1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
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"
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__));
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__));
68 #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
69 struct btrfs_ioctl_received_subvol_args_32)
70 #endif
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__));
82 #define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \
83 struct btrfs_ioctl_send_args_32)
84 #endif
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);
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 }
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;
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;
125 if (flags & BTRFS_INODE_NOCOMPRESS)
126 iflags |= FS_NOCOMP_FL;
127 else if (flags & BTRFS_INODE_COMPRESS)
128 iflags |= FS_COMPR_FL;
130 return iflags;
131 }
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;
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;
152 set_mask_bits(&inode->i_flags,
153 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
154 new_fl);
155 }
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);
162 if (copy_to_user(arg, &flags, sizeof(flags)))
163 return -EFAULT;
164 return 0;
165 }
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;
177 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
178 return -EINVAL;
180 return 0;
181 }
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;
196 if (!inode_owner_or_capable(inode))
197 return -EPERM;
199 if (btrfs_root_readonly(root))
200 return -EROFS;
202 if (copy_from_user(&fsflags, arg, sizeof(fsflags)))
203 return -EFAULT;
205 ret = check_fsflags(fsflags);
206 if (ret)
207 return ret;
209 ret = mnt_want_write_file(file);
210 if (ret)
211 return ret;
213 inode_lock(inode);
215 old_flags = binode->flags;
216 old_i_flags = inode->i_flags;
217 mode = inode->i_mode;
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 }
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 }
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;
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;
293 binode->flags |= BTRFS_INODE_COMPRESS;
294 binode->flags &= ~BTRFS_INODE_NOCOMPRESS;
296 comp = btrfs_compress_type2str(fs_info->compress_type);
297 if (!comp || comp[0] == 0)
298 comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);
300 ret = btrfs_set_prop(inode, "btrfs.compression",
301 comp, strlen(comp), 0);
302 if (ret)
303 goto out_drop;
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 }
312 trans = btrfs_start_transaction(root, 1);
313 if (IS_ERR(trans)) {
314 ret = PTR_ERR(trans);
315 goto out_drop;
316 }
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);
323 btrfs_end_transaction(trans);
324 out_drop:
325 if (ret) {
326 binode->flags = old_flags;
327 inode->i_flags = old_i_flags;
328 }
330 out_unlock:
331 inode_unlock(inode);
332 mnt_drop_write_file(file);
333 return ret;
334 }
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;
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;
356 return xflags;
357 }
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 }
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;
377 memset(&fa, 0, sizeof(fa));
378 fa.fsx_xflags = btrfs_inode_flags_to_xflags(binode->flags);
380 if (copy_to_user(arg, &fa, sizeof(fa)))
381 return -EFAULT;
383 return 0;
384 }
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;
397 if (!inode_owner_or_capable(inode))
398 return -EPERM;
400 if (btrfs_root_readonly(root))
401 return -EROFS;
403 memset(&fa, 0, sizeof(fa));
404 if (copy_from_user(&fa, arg, sizeof(fa)))
405 return -EFAULT;
407 ret = check_xflags(fa.fsx_xflags);
408 if (ret)
409 return ret;
411 if (fa.fsx_extsize != 0 || fa.fsx_projid != 0 || fa.fsx_cowextsize != 0)
412 return -EOPNOTSUPP;
414 ret = mnt_want_write_file(file);
415 if (ret)
416 return ret;
418 inode_lock(inode);
420 old_flags = binode->flags;
421 old_i_flags = inode->i_flags;
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 }
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;
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 }
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);
464 btrfs_end_transaction(trans);
466 out_unlock:
467 if (ret) {
468 binode->flags = old_flags;
469 inode->i_flags = old_i_flags;
470 }
472 inode_unlock(inode);
473 mnt_drop_write_file(file);
475 return ret;
476 }
478 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
479 {
480 struct inode *inode = file_inode(file);
482 return put_user(inode->i_generation, arg);
483 }
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;
497 if (!capable(CAP_SYS_ADMIN))
498 return -EPERM;
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();
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;
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;
528 if (copy_to_user(arg, &range, sizeof(range)))
529 return -EFAULT;
531 return 0;
532 }
534 int btrfs_is_empty_uuid(u8 *uuid)
535 {
536 int i;
538 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
539 if (uuid[i])
540 return 0;
541 }
542 return 1;
543 }
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;
569 root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
570 if (!root_item)
571 return -ENOMEM;
573 ret = btrfs_find_free_objectid(fs_info->tree_root, &objectid);
574 if (ret)
575 goto fail_free;
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 }
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;
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;
604 ret = btrfs_qgroup_inherit(trans, 0, objectid, inherit);
605 if (ret)
606 goto fail;
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 }
614 btrfs_mark_buffer_dirty(leaf);
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);
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);
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);
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);
645 btrfs_tree_unlock(leaf);
646 free_extent_buffer(leaf);
647 leaf = NULL;
649 btrfs_set_root_dirid(root_item, new_dirid);
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;
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 }
667 btrfs_record_root_in_trans(trans, new_root);
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 }
676 mutex_lock(&new_root->objectid_mutex);
677 new_root->highest_objectid = new_dirid;
678 mutex_unlock(&new_root->objectid_mutex);
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 }
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 }
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);
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);
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);
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);
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;
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;
735 fail_free:
736 kfree(root_item);
737 return ret;
738 }
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;
752 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
753 return -EINVAL;
755 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL);
756 if (!pending_snapshot)
757 return -ENOMEM;
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 }
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);
778 ret = btrfs_start_delalloc_inodes(root);
779 if (ret)
780 goto dec_and_free;
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;
790 btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
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;
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;
814 trans = btrfs_start_transaction(root, 0);
815 if (IS_ERR(trans)) {
816 ret = PTR_ERR(trans);
817 goto fail;
818 }
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;
835 ret = pending_snapshot->error;
836 if (ret)
837 goto fail;
839 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
840 if (ret)
841 goto fail;
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 }
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);
863 return ret;
864 }
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 */
886 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
887 {
888 int error;
890 if (d_really_is_negative(victim))
891 return -ENOENT;
893 BUG_ON(d_inode(victim->d_parent) != dir);
894 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
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 }
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 }
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;
944 error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
945 if (error == -EINTR)
946 return error;
948 dentry = lookup_one_len(name, parent->dentry, namelen);
949 error = PTR_ERR(dentry);
950 if (IS_ERR(dentry))
951 goto out_unlock;
953 error = btrfs_may_create(dir, dentry);
954 if (error)
955 goto out_dput;
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;
967 down_read(&fs_info->subvol_sem);
969 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
970 goto out_up_read;
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 }
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;
1004 read_lock(&em_tree->lock);
1005 em = lookup_extent_mapping(em_tree, offset, PAGE_SIZE);
1006 read_unlock(&em_tree->lock);
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 }
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));
1042 path = btrfs_alloc_path();
1043 if (!path)
1044 return -ENOMEM;
1046 min_key.objectid = ino;
1047 min_key.type = BTRFS_EXTENT_DATA_KEY;
1048 min_key.offset = *off;
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;
1060 leaf = path->nodes[0];
1061 extent = btrfs_item_ptr(leaf, path->slots[0],
1062 struct btrfs_file_extent_item);
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 }
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 }
1079 if (min_key.offset == (u64)-1)
1080 goto none;
1082 min_key.offset++;
1083 btrfs_release_path(path);
1084 }
1085 none:
1086 btrfs_free_path(path);
1087 return -ENOENT;
1088 }
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;
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);
1105 if (!em) {
1106 struct extent_state *cached = NULL;
1107 u64 end = start + len - 1;
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);
1114 if (IS_ERR(em))
1115 return NULL;
1116 }
1118 return em;
1119 }
1121 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1122 {
1123 struct extent_map *next;
1124 bool ret = true;
1126 /* this is the last extent */
1127 if (em->start + em->len >= i_size_read(inode))
1128 return false;
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;
1137 free_extent_map(next);
1138 return ret;
1139 }
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;
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;
1157 *skip = 0;
1159 em = defrag_lookup_extent(inode, start);
1160 if (!em)
1161 return 0;
1163 /* this will cover holes, and inline extents */
1164 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1165 ret = 0;
1166 goto out;
1167 }
1169 if (!*defrag_end)
1170 prev_mergeable = false;
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 }
1197 free_extent_map(em);
1198 return ret;
1199 }
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);
1232 file_end = (isize - 1) >> PAGE_SHIFT;
1233 if (!isize || start_index > file_end)
1234 return 0;
1236 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
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;
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;
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;
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 }
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 }
1293 if (page->mapping != inode->i_mapping) {
1294 unlock_page(page);
1295 put_page(page);
1296 goto again;
1297 }
1299 pages[i] = page;
1300 i_done++;
1301 }
1302 if (!i_done || ret)
1303 goto out;
1305 if (!(inode->i_sb->s_flags & SB_ACTIVE))
1306 goto out;
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]);
1315 page_start = page_offset(pages[0]);
1316 page_end = page_offset(pages[i_done - 1]) + PAGE_SIZE;
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);
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 }
1335 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1336 &cached_state);
1338 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1339 page_start, page_end - 1, &cached_state);
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;
1366 }
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;
1393 if (isize == 0)
1394 return 0;
1396 if (range->start >= isize)
1397 return -EINVAL;
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 }
1406 if (extent_thresh == 0)
1407 extent_thresh = SZ_256K;
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 }
1422 pages = kmalloc_array(max_cluster, sizeof(struct page *), GFP_KERNEL);
1423 if (!pages) {
1424 ret = -ENOMEM;
1425 goto out_ra;
1426 }
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 }
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;
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;
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;
1470 if (btrfs_defrag_cancelled(fs_info)) {
1471 btrfs_debug(fs_info, "defrag_file cancelled");
1472 ret = -EAGAIN;
1473 break;
1474 }
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 }
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 }
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 }
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 }
1514 defrag_count += ret;
1515 balance_dirty_pages_ratelimited(inode->i_mapping);
1516 inode_unlock(inode);
1518 if (newer_than) {
1519 if (newer_off == (u64)-1)
1520 break;
1522 if (ret > 0)
1523 i += ret;
1525 newer_off = max(newer_off + 1,
1526 (u64)i << PAGE_SHIFT);
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 }
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 }
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 }
1560 ret = defrag_count;
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 }
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;
1592 if (!capable(CAP_SYS_ADMIN))
1593 return -EPERM;
1595 ret = mnt_want_write_file(file);
1596 if (ret)
1597 return ret;
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 }
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 }
1610 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
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 }
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 }
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 }
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 }
1661 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
1662 ret = -EPERM;
1663 goto out_free;
1664 }
1666 old_size = btrfs_device_get_total_bytes(device);
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 }
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 }
1691 new_size = round_down(new_size, fs_info->sectorsize);
1693 btrfs_info_in_rcu(fs_info, "new size for %s is %llu",
1694 rcu_str_deref(device->name), new_size);
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 */
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 }
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;
1724 if (!S_ISDIR(file_inode(file)->i_mode))
1725 return -ENOTDIR;
1727 ret = mnt_want_write_file(file);
1728 if (ret)
1729 goto out;
1731 namelen = strlen(name);
1732 if (strchr(name, '/')) {
1733 ret = -EINVAL;
1734 goto out_drop_write;
1735 }
1737 if (name[0] == '.' &&
1738 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1739 ret = -EEXIST;
1740 goto out_drop_write;
1741 }
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 }
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 }
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;
1784 if (!S_ISDIR(file_inode(file)->i_mode))
1785 return -ENOTDIR;
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';
1792 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1793 vol_args->fd, subvol,
1794 NULL, false, NULL);
1796 kfree(vol_args);
1797 return ret;
1798 }
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;
1810 if (!S_ISDIR(file_inode(file)->i_mode))
1811 return -ENOTDIR;
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';
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 }
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 }
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;
1847 if (ptr && copy_to_user(arg +
1848 offsetof(struct btrfs_ioctl_vol_args_v2,
1849 transid),
1850 ptr, sizeof(*ptr)))
1851 ret = -EFAULT;
1853 free_inherit:
1854 kfree(inherit);
1855 free_args:
1856 kfree(vol_args);
1857 return ret;
1858 }
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;
1869 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)
1870 return -EINVAL;
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);
1877 if (copy_to_user(arg, &flags, sizeof(flags)))
1878 ret = -EFAULT;
1880 return ret;
1881 }
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;
1894 if (!inode_owner_or_capable(inode))
1895 return -EPERM;
1897 ret = mnt_want_write_file(file);
1898 if (ret)
1899 goto out;
1901 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
1902 ret = -EINVAL;
1903 goto out_drop_write;
1904 }
1906 if (copy_from_user(&flags, arg, sizeof(flags))) {
1907 ret = -EFAULT;
1908 goto out_drop_write;
1909 }
1911 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1912 ret = -EINVAL;
1913 goto out_drop_write;
1914 }
1916 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1917 ret = -EOPNOTSUPP;
1918 goto out_drop_write;
1919 }
1921 down_write(&fs_info->subvol_sem);
1923 /* nothing to do */
1924 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1925 goto out_drop_sem;
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 }
1951 trans = btrfs_start_transaction(root, 1);
1952 if (IS_ERR(trans)) {
1953 ret = PTR_ERR(trans);
1954 goto out_reset;
1955 }
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 }
1964 ret = btrfs_commit_transaction(trans);
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 }
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;
1983 test.objectid = sk->min_objectid;
1984 test.type = sk->min_type;
1985 test.offset = sk->min_offset;
1987 ret = btrfs_comp_cpu_keys(key, &test);
1988 if (ret < 0)
1989 return 0;
1991 test.objectid = sk->max_objectid;
1992 test.type = sk->max_type;
1993 test.offset = sk->max_offset;
1995 ret = btrfs_comp_cpu_keys(key, &test);
1996 if (ret > 0)
1997 return 0;
1998 return 1;
1999 }
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;
2020 leaf = path->nodes[0];
2021 slot = path->slots[0];
2022 nritems = btrfs_header_nritems(leaf);
2024 if (btrfs_header_generation(leaf) > sk->max_transid) {
2025 i = nritems;
2026 goto advance_key;
2027 }
2028 found_transid = btrfs_header_generation(leaf);
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);
2034 btrfs_item_key_to_cpu(leaf, key, i);
2035 if (!key_in_sk(key, sk))
2036 continue;
2038 if (sizeof(sh) + item_len > *buf_size) {
2039 if (*num_found) {
2040 ret = 1;
2041 goto out;
2042 }
2044 /*
2045 * return one empty item back for v1, which does not
2046 * handle -EOVERFLOW
2047 */
2049 *buf_size = sizeof(sh) + item_len;
2050 item_len = 0;
2051 ret = -EOVERFLOW;
2052 }
2054 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2055 ret = 1;
2056 goto out;
2057 }
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;
2065 /* copy search result header */
2066 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
2067 ret = -EFAULT;
2068 goto out;
2069 }
2071 *sk_offset += sizeof(sh);
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 }
2082 *sk_offset += item_len;
2083 }
2084 (*num_found)++;
2086 if (ret) /* -EOVERFLOW from above */
2087 goto out;
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 }
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;
2138 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2139 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2140 return -EOVERFLOW;
2141 }
2143 path = btrfs_alloc_path();
2144 if (!path)
2145 return -ENOMEM;
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 }
2161 key.objectid = sk->min_objectid;
2162 key.type = sk->min_type;
2163 key.offset = sk->min_offset;
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;
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 }
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;
2196 if (!capable(CAP_SYS_ADMIN))
2197 return -EPERM;
2199 uargs = (struct btrfs_ioctl_search_args __user *)argp;
2201 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2202 return -EFAULT;
2204 buf_size = sizeof(uargs->buf);
2206 inode = file_inode(file);
2207 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
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;
2216 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2217 ret = -EFAULT;
2218 return ret;
2219 }
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;
2231 if (!capable(CAP_SYS_ADMIN))
2232 return -EPERM;
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;
2239 buf_size = args.buf_size;
2241 /* limit result size to 16MB */
2242 if (buf_size > buf_limit)
2243 buf_size = buf_limit;
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;
2254 return ret;
2255 }
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;
2275 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2276 name[0]='\0';
2277 return 0;
2278 }
2280 path = btrfs_alloc_path();
2281 if (!path)
2282 return -ENOMEM;
2284 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1];
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 }
2295 key.objectid = dirid;
2296 key.type = BTRFS_INODE_REF_KEY;
2297 key.offset = (u64)-1;
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 }
2314 l = path->nodes[0];
2315 slot = path->slots[0];
2316 btrfs_item_key_to_cpu(l, &key, slot);
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 }
2327 *(ptr + len) = '/';
2328 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2330 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2331 break;
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 }
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;
2369 path = btrfs_alloc_path();
2370 if (!path)
2371 return -ENOMEM;
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];
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 }
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 }
2407 leaf = path->nodes[0];
2408 slot = path->slots[0];
2409 btrfs_item_key_to_cpu(leaf, &key, slot);
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 }
2420 *(ptr + len) = '/';
2421 read_extent_buffer(leaf, ptr,
2422 (unsigned long)(iref + 1), len);
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 }
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 }
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 }
2454 if (key.offset == upper_limit.objectid)
2455 break;
2456 if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {
2457 ret = -EACCES;
2458 goto out;
2459 }
2461 btrfs_release_path(path);
2462 key.objectid = key.offset;
2463 key.offset = (u64)-1;
2464 dirid = key.objectid;
2465 }
2467 memmove(args->path, ptr, total_len);
2468 args->path[total_len] = '\0';
2469 btrfs_release_path(path);
2470 }
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 }
2485 leaf = path->nodes[0];
2486 slot = path->slots[0];
2487 btrfs_item_key_to_cpu(leaf, &key, slot);
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 }
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;
2504 out:
2505 btrfs_free_path(path);
2506 return ret;
2507 }
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;
2516 args = memdup_user(argp, sizeof(*args));
2517 if (IS_ERR(args))
2518 return PTR_ERR(args);
2520 inode = file_inode(file);
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;
2529 if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2530 args->name[0] = 0;
2531 goto out;
2532 }
2534 if (!capable(CAP_SYS_ADMIN)) {
2535 ret = -EPERM;
2536 goto out;
2537 }
2539 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2540 args->treeid, args->objectid,
2541 args->name);
2543 out:
2544 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2545 ret = -EFAULT;
2547 kfree(args);
2548 return ret;
2549 }
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;
2569 args = memdup_user(argp, sizeof(*args));
2570 if (IS_ERR(args))
2571 return PTR_ERR(args);
2573 inode = file_inode(file);
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 }
2585 ret = btrfs_search_path_in_tree_user(inode, args);
2587 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2588 ret = -EFAULT;
2590 kfree(args);
2591 return ret;
2592 }
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;
2611 path = btrfs_alloc_path();
2612 if (!path)
2613 return -ENOMEM;
2615 subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL);
2616 if (!subvol_info) {
2617 btrfs_free_path(path);
2618 return -ENOMEM;
2619 }
2621 inode = file_inode(file);
2622 fs_info = BTRFS_I(inode)->root->fs_info;
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;
2635 subvol_info->treeid = key.objectid;
2637 subvol_info->generation = btrfs_root_generation(root_item);
2638 subvol_info->flags = btrfs_root_flags(root_item);
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);
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);
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);
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);
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);
2662 if (key.objectid != BTRFS_FS_TREE_OBJECTID) {
2663 /* Search root tree for ROOT_BACKREF of this subvolume */
2664 root = fs_info->tree_root;
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 }
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;
2689 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2690 subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref);
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 }
2704 if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))
2705 ret = -EFAULT;
2707 out:
2708 btrfs_free_path(path);
2709 kzfree(subvol_info);
2710 return ret;
2711 }
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;
2731 path = btrfs_alloc_path();
2732 if (!path)
2733 return -ENOMEM;
2735 rootrefs = memdup_user(argp, sizeof(*rootrefs));
2736 if (IS_ERR(rootrefs)) {
2737 btrfs_free_path(path);
2738 return PTR_ERR(rootrefs);
2739 }
2741 inode = file_inode(file);
2742 root = BTRFS_I(inode)->root->fs_info->tree_root;
2743 objectid = BTRFS_I(inode)->root->root_key.objectid;
2745 key.objectid = objectid;
2746 key.type = BTRFS_ROOT_REF_KEY;
2747 key.offset = rootrefs->min_treeid;
2748 found = 0;
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];
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 }
2773 if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) {
2774 ret = -EOVERFLOW;
2775 goto out;
2776 }
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++;
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 }
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 }
2804 kfree(rootrefs);
2805 btrfs_free_path(path);
2807 return ret;
2808 }
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;
2824 if (!S_ISDIR(dir->i_mode))
2825 return -ENOTDIR;
2827 vol_args = memdup_user(arg, sizeof(*vol_args));
2828 if (IS_ERR(vol_args))
2829 return PTR_ERR(vol_args);
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 }
2839 err = mnt_want_write_file(file);
2840 if (err)
2841 goto out;
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 }
2853 if (d_really_is_negative(dentry)) {
2854 err = -ENOENT;
2855 goto out_dput;
2856 }
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;
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;
2889 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2890 if (err)
2891 goto out_dput;
2892 }
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;
2899 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
2900 err = -EINVAL;
2901 goto out_dput;
2902 }
2904 inode_lock(inode);
2905 err = btrfs_delete_subvolume(dir, dentry);
2906 inode_unlock(inode);
2907 if (!err)
2908 d_delete(dentry);
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 }
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;
2928 ret = mnt_want_write_file(file);
2929 if (ret)
2930 return ret;
2932 if (btrfs_root_readonly(root)) {
2933 ret = -EROFS;
2934 goto out;
2935 }
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 }
2957 range = kzalloc(sizeof(*range), GFP_KERNEL);
2958 if (!range) {
2959 ret = -ENOMEM;
2960 goto out;
2961 }
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 }
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;
2998 if (!capable(CAP_SYS_ADMIN))
2999 return -EPERM;
3001 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags))
3002 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
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 }
3010 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3011 ret = btrfs_init_new_device(fs_info, vol_args->name);
3013 if (!ret)
3014 btrfs_info(fs_info, "disk added %s", vol_args->name);
3016 kfree(vol_args);
3017 out:
3018 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3019 return ret;
3020 }
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;
3029 if (!capable(CAP_SYS_ADMIN))
3030 return -EPERM;
3032 ret = mnt_want_write_file(file);
3033 if (ret)
3034 return ret;
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 }
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 }
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 }
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);
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 }
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;
3083 if (!capable(CAP_SYS_ADMIN))
3084 return -EPERM;
3086 ret = mnt_want_write_file(file);
3087 if (ret)
3088 return ret;
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 }
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 }
3101 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3102 ret = btrfs_rm_device(fs_info, vol_args->name, 0);
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);
3112 return ret;
3113 }
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;
3123 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
3124 if (!fi_args)
3125 return -ENOMEM;
3127 rcu_read_lock();
3128 fi_args->num_devices = fs_devices->num_devices;
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();
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;
3141 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
3142 ret = -EFAULT;
3144 kfree(fi_args);
3145 return ret;
3146 }
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;
3156 di_args = memdup_user(arg, sizeof(*di_args));
3157 if (IS_ERR(di_args))
3158 return PTR_ERR(di_args);
3160 if (!btrfs_is_empty_uuid(di_args->uuid))
3161 s_uuid = di_args->uuid;
3163 rcu_read_lock();
3164 dev = btrfs_find_device(fs_info, di_args->devid, s_uuid, NULL);
3166 if (!dev) {
3167 ret = -ENODEV;
3168 goto out;
3169 }
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 }
3183 out:
3184 rcu_read_unlock();
3185 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
3186 ret = -EFAULT;
3188 kfree(di_args);
3189 return ret;
3190 }
3192 static struct page *extent_same_get_page(struct inode *inode, pgoff_t index)
3193 {
3194 struct page *page;
3196 page = grab_cache_page(inode->i_mapping, index);
3197 if (!page)
3198 return ERR_PTR(-ENOMEM);
3200 if (!PageUptodate(page)) {
3201 int ret;
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 }
3219 return page;
3220 }
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;
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]);
3234 if (err == -EAGAIN)
3235 goto again;
3236 pages[i] = NULL;
3237 return err;
3238 }
3239 }
3240 return 0;
3241 }
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 }
3278 static void btrfs_double_inode_unlock(struct inode *inode1, struct inode *inode2)
3279 {
3280 inode_unlock(inode1);
3281 inode_unlock(inode2);
3282 }
3284 static void btrfs_double_inode_lock(struct inode *inode1, struct inode *inode2)
3285 {
3286 if (inode1 < inode2)
3287 swap(inode1, inode2);
3289 inode_lock_nested(inode1, I_MUTEX_PARENT);
3290 inode_lock_nested(inode2, I_MUTEX_CHILD);
3291 }
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 }
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;
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 }
3320 struct cmp_pages {
3321 int num_pages;
3322 struct page **src_pages;
3323 struct page **dst_pages;
3324 };
3326 static void btrfs_cmp_data_free(struct cmp_pages *cmp)
3327 {
3328 int i;
3329 struct page *pg;
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 }
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;
3354 cmp->num_pages = num_pages;
3356 ret = gather_extent_pages(src, cmp->src_pages, num_pages, loff);
3357 if (ret)
3358 goto out;
3360 ret = gather_extent_pages(dst, cmp->dst_pages, num_pages, dst_loff);
3362 out:
3363 if (ret)
3364 btrfs_cmp_data_free(cmp);
3365 return ret;
3366 }
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;
3376 i = 0;
3377 while (len) {
3378 if (len < PAGE_SIZE)
3379 cmp_len = len;
3381 BUG_ON(i >= cmp->num_pages);
3383 src_page = cmp->src_pages[i];
3384 dst_page = cmp->dst_pages[i];
3385 ASSERT(PageLocked(src_page));
3386 ASSERT(PageLocked(dst_page));
3388 addr = kmap_atomic(src_page);
3389 dst_addr = kmap_atomic(dst_page);
3391 flush_dcache_page(src_page);
3392 flush_dcache_page(dst_page);
3394 if (memcmp(addr, dst_addr, cmp_len))
3395 ret = -EBADE;
3397 kunmap_atomic(addr);
3398 kunmap_atomic(dst_addr);
3400 if (ret)
3401 break;
3403 len -= cmp_len;
3404 i++;
3405 }
3407 return ret;
3408 }
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;
3416 if (off + olen > inode->i_size || off + olen < off)
3417 return -EINVAL;
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;
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;
3427 return 0;
3428 }
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;
3440 ret = extent_same_check_offsets(src, loff, &len, olen);
3441 if (ret)
3442 return ret;
3444 ret = extent_same_check_offsets(dst, dst_loff, &len, olen);
3445 if (ret)
3446 return ret;
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;
3466 /* Check for overlapping ranges */
3467 if (dst_loff + len > loff && dst_loff < loff + len)
3468 return -EINVAL;
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;
3488 len = round_down(i_size_read(src), sz) - loff;
3489 olen = len;
3490 }
3491 }
3493 again:
3494 ret = btrfs_cmp_data_prepare(src, loff, dst, dst_loff, olen, cmp);
3495 if (ret)
3496 return ret;
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 }
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);
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);
3545 btrfs_cmp_data_free(cmp);
3547 return ret;
3548 }
3550 #define BTRFS_MAX_DEDUPE_LEN SZ_16M
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;
3561 if (olen == 0)
3562 return 0;
3564 if (same_inode)
3565 inode_lock(src);
3566 else
3567 btrfs_double_inode_lock(src, dst);
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 }
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;
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);
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 }
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;
3609 loff += BTRFS_MAX_DEDUPE_LEN;
3610 dst_loff += BTRFS_MAX_DEDUPE_LEN;
3611 }
3613 if (tail_len > 0)
3614 ret = btrfs_extent_same_range(src, loff, tail_len, dst,
3615 dst_loff, &cmp);
3617 out_free:
3618 kvfree(cmp.src_pages);
3619 kvfree(cmp.dst_pages);
3621 out_unlock:
3622 if (same_inode)
3623 inode_unlock(src);
3624 else
3625 btrfs_double_inode_unlock(src, dst);
3627 return ret;
3628 }
3630 int btrfs_dedupe_file_range(struct file *src_file, loff_t src_loff,
3631 struct file *dst_file, loff_t dst_loff,
3632 u64 olen)
3633 {
3634 struct inode *src = file_inode(src_file);
3635 struct inode *dst = file_inode(dst_file);
3636 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
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 }
3647 return btrfs_extent_same(src, src_loff, olen, dst, dst_loff);
3648 }
3650 static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3651 struct inode *inode,
3652 u64 endoff,
3653 const u64 destoff,
3654 const u64 olen,
3655 int no_time_update)
3656 {
3657 struct btrfs_root *root = BTRFS_I(inode)->root;
3658 int ret;
3660 inode_inc_iversion(inode);
3661 if (!no_time_update)
3662 inode->i_mtime = inode->i_ctime = current_time(inode);
3663 /*
3664 * We round up to the block size at eof when determining which
3665 * extents to clone above, but shouldn't round up the file size.
3666 */
3667 if (endoff > destoff + olen)
3668 endoff = destoff + olen;
3669 if (endoff > inode->i_size)
3670 btrfs_i_size_write(BTRFS_I(inode), endoff);
3672 ret = btrfs_update_inode(trans, root, inode);
3673 if (ret) {
3674 btrfs_abort_transaction(trans, ret);
3675 btrfs_end_transaction(trans);
3676 goto out;
3677 }
3678 ret = btrfs_end_transaction(trans);
3679 out:
3680 return ret;
3681 }
3683 static void clone_update_extent_map(struct btrfs_inode *inode,
3684 const struct btrfs_trans_handle *trans,
3685 const struct btrfs_path *path,
3686 const u64 hole_offset,
3687 const u64 hole_len)
3688 {
3689 struct extent_map_tree *em_tree = &inode->extent_tree;
3690 struct extent_map *em;
3691 int ret;
3693 em = alloc_extent_map();
3694 if (!em) {
3695 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags);
3696 return;
3697 }
3699 if (path) {
3700 struct btrfs_file_extent_item *fi;
3702 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
3703 struct btrfs_file_extent_item);
3704 btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
3705 em->generation = -1;
3706 if (btrfs_file_extent_type(path->nodes[0], fi) ==
3707 BTRFS_FILE_EXTENT_INLINE)
3708 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3709 &inode->runtime_flags);
3710 } else {
3711 em->start = hole_offset;
3712 em->len = hole_len;
3713 em->ram_bytes = em->len;
3714 em->orig_start = hole_offset;
3715 em->block_start = EXTENT_MAP_HOLE;
3716 em->block_len = 0;
3717 em->orig_block_len = 0;
3718 em->compress_type = BTRFS_COMPRESS_NONE;
3719 em->generation = trans->transid;
3720 }
3722 while (1) {
3723 write_lock(&em_tree->lock);
3724 ret = add_extent_mapping(em_tree, em, 1);
3725 write_unlock(&em_tree->lock);
3726 if (ret != -EEXIST) {
3727 free_extent_map(em);
3728 break;
3729 }
3730 btrfs_drop_extent_cache(inode, em->start,
3731 em->start + em->len - 1, 0);
3732 }
3734 if (ret)
3735 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags);
3736 }
3738 /*
3739 * Make sure we do not end up inserting an inline extent into a file that has
3740 * already other (non-inline) extents. If a file has an inline extent it can
3741 * not have any other extents and the (single) inline extent must start at the
3742 * file offset 0. Failing to respect these rules will lead to file corruption,
3743 * resulting in EIO errors on read/write operations, hitting BUG_ON's in mm, etc
3744 *
3745 * We can have extents that have been already written to disk or we can have
3746 * dirty ranges still in delalloc, in which case the extent maps and items are
3747 * created only when we run delalloc, and the delalloc ranges might fall outside
3748 * the range we are currently locking in the inode's io tree. So we check the
3749 * inode's i_size because of that (i_size updates are done while holding the
3750 * i_mutex, which we are holding here).
3751 * We also check to see if the inode has a size not greater than "datal" but has
3752 * extents beyond it, due to an fallocate with FALLOC_FL_KEEP_SIZE (and we are
3753 * protected against such concurrent fallocate calls by the i_mutex).
3754 *
3755 * If the file has no extents but a size greater than datal, do not allow the
3756 * copy because we would need turn the inline extent into a non-inline one (even
3757 * with NO_HOLES enabled). If we find our destination inode only has one inline
3758 * extent, just overwrite it with the source inline extent if its size is less
3759 * than the source extent's size, or we could copy the source inline extent's
3760 * data into the destination inode's inline extent if the later is greater then
3761 * the former.
3762 */
3763 static int clone_copy_inline_extent(struct inode *dst,
3764 struct btrfs_trans_handle *trans,
3765 struct btrfs_path *path,
3766 struct btrfs_key *new_key,
3767 const u64 drop_start,
3768 const u64 datal,
3769 const u64 skip,
3770 const u64 size,
3771 char *inline_data)
3772 {
3773 struct btrfs_fs_info *fs_info = btrfs_sb(dst->i_sb);
3774 struct btrfs_root *root = BTRFS_I(dst)->root;
3775 const u64 aligned_end = ALIGN(new_key->offset + datal,
3776 fs_info->sectorsize);
3777 int ret;
3778 struct btrfs_key key;
3780 if (new_key->offset > 0)
3781 return -EOPNOTSUPP;
3783 key.objectid = btrfs_ino(BTRFS_I(dst));
3784 key.type = BTRFS_EXTENT_DATA_KEY;
3785 key.offset = 0;
3786 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3787 if (ret < 0) {
3788 return ret;
3789 } else if (ret > 0) {
3790 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
3791 ret = btrfs_next_leaf(root, path);
3792 if (ret < 0)
3793 return ret;
3794 else if (ret > 0)
3795 goto copy_inline_extent;
3796 }
3797 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
3798 if (key.objectid == btrfs_ino(BTRFS_I(dst)) &&
3799 key.type == BTRFS_EXTENT_DATA_KEY) {
3800 ASSERT(key.offset > 0);
3801 return -EOPNOTSUPP;
3802 }
3803 } else if (i_size_read(dst) <= datal) {
3804 struct btrfs_file_extent_item *ei;
3805 u64 ext_len;
3807 /*
3808 * If the file size is <= datal, make sure there are no other
3809 * extents following (can happen do to an fallocate call with
3810 * the flag FALLOC_FL_KEEP_SIZE).
3811 */
3812 ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
3813 struct btrfs_file_extent_item);
3814 /*
3815 * If it's an inline extent, it can not have other extents
3816 * following it.
3817 */
3818 if (btrfs_file_extent_type(path->nodes[0], ei) ==
3819 BTRFS_FILE_EXTENT_INLINE)
3820 goto copy_inline_extent;
3822 ext_len = btrfs_file_extent_num_bytes(path->nodes[0], ei);
3823 if (ext_len > aligned_end)
3824 return -EOPNOTSUPP;
3826 ret = btrfs_next_item(root, path);
3827 if (ret < 0) {
3828 return ret;
3829 } else if (ret == 0) {
3830 btrfs_item_key_to_cpu(path->nodes[0], &key,
3831 path->slots[0]);
3832 if (key.objectid == btrfs_ino(BTRFS_I(dst)) &&
3833 key.type == BTRFS_EXTENT_DATA_KEY)
3834 return -EOPNOTSUPP;
3835 }
3836 }
3838 copy_inline_extent:
3839 /*
3840 * We have no extent items, or we have an extent at offset 0 which may
3841 * or may not be inlined. All these cases are dealt the same way.
3842 */
3843 if (i_size_read(dst) > datal) {
3844 /*
3845 * If the destination inode has an inline extent...
3846 * This would require copying the data from the source inline
3847 * extent into the beginning of the destination's inline extent.
3848 * But this is really complex, both extents can be compressed
3849 * or just one of them, which would require decompressing and
3850 * re-compressing data (which could increase the new compressed
3851 * size, not allowing the compressed data to fit anymore in an
3852 * inline extent).
3853 * So just don't support this case for now (it should be rare,
3854 * we are not really saving space when cloning inline extents).
3855 */
3856 return -EOPNOTSUPP;
3857 }
3859 btrfs_release_path(path);
3860 ret = btrfs_drop_extents(trans, root, dst, drop_start, aligned_end, 1);
3861 if (ret)
3862 return ret;
3863 ret = btrfs_insert_empty_item(trans, root, path, new_key, size);
3864 if (ret)
3865 return ret;
3867 if (skip) {
3868 const u32 start = btrfs_file_extent_calc_inline_size(0);
3870 memmove(inline_data + start, inline_data + start + skip, datal);
3871 }
3873 write_extent_buffer(path->nodes[0], inline_data,
3874 btrfs_item_ptr_offset(path->nodes[0],
3875 path->slots[0]),
3876 size);
3877 inode_add_bytes(dst, datal);
3879 return 0;
3880 }
3882 /**
3883 * btrfs_clone() - clone a range from inode file to another
3884 *
3885 * @src: Inode to clone from
3886 * @inode: Inode to clone to
3887 * @off: Offset within source to start clone from
3888 * @olen: Original length, passed by user, of range to clone
3889 * @olen_aligned: Block-aligned value of olen
3890 * @destoff: Offset within @inode to start clone
3891 * @no_time_update: Whether to update mtime/ctime on the target inode
3892 */
3893 static int btrfs_clone(struct inode *src, struct inode *inode,
3894 const u64 off, const u64 olen, const u64 olen_aligned,
3895 const u64 destoff, int no_time_update)
3896 {
3897 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3898 struct btrfs_root *root = BTRFS_I(inode)->root;
3899 struct btrfs_path *path = NULL;
3900 struct extent_buffer *leaf;
3901 struct btrfs_trans_handle *trans;
3902 char *buf = NULL;
3903 struct btrfs_key key;
3904 u32 nritems;
3905 int slot;
3906 int ret;
3907 const u64 len = olen_aligned;
3908 u64 last_dest_end = destoff;
3910 ret = -ENOMEM;
3911 buf = kvmalloc(fs_info->nodesize, GFP_KERNEL);
3912 if (!buf)
3913 return ret;
3915 path = btrfs_alloc_path();
3916 if (!path) {
3917 kvfree(buf);
3918 return ret;
3919 }
3921 path->reada = READA_FORWARD;
3922 /* clone data */
3923 key.objectid = btrfs_ino(BTRFS_I(src));
3924 key.type = BTRFS_EXTENT_DATA_KEY;
3925 key.offset = off;
3927 while (1) {
3928 u64 next_key_min_offset = key.offset + 1;
3930 /*
3931 * note the key will change type as we walk through the
3932 * tree.
3933 */
3934 path->leave_spinning = 1;
3935 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3936 0, 0);
3937 if (ret < 0)
3938 goto out;
3939 /*
3940 * First search, if no extent item that starts at offset off was
3941 * found but the previous item is an extent item, it's possible
3942 * it might overlap our target range, therefore process it.
3943 */
3944 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3945 btrfs_item_key_to_cpu(path->nodes[0], &key,
3946 path->slots[0] - 1);
3947 if (key.type == BTRFS_EXTENT_DATA_KEY)
3948 path->slots[0]--;
3949 }
3951 nritems = btrfs_header_nritems(path->nodes[0]);
3952 process_slot:
3953 if (path->slots[0] >= nritems) {
3954 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3955 if (ret < 0)
3956 goto out;
3957 if (ret > 0)
3958 break;
3959 nritems = btrfs_header_nritems(path->nodes[0]);
3960 }
3961 leaf = path->nodes[0];
3962 slot = path->slots[0];
3964 btrfs_item_key_to_cpu(leaf, &key, slot);
3965 if (key.type > BTRFS_EXTENT_DATA_KEY ||
3966 key.objectid != btrfs_ino(BTRFS_I(src)))
3967 break;
3969 if (key.type == BTRFS_EXTENT_DATA_KEY) {
3970 struct btrfs_file_extent_item *extent;
3971 int type;
3972 u32 size;
3973 struct btrfs_key new_key;
3974 u64 disko = 0, diskl = 0;
3975 u64 datao = 0, datal = 0;
3976 u8 comp;
3977 u64 drop_start;
3979 extent = btrfs_item_ptr(leaf, slot,
3980 struct btrfs_file_extent_item);
3981 comp = btrfs_file_extent_compression(leaf, extent);
3982 type = btrfs_file_extent_type(leaf, extent);
3983 if (type == BTRFS_FILE_EXTENT_REG ||
3984 type == BTRFS_FILE_EXTENT_PREALLOC) {
3985 disko = btrfs_file_extent_disk_bytenr(leaf,
3986 extent);
3987 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3988 extent);
3989 datao = btrfs_file_extent_offset(leaf, extent);
3990 datal = btrfs_file_extent_num_bytes(leaf,
3991 extent);
3992 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3993 /* take upper bound, may be compressed */
3994 datal = btrfs_file_extent_ram_bytes(leaf,
3995 extent);
3996 }
3998 /*
3999 * The first search might have left us at an extent
4000 * item that ends before our target range's start, can
4001 * happen if we have holes and NO_HOLES feature enabled.
4002 */
4003 if (key.offset + datal <= off) {
4004 path->slots[0]++;
4005 goto process_slot;
4006 } else if (key.offset >= off + len) {
4007 break;
4008 }
4009 next_key_min_offset = key.offset + datal;
4010 size = btrfs_item_size_nr(leaf, slot);
4011 read_extent_buffer(leaf, buf,
4012 btrfs_item_ptr_offset(leaf, slot),
4013 size);
4015 btrfs_release_path(path);
4016 path->leave_spinning = 0;
4018 memcpy(&new_key, &key, sizeof(new_key));
4019 new_key.objectid = btrfs_ino(BTRFS_I(inode));
4020 if (off <= key.offset)
4021 new_key.offset = key.offset + destoff - off;
4022 else
4023 new_key.offset = destoff;
4025 /*
4026 * Deal with a hole that doesn't have an extent item
4027 * that represents it (NO_HOLES feature enabled).
4028 * This hole is either in the middle of the cloning
4029 * range or at the beginning (fully overlaps it or
4030 * partially overlaps it).
4031 */
4032 if (new_key.offset != last_dest_end)
4033 drop_start = last_dest_end;
4034 else
4035 drop_start = new_key.offset;
4037 /*
4038 * 1 - adjusting old extent (we may have to split it)
4039 * 1 - add new extent
4040 * 1 - inode update
4041 */
4042 trans = btrfs_start_transaction(root, 3);
4043 if (IS_ERR(trans)) {
4044 ret = PTR_ERR(trans);
4045 goto out;
4046 }
4048 if (type == BTRFS_FILE_EXTENT_REG ||
4049 type == BTRFS_FILE_EXTENT_PREALLOC) {
4050 /*
4051 * a | --- range to clone ---| b
4052 * | ------------- extent ------------- |
4053 */
4055 /* subtract range b */
4056 if (key.offset + datal > off + len)
4057 datal = off + len - key.offset;
4059 /* subtract range a */
4060 if (off > key.offset) {
4061 datao += off - key.offset;
4062 datal -= off - key.offset;
4063 }
4065 ret = btrfs_drop_extents(trans, root, inode,
4066 drop_start,
4067 new_key.offset + datal,
4068 1);
4069 if (ret) {
4070 if (ret != -EOPNOTSUPP)
4071 btrfs_abort_transaction(trans,
4072 ret);
4073 btrfs_end_transaction(trans);
4074 goto out;
4075 }
4077 ret = btrfs_insert_empty_item(trans, root, path,
4078 &new_key, size);
4079 if (ret) {
4080 btrfs_abort_transaction(trans, ret);
4081 btrfs_end_transaction(trans);
4082 goto out;
4083 }
4085 leaf = path->nodes[0];
4086 slot = path->slots[0];
4087 write_extent_buffer(leaf, buf,
4088 btrfs_item_ptr_offset(leaf, slot),
4089 size);
4091 extent = btrfs_item_ptr(leaf, slot,
4092 struct btrfs_file_extent_item);
4094 /* disko == 0 means it's a hole */
4095 if (!disko)
4096 datao = 0;
4098 btrfs_set_file_extent_offset(leaf, extent,
4099 datao);
4100 btrfs_set_file_extent_num_bytes(leaf, extent,
4101 datal);
4103 if (disko) {
4104 inode_add_bytes(inode, datal);
4105 ret = btrfs_inc_extent_ref(trans,
4106 root,
4107 disko, diskl, 0,
4108 root->root_key.objectid,
4109 btrfs_ino(BTRFS_I(inode)),
4110 new_key.offset - datao);
4111 if (ret) {
4112 btrfs_abort_transaction(trans,
4113 ret);
4114 btrfs_end_transaction(trans);
4115 goto out;
4117 }
4118 }
4119 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
4120 u64 skip = 0;
4121 u64 trim = 0;
4123 if (off > key.offset) {
4124 skip = off - key.offset;
4125 new_key.offset += skip;
4126 }
4128 if (key.offset + datal > off + len)
4129 trim = key.offset + datal - (off + len);
4131 if (comp && (skip || trim)) {
4132 ret = -EINVAL;
4133 btrfs_end_transaction(trans);
4134 goto out;
4135 }
4136 size -= skip + trim;
4137 datal -= skip + trim;
4139 ret = clone_copy_inline_extent(inode,
4140 trans, path,
4141 &new_key,
4142 drop_start,
4143 datal,
4144 skip, size, buf);
4145 if (ret) {
4146 if (ret != -EOPNOTSUPP)
4147 btrfs_abort_transaction(trans,
4148 ret);
4149 btrfs_end_transaction(trans);
4150 goto out;
4151 }
4152 leaf = path->nodes[0];
4153 slot = path->slots[0];
4154 }
4156 /* If we have an implicit hole (NO_HOLES feature). */
4157 if (drop_start < new_key.offset)
4158 clone_update_extent_map(BTRFS_I(inode), trans,
4159 NULL, drop_start,
4160 new_key.offset - drop_start);
4162 clone_update_extent_map(BTRFS_I(inode), trans,
4163 path, 0, 0);
4165 btrfs_mark_buffer_dirty(leaf);
4166 btrfs_release_path(path);
4168 last_dest_end = ALIGN(new_key.offset + datal,
4169 fs_info->sectorsize);
4170 ret = clone_finish_inode_update(trans, inode,
4171 last_dest_end,
4172 destoff, olen,
4173 no_time_update);
4174 if (ret)
4175 goto out;
4176 if (new_key.offset + datal >= destoff + len)
4177 break;
4178 }
4179 btrfs_release_path(path);
4180 key.offset = next_key_min_offset;
4182 if (fatal_signal_pending(current)) {
4183 ret = -EINTR;
4184 goto out;
4185 }
4186 }
4187 ret = 0;
4189 if (last_dest_end < destoff + len) {
4190 /*
4191 * We have an implicit hole (NO_HOLES feature is enabled) that
4192 * fully or partially overlaps our cloning range at its end.
4193 */
4194 btrfs_release_path(path);
4196 /*
4197 * 1 - remove extent(s)
4198 * 1 - inode update
4199 */
4200 trans = btrfs_start_transaction(root, 2);
4201 if (IS_ERR(trans)) {
4202 ret = PTR_ERR(trans);
4203 goto out;
4204 }
4205 ret = btrfs_drop_extents(trans, root, inode,
4206 last_dest_end, destoff + len, 1);
4207 if (ret) {
4208 if (ret != -EOPNOTSUPP)
4209 btrfs_abort_transaction(trans, ret);
4210 btrfs_end_transaction(trans);
4211 goto out;
4212 }
4213 clone_update_extent_map(BTRFS_I(inode), trans, NULL,
4214 last_dest_end,
4215 destoff + len - last_dest_end);
4216 ret = clone_finish_inode_update(trans, inode, destoff + len,
4217 destoff, olen, no_time_update);
4218 }
4220 out:
4221 btrfs_free_path(path);
4222 kvfree(buf);
4223 return ret;
4224 }
4226 static noinline int btrfs_clone_files(struct file *file, struct file *file_src,
4227 u64 off, u64 olen, u64 destoff)
4228 {
4229 struct inode *inode = file_inode(file);
4230 struct inode *src = file_inode(file_src);
4231 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4232 struct btrfs_root *root = BTRFS_I(inode)->root;
4233 int ret;
4234 u64 len = olen;
4235 u64 bs = fs_info->sb->s_blocksize;
4236 int same_inode = src == inode;
4238 /*
4239 * TODO:
4240 * - split compressed inline extents. annoying: we need to
4241 * decompress into destination's address_space (the file offset
4242 * may change, so source mapping won't do), then recompress (or
4243 * otherwise reinsert) a subrange.
4244 *
4245 * - split destination inode's inline extents. The inline extents can
4246 * be either compressed or non-compressed.
4247 */
4249 if (btrfs_root_readonly(root))
4250 return -EROFS;
4252 if (file_src->f_path.mnt != file->f_path.mnt ||
4253 src->i_sb != inode->i_sb)
4254 return -EXDEV;
4256 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
4257 return -EISDIR;
4259 if (!same_inode) {
4260 btrfs_double_inode_lock(src, inode);
4261 } else {
4262 inode_lock(src);
4263 }
4265 /* don't make the dst file partly checksummed */
4266 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
4267 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
4268 ret = -EINVAL;
4269 goto out_unlock;
4270 }
4272 /* determine range to clone */
4273 ret = -EINVAL;
4274 if (off + len > src->i_size || off + len < off)
4275 goto out_unlock;
4276 if (len == 0)
4277 olen = len = src->i_size - off;
4278 /* if we extend to eof, continue to block boundary */
4279 if (off + len == src->i_size)
4280 len = ALIGN(src->i_size, bs) - off;
4282 if (len == 0) {
4283 ret = 0;
4284 goto out_unlock;
4285 }
4287 /* verify the end result is block aligned */
4288 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
4289 !IS_ALIGNED(destoff, bs))
4290 goto out_unlock;
4292 /* verify if ranges are overlapped within the same file */
4293 if (same_inode) {
4294 if (destoff + len > off && destoff < off + len)
4295 goto out_unlock;
4296 }
4298 if (destoff > inode->i_size) {
4299 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
4300 if (ret)
4301 goto out_unlock;
4302 }
4304 /*
4305 * Lock the target range too. Right after we replace the file extent
4306 * items in the fs tree (which now point to the cloned data), we might
4307 * have a worker replace them with extent items relative to a write
4308 * operation that was issued before this clone operation (i.e. confront
4309 * with inode.c:btrfs_finish_ordered_io).
4310 */
4311 if (same_inode) {
4312 u64 lock_start = min_t(u64, off, destoff);
4313 u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
4315 ret = lock_extent_range(src, lock_start, lock_len, true);
4316 } else {
4317 ret = btrfs_double_extent_lock(src, off, inode, destoff, len,
4318 true);
4319 }
4320 ASSERT(ret == 0);
4321 if (WARN_ON(ret)) {
4322 /* ranges in the io trees already unlocked */
4323 goto out_unlock;
4324 }
4326 ret = btrfs_clone(src, inode, off, olen, len, destoff, 0);
4328 if (same_inode) {
4329 u64 lock_start = min_t(u64, off, destoff);
4330 u64 lock_end = max_t(u64, off, destoff) + len - 1;
4332 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
4333 } else {
4334 btrfs_double_extent_unlock(src, off, inode, destoff, len);
4335 }
4336 /*
4337 * Truncate page cache pages so that future reads will see the cloned
4338 * data immediately and not the previous data.
4339 */
4340 truncate_inode_pages_range(&inode->i_data,
4341 round_down(destoff, PAGE_SIZE),
4342 round_up(destoff + len, PAGE_SIZE) - 1);
4343 out_unlock:
4344 if (!same_inode)
4345 btrfs_double_inode_unlock(src, inode);
4346 else
4347 inode_unlock(src);
4348 return ret;
4349 }
4351 int btrfs_clone_file_range(struct file *src_file, loff_t off,
4352 struct file *dst_file, loff_t destoff, u64 len)
4353 {
4354 return btrfs_clone_files(dst_file, src_file, off, len, destoff);
4355 }
4357 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
4358 {
4359 struct inode *inode = file_inode(file);
4360 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4361 struct btrfs_root *root = BTRFS_I(inode)->root;
4362 struct btrfs_root *new_root;
4363 struct btrfs_dir_item *di;
4364 struct btrfs_trans_handle *trans;
4365 struct btrfs_path *path;
4366 struct btrfs_key location;
4367 struct btrfs_disk_key disk_key;
4368 u64 objectid = 0;
4369 u64 dir_id;
4370 int ret;
4372 if (!capable(CAP_SYS_ADMIN))
4373 return -EPERM;
4375 ret = mnt_want_write_file(file);
4376 if (ret)
4377 return ret;
4379 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
4380 ret = -EFAULT;
4381 goto out;
4382 }
4384 if (!objectid)
4385 objectid = BTRFS_FS_TREE_OBJECTID;
4387 location.objectid = objectid;
4388 location.type = BTRFS_ROOT_ITEM_KEY;
4389 location.offset = (u64)-1;
4391 new_root = btrfs_read_fs_root_no_name(fs_info, &location);
4392 if (IS_ERR(new_root)) {
4393 ret = PTR_ERR(new_root);
4394 goto out;
4395 }
4396 if (!is_fstree(new_root->objectid)) {
4397 ret = -ENOENT;
4398 goto out;
4399 }
4401 path = btrfs_alloc_path();
4402 if (!path) {
4403 ret = -ENOMEM;
4404 goto out;
4405 }
4406 path->leave_spinning = 1;
4408 trans = btrfs_start_transaction(root, 1);
4409 if (IS_ERR(trans)) {
4410 btrfs_free_path(path);
4411 ret = PTR_ERR(trans);
4412 goto out;
4413 }
4415 dir_id = btrfs_super_root_dir(fs_info->super_copy);
4416 di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
4417 dir_id, "default", 7, 1);
4418 if (IS_ERR_OR_NULL(di)) {
4419 btrfs_free_path(path);
4420 btrfs_end_transaction(trans);
4421 btrfs_err(fs_info,
4422 "Umm, you don't have the default diritem, this isn't going to work");
4423 ret = -ENOENT;
4424 goto out;
4425 }
4427 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
4428 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
4429 btrfs_mark_buffer_dirty(path->nodes[0]);
4430 btrfs_free_path(path);
4432 btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
4433 btrfs_end_transaction(trans);
4434 out:
4435 mnt_drop_write_file(file);
4436 return ret;
4437 }
4439 static void get_block_group_info(struct list_head *groups_list,
4440 struct btrfs_ioctl_space_info *space)
4441 {
4442 struct btrfs_block_group_cache *block_group;
4444 space->total_bytes = 0;
4445 space->used_bytes = 0;
4446 space->flags = 0;
4447 list_for_each_entry(block_group, groups_list, list) {
4448 space->flags = block_group->flags;
4449 space->total_bytes += block_group->key.offset;
4450 space->used_bytes +=
4451 btrfs_block_group_used(&block_group->item);
4452 }
4453 }
4455 static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
4456 void __user *arg)
4457 {
4458 struct btrfs_ioctl_space_args space_args;
4459 struct btrfs_ioctl_space_info space;
4460 struct btrfs_ioctl_space_info *dest;
4461 struct btrfs_ioctl_space_info *dest_orig;
4462 struct btrfs_ioctl_space_info __user *user_dest;
4463 struct btrfs_space_info *info;
4464 static const u64 types[] = {
4465 BTRFS_BLOCK_GROUP_DATA,
4466 BTRFS_BLOCK_GROUP_SYSTEM,
4467 BTRFS_BLOCK_GROUP_METADATA,
4468 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA
4469 };
4470 int num_types = 4;
4471 int alloc_size;
4472 int ret = 0;
4473 u64 slot_count = 0;
4474 int i, c;
4476 if (copy_from_user(&space_args,
4477 (struct btrfs_ioctl_space_args __user *)arg,
4478 sizeof(space_args)))
4479 return -EFAULT;
4481 for (i = 0; i < num_types; i++) {
4482 struct btrfs_space_info *tmp;
4484 info = NULL;
4485 rcu_read_lock();
4486 list_for_each_entry_rcu(tmp, &fs_info->space_info,
4487 list) {
4488 if (tmp->flags == types[i]) {
4489 info = tmp;
4490 break;
4491 }
4492 }
4493 rcu_read_unlock();
4495 if (!info)
4496 continue;
4498 down_read(&info->groups_sem);
4499 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4500 if (!list_empty(&info->block_groups[c]))
4501 slot_count++;
4502 }
4503 up_read(&info->groups_sem);
4504 }
4506 /*
4507 * Global block reserve, exported as a space_info
4508 */
4509 slot_count++;
4511 /* space_slots == 0 means they are asking for a count */
4512 if (space_args.space_slots == 0) {
4513 space_args.total_spaces = slot_count;
4514 goto out;
4515 }
4517 slot_count = min_t(u64, space_args.space_slots, slot_count);
4519 alloc_size = sizeof(*dest) * slot_count;
4521 /* we generally have at most 6 or so space infos, one for each raid
4522 * level. So, a whole page should be more than enough for everyone
4523 */
4524 if (alloc_size > PAGE_SIZE)
4525 return -ENOMEM;
4527 space_args.total_spaces = 0;
4528 dest = kmalloc(alloc_size, GFP_KERNEL);
4529 if (!dest)
4530 return -ENOMEM;
4531 dest_orig = dest;
4533 /* now we have a buffer to copy into */
4534 for (i = 0; i < num_types; i++) {
4535 struct btrfs_space_info *tmp;
4537 if (!slot_count)
4538 break;
4540 info = NULL;
4541 rcu_read_lock();
4542 list_for_each_entry_rcu(tmp, &fs_info->space_info,
4543 list) {
4544 if (tmp->flags == types[i]) {
4545 info = tmp;
4546 break;
4547 }
4548 }
4549 rcu_read_unlock();
4551 if (!info)
4552 continue;
4553 down_read(&info->groups_sem);
4554 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4555 if (!list_empty(&info->block_groups[c])) {
4556 get_block_group_info(&info->block_groups[c],
4557 &space);
4558 memcpy(dest, &space, sizeof(space));
4559 dest++;
4560 space_args.total_spaces++;
4561 slot_count--;
4562 }
4563 if (!slot_count)
4564 break;
4565 }
4566 up_read(&info->groups_sem);
4567 }
4569 /*
4570 * Add global block reserve
4571 */
4572 if (slot_count) {
4573 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
4575 spin_lock(&block_rsv->lock);
4576 space.total_bytes = block_rsv->size;
4577 space.used_bytes = block_rsv->size - block_rsv->reserved;
4578 spin_unlock(&block_rsv->lock);
4579 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
4580 memcpy(dest, &space, sizeof(space));
4581 space_args.total_spaces++;
4582 }
4584 user_dest = (struct btrfs_ioctl_space_info __user *)
4585 (arg + sizeof(struct btrfs_ioctl_space_args));
4587 if (copy_to_user(user_dest, dest_orig, alloc_size))
4588 ret = -EFAULT;
4590 kfree(dest_orig);
4591 out:
4592 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4593 ret = -EFAULT;
4595 return ret;
4596 }
4598 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4599 void __user *argp)
4600 {
4601 struct btrfs_trans_handle *trans;
4602 u64 transid;
4603 int ret;
4605 trans = btrfs_attach_transaction_barrier(root);
4606 if (IS_ERR(trans)) {
4607 if (PTR_ERR(trans) != -ENOENT)
4608 return PTR_ERR(trans);
4610 /* No running transaction, don't bother */
4611 transid = root->fs_info->last_trans_committed;
4612 goto out;
4613 }
4614 transid = trans->transid;
4615 ret = btrfs_commit_transaction_async(trans, 0);
4616 if (ret) {
4617 btrfs_end_transaction(trans);
4618 return ret;
4619 }
4620 out:
4621 if (argp)
4622 if (copy_to_user(argp, &transid, sizeof(transid)))
4623 return -EFAULT;
4624 return 0;
4625 }
4627 static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,
4628 void __user *argp)
4629 {
4630 u64 transid;
4632 if (argp) {
4633 if (copy_from_user(&transid, argp, sizeof(transid)))
4634 return -EFAULT;
4635 } else {
4636 transid = 0; /* current trans */
4637 }
4638 return btrfs_wait_for_commit(fs_info, transid);
4639 }
4641 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4642 {
4643 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
4644 struct btrfs_ioctl_scrub_args *sa;
4645 int ret;
4647 if (!capable(CAP_SYS_ADMIN))
4648 return -EPERM;
4650 sa = memdup_user(arg, sizeof(*sa));
4651 if (IS_ERR(sa))
4652 return PTR_ERR(sa);
4654 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4655 ret = mnt_want_write_file(file);
4656 if (ret)
4657 goto out;
4658 }
4660 ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,
4661 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4662 0);
4664 if (copy_to_user(arg, sa, sizeof(*sa)))
4665 ret = -EFAULT;
4667 if (!(sa->flags & BTRFS_SCRUB_READONLY))
4668 mnt_drop_write_file(file);
4669 out:
4670 kfree(sa);
4671 return ret;
4672 }
4674 static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)
4675 {
4676 if (!capable(CAP_SYS_ADMIN))
4677 return -EPERM;
4679 return btrfs_scrub_cancel(fs_info);
4680 }
4682 static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
4683 void __user *arg)
4684 {
4685 struct btrfs_ioctl_scrub_args *sa;
4686 int ret;
4688 if (!capable(CAP_SYS_ADMIN))
4689 return -EPERM;
4691 sa = memdup_user(arg, sizeof(*sa));
4692 if (IS_ERR(sa))
4693 return PTR_ERR(sa);
4695 ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
4697 if (copy_to_user(arg, sa, sizeof(*sa)))
4698 ret = -EFAULT;
4700 kfree(sa);
4701 return ret;
4702 }
4704 static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
4705 void __user *arg)
4706 {
4707 struct btrfs_ioctl_get_dev_stats *sa;
4708 int ret;
4710 sa = memdup_user(arg, sizeof(*sa));
4711 if (IS_ERR(sa))
4712 return PTR_ERR(sa);
4714 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4715 kfree(sa);
4716 return -EPERM;
4717 }
4719 ret = btrfs_get_dev_stats(fs_info, sa);
4721 if (copy_to_user(arg, sa, sizeof(*sa)))
4722 ret = -EFAULT;
4724 kfree(sa);
4725 return ret;
4726 }
4728 static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
4729 void __user *arg)
4730 {
4731 struct btrfs_ioctl_dev_replace_args *p;
4732 int ret;
4734 if (!capable(CAP_SYS_ADMIN))
4735 return -EPERM;
4737 p = memdup_user(arg, sizeof(*p));
4738 if (IS_ERR(p))
4739 return PTR_ERR(p);
4741 switch (p->cmd) {
4742 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4743 if (sb_rdonly(fs_info->sb)) {
4744 ret = -EROFS;
4745 goto out;
4746 }
4747 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
4748 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4749 } else {
4750 ret = btrfs_dev_replace_by_ioctl(fs_info, p);
4751 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
4752 }
4753 break;
4754 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4755 btrfs_dev_replace_status(fs_info, p);
4756 ret = 0;
4757 break;
4758 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4759 p->result = btrfs_dev_replace_cancel(fs_info);
4760 ret = 0;
4761 break;
4762 default:
4763 ret = -EINVAL;
4764 break;
4765 }
4767 if (copy_to_user(arg, p, sizeof(*p)))
4768 ret = -EFAULT;
4769 out:
4770 kfree(p);
4771 return ret;
4772 }
4774 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4775 {
4776 int ret = 0;
4777 int i;
4778 u64 rel_ptr;
4779 int size;
4780 struct btrfs_ioctl_ino_path_args *ipa = NULL;
4781 struct inode_fs_paths *ipath = NULL;
4782 struct btrfs_path *path;
4784 if (!capable(CAP_DAC_READ_SEARCH))
4785 return -EPERM;
4787 path = btrfs_alloc_path();
4788 if (!path) {
4789 ret = -ENOMEM;
4790 goto out;
4791 }
4793 ipa = memdup_user(arg, sizeof(*ipa));
4794 if (IS_ERR(ipa)) {
4795 ret = PTR_ERR(ipa);
4796 ipa = NULL;
4797 goto out;
4798 }
4800 size = min_t(u32, ipa->size, 4096);
4801 ipath = init_ipath(size, root, path);
4802 if (IS_ERR(ipath)) {
4803 ret = PTR_ERR(ipath);
4804 ipath = NULL;
4805 goto out;
4806 }
4808 ret = paths_from_inode(ipa->inum, ipath);
4809 if (ret < 0)
4810 goto out;
4812 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4813 rel_ptr = ipath->fspath->val[i] -
4814 (u64)(unsigned long)ipath->fspath->val;
4815 ipath->fspath->val[i] = rel_ptr;
4816 }
4818 ret = copy_to_user((void __user *)(unsigned long)ipa->fspath,
4819 ipath->fspath, size);
4820 if (ret) {
4821 ret = -EFAULT;
4822 goto out;
4823 }
4825 out:
4826 btrfs_free_path(path);
4827 free_ipath(ipath);
4828 kfree(ipa);
4830 return ret;
4831 }
4833 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4834 {
4835 struct btrfs_data_container *inodes = ctx;
4836 const size_t c = 3 * sizeof(u64);
4838 if (inodes->bytes_left >= c) {
4839 inodes->bytes_left -= c;
4840 inodes->val[inodes->elem_cnt] = inum;
4841 inodes->val[inodes->elem_cnt + 1] = offset;
4842 inodes->val[inodes->elem_cnt + 2] = root;
4843 inodes->elem_cnt += 3;
4844 } else {
4845 inodes->bytes_missing += c - inodes->bytes_left;
4846 inodes->bytes_left = 0;
4847 inodes->elem_missed += 3;
4848 }
4850 return 0;
4851 }
4853 static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,
4854 void __user *arg, int version)
4855 {
4856 int ret = 0;
4857 int size;
4858 struct btrfs_ioctl_logical_ino_args *loi;
4859 struct btrfs_data_container *inodes = NULL;
4860 struct btrfs_path *path = NULL;
4861 bool ignore_offset;
4863 if (!capable(CAP_SYS_ADMIN))
4864 return -EPERM;
4866 loi = memdup_user(arg, sizeof(*loi));
4867 if (IS_ERR(loi))
4868 return PTR_ERR(loi);
4870 if (version == 1) {
4871 ignore_offset = false;
4872 size = min_t(u32, loi->size, SZ_64K);
4873 } else {
4874 /* All reserved bits must be 0 for now */
4875 if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) {
4876 ret = -EINVAL;
4877 goto out_loi;
4878 }
4879 /* Only accept flags we have defined so far */
4880 if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) {
4881 ret = -EINVAL;
4882 goto out_loi;
4883 }
4884 ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET;
4885 size = min_t(u32, loi->size, SZ_16M);
4886 }
4888 path = btrfs_alloc_path();
4889 if (!path) {
4890 ret = -ENOMEM;
4891 goto out;
4892 }
4894 inodes = init_data_container(size);
4895 if (IS_ERR(inodes)) {
4896 ret = PTR_ERR(inodes);
4897 inodes = NULL;
4898 goto out;
4899 }
4901 ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
4902 build_ino_list, inodes, ignore_offset);
4903 if (ret == -EINVAL)
4904 ret = -ENOENT;
4905 if (ret < 0)
4906 goto out;
4908 ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes,
4909 size);
4910 if (ret)
4911 ret = -EFAULT;
4913 out:
4914 btrfs_free_path(path);
4915 kvfree(inodes);
4916 out_loi:
4917 kfree(loi);
4919 return ret;
4920 }
4922 void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info,
4923 struct btrfs_ioctl_balance_args *bargs)
4924 {
4925 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4927 bargs->flags = bctl->flags;
4929 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags))
4930 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4931 if (atomic_read(&fs_info->balance_pause_req))
4932 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4933 if (atomic_read(&fs_info->balance_cancel_req))
4934 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4936 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4937 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4938 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4940 spin_lock(&fs_info->balance_lock);
4941 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4942 spin_unlock(&fs_info->balance_lock);
4943 }
4945 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4946 {
4947 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4948 struct btrfs_fs_info *fs_info = root->fs_info;
4949 struct btrfs_ioctl_balance_args *bargs;
4950 struct btrfs_balance_control *bctl;
4951 bool need_unlock; /* for mut. excl. ops lock */
4952 int ret;
4954 if (!capable(CAP_SYS_ADMIN))
4955 return -EPERM;
4957 ret = mnt_want_write_file(file);
4958 if (ret)
4959 return ret;
4961 again:
4962 if (!test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
4963 mutex_lock(&fs_info->balance_mutex);
4964 need_unlock = true;
4965 goto locked;
4966 }
4968 /*
4969 * mut. excl. ops lock is locked. Three possibilities:
4970 * (1) some other op is running
4971 * (2) balance is running
4972 * (3) balance is paused -- special case (think resume)
4973 */
4974 mutex_lock(&fs_info->balance_mutex);
4975 if (fs_info->balance_ctl) {
4976 /* this is either (2) or (3) */
4977 if (!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4978 mutex_unlock(&fs_info->balance_mutex);
4979 /*
4980 * Lock released to allow other waiters to continue,
4981 * we'll reexamine the status again.
4982 */
4983 mutex_lock(&fs_info->balance_mutex);
4985 if (fs_info->balance_ctl &&
4986 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4987 /* this is (3) */
4988 need_unlock = false;
4989 goto locked;
4990 }
4992 mutex_unlock(&fs_info->balance_mutex);
4993 goto again;
4994 } else {
4995 /* this is (2) */
4996 mutex_unlock(&fs_info->balance_mutex);
4997 ret = -EINPROGRESS;
4998 goto out;
4999 }
5000 } else {
5001 /* this is (1) */
5002 mutex_unlock(&fs_info->balance_mutex);
5003 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
5004 goto out;
5005 }
5007 locked:
5008 BUG_ON(!test_bit(BTRFS_FS_EXCL_OP, &fs_info->flags));
5010 if (arg) {
5011 bargs = memdup_user(arg, sizeof(*bargs));
5012 if (IS_ERR(bargs)) {
5013 ret = PTR_ERR(bargs);
5014 goto out_unlock;
5015 }
5017 if (bargs->flags & BTRFS_BALANCE_RESUME) {
5018 if (!fs_info->balance_ctl) {
5019 ret = -ENOTCONN;
5020 goto out_bargs;
5021 }
5023 bctl = fs_info->balance_ctl;
5024 spin_lock(&fs_info->balance_lock);
5025 bctl->flags |= BTRFS_BALANCE_RESUME;
5026 spin_unlock(&fs_info->balance_lock);
5028 goto do_balance;
5029 }
5030 } else {
5031 bargs = NULL;
5032 }
5034 if (fs_info->balance_ctl) {
5035 ret = -EINPROGRESS;
5036 goto out_bargs;
5037 }
5039 bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
5040 if (!bctl) {
5041 ret = -ENOMEM;
5042 goto out_bargs;
5043 }
5045 if (arg) {
5046 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
5047 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
5048 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
5050 bctl->flags = bargs->flags;
5051 } else {
5052 /* balance everything - no filters */
5053 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
5054 }
5056 if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
5057 ret = -EINVAL;
5058 goto out_bctl;
5059 }
5061 do_balance:
5062 /*
5063 * Ownership of bctl and filesystem flag BTRFS_FS_EXCL_OP goes to
5064 * btrfs_balance. bctl is freed in reset_balance_state, or, if
5065 * restriper was paused all the way until unmount, in free_fs_info.
5066 * The flag should be cleared after reset_balance_state.
5067 */
5068 need_unlock = false;
5070 ret = btrfs_balance(fs_info, bctl, bargs);
5071 bctl = NULL;
5073 if (arg) {
5074 if (copy_to_user(arg, bargs, sizeof(*bargs)))
5075 ret = -EFAULT;
5076 }
5078 out_bctl:
5079 kfree(bctl);
5080 out_bargs:
5081 kfree(bargs);
5082 out_unlock:
5083 mutex_unlock(&fs_info->balance_mutex);
5084 if (need_unlock)
5085 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
5086 out:
5087 mnt_drop_write_file(file);
5088 return ret;
5089 }
5091 static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
5092 {
5093 if (!capable(CAP_SYS_ADMIN))
5094 return -EPERM;
5096 switch (cmd) {
5097 case BTRFS_BALANCE_CTL_PAUSE:
5098 return btrfs_pause_balance(fs_info);
5099 case BTRFS_BALANCE_CTL_CANCEL:
5100 return btrfs_cancel_balance(fs_info);
5101 }
5103 return -EINVAL;
5104 }
5106 static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
5107 void __user *arg)
5108 {
5109 struct btrfs_ioctl_balance_args *bargs;
5110 int ret = 0;
5112 if (!capable(CAP_SYS_ADMIN))
5113 return -EPERM;
5115 mutex_lock(&fs_info->balance_mutex);
5116 if (!fs_info->balance_ctl) {
5117 ret = -ENOTCONN;
5118 goto out;
5119 }
5121 bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
5122 if (!bargs) {
5123 ret = -ENOMEM;
5124 goto out;
5125 }
5127 btrfs_update_ioctl_balance_args(fs_info, bargs);
5129 if (copy_to_user(arg, bargs, sizeof(*bargs)))
5130 ret = -EFAULT;
5132 kfree(bargs);
5133 out:
5134 mutex_unlock(&fs_info->balance_mutex);
5135 return ret;
5136 }
5138 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
5139 {
5140 struct inode *inode = file_inode(file);
5141 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5142 struct btrfs_ioctl_quota_ctl_args *sa;
5143 int ret;
5145 if (!capable(CAP_SYS_ADMIN))
5146 return -EPERM;
5148 ret = mnt_want_write_file(file);
5149 if (ret)
5150 return ret;
5152 sa = memdup_user(arg, sizeof(*sa));
5153 if (IS_ERR(sa)) {
5154 ret = PTR_ERR(sa);
5155 goto drop_write;
5156 }
5158 down_write(&fs_info->subvol_sem);
5160 switch (sa->cmd) {
5161 case BTRFS_QUOTA_CTL_ENABLE:
5162 ret = btrfs_quota_enable(fs_info);
5163 break;
5164 case BTRFS_QUOTA_CTL_DISABLE:
5165 ret = btrfs_quota_disable(fs_info);
5166 break;
5167 default:
5168 ret = -EINVAL;
5169 break;
5170 }
5172 kfree(sa);
5173 up_write(&fs_info->subvol_sem);
5174 drop_write:
5175 mnt_drop_write_file(file);
5176 return ret;
5177 }
5179 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
5180 {
5181 struct inode *inode = file_inode(file);
5182 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5183 struct btrfs_root *root = BTRFS_I(inode)->root;
5184 struct btrfs_ioctl_qgroup_assign_args *sa;
5185 struct btrfs_trans_handle *trans;
5186 int ret;
5187 int err;
5189 if (!capable(CAP_SYS_ADMIN))
5190 return -EPERM;
5192 ret = mnt_want_write_file(file);
5193 if (ret)
5194 return ret;
5196 sa = memdup_user(arg, sizeof(*sa));
5197 if (IS_ERR(sa)) {
5198 ret = PTR_ERR(sa);
5199 goto drop_write;
5200 }
5202 trans = btrfs_join_transaction(root);
5203 if (IS_ERR(trans)) {
5204 ret = PTR_ERR(trans);
5205 goto out;
5206 }
5208 if (sa->assign) {
5209 ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst);
5210 } else {
5211 ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst);
5212 }
5214 /* update qgroup status and info */
5215 err = btrfs_run_qgroups(trans);
5216 if (err < 0)
5217 btrfs_handle_fs_error(fs_info, err,
5218 "failed to update qgroup status and info");
5219 err = btrfs_end_transaction(trans);
5220 if (err && !ret)
5221 ret = err;
5223 out:
5224 kfree(sa);
5225 drop_write:
5226 mnt_drop_write_file(file);
5227 return ret;
5228 }
5230 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
5231 {
5232 struct inode *inode = file_inode(file);
5233 struct btrfs_root *root = BTRFS_I(inode)->root;
5234 struct btrfs_ioctl_qgroup_create_args *sa;
5235 struct btrfs_trans_handle *trans;
5236 int ret;
5237 int err;
5239 if (!capable(CAP_SYS_ADMIN))
5240 return -EPERM;
5242 ret = mnt_want_write_file(file);
5243 if (ret)
5244 return ret;
5246 sa = memdup_user(arg, sizeof(*sa));
5247 if (IS_ERR(sa)) {
5248 ret = PTR_ERR(sa);
5249 goto drop_write;
5250 }
5252 if (!sa->qgroupid) {
5253 ret = -EINVAL;
5254 goto out;
5255 }
5257 trans = btrfs_join_transaction(root);
5258 if (IS_ERR(trans)) {
5259 ret = PTR_ERR(trans);
5260 goto out;
5261 }
5263 if (sa->create) {
5264 ret = btrfs_create_qgroup(trans, sa->qgroupid);
5265 } else {
5266 ret = btrfs_remove_qgroup(trans, sa->qgroupid);
5267 }
5269 err = btrfs_end_transaction(trans);
5270 if (err && !ret)
5271 ret = err;
5273 out:
5274 kfree(sa);
5275 drop_write:
5276 mnt_drop_write_file(file);
5277 return ret;
5278 }
5280 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
5281 {
5282 struct inode *inode = file_inode(file);
5283 struct btrfs_root *root = BTRFS_I(inode)->root;
5284 struct btrfs_ioctl_qgroup_limit_args *sa;
5285 struct btrfs_trans_handle *trans;
5286 int ret;
5287 int err;
5288 u64 qgroupid;
5290 if (!capable(CAP_SYS_ADMIN))
5291 return -EPERM;
5293 ret = mnt_want_write_file(file);
5294 if (ret)
5295 return ret;
5297 sa = memdup_user(arg, sizeof(*sa));
5298 if (IS_ERR(sa)) {
5299 ret = PTR_ERR(sa);
5300 goto drop_write;
5301 }
5303 trans = btrfs_join_transaction(root);
5304 if (IS_ERR(trans)) {
5305 ret = PTR_ERR(trans);
5306 goto out;
5307 }
5309 qgroupid = sa->qgroupid;
5310 if (!qgroupid) {
5311 /* take the current subvol as qgroup */
5312 qgroupid = root->root_key.objectid;
5313 }
5315 ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim);
5317 err = btrfs_end_transaction(trans);
5318 if (err && !ret)
5319 ret = err;
5321 out:
5322 kfree(sa);
5323 drop_write:
5324 mnt_drop_write_file(file);
5325 return ret;
5326 }
5328 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
5329 {
5330 struct inode *inode = file_inode(file);
5331 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5332 struct btrfs_ioctl_quota_rescan_args *qsa;
5333 int ret;
5335 if (!capable(CAP_SYS_ADMIN))
5336 return -EPERM;
5338 ret = mnt_want_write_file(file);
5339 if (ret)
5340 return ret;
5342 qsa = memdup_user(arg, sizeof(*qsa));
5343 if (IS_ERR(qsa)) {
5344 ret = PTR_ERR(qsa);
5345 goto drop_write;
5346 }
5348 if (qsa->flags) {
5349 ret = -EINVAL;
5350 goto out;
5351 }
5353 ret = btrfs_qgroup_rescan(fs_info);
5355 out:
5356 kfree(qsa);
5357 drop_write:
5358 mnt_drop_write_file(file);
5359 return ret;
5360 }
5362 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
5363 {
5364 struct inode *inode = file_inode(file);
5365 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5366 struct btrfs_ioctl_quota_rescan_args *qsa;
5367 int ret = 0;
5369 if (!capable(CAP_SYS_ADMIN))
5370 return -EPERM;
5372 qsa = kzalloc(sizeof(*qsa), GFP_KERNEL);
5373 if (!qsa)
5374 return -ENOMEM;
5376 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
5377 qsa->flags = 1;
5378 qsa->progress = fs_info->qgroup_rescan_progress.objectid;
5379 }
5381 if (copy_to_user(arg, qsa, sizeof(*qsa)))
5382 ret = -EFAULT;
5384 kfree(qsa);
5385 return ret;
5386 }
5388 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
5389 {
5390 struct inode *inode = file_inode(file);
5391 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5393 if (!capable(CAP_SYS_ADMIN))
5394 return -EPERM;
5396 return btrfs_qgroup_wait_for_completion(fs_info, true);
5397 }
5399 static long _btrfs_ioctl_set_received_subvol(struct file *file,
5400 struct btrfs_ioctl_received_subvol_args *sa)
5401 {
5402 struct inode *inode = file_inode(file);
5403 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5404 struct btrfs_root *root = BTRFS_I(inode)->root;
5405 struct btrfs_root_item *root_item = &root->root_item;
5406 struct btrfs_trans_handle *trans;
5407 struct timespec64 ct = current_time(inode);
5408 int ret = 0;
5409 int received_uuid_changed;
5411 if (!inode_owner_or_capable(inode))
5412 return -EPERM;
5414 ret = mnt_want_write_file(file);
5415 if (ret < 0)
5416 return ret;
5418 down_write(&fs_info->subvol_sem);
5420 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
5421 ret = -EINVAL;
5422 goto out;
5423 }
5425 if (btrfs_root_readonly(root)) {
5426 ret = -EROFS;
5427 goto out;
5428 }
5430 /*
5431 * 1 - root item
5432 * 2 - uuid items (received uuid + subvol uuid)
5433 */
5434 trans = btrfs_start_transaction(root, 3);
5435 if (IS_ERR(trans)) {
5436 ret = PTR_ERR(trans);
5437 trans = NULL;
5438 goto out;
5439 }
5441 sa->rtransid = trans->transid;
5442 sa->rtime.sec = ct.tv_sec;
5443 sa->rtime.nsec = ct.tv_nsec;
5445 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
5446 BTRFS_UUID_SIZE);
5447 if (received_uuid_changed &&
5448 !btrfs_is_empty_uuid(root_item->received_uuid)) {
5449 ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid,
5450 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5451 root->root_key.objectid);
5452 if (ret && ret != -ENOENT) {
5453 btrfs_abort_transaction(trans, ret);
5454 btrfs_end_transaction(trans);
5455 goto out;
5456 }
5457 }
5458 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
5459 btrfs_set_root_stransid(root_item, sa->stransid);
5460 btrfs_set_root_rtransid(root_item, sa->rtransid);
5461 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
5462 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
5463 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
5464 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
5466 ret = btrfs_update_root(trans, fs_info->tree_root,
5467 &root->root_key, &root->root_item);
5468 if (ret < 0) {
5469 btrfs_end_transaction(trans);
5470 goto out;
5471 }
5472 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
5473 ret = btrfs_uuid_tree_add(trans, sa->uuid,
5474 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5475 root->root_key.objectid);
5476 if (ret < 0 && ret != -EEXIST) {
5477 btrfs_abort_transaction(trans, ret);
5478 btrfs_end_transaction(trans);
5479 goto out;
5480 }
5481 }
5482 ret = btrfs_commit_transaction(trans);
5483 out:
5484 up_write(&fs_info->subvol_sem);
5485 mnt_drop_write_file(file);
5486 return ret;
5487 }
5489 #ifdef CONFIG_64BIT
5490 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
5491 void __user *arg)
5492 {
5493 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
5494 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
5495 int ret = 0;
5497 args32 = memdup_user(arg, sizeof(*args32));
5498 if (IS_ERR(args32))
5499 return PTR_ERR(args32);
5501 args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
5502 if (!args64) {
5503 ret = -ENOMEM;
5504 goto out;
5505 }
5507 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
5508 args64->stransid = args32->stransid;
5509 args64->rtransid = args32->rtransid;
5510 args64->stime.sec = args32->stime.sec;
5511 args64->stime.nsec = args32->stime.nsec;
5512 args64->rtime.sec = args32->rtime.sec;
5513 args64->rtime.nsec = args32->rtime.nsec;
5514 args64->flags = args32->flags;
5516 ret = _btrfs_ioctl_set_received_subvol(file, args64);
5517 if (ret)
5518 goto out;
5520 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
5521 args32->stransid = args64->stransid;
5522 args32->rtransid = args64->rtransid;
5523 args32->stime.sec = args64->stime.sec;
5524 args32->stime.nsec = args64->stime.nsec;
5525 args32->rtime.sec = args64->rtime.sec;
5526 args32->rtime.nsec = args64->rtime.nsec;
5527 args32->flags = args64->flags;
5529 ret = copy_to_user(arg, args32, sizeof(*args32));
5530 if (ret)
5531 ret = -EFAULT;
5533 out:
5534 kfree(args32);
5535 kfree(args64);
5536 return ret;
5537 }
5538 #endif
5540 static long btrfs_ioctl_set_received_subvol(struct file *file,
5541 void __user *arg)
5542 {
5543 struct btrfs_ioctl_received_subvol_args *sa = NULL;
5544 int ret = 0;
5546 sa = memdup_user(arg, sizeof(*sa));
5547 if (IS_ERR(sa))
5548 return PTR_ERR(sa);
5550 ret = _btrfs_ioctl_set_received_subvol(file, sa);
5552 if (ret)
5553 goto out;
5555 ret = copy_to_user(arg, sa, sizeof(*sa));
5556 if (ret)
5557 ret = -EFAULT;
5559 out:
5560 kfree(sa);
5561 return ret;
5562 }
5564 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
5565 {
5566 struct inode *inode = file_inode(file);
5567 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5568 size_t len;
5569 int ret;
5570 char label[BTRFS_LABEL_SIZE];
5572 spin_lock(&fs_info->super_lock);
5573 memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5574 spin_unlock(&fs_info->super_lock);
5576 len = strnlen(label, BTRFS_LABEL_SIZE);
5578 if (len == BTRFS_LABEL_SIZE) {
5579 btrfs_warn(fs_info,
5580 "label is too long, return the first %zu bytes",
5581 --len);
5582 }
5584 ret = copy_to_user(arg, label, len);
5586 return ret ? -EFAULT : 0;
5587 }
5589 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5590 {
5591 struct inode *inode = file_inode(file);
5592 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5593 struct btrfs_root *root = BTRFS_I(inode)->root;
5594 struct btrfs_super_block *super_block = fs_info->super_copy;
5595 struct btrfs_trans_handle *trans;
5596 char label[BTRFS_LABEL_SIZE];
5597 int ret;
5599 if (!capable(CAP_SYS_ADMIN))
5600 return -EPERM;
5602 if (copy_from_user(label, arg, sizeof(label)))
5603 return -EFAULT;
5605 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5606 btrfs_err(fs_info,
5607 "unable to set label with more than %d bytes",
5608 BTRFS_LABEL_SIZE - 1);
5609 return -EINVAL;
5610 }
5612 ret = mnt_want_write_file(file);
5613 if (ret)
5614 return ret;
5616 trans = btrfs_start_transaction(root, 0);
5617 if (IS_ERR(trans)) {
5618 ret = PTR_ERR(trans);
5619 goto out_unlock;
5620 }
5622 spin_lock(&fs_info->super_lock);
5623 strcpy(super_block->label, label);
5624 spin_unlock(&fs_info->super_lock);
5625 ret = btrfs_commit_transaction(trans);
5627 out_unlock:
5628 mnt_drop_write_file(file);
5629 return ret;
5630 }
5632 #define INIT_FEATURE_FLAGS(suffix) \
5633 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5634 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5635 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5637 int btrfs_ioctl_get_supported_features(void __user *arg)
5638 {
5639 static const struct btrfs_ioctl_feature_flags features[3] = {
5640 INIT_FEATURE_FLAGS(SUPP),
5641 INIT_FEATURE_FLAGS(SAFE_SET),
5642 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5643 };
5645 if (copy_to_user(arg, &features, sizeof(features)))
5646 return -EFAULT;
5648 return 0;
5649 }
5651 static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5652 {
5653 struct inode *inode = file_inode(file);
5654 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5655 struct btrfs_super_block *super_block = fs_info->super_copy;
5656 struct btrfs_ioctl_feature_flags features;
5658 features.compat_flags = btrfs_super_compat_flags(super_block);
5659 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5660 features.incompat_flags = btrfs_super_incompat_flags(super_block);
5662 if (copy_to_user(arg, &features, sizeof(features)))
5663 return -EFAULT;
5665 return 0;
5666 }
5668 static int check_feature_bits(struct btrfs_fs_info *fs_info,
5669 enum btrfs_feature_set set,
5670 u64 change_mask, u64 flags, u64 supported_flags,
5671 u64 safe_set, u64 safe_clear)
5672 {
5673 const char *type = btrfs_feature_set_names[set];
5674 char *names;
5675 u64 disallowed, unsupported;
5676 u64 set_mask = flags & change_mask;
5677 u64 clear_mask = ~flags & change_mask;
5679 unsupported = set_mask & ~supported_flags;
5680 if (unsupported) {
5681 names = btrfs_printable_features(set, unsupported);
5682 if (names) {
5683 btrfs_warn(fs_info,
5684 "this kernel does not support the %s feature bit%s",
5685 names, strchr(names, ',') ? "s" : "");
5686 kfree(names);
5687 } else
5688 btrfs_warn(fs_info,
5689 "this kernel does not support %s bits 0x%llx",
5690 type, unsupported);
5691 return -EOPNOTSUPP;
5692 }
5694 disallowed = set_mask & ~safe_set;
5695 if (disallowed) {
5696 names = btrfs_printable_features(set, disallowed);
5697 if (names) {
5698 btrfs_warn(fs_info,
5699 "can't set the %s feature bit%s while mounted",
5700 names, strchr(names, ',') ? "s" : "");
5701 kfree(names);
5702 } else
5703 btrfs_warn(fs_info,
5704 "can't set %s bits 0x%llx while mounted",
5705 type, disallowed);
5706 return -EPERM;
5707 }
5709 disallowed = clear_mask & ~safe_clear;
5710 if (disallowed) {
5711 names = btrfs_printable_features(set, disallowed);
5712 if (names) {
5713 btrfs_warn(fs_info,
5714 "can't clear the %s feature bit%s while mounted",
5715 names, strchr(names, ',') ? "s" : "");
5716 kfree(names);
5717 } else
5718 btrfs_warn(fs_info,
5719 "can't clear %s bits 0x%llx while mounted",
5720 type, disallowed);
5721 return -EPERM;
5722 }
5724 return 0;
5725 }
5727 #define check_feature(fs_info, change_mask, flags, mask_base) \
5728 check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags, \
5729 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
5730 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
5731 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5733 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5734 {
5735 struct inode *inode = file_inode(file);
5736 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5737 struct btrfs_root *root = BTRFS_I(inode)->root;
5738 struct btrfs_super_block *super_block = fs_info->super_copy;
5739 struct btrfs_ioctl_feature_flags flags[2];
5740 struct btrfs_trans_handle *trans;
5741 u64 newflags;
5742 int ret;
5744 if (!capable(CAP_SYS_ADMIN))
5745 return -EPERM;
5747 if (copy_from_user(flags, arg, sizeof(flags)))
5748 return -EFAULT;
5750 /* Nothing to do */
5751 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5752 !flags[0].incompat_flags)
5753 return 0;
5755 ret = check_feature(fs_info, flags[0].compat_flags,
5756 flags[1].compat_flags, COMPAT);
5757 if (ret)
5758 return ret;
5760 ret = check_feature(fs_info, flags[0].compat_ro_flags,
5761 flags[1].compat_ro_flags, COMPAT_RO);
5762 if (ret)
5763 return ret;
5765 ret = check_feature(fs_info, flags[0].incompat_flags,
5766 flags[1].incompat_flags, INCOMPAT);
5767 if (ret)
5768 return ret;
5770 ret = mnt_want_write_file(file);
5771 if (ret)
5772 return ret;
5774 trans = btrfs_start_transaction(root, 0);
5775 if (IS_ERR(trans)) {
5776 ret = PTR_ERR(trans);
5777 goto out_drop_write;
5778 }
5780 spin_lock(&fs_info->super_lock);
5781 newflags = btrfs_super_compat_flags(super_block);
5782 newflags |= flags[0].compat_flags & flags[1].compat_flags;
5783 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5784 btrfs_set_super_compat_flags(super_block, newflags);
5786 newflags = btrfs_super_compat_ro_flags(super_block);
5787 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5788 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5789 btrfs_set_super_compat_ro_flags(super_block, newflags);
5791 newflags = btrfs_super_incompat_flags(super_block);
5792 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5793 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5794 btrfs_set_super_incompat_flags(super_block, newflags);
5795 spin_unlock(&fs_info->super_lock);
5797 ret = btrfs_commit_transaction(trans);
5798 out_drop_write:
5799 mnt_drop_write_file(file);
5801 return ret;
5802 }
5804 static int _btrfs_ioctl_send(struct file *file, void __user *argp, bool compat)
5805 {
5806 struct btrfs_ioctl_send_args *arg;
5807 int ret;
5809 if (compat) {
5810 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
5811 struct btrfs_ioctl_send_args_32 args32;
5813 ret = copy_from_user(&args32, argp, sizeof(args32));
5814 if (ret)
5815 return -EFAULT;
5816 arg = kzalloc(sizeof(*arg), GFP_KERNEL);
5817 if (!arg)
5818 return -ENOMEM;
5819 arg->send_fd = args32.send_fd;
5820 arg->clone_sources_count = args32.clone_sources_count;
5821 arg->clone_sources = compat_ptr(args32.clone_sources);
5822 arg->parent_root = args32.parent_root;
5823 arg->flags = args32.flags;
5824 memcpy(arg->reserved, args32.reserved,
5825 sizeof(args32.reserved));
5826 #else
5827 return -ENOTTY;
5828 #endif
5829 } else {
5830 arg = memdup_user(argp, sizeof(*arg));
5831 if (IS_ERR(arg))
5832 return PTR_ERR(arg);
5833 }
5834 ret = btrfs_ioctl_send(file, arg);
5835 kfree(arg);
5836 return ret;
5837 }
5839 long btrfs_ioctl(struct file *file, unsigned int
5840 cmd, unsigned long arg)
5841 {
5842 struct inode *inode = file_inode(file);
5843 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5844 struct btrfs_root *root = BTRFS_I(inode)->root;
5845 void __user *argp = (void __user *)arg;
5847 switch (cmd) {
5848 case FS_IOC_GETFLAGS:
5849 return btrfs_ioctl_getflags(file, argp);
5850 case FS_IOC_SETFLAGS:
5851 return btrfs_ioctl_setflags(file, argp);
5852 case FS_IOC_GETVERSION:
5853 return btrfs_ioctl_getversion(file, argp);
5854 case FITRIM:
5855 return btrfs_ioctl_fitrim(file, argp);
5856 case BTRFS_IOC_SNAP_CREATE:
5857 return btrfs_ioctl_snap_create(file, argp, 0);
5858 case BTRFS_IOC_SNAP_CREATE_V2:
5859 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5860 case BTRFS_IOC_SUBVOL_CREATE:
5861 return btrfs_ioctl_snap_create(file, argp, 1);
5862 case BTRFS_IOC_SUBVOL_CREATE_V2:
5863 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5864 case BTRFS_IOC_SNAP_DESTROY:
5865 return btrfs_ioctl_snap_destroy(file, argp);
5866 case BTRFS_IOC_SUBVOL_GETFLAGS:
5867 return btrfs_ioctl_subvol_getflags(file, argp);
5868 case BTRFS_IOC_SUBVOL_SETFLAGS:
5869 return btrfs_ioctl_subvol_setflags(file, argp);
5870 case BTRFS_IOC_DEFAULT_SUBVOL:
5871 return btrfs_ioctl_default_subvol(file, argp);
5872 case BTRFS_IOC_DEFRAG:
5873 return btrfs_ioctl_defrag(file, NULL);
5874 case BTRFS_IOC_DEFRAG_RANGE:
5875 return btrfs_ioctl_defrag(file, argp);
5876 case BTRFS_IOC_RESIZE:
5877 return btrfs_ioctl_resize(file, argp);
5878 case BTRFS_IOC_ADD_DEV:
5879 return btrfs_ioctl_add_dev(fs_info, argp);
5880 case BTRFS_IOC_RM_DEV:
5881 return btrfs_ioctl_rm_dev(file, argp);
5882 case BTRFS_IOC_RM_DEV_V2:
5883 return btrfs_ioctl_rm_dev_v2(file, argp);
5884 case BTRFS_IOC_FS_INFO:
5885 return btrfs_ioctl_fs_info(fs_info, argp);
5886 case BTRFS_IOC_DEV_INFO:
5887 return btrfs_ioctl_dev_info(fs_info, argp);
5888 case BTRFS_IOC_BALANCE:
5889 return btrfs_ioctl_balance(file, NULL);
5890 case BTRFS_IOC_TREE_SEARCH:
5891 return btrfs_ioctl_tree_search(file, argp);
5892 case BTRFS_IOC_TREE_SEARCH_V2:
5893 return btrfs_ioctl_tree_search_v2(file, argp);
5894 case BTRFS_IOC_INO_LOOKUP:
5895 return btrfs_ioctl_ino_lookup(file, argp);
5896 case BTRFS_IOC_INO_PATHS:
5897 return btrfs_ioctl_ino_to_path(root, argp);
5898 case BTRFS_IOC_LOGICAL_INO:
5899 return btrfs_ioctl_logical_to_ino(fs_info, argp, 1);
5900 case BTRFS_IOC_LOGICAL_INO_V2:
5901 return btrfs_ioctl_logical_to_ino(fs_info, argp, 2);
5902 case BTRFS_IOC_SPACE_INFO:
5903 return btrfs_ioctl_space_info(fs_info, argp);
5904 case BTRFS_IOC_SYNC: {
5905 int ret;
5907 ret = btrfs_start_delalloc_roots(fs_info, -1);
5908 if (ret)
5909 return ret;
5910 ret = btrfs_sync_fs(inode->i_sb, 1);
5911 /*
5912 * The transaction thread may want to do more work,
5913 * namely it pokes the cleaner kthread that will start
5914 * processing uncleaned subvols.
5915 */
5916 wake_up_process(fs_info->transaction_kthread);
5917 return ret;
5918 }
5919 case BTRFS_IOC_START_SYNC:
5920 return btrfs_ioctl_start_sync(root, argp);
5921 case BTRFS_IOC_WAIT_SYNC:
5922 return btrfs_ioctl_wait_sync(fs_info, argp);
5923 case BTRFS_IOC_SCRUB:
5924 return btrfs_ioctl_scrub(file, argp);
5925 case BTRFS_IOC_SCRUB_CANCEL:
5926 return btrfs_ioctl_scrub_cancel(fs_info);
5927 case BTRFS_IOC_SCRUB_PROGRESS:
5928 return btrfs_ioctl_scrub_progress(fs_info, argp);
5929 case BTRFS_IOC_BALANCE_V2:
5930 return btrfs_ioctl_balance(file, argp);
5931 case BTRFS_IOC_BALANCE_CTL:
5932 return btrfs_ioctl_balance_ctl(fs_info, arg);
5933 case BTRFS_IOC_BALANCE_PROGRESS:
5934 return btrfs_ioctl_balance_progress(fs_info, argp);
5935 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5936 return btrfs_ioctl_set_received_subvol(file, argp);
5937 #ifdef CONFIG_64BIT
5938 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5939 return btrfs_ioctl_set_received_subvol_32(file, argp);
5940 #endif
5941 case BTRFS_IOC_SEND:
5942 return _btrfs_ioctl_send(file, argp, false);
5943 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
5944 case BTRFS_IOC_SEND_32:
5945 return _btrfs_ioctl_send(file, argp, true);
5946 #endif
5947 case BTRFS_IOC_GET_DEV_STATS:
5948 return btrfs_ioctl_get_dev_stats(fs_info, argp);
5949 case BTRFS_IOC_QUOTA_CTL:
5950 return btrfs_ioctl_quota_ctl(file, argp);
5951 case BTRFS_IOC_QGROUP_ASSIGN:
5952 return btrfs_ioctl_qgroup_assign(file, argp);
5953 case BTRFS_IOC_QGROUP_CREATE:
5954 return btrfs_ioctl_qgroup_create(file, argp);
5955 case BTRFS_IOC_QGROUP_LIMIT:
5956 return btrfs_ioctl_qgroup_limit(file, argp);
5957 case BTRFS_IOC_QUOTA_RESCAN:
5958 return btrfs_ioctl_quota_rescan(file, argp);
5959 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5960 return btrfs_ioctl_quota_rescan_status(file, argp);
5961 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5962 return btrfs_ioctl_quota_rescan_wait(file, argp);
5963 case BTRFS_IOC_DEV_REPLACE:
5964 return btrfs_ioctl_dev_replace(fs_info, argp);
5965 case BTRFS_IOC_GET_FSLABEL:
5966 return btrfs_ioctl_get_fslabel(file, argp);
5967 case BTRFS_IOC_SET_FSLABEL:
5968 return btrfs_ioctl_set_fslabel(file, argp);
5969 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5970 return btrfs_ioctl_get_supported_features(argp);
5971 case BTRFS_IOC_GET_FEATURES:
5972 return btrfs_ioctl_get_features(file, argp);
5973 case BTRFS_IOC_SET_FEATURES:
5974 return btrfs_ioctl_set_features(file, argp);
5975 case FS_IOC_FSGETXATTR:
5976 return btrfs_ioctl_fsgetxattr(file, argp);
5977 case FS_IOC_FSSETXATTR:
5978 return btrfs_ioctl_fssetxattr(file, argp);
5979 case BTRFS_IOC_GET_SUBVOL_INFO:
5980 return btrfs_ioctl_get_subvol_info(file, argp);
5981 case BTRFS_IOC_GET_SUBVOL_ROOTREF:
5982 return btrfs_ioctl_get_subvol_rootref(file, argp);
5983 case BTRFS_IOC_INO_LOOKUP_USER:
5984 return btrfs_ioctl_ino_lookup_user(file, argp);
5985 }
5987 return -ENOTTY;
5988 }
5990 #ifdef CONFIG_COMPAT
5991 long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
5992 {
5993 /*
5994 * These all access 32-bit values anyway so no further
5995 * handling is necessary.
5996 */
5997 switch (cmd) {
5998 case FS_IOC32_GETFLAGS:
5999 cmd = FS_IOC_GETFLAGS;
6000 break;
6001 case FS_IOC32_SETFLAGS:
6002 cmd = FS_IOC_SETFLAGS;
6003 break;
6004 case FS_IOC32_GETVERSION:
6005 cmd = FS_IOC_GETVERSION;
6006 break;
6007 }
6009 return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
6010 }
6011 #endif