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