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Merge tag 'imx-fixes-3.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/shawngu...
[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 unsigned int new_fl = 0;
140
141 if (ip->flags & BTRFS_INODE_SYNC)
142 new_fl |= S_SYNC;
143 if (ip->flags & BTRFS_INODE_IMMUTABLE)
144 new_fl |= S_IMMUTABLE;
145 if (ip->flags & BTRFS_INODE_APPEND)
146 new_fl |= S_APPEND;
147 if (ip->flags & BTRFS_INODE_NOATIME)
148 new_fl |= S_NOATIME;
149 if (ip->flags & BTRFS_INODE_DIRSYNC)
150 new_fl |= S_DIRSYNC;
151
152 set_mask_bits(&inode->i_flags,
153 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
154 new_fl);
155 }
156
157 /*
158 * Inherit flags from the parent inode.
159 *
160 * Currently only the compression flags and the cow flags are inherited.
161 */
162 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
163 {
164 unsigned int flags;
165
166 if (!dir)
167 return;
168
169 flags = BTRFS_I(dir)->flags;
170
171 if (flags & BTRFS_INODE_NOCOMPRESS) {
172 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
173 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
174 } else if (flags & BTRFS_INODE_COMPRESS) {
175 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
176 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
177 }
178
179 if (flags & BTRFS_INODE_NODATACOW) {
180 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
181 if (S_ISREG(inode->i_mode))
182 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
183 }
184
185 btrfs_update_iflags(inode);
186 }
187
188 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
189 {
190 struct btrfs_inode *ip = BTRFS_I(file_inode(file));
191 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
192
193 if (copy_to_user(arg, &flags, sizeof(flags)))
194 return -EFAULT;
195 return 0;
196 }
197
198 static int check_flags(unsigned int flags)
199 {
200 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
201 FS_NOATIME_FL | FS_NODUMP_FL | \
202 FS_SYNC_FL | FS_DIRSYNC_FL | \
203 FS_NOCOMP_FL | FS_COMPR_FL |
204 FS_NOCOW_FL))
205 return -EOPNOTSUPP;
206
207 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
208 return -EINVAL;
209
210 return 0;
211 }
212
213 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
214 {
215 struct inode *inode = file_inode(file);
216 struct btrfs_inode *ip = BTRFS_I(inode);
217 struct btrfs_root *root = ip->root;
218 struct btrfs_trans_handle *trans;
219 unsigned int flags, oldflags;
220 int ret;
221 u64 ip_oldflags;
222 unsigned int i_oldflags;
223 umode_t mode;
224
225 if (!inode_owner_or_capable(inode))
226 return -EPERM;
227
228 if (btrfs_root_readonly(root))
229 return -EROFS;
230
231 if (copy_from_user(&flags, arg, sizeof(flags)))
232 return -EFAULT;
233
234 ret = check_flags(flags);
235 if (ret)
236 return ret;
237
238 ret = mnt_want_write_file(file);
239 if (ret)
240 return ret;
241
242 mutex_lock(&inode->i_mutex);
243
244 ip_oldflags = ip->flags;
245 i_oldflags = inode->i_flags;
246 mode = inode->i_mode;
247
248 flags = btrfs_mask_flags(inode->i_mode, flags);
249 oldflags = btrfs_flags_to_ioctl(ip->flags);
250 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
251 if (!capable(CAP_LINUX_IMMUTABLE)) {
252 ret = -EPERM;
253 goto out_unlock;
254 }
255 }
256
257 if (flags & FS_SYNC_FL)
258 ip->flags |= BTRFS_INODE_SYNC;
259 else
260 ip->flags &= ~BTRFS_INODE_SYNC;
261 if (flags & FS_IMMUTABLE_FL)
262 ip->flags |= BTRFS_INODE_IMMUTABLE;
263 else
264 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
265 if (flags & FS_APPEND_FL)
266 ip->flags |= BTRFS_INODE_APPEND;
267 else
268 ip->flags &= ~BTRFS_INODE_APPEND;
269 if (flags & FS_NODUMP_FL)
270 ip->flags |= BTRFS_INODE_NODUMP;
271 else
272 ip->flags &= ~BTRFS_INODE_NODUMP;
273 if (flags & FS_NOATIME_FL)
274 ip->flags |= BTRFS_INODE_NOATIME;
275 else
276 ip->flags &= ~BTRFS_INODE_NOATIME;
277 if (flags & FS_DIRSYNC_FL)
278 ip->flags |= BTRFS_INODE_DIRSYNC;
279 else
280 ip->flags &= ~BTRFS_INODE_DIRSYNC;
281 if (flags & FS_NOCOW_FL) {
282 if (S_ISREG(mode)) {
283 /*
284 * It's safe to turn csums off here, no extents exist.
285 * Otherwise we want the flag to reflect the real COW
286 * status of the file and will not set it.
287 */
288 if (inode->i_size == 0)
289 ip->flags |= BTRFS_INODE_NODATACOW
290 | BTRFS_INODE_NODATASUM;
291 } else {
292 ip->flags |= BTRFS_INODE_NODATACOW;
293 }
294 } else {
295 /*
296 * Revert back under same assuptions as above
297 */
298 if (S_ISREG(mode)) {
299 if (inode->i_size == 0)
300 ip->flags &= ~(BTRFS_INODE_NODATACOW
301 | BTRFS_INODE_NODATASUM);
302 } else {
303 ip->flags &= ~BTRFS_INODE_NODATACOW;
304 }
305 }
306
307 /*
308 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
309 * flag may be changed automatically if compression code won't make
310 * things smaller.
311 */
312 if (flags & FS_NOCOMP_FL) {
313 ip->flags &= ~BTRFS_INODE_COMPRESS;
314 ip->flags |= BTRFS_INODE_NOCOMPRESS;
315
316 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
317 if (ret && ret != -ENODATA)
318 goto out_drop;
319 } else if (flags & FS_COMPR_FL) {
320 const char *comp;
321
322 ip->flags |= BTRFS_INODE_COMPRESS;
323 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
324
325 if (root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
326 comp = "lzo";
327 else
328 comp = "zlib";
329 ret = btrfs_set_prop(inode, "btrfs.compression",
330 comp, strlen(comp), 0);
331 if (ret)
332 goto out_drop;
333
334 } else {
335 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
336 }
337
338 trans = btrfs_start_transaction(root, 1);
339 if (IS_ERR(trans)) {
340 ret = PTR_ERR(trans);
341 goto out_drop;
342 }
343
344 btrfs_update_iflags(inode);
345 inode_inc_iversion(inode);
346 inode->i_ctime = CURRENT_TIME;
347 ret = btrfs_update_inode(trans, root, inode);
348
349 btrfs_end_transaction(trans, root);
350 out_drop:
351 if (ret) {
352 ip->flags = ip_oldflags;
353 inode->i_flags = i_oldflags;
354 }
355
356 out_unlock:
357 mutex_unlock(&inode->i_mutex);
358 mnt_drop_write_file(file);
359 return ret;
360 }
361
362 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
363 {
364 struct inode *inode = file_inode(file);
365
366 return put_user(inode->i_generation, arg);
367 }
368
369 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
370 {
371 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
372 struct btrfs_device *device;
373 struct request_queue *q;
374 struct fstrim_range range;
375 u64 minlen = ULLONG_MAX;
376 u64 num_devices = 0;
377 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
378 int ret;
379
380 if (!capable(CAP_SYS_ADMIN))
381 return -EPERM;
382
383 rcu_read_lock();
384 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
385 dev_list) {
386 if (!device->bdev)
387 continue;
388 q = bdev_get_queue(device->bdev);
389 if (blk_queue_discard(q)) {
390 num_devices++;
391 minlen = min((u64)q->limits.discard_granularity,
392 minlen);
393 }
394 }
395 rcu_read_unlock();
396
397 if (!num_devices)
398 return -EOPNOTSUPP;
399 if (copy_from_user(&range, arg, sizeof(range)))
400 return -EFAULT;
401 if (range.start > total_bytes ||
402 range.len < fs_info->sb->s_blocksize)
403 return -EINVAL;
404
405 range.len = min(range.len, total_bytes - range.start);
406 range.minlen = max(range.minlen, minlen);
407 ret = btrfs_trim_fs(fs_info->tree_root, &range);
408 if (ret < 0)
409 return ret;
410
411 if (copy_to_user(arg, &range, sizeof(range)))
412 return -EFAULT;
413
414 return 0;
415 }
416
417 int btrfs_is_empty_uuid(u8 *uuid)
418 {
419 int i;
420
421 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
422 if (uuid[i])
423 return 0;
424 }
425 return 1;
426 }
427
428 static noinline int create_subvol(struct inode *dir,
429 struct dentry *dentry,
430 char *name, int namelen,
431 u64 *async_transid,
432 struct btrfs_qgroup_inherit *inherit)
433 {
434 struct btrfs_trans_handle *trans;
435 struct btrfs_key key;
436 struct btrfs_root_item root_item;
437 struct btrfs_inode_item *inode_item;
438 struct extent_buffer *leaf;
439 struct btrfs_root *root = BTRFS_I(dir)->root;
440 struct btrfs_root *new_root;
441 struct btrfs_block_rsv block_rsv;
442 struct timespec cur_time = CURRENT_TIME;
443 struct inode *inode;
444 int ret;
445 int err;
446 u64 objectid;
447 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
448 u64 index = 0;
449 u64 qgroup_reserved;
450 uuid_le new_uuid;
451
452 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
453 if (ret)
454 return ret;
455
456 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
457 /*
458 * The same as the snapshot creation, please see the comment
459 * of create_snapshot().
460 */
461 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
462 8, &qgroup_reserved, false);
463 if (ret)
464 return ret;
465
466 trans = btrfs_start_transaction(root, 0);
467 if (IS_ERR(trans)) {
468 ret = PTR_ERR(trans);
469 btrfs_subvolume_release_metadata(root, &block_rsv,
470 qgroup_reserved);
471 return ret;
472 }
473 trans->block_rsv = &block_rsv;
474 trans->bytes_reserved = block_rsv.size;
475
476 ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
477 if (ret)
478 goto fail;
479
480 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
481 0, objectid, NULL, 0, 0, 0);
482 if (IS_ERR(leaf)) {
483 ret = PTR_ERR(leaf);
484 goto fail;
485 }
486
487 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
488 btrfs_set_header_bytenr(leaf, leaf->start);
489 btrfs_set_header_generation(leaf, trans->transid);
490 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
491 btrfs_set_header_owner(leaf, objectid);
492
493 write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(),
494 BTRFS_FSID_SIZE);
495 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
496 btrfs_header_chunk_tree_uuid(leaf),
497 BTRFS_UUID_SIZE);
498 btrfs_mark_buffer_dirty(leaf);
499
500 memset(&root_item, 0, sizeof(root_item));
501
502 inode_item = &root_item.inode;
503 btrfs_set_stack_inode_generation(inode_item, 1);
504 btrfs_set_stack_inode_size(inode_item, 3);
505 btrfs_set_stack_inode_nlink(inode_item, 1);
506 btrfs_set_stack_inode_nbytes(inode_item, root->leafsize);
507 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
508
509 btrfs_set_root_flags(&root_item, 0);
510 btrfs_set_root_limit(&root_item, 0);
511 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
512
513 btrfs_set_root_bytenr(&root_item, leaf->start);
514 btrfs_set_root_generation(&root_item, trans->transid);
515 btrfs_set_root_level(&root_item, 0);
516 btrfs_set_root_refs(&root_item, 1);
517 btrfs_set_root_used(&root_item, leaf->len);
518 btrfs_set_root_last_snapshot(&root_item, 0);
519
520 btrfs_set_root_generation_v2(&root_item,
521 btrfs_root_generation(&root_item));
522 uuid_le_gen(&new_uuid);
523 memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
524 btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
525 btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec);
526 root_item.ctime = root_item.otime;
527 btrfs_set_root_ctransid(&root_item, trans->transid);
528 btrfs_set_root_otransid(&root_item, trans->transid);
529
530 btrfs_tree_unlock(leaf);
531 free_extent_buffer(leaf);
532 leaf = NULL;
533
534 btrfs_set_root_dirid(&root_item, new_dirid);
535
536 key.objectid = objectid;
537 key.offset = 0;
538 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
539 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
540 &root_item);
541 if (ret)
542 goto fail;
543
544 key.offset = (u64)-1;
545 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
546 if (IS_ERR(new_root)) {
547 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
548 ret = PTR_ERR(new_root);
549 goto fail;
550 }
551
552 btrfs_record_root_in_trans(trans, new_root);
553
554 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
555 if (ret) {
556 /* We potentially lose an unused inode item here */
557 btrfs_abort_transaction(trans, root, ret);
558 goto fail;
559 }
560
561 /*
562 * insert the directory item
563 */
564 ret = btrfs_set_inode_index(dir, &index);
565 if (ret) {
566 btrfs_abort_transaction(trans, root, ret);
567 goto fail;
568 }
569
570 ret = btrfs_insert_dir_item(trans, root,
571 name, namelen, dir, &key,
572 BTRFS_FT_DIR, index);
573 if (ret) {
574 btrfs_abort_transaction(trans, root, ret);
575 goto fail;
576 }
577
578 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
579 ret = btrfs_update_inode(trans, root, dir);
580 BUG_ON(ret);
581
582 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
583 objectid, root->root_key.objectid,
584 btrfs_ino(dir), index, name, namelen);
585 BUG_ON(ret);
586
587 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
588 root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
589 objectid);
590 if (ret)
591 btrfs_abort_transaction(trans, root, ret);
592
593 fail:
594 trans->block_rsv = NULL;
595 trans->bytes_reserved = 0;
596 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
597
598 if (async_transid) {
599 *async_transid = trans->transid;
600 err = btrfs_commit_transaction_async(trans, root, 1);
601 if (err)
602 err = btrfs_commit_transaction(trans, root);
603 } else {
604 err = btrfs_commit_transaction(trans, root);
605 }
606 if (err && !ret)
607 ret = err;
608
609 if (!ret) {
610 inode = btrfs_lookup_dentry(dir, dentry);
611 if (IS_ERR(inode))
612 return PTR_ERR(inode);
613 d_instantiate(dentry, inode);
614 }
615 return ret;
616 }
617
618 static void btrfs_wait_nocow_write(struct btrfs_root *root)
619 {
620 s64 writers;
621 DEFINE_WAIT(wait);
622
623 do {
624 prepare_to_wait(&root->subv_writers->wait, &wait,
625 TASK_UNINTERRUPTIBLE);
626
627 writers = percpu_counter_sum(&root->subv_writers->counter);
628 if (writers)
629 schedule();
630
631 finish_wait(&root->subv_writers->wait, &wait);
632 } while (writers);
633 }
634
635 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
636 struct dentry *dentry, char *name, int namelen,
637 u64 *async_transid, bool readonly,
638 struct btrfs_qgroup_inherit *inherit)
639 {
640 struct inode *inode;
641 struct btrfs_pending_snapshot *pending_snapshot;
642 struct btrfs_trans_handle *trans;
643 int ret;
644
645 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
646 return -EINVAL;
647
648 atomic_inc(&root->will_be_snapshoted);
649 smp_mb__after_atomic();
650 btrfs_wait_nocow_write(root);
651
652 ret = btrfs_start_delalloc_inodes(root, 0);
653 if (ret)
654 goto out;
655
656 btrfs_wait_ordered_extents(root, -1);
657
658 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
659 if (!pending_snapshot) {
660 ret = -ENOMEM;
661 goto out;
662 }
663
664 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
665 BTRFS_BLOCK_RSV_TEMP);
666 /*
667 * 1 - parent dir inode
668 * 2 - dir entries
669 * 1 - root item
670 * 2 - root ref/backref
671 * 1 - root of snapshot
672 * 1 - UUID item
673 */
674 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
675 &pending_snapshot->block_rsv, 8,
676 &pending_snapshot->qgroup_reserved,
677 false);
678 if (ret)
679 goto free;
680
681 pending_snapshot->dentry = dentry;
682 pending_snapshot->root = root;
683 pending_snapshot->readonly = readonly;
684 pending_snapshot->dir = dir;
685 pending_snapshot->inherit = inherit;
686
687 trans = btrfs_start_transaction(root, 0);
688 if (IS_ERR(trans)) {
689 ret = PTR_ERR(trans);
690 goto fail;
691 }
692
693 spin_lock(&root->fs_info->trans_lock);
694 list_add(&pending_snapshot->list,
695 &trans->transaction->pending_snapshots);
696 spin_unlock(&root->fs_info->trans_lock);
697 if (async_transid) {
698 *async_transid = trans->transid;
699 ret = btrfs_commit_transaction_async(trans,
700 root->fs_info->extent_root, 1);
701 if (ret)
702 ret = btrfs_commit_transaction(trans, root);
703 } else {
704 ret = btrfs_commit_transaction(trans,
705 root->fs_info->extent_root);
706 }
707 if (ret)
708 goto fail;
709
710 ret = pending_snapshot->error;
711 if (ret)
712 goto fail;
713
714 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
715 if (ret)
716 goto fail;
717
718 /*
719 * If orphan cleanup did remove any orphans, it means the tree was
720 * modified and therefore the commit root is not the same as the
721 * current root anymore. This is a problem, because send uses the
722 * commit root and therefore can see inode items that don't exist
723 * in the current root anymore, and for example make calls to
724 * btrfs_iget, which will do tree lookups based on the current root
725 * and not on the commit root. Those lookups will fail, returning a
726 * -ESTALE error, and making send fail with that error. So make sure
727 * a send does not see any orphans we have just removed, and that it
728 * will see the same inodes regardless of whether a transaction
729 * commit happened before it started (meaning that the commit root
730 * will be the same as the current root) or not.
731 */
732 if (readonly && pending_snapshot->snap->node !=
733 pending_snapshot->snap->commit_root) {
734 trans = btrfs_join_transaction(pending_snapshot->snap);
735 if (IS_ERR(trans) && PTR_ERR(trans) != -ENOENT) {
736 ret = PTR_ERR(trans);
737 goto fail;
738 }
739 if (!IS_ERR(trans)) {
740 ret = btrfs_commit_transaction(trans,
741 pending_snapshot->snap);
742 if (ret)
743 goto fail;
744 }
745 }
746
747 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
748 if (IS_ERR(inode)) {
749 ret = PTR_ERR(inode);
750 goto fail;
751 }
752
753 d_instantiate(dentry, inode);
754 ret = 0;
755 fail:
756 btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
757 &pending_snapshot->block_rsv,
758 pending_snapshot->qgroup_reserved);
759 free:
760 kfree(pending_snapshot);
761 out:
762 atomic_dec(&root->will_be_snapshoted);
763 return ret;
764 }
765
766 /* copy of check_sticky in fs/namei.c()
767 * It's inline, so penalty for filesystems that don't use sticky bit is
768 * minimal.
769 */
770 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
771 {
772 kuid_t fsuid = current_fsuid();
773
774 if (!(dir->i_mode & S_ISVTX))
775 return 0;
776 if (uid_eq(inode->i_uid, fsuid))
777 return 0;
778 if (uid_eq(dir->i_uid, fsuid))
779 return 0;
780 return !capable(CAP_FOWNER);
781 }
782
783 /* copy of may_delete in fs/namei.c()
784 * Check whether we can remove a link victim from directory dir, check
785 * whether the type of victim is right.
786 * 1. We can't do it if dir is read-only (done in permission())
787 * 2. We should have write and exec permissions on dir
788 * 3. We can't remove anything from append-only dir
789 * 4. We can't do anything with immutable dir (done in permission())
790 * 5. If the sticky bit on dir is set we should either
791 * a. be owner of dir, or
792 * b. be owner of victim, or
793 * c. have CAP_FOWNER capability
794 * 6. If the victim is append-only or immutable we can't do antyhing with
795 * links pointing to it.
796 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
797 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
798 * 9. We can't remove a root or mountpoint.
799 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
800 * nfs_async_unlink().
801 */
802
803 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
804 {
805 int error;
806
807 if (!victim->d_inode)
808 return -ENOENT;
809
810 BUG_ON(victim->d_parent->d_inode != dir);
811 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
812
813 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
814 if (error)
815 return error;
816 if (IS_APPEND(dir))
817 return -EPERM;
818 if (btrfs_check_sticky(dir, victim->d_inode)||
819 IS_APPEND(victim->d_inode)||
820 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
821 return -EPERM;
822 if (isdir) {
823 if (!S_ISDIR(victim->d_inode->i_mode))
824 return -ENOTDIR;
825 if (IS_ROOT(victim))
826 return -EBUSY;
827 } else if (S_ISDIR(victim->d_inode->i_mode))
828 return -EISDIR;
829 if (IS_DEADDIR(dir))
830 return -ENOENT;
831 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
832 return -EBUSY;
833 return 0;
834 }
835
836 /* copy of may_create in fs/namei.c() */
837 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
838 {
839 if (child->d_inode)
840 return -EEXIST;
841 if (IS_DEADDIR(dir))
842 return -ENOENT;
843 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
844 }
845
846 /*
847 * Create a new subvolume below @parent. This is largely modeled after
848 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
849 * inside this filesystem so it's quite a bit simpler.
850 */
851 static noinline int btrfs_mksubvol(struct path *parent,
852 char *name, int namelen,
853 struct btrfs_root *snap_src,
854 u64 *async_transid, bool readonly,
855 struct btrfs_qgroup_inherit *inherit)
856 {
857 struct inode *dir = parent->dentry->d_inode;
858 struct dentry *dentry;
859 int error;
860
861 error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
862 if (error == -EINTR)
863 return error;
864
865 dentry = lookup_one_len(name, parent->dentry, namelen);
866 error = PTR_ERR(dentry);
867 if (IS_ERR(dentry))
868 goto out_unlock;
869
870 error = -EEXIST;
871 if (dentry->d_inode)
872 goto out_dput;
873
874 error = btrfs_may_create(dir, dentry);
875 if (error)
876 goto out_dput;
877
878 /*
879 * even if this name doesn't exist, we may get hash collisions.
880 * check for them now when we can safely fail
881 */
882 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
883 dir->i_ino, name,
884 namelen);
885 if (error)
886 goto out_dput;
887
888 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
889
890 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
891 goto out_up_read;
892
893 if (snap_src) {
894 error = create_snapshot(snap_src, dir, dentry, name, namelen,
895 async_transid, readonly, inherit);
896 } else {
897 error = create_subvol(dir, dentry, name, namelen,
898 async_transid, inherit);
899 }
900 if (!error)
901 fsnotify_mkdir(dir, dentry);
902 out_up_read:
903 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
904 out_dput:
905 dput(dentry);
906 out_unlock:
907 mutex_unlock(&dir->i_mutex);
908 return error;
909 }
910
911 /*
912 * When we're defragging a range, we don't want to kick it off again
913 * if it is really just waiting for delalloc to send it down.
914 * If we find a nice big extent or delalloc range for the bytes in the
915 * file you want to defrag, we return 0 to let you know to skip this
916 * part of the file
917 */
918 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
919 {
920 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
921 struct extent_map *em = NULL;
922 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
923 u64 end;
924
925 read_lock(&em_tree->lock);
926 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
927 read_unlock(&em_tree->lock);
928
929 if (em) {
930 end = extent_map_end(em);
931 free_extent_map(em);
932 if (end - offset > thresh)
933 return 0;
934 }
935 /* if we already have a nice delalloc here, just stop */
936 thresh /= 2;
937 end = count_range_bits(io_tree, &offset, offset + thresh,
938 thresh, EXTENT_DELALLOC, 1);
939 if (end >= thresh)
940 return 0;
941 return 1;
942 }
943
944 /*
945 * helper function to walk through a file and find extents
946 * newer than a specific transid, and smaller than thresh.
947 *
948 * This is used by the defragging code to find new and small
949 * extents
950 */
951 static int find_new_extents(struct btrfs_root *root,
952 struct inode *inode, u64 newer_than,
953 u64 *off, int thresh)
954 {
955 struct btrfs_path *path;
956 struct btrfs_key min_key;
957 struct extent_buffer *leaf;
958 struct btrfs_file_extent_item *extent;
959 int type;
960 int ret;
961 u64 ino = btrfs_ino(inode);
962
963 path = btrfs_alloc_path();
964 if (!path)
965 return -ENOMEM;
966
967 min_key.objectid = ino;
968 min_key.type = BTRFS_EXTENT_DATA_KEY;
969 min_key.offset = *off;
970
971 while (1) {
972 path->keep_locks = 1;
973 ret = btrfs_search_forward(root, &min_key, path, newer_than);
974 if (ret != 0)
975 goto none;
976 path->keep_locks = 0;
977 btrfs_unlock_up_safe(path, 1);
978 process_slot:
979 if (min_key.objectid != ino)
980 goto none;
981 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
982 goto none;
983
984 leaf = path->nodes[0];
985 extent = btrfs_item_ptr(leaf, path->slots[0],
986 struct btrfs_file_extent_item);
987
988 type = btrfs_file_extent_type(leaf, extent);
989 if (type == BTRFS_FILE_EXTENT_REG &&
990 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
991 check_defrag_in_cache(inode, min_key.offset, thresh)) {
992 *off = min_key.offset;
993 btrfs_free_path(path);
994 return 0;
995 }
996
997 path->slots[0]++;
998 if (path->slots[0] < btrfs_header_nritems(leaf)) {
999 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
1000 goto process_slot;
1001 }
1002
1003 if (min_key.offset == (u64)-1)
1004 goto none;
1005
1006 min_key.offset++;
1007 btrfs_release_path(path);
1008 }
1009 none:
1010 btrfs_free_path(path);
1011 return -ENOENT;
1012 }
1013
1014 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
1015 {
1016 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1017 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1018 struct extent_map *em;
1019 u64 len = PAGE_CACHE_SIZE;
1020
1021 /*
1022 * hopefully we have this extent in the tree already, try without
1023 * the full extent lock
1024 */
1025 read_lock(&em_tree->lock);
1026 em = lookup_extent_mapping(em_tree, start, len);
1027 read_unlock(&em_tree->lock);
1028
1029 if (!em) {
1030 struct extent_state *cached = NULL;
1031 u64 end = start + len - 1;
1032
1033 /* get the big lock and read metadata off disk */
1034 lock_extent_bits(io_tree, start, end, 0, &cached);
1035 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
1036 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
1037
1038 if (IS_ERR(em))
1039 return NULL;
1040 }
1041
1042 return em;
1043 }
1044
1045 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1046 {
1047 struct extent_map *next;
1048 bool ret = true;
1049
1050 /* this is the last extent */
1051 if (em->start + em->len >= i_size_read(inode))
1052 return false;
1053
1054 next = defrag_lookup_extent(inode, em->start + em->len);
1055 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE ||
1056 (em->block_start + em->block_len == next->block_start))
1057 ret = false;
1058
1059 free_extent_map(next);
1060 return ret;
1061 }
1062
1063 static int should_defrag_range(struct inode *inode, u64 start, int thresh,
1064 u64 *last_len, u64 *skip, u64 *defrag_end,
1065 int compress)
1066 {
1067 struct extent_map *em;
1068 int ret = 1;
1069 bool next_mergeable = true;
1070
1071 /*
1072 * make sure that once we start defragging an extent, we keep on
1073 * defragging it
1074 */
1075 if (start < *defrag_end)
1076 return 1;
1077
1078 *skip = 0;
1079
1080 em = defrag_lookup_extent(inode, start);
1081 if (!em)
1082 return 0;
1083
1084 /* this will cover holes, and inline extents */
1085 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1086 ret = 0;
1087 goto out;
1088 }
1089
1090 next_mergeable = defrag_check_next_extent(inode, em);
1091
1092 /*
1093 * we hit a real extent, if it is big or the next extent is not a
1094 * real extent, don't bother defragging it
1095 */
1096 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1097 (em->len >= thresh || !next_mergeable))
1098 ret = 0;
1099 out:
1100 /*
1101 * last_len ends up being a counter of how many bytes we've defragged.
1102 * every time we choose not to defrag an extent, we reset *last_len
1103 * so that the next tiny extent will force a defrag.
1104 *
1105 * The end result of this is that tiny extents before a single big
1106 * extent will force at least part of that big extent to be defragged.
1107 */
1108 if (ret) {
1109 *defrag_end = extent_map_end(em);
1110 } else {
1111 *last_len = 0;
1112 *skip = extent_map_end(em);
1113 *defrag_end = 0;
1114 }
1115
1116 free_extent_map(em);
1117 return ret;
1118 }
1119
1120 /*
1121 * it doesn't do much good to defrag one or two pages
1122 * at a time. This pulls in a nice chunk of pages
1123 * to COW and defrag.
1124 *
1125 * It also makes sure the delalloc code has enough
1126 * dirty data to avoid making new small extents as part
1127 * of the defrag
1128 *
1129 * It's a good idea to start RA on this range
1130 * before calling this.
1131 */
1132 static int cluster_pages_for_defrag(struct inode *inode,
1133 struct page **pages,
1134 unsigned long start_index,
1135 unsigned long num_pages)
1136 {
1137 unsigned long file_end;
1138 u64 isize = i_size_read(inode);
1139 u64 page_start;
1140 u64 page_end;
1141 u64 page_cnt;
1142 int ret;
1143 int i;
1144 int i_done;
1145 struct btrfs_ordered_extent *ordered;
1146 struct extent_state *cached_state = NULL;
1147 struct extent_io_tree *tree;
1148 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1149
1150 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1151 if (!isize || start_index > file_end)
1152 return 0;
1153
1154 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1155
1156 ret = btrfs_delalloc_reserve_space(inode,
1157 page_cnt << PAGE_CACHE_SHIFT);
1158 if (ret)
1159 return ret;
1160 i_done = 0;
1161 tree = &BTRFS_I(inode)->io_tree;
1162
1163 /* step one, lock all the pages */
1164 for (i = 0; i < page_cnt; i++) {
1165 struct page *page;
1166 again:
1167 page = find_or_create_page(inode->i_mapping,
1168 start_index + i, mask);
1169 if (!page)
1170 break;
1171
1172 page_start = page_offset(page);
1173 page_end = page_start + PAGE_CACHE_SIZE - 1;
1174 while (1) {
1175 lock_extent_bits(tree, page_start, page_end,
1176 0, &cached_state);
1177 ordered = btrfs_lookup_ordered_extent(inode,
1178 page_start);
1179 unlock_extent_cached(tree, page_start, page_end,
1180 &cached_state, GFP_NOFS);
1181 if (!ordered)
1182 break;
1183
1184 unlock_page(page);
1185 btrfs_start_ordered_extent(inode, ordered, 1);
1186 btrfs_put_ordered_extent(ordered);
1187 lock_page(page);
1188 /*
1189 * we unlocked the page above, so we need check if
1190 * it was released or not.
1191 */
1192 if (page->mapping != inode->i_mapping) {
1193 unlock_page(page);
1194 page_cache_release(page);
1195 goto again;
1196 }
1197 }
1198
1199 if (!PageUptodate(page)) {
1200 btrfs_readpage(NULL, page);
1201 lock_page(page);
1202 if (!PageUptodate(page)) {
1203 unlock_page(page);
1204 page_cache_release(page);
1205 ret = -EIO;
1206 break;
1207 }
1208 }
1209
1210 if (page->mapping != inode->i_mapping) {
1211 unlock_page(page);
1212 page_cache_release(page);
1213 goto again;
1214 }
1215
1216 pages[i] = page;
1217 i_done++;
1218 }
1219 if (!i_done || ret)
1220 goto out;
1221
1222 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1223 goto out;
1224
1225 /*
1226 * so now we have a nice long stream of locked
1227 * and up to date pages, lets wait on them
1228 */
1229 for (i = 0; i < i_done; i++)
1230 wait_on_page_writeback(pages[i]);
1231
1232 page_start = page_offset(pages[0]);
1233 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1234
1235 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1236 page_start, page_end - 1, 0, &cached_state);
1237 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1238 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1239 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1240 &cached_state, GFP_NOFS);
1241
1242 if (i_done != page_cnt) {
1243 spin_lock(&BTRFS_I(inode)->lock);
1244 BTRFS_I(inode)->outstanding_extents++;
1245 spin_unlock(&BTRFS_I(inode)->lock);
1246 btrfs_delalloc_release_space(inode,
1247 (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1248 }
1249
1250
1251 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1252 &cached_state, GFP_NOFS);
1253
1254 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1255 page_start, page_end - 1, &cached_state,
1256 GFP_NOFS);
1257
1258 for (i = 0; i < i_done; i++) {
1259 clear_page_dirty_for_io(pages[i]);
1260 ClearPageChecked(pages[i]);
1261 set_page_extent_mapped(pages[i]);
1262 set_page_dirty(pages[i]);
1263 unlock_page(pages[i]);
1264 page_cache_release(pages[i]);
1265 }
1266 return i_done;
1267 out:
1268 for (i = 0; i < i_done; i++) {
1269 unlock_page(pages[i]);
1270 page_cache_release(pages[i]);
1271 }
1272 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1273 return ret;
1274
1275 }
1276
1277 int btrfs_defrag_file(struct inode *inode, struct file *file,
1278 struct btrfs_ioctl_defrag_range_args *range,
1279 u64 newer_than, unsigned long max_to_defrag)
1280 {
1281 struct btrfs_root *root = BTRFS_I(inode)->root;
1282 struct file_ra_state *ra = NULL;
1283 unsigned long last_index;
1284 u64 isize = i_size_read(inode);
1285 u64 last_len = 0;
1286 u64 skip = 0;
1287 u64 defrag_end = 0;
1288 u64 newer_off = range->start;
1289 unsigned long i;
1290 unsigned long ra_index = 0;
1291 int ret;
1292 int defrag_count = 0;
1293 int compress_type = BTRFS_COMPRESS_ZLIB;
1294 int extent_thresh = range->extent_thresh;
1295 unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1296 unsigned long cluster = max_cluster;
1297 u64 new_align = ~((u64)128 * 1024 - 1);
1298 struct page **pages = NULL;
1299
1300 if (isize == 0)
1301 return 0;
1302
1303 if (range->start >= isize)
1304 return -EINVAL;
1305
1306 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1307 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1308 return -EINVAL;
1309 if (range->compress_type)
1310 compress_type = range->compress_type;
1311 }
1312
1313 if (extent_thresh == 0)
1314 extent_thresh = 256 * 1024;
1315
1316 /*
1317 * if we were not given a file, allocate a readahead
1318 * context
1319 */
1320 if (!file) {
1321 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1322 if (!ra)
1323 return -ENOMEM;
1324 file_ra_state_init(ra, inode->i_mapping);
1325 } else {
1326 ra = &file->f_ra;
1327 }
1328
1329 pages = kmalloc_array(max_cluster, sizeof(struct page *),
1330 GFP_NOFS);
1331 if (!pages) {
1332 ret = -ENOMEM;
1333 goto out_ra;
1334 }
1335
1336 /* find the last page to defrag */
1337 if (range->start + range->len > range->start) {
1338 last_index = min_t(u64, isize - 1,
1339 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1340 } else {
1341 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1342 }
1343
1344 if (newer_than) {
1345 ret = find_new_extents(root, inode, newer_than,
1346 &newer_off, 64 * 1024);
1347 if (!ret) {
1348 range->start = newer_off;
1349 /*
1350 * we always align our defrag to help keep
1351 * the extents in the file evenly spaced
1352 */
1353 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1354 } else
1355 goto out_ra;
1356 } else {
1357 i = range->start >> PAGE_CACHE_SHIFT;
1358 }
1359 if (!max_to_defrag)
1360 max_to_defrag = last_index + 1;
1361
1362 /*
1363 * make writeback starts from i, so the defrag range can be
1364 * written sequentially.
1365 */
1366 if (i < inode->i_mapping->writeback_index)
1367 inode->i_mapping->writeback_index = i;
1368
1369 while (i <= last_index && defrag_count < max_to_defrag &&
1370 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1371 PAGE_CACHE_SHIFT)) {
1372 /*
1373 * make sure we stop running if someone unmounts
1374 * the FS
1375 */
1376 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1377 break;
1378
1379 if (btrfs_defrag_cancelled(root->fs_info)) {
1380 printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n");
1381 ret = -EAGAIN;
1382 break;
1383 }
1384
1385 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1386 extent_thresh, &last_len, &skip,
1387 &defrag_end, range->flags &
1388 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1389 unsigned long next;
1390 /*
1391 * the should_defrag function tells us how much to skip
1392 * bump our counter by the suggested amount
1393 */
1394 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1395 i = max(i + 1, next);
1396 continue;
1397 }
1398
1399 if (!newer_than) {
1400 cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1401 PAGE_CACHE_SHIFT) - i;
1402 cluster = min(cluster, max_cluster);
1403 } else {
1404 cluster = max_cluster;
1405 }
1406
1407 if (i + cluster > ra_index) {
1408 ra_index = max(i, ra_index);
1409 btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1410 cluster);
1411 ra_index += max_cluster;
1412 }
1413
1414 mutex_lock(&inode->i_mutex);
1415 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1416 BTRFS_I(inode)->force_compress = compress_type;
1417 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1418 if (ret < 0) {
1419 mutex_unlock(&inode->i_mutex);
1420 goto out_ra;
1421 }
1422
1423 defrag_count += ret;
1424 balance_dirty_pages_ratelimited(inode->i_mapping);
1425 mutex_unlock(&inode->i_mutex);
1426
1427 if (newer_than) {
1428 if (newer_off == (u64)-1)
1429 break;
1430
1431 if (ret > 0)
1432 i += ret;
1433
1434 newer_off = max(newer_off + 1,
1435 (u64)i << PAGE_CACHE_SHIFT);
1436
1437 ret = find_new_extents(root, inode,
1438 newer_than, &newer_off,
1439 64 * 1024);
1440 if (!ret) {
1441 range->start = newer_off;
1442 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1443 } else {
1444 break;
1445 }
1446 } else {
1447 if (ret > 0) {
1448 i += ret;
1449 last_len += ret << PAGE_CACHE_SHIFT;
1450 } else {
1451 i++;
1452 last_len = 0;
1453 }
1454 }
1455 }
1456
1457 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1458 filemap_flush(inode->i_mapping);
1459 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1460 &BTRFS_I(inode)->runtime_flags))
1461 filemap_flush(inode->i_mapping);
1462 }
1463
1464 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1465 /* the filemap_flush will queue IO into the worker threads, but
1466 * we have to make sure the IO is actually started and that
1467 * ordered extents get created before we return
1468 */
1469 atomic_inc(&root->fs_info->async_submit_draining);
1470 while (atomic_read(&root->fs_info->nr_async_submits) ||
1471 atomic_read(&root->fs_info->async_delalloc_pages)) {
1472 wait_event(root->fs_info->async_submit_wait,
1473 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1474 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1475 }
1476 atomic_dec(&root->fs_info->async_submit_draining);
1477 }
1478
1479 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1480 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1481 }
1482
1483 ret = defrag_count;
1484
1485 out_ra:
1486 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1487 mutex_lock(&inode->i_mutex);
1488 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1489 mutex_unlock(&inode->i_mutex);
1490 }
1491 if (!file)
1492 kfree(ra);
1493 kfree(pages);
1494 return ret;
1495 }
1496
1497 static noinline int btrfs_ioctl_resize(struct file *file,
1498 void __user *arg)
1499 {
1500 u64 new_size;
1501 u64 old_size;
1502 u64 devid = 1;
1503 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
1504 struct btrfs_ioctl_vol_args *vol_args;
1505 struct btrfs_trans_handle *trans;
1506 struct btrfs_device *device = NULL;
1507 char *sizestr;
1508 char *retptr;
1509 char *devstr = NULL;
1510 int ret = 0;
1511 int mod = 0;
1512
1513 if (!capable(CAP_SYS_ADMIN))
1514 return -EPERM;
1515
1516 ret = mnt_want_write_file(file);
1517 if (ret)
1518 return ret;
1519
1520 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1521 1)) {
1522 mnt_drop_write_file(file);
1523 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1524 }
1525
1526 mutex_lock(&root->fs_info->volume_mutex);
1527 vol_args = memdup_user(arg, sizeof(*vol_args));
1528 if (IS_ERR(vol_args)) {
1529 ret = PTR_ERR(vol_args);
1530 goto out;
1531 }
1532
1533 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1534
1535 sizestr = vol_args->name;
1536 devstr = strchr(sizestr, ':');
1537 if (devstr) {
1538 sizestr = devstr + 1;
1539 *devstr = '\0';
1540 devstr = vol_args->name;
1541 ret = kstrtoull(devstr, 10, &devid);
1542 if (ret)
1543 goto out_free;
1544 if (!devid) {
1545 ret = -EINVAL;
1546 goto out_free;
1547 }
1548 btrfs_info(root->fs_info, "resizing devid %llu", devid);
1549 }
1550
1551 device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1552 if (!device) {
1553 btrfs_info(root->fs_info, "resizer unable to find device %llu",
1554 devid);
1555 ret = -ENODEV;
1556 goto out_free;
1557 }
1558
1559 if (!device->writeable) {
1560 btrfs_info(root->fs_info,
1561 "resizer unable to apply on readonly device %llu",
1562 devid);
1563 ret = -EPERM;
1564 goto out_free;
1565 }
1566
1567 if (!strcmp(sizestr, "max"))
1568 new_size = device->bdev->bd_inode->i_size;
1569 else {
1570 if (sizestr[0] == '-') {
1571 mod = -1;
1572 sizestr++;
1573 } else if (sizestr[0] == '+') {
1574 mod = 1;
1575 sizestr++;
1576 }
1577 new_size = memparse(sizestr, &retptr);
1578 if (*retptr != '\0' || new_size == 0) {
1579 ret = -EINVAL;
1580 goto out_free;
1581 }
1582 }
1583
1584 if (device->is_tgtdev_for_dev_replace) {
1585 ret = -EPERM;
1586 goto out_free;
1587 }
1588
1589 old_size = device->total_bytes;
1590
1591 if (mod < 0) {
1592 if (new_size > old_size) {
1593 ret = -EINVAL;
1594 goto out_free;
1595 }
1596 new_size = old_size - new_size;
1597 } else if (mod > 0) {
1598 if (new_size > ULLONG_MAX - old_size) {
1599 ret = -ERANGE;
1600 goto out_free;
1601 }
1602 new_size = old_size + new_size;
1603 }
1604
1605 if (new_size < 256 * 1024 * 1024) {
1606 ret = -EINVAL;
1607 goto out_free;
1608 }
1609 if (new_size > device->bdev->bd_inode->i_size) {
1610 ret = -EFBIG;
1611 goto out_free;
1612 }
1613
1614 do_div(new_size, root->sectorsize);
1615 new_size *= root->sectorsize;
1616
1617 printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n",
1618 rcu_str_deref(device->name), new_size);
1619
1620 if (new_size > old_size) {
1621 trans = btrfs_start_transaction(root, 0);
1622 if (IS_ERR(trans)) {
1623 ret = PTR_ERR(trans);
1624 goto out_free;
1625 }
1626 ret = btrfs_grow_device(trans, device, new_size);
1627 btrfs_commit_transaction(trans, root);
1628 } else if (new_size < old_size) {
1629 ret = btrfs_shrink_device(device, new_size);
1630 } /* equal, nothing need to do */
1631
1632 out_free:
1633 kfree(vol_args);
1634 out:
1635 mutex_unlock(&root->fs_info->volume_mutex);
1636 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1637 mnt_drop_write_file(file);
1638 return ret;
1639 }
1640
1641 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1642 char *name, unsigned long fd, int subvol,
1643 u64 *transid, bool readonly,
1644 struct btrfs_qgroup_inherit *inherit)
1645 {
1646 int namelen;
1647 int ret = 0;
1648
1649 ret = mnt_want_write_file(file);
1650 if (ret)
1651 goto out;
1652
1653 namelen = strlen(name);
1654 if (strchr(name, '/')) {
1655 ret = -EINVAL;
1656 goto out_drop_write;
1657 }
1658
1659 if (name[0] == '.' &&
1660 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1661 ret = -EEXIST;
1662 goto out_drop_write;
1663 }
1664
1665 if (subvol) {
1666 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1667 NULL, transid, readonly, inherit);
1668 } else {
1669 struct fd src = fdget(fd);
1670 struct inode *src_inode;
1671 if (!src.file) {
1672 ret = -EINVAL;
1673 goto out_drop_write;
1674 }
1675
1676 src_inode = file_inode(src.file);
1677 if (src_inode->i_sb != file_inode(file)->i_sb) {
1678 btrfs_info(BTRFS_I(src_inode)->root->fs_info,
1679 "Snapshot src from another FS");
1680 ret = -EXDEV;
1681 } else if (!inode_owner_or_capable(src_inode)) {
1682 /*
1683 * Subvolume creation is not restricted, but snapshots
1684 * are limited to own subvolumes only
1685 */
1686 ret = -EPERM;
1687 } else {
1688 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1689 BTRFS_I(src_inode)->root,
1690 transid, readonly, inherit);
1691 }
1692 fdput(src);
1693 }
1694 out_drop_write:
1695 mnt_drop_write_file(file);
1696 out:
1697 return ret;
1698 }
1699
1700 static noinline int btrfs_ioctl_snap_create(struct file *file,
1701 void __user *arg, int subvol)
1702 {
1703 struct btrfs_ioctl_vol_args *vol_args;
1704 int ret;
1705
1706 vol_args = memdup_user(arg, sizeof(*vol_args));
1707 if (IS_ERR(vol_args))
1708 return PTR_ERR(vol_args);
1709 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1710
1711 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1712 vol_args->fd, subvol,
1713 NULL, false, NULL);
1714
1715 kfree(vol_args);
1716 return ret;
1717 }
1718
1719 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1720 void __user *arg, int subvol)
1721 {
1722 struct btrfs_ioctl_vol_args_v2 *vol_args;
1723 int ret;
1724 u64 transid = 0;
1725 u64 *ptr = NULL;
1726 bool readonly = false;
1727 struct btrfs_qgroup_inherit *inherit = NULL;
1728
1729 vol_args = memdup_user(arg, sizeof(*vol_args));
1730 if (IS_ERR(vol_args))
1731 return PTR_ERR(vol_args);
1732 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1733
1734 if (vol_args->flags &
1735 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1736 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1737 ret = -EOPNOTSUPP;
1738 goto out;
1739 }
1740
1741 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1742 ptr = &transid;
1743 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1744 readonly = true;
1745 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1746 if (vol_args->size > PAGE_CACHE_SIZE) {
1747 ret = -EINVAL;
1748 goto out;
1749 }
1750 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1751 if (IS_ERR(inherit)) {
1752 ret = PTR_ERR(inherit);
1753 goto out;
1754 }
1755 }
1756
1757 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1758 vol_args->fd, subvol, ptr,
1759 readonly, inherit);
1760
1761 if (ret == 0 && ptr &&
1762 copy_to_user(arg +
1763 offsetof(struct btrfs_ioctl_vol_args_v2,
1764 transid), ptr, sizeof(*ptr)))
1765 ret = -EFAULT;
1766 out:
1767 kfree(vol_args);
1768 kfree(inherit);
1769 return ret;
1770 }
1771
1772 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1773 void __user *arg)
1774 {
1775 struct inode *inode = file_inode(file);
1776 struct btrfs_root *root = BTRFS_I(inode)->root;
1777 int ret = 0;
1778 u64 flags = 0;
1779
1780 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1781 return -EINVAL;
1782
1783 down_read(&root->fs_info->subvol_sem);
1784 if (btrfs_root_readonly(root))
1785 flags |= BTRFS_SUBVOL_RDONLY;
1786 up_read(&root->fs_info->subvol_sem);
1787
1788 if (copy_to_user(arg, &flags, sizeof(flags)))
1789 ret = -EFAULT;
1790
1791 return ret;
1792 }
1793
1794 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1795 void __user *arg)
1796 {
1797 struct inode *inode = file_inode(file);
1798 struct btrfs_root *root = BTRFS_I(inode)->root;
1799 struct btrfs_trans_handle *trans;
1800 u64 root_flags;
1801 u64 flags;
1802 int ret = 0;
1803
1804 if (!inode_owner_or_capable(inode))
1805 return -EPERM;
1806
1807 ret = mnt_want_write_file(file);
1808 if (ret)
1809 goto out;
1810
1811 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1812 ret = -EINVAL;
1813 goto out_drop_write;
1814 }
1815
1816 if (copy_from_user(&flags, arg, sizeof(flags))) {
1817 ret = -EFAULT;
1818 goto out_drop_write;
1819 }
1820
1821 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1822 ret = -EINVAL;
1823 goto out_drop_write;
1824 }
1825
1826 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1827 ret = -EOPNOTSUPP;
1828 goto out_drop_write;
1829 }
1830
1831 down_write(&root->fs_info->subvol_sem);
1832
1833 /* nothing to do */
1834 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1835 goto out_drop_sem;
1836
1837 root_flags = btrfs_root_flags(&root->root_item);
1838 if (flags & BTRFS_SUBVOL_RDONLY) {
1839 btrfs_set_root_flags(&root->root_item,
1840 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1841 } else {
1842 /*
1843 * Block RO -> RW transition if this subvolume is involved in
1844 * send
1845 */
1846 spin_lock(&root->root_item_lock);
1847 if (root->send_in_progress == 0) {
1848 btrfs_set_root_flags(&root->root_item,
1849 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1850 spin_unlock(&root->root_item_lock);
1851 } else {
1852 spin_unlock(&root->root_item_lock);
1853 btrfs_warn(root->fs_info,
1854 "Attempt to set subvolume %llu read-write during send",
1855 root->root_key.objectid);
1856 ret = -EPERM;
1857 goto out_drop_sem;
1858 }
1859 }
1860
1861 trans = btrfs_start_transaction(root, 1);
1862 if (IS_ERR(trans)) {
1863 ret = PTR_ERR(trans);
1864 goto out_reset;
1865 }
1866
1867 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1868 &root->root_key, &root->root_item);
1869
1870 btrfs_commit_transaction(trans, root);
1871 out_reset:
1872 if (ret)
1873 btrfs_set_root_flags(&root->root_item, root_flags);
1874 out_drop_sem:
1875 up_write(&root->fs_info->subvol_sem);
1876 out_drop_write:
1877 mnt_drop_write_file(file);
1878 out:
1879 return ret;
1880 }
1881
1882 /*
1883 * helper to check if the subvolume references other subvolumes
1884 */
1885 static noinline int may_destroy_subvol(struct btrfs_root *root)
1886 {
1887 struct btrfs_path *path;
1888 struct btrfs_dir_item *di;
1889 struct btrfs_key key;
1890 u64 dir_id;
1891 int ret;
1892
1893 path = btrfs_alloc_path();
1894 if (!path)
1895 return -ENOMEM;
1896
1897 /* Make sure this root isn't set as the default subvol */
1898 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
1899 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
1900 dir_id, "default", 7, 0);
1901 if (di && !IS_ERR(di)) {
1902 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1903 if (key.objectid == root->root_key.objectid) {
1904 ret = -EPERM;
1905 btrfs_err(root->fs_info, "deleting default subvolume "
1906 "%llu is not allowed", key.objectid);
1907 goto out;
1908 }
1909 btrfs_release_path(path);
1910 }
1911
1912 key.objectid = root->root_key.objectid;
1913 key.type = BTRFS_ROOT_REF_KEY;
1914 key.offset = (u64)-1;
1915
1916 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1917 &key, path, 0, 0);
1918 if (ret < 0)
1919 goto out;
1920 BUG_ON(ret == 0);
1921
1922 ret = 0;
1923 if (path->slots[0] > 0) {
1924 path->slots[0]--;
1925 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1926 if (key.objectid == root->root_key.objectid &&
1927 key.type == BTRFS_ROOT_REF_KEY)
1928 ret = -ENOTEMPTY;
1929 }
1930 out:
1931 btrfs_free_path(path);
1932 return ret;
1933 }
1934
1935 static noinline int key_in_sk(struct btrfs_key *key,
1936 struct btrfs_ioctl_search_key *sk)
1937 {
1938 struct btrfs_key test;
1939 int ret;
1940
1941 test.objectid = sk->min_objectid;
1942 test.type = sk->min_type;
1943 test.offset = sk->min_offset;
1944
1945 ret = btrfs_comp_cpu_keys(key, &test);
1946 if (ret < 0)
1947 return 0;
1948
1949 test.objectid = sk->max_objectid;
1950 test.type = sk->max_type;
1951 test.offset = sk->max_offset;
1952
1953 ret = btrfs_comp_cpu_keys(key, &test);
1954 if (ret > 0)
1955 return 0;
1956 return 1;
1957 }
1958
1959 static noinline int copy_to_sk(struct btrfs_root *root,
1960 struct btrfs_path *path,
1961 struct btrfs_key *key,
1962 struct btrfs_ioctl_search_key *sk,
1963 size_t *buf_size,
1964 char __user *ubuf,
1965 unsigned long *sk_offset,
1966 int *num_found)
1967 {
1968 u64 found_transid;
1969 struct extent_buffer *leaf;
1970 struct btrfs_ioctl_search_header sh;
1971 unsigned long item_off;
1972 unsigned long item_len;
1973 int nritems;
1974 int i;
1975 int slot;
1976 int ret = 0;
1977
1978 leaf = path->nodes[0];
1979 slot = path->slots[0];
1980 nritems = btrfs_header_nritems(leaf);
1981
1982 if (btrfs_header_generation(leaf) > sk->max_transid) {
1983 i = nritems;
1984 goto advance_key;
1985 }
1986 found_transid = btrfs_header_generation(leaf);
1987
1988 for (i = slot; i < nritems; i++) {
1989 item_off = btrfs_item_ptr_offset(leaf, i);
1990 item_len = btrfs_item_size_nr(leaf, i);
1991
1992 btrfs_item_key_to_cpu(leaf, key, i);
1993 if (!key_in_sk(key, sk))
1994 continue;
1995
1996 if (sizeof(sh) + item_len > *buf_size) {
1997 if (*num_found) {
1998 ret = 1;
1999 goto out;
2000 }
2001
2002 /*
2003 * return one empty item back for v1, which does not
2004 * handle -EOVERFLOW
2005 */
2006
2007 *buf_size = sizeof(sh) + item_len;
2008 item_len = 0;
2009 ret = -EOVERFLOW;
2010 }
2011
2012 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2013 ret = 1;
2014 goto out;
2015 }
2016
2017 sh.objectid = key->objectid;
2018 sh.offset = key->offset;
2019 sh.type = key->type;
2020 sh.len = item_len;
2021 sh.transid = found_transid;
2022
2023 /* copy search result header */
2024 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
2025 ret = -EFAULT;
2026 goto out;
2027 }
2028
2029 *sk_offset += sizeof(sh);
2030
2031 if (item_len) {
2032 char __user *up = ubuf + *sk_offset;
2033 /* copy the item */
2034 if (read_extent_buffer_to_user(leaf, up,
2035 item_off, item_len)) {
2036 ret = -EFAULT;
2037 goto out;
2038 }
2039
2040 *sk_offset += item_len;
2041 }
2042 (*num_found)++;
2043
2044 if (ret) /* -EOVERFLOW from above */
2045 goto out;
2046
2047 if (*num_found >= sk->nr_items) {
2048 ret = 1;
2049 goto out;
2050 }
2051 }
2052 advance_key:
2053 ret = 0;
2054 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
2055 key->offset++;
2056 else if (key->type < (u8)-1 && key->type < sk->max_type) {
2057 key->offset = 0;
2058 key->type++;
2059 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
2060 key->offset = 0;
2061 key->type = 0;
2062 key->objectid++;
2063 } else
2064 ret = 1;
2065 out:
2066 /*
2067 * 0: all items from this leaf copied, continue with next
2068 * 1: * more items can be copied, but unused buffer is too small
2069 * * all items were found
2070 * Either way, it will stops the loop which iterates to the next
2071 * leaf
2072 * -EOVERFLOW: item was to large for buffer
2073 * -EFAULT: could not copy extent buffer back to userspace
2074 */
2075 return ret;
2076 }
2077
2078 static noinline int search_ioctl(struct inode *inode,
2079 struct btrfs_ioctl_search_key *sk,
2080 size_t *buf_size,
2081 char __user *ubuf)
2082 {
2083 struct btrfs_root *root;
2084 struct btrfs_key key;
2085 struct btrfs_path *path;
2086 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
2087 int ret;
2088 int num_found = 0;
2089 unsigned long sk_offset = 0;
2090
2091 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2092 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2093 return -EOVERFLOW;
2094 }
2095
2096 path = btrfs_alloc_path();
2097 if (!path)
2098 return -ENOMEM;
2099
2100 if (sk->tree_id == 0) {
2101 /* search the root of the inode that was passed */
2102 root = BTRFS_I(inode)->root;
2103 } else {
2104 key.objectid = sk->tree_id;
2105 key.type = BTRFS_ROOT_ITEM_KEY;
2106 key.offset = (u64)-1;
2107 root = btrfs_read_fs_root_no_name(info, &key);
2108 if (IS_ERR(root)) {
2109 printk(KERN_ERR "BTRFS: could not find root %llu\n",
2110 sk->tree_id);
2111 btrfs_free_path(path);
2112 return -ENOENT;
2113 }
2114 }
2115
2116 key.objectid = sk->min_objectid;
2117 key.type = sk->min_type;
2118 key.offset = sk->min_offset;
2119
2120 path->keep_locks = 1;
2121
2122 while (1) {
2123 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2124 if (ret != 0) {
2125 if (ret > 0)
2126 ret = 0;
2127 goto err;
2128 }
2129 ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf,
2130 &sk_offset, &num_found);
2131 btrfs_release_path(path);
2132 if (ret)
2133 break;
2134
2135 }
2136 if (ret > 0)
2137 ret = 0;
2138 err:
2139 sk->nr_items = num_found;
2140 btrfs_free_path(path);
2141 return ret;
2142 }
2143
2144 static noinline int btrfs_ioctl_tree_search(struct file *file,
2145 void __user *argp)
2146 {
2147 struct btrfs_ioctl_search_args __user *uargs;
2148 struct btrfs_ioctl_search_key sk;
2149 struct inode *inode;
2150 int ret;
2151 size_t buf_size;
2152
2153 if (!capable(CAP_SYS_ADMIN))
2154 return -EPERM;
2155
2156 uargs = (struct btrfs_ioctl_search_args __user *)argp;
2157
2158 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2159 return -EFAULT;
2160
2161 buf_size = sizeof(uargs->buf);
2162
2163 inode = file_inode(file);
2164 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2165
2166 /*
2167 * In the origin implementation an overflow is handled by returning a
2168 * search header with a len of zero, so reset ret.
2169 */
2170 if (ret == -EOVERFLOW)
2171 ret = 0;
2172
2173 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2174 ret = -EFAULT;
2175 return ret;
2176 }
2177
2178 static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2179 void __user *argp)
2180 {
2181 struct btrfs_ioctl_search_args_v2 __user *uarg;
2182 struct btrfs_ioctl_search_args_v2 args;
2183 struct inode *inode;
2184 int ret;
2185 size_t buf_size;
2186 const size_t buf_limit = 16 * 1024 * 1024;
2187
2188 if (!capable(CAP_SYS_ADMIN))
2189 return -EPERM;
2190
2191 /* copy search header and buffer size */
2192 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2193 if (copy_from_user(&args, uarg, sizeof(args)))
2194 return -EFAULT;
2195
2196 buf_size = args.buf_size;
2197
2198 if (buf_size < sizeof(struct btrfs_ioctl_search_header))
2199 return -EOVERFLOW;
2200
2201 /* limit result size to 16MB */
2202 if (buf_size > buf_limit)
2203 buf_size = buf_limit;
2204
2205 inode = file_inode(file);
2206 ret = search_ioctl(inode, &args.key, &buf_size,
2207 (char *)(&uarg->buf[0]));
2208 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2209 ret = -EFAULT;
2210 else if (ret == -EOVERFLOW &&
2211 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2212 ret = -EFAULT;
2213
2214 return ret;
2215 }
2216
2217 /*
2218 * Search INODE_REFs to identify path name of 'dirid' directory
2219 * in a 'tree_id' tree. and sets path name to 'name'.
2220 */
2221 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2222 u64 tree_id, u64 dirid, char *name)
2223 {
2224 struct btrfs_root *root;
2225 struct btrfs_key key;
2226 char *ptr;
2227 int ret = -1;
2228 int slot;
2229 int len;
2230 int total_len = 0;
2231 struct btrfs_inode_ref *iref;
2232 struct extent_buffer *l;
2233 struct btrfs_path *path;
2234
2235 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2236 name[0]='\0';
2237 return 0;
2238 }
2239
2240 path = btrfs_alloc_path();
2241 if (!path)
2242 return -ENOMEM;
2243
2244 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2245
2246 key.objectid = tree_id;
2247 key.type = BTRFS_ROOT_ITEM_KEY;
2248 key.offset = (u64)-1;
2249 root = btrfs_read_fs_root_no_name(info, &key);
2250 if (IS_ERR(root)) {
2251 printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id);
2252 ret = -ENOENT;
2253 goto out;
2254 }
2255
2256 key.objectid = dirid;
2257 key.type = BTRFS_INODE_REF_KEY;
2258 key.offset = (u64)-1;
2259
2260 while (1) {
2261 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2262 if (ret < 0)
2263 goto out;
2264 else if (ret > 0) {
2265 ret = btrfs_previous_item(root, path, dirid,
2266 BTRFS_INODE_REF_KEY);
2267 if (ret < 0)
2268 goto out;
2269 else if (ret > 0) {
2270 ret = -ENOENT;
2271 goto out;
2272 }
2273 }
2274
2275 l = path->nodes[0];
2276 slot = path->slots[0];
2277 btrfs_item_key_to_cpu(l, &key, slot);
2278
2279 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2280 len = btrfs_inode_ref_name_len(l, iref);
2281 ptr -= len + 1;
2282 total_len += len + 1;
2283 if (ptr < name) {
2284 ret = -ENAMETOOLONG;
2285 goto out;
2286 }
2287
2288 *(ptr + len) = '/';
2289 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2290
2291 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2292 break;
2293
2294 btrfs_release_path(path);
2295 key.objectid = key.offset;
2296 key.offset = (u64)-1;
2297 dirid = key.objectid;
2298 }
2299 memmove(name, ptr, total_len);
2300 name[total_len] = '\0';
2301 ret = 0;
2302 out:
2303 btrfs_free_path(path);
2304 return ret;
2305 }
2306
2307 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2308 void __user *argp)
2309 {
2310 struct btrfs_ioctl_ino_lookup_args *args;
2311 struct inode *inode;
2312 int ret;
2313
2314 if (!capable(CAP_SYS_ADMIN))
2315 return -EPERM;
2316
2317 args = memdup_user(argp, sizeof(*args));
2318 if (IS_ERR(args))
2319 return PTR_ERR(args);
2320
2321 inode = file_inode(file);
2322
2323 if (args->treeid == 0)
2324 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2325
2326 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2327 args->treeid, args->objectid,
2328 args->name);
2329
2330 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2331 ret = -EFAULT;
2332
2333 kfree(args);
2334 return ret;
2335 }
2336
2337 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2338 void __user *arg)
2339 {
2340 struct dentry *parent = file->f_path.dentry;
2341 struct dentry *dentry;
2342 struct inode *dir = parent->d_inode;
2343 struct inode *inode;
2344 struct btrfs_root *root = BTRFS_I(dir)->root;
2345 struct btrfs_root *dest = NULL;
2346 struct btrfs_ioctl_vol_args *vol_args;
2347 struct btrfs_trans_handle *trans;
2348 struct btrfs_block_rsv block_rsv;
2349 u64 root_flags;
2350 u64 qgroup_reserved;
2351 int namelen;
2352 int ret;
2353 int err = 0;
2354
2355 vol_args = memdup_user(arg, sizeof(*vol_args));
2356 if (IS_ERR(vol_args))
2357 return PTR_ERR(vol_args);
2358
2359 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2360 namelen = strlen(vol_args->name);
2361 if (strchr(vol_args->name, '/') ||
2362 strncmp(vol_args->name, "..", namelen) == 0) {
2363 err = -EINVAL;
2364 goto out;
2365 }
2366
2367 err = mnt_want_write_file(file);
2368 if (err)
2369 goto out;
2370
2371
2372 err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
2373 if (err == -EINTR)
2374 goto out_drop_write;
2375 dentry = lookup_one_len(vol_args->name, parent, namelen);
2376 if (IS_ERR(dentry)) {
2377 err = PTR_ERR(dentry);
2378 goto out_unlock_dir;
2379 }
2380
2381 if (!dentry->d_inode) {
2382 err = -ENOENT;
2383 goto out_dput;
2384 }
2385
2386 inode = dentry->d_inode;
2387 dest = BTRFS_I(inode)->root;
2388 if (!capable(CAP_SYS_ADMIN)) {
2389 /*
2390 * Regular user. Only allow this with a special mount
2391 * option, when the user has write+exec access to the
2392 * subvol root, and when rmdir(2) would have been
2393 * allowed.
2394 *
2395 * Note that this is _not_ check that the subvol is
2396 * empty or doesn't contain data that we wouldn't
2397 * otherwise be able to delete.
2398 *
2399 * Users who want to delete empty subvols should try
2400 * rmdir(2).
2401 */
2402 err = -EPERM;
2403 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2404 goto out_dput;
2405
2406 /*
2407 * Do not allow deletion if the parent dir is the same
2408 * as the dir to be deleted. That means the ioctl
2409 * must be called on the dentry referencing the root
2410 * of the subvol, not a random directory contained
2411 * within it.
2412 */
2413 err = -EINVAL;
2414 if (root == dest)
2415 goto out_dput;
2416
2417 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2418 if (err)
2419 goto out_dput;
2420 }
2421
2422 /* check if subvolume may be deleted by a user */
2423 err = btrfs_may_delete(dir, dentry, 1);
2424 if (err)
2425 goto out_dput;
2426
2427 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2428 err = -EINVAL;
2429 goto out_dput;
2430 }
2431
2432 mutex_lock(&inode->i_mutex);
2433
2434 /*
2435 * Don't allow to delete a subvolume with send in progress. This is
2436 * inside the i_mutex so the error handling that has to drop the bit
2437 * again is not run concurrently.
2438 */
2439 spin_lock(&dest->root_item_lock);
2440 root_flags = btrfs_root_flags(&dest->root_item);
2441 if (dest->send_in_progress == 0) {
2442 btrfs_set_root_flags(&dest->root_item,
2443 root_flags | BTRFS_ROOT_SUBVOL_DEAD);
2444 spin_unlock(&dest->root_item_lock);
2445 } else {
2446 spin_unlock(&dest->root_item_lock);
2447 btrfs_warn(root->fs_info,
2448 "Attempt to delete subvolume %llu during send",
2449 dest->root_key.objectid);
2450 err = -EPERM;
2451 goto out_dput;
2452 }
2453
2454 err = d_invalidate(dentry);
2455 if (err)
2456 goto out_unlock;
2457
2458 down_write(&root->fs_info->subvol_sem);
2459
2460 err = may_destroy_subvol(dest);
2461 if (err)
2462 goto out_up_write;
2463
2464 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2465 /*
2466 * One for dir inode, two for dir entries, two for root
2467 * ref/backref.
2468 */
2469 err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2470 5, &qgroup_reserved, true);
2471 if (err)
2472 goto out_up_write;
2473
2474 trans = btrfs_start_transaction(root, 0);
2475 if (IS_ERR(trans)) {
2476 err = PTR_ERR(trans);
2477 goto out_release;
2478 }
2479 trans->block_rsv = &block_rsv;
2480 trans->bytes_reserved = block_rsv.size;
2481
2482 ret = btrfs_unlink_subvol(trans, root, dir,
2483 dest->root_key.objectid,
2484 dentry->d_name.name,
2485 dentry->d_name.len);
2486 if (ret) {
2487 err = ret;
2488 btrfs_abort_transaction(trans, root, ret);
2489 goto out_end_trans;
2490 }
2491
2492 btrfs_record_root_in_trans(trans, dest);
2493
2494 memset(&dest->root_item.drop_progress, 0,
2495 sizeof(dest->root_item.drop_progress));
2496 dest->root_item.drop_level = 0;
2497 btrfs_set_root_refs(&dest->root_item, 0);
2498
2499 if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
2500 ret = btrfs_insert_orphan_item(trans,
2501 root->fs_info->tree_root,
2502 dest->root_key.objectid);
2503 if (ret) {
2504 btrfs_abort_transaction(trans, root, ret);
2505 err = ret;
2506 goto out_end_trans;
2507 }
2508 }
2509
2510 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2511 dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
2512 dest->root_key.objectid);
2513 if (ret && ret != -ENOENT) {
2514 btrfs_abort_transaction(trans, root, ret);
2515 err = ret;
2516 goto out_end_trans;
2517 }
2518 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
2519 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2520 dest->root_item.received_uuid,
2521 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
2522 dest->root_key.objectid);
2523 if (ret && ret != -ENOENT) {
2524 btrfs_abort_transaction(trans, root, ret);
2525 err = ret;
2526 goto out_end_trans;
2527 }
2528 }
2529
2530 out_end_trans:
2531 trans->block_rsv = NULL;
2532 trans->bytes_reserved = 0;
2533 ret = btrfs_end_transaction(trans, root);
2534 if (ret && !err)
2535 err = ret;
2536 inode->i_flags |= S_DEAD;
2537 out_release:
2538 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2539 out_up_write:
2540 up_write(&root->fs_info->subvol_sem);
2541 out_unlock:
2542 if (err) {
2543 spin_lock(&dest->root_item_lock);
2544 root_flags = btrfs_root_flags(&dest->root_item);
2545 btrfs_set_root_flags(&dest->root_item,
2546 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
2547 spin_unlock(&dest->root_item_lock);
2548 }
2549 mutex_unlock(&inode->i_mutex);
2550 if (!err) {
2551 shrink_dcache_sb(root->fs_info->sb);
2552 btrfs_invalidate_inodes(dest);
2553 d_delete(dentry);
2554 ASSERT(dest->send_in_progress == 0);
2555
2556 /* the last ref */
2557 if (dest->cache_inode) {
2558 iput(dest->cache_inode);
2559 dest->cache_inode = NULL;
2560 }
2561 }
2562 out_dput:
2563 dput(dentry);
2564 out_unlock_dir:
2565 mutex_unlock(&dir->i_mutex);
2566 out_drop_write:
2567 mnt_drop_write_file(file);
2568 out:
2569 kfree(vol_args);
2570 return err;
2571 }
2572
2573 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2574 {
2575 struct inode *inode = file_inode(file);
2576 struct btrfs_root *root = BTRFS_I(inode)->root;
2577 struct btrfs_ioctl_defrag_range_args *range;
2578 int ret;
2579
2580 ret = mnt_want_write_file(file);
2581 if (ret)
2582 return ret;
2583
2584 if (btrfs_root_readonly(root)) {
2585 ret = -EROFS;
2586 goto out;
2587 }
2588
2589 switch (inode->i_mode & S_IFMT) {
2590 case S_IFDIR:
2591 if (!capable(CAP_SYS_ADMIN)) {
2592 ret = -EPERM;
2593 goto out;
2594 }
2595 ret = btrfs_defrag_root(root);
2596 if (ret)
2597 goto out;
2598 ret = btrfs_defrag_root(root->fs_info->extent_root);
2599 break;
2600 case S_IFREG:
2601 if (!(file->f_mode & FMODE_WRITE)) {
2602 ret = -EINVAL;
2603 goto out;
2604 }
2605
2606 range = kzalloc(sizeof(*range), GFP_KERNEL);
2607 if (!range) {
2608 ret = -ENOMEM;
2609 goto out;
2610 }
2611
2612 if (argp) {
2613 if (copy_from_user(range, argp,
2614 sizeof(*range))) {
2615 ret = -EFAULT;
2616 kfree(range);
2617 goto out;
2618 }
2619 /* compression requires us to start the IO */
2620 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2621 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2622 range->extent_thresh = (u32)-1;
2623 }
2624 } else {
2625 /* the rest are all set to zero by kzalloc */
2626 range->len = (u64)-1;
2627 }
2628 ret = btrfs_defrag_file(file_inode(file), file,
2629 range, 0, 0);
2630 if (ret > 0)
2631 ret = 0;
2632 kfree(range);
2633 break;
2634 default:
2635 ret = -EINVAL;
2636 }
2637 out:
2638 mnt_drop_write_file(file);
2639 return ret;
2640 }
2641
2642 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2643 {
2644 struct btrfs_ioctl_vol_args *vol_args;
2645 int ret;
2646
2647 if (!capable(CAP_SYS_ADMIN))
2648 return -EPERM;
2649
2650 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2651 1)) {
2652 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2653 }
2654
2655 mutex_lock(&root->fs_info->volume_mutex);
2656 vol_args = memdup_user(arg, sizeof(*vol_args));
2657 if (IS_ERR(vol_args)) {
2658 ret = PTR_ERR(vol_args);
2659 goto out;
2660 }
2661
2662 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2663 ret = btrfs_init_new_device(root, vol_args->name);
2664
2665 kfree(vol_args);
2666 out:
2667 mutex_unlock(&root->fs_info->volume_mutex);
2668 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2669 return ret;
2670 }
2671
2672 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2673 {
2674 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
2675 struct btrfs_ioctl_vol_args *vol_args;
2676 int ret;
2677
2678 if (!capable(CAP_SYS_ADMIN))
2679 return -EPERM;
2680
2681 ret = mnt_want_write_file(file);
2682 if (ret)
2683 return ret;
2684
2685 vol_args = memdup_user(arg, sizeof(*vol_args));
2686 if (IS_ERR(vol_args)) {
2687 ret = PTR_ERR(vol_args);
2688 goto out;
2689 }
2690
2691 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2692
2693 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2694 1)) {
2695 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2696 goto out;
2697 }
2698
2699 mutex_lock(&root->fs_info->volume_mutex);
2700 ret = btrfs_rm_device(root, vol_args->name);
2701 mutex_unlock(&root->fs_info->volume_mutex);
2702 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2703
2704 out:
2705 kfree(vol_args);
2706 mnt_drop_write_file(file);
2707 return ret;
2708 }
2709
2710 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2711 {
2712 struct btrfs_ioctl_fs_info_args *fi_args;
2713 struct btrfs_device *device;
2714 struct btrfs_device *next;
2715 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2716 int ret = 0;
2717
2718 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2719 if (!fi_args)
2720 return -ENOMEM;
2721
2722 mutex_lock(&fs_devices->device_list_mutex);
2723 fi_args->num_devices = fs_devices->num_devices;
2724 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2725
2726 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2727 if (device->devid > fi_args->max_id)
2728 fi_args->max_id = device->devid;
2729 }
2730 mutex_unlock(&fs_devices->device_list_mutex);
2731
2732 fi_args->nodesize = root->fs_info->super_copy->nodesize;
2733 fi_args->sectorsize = root->fs_info->super_copy->sectorsize;
2734 fi_args->clone_alignment = root->fs_info->super_copy->sectorsize;
2735
2736 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2737 ret = -EFAULT;
2738
2739 kfree(fi_args);
2740 return ret;
2741 }
2742
2743 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2744 {
2745 struct btrfs_ioctl_dev_info_args *di_args;
2746 struct btrfs_device *dev;
2747 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2748 int ret = 0;
2749 char *s_uuid = NULL;
2750
2751 di_args = memdup_user(arg, sizeof(*di_args));
2752 if (IS_ERR(di_args))
2753 return PTR_ERR(di_args);
2754
2755 if (!btrfs_is_empty_uuid(di_args->uuid))
2756 s_uuid = di_args->uuid;
2757
2758 mutex_lock(&fs_devices->device_list_mutex);
2759 dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2760
2761 if (!dev) {
2762 ret = -ENODEV;
2763 goto out;
2764 }
2765
2766 di_args->devid = dev->devid;
2767 di_args->bytes_used = dev->bytes_used;
2768 di_args->total_bytes = dev->total_bytes;
2769 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2770 if (dev->name) {
2771 struct rcu_string *name;
2772
2773 rcu_read_lock();
2774 name = rcu_dereference(dev->name);
2775 strncpy(di_args->path, name->str, sizeof(di_args->path));
2776 rcu_read_unlock();
2777 di_args->path[sizeof(di_args->path) - 1] = 0;
2778 } else {
2779 di_args->path[0] = '\0';
2780 }
2781
2782 out:
2783 mutex_unlock(&fs_devices->device_list_mutex);
2784 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2785 ret = -EFAULT;
2786
2787 kfree(di_args);
2788 return ret;
2789 }
2790
2791 static struct page *extent_same_get_page(struct inode *inode, u64 off)
2792 {
2793 struct page *page;
2794 pgoff_t index;
2795 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
2796
2797 index = off >> PAGE_CACHE_SHIFT;
2798
2799 page = grab_cache_page(inode->i_mapping, index);
2800 if (!page)
2801 return NULL;
2802
2803 if (!PageUptodate(page)) {
2804 if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
2805 0))
2806 return NULL;
2807 lock_page(page);
2808 if (!PageUptodate(page)) {
2809 unlock_page(page);
2810 page_cache_release(page);
2811 return NULL;
2812 }
2813 }
2814 unlock_page(page);
2815
2816 return page;
2817 }
2818
2819 static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
2820 {
2821 /* do any pending delalloc/csum calc on src, one way or
2822 another, and lock file content */
2823 while (1) {
2824 struct btrfs_ordered_extent *ordered;
2825 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2826 ordered = btrfs_lookup_first_ordered_extent(inode,
2827 off + len - 1);
2828 if ((!ordered ||
2829 ordered->file_offset + ordered->len <= off ||
2830 ordered->file_offset >= off + len) &&
2831 !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2832 off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
2833 if (ordered)
2834 btrfs_put_ordered_extent(ordered);
2835 break;
2836 }
2837 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2838 if (ordered)
2839 btrfs_put_ordered_extent(ordered);
2840 btrfs_wait_ordered_range(inode, off, len);
2841 }
2842 }
2843
2844 static void btrfs_double_unlock(struct inode *inode1, u64 loff1,
2845 struct inode *inode2, u64 loff2, u64 len)
2846 {
2847 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
2848 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
2849
2850 mutex_unlock(&inode1->i_mutex);
2851 mutex_unlock(&inode2->i_mutex);
2852 }
2853
2854 static void btrfs_double_lock(struct inode *inode1, u64 loff1,
2855 struct inode *inode2, u64 loff2, u64 len)
2856 {
2857 if (inode1 < inode2) {
2858 swap(inode1, inode2);
2859 swap(loff1, loff2);
2860 }
2861
2862 mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
2863 lock_extent_range(inode1, loff1, len);
2864 if (inode1 != inode2) {
2865 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
2866 lock_extent_range(inode2, loff2, len);
2867 }
2868 }
2869
2870 static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
2871 u64 dst_loff, u64 len)
2872 {
2873 int ret = 0;
2874 struct page *src_page, *dst_page;
2875 unsigned int cmp_len = PAGE_CACHE_SIZE;
2876 void *addr, *dst_addr;
2877
2878 while (len) {
2879 if (len < PAGE_CACHE_SIZE)
2880 cmp_len = len;
2881
2882 src_page = extent_same_get_page(src, loff);
2883 if (!src_page)
2884 return -EINVAL;
2885 dst_page = extent_same_get_page(dst, dst_loff);
2886 if (!dst_page) {
2887 page_cache_release(src_page);
2888 return -EINVAL;
2889 }
2890 addr = kmap_atomic(src_page);
2891 dst_addr = kmap_atomic(dst_page);
2892
2893 flush_dcache_page(src_page);
2894 flush_dcache_page(dst_page);
2895
2896 if (memcmp(addr, dst_addr, cmp_len))
2897 ret = BTRFS_SAME_DATA_DIFFERS;
2898
2899 kunmap_atomic(addr);
2900 kunmap_atomic(dst_addr);
2901 page_cache_release(src_page);
2902 page_cache_release(dst_page);
2903
2904 if (ret)
2905 break;
2906
2907 loff += cmp_len;
2908 dst_loff += cmp_len;
2909 len -= cmp_len;
2910 }
2911
2912 return ret;
2913 }
2914
2915 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len)
2916 {
2917 u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
2918
2919 if (off + len > inode->i_size || off + len < off)
2920 return -EINVAL;
2921 /* Check that we are block aligned - btrfs_clone() requires this */
2922 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
2923 return -EINVAL;
2924
2925 return 0;
2926 }
2927
2928 static int btrfs_extent_same(struct inode *src, u64 loff, u64 len,
2929 struct inode *dst, u64 dst_loff)
2930 {
2931 int ret;
2932
2933 /*
2934 * btrfs_clone() can't handle extents in the same file
2935 * yet. Once that works, we can drop this check and replace it
2936 * with a check for the same inode, but overlapping extents.
2937 */
2938 if (src == dst)
2939 return -EINVAL;
2940
2941 btrfs_double_lock(src, loff, dst, dst_loff, len);
2942
2943 ret = extent_same_check_offsets(src, loff, len);
2944 if (ret)
2945 goto out_unlock;
2946
2947 ret = extent_same_check_offsets(dst, dst_loff, len);
2948 if (ret)
2949 goto out_unlock;
2950
2951 /* don't make the dst file partly checksummed */
2952 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2953 (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
2954 ret = -EINVAL;
2955 goto out_unlock;
2956 }
2957
2958 ret = btrfs_cmp_data(src, loff, dst, dst_loff, len);
2959 if (ret == 0)
2960 ret = btrfs_clone(src, dst, loff, len, len, dst_loff);
2961
2962 out_unlock:
2963 btrfs_double_unlock(src, loff, dst, dst_loff, len);
2964
2965 return ret;
2966 }
2967
2968 #define BTRFS_MAX_DEDUPE_LEN (16 * 1024 * 1024)
2969
2970 static long btrfs_ioctl_file_extent_same(struct file *file,
2971 struct btrfs_ioctl_same_args __user *argp)
2972 {
2973 struct btrfs_ioctl_same_args *same;
2974 struct btrfs_ioctl_same_extent_info *info;
2975 struct inode *src = file_inode(file);
2976 u64 off;
2977 u64 len;
2978 int i;
2979 int ret;
2980 unsigned long size;
2981 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
2982 bool is_admin = capable(CAP_SYS_ADMIN);
2983 u16 count;
2984
2985 if (!(file->f_mode & FMODE_READ))
2986 return -EINVAL;
2987
2988 ret = mnt_want_write_file(file);
2989 if (ret)
2990 return ret;
2991
2992 if (get_user(count, &argp->dest_count)) {
2993 ret = -EFAULT;
2994 goto out;
2995 }
2996
2997 size = offsetof(struct btrfs_ioctl_same_args __user, info[count]);
2998
2999 same = memdup_user(argp, size);
3000
3001 if (IS_ERR(same)) {
3002 ret = PTR_ERR(same);
3003 goto out;
3004 }
3005
3006 off = same->logical_offset;
3007 len = same->length;
3008
3009 /*
3010 * Limit the total length we will dedupe for each operation.
3011 * This is intended to bound the total time spent in this
3012 * ioctl to something sane.
3013 */
3014 if (len > BTRFS_MAX_DEDUPE_LEN)
3015 len = BTRFS_MAX_DEDUPE_LEN;
3016
3017 if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
3018 /*
3019 * Btrfs does not support blocksize < page_size. As a
3020 * result, btrfs_cmp_data() won't correctly handle
3021 * this situation without an update.
3022 */
3023 ret = -EINVAL;
3024 goto out;
3025 }
3026
3027 ret = -EISDIR;
3028 if (S_ISDIR(src->i_mode))
3029 goto out;
3030
3031 ret = -EACCES;
3032 if (!S_ISREG(src->i_mode))
3033 goto out;
3034
3035 /* pre-format output fields to sane values */
3036 for (i = 0; i < count; i++) {
3037 same->info[i].bytes_deduped = 0ULL;
3038 same->info[i].status = 0;
3039 }
3040
3041 for (i = 0, info = same->info; i < count; i++, info++) {
3042 struct inode *dst;
3043 struct fd dst_file = fdget(info->fd);
3044 if (!dst_file.file) {
3045 info->status = -EBADF;
3046 continue;
3047 }
3048 dst = file_inode(dst_file.file);
3049
3050 if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) {
3051 info->status = -EINVAL;
3052 } else if (file->f_path.mnt != dst_file.file->f_path.mnt) {
3053 info->status = -EXDEV;
3054 } else if (S_ISDIR(dst->i_mode)) {
3055 info->status = -EISDIR;
3056 } else if (!S_ISREG(dst->i_mode)) {
3057 info->status = -EACCES;
3058 } else {
3059 info->status = btrfs_extent_same(src, off, len, dst,
3060 info->logical_offset);
3061 if (info->status == 0)
3062 info->bytes_deduped += len;
3063 }
3064 fdput(dst_file);
3065 }
3066
3067 ret = copy_to_user(argp, same, size);
3068 if (ret)
3069 ret = -EFAULT;
3070
3071 out:
3072 mnt_drop_write_file(file);
3073 return ret;
3074 }
3075
3076 /* Helper to check and see if this root currently has a ref on the given disk
3077 * bytenr. If it does then we need to update the quota for this root. This
3078 * doesn't do anything if quotas aren't enabled.
3079 */
3080 static int check_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3081 u64 disko)
3082 {
3083 struct seq_list tree_mod_seq_elem = {};
3084 struct ulist *roots;
3085 struct ulist_iterator uiter;
3086 struct ulist_node *root_node = NULL;
3087 int ret;
3088
3089 if (!root->fs_info->quota_enabled)
3090 return 1;
3091
3092 btrfs_get_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3093 ret = btrfs_find_all_roots(trans, root->fs_info, disko,
3094 tree_mod_seq_elem.seq, &roots);
3095 if (ret < 0)
3096 goto out;
3097 ret = 0;
3098 ULIST_ITER_INIT(&uiter);
3099 while ((root_node = ulist_next(roots, &uiter))) {
3100 if (root_node->val == root->objectid) {
3101 ret = 1;
3102 break;
3103 }
3104 }
3105 ulist_free(roots);
3106 out:
3107 btrfs_put_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3108 return ret;
3109 }
3110
3111 static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3112 struct inode *inode,
3113 u64 endoff,
3114 const u64 destoff,
3115 const u64 olen)
3116 {
3117 struct btrfs_root *root = BTRFS_I(inode)->root;
3118 int ret;
3119
3120 inode_inc_iversion(inode);
3121 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3122 /*
3123 * We round up to the block size at eof when determining which
3124 * extents to clone above, but shouldn't round up the file size.
3125 */
3126 if (endoff > destoff + olen)
3127 endoff = destoff + olen;
3128 if (endoff > inode->i_size)
3129 btrfs_i_size_write(inode, endoff);
3130
3131 ret = btrfs_update_inode(trans, root, inode);
3132 if (ret) {
3133 btrfs_abort_transaction(trans, root, ret);
3134 btrfs_end_transaction(trans, root);
3135 goto out;
3136 }
3137 ret = btrfs_end_transaction(trans, root);
3138 out:
3139 return ret;
3140 }
3141
3142 static void clone_update_extent_map(struct inode *inode,
3143 const struct btrfs_trans_handle *trans,
3144 const struct btrfs_path *path,
3145 const u64 hole_offset,
3146 const u64 hole_len)
3147 {
3148 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
3149 struct extent_map *em;
3150 int ret;
3151
3152 em = alloc_extent_map();
3153 if (!em) {
3154 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3155 &BTRFS_I(inode)->runtime_flags);
3156 return;
3157 }
3158
3159 if (path) {
3160 struct btrfs_file_extent_item *fi;
3161
3162 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
3163 struct btrfs_file_extent_item);
3164 btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
3165 em->generation = -1;
3166 if (btrfs_file_extent_type(path->nodes[0], fi) ==
3167 BTRFS_FILE_EXTENT_INLINE)
3168 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3169 &BTRFS_I(inode)->runtime_flags);
3170 } else {
3171 em->start = hole_offset;
3172 em->len = hole_len;
3173 em->ram_bytes = em->len;
3174 em->orig_start = hole_offset;
3175 em->block_start = EXTENT_MAP_HOLE;
3176 em->block_len = 0;
3177 em->orig_block_len = 0;
3178 em->compress_type = BTRFS_COMPRESS_NONE;
3179 em->generation = trans->transid;
3180 }
3181
3182 while (1) {
3183 write_lock(&em_tree->lock);
3184 ret = add_extent_mapping(em_tree, em, 1);
3185 write_unlock(&em_tree->lock);
3186 if (ret != -EEXIST) {
3187 free_extent_map(em);
3188 break;
3189 }
3190 btrfs_drop_extent_cache(inode, em->start,
3191 em->start + em->len - 1, 0);
3192 }
3193
3194 if (unlikely(ret))
3195 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3196 &BTRFS_I(inode)->runtime_flags);
3197 }
3198
3199 /**
3200 * btrfs_clone() - clone a range from inode file to another
3201 *
3202 * @src: Inode to clone from
3203 * @inode: Inode to clone to
3204 * @off: Offset within source to start clone from
3205 * @olen: Original length, passed by user, of range to clone
3206 * @olen_aligned: Block-aligned value of olen, extent_same uses
3207 * identical values here
3208 * @destoff: Offset within @inode to start clone
3209 */
3210 static int btrfs_clone(struct inode *src, struct inode *inode,
3211 const u64 off, const u64 olen, const u64 olen_aligned,
3212 const u64 destoff)
3213 {
3214 struct btrfs_root *root = BTRFS_I(inode)->root;
3215 struct btrfs_path *path = NULL;
3216 struct extent_buffer *leaf;
3217 struct btrfs_trans_handle *trans;
3218 char *buf = NULL;
3219 struct btrfs_key key;
3220 u32 nritems;
3221 int slot;
3222 int ret;
3223 int no_quota;
3224 const u64 len = olen_aligned;
3225 u64 last_disko = 0;
3226 u64 last_dest_end = destoff;
3227
3228 ret = -ENOMEM;
3229 buf = vmalloc(btrfs_level_size(root, 0));
3230 if (!buf)
3231 return ret;
3232
3233 path = btrfs_alloc_path();
3234 if (!path) {
3235 vfree(buf);
3236 return ret;
3237 }
3238
3239 path->reada = 2;
3240 /* clone data */
3241 key.objectid = btrfs_ino(src);
3242 key.type = BTRFS_EXTENT_DATA_KEY;
3243 key.offset = off;
3244
3245 while (1) {
3246 /*
3247 * note the key will change type as we walk through the
3248 * tree.
3249 */
3250 path->leave_spinning = 1;
3251 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3252 0, 0);
3253 if (ret < 0)
3254 goto out;
3255 /*
3256 * First search, if no extent item that starts at offset off was
3257 * found but the previous item is an extent item, it's possible
3258 * it might overlap our target range, therefore process it.
3259 */
3260 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3261 btrfs_item_key_to_cpu(path->nodes[0], &key,
3262 path->slots[0] - 1);
3263 if (key.type == BTRFS_EXTENT_DATA_KEY)
3264 path->slots[0]--;
3265 }
3266
3267 nritems = btrfs_header_nritems(path->nodes[0]);
3268 process_slot:
3269 no_quota = 1;
3270 if (path->slots[0] >= nritems) {
3271 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3272 if (ret < 0)
3273 goto out;
3274 if (ret > 0)
3275 break;
3276 nritems = btrfs_header_nritems(path->nodes[0]);
3277 }
3278 leaf = path->nodes[0];
3279 slot = path->slots[0];
3280
3281 btrfs_item_key_to_cpu(leaf, &key, slot);
3282 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
3283 key.objectid != btrfs_ino(src))
3284 break;
3285
3286 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
3287 struct btrfs_file_extent_item *extent;
3288 int type;
3289 u32 size;
3290 struct btrfs_key new_key;
3291 u64 disko = 0, diskl = 0;
3292 u64 datao = 0, datal = 0;
3293 u8 comp;
3294 u64 drop_start;
3295
3296 extent = btrfs_item_ptr(leaf, slot,
3297 struct btrfs_file_extent_item);
3298 comp = btrfs_file_extent_compression(leaf, extent);
3299 type = btrfs_file_extent_type(leaf, extent);
3300 if (type == BTRFS_FILE_EXTENT_REG ||
3301 type == BTRFS_FILE_EXTENT_PREALLOC) {
3302 disko = btrfs_file_extent_disk_bytenr(leaf,
3303 extent);
3304 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3305 extent);
3306 datao = btrfs_file_extent_offset(leaf, extent);
3307 datal = btrfs_file_extent_num_bytes(leaf,
3308 extent);
3309 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3310 /* take upper bound, may be compressed */
3311 datal = btrfs_file_extent_ram_bytes(leaf,
3312 extent);
3313 }
3314
3315 /*
3316 * The first search might have left us at an extent
3317 * item that ends before our target range's start, can
3318 * happen if we have holes and NO_HOLES feature enabled.
3319 */
3320 if (key.offset + datal <= off) {
3321 path->slots[0]++;
3322 goto process_slot;
3323 } else if (key.offset >= off + len) {
3324 break;
3325 }
3326
3327 size = btrfs_item_size_nr(leaf, slot);
3328 read_extent_buffer(leaf, buf,
3329 btrfs_item_ptr_offset(leaf, slot),
3330 size);
3331
3332 btrfs_release_path(path);
3333 path->leave_spinning = 0;
3334
3335 memcpy(&new_key, &key, sizeof(new_key));
3336 new_key.objectid = btrfs_ino(inode);
3337 if (off <= key.offset)
3338 new_key.offset = key.offset + destoff - off;
3339 else
3340 new_key.offset = destoff;
3341
3342 /*
3343 * Deal with a hole that doesn't have an extent item
3344 * that represents it (NO_HOLES feature enabled).
3345 * This hole is either in the middle of the cloning
3346 * range or at the beginning (fully overlaps it or
3347 * partially overlaps it).
3348 */
3349 if (new_key.offset != last_dest_end)
3350 drop_start = last_dest_end;
3351 else
3352 drop_start = new_key.offset;
3353
3354 /*
3355 * 1 - adjusting old extent (we may have to split it)
3356 * 1 - add new extent
3357 * 1 - inode update
3358 */
3359 trans = btrfs_start_transaction(root, 3);
3360 if (IS_ERR(trans)) {
3361 ret = PTR_ERR(trans);
3362 goto out;
3363 }
3364
3365 if (type == BTRFS_FILE_EXTENT_REG ||
3366 type == BTRFS_FILE_EXTENT_PREALLOC) {
3367 /*
3368 * a | --- range to clone ---| b
3369 * | ------------- extent ------------- |
3370 */
3371
3372 /* subtract range b */
3373 if (key.offset + datal > off + len)
3374 datal = off + len - key.offset;
3375
3376 /* subtract range a */
3377 if (off > key.offset) {
3378 datao += off - key.offset;
3379 datal -= off - key.offset;
3380 }
3381
3382 ret = btrfs_drop_extents(trans, root, inode,
3383 drop_start,
3384 new_key.offset + datal,
3385 1);
3386 if (ret) {
3387 if (ret != -EOPNOTSUPP)
3388 btrfs_abort_transaction(trans,
3389 root, ret);
3390 btrfs_end_transaction(trans, root);
3391 goto out;
3392 }
3393
3394 ret = btrfs_insert_empty_item(trans, root, path,
3395 &new_key, size);
3396 if (ret) {
3397 btrfs_abort_transaction(trans, root,
3398 ret);
3399 btrfs_end_transaction(trans, root);
3400 goto out;
3401 }
3402
3403 leaf = path->nodes[0];
3404 slot = path->slots[0];
3405 write_extent_buffer(leaf, buf,
3406 btrfs_item_ptr_offset(leaf, slot),
3407 size);
3408
3409 extent = btrfs_item_ptr(leaf, slot,
3410 struct btrfs_file_extent_item);
3411
3412 /* disko == 0 means it's a hole */
3413 if (!disko)
3414 datao = 0;
3415
3416 btrfs_set_file_extent_offset(leaf, extent,
3417 datao);
3418 btrfs_set_file_extent_num_bytes(leaf, extent,
3419 datal);
3420
3421 /*
3422 * We need to look up the roots that point at
3423 * this bytenr and see if the new root does. If
3424 * it does not we need to make sure we update
3425 * quotas appropriately.
3426 */
3427 if (disko && root != BTRFS_I(src)->root &&
3428 disko != last_disko) {
3429 no_quota = check_ref(trans, root,
3430 disko);
3431 if (no_quota < 0) {
3432 btrfs_abort_transaction(trans,
3433 root,
3434 ret);
3435 btrfs_end_transaction(trans,
3436 root);
3437 ret = no_quota;
3438 goto out;
3439 }
3440 }
3441
3442 if (disko) {
3443 inode_add_bytes(inode, datal);
3444 ret = btrfs_inc_extent_ref(trans, root,
3445 disko, diskl, 0,
3446 root->root_key.objectid,
3447 btrfs_ino(inode),
3448 new_key.offset - datao,
3449 no_quota);
3450 if (ret) {
3451 btrfs_abort_transaction(trans,
3452 root,
3453 ret);
3454 btrfs_end_transaction(trans,
3455 root);
3456 goto out;
3457
3458 }
3459 }
3460 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3461 u64 skip = 0;
3462 u64 trim = 0;
3463 u64 aligned_end = 0;
3464
3465 if (off > key.offset) {
3466 skip = off - key.offset;
3467 new_key.offset += skip;
3468 }
3469
3470 if (key.offset + datal > off + len)
3471 trim = key.offset + datal - (off + len);
3472
3473 if (comp && (skip || trim)) {
3474 ret = -EINVAL;
3475 btrfs_end_transaction(trans, root);
3476 goto out;
3477 }
3478 size -= skip + trim;
3479 datal -= skip + trim;
3480
3481 aligned_end = ALIGN(new_key.offset + datal,
3482 root->sectorsize);
3483 ret = btrfs_drop_extents(trans, root, inode,
3484 drop_start,
3485 aligned_end,
3486 1);
3487 if (ret) {
3488 if (ret != -EOPNOTSUPP)
3489 btrfs_abort_transaction(trans,
3490 root, ret);
3491 btrfs_end_transaction(trans, root);
3492 goto out;
3493 }
3494
3495 ret = btrfs_insert_empty_item(trans, root, path,
3496 &new_key, size);
3497 if (ret) {
3498 btrfs_abort_transaction(trans, root,
3499 ret);
3500 btrfs_end_transaction(trans, root);
3501 goto out;
3502 }
3503
3504 if (skip) {
3505 u32 start =
3506 btrfs_file_extent_calc_inline_size(0);
3507 memmove(buf+start, buf+start+skip,
3508 datal);
3509 }
3510
3511 leaf = path->nodes[0];
3512 slot = path->slots[0];
3513 write_extent_buffer(leaf, buf,
3514 btrfs_item_ptr_offset(leaf, slot),
3515 size);
3516 inode_add_bytes(inode, datal);
3517 }
3518
3519 /* If we have an implicit hole (NO_HOLES feature). */
3520 if (drop_start < new_key.offset)
3521 clone_update_extent_map(inode, trans,
3522 NULL, drop_start,
3523 new_key.offset - drop_start);
3524
3525 clone_update_extent_map(inode, trans, path, 0, 0);
3526
3527 btrfs_mark_buffer_dirty(leaf);
3528 btrfs_release_path(path);
3529
3530 last_dest_end = new_key.offset + datal;
3531 ret = clone_finish_inode_update(trans, inode,
3532 last_dest_end,
3533 destoff, olen);
3534 if (ret)
3535 goto out;
3536 if (new_key.offset + datal >= destoff + len)
3537 break;
3538 }
3539 btrfs_release_path(path);
3540 key.offset++;
3541 }
3542 ret = 0;
3543
3544 if (last_dest_end < destoff + len) {
3545 /*
3546 * We have an implicit hole (NO_HOLES feature is enabled) that
3547 * fully or partially overlaps our cloning range at its end.
3548 */
3549 btrfs_release_path(path);
3550
3551 /*
3552 * 1 - remove extent(s)
3553 * 1 - inode update
3554 */
3555 trans = btrfs_start_transaction(root, 2);
3556 if (IS_ERR(trans)) {
3557 ret = PTR_ERR(trans);
3558 goto out;
3559 }
3560 ret = btrfs_drop_extents(trans, root, inode,
3561 last_dest_end, destoff + len, 1);
3562 if (ret) {
3563 if (ret != -EOPNOTSUPP)
3564 btrfs_abort_transaction(trans, root, ret);
3565 btrfs_end_transaction(trans, root);
3566 goto out;
3567 }
3568 clone_update_extent_map(inode, trans, NULL, last_dest_end,
3569 destoff + len - last_dest_end);
3570 ret = clone_finish_inode_update(trans, inode, destoff + len,
3571 destoff, olen);
3572 }
3573
3574 out:
3575 btrfs_free_path(path);
3576 vfree(buf);
3577 return ret;
3578 }
3579
3580 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
3581 u64 off, u64 olen, u64 destoff)
3582 {
3583 struct inode *inode = file_inode(file);
3584 struct btrfs_root *root = BTRFS_I(inode)->root;
3585 struct fd src_file;
3586 struct inode *src;
3587 int ret;
3588 u64 len = olen;
3589 u64 bs = root->fs_info->sb->s_blocksize;
3590 int same_inode = 0;
3591
3592 /*
3593 * TODO:
3594 * - split compressed inline extents. annoying: we need to
3595 * decompress into destination's address_space (the file offset
3596 * may change, so source mapping won't do), then recompress (or
3597 * otherwise reinsert) a subrange.
3598 *
3599 * - split destination inode's inline extents. The inline extents can
3600 * be either compressed or non-compressed.
3601 */
3602
3603 /* the destination must be opened for writing */
3604 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
3605 return -EINVAL;
3606
3607 if (btrfs_root_readonly(root))
3608 return -EROFS;
3609
3610 ret = mnt_want_write_file(file);
3611 if (ret)
3612 return ret;
3613
3614 src_file = fdget(srcfd);
3615 if (!src_file.file) {
3616 ret = -EBADF;
3617 goto out_drop_write;
3618 }
3619
3620 ret = -EXDEV;
3621 if (src_file.file->f_path.mnt != file->f_path.mnt)
3622 goto out_fput;
3623
3624 src = file_inode(src_file.file);
3625
3626 ret = -EINVAL;
3627 if (src == inode)
3628 same_inode = 1;
3629
3630 /* the src must be open for reading */
3631 if (!(src_file.file->f_mode & FMODE_READ))
3632 goto out_fput;
3633
3634 /* don't make the dst file partly checksummed */
3635 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3636 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3637 goto out_fput;
3638
3639 ret = -EISDIR;
3640 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3641 goto out_fput;
3642
3643 ret = -EXDEV;
3644 if (src->i_sb != inode->i_sb)
3645 goto out_fput;
3646
3647 if (!same_inode) {
3648 if (inode < src) {
3649 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
3650 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
3651 } else {
3652 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
3653 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
3654 }
3655 } else {
3656 mutex_lock(&src->i_mutex);
3657 }
3658
3659 /* determine range to clone */
3660 ret = -EINVAL;
3661 if (off + len > src->i_size || off + len < off)
3662 goto out_unlock;
3663 if (len == 0)
3664 olen = len = src->i_size - off;
3665 /* if we extend to eof, continue to block boundary */
3666 if (off + len == src->i_size)
3667 len = ALIGN(src->i_size, bs) - off;
3668
3669 /* verify the end result is block aligned */
3670 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
3671 !IS_ALIGNED(destoff, bs))
3672 goto out_unlock;
3673
3674 /* verify if ranges are overlapped within the same file */
3675 if (same_inode) {
3676 if (destoff + len > off && destoff < off + len)
3677 goto out_unlock;
3678 }
3679
3680 if (destoff > inode->i_size) {
3681 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3682 if (ret)
3683 goto out_unlock;
3684 }
3685
3686 /*
3687 * Lock the target range too. Right after we replace the file extent
3688 * items in the fs tree (which now point to the cloned data), we might
3689 * have a worker replace them with extent items relative to a write
3690 * operation that was issued before this clone operation (i.e. confront
3691 * with inode.c:btrfs_finish_ordered_io).
3692 */
3693 if (same_inode) {
3694 u64 lock_start = min_t(u64, off, destoff);
3695 u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
3696
3697 lock_extent_range(src, lock_start, lock_len);
3698 } else {
3699 lock_extent_range(src, off, len);
3700 lock_extent_range(inode, destoff, len);
3701 }
3702
3703 ret = btrfs_clone(src, inode, off, olen, len, destoff);
3704
3705 if (same_inode) {
3706 u64 lock_start = min_t(u64, off, destoff);
3707 u64 lock_end = max_t(u64, off, destoff) + len - 1;
3708
3709 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
3710 } else {
3711 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
3712 unlock_extent(&BTRFS_I(inode)->io_tree, destoff,
3713 destoff + len - 1);
3714 }
3715 /*
3716 * Truncate page cache pages so that future reads will see the cloned
3717 * data immediately and not the previous data.
3718 */
3719 truncate_inode_pages_range(&inode->i_data, destoff,
3720 PAGE_CACHE_ALIGN(destoff + len) - 1);
3721 out_unlock:
3722 if (!same_inode) {
3723 if (inode < src) {
3724 mutex_unlock(&src->i_mutex);
3725 mutex_unlock(&inode->i_mutex);
3726 } else {
3727 mutex_unlock(&inode->i_mutex);
3728 mutex_unlock(&src->i_mutex);
3729 }
3730 } else {
3731 mutex_unlock(&src->i_mutex);
3732 }
3733 out_fput:
3734 fdput(src_file);
3735 out_drop_write:
3736 mnt_drop_write_file(file);
3737 return ret;
3738 }
3739
3740 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3741 {
3742 struct btrfs_ioctl_clone_range_args args;
3743
3744 if (copy_from_user(&args, argp, sizeof(args)))
3745 return -EFAULT;
3746 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
3747 args.src_length, args.dest_offset);
3748 }
3749
3750 /*
3751 * there are many ways the trans_start and trans_end ioctls can lead
3752 * to deadlocks. They should only be used by applications that
3753 * basically own the machine, and have a very in depth understanding
3754 * of all the possible deadlocks and enospc problems.
3755 */
3756 static long btrfs_ioctl_trans_start(struct file *file)
3757 {
3758 struct inode *inode = file_inode(file);
3759 struct btrfs_root *root = BTRFS_I(inode)->root;
3760 struct btrfs_trans_handle *trans;
3761 int ret;
3762
3763 ret = -EPERM;
3764 if (!capable(CAP_SYS_ADMIN))
3765 goto out;
3766
3767 ret = -EINPROGRESS;
3768 if (file->private_data)
3769 goto out;
3770
3771 ret = -EROFS;
3772 if (btrfs_root_readonly(root))
3773 goto out;
3774
3775 ret = mnt_want_write_file(file);
3776 if (ret)
3777 goto out;
3778
3779 atomic_inc(&root->fs_info->open_ioctl_trans);
3780
3781 ret = -ENOMEM;
3782 trans = btrfs_start_ioctl_transaction(root);
3783 if (IS_ERR(trans))
3784 goto out_drop;
3785
3786 file->private_data = trans;
3787 return 0;
3788
3789 out_drop:
3790 atomic_dec(&root->fs_info->open_ioctl_trans);
3791 mnt_drop_write_file(file);
3792 out:
3793 return ret;
3794 }
3795
3796 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3797 {
3798 struct inode *inode = file_inode(file);
3799 struct btrfs_root *root = BTRFS_I(inode)->root;
3800 struct btrfs_root *new_root;
3801 struct btrfs_dir_item *di;
3802 struct btrfs_trans_handle *trans;
3803 struct btrfs_path *path;
3804 struct btrfs_key location;
3805 struct btrfs_disk_key disk_key;
3806 u64 objectid = 0;
3807 u64 dir_id;
3808 int ret;
3809
3810 if (!capable(CAP_SYS_ADMIN))
3811 return -EPERM;
3812
3813 ret = mnt_want_write_file(file);
3814 if (ret)
3815 return ret;
3816
3817 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3818 ret = -EFAULT;
3819 goto out;
3820 }
3821
3822 if (!objectid)
3823 objectid = BTRFS_FS_TREE_OBJECTID;
3824
3825 location.objectid = objectid;
3826 location.type = BTRFS_ROOT_ITEM_KEY;
3827 location.offset = (u64)-1;
3828
3829 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
3830 if (IS_ERR(new_root)) {
3831 ret = PTR_ERR(new_root);
3832 goto out;
3833 }
3834
3835 path = btrfs_alloc_path();
3836 if (!path) {
3837 ret = -ENOMEM;
3838 goto out;
3839 }
3840 path->leave_spinning = 1;
3841
3842 trans = btrfs_start_transaction(root, 1);
3843 if (IS_ERR(trans)) {
3844 btrfs_free_path(path);
3845 ret = PTR_ERR(trans);
3846 goto out;
3847 }
3848
3849 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3850 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
3851 dir_id, "default", 7, 1);
3852 if (IS_ERR_OR_NULL(di)) {
3853 btrfs_free_path(path);
3854 btrfs_end_transaction(trans, root);
3855 btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
3856 "item, this isn't going to work");
3857 ret = -ENOENT;
3858 goto out;
3859 }
3860
3861 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3862 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3863 btrfs_mark_buffer_dirty(path->nodes[0]);
3864 btrfs_free_path(path);
3865
3866 btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
3867 btrfs_end_transaction(trans, root);
3868 out:
3869 mnt_drop_write_file(file);
3870 return ret;
3871 }
3872
3873 void btrfs_get_block_group_info(struct list_head *groups_list,
3874 struct btrfs_ioctl_space_info *space)
3875 {
3876 struct btrfs_block_group_cache *block_group;
3877
3878 space->total_bytes = 0;
3879 space->used_bytes = 0;
3880 space->flags = 0;
3881 list_for_each_entry(block_group, groups_list, list) {
3882 space->flags = block_group->flags;
3883 space->total_bytes += block_group->key.offset;
3884 space->used_bytes +=
3885 btrfs_block_group_used(&block_group->item);
3886 }
3887 }
3888
3889 static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
3890 {
3891 struct btrfs_ioctl_space_args space_args;
3892 struct btrfs_ioctl_space_info space;
3893 struct btrfs_ioctl_space_info *dest;
3894 struct btrfs_ioctl_space_info *dest_orig;
3895 struct btrfs_ioctl_space_info __user *user_dest;
3896 struct btrfs_space_info *info;
3897 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3898 BTRFS_BLOCK_GROUP_SYSTEM,
3899 BTRFS_BLOCK_GROUP_METADATA,
3900 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3901 int num_types = 4;
3902 int alloc_size;
3903 int ret = 0;
3904 u64 slot_count = 0;
3905 int i, c;
3906
3907 if (copy_from_user(&space_args,
3908 (struct btrfs_ioctl_space_args __user *)arg,
3909 sizeof(space_args)))
3910 return -EFAULT;
3911
3912 for (i = 0; i < num_types; i++) {
3913 struct btrfs_space_info *tmp;
3914
3915 info = NULL;
3916 rcu_read_lock();
3917 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3918 list) {
3919 if (tmp->flags == types[i]) {
3920 info = tmp;
3921 break;
3922 }
3923 }
3924 rcu_read_unlock();
3925
3926 if (!info)
3927 continue;
3928
3929 down_read(&info->groups_sem);
3930 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3931 if (!list_empty(&info->block_groups[c]))
3932 slot_count++;
3933 }
3934 up_read(&info->groups_sem);
3935 }
3936
3937 /*
3938 * Global block reserve, exported as a space_info
3939 */
3940 slot_count++;
3941
3942 /* space_slots == 0 means they are asking for a count */
3943 if (space_args.space_slots == 0) {
3944 space_args.total_spaces = slot_count;
3945 goto out;
3946 }
3947
3948 slot_count = min_t(u64, space_args.space_slots, slot_count);
3949
3950 alloc_size = sizeof(*dest) * slot_count;
3951
3952 /* we generally have at most 6 or so space infos, one for each raid
3953 * level. So, a whole page should be more than enough for everyone
3954 */
3955 if (alloc_size > PAGE_CACHE_SIZE)
3956 return -ENOMEM;
3957
3958 space_args.total_spaces = 0;
3959 dest = kmalloc(alloc_size, GFP_NOFS);
3960 if (!dest)
3961 return -ENOMEM;
3962 dest_orig = dest;
3963
3964 /* now we have a buffer to copy into */
3965 for (i = 0; i < num_types; i++) {
3966 struct btrfs_space_info *tmp;
3967
3968 if (!slot_count)
3969 break;
3970
3971 info = NULL;
3972 rcu_read_lock();
3973 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3974 list) {
3975 if (tmp->flags == types[i]) {
3976 info = tmp;
3977 break;
3978 }
3979 }
3980 rcu_read_unlock();
3981
3982 if (!info)
3983 continue;
3984 down_read(&info->groups_sem);
3985 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3986 if (!list_empty(&info->block_groups[c])) {
3987 btrfs_get_block_group_info(
3988 &info->block_groups[c], &space);
3989 memcpy(dest, &space, sizeof(space));
3990 dest++;
3991 space_args.total_spaces++;
3992 slot_count--;
3993 }
3994 if (!slot_count)
3995 break;
3996 }
3997 up_read(&info->groups_sem);
3998 }
3999
4000 /*
4001 * Add global block reserve
4002 */
4003 if (slot_count) {
4004 struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv;
4005
4006 spin_lock(&block_rsv->lock);
4007 space.total_bytes = block_rsv->size;
4008 space.used_bytes = block_rsv->size - block_rsv->reserved;
4009 spin_unlock(&block_rsv->lock);
4010 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
4011 memcpy(dest, &space, sizeof(space));
4012 space_args.total_spaces++;
4013 }
4014
4015 user_dest = (struct btrfs_ioctl_space_info __user *)
4016 (arg + sizeof(struct btrfs_ioctl_space_args));
4017
4018 if (copy_to_user(user_dest, dest_orig, alloc_size))
4019 ret = -EFAULT;
4020
4021 kfree(dest_orig);
4022 out:
4023 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4024 ret = -EFAULT;
4025
4026 return ret;
4027 }
4028
4029 /*
4030 * there are many ways the trans_start and trans_end ioctls can lead
4031 * to deadlocks. They should only be used by applications that
4032 * basically own the machine, and have a very in depth understanding
4033 * of all the possible deadlocks and enospc problems.
4034 */
4035 long btrfs_ioctl_trans_end(struct file *file)
4036 {
4037 struct inode *inode = file_inode(file);
4038 struct btrfs_root *root = BTRFS_I(inode)->root;
4039 struct btrfs_trans_handle *trans;
4040
4041 trans = file->private_data;
4042 if (!trans)
4043 return -EINVAL;
4044 file->private_data = NULL;
4045
4046 btrfs_end_transaction(trans, root);
4047
4048 atomic_dec(&root->fs_info->open_ioctl_trans);
4049
4050 mnt_drop_write_file(file);
4051 return 0;
4052 }
4053
4054 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4055 void __user *argp)
4056 {
4057 struct btrfs_trans_handle *trans;
4058 u64 transid;
4059 int ret;
4060
4061 trans = btrfs_attach_transaction_barrier(root);
4062 if (IS_ERR(trans)) {
4063 if (PTR_ERR(trans) != -ENOENT)
4064 return PTR_ERR(trans);
4065
4066 /* No running transaction, don't bother */
4067 transid = root->fs_info->last_trans_committed;
4068 goto out;
4069 }
4070 transid = trans->transid;
4071 ret = btrfs_commit_transaction_async(trans, root, 0);
4072 if (ret) {
4073 btrfs_end_transaction(trans, root);
4074 return ret;
4075 }
4076 out:
4077 if (argp)
4078 if (copy_to_user(argp, &transid, sizeof(transid)))
4079 return -EFAULT;
4080 return 0;
4081 }
4082
4083 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
4084 void __user *argp)
4085 {
4086 u64 transid;
4087
4088 if (argp) {
4089 if (copy_from_user(&transid, argp, sizeof(transid)))
4090 return -EFAULT;
4091 } else {
4092 transid = 0; /* current trans */
4093 }
4094 return btrfs_wait_for_commit(root, transid);
4095 }
4096
4097 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4098 {
4099 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4100 struct btrfs_ioctl_scrub_args *sa;
4101 int ret;
4102
4103 if (!capable(CAP_SYS_ADMIN))
4104 return -EPERM;
4105
4106 sa = memdup_user(arg, sizeof(*sa));
4107 if (IS_ERR(sa))
4108 return PTR_ERR(sa);
4109
4110 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4111 ret = mnt_want_write_file(file);
4112 if (ret)
4113 goto out;
4114 }
4115
4116 ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
4117 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4118 0);
4119
4120 if (copy_to_user(arg, sa, sizeof(*sa)))
4121 ret = -EFAULT;
4122
4123 if (!(sa->flags & BTRFS_SCRUB_READONLY))
4124 mnt_drop_write_file(file);
4125 out:
4126 kfree(sa);
4127 return ret;
4128 }
4129
4130 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
4131 {
4132 if (!capable(CAP_SYS_ADMIN))
4133 return -EPERM;
4134
4135 return btrfs_scrub_cancel(root->fs_info);
4136 }
4137
4138 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
4139 void __user *arg)
4140 {
4141 struct btrfs_ioctl_scrub_args *sa;
4142 int ret;
4143
4144 if (!capable(CAP_SYS_ADMIN))
4145 return -EPERM;
4146
4147 sa = memdup_user(arg, sizeof(*sa));
4148 if (IS_ERR(sa))
4149 return PTR_ERR(sa);
4150
4151 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
4152
4153 if (copy_to_user(arg, sa, sizeof(*sa)))
4154 ret = -EFAULT;
4155
4156 kfree(sa);
4157 return ret;
4158 }
4159
4160 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
4161 void __user *arg)
4162 {
4163 struct btrfs_ioctl_get_dev_stats *sa;
4164 int ret;
4165
4166 sa = memdup_user(arg, sizeof(*sa));
4167 if (IS_ERR(sa))
4168 return PTR_ERR(sa);
4169
4170 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4171 kfree(sa);
4172 return -EPERM;
4173 }
4174
4175 ret = btrfs_get_dev_stats(root, sa);
4176
4177 if (copy_to_user(arg, sa, sizeof(*sa)))
4178 ret = -EFAULT;
4179
4180 kfree(sa);
4181 return ret;
4182 }
4183
4184 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
4185 {
4186 struct btrfs_ioctl_dev_replace_args *p;
4187 int ret;
4188
4189 if (!capable(CAP_SYS_ADMIN))
4190 return -EPERM;
4191
4192 p = memdup_user(arg, sizeof(*p));
4193 if (IS_ERR(p))
4194 return PTR_ERR(p);
4195
4196 switch (p->cmd) {
4197 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4198 if (root->fs_info->sb->s_flags & MS_RDONLY) {
4199 ret = -EROFS;
4200 goto out;
4201 }
4202 if (atomic_xchg(
4203 &root->fs_info->mutually_exclusive_operation_running,
4204 1)) {
4205 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4206 } else {
4207 ret = btrfs_dev_replace_start(root, p);
4208 atomic_set(
4209 &root->fs_info->mutually_exclusive_operation_running,
4210 0);
4211 }
4212 break;
4213 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4214 btrfs_dev_replace_status(root->fs_info, p);
4215 ret = 0;
4216 break;
4217 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4218 ret = btrfs_dev_replace_cancel(root->fs_info, p);
4219 break;
4220 default:
4221 ret = -EINVAL;
4222 break;
4223 }
4224
4225 if (copy_to_user(arg, p, sizeof(*p)))
4226 ret = -EFAULT;
4227 out:
4228 kfree(p);
4229 return ret;
4230 }
4231
4232 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4233 {
4234 int ret = 0;
4235 int i;
4236 u64 rel_ptr;
4237 int size;
4238 struct btrfs_ioctl_ino_path_args *ipa = NULL;
4239 struct inode_fs_paths *ipath = NULL;
4240 struct btrfs_path *path;
4241
4242 if (!capable(CAP_DAC_READ_SEARCH))
4243 return -EPERM;
4244
4245 path = btrfs_alloc_path();
4246 if (!path) {
4247 ret = -ENOMEM;
4248 goto out;
4249 }
4250
4251 ipa = memdup_user(arg, sizeof(*ipa));
4252 if (IS_ERR(ipa)) {
4253 ret = PTR_ERR(ipa);
4254 ipa = NULL;
4255 goto out;
4256 }
4257
4258 size = min_t(u32, ipa->size, 4096);
4259 ipath = init_ipath(size, root, path);
4260 if (IS_ERR(ipath)) {
4261 ret = PTR_ERR(ipath);
4262 ipath = NULL;
4263 goto out;
4264 }
4265
4266 ret = paths_from_inode(ipa->inum, ipath);
4267 if (ret < 0)
4268 goto out;
4269
4270 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4271 rel_ptr = ipath->fspath->val[i] -
4272 (u64)(unsigned long)ipath->fspath->val;
4273 ipath->fspath->val[i] = rel_ptr;
4274 }
4275
4276 ret = copy_to_user((void *)(unsigned long)ipa->fspath,
4277 (void *)(unsigned long)ipath->fspath, size);
4278 if (ret) {
4279 ret = -EFAULT;
4280 goto out;
4281 }
4282
4283 out:
4284 btrfs_free_path(path);
4285 free_ipath(ipath);
4286 kfree(ipa);
4287
4288 return ret;
4289 }
4290
4291 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4292 {
4293 struct btrfs_data_container *inodes = ctx;
4294 const size_t c = 3 * sizeof(u64);
4295
4296 if (inodes->bytes_left >= c) {
4297 inodes->bytes_left -= c;
4298 inodes->val[inodes->elem_cnt] = inum;
4299 inodes->val[inodes->elem_cnt + 1] = offset;
4300 inodes->val[inodes->elem_cnt + 2] = root;
4301 inodes->elem_cnt += 3;
4302 } else {
4303 inodes->bytes_missing += c - inodes->bytes_left;
4304 inodes->bytes_left = 0;
4305 inodes->elem_missed += 3;
4306 }
4307
4308 return 0;
4309 }
4310
4311 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
4312 void __user *arg)
4313 {
4314 int ret = 0;
4315 int size;
4316 struct btrfs_ioctl_logical_ino_args *loi;
4317 struct btrfs_data_container *inodes = NULL;
4318 struct btrfs_path *path = NULL;
4319
4320 if (!capable(CAP_SYS_ADMIN))
4321 return -EPERM;
4322
4323 loi = memdup_user(arg, sizeof(*loi));
4324 if (IS_ERR(loi)) {
4325 ret = PTR_ERR(loi);
4326 loi = NULL;
4327 goto out;
4328 }
4329
4330 path = btrfs_alloc_path();
4331 if (!path) {
4332 ret = -ENOMEM;
4333 goto out;
4334 }
4335
4336 size = min_t(u32, loi->size, 64 * 1024);
4337 inodes = init_data_container(size);
4338 if (IS_ERR(inodes)) {
4339 ret = PTR_ERR(inodes);
4340 inodes = NULL;
4341 goto out;
4342 }
4343
4344 ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
4345 build_ino_list, inodes);
4346 if (ret == -EINVAL)
4347 ret = -ENOENT;
4348 if (ret < 0)
4349 goto out;
4350
4351 ret = copy_to_user((void *)(unsigned long)loi->inodes,
4352 (void *)(unsigned long)inodes, size);
4353 if (ret)
4354 ret = -EFAULT;
4355
4356 out:
4357 btrfs_free_path(path);
4358 vfree(inodes);
4359 kfree(loi);
4360
4361 return ret;
4362 }
4363
4364 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
4365 struct btrfs_ioctl_balance_args *bargs)
4366 {
4367 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4368
4369 bargs->flags = bctl->flags;
4370
4371 if (atomic_read(&fs_info->balance_running))
4372 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4373 if (atomic_read(&fs_info->balance_pause_req))
4374 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4375 if (atomic_read(&fs_info->balance_cancel_req))
4376 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4377
4378 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4379 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4380 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4381
4382 if (lock) {
4383 spin_lock(&fs_info->balance_lock);
4384 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4385 spin_unlock(&fs_info->balance_lock);
4386 } else {
4387 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4388 }
4389 }
4390
4391 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4392 {
4393 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4394 struct btrfs_fs_info *fs_info = root->fs_info;
4395 struct btrfs_ioctl_balance_args *bargs;
4396 struct btrfs_balance_control *bctl;
4397 bool need_unlock; /* for mut. excl. ops lock */
4398 int ret;
4399
4400 if (!capable(CAP_SYS_ADMIN))
4401 return -EPERM;
4402
4403 ret = mnt_want_write_file(file);
4404 if (ret)
4405 return ret;
4406
4407 again:
4408 if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
4409 mutex_lock(&fs_info->volume_mutex);
4410 mutex_lock(&fs_info->balance_mutex);
4411 need_unlock = true;
4412 goto locked;
4413 }
4414
4415 /*
4416 * mut. excl. ops lock is locked. Three possibilites:
4417 * (1) some other op is running
4418 * (2) balance is running
4419 * (3) balance is paused -- special case (think resume)
4420 */
4421 mutex_lock(&fs_info->balance_mutex);
4422 if (fs_info->balance_ctl) {
4423 /* this is either (2) or (3) */
4424 if (!atomic_read(&fs_info->balance_running)) {
4425 mutex_unlock(&fs_info->balance_mutex);
4426 if (!mutex_trylock(&fs_info->volume_mutex))
4427 goto again;
4428 mutex_lock(&fs_info->balance_mutex);
4429
4430 if (fs_info->balance_ctl &&
4431 !atomic_read(&fs_info->balance_running)) {
4432 /* this is (3) */
4433 need_unlock = false;
4434 goto locked;
4435 }
4436
4437 mutex_unlock(&fs_info->balance_mutex);
4438 mutex_unlock(&fs_info->volume_mutex);
4439 goto again;
4440 } else {
4441 /* this is (2) */
4442 mutex_unlock(&fs_info->balance_mutex);
4443 ret = -EINPROGRESS;
4444 goto out;
4445 }
4446 } else {
4447 /* this is (1) */
4448 mutex_unlock(&fs_info->balance_mutex);
4449 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4450 goto out;
4451 }
4452
4453 locked:
4454 BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4455
4456 if (arg) {
4457 bargs = memdup_user(arg, sizeof(*bargs));
4458 if (IS_ERR(bargs)) {
4459 ret = PTR_ERR(bargs);
4460 goto out_unlock;
4461 }
4462
4463 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4464 if (!fs_info->balance_ctl) {
4465 ret = -ENOTCONN;
4466 goto out_bargs;
4467 }
4468
4469 bctl = fs_info->balance_ctl;
4470 spin_lock(&fs_info->balance_lock);
4471 bctl->flags |= BTRFS_BALANCE_RESUME;
4472 spin_unlock(&fs_info->balance_lock);
4473
4474 goto do_balance;
4475 }
4476 } else {
4477 bargs = NULL;
4478 }
4479
4480 if (fs_info->balance_ctl) {
4481 ret = -EINPROGRESS;
4482 goto out_bargs;
4483 }
4484
4485 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
4486 if (!bctl) {
4487 ret = -ENOMEM;
4488 goto out_bargs;
4489 }
4490
4491 bctl->fs_info = fs_info;
4492 if (arg) {
4493 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4494 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4495 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4496
4497 bctl->flags = bargs->flags;
4498 } else {
4499 /* balance everything - no filters */
4500 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4501 }
4502
4503 do_balance:
4504 /*
4505 * Ownership of bctl and mutually_exclusive_operation_running
4506 * goes to to btrfs_balance. bctl is freed in __cancel_balance,
4507 * or, if restriper was paused all the way until unmount, in
4508 * free_fs_info. mutually_exclusive_operation_running is
4509 * cleared in __cancel_balance.
4510 */
4511 need_unlock = false;
4512
4513 ret = btrfs_balance(bctl, bargs);
4514
4515 if (arg) {
4516 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4517 ret = -EFAULT;
4518 }
4519
4520 out_bargs:
4521 kfree(bargs);
4522 out_unlock:
4523 mutex_unlock(&fs_info->balance_mutex);
4524 mutex_unlock(&fs_info->volume_mutex);
4525 if (need_unlock)
4526 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
4527 out:
4528 mnt_drop_write_file(file);
4529 return ret;
4530 }
4531
4532 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
4533 {
4534 if (!capable(CAP_SYS_ADMIN))
4535 return -EPERM;
4536
4537 switch (cmd) {
4538 case BTRFS_BALANCE_CTL_PAUSE:
4539 return btrfs_pause_balance(root->fs_info);
4540 case BTRFS_BALANCE_CTL_CANCEL:
4541 return btrfs_cancel_balance(root->fs_info);
4542 }
4543
4544 return -EINVAL;
4545 }
4546
4547 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
4548 void __user *arg)
4549 {
4550 struct btrfs_fs_info *fs_info = root->fs_info;
4551 struct btrfs_ioctl_balance_args *bargs;
4552 int ret = 0;
4553
4554 if (!capable(CAP_SYS_ADMIN))
4555 return -EPERM;
4556
4557 mutex_lock(&fs_info->balance_mutex);
4558 if (!fs_info->balance_ctl) {
4559 ret = -ENOTCONN;
4560 goto out;
4561 }
4562
4563 bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
4564 if (!bargs) {
4565 ret = -ENOMEM;
4566 goto out;
4567 }
4568
4569 update_ioctl_balance_args(fs_info, 1, bargs);
4570
4571 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4572 ret = -EFAULT;
4573
4574 kfree(bargs);
4575 out:
4576 mutex_unlock(&fs_info->balance_mutex);
4577 return ret;
4578 }
4579
4580 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4581 {
4582 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4583 struct btrfs_ioctl_quota_ctl_args *sa;
4584 struct btrfs_trans_handle *trans = NULL;
4585 int ret;
4586 int err;
4587
4588 if (!capable(CAP_SYS_ADMIN))
4589 return -EPERM;
4590
4591 ret = mnt_want_write_file(file);
4592 if (ret)
4593 return ret;
4594
4595 sa = memdup_user(arg, sizeof(*sa));
4596 if (IS_ERR(sa)) {
4597 ret = PTR_ERR(sa);
4598 goto drop_write;
4599 }
4600
4601 down_write(&root->fs_info->subvol_sem);
4602 trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
4603 if (IS_ERR(trans)) {
4604 ret = PTR_ERR(trans);
4605 goto out;
4606 }
4607
4608 switch (sa->cmd) {
4609 case BTRFS_QUOTA_CTL_ENABLE:
4610 ret = btrfs_quota_enable(trans, root->fs_info);
4611 break;
4612 case BTRFS_QUOTA_CTL_DISABLE:
4613 ret = btrfs_quota_disable(trans, root->fs_info);
4614 break;
4615 default:
4616 ret = -EINVAL;
4617 break;
4618 }
4619
4620 err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
4621 if (err && !ret)
4622 ret = err;
4623 out:
4624 kfree(sa);
4625 up_write(&root->fs_info->subvol_sem);
4626 drop_write:
4627 mnt_drop_write_file(file);
4628 return ret;
4629 }
4630
4631 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4632 {
4633 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4634 struct btrfs_ioctl_qgroup_assign_args *sa;
4635 struct btrfs_trans_handle *trans;
4636 int ret;
4637 int err;
4638
4639 if (!capable(CAP_SYS_ADMIN))
4640 return -EPERM;
4641
4642 ret = mnt_want_write_file(file);
4643 if (ret)
4644 return ret;
4645
4646 sa = memdup_user(arg, sizeof(*sa));
4647 if (IS_ERR(sa)) {
4648 ret = PTR_ERR(sa);
4649 goto drop_write;
4650 }
4651
4652 trans = btrfs_join_transaction(root);
4653 if (IS_ERR(trans)) {
4654 ret = PTR_ERR(trans);
4655 goto out;
4656 }
4657
4658 /* FIXME: check if the IDs really exist */
4659 if (sa->assign) {
4660 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
4661 sa->src, sa->dst);
4662 } else {
4663 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
4664 sa->src, sa->dst);
4665 }
4666
4667 err = btrfs_end_transaction(trans, root);
4668 if (err && !ret)
4669 ret = err;
4670
4671 out:
4672 kfree(sa);
4673 drop_write:
4674 mnt_drop_write_file(file);
4675 return ret;
4676 }
4677
4678 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4679 {
4680 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4681 struct btrfs_ioctl_qgroup_create_args *sa;
4682 struct btrfs_trans_handle *trans;
4683 int ret;
4684 int err;
4685
4686 if (!capable(CAP_SYS_ADMIN))
4687 return -EPERM;
4688
4689 ret = mnt_want_write_file(file);
4690 if (ret)
4691 return ret;
4692
4693 sa = memdup_user(arg, sizeof(*sa));
4694 if (IS_ERR(sa)) {
4695 ret = PTR_ERR(sa);
4696 goto drop_write;
4697 }
4698
4699 if (!sa->qgroupid) {
4700 ret = -EINVAL;
4701 goto out;
4702 }
4703
4704 trans = btrfs_join_transaction(root);
4705 if (IS_ERR(trans)) {
4706 ret = PTR_ERR(trans);
4707 goto out;
4708 }
4709
4710 /* FIXME: check if the IDs really exist */
4711 if (sa->create) {
4712 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
4713 NULL);
4714 } else {
4715 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
4716 }
4717
4718 err = btrfs_end_transaction(trans, root);
4719 if (err && !ret)
4720 ret = err;
4721
4722 out:
4723 kfree(sa);
4724 drop_write:
4725 mnt_drop_write_file(file);
4726 return ret;
4727 }
4728
4729 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4730 {
4731 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4732 struct btrfs_ioctl_qgroup_limit_args *sa;
4733 struct btrfs_trans_handle *trans;
4734 int ret;
4735 int err;
4736 u64 qgroupid;
4737
4738 if (!capable(CAP_SYS_ADMIN))
4739 return -EPERM;
4740
4741 ret = mnt_want_write_file(file);
4742 if (ret)
4743 return ret;
4744
4745 sa = memdup_user(arg, sizeof(*sa));
4746 if (IS_ERR(sa)) {
4747 ret = PTR_ERR(sa);
4748 goto drop_write;
4749 }
4750
4751 trans = btrfs_join_transaction(root);
4752 if (IS_ERR(trans)) {
4753 ret = PTR_ERR(trans);
4754 goto out;
4755 }
4756
4757 qgroupid = sa->qgroupid;
4758 if (!qgroupid) {
4759 /* take the current subvol as qgroup */
4760 qgroupid = root->root_key.objectid;
4761 }
4762
4763 /* FIXME: check if the IDs really exist */
4764 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
4765
4766 err = btrfs_end_transaction(trans, root);
4767 if (err && !ret)
4768 ret = err;
4769
4770 out:
4771 kfree(sa);
4772 drop_write:
4773 mnt_drop_write_file(file);
4774 return ret;
4775 }
4776
4777 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4778 {
4779 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4780 struct btrfs_ioctl_quota_rescan_args *qsa;
4781 int ret;
4782
4783 if (!capable(CAP_SYS_ADMIN))
4784 return -EPERM;
4785
4786 ret = mnt_want_write_file(file);
4787 if (ret)
4788 return ret;
4789
4790 qsa = memdup_user(arg, sizeof(*qsa));
4791 if (IS_ERR(qsa)) {
4792 ret = PTR_ERR(qsa);
4793 goto drop_write;
4794 }
4795
4796 if (qsa->flags) {
4797 ret = -EINVAL;
4798 goto out;
4799 }
4800
4801 ret = btrfs_qgroup_rescan(root->fs_info);
4802
4803 out:
4804 kfree(qsa);
4805 drop_write:
4806 mnt_drop_write_file(file);
4807 return ret;
4808 }
4809
4810 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
4811 {
4812 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4813 struct btrfs_ioctl_quota_rescan_args *qsa;
4814 int ret = 0;
4815
4816 if (!capable(CAP_SYS_ADMIN))
4817 return -EPERM;
4818
4819 qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
4820 if (!qsa)
4821 return -ENOMEM;
4822
4823 if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4824 qsa->flags = 1;
4825 qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
4826 }
4827
4828 if (copy_to_user(arg, qsa, sizeof(*qsa)))
4829 ret = -EFAULT;
4830
4831 kfree(qsa);
4832 return ret;
4833 }
4834
4835 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
4836 {
4837 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4838
4839 if (!capable(CAP_SYS_ADMIN))
4840 return -EPERM;
4841
4842 return btrfs_qgroup_wait_for_completion(root->fs_info);
4843 }
4844
4845 static long _btrfs_ioctl_set_received_subvol(struct file *file,
4846 struct btrfs_ioctl_received_subvol_args *sa)
4847 {
4848 struct inode *inode = file_inode(file);
4849 struct btrfs_root *root = BTRFS_I(inode)->root;
4850 struct btrfs_root_item *root_item = &root->root_item;
4851 struct btrfs_trans_handle *trans;
4852 struct timespec ct = CURRENT_TIME;
4853 int ret = 0;
4854 int received_uuid_changed;
4855
4856 if (!inode_owner_or_capable(inode))
4857 return -EPERM;
4858
4859 ret = mnt_want_write_file(file);
4860 if (ret < 0)
4861 return ret;
4862
4863 down_write(&root->fs_info->subvol_sem);
4864
4865 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
4866 ret = -EINVAL;
4867 goto out;
4868 }
4869
4870 if (btrfs_root_readonly(root)) {
4871 ret = -EROFS;
4872 goto out;
4873 }
4874
4875 /*
4876 * 1 - root item
4877 * 2 - uuid items (received uuid + subvol uuid)
4878 */
4879 trans = btrfs_start_transaction(root, 3);
4880 if (IS_ERR(trans)) {
4881 ret = PTR_ERR(trans);
4882 trans = NULL;
4883 goto out;
4884 }
4885
4886 sa->rtransid = trans->transid;
4887 sa->rtime.sec = ct.tv_sec;
4888 sa->rtime.nsec = ct.tv_nsec;
4889
4890 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4891 BTRFS_UUID_SIZE);
4892 if (received_uuid_changed &&
4893 !btrfs_is_empty_uuid(root_item->received_uuid))
4894 btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
4895 root_item->received_uuid,
4896 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4897 root->root_key.objectid);
4898 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4899 btrfs_set_root_stransid(root_item, sa->stransid);
4900 btrfs_set_root_rtransid(root_item, sa->rtransid);
4901 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4902 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4903 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4904 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4905
4906 ret = btrfs_update_root(trans, root->fs_info->tree_root,
4907 &root->root_key, &root->root_item);
4908 if (ret < 0) {
4909 btrfs_end_transaction(trans, root);
4910 goto out;
4911 }
4912 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4913 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
4914 sa->uuid,
4915 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4916 root->root_key.objectid);
4917 if (ret < 0 && ret != -EEXIST) {
4918 btrfs_abort_transaction(trans, root, ret);
4919 goto out;
4920 }
4921 }
4922 ret = btrfs_commit_transaction(trans, root);
4923 if (ret < 0) {
4924 btrfs_abort_transaction(trans, root, ret);
4925 goto out;
4926 }
4927
4928 out:
4929 up_write(&root->fs_info->subvol_sem);
4930 mnt_drop_write_file(file);
4931 return ret;
4932 }
4933
4934 #ifdef CONFIG_64BIT
4935 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4936 void __user *arg)
4937 {
4938 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4939 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4940 int ret = 0;
4941
4942 args32 = memdup_user(arg, sizeof(*args32));
4943 if (IS_ERR(args32)) {
4944 ret = PTR_ERR(args32);
4945 args32 = NULL;
4946 goto out;
4947 }
4948
4949 args64 = kmalloc(sizeof(*args64), GFP_NOFS);
4950 if (!args64) {
4951 ret = -ENOMEM;
4952 goto out;
4953 }
4954
4955 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4956 args64->stransid = args32->stransid;
4957 args64->rtransid = args32->rtransid;
4958 args64->stime.sec = args32->stime.sec;
4959 args64->stime.nsec = args32->stime.nsec;
4960 args64->rtime.sec = args32->rtime.sec;
4961 args64->rtime.nsec = args32->rtime.nsec;
4962 args64->flags = args32->flags;
4963
4964 ret = _btrfs_ioctl_set_received_subvol(file, args64);
4965 if (ret)
4966 goto out;
4967
4968 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4969 args32->stransid = args64->stransid;
4970 args32->rtransid = args64->rtransid;
4971 args32->stime.sec = args64->stime.sec;
4972 args32->stime.nsec = args64->stime.nsec;
4973 args32->rtime.sec = args64->rtime.sec;
4974 args32->rtime.nsec = args64->rtime.nsec;
4975 args32->flags = args64->flags;
4976
4977 ret = copy_to_user(arg, args32, sizeof(*args32));
4978 if (ret)
4979 ret = -EFAULT;
4980
4981 out:
4982 kfree(args32);
4983 kfree(args64);
4984 return ret;
4985 }
4986 #endif
4987
4988 static long btrfs_ioctl_set_received_subvol(struct file *file,
4989 void __user *arg)
4990 {
4991 struct btrfs_ioctl_received_subvol_args *sa = NULL;
4992 int ret = 0;
4993
4994 sa = memdup_user(arg, sizeof(*sa));
4995 if (IS_ERR(sa)) {
4996 ret = PTR_ERR(sa);
4997 sa = NULL;
4998 goto out;
4999 }
5000
5001 ret = _btrfs_ioctl_set_received_subvol(file, sa);
5002
5003 if (ret)
5004 goto out;
5005
5006 ret = copy_to_user(arg, sa, sizeof(*sa));
5007 if (ret)
5008 ret = -EFAULT;
5009
5010 out:
5011 kfree(sa);
5012 return ret;
5013 }
5014
5015 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
5016 {
5017 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5018 size_t len;
5019 int ret;
5020 char label[BTRFS_LABEL_SIZE];
5021
5022 spin_lock(&root->fs_info->super_lock);
5023 memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5024 spin_unlock(&root->fs_info->super_lock);
5025
5026 len = strnlen(label, BTRFS_LABEL_SIZE);
5027
5028 if (len == BTRFS_LABEL_SIZE) {
5029 btrfs_warn(root->fs_info,
5030 "label is too long, return the first %zu bytes", --len);
5031 }
5032
5033 ret = copy_to_user(arg, label, len);
5034
5035 return ret ? -EFAULT : 0;
5036 }
5037
5038 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5039 {
5040 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5041 struct btrfs_super_block *super_block = root->fs_info->super_copy;
5042 struct btrfs_trans_handle *trans;
5043 char label[BTRFS_LABEL_SIZE];
5044 int ret;
5045
5046 if (!capable(CAP_SYS_ADMIN))
5047 return -EPERM;
5048
5049 if (copy_from_user(label, arg, sizeof(label)))
5050 return -EFAULT;
5051
5052 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5053 btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
5054 BTRFS_LABEL_SIZE - 1);
5055 return -EINVAL;
5056 }
5057
5058 ret = mnt_want_write_file(file);
5059 if (ret)
5060 return ret;
5061
5062 trans = btrfs_start_transaction(root, 0);
5063 if (IS_ERR(trans)) {
5064 ret = PTR_ERR(trans);
5065 goto out_unlock;
5066 }
5067
5068 spin_lock(&root->fs_info->super_lock);
5069 strcpy(super_block->label, label);
5070 spin_unlock(&root->fs_info->super_lock);
5071 ret = btrfs_commit_transaction(trans, root);
5072
5073 out_unlock:
5074 mnt_drop_write_file(file);
5075 return ret;
5076 }
5077
5078 #define INIT_FEATURE_FLAGS(suffix) \
5079 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5080 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5081 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5082
5083 static int btrfs_ioctl_get_supported_features(struct file *file,
5084 void __user *arg)
5085 {
5086 static struct btrfs_ioctl_feature_flags features[3] = {
5087 INIT_FEATURE_FLAGS(SUPP),
5088 INIT_FEATURE_FLAGS(SAFE_SET),
5089 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5090 };
5091
5092 if (copy_to_user(arg, &features, sizeof(features)))
5093 return -EFAULT;
5094
5095 return 0;
5096 }
5097
5098 static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5099 {
5100 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5101 struct btrfs_super_block *super_block = root->fs_info->super_copy;
5102 struct btrfs_ioctl_feature_flags features;
5103
5104 features.compat_flags = btrfs_super_compat_flags(super_block);
5105 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5106 features.incompat_flags = btrfs_super_incompat_flags(super_block);
5107
5108 if (copy_to_user(arg, &features, sizeof(features)))
5109 return -EFAULT;
5110
5111 return 0;
5112 }
5113
5114 static int check_feature_bits(struct btrfs_root *root,
5115 enum btrfs_feature_set set,
5116 u64 change_mask, u64 flags, u64 supported_flags,
5117 u64 safe_set, u64 safe_clear)
5118 {
5119 const char *type = btrfs_feature_set_names[set];
5120 char *names;
5121 u64 disallowed, unsupported;
5122 u64 set_mask = flags & change_mask;
5123 u64 clear_mask = ~flags & change_mask;
5124
5125 unsupported = set_mask & ~supported_flags;
5126 if (unsupported) {
5127 names = btrfs_printable_features(set, unsupported);
5128 if (names) {
5129 btrfs_warn(root->fs_info,
5130 "this kernel does not support the %s feature bit%s",
5131 names, strchr(names, ',') ? "s" : "");
5132 kfree(names);
5133 } else
5134 btrfs_warn(root->fs_info,
5135 "this kernel does not support %s bits 0x%llx",
5136 type, unsupported);
5137 return -EOPNOTSUPP;
5138 }
5139
5140 disallowed = set_mask & ~safe_set;
5141 if (disallowed) {
5142 names = btrfs_printable_features(set, disallowed);
5143 if (names) {
5144 btrfs_warn(root->fs_info,
5145 "can't set the %s feature bit%s while mounted",
5146 names, strchr(names, ',') ? "s" : "");
5147 kfree(names);
5148 } else
5149 btrfs_warn(root->fs_info,
5150 "can't set %s bits 0x%llx while mounted",
5151 type, disallowed);
5152 return -EPERM;
5153 }
5154
5155 disallowed = clear_mask & ~safe_clear;
5156 if (disallowed) {
5157 names = btrfs_printable_features(set, disallowed);
5158 if (names) {
5159 btrfs_warn(root->fs_info,
5160 "can't clear the %s feature bit%s while mounted",
5161 names, strchr(names, ',') ? "s" : "");
5162 kfree(names);
5163 } else
5164 btrfs_warn(root->fs_info,
5165 "can't clear %s bits 0x%llx while mounted",
5166 type, disallowed);
5167 return -EPERM;
5168 }
5169
5170 return 0;
5171 }
5172
5173 #define check_feature(root, change_mask, flags, mask_base) \
5174 check_feature_bits(root, FEAT_##mask_base, change_mask, flags, \
5175 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
5176 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
5177 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5178
5179 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5180 {
5181 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5182 struct btrfs_super_block *super_block = root->fs_info->super_copy;
5183 struct btrfs_ioctl_feature_flags flags[2];
5184 struct btrfs_trans_handle *trans;
5185 u64 newflags;
5186 int ret;
5187
5188 if (!capable(CAP_SYS_ADMIN))
5189 return -EPERM;
5190
5191 if (copy_from_user(flags, arg, sizeof(flags)))
5192 return -EFAULT;
5193
5194 /* Nothing to do */
5195 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5196 !flags[0].incompat_flags)
5197 return 0;
5198
5199 ret = check_feature(root, flags[0].compat_flags,
5200 flags[1].compat_flags, COMPAT);
5201 if (ret)
5202 return ret;
5203
5204 ret = check_feature(root, flags[0].compat_ro_flags,
5205 flags[1].compat_ro_flags, COMPAT_RO);
5206 if (ret)
5207 return ret;
5208
5209 ret = check_feature(root, flags[0].incompat_flags,
5210 flags[1].incompat_flags, INCOMPAT);
5211 if (ret)
5212 return ret;
5213
5214 trans = btrfs_start_transaction(root, 0);
5215 if (IS_ERR(trans))
5216 return PTR_ERR(trans);
5217
5218 spin_lock(&root->fs_info->super_lock);
5219 newflags = btrfs_super_compat_flags(super_block);
5220 newflags |= flags[0].compat_flags & flags[1].compat_flags;
5221 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5222 btrfs_set_super_compat_flags(super_block, newflags);
5223
5224 newflags = btrfs_super_compat_ro_flags(super_block);
5225 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5226 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5227 btrfs_set_super_compat_ro_flags(super_block, newflags);
5228
5229 newflags = btrfs_super_incompat_flags(super_block);
5230 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5231 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5232 btrfs_set_super_incompat_flags(super_block, newflags);
5233 spin_unlock(&root->fs_info->super_lock);
5234
5235 return btrfs_commit_transaction(trans, root);
5236 }
5237
5238 long btrfs_ioctl(struct file *file, unsigned int
5239 cmd, unsigned long arg)
5240 {
5241 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5242 void __user *argp = (void __user *)arg;
5243
5244 switch (cmd) {
5245 case FS_IOC_GETFLAGS:
5246 return btrfs_ioctl_getflags(file, argp);
5247 case FS_IOC_SETFLAGS:
5248 return btrfs_ioctl_setflags(file, argp);
5249 case FS_IOC_GETVERSION:
5250 return btrfs_ioctl_getversion(file, argp);
5251 case FITRIM:
5252 return btrfs_ioctl_fitrim(file, argp);
5253 case BTRFS_IOC_SNAP_CREATE:
5254 return btrfs_ioctl_snap_create(file, argp, 0);
5255 case BTRFS_IOC_SNAP_CREATE_V2:
5256 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5257 case BTRFS_IOC_SUBVOL_CREATE:
5258 return btrfs_ioctl_snap_create(file, argp, 1);
5259 case BTRFS_IOC_SUBVOL_CREATE_V2:
5260 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5261 case BTRFS_IOC_SNAP_DESTROY:
5262 return btrfs_ioctl_snap_destroy(file, argp);
5263 case BTRFS_IOC_SUBVOL_GETFLAGS:
5264 return btrfs_ioctl_subvol_getflags(file, argp);
5265 case BTRFS_IOC_SUBVOL_SETFLAGS:
5266 return btrfs_ioctl_subvol_setflags(file, argp);
5267 case BTRFS_IOC_DEFAULT_SUBVOL:
5268 return btrfs_ioctl_default_subvol(file, argp);
5269 case BTRFS_IOC_DEFRAG:
5270 return btrfs_ioctl_defrag(file, NULL);
5271 case BTRFS_IOC_DEFRAG_RANGE:
5272 return btrfs_ioctl_defrag(file, argp);
5273 case BTRFS_IOC_RESIZE:
5274 return btrfs_ioctl_resize(file, argp);
5275 case BTRFS_IOC_ADD_DEV:
5276 return btrfs_ioctl_add_dev(root, argp);
5277 case BTRFS_IOC_RM_DEV:
5278 return btrfs_ioctl_rm_dev(file, argp);
5279 case BTRFS_IOC_FS_INFO:
5280 return btrfs_ioctl_fs_info(root, argp);
5281 case BTRFS_IOC_DEV_INFO:
5282 return btrfs_ioctl_dev_info(root, argp);
5283 case BTRFS_IOC_BALANCE:
5284 return btrfs_ioctl_balance(file, NULL);
5285 case BTRFS_IOC_CLONE:
5286 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
5287 case BTRFS_IOC_CLONE_RANGE:
5288 return btrfs_ioctl_clone_range(file, argp);
5289 case BTRFS_IOC_TRANS_START:
5290 return btrfs_ioctl_trans_start(file);
5291 case BTRFS_IOC_TRANS_END:
5292 return btrfs_ioctl_trans_end(file);
5293 case BTRFS_IOC_TREE_SEARCH:
5294 return btrfs_ioctl_tree_search(file, argp);
5295 case BTRFS_IOC_TREE_SEARCH_V2:
5296 return btrfs_ioctl_tree_search_v2(file, argp);
5297 case BTRFS_IOC_INO_LOOKUP:
5298 return btrfs_ioctl_ino_lookup(file, argp);
5299 case BTRFS_IOC_INO_PATHS:
5300 return btrfs_ioctl_ino_to_path(root, argp);
5301 case BTRFS_IOC_LOGICAL_INO:
5302 return btrfs_ioctl_logical_to_ino(root, argp);
5303 case BTRFS_IOC_SPACE_INFO:
5304 return btrfs_ioctl_space_info(root, argp);
5305 case BTRFS_IOC_SYNC: {
5306 int ret;
5307
5308 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
5309 if (ret)
5310 return ret;
5311 ret = btrfs_sync_fs(file->f_dentry->d_sb, 1);
5312 return ret;
5313 }
5314 case BTRFS_IOC_START_SYNC:
5315 return btrfs_ioctl_start_sync(root, argp);
5316 case BTRFS_IOC_WAIT_SYNC:
5317 return btrfs_ioctl_wait_sync(root, argp);
5318 case BTRFS_IOC_SCRUB:
5319 return btrfs_ioctl_scrub(file, argp);
5320 case BTRFS_IOC_SCRUB_CANCEL:
5321 return btrfs_ioctl_scrub_cancel(root, argp);
5322 case BTRFS_IOC_SCRUB_PROGRESS:
5323 return btrfs_ioctl_scrub_progress(root, argp);
5324 case BTRFS_IOC_BALANCE_V2:
5325 return btrfs_ioctl_balance(file, argp);
5326 case BTRFS_IOC_BALANCE_CTL:
5327 return btrfs_ioctl_balance_ctl(root, arg);
5328 case BTRFS_IOC_BALANCE_PROGRESS:
5329 return btrfs_ioctl_balance_progress(root, argp);
5330 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5331 return btrfs_ioctl_set_received_subvol(file, argp);
5332 #ifdef CONFIG_64BIT
5333 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5334 return btrfs_ioctl_set_received_subvol_32(file, argp);
5335 #endif
5336 case BTRFS_IOC_SEND:
5337 return btrfs_ioctl_send(file, argp);
5338 case BTRFS_IOC_GET_DEV_STATS:
5339 return btrfs_ioctl_get_dev_stats(root, argp);
5340 case BTRFS_IOC_QUOTA_CTL:
5341 return btrfs_ioctl_quota_ctl(file, argp);
5342 case BTRFS_IOC_QGROUP_ASSIGN:
5343 return btrfs_ioctl_qgroup_assign(file, argp);
5344 case BTRFS_IOC_QGROUP_CREATE:
5345 return btrfs_ioctl_qgroup_create(file, argp);
5346 case BTRFS_IOC_QGROUP_LIMIT:
5347 return btrfs_ioctl_qgroup_limit(file, argp);
5348 case BTRFS_IOC_QUOTA_RESCAN:
5349 return btrfs_ioctl_quota_rescan(file, argp);
5350 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5351 return btrfs_ioctl_quota_rescan_status(file, argp);
5352 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5353 return btrfs_ioctl_quota_rescan_wait(file, argp);
5354 case BTRFS_IOC_DEV_REPLACE:
5355 return btrfs_ioctl_dev_replace(root, argp);
5356 case BTRFS_IOC_GET_FSLABEL:
5357 return btrfs_ioctl_get_fslabel(file, argp);
5358 case BTRFS_IOC_SET_FSLABEL:
5359 return btrfs_ioctl_set_fslabel(file, argp);
5360 case BTRFS_IOC_FILE_EXTENT_SAME:
5361 return btrfs_ioctl_file_extent_same(file, argp);
5362 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5363 return btrfs_ioctl_get_supported_features(file, argp);
5364 case BTRFS_IOC_GET_FEATURES:
5365 return btrfs_ioctl_get_features(file, argp);
5366 case BTRFS_IOC_SET_FEATURES:
5367 return btrfs_ioctl_set_features(file, argp);
5368 }
5369
5370 return -ENOTTY;
5371 }
Linux kernel - Deliverables
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