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Merge tag 'compress-3.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh...
[deliverable/linux.git] / fs / btrfs / ioctl.c
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19 #include <linux/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.h>
23 #include <linux/fs.h>
24 #include <linux/fsnotify.h>
25 #include <linux/pagemap.h>
26 #include <linux/highmem.h>
27 #include <linux/time.h>
28 #include <linux/init.h>
29 #include <linux/string.h>
30 #include <linux/backing-dev.h>
31 #include <linux/mount.h>
32 #include <linux/mpage.h>
33 #include <linux/namei.h>
34 #include <linux/swap.h>
35 #include <linux/writeback.h>
36 #include <linux/statfs.h>
37 #include <linux/compat.h>
38 #include <linux/bit_spinlock.h>
39 #include <linux/security.h>
40 #include <linux/xattr.h>
41 #include <linux/vmalloc.h>
42 #include <linux/slab.h>
43 #include <linux/blkdev.h>
44 #include <linux/uuid.h>
45 #include <linux/btrfs.h>
46 #include <linux/uaccess.h>
47 #include "ctree.h"
48 #include "disk-io.h"
49 #include "transaction.h"
50 #include "btrfs_inode.h"
51 #include "print-tree.h"
52 #include "volumes.h"
53 #include "locking.h"
54 #include "inode-map.h"
55 #include "backref.h"
56 #include "rcu-string.h"
57 #include "send.h"
58 #include "dev-replace.h"
59 #include "props.h"
60 #include "sysfs.h"
61 #include "qgroup.h"
62
63 #ifdef CONFIG_64BIT
64 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
65 * structures are incorrect, as the timespec structure from userspace
66 * is 4 bytes too small. We define these alternatives here to teach
67 * the kernel about the 32-bit struct packing.
68 */
69 struct btrfs_ioctl_timespec_32 {
70 __u64 sec;
71 __u32 nsec;
72 } __attribute__ ((__packed__));
73
74 struct btrfs_ioctl_received_subvol_args_32 {
75 char uuid[BTRFS_UUID_SIZE]; /* in */
76 __u64 stransid; /* in */
77 __u64 rtransid; /* out */
78 struct btrfs_ioctl_timespec_32 stime; /* in */
79 struct btrfs_ioctl_timespec_32 rtime; /* out */
80 __u64 flags; /* in */
81 __u64 reserved[16]; /* in */
82 } __attribute__ ((__packed__));
83
84 #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
85 struct btrfs_ioctl_received_subvol_args_32)
86 #endif
87
88
89 static int btrfs_clone(struct inode *src, struct inode *inode,
90 u64 off, u64 olen, u64 olen_aligned, u64 destoff);
91
92 /* Mask out flags that are inappropriate for the given type of inode. */
93 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
94 {
95 if (S_ISDIR(mode))
96 return flags;
97 else if (S_ISREG(mode))
98 return flags & ~FS_DIRSYNC_FL;
99 else
100 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
101 }
102
103 /*
104 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
105 */
106 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
107 {
108 unsigned int iflags = 0;
109
110 if (flags & BTRFS_INODE_SYNC)
111 iflags |= FS_SYNC_FL;
112 if (flags & BTRFS_INODE_IMMUTABLE)
113 iflags |= FS_IMMUTABLE_FL;
114 if (flags & BTRFS_INODE_APPEND)
115 iflags |= FS_APPEND_FL;
116 if (flags & BTRFS_INODE_NODUMP)
117 iflags |= FS_NODUMP_FL;
118 if (flags & BTRFS_INODE_NOATIME)
119 iflags |= FS_NOATIME_FL;
120 if (flags & BTRFS_INODE_DIRSYNC)
121 iflags |= FS_DIRSYNC_FL;
122 if (flags & BTRFS_INODE_NODATACOW)
123 iflags |= FS_NOCOW_FL;
124
125 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
126 iflags |= FS_COMPR_FL;
127 else if (flags & BTRFS_INODE_NOCOMPRESS)
128 iflags |= FS_NOCOMP_FL;
129
130 return iflags;
131 }
132
133 /*
134 * Update inode->i_flags based on the btrfs internal flags.
135 */
136 void btrfs_update_iflags(struct inode *inode)
137 {
138 struct btrfs_inode *ip = BTRFS_I(inode);
139
140 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
141
142 if (ip->flags & BTRFS_INODE_SYNC)
143 inode->i_flags |= S_SYNC;
144 if (ip->flags & BTRFS_INODE_IMMUTABLE)
145 inode->i_flags |= S_IMMUTABLE;
146 if (ip->flags & BTRFS_INODE_APPEND)
147 inode->i_flags |= S_APPEND;
148 if (ip->flags & BTRFS_INODE_NOATIME)
149 inode->i_flags |= S_NOATIME;
150 if (ip->flags & BTRFS_INODE_DIRSYNC)
151 inode->i_flags |= S_DIRSYNC;
152 }
153
154 /*
155 * Inherit flags from the parent inode.
156 *
157 * Currently only the compression flags and the cow flags are inherited.
158 */
159 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
160 {
161 unsigned int flags;
162
163 if (!dir)
164 return;
165
166 flags = BTRFS_I(dir)->flags;
167
168 if (flags & BTRFS_INODE_NOCOMPRESS) {
169 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
170 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
171 } else if (flags & BTRFS_INODE_COMPRESS) {
172 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
173 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
174 }
175
176 if (flags & BTRFS_INODE_NODATACOW) {
177 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
178 if (S_ISREG(inode->i_mode))
179 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
180 }
181
182 btrfs_update_iflags(inode);
183 }
184
185 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
186 {
187 struct btrfs_inode *ip = BTRFS_I(file_inode(file));
188 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
189
190 if (copy_to_user(arg, &flags, sizeof(flags)))
191 return -EFAULT;
192 return 0;
193 }
194
195 static int check_flags(unsigned int flags)
196 {
197 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
198 FS_NOATIME_FL | FS_NODUMP_FL | \
199 FS_SYNC_FL | FS_DIRSYNC_FL | \
200 FS_NOCOMP_FL | FS_COMPR_FL |
201 FS_NOCOW_FL))
202 return -EOPNOTSUPP;
203
204 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
205 return -EINVAL;
206
207 return 0;
208 }
209
210 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
211 {
212 struct inode *inode = file_inode(file);
213 struct btrfs_inode *ip = BTRFS_I(inode);
214 struct btrfs_root *root = ip->root;
215 struct btrfs_trans_handle *trans;
216 unsigned int flags, oldflags;
217 int ret;
218 u64 ip_oldflags;
219 unsigned int i_oldflags;
220 umode_t mode;
221
222 if (!inode_owner_or_capable(inode))
223 return -EPERM;
224
225 if (btrfs_root_readonly(root))
226 return -EROFS;
227
228 if (copy_from_user(&flags, arg, sizeof(flags)))
229 return -EFAULT;
230
231 ret = check_flags(flags);
232 if (ret)
233 return ret;
234
235 ret = mnt_want_write_file(file);
236 if (ret)
237 return ret;
238
239 mutex_lock(&inode->i_mutex);
240
241 ip_oldflags = ip->flags;
242 i_oldflags = inode->i_flags;
243 mode = inode->i_mode;
244
245 flags = btrfs_mask_flags(inode->i_mode, flags);
246 oldflags = btrfs_flags_to_ioctl(ip->flags);
247 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
248 if (!capable(CAP_LINUX_IMMUTABLE)) {
249 ret = -EPERM;
250 goto out_unlock;
251 }
252 }
253
254 if (flags & FS_SYNC_FL)
255 ip->flags |= BTRFS_INODE_SYNC;
256 else
257 ip->flags &= ~BTRFS_INODE_SYNC;
258 if (flags & FS_IMMUTABLE_FL)
259 ip->flags |= BTRFS_INODE_IMMUTABLE;
260 else
261 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
262 if (flags & FS_APPEND_FL)
263 ip->flags |= BTRFS_INODE_APPEND;
264 else
265 ip->flags &= ~BTRFS_INODE_APPEND;
266 if (flags & FS_NODUMP_FL)
267 ip->flags |= BTRFS_INODE_NODUMP;
268 else
269 ip->flags &= ~BTRFS_INODE_NODUMP;
270 if (flags & FS_NOATIME_FL)
271 ip->flags |= BTRFS_INODE_NOATIME;
272 else
273 ip->flags &= ~BTRFS_INODE_NOATIME;
274 if (flags & FS_DIRSYNC_FL)
275 ip->flags |= BTRFS_INODE_DIRSYNC;
276 else
277 ip->flags &= ~BTRFS_INODE_DIRSYNC;
278 if (flags & FS_NOCOW_FL) {
279 if (S_ISREG(mode)) {
280 /*
281 * It's safe to turn csums off here, no extents exist.
282 * Otherwise we want the flag to reflect the real COW
283 * status of the file and will not set it.
284 */
285 if (inode->i_size == 0)
286 ip->flags |= BTRFS_INODE_NODATACOW
287 | BTRFS_INODE_NODATASUM;
288 } else {
289 ip->flags |= BTRFS_INODE_NODATACOW;
290 }
291 } else {
292 /*
293 * Revert back under same assuptions as above
294 */
295 if (S_ISREG(mode)) {
296 if (inode->i_size == 0)
297 ip->flags &= ~(BTRFS_INODE_NODATACOW
298 | BTRFS_INODE_NODATASUM);
299 } else {
300 ip->flags &= ~BTRFS_INODE_NODATACOW;
301 }
302 }
303
304 /*
305 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
306 * flag may be changed automatically if compression code won't make
307 * things smaller.
308 */
309 if (flags & FS_NOCOMP_FL) {
310 ip->flags &= ~BTRFS_INODE_COMPRESS;
311 ip->flags |= BTRFS_INODE_NOCOMPRESS;
312
313 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
314 if (ret && ret != -ENODATA)
315 goto out_drop;
316 } else if (flags & FS_COMPR_FL) {
317 const char *comp;
318
319 ip->flags |= BTRFS_INODE_COMPRESS;
320 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
321
322 if (root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
323 comp = "lzo";
324 else
325 comp = "zlib";
326 ret = btrfs_set_prop(inode, "btrfs.compression",
327 comp, strlen(comp), 0);
328 if (ret)
329 goto out_drop;
330
331 } else {
332 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
333 }
334
335 trans = btrfs_start_transaction(root, 1);
336 if (IS_ERR(trans)) {
337 ret = PTR_ERR(trans);
338 goto out_drop;
339 }
340
341 btrfs_update_iflags(inode);
342 inode_inc_iversion(inode);
343 inode->i_ctime = CURRENT_TIME;
344 ret = btrfs_update_inode(trans, root, inode);
345
346 btrfs_end_transaction(trans, root);
347 out_drop:
348 if (ret) {
349 ip->flags = ip_oldflags;
350 inode->i_flags = i_oldflags;
351 }
352
353 out_unlock:
354 mutex_unlock(&inode->i_mutex);
355 mnt_drop_write_file(file);
356 return ret;
357 }
358
359 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
360 {
361 struct inode *inode = file_inode(file);
362
363 return put_user(inode->i_generation, arg);
364 }
365
366 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
367 {
368 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
369 struct btrfs_device *device;
370 struct request_queue *q;
371 struct fstrim_range range;
372 u64 minlen = ULLONG_MAX;
373 u64 num_devices = 0;
374 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
375 int ret;
376
377 if (!capable(CAP_SYS_ADMIN))
378 return -EPERM;
379
380 rcu_read_lock();
381 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
382 dev_list) {
383 if (!device->bdev)
384 continue;
385 q = bdev_get_queue(device->bdev);
386 if (blk_queue_discard(q)) {
387 num_devices++;
388 minlen = min((u64)q->limits.discard_granularity,
389 minlen);
390 }
391 }
392 rcu_read_unlock();
393
394 if (!num_devices)
395 return -EOPNOTSUPP;
396 if (copy_from_user(&range, arg, sizeof(range)))
397 return -EFAULT;
398 if (range.start > total_bytes ||
399 range.len < fs_info->sb->s_blocksize)
400 return -EINVAL;
401
402 range.len = min(range.len, total_bytes - range.start);
403 range.minlen = max(range.minlen, minlen);
404 ret = btrfs_trim_fs(fs_info->tree_root, &range);
405 if (ret < 0)
406 return ret;
407
408 if (copy_to_user(arg, &range, sizeof(range)))
409 return -EFAULT;
410
411 return 0;
412 }
413
414 int btrfs_is_empty_uuid(u8 *uuid)
415 {
416 int i;
417
418 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
419 if (uuid[i])
420 return 0;
421 }
422 return 1;
423 }
424
425 static noinline int create_subvol(struct inode *dir,
426 struct dentry *dentry,
427 char *name, int namelen,
428 u64 *async_transid,
429 struct btrfs_qgroup_inherit *inherit)
430 {
431 struct btrfs_trans_handle *trans;
432 struct btrfs_key key;
433 struct btrfs_root_item root_item;
434 struct btrfs_inode_item *inode_item;
435 struct extent_buffer *leaf;
436 struct btrfs_root *root = BTRFS_I(dir)->root;
437 struct btrfs_root *new_root;
438 struct btrfs_block_rsv block_rsv;
439 struct timespec cur_time = CURRENT_TIME;
440 struct inode *inode;
441 int ret;
442 int err;
443 u64 objectid;
444 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
445 u64 index = 0;
446 u64 qgroup_reserved;
447 uuid_le new_uuid;
448
449 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
450 if (ret)
451 return ret;
452
453 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
454 /*
455 * The same as the snapshot creation, please see the comment
456 * of create_snapshot().
457 */
458 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
459 8, &qgroup_reserved, false);
460 if (ret)
461 return ret;
462
463 trans = btrfs_start_transaction(root, 0);
464 if (IS_ERR(trans)) {
465 ret = PTR_ERR(trans);
466 btrfs_subvolume_release_metadata(root, &block_rsv,
467 qgroup_reserved);
468 return ret;
469 }
470 trans->block_rsv = &block_rsv;
471 trans->bytes_reserved = block_rsv.size;
472
473 ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
474 if (ret)
475 goto fail;
476
477 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
478 0, objectid, NULL, 0, 0, 0);
479 if (IS_ERR(leaf)) {
480 ret = PTR_ERR(leaf);
481 goto fail;
482 }
483
484 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
485 btrfs_set_header_bytenr(leaf, leaf->start);
486 btrfs_set_header_generation(leaf, trans->transid);
487 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
488 btrfs_set_header_owner(leaf, objectid);
489
490 write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(),
491 BTRFS_FSID_SIZE);
492 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
493 btrfs_header_chunk_tree_uuid(leaf),
494 BTRFS_UUID_SIZE);
495 btrfs_mark_buffer_dirty(leaf);
496
497 memset(&root_item, 0, sizeof(root_item));
498
499 inode_item = &root_item.inode;
500 btrfs_set_stack_inode_generation(inode_item, 1);
501 btrfs_set_stack_inode_size(inode_item, 3);
502 btrfs_set_stack_inode_nlink(inode_item, 1);
503 btrfs_set_stack_inode_nbytes(inode_item, root->leafsize);
504 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
505
506 btrfs_set_root_flags(&root_item, 0);
507 btrfs_set_root_limit(&root_item, 0);
508 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
509
510 btrfs_set_root_bytenr(&root_item, leaf->start);
511 btrfs_set_root_generation(&root_item, trans->transid);
512 btrfs_set_root_level(&root_item, 0);
513 btrfs_set_root_refs(&root_item, 1);
514 btrfs_set_root_used(&root_item, leaf->len);
515 btrfs_set_root_last_snapshot(&root_item, 0);
516
517 btrfs_set_root_generation_v2(&root_item,
518 btrfs_root_generation(&root_item));
519 uuid_le_gen(&new_uuid);
520 memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
521 btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
522 btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec);
523 root_item.ctime = root_item.otime;
524 btrfs_set_root_ctransid(&root_item, trans->transid);
525 btrfs_set_root_otransid(&root_item, trans->transid);
526
527 btrfs_tree_unlock(leaf);
528 free_extent_buffer(leaf);
529 leaf = NULL;
530
531 btrfs_set_root_dirid(&root_item, new_dirid);
532
533 key.objectid = objectid;
534 key.offset = 0;
535 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
536 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
537 &root_item);
538 if (ret)
539 goto fail;
540
541 key.offset = (u64)-1;
542 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
543 if (IS_ERR(new_root)) {
544 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
545 ret = PTR_ERR(new_root);
546 goto fail;
547 }
548
549 btrfs_record_root_in_trans(trans, new_root);
550
551 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
552 if (ret) {
553 /* We potentially lose an unused inode item here */
554 btrfs_abort_transaction(trans, root, ret);
555 goto fail;
556 }
557
558 /*
559 * insert the directory item
560 */
561 ret = btrfs_set_inode_index(dir, &index);
562 if (ret) {
563 btrfs_abort_transaction(trans, root, ret);
564 goto fail;
565 }
566
567 ret = btrfs_insert_dir_item(trans, root,
568 name, namelen, dir, &key,
569 BTRFS_FT_DIR, index);
570 if (ret) {
571 btrfs_abort_transaction(trans, root, ret);
572 goto fail;
573 }
574
575 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
576 ret = btrfs_update_inode(trans, root, dir);
577 BUG_ON(ret);
578
579 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
580 objectid, root->root_key.objectid,
581 btrfs_ino(dir), index, name, namelen);
582 BUG_ON(ret);
583
584 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
585 root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
586 objectid);
587 if (ret)
588 btrfs_abort_transaction(trans, root, ret);
589
590 fail:
591 trans->block_rsv = NULL;
592 trans->bytes_reserved = 0;
593 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
594
595 if (async_transid) {
596 *async_transid = trans->transid;
597 err = btrfs_commit_transaction_async(trans, root, 1);
598 if (err)
599 err = btrfs_commit_transaction(trans, root);
600 } else {
601 err = btrfs_commit_transaction(trans, root);
602 }
603 if (err && !ret)
604 ret = err;
605
606 if (!ret) {
607 inode = btrfs_lookup_dentry(dir, dentry);
608 if (IS_ERR(inode))
609 return PTR_ERR(inode);
610 d_instantiate(dentry, inode);
611 }
612 return ret;
613 }
614
615 static void btrfs_wait_nocow_write(struct btrfs_root *root)
616 {
617 s64 writers;
618 DEFINE_WAIT(wait);
619
620 do {
621 prepare_to_wait(&root->subv_writers->wait, &wait,
622 TASK_UNINTERRUPTIBLE);
623
624 writers = percpu_counter_sum(&root->subv_writers->counter);
625 if (writers)
626 schedule();
627
628 finish_wait(&root->subv_writers->wait, &wait);
629 } while (writers);
630 }
631
632 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
633 struct dentry *dentry, char *name, int namelen,
634 u64 *async_transid, bool readonly,
635 struct btrfs_qgroup_inherit *inherit)
636 {
637 struct inode *inode;
638 struct btrfs_pending_snapshot *pending_snapshot;
639 struct btrfs_trans_handle *trans;
640 int ret;
641
642 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
643 return -EINVAL;
644
645 atomic_inc(&root->will_be_snapshoted);
646 smp_mb__after_atomic();
647 btrfs_wait_nocow_write(root);
648
649 ret = btrfs_start_delalloc_inodes(root, 0);
650 if (ret)
651 goto out;
652
653 btrfs_wait_ordered_extents(root, -1);
654
655 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
656 if (!pending_snapshot) {
657 ret = -ENOMEM;
658 goto out;
659 }
660
661 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
662 BTRFS_BLOCK_RSV_TEMP);
663 /*
664 * 1 - parent dir inode
665 * 2 - dir entries
666 * 1 - root item
667 * 2 - root ref/backref
668 * 1 - root of snapshot
669 * 1 - UUID item
670 */
671 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
672 &pending_snapshot->block_rsv, 8,
673 &pending_snapshot->qgroup_reserved,
674 false);
675 if (ret)
676 goto free;
677
678 pending_snapshot->dentry = dentry;
679 pending_snapshot->root = root;
680 pending_snapshot->readonly = readonly;
681 pending_snapshot->dir = dir;
682 pending_snapshot->inherit = inherit;
683
684 trans = btrfs_start_transaction(root, 0);
685 if (IS_ERR(trans)) {
686 ret = PTR_ERR(trans);
687 goto fail;
688 }
689
690 spin_lock(&root->fs_info->trans_lock);
691 list_add(&pending_snapshot->list,
692 &trans->transaction->pending_snapshots);
693 spin_unlock(&root->fs_info->trans_lock);
694 if (async_transid) {
695 *async_transid = trans->transid;
696 ret = btrfs_commit_transaction_async(trans,
697 root->fs_info->extent_root, 1);
698 if (ret)
699 ret = btrfs_commit_transaction(trans, root);
700 } else {
701 ret = btrfs_commit_transaction(trans,
702 root->fs_info->extent_root);
703 }
704 if (ret)
705 goto fail;
706
707 ret = pending_snapshot->error;
708 if (ret)
709 goto fail;
710
711 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
712 if (ret)
713 goto fail;
714
715 /*
716 * If orphan cleanup did remove any orphans, it means the tree was
717 * modified and therefore the commit root is not the same as the
718 * current root anymore. This is a problem, because send uses the
719 * commit root and therefore can see inode items that don't exist
720 * in the current root anymore, and for example make calls to
721 * btrfs_iget, which will do tree lookups based on the current root
722 * and not on the commit root. Those lookups will fail, returning a
723 * -ESTALE error, and making send fail with that error. So make sure
724 * a send does not see any orphans we have just removed, and that it
725 * will see the same inodes regardless of whether a transaction
726 * commit happened before it started (meaning that the commit root
727 * will be the same as the current root) or not.
728 */
729 if (readonly && pending_snapshot->snap->node !=
730 pending_snapshot->snap->commit_root) {
731 trans = btrfs_join_transaction(pending_snapshot->snap);
732 if (IS_ERR(trans) && PTR_ERR(trans) != -ENOENT) {
733 ret = PTR_ERR(trans);
734 goto fail;
735 }
736 if (!IS_ERR(trans)) {
737 ret = btrfs_commit_transaction(trans,
738 pending_snapshot->snap);
739 if (ret)
740 goto fail;
741 }
742 }
743
744 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
745 if (IS_ERR(inode)) {
746 ret = PTR_ERR(inode);
747 goto fail;
748 }
749
750 d_instantiate(dentry, inode);
751 ret = 0;
752 fail:
753 btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
754 &pending_snapshot->block_rsv,
755 pending_snapshot->qgroup_reserved);
756 free:
757 kfree(pending_snapshot);
758 out:
759 atomic_dec(&root->will_be_snapshoted);
760 return ret;
761 }
762
763 /* copy of check_sticky in fs/namei.c()
764 * It's inline, so penalty for filesystems that don't use sticky bit is
765 * minimal.
766 */
767 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
768 {
769 kuid_t fsuid = current_fsuid();
770
771 if (!(dir->i_mode & S_ISVTX))
772 return 0;
773 if (uid_eq(inode->i_uid, fsuid))
774 return 0;
775 if (uid_eq(dir->i_uid, fsuid))
776 return 0;
777 return !capable(CAP_FOWNER);
778 }
779
780 /* copy of may_delete in fs/namei.c()
781 * Check whether we can remove a link victim from directory dir, check
782 * whether the type of victim is right.
783 * 1. We can't do it if dir is read-only (done in permission())
784 * 2. We should have write and exec permissions on dir
785 * 3. We can't remove anything from append-only dir
786 * 4. We can't do anything with immutable dir (done in permission())
787 * 5. If the sticky bit on dir is set we should either
788 * a. be owner of dir, or
789 * b. be owner of victim, or
790 * c. have CAP_FOWNER capability
791 * 6. If the victim is append-only or immutable we can't do antyhing with
792 * links pointing to it.
793 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
794 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
795 * 9. We can't remove a root or mountpoint.
796 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
797 * nfs_async_unlink().
798 */
799
800 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
801 {
802 int error;
803
804 if (!victim->d_inode)
805 return -ENOENT;
806
807 BUG_ON(victim->d_parent->d_inode != dir);
808 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
809
810 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
811 if (error)
812 return error;
813 if (IS_APPEND(dir))
814 return -EPERM;
815 if (btrfs_check_sticky(dir, victim->d_inode)||
816 IS_APPEND(victim->d_inode)||
817 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
818 return -EPERM;
819 if (isdir) {
820 if (!S_ISDIR(victim->d_inode->i_mode))
821 return -ENOTDIR;
822 if (IS_ROOT(victim))
823 return -EBUSY;
824 } else if (S_ISDIR(victim->d_inode->i_mode))
825 return -EISDIR;
826 if (IS_DEADDIR(dir))
827 return -ENOENT;
828 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
829 return -EBUSY;
830 return 0;
831 }
832
833 /* copy of may_create in fs/namei.c() */
834 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
835 {
836 if (child->d_inode)
837 return -EEXIST;
838 if (IS_DEADDIR(dir))
839 return -ENOENT;
840 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
841 }
842
843 /*
844 * Create a new subvolume below @parent. This is largely modeled after
845 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
846 * inside this filesystem so it's quite a bit simpler.
847 */
848 static noinline int btrfs_mksubvol(struct path *parent,
849 char *name, int namelen,
850 struct btrfs_root *snap_src,
851 u64 *async_transid, bool readonly,
852 struct btrfs_qgroup_inherit *inherit)
853 {
854 struct inode *dir = parent->dentry->d_inode;
855 struct dentry *dentry;
856 int error;
857
858 error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
859 if (error == -EINTR)
860 return error;
861
862 dentry = lookup_one_len(name, parent->dentry, namelen);
863 error = PTR_ERR(dentry);
864 if (IS_ERR(dentry))
865 goto out_unlock;
866
867 error = -EEXIST;
868 if (dentry->d_inode)
869 goto out_dput;
870
871 error = btrfs_may_create(dir, dentry);
872 if (error)
873 goto out_dput;
874
875 /*
876 * even if this name doesn't exist, we may get hash collisions.
877 * check for them now when we can safely fail
878 */
879 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
880 dir->i_ino, name,
881 namelen);
882 if (error)
883 goto out_dput;
884
885 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
886
887 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
888 goto out_up_read;
889
890 if (snap_src) {
891 error = create_snapshot(snap_src, dir, dentry, name, namelen,
892 async_transid, readonly, inherit);
893 } else {
894 error = create_subvol(dir, dentry, name, namelen,
895 async_transid, inherit);
896 }
897 if (!error)
898 fsnotify_mkdir(dir, dentry);
899 out_up_read:
900 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
901 out_dput:
902 dput(dentry);
903 out_unlock:
904 mutex_unlock(&dir->i_mutex);
905 return error;
906 }
907
908 /*
909 * When we're defragging a range, we don't want to kick it off again
910 * if it is really just waiting for delalloc to send it down.
911 * If we find a nice big extent or delalloc range for the bytes in the
912 * file you want to defrag, we return 0 to let you know to skip this
913 * part of the file
914 */
915 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
916 {
917 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
918 struct extent_map *em = NULL;
919 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
920 u64 end;
921
922 read_lock(&em_tree->lock);
923 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
924 read_unlock(&em_tree->lock);
925
926 if (em) {
927 end = extent_map_end(em);
928 free_extent_map(em);
929 if (end - offset > thresh)
930 return 0;
931 }
932 /* if we already have a nice delalloc here, just stop */
933 thresh /= 2;
934 end = count_range_bits(io_tree, &offset, offset + thresh,
935 thresh, EXTENT_DELALLOC, 1);
936 if (end >= thresh)
937 return 0;
938 return 1;
939 }
940
941 /*
942 * helper function to walk through a file and find extents
943 * newer than a specific transid, and smaller than thresh.
944 *
945 * This is used by the defragging code to find new and small
946 * extents
947 */
948 static int find_new_extents(struct btrfs_root *root,
949 struct inode *inode, u64 newer_than,
950 u64 *off, int thresh)
951 {
952 struct btrfs_path *path;
953 struct btrfs_key min_key;
954 struct extent_buffer *leaf;
955 struct btrfs_file_extent_item *extent;
956 int type;
957 int ret;
958 u64 ino = btrfs_ino(inode);
959
960 path = btrfs_alloc_path();
961 if (!path)
962 return -ENOMEM;
963
964 min_key.objectid = ino;
965 min_key.type = BTRFS_EXTENT_DATA_KEY;
966 min_key.offset = *off;
967
968 while (1) {
969 path->keep_locks = 1;
970 ret = btrfs_search_forward(root, &min_key, path, newer_than);
971 if (ret != 0)
972 goto none;
973 path->keep_locks = 0;
974 btrfs_unlock_up_safe(path, 1);
975 process_slot:
976 if (min_key.objectid != ino)
977 goto none;
978 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
979 goto none;
980
981 leaf = path->nodes[0];
982 extent = btrfs_item_ptr(leaf, path->slots[0],
983 struct btrfs_file_extent_item);
984
985 type = btrfs_file_extent_type(leaf, extent);
986 if (type == BTRFS_FILE_EXTENT_REG &&
987 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
988 check_defrag_in_cache(inode, min_key.offset, thresh)) {
989 *off = min_key.offset;
990 btrfs_free_path(path);
991 return 0;
992 }
993
994 path->slots[0]++;
995 if (path->slots[0] < btrfs_header_nritems(leaf)) {
996 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
997 goto process_slot;
998 }
999
1000 if (min_key.offset == (u64)-1)
1001 goto none;
1002
1003 min_key.offset++;
1004 btrfs_release_path(path);
1005 }
1006 none:
1007 btrfs_free_path(path);
1008 return -ENOENT;
1009 }
1010
1011 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
1012 {
1013 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1014 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1015 struct extent_map *em;
1016 u64 len = PAGE_CACHE_SIZE;
1017
1018 /*
1019 * hopefully we have this extent in the tree already, try without
1020 * the full extent lock
1021 */
1022 read_lock(&em_tree->lock);
1023 em = lookup_extent_mapping(em_tree, start, len);
1024 read_unlock(&em_tree->lock);
1025
1026 if (!em) {
1027 struct extent_state *cached = NULL;
1028 u64 end = start + len - 1;
1029
1030 /* get the big lock and read metadata off disk */
1031 lock_extent_bits(io_tree, start, end, 0, &cached);
1032 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
1033 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
1034
1035 if (IS_ERR(em))
1036 return NULL;
1037 }
1038
1039 return em;
1040 }
1041
1042 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1043 {
1044 struct extent_map *next;
1045 bool ret = true;
1046
1047 /* this is the last extent */
1048 if (em->start + em->len >= i_size_read(inode))
1049 return false;
1050
1051 next = defrag_lookup_extent(inode, em->start + em->len);
1052 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE ||
1053 (em->block_start + em->block_len == next->block_start))
1054 ret = false;
1055
1056 free_extent_map(next);
1057 return ret;
1058 }
1059
1060 static int should_defrag_range(struct inode *inode, u64 start, int thresh,
1061 u64 *last_len, u64 *skip, u64 *defrag_end,
1062 int compress)
1063 {
1064 struct extent_map *em;
1065 int ret = 1;
1066 bool next_mergeable = true;
1067
1068 /*
1069 * make sure that once we start defragging an extent, we keep on
1070 * defragging it
1071 */
1072 if (start < *defrag_end)
1073 return 1;
1074
1075 *skip = 0;
1076
1077 em = defrag_lookup_extent(inode, start);
1078 if (!em)
1079 return 0;
1080
1081 /* this will cover holes, and inline extents */
1082 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1083 ret = 0;
1084 goto out;
1085 }
1086
1087 next_mergeable = defrag_check_next_extent(inode, em);
1088
1089 /*
1090 * we hit a real extent, if it is big or the next extent is not a
1091 * real extent, don't bother defragging it
1092 */
1093 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1094 (em->len >= thresh || !next_mergeable))
1095 ret = 0;
1096 out:
1097 /*
1098 * last_len ends up being a counter of how many bytes we've defragged.
1099 * every time we choose not to defrag an extent, we reset *last_len
1100 * so that the next tiny extent will force a defrag.
1101 *
1102 * The end result of this is that tiny extents before a single big
1103 * extent will force at least part of that big extent to be defragged.
1104 */
1105 if (ret) {
1106 *defrag_end = extent_map_end(em);
1107 } else {
1108 *last_len = 0;
1109 *skip = extent_map_end(em);
1110 *defrag_end = 0;
1111 }
1112
1113 free_extent_map(em);
1114 return ret;
1115 }
1116
1117 /*
1118 * it doesn't do much good to defrag one or two pages
1119 * at a time. This pulls in a nice chunk of pages
1120 * to COW and defrag.
1121 *
1122 * It also makes sure the delalloc code has enough
1123 * dirty data to avoid making new small extents as part
1124 * of the defrag
1125 *
1126 * It's a good idea to start RA on this range
1127 * before calling this.
1128 */
1129 static int cluster_pages_for_defrag(struct inode *inode,
1130 struct page **pages,
1131 unsigned long start_index,
1132 unsigned long num_pages)
1133 {
1134 unsigned long file_end;
1135 u64 isize = i_size_read(inode);
1136 u64 page_start;
1137 u64 page_end;
1138 u64 page_cnt;
1139 int ret;
1140 int i;
1141 int i_done;
1142 struct btrfs_ordered_extent *ordered;
1143 struct extent_state *cached_state = NULL;
1144 struct extent_io_tree *tree;
1145 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1146
1147 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1148 if (!isize || start_index > file_end)
1149 return 0;
1150
1151 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1152
1153 ret = btrfs_delalloc_reserve_space(inode,
1154 page_cnt << PAGE_CACHE_SHIFT);
1155 if (ret)
1156 return ret;
1157 i_done = 0;
1158 tree = &BTRFS_I(inode)->io_tree;
1159
1160 /* step one, lock all the pages */
1161 for (i = 0; i < page_cnt; i++) {
1162 struct page *page;
1163 again:
1164 page = find_or_create_page(inode->i_mapping,
1165 start_index + i, mask);
1166 if (!page)
1167 break;
1168
1169 page_start = page_offset(page);
1170 page_end = page_start + PAGE_CACHE_SIZE - 1;
1171 while (1) {
1172 lock_extent_bits(tree, page_start, page_end,
1173 0, &cached_state);
1174 ordered = btrfs_lookup_ordered_extent(inode,
1175 page_start);
1176 unlock_extent_cached(tree, page_start, page_end,
1177 &cached_state, GFP_NOFS);
1178 if (!ordered)
1179 break;
1180
1181 unlock_page(page);
1182 btrfs_start_ordered_extent(inode, ordered, 1);
1183 btrfs_put_ordered_extent(ordered);
1184 lock_page(page);
1185 /*
1186 * we unlocked the page above, so we need check if
1187 * it was released or not.
1188 */
1189 if (page->mapping != inode->i_mapping) {
1190 unlock_page(page);
1191 page_cache_release(page);
1192 goto again;
1193 }
1194 }
1195
1196 if (!PageUptodate(page)) {
1197 btrfs_readpage(NULL, page);
1198 lock_page(page);
1199 if (!PageUptodate(page)) {
1200 unlock_page(page);
1201 page_cache_release(page);
1202 ret = -EIO;
1203 break;
1204 }
1205 }
1206
1207 if (page->mapping != inode->i_mapping) {
1208 unlock_page(page);
1209 page_cache_release(page);
1210 goto again;
1211 }
1212
1213 pages[i] = page;
1214 i_done++;
1215 }
1216 if (!i_done || ret)
1217 goto out;
1218
1219 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1220 goto out;
1221
1222 /*
1223 * so now we have a nice long stream of locked
1224 * and up to date pages, lets wait on them
1225 */
1226 for (i = 0; i < i_done; i++)
1227 wait_on_page_writeback(pages[i]);
1228
1229 page_start = page_offset(pages[0]);
1230 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1231
1232 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1233 page_start, page_end - 1, 0, &cached_state);
1234 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1235 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1236 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1237 &cached_state, GFP_NOFS);
1238
1239 if (i_done != page_cnt) {
1240 spin_lock(&BTRFS_I(inode)->lock);
1241 BTRFS_I(inode)->outstanding_extents++;
1242 spin_unlock(&BTRFS_I(inode)->lock);
1243 btrfs_delalloc_release_space(inode,
1244 (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1245 }
1246
1247
1248 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1249 &cached_state, GFP_NOFS);
1250
1251 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1252 page_start, page_end - 1, &cached_state,
1253 GFP_NOFS);
1254
1255 for (i = 0; i < i_done; i++) {
1256 clear_page_dirty_for_io(pages[i]);
1257 ClearPageChecked(pages[i]);
1258 set_page_extent_mapped(pages[i]);
1259 set_page_dirty(pages[i]);
1260 unlock_page(pages[i]);
1261 page_cache_release(pages[i]);
1262 }
1263 return i_done;
1264 out:
1265 for (i = 0; i < i_done; i++) {
1266 unlock_page(pages[i]);
1267 page_cache_release(pages[i]);
1268 }
1269 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1270 return ret;
1271
1272 }
1273
1274 int btrfs_defrag_file(struct inode *inode, struct file *file,
1275 struct btrfs_ioctl_defrag_range_args *range,
1276 u64 newer_than, unsigned long max_to_defrag)
1277 {
1278 struct btrfs_root *root = BTRFS_I(inode)->root;
1279 struct file_ra_state *ra = NULL;
1280 unsigned long last_index;
1281 u64 isize = i_size_read(inode);
1282 u64 last_len = 0;
1283 u64 skip = 0;
1284 u64 defrag_end = 0;
1285 u64 newer_off = range->start;
1286 unsigned long i;
1287 unsigned long ra_index = 0;
1288 int ret;
1289 int defrag_count = 0;
1290 int compress_type = BTRFS_COMPRESS_ZLIB;
1291 int extent_thresh = range->extent_thresh;
1292 unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1293 unsigned long cluster = max_cluster;
1294 u64 new_align = ~((u64)128 * 1024 - 1);
1295 struct page **pages = NULL;
1296
1297 if (isize == 0)
1298 return 0;
1299
1300 if (range->start >= isize)
1301 return -EINVAL;
1302
1303 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1304 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1305 return -EINVAL;
1306 if (range->compress_type)
1307 compress_type = range->compress_type;
1308 }
1309
1310 if (extent_thresh == 0)
1311 extent_thresh = 256 * 1024;
1312
1313 /*
1314 * if we were not given a file, allocate a readahead
1315 * context
1316 */
1317 if (!file) {
1318 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1319 if (!ra)
1320 return -ENOMEM;
1321 file_ra_state_init(ra, inode->i_mapping);
1322 } else {
1323 ra = &file->f_ra;
1324 }
1325
1326 pages = kmalloc_array(max_cluster, sizeof(struct page *),
1327 GFP_NOFS);
1328 if (!pages) {
1329 ret = -ENOMEM;
1330 goto out_ra;
1331 }
1332
1333 /* find the last page to defrag */
1334 if (range->start + range->len > range->start) {
1335 last_index = min_t(u64, isize - 1,
1336 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1337 } else {
1338 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1339 }
1340
1341 if (newer_than) {
1342 ret = find_new_extents(root, inode, newer_than,
1343 &newer_off, 64 * 1024);
1344 if (!ret) {
1345 range->start = newer_off;
1346 /*
1347 * we always align our defrag to help keep
1348 * the extents in the file evenly spaced
1349 */
1350 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1351 } else
1352 goto out_ra;
1353 } else {
1354 i = range->start >> PAGE_CACHE_SHIFT;
1355 }
1356 if (!max_to_defrag)
1357 max_to_defrag = last_index + 1;
1358
1359 /*
1360 * make writeback starts from i, so the defrag range can be
1361 * written sequentially.
1362 */
1363 if (i < inode->i_mapping->writeback_index)
1364 inode->i_mapping->writeback_index = i;
1365
1366 while (i <= last_index && defrag_count < max_to_defrag &&
1367 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1368 PAGE_CACHE_SHIFT)) {
1369 /*
1370 * make sure we stop running if someone unmounts
1371 * the FS
1372 */
1373 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1374 break;
1375
1376 if (btrfs_defrag_cancelled(root->fs_info)) {
1377 printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n");
1378 ret = -EAGAIN;
1379 break;
1380 }
1381
1382 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1383 extent_thresh, &last_len, &skip,
1384 &defrag_end, range->flags &
1385 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1386 unsigned long next;
1387 /*
1388 * the should_defrag function tells us how much to skip
1389 * bump our counter by the suggested amount
1390 */
1391 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1392 i = max(i + 1, next);
1393 continue;
1394 }
1395
1396 if (!newer_than) {
1397 cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1398 PAGE_CACHE_SHIFT) - i;
1399 cluster = min(cluster, max_cluster);
1400 } else {
1401 cluster = max_cluster;
1402 }
1403
1404 if (i + cluster > ra_index) {
1405 ra_index = max(i, ra_index);
1406 btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1407 cluster);
1408 ra_index += max_cluster;
1409 }
1410
1411 mutex_lock(&inode->i_mutex);
1412 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1413 BTRFS_I(inode)->force_compress = compress_type;
1414 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1415 if (ret < 0) {
1416 mutex_unlock(&inode->i_mutex);
1417 goto out_ra;
1418 }
1419
1420 defrag_count += ret;
1421 balance_dirty_pages_ratelimited(inode->i_mapping);
1422 mutex_unlock(&inode->i_mutex);
1423
1424 if (newer_than) {
1425 if (newer_off == (u64)-1)
1426 break;
1427
1428 if (ret > 0)
1429 i += ret;
1430
1431 newer_off = max(newer_off + 1,
1432 (u64)i << PAGE_CACHE_SHIFT);
1433
1434 ret = find_new_extents(root, inode,
1435 newer_than, &newer_off,
1436 64 * 1024);
1437 if (!ret) {
1438 range->start = newer_off;
1439 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1440 } else {
1441 break;
1442 }
1443 } else {
1444 if (ret > 0) {
1445 i += ret;
1446 last_len += ret << PAGE_CACHE_SHIFT;
1447 } else {
1448 i++;
1449 last_len = 0;
1450 }
1451 }
1452 }
1453
1454 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1455 filemap_flush(inode->i_mapping);
1456 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1457 &BTRFS_I(inode)->runtime_flags))
1458 filemap_flush(inode->i_mapping);
1459 }
1460
1461 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1462 /* the filemap_flush will queue IO into the worker threads, but
1463 * we have to make sure the IO is actually started and that
1464 * ordered extents get created before we return
1465 */
1466 atomic_inc(&root->fs_info->async_submit_draining);
1467 while (atomic_read(&root->fs_info->nr_async_submits) ||
1468 atomic_read(&root->fs_info->async_delalloc_pages)) {
1469 wait_event(root->fs_info->async_submit_wait,
1470 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1471 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1472 }
1473 atomic_dec(&root->fs_info->async_submit_draining);
1474 }
1475
1476 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1477 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1478 }
1479
1480 ret = defrag_count;
1481
1482 out_ra:
1483 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1484 mutex_lock(&inode->i_mutex);
1485 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1486 mutex_unlock(&inode->i_mutex);
1487 }
1488 if (!file)
1489 kfree(ra);
1490 kfree(pages);
1491 return ret;
1492 }
1493
1494 static noinline int btrfs_ioctl_resize(struct file *file,
1495 void __user *arg)
1496 {
1497 u64 new_size;
1498 u64 old_size;
1499 u64 devid = 1;
1500 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
1501 struct btrfs_ioctl_vol_args *vol_args;
1502 struct btrfs_trans_handle *trans;
1503 struct btrfs_device *device = NULL;
1504 char *sizestr;
1505 char *retptr;
1506 char *devstr = NULL;
1507 int ret = 0;
1508 int mod = 0;
1509
1510 if (!capable(CAP_SYS_ADMIN))
1511 return -EPERM;
1512
1513 ret = mnt_want_write_file(file);
1514 if (ret)
1515 return ret;
1516
1517 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1518 1)) {
1519 mnt_drop_write_file(file);
1520 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1521 }
1522
1523 mutex_lock(&root->fs_info->volume_mutex);
1524 vol_args = memdup_user(arg, sizeof(*vol_args));
1525 if (IS_ERR(vol_args)) {
1526 ret = PTR_ERR(vol_args);
1527 goto out;
1528 }
1529
1530 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1531
1532 sizestr = vol_args->name;
1533 devstr = strchr(sizestr, ':');
1534 if (devstr) {
1535 sizestr = devstr + 1;
1536 *devstr = '\0';
1537 devstr = vol_args->name;
1538 ret = kstrtoull(devstr, 10, &devid);
1539 if (ret)
1540 goto out_free;
1541 if (!devid) {
1542 ret = -EINVAL;
1543 goto out_free;
1544 }
1545 btrfs_info(root->fs_info, "resizing devid %llu", devid);
1546 }
1547
1548 device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1549 if (!device) {
1550 btrfs_info(root->fs_info, "resizer unable to find device %llu",
1551 devid);
1552 ret = -ENODEV;
1553 goto out_free;
1554 }
1555
1556 if (!device->writeable) {
1557 btrfs_info(root->fs_info,
1558 "resizer unable to apply on readonly device %llu",
1559 devid);
1560 ret = -EPERM;
1561 goto out_free;
1562 }
1563
1564 if (!strcmp(sizestr, "max"))
1565 new_size = device->bdev->bd_inode->i_size;
1566 else {
1567 if (sizestr[0] == '-') {
1568 mod = -1;
1569 sizestr++;
1570 } else if (sizestr[0] == '+') {
1571 mod = 1;
1572 sizestr++;
1573 }
1574 new_size = memparse(sizestr, &retptr);
1575 if (*retptr != '\0' || new_size == 0) {
1576 ret = -EINVAL;
1577 goto out_free;
1578 }
1579 }
1580
1581 if (device->is_tgtdev_for_dev_replace) {
1582 ret = -EPERM;
1583 goto out_free;
1584 }
1585
1586 old_size = device->total_bytes;
1587
1588 if (mod < 0) {
1589 if (new_size > old_size) {
1590 ret = -EINVAL;
1591 goto out_free;
1592 }
1593 new_size = old_size - new_size;
1594 } else if (mod > 0) {
1595 if (new_size > ULLONG_MAX - old_size) {
1596 ret = -ERANGE;
1597 goto out_free;
1598 }
1599 new_size = old_size + new_size;
1600 }
1601
1602 if (new_size < 256 * 1024 * 1024) {
1603 ret = -EINVAL;
1604 goto out_free;
1605 }
1606 if (new_size > device->bdev->bd_inode->i_size) {
1607 ret = -EFBIG;
1608 goto out_free;
1609 }
1610
1611 do_div(new_size, root->sectorsize);
1612 new_size *= root->sectorsize;
1613
1614 printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n",
1615 rcu_str_deref(device->name), new_size);
1616
1617 if (new_size > old_size) {
1618 trans = btrfs_start_transaction(root, 0);
1619 if (IS_ERR(trans)) {
1620 ret = PTR_ERR(trans);
1621 goto out_free;
1622 }
1623 ret = btrfs_grow_device(trans, device, new_size);
1624 btrfs_commit_transaction(trans, root);
1625 } else if (new_size < old_size) {
1626 ret = btrfs_shrink_device(device, new_size);
1627 } /* equal, nothing need to do */
1628
1629 out_free:
1630 kfree(vol_args);
1631 out:
1632 mutex_unlock(&root->fs_info->volume_mutex);
1633 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1634 mnt_drop_write_file(file);
1635 return ret;
1636 }
1637
1638 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1639 char *name, unsigned long fd, int subvol,
1640 u64 *transid, bool readonly,
1641 struct btrfs_qgroup_inherit *inherit)
1642 {
1643 int namelen;
1644 int ret = 0;
1645
1646 ret = mnt_want_write_file(file);
1647 if (ret)
1648 goto out;
1649
1650 namelen = strlen(name);
1651 if (strchr(name, '/')) {
1652 ret = -EINVAL;
1653 goto out_drop_write;
1654 }
1655
1656 if (name[0] == '.' &&
1657 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1658 ret = -EEXIST;
1659 goto out_drop_write;
1660 }
1661
1662 if (subvol) {
1663 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1664 NULL, transid, readonly, inherit);
1665 } else {
1666 struct fd src = fdget(fd);
1667 struct inode *src_inode;
1668 if (!src.file) {
1669 ret = -EINVAL;
1670 goto out_drop_write;
1671 }
1672
1673 src_inode = file_inode(src.file);
1674 if (src_inode->i_sb != file_inode(file)->i_sb) {
1675 btrfs_info(BTRFS_I(src_inode)->root->fs_info,
1676 "Snapshot src from another FS");
1677 ret = -EXDEV;
1678 } else if (!inode_owner_or_capable(src_inode)) {
1679 /*
1680 * Subvolume creation is not restricted, but snapshots
1681 * are limited to own subvolumes only
1682 */
1683 ret = -EPERM;
1684 } else {
1685 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1686 BTRFS_I(src_inode)->root,
1687 transid, readonly, inherit);
1688 }
1689 fdput(src);
1690 }
1691 out_drop_write:
1692 mnt_drop_write_file(file);
1693 out:
1694 return ret;
1695 }
1696
1697 static noinline int btrfs_ioctl_snap_create(struct file *file,
1698 void __user *arg, int subvol)
1699 {
1700 struct btrfs_ioctl_vol_args *vol_args;
1701 int ret;
1702
1703 vol_args = memdup_user(arg, sizeof(*vol_args));
1704 if (IS_ERR(vol_args))
1705 return PTR_ERR(vol_args);
1706 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1707
1708 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1709 vol_args->fd, subvol,
1710 NULL, false, NULL);
1711
1712 kfree(vol_args);
1713 return ret;
1714 }
1715
1716 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1717 void __user *arg, int subvol)
1718 {
1719 struct btrfs_ioctl_vol_args_v2 *vol_args;
1720 int ret;
1721 u64 transid = 0;
1722 u64 *ptr = NULL;
1723 bool readonly = false;
1724 struct btrfs_qgroup_inherit *inherit = NULL;
1725
1726 vol_args = memdup_user(arg, sizeof(*vol_args));
1727 if (IS_ERR(vol_args))
1728 return PTR_ERR(vol_args);
1729 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1730
1731 if (vol_args->flags &
1732 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1733 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1734 ret = -EOPNOTSUPP;
1735 goto out;
1736 }
1737
1738 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1739 ptr = &transid;
1740 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1741 readonly = true;
1742 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1743 if (vol_args->size > PAGE_CACHE_SIZE) {
1744 ret = -EINVAL;
1745 goto out;
1746 }
1747 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1748 if (IS_ERR(inherit)) {
1749 ret = PTR_ERR(inherit);
1750 goto out;
1751 }
1752 }
1753
1754 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1755 vol_args->fd, subvol, ptr,
1756 readonly, inherit);
1757
1758 if (ret == 0 && ptr &&
1759 copy_to_user(arg +
1760 offsetof(struct btrfs_ioctl_vol_args_v2,
1761 transid), ptr, sizeof(*ptr)))
1762 ret = -EFAULT;
1763 out:
1764 kfree(vol_args);
1765 kfree(inherit);
1766 return ret;
1767 }
1768
1769 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1770 void __user *arg)
1771 {
1772 struct inode *inode = file_inode(file);
1773 struct btrfs_root *root = BTRFS_I(inode)->root;
1774 int ret = 0;
1775 u64 flags = 0;
1776
1777 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1778 return -EINVAL;
1779
1780 down_read(&root->fs_info->subvol_sem);
1781 if (btrfs_root_readonly(root))
1782 flags |= BTRFS_SUBVOL_RDONLY;
1783 up_read(&root->fs_info->subvol_sem);
1784
1785 if (copy_to_user(arg, &flags, sizeof(flags)))
1786 ret = -EFAULT;
1787
1788 return ret;
1789 }
1790
1791 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1792 void __user *arg)
1793 {
1794 struct inode *inode = file_inode(file);
1795 struct btrfs_root *root = BTRFS_I(inode)->root;
1796 struct btrfs_trans_handle *trans;
1797 u64 root_flags;
1798 u64 flags;
1799 int ret = 0;
1800
1801 if (!inode_owner_or_capable(inode))
1802 return -EPERM;
1803
1804 ret = mnt_want_write_file(file);
1805 if (ret)
1806 goto out;
1807
1808 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1809 ret = -EINVAL;
1810 goto out_drop_write;
1811 }
1812
1813 if (copy_from_user(&flags, arg, sizeof(flags))) {
1814 ret = -EFAULT;
1815 goto out_drop_write;
1816 }
1817
1818 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1819 ret = -EINVAL;
1820 goto out_drop_write;
1821 }
1822
1823 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1824 ret = -EOPNOTSUPP;
1825 goto out_drop_write;
1826 }
1827
1828 down_write(&root->fs_info->subvol_sem);
1829
1830 /* nothing to do */
1831 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1832 goto out_drop_sem;
1833
1834 root_flags = btrfs_root_flags(&root->root_item);
1835 if (flags & BTRFS_SUBVOL_RDONLY) {
1836 btrfs_set_root_flags(&root->root_item,
1837 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1838 } else {
1839 /*
1840 * Block RO -> RW transition if this subvolume is involved in
1841 * send
1842 */
1843 spin_lock(&root->root_item_lock);
1844 if (root->send_in_progress == 0) {
1845 btrfs_set_root_flags(&root->root_item,
1846 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1847 spin_unlock(&root->root_item_lock);
1848 } else {
1849 spin_unlock(&root->root_item_lock);
1850 btrfs_warn(root->fs_info,
1851 "Attempt to set subvolume %llu read-write during send",
1852 root->root_key.objectid);
1853 ret = -EPERM;
1854 goto out_drop_sem;
1855 }
1856 }
1857
1858 trans = btrfs_start_transaction(root, 1);
1859 if (IS_ERR(trans)) {
1860 ret = PTR_ERR(trans);
1861 goto out_reset;
1862 }
1863
1864 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1865 &root->root_key, &root->root_item);
1866
1867 btrfs_commit_transaction(trans, root);
1868 out_reset:
1869 if (ret)
1870 btrfs_set_root_flags(&root->root_item, root_flags);
1871 out_drop_sem:
1872 up_write(&root->fs_info->subvol_sem);
1873 out_drop_write:
1874 mnt_drop_write_file(file);
1875 out:
1876 return ret;
1877 }
1878
1879 /*
1880 * helper to check if the subvolume references other subvolumes
1881 */
1882 static noinline int may_destroy_subvol(struct btrfs_root *root)
1883 {
1884 struct btrfs_path *path;
1885 struct btrfs_dir_item *di;
1886 struct btrfs_key key;
1887 u64 dir_id;
1888 int ret;
1889
1890 path = btrfs_alloc_path();
1891 if (!path)
1892 return -ENOMEM;
1893
1894 /* Make sure this root isn't set as the default subvol */
1895 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
1896 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
1897 dir_id, "default", 7, 0);
1898 if (di && !IS_ERR(di)) {
1899 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1900 if (key.objectid == root->root_key.objectid) {
1901 ret = -EPERM;
1902 btrfs_err(root->fs_info, "deleting default subvolume "
1903 "%llu is not allowed", key.objectid);
1904 goto out;
1905 }
1906 btrfs_release_path(path);
1907 }
1908
1909 key.objectid = root->root_key.objectid;
1910 key.type = BTRFS_ROOT_REF_KEY;
1911 key.offset = (u64)-1;
1912
1913 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1914 &key, path, 0, 0);
1915 if (ret < 0)
1916 goto out;
1917 BUG_ON(ret == 0);
1918
1919 ret = 0;
1920 if (path->slots[0] > 0) {
1921 path->slots[0]--;
1922 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1923 if (key.objectid == root->root_key.objectid &&
1924 key.type == BTRFS_ROOT_REF_KEY)
1925 ret = -ENOTEMPTY;
1926 }
1927 out:
1928 btrfs_free_path(path);
1929 return ret;
1930 }
1931
1932 static noinline int key_in_sk(struct btrfs_key *key,
1933 struct btrfs_ioctl_search_key *sk)
1934 {
1935 struct btrfs_key test;
1936 int ret;
1937
1938 test.objectid = sk->min_objectid;
1939 test.type = sk->min_type;
1940 test.offset = sk->min_offset;
1941
1942 ret = btrfs_comp_cpu_keys(key, &test);
1943 if (ret < 0)
1944 return 0;
1945
1946 test.objectid = sk->max_objectid;
1947 test.type = sk->max_type;
1948 test.offset = sk->max_offset;
1949
1950 ret = btrfs_comp_cpu_keys(key, &test);
1951 if (ret > 0)
1952 return 0;
1953 return 1;
1954 }
1955
1956 static noinline int copy_to_sk(struct btrfs_root *root,
1957 struct btrfs_path *path,
1958 struct btrfs_key *key,
1959 struct btrfs_ioctl_search_key *sk,
1960 size_t *buf_size,
1961 char __user *ubuf,
1962 unsigned long *sk_offset,
1963 int *num_found)
1964 {
1965 u64 found_transid;
1966 struct extent_buffer *leaf;
1967 struct btrfs_ioctl_search_header sh;
1968 unsigned long item_off;
1969 unsigned long item_len;
1970 int nritems;
1971 int i;
1972 int slot;
1973 int ret = 0;
1974
1975 leaf = path->nodes[0];
1976 slot = path->slots[0];
1977 nritems = btrfs_header_nritems(leaf);
1978
1979 if (btrfs_header_generation(leaf) > sk->max_transid) {
1980 i = nritems;
1981 goto advance_key;
1982 }
1983 found_transid = btrfs_header_generation(leaf);
1984
1985 for (i = slot; i < nritems; i++) {
1986 item_off = btrfs_item_ptr_offset(leaf, i);
1987 item_len = btrfs_item_size_nr(leaf, i);
1988
1989 btrfs_item_key_to_cpu(leaf, key, i);
1990 if (!key_in_sk(key, sk))
1991 continue;
1992
1993 if (sizeof(sh) + item_len > *buf_size) {
1994 if (*num_found) {
1995 ret = 1;
1996 goto out;
1997 }
1998
1999 /*
2000 * return one empty item back for v1, which does not
2001 * handle -EOVERFLOW
2002 */
2003
2004 *buf_size = sizeof(sh) + item_len;
2005 item_len = 0;
2006 ret = -EOVERFLOW;
2007 }
2008
2009 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2010 ret = 1;
2011 goto out;
2012 }
2013
2014 sh.objectid = key->objectid;
2015 sh.offset = key->offset;
2016 sh.type = key->type;
2017 sh.len = item_len;
2018 sh.transid = found_transid;
2019
2020 /* copy search result header */
2021 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
2022 ret = -EFAULT;
2023 goto out;
2024 }
2025
2026 *sk_offset += sizeof(sh);
2027
2028 if (item_len) {
2029 char __user *up = ubuf + *sk_offset;
2030 /* copy the item */
2031 if (read_extent_buffer_to_user(leaf, up,
2032 item_off, item_len)) {
2033 ret = -EFAULT;
2034 goto out;
2035 }
2036
2037 *sk_offset += item_len;
2038 }
2039 (*num_found)++;
2040
2041 if (ret) /* -EOVERFLOW from above */
2042 goto out;
2043
2044 if (*num_found >= sk->nr_items) {
2045 ret = 1;
2046 goto out;
2047 }
2048 }
2049 advance_key:
2050 ret = 0;
2051 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
2052 key->offset++;
2053 else if (key->type < (u8)-1 && key->type < sk->max_type) {
2054 key->offset = 0;
2055 key->type++;
2056 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
2057 key->offset = 0;
2058 key->type = 0;
2059 key->objectid++;
2060 } else
2061 ret = 1;
2062 out:
2063 /*
2064 * 0: all items from this leaf copied, continue with next
2065 * 1: * more items can be copied, but unused buffer is too small
2066 * * all items were found
2067 * Either way, it will stops the loop which iterates to the next
2068 * leaf
2069 * -EOVERFLOW: item was to large for buffer
2070 * -EFAULT: could not copy extent buffer back to userspace
2071 */
2072 return ret;
2073 }
2074
2075 static noinline int search_ioctl(struct inode *inode,
2076 struct btrfs_ioctl_search_key *sk,
2077 size_t *buf_size,
2078 char __user *ubuf)
2079 {
2080 struct btrfs_root *root;
2081 struct btrfs_key key;
2082 struct btrfs_path *path;
2083 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
2084 int ret;
2085 int num_found = 0;
2086 unsigned long sk_offset = 0;
2087
2088 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2089 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2090 return -EOVERFLOW;
2091 }
2092
2093 path = btrfs_alloc_path();
2094 if (!path)
2095 return -ENOMEM;
2096
2097 if (sk->tree_id == 0) {
2098 /* search the root of the inode that was passed */
2099 root = BTRFS_I(inode)->root;
2100 } else {
2101 key.objectid = sk->tree_id;
2102 key.type = BTRFS_ROOT_ITEM_KEY;
2103 key.offset = (u64)-1;
2104 root = btrfs_read_fs_root_no_name(info, &key);
2105 if (IS_ERR(root)) {
2106 printk(KERN_ERR "BTRFS: could not find root %llu\n",
2107 sk->tree_id);
2108 btrfs_free_path(path);
2109 return -ENOENT;
2110 }
2111 }
2112
2113 key.objectid = sk->min_objectid;
2114 key.type = sk->min_type;
2115 key.offset = sk->min_offset;
2116
2117 path->keep_locks = 1;
2118
2119 while (1) {
2120 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2121 if (ret != 0) {
2122 if (ret > 0)
2123 ret = 0;
2124 goto err;
2125 }
2126 ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf,
2127 &sk_offset, &num_found);
2128 btrfs_release_path(path);
2129 if (ret)
2130 break;
2131
2132 }
2133 if (ret > 0)
2134 ret = 0;
2135 err:
2136 sk->nr_items = num_found;
2137 btrfs_free_path(path);
2138 return ret;
2139 }
2140
2141 static noinline int btrfs_ioctl_tree_search(struct file *file,
2142 void __user *argp)
2143 {
2144 struct btrfs_ioctl_search_args __user *uargs;
2145 struct btrfs_ioctl_search_key sk;
2146 struct inode *inode;
2147 int ret;
2148 size_t buf_size;
2149
2150 if (!capable(CAP_SYS_ADMIN))
2151 return -EPERM;
2152
2153 uargs = (struct btrfs_ioctl_search_args __user *)argp;
2154
2155 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2156 return -EFAULT;
2157
2158 buf_size = sizeof(uargs->buf);
2159
2160 inode = file_inode(file);
2161 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2162
2163 /*
2164 * In the origin implementation an overflow is handled by returning a
2165 * search header with a len of zero, so reset ret.
2166 */
2167 if (ret == -EOVERFLOW)
2168 ret = 0;
2169
2170 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2171 ret = -EFAULT;
2172 return ret;
2173 }
2174
2175 static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2176 void __user *argp)
2177 {
2178 struct btrfs_ioctl_search_args_v2 __user *uarg;
2179 struct btrfs_ioctl_search_args_v2 args;
2180 struct inode *inode;
2181 int ret;
2182 size_t buf_size;
2183 const size_t buf_limit = 16 * 1024 * 1024;
2184
2185 if (!capable(CAP_SYS_ADMIN))
2186 return -EPERM;
2187
2188 /* copy search header and buffer size */
2189 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2190 if (copy_from_user(&args, uarg, sizeof(args)))
2191 return -EFAULT;
2192
2193 buf_size = args.buf_size;
2194
2195 if (buf_size < sizeof(struct btrfs_ioctl_search_header))
2196 return -EOVERFLOW;
2197
2198 /* limit result size to 16MB */
2199 if (buf_size > buf_limit)
2200 buf_size = buf_limit;
2201
2202 inode = file_inode(file);
2203 ret = search_ioctl(inode, &args.key, &buf_size,
2204 (char *)(&uarg->buf[0]));
2205 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2206 ret = -EFAULT;
2207 else if (ret == -EOVERFLOW &&
2208 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2209 ret = -EFAULT;
2210
2211 return ret;
2212 }
2213
2214 /*
2215 * Search INODE_REFs to identify path name of 'dirid' directory
2216 * in a 'tree_id' tree. and sets path name to 'name'.
2217 */
2218 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2219 u64 tree_id, u64 dirid, char *name)
2220 {
2221 struct btrfs_root *root;
2222 struct btrfs_key key;
2223 char *ptr;
2224 int ret = -1;
2225 int slot;
2226 int len;
2227 int total_len = 0;
2228 struct btrfs_inode_ref *iref;
2229 struct extent_buffer *l;
2230 struct btrfs_path *path;
2231
2232 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2233 name[0]='\0';
2234 return 0;
2235 }
2236
2237 path = btrfs_alloc_path();
2238 if (!path)
2239 return -ENOMEM;
2240
2241 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2242
2243 key.objectid = tree_id;
2244 key.type = BTRFS_ROOT_ITEM_KEY;
2245 key.offset = (u64)-1;
2246 root = btrfs_read_fs_root_no_name(info, &key);
2247 if (IS_ERR(root)) {
2248 printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id);
2249 ret = -ENOENT;
2250 goto out;
2251 }
2252
2253 key.objectid = dirid;
2254 key.type = BTRFS_INODE_REF_KEY;
2255 key.offset = (u64)-1;
2256
2257 while (1) {
2258 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2259 if (ret < 0)
2260 goto out;
2261 else if (ret > 0) {
2262 ret = btrfs_previous_item(root, path, dirid,
2263 BTRFS_INODE_REF_KEY);
2264 if (ret < 0)
2265 goto out;
2266 else if (ret > 0) {
2267 ret = -ENOENT;
2268 goto out;
2269 }
2270 }
2271
2272 l = path->nodes[0];
2273 slot = path->slots[0];
2274 btrfs_item_key_to_cpu(l, &key, slot);
2275
2276 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2277 len = btrfs_inode_ref_name_len(l, iref);
2278 ptr -= len + 1;
2279 total_len += len + 1;
2280 if (ptr < name) {
2281 ret = -ENAMETOOLONG;
2282 goto out;
2283 }
2284
2285 *(ptr + len) = '/';
2286 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2287
2288 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2289 break;
2290
2291 btrfs_release_path(path);
2292 key.objectid = key.offset;
2293 key.offset = (u64)-1;
2294 dirid = key.objectid;
2295 }
2296 memmove(name, ptr, total_len);
2297 name[total_len] = '\0';
2298 ret = 0;
2299 out:
2300 btrfs_free_path(path);
2301 return ret;
2302 }
2303
2304 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2305 void __user *argp)
2306 {
2307 struct btrfs_ioctl_ino_lookup_args *args;
2308 struct inode *inode;
2309 int ret;
2310
2311 if (!capable(CAP_SYS_ADMIN))
2312 return -EPERM;
2313
2314 args = memdup_user(argp, sizeof(*args));
2315 if (IS_ERR(args))
2316 return PTR_ERR(args);
2317
2318 inode = file_inode(file);
2319
2320 if (args->treeid == 0)
2321 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2322
2323 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2324 args->treeid, args->objectid,
2325 args->name);
2326
2327 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2328 ret = -EFAULT;
2329
2330 kfree(args);
2331 return ret;
2332 }
2333
2334 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2335 void __user *arg)
2336 {
2337 struct dentry *parent = file->f_path.dentry;
2338 struct dentry *dentry;
2339 struct inode *dir = parent->d_inode;
2340 struct inode *inode;
2341 struct btrfs_root *root = BTRFS_I(dir)->root;
2342 struct btrfs_root *dest = NULL;
2343 struct btrfs_ioctl_vol_args *vol_args;
2344 struct btrfs_trans_handle *trans;
2345 struct btrfs_block_rsv block_rsv;
2346 u64 root_flags;
2347 u64 qgroup_reserved;
2348 int namelen;
2349 int ret;
2350 int err = 0;
2351
2352 vol_args = memdup_user(arg, sizeof(*vol_args));
2353 if (IS_ERR(vol_args))
2354 return PTR_ERR(vol_args);
2355
2356 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2357 namelen = strlen(vol_args->name);
2358 if (strchr(vol_args->name, '/') ||
2359 strncmp(vol_args->name, "..", namelen) == 0) {
2360 err = -EINVAL;
2361 goto out;
2362 }
2363
2364 err = mnt_want_write_file(file);
2365 if (err)
2366 goto out;
2367
2368
2369 err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
2370 if (err == -EINTR)
2371 goto out_drop_write;
2372 dentry = lookup_one_len(vol_args->name, parent, namelen);
2373 if (IS_ERR(dentry)) {
2374 err = PTR_ERR(dentry);
2375 goto out_unlock_dir;
2376 }
2377
2378 if (!dentry->d_inode) {
2379 err = -ENOENT;
2380 goto out_dput;
2381 }
2382
2383 inode = dentry->d_inode;
2384 dest = BTRFS_I(inode)->root;
2385 if (!capable(CAP_SYS_ADMIN)) {
2386 /*
2387 * Regular user. Only allow this with a special mount
2388 * option, when the user has write+exec access to the
2389 * subvol root, and when rmdir(2) would have been
2390 * allowed.
2391 *
2392 * Note that this is _not_ check that the subvol is
2393 * empty or doesn't contain data that we wouldn't
2394 * otherwise be able to delete.
2395 *
2396 * Users who want to delete empty subvols should try
2397 * rmdir(2).
2398 */
2399 err = -EPERM;
2400 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2401 goto out_dput;
2402
2403 /*
2404 * Do not allow deletion if the parent dir is the same
2405 * as the dir to be deleted. That means the ioctl
2406 * must be called on the dentry referencing the root
2407 * of the subvol, not a random directory contained
2408 * within it.
2409 */
2410 err = -EINVAL;
2411 if (root == dest)
2412 goto out_dput;
2413
2414 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2415 if (err)
2416 goto out_dput;
2417 }
2418
2419 /* check if subvolume may be deleted by a user */
2420 err = btrfs_may_delete(dir, dentry, 1);
2421 if (err)
2422 goto out_dput;
2423
2424 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2425 err = -EINVAL;
2426 goto out_dput;
2427 }
2428
2429 mutex_lock(&inode->i_mutex);
2430
2431 /*
2432 * Don't allow to delete a subvolume with send in progress. This is
2433 * inside the i_mutex so the error handling that has to drop the bit
2434 * again is not run concurrently.
2435 */
2436 spin_lock(&dest->root_item_lock);
2437 root_flags = btrfs_root_flags(&dest->root_item);
2438 if (dest->send_in_progress == 0) {
2439 btrfs_set_root_flags(&dest->root_item,
2440 root_flags | BTRFS_ROOT_SUBVOL_DEAD);
2441 spin_unlock(&dest->root_item_lock);
2442 } else {
2443 spin_unlock(&dest->root_item_lock);
2444 btrfs_warn(root->fs_info,
2445 "Attempt to delete subvolume %llu during send",
2446 dest->root_key.objectid);
2447 err = -EPERM;
2448 goto out_dput;
2449 }
2450
2451 err = d_invalidate(dentry);
2452 if (err)
2453 goto out_unlock;
2454
2455 down_write(&root->fs_info->subvol_sem);
2456
2457 err = may_destroy_subvol(dest);
2458 if (err)
2459 goto out_up_write;
2460
2461 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2462 /*
2463 * One for dir inode, two for dir entries, two for root
2464 * ref/backref.
2465 */
2466 err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2467 5, &qgroup_reserved, true);
2468 if (err)
2469 goto out_up_write;
2470
2471 trans = btrfs_start_transaction(root, 0);
2472 if (IS_ERR(trans)) {
2473 err = PTR_ERR(trans);
2474 goto out_release;
2475 }
2476 trans->block_rsv = &block_rsv;
2477 trans->bytes_reserved = block_rsv.size;
2478
2479 ret = btrfs_unlink_subvol(trans, root, dir,
2480 dest->root_key.objectid,
2481 dentry->d_name.name,
2482 dentry->d_name.len);
2483 if (ret) {
2484 err = ret;
2485 btrfs_abort_transaction(trans, root, ret);
2486 goto out_end_trans;
2487 }
2488
2489 btrfs_record_root_in_trans(trans, dest);
2490
2491 memset(&dest->root_item.drop_progress, 0,
2492 sizeof(dest->root_item.drop_progress));
2493 dest->root_item.drop_level = 0;
2494 btrfs_set_root_refs(&dest->root_item, 0);
2495
2496 if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
2497 ret = btrfs_insert_orphan_item(trans,
2498 root->fs_info->tree_root,
2499 dest->root_key.objectid);
2500 if (ret) {
2501 btrfs_abort_transaction(trans, root, ret);
2502 err = ret;
2503 goto out_end_trans;
2504 }
2505 }
2506
2507 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2508 dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
2509 dest->root_key.objectid);
2510 if (ret && ret != -ENOENT) {
2511 btrfs_abort_transaction(trans, root, ret);
2512 err = ret;
2513 goto out_end_trans;
2514 }
2515 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
2516 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2517 dest->root_item.received_uuid,
2518 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
2519 dest->root_key.objectid);
2520 if (ret && ret != -ENOENT) {
2521 btrfs_abort_transaction(trans, root, ret);
2522 err = ret;
2523 goto out_end_trans;
2524 }
2525 }
2526
2527 out_end_trans:
2528 trans->block_rsv = NULL;
2529 trans->bytes_reserved = 0;
2530 ret = btrfs_end_transaction(trans, root);
2531 if (ret && !err)
2532 err = ret;
2533 inode->i_flags |= S_DEAD;
2534 out_release:
2535 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2536 out_up_write:
2537 up_write(&root->fs_info->subvol_sem);
2538 out_unlock:
2539 if (err) {
2540 spin_lock(&dest->root_item_lock);
2541 root_flags = btrfs_root_flags(&dest->root_item);
2542 btrfs_set_root_flags(&dest->root_item,
2543 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
2544 spin_unlock(&dest->root_item_lock);
2545 }
2546 mutex_unlock(&inode->i_mutex);
2547 if (!err) {
2548 shrink_dcache_sb(root->fs_info->sb);
2549 btrfs_invalidate_inodes(dest);
2550 d_delete(dentry);
2551 ASSERT(dest->send_in_progress == 0);
2552
2553 /* the last ref */
2554 if (dest->cache_inode) {
2555 iput(dest->cache_inode);
2556 dest->cache_inode = NULL;
2557 }
2558 }
2559 out_dput:
2560 dput(dentry);
2561 out_unlock_dir:
2562 mutex_unlock(&dir->i_mutex);
2563 out_drop_write:
2564 mnt_drop_write_file(file);
2565 out:
2566 kfree(vol_args);
2567 return err;
2568 }
2569
2570 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2571 {
2572 struct inode *inode = file_inode(file);
2573 struct btrfs_root *root = BTRFS_I(inode)->root;
2574 struct btrfs_ioctl_defrag_range_args *range;
2575 int ret;
2576
2577 ret = mnt_want_write_file(file);
2578 if (ret)
2579 return ret;
2580
2581 if (btrfs_root_readonly(root)) {
2582 ret = -EROFS;
2583 goto out;
2584 }
2585
2586 switch (inode->i_mode & S_IFMT) {
2587 case S_IFDIR:
2588 if (!capable(CAP_SYS_ADMIN)) {
2589 ret = -EPERM;
2590 goto out;
2591 }
2592 ret = btrfs_defrag_root(root);
2593 if (ret)
2594 goto out;
2595 ret = btrfs_defrag_root(root->fs_info->extent_root);
2596 break;
2597 case S_IFREG:
2598 if (!(file->f_mode & FMODE_WRITE)) {
2599 ret = -EINVAL;
2600 goto out;
2601 }
2602
2603 range = kzalloc(sizeof(*range), GFP_KERNEL);
2604 if (!range) {
2605 ret = -ENOMEM;
2606 goto out;
2607 }
2608
2609 if (argp) {
2610 if (copy_from_user(range, argp,
2611 sizeof(*range))) {
2612 ret = -EFAULT;
2613 kfree(range);
2614 goto out;
2615 }
2616 /* compression requires us to start the IO */
2617 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2618 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2619 range->extent_thresh = (u32)-1;
2620 }
2621 } else {
2622 /* the rest are all set to zero by kzalloc */
2623 range->len = (u64)-1;
2624 }
2625 ret = btrfs_defrag_file(file_inode(file), file,
2626 range, 0, 0);
2627 if (ret > 0)
2628 ret = 0;
2629 kfree(range);
2630 break;
2631 default:
2632 ret = -EINVAL;
2633 }
2634 out:
2635 mnt_drop_write_file(file);
2636 return ret;
2637 }
2638
2639 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2640 {
2641 struct btrfs_ioctl_vol_args *vol_args;
2642 int ret;
2643
2644 if (!capable(CAP_SYS_ADMIN))
2645 return -EPERM;
2646
2647 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2648 1)) {
2649 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2650 }
2651
2652 mutex_lock(&root->fs_info->volume_mutex);
2653 vol_args = memdup_user(arg, sizeof(*vol_args));
2654 if (IS_ERR(vol_args)) {
2655 ret = PTR_ERR(vol_args);
2656 goto out;
2657 }
2658
2659 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2660 ret = btrfs_init_new_device(root, vol_args->name);
2661
2662 kfree(vol_args);
2663 out:
2664 mutex_unlock(&root->fs_info->volume_mutex);
2665 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2666 return ret;
2667 }
2668
2669 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2670 {
2671 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
2672 struct btrfs_ioctl_vol_args *vol_args;
2673 int ret;
2674
2675 if (!capable(CAP_SYS_ADMIN))
2676 return -EPERM;
2677
2678 ret = mnt_want_write_file(file);
2679 if (ret)
2680 return ret;
2681
2682 vol_args = memdup_user(arg, sizeof(*vol_args));
2683 if (IS_ERR(vol_args)) {
2684 ret = PTR_ERR(vol_args);
2685 goto out;
2686 }
2687
2688 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2689
2690 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2691 1)) {
2692 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2693 goto out;
2694 }
2695
2696 mutex_lock(&root->fs_info->volume_mutex);
2697 ret = btrfs_rm_device(root, vol_args->name);
2698 mutex_unlock(&root->fs_info->volume_mutex);
2699 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2700
2701 out:
2702 kfree(vol_args);
2703 mnt_drop_write_file(file);
2704 return ret;
2705 }
2706
2707 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2708 {
2709 struct btrfs_ioctl_fs_info_args *fi_args;
2710 struct btrfs_device *device;
2711 struct btrfs_device *next;
2712 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2713 int ret = 0;
2714
2715 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2716 if (!fi_args)
2717 return -ENOMEM;
2718
2719 mutex_lock(&fs_devices->device_list_mutex);
2720 fi_args->num_devices = fs_devices->num_devices;
2721 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2722
2723 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2724 if (device->devid > fi_args->max_id)
2725 fi_args->max_id = device->devid;
2726 }
2727 mutex_unlock(&fs_devices->device_list_mutex);
2728
2729 fi_args->nodesize = root->fs_info->super_copy->nodesize;
2730 fi_args->sectorsize = root->fs_info->super_copy->sectorsize;
2731 fi_args->clone_alignment = root->fs_info->super_copy->sectorsize;
2732
2733 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2734 ret = -EFAULT;
2735
2736 kfree(fi_args);
2737 return ret;
2738 }
2739
2740 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2741 {
2742 struct btrfs_ioctl_dev_info_args *di_args;
2743 struct btrfs_device *dev;
2744 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2745 int ret = 0;
2746 char *s_uuid = NULL;
2747
2748 di_args = memdup_user(arg, sizeof(*di_args));
2749 if (IS_ERR(di_args))
2750 return PTR_ERR(di_args);
2751
2752 if (!btrfs_is_empty_uuid(di_args->uuid))
2753 s_uuid = di_args->uuid;
2754
2755 mutex_lock(&fs_devices->device_list_mutex);
2756 dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2757
2758 if (!dev) {
2759 ret = -ENODEV;
2760 goto out;
2761 }
2762
2763 di_args->devid = dev->devid;
2764 di_args->bytes_used = dev->bytes_used;
2765 di_args->total_bytes = dev->total_bytes;
2766 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2767 if (dev->name) {
2768 struct rcu_string *name;
2769
2770 rcu_read_lock();
2771 name = rcu_dereference(dev->name);
2772 strncpy(di_args->path, name->str, sizeof(di_args->path));
2773 rcu_read_unlock();
2774 di_args->path[sizeof(di_args->path) - 1] = 0;
2775 } else {
2776 di_args->path[0] = '\0';
2777 }
2778
2779 out:
2780 mutex_unlock(&fs_devices->device_list_mutex);
2781 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2782 ret = -EFAULT;
2783
2784 kfree(di_args);
2785 return ret;
2786 }
2787
2788 static struct page *extent_same_get_page(struct inode *inode, u64 off)
2789 {
2790 struct page *page;
2791 pgoff_t index;
2792 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
2793
2794 index = off >> PAGE_CACHE_SHIFT;
2795
2796 page = grab_cache_page(inode->i_mapping, index);
2797 if (!page)
2798 return NULL;
2799
2800 if (!PageUptodate(page)) {
2801 if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
2802 0))
2803 return NULL;
2804 lock_page(page);
2805 if (!PageUptodate(page)) {
2806 unlock_page(page);
2807 page_cache_release(page);
2808 return NULL;
2809 }
2810 }
2811 unlock_page(page);
2812
2813 return page;
2814 }
2815
2816 static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
2817 {
2818 /* do any pending delalloc/csum calc on src, one way or
2819 another, and lock file content */
2820 while (1) {
2821 struct btrfs_ordered_extent *ordered;
2822 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2823 ordered = btrfs_lookup_first_ordered_extent(inode,
2824 off + len - 1);
2825 if ((!ordered ||
2826 ordered->file_offset + ordered->len <= off ||
2827 ordered->file_offset >= off + len) &&
2828 !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2829 off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
2830 if (ordered)
2831 btrfs_put_ordered_extent(ordered);
2832 break;
2833 }
2834 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2835 if (ordered)
2836 btrfs_put_ordered_extent(ordered);
2837 btrfs_wait_ordered_range(inode, off, len);
2838 }
2839 }
2840
2841 static void btrfs_double_unlock(struct inode *inode1, u64 loff1,
2842 struct inode *inode2, u64 loff2, u64 len)
2843 {
2844 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
2845 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
2846
2847 mutex_unlock(&inode1->i_mutex);
2848 mutex_unlock(&inode2->i_mutex);
2849 }
2850
2851 static void btrfs_double_lock(struct inode *inode1, u64 loff1,
2852 struct inode *inode2, u64 loff2, u64 len)
2853 {
2854 if (inode1 < inode2) {
2855 swap(inode1, inode2);
2856 swap(loff1, loff2);
2857 }
2858
2859 mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
2860 lock_extent_range(inode1, loff1, len);
2861 if (inode1 != inode2) {
2862 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
2863 lock_extent_range(inode2, loff2, len);
2864 }
2865 }
2866
2867 static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
2868 u64 dst_loff, u64 len)
2869 {
2870 int ret = 0;
2871 struct page *src_page, *dst_page;
2872 unsigned int cmp_len = PAGE_CACHE_SIZE;
2873 void *addr, *dst_addr;
2874
2875 while (len) {
2876 if (len < PAGE_CACHE_SIZE)
2877 cmp_len = len;
2878
2879 src_page = extent_same_get_page(src, loff);
2880 if (!src_page)
2881 return -EINVAL;
2882 dst_page = extent_same_get_page(dst, dst_loff);
2883 if (!dst_page) {
2884 page_cache_release(src_page);
2885 return -EINVAL;
2886 }
2887 addr = kmap_atomic(src_page);
2888 dst_addr = kmap_atomic(dst_page);
2889
2890 flush_dcache_page(src_page);
2891 flush_dcache_page(dst_page);
2892
2893 if (memcmp(addr, dst_addr, cmp_len))
2894 ret = BTRFS_SAME_DATA_DIFFERS;
2895
2896 kunmap_atomic(addr);
2897 kunmap_atomic(dst_addr);
2898 page_cache_release(src_page);
2899 page_cache_release(dst_page);
2900
2901 if (ret)
2902 break;
2903
2904 loff += cmp_len;
2905 dst_loff += cmp_len;
2906 len -= cmp_len;
2907 }
2908
2909 return ret;
2910 }
2911
2912 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len)
2913 {
2914 u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
2915
2916 if (off + len > inode->i_size || off + len < off)
2917 return -EINVAL;
2918 /* Check that we are block aligned - btrfs_clone() requires this */
2919 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
2920 return -EINVAL;
2921
2922 return 0;
2923 }
2924
2925 static int btrfs_extent_same(struct inode *src, u64 loff, u64 len,
2926 struct inode *dst, u64 dst_loff)
2927 {
2928 int ret;
2929
2930 /*
2931 * btrfs_clone() can't handle extents in the same file
2932 * yet. Once that works, we can drop this check and replace it
2933 * with a check for the same inode, but overlapping extents.
2934 */
2935 if (src == dst)
2936 return -EINVAL;
2937
2938 btrfs_double_lock(src, loff, dst, dst_loff, len);
2939
2940 ret = extent_same_check_offsets(src, loff, len);
2941 if (ret)
2942 goto out_unlock;
2943
2944 ret = extent_same_check_offsets(dst, dst_loff, len);
2945 if (ret)
2946 goto out_unlock;
2947
2948 /* don't make the dst file partly checksummed */
2949 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2950 (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
2951 ret = -EINVAL;
2952 goto out_unlock;
2953 }
2954
2955 ret = btrfs_cmp_data(src, loff, dst, dst_loff, len);
2956 if (ret == 0)
2957 ret = btrfs_clone(src, dst, loff, len, len, dst_loff);
2958
2959 out_unlock:
2960 btrfs_double_unlock(src, loff, dst, dst_loff, len);
2961
2962 return ret;
2963 }
2964
2965 #define BTRFS_MAX_DEDUPE_LEN (16 * 1024 * 1024)
2966
2967 static long btrfs_ioctl_file_extent_same(struct file *file,
2968 struct btrfs_ioctl_same_args __user *argp)
2969 {
2970 struct btrfs_ioctl_same_args *same;
2971 struct btrfs_ioctl_same_extent_info *info;
2972 struct inode *src = file_inode(file);
2973 u64 off;
2974 u64 len;
2975 int i;
2976 int ret;
2977 unsigned long size;
2978 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
2979 bool is_admin = capable(CAP_SYS_ADMIN);
2980 u16 count;
2981
2982 if (!(file->f_mode & FMODE_READ))
2983 return -EINVAL;
2984
2985 ret = mnt_want_write_file(file);
2986 if (ret)
2987 return ret;
2988
2989 if (get_user(count, &argp->dest_count)) {
2990 ret = -EFAULT;
2991 goto out;
2992 }
2993
2994 size = offsetof(struct btrfs_ioctl_same_args __user, info[count]);
2995
2996 same = memdup_user(argp, size);
2997
2998 if (IS_ERR(same)) {
2999 ret = PTR_ERR(same);
3000 goto out;
3001 }
3002
3003 off = same->logical_offset;
3004 len = same->length;
3005
3006 /*
3007 * Limit the total length we will dedupe for each operation.
3008 * This is intended to bound the total time spent in this
3009 * ioctl to something sane.
3010 */
3011 if (len > BTRFS_MAX_DEDUPE_LEN)
3012 len = BTRFS_MAX_DEDUPE_LEN;
3013
3014 if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
3015 /*
3016 * Btrfs does not support blocksize < page_size. As a
3017 * result, btrfs_cmp_data() won't correctly handle
3018 * this situation without an update.
3019 */
3020 ret = -EINVAL;
3021 goto out;
3022 }
3023
3024 ret = -EISDIR;
3025 if (S_ISDIR(src->i_mode))
3026 goto out;
3027
3028 ret = -EACCES;
3029 if (!S_ISREG(src->i_mode))
3030 goto out;
3031
3032 /* pre-format output fields to sane values */
3033 for (i = 0; i < count; i++) {
3034 same->info[i].bytes_deduped = 0ULL;
3035 same->info[i].status = 0;
3036 }
3037
3038 for (i = 0, info = same->info; i < count; i++, info++) {
3039 struct inode *dst;
3040 struct fd dst_file = fdget(info->fd);
3041 if (!dst_file.file) {
3042 info->status = -EBADF;
3043 continue;
3044 }
3045 dst = file_inode(dst_file.file);
3046
3047 if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) {
3048 info->status = -EINVAL;
3049 } else if (file->f_path.mnt != dst_file.file->f_path.mnt) {
3050 info->status = -EXDEV;
3051 } else if (S_ISDIR(dst->i_mode)) {
3052 info->status = -EISDIR;
3053 } else if (!S_ISREG(dst->i_mode)) {
3054 info->status = -EACCES;
3055 } else {
3056 info->status = btrfs_extent_same(src, off, len, dst,
3057 info->logical_offset);
3058 if (info->status == 0)
3059 info->bytes_deduped += len;
3060 }
3061 fdput(dst_file);
3062 }
3063
3064 ret = copy_to_user(argp, same, size);
3065 if (ret)
3066 ret = -EFAULT;
3067
3068 out:
3069 mnt_drop_write_file(file);
3070 return ret;
3071 }
3072
3073 /* Helper to check and see if this root currently has a ref on the given disk
3074 * bytenr. If it does then we need to update the quota for this root. This
3075 * doesn't do anything if quotas aren't enabled.
3076 */
3077 static int check_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3078 u64 disko)
3079 {
3080 struct seq_list tree_mod_seq_elem = {};
3081 struct ulist *roots;
3082 struct ulist_iterator uiter;
3083 struct ulist_node *root_node = NULL;
3084 int ret;
3085
3086 if (!root->fs_info->quota_enabled)
3087 return 1;
3088
3089 btrfs_get_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3090 ret = btrfs_find_all_roots(trans, root->fs_info, disko,
3091 tree_mod_seq_elem.seq, &roots);
3092 if (ret < 0)
3093 goto out;
3094 ret = 0;
3095 ULIST_ITER_INIT(&uiter);
3096 while ((root_node = ulist_next(roots, &uiter))) {
3097 if (root_node->val == root->objectid) {
3098 ret = 1;
3099 break;
3100 }
3101 }
3102 ulist_free(roots);
3103 out:
3104 btrfs_put_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3105 return ret;
3106 }
3107
3108 static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3109 struct inode *inode,
3110 u64 endoff,
3111 const u64 destoff,
3112 const u64 olen)
3113 {
3114 struct btrfs_root *root = BTRFS_I(inode)->root;
3115 int ret;
3116
3117 inode_inc_iversion(inode);
3118 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3119 /*
3120 * We round up to the block size at eof when determining which
3121 * extents to clone above, but shouldn't round up the file size.
3122 */
3123 if (endoff > destoff + olen)
3124 endoff = destoff + olen;
3125 if (endoff > inode->i_size)
3126 btrfs_i_size_write(inode, endoff);
3127
3128 ret = btrfs_update_inode(trans, root, inode);
3129 if (ret) {
3130 btrfs_abort_transaction(trans, root, ret);
3131 btrfs_end_transaction(trans, root);
3132 goto out;
3133 }
3134 ret = btrfs_end_transaction(trans, root);
3135 out:
3136 return ret;
3137 }
3138
3139 static void clone_update_extent_map(struct inode *inode,
3140 const struct btrfs_trans_handle *trans,
3141 const struct btrfs_path *path,
3142 struct btrfs_file_extent_item *fi,
3143 const u64 hole_offset,
3144 const u64 hole_len)
3145 {
3146 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
3147 struct extent_map *em;
3148 int ret;
3149
3150 em = alloc_extent_map();
3151 if (!em) {
3152 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3153 &BTRFS_I(inode)->runtime_flags);
3154 return;
3155 }
3156
3157 if (fi) {
3158 btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
3159 em->generation = -1;
3160 if (btrfs_file_extent_type(path->nodes[0], fi) ==
3161 BTRFS_FILE_EXTENT_INLINE)
3162 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3163 &BTRFS_I(inode)->runtime_flags);
3164 } else {
3165 em->start = hole_offset;
3166 em->len = hole_len;
3167 em->ram_bytes = em->len;
3168 em->orig_start = hole_offset;
3169 em->block_start = EXTENT_MAP_HOLE;
3170 em->block_len = 0;
3171 em->orig_block_len = 0;
3172 em->compress_type = BTRFS_COMPRESS_NONE;
3173 em->generation = trans->transid;
3174 }
3175
3176 while (1) {
3177 write_lock(&em_tree->lock);
3178 ret = add_extent_mapping(em_tree, em, 1);
3179 write_unlock(&em_tree->lock);
3180 if (ret != -EEXIST) {
3181 free_extent_map(em);
3182 break;
3183 }
3184 btrfs_drop_extent_cache(inode, em->start,
3185 em->start + em->len - 1, 0);
3186 }
3187
3188 if (unlikely(ret))
3189 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3190 &BTRFS_I(inode)->runtime_flags);
3191 }
3192
3193 /**
3194 * btrfs_clone() - clone a range from inode file to another
3195 *
3196 * @src: Inode to clone from
3197 * @inode: Inode to clone to
3198 * @off: Offset within source to start clone from
3199 * @olen: Original length, passed by user, of range to clone
3200 * @olen_aligned: Block-aligned value of olen, extent_same uses
3201 * identical values here
3202 * @destoff: Offset within @inode to start clone
3203 */
3204 static int btrfs_clone(struct inode *src, struct inode *inode,
3205 const u64 off, const u64 olen, const u64 olen_aligned,
3206 const u64 destoff)
3207 {
3208 struct btrfs_root *root = BTRFS_I(inode)->root;
3209 struct btrfs_path *path = NULL;
3210 struct extent_buffer *leaf;
3211 struct btrfs_trans_handle *trans;
3212 char *buf = NULL;
3213 struct btrfs_key key;
3214 u32 nritems;
3215 int slot;
3216 int ret;
3217 int no_quota;
3218 const u64 len = olen_aligned;
3219 u64 last_disko = 0;
3220 u64 last_dest_end = destoff;
3221
3222 ret = -ENOMEM;
3223 buf = vmalloc(btrfs_level_size(root, 0));
3224 if (!buf)
3225 return ret;
3226
3227 path = btrfs_alloc_path();
3228 if (!path) {
3229 vfree(buf);
3230 return ret;
3231 }
3232
3233 path->reada = 2;
3234 /* clone data */
3235 key.objectid = btrfs_ino(src);
3236 key.type = BTRFS_EXTENT_DATA_KEY;
3237 key.offset = off;
3238
3239 while (1) {
3240 /*
3241 * note the key will change type as we walk through the
3242 * tree.
3243 */
3244 path->leave_spinning = 1;
3245 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3246 0, 0);
3247 if (ret < 0)
3248 goto out;
3249 /*
3250 * First search, if no extent item that starts at offset off was
3251 * found but the previous item is an extent item, it's possible
3252 * it might overlap our target range, therefore process it.
3253 */
3254 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3255 btrfs_item_key_to_cpu(path->nodes[0], &key,
3256 path->slots[0] - 1);
3257 if (key.type == BTRFS_EXTENT_DATA_KEY)
3258 path->slots[0]--;
3259 }
3260
3261 nritems = btrfs_header_nritems(path->nodes[0]);
3262 process_slot:
3263 no_quota = 1;
3264 if (path->slots[0] >= nritems) {
3265 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3266 if (ret < 0)
3267 goto out;
3268 if (ret > 0)
3269 break;
3270 nritems = btrfs_header_nritems(path->nodes[0]);
3271 }
3272 leaf = path->nodes[0];
3273 slot = path->slots[0];
3274
3275 btrfs_item_key_to_cpu(leaf, &key, slot);
3276 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
3277 key.objectid != btrfs_ino(src))
3278 break;
3279
3280 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
3281 struct btrfs_file_extent_item *extent;
3282 int type;
3283 u32 size;
3284 struct btrfs_key new_key;
3285 u64 disko = 0, diskl = 0;
3286 u64 datao = 0, datal = 0;
3287 u8 comp;
3288 u64 drop_start;
3289
3290 extent = btrfs_item_ptr(leaf, slot,
3291 struct btrfs_file_extent_item);
3292 comp = btrfs_file_extent_compression(leaf, extent);
3293 type = btrfs_file_extent_type(leaf, extent);
3294 if (type == BTRFS_FILE_EXTENT_REG ||
3295 type == BTRFS_FILE_EXTENT_PREALLOC) {
3296 disko = btrfs_file_extent_disk_bytenr(leaf,
3297 extent);
3298 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3299 extent);
3300 datao = btrfs_file_extent_offset(leaf, extent);
3301 datal = btrfs_file_extent_num_bytes(leaf,
3302 extent);
3303 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3304 /* take upper bound, may be compressed */
3305 datal = btrfs_file_extent_ram_bytes(leaf,
3306 extent);
3307 }
3308
3309 /*
3310 * The first search might have left us at an extent
3311 * item that ends before our target range's start, can
3312 * happen if we have holes and NO_HOLES feature enabled.
3313 */
3314 if (key.offset + datal <= off) {
3315 path->slots[0]++;
3316 goto process_slot;
3317 } else if (key.offset >= off + len) {
3318 break;
3319 }
3320
3321 size = btrfs_item_size_nr(leaf, slot);
3322 read_extent_buffer(leaf, buf,
3323 btrfs_item_ptr_offset(leaf, slot),
3324 size);
3325
3326 btrfs_release_path(path);
3327 path->leave_spinning = 0;
3328
3329 memcpy(&new_key, &key, sizeof(new_key));
3330 new_key.objectid = btrfs_ino(inode);
3331 if (off <= key.offset)
3332 new_key.offset = key.offset + destoff - off;
3333 else
3334 new_key.offset = destoff;
3335
3336 /*
3337 * Deal with a hole that doesn't have an extent item
3338 * that represents it (NO_HOLES feature enabled).
3339 * This hole is either in the middle of the cloning
3340 * range or at the beginning (fully overlaps it or
3341 * partially overlaps it).
3342 */
3343 if (new_key.offset != last_dest_end)
3344 drop_start = last_dest_end;
3345 else
3346 drop_start = new_key.offset;
3347
3348 /*
3349 * 1 - adjusting old extent (we may have to split it)
3350 * 1 - add new extent
3351 * 1 - inode update
3352 */
3353 trans = btrfs_start_transaction(root, 3);
3354 if (IS_ERR(trans)) {
3355 ret = PTR_ERR(trans);
3356 goto out;
3357 }
3358
3359 if (type == BTRFS_FILE_EXTENT_REG ||
3360 type == BTRFS_FILE_EXTENT_PREALLOC) {
3361 /*
3362 * a | --- range to clone ---| b
3363 * | ------------- extent ------------- |
3364 */
3365
3366 /* subtract range b */
3367 if (key.offset + datal > off + len)
3368 datal = off + len - key.offset;
3369
3370 /* subtract range a */
3371 if (off > key.offset) {
3372 datao += off - key.offset;
3373 datal -= off - key.offset;
3374 }
3375
3376 ret = btrfs_drop_extents(trans, root, inode,
3377 drop_start,
3378 new_key.offset + datal,
3379 1);
3380 if (ret) {
3381 if (ret != -EOPNOTSUPP)
3382 btrfs_abort_transaction(trans,
3383 root, ret);
3384 btrfs_end_transaction(trans, root);
3385 goto out;
3386 }
3387
3388 ret = btrfs_insert_empty_item(trans, root, path,
3389 &new_key, size);
3390 if (ret) {
3391 btrfs_abort_transaction(trans, root,
3392 ret);
3393 btrfs_end_transaction(trans, root);
3394 goto out;
3395 }
3396
3397 leaf = path->nodes[0];
3398 slot = path->slots[0];
3399 write_extent_buffer(leaf, buf,
3400 btrfs_item_ptr_offset(leaf, slot),
3401 size);
3402
3403 extent = btrfs_item_ptr(leaf, slot,
3404 struct btrfs_file_extent_item);
3405
3406 /* disko == 0 means it's a hole */
3407 if (!disko)
3408 datao = 0;
3409
3410 btrfs_set_file_extent_offset(leaf, extent,
3411 datao);
3412 btrfs_set_file_extent_num_bytes(leaf, extent,
3413 datal);
3414
3415 /*
3416 * We need to look up the roots that point at
3417 * this bytenr and see if the new root does. If
3418 * it does not we need to make sure we update
3419 * quotas appropriately.
3420 */
3421 if (disko && root != BTRFS_I(src)->root &&
3422 disko != last_disko) {
3423 no_quota = check_ref(trans, root,
3424 disko);
3425 if (no_quota < 0) {
3426 btrfs_abort_transaction(trans,
3427 root,
3428 ret);
3429 btrfs_end_transaction(trans,
3430 root);
3431 ret = no_quota;
3432 goto out;
3433 }
3434 }
3435
3436 if (disko) {
3437 inode_add_bytes(inode, datal);
3438 ret = btrfs_inc_extent_ref(trans, root,
3439 disko, diskl, 0,
3440 root->root_key.objectid,
3441 btrfs_ino(inode),
3442 new_key.offset - datao,
3443 no_quota);
3444 if (ret) {
3445 btrfs_abort_transaction(trans,
3446 root,
3447 ret);
3448 btrfs_end_transaction(trans,
3449 root);
3450 goto out;
3451
3452 }
3453 }
3454 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3455 u64 skip = 0;
3456 u64 trim = 0;
3457 u64 aligned_end = 0;
3458
3459 if (off > key.offset) {
3460 skip = off - key.offset;
3461 new_key.offset += skip;
3462 }
3463
3464 if (key.offset + datal > off + len)
3465 trim = key.offset + datal - (off + len);
3466
3467 if (comp && (skip || trim)) {
3468 ret = -EINVAL;
3469 btrfs_end_transaction(trans, root);
3470 goto out;
3471 }
3472 size -= skip + trim;
3473 datal -= skip + trim;
3474
3475 aligned_end = ALIGN(new_key.offset + datal,
3476 root->sectorsize);
3477 ret = btrfs_drop_extents(trans, root, inode,
3478 drop_start,
3479 aligned_end,
3480 1);
3481 if (ret) {
3482 if (ret != -EOPNOTSUPP)
3483 btrfs_abort_transaction(trans,
3484 root, ret);
3485 btrfs_end_transaction(trans, root);
3486 goto out;
3487 }
3488
3489 ret = btrfs_insert_empty_item(trans, root, path,
3490 &new_key, size);
3491 if (ret) {
3492 btrfs_abort_transaction(trans, root,
3493 ret);
3494 btrfs_end_transaction(trans, root);
3495 goto out;
3496 }
3497
3498 if (skip) {
3499 u32 start =
3500 btrfs_file_extent_calc_inline_size(0);
3501 memmove(buf+start, buf+start+skip,
3502 datal);
3503 }
3504
3505 leaf = path->nodes[0];
3506 slot = path->slots[0];
3507 write_extent_buffer(leaf, buf,
3508 btrfs_item_ptr_offset(leaf, slot),
3509 size);
3510 inode_add_bytes(inode, datal);
3511 extent = btrfs_item_ptr(leaf, slot,
3512 struct btrfs_file_extent_item);
3513 }
3514
3515 /* If we have an implicit hole (NO_HOLES feature). */
3516 if (drop_start < new_key.offset)
3517 clone_update_extent_map(inode, trans,
3518 path, NULL, drop_start,
3519 new_key.offset - drop_start);
3520
3521 clone_update_extent_map(inode, trans, path,
3522 extent, 0, 0);
3523
3524 btrfs_mark_buffer_dirty(leaf);
3525 btrfs_release_path(path);
3526
3527 last_dest_end = new_key.offset + datal;
3528 ret = clone_finish_inode_update(trans, inode,
3529 last_dest_end,
3530 destoff, olen);
3531 if (ret)
3532 goto out;
3533 if (new_key.offset + datal >= destoff + len)
3534 break;
3535 }
3536 btrfs_release_path(path);
3537 key.offset++;
3538 }
3539 ret = 0;
3540
3541 if (last_dest_end < destoff + len) {
3542 /*
3543 * We have an implicit hole (NO_HOLES feature is enabled) that
3544 * fully or partially overlaps our cloning range at its end.
3545 */
3546 btrfs_release_path(path);
3547
3548 /*
3549 * 1 - remove extent(s)
3550 * 1 - inode update
3551 */
3552 trans = btrfs_start_transaction(root, 2);
3553 if (IS_ERR(trans)) {
3554 ret = PTR_ERR(trans);
3555 goto out;
3556 }
3557 ret = btrfs_drop_extents(trans, root, inode,
3558 last_dest_end, destoff + len, 1);
3559 if (ret) {
3560 if (ret != -EOPNOTSUPP)
3561 btrfs_abort_transaction(trans, root, ret);
3562 btrfs_end_transaction(trans, root);
3563 goto out;
3564 }
3565 ret = clone_finish_inode_update(trans, inode, destoff + len,
3566 destoff, olen);
3567 if (ret)
3568 goto out;
3569 clone_update_extent_map(inode, trans, path, NULL, last_dest_end,
3570 destoff + len - last_dest_end);
3571 }
3572
3573 out:
3574 btrfs_free_path(path);
3575 vfree(buf);
3576 return ret;
3577 }
3578
3579 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
3580 u64 off, u64 olen, u64 destoff)
3581 {
3582 struct inode *inode = file_inode(file);
3583 struct btrfs_root *root = BTRFS_I(inode)->root;
3584 struct fd src_file;
3585 struct inode *src;
3586 int ret;
3587 u64 len = olen;
3588 u64 bs = root->fs_info->sb->s_blocksize;
3589 int same_inode = 0;
3590
3591 /*
3592 * TODO:
3593 * - split compressed inline extents. annoying: we need to
3594 * decompress into destination's address_space (the file offset
3595 * may change, so source mapping won't do), then recompress (or
3596 * otherwise reinsert) a subrange.
3597 *
3598 * - split destination inode's inline extents. The inline extents can
3599 * be either compressed or non-compressed.
3600 */
3601
3602 /* the destination must be opened for writing */
3603 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
3604 return -EINVAL;
3605
3606 if (btrfs_root_readonly(root))
3607 return -EROFS;
3608
3609 ret = mnt_want_write_file(file);
3610 if (ret)
3611 return ret;
3612
3613 src_file = fdget(srcfd);
3614 if (!src_file.file) {
3615 ret = -EBADF;
3616 goto out_drop_write;
3617 }
3618
3619 ret = -EXDEV;
3620 if (src_file.file->f_path.mnt != file->f_path.mnt)
3621 goto out_fput;
3622
3623 src = file_inode(src_file.file);
3624
3625 ret = -EINVAL;
3626 if (src == inode)
3627 same_inode = 1;
3628
3629 /* the src must be open for reading */
3630 if (!(src_file.file->f_mode & FMODE_READ))
3631 goto out_fput;
3632
3633 /* don't make the dst file partly checksummed */
3634 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3635 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3636 goto out_fput;
3637
3638 ret = -EISDIR;
3639 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3640 goto out_fput;
3641
3642 ret = -EXDEV;
3643 if (src->i_sb != inode->i_sb)
3644 goto out_fput;
3645
3646 if (!same_inode) {
3647 if (inode < src) {
3648 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
3649 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
3650 } else {
3651 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
3652 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
3653 }
3654 } else {
3655 mutex_lock(&src->i_mutex);
3656 }
3657
3658 /* determine range to clone */
3659 ret = -EINVAL;
3660 if (off + len > src->i_size || off + len < off)
3661 goto out_unlock;
3662 if (len == 0)
3663 olen = len = src->i_size - off;
3664 /* if we extend to eof, continue to block boundary */
3665 if (off + len == src->i_size)
3666 len = ALIGN(src->i_size, bs) - off;
3667
3668 /* verify the end result is block aligned */
3669 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
3670 !IS_ALIGNED(destoff, bs))
3671 goto out_unlock;
3672
3673 /* verify if ranges are overlapped within the same file */
3674 if (same_inode) {
3675 if (destoff + len > off && destoff < off + len)
3676 goto out_unlock;
3677 }
3678
3679 if (destoff > inode->i_size) {
3680 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3681 if (ret)
3682 goto out_unlock;
3683 }
3684
3685 /*
3686 * Lock the target range too. Right after we replace the file extent
3687 * items in the fs tree (which now point to the cloned data), we might
3688 * have a worker replace them with extent items relative to a write
3689 * operation that was issued before this clone operation (i.e. confront
3690 * with inode.c:btrfs_finish_ordered_io).
3691 */
3692 if (same_inode) {
3693 u64 lock_start = min_t(u64, off, destoff);
3694 u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
3695
3696 lock_extent_range(src, lock_start, lock_len);
3697 } else {
3698 lock_extent_range(src, off, len);
3699 lock_extent_range(inode, destoff, len);
3700 }
3701
3702 ret = btrfs_clone(src, inode, off, olen, len, destoff);
3703
3704 if (same_inode) {
3705 u64 lock_start = min_t(u64, off, destoff);
3706 u64 lock_end = max_t(u64, off, destoff) + len - 1;
3707
3708 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
3709 } else {
3710 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
3711 unlock_extent(&BTRFS_I(inode)->io_tree, destoff,
3712 destoff + len - 1);
3713 }
3714 /*
3715 * Truncate page cache pages so that future reads will see the cloned
3716 * data immediately and not the previous data.
3717 */
3718 truncate_inode_pages_range(&inode->i_data, destoff,
3719 PAGE_CACHE_ALIGN(destoff + len) - 1);
3720 out_unlock:
3721 if (!same_inode) {
3722 if (inode < src) {
3723 mutex_unlock(&src->i_mutex);
3724 mutex_unlock(&inode->i_mutex);
3725 } else {
3726 mutex_unlock(&inode->i_mutex);
3727 mutex_unlock(&src->i_mutex);
3728 }
3729 } else {
3730 mutex_unlock(&src->i_mutex);
3731 }
3732 out_fput:
3733 fdput(src_file);
3734 out_drop_write:
3735 mnt_drop_write_file(file);
3736 return ret;
3737 }
3738
3739 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3740 {
3741 struct btrfs_ioctl_clone_range_args args;
3742
3743 if (copy_from_user(&args, argp, sizeof(args)))
3744 return -EFAULT;
3745 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
3746 args.src_length, args.dest_offset);
3747 }
3748
3749 /*
3750 * there are many ways the trans_start and trans_end ioctls can lead
3751 * to deadlocks. They should only be used by applications that
3752 * basically own the machine, and have a very in depth understanding
3753 * of all the possible deadlocks and enospc problems.
3754 */
3755 static long btrfs_ioctl_trans_start(struct file *file)
3756 {
3757 struct inode *inode = file_inode(file);
3758 struct btrfs_root *root = BTRFS_I(inode)->root;
3759 struct btrfs_trans_handle *trans;
3760 int ret;
3761
3762 ret = -EPERM;
3763 if (!capable(CAP_SYS_ADMIN))
3764 goto out;
3765
3766 ret = -EINPROGRESS;
3767 if (file->private_data)
3768 goto out;
3769
3770 ret = -EROFS;
3771 if (btrfs_root_readonly(root))
3772 goto out;
3773
3774 ret = mnt_want_write_file(file);
3775 if (ret)
3776 goto out;
3777
3778 atomic_inc(&root->fs_info->open_ioctl_trans);
3779
3780 ret = -ENOMEM;
3781 trans = btrfs_start_ioctl_transaction(root);
3782 if (IS_ERR(trans))
3783 goto out_drop;
3784
3785 file->private_data = trans;
3786 return 0;
3787
3788 out_drop:
3789 atomic_dec(&root->fs_info->open_ioctl_trans);
3790 mnt_drop_write_file(file);
3791 out:
3792 return ret;
3793 }
3794
3795 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3796 {
3797 struct inode *inode = file_inode(file);
3798 struct btrfs_root *root = BTRFS_I(inode)->root;
3799 struct btrfs_root *new_root;
3800 struct btrfs_dir_item *di;
3801 struct btrfs_trans_handle *trans;
3802 struct btrfs_path *path;
3803 struct btrfs_key location;
3804 struct btrfs_disk_key disk_key;
3805 u64 objectid = 0;
3806 u64 dir_id;
3807 int ret;
3808
3809 if (!capable(CAP_SYS_ADMIN))
3810 return -EPERM;
3811
3812 ret = mnt_want_write_file(file);
3813 if (ret)
3814 return ret;
3815
3816 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3817 ret = -EFAULT;
3818 goto out;
3819 }
3820
3821 if (!objectid)
3822 objectid = BTRFS_FS_TREE_OBJECTID;
3823
3824 location.objectid = objectid;
3825 location.type = BTRFS_ROOT_ITEM_KEY;
3826 location.offset = (u64)-1;
3827
3828 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
3829 if (IS_ERR(new_root)) {
3830 ret = PTR_ERR(new_root);
3831 goto out;
3832 }
3833
3834 path = btrfs_alloc_path();
3835 if (!path) {
3836 ret = -ENOMEM;
3837 goto out;
3838 }
3839 path->leave_spinning = 1;
3840
3841 trans = btrfs_start_transaction(root, 1);
3842 if (IS_ERR(trans)) {
3843 btrfs_free_path(path);
3844 ret = PTR_ERR(trans);
3845 goto out;
3846 }
3847
3848 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3849 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
3850 dir_id, "default", 7, 1);
3851 if (IS_ERR_OR_NULL(di)) {
3852 btrfs_free_path(path);
3853 btrfs_end_transaction(trans, root);
3854 btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
3855 "item, this isn't going to work");
3856 ret = -ENOENT;
3857 goto out;
3858 }
3859
3860 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3861 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3862 btrfs_mark_buffer_dirty(path->nodes[0]);
3863 btrfs_free_path(path);
3864
3865 btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
3866 btrfs_end_transaction(trans, root);
3867 out:
3868 mnt_drop_write_file(file);
3869 return ret;
3870 }
3871
3872 void btrfs_get_block_group_info(struct list_head *groups_list,
3873 struct btrfs_ioctl_space_info *space)
3874 {
3875 struct btrfs_block_group_cache *block_group;
3876
3877 space->total_bytes = 0;
3878 space->used_bytes = 0;
3879 space->flags = 0;
3880 list_for_each_entry(block_group, groups_list, list) {
3881 space->flags = block_group->flags;
3882 space->total_bytes += block_group->key.offset;
3883 space->used_bytes +=
3884 btrfs_block_group_used(&block_group->item);
3885 }
3886 }
3887
3888 static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
3889 {
3890 struct btrfs_ioctl_space_args space_args;
3891 struct btrfs_ioctl_space_info space;
3892 struct btrfs_ioctl_space_info *dest;
3893 struct btrfs_ioctl_space_info *dest_orig;
3894 struct btrfs_ioctl_space_info __user *user_dest;
3895 struct btrfs_space_info *info;
3896 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3897 BTRFS_BLOCK_GROUP_SYSTEM,
3898 BTRFS_BLOCK_GROUP_METADATA,
3899 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3900 int num_types = 4;
3901 int alloc_size;
3902 int ret = 0;
3903 u64 slot_count = 0;
3904 int i, c;
3905
3906 if (copy_from_user(&space_args,
3907 (struct btrfs_ioctl_space_args __user *)arg,
3908 sizeof(space_args)))
3909 return -EFAULT;
3910
3911 for (i = 0; i < num_types; i++) {
3912 struct btrfs_space_info *tmp;
3913
3914 info = NULL;
3915 rcu_read_lock();
3916 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3917 list) {
3918 if (tmp->flags == types[i]) {
3919 info = tmp;
3920 break;
3921 }
3922 }
3923 rcu_read_unlock();
3924
3925 if (!info)
3926 continue;
3927
3928 down_read(&info->groups_sem);
3929 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3930 if (!list_empty(&info->block_groups[c]))
3931 slot_count++;
3932 }
3933 up_read(&info->groups_sem);
3934 }
3935
3936 /*
3937 * Global block reserve, exported as a space_info
3938 */
3939 slot_count++;
3940
3941 /* space_slots == 0 means they are asking for a count */
3942 if (space_args.space_slots == 0) {
3943 space_args.total_spaces = slot_count;
3944 goto out;
3945 }
3946
3947 slot_count = min_t(u64, space_args.space_slots, slot_count);
3948
3949 alloc_size = sizeof(*dest) * slot_count;
3950
3951 /* we generally have at most 6 or so space infos, one for each raid
3952 * level. So, a whole page should be more than enough for everyone
3953 */
3954 if (alloc_size > PAGE_CACHE_SIZE)
3955 return -ENOMEM;
3956
3957 space_args.total_spaces = 0;
3958 dest = kmalloc(alloc_size, GFP_NOFS);
3959 if (!dest)
3960 return -ENOMEM;
3961 dest_orig = dest;
3962
3963 /* now we have a buffer to copy into */
3964 for (i = 0; i < num_types; i++) {
3965 struct btrfs_space_info *tmp;
3966
3967 if (!slot_count)
3968 break;
3969
3970 info = NULL;
3971 rcu_read_lock();
3972 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3973 list) {
3974 if (tmp->flags == types[i]) {
3975 info = tmp;
3976 break;
3977 }
3978 }
3979 rcu_read_unlock();
3980
3981 if (!info)
3982 continue;
3983 down_read(&info->groups_sem);
3984 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3985 if (!list_empty(&info->block_groups[c])) {
3986 btrfs_get_block_group_info(
3987 &info->block_groups[c], &space);
3988 memcpy(dest, &space, sizeof(space));
3989 dest++;
3990 space_args.total_spaces++;
3991 slot_count--;
3992 }
3993 if (!slot_count)
3994 break;
3995 }
3996 up_read(&info->groups_sem);
3997 }
3998
3999 /*
4000 * Add global block reserve
4001 */
4002 if (slot_count) {
4003 struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv;
4004
4005 spin_lock(&block_rsv->lock);
4006 space.total_bytes = block_rsv->size;
4007 space.used_bytes = block_rsv->size - block_rsv->reserved;
4008 spin_unlock(&block_rsv->lock);
4009 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
4010 memcpy(dest, &space, sizeof(space));
4011 space_args.total_spaces++;
4012 }
4013
4014 user_dest = (struct btrfs_ioctl_space_info __user *)
4015 (arg + sizeof(struct btrfs_ioctl_space_args));
4016
4017 if (copy_to_user(user_dest, dest_orig, alloc_size))
4018 ret = -EFAULT;
4019
4020 kfree(dest_orig);
4021 out:
4022 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4023 ret = -EFAULT;
4024
4025 return ret;
4026 }
4027
4028 /*
4029 * there are many ways the trans_start and trans_end ioctls can lead
4030 * to deadlocks. They should only be used by applications that
4031 * basically own the machine, and have a very in depth understanding
4032 * of all the possible deadlocks and enospc problems.
4033 */
4034 long btrfs_ioctl_trans_end(struct file *file)
4035 {
4036 struct inode *inode = file_inode(file);
4037 struct btrfs_root *root = BTRFS_I(inode)->root;
4038 struct btrfs_trans_handle *trans;
4039
4040 trans = file->private_data;
4041 if (!trans)
4042 return -EINVAL;
4043 file->private_data = NULL;
4044
4045 btrfs_end_transaction(trans, root);
4046
4047 atomic_dec(&root->fs_info->open_ioctl_trans);
4048
4049 mnt_drop_write_file(file);
4050 return 0;
4051 }
4052
4053 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4054 void __user *argp)
4055 {
4056 struct btrfs_trans_handle *trans;
4057 u64 transid;
4058 int ret;
4059
4060 trans = btrfs_attach_transaction_barrier(root);
4061 if (IS_ERR(trans)) {
4062 if (PTR_ERR(trans) != -ENOENT)
4063 return PTR_ERR(trans);
4064
4065 /* No running transaction, don't bother */
4066 transid = root->fs_info->last_trans_committed;
4067 goto out;
4068 }
4069 transid = trans->transid;
4070 ret = btrfs_commit_transaction_async(trans, root, 0);
4071 if (ret) {
4072 btrfs_end_transaction(trans, root);
4073 return ret;
4074 }
4075 out:
4076 if (argp)
4077 if (copy_to_user(argp, &transid, sizeof(transid)))
4078 return -EFAULT;
4079 return 0;
4080 }
4081
4082 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
4083 void __user *argp)
4084 {
4085 u64 transid;
4086
4087 if (argp) {
4088 if (copy_from_user(&transid, argp, sizeof(transid)))
4089 return -EFAULT;
4090 } else {
4091 transid = 0; /* current trans */
4092 }
4093 return btrfs_wait_for_commit(root, transid);
4094 }
4095
4096 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4097 {
4098 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4099 struct btrfs_ioctl_scrub_args *sa;
4100 int ret;
4101
4102 if (!capable(CAP_SYS_ADMIN))
4103 return -EPERM;
4104
4105 sa = memdup_user(arg, sizeof(*sa));
4106 if (IS_ERR(sa))
4107 return PTR_ERR(sa);
4108
4109 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4110 ret = mnt_want_write_file(file);
4111 if (ret)
4112 goto out;
4113 }
4114
4115 ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
4116 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4117 0);
4118
4119 if (copy_to_user(arg, sa, sizeof(*sa)))
4120 ret = -EFAULT;
4121
4122 if (!(sa->flags & BTRFS_SCRUB_READONLY))
4123 mnt_drop_write_file(file);
4124 out:
4125 kfree(sa);
4126 return ret;
4127 }
4128
4129 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
4130 {
4131 if (!capable(CAP_SYS_ADMIN))
4132 return -EPERM;
4133
4134 return btrfs_scrub_cancel(root->fs_info);
4135 }
4136
4137 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
4138 void __user *arg)
4139 {
4140 struct btrfs_ioctl_scrub_args *sa;
4141 int ret;
4142
4143 if (!capable(CAP_SYS_ADMIN))
4144 return -EPERM;
4145
4146 sa = memdup_user(arg, sizeof(*sa));
4147 if (IS_ERR(sa))
4148 return PTR_ERR(sa);
4149
4150 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
4151
4152 if (copy_to_user(arg, sa, sizeof(*sa)))
4153 ret = -EFAULT;
4154
4155 kfree(sa);
4156 return ret;
4157 }
4158
4159 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
4160 void __user *arg)
4161 {
4162 struct btrfs_ioctl_get_dev_stats *sa;
4163 int ret;
4164
4165 sa = memdup_user(arg, sizeof(*sa));
4166 if (IS_ERR(sa))
4167 return PTR_ERR(sa);
4168
4169 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4170 kfree(sa);
4171 return -EPERM;
4172 }
4173
4174 ret = btrfs_get_dev_stats(root, sa);
4175
4176 if (copy_to_user(arg, sa, sizeof(*sa)))
4177 ret = -EFAULT;
4178
4179 kfree(sa);
4180 return ret;
4181 }
4182
4183 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
4184 {
4185 struct btrfs_ioctl_dev_replace_args *p;
4186 int ret;
4187
4188 if (!capable(CAP_SYS_ADMIN))
4189 return -EPERM;
4190
4191 p = memdup_user(arg, sizeof(*p));
4192 if (IS_ERR(p))
4193 return PTR_ERR(p);
4194
4195 switch (p->cmd) {
4196 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4197 if (root->fs_info->sb->s_flags & MS_RDONLY) {
4198 ret = -EROFS;
4199 goto out;
4200 }
4201 if (atomic_xchg(
4202 &root->fs_info->mutually_exclusive_operation_running,
4203 1)) {
4204 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4205 } else {
4206 ret = btrfs_dev_replace_start(root, p);
4207 atomic_set(
4208 &root->fs_info->mutually_exclusive_operation_running,
4209 0);
4210 }
4211 break;
4212 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4213 btrfs_dev_replace_status(root->fs_info, p);
4214 ret = 0;
4215 break;
4216 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4217 ret = btrfs_dev_replace_cancel(root->fs_info, p);
4218 break;
4219 default:
4220 ret = -EINVAL;
4221 break;
4222 }
4223
4224 if (copy_to_user(arg, p, sizeof(*p)))
4225 ret = -EFAULT;
4226 out:
4227 kfree(p);
4228 return ret;
4229 }
4230
4231 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4232 {
4233 int ret = 0;
4234 int i;
4235 u64 rel_ptr;
4236 int size;
4237 struct btrfs_ioctl_ino_path_args *ipa = NULL;
4238 struct inode_fs_paths *ipath = NULL;
4239 struct btrfs_path *path;
4240
4241 if (!capable(CAP_DAC_READ_SEARCH))
4242 return -EPERM;
4243
4244 path = btrfs_alloc_path();
4245 if (!path) {
4246 ret = -ENOMEM;
4247 goto out;
4248 }
4249
4250 ipa = memdup_user(arg, sizeof(*ipa));
4251 if (IS_ERR(ipa)) {
4252 ret = PTR_ERR(ipa);
4253 ipa = NULL;
4254 goto out;
4255 }
4256
4257 size = min_t(u32, ipa->size, 4096);
4258 ipath = init_ipath(size, root, path);
4259 if (IS_ERR(ipath)) {
4260 ret = PTR_ERR(ipath);
4261 ipath = NULL;
4262 goto out;
4263 }
4264
4265 ret = paths_from_inode(ipa->inum, ipath);
4266 if (ret < 0)
4267 goto out;
4268
4269 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4270 rel_ptr = ipath->fspath->val[i] -
4271 (u64)(unsigned long)ipath->fspath->val;
4272 ipath->fspath->val[i] = rel_ptr;
4273 }
4274
4275 ret = copy_to_user((void *)(unsigned long)ipa->fspath,
4276 (void *)(unsigned long)ipath->fspath, size);
4277 if (ret) {
4278 ret = -EFAULT;
4279 goto out;
4280 }
4281
4282 out:
4283 btrfs_free_path(path);
4284 free_ipath(ipath);
4285 kfree(ipa);
4286
4287 return ret;
4288 }
4289
4290 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4291 {
4292 struct btrfs_data_container *inodes = ctx;
4293 const size_t c = 3 * sizeof(u64);
4294
4295 if (inodes->bytes_left >= c) {
4296 inodes->bytes_left -= c;
4297 inodes->val[inodes->elem_cnt] = inum;
4298 inodes->val[inodes->elem_cnt + 1] = offset;
4299 inodes->val[inodes->elem_cnt + 2] = root;
4300 inodes->elem_cnt += 3;
4301 } else {
4302 inodes->bytes_missing += c - inodes->bytes_left;
4303 inodes->bytes_left = 0;
4304 inodes->elem_missed += 3;
4305 }
4306
4307 return 0;
4308 }
4309
4310 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
4311 void __user *arg)
4312 {
4313 int ret = 0;
4314 int size;
4315 struct btrfs_ioctl_logical_ino_args *loi;
4316 struct btrfs_data_container *inodes = NULL;
4317 struct btrfs_path *path = NULL;
4318
4319 if (!capable(CAP_SYS_ADMIN))
4320 return -EPERM;
4321
4322 loi = memdup_user(arg, sizeof(*loi));
4323 if (IS_ERR(loi)) {
4324 ret = PTR_ERR(loi);
4325 loi = NULL;
4326 goto out;
4327 }
4328
4329 path = btrfs_alloc_path();
4330 if (!path) {
4331 ret = -ENOMEM;
4332 goto out;
4333 }
4334
4335 size = min_t(u32, loi->size, 64 * 1024);
4336 inodes = init_data_container(size);
4337 if (IS_ERR(inodes)) {
4338 ret = PTR_ERR(inodes);
4339 inodes = NULL;
4340 goto out;
4341 }
4342
4343 ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
4344 build_ino_list, inodes);
4345 if (ret == -EINVAL)
4346 ret = -ENOENT;
4347 if (ret < 0)
4348 goto out;
4349
4350 ret = copy_to_user((void *)(unsigned long)loi->inodes,
4351 (void *)(unsigned long)inodes, size);
4352 if (ret)
4353 ret = -EFAULT;
4354
4355 out:
4356 btrfs_free_path(path);
4357 vfree(inodes);
4358 kfree(loi);
4359
4360 return ret;
4361 }
4362
4363 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
4364 struct btrfs_ioctl_balance_args *bargs)
4365 {
4366 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4367
4368 bargs->flags = bctl->flags;
4369
4370 if (atomic_read(&fs_info->balance_running))
4371 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4372 if (atomic_read(&fs_info->balance_pause_req))
4373 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4374 if (atomic_read(&fs_info->balance_cancel_req))
4375 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4376
4377 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4378 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4379 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4380
4381 if (lock) {
4382 spin_lock(&fs_info->balance_lock);
4383 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4384 spin_unlock(&fs_info->balance_lock);
4385 } else {
4386 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4387 }
4388 }
4389
4390 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4391 {
4392 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4393 struct btrfs_fs_info *fs_info = root->fs_info;
4394 struct btrfs_ioctl_balance_args *bargs;
4395 struct btrfs_balance_control *bctl;
4396 bool need_unlock; /* for mut. excl. ops lock */
4397 int ret;
4398
4399 if (!capable(CAP_SYS_ADMIN))
4400 return -EPERM;
4401
4402 ret = mnt_want_write_file(file);
4403 if (ret)
4404 return ret;
4405
4406 again:
4407 if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
4408 mutex_lock(&fs_info->volume_mutex);
4409 mutex_lock(&fs_info->balance_mutex);
4410 need_unlock = true;
4411 goto locked;
4412 }
4413
4414 /*
4415 * mut. excl. ops lock is locked. Three possibilites:
4416 * (1) some other op is running
4417 * (2) balance is running
4418 * (3) balance is paused -- special case (think resume)
4419 */
4420 mutex_lock(&fs_info->balance_mutex);
4421 if (fs_info->balance_ctl) {
4422 /* this is either (2) or (3) */
4423 if (!atomic_read(&fs_info->balance_running)) {
4424 mutex_unlock(&fs_info->balance_mutex);
4425 if (!mutex_trylock(&fs_info->volume_mutex))
4426 goto again;
4427 mutex_lock(&fs_info->balance_mutex);
4428
4429 if (fs_info->balance_ctl &&
4430 !atomic_read(&fs_info->balance_running)) {
4431 /* this is (3) */
4432 need_unlock = false;
4433 goto locked;
4434 }
4435
4436 mutex_unlock(&fs_info->balance_mutex);
4437 mutex_unlock(&fs_info->volume_mutex);
4438 goto again;
4439 } else {
4440 /* this is (2) */
4441 mutex_unlock(&fs_info->balance_mutex);
4442 ret = -EINPROGRESS;
4443 goto out;
4444 }
4445 } else {
4446 /* this is (1) */
4447 mutex_unlock(&fs_info->balance_mutex);
4448 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4449 goto out;
4450 }
4451
4452 locked:
4453 BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4454
4455 if (arg) {
4456 bargs = memdup_user(arg, sizeof(*bargs));
4457 if (IS_ERR(bargs)) {
4458 ret = PTR_ERR(bargs);
4459 goto out_unlock;
4460 }
4461
4462 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4463 if (!fs_info->balance_ctl) {
4464 ret = -ENOTCONN;
4465 goto out_bargs;
4466 }
4467
4468 bctl = fs_info->balance_ctl;
4469 spin_lock(&fs_info->balance_lock);
4470 bctl->flags |= BTRFS_BALANCE_RESUME;
4471 spin_unlock(&fs_info->balance_lock);
4472
4473 goto do_balance;
4474 }
4475 } else {
4476 bargs = NULL;
4477 }
4478
4479 if (fs_info->balance_ctl) {
4480 ret = -EINPROGRESS;
4481 goto out_bargs;
4482 }
4483
4484 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
4485 if (!bctl) {
4486 ret = -ENOMEM;
4487 goto out_bargs;
4488 }
4489
4490 bctl->fs_info = fs_info;
4491 if (arg) {
4492 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4493 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4494 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4495
4496 bctl->flags = bargs->flags;
4497 } else {
4498 /* balance everything - no filters */
4499 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4500 }
4501
4502 do_balance:
4503 /*
4504 * Ownership of bctl and mutually_exclusive_operation_running
4505 * goes to to btrfs_balance. bctl is freed in __cancel_balance,
4506 * or, if restriper was paused all the way until unmount, in
4507 * free_fs_info. mutually_exclusive_operation_running is
4508 * cleared in __cancel_balance.
4509 */
4510 need_unlock = false;
4511
4512 ret = btrfs_balance(bctl, bargs);
4513
4514 if (arg) {
4515 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4516 ret = -EFAULT;
4517 }
4518
4519 out_bargs:
4520 kfree(bargs);
4521 out_unlock:
4522 mutex_unlock(&fs_info->balance_mutex);
4523 mutex_unlock(&fs_info->volume_mutex);
4524 if (need_unlock)
4525 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
4526 out:
4527 mnt_drop_write_file(file);
4528 return ret;
4529 }
4530
4531 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
4532 {
4533 if (!capable(CAP_SYS_ADMIN))
4534 return -EPERM;
4535
4536 switch (cmd) {
4537 case BTRFS_BALANCE_CTL_PAUSE:
4538 return btrfs_pause_balance(root->fs_info);
4539 case BTRFS_BALANCE_CTL_CANCEL:
4540 return btrfs_cancel_balance(root->fs_info);
4541 }
4542
4543 return -EINVAL;
4544 }
4545
4546 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
4547 void __user *arg)
4548 {
4549 struct btrfs_fs_info *fs_info = root->fs_info;
4550 struct btrfs_ioctl_balance_args *bargs;
4551 int ret = 0;
4552
4553 if (!capable(CAP_SYS_ADMIN))
4554 return -EPERM;
4555
4556 mutex_lock(&fs_info->balance_mutex);
4557 if (!fs_info->balance_ctl) {
4558 ret = -ENOTCONN;
4559 goto out;
4560 }
4561
4562 bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
4563 if (!bargs) {
4564 ret = -ENOMEM;
4565 goto out;
4566 }
4567
4568 update_ioctl_balance_args(fs_info, 1, bargs);
4569
4570 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4571 ret = -EFAULT;
4572
4573 kfree(bargs);
4574 out:
4575 mutex_unlock(&fs_info->balance_mutex);
4576 return ret;
4577 }
4578
4579 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4580 {
4581 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4582 struct btrfs_ioctl_quota_ctl_args *sa;
4583 struct btrfs_trans_handle *trans = NULL;
4584 int ret;
4585 int err;
4586
4587 if (!capable(CAP_SYS_ADMIN))
4588 return -EPERM;
4589
4590 ret = mnt_want_write_file(file);
4591 if (ret)
4592 return ret;
4593
4594 sa = memdup_user(arg, sizeof(*sa));
4595 if (IS_ERR(sa)) {
4596 ret = PTR_ERR(sa);
4597 goto drop_write;
4598 }
4599
4600 down_write(&root->fs_info->subvol_sem);
4601 trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
4602 if (IS_ERR(trans)) {
4603 ret = PTR_ERR(trans);
4604 goto out;
4605 }
4606
4607 switch (sa->cmd) {
4608 case BTRFS_QUOTA_CTL_ENABLE:
4609 ret = btrfs_quota_enable(trans, root->fs_info);
4610 break;
4611 case BTRFS_QUOTA_CTL_DISABLE:
4612 ret = btrfs_quota_disable(trans, root->fs_info);
4613 break;
4614 default:
4615 ret = -EINVAL;
4616 break;
4617 }
4618
4619 err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
4620 if (err && !ret)
4621 ret = err;
4622 out:
4623 kfree(sa);
4624 up_write(&root->fs_info->subvol_sem);
4625 drop_write:
4626 mnt_drop_write_file(file);
4627 return ret;
4628 }
4629
4630 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4631 {
4632 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4633 struct btrfs_ioctl_qgroup_assign_args *sa;
4634 struct btrfs_trans_handle *trans;
4635 int ret;
4636 int err;
4637
4638 if (!capable(CAP_SYS_ADMIN))
4639 return -EPERM;
4640
4641 ret = mnt_want_write_file(file);
4642 if (ret)
4643 return ret;
4644
4645 sa = memdup_user(arg, sizeof(*sa));
4646 if (IS_ERR(sa)) {
4647 ret = PTR_ERR(sa);
4648 goto drop_write;
4649 }
4650
4651 trans = btrfs_join_transaction(root);
4652 if (IS_ERR(trans)) {
4653 ret = PTR_ERR(trans);
4654 goto out;
4655 }
4656
4657 /* FIXME: check if the IDs really exist */
4658 if (sa->assign) {
4659 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
4660 sa->src, sa->dst);
4661 } else {
4662 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
4663 sa->src, sa->dst);
4664 }
4665
4666 err = btrfs_end_transaction(trans, root);
4667 if (err && !ret)
4668 ret = err;
4669
4670 out:
4671 kfree(sa);
4672 drop_write:
4673 mnt_drop_write_file(file);
4674 return ret;
4675 }
4676
4677 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4678 {
4679 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4680 struct btrfs_ioctl_qgroup_create_args *sa;
4681 struct btrfs_trans_handle *trans;
4682 int ret;
4683 int err;
4684
4685 if (!capable(CAP_SYS_ADMIN))
4686 return -EPERM;
4687
4688 ret = mnt_want_write_file(file);
4689 if (ret)
4690 return ret;
4691
4692 sa = memdup_user(arg, sizeof(*sa));
4693 if (IS_ERR(sa)) {
4694 ret = PTR_ERR(sa);
4695 goto drop_write;
4696 }
4697
4698 if (!sa->qgroupid) {
4699 ret = -EINVAL;
4700 goto out;
4701 }
4702
4703 trans = btrfs_join_transaction(root);
4704 if (IS_ERR(trans)) {
4705 ret = PTR_ERR(trans);
4706 goto out;
4707 }
4708
4709 /* FIXME: check if the IDs really exist */
4710 if (sa->create) {
4711 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
4712 NULL);
4713 } else {
4714 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
4715 }
4716
4717 err = btrfs_end_transaction(trans, root);
4718 if (err && !ret)
4719 ret = err;
4720
4721 out:
4722 kfree(sa);
4723 drop_write:
4724 mnt_drop_write_file(file);
4725 return ret;
4726 }
4727
4728 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4729 {
4730 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4731 struct btrfs_ioctl_qgroup_limit_args *sa;
4732 struct btrfs_trans_handle *trans;
4733 int ret;
4734 int err;
4735 u64 qgroupid;
4736
4737 if (!capable(CAP_SYS_ADMIN))
4738 return -EPERM;
4739
4740 ret = mnt_want_write_file(file);
4741 if (ret)
4742 return ret;
4743
4744 sa = memdup_user(arg, sizeof(*sa));
4745 if (IS_ERR(sa)) {
4746 ret = PTR_ERR(sa);
4747 goto drop_write;
4748 }
4749
4750 trans = btrfs_join_transaction(root);
4751 if (IS_ERR(trans)) {
4752 ret = PTR_ERR(trans);
4753 goto out;
4754 }
4755
4756 qgroupid = sa->qgroupid;
4757 if (!qgroupid) {
4758 /* take the current subvol as qgroup */
4759 qgroupid = root->root_key.objectid;
4760 }
4761
4762 /* FIXME: check if the IDs really exist */
4763 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
4764
4765 err = btrfs_end_transaction(trans, root);
4766 if (err && !ret)
4767 ret = err;
4768
4769 out:
4770 kfree(sa);
4771 drop_write:
4772 mnt_drop_write_file(file);
4773 return ret;
4774 }
4775
4776 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4777 {
4778 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4779 struct btrfs_ioctl_quota_rescan_args *qsa;
4780 int ret;
4781
4782 if (!capable(CAP_SYS_ADMIN))
4783 return -EPERM;
4784
4785 ret = mnt_want_write_file(file);
4786 if (ret)
4787 return ret;
4788
4789 qsa = memdup_user(arg, sizeof(*qsa));
4790 if (IS_ERR(qsa)) {
4791 ret = PTR_ERR(qsa);
4792 goto drop_write;
4793 }
4794
4795 if (qsa->flags) {
4796 ret = -EINVAL;
4797 goto out;
4798 }
4799
4800 ret = btrfs_qgroup_rescan(root->fs_info);
4801
4802 out:
4803 kfree(qsa);
4804 drop_write:
4805 mnt_drop_write_file(file);
4806 return ret;
4807 }
4808
4809 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
4810 {
4811 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4812 struct btrfs_ioctl_quota_rescan_args *qsa;
4813 int ret = 0;
4814
4815 if (!capable(CAP_SYS_ADMIN))
4816 return -EPERM;
4817
4818 qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
4819 if (!qsa)
4820 return -ENOMEM;
4821
4822 if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4823 qsa->flags = 1;
4824 qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
4825 }
4826
4827 if (copy_to_user(arg, qsa, sizeof(*qsa)))
4828 ret = -EFAULT;
4829
4830 kfree(qsa);
4831 return ret;
4832 }
4833
4834 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
4835 {
4836 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4837
4838 if (!capable(CAP_SYS_ADMIN))
4839 return -EPERM;
4840
4841 return btrfs_qgroup_wait_for_completion(root->fs_info);
4842 }
4843
4844 static long _btrfs_ioctl_set_received_subvol(struct file *file,
4845 struct btrfs_ioctl_received_subvol_args *sa)
4846 {
4847 struct inode *inode = file_inode(file);
4848 struct btrfs_root *root = BTRFS_I(inode)->root;
4849 struct btrfs_root_item *root_item = &root->root_item;
4850 struct btrfs_trans_handle *trans;
4851 struct timespec ct = CURRENT_TIME;
4852 int ret = 0;
4853 int received_uuid_changed;
4854
4855 if (!inode_owner_or_capable(inode))
4856 return -EPERM;
4857
4858 ret = mnt_want_write_file(file);
4859 if (ret < 0)
4860 return ret;
4861
4862 down_write(&root->fs_info->subvol_sem);
4863
4864 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
4865 ret = -EINVAL;
4866 goto out;
4867 }
4868
4869 if (btrfs_root_readonly(root)) {
4870 ret = -EROFS;
4871 goto out;
4872 }
4873
4874 /*
4875 * 1 - root item
4876 * 2 - uuid items (received uuid + subvol uuid)
4877 */
4878 trans = btrfs_start_transaction(root, 3);
4879 if (IS_ERR(trans)) {
4880 ret = PTR_ERR(trans);
4881 trans = NULL;
4882 goto out;
4883 }
4884
4885 sa->rtransid = trans->transid;
4886 sa->rtime.sec = ct.tv_sec;
4887 sa->rtime.nsec = ct.tv_nsec;
4888
4889 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4890 BTRFS_UUID_SIZE);
4891 if (received_uuid_changed &&
4892 !btrfs_is_empty_uuid(root_item->received_uuid))
4893 btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
4894 root_item->received_uuid,
4895 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4896 root->root_key.objectid);
4897 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4898 btrfs_set_root_stransid(root_item, sa->stransid);
4899 btrfs_set_root_rtransid(root_item, sa->rtransid);
4900 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4901 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4902 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4903 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4904
4905 ret = btrfs_update_root(trans, root->fs_info->tree_root,
4906 &root->root_key, &root->root_item);
4907 if (ret < 0) {
4908 btrfs_end_transaction(trans, root);
4909 goto out;
4910 }
4911 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4912 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
4913 sa->uuid,
4914 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4915 root->root_key.objectid);
4916 if (ret < 0 && ret != -EEXIST) {
4917 btrfs_abort_transaction(trans, root, ret);
4918 goto out;
4919 }
4920 }
4921 ret = btrfs_commit_transaction(trans, root);
4922 if (ret < 0) {
4923 btrfs_abort_transaction(trans, root, ret);
4924 goto out;
4925 }
4926
4927 out:
4928 up_write(&root->fs_info->subvol_sem);
4929 mnt_drop_write_file(file);
4930 return ret;
4931 }
4932
4933 #ifdef CONFIG_64BIT
4934 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4935 void __user *arg)
4936 {
4937 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4938 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4939 int ret = 0;
4940
4941 args32 = memdup_user(arg, sizeof(*args32));
4942 if (IS_ERR(args32)) {
4943 ret = PTR_ERR(args32);
4944 args32 = NULL;
4945 goto out;
4946 }
4947
4948 args64 = kmalloc(sizeof(*args64), GFP_NOFS);
4949 if (!args64) {
4950 ret = -ENOMEM;
4951 goto out;
4952 }
4953
4954 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4955 args64->stransid = args32->stransid;
4956 args64->rtransid = args32->rtransid;
4957 args64->stime.sec = args32->stime.sec;
4958 args64->stime.nsec = args32->stime.nsec;
4959 args64->rtime.sec = args32->rtime.sec;
4960 args64->rtime.nsec = args32->rtime.nsec;
4961 args64->flags = args32->flags;
4962
4963 ret = _btrfs_ioctl_set_received_subvol(file, args64);
4964 if (ret)
4965 goto out;
4966
4967 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4968 args32->stransid = args64->stransid;
4969 args32->rtransid = args64->rtransid;
4970 args32->stime.sec = args64->stime.sec;
4971 args32->stime.nsec = args64->stime.nsec;
4972 args32->rtime.sec = args64->rtime.sec;
4973 args32->rtime.nsec = args64->rtime.nsec;
4974 args32->flags = args64->flags;
4975
4976 ret = copy_to_user(arg, args32, sizeof(*args32));
4977 if (ret)
4978 ret = -EFAULT;
4979
4980 out:
4981 kfree(args32);
4982 kfree(args64);
4983 return ret;
4984 }
4985 #endif
4986
4987 static long btrfs_ioctl_set_received_subvol(struct file *file,
4988 void __user *arg)
4989 {
4990 struct btrfs_ioctl_received_subvol_args *sa = NULL;
4991 int ret = 0;
4992
4993 sa = memdup_user(arg, sizeof(*sa));
4994 if (IS_ERR(sa)) {
4995 ret = PTR_ERR(sa);
4996 sa = NULL;
4997 goto out;
4998 }
4999
5000 ret = _btrfs_ioctl_set_received_subvol(file, sa);
5001
5002 if (ret)
5003 goto out;
5004
5005 ret = copy_to_user(arg, sa, sizeof(*sa));
5006 if (ret)
5007 ret = -EFAULT;
5008
5009 out:
5010 kfree(sa);
5011 return ret;
5012 }
5013
5014 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
5015 {
5016 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5017 size_t len;
5018 int ret;
5019 char label[BTRFS_LABEL_SIZE];
5020
5021 spin_lock(&root->fs_info->super_lock);
5022 memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5023 spin_unlock(&root->fs_info->super_lock);
5024
5025 len = strnlen(label, BTRFS_LABEL_SIZE);
5026
5027 if (len == BTRFS_LABEL_SIZE) {
5028 btrfs_warn(root->fs_info,
5029 "label is too long, return the first %zu bytes", --len);
5030 }
5031
5032 ret = copy_to_user(arg, label, len);
5033
5034 return ret ? -EFAULT : 0;
5035 }
5036
5037 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5038 {
5039 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5040 struct btrfs_super_block *super_block = root->fs_info->super_copy;
5041 struct btrfs_trans_handle *trans;
5042 char label[BTRFS_LABEL_SIZE];
5043 int ret;
5044
5045 if (!capable(CAP_SYS_ADMIN))
5046 return -EPERM;
5047
5048 if (copy_from_user(label, arg, sizeof(label)))
5049 return -EFAULT;
5050
5051 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5052 btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
5053 BTRFS_LABEL_SIZE - 1);
5054 return -EINVAL;
5055 }
5056
5057 ret = mnt_want_write_file(file);
5058 if (ret)
5059 return ret;
5060
5061 trans = btrfs_start_transaction(root, 0);
5062 if (IS_ERR(trans)) {
5063 ret = PTR_ERR(trans);
5064 goto out_unlock;
5065 }
5066
5067 spin_lock(&root->fs_info->super_lock);
5068 strcpy(super_block->label, label);
5069 spin_unlock(&root->fs_info->super_lock);
5070 ret = btrfs_commit_transaction(trans, root);
5071
5072 out_unlock:
5073 mnt_drop_write_file(file);
5074 return ret;
5075 }
5076
5077 #define INIT_FEATURE_FLAGS(suffix) \
5078 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5079 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5080 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5081
5082 static int btrfs_ioctl_get_supported_features(struct file *file,
5083 void __user *arg)
5084 {
5085 static struct btrfs_ioctl_feature_flags features[3] = {
5086 INIT_FEATURE_FLAGS(SUPP),
5087 INIT_FEATURE_FLAGS(SAFE_SET),
5088 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5089 };
5090
5091 if (copy_to_user(arg, &features, sizeof(features)))
5092 return -EFAULT;
5093
5094 return 0;
5095 }
5096
5097 static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5098 {
5099 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5100 struct btrfs_super_block *super_block = root->fs_info->super_copy;
5101 struct btrfs_ioctl_feature_flags features;
5102
5103 features.compat_flags = btrfs_super_compat_flags(super_block);
5104 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5105 features.incompat_flags = btrfs_super_incompat_flags(super_block);
5106
5107 if (copy_to_user(arg, &features, sizeof(features)))
5108 return -EFAULT;
5109
5110 return 0;
5111 }
5112
5113 static int check_feature_bits(struct btrfs_root *root,
5114 enum btrfs_feature_set set,
5115 u64 change_mask, u64 flags, u64 supported_flags,
5116 u64 safe_set, u64 safe_clear)
5117 {
5118 const char *type = btrfs_feature_set_names[set];
5119 char *names;
5120 u64 disallowed, unsupported;
5121 u64 set_mask = flags & change_mask;
5122 u64 clear_mask = ~flags & change_mask;
5123
5124 unsupported = set_mask & ~supported_flags;
5125 if (unsupported) {
5126 names = btrfs_printable_features(set, unsupported);
5127 if (names) {
5128 btrfs_warn(root->fs_info,
5129 "this kernel does not support the %s feature bit%s",
5130 names, strchr(names, ',') ? "s" : "");
5131 kfree(names);
5132 } else
5133 btrfs_warn(root->fs_info,
5134 "this kernel does not support %s bits 0x%llx",
5135 type, unsupported);
5136 return -EOPNOTSUPP;
5137 }
5138
5139 disallowed = set_mask & ~safe_set;
5140 if (disallowed) {
5141 names = btrfs_printable_features(set, disallowed);
5142 if (names) {
5143 btrfs_warn(root->fs_info,
5144 "can't set the %s feature bit%s while mounted",
5145 names, strchr(names, ',') ? "s" : "");
5146 kfree(names);
5147 } else
5148 btrfs_warn(root->fs_info,
5149 "can't set %s bits 0x%llx while mounted",
5150 type, disallowed);
5151 return -EPERM;
5152 }
5153
5154 disallowed = clear_mask & ~safe_clear;
5155 if (disallowed) {
5156 names = btrfs_printable_features(set, disallowed);
5157 if (names) {
5158 btrfs_warn(root->fs_info,
5159 "can't clear the %s feature bit%s while mounted",
5160 names, strchr(names, ',') ? "s" : "");
5161 kfree(names);
5162 } else
5163 btrfs_warn(root->fs_info,
5164 "can't clear %s bits 0x%llx while mounted",
5165 type, disallowed);
5166 return -EPERM;
5167 }
5168
5169 return 0;
5170 }
5171
5172 #define check_feature(root, change_mask, flags, mask_base) \
5173 check_feature_bits(root, FEAT_##mask_base, change_mask, flags, \
5174 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
5175 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
5176 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5177
5178 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5179 {
5180 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5181 struct btrfs_super_block *super_block = root->fs_info->super_copy;
5182 struct btrfs_ioctl_feature_flags flags[2];
5183 struct btrfs_trans_handle *trans;
5184 u64 newflags;
5185 int ret;
5186
5187 if (!capable(CAP_SYS_ADMIN))
5188 return -EPERM;
5189
5190 if (copy_from_user(flags, arg, sizeof(flags)))
5191 return -EFAULT;
5192
5193 /* Nothing to do */
5194 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5195 !flags[0].incompat_flags)
5196 return 0;
5197
5198 ret = check_feature(root, flags[0].compat_flags,
5199 flags[1].compat_flags, COMPAT);
5200 if (ret)
5201 return ret;
5202
5203 ret = check_feature(root, flags[0].compat_ro_flags,
5204 flags[1].compat_ro_flags, COMPAT_RO);
5205 if (ret)
5206 return ret;
5207
5208 ret = check_feature(root, flags[0].incompat_flags,
5209 flags[1].incompat_flags, INCOMPAT);
5210 if (ret)
5211 return ret;
5212
5213 trans = btrfs_start_transaction(root, 0);
5214 if (IS_ERR(trans))
5215 return PTR_ERR(trans);
5216
5217 spin_lock(&root->fs_info->super_lock);
5218 newflags = btrfs_super_compat_flags(super_block);
5219 newflags |= flags[0].compat_flags & flags[1].compat_flags;
5220 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5221 btrfs_set_super_compat_flags(super_block, newflags);
5222
5223 newflags = btrfs_super_compat_ro_flags(super_block);
5224 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5225 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5226 btrfs_set_super_compat_ro_flags(super_block, newflags);
5227
5228 newflags = btrfs_super_incompat_flags(super_block);
5229 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5230 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5231 btrfs_set_super_incompat_flags(super_block, newflags);
5232 spin_unlock(&root->fs_info->super_lock);
5233
5234 return btrfs_commit_transaction(trans, root);
5235 }
5236
5237 long btrfs_ioctl(struct file *file, unsigned int
5238 cmd, unsigned long arg)
5239 {
5240 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5241 void __user *argp = (void __user *)arg;
5242
5243 switch (cmd) {
5244 case FS_IOC_GETFLAGS:
5245 return btrfs_ioctl_getflags(file, argp);
5246 case FS_IOC_SETFLAGS:
5247 return btrfs_ioctl_setflags(file, argp);
5248 case FS_IOC_GETVERSION:
5249 return btrfs_ioctl_getversion(file, argp);
5250 case FITRIM:
5251 return btrfs_ioctl_fitrim(file, argp);
5252 case BTRFS_IOC_SNAP_CREATE:
5253 return btrfs_ioctl_snap_create(file, argp, 0);
5254 case BTRFS_IOC_SNAP_CREATE_V2:
5255 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5256 case BTRFS_IOC_SUBVOL_CREATE:
5257 return btrfs_ioctl_snap_create(file, argp, 1);
5258 case BTRFS_IOC_SUBVOL_CREATE_V2:
5259 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5260 case BTRFS_IOC_SNAP_DESTROY:
5261 return btrfs_ioctl_snap_destroy(file, argp);
5262 case BTRFS_IOC_SUBVOL_GETFLAGS:
5263 return btrfs_ioctl_subvol_getflags(file, argp);
5264 case BTRFS_IOC_SUBVOL_SETFLAGS:
5265 return btrfs_ioctl_subvol_setflags(file, argp);
5266 case BTRFS_IOC_DEFAULT_SUBVOL:
5267 return btrfs_ioctl_default_subvol(file, argp);
5268 case BTRFS_IOC_DEFRAG:
5269 return btrfs_ioctl_defrag(file, NULL);
5270 case BTRFS_IOC_DEFRAG_RANGE:
5271 return btrfs_ioctl_defrag(file, argp);
5272 case BTRFS_IOC_RESIZE:
5273 return btrfs_ioctl_resize(file, argp);
5274 case BTRFS_IOC_ADD_DEV:
5275 return btrfs_ioctl_add_dev(root, argp);
5276 case BTRFS_IOC_RM_DEV:
5277 return btrfs_ioctl_rm_dev(file, argp);
5278 case BTRFS_IOC_FS_INFO:
5279 return btrfs_ioctl_fs_info(root, argp);
5280 case BTRFS_IOC_DEV_INFO:
5281 return btrfs_ioctl_dev_info(root, argp);
5282 case BTRFS_IOC_BALANCE:
5283 return btrfs_ioctl_balance(file, NULL);
5284 case BTRFS_IOC_CLONE:
5285 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
5286 case BTRFS_IOC_CLONE_RANGE:
5287 return btrfs_ioctl_clone_range(file, argp);
5288 case BTRFS_IOC_TRANS_START:
5289 return btrfs_ioctl_trans_start(file);
5290 case BTRFS_IOC_TRANS_END:
5291 return btrfs_ioctl_trans_end(file);
5292 case BTRFS_IOC_TREE_SEARCH:
5293 return btrfs_ioctl_tree_search(file, argp);
5294 case BTRFS_IOC_TREE_SEARCH_V2:
5295 return btrfs_ioctl_tree_search_v2(file, argp);
5296 case BTRFS_IOC_INO_LOOKUP:
5297 return btrfs_ioctl_ino_lookup(file, argp);
5298 case BTRFS_IOC_INO_PATHS:
5299 return btrfs_ioctl_ino_to_path(root, argp);
5300 case BTRFS_IOC_LOGICAL_INO:
5301 return btrfs_ioctl_logical_to_ino(root, argp);
5302 case BTRFS_IOC_SPACE_INFO:
5303 return btrfs_ioctl_space_info(root, argp);
5304 case BTRFS_IOC_SYNC: {
5305 int ret;
5306
5307 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
5308 if (ret)
5309 return ret;
5310 ret = btrfs_sync_fs(file->f_dentry->d_sb, 1);
5311 return ret;
5312 }
5313 case BTRFS_IOC_START_SYNC:
5314 return btrfs_ioctl_start_sync(root, argp);
5315 case BTRFS_IOC_WAIT_SYNC:
5316 return btrfs_ioctl_wait_sync(root, argp);
5317 case BTRFS_IOC_SCRUB:
5318 return btrfs_ioctl_scrub(file, argp);
5319 case BTRFS_IOC_SCRUB_CANCEL:
5320 return btrfs_ioctl_scrub_cancel(root, argp);
5321 case BTRFS_IOC_SCRUB_PROGRESS:
5322 return btrfs_ioctl_scrub_progress(root, argp);
5323 case BTRFS_IOC_BALANCE_V2:
5324 return btrfs_ioctl_balance(file, argp);
5325 case BTRFS_IOC_BALANCE_CTL:
5326 return btrfs_ioctl_balance_ctl(root, arg);
5327 case BTRFS_IOC_BALANCE_PROGRESS:
5328 return btrfs_ioctl_balance_progress(root, argp);
5329 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5330 return btrfs_ioctl_set_received_subvol(file, argp);
5331 #ifdef CONFIG_64BIT
5332 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5333 return btrfs_ioctl_set_received_subvol_32(file, argp);
5334 #endif
5335 case BTRFS_IOC_SEND:
5336 return btrfs_ioctl_send(file, argp);
5337 case BTRFS_IOC_GET_DEV_STATS:
5338 return btrfs_ioctl_get_dev_stats(root, argp);
5339 case BTRFS_IOC_QUOTA_CTL:
5340 return btrfs_ioctl_quota_ctl(file, argp);
5341 case BTRFS_IOC_QGROUP_ASSIGN:
5342 return btrfs_ioctl_qgroup_assign(file, argp);
5343 case BTRFS_IOC_QGROUP_CREATE:
5344 return btrfs_ioctl_qgroup_create(file, argp);
5345 case BTRFS_IOC_QGROUP_LIMIT:
5346 return btrfs_ioctl_qgroup_limit(file, argp);
5347 case BTRFS_IOC_QUOTA_RESCAN:
5348 return btrfs_ioctl_quota_rescan(file, argp);
5349 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5350 return btrfs_ioctl_quota_rescan_status(file, argp);
5351 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5352 return btrfs_ioctl_quota_rescan_wait(file, argp);
5353 case BTRFS_IOC_DEV_REPLACE:
5354 return btrfs_ioctl_dev_replace(root, argp);
5355 case BTRFS_IOC_GET_FSLABEL:
5356 return btrfs_ioctl_get_fslabel(file, argp);
5357 case BTRFS_IOC_SET_FSLABEL:
5358 return btrfs_ioctl_set_fslabel(file, argp);
5359 case BTRFS_IOC_FILE_EXTENT_SAME:
5360 return btrfs_ioctl_file_extent_same(file, argp);
5361 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5362 return btrfs_ioctl_get_supported_features(file, argp);
5363 case BTRFS_IOC_GET_FEATURES:
5364 return btrfs_ioctl_get_features(file, argp);
5365 case BTRFS_IOC_SET_FEATURES:
5366 return btrfs_ioctl_set_features(file, argp);
5367 }
5368
5369 return -ENOTTY;
5370 }
Linux kernel - Deliverables
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