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Btrfs: fix cleaner thread not working with inode cache option
[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 "compat.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 /* Mask out flags that are inappropriate for the given type of inode. */
61 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
62 {
63 if (S_ISDIR(mode))
64 return flags;
65 else if (S_ISREG(mode))
66 return flags & ~FS_DIRSYNC_FL;
67 else
68 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
69 }
70
71 /*
72 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
73 */
74 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
75 {
76 unsigned int iflags = 0;
77
78 if (flags & BTRFS_INODE_SYNC)
79 iflags |= FS_SYNC_FL;
80 if (flags & BTRFS_INODE_IMMUTABLE)
81 iflags |= FS_IMMUTABLE_FL;
82 if (flags & BTRFS_INODE_APPEND)
83 iflags |= FS_APPEND_FL;
84 if (flags & BTRFS_INODE_NODUMP)
85 iflags |= FS_NODUMP_FL;
86 if (flags & BTRFS_INODE_NOATIME)
87 iflags |= FS_NOATIME_FL;
88 if (flags & BTRFS_INODE_DIRSYNC)
89 iflags |= FS_DIRSYNC_FL;
90 if (flags & BTRFS_INODE_NODATACOW)
91 iflags |= FS_NOCOW_FL;
92
93 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
94 iflags |= FS_COMPR_FL;
95 else if (flags & BTRFS_INODE_NOCOMPRESS)
96 iflags |= FS_NOCOMP_FL;
97
98 return iflags;
99 }
100
101 /*
102 * Update inode->i_flags based on the btrfs internal flags.
103 */
104 void btrfs_update_iflags(struct inode *inode)
105 {
106 struct btrfs_inode *ip = BTRFS_I(inode);
107
108 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
109
110 if (ip->flags & BTRFS_INODE_SYNC)
111 inode->i_flags |= S_SYNC;
112 if (ip->flags & BTRFS_INODE_IMMUTABLE)
113 inode->i_flags |= S_IMMUTABLE;
114 if (ip->flags & BTRFS_INODE_APPEND)
115 inode->i_flags |= S_APPEND;
116 if (ip->flags & BTRFS_INODE_NOATIME)
117 inode->i_flags |= S_NOATIME;
118 if (ip->flags & BTRFS_INODE_DIRSYNC)
119 inode->i_flags |= S_DIRSYNC;
120 }
121
122 /*
123 * Inherit flags from the parent inode.
124 *
125 * Currently only the compression flags and the cow flags are inherited.
126 */
127 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
128 {
129 unsigned int flags;
130
131 if (!dir)
132 return;
133
134 flags = BTRFS_I(dir)->flags;
135
136 if (flags & BTRFS_INODE_NOCOMPRESS) {
137 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
138 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
139 } else if (flags & BTRFS_INODE_COMPRESS) {
140 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
141 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
142 }
143
144 if (flags & BTRFS_INODE_NODATACOW) {
145 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
146 if (S_ISREG(inode->i_mode))
147 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
148 }
149
150 btrfs_update_iflags(inode);
151 }
152
153 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
154 {
155 struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
156 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
157
158 if (copy_to_user(arg, &flags, sizeof(flags)))
159 return -EFAULT;
160 return 0;
161 }
162
163 static int check_flags(unsigned int flags)
164 {
165 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
166 FS_NOATIME_FL | FS_NODUMP_FL | \
167 FS_SYNC_FL | FS_DIRSYNC_FL | \
168 FS_NOCOMP_FL | FS_COMPR_FL |
169 FS_NOCOW_FL))
170 return -EOPNOTSUPP;
171
172 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
173 return -EINVAL;
174
175 return 0;
176 }
177
178 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
179 {
180 struct inode *inode = file->f_path.dentry->d_inode;
181 struct btrfs_inode *ip = BTRFS_I(inode);
182 struct btrfs_root *root = ip->root;
183 struct btrfs_trans_handle *trans;
184 unsigned int flags, oldflags;
185 int ret;
186 u64 ip_oldflags;
187 unsigned int i_oldflags;
188 umode_t mode;
189
190 if (btrfs_root_readonly(root))
191 return -EROFS;
192
193 if (copy_from_user(&flags, arg, sizeof(flags)))
194 return -EFAULT;
195
196 ret = check_flags(flags);
197 if (ret)
198 return ret;
199
200 if (!inode_owner_or_capable(inode))
201 return -EACCES;
202
203 ret = mnt_want_write_file(file);
204 if (ret)
205 return ret;
206
207 mutex_lock(&inode->i_mutex);
208
209 ip_oldflags = ip->flags;
210 i_oldflags = inode->i_flags;
211 mode = inode->i_mode;
212
213 flags = btrfs_mask_flags(inode->i_mode, flags);
214 oldflags = btrfs_flags_to_ioctl(ip->flags);
215 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
216 if (!capable(CAP_LINUX_IMMUTABLE)) {
217 ret = -EPERM;
218 goto out_unlock;
219 }
220 }
221
222 if (flags & FS_SYNC_FL)
223 ip->flags |= BTRFS_INODE_SYNC;
224 else
225 ip->flags &= ~BTRFS_INODE_SYNC;
226 if (flags & FS_IMMUTABLE_FL)
227 ip->flags |= BTRFS_INODE_IMMUTABLE;
228 else
229 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
230 if (flags & FS_APPEND_FL)
231 ip->flags |= BTRFS_INODE_APPEND;
232 else
233 ip->flags &= ~BTRFS_INODE_APPEND;
234 if (flags & FS_NODUMP_FL)
235 ip->flags |= BTRFS_INODE_NODUMP;
236 else
237 ip->flags &= ~BTRFS_INODE_NODUMP;
238 if (flags & FS_NOATIME_FL)
239 ip->flags |= BTRFS_INODE_NOATIME;
240 else
241 ip->flags &= ~BTRFS_INODE_NOATIME;
242 if (flags & FS_DIRSYNC_FL)
243 ip->flags |= BTRFS_INODE_DIRSYNC;
244 else
245 ip->flags &= ~BTRFS_INODE_DIRSYNC;
246 if (flags & FS_NOCOW_FL) {
247 if (S_ISREG(mode)) {
248 /*
249 * It's safe to turn csums off here, no extents exist.
250 * Otherwise we want the flag to reflect the real COW
251 * status of the file and will not set it.
252 */
253 if (inode->i_size == 0)
254 ip->flags |= BTRFS_INODE_NODATACOW
255 | BTRFS_INODE_NODATASUM;
256 } else {
257 ip->flags |= BTRFS_INODE_NODATACOW;
258 }
259 } else {
260 /*
261 * Revert back under same assuptions as above
262 */
263 if (S_ISREG(mode)) {
264 if (inode->i_size == 0)
265 ip->flags &= ~(BTRFS_INODE_NODATACOW
266 | BTRFS_INODE_NODATASUM);
267 } else {
268 ip->flags &= ~BTRFS_INODE_NODATACOW;
269 }
270 }
271
272 /*
273 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
274 * flag may be changed automatically if compression code won't make
275 * things smaller.
276 */
277 if (flags & FS_NOCOMP_FL) {
278 ip->flags &= ~BTRFS_INODE_COMPRESS;
279 ip->flags |= BTRFS_INODE_NOCOMPRESS;
280 } else if (flags & FS_COMPR_FL) {
281 ip->flags |= BTRFS_INODE_COMPRESS;
282 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
283 } else {
284 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
285 }
286
287 trans = btrfs_start_transaction(root, 1);
288 if (IS_ERR(trans)) {
289 ret = PTR_ERR(trans);
290 goto out_drop;
291 }
292
293 btrfs_update_iflags(inode);
294 inode_inc_iversion(inode);
295 inode->i_ctime = CURRENT_TIME;
296 ret = btrfs_update_inode(trans, root, inode);
297
298 btrfs_end_transaction(trans, root);
299 out_drop:
300 if (ret) {
301 ip->flags = ip_oldflags;
302 inode->i_flags = i_oldflags;
303 }
304
305 out_unlock:
306 mutex_unlock(&inode->i_mutex);
307 mnt_drop_write_file(file);
308 return ret;
309 }
310
311 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
312 {
313 struct inode *inode = file->f_path.dentry->d_inode;
314
315 return put_user(inode->i_generation, arg);
316 }
317
318 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
319 {
320 struct btrfs_fs_info *fs_info = btrfs_sb(fdentry(file)->d_sb);
321 struct btrfs_device *device;
322 struct request_queue *q;
323 struct fstrim_range range;
324 u64 minlen = ULLONG_MAX;
325 u64 num_devices = 0;
326 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
327 int ret;
328
329 if (!capable(CAP_SYS_ADMIN))
330 return -EPERM;
331
332 rcu_read_lock();
333 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
334 dev_list) {
335 if (!device->bdev)
336 continue;
337 q = bdev_get_queue(device->bdev);
338 if (blk_queue_discard(q)) {
339 num_devices++;
340 minlen = min((u64)q->limits.discard_granularity,
341 minlen);
342 }
343 }
344 rcu_read_unlock();
345
346 if (!num_devices)
347 return -EOPNOTSUPP;
348 if (copy_from_user(&range, arg, sizeof(range)))
349 return -EFAULT;
350 if (range.start > total_bytes ||
351 range.len < fs_info->sb->s_blocksize)
352 return -EINVAL;
353
354 range.len = min(range.len, total_bytes - range.start);
355 range.minlen = max(range.minlen, minlen);
356 ret = btrfs_trim_fs(fs_info->tree_root, &range);
357 if (ret < 0)
358 return ret;
359
360 if (copy_to_user(arg, &range, sizeof(range)))
361 return -EFAULT;
362
363 return 0;
364 }
365
366 static noinline int create_subvol(struct btrfs_root *root,
367 struct dentry *dentry,
368 char *name, int namelen,
369 u64 *async_transid,
370 struct btrfs_qgroup_inherit *inherit)
371 {
372 struct btrfs_trans_handle *trans;
373 struct btrfs_key key;
374 struct btrfs_root_item root_item;
375 struct btrfs_inode_item *inode_item;
376 struct extent_buffer *leaf;
377 struct btrfs_root *new_root;
378 struct dentry *parent = dentry->d_parent;
379 struct inode *dir;
380 struct timespec cur_time = CURRENT_TIME;
381 int ret;
382 int err;
383 u64 objectid;
384 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
385 u64 index = 0;
386 uuid_le new_uuid;
387
388 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
389 if (ret)
390 return ret;
391
392 dir = parent->d_inode;
393
394 /*
395 * 1 - inode item
396 * 2 - refs
397 * 1 - root item
398 * 2 - dir items
399 */
400 trans = btrfs_start_transaction(root, 6);
401 if (IS_ERR(trans))
402 return PTR_ERR(trans);
403
404 ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
405 if (ret)
406 goto fail;
407
408 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
409 0, objectid, NULL, 0, 0, 0);
410 if (IS_ERR(leaf)) {
411 ret = PTR_ERR(leaf);
412 goto fail;
413 }
414
415 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
416 btrfs_set_header_bytenr(leaf, leaf->start);
417 btrfs_set_header_generation(leaf, trans->transid);
418 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
419 btrfs_set_header_owner(leaf, objectid);
420
421 write_extent_buffer(leaf, root->fs_info->fsid,
422 (unsigned long)btrfs_header_fsid(leaf),
423 BTRFS_FSID_SIZE);
424 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
425 (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
426 BTRFS_UUID_SIZE);
427 btrfs_mark_buffer_dirty(leaf);
428
429 memset(&root_item, 0, sizeof(root_item));
430
431 inode_item = &root_item.inode;
432 inode_item->generation = cpu_to_le64(1);
433 inode_item->size = cpu_to_le64(3);
434 inode_item->nlink = cpu_to_le32(1);
435 inode_item->nbytes = cpu_to_le64(root->leafsize);
436 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
437
438 root_item.flags = 0;
439 root_item.byte_limit = 0;
440 inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
441
442 btrfs_set_root_bytenr(&root_item, leaf->start);
443 btrfs_set_root_generation(&root_item, trans->transid);
444 btrfs_set_root_level(&root_item, 0);
445 btrfs_set_root_refs(&root_item, 1);
446 btrfs_set_root_used(&root_item, leaf->len);
447 btrfs_set_root_last_snapshot(&root_item, 0);
448
449 btrfs_set_root_generation_v2(&root_item,
450 btrfs_root_generation(&root_item));
451 uuid_le_gen(&new_uuid);
452 memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
453 root_item.otime.sec = cpu_to_le64(cur_time.tv_sec);
454 root_item.otime.nsec = cpu_to_le32(cur_time.tv_nsec);
455 root_item.ctime = root_item.otime;
456 btrfs_set_root_ctransid(&root_item, trans->transid);
457 btrfs_set_root_otransid(&root_item, trans->transid);
458
459 btrfs_tree_unlock(leaf);
460 free_extent_buffer(leaf);
461 leaf = NULL;
462
463 btrfs_set_root_dirid(&root_item, new_dirid);
464
465 key.objectid = objectid;
466 key.offset = 0;
467 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
468 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
469 &root_item);
470 if (ret)
471 goto fail;
472
473 key.offset = (u64)-1;
474 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
475 if (IS_ERR(new_root)) {
476 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
477 ret = PTR_ERR(new_root);
478 goto fail;
479 }
480
481 btrfs_record_root_in_trans(trans, new_root);
482
483 ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
484 if (ret) {
485 /* We potentially lose an unused inode item here */
486 btrfs_abort_transaction(trans, root, ret);
487 goto fail;
488 }
489
490 /*
491 * insert the directory item
492 */
493 ret = btrfs_set_inode_index(dir, &index);
494 if (ret) {
495 btrfs_abort_transaction(trans, root, ret);
496 goto fail;
497 }
498
499 ret = btrfs_insert_dir_item(trans, root,
500 name, namelen, dir, &key,
501 BTRFS_FT_DIR, index);
502 if (ret) {
503 btrfs_abort_transaction(trans, root, ret);
504 goto fail;
505 }
506
507 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
508 ret = btrfs_update_inode(trans, root, dir);
509 BUG_ON(ret);
510
511 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
512 objectid, root->root_key.objectid,
513 btrfs_ino(dir), index, name, namelen);
514
515 BUG_ON(ret);
516
517 fail:
518 if (async_transid) {
519 *async_transid = trans->transid;
520 err = btrfs_commit_transaction_async(trans, root, 1);
521 } else {
522 err = btrfs_commit_transaction(trans, root);
523 }
524 if (err && !ret)
525 ret = err;
526
527 if (!ret)
528 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
529
530 return ret;
531 }
532
533 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
534 char *name, int namelen, u64 *async_transid,
535 bool readonly, struct btrfs_qgroup_inherit *inherit)
536 {
537 struct inode *inode;
538 struct btrfs_pending_snapshot *pending_snapshot;
539 struct btrfs_trans_handle *trans;
540 int ret;
541
542 if (!root->ref_cows)
543 return -EINVAL;
544
545 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
546 if (!pending_snapshot)
547 return -ENOMEM;
548
549 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
550 BTRFS_BLOCK_RSV_TEMP);
551 pending_snapshot->dentry = dentry;
552 pending_snapshot->root = root;
553 pending_snapshot->readonly = readonly;
554 pending_snapshot->inherit = inherit;
555
556 trans = btrfs_start_transaction(root->fs_info->extent_root, 6);
557 if (IS_ERR(trans)) {
558 ret = PTR_ERR(trans);
559 goto fail;
560 }
561
562 ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
563 BUG_ON(ret);
564
565 spin_lock(&root->fs_info->trans_lock);
566 list_add(&pending_snapshot->list,
567 &trans->transaction->pending_snapshots);
568 spin_unlock(&root->fs_info->trans_lock);
569 if (async_transid) {
570 *async_transid = trans->transid;
571 ret = btrfs_commit_transaction_async(trans,
572 root->fs_info->extent_root, 1);
573 } else {
574 ret = btrfs_commit_transaction(trans,
575 root->fs_info->extent_root);
576 }
577 if (ret) {
578 /* cleanup_transaction has freed this for us */
579 if (trans->aborted)
580 pending_snapshot = NULL;
581 goto fail;
582 }
583
584 ret = pending_snapshot->error;
585 if (ret)
586 goto fail;
587
588 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
589 if (ret)
590 goto fail;
591
592 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
593 if (IS_ERR(inode)) {
594 ret = PTR_ERR(inode);
595 goto fail;
596 }
597 BUG_ON(!inode);
598 d_instantiate(dentry, inode);
599 ret = 0;
600 fail:
601 kfree(pending_snapshot);
602 return ret;
603 }
604
605 /* copy of check_sticky in fs/namei.c()
606 * It's inline, so penalty for filesystems that don't use sticky bit is
607 * minimal.
608 */
609 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
610 {
611 kuid_t fsuid = current_fsuid();
612
613 if (!(dir->i_mode & S_ISVTX))
614 return 0;
615 if (uid_eq(inode->i_uid, fsuid))
616 return 0;
617 if (uid_eq(dir->i_uid, fsuid))
618 return 0;
619 return !capable(CAP_FOWNER);
620 }
621
622 /* copy of may_delete in fs/namei.c()
623 * Check whether we can remove a link victim from directory dir, check
624 * whether the type of victim is right.
625 * 1. We can't do it if dir is read-only (done in permission())
626 * 2. We should have write and exec permissions on dir
627 * 3. We can't remove anything from append-only dir
628 * 4. We can't do anything with immutable dir (done in permission())
629 * 5. If the sticky bit on dir is set we should either
630 * a. be owner of dir, or
631 * b. be owner of victim, or
632 * c. have CAP_FOWNER capability
633 * 6. If the victim is append-only or immutable we can't do antyhing with
634 * links pointing to it.
635 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
636 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
637 * 9. We can't remove a root or mountpoint.
638 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
639 * nfs_async_unlink().
640 */
641
642 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
643 {
644 int error;
645
646 if (!victim->d_inode)
647 return -ENOENT;
648
649 BUG_ON(victim->d_parent->d_inode != dir);
650 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
651
652 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
653 if (error)
654 return error;
655 if (IS_APPEND(dir))
656 return -EPERM;
657 if (btrfs_check_sticky(dir, victim->d_inode)||
658 IS_APPEND(victim->d_inode)||
659 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
660 return -EPERM;
661 if (isdir) {
662 if (!S_ISDIR(victim->d_inode->i_mode))
663 return -ENOTDIR;
664 if (IS_ROOT(victim))
665 return -EBUSY;
666 } else if (S_ISDIR(victim->d_inode->i_mode))
667 return -EISDIR;
668 if (IS_DEADDIR(dir))
669 return -ENOENT;
670 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
671 return -EBUSY;
672 return 0;
673 }
674
675 /* copy of may_create in fs/namei.c() */
676 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
677 {
678 if (child->d_inode)
679 return -EEXIST;
680 if (IS_DEADDIR(dir))
681 return -ENOENT;
682 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
683 }
684
685 /*
686 * Create a new subvolume below @parent. This is largely modeled after
687 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
688 * inside this filesystem so it's quite a bit simpler.
689 */
690 static noinline int btrfs_mksubvol(struct path *parent,
691 char *name, int namelen,
692 struct btrfs_root *snap_src,
693 u64 *async_transid, bool readonly,
694 struct btrfs_qgroup_inherit *inherit)
695 {
696 struct inode *dir = parent->dentry->d_inode;
697 struct dentry *dentry;
698 int error;
699
700 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
701
702 dentry = lookup_one_len(name, parent->dentry, namelen);
703 error = PTR_ERR(dentry);
704 if (IS_ERR(dentry))
705 goto out_unlock;
706
707 error = -EEXIST;
708 if (dentry->d_inode)
709 goto out_dput;
710
711 error = btrfs_may_create(dir, dentry);
712 if (error)
713 goto out_dput;
714
715 /*
716 * even if this name doesn't exist, we may get hash collisions.
717 * check for them now when we can safely fail
718 */
719 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
720 dir->i_ino, name,
721 namelen);
722 if (error)
723 goto out_dput;
724
725 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
726
727 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
728 goto out_up_read;
729
730 if (snap_src) {
731 error = create_snapshot(snap_src, dentry, name, namelen,
732 async_transid, readonly, inherit);
733 } else {
734 error = create_subvol(BTRFS_I(dir)->root, dentry,
735 name, namelen, async_transid, inherit);
736 }
737 if (!error)
738 fsnotify_mkdir(dir, dentry);
739 out_up_read:
740 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
741 out_dput:
742 dput(dentry);
743 out_unlock:
744 mutex_unlock(&dir->i_mutex);
745 return error;
746 }
747
748 /*
749 * When we're defragging a range, we don't want to kick it off again
750 * if it is really just waiting for delalloc to send it down.
751 * If we find a nice big extent or delalloc range for the bytes in the
752 * file you want to defrag, we return 0 to let you know to skip this
753 * part of the file
754 */
755 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
756 {
757 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
758 struct extent_map *em = NULL;
759 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
760 u64 end;
761
762 read_lock(&em_tree->lock);
763 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
764 read_unlock(&em_tree->lock);
765
766 if (em) {
767 end = extent_map_end(em);
768 free_extent_map(em);
769 if (end - offset > thresh)
770 return 0;
771 }
772 /* if we already have a nice delalloc here, just stop */
773 thresh /= 2;
774 end = count_range_bits(io_tree, &offset, offset + thresh,
775 thresh, EXTENT_DELALLOC, 1);
776 if (end >= thresh)
777 return 0;
778 return 1;
779 }
780
781 /*
782 * helper function to walk through a file and find extents
783 * newer than a specific transid, and smaller than thresh.
784 *
785 * This is used by the defragging code to find new and small
786 * extents
787 */
788 static int find_new_extents(struct btrfs_root *root,
789 struct inode *inode, u64 newer_than,
790 u64 *off, int thresh)
791 {
792 struct btrfs_path *path;
793 struct btrfs_key min_key;
794 struct btrfs_key max_key;
795 struct extent_buffer *leaf;
796 struct btrfs_file_extent_item *extent;
797 int type;
798 int ret;
799 u64 ino = btrfs_ino(inode);
800
801 path = btrfs_alloc_path();
802 if (!path)
803 return -ENOMEM;
804
805 min_key.objectid = ino;
806 min_key.type = BTRFS_EXTENT_DATA_KEY;
807 min_key.offset = *off;
808
809 max_key.objectid = ino;
810 max_key.type = (u8)-1;
811 max_key.offset = (u64)-1;
812
813 path->keep_locks = 1;
814
815 while(1) {
816 ret = btrfs_search_forward(root, &min_key, &max_key,
817 path, newer_than);
818 if (ret != 0)
819 goto none;
820 if (min_key.objectid != ino)
821 goto none;
822 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
823 goto none;
824
825 leaf = path->nodes[0];
826 extent = btrfs_item_ptr(leaf, path->slots[0],
827 struct btrfs_file_extent_item);
828
829 type = btrfs_file_extent_type(leaf, extent);
830 if (type == BTRFS_FILE_EXTENT_REG &&
831 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
832 check_defrag_in_cache(inode, min_key.offset, thresh)) {
833 *off = min_key.offset;
834 btrfs_free_path(path);
835 return 0;
836 }
837
838 if (min_key.offset == (u64)-1)
839 goto none;
840
841 min_key.offset++;
842 btrfs_release_path(path);
843 }
844 none:
845 btrfs_free_path(path);
846 return -ENOENT;
847 }
848
849 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
850 {
851 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
852 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
853 struct extent_map *em;
854 u64 len = PAGE_CACHE_SIZE;
855
856 /*
857 * hopefully we have this extent in the tree already, try without
858 * the full extent lock
859 */
860 read_lock(&em_tree->lock);
861 em = lookup_extent_mapping(em_tree, start, len);
862 read_unlock(&em_tree->lock);
863
864 if (!em) {
865 /* get the big lock and read metadata off disk */
866 lock_extent(io_tree, start, start + len - 1);
867 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
868 unlock_extent(io_tree, start, start + len - 1);
869
870 if (IS_ERR(em))
871 return NULL;
872 }
873
874 return em;
875 }
876
877 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
878 {
879 struct extent_map *next;
880 bool ret = true;
881
882 /* this is the last extent */
883 if (em->start + em->len >= i_size_read(inode))
884 return false;
885
886 next = defrag_lookup_extent(inode, em->start + em->len);
887 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
888 ret = false;
889
890 free_extent_map(next);
891 return ret;
892 }
893
894 static int should_defrag_range(struct inode *inode, u64 start, int thresh,
895 u64 *last_len, u64 *skip, u64 *defrag_end,
896 int compress)
897 {
898 struct extent_map *em;
899 int ret = 1;
900 bool next_mergeable = true;
901
902 /*
903 * make sure that once we start defragging an extent, we keep on
904 * defragging it
905 */
906 if (start < *defrag_end)
907 return 1;
908
909 *skip = 0;
910
911 em = defrag_lookup_extent(inode, start);
912 if (!em)
913 return 0;
914
915 /* this will cover holes, and inline extents */
916 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
917 ret = 0;
918 goto out;
919 }
920
921 next_mergeable = defrag_check_next_extent(inode, em);
922
923 /*
924 * we hit a real extent, if it is big or the next extent is not a
925 * real extent, don't bother defragging it
926 */
927 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
928 (em->len >= thresh || !next_mergeable))
929 ret = 0;
930 out:
931 /*
932 * last_len ends up being a counter of how many bytes we've defragged.
933 * every time we choose not to defrag an extent, we reset *last_len
934 * so that the next tiny extent will force a defrag.
935 *
936 * The end result of this is that tiny extents before a single big
937 * extent will force at least part of that big extent to be defragged.
938 */
939 if (ret) {
940 *defrag_end = extent_map_end(em);
941 } else {
942 *last_len = 0;
943 *skip = extent_map_end(em);
944 *defrag_end = 0;
945 }
946
947 free_extent_map(em);
948 return ret;
949 }
950
951 /*
952 * it doesn't do much good to defrag one or two pages
953 * at a time. This pulls in a nice chunk of pages
954 * to COW and defrag.
955 *
956 * It also makes sure the delalloc code has enough
957 * dirty data to avoid making new small extents as part
958 * of the defrag
959 *
960 * It's a good idea to start RA on this range
961 * before calling this.
962 */
963 static int cluster_pages_for_defrag(struct inode *inode,
964 struct page **pages,
965 unsigned long start_index,
966 int num_pages)
967 {
968 unsigned long file_end;
969 u64 isize = i_size_read(inode);
970 u64 page_start;
971 u64 page_end;
972 u64 page_cnt;
973 int ret;
974 int i;
975 int i_done;
976 struct btrfs_ordered_extent *ordered;
977 struct extent_state *cached_state = NULL;
978 struct extent_io_tree *tree;
979 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
980
981 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
982 if (!isize || start_index > file_end)
983 return 0;
984
985 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
986
987 ret = btrfs_delalloc_reserve_space(inode,
988 page_cnt << PAGE_CACHE_SHIFT);
989 if (ret)
990 return ret;
991 i_done = 0;
992 tree = &BTRFS_I(inode)->io_tree;
993
994 /* step one, lock all the pages */
995 for (i = 0; i < page_cnt; i++) {
996 struct page *page;
997 again:
998 page = find_or_create_page(inode->i_mapping,
999 start_index + i, mask);
1000 if (!page)
1001 break;
1002
1003 page_start = page_offset(page);
1004 page_end = page_start + PAGE_CACHE_SIZE - 1;
1005 while (1) {
1006 lock_extent(tree, page_start, page_end);
1007 ordered = btrfs_lookup_ordered_extent(inode,
1008 page_start);
1009 unlock_extent(tree, page_start, page_end);
1010 if (!ordered)
1011 break;
1012
1013 unlock_page(page);
1014 btrfs_start_ordered_extent(inode, ordered, 1);
1015 btrfs_put_ordered_extent(ordered);
1016 lock_page(page);
1017 /*
1018 * we unlocked the page above, so we need check if
1019 * it was released or not.
1020 */
1021 if (page->mapping != inode->i_mapping) {
1022 unlock_page(page);
1023 page_cache_release(page);
1024 goto again;
1025 }
1026 }
1027
1028 if (!PageUptodate(page)) {
1029 btrfs_readpage(NULL, page);
1030 lock_page(page);
1031 if (!PageUptodate(page)) {
1032 unlock_page(page);
1033 page_cache_release(page);
1034 ret = -EIO;
1035 break;
1036 }
1037 }
1038
1039 if (page->mapping != inode->i_mapping) {
1040 unlock_page(page);
1041 page_cache_release(page);
1042 goto again;
1043 }
1044
1045 pages[i] = page;
1046 i_done++;
1047 }
1048 if (!i_done || ret)
1049 goto out;
1050
1051 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1052 goto out;
1053
1054 /*
1055 * so now we have a nice long stream of locked
1056 * and up to date pages, lets wait on them
1057 */
1058 for (i = 0; i < i_done; i++)
1059 wait_on_page_writeback(pages[i]);
1060
1061 page_start = page_offset(pages[0]);
1062 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1063
1064 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1065 page_start, page_end - 1, 0, &cached_state);
1066 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1067 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1068 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1069 &cached_state, GFP_NOFS);
1070
1071 if (i_done != page_cnt) {
1072 spin_lock(&BTRFS_I(inode)->lock);
1073 BTRFS_I(inode)->outstanding_extents++;
1074 spin_unlock(&BTRFS_I(inode)->lock);
1075 btrfs_delalloc_release_space(inode,
1076 (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1077 }
1078
1079
1080 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1081 &cached_state, GFP_NOFS);
1082
1083 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1084 page_start, page_end - 1, &cached_state,
1085 GFP_NOFS);
1086
1087 for (i = 0; i < i_done; i++) {
1088 clear_page_dirty_for_io(pages[i]);
1089 ClearPageChecked(pages[i]);
1090 set_page_extent_mapped(pages[i]);
1091 set_page_dirty(pages[i]);
1092 unlock_page(pages[i]);
1093 page_cache_release(pages[i]);
1094 }
1095 return i_done;
1096 out:
1097 for (i = 0; i < i_done; i++) {
1098 unlock_page(pages[i]);
1099 page_cache_release(pages[i]);
1100 }
1101 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1102 return ret;
1103
1104 }
1105
1106 int btrfs_defrag_file(struct inode *inode, struct file *file,
1107 struct btrfs_ioctl_defrag_range_args *range,
1108 u64 newer_than, unsigned long max_to_defrag)
1109 {
1110 struct btrfs_root *root = BTRFS_I(inode)->root;
1111 struct file_ra_state *ra = NULL;
1112 unsigned long last_index;
1113 u64 isize = i_size_read(inode);
1114 u64 last_len = 0;
1115 u64 skip = 0;
1116 u64 defrag_end = 0;
1117 u64 newer_off = range->start;
1118 unsigned long i;
1119 unsigned long ra_index = 0;
1120 int ret;
1121 int defrag_count = 0;
1122 int compress_type = BTRFS_COMPRESS_ZLIB;
1123 int extent_thresh = range->extent_thresh;
1124 int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1125 int cluster = max_cluster;
1126 u64 new_align = ~((u64)128 * 1024 - 1);
1127 struct page **pages = NULL;
1128
1129 if (extent_thresh == 0)
1130 extent_thresh = 256 * 1024;
1131
1132 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1133 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1134 return -EINVAL;
1135 if (range->compress_type)
1136 compress_type = range->compress_type;
1137 }
1138
1139 if (isize == 0)
1140 return 0;
1141
1142 /*
1143 * if we were not given a file, allocate a readahead
1144 * context
1145 */
1146 if (!file) {
1147 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1148 if (!ra)
1149 return -ENOMEM;
1150 file_ra_state_init(ra, inode->i_mapping);
1151 } else {
1152 ra = &file->f_ra;
1153 }
1154
1155 pages = kmalloc(sizeof(struct page *) * max_cluster,
1156 GFP_NOFS);
1157 if (!pages) {
1158 ret = -ENOMEM;
1159 goto out_ra;
1160 }
1161
1162 /* find the last page to defrag */
1163 if (range->start + range->len > range->start) {
1164 last_index = min_t(u64, isize - 1,
1165 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1166 } else {
1167 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1168 }
1169
1170 if (newer_than) {
1171 ret = find_new_extents(root, inode, newer_than,
1172 &newer_off, 64 * 1024);
1173 if (!ret) {
1174 range->start = newer_off;
1175 /*
1176 * we always align our defrag to help keep
1177 * the extents in the file evenly spaced
1178 */
1179 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1180 } else
1181 goto out_ra;
1182 } else {
1183 i = range->start >> PAGE_CACHE_SHIFT;
1184 }
1185 if (!max_to_defrag)
1186 max_to_defrag = last_index + 1;
1187
1188 /*
1189 * make writeback starts from i, so the defrag range can be
1190 * written sequentially.
1191 */
1192 if (i < inode->i_mapping->writeback_index)
1193 inode->i_mapping->writeback_index = i;
1194
1195 while (i <= last_index && defrag_count < max_to_defrag &&
1196 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1197 PAGE_CACHE_SHIFT)) {
1198 /*
1199 * make sure we stop running if someone unmounts
1200 * the FS
1201 */
1202 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1203 break;
1204
1205 if (btrfs_defrag_cancelled(root->fs_info)) {
1206 printk(KERN_DEBUG "btrfs: defrag_file cancelled\n");
1207 ret = -EAGAIN;
1208 break;
1209 }
1210
1211 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1212 extent_thresh, &last_len, &skip,
1213 &defrag_end, range->flags &
1214 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1215 unsigned long next;
1216 /*
1217 * the should_defrag function tells us how much to skip
1218 * bump our counter by the suggested amount
1219 */
1220 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1221 i = max(i + 1, next);
1222 continue;
1223 }
1224
1225 if (!newer_than) {
1226 cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1227 PAGE_CACHE_SHIFT) - i;
1228 cluster = min(cluster, max_cluster);
1229 } else {
1230 cluster = max_cluster;
1231 }
1232
1233 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1234 BTRFS_I(inode)->force_compress = compress_type;
1235
1236 if (i + cluster > ra_index) {
1237 ra_index = max(i, ra_index);
1238 btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1239 cluster);
1240 ra_index += max_cluster;
1241 }
1242
1243 mutex_lock(&inode->i_mutex);
1244 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1245 if (ret < 0) {
1246 mutex_unlock(&inode->i_mutex);
1247 goto out_ra;
1248 }
1249
1250 defrag_count += ret;
1251 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
1252 mutex_unlock(&inode->i_mutex);
1253
1254 if (newer_than) {
1255 if (newer_off == (u64)-1)
1256 break;
1257
1258 if (ret > 0)
1259 i += ret;
1260
1261 newer_off = max(newer_off + 1,
1262 (u64)i << PAGE_CACHE_SHIFT);
1263
1264 ret = find_new_extents(root, inode,
1265 newer_than, &newer_off,
1266 64 * 1024);
1267 if (!ret) {
1268 range->start = newer_off;
1269 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1270 } else {
1271 break;
1272 }
1273 } else {
1274 if (ret > 0) {
1275 i += ret;
1276 last_len += ret << PAGE_CACHE_SHIFT;
1277 } else {
1278 i++;
1279 last_len = 0;
1280 }
1281 }
1282 }
1283
1284 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1285 filemap_flush(inode->i_mapping);
1286
1287 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1288 /* the filemap_flush will queue IO into the worker threads, but
1289 * we have to make sure the IO is actually started and that
1290 * ordered extents get created before we return
1291 */
1292 atomic_inc(&root->fs_info->async_submit_draining);
1293 while (atomic_read(&root->fs_info->nr_async_submits) ||
1294 atomic_read(&root->fs_info->async_delalloc_pages)) {
1295 wait_event(root->fs_info->async_submit_wait,
1296 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1297 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1298 }
1299 atomic_dec(&root->fs_info->async_submit_draining);
1300
1301 mutex_lock(&inode->i_mutex);
1302 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1303 mutex_unlock(&inode->i_mutex);
1304 }
1305
1306 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1307 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1308 }
1309
1310 ret = defrag_count;
1311
1312 out_ra:
1313 if (!file)
1314 kfree(ra);
1315 kfree(pages);
1316 return ret;
1317 }
1318
1319 static noinline int btrfs_ioctl_resize(struct file *file,
1320 void __user *arg)
1321 {
1322 u64 new_size;
1323 u64 old_size;
1324 u64 devid = 1;
1325 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1326 struct btrfs_ioctl_vol_args *vol_args;
1327 struct btrfs_trans_handle *trans;
1328 struct btrfs_device *device = NULL;
1329 char *sizestr;
1330 char *devstr = NULL;
1331 int ret = 0;
1332 int mod = 0;
1333
1334 if (!capable(CAP_SYS_ADMIN))
1335 return -EPERM;
1336
1337 ret = mnt_want_write_file(file);
1338 if (ret)
1339 return ret;
1340
1341 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1342 1)) {
1343 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
1344 mnt_drop_write_file(file);
1345 return -EINVAL;
1346 }
1347
1348 mutex_lock(&root->fs_info->volume_mutex);
1349 vol_args = memdup_user(arg, sizeof(*vol_args));
1350 if (IS_ERR(vol_args)) {
1351 ret = PTR_ERR(vol_args);
1352 goto out;
1353 }
1354
1355 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1356
1357 sizestr = vol_args->name;
1358 devstr = strchr(sizestr, ':');
1359 if (devstr) {
1360 char *end;
1361 sizestr = devstr + 1;
1362 *devstr = '\0';
1363 devstr = vol_args->name;
1364 devid = simple_strtoull(devstr, &end, 10);
1365 if (!devid) {
1366 ret = -EINVAL;
1367 goto out_free;
1368 }
1369 printk(KERN_INFO "btrfs: resizing devid %llu\n",
1370 (unsigned long long)devid);
1371 }
1372
1373 device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1374 if (!device) {
1375 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n",
1376 (unsigned long long)devid);
1377 ret = -ENODEV;
1378 goto out_free;
1379 }
1380
1381 if (!device->writeable) {
1382 printk(KERN_INFO "btrfs: resizer unable to apply on "
1383 "readonly device %llu\n",
1384 (unsigned long long)devid);
1385 ret = -EPERM;
1386 goto out_free;
1387 }
1388
1389 if (!strcmp(sizestr, "max"))
1390 new_size = device->bdev->bd_inode->i_size;
1391 else {
1392 if (sizestr[0] == '-') {
1393 mod = -1;
1394 sizestr++;
1395 } else if (sizestr[0] == '+') {
1396 mod = 1;
1397 sizestr++;
1398 }
1399 new_size = memparse(sizestr, NULL);
1400 if (new_size == 0) {
1401 ret = -EINVAL;
1402 goto out_free;
1403 }
1404 }
1405
1406 if (device->is_tgtdev_for_dev_replace) {
1407 ret = -EPERM;
1408 goto out_free;
1409 }
1410
1411 old_size = device->total_bytes;
1412
1413 if (mod < 0) {
1414 if (new_size > old_size) {
1415 ret = -EINVAL;
1416 goto out_free;
1417 }
1418 new_size = old_size - new_size;
1419 } else if (mod > 0) {
1420 new_size = old_size + new_size;
1421 }
1422
1423 if (new_size < 256 * 1024 * 1024) {
1424 ret = -EINVAL;
1425 goto out_free;
1426 }
1427 if (new_size > device->bdev->bd_inode->i_size) {
1428 ret = -EFBIG;
1429 goto out_free;
1430 }
1431
1432 do_div(new_size, root->sectorsize);
1433 new_size *= root->sectorsize;
1434
1435 printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n",
1436 rcu_str_deref(device->name),
1437 (unsigned long long)new_size);
1438
1439 if (new_size > old_size) {
1440 trans = btrfs_start_transaction(root, 0);
1441 if (IS_ERR(trans)) {
1442 ret = PTR_ERR(trans);
1443 goto out_free;
1444 }
1445 ret = btrfs_grow_device(trans, device, new_size);
1446 btrfs_commit_transaction(trans, root);
1447 } else if (new_size < old_size) {
1448 ret = btrfs_shrink_device(device, new_size);
1449 } /* equal, nothing need to do */
1450
1451 out_free:
1452 kfree(vol_args);
1453 out:
1454 mutex_unlock(&root->fs_info->volume_mutex);
1455 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1456 mnt_drop_write_file(file);
1457 return ret;
1458 }
1459
1460 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1461 char *name, unsigned long fd, int subvol,
1462 u64 *transid, bool readonly,
1463 struct btrfs_qgroup_inherit *inherit)
1464 {
1465 int namelen;
1466 int ret = 0;
1467
1468 ret = mnt_want_write_file(file);
1469 if (ret)
1470 goto out;
1471
1472 namelen = strlen(name);
1473 if (strchr(name, '/')) {
1474 ret = -EINVAL;
1475 goto out_drop_write;
1476 }
1477
1478 if (name[0] == '.' &&
1479 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1480 ret = -EEXIST;
1481 goto out_drop_write;
1482 }
1483
1484 if (subvol) {
1485 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1486 NULL, transid, readonly, inherit);
1487 } else {
1488 struct fd src = fdget(fd);
1489 struct inode *src_inode;
1490 if (!src.file) {
1491 ret = -EINVAL;
1492 goto out_drop_write;
1493 }
1494
1495 src_inode = src.file->f_path.dentry->d_inode;
1496 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1497 printk(KERN_INFO "btrfs: Snapshot src from "
1498 "another FS\n");
1499 ret = -EINVAL;
1500 } else {
1501 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1502 BTRFS_I(src_inode)->root,
1503 transid, readonly, inherit);
1504 }
1505 fdput(src);
1506 }
1507 out_drop_write:
1508 mnt_drop_write_file(file);
1509 out:
1510 return ret;
1511 }
1512
1513 static noinline int btrfs_ioctl_snap_create(struct file *file,
1514 void __user *arg, int subvol)
1515 {
1516 struct btrfs_ioctl_vol_args *vol_args;
1517 int ret;
1518
1519 vol_args = memdup_user(arg, sizeof(*vol_args));
1520 if (IS_ERR(vol_args))
1521 return PTR_ERR(vol_args);
1522 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1523
1524 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1525 vol_args->fd, subvol,
1526 NULL, false, NULL);
1527
1528 kfree(vol_args);
1529 return ret;
1530 }
1531
1532 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1533 void __user *arg, int subvol)
1534 {
1535 struct btrfs_ioctl_vol_args_v2 *vol_args;
1536 int ret;
1537 u64 transid = 0;
1538 u64 *ptr = NULL;
1539 bool readonly = false;
1540 struct btrfs_qgroup_inherit *inherit = NULL;
1541
1542 vol_args = memdup_user(arg, sizeof(*vol_args));
1543 if (IS_ERR(vol_args))
1544 return PTR_ERR(vol_args);
1545 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1546
1547 if (vol_args->flags &
1548 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1549 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1550 ret = -EOPNOTSUPP;
1551 goto out;
1552 }
1553
1554 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1555 ptr = &transid;
1556 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1557 readonly = true;
1558 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1559 if (vol_args->size > PAGE_CACHE_SIZE) {
1560 ret = -EINVAL;
1561 goto out;
1562 }
1563 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1564 if (IS_ERR(inherit)) {
1565 ret = PTR_ERR(inherit);
1566 goto out;
1567 }
1568 }
1569
1570 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1571 vol_args->fd, subvol, ptr,
1572 readonly, inherit);
1573
1574 if (ret == 0 && ptr &&
1575 copy_to_user(arg +
1576 offsetof(struct btrfs_ioctl_vol_args_v2,
1577 transid), ptr, sizeof(*ptr)))
1578 ret = -EFAULT;
1579 out:
1580 kfree(vol_args);
1581 kfree(inherit);
1582 return ret;
1583 }
1584
1585 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1586 void __user *arg)
1587 {
1588 struct inode *inode = fdentry(file)->d_inode;
1589 struct btrfs_root *root = BTRFS_I(inode)->root;
1590 int ret = 0;
1591 u64 flags = 0;
1592
1593 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1594 return -EINVAL;
1595
1596 down_read(&root->fs_info->subvol_sem);
1597 if (btrfs_root_readonly(root))
1598 flags |= BTRFS_SUBVOL_RDONLY;
1599 up_read(&root->fs_info->subvol_sem);
1600
1601 if (copy_to_user(arg, &flags, sizeof(flags)))
1602 ret = -EFAULT;
1603
1604 return ret;
1605 }
1606
1607 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1608 void __user *arg)
1609 {
1610 struct inode *inode = fdentry(file)->d_inode;
1611 struct btrfs_root *root = BTRFS_I(inode)->root;
1612 struct btrfs_trans_handle *trans;
1613 u64 root_flags;
1614 u64 flags;
1615 int ret = 0;
1616
1617 ret = mnt_want_write_file(file);
1618 if (ret)
1619 goto out;
1620
1621 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1622 ret = -EINVAL;
1623 goto out_drop_write;
1624 }
1625
1626 if (copy_from_user(&flags, arg, sizeof(flags))) {
1627 ret = -EFAULT;
1628 goto out_drop_write;
1629 }
1630
1631 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1632 ret = -EINVAL;
1633 goto out_drop_write;
1634 }
1635
1636 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1637 ret = -EOPNOTSUPP;
1638 goto out_drop_write;
1639 }
1640
1641 if (!inode_owner_or_capable(inode)) {
1642 ret = -EACCES;
1643 goto out_drop_write;
1644 }
1645
1646 down_write(&root->fs_info->subvol_sem);
1647
1648 /* nothing to do */
1649 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1650 goto out_drop_sem;
1651
1652 root_flags = btrfs_root_flags(&root->root_item);
1653 if (flags & BTRFS_SUBVOL_RDONLY)
1654 btrfs_set_root_flags(&root->root_item,
1655 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1656 else
1657 btrfs_set_root_flags(&root->root_item,
1658 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1659
1660 trans = btrfs_start_transaction(root, 1);
1661 if (IS_ERR(trans)) {
1662 ret = PTR_ERR(trans);
1663 goto out_reset;
1664 }
1665
1666 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1667 &root->root_key, &root->root_item);
1668
1669 btrfs_commit_transaction(trans, root);
1670 out_reset:
1671 if (ret)
1672 btrfs_set_root_flags(&root->root_item, root_flags);
1673 out_drop_sem:
1674 up_write(&root->fs_info->subvol_sem);
1675 out_drop_write:
1676 mnt_drop_write_file(file);
1677 out:
1678 return ret;
1679 }
1680
1681 /*
1682 * helper to check if the subvolume references other subvolumes
1683 */
1684 static noinline int may_destroy_subvol(struct btrfs_root *root)
1685 {
1686 struct btrfs_path *path;
1687 struct btrfs_key key;
1688 int ret;
1689
1690 path = btrfs_alloc_path();
1691 if (!path)
1692 return -ENOMEM;
1693
1694 key.objectid = root->root_key.objectid;
1695 key.type = BTRFS_ROOT_REF_KEY;
1696 key.offset = (u64)-1;
1697
1698 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1699 &key, path, 0, 0);
1700 if (ret < 0)
1701 goto out;
1702 BUG_ON(ret == 0);
1703
1704 ret = 0;
1705 if (path->slots[0] > 0) {
1706 path->slots[0]--;
1707 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1708 if (key.objectid == root->root_key.objectid &&
1709 key.type == BTRFS_ROOT_REF_KEY)
1710 ret = -ENOTEMPTY;
1711 }
1712 out:
1713 btrfs_free_path(path);
1714 return ret;
1715 }
1716
1717 static noinline int key_in_sk(struct btrfs_key *key,
1718 struct btrfs_ioctl_search_key *sk)
1719 {
1720 struct btrfs_key test;
1721 int ret;
1722
1723 test.objectid = sk->min_objectid;
1724 test.type = sk->min_type;
1725 test.offset = sk->min_offset;
1726
1727 ret = btrfs_comp_cpu_keys(key, &test);
1728 if (ret < 0)
1729 return 0;
1730
1731 test.objectid = sk->max_objectid;
1732 test.type = sk->max_type;
1733 test.offset = sk->max_offset;
1734
1735 ret = btrfs_comp_cpu_keys(key, &test);
1736 if (ret > 0)
1737 return 0;
1738 return 1;
1739 }
1740
1741 static noinline int copy_to_sk(struct btrfs_root *root,
1742 struct btrfs_path *path,
1743 struct btrfs_key *key,
1744 struct btrfs_ioctl_search_key *sk,
1745 char *buf,
1746 unsigned long *sk_offset,
1747 int *num_found)
1748 {
1749 u64 found_transid;
1750 struct extent_buffer *leaf;
1751 struct btrfs_ioctl_search_header sh;
1752 unsigned long item_off;
1753 unsigned long item_len;
1754 int nritems;
1755 int i;
1756 int slot;
1757 int ret = 0;
1758
1759 leaf = path->nodes[0];
1760 slot = path->slots[0];
1761 nritems = btrfs_header_nritems(leaf);
1762
1763 if (btrfs_header_generation(leaf) > sk->max_transid) {
1764 i = nritems;
1765 goto advance_key;
1766 }
1767 found_transid = btrfs_header_generation(leaf);
1768
1769 for (i = slot; i < nritems; i++) {
1770 item_off = btrfs_item_ptr_offset(leaf, i);
1771 item_len = btrfs_item_size_nr(leaf, i);
1772
1773 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1774 item_len = 0;
1775
1776 if (sizeof(sh) + item_len + *sk_offset >
1777 BTRFS_SEARCH_ARGS_BUFSIZE) {
1778 ret = 1;
1779 goto overflow;
1780 }
1781
1782 btrfs_item_key_to_cpu(leaf, key, i);
1783 if (!key_in_sk(key, sk))
1784 continue;
1785
1786 sh.objectid = key->objectid;
1787 sh.offset = key->offset;
1788 sh.type = key->type;
1789 sh.len = item_len;
1790 sh.transid = found_transid;
1791
1792 /* copy search result header */
1793 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1794 *sk_offset += sizeof(sh);
1795
1796 if (item_len) {
1797 char *p = buf + *sk_offset;
1798 /* copy the item */
1799 read_extent_buffer(leaf, p,
1800 item_off, item_len);
1801 *sk_offset += item_len;
1802 }
1803 (*num_found)++;
1804
1805 if (*num_found >= sk->nr_items)
1806 break;
1807 }
1808 advance_key:
1809 ret = 0;
1810 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1811 key->offset++;
1812 else if (key->type < (u8)-1 && key->type < sk->max_type) {
1813 key->offset = 0;
1814 key->type++;
1815 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1816 key->offset = 0;
1817 key->type = 0;
1818 key->objectid++;
1819 } else
1820 ret = 1;
1821 overflow:
1822 return ret;
1823 }
1824
1825 static noinline int search_ioctl(struct inode *inode,
1826 struct btrfs_ioctl_search_args *args)
1827 {
1828 struct btrfs_root *root;
1829 struct btrfs_key key;
1830 struct btrfs_key max_key;
1831 struct btrfs_path *path;
1832 struct btrfs_ioctl_search_key *sk = &args->key;
1833 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1834 int ret;
1835 int num_found = 0;
1836 unsigned long sk_offset = 0;
1837
1838 path = btrfs_alloc_path();
1839 if (!path)
1840 return -ENOMEM;
1841
1842 if (sk->tree_id == 0) {
1843 /* search the root of the inode that was passed */
1844 root = BTRFS_I(inode)->root;
1845 } else {
1846 key.objectid = sk->tree_id;
1847 key.type = BTRFS_ROOT_ITEM_KEY;
1848 key.offset = (u64)-1;
1849 root = btrfs_read_fs_root_no_name(info, &key);
1850 if (IS_ERR(root)) {
1851 printk(KERN_ERR "could not find root %llu\n",
1852 sk->tree_id);
1853 btrfs_free_path(path);
1854 return -ENOENT;
1855 }
1856 }
1857
1858 key.objectid = sk->min_objectid;
1859 key.type = sk->min_type;
1860 key.offset = sk->min_offset;
1861
1862 max_key.objectid = sk->max_objectid;
1863 max_key.type = sk->max_type;
1864 max_key.offset = sk->max_offset;
1865
1866 path->keep_locks = 1;
1867
1868 while(1) {
1869 ret = btrfs_search_forward(root, &key, &max_key, path,
1870 sk->min_transid);
1871 if (ret != 0) {
1872 if (ret > 0)
1873 ret = 0;
1874 goto err;
1875 }
1876 ret = copy_to_sk(root, path, &key, sk, args->buf,
1877 &sk_offset, &num_found);
1878 btrfs_release_path(path);
1879 if (ret || num_found >= sk->nr_items)
1880 break;
1881
1882 }
1883 ret = 0;
1884 err:
1885 sk->nr_items = num_found;
1886 btrfs_free_path(path);
1887 return ret;
1888 }
1889
1890 static noinline int btrfs_ioctl_tree_search(struct file *file,
1891 void __user *argp)
1892 {
1893 struct btrfs_ioctl_search_args *args;
1894 struct inode *inode;
1895 int ret;
1896
1897 if (!capable(CAP_SYS_ADMIN))
1898 return -EPERM;
1899
1900 args = memdup_user(argp, sizeof(*args));
1901 if (IS_ERR(args))
1902 return PTR_ERR(args);
1903
1904 inode = fdentry(file)->d_inode;
1905 ret = search_ioctl(inode, args);
1906 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1907 ret = -EFAULT;
1908 kfree(args);
1909 return ret;
1910 }
1911
1912 /*
1913 * Search INODE_REFs to identify path name of 'dirid' directory
1914 * in a 'tree_id' tree. and sets path name to 'name'.
1915 */
1916 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1917 u64 tree_id, u64 dirid, char *name)
1918 {
1919 struct btrfs_root *root;
1920 struct btrfs_key key;
1921 char *ptr;
1922 int ret = -1;
1923 int slot;
1924 int len;
1925 int total_len = 0;
1926 struct btrfs_inode_ref *iref;
1927 struct extent_buffer *l;
1928 struct btrfs_path *path;
1929
1930 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1931 name[0]='\0';
1932 return 0;
1933 }
1934
1935 path = btrfs_alloc_path();
1936 if (!path)
1937 return -ENOMEM;
1938
1939 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1940
1941 key.objectid = tree_id;
1942 key.type = BTRFS_ROOT_ITEM_KEY;
1943 key.offset = (u64)-1;
1944 root = btrfs_read_fs_root_no_name(info, &key);
1945 if (IS_ERR(root)) {
1946 printk(KERN_ERR "could not find root %llu\n", tree_id);
1947 ret = -ENOENT;
1948 goto out;
1949 }
1950
1951 key.objectid = dirid;
1952 key.type = BTRFS_INODE_REF_KEY;
1953 key.offset = (u64)-1;
1954
1955 while(1) {
1956 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1957 if (ret < 0)
1958 goto out;
1959
1960 l = path->nodes[0];
1961 slot = path->slots[0];
1962 if (ret > 0 && slot > 0)
1963 slot--;
1964 btrfs_item_key_to_cpu(l, &key, slot);
1965
1966 if (ret > 0 && (key.objectid != dirid ||
1967 key.type != BTRFS_INODE_REF_KEY)) {
1968 ret = -ENOENT;
1969 goto out;
1970 }
1971
1972 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1973 len = btrfs_inode_ref_name_len(l, iref);
1974 ptr -= len + 1;
1975 total_len += len + 1;
1976 if (ptr < name)
1977 goto out;
1978
1979 *(ptr + len) = '/';
1980 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1981
1982 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1983 break;
1984
1985 btrfs_release_path(path);
1986 key.objectid = key.offset;
1987 key.offset = (u64)-1;
1988 dirid = key.objectid;
1989 }
1990 if (ptr < name)
1991 goto out;
1992 memmove(name, ptr, total_len);
1993 name[total_len]='\0';
1994 ret = 0;
1995 out:
1996 btrfs_free_path(path);
1997 return ret;
1998 }
1999
2000 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2001 void __user *argp)
2002 {
2003 struct btrfs_ioctl_ino_lookup_args *args;
2004 struct inode *inode;
2005 int ret;
2006
2007 if (!capable(CAP_SYS_ADMIN))
2008 return -EPERM;
2009
2010 args = memdup_user(argp, sizeof(*args));
2011 if (IS_ERR(args))
2012 return PTR_ERR(args);
2013
2014 inode = fdentry(file)->d_inode;
2015
2016 if (args->treeid == 0)
2017 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2018
2019 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2020 args->treeid, args->objectid,
2021 args->name);
2022
2023 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2024 ret = -EFAULT;
2025
2026 kfree(args);
2027 return ret;
2028 }
2029
2030 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2031 void __user *arg)
2032 {
2033 struct dentry *parent = fdentry(file);
2034 struct dentry *dentry;
2035 struct inode *dir = parent->d_inode;
2036 struct inode *inode;
2037 struct btrfs_root *root = BTRFS_I(dir)->root;
2038 struct btrfs_root *dest = NULL;
2039 struct btrfs_ioctl_vol_args *vol_args;
2040 struct btrfs_trans_handle *trans;
2041 int namelen;
2042 int ret;
2043 int err = 0;
2044
2045 vol_args = memdup_user(arg, sizeof(*vol_args));
2046 if (IS_ERR(vol_args))
2047 return PTR_ERR(vol_args);
2048
2049 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2050 namelen = strlen(vol_args->name);
2051 if (strchr(vol_args->name, '/') ||
2052 strncmp(vol_args->name, "..", namelen) == 0) {
2053 err = -EINVAL;
2054 goto out;
2055 }
2056
2057 err = mnt_want_write_file(file);
2058 if (err)
2059 goto out;
2060
2061 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
2062 dentry = lookup_one_len(vol_args->name, parent, namelen);
2063 if (IS_ERR(dentry)) {
2064 err = PTR_ERR(dentry);
2065 goto out_unlock_dir;
2066 }
2067
2068 if (!dentry->d_inode) {
2069 err = -ENOENT;
2070 goto out_dput;
2071 }
2072
2073 inode = dentry->d_inode;
2074 dest = BTRFS_I(inode)->root;
2075 if (!capable(CAP_SYS_ADMIN)){
2076 /*
2077 * Regular user. Only allow this with a special mount
2078 * option, when the user has write+exec access to the
2079 * subvol root, and when rmdir(2) would have been
2080 * allowed.
2081 *
2082 * Note that this is _not_ check that the subvol is
2083 * empty or doesn't contain data that we wouldn't
2084 * otherwise be able to delete.
2085 *
2086 * Users who want to delete empty subvols should try
2087 * rmdir(2).
2088 */
2089 err = -EPERM;
2090 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2091 goto out_dput;
2092
2093 /*
2094 * Do not allow deletion if the parent dir is the same
2095 * as the dir to be deleted. That means the ioctl
2096 * must be called on the dentry referencing the root
2097 * of the subvol, not a random directory contained
2098 * within it.
2099 */
2100 err = -EINVAL;
2101 if (root == dest)
2102 goto out_dput;
2103
2104 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2105 if (err)
2106 goto out_dput;
2107 }
2108
2109 /* check if subvolume may be deleted by a user */
2110 err = btrfs_may_delete(dir, dentry, 1);
2111 if (err)
2112 goto out_dput;
2113
2114 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2115 err = -EINVAL;
2116 goto out_dput;
2117 }
2118
2119 mutex_lock(&inode->i_mutex);
2120 err = d_invalidate(dentry);
2121 if (err)
2122 goto out_unlock;
2123
2124 down_write(&root->fs_info->subvol_sem);
2125
2126 err = may_destroy_subvol(dest);
2127 if (err)
2128 goto out_up_write;
2129
2130 trans = btrfs_start_transaction(root, 0);
2131 if (IS_ERR(trans)) {
2132 err = PTR_ERR(trans);
2133 goto out_up_write;
2134 }
2135 trans->block_rsv = &root->fs_info->global_block_rsv;
2136
2137 ret = btrfs_unlink_subvol(trans, root, dir,
2138 dest->root_key.objectid,
2139 dentry->d_name.name,
2140 dentry->d_name.len);
2141 if (ret) {
2142 err = ret;
2143 btrfs_abort_transaction(trans, root, ret);
2144 goto out_end_trans;
2145 }
2146
2147 btrfs_record_root_in_trans(trans, dest);
2148
2149 memset(&dest->root_item.drop_progress, 0,
2150 sizeof(dest->root_item.drop_progress));
2151 dest->root_item.drop_level = 0;
2152 btrfs_set_root_refs(&dest->root_item, 0);
2153
2154 if (!xchg(&dest->orphan_item_inserted, 1)) {
2155 ret = btrfs_insert_orphan_item(trans,
2156 root->fs_info->tree_root,
2157 dest->root_key.objectid);
2158 if (ret) {
2159 btrfs_abort_transaction(trans, root, ret);
2160 err = ret;
2161 goto out_end_trans;
2162 }
2163 }
2164 out_end_trans:
2165 ret = btrfs_end_transaction(trans, root);
2166 if (ret && !err)
2167 err = ret;
2168 inode->i_flags |= S_DEAD;
2169 out_up_write:
2170 up_write(&root->fs_info->subvol_sem);
2171 out_unlock:
2172 mutex_unlock(&inode->i_mutex);
2173 if (!err) {
2174 shrink_dcache_sb(root->fs_info->sb);
2175 btrfs_invalidate_inodes(dest);
2176 d_delete(dentry);
2177
2178 /* the last ref */
2179 if (dest->cache_inode) {
2180 iput(dest->cache_inode);
2181 dest->cache_inode = NULL;
2182 }
2183 }
2184 out_dput:
2185 dput(dentry);
2186 out_unlock_dir:
2187 mutex_unlock(&dir->i_mutex);
2188 mnt_drop_write_file(file);
2189 out:
2190 kfree(vol_args);
2191 return err;
2192 }
2193
2194 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2195 {
2196 struct inode *inode = fdentry(file)->d_inode;
2197 struct btrfs_root *root = BTRFS_I(inode)->root;
2198 struct btrfs_ioctl_defrag_range_args *range;
2199 int ret;
2200
2201 ret = mnt_want_write_file(file);
2202 if (ret)
2203 return ret;
2204
2205 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2206 1)) {
2207 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
2208 mnt_drop_write_file(file);
2209 return -EINVAL;
2210 }
2211
2212 if (btrfs_root_readonly(root)) {
2213 ret = -EROFS;
2214 goto out;
2215 }
2216
2217 switch (inode->i_mode & S_IFMT) {
2218 case S_IFDIR:
2219 if (!capable(CAP_SYS_ADMIN)) {
2220 ret = -EPERM;
2221 goto out;
2222 }
2223 ret = btrfs_defrag_root(root);
2224 if (ret)
2225 goto out;
2226 ret = btrfs_defrag_root(root->fs_info->extent_root);
2227 break;
2228 case S_IFREG:
2229 if (!(file->f_mode & FMODE_WRITE)) {
2230 ret = -EINVAL;
2231 goto out;
2232 }
2233
2234 range = kzalloc(sizeof(*range), GFP_KERNEL);
2235 if (!range) {
2236 ret = -ENOMEM;
2237 goto out;
2238 }
2239
2240 if (argp) {
2241 if (copy_from_user(range, argp,
2242 sizeof(*range))) {
2243 ret = -EFAULT;
2244 kfree(range);
2245 goto out;
2246 }
2247 /* compression requires us to start the IO */
2248 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2249 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2250 range->extent_thresh = (u32)-1;
2251 }
2252 } else {
2253 /* the rest are all set to zero by kzalloc */
2254 range->len = (u64)-1;
2255 }
2256 ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
2257 range, 0, 0);
2258 if (ret > 0)
2259 ret = 0;
2260 kfree(range);
2261 break;
2262 default:
2263 ret = -EINVAL;
2264 }
2265 out:
2266 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2267 mnt_drop_write_file(file);
2268 return ret;
2269 }
2270
2271 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2272 {
2273 struct btrfs_ioctl_vol_args *vol_args;
2274 int ret;
2275
2276 if (!capable(CAP_SYS_ADMIN))
2277 return -EPERM;
2278
2279 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2280 1)) {
2281 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
2282 return -EINVAL;
2283 }
2284
2285 mutex_lock(&root->fs_info->volume_mutex);
2286 vol_args = memdup_user(arg, sizeof(*vol_args));
2287 if (IS_ERR(vol_args)) {
2288 ret = PTR_ERR(vol_args);
2289 goto out;
2290 }
2291
2292 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2293 ret = btrfs_init_new_device(root, vol_args->name);
2294
2295 kfree(vol_args);
2296 out:
2297 mutex_unlock(&root->fs_info->volume_mutex);
2298 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2299 return ret;
2300 }
2301
2302 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2303 {
2304 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2305 struct btrfs_ioctl_vol_args *vol_args;
2306 int ret;
2307
2308 if (!capable(CAP_SYS_ADMIN))
2309 return -EPERM;
2310
2311 ret = mnt_want_write_file(file);
2312 if (ret)
2313 return ret;
2314
2315 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2316 1)) {
2317 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
2318 mnt_drop_write_file(file);
2319 return -EINVAL;
2320 }
2321
2322 mutex_lock(&root->fs_info->volume_mutex);
2323 vol_args = memdup_user(arg, sizeof(*vol_args));
2324 if (IS_ERR(vol_args)) {
2325 ret = PTR_ERR(vol_args);
2326 goto out;
2327 }
2328
2329 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2330 ret = btrfs_rm_device(root, vol_args->name);
2331
2332 kfree(vol_args);
2333 out:
2334 mutex_unlock(&root->fs_info->volume_mutex);
2335 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2336 mnt_drop_write_file(file);
2337 return ret;
2338 }
2339
2340 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2341 {
2342 struct btrfs_ioctl_fs_info_args *fi_args;
2343 struct btrfs_device *device;
2344 struct btrfs_device *next;
2345 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2346 int ret = 0;
2347
2348 if (!capable(CAP_SYS_ADMIN))
2349 return -EPERM;
2350
2351 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2352 if (!fi_args)
2353 return -ENOMEM;
2354
2355 fi_args->num_devices = fs_devices->num_devices;
2356 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2357
2358 mutex_lock(&fs_devices->device_list_mutex);
2359 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2360 if (device->devid > fi_args->max_id)
2361 fi_args->max_id = device->devid;
2362 }
2363 mutex_unlock(&fs_devices->device_list_mutex);
2364
2365 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2366 ret = -EFAULT;
2367
2368 kfree(fi_args);
2369 return ret;
2370 }
2371
2372 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2373 {
2374 struct btrfs_ioctl_dev_info_args *di_args;
2375 struct btrfs_device *dev;
2376 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2377 int ret = 0;
2378 char *s_uuid = NULL;
2379 char empty_uuid[BTRFS_UUID_SIZE] = {0};
2380
2381 if (!capable(CAP_SYS_ADMIN))
2382 return -EPERM;
2383
2384 di_args = memdup_user(arg, sizeof(*di_args));
2385 if (IS_ERR(di_args))
2386 return PTR_ERR(di_args);
2387
2388 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2389 s_uuid = di_args->uuid;
2390
2391 mutex_lock(&fs_devices->device_list_mutex);
2392 dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2393 mutex_unlock(&fs_devices->device_list_mutex);
2394
2395 if (!dev) {
2396 ret = -ENODEV;
2397 goto out;
2398 }
2399
2400 di_args->devid = dev->devid;
2401 di_args->bytes_used = dev->bytes_used;
2402 di_args->total_bytes = dev->total_bytes;
2403 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2404 if (dev->name) {
2405 struct rcu_string *name;
2406
2407 rcu_read_lock();
2408 name = rcu_dereference(dev->name);
2409 strncpy(di_args->path, name->str, sizeof(di_args->path));
2410 rcu_read_unlock();
2411 di_args->path[sizeof(di_args->path) - 1] = 0;
2412 } else {
2413 di_args->path[0] = '\0';
2414 }
2415
2416 out:
2417 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2418 ret = -EFAULT;
2419
2420 kfree(di_args);
2421 return ret;
2422 }
2423
2424 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2425 u64 off, u64 olen, u64 destoff)
2426 {
2427 struct inode *inode = fdentry(file)->d_inode;
2428 struct btrfs_root *root = BTRFS_I(inode)->root;
2429 struct fd src_file;
2430 struct inode *src;
2431 struct btrfs_trans_handle *trans;
2432 struct btrfs_path *path;
2433 struct extent_buffer *leaf;
2434 char *buf;
2435 struct btrfs_key key;
2436 u32 nritems;
2437 int slot;
2438 int ret;
2439 u64 len = olen;
2440 u64 bs = root->fs_info->sb->s_blocksize;
2441
2442 /*
2443 * TODO:
2444 * - split compressed inline extents. annoying: we need to
2445 * decompress into destination's address_space (the file offset
2446 * may change, so source mapping won't do), then recompress (or
2447 * otherwise reinsert) a subrange.
2448 * - allow ranges within the same file to be cloned (provided
2449 * they don't overlap)?
2450 */
2451
2452 /* the destination must be opened for writing */
2453 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2454 return -EINVAL;
2455
2456 if (btrfs_root_readonly(root))
2457 return -EROFS;
2458
2459 ret = mnt_want_write_file(file);
2460 if (ret)
2461 return ret;
2462
2463 src_file = fdget(srcfd);
2464 if (!src_file.file) {
2465 ret = -EBADF;
2466 goto out_drop_write;
2467 }
2468
2469 ret = -EXDEV;
2470 if (src_file.file->f_path.mnt != file->f_path.mnt)
2471 goto out_fput;
2472
2473 src = src_file.file->f_dentry->d_inode;
2474
2475 ret = -EINVAL;
2476 if (src == inode)
2477 goto out_fput;
2478
2479 /* the src must be open for reading */
2480 if (!(src_file.file->f_mode & FMODE_READ))
2481 goto out_fput;
2482
2483 /* don't make the dst file partly checksummed */
2484 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2485 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2486 goto out_fput;
2487
2488 ret = -EISDIR;
2489 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2490 goto out_fput;
2491
2492 ret = -EXDEV;
2493 if (src->i_sb != inode->i_sb)
2494 goto out_fput;
2495
2496 ret = -ENOMEM;
2497 buf = vmalloc(btrfs_level_size(root, 0));
2498 if (!buf)
2499 goto out_fput;
2500
2501 path = btrfs_alloc_path();
2502 if (!path) {
2503 vfree(buf);
2504 goto out_fput;
2505 }
2506 path->reada = 2;
2507
2508 if (inode < src) {
2509 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2510 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2511 } else {
2512 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2513 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2514 }
2515
2516 /* determine range to clone */
2517 ret = -EINVAL;
2518 if (off + len > src->i_size || off + len < off)
2519 goto out_unlock;
2520 if (len == 0)
2521 olen = len = src->i_size - off;
2522 /* if we extend to eof, continue to block boundary */
2523 if (off + len == src->i_size)
2524 len = ALIGN(src->i_size, bs) - off;
2525
2526 /* verify the end result is block aligned */
2527 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2528 !IS_ALIGNED(destoff, bs))
2529 goto out_unlock;
2530
2531 if (destoff > inode->i_size) {
2532 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2533 if (ret)
2534 goto out_unlock;
2535 }
2536
2537 /* truncate page cache pages from target inode range */
2538 truncate_inode_pages_range(&inode->i_data, destoff,
2539 PAGE_CACHE_ALIGN(destoff + len) - 1);
2540
2541 /* do any pending delalloc/csum calc on src, one way or
2542 another, and lock file content */
2543 while (1) {
2544 struct btrfs_ordered_extent *ordered;
2545 lock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
2546 ordered = btrfs_lookup_first_ordered_extent(src, off + len - 1);
2547 if (!ordered &&
2548 !test_range_bit(&BTRFS_I(src)->io_tree, off, off + len - 1,
2549 EXTENT_DELALLOC, 0, NULL))
2550 break;
2551 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
2552 if (ordered)
2553 btrfs_put_ordered_extent(ordered);
2554 btrfs_wait_ordered_range(src, off, len);
2555 }
2556
2557 /* clone data */
2558 key.objectid = btrfs_ino(src);
2559 key.type = BTRFS_EXTENT_DATA_KEY;
2560 key.offset = 0;
2561
2562 while (1) {
2563 /*
2564 * note the key will change type as we walk through the
2565 * tree.
2566 */
2567 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
2568 0, 0);
2569 if (ret < 0)
2570 goto out;
2571
2572 nritems = btrfs_header_nritems(path->nodes[0]);
2573 if (path->slots[0] >= nritems) {
2574 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
2575 if (ret < 0)
2576 goto out;
2577 if (ret > 0)
2578 break;
2579 nritems = btrfs_header_nritems(path->nodes[0]);
2580 }
2581 leaf = path->nodes[0];
2582 slot = path->slots[0];
2583
2584 btrfs_item_key_to_cpu(leaf, &key, slot);
2585 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2586 key.objectid != btrfs_ino(src))
2587 break;
2588
2589 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2590 struct btrfs_file_extent_item *extent;
2591 int type;
2592 u32 size;
2593 struct btrfs_key new_key;
2594 u64 disko = 0, diskl = 0;
2595 u64 datao = 0, datal = 0;
2596 u8 comp;
2597 u64 endoff;
2598
2599 size = btrfs_item_size_nr(leaf, slot);
2600 read_extent_buffer(leaf, buf,
2601 btrfs_item_ptr_offset(leaf, slot),
2602 size);
2603
2604 extent = btrfs_item_ptr(leaf, slot,
2605 struct btrfs_file_extent_item);
2606 comp = btrfs_file_extent_compression(leaf, extent);
2607 type = btrfs_file_extent_type(leaf, extent);
2608 if (type == BTRFS_FILE_EXTENT_REG ||
2609 type == BTRFS_FILE_EXTENT_PREALLOC) {
2610 disko = btrfs_file_extent_disk_bytenr(leaf,
2611 extent);
2612 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2613 extent);
2614 datao = btrfs_file_extent_offset(leaf, extent);
2615 datal = btrfs_file_extent_num_bytes(leaf,
2616 extent);
2617 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2618 /* take upper bound, may be compressed */
2619 datal = btrfs_file_extent_ram_bytes(leaf,
2620 extent);
2621 }
2622 btrfs_release_path(path);
2623
2624 if (key.offset + datal <= off ||
2625 key.offset >= off + len - 1)
2626 goto next;
2627
2628 memcpy(&new_key, &key, sizeof(new_key));
2629 new_key.objectid = btrfs_ino(inode);
2630 if (off <= key.offset)
2631 new_key.offset = key.offset + destoff - off;
2632 else
2633 new_key.offset = destoff;
2634
2635 /*
2636 * 1 - adjusting old extent (we may have to split it)
2637 * 1 - add new extent
2638 * 1 - inode update
2639 */
2640 trans = btrfs_start_transaction(root, 3);
2641 if (IS_ERR(trans)) {
2642 ret = PTR_ERR(trans);
2643 goto out;
2644 }
2645
2646 if (type == BTRFS_FILE_EXTENT_REG ||
2647 type == BTRFS_FILE_EXTENT_PREALLOC) {
2648 /*
2649 * a | --- range to clone ---| b
2650 * | ------------- extent ------------- |
2651 */
2652
2653 /* substract range b */
2654 if (key.offset + datal > off + len)
2655 datal = off + len - key.offset;
2656
2657 /* substract range a */
2658 if (off > key.offset) {
2659 datao += off - key.offset;
2660 datal -= off - key.offset;
2661 }
2662
2663 ret = btrfs_drop_extents(trans, root, inode,
2664 new_key.offset,
2665 new_key.offset + datal,
2666 1);
2667 if (ret) {
2668 btrfs_abort_transaction(trans, root,
2669 ret);
2670 btrfs_end_transaction(trans, root);
2671 goto out;
2672 }
2673
2674 ret = btrfs_insert_empty_item(trans, root, path,
2675 &new_key, size);
2676 if (ret) {
2677 btrfs_abort_transaction(trans, root,
2678 ret);
2679 btrfs_end_transaction(trans, root);
2680 goto out;
2681 }
2682
2683 leaf = path->nodes[0];
2684 slot = path->slots[0];
2685 write_extent_buffer(leaf, buf,
2686 btrfs_item_ptr_offset(leaf, slot),
2687 size);
2688
2689 extent = btrfs_item_ptr(leaf, slot,
2690 struct btrfs_file_extent_item);
2691
2692 /* disko == 0 means it's a hole */
2693 if (!disko)
2694 datao = 0;
2695
2696 btrfs_set_file_extent_offset(leaf, extent,
2697 datao);
2698 btrfs_set_file_extent_num_bytes(leaf, extent,
2699 datal);
2700 if (disko) {
2701 inode_add_bytes(inode, datal);
2702 ret = btrfs_inc_extent_ref(trans, root,
2703 disko, diskl, 0,
2704 root->root_key.objectid,
2705 btrfs_ino(inode),
2706 new_key.offset - datao,
2707 0);
2708 if (ret) {
2709 btrfs_abort_transaction(trans,
2710 root,
2711 ret);
2712 btrfs_end_transaction(trans,
2713 root);
2714 goto out;
2715
2716 }
2717 }
2718 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2719 u64 skip = 0;
2720 u64 trim = 0;
2721 if (off > key.offset) {
2722 skip = off - key.offset;
2723 new_key.offset += skip;
2724 }
2725
2726 if (key.offset + datal > off + len)
2727 trim = key.offset + datal - (off + len);
2728
2729 if (comp && (skip || trim)) {
2730 ret = -EINVAL;
2731 btrfs_end_transaction(trans, root);
2732 goto out;
2733 }
2734 size -= skip + trim;
2735 datal -= skip + trim;
2736
2737 ret = btrfs_drop_extents(trans, root, inode,
2738 new_key.offset,
2739 new_key.offset + datal,
2740 1);
2741 if (ret) {
2742 btrfs_abort_transaction(trans, root,
2743 ret);
2744 btrfs_end_transaction(trans, root);
2745 goto out;
2746 }
2747
2748 ret = btrfs_insert_empty_item(trans, root, path,
2749 &new_key, size);
2750 if (ret) {
2751 btrfs_abort_transaction(trans, root,
2752 ret);
2753 btrfs_end_transaction(trans, root);
2754 goto out;
2755 }
2756
2757 if (skip) {
2758 u32 start =
2759 btrfs_file_extent_calc_inline_size(0);
2760 memmove(buf+start, buf+start+skip,
2761 datal);
2762 }
2763
2764 leaf = path->nodes[0];
2765 slot = path->slots[0];
2766 write_extent_buffer(leaf, buf,
2767 btrfs_item_ptr_offset(leaf, slot),
2768 size);
2769 inode_add_bytes(inode, datal);
2770 }
2771
2772 btrfs_mark_buffer_dirty(leaf);
2773 btrfs_release_path(path);
2774
2775 inode_inc_iversion(inode);
2776 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2777
2778 /*
2779 * we round up to the block size at eof when
2780 * determining which extents to clone above,
2781 * but shouldn't round up the file size
2782 */
2783 endoff = new_key.offset + datal;
2784 if (endoff > destoff+olen)
2785 endoff = destoff+olen;
2786 if (endoff > inode->i_size)
2787 btrfs_i_size_write(inode, endoff);
2788
2789 ret = btrfs_update_inode(trans, root, inode);
2790 if (ret) {
2791 btrfs_abort_transaction(trans, root, ret);
2792 btrfs_end_transaction(trans, root);
2793 goto out;
2794 }
2795 ret = btrfs_end_transaction(trans, root);
2796 }
2797 next:
2798 btrfs_release_path(path);
2799 key.offset++;
2800 }
2801 ret = 0;
2802 out:
2803 btrfs_release_path(path);
2804 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
2805 out_unlock:
2806 mutex_unlock(&src->i_mutex);
2807 mutex_unlock(&inode->i_mutex);
2808 vfree(buf);
2809 btrfs_free_path(path);
2810 out_fput:
2811 fdput(src_file);
2812 out_drop_write:
2813 mnt_drop_write_file(file);
2814 return ret;
2815 }
2816
2817 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2818 {
2819 struct btrfs_ioctl_clone_range_args args;
2820
2821 if (copy_from_user(&args, argp, sizeof(args)))
2822 return -EFAULT;
2823 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2824 args.src_length, args.dest_offset);
2825 }
2826
2827 /*
2828 * there are many ways the trans_start and trans_end ioctls can lead
2829 * to deadlocks. They should only be used by applications that
2830 * basically own the machine, and have a very in depth understanding
2831 * of all the possible deadlocks and enospc problems.
2832 */
2833 static long btrfs_ioctl_trans_start(struct file *file)
2834 {
2835 struct inode *inode = fdentry(file)->d_inode;
2836 struct btrfs_root *root = BTRFS_I(inode)->root;
2837 struct btrfs_trans_handle *trans;
2838 int ret;
2839
2840 ret = -EPERM;
2841 if (!capable(CAP_SYS_ADMIN))
2842 goto out;
2843
2844 ret = -EINPROGRESS;
2845 if (file->private_data)
2846 goto out;
2847
2848 ret = -EROFS;
2849 if (btrfs_root_readonly(root))
2850 goto out;
2851
2852 ret = mnt_want_write_file(file);
2853 if (ret)
2854 goto out;
2855
2856 atomic_inc(&root->fs_info->open_ioctl_trans);
2857
2858 ret = -ENOMEM;
2859 trans = btrfs_start_ioctl_transaction(root);
2860 if (IS_ERR(trans))
2861 goto out_drop;
2862
2863 file->private_data = trans;
2864 return 0;
2865
2866 out_drop:
2867 atomic_dec(&root->fs_info->open_ioctl_trans);
2868 mnt_drop_write_file(file);
2869 out:
2870 return ret;
2871 }
2872
2873 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2874 {
2875 struct inode *inode = fdentry(file)->d_inode;
2876 struct btrfs_root *root = BTRFS_I(inode)->root;
2877 struct btrfs_root *new_root;
2878 struct btrfs_dir_item *di;
2879 struct btrfs_trans_handle *trans;
2880 struct btrfs_path *path;
2881 struct btrfs_key location;
2882 struct btrfs_disk_key disk_key;
2883 u64 objectid = 0;
2884 u64 dir_id;
2885 int ret;
2886
2887 if (!capable(CAP_SYS_ADMIN))
2888 return -EPERM;
2889
2890 ret = mnt_want_write_file(file);
2891 if (ret)
2892 return ret;
2893
2894 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
2895 ret = -EFAULT;
2896 goto out;
2897 }
2898
2899 if (!objectid)
2900 objectid = root->root_key.objectid;
2901
2902 location.objectid = objectid;
2903 location.type = BTRFS_ROOT_ITEM_KEY;
2904 location.offset = (u64)-1;
2905
2906 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2907 if (IS_ERR(new_root)) {
2908 ret = PTR_ERR(new_root);
2909 goto out;
2910 }
2911
2912 if (btrfs_root_refs(&new_root->root_item) == 0) {
2913 ret = -ENOENT;
2914 goto out;
2915 }
2916
2917 path = btrfs_alloc_path();
2918 if (!path) {
2919 ret = -ENOMEM;
2920 goto out;
2921 }
2922 path->leave_spinning = 1;
2923
2924 trans = btrfs_start_transaction(root, 1);
2925 if (IS_ERR(trans)) {
2926 btrfs_free_path(path);
2927 ret = PTR_ERR(trans);
2928 goto out;
2929 }
2930
2931 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
2932 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2933 dir_id, "default", 7, 1);
2934 if (IS_ERR_OR_NULL(di)) {
2935 btrfs_free_path(path);
2936 btrfs_end_transaction(trans, root);
2937 printk(KERN_ERR "Umm, you don't have the default dir item, "
2938 "this isn't going to work\n");
2939 ret = -ENOENT;
2940 goto out;
2941 }
2942
2943 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2944 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2945 btrfs_mark_buffer_dirty(path->nodes[0]);
2946 btrfs_free_path(path);
2947
2948 btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
2949 btrfs_end_transaction(trans, root);
2950 out:
2951 mnt_drop_write_file(file);
2952 return ret;
2953 }
2954
2955 void btrfs_get_block_group_info(struct list_head *groups_list,
2956 struct btrfs_ioctl_space_info *space)
2957 {
2958 struct btrfs_block_group_cache *block_group;
2959
2960 space->total_bytes = 0;
2961 space->used_bytes = 0;
2962 space->flags = 0;
2963 list_for_each_entry(block_group, groups_list, list) {
2964 space->flags = block_group->flags;
2965 space->total_bytes += block_group->key.offset;
2966 space->used_bytes +=
2967 btrfs_block_group_used(&block_group->item);
2968 }
2969 }
2970
2971 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
2972 {
2973 struct btrfs_ioctl_space_args space_args;
2974 struct btrfs_ioctl_space_info space;
2975 struct btrfs_ioctl_space_info *dest;
2976 struct btrfs_ioctl_space_info *dest_orig;
2977 struct btrfs_ioctl_space_info __user *user_dest;
2978 struct btrfs_space_info *info;
2979 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2980 BTRFS_BLOCK_GROUP_SYSTEM,
2981 BTRFS_BLOCK_GROUP_METADATA,
2982 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
2983 int num_types = 4;
2984 int alloc_size;
2985 int ret = 0;
2986 u64 slot_count = 0;
2987 int i, c;
2988
2989 if (copy_from_user(&space_args,
2990 (struct btrfs_ioctl_space_args __user *)arg,
2991 sizeof(space_args)))
2992 return -EFAULT;
2993
2994 for (i = 0; i < num_types; i++) {
2995 struct btrfs_space_info *tmp;
2996
2997 info = NULL;
2998 rcu_read_lock();
2999 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3000 list) {
3001 if (tmp->flags == types[i]) {
3002 info = tmp;
3003 break;
3004 }
3005 }
3006 rcu_read_unlock();
3007
3008 if (!info)
3009 continue;
3010
3011 down_read(&info->groups_sem);
3012 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3013 if (!list_empty(&info->block_groups[c]))
3014 slot_count++;
3015 }
3016 up_read(&info->groups_sem);
3017 }
3018
3019 /* space_slots == 0 means they are asking for a count */
3020 if (space_args.space_slots == 0) {
3021 space_args.total_spaces = slot_count;
3022 goto out;
3023 }
3024
3025 slot_count = min_t(u64, space_args.space_slots, slot_count);
3026
3027 alloc_size = sizeof(*dest) * slot_count;
3028
3029 /* we generally have at most 6 or so space infos, one for each raid
3030 * level. So, a whole page should be more than enough for everyone
3031 */
3032 if (alloc_size > PAGE_CACHE_SIZE)
3033 return -ENOMEM;
3034
3035 space_args.total_spaces = 0;
3036 dest = kmalloc(alloc_size, GFP_NOFS);
3037 if (!dest)
3038 return -ENOMEM;
3039 dest_orig = dest;
3040
3041 /* now we have a buffer to copy into */
3042 for (i = 0; i < num_types; i++) {
3043 struct btrfs_space_info *tmp;
3044
3045 if (!slot_count)
3046 break;
3047
3048 info = NULL;
3049 rcu_read_lock();
3050 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3051 list) {
3052 if (tmp->flags == types[i]) {
3053 info = tmp;
3054 break;
3055 }
3056 }
3057 rcu_read_unlock();
3058
3059 if (!info)
3060 continue;
3061 down_read(&info->groups_sem);
3062 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3063 if (!list_empty(&info->block_groups[c])) {
3064 btrfs_get_block_group_info(
3065 &info->block_groups[c], &space);
3066 memcpy(dest, &space, sizeof(space));
3067 dest++;
3068 space_args.total_spaces++;
3069 slot_count--;
3070 }
3071 if (!slot_count)
3072 break;
3073 }
3074 up_read(&info->groups_sem);
3075 }
3076
3077 user_dest = (struct btrfs_ioctl_space_info __user *)
3078 (arg + sizeof(struct btrfs_ioctl_space_args));
3079
3080 if (copy_to_user(user_dest, dest_orig, alloc_size))
3081 ret = -EFAULT;
3082
3083 kfree(dest_orig);
3084 out:
3085 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
3086 ret = -EFAULT;
3087
3088 return ret;
3089 }
3090
3091 /*
3092 * there are many ways the trans_start and trans_end ioctls can lead
3093 * to deadlocks. They should only be used by applications that
3094 * basically own the machine, and have a very in depth understanding
3095 * of all the possible deadlocks and enospc problems.
3096 */
3097 long btrfs_ioctl_trans_end(struct file *file)
3098 {
3099 struct inode *inode = fdentry(file)->d_inode;
3100 struct btrfs_root *root = BTRFS_I(inode)->root;
3101 struct btrfs_trans_handle *trans;
3102
3103 trans = file->private_data;
3104 if (!trans)
3105 return -EINVAL;
3106 file->private_data = NULL;
3107
3108 btrfs_end_transaction(trans, root);
3109
3110 atomic_dec(&root->fs_info->open_ioctl_trans);
3111
3112 mnt_drop_write_file(file);
3113 return 0;
3114 }
3115
3116 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
3117 void __user *argp)
3118 {
3119 struct btrfs_trans_handle *trans;
3120 u64 transid;
3121 int ret;
3122
3123 trans = btrfs_attach_transaction_barrier(root);
3124 if (IS_ERR(trans)) {
3125 if (PTR_ERR(trans) != -ENOENT)
3126 return PTR_ERR(trans);
3127
3128 /* No running transaction, don't bother */
3129 transid = root->fs_info->last_trans_committed;
3130 goto out;
3131 }
3132 transid = trans->transid;
3133 ret = btrfs_commit_transaction_async(trans, root, 0);
3134 if (ret) {
3135 btrfs_end_transaction(trans, root);
3136 return ret;
3137 }
3138 out:
3139 if (argp)
3140 if (copy_to_user(argp, &transid, sizeof(transid)))
3141 return -EFAULT;
3142 return 0;
3143 }
3144
3145 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
3146 void __user *argp)
3147 {
3148 u64 transid;
3149
3150 if (argp) {
3151 if (copy_from_user(&transid, argp, sizeof(transid)))
3152 return -EFAULT;
3153 } else {
3154 transid = 0; /* current trans */
3155 }
3156 return btrfs_wait_for_commit(root, transid);
3157 }
3158
3159 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
3160 {
3161 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3162 struct btrfs_ioctl_scrub_args *sa;
3163 int ret;
3164
3165 if (!capable(CAP_SYS_ADMIN))
3166 return -EPERM;
3167
3168 sa = memdup_user(arg, sizeof(*sa));
3169 if (IS_ERR(sa))
3170 return PTR_ERR(sa);
3171
3172 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
3173 ret = mnt_want_write_file(file);
3174 if (ret)
3175 goto out;
3176 }
3177
3178 ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
3179 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
3180 0);
3181
3182 if (copy_to_user(arg, sa, sizeof(*sa)))
3183 ret = -EFAULT;
3184
3185 if (!(sa->flags & BTRFS_SCRUB_READONLY))
3186 mnt_drop_write_file(file);
3187 out:
3188 kfree(sa);
3189 return ret;
3190 }
3191
3192 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
3193 {
3194 if (!capable(CAP_SYS_ADMIN))
3195 return -EPERM;
3196
3197 return btrfs_scrub_cancel(root->fs_info);
3198 }
3199
3200 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
3201 void __user *arg)
3202 {
3203 struct btrfs_ioctl_scrub_args *sa;
3204 int ret;
3205
3206 if (!capable(CAP_SYS_ADMIN))
3207 return -EPERM;
3208
3209 sa = memdup_user(arg, sizeof(*sa));
3210 if (IS_ERR(sa))
3211 return PTR_ERR(sa);
3212
3213 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
3214
3215 if (copy_to_user(arg, sa, sizeof(*sa)))
3216 ret = -EFAULT;
3217
3218 kfree(sa);
3219 return ret;
3220 }
3221
3222 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
3223 void __user *arg)
3224 {
3225 struct btrfs_ioctl_get_dev_stats *sa;
3226 int ret;
3227
3228 sa = memdup_user(arg, sizeof(*sa));
3229 if (IS_ERR(sa))
3230 return PTR_ERR(sa);
3231
3232 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3233 kfree(sa);
3234 return -EPERM;
3235 }
3236
3237 ret = btrfs_get_dev_stats(root, sa);
3238
3239 if (copy_to_user(arg, sa, sizeof(*sa)))
3240 ret = -EFAULT;
3241
3242 kfree(sa);
3243 return ret;
3244 }
3245
3246 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
3247 {
3248 struct btrfs_ioctl_dev_replace_args *p;
3249 int ret;
3250
3251 if (!capable(CAP_SYS_ADMIN))
3252 return -EPERM;
3253
3254 p = memdup_user(arg, sizeof(*p));
3255 if (IS_ERR(p))
3256 return PTR_ERR(p);
3257
3258 switch (p->cmd) {
3259 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3260 if (atomic_xchg(
3261 &root->fs_info->mutually_exclusive_operation_running,
3262 1)) {
3263 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
3264 ret = -EINPROGRESS;
3265 } else {
3266 ret = btrfs_dev_replace_start(root, p);
3267 atomic_set(
3268 &root->fs_info->mutually_exclusive_operation_running,
3269 0);
3270 }
3271 break;
3272 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
3273 btrfs_dev_replace_status(root->fs_info, p);
3274 ret = 0;
3275 break;
3276 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
3277 ret = btrfs_dev_replace_cancel(root->fs_info, p);
3278 break;
3279 default:
3280 ret = -EINVAL;
3281 break;
3282 }
3283
3284 if (copy_to_user(arg, p, sizeof(*p)))
3285 ret = -EFAULT;
3286
3287 kfree(p);
3288 return ret;
3289 }
3290
3291 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3292 {
3293 int ret = 0;
3294 int i;
3295 u64 rel_ptr;
3296 int size;
3297 struct btrfs_ioctl_ino_path_args *ipa = NULL;
3298 struct inode_fs_paths *ipath = NULL;
3299 struct btrfs_path *path;
3300
3301 if (!capable(CAP_DAC_READ_SEARCH))
3302 return -EPERM;
3303
3304 path = btrfs_alloc_path();
3305 if (!path) {
3306 ret = -ENOMEM;
3307 goto out;
3308 }
3309
3310 ipa = memdup_user(arg, sizeof(*ipa));
3311 if (IS_ERR(ipa)) {
3312 ret = PTR_ERR(ipa);
3313 ipa = NULL;
3314 goto out;
3315 }
3316
3317 size = min_t(u32, ipa->size, 4096);
3318 ipath = init_ipath(size, root, path);
3319 if (IS_ERR(ipath)) {
3320 ret = PTR_ERR(ipath);
3321 ipath = NULL;
3322 goto out;
3323 }
3324
3325 ret = paths_from_inode(ipa->inum, ipath);
3326 if (ret < 0)
3327 goto out;
3328
3329 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3330 rel_ptr = ipath->fspath->val[i] -
3331 (u64)(unsigned long)ipath->fspath->val;
3332 ipath->fspath->val[i] = rel_ptr;
3333 }
3334
3335 ret = copy_to_user((void *)(unsigned long)ipa->fspath,
3336 (void *)(unsigned long)ipath->fspath, size);
3337 if (ret) {
3338 ret = -EFAULT;
3339 goto out;
3340 }
3341
3342 out:
3343 btrfs_free_path(path);
3344 free_ipath(ipath);
3345 kfree(ipa);
3346
3347 return ret;
3348 }
3349
3350 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3351 {
3352 struct btrfs_data_container *inodes = ctx;
3353 const size_t c = 3 * sizeof(u64);
3354
3355 if (inodes->bytes_left >= c) {
3356 inodes->bytes_left -= c;
3357 inodes->val[inodes->elem_cnt] = inum;
3358 inodes->val[inodes->elem_cnt + 1] = offset;
3359 inodes->val[inodes->elem_cnt + 2] = root;
3360 inodes->elem_cnt += 3;
3361 } else {
3362 inodes->bytes_missing += c - inodes->bytes_left;
3363 inodes->bytes_left = 0;
3364 inodes->elem_missed += 3;
3365 }
3366
3367 return 0;
3368 }
3369
3370 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
3371 void __user *arg)
3372 {
3373 int ret = 0;
3374 int size;
3375 struct btrfs_ioctl_logical_ino_args *loi;
3376 struct btrfs_data_container *inodes = NULL;
3377 struct btrfs_path *path = NULL;
3378
3379 if (!capable(CAP_SYS_ADMIN))
3380 return -EPERM;
3381
3382 loi = memdup_user(arg, sizeof(*loi));
3383 if (IS_ERR(loi)) {
3384 ret = PTR_ERR(loi);
3385 loi = NULL;
3386 goto out;
3387 }
3388
3389 path = btrfs_alloc_path();
3390 if (!path) {
3391 ret = -ENOMEM;
3392 goto out;
3393 }
3394
3395 size = min_t(u32, loi->size, 64 * 1024);
3396 inodes = init_data_container(size);
3397 if (IS_ERR(inodes)) {
3398 ret = PTR_ERR(inodes);
3399 inodes = NULL;
3400 goto out;
3401 }
3402
3403 ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
3404 build_ino_list, inodes);
3405 if (ret == -EINVAL)
3406 ret = -ENOENT;
3407 if (ret < 0)
3408 goto out;
3409
3410 ret = copy_to_user((void *)(unsigned long)loi->inodes,
3411 (void *)(unsigned long)inodes, size);
3412 if (ret)
3413 ret = -EFAULT;
3414
3415 out:
3416 btrfs_free_path(path);
3417 vfree(inodes);
3418 kfree(loi);
3419
3420 return ret;
3421 }
3422
3423 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
3424 struct btrfs_ioctl_balance_args *bargs)
3425 {
3426 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3427
3428 bargs->flags = bctl->flags;
3429
3430 if (atomic_read(&fs_info->balance_running))
3431 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3432 if (atomic_read(&fs_info->balance_pause_req))
3433 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3434 if (atomic_read(&fs_info->balance_cancel_req))
3435 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3436
3437 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3438 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3439 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3440
3441 if (lock) {
3442 spin_lock(&fs_info->balance_lock);
3443 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3444 spin_unlock(&fs_info->balance_lock);
3445 } else {
3446 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3447 }
3448 }
3449
3450 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
3451 {
3452 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3453 struct btrfs_fs_info *fs_info = root->fs_info;
3454 struct btrfs_ioctl_balance_args *bargs;
3455 struct btrfs_balance_control *bctl;
3456 bool need_unlock; /* for mut. excl. ops lock */
3457 int ret;
3458
3459 if (!capable(CAP_SYS_ADMIN))
3460 return -EPERM;
3461
3462 ret = mnt_want_write_file(file);
3463 if (ret)
3464 return ret;
3465
3466 again:
3467 if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
3468 mutex_lock(&fs_info->volume_mutex);
3469 mutex_lock(&fs_info->balance_mutex);
3470 need_unlock = true;
3471 goto locked;
3472 }
3473
3474 /*
3475 * mut. excl. ops lock is locked. Three possibilites:
3476 * (1) some other op is running
3477 * (2) balance is running
3478 * (3) balance is paused -- special case (think resume)
3479 */
3480 mutex_lock(&fs_info->balance_mutex);
3481 if (fs_info->balance_ctl) {
3482 /* this is either (2) or (3) */
3483 if (!atomic_read(&fs_info->balance_running)) {
3484 mutex_unlock(&fs_info->balance_mutex);
3485 if (!mutex_trylock(&fs_info->volume_mutex))
3486 goto again;
3487 mutex_lock(&fs_info->balance_mutex);
3488
3489 if (fs_info->balance_ctl &&
3490 !atomic_read(&fs_info->balance_running)) {
3491 /* this is (3) */
3492 need_unlock = false;
3493 goto locked;
3494 }
3495
3496 mutex_unlock(&fs_info->balance_mutex);
3497 mutex_unlock(&fs_info->volume_mutex);
3498 goto again;
3499 } else {
3500 /* this is (2) */
3501 mutex_unlock(&fs_info->balance_mutex);
3502 ret = -EINPROGRESS;
3503 goto out;
3504 }
3505 } else {
3506 /* this is (1) */
3507 mutex_unlock(&fs_info->balance_mutex);
3508 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
3509 ret = -EINVAL;
3510 goto out;
3511 }
3512
3513 locked:
3514 BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
3515
3516 if (arg) {
3517 bargs = memdup_user(arg, sizeof(*bargs));
3518 if (IS_ERR(bargs)) {
3519 ret = PTR_ERR(bargs);
3520 goto out_unlock;
3521 }
3522
3523 if (bargs->flags & BTRFS_BALANCE_RESUME) {
3524 if (!fs_info->balance_ctl) {
3525 ret = -ENOTCONN;
3526 goto out_bargs;
3527 }
3528
3529 bctl = fs_info->balance_ctl;
3530 spin_lock(&fs_info->balance_lock);
3531 bctl->flags |= BTRFS_BALANCE_RESUME;
3532 spin_unlock(&fs_info->balance_lock);
3533
3534 goto do_balance;
3535 }
3536 } else {
3537 bargs = NULL;
3538 }
3539
3540 if (fs_info->balance_ctl) {
3541 ret = -EINPROGRESS;
3542 goto out_bargs;
3543 }
3544
3545 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3546 if (!bctl) {
3547 ret = -ENOMEM;
3548 goto out_bargs;
3549 }
3550
3551 bctl->fs_info = fs_info;
3552 if (arg) {
3553 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
3554 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
3555 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
3556
3557 bctl->flags = bargs->flags;
3558 } else {
3559 /* balance everything - no filters */
3560 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
3561 }
3562
3563 do_balance:
3564 /*
3565 * Ownership of bctl and mutually_exclusive_operation_running
3566 * goes to to btrfs_balance. bctl is freed in __cancel_balance,
3567 * or, if restriper was paused all the way until unmount, in
3568 * free_fs_info. mutually_exclusive_operation_running is
3569 * cleared in __cancel_balance.
3570 */
3571 need_unlock = false;
3572
3573 ret = btrfs_balance(bctl, bargs);
3574
3575 if (arg) {
3576 if (copy_to_user(arg, bargs, sizeof(*bargs)))
3577 ret = -EFAULT;
3578 }
3579
3580 out_bargs:
3581 kfree(bargs);
3582 out_unlock:
3583 mutex_unlock(&fs_info->balance_mutex);
3584 mutex_unlock(&fs_info->volume_mutex);
3585 if (need_unlock)
3586 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3587 out:
3588 mnt_drop_write_file(file);
3589 return ret;
3590 }
3591
3592 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
3593 {
3594 if (!capable(CAP_SYS_ADMIN))
3595 return -EPERM;
3596
3597 switch (cmd) {
3598 case BTRFS_BALANCE_CTL_PAUSE:
3599 return btrfs_pause_balance(root->fs_info);
3600 case BTRFS_BALANCE_CTL_CANCEL:
3601 return btrfs_cancel_balance(root->fs_info);
3602 }
3603
3604 return -EINVAL;
3605 }
3606
3607 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
3608 void __user *arg)
3609 {
3610 struct btrfs_fs_info *fs_info = root->fs_info;
3611 struct btrfs_ioctl_balance_args *bargs;
3612 int ret = 0;
3613
3614 if (!capable(CAP_SYS_ADMIN))
3615 return -EPERM;
3616
3617 mutex_lock(&fs_info->balance_mutex);
3618 if (!fs_info->balance_ctl) {
3619 ret = -ENOTCONN;
3620 goto out;
3621 }
3622
3623 bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
3624 if (!bargs) {
3625 ret = -ENOMEM;
3626 goto out;
3627 }
3628
3629 update_ioctl_balance_args(fs_info, 1, bargs);
3630
3631 if (copy_to_user(arg, bargs, sizeof(*bargs)))
3632 ret = -EFAULT;
3633
3634 kfree(bargs);
3635 out:
3636 mutex_unlock(&fs_info->balance_mutex);
3637 return ret;
3638 }
3639
3640 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
3641 {
3642 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3643 struct btrfs_ioctl_quota_ctl_args *sa;
3644 struct btrfs_trans_handle *trans = NULL;
3645 int ret;
3646 int err;
3647
3648 if (!capable(CAP_SYS_ADMIN))
3649 return -EPERM;
3650
3651 ret = mnt_want_write_file(file);
3652 if (ret)
3653 return ret;
3654
3655 sa = memdup_user(arg, sizeof(*sa));
3656 if (IS_ERR(sa)) {
3657 ret = PTR_ERR(sa);
3658 goto drop_write;
3659 }
3660
3661 if (sa->cmd != BTRFS_QUOTA_CTL_RESCAN) {
3662 trans = btrfs_start_transaction(root, 2);
3663 if (IS_ERR(trans)) {
3664 ret = PTR_ERR(trans);
3665 goto out;
3666 }
3667 }
3668
3669 switch (sa->cmd) {
3670 case BTRFS_QUOTA_CTL_ENABLE:
3671 ret = btrfs_quota_enable(trans, root->fs_info);
3672 break;
3673 case BTRFS_QUOTA_CTL_DISABLE:
3674 ret = btrfs_quota_disable(trans, root->fs_info);
3675 break;
3676 case BTRFS_QUOTA_CTL_RESCAN:
3677 ret = btrfs_quota_rescan(root->fs_info);
3678 break;
3679 default:
3680 ret = -EINVAL;
3681 break;
3682 }
3683
3684 if (copy_to_user(arg, sa, sizeof(*sa)))
3685 ret = -EFAULT;
3686
3687 if (trans) {
3688 err = btrfs_commit_transaction(trans, root);
3689 if (err && !ret)
3690 ret = err;
3691 }
3692 out:
3693 kfree(sa);
3694 drop_write:
3695 mnt_drop_write_file(file);
3696 return ret;
3697 }
3698
3699 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
3700 {
3701 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3702 struct btrfs_ioctl_qgroup_assign_args *sa;
3703 struct btrfs_trans_handle *trans;
3704 int ret;
3705 int err;
3706
3707 if (!capable(CAP_SYS_ADMIN))
3708 return -EPERM;
3709
3710 ret = mnt_want_write_file(file);
3711 if (ret)
3712 return ret;
3713
3714 sa = memdup_user(arg, sizeof(*sa));
3715 if (IS_ERR(sa)) {
3716 ret = PTR_ERR(sa);
3717 goto drop_write;
3718 }
3719
3720 trans = btrfs_join_transaction(root);
3721 if (IS_ERR(trans)) {
3722 ret = PTR_ERR(trans);
3723 goto out;
3724 }
3725
3726 /* FIXME: check if the IDs really exist */
3727 if (sa->assign) {
3728 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
3729 sa->src, sa->dst);
3730 } else {
3731 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
3732 sa->src, sa->dst);
3733 }
3734
3735 err = btrfs_end_transaction(trans, root);
3736 if (err && !ret)
3737 ret = err;
3738
3739 out:
3740 kfree(sa);
3741 drop_write:
3742 mnt_drop_write_file(file);
3743 return ret;
3744 }
3745
3746 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
3747 {
3748 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3749 struct btrfs_ioctl_qgroup_create_args *sa;
3750 struct btrfs_trans_handle *trans;
3751 int ret;
3752 int err;
3753
3754 if (!capable(CAP_SYS_ADMIN))
3755 return -EPERM;
3756
3757 ret = mnt_want_write_file(file);
3758 if (ret)
3759 return ret;
3760
3761 sa = memdup_user(arg, sizeof(*sa));
3762 if (IS_ERR(sa)) {
3763 ret = PTR_ERR(sa);
3764 goto drop_write;
3765 }
3766
3767 if (!sa->qgroupid) {
3768 ret = -EINVAL;
3769 goto out;
3770 }
3771
3772 trans = btrfs_join_transaction(root);
3773 if (IS_ERR(trans)) {
3774 ret = PTR_ERR(trans);
3775 goto out;
3776 }
3777
3778 /* FIXME: check if the IDs really exist */
3779 if (sa->create) {
3780 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
3781 NULL);
3782 } else {
3783 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
3784 }
3785
3786 err = btrfs_end_transaction(trans, root);
3787 if (err && !ret)
3788 ret = err;
3789
3790 out:
3791 kfree(sa);
3792 drop_write:
3793 mnt_drop_write_file(file);
3794 return ret;
3795 }
3796
3797 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
3798 {
3799 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3800 struct btrfs_ioctl_qgroup_limit_args *sa;
3801 struct btrfs_trans_handle *trans;
3802 int ret;
3803 int err;
3804 u64 qgroupid;
3805
3806 if (!capable(CAP_SYS_ADMIN))
3807 return -EPERM;
3808
3809 ret = mnt_want_write_file(file);
3810 if (ret)
3811 return ret;
3812
3813 sa = memdup_user(arg, sizeof(*sa));
3814 if (IS_ERR(sa)) {
3815 ret = PTR_ERR(sa);
3816 goto drop_write;
3817 }
3818
3819 trans = btrfs_join_transaction(root);
3820 if (IS_ERR(trans)) {
3821 ret = PTR_ERR(trans);
3822 goto out;
3823 }
3824
3825 qgroupid = sa->qgroupid;
3826 if (!qgroupid) {
3827 /* take the current subvol as qgroup */
3828 qgroupid = root->root_key.objectid;
3829 }
3830
3831 /* FIXME: check if the IDs really exist */
3832 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
3833
3834 err = btrfs_end_transaction(trans, root);
3835 if (err && !ret)
3836 ret = err;
3837
3838 out:
3839 kfree(sa);
3840 drop_write:
3841 mnt_drop_write_file(file);
3842 return ret;
3843 }
3844
3845 static long btrfs_ioctl_set_received_subvol(struct file *file,
3846 void __user *arg)
3847 {
3848 struct btrfs_ioctl_received_subvol_args *sa = NULL;
3849 struct inode *inode = fdentry(file)->d_inode;
3850 struct btrfs_root *root = BTRFS_I(inode)->root;
3851 struct btrfs_root_item *root_item = &root->root_item;
3852 struct btrfs_trans_handle *trans;
3853 struct timespec ct = CURRENT_TIME;
3854 int ret = 0;
3855
3856 ret = mnt_want_write_file(file);
3857 if (ret < 0)
3858 return ret;
3859
3860 down_write(&root->fs_info->subvol_sem);
3861
3862 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
3863 ret = -EINVAL;
3864 goto out;
3865 }
3866
3867 if (btrfs_root_readonly(root)) {
3868 ret = -EROFS;
3869 goto out;
3870 }
3871
3872 if (!inode_owner_or_capable(inode)) {
3873 ret = -EACCES;
3874 goto out;
3875 }
3876
3877 sa = memdup_user(arg, sizeof(*sa));
3878 if (IS_ERR(sa)) {
3879 ret = PTR_ERR(sa);
3880 sa = NULL;
3881 goto out;
3882 }
3883
3884 trans = btrfs_start_transaction(root, 1);
3885 if (IS_ERR(trans)) {
3886 ret = PTR_ERR(trans);
3887 trans = NULL;
3888 goto out;
3889 }
3890
3891 sa->rtransid = trans->transid;
3892 sa->rtime.sec = ct.tv_sec;
3893 sa->rtime.nsec = ct.tv_nsec;
3894
3895 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
3896 btrfs_set_root_stransid(root_item, sa->stransid);
3897 btrfs_set_root_rtransid(root_item, sa->rtransid);
3898 root_item->stime.sec = cpu_to_le64(sa->stime.sec);
3899 root_item->stime.nsec = cpu_to_le32(sa->stime.nsec);
3900 root_item->rtime.sec = cpu_to_le64(sa->rtime.sec);
3901 root_item->rtime.nsec = cpu_to_le32(sa->rtime.nsec);
3902
3903 ret = btrfs_update_root(trans, root->fs_info->tree_root,
3904 &root->root_key, &root->root_item);
3905 if (ret < 0) {
3906 btrfs_end_transaction(trans, root);
3907 trans = NULL;
3908 goto out;
3909 } else {
3910 ret = btrfs_commit_transaction(trans, root);
3911 if (ret < 0)
3912 goto out;
3913 }
3914
3915 ret = copy_to_user(arg, sa, sizeof(*sa));
3916 if (ret)
3917 ret = -EFAULT;
3918
3919 out:
3920 kfree(sa);
3921 up_write(&root->fs_info->subvol_sem);
3922 mnt_drop_write_file(file);
3923 return ret;
3924 }
3925
3926 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
3927 {
3928 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3929 const char *label = root->fs_info->super_copy->label;
3930 size_t len = strnlen(label, BTRFS_LABEL_SIZE);
3931 int ret;
3932
3933 if (len == BTRFS_LABEL_SIZE) {
3934 pr_warn("btrfs: label is too long, return the first %zu bytes\n",
3935 --len);
3936 }
3937
3938 mutex_lock(&root->fs_info->volume_mutex);
3939 ret = copy_to_user(arg, label, len);
3940 mutex_unlock(&root->fs_info->volume_mutex);
3941
3942 return ret ? -EFAULT : 0;
3943 }
3944
3945 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
3946 {
3947 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3948 struct btrfs_super_block *super_block = root->fs_info->super_copy;
3949 struct btrfs_trans_handle *trans;
3950 char label[BTRFS_LABEL_SIZE];
3951 int ret;
3952
3953 if (!capable(CAP_SYS_ADMIN))
3954 return -EPERM;
3955
3956 if (copy_from_user(label, arg, sizeof(label)))
3957 return -EFAULT;
3958
3959 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
3960 pr_err("btrfs: unable to set label with more than %d bytes\n",
3961 BTRFS_LABEL_SIZE - 1);
3962 return -EINVAL;
3963 }
3964
3965 ret = mnt_want_write_file(file);
3966 if (ret)
3967 return ret;
3968
3969 mutex_lock(&root->fs_info->volume_mutex);
3970 trans = btrfs_start_transaction(root, 0);
3971 if (IS_ERR(trans)) {
3972 ret = PTR_ERR(trans);
3973 goto out_unlock;
3974 }
3975
3976 strcpy(super_block->label, label);
3977 ret = btrfs_end_transaction(trans, root);
3978
3979 out_unlock:
3980 mutex_unlock(&root->fs_info->volume_mutex);
3981 mnt_drop_write_file(file);
3982 return ret;
3983 }
3984
3985 long btrfs_ioctl(struct file *file, unsigned int
3986 cmd, unsigned long arg)
3987 {
3988 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3989 void __user *argp = (void __user *)arg;
3990
3991 switch (cmd) {
3992 case FS_IOC_GETFLAGS:
3993 return btrfs_ioctl_getflags(file, argp);
3994 case FS_IOC_SETFLAGS:
3995 return btrfs_ioctl_setflags(file, argp);
3996 case FS_IOC_GETVERSION:
3997 return btrfs_ioctl_getversion(file, argp);
3998 case FITRIM:
3999 return btrfs_ioctl_fitrim(file, argp);
4000 case BTRFS_IOC_SNAP_CREATE:
4001 return btrfs_ioctl_snap_create(file, argp, 0);
4002 case BTRFS_IOC_SNAP_CREATE_V2:
4003 return btrfs_ioctl_snap_create_v2(file, argp, 0);
4004 case BTRFS_IOC_SUBVOL_CREATE:
4005 return btrfs_ioctl_snap_create(file, argp, 1);
4006 case BTRFS_IOC_SUBVOL_CREATE_V2:
4007 return btrfs_ioctl_snap_create_v2(file, argp, 1);
4008 case BTRFS_IOC_SNAP_DESTROY:
4009 return btrfs_ioctl_snap_destroy(file, argp);
4010 case BTRFS_IOC_SUBVOL_GETFLAGS:
4011 return btrfs_ioctl_subvol_getflags(file, argp);
4012 case BTRFS_IOC_SUBVOL_SETFLAGS:
4013 return btrfs_ioctl_subvol_setflags(file, argp);
4014 case BTRFS_IOC_DEFAULT_SUBVOL:
4015 return btrfs_ioctl_default_subvol(file, argp);
4016 case BTRFS_IOC_DEFRAG:
4017 return btrfs_ioctl_defrag(file, NULL);
4018 case BTRFS_IOC_DEFRAG_RANGE:
4019 return btrfs_ioctl_defrag(file, argp);
4020 case BTRFS_IOC_RESIZE:
4021 return btrfs_ioctl_resize(file, argp);
4022 case BTRFS_IOC_ADD_DEV:
4023 return btrfs_ioctl_add_dev(root, argp);
4024 case BTRFS_IOC_RM_DEV:
4025 return btrfs_ioctl_rm_dev(file, argp);
4026 case BTRFS_IOC_FS_INFO:
4027 return btrfs_ioctl_fs_info(root, argp);
4028 case BTRFS_IOC_DEV_INFO:
4029 return btrfs_ioctl_dev_info(root, argp);
4030 case BTRFS_IOC_BALANCE:
4031 return btrfs_ioctl_balance(file, NULL);
4032 case BTRFS_IOC_CLONE:
4033 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
4034 case BTRFS_IOC_CLONE_RANGE:
4035 return btrfs_ioctl_clone_range(file, argp);
4036 case BTRFS_IOC_TRANS_START:
4037 return btrfs_ioctl_trans_start(file);
4038 case BTRFS_IOC_TRANS_END:
4039 return btrfs_ioctl_trans_end(file);
4040 case BTRFS_IOC_TREE_SEARCH:
4041 return btrfs_ioctl_tree_search(file, argp);
4042 case BTRFS_IOC_INO_LOOKUP:
4043 return btrfs_ioctl_ino_lookup(file, argp);
4044 case BTRFS_IOC_INO_PATHS:
4045 return btrfs_ioctl_ino_to_path(root, argp);
4046 case BTRFS_IOC_LOGICAL_INO:
4047 return btrfs_ioctl_logical_to_ino(root, argp);
4048 case BTRFS_IOC_SPACE_INFO:
4049 return btrfs_ioctl_space_info(root, argp);
4050 case BTRFS_IOC_SYNC:
4051 btrfs_sync_fs(file->f_dentry->d_sb, 1);
4052 return 0;
4053 case BTRFS_IOC_START_SYNC:
4054 return btrfs_ioctl_start_sync(root, argp);
4055 case BTRFS_IOC_WAIT_SYNC:
4056 return btrfs_ioctl_wait_sync(root, argp);
4057 case BTRFS_IOC_SCRUB:
4058 return btrfs_ioctl_scrub(file, argp);
4059 case BTRFS_IOC_SCRUB_CANCEL:
4060 return btrfs_ioctl_scrub_cancel(root, argp);
4061 case BTRFS_IOC_SCRUB_PROGRESS:
4062 return btrfs_ioctl_scrub_progress(root, argp);
4063 case BTRFS_IOC_BALANCE_V2:
4064 return btrfs_ioctl_balance(file, argp);
4065 case BTRFS_IOC_BALANCE_CTL:
4066 return btrfs_ioctl_balance_ctl(root, arg);
4067 case BTRFS_IOC_BALANCE_PROGRESS:
4068 return btrfs_ioctl_balance_progress(root, argp);
4069 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
4070 return btrfs_ioctl_set_received_subvol(file, argp);
4071 case BTRFS_IOC_SEND:
4072 return btrfs_ioctl_send(file, argp);
4073 case BTRFS_IOC_GET_DEV_STATS:
4074 return btrfs_ioctl_get_dev_stats(root, argp);
4075 case BTRFS_IOC_QUOTA_CTL:
4076 return btrfs_ioctl_quota_ctl(file, argp);
4077 case BTRFS_IOC_QGROUP_ASSIGN:
4078 return btrfs_ioctl_qgroup_assign(file, argp);
4079 case BTRFS_IOC_QGROUP_CREATE:
4080 return btrfs_ioctl_qgroup_create(file, argp);
4081 case BTRFS_IOC_QGROUP_LIMIT:
4082 return btrfs_ioctl_qgroup_limit(file, argp);
4083 case BTRFS_IOC_DEV_REPLACE:
4084 return btrfs_ioctl_dev_replace(root, argp);
4085 case BTRFS_IOC_GET_FSLABEL:
4086 return btrfs_ioctl_get_fslabel(file, argp);
4087 case BTRFS_IOC_SET_FSLABEL:
4088 return btrfs_ioctl_set_fslabel(file, argp);
4089 }
4090
4091 return -ENOTTY;
4092 }
Linux kernel - Deliverables
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