inode1, I_MUTEX_PARENT);
3290 inode_lock_nested(inode2, I_MUTEX_CHILD);
3291 }
3292
3293 static void btrfs_double_extent_unlock(struct inode *inode1, u64 loff1,
3294 struct inode *inode2, u64 loff2, u64 len)
3295 {
3296 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
3297 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
3298 }
3299
3300 static int btrfs_double_extent_lock(struct inode *inode1, u64 loff1,
3301 struct inode *inode2, u64 loff2, u64 len,
3302 bool retry_range_locking)
3303 {
3304 int ret;
3305
3306 if (inode1 < inode2) {
3307 swap(inode1, inode2);
3308 swap(loff1, loff2);
3309 }
3310 ret = lock_extent_range(inode1, loff1, len, retry_range_locking);
3311 if (ret)
3312 return ret;
3313 ret = lock_extent_range(inode2, loff2, len, retry_range_locking);
3314 if (ret)
3315 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1,
3316 loff1 + len - 1);
3317 return ret;
3318 }
3319
3320 struct cmp_pages {
3321 int num_pages;
3322 struct page **src_pages;
3323 struct page **dst_pages;
3324 };
3325
3326 static void btrfs_cmp_data_free(struct cmp_pages *cmp)
3327 {
3328 int i;
3329 struct page *pg;
3330
3331 for (i = 0; i < cmp->num_pages; i++) {
3332 pg = cmp->src_pages[i];
3333 if (pg) {
3334 unlock_page(pg);
3335 put_page(pg);
3336 cmp->src_pages[i] = NULL;
3337 }
3338 pg = cmp->dst_pages[i];
3339 if (pg) {
3340 unlock_page(pg);
3341 put_page(pg);
3342 cmp->dst_pages[i] = NULL;
3343 }
3344 }
3345 }
3346
3347 static int btrfs_cmp_data_prepare(struct inode *src, u64 loff,
3348 struct inode *dst, u64 dst_loff,
3349 u64 len, struct cmp_pages *cmp)
3350 {
3351 int ret;
3352 int num_pages = PAGE_ALIGN(len) >> PAGE_SHIFT;
3353
3354 cmp->num_pages = num_pages;
3355
3356 ret = gather_extent_pages(src, cmp->src_pages, num_pages, loff);
3357 if (ret)
3358 goto out;
3359
3360 ret = gather_extent_pages(dst, cmp->dst_pages, num_pages, dst_loff);
3361
3362 out:
3363 if (ret)
3364 btrfs_cmp_data_free(cmp);
3365 return ret;
3366 }
3367
3368 static int btrfs_cmp_data(u64 len, struct cmp_pages *cmp)
3369 {
3370 int ret = 0;
3371 int i;
3372 struct page *src_page, *dst_page;
3373 unsigned int cmp_len = PAGE_SIZE;
3374 void *addr, *dst_addr;
3375
3376 i = 0;
3377 while (len) {
3378 if (len < PAGE_SIZE)
3379 cmp_len = len;
3380
3381 BUG_ON(i >= cmp->num_pages);
3382
3383 src_page = cmp->src_pages[i];
3384 dst_page = cmp->dst_pages[i];
3385 ASSERT(PageLocked(src_page));
3386 ASSERT(PageLocked(dst_page));
3387
3388 addr = kmap_atomic(src_page);
3389 dst_addr = kmap_atomic(dst_page);
3390
3391 flush_dcache_page(src_page);
3392 flush_dcache_page(dst_page);
3393
3394 if (memcmp(addr, dst_addr, cmp_len))
3395 ret = -EBADE;
3396
3397 kunmap_atomic(addr);
3398 kunmap_atomic(dst_addr);
3399
3400 if (ret)
3401 break;
3402
3403 len -= cmp_len;
3404 i++;
3405 }
3406
3407 return ret;
3408 }
3409
3410 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 *plen,
3411 u64 olen)
3412 {
3413 u64 len = *plen;
3414 u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
3415
3416 if (off + olen > inode->i_size || off + olen < off)
3417 return -EINVAL;
3418
3419 /* if we extend to eof, continue to block boundary */
3420 if (off + len == inode->i_size)
3421 *plen = len = ALIGN(inode->i_size, bs) - off;
3422
3423 /* Check that we are block aligned - btrfs_clone() requires this */
3424 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
3425 return -EINVAL;
3426
3427 return 0;
3428 }
3429
3430 static int btrfs_extent_same_range(struct inode *src, u64 loff, u64 olen,
3431 struct inode *dst, u64 dst_loff,
3432 struct cmp_pages *cmp)
3433 {
3434 int ret;
3435 u64 len = olen;
3436 bool same_inode = (src == dst);
3437 u64 same_lock_start = 0;
3438 u64 same_lock_len = 0;
3439
3440 ret = extent_same_check_offsets(src, loff, &len, olen);
3441 if (ret)
3442 return ret;
3443
3444 ret = extent_same_check_offsets(dst, dst_loff, &len, olen);
3445 if (ret)
3446 return ret;
3447
3448 if (same_inode) {
3449 /*
3450 * Single inode case wants the same checks, except we
3451 * don't want our length pushed out past i_size as
3452 * comparing that data range makes no sense.
3453 *
3454 * extent_same_check_offsets() will do this for an
3455 * unaligned length at i_size, so catch it here and
3456 * reject the request.
3457 *
3458 * This effectively means we require aligned extents
3459 * for the single-inode case, whereas the other cases
3460 * allow an unaligned length so long as it ends at
3461 * i_size.
3462 */
3463 if (len != olen)
3464 return -EINVAL;
3465
3466 /* Check for overlapping ranges */
3467 if (dst_loff + len > loff && dst_loff < loff + len)
3468 return -EINVAL;
3469
3470 same_lock_start = min_t(u64, loff, dst_loff);
3471 same_lock_len = max_t(u64, loff, dst_loff) + len - same_lock_start;
3472 } else {
3473 /*
3474 * If the source and destination inodes are different, the
3475 * source's range end offset matches the source's i_size, that
3476 * i_size is not a multiple of the sector size, and the
3477 * destination range does not go past the destination's i_size,
3478 * we must round down the length to the nearest sector size
3479 * multiple. If we don't do this adjustment we end replacing
3480 * with zeroes the bytes in the range that starts at the
3481 * deduplication range's end offset and ends at the next sector
3482 * size multiple.
3483 */
3484 if (loff + olen == i_size_read(src) &&
3485 dst_loff + len < i_size_read(dst)) {
3486 const u64 sz = BTRFS_I(src)->root->fs_info->sectorsize;
3487
3488 len = round_down(i_size_read(src), sz) - loff;
3489 olen = len;
3490 }
3491 }
3492
3493 again:
3494 ret = btrfs_cmp_data_prepare(src, loff, dst, dst_loff, olen, cmp);
3495 if (ret)
3496 return ret;
3497
3498 if (same_inode)
3499 ret = lock_extent_range(src, same_lock_start, same_lock_len,
3500 false);
3501 else
3502 ret = btrfs_double_extent_lock(src, loff, dst, dst_loff, len,
3503 false);
3504 /*
3505 * If one of the inodes has dirty pages in the respective range or
3506 * ordered extents, we need to flush dellaloc and wait for all ordered
3507 * extents in the range. We must unlock the pages and the ranges in the
3508 * io trees to avoid deadlocks when flushing delalloc (requires locking
3509 * pages) and when waiting for ordered extents to complete (they require
3510 * range locking).
3511 */
3512 if (ret == -EAGAIN) {
3513 /*
3514 * Ranges in the io trees already unlocked. Now unlock all
3515 * pages before waiting for all IO to complete.
3516 */
3517 btrfs_cmp_data_free(cmp);
3518 if (same_inode) {
3519 btrfs_wait_ordered_range(src, same_lock_start,
3520 same_lock_len);
3521 } else {
3522 btrfs_wait_ordered_range(src, loff, len);
3523 btrfs_wait_ordered_range(dst, dst_loff, len);
3524 }
3525 goto again;
3526 }
3527 ASSERT(ret == 0);
3528 if (WARN_ON(ret)) {
3529 /* ranges in the io trees already unlocked */
3530 btrfs_cmp_data_free(cmp);
3531 return ret;
3532 }
3533
3534 /* pass original length for comparison so we stay within i_size */
3535 ret = btrfs_cmp_data(olen, cmp);
3536 if (ret == 0)
3537 ret = btrfs_clone(src, dst, loff, olen, len, dst_loff, 1);
3538
3539 if (same_inode)
3540 unlock_extent(&BTRFS_I(src)->io_tree, same_lock_start,
3541 same_lock_start + same_lock_len - 1);
3542 else
3543 btrfs_double_extent_unlock(src, loff, dst, dst_loff, len);
3544
3545 btrfs_cmp_data_free(cmp);
3546
3547 return ret;
3548 }
3549
3550 #define BTRFS_MAX_DEDUPE_LEN SZ_16M
3551
3552 static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
3553 struct inode *dst, u64 dst_loff)
3554 {
3555 int ret;
3556 struct cmp_pages cmp;
3557 int num_pages = PAGE_ALIGN(BTRFS_MAX_DEDUPE_LEN) >> PAGE_SHIFT;
3558 bool same_inode = (src == dst);
3559 u64 i, tail_len, chunk_count;
3560
3561 if (olen == 0)
3562 return 0;
3563
3564 if (same_inode)
3565 inode_lock(src);
3566 else
3567 btrfs_double_inode_lock(src, dst);
3568
3569 /* don't make the dst file partly checksummed */
3570 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3571 (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
3572 ret = -EINVAL;
3573 goto out_unlock;
3574 }
3575
3576 tail_len = olen % BTRFS_MAX_DEDUPE_LEN;
3577 chunk_count = div_u64(olen, BTRFS_MAX_DEDUPE_LEN);
3578 if (chunk_count == 0)
3579 num_pages = PAGE_ALIGN(tail_len) >> PAGE_SHIFT;
3580
3581 /*
3582 * If deduping ranges in the same inode, locking rules make it
3583 * mandatory to always lock pages in ascending order to avoid deadlocks
3584 * with concurrent tasks (such as starting writeback/delalloc).
3585 */
3586 if (same_inode && dst_loff < loff)
3587 swap(loff, dst_loff);
3588
3589 /*
3590 * We must gather up all the pages before we initiate our extent
3591 * locking. We use an array for the page pointers. Size of the array is
3592 * bounded by len, which is in turn bounded by BTRFS_MAX_DEDUPE_LEN.
3593 */
3594 cmp.src_pages = kvmalloc_array(num_pages, sizeof(struct page *),
3595 GFP_KERNEL | __GFP_ZERO);
3596 cmp.dst_pages = kvmalloc_array(num_pages, sizeof(struct page *),
3597 GFP_KERNEL | __GFP_ZERO);
3598 if (!cmp.src_pages || !cmp.dst_pages) {
3599 ret = -ENOMEM;
3600 goto out_free;
3601 }
3602
3603 for (i = 0; i < chunk_count; i++) {
3604 ret = btrfs_extent_same_range(src, loff, BTRFS_MAX_DEDUPE_LEN,
3605 dst, dst_loff, &cmp);
3606 if (ret)
3607 goto out_free;
3608
3609 loff += BTRFS_MAX_DEDUPE_LEN;
3610 dst_loff += BTRFS_MAX_DEDUPE_LEN;
3611 }
3612
3613 if (tail_len > 0)
3614 ret = btrfs_extent_same_range(src, loff, tail_len, dst,
3615 dst_loff, &cmp);
3616
3617 out_free:
3618 kvfree(cmp.src_pages);
3619 kvfree(cmp.dst_pages);
3620
3621 out_unlock:
3622 if (same_inode)
3623 inode_unlock(src);
3624 else
3625 btrfs_double_inode_unlock(src, dst);
3626
3627 return ret;
3628 }
3629
3630 ssize_t btrfs_dedupe_file_range(struct file *src_file, u64 loff, u64 olen,
3631 struct file *dst_file, u64 dst_loff)
3632 {
3633 struct inode *src = file_inode(src_file);
3634 struct inode *dst = file_inode(dst_file);
3635 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
3636 ssize_t res;
3637
3638 if (WARN_ON_ONCE(bs < PAGE_SIZE)) {
3639 /*
3640 * Btrfs does not support blocksize < page_size. As a
3641 * result, btrfs_cmp_data() won't correctly handle
3642 * this situation without an update.
3643 */
3644 return -EINVAL;
3645 }
3646
3647 res = btrfs_extent_same(src, loff, olen, dst, dst_loff);
3648 if (res)
3649 return res;
3650 return olen;
3651 }
3652
3653 static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3654 struct inode *inode,
3655 u64 endoff,
3656 const u64 destoff,
3657 const u64 olen,
3658 int no_time_update)
3659 {
3660 struct btrfs_root *root = BTRFS_I(inode)->root;
3661 int ret;
3662
3663 inode_inc_iversion(inode);
3664 if (!no_time_update)
3665 inode->i_mtime = inode->i_ctime = current_time(inode);
3666 /*
3667 * We round up to the block size at eof when determining which
3668 * extents to clone above, but shouldn't round up the file size.
3669 */
3670 if (endoff > destoff + olen)
3671 endoff = destoff + olen;
3672 if (endoff > inode->i_size)
3673 btrfs_i_size_write(BTRFS_I(inode), endoff);
3674
3675 ret = btrfs_update_inode(trans, root, inode);
3676 if (ret) {
3677 btrfs_abort_transaction(trans, ret);
3678 btrfs_end_transaction(trans);
3679 goto out;
3680 }
3681 ret = btrfs_end_transaction(trans);
3682 out:
3683 return ret;
3684 }
3685
3686 static void clone_update_extent_map(struct btrfs_inode *inode,
3687 const struct btrfs_trans_handle *trans,
3688 const struct btrfs_path *path,
3689 const u64 hole_offset,
3690 const u64 hole_len)
3691 {
3692 struct extent_map_tree *em_tree = &inode->extent_tree;
3693 struct extent_map *em;
3694 int ret;
3695
3696 em = alloc_extent_map();
3697 if (!em) {
3698 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags);
3699 return;
3700 }
3701
3702 if (path) {
3703 struct btrfs_file_extent_item *fi;
3704
3705 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
3706 struct btrfs_file_extent_item);
3707 btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
3708 em->generation = -1;
3709 if (btrfs_file_extent_type(path->nodes[0], fi) ==
3710 BTRFS_FILE_EXTENT_INLINE)
3711 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3712 &inode->runtime_flags);
3713 } else {
3714 em->start = hole_offset;
3715 em->len = hole_len;
3716 em->ram_bytes = em->len;
3717 em->orig_start = hole_offset;
3718 em->block_start = EXTENT_MAP_HOLE;
3719 em->block_len = 0;
3720 em->orig_block_len = 0;
3721 em->compress_type = BTRFS_COMPRESS_NONE;
3722 em->generation = trans->transid;
3723 }
3724
3725 while (1) {
3726 write_lock(&em_tree->lock);
3727 ret = add_extent_mapping(em_tree, em, 1);
3728 write_unlock(&em_tree->lock);
3729 if (ret != -EEXIST) {
3730 free_extent_map(em);
3731 break;
3732 }
3733 btrfs_drop_extent_cache(inode, em->start,
3734 em->start + em->len - 1, 0);
3735 }
3736
3737 if (ret)
3738 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags);
3739 }
3740
3741 /*
3742 * Make sure we do not end up inserting an inline extent into a file that has
3743 * already other (non-inline) extents. If a file has an inline extent it can
3744 * not have any other extents and the (single) inline extent must start at the
3745 * file offset 0. Failing to respect these rules will lead to file corruption,
3746 * resulting in EIO errors on read/write operations, hitting BUG_ON's in mm, etc
3747 *
3748 * We can have extents that have been already written to disk or we can have
3749 * dirty ranges still in delalloc, in which case the extent maps and items are
3750 * created only when we run delalloc, and the delalloc ranges might fall outside
3751 * the range we are currently locking in the inode's io tree. So we check the
3752 * inode's i_size because of that (i_size updates are done while holding the
3753 * i_mutex, which we are holding here).
3754 * We also check to see if the inode has a size not greater than "datal" but has
3755 * extents beyond it, due to an fallocate with FALLOC_FL_KEEP_SIZE (and we are
3756 * protected against such concurrent fallocate calls by the i_mutex).
3757 *
3758 * If the file has no extents but a size greater than datal, do not allow the
3759 * copy because we would need turn the inline extent into a non-inline one (even
3760 * with NO_HOLES enabled). If we find our destination inode only has one inline
3761 * extent, just overwrite it with the source inline extent if its size is less
3762 * than the source extent's size, or we could copy the source inline extent's
3763 * data into the destination inode's inline extent if the later is greater then
3764 * the former.
3765 */
3766 static int clone_copy_inline_extent(struct inode *dst,
3767 struct btrfs_trans_handle *trans,
3768 struct btrfs_path *path,
3769 struct btrfs_key *new_key,
3770 const u64 drop_start,
3771 const u64 datal,
3772 const u64 skip,
3773 const u64 size,
3774 char *inline_data)
3775 {
3776 struct btrfs_fs_info *fs_info = btrfs_sb(dst->i_sb);
3777 struct btrfs_root *root = BTRFS_I(dst)->root;
3778 const u64 aligned_end = ALIGN(new_key->offset + datal,
3779 fs_info->sectorsize);
3780 int ret;
3781 struct btrfs_key key;
3782
3783 if (new_key->offset > 0)
3784 return -EOPNOTSUPP;
3785
3786 key.objectid = btrfs_ino(BTRFS_I(dst));
3787 key.type = BTRFS_EXTENT_DATA_KEY;
3788 key.offset = 0;
3789 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3790 if (ret < 0) {
3791 return ret;
3792 } else if (ret > 0) {
3793 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
3794 ret = btrfs_next_leaf(root, path);
3795 if (ret < 0)
3796 return ret;
3797 else if (ret > 0)
3798 goto copy_inline_extent;
3799 }
3800 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
3801 if (key.objectid == btrfs_ino(BTRFS_I(dst)) &&
3802 key.type == BTRFS_EXTENT_DATA_KEY) {
3803 ASSERT(key.offset > 0);
3804 return -EOPNOTSUPP;
3805 }
3806 } else if (i_size_read(dst) <= datal) {
3807 struct btrfs_file_extent_item *ei;
3808 u64 ext_len;
3809
3810 /*
3811 * If the file size is <= datal, make sure there are no other
3812 * extents following (can happen do to an fallocate call with
3813 * the flag FALLOC_FL_KEEP_SIZE).
3814 */
3815 ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
3816 struct btrfs_file_extent_item);
3817 /*
3818 * If it's an inline extent, it can not have other extents
3819 * following it.
3820 */
3821 if (btrfs_file_extent_type(path->nodes[0], ei) ==
3822 BTRFS_FILE_EXTENT_INLINE)
3823 goto copy_inline_extent;
3824
3825 ext_len = btrfs_file_extent_num_bytes(path->nodes[0], ei);
3826 if (ext_len > aligned_end)
3827 return -EOPNOTSUPP;
3828
3829 ret = btrfs_next_item(root, path);
3830 if (ret < 0) {
3831 return ret;
3832 } else if (ret == 0) {
3833 btrfs_item_key_to_cpu(path->nodes[0], &key,
3834 path->slots[0]);
3835 if (key.objectid == btrfs_ino(BTRFS_I(dst)) &&
3836 key.type == BTRFS_EXTENT_DATA_KEY)
3837 return -EOPNOTSUPP;
3838 }
3839 }
3840
3841 copy_inline_extent:
3842 /*
3843 * We have no extent items, or we have an extent at offset 0 which may
3844 * or may not be inlined. All these cases are dealt the same way.
3845 */
3846 if (i_size_read(dst) > datal) {
3847 /*
3848 * If the destination inode has an inline extent...
3849 * This would require copying the data from the source inline
3850 * extent into the beginning of the destination's inline extent.
3851 * But this is really complex, both extents can be compressed
3852 * or just one of them, which would require decompressing and
3853 * re-compressing data (which could increase the new compressed
3854 * size, not allowing the compressed data to fit anymore in an
3855 * inline extent).
3856 * So just don't support this case for now (it should be rare,
3857 * we are not really saving space when cloning inline extents).
3858 */
3859 return -EOPNOTSUPP;
3860 }
3861
3862 btrfs_release_path(path);
3863 ret = btrfs_drop_extents(trans, root, dst, drop_start, aligned_end, 1);
3864 if (ret)
3865 return ret;
3866 ret = btrfs_insert_empty_item(trans, root, path, new_key, size);
3867 if (ret)
3868 return ret;
3869
3870 if (skip) {
3871 const u32 start = btrfs_file_extent_calc_inline_size(0);
3872
3873 memmove(inline_data + start, inline_data + start + skip, datal);
3874 }
3875
3876 write_extent_buffer(path->nodes[0], inline_data,
3877 btrfs_item_ptr_offset(path->nodes[0],
3878 path->slots[0]),
3879 size);
3880 inode_add_bytes(dst, datal);
3881
3882 return 0;
3883 }
3884
3885 /**
3886 * btrfs_clone() - clone a range from inode file to another
3887 *
3888 * @src: Inode to clone from
3889 * @inode: Inode to clone to
3890 * @off: Offset within source to start clone from
3891 * @olen: Original length, passed by user, of range to clone
3892 * @olen_aligned: Block-aligned value of olen
3893 * @destoff: Offset within @inode to start clone
3894 * @no_time_update: Whether to update mtime/ctime on the target inode
3895 */
3896 static int btrfs_clone(struct inode *src, struct inode *inode,
3897 const u64 off, const u64 olen, const u64 olen_aligned,
3898 const u64 destoff, int no_time_update)
3899 {
3900 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3901 struct btrfs_root *root = BTRFS_I(inode)->root;
3902 struct btrfs_path *path = NULL;
3903 struct extent_buffer *leaf;
3904 struct btrfs_trans_handle *trans;
3905 char *buf = NULL;
3906 struct btrfs_key key;
3907 u32 nritems;
3908 int slot;
3909 int ret;
3910 const u64 len = olen_aligned;
3911 u64 last_dest_end = destoff;
3912
3913 ret = -ENOMEM;
3914 buf = kvmalloc(fs_info->nodesize, GFP_KERNEL);
3915 if (!buf)
3916 return ret;
3917
3918 path = btrfs_alloc_path();
3919 if (!path) {
3920 kvfree(buf);
3921 return ret;
3922 }
3923
3924 path->reada = READA_FORWARD;
3925 /* clone data */
3926 key.objectid = btrfs_ino(BTRFS_I(src));
3927 key.type = BTRFS_EXTENT_DATA_KEY;
3928 key.offset = off;
3929
3930 while (1) {
3931 u64 next_key_min_offset = key.offset + 1;
3932
3933 /*
3934 * note the key will change type as we walk through the
3935 * tree.
3936 */
3937 path->leave_spinning = 1;
3938 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3939 0, 0);
3940 if (ret < 0)
3941 goto out;
3942 /*
3943 * First search, if no extent item that starts at offset off was
3944 * found but the previous item is an extent item, it's possible
3945 * it might overlap our target range, therefore process it.
3946 */
3947 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3948 btrfs_item_key_to_cpu(path->nodes[0], &key,
3949 path->slots[0] - 1);
3950 if (key.type == BTRFS_EXTENT_DATA_KEY)
3951 path->slots[0]--;
3952 }
3953
3954 nritems = btrfs_header_nritems(path->nodes[0]);
3955 process_slot:
3956 if (path->slots[0] >= nritems) {
3957 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3958 if (ret < 0)
3959 goto out;
3960 if (ret > 0)
3961 break;
3962 nritems = btrfs_header_nritems(path->nodes[0]);
3963 }
3964 leaf = path->nodes[0];
3965 slot = path->slots[0];
3966
3967 btrfs_item_key_to_cpu(leaf, &key, slot);
3968 if (key.type > BTRFS_EXTENT_DATA_KEY ||
3969 key.objectid != btrfs_ino(BTRFS_I(src)))
3970 break;
3971
3972 if (key.type == BTRFS_EXTENT_DATA_KEY) {
3973 struct btrfs_file_extent_item *extent;
3974 int type;
3975 u32 size;
3976 struct btrfs_key new_key;
3977 u64 disko = 0, diskl = 0;
3978 u64 datao = 0, datal = 0;
3979 u8 comp;
3980 u64 drop_start;
3981
3982 extent = btrfs_item_ptr(leaf, slot,
3983 struct btrfs_file_extent_item);
3984 comp = btrfs_file_extent_compression(leaf, extent);
3985 type = btrfs_file_extent_type(leaf, extent);
3986 if (type == BTRFS_FILE_EXTENT_REG ||
3987 type == BTRFS_FILE_EXTENT_PREALLOC) {
3988 disko = btrfs_file_extent_disk_bytenr(leaf,
3989 extent);
3990 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3991 extent);
3992 datao = btrfs_file_extent_offset(leaf, extent);
3993 datal = btrfs_file_extent_num_bytes(leaf,
3994 extent);
3995 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3996 /* take upper bound, may be compressed */
3997 datal = btrfs_file_extent_ram_bytes(leaf,
3998 extent);
3999 }
4000
4001 /*
4002 * The first search might have left us at an extent
4003 * item that ends before our target range's start, can
4004 * happen if we have holes and NO_HOLES feature enabled.
4005 */
4006 if (key.offset + datal <= off) {
4007 path->slots[0]++;
4008 goto process_slot;
4009 } else if (key.offset >= off + len) {
4010 break;
4011 }
4012 next_key_min_offset = key.offset + datal;
4013 size = btrfs_item_size_nr(leaf, slot);
4014 read_extent_buffer(leaf, buf,
4015 btrfs_item_ptr_offset(leaf, slot),
4016 size);
4017
4018 btrfs_release_path(path);
4019 path->leave_spinning = 0;
4020
4021 memcpy(&new_key, &key, sizeof(new_key));
4022 new_key.objectid = btrfs_ino(BTRFS_I(inode));
4023 if (off <= key.offset)
4024 new_key.offset = key.offset + destoff - off;
4025 else
4026 new_key.offset = destoff;
4027
4028 /*
4029 * Deal with a hole that doesn't have an extent item
4030 * that represents it (NO_HOLES feature enabled).
4031 * This hole is either in the middle of the cloning
4032 * range or at the beginning (fully overlaps it or
4033 * partially overlaps it).
4034 */
4035 if (new_key.offset != last_dest_end)
4036 drop_start = last_dest_end;
4037 else
4038 drop_start = new_key.offset;
4039
4040 /*
4041 * 1 - adjusting old extent (we may have to split it)
4042 * 1 - add new extent
4043 * 1 - inode update
4044 */
4045 trans = btrfs_start_transaction(root, 3);
4046 if (IS_ERR(trans)) {
4047 ret = PTR_ERR(trans);
4048 goto out;
4049 }
4050
4051 if (type == BTRFS_FILE_EXTENT_REG ||
4052 type == BTRFS_FILE_EXTENT_PREALLOC) {
4053 /*
4054 * a | --- range to clone ---| b
4055 * | ------------- extent ------------- |
4056 */
4057
4058 /* subtract range b */
4059 if (key.offset + datal > off + len)
4060 datal = off + len - key.offset;
4061
4062 /* subtract range a */
4063 if (off > key.offset) {
4064 datao += off - key.offset;
4065 datal -= off - key.offset;
4066 }
4067
4068 ret = btrfs_drop_extents(trans, root, inode,
4069 drop_start,
4070 new_key.offset + datal,
4071 1);
4072 if (ret) {
4073 if (ret != -EOPNOTSUPP)
4074 btrfs_abort_transaction(trans,
4075 ret);
4076 btrfs_end_transaction(trans);
4077 goto out;
4078 }
4079
4080 ret = btrfs_insert_empty_item(trans, root, path,
4081 &new_key, size);
4082 if (ret) {
4083 btrfs_abort_transaction(trans, ret);
4084 btrfs_end_transaction(trans);
4085 goto out;
4086 }
4087
4088 leaf = path->nodes[0];
4089 slot = path->slots[0];
4090 write_extent_buffer(leaf, buf,
4091 btrfs_item_ptr_offset(leaf, slot),
4092 size);
4093
4094 extent = btrfs_item_ptr(leaf, slot,
4095 struct btrfs_file_extent_item);
4096
4097 /* disko == 0 means it's a hole */
4098 if (!disko)
4099 datao = 0;
4100
4101 btrfs_set_file_extent_offset(leaf, extent,
4102 datao);
4103 btrfs_set_file_extent_num_bytes(leaf, extent,
4104 datal);
4105
4106 if (disko) {
4107 inode_add_bytes(inode, datal);
4108 ret = btrfs_inc_extent_ref(trans,
4109 root,
4110 disko, diskl, 0,
4111 root->root_key.objectid,
4112 btrfs_ino(BTRFS_I(inode)),
4113 new_key.offset - datao);
4114 if (ret) {
4115 btrfs_abort_transaction(trans,
4116 ret);
4117 btrfs_end_transaction(trans);
4118 goto out;
4119
4120 }
4121 }
4122 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
4123 u64 skip = 0;
4124 u64 trim = 0;
4125
4126 if (off > key.offset) {
4127 skip = off - key.offset;
4128 new_key.offset += skip;
4129 }
4130
4131 if (key.offset + datal > off + len)
4132 trim = key.offset + datal - (off + len);
4133
4134 if (comp && (skip || trim)) {
4135 ret = -EINVAL;
4136 btrfs_end_transaction(trans);
4137 goto out;
4138 }
4139 size -= skip + trim;
4140 datal -= skip + trim;
4141
4142 ret = clone_copy_inline_extent(inode,
4143 trans, path,
4144 &new_key,
4145 drop_start,
4146 datal,
4147 skip, size, buf);
4148 if (ret) {
4149 if (ret != -EOPNOTSUPP)
4150 btrfs_abort_transaction(trans,
4151 ret);
4152 btrfs_end_transaction(trans);
4153 goto out;
4154 }
4155 leaf = path->nodes[0];
4156 slot = path->slots[0];
4157 }
4158
4159 /* If we have an implicit hole (NO_HOLES feature). */
4160 if (drop_start < new_key.offset)
4161 clone_update_extent_map(BTRFS_I(inode), trans,
4162 NULL, drop_start,
4163 new_key.offset - drop_start);
4164
4165 clone_update_extent_map(BTRFS_I(inode), trans,
4166 path, 0, 0);
4167
4168 btrfs_mark_buffer_dirty(leaf);
4169 btrfs_release_path(path);
4170
4171 last_dest_end = ALIGN(new_key.offset + datal,
4172 fs_info->sectorsize);
4173 ret = clone_finish_inode_update(trans, inode,
4174 last_dest_end,
4175 destoff, olen,
4176 no_time_update);
4177 if (ret)
4178 goto out;
4179 if (new_key.offset + datal >= destoff + len)
4180 break;
4181 }
4182 btrfs_release_path(path);
4183 key.offset = next_key_min_offset;
4184
4185 if (fatal_signal_pending(current)) {
4186 ret = -EINTR;
4187 goto out;
4188 }
4189 }
4190 ret = 0;
4191
4192 if (last_dest_end < destoff + len) {
4193 /*
4194 * We have an implicit hole (NO_HOLES feature is enabled) that
4195 * fully or partially overlaps our cloning range at its end.
4196 */
4197 btrfs_release_path(path);
4198
4199 /*
4200 * 1 - remove extent(s)
4201 * 1 - inode update
4202 */
4203 trans = btrfs_start_transaction(root, 2);
4204 if (IS_ERR(trans)) {
4205 ret = PTR_ERR(trans);
4206 goto out;
4207 }
4208 ret = btrfs_drop_extents(trans, root, inode,
4209 last_dest_end, destoff + len, 1);
4210 if (ret) {
4211 if (ret != -EOPNOTSUPP)
4212 btrfs_abort_transaction(trans, ret);
4213 btrfs_end_transaction(trans);
4214 goto out;
4215 }
4216 clone_update_extent_map(BTRFS_I(inode), trans, NULL,
4217 last_dest_end,
4218 destoff + len - last_dest_end);
4219 ret = clone_finish_inode_update(trans, inode, destoff + len,
4220 destoff, olen, no_time_update);
4221 }
4222
4223 out:
4224 btrfs_free_path(path);
4225 kvfree(buf);
4226 return ret;
4227 }
4228
4229 static noinline int btrfs_clone_files(struct file *file, struct file *file_src,
4230 u64 off, u64 olen, u64 destoff)
4231 {
4232 struct inode *inode = file_inode(file);
4233 struct inode *src = file_inode(file_src);
4234 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4235 struct btrfs_root *root = BTRFS_I(inode)->root;
4236 int ret;
4237 u64 len = olen;
4238 u64 bs = fs_info->sb->s_blocksize;
4239 int same_inode = src == inode;
4240
4241 /*
4242 * TODO:
4243 * - split compressed inline extents. annoying: we need to
4244 * decompress into destination's address_space (the file offset
4245 * may change, so source mapping won't do), then recompress (or
4246 * otherwise reinsert) a subrange.
4247 *
4248 * - split destination inode's inline extents. The inline extents can
4249 * be either compressed or non-compressed.
4250 */
4251
4252 if (btrfs_root_readonly(root))
4253 return -EROFS;
4254
4255 if (file_src->f_path.mnt != file->f_path.mnt ||
4256 src->i_sb != inode->i_sb)
4257 return -EXDEV;
4258
4259 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
4260 return -EISDIR;
4261
4262 if (!same_inode) {
4263 btrfs_double_inode_lock(src, inode);
4264 } else {
4265 inode_lock(src);
4266 }
4267
4268 /* don't make the dst file partly checksummed */
4269 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
4270 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
4271 ret = -EINVAL;
4272 goto out_unlock;
4273 }
4274
4275 /* determine range to clone */
4276 ret = -EINVAL;
4277 if (off + len > src->i_size || off + len < off)
4278 goto out_unlock;
4279 if (len == 0)
4280 olen = len = src->i_size - off;
4281 /* if we extend to eof, continue to block boundary */
4282 if (off + len == src->i_size)
4283 len = ALIGN(src->i_size, bs) - off;
4284
4285 if (len == 0) {
4286 ret = 0;
4287 goto out_unlock;
4288 }
4289
4290 /* verify the end result is block aligned */
4291 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
4292 !IS_ALIGNED(destoff, bs))
4293 goto out_unlock;
4294
4295 /* verify if ranges are overlapped within the same file */
4296 if (same_inode) {
4297 if (destoff + len > off && destoff < off + len)
4298 goto out_unlock;
4299 }
4300
4301 if (destoff > inode->i_size) {
4302 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
4303 if (ret)
4304 goto out_unlock;
4305 }
4306
4307 /*
4308 * Lock the target range too. Right after we replace the file extent
4309 * items in the fs tree (which now point to the cloned data), we might
4310 * have a worker replace them with extent items relative to a write
4311 * operation that was issued before this clone operation (i.e. confront
4312 * with inode.c:btrfs_finish_ordered_io).
4313 */
4314 if (same_inode) {
4315 u64 lock_start = min_t(u64, off, destoff);
4316 u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
4317
4318 ret = lock_extent_range(src, lock_start, lock_len, true);
4319 } else {
4320 ret = btrfs_double_extent_lock(src, off, inode, destoff, len,
4321 true);
4322 }
4323 ASSERT(ret == 0);
4324 if (WARN_ON(ret)) {
4325 /* ranges in the io trees already unlocked */
4326 goto out_unlock;
4327 }
4328
4329 ret = btrfs_clone(src, inode, off, olen, len, destoff, 0);
4330
4331 if (same_inode) {
4332 u64 lock_start = min_t(u64, off, destoff);
4333 u64 lock_end = max_t(u64, off, destoff) + len - 1;
4334
4335 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
4336 } else {
4337 btrfs_double_extent_unlock(src, off, inode, destoff, len);
4338 }
4339 /*
4340 * Truncate page cache pages so that future reads will see the cloned
4341 * data immediately and not the previous data.
4342 */
4343 truncate_inode_pages_range(&inode->i_data,
4344 round_down(destoff, PAGE_SIZE),
4345 round_up(destoff + len, PAGE_SIZE) - 1);
4346 out_unlock:
4347 if (!same_inode)
4348 btrfs_double_inode_unlock(src, inode);
4349 else
4350 inode_unlock(src);
4351 return ret;
4352 }
4353
4354 int btrfs_clone_file_range(struct file *src_file, loff_t off,
4355 struct file *dst_file, loff_t destoff, u64 len)
4356 {
4357 return btrfs_clone_files(dst_file, src_file, off, len, destoff);
4358 }
4359
4360 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
4361 {
4362 struct inode *inode = file_inode(file);
4363 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4364 struct btrfs_root *root = BTRFS_I(inode)->root;
4365 struct btrfs_root *new_root;
4366 struct btrfs_dir_item *di;
4367 struct btrfs_trans_handle *trans;
4368 struct btrfs_path *path;
4369 struct btrfs_key location;
4370 struct btrfs_disk_key disk_key;
4371 u64 objectid = 0;
4372 u64 dir_id;
4373 int ret;
4374
4375 if (!capable(CAP_SYS_ADMIN))
4376 return -EPERM;
4377
4378 ret = mnt_want_write_file(file);
4379 if (ret)
4380 return ret;
4381
4382 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
4383 ret = -EFAULT;
4384 goto out;
4385 }
4386
4387 if (!objectid)
4388 objectid = BTRFS_FS_TREE_OBJECTID;
4389
4390 location.objectid = objectid;
4391 location.type = BTRFS_ROOT_ITEM_KEY;
4392 location.offset = (u64)-1;
4393
4394 new_root = btrfs_read_fs_root_no_name(fs_info, &location);
4395 if (IS_ERR(new_root)) {
4396 ret = PTR_ERR(new_root);
4397 goto out;
4398 }
4399 if (!is_fstree(new_root->objectid)) {
4400 ret = -ENOENT;
4401 goto out;
4402 }
4403
4404 path = btrfs_alloc_path();
4405 if (!path) {
4406 ret = -ENOMEM;
4407 goto out;
4408 }
4409 path->leave_spinning = 1;
4410
4411 trans = btrfs_start_transaction(root, 1);
4412 if (IS_ERR(trans)) {
4413 btrfs_free_path(path);
4414 ret = PTR_ERR(trans);
4415 goto out;
4416 }
4417
4418 dir_id = btrfs_super_root_dir(fs_info->super_copy);
4419 di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
4420 dir_id, "default", 7, 1);
4421 if (IS_ERR_OR_NULL(di)) {
4422 btrfs_free_path(path);
4423 btrfs_end_transaction(trans);
4424 btrfs_err(fs_info,
4425 "Umm, you don't have the default diritem, this isn't going to work");
4426 ret = -ENOENT;
4427 goto out;
4428 }
4429
4430 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
4431 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
4432 btrfs_mark_buffer_dirty(path->nodes[0]);
4433 btrfs_free_path(path);
4434
4435 btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
4436 btrfs_end_transaction(trans);
4437 out:
4438 mnt_drop_write_file(file);
4439 return ret;
4440 }
4441
4442 static void get_block_group_info(struct list_head *groups_list,
4443 struct btrfs_ioctl_space_info *space)
4444 {
4445 struct btrfs_block_group_cache *block_group;
4446
4447 space->total_bytes = 0;
4448 space->used_bytes = 0;
4449 space->flags = 0;
4450 list_for_each_entry(block_group, groups_list, list) {
4451 space->flags = block_group->flags;
4452 space->total_bytes += block_group->key.offset;
4453 space->used_bytes +=
4454 btrfs_block_group_used(&block_group->item);
4455 }
4456 }
4457
4458 static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
4459 void __user *arg)
4460 {
4461 struct btrfs_ioctl_space_args space_args;
4462 struct btrfs_ioctl_space_info space;
4463 struct btrfs_ioctl_space_info *dest;
4464 struct btrfs_ioctl_space_info *dest_orig;
4465 struct btrfs_ioctl_space_info __user *user_dest;
4466 struct btrfs_space_info *info;
4467 static const u64 types[] = {
4468 BTRFS_BLOCK_GROUP_DATA,
4469 BTRFS_BLOCK_GROUP_SYSTEM,
4470 BTRFS_BLOCK_GROUP_METADATA,
4471 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA
4472 };
4473 int num_types = 4;
4474 int alloc_size;
4475 int ret = 0;
4476 u64 slot_count = 0;
4477 int i, c;
4478
4479 if (copy_from_user(&space_args,
4480 (struct btrfs_ioctl_space_args __user *)arg,
4481 sizeof(space_args)))
4482 return -EFAULT;
4483
4484 for (i = 0; i < num_types; i++) {
4485 struct btrfs_space_info *tmp;
4486
4487 info = NULL;
4488 rcu_read_lock();
4489 list_for_each_entry_rcu(tmp, &fs_info->space_info,
4490 list) {
4491 if (tmp->flags == types[i]) {
4492 info = tmp;
4493 break;
4494 }
4495 }
4496 rcu_read_unlock();
4497
4498 if (!info)
4499 continue;
4500
4501 down_read(&info->groups_sem);
4502 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4503 if (!list_empty(&info->block_groups[c]))
4504 slot_count++;
4505 }
4506 up_read(&info->groups_sem);
4507 }
4508
4509 /*
4510 * Global block reserve, exported as a space_info
4511 */
4512 slot_count++;
4513
4514 /* space_slots == 0 means they are asking for a count */
4515 if (space_args.space_slots == 0) {
4516 space_args.total_spaces = slot_count;
4517 goto out;
4518 }
4519
4520 slot_count = min_t(u64, space_args.space_slots, slot_count);
4521
4522 alloc_size = sizeof(*dest) * slot_count;
4523
4524 /* we generally have at most 6 or so space infos, one for each raid
4525 * level. So, a whole page should be more than enough for everyone
4526 */
4527 if (alloc_size > PAGE_SIZE)
4528 return -ENOMEM;
4529
4530 space_args.total_spaces = 0;
4531 dest = kmalloc(alloc_size, GFP_KERNEL);
4532 if (!dest)
4533 return -ENOMEM;
4534 dest_orig = dest;
4535
4536 /* now we have a buffer to copy into */
4537 for (i = 0; i < num_types; i++) {
4538 struct btrfs_space_info *tmp;
4539
4540 if (!slot_count)
4541 break;
4542
4543 info = NULL;
4544 rcu_read_lock();
4545 list_for_each_entry_rcu(tmp, &fs_info->space_info,
4546 list) {
4547 if (tmp->flags == types[i]) {
4548 info = tmp;
4549 break;
4550 }
4551 }
4552 rcu_read_unlock();
4553
4554 if (!info)
4555 continue;
4556 down_read(&info->groups_sem);
4557 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4558 if (!list_empty(&info->block_groups[c])) {
4559 get_block_group_info(&info->block_groups[c],
4560 &space);
4561 memcpy(dest, &space, sizeof(space));
4562 dest++;
4563 space_args.total_spaces++;
4564 slot_count--;
4565 }
4566 if (!slot_count)
4567 break;
4568 }
4569 up_read(&info->groups_sem);
4570 }
4571
4572 /*
4573 * Add global block reserve
4574 */
4575 if (slot_count) {
4576 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
4577
4578 spin_lock(&block_rsv->lock);
4579 space.total_bytes = block_rsv->size;
4580 space.used_bytes = block_rsv->size - block_rsv->reserved;
4581 spin_unlock(&block_rsv->lock);
4582 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
4583 memcpy(dest, &space, sizeof(space));
4584 space_args.total_spaces++;
4585 }
4586
4587 user_dest = (struct btrfs_ioctl_space_info __user *)
4588 (arg + sizeof(struct btrfs_ioctl_space_args));
4589
4590 if (copy_to_user(user_dest, dest_orig, alloc_size))
4591 ret = -EFAULT;
4592
4593 kfree(dest_orig);
4594 out:
4595 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4596 ret = -EFAULT;
4597
4598 return ret;
4599 }
4600
4601 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4602 void __user *argp)
4603 {
4604 struct btrfs_trans_handle *trans;
4605 u64 transid;
4606 int ret;
4607
4608 trans = btrfs_attach_transaction_barrier(root);
4609 if (IS_ERR(trans)) {
4610 if (PTR_ERR(trans) != -ENOENT)
4611 return PTR_ERR(trans);
4612
4613 /* No running transaction, don't bother */
4614 transid = root->fs_info->last_trans_committed;
4615 goto out;
4616 }
4617 transid = trans->transid;
4618 ret = btrfs_commit_transaction_async(trans, 0);
4619 if (ret) {
4620 btrfs_end_transaction(trans);
4621 return ret;
4622 }
4623 out:
4624 if (argp)
4625 if (copy_to_user(argp, &transid, sizeof(transid)))
4626 return -EFAULT;
4627 return 0;
4628 }
4629
4630 static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,
4631 void __user *argp)
4632 {
4633 u64 transid;
4634
4635 if (argp) {
4636 if (copy_from_user(&transid, argp, sizeof(transid)))
4637 return -EFAULT;
4638 } else {
4639 transid = 0; /* current trans */
4640 }
4641 return btrfs_wait_for_commit(fs_info, transid);
4642 }
4643
4644 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4645 {
4646 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
4647 struct btrfs_ioctl_scrub_args *sa;
4648 int ret;
4649
4650 if (!capable(CAP_SYS_ADMIN))
4651 return -EPERM;
4652
4653 sa = memdup_user(arg, sizeof(*sa));
4654 if (IS_ERR(sa))
4655 return PTR_ERR(sa);
4656
4657 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4658 ret = mnt_want_write_file(file);
4659 if (ret)
4660 goto out;
4661 }
4662
4663 ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,
4664 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4665 0);
4666
4667 if (copy_to_user(arg, sa, sizeof(*sa)))
4668 ret = -EFAULT;
4669
4670 if (!(sa->flags & BTRFS_SCRUB_READONLY))
4671 mnt_drop_write_file(file);
4672 out:
4673 kfree(sa);
4674 return ret;
4675 }
4676
4677 static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)
4678 {
4679 if (!capable(CAP_SYS_ADMIN))
4680 return -EPERM;
4681
4682 return btrfs_scrub_cancel(fs_info);
4683 }
4684
4685 static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
4686 void __user *arg)
4687 {
4688 struct btrfs_ioctl_scrub_args *sa;
4689 int ret;
4690
4691 if (!capable(CAP_SYS_ADMIN))
4692 return -EPERM;
4693
4694 sa = memdup_user(arg, sizeof(*sa));
4695 if (IS_ERR(sa))
4696 return PTR_ERR(sa);
4697
4698 ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
4699
4700 if (copy_to_user(arg, sa, sizeof(*sa)))
4701 ret = -EFAULT;
4702
4703 kfree(sa);
4704 return ret;
4705 }
4706
4707 static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
4708 void __user *arg)
4709 {
4710 struct btrfs_ioctl_get_dev_stats *sa;
4711 int ret;
4712
4713 sa = memdup_user(arg, sizeof(*sa));
4714 if (IS_ERR(sa))
4715 return PTR_ERR(sa);
4716
4717 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4718 kfree(sa);
4719 return -EPERM;
4720 }
4721
4722 ret = btrfs_get_dev_stats(fs_info, sa);
4723
4724 if (copy_to_user(arg, sa, sizeof(*sa)))
4725 ret = -EFAULT;
4726
4727 kfree(sa);
4728 return ret;
4729 }
4730
4731 static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
4732 void __user *arg)
4733 {
4734 struct btrfs_ioctl_dev_replace_args *p;
4735 int ret;
4736
4737 if (!capable(CAP_SYS_ADMIN))
4738 return -EPERM;
4739
4740 p = memdup_user(arg, sizeof(*p));
4741 if (IS_ERR(p))
4742 return PTR_ERR(p);
4743
4744 switch (p->cmd) {
4745 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4746 if (sb_rdonly(fs_info->sb)) {
4747 ret = -EROFS;
4748 goto out;
4749 }
4750 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
4751 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4752 } else {
4753 ret = btrfs_dev_replace_by_ioctl(fs_info, p);
4754 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
4755 }
4756 break;
4757 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4758 btrfs_dev_replace_status(fs_info, p);
4759 ret = 0;
4760 break;
4761 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4762 p->result = btrfs_dev_replace_cancel(fs_info);
4763 ret = 0;
4764 break;
4765 default:
4766 ret = -EINVAL;
4767 break;
4768 }
4769
4770 if (copy_to_user(arg, p, sizeof(*p)))
4771 ret = -EFAULT;
4772 out:
4773 kfree(p);
4774 return ret;
4775 }
4776
4777 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4778 {
4779 int ret = 0;
4780 int i;
4781 u64 rel_ptr;
4782 int size;
4783 struct btrfs_ioctl_ino_path_args *ipa = NULL;
4784 struct inode_fs_paths *ipath = NULL;
4785 struct btrfs_path *path;
4786
4787 if (!capable(CAP_DAC_READ_SEARCH))
4788 return -EPERM;
4789
4790 path = btrfs_alloc_path();
4791 if (!path) {
4792 ret = -ENOMEM;
4793 goto out;
4794 }
4795
4796 ipa = memdup_user(arg, sizeof(*ipa));
4797 if (IS_ERR(ipa)) {
4798 ret = PTR_ERR(ipa);
4799 ipa = NULL;
4800 goto out;
4801 }
4802
4803 size = min_t(u32, ipa->size, 4096);
4804 ipath = init_ipath(size, root, path);
4805 if (IS_ERR(ipath)) {
4806 ret = PTR_ERR(ipath);
4807 ipath = NULL;
4808 goto out;
4809 }
4810
4811 ret = paths_from_inode(ipa->inum, ipath);
4812 if (ret < 0)
4813 goto out;
4814
4815 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4816 rel_ptr = ipath->fspath->val[i] -
4817 (u64)(unsigned long)ipath->fspath->val;
4818 ipath->fspath->val[i] = rel_ptr;
4819 }
4820
4821 ret = copy_to_user((void __user *)(unsigned long)ipa->fspath,
4822 ipath->fspath, size);
4823 if (ret) {
4824 ret = -EFAULT;
4825 goto out;
4826 }
4827
4828 out:
4829 btrfs_free_path(path);
4830 free_ipath(ipath);
4831 kfree(ipa);
4832
4833 return ret;
4834 }
4835
4836 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4837 {
4838 struct btrfs_data_container *inodes = ctx;
4839 const size_t c = 3 * sizeof(u64);
4840
4841 if (inodes->bytes_left >= c) {
4842 inodes->bytes_left -= c;
4843 inodes->val[inodes->elem_cnt] = inum;
4844 inodes->val[inodes->elem_cnt + 1] = offset;
4845 inodes->val[inodes->elem_cnt + 2] = root;
4846 inodes->elem_cnt += 3;
4847 } else {
4848 inodes->bytes_missing += c - inodes->bytes_left;
4849 inodes->bytes_left = 0;
4850 inodes->elem_missed += 3;
4851 }
4852
4853 return 0;
4854 }
4855
4856 static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,
4857 void __user *arg, int version)
4858 {
4859 int ret = 0;
4860 int size;
4861 struct btrfs_ioctl_logical_ino_args *loi;
4862 struct btrfs_data_container *inodes = NULL;
4863 struct btrfs_path *path = NULL;
4864 bool ignore_offset;
4865
4866 if (!capable(CAP_SYS_ADMIN))
4867 return -EPERM;
4868
4869 loi = memdup_user(arg, sizeof(*loi));
4870 if (IS_ERR(loi))
4871 return PTR_ERR(loi);
4872
4873 if (version == 1) {
4874 ignore_offset = false;
4875 size = min_t(u32, loi->size, SZ_64K);
4876 } else {
4877 /* All reserved bits must be 0 for now */
4878 if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) {
4879 ret = -EINVAL;
4880 goto out_loi;
4881 }
4882 /* Only accept flags we have defined so far */
4883 if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) {
4884 ret = -EINVAL;
4885 goto out_loi;
4886 }
4887 ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET;
4888 size = min_t(u32, loi->size, SZ_16M);
4889 }
4890
4891 path = btrfs_alloc_path();
4892 if (!path) {
4893 ret = -ENOMEM;
4894 goto out;
4895 }
4896
4897 inodes = init_data_container(size);
4898 if (IS_ERR(inodes)) {
4899 ret = PTR_ERR(inodes);
4900 inodes = NULL;
4901 goto out;
4902 }
4903
4904 ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
4905 build_ino_list, inodes, ignore_offset);
4906 if (ret == -EINVAL)
4907 ret = -ENOENT;
4908 if (ret < 0)
4909 goto out;
4910
4911 ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes,
4912 size);
4913 if (ret)
4914 ret = -EFAULT;
4915
4916 out:
4917 btrfs_free_path(path);
4918 kvfree(inodes);
4919 out_loi:
4920 kfree(loi);
4921
4922 return ret;
4923 }
4924
4925 void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info,
4926 struct btrfs_ioctl_balance_args *bargs)
4927 {
4928 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4929
4930 bargs->flags = bctl->flags;
4931
4932 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags))
4933 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4934 if (atomic_read(&fs_info->balance_pause_req))
4935 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4936 if (atomic_read(&fs_info->balance_cancel_req))
4937 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4938
4939 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4940 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4941 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4942
4943 spin_lock(&fs_info->balance_lock);
4944 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4945 spin_unlock(&fs_info->balance_lock);
4946 }
4947
4948 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4949 {
4950 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4951 struct btrfs_fs_info *fs_info = root->fs_info;
4952 struct btrfs_ioctl_balance_args *bargs;
4953 struct btrfs_balance_control *bctl;
4954 bool need_unlock; /* for mut. excl. ops lock */
4955 int ret;
4956
4957 if (!capable(CAP_SYS_ADMIN))
4958 return -EPERM;
4959
4960 ret = mnt_want_write_file(file);
4961 if (ret)
4962 return ret;
4963
4964 again:
4965 if (!test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
4966 mutex_lock(&fs_info->balance_mutex);
4967 need_unlock = true;
4968 goto locked;
4969 }
4970
4971 /*
4972 * mut. excl. ops lock is locked. Three possibilities:
4973 * (1) some other op is running
4974 * (2) balance is running
4975 * (3) balance is paused -- special case (think resume)
4976 */
4977 mutex_lock(&fs_info->balance_mutex);
4978 if (fs_info->balance_ctl) {
4979 /* this is either (2) or (3) */
4980 if (!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4981 mutex_unlock(&fs_info->balance_mutex);
4982 /*
4983 * Lock released to allow other waiters to continue,
4984 * we'll reexamine the status again.
4985 */
4986 mutex_lock(&fs_info->balance_mutex);
4987
4988 if (fs_info->balance_ctl &&
4989 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4990 /* this is (3) */
4991 need_unlock = false;
4992 goto locked;
4993 }
4994
4995 mutex_unlock(&fs_info->balance_mutex);
4996 goto again;
4997 } else {
4998 /* this is (2) */
4999 mutex_unlock(&fs_info->balance_mutex);
5000 ret = -EINPROGRESS;
5001 goto out;
5002 }
5003 } else {
5004 /* this is (1) */
5005 mutex_unlock(&fs_info->balance_mutex);
5006 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
5007 goto out;
5008 }
5009
5010 locked:
5011 BUG_ON(!test_bit(BTRFS_FS_EXCL_OP, &fs_info->flags));
5012
5013 if (arg) {
5014 bargs = memdup_user(arg, sizeof(*bargs));
5015 if (IS_ERR(bargs)) {
5016 ret = PTR_ERR(bargs);
5017 goto out_unlock;
5018 }
5019
5020 if (bargs->flags & BTRFS_BALANCE_RESUME) {
5021 if (!fs_info->balance_ctl) {
5022 ret = -ENOTCONN;
5023 goto out_bargs;
5024 }
5025
5026 bctl = fs_info->balance_ctl;
5027 spin_lock(&fs_info->balance_lock);
5028 bctl->flags |= BTRFS_BALANCE_RESUME;
5029 spin_unlock(&fs_info->balance_lock);
5030
5031 goto do_balance;
5032 }
5033 } else {
5034 bargs = NULL;
5035 }
5036
5037 if (fs_info->balance_ctl) {
5038 ret = -EINPROGRESS;
5039 goto out_bargs;
5040 }
5041
5042 bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
5043 if (!bctl) {
5044 ret = -ENOMEM;
5045 goto out_bargs;
5046 }
5047
5048 if (arg) {
5049 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
5050 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
5051 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
5052
5053 bctl->flags = bargs->flags;
5054 } else {
5055 /* balance everything - no filters */
5056 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
5057 }
5058
5059 if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
5060 ret = -EINVAL;
5061 goto out_bctl;
5062 }
5063
5064 do_balance:
5065 /*
5066 * Ownership of bctl and filesystem flag BTRFS_FS_EXCL_OP goes to
5067 * btrfs_balance. bctl is freed in reset_balance_state, or, if
5068 * restriper was paused all the way until unmount, in free_fs_info.
5069 * The flag should be cleared after reset_balance_state.
5070 */
5071 need_unlock = false;
5072
5073 ret = btrfs_balance(fs_info, bctl, bargs);
5074 bctl = NULL;
5075
5076 if (arg) {
5077 if (copy_to_user(arg, bargs, sizeof(*bargs)))
5078 ret = -EFAULT;
5079 }
5080
5081 out_bctl:
5082 kfree(bctl);
5083 out_bargs:
5084 kfree(bargs);
5085 out_unlock:
5086 mutex_unlock(&fs_info->balance_mutex);
5087 if (need_unlock)
5088 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
5089 out:
5090 mnt_drop_write_file(file);
5091 return ret;
5092 }
5093
5094 static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
5095 {
5096 if (!capable(CAP_SYS_ADMIN))
5097 return -EPERM;
5098
5099 switch (cmd) {
5100 case BTRFS_BALANCE_CTL_PAUSE:
5101 return btrfs_pause_balance(fs_info);
5102 case BTRFS_BALANCE_CTL_CANCEL:
5103 return btrfs_cancel_balance(fs_info);
5104 }
5105
5106 return -EINVAL;
5107 }
5108
5109 static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
5110 void __user *arg)
5111 {
5112 struct btrfs_ioctl_balance_args *bargs;
5113 int ret = 0;
5114
5115 if (!capable(CAP_SYS_ADMIN))
5116 return -EPERM;
5117
5118 mutex_lock(&fs_info->balance_mutex);
5119 if (!fs_info->balance_ctl) {
5120 ret = -ENOTCONN;
5121 goto out;
5122 }
5123
5124 bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
5125 if (!bargs) {
5126 ret = -ENOMEM;
5127 goto out;
5128 }
5129
5130 btrfs_update_ioctl_balance_args(fs_info, bargs);
5131
5132 if (copy_to_user(arg, bargs, sizeof(*bargs)))
5133 ret = -EFAULT;
5134
5135 kfree(bargs);
5136 out:
5137 mutex_unlock(&fs_info->balance_mutex);
5138 return ret;
5139 }
5140
5141 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
5142 {
5143 struct inode *inode = file_inode(file);
5144 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5145 struct btrfs_ioctl_quota_ctl_args *sa;
5146 int ret;
5147
5148 if (!capable(CAP_SYS_ADMIN))
5149 return -EPERM;
5150
5151 ret = mnt_want_write_file(file);
5152 if (ret)
5153 return ret;
5154
5155 sa = memdup_user(arg, sizeof(*sa));
5156 if (IS_ERR(sa)) {
5157 ret = PTR_ERR(sa);
5158 goto drop_write;
5159 }
5160
5161 down_write(&fs_info->subvol_sem);
5162
5163 switch (sa->cmd) {
5164 case BTRFS_QUOTA_CTL_ENABLE:
5165 ret = btrfs_quota_enable(fs_info);
5166 break;
5167 case BTRFS_QUOTA_CTL_DISABLE:
5168 ret = btrfs_quota_disable(fs_info);
5169 break;
5170 default:
5171 ret = -EINVAL;
5172 break;
5173 }
5174
5175 kfree(sa);
5176 up_write(&fs_info->subvol_sem);
5177 drop_write:
5178 mnt_drop_write_file(file);
5179 return ret;
5180 }
5181
5182 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
5183 {
5184 struct inode *inode = file_inode(file);
5185 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5186 struct btrfs_root *root = BTRFS_I(inode)->root;
5187 struct btrfs_ioctl_qgroup_assign_args *sa;
5188 struct btrfs_trans_handle *trans;
5189 int ret;
5190 int err;
5191
5192 if (!capable(CAP_SYS_ADMIN))
5193 return -EPERM;
5194
5195 ret = mnt_want_write_file(file);
5196 if (ret)
5197 return ret;
5198
5199 sa = memdup_user(arg, sizeof(*sa));
5200 if (IS_ERR(sa)) {
5201 ret = PTR_ERR(sa);
5202 goto drop_write;
5203 }
5204
5205 trans = btrfs_join_transaction(root);
5206 if (IS_ERR(trans)) {
5207 ret = PTR_ERR(trans);
5208 goto out;
5209 }
5210
5211 if (sa->assign) {
5212 ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst);
5213 } else {
5214 ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst);
5215 }
5216
5217 /* update qgroup status and info */
5218 err = btrfs_run_qgroups(trans);
5219 if (err < 0)
5220 btrfs_handle_fs_error(fs_info, err,
5221 "failed to update qgroup status and info");
5222 err = btrfs_end_transaction(trans);
5223 if (err && !ret)
5224 ret = err;
5225
5226 out:
5227 kfree(sa);
5228 drop_write:
5229 mnt_drop_write_file(file);
5230 return ret;
5231 }
5232
5233 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
5234 {
5235 struct inode *inode = file_inode(file);
5236 struct btrfs_root *root = BTRFS_I(inode)->root;
5237 struct btrfs_ioctl_qgroup_create_args *sa;
5238 struct btrfs_trans_handle *trans;
5239 int ret;
5240 int err;
5241
5242 if (!capable(CAP_SYS_ADMIN))
5243 return -EPERM;
5244
5245 ret = mnt_want_write_file(file);
5246 if (ret)
5247 return ret;
5248
5249 sa = memdup_user(arg, sizeof(*sa));
5250 if (IS_ERR(sa)) {
5251 ret = PTR_ERR(sa);
5252 goto drop_write;
5253 }
5254
5255 if (!sa->qgroupid) {
5256 ret = -EINVAL;
5257 goto out;
5258 }
5259
5260 trans = btrfs_join_transaction(root);
5261 if (IS_ERR(trans)) {
5262 ret = PTR_ERR(trans);
5263 goto out;
5264 }
5265
5266 if (sa->create) {
5267 ret = btrfs_create_qgroup(trans, sa->qgroupid);
5268 } else {
5269 ret = btrfs_remove_qgroup(trans, sa->qgroupid);
5270 }
5271
5272 err = btrfs_end_transaction(trans);
5273 if (err && !ret)
5274 ret = err;
5275
5276 out:
5277 kfree(sa);
5278 drop_write:
5279 mnt_drop_write_file(file);
5280 return ret;
5281 }
5282
5283 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
5284 {
5285 struct inode *inode = file_inode(file);
5286 struct btrfs_root *root = BTRFS_I(inode)->root;
5287 struct btrfs_ioctl_qgroup_limit_args *sa;
5288 struct btrfs_trans_handle *trans;
5289 int ret;
5290 int err;
5291 u64 qgroupid;
5292
5293 if (!capable(CAP_SYS_ADMIN))
5294 return -EPERM;
5295
5296 ret = mnt_want_write_file(file);
5297 if (ret)
5298 return ret;
5299
5300 sa = memdup_user(arg, sizeof(*sa));
5301 if (IS_ERR(sa)) {
5302 ret = PTR_ERR(sa);
5303 goto drop_write;
5304 }
5305
5306 trans = btrfs_join_transaction(root);
5307 if (IS_ERR(trans)) {
5308 ret = PTR_ERR(trans);
5309 goto out;
5310 }
5311
5312 qgroupid = sa->qgroupid;
5313 if (!qgroupid) {
5314 /* take the current subvol as qgroup */
5315 qgroupid = root->root_key.objectid;
5316 }
5317
5318 ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim);
5319
5320 err = btrfs_end_transaction(trans);
5321 if (err && !ret)
5322 ret = err;
5323
5324 out:
5325 kfree(sa);
5326 drop_write:
5327 mnt_drop_write_file(file);
5328 return ret;
5329 }
5330
5331 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
5332 {
5333 struct inode *inode = file_inode(file);
5334 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5335 struct btrfs_ioctl_quota_rescan_args *qsa;
5336 int ret;
5337
5338 if (!capable(CAP_SYS_ADMIN))
5339 return -EPERM;
5340
5341 ret = mnt_want_write_file(file);
5342 if (ret)
5343 return ret;
5344
5345 qsa = memdup_user(arg, sizeof(*qsa));
5346 if (IS_ERR(qsa)) {
5347 ret = PTR_ERR(qsa);
5348 goto drop_write;
5349 }
5350
5351 if (qsa->flags) {
5352 ret = -EINVAL;
5353 goto out;
5354 }
5355
5356 ret = btrfs_qgroup_rescan(fs_info);
5357
5358 out:
5359 kfree(qsa);
5360 drop_write:
5361 mnt_drop_write_file(file);
5362 return ret;
5363 }
5364
5365 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
5366 {
5367 struct inode *inode = file_inode(file);
5368 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5369 struct btrfs_ioctl_quota_rescan_args *qsa;
5370 int ret = 0;
5371
5372 if (!capable(CAP_SYS_ADMIN))
5373 return -EPERM;
5374
5375 qsa = kzalloc(sizeof(*qsa), GFP_KERNEL);
5376 if (!qsa)
5377 return -ENOMEM;
5378
5379 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
5380 qsa->flags = 1;
5381 qsa->progress = fs_info->qgroup_rescan_progress.objectid;
5382 }
5383
5384 if (copy_to_user(arg, qsa, sizeof(*qsa)))
5385 ret = -EFAULT;
5386
5387 kfree(qsa);
5388 return ret;
5389 }
5390
5391 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
5392 {
5393 struct inode *inode = file_inode(file);
5394 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5395
5396 if (!capable(CAP_SYS_ADMIN))
5397 return -EPERM;
5398
5399 return btrfs_qgroup_wait_for_completion(fs_info, true);
5400 }
5401
5402 static long _btrfs_ioctl_set_received_subvol(struct file *file,
5403 struct btrfs_ioctl_received_subvol_args *sa)
5404 {
5405 struct inode *inode = file_inode(file);
5406 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5407 struct btrfs_root *root = BTRFS_I(inode)->root;
5408 struct btrfs_root_item *root_item = &root->root_item;
5409 struct btrfs_trans_handle *trans;
5410 struct timespec64 ct = current_time(inode);
5411 int ret = 0;
5412 int received_uuid_changed;
5413
5414 if (!inode_owner_or_capable(inode))
5415 return -EPERM;
5416
5417 ret = mnt_want_write_file(file);
5418 if (ret < 0)
5419 return ret;
5420
5421 down_write(&fs_info->subvol_sem);
5422
5423 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
5424 ret = -EINVAL;
5425 goto out;
5426 }
5427
5428 if (btrfs_root_readonly(root)) {
5429 ret = -EROFS;
5430 goto out;
5431 }
5432
5433 /*
5434 * 1 - root item
5435 * 2 - uuid items (received uuid + subvol uuid)
5436 */
5437 trans = btrfs_start_transaction(root, 3);
5438 if (IS_ERR(trans)) {
5439 ret = PTR_ERR(trans);
5440 trans = NULL;
5441 goto out;
5442 }
5443
5444 sa->rtransid = trans->transid;
5445 sa->rtime.sec = ct.tv_sec;
5446 sa->rtime.nsec = ct.tv_nsec;
5447
5448 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
5449 BTRFS_UUID_SIZE);
5450 if (received_uuid_changed &&
5451 !btrfs_is_empty_uuid(root_item->received_uuid)) {
5452 ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid,
5453 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5454 root->root_key.objectid);
5455 if (ret && ret != -ENOENT) {
5456 btrfs_abort_transaction(trans, ret);
5457 btrfs_end_transaction(trans);
5458 goto out;
5459 }
5460 }
5461 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
5462 btrfs_set_root_stransid(root_item, sa->stransid);
5463 btrfs_set_root_rtransid(root_item, sa->rtransid);
5464 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
5465 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
5466 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
5467 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
5468
5469 ret = btrfs_update_root(trans, fs_info->tree_root,
5470 &root->root_key, &root->root_item);
5471 if (ret < 0) {
5472 btrfs_end_transaction(trans);
5473 goto out;
5474 }
5475 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
5476 ret = btrfs_uuid_tree_add(trans, sa->uuid,
5477 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5478 root->root_key.objectid);
5479 if (ret < 0 && ret != -EEXIST) {
5480 btrfs_abort_transaction(trans, ret);
5481 btrfs_end_transaction(trans);
5482 goto out;
5483 }
5484 }
5485 ret = btrfs_commit_transaction(trans);
5486 out:
5487 up_write(&fs_info->subvol_sem);
5488 mnt_drop_write_file(file);
5489 return ret;
5490 }
5491
5492 #ifdef CONFIG_64BIT
5493 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
5494 void __user *arg)
5495 {
5496 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
5497 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
5498 int ret = 0;
5499
5500 args32 = memdup_user(arg, sizeof(*args32));
5501 if (IS_ERR(args32))
5502 return PTR_ERR(args32);
5503
5504 args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
5505 if (!args64) {
5506 ret = -ENOMEM;
5507 goto out;
5508 }
5509
5510 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
5511 args64->stransid = args32->stransid;
5512 args64->rtransid = args32->rtransid;
5513 args64->stime.sec = args32->stime.sec;
5514 args64->stime.nsec = args32->stime.nsec;
5515 args64->rtime.sec = args32->rtime.sec;
5516 args64->rtime.nsec = args32->rtime.nsec;
5517 args64->flags = args32->flags;
5518
5519 ret = _btrfs_ioctl_set_received_subvol(file, args64);
5520 if (ret)
5521 goto out;
5522
5523 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
5524 args32->stransid = args64->stransid;
5525 args32->rtransid = args64->rtransid;
5526 args32->stime.sec = args64->stime.sec;
5527 args32->stime.nsec = args64->stime.nsec;
5528 args32->rtime.sec = args64->rtime.sec;
5529 args32->rtime.nsec = args64->rtime.nsec;
5530 args32->flags = args64->flags;
5531
5532 ret = copy_to_user(arg, args32, sizeof(*args32));
5533 if (ret)
5534 ret = -EFAULT;
5535
5536 out:
5537 kfree(args32);
5538 kfree(args64);
5539 return ret;
5540 }
5541 #endif
5542
5543 static long btrfs_ioctl_set_received_subvol(struct file *file,
5544 void __user *arg)
5545 {
5546 struct btrfs_ioctl_received_subvol_args *sa = NULL;
5547 int ret = 0;
5548
5549 sa = memdup_user(arg, sizeof(*sa));
5550 if (IS_ERR(sa))
5551 return PTR_ERR(sa);
5552
5553 ret = _btrfs_ioctl_set_received_subvol(file, sa);
5554
5555 if (ret)
5556 goto out;
5557
5558 ret = copy_to_user(arg, sa, sizeof(*sa));
5559 if (ret)
5560 ret = -EFAULT;
5561
5562 out:
5563 kfree(sa);
5564 return ret;
5565 }
5566
5567 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
5568 {
5569 struct inode *inode = file_inode(file);
5570 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5571 size_t len;
5572 int ret;
5573 char label[BTRFS_LABEL_SIZE];
5574
5575 spin_lock(&fs_info->super_lock);
5576 memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5577 spin_unlock(&fs_info->super_lock);
5578
5579 len = strnlen(label, BTRFS_LABEL_SIZE);
5580
5581 if (len == BTRFS_LABEL_SIZE) {
5582 btrfs_warn(fs_info,
5583 "label is too long, return the first %zu bytes",
5584 --len);
5585 }
5586
5587 ret = copy_to_user(arg, label, len);
5588
5589 return ret ? -EFAULT : 0;
5590 }
5591
5592 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5593 {
5594 struct inode *inode = file_inode(file);
5595 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5596 struct btrfs_root *root = BTRFS_I(inode)->root;
5597 struct btrfs_super_block *super_block = fs_info->super_copy;
5598 struct btrfs_trans_handle *trans;
5599 char label[BTRFS_LABEL_SIZE];
5600 int ret;
5601
5602 if (!capable(CAP_SYS_ADMIN))
5603 return -EPERM;
5604
5605 if (copy_from_user(label, arg, sizeof(label)))
5606 return -EFAULT;
5607
5608 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5609 btrfs_err(fs_info,
5610 "unable to set label with more than %d bytes",
5611 BTRFS_LABEL_SIZE - 1);
5612 return -EINVAL;
5613 }
5614
5615 ret = mnt_want_write_file(file);
5616 if (ret)
5617 return ret;
5618
5619 trans = btrfs_start_transaction(root, 0);
5620 if (IS_ERR(trans)) {
5621 ret = PTR_ERR(trans);
5622 goto out_unlock;
5623 }
5624
5625 spin_lock(&fs_info->super_lock);
5626 strcpy(super_block->label, label);
5627 spin_unlock(&fs_info->super_lock);
5628 ret = btrfs_commit_transaction(trans);
5629
5630 out_unlock:
5631 mnt_drop_write_file(file);
5632 return ret;
5633 }
5634
5635 #define INIT_FEATURE_FLAGS(suffix) \
5636 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5637 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5638 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5639
5640 int btrfs_ioctl_get_supported_features(void __user *arg)
5641 {
5642 static const struct btrfs_ioctl_feature_flags features[3] = {
5643 INIT_FEATURE_FLAGS(SUPP),
5644 INIT_FEATURE_FLAGS(SAFE_SET),
5645 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5646 };
5647
5648 if (copy_to_user(arg, &features, sizeof(features)))
5649 return -EFAULT;
5650
5651 return 0;
5652 }
5653
5654 static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5655 {
5656 struct inode *inode = file_inode(file);
5657 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5658 struct btrfs_super_block *super_block = fs_info->super_copy;
5659 struct btrfs_ioctl_feature_flags features;
5660
5661 features.compat_flags = btrfs_super_compat_flags(super_block);
5662 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5663 features.incompat_flags = btrfs_super_incompat_flags(super_block);
5664
5665 if (copy_to_user(arg, &features, sizeof(features)))
5666 return -EFAULT;
5667
5668 return 0;
5669 }
5670
5671 static int check_feature_bits(struct btrfs_fs_info *fs_info,
5672 enum btrfs_feature_set set,
5673 u64 change_mask, u64 flags, u64 supported_flags,
5674 u64 safe_set, u64 safe_clear)
5675 {
5676 const char *type = btrfs_feature_set_names[set];
5677 char *names;
5678 u64 disallowed, unsupported;
5679 u64 set_mask = flags & change_mask;
5680 u64 clear_mask = ~flags & change_mask;
5681
5682 unsupported = set_mask & ~supported_flags;
5683 if (unsupported) {
5684 names = btrfs_printable_features(set, unsupported);
5685 if (names) {
5686 btrfs_warn(fs_info,
5687 "this kernel does not support the %s feature bit%s",
5688 names, strchr(names, ',') ? "s" : "");
5689 kfree(names);
5690 } else
5691 btrfs_warn(fs_info,
5692 "this kernel does not support %s bits 0x%llx",
5693 type, unsupported);
5694 return -EOPNOTSUPP;
5695 }
5696
5697 disallowed = set_mask & ~safe_set;
5698 if (disallowed) {
5699 names = btrfs_printable_features(set, disallowed);
5700 if (names) {
5701 btrfs_warn(fs_info,
5702 "can't set the %s feature bit%s while mounted",
5703 names, strchr(names, ',') ? "s" : "");
5704 kfree(names);
5705 } else
5706 btrfs_warn(fs_info,
5707 "can't set %s bits 0x%llx while mounted",
5708 type, disallowed);
5709 return -EPERM;
5710 }
5711
5712 disallowed = clear_mask & ~safe_clear;
5713 if (disallowed) {
5714 names = btrfs_printable_features(set, disallowed);
5715 if (names) {
5716 btrfs_warn(fs_info,
5717 "can't clear the %s feature bit%s while mounted",
5718 names, strchr(names, ',') ? "s" : "");
5719 kfree(names);
5720 } else
5721 btrfs_warn(fs_info,
5722 "can't clear %s bits 0x%llx while mounted",
5723 type, disallowed);
5724 return -EPERM;
5725 }
5726
5727 return 0;
5728 }
5729
5730 #define check_feature(fs_info, change_mask, flags, mask_base) \
5731 check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags, \
5732 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
5733 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
5734 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5735
5736 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5737 {
5738 struct inode *inode = file_inode(file);
5739 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5740 struct btrfs_root *root = BTRFS_I(inode)->root;
5741 struct btrfs_super_block *super_block = fs_info->super_copy;
5742 struct btrfs_ioctl_feature_flags flags[2];
5743 struct btrfs_trans_handle *trans;
5744 u64 newflags;
5745 int ret;
5746
5747 if (!capable(CAP_SYS_ADMIN))
5748 return -EPERM;
5749
5750 if (copy_from_user(flags, arg, sizeof(flags)))
5751 return -EFAULT;
5752
5753 /* Nothing to do */
5754 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5755 !flags[0].incompat_flags)
5756 return 0;
5757
5758 ret = check_feature(fs_info, flags[0].compat_flags,
5759 flags[1].compat_flags, COMPAT);
5760 if (ret)
5761 return ret;
5762
5763 ret = check_feature(fs_info, flags[0].compat_ro_flags,
5764 flags[1].compat_ro_flags, COMPAT_RO);
5765 if (ret)
5766 return ret;
5767
5768 ret = check_feature(fs_info, flags[0].incompat_flags,
5769 flags[1].incompat_flags, INCOMPAT);
5770 if (ret)
5771 return ret;
5772
5773 ret = mnt_want_write_file(file);
5774 if (ret)
5775 return ret;
5776
5777 trans = btrfs_start_transaction(root, 0);
5778 if (IS_ERR(trans)) {
5779 ret = PTR_ERR(trans);
5780 goto out_drop_write;
5781 }
5782
5783 spin_lock(&fs_info->super_lock);
5784 newflags = btrfs_super_compat_flags(super_block);
5785 newflags |= flags[0].compat_flags & flags[1].compat_flags;
5786 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5787 btrfs_set_super_compat_flags(super_block, newflags);
5788
5789 newflags = btrfs_super_compat_ro_flags(super_block);
5790 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5791 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5792 btrfs_set_super_compat_ro_flags(super_block, newflags);
5793
5794 newflags = btrfs_super_incompat_flags(super_block);
5795 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5796 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5797 btrfs_set_super_incompat_flags(super_block, newflags);
5798 spin_unlock(&fs_info->super_lock);
5799
5800 ret = btrfs_commit_transaction(trans);
5801 out_drop_write:
5802 mnt_drop_write_file(file);
5803
5804 return ret;
5805 }
5806
5807 static int _btrfs_ioctl_send(struct file *file, void __user *argp, bool compat)
5808 {
5809 struct btrfs_ioctl_send_args *arg;
5810 int ret;
5811
5812 if (compat) {
5813 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
5814 struct btrfs_ioctl_send_args_32 args32;
5815
5816 ret = copy_from_user(&args32, argp, sizeof(args32));
5817 if (ret)
5818 return -EFAULT;
5819 arg = kzalloc(sizeof(*arg), GFP_KERNEL);
5820 if (!arg)
5821 return -ENOMEM;
5822 arg->send_fd = args32.send_fd;
5823 arg->clone_sources_count = args32.clone_sources_count;
5824 arg->clone_sources = compat_ptr(args32.clone_sources);
5825 arg->parent_root = args32.parent_root;
5826 arg->flags = args32.flags;
5827 memcpy(arg->reserved, args32.reserved,
5828 sizeof(args32.reserved));
5829 #else
5830 return -ENOTTY;
5831 #endif
5832 } else {
5833 arg = memdup_user(argp, sizeof(*arg));
5834 if (IS_ERR(arg))
5835 return PTR_ERR(arg);
5836 }
5837 ret = btrfs_ioctl_send(file, arg);
5838 kfree(arg);
5839 return ret;
5840 }
5841
5842 long btrfs_ioctl(struct file *file, unsigned int
5843 cmd, unsigned long arg)
5844 {
5845 struct inode *inode = file_inode(file);
5846 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5847 struct btrfs_root *root = BTRFS_I(inode)->root;
5848 void __user *argp = (void __user *)arg;
5849
5850 switch (cmd) {
5851 case FS_IOC_GETFLAGS:
5852 return btrfs_ioctl_getflags(file, argp);
5853 case FS_IOC_SETFLAGS:
5854 return btrfs_ioctl_setflags(file, argp);
5855 case FS_IOC_GETVERSION:
5856 return btrfs_ioctl_getversion(file, argp);
5857 case FITRIM:
5858 return btrfs_ioctl_fitrim(file, argp);
5859 case BTRFS_IOC_SNAP_CREATE:
5860 return btrfs_ioctl_snap_create(file, argp, 0);
5861 case BTRFS_IOC_SNAP_CREATE_V2:
5862 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5863 case BTRFS_IOC_SUBVOL_CREATE:
5864 return btrfs_ioctl_snap_create(file, argp, 1);
5865 case BTRFS_IOC_SUBVOL_CREATE_V2:
5866 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5867 case BTRFS_IOC_SNAP_DESTROY:
5868 return btrfs_ioctl_snap_destroy(file, argp);
5869 case BTRFS_IOC_SUBVOL_GETFLAGS:
5870 return btrfs_ioctl_subvol_getflags(file, argp);
5871 case BTRFS_IOC_SUBVOL_SETFLAGS:
5872 return btrfs_ioctl_subvol_setflags(file, argp);
5873 case BTRFS_IOC_DEFAULT_SUBVOL:
5874 return btrfs_ioctl_default_subvol(file, argp);
5875 case BTRFS_IOC_DEFRAG:
5876 return btrfs_ioctl_defrag(file, NULL);
5877 case BTRFS_IOC_DEFRAG_RANGE:
5878 return btrfs_ioctl_defrag(file, argp);
5879 case BTRFS_IOC_RESIZE:
5880 return btrfs_ioctl_resize(file, argp);
5881 case BTRFS_IOC_ADD_DEV:
5882 return btrfs_ioctl_add_dev(fs_info, argp);
5883 case BTRFS_IOC_RM_DEV:
5884 return btrfs_ioctl_rm_dev(file, argp);
5885 case BTRFS_IOC_RM_DEV_V2:
5886 return btrfs_ioctl_rm_dev_v2(file, argp);
5887 case BTRFS_IOC_FS_INFO:
5888 return btrfs_ioctl_fs_info(fs_info, argp);
5889 case BTRFS_IOC_DEV_INFO:
5890 return btrfs_ioctl_dev_info(fs_info, argp);
5891 case BTRFS_IOC_BALANCE:
5892 return btrfs_ioctl_balance(file, NULL);
5893 case BTRFS_IOC_TREE_SEARCH:
5894 return btrfs_ioctl_tree_search(file, argp);
5895 case BTRFS_IOC_TREE_SEARCH_V2:
5896 return btrfs_ioctl_tree_search_v2(file, argp);
5897 case BTRFS_IOC_INO_LOOKUP:
5898 return btrfs_ioctl_ino_lookup(file, argp);
5899 case BTRFS_IOC_INO_PATHS:
5900 return btrfs_ioctl_ino_to_path(root, argp);
5901 case BTRFS_IOC_LOGICAL_INO:
5902 return btrfs_ioctl_logical_to_ino(fs_info, argp, 1);
5903 case BTRFS_IOC_LOGICAL_INO_V2:
5904 return btrfs_ioctl_logical_to_ino(fs_info, argp, 2);
5905 case BTRFS_IOC_SPACE_INFO:
5906 return btrfs_ioctl_space_info(fs_info, argp);
5907 case BTRFS_IOC_SYNC: {
5908 int ret;
5909
5910 ret = btrfs_start_delalloc_roots(fs_info, -1);
5911 if (ret)
5912 return ret;
5913 ret = btrfs_sync_fs(inode->i_sb, 1);
5914 /*
5915 * The transaction thread may want to do more work,
5916 * namely it pokes the cleaner kthread that will start
5917 * processing uncleaned subvols.
5918 */
5919 wake_up_process(fs_info->transaction_kthread);
5920 return ret;
5921 }
5922 case BTRFS_IOC_START_SYNC:
5923 return btrfs_ioctl_start_sync(root, argp);
5924 case BTRFS_IOC_WAIT_SYNC:
5925 return btrfs_ioctl_wait_sync(fs_info, argp);
5926 case BTRFS_IOC_SCRUB:
5927 return btrfs_ioctl_scrub(file, argp);
5928 case BTRFS_IOC_SCRUB_CANCEL:
5929 return btrfs_ioctl_scrub_cancel(fs_info);
5930 case BTRFS_IOC_SCRUB_PROGRESS:
5931 return btrfs_ioctl_scrub_progress(fs_info, argp);
5932 case BTRFS_IOC_BALANCE_V2:
5933 return btrfs_ioctl_balance(file, argp);
5934 case BTRFS_IOC_BALANCE_CTL:
5935 return btrfs_ioctl_balance_ctl(fs_info, arg);
5936 case BTRFS_IOC_BALANCE_PROGRESS:
5937 return btrfs_ioctl_balance_progress(fs_info, argp);
5938 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5939 return btrfs_ioctl_set_received_subvol(file, argp);
5940 #ifdef CONFIG_64BIT
5941 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5942 return btrfs_ioctl_set_received_subvol_32(file, argp);
5943 #endif
5944 case BTRFS_IOC_SEND:
5945 return _btrfs_ioctl_send(file, argp, false);
5946 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
5947 case BTRFS_IOC_SEND_32:
5948 return _btrfs_ioctl_send(file, argp, true);
5949 #endif
5950 case BTRFS_IOC_GET_DEV_STATS:
5951 return btrfs_ioctl_get_dev_stats(fs_info, argp);
5952 case BTRFS_IOC_QUOTA_CTL:
5953 return btrfs_ioctl_quota_ctl(file, argp);
5954 case BTRFS_IOC_QGROUP_ASSIGN:
5955 return btrfs_ioctl_qgroup_assign(file, argp);
5956 case BTRFS_IOC_QGROUP_CREATE:
5957 return btrfs_ioctl_qgroup_create(file, argp);
5958 case BTRFS_IOC_QGROUP_LIMIT:
5959 return btrfs_ioctl_qgroup_limit(file, argp);
5960 case BTRFS_IOC_QUOTA_RESCAN:
5961 return btrfs_ioctl_quota_rescan(file, argp);
5962 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5963 return btrfs_ioctl_quota_rescan_status(file, argp);
5964 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5965 return btrfs_ioctl_quota_rescan_wait(file, argp);
5966 case BTRFS_IOC_DEV_REPLACE:
5967 return btrfs_ioctl_dev_replace(fs_info, argp);
5968 case BTRFS_IOC_GET_FSLABEL:
5969 return btrfs_ioctl_get_fslabel(file, argp);
5970 case BTRFS_IOC_SET_FSLABEL:
5971 return btrfs_ioctl_set_fslabel(file, argp);
5972 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5973 return btrfs_ioctl_get_supported_features(argp);
5974 case BTRFS_IOC_GET_FEATURES:
5975 return btrfs_ioctl_get_features(file, argp);
5976 case BTRFS_IOC_SET_FEATURES:
5977 return btrfs_ioctl_set_features(file, argp);
5978 case FS_IOC_FSGETXATTR:
5979 return btrfs_ioctl_fsgetxattr(file, argp);
5980 case FS_IOC_FSSETXATTR:
5981 return btrfs_ioctl_fssetxattr(file, argp);
5982 case BTRFS_IOC_GET_SUBVOL_INFO:
5983 return btrfs_ioctl_get_subvol_info(file, argp);
5984 case BTRFS_IOC_GET_SUBVOL_ROOTREF:
5985 return btrfs_ioctl_get_subvol_rootref(file, argp);
5986 case BTRFS_IOC_INO_LOOKUP_USER:
5987 return btrfs_ioctl_ino_lookup_user(file, argp);
5988 }
5989
5990 return -ENOTTY;
5991 }
5992
5993 #ifdef CONFIG_COMPAT
5994 long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
5995 {
5996 /*
5997 * These all access 32-bit values anyway so no further
5998 * handling is necessary.
5999 */
6000 switch (cmd) {
6001 case FS_IOC32_GETFLAGS:
6002 cmd = FS_IOC_GETFLAGS;
6003 break;
6004 case FS_IOC32_SETFLAGS:
6005 cmd = FS_IOC_SETFLAGS;
6006 break;
6007 case FS_IOC32_GETVERSION:
6008 cmd = FS_IOC_GETVERSION;
6009 break;
6010 }
6011
6012 return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
6013 }
6014 #endif
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