?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Merge branch 'for-linus' of git://git.infradead.org/users/sameo/mfd-2.6
[linux-2.6/kvm.git] / fs / btrfs / ioctl.c
blob538f65a79ec5694eb16bd80567238eb320de0703
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 "compat.h"
45 #include "ctree.h"
46 #include "disk-io.h"
47 #include "transaction.h"
48 #include "btrfs_inode.h"
49 #include "ioctl.h"
50 #include "print-tree.h"
51 #include "volumes.h"
52 #include "locking.h"
53 #include "inode-map.h"
54
55 /* Mask out flags that are inappropriate for the given type of inode. */
56 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
57 {
58 if (S_ISDIR(mode))
59 return flags;
60 else if (S_ISREG(mode))
61 return flags & ~FS_DIRSYNC_FL;
62 else
63 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
64 }
65
66 /*
67 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
68 */
69 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
70 {
71 unsigned int iflags = 0;
72
73 if (flags & BTRFS_INODE_SYNC)
74 iflags |= FS_SYNC_FL;
75 if (flags & BTRFS_INODE_IMMUTABLE)
76 iflags |= FS_IMMUTABLE_FL;
77 if (flags & BTRFS_INODE_APPEND)
78 iflags |= FS_APPEND_FL;
79 if (flags & BTRFS_INODE_NODUMP)
80 iflags |= FS_NODUMP_FL;
81 if (flags & BTRFS_INODE_NOATIME)
82 iflags |= FS_NOATIME_FL;
83 if (flags & BTRFS_INODE_DIRSYNC)
84 iflags |= FS_DIRSYNC_FL;
85 if (flags & BTRFS_INODE_NODATACOW)
86 iflags |= FS_NOCOW_FL;
87
88 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
89 iflags |= FS_COMPR_FL;
90 else if (flags & BTRFS_INODE_NOCOMPRESS)
91 iflags |= FS_NOCOMP_FL;
92
93 return iflags;
94 }
95
96 /*
97 * Update inode->i_flags based on the btrfs internal flags.
98 */
99 void btrfs_update_iflags(struct inode *inode)
100 {
101 struct btrfs_inode *ip = BTRFS_I(inode);
102
103 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
104
105 if (ip->flags & BTRFS_INODE_SYNC)
106 inode->i_flags |= S_SYNC;
107 if (ip->flags & BTRFS_INODE_IMMUTABLE)
108 inode->i_flags |= S_IMMUTABLE;
109 if (ip->flags & BTRFS_INODE_APPEND)
110 inode->i_flags |= S_APPEND;
111 if (ip->flags & BTRFS_INODE_NOATIME)
112 inode->i_flags |= S_NOATIME;
113 if (ip->flags & BTRFS_INODE_DIRSYNC)
114 inode->i_flags |= S_DIRSYNC;
115 }
116
117 /*
118 * Inherit flags from the parent inode.
119 *
120 * Unlike extN we don't have any flags we don't want to inherit currently.
121 */
122 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
123 {
124 unsigned int flags;
125
126 if (!dir)
127 return;
128
129 flags = BTRFS_I(dir)->flags;
130
131 if (S_ISREG(inode->i_mode))
132 flags &= ~BTRFS_INODE_DIRSYNC;
133 else if (!S_ISDIR(inode->i_mode))
134 flags &= (BTRFS_INODE_NODUMP | BTRFS_INODE_NOATIME);
135
136 BTRFS_I(inode)->flags = flags;
137 btrfs_update_iflags(inode);
138 }
139
140 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
141 {
142 struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
143 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
144
145 if (copy_to_user(arg, &flags, sizeof(flags)))
146 return -EFAULT;
147 return 0;
148 }
149
150 static int check_flags(unsigned int flags)
151 {
152 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
153 FS_NOATIME_FL | FS_NODUMP_FL | \
154 FS_SYNC_FL | FS_DIRSYNC_FL | \
155 FS_NOCOMP_FL | FS_COMPR_FL |
156 FS_NOCOW_FL))
157 return -EOPNOTSUPP;
158
159 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
160 return -EINVAL;
161
162 return 0;
163 }
164
165 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
166 {
167 struct inode *inode = file->f_path.dentry->d_inode;
168 struct btrfs_inode *ip = BTRFS_I(inode);
169 struct btrfs_root *root = ip->root;
170 struct btrfs_trans_handle *trans;
171 unsigned int flags, oldflags;
172 int ret;
173
174 if (btrfs_root_readonly(root))
175 return -EROFS;
176
177 if (copy_from_user(&flags, arg, sizeof(flags)))
178 return -EFAULT;
179
180 ret = check_flags(flags);
181 if (ret)
182 return ret;
183
184 if (!inode_owner_or_capable(inode))
185 return -EACCES;
186
187 mutex_lock(&inode->i_mutex);
188
189 flags = btrfs_mask_flags(inode->i_mode, flags);
190 oldflags = btrfs_flags_to_ioctl(ip->flags);
191 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
192 if (!capable(CAP_LINUX_IMMUTABLE)) {
193 ret = -EPERM;
194 goto out_unlock;
195 }
196 }
197
198 ret = mnt_want_write(file->f_path.mnt);
199 if (ret)
200 goto out_unlock;
201
202 if (flags & FS_SYNC_FL)
203 ip->flags |= BTRFS_INODE_SYNC;
204 else
205 ip->flags &= ~BTRFS_INODE_SYNC;
206 if (flags & FS_IMMUTABLE_FL)
207 ip->flags |= BTRFS_INODE_IMMUTABLE;
208 else
209 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
210 if (flags & FS_APPEND_FL)
211 ip->flags |= BTRFS_INODE_APPEND;
212 else
213 ip->flags &= ~BTRFS_INODE_APPEND;
214 if (flags & FS_NODUMP_FL)
215 ip->flags |= BTRFS_INODE_NODUMP;
216 else
217 ip->flags &= ~BTRFS_INODE_NODUMP;
218 if (flags & FS_NOATIME_FL)
219 ip->flags |= BTRFS_INODE_NOATIME;
220 else
221 ip->flags &= ~BTRFS_INODE_NOATIME;
222 if (flags & FS_DIRSYNC_FL)
223 ip->flags |= BTRFS_INODE_DIRSYNC;
224 else
225 ip->flags &= ~BTRFS_INODE_DIRSYNC;
226 if (flags & FS_NOCOW_FL)
227 ip->flags |= BTRFS_INODE_NODATACOW;
228 else
229 ip->flags &= ~BTRFS_INODE_NODATACOW;
230
231 /*
232 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
233 * flag may be changed automatically if compression code won't make
234 * things smaller.
235 */
236 if (flags & FS_NOCOMP_FL) {
237 ip->flags &= ~BTRFS_INODE_COMPRESS;
238 ip->flags |= BTRFS_INODE_NOCOMPRESS;
239 } else if (flags & FS_COMPR_FL) {
240 ip->flags |= BTRFS_INODE_COMPRESS;
241 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
242 } else {
243 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
244 }
245
246 trans = btrfs_join_transaction(root);
247 BUG_ON(IS_ERR(trans));
248
249 ret = btrfs_update_inode(trans, root, inode);
250 BUG_ON(ret);
251
252 btrfs_update_iflags(inode);
253 inode->i_ctime = CURRENT_TIME;
254 btrfs_end_transaction(trans, root);
255
256 mnt_drop_write(file->f_path.mnt);
257
258 ret = 0;
259 out_unlock:
260 mutex_unlock(&inode->i_mutex);
261 return ret;
262 }
263
264 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
265 {
266 struct inode *inode = file->f_path.dentry->d_inode;
267
268 return put_user(inode->i_generation, arg);
269 }
270
271 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
272 {
273 struct btrfs_root *root = fdentry(file)->d_sb->s_fs_info;
274 struct btrfs_fs_info *fs_info = root->fs_info;
275 struct btrfs_device *device;
276 struct request_queue *q;
277 struct fstrim_range range;
278 u64 minlen = ULLONG_MAX;
279 u64 num_devices = 0;
280 int ret;
281
282 if (!capable(CAP_SYS_ADMIN))
283 return -EPERM;
284
285 rcu_read_lock();
286 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
287 dev_list) {
288 if (!device->bdev)
289 continue;
290 q = bdev_get_queue(device->bdev);
291 if (blk_queue_discard(q)) {
292 num_devices++;
293 minlen = min((u64)q->limits.discard_granularity,
294 minlen);
295 }
296 }
297 rcu_read_unlock();
298 if (!num_devices)
299 return -EOPNOTSUPP;
300
301 if (copy_from_user(&range, arg, sizeof(range)))
302 return -EFAULT;
303
304 range.minlen = max(range.minlen, minlen);
305 ret = btrfs_trim_fs(root, &range);
306 if (ret < 0)
307 return ret;
308
309 if (copy_to_user(arg, &range, sizeof(range)))
310 return -EFAULT;
311
312 return 0;
313 }
314
315 static noinline int create_subvol(struct btrfs_root *root,
316 struct dentry *dentry,
317 char *name, int namelen,
318 u64 *async_transid)
319 {
320 struct btrfs_trans_handle *trans;
321 struct btrfs_key key;
322 struct btrfs_root_item root_item;
323 struct btrfs_inode_item *inode_item;
324 struct extent_buffer *leaf;
325 struct btrfs_root *new_root;
326 struct dentry *parent = dentry->d_parent;
327 struct inode *dir;
328 int ret;
329 int err;
330 u64 objectid;
331 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
332 u64 index = 0;
333
334 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
335 if (ret)
336 return ret;
337
338 dir = parent->d_inode;
339
340 /*
341 * 1 - inode item
342 * 2 - refs
343 * 1 - root item
344 * 2 - dir items
345 */
346 trans = btrfs_start_transaction(root, 6);
347 if (IS_ERR(trans))
348 return PTR_ERR(trans);
349
350 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
351 0, objectid, NULL, 0, 0, 0);
352 if (IS_ERR(leaf)) {
353 ret = PTR_ERR(leaf);
354 goto fail;
355 }
356
357 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
358 btrfs_set_header_bytenr(leaf, leaf->start);
359 btrfs_set_header_generation(leaf, trans->transid);
360 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
361 btrfs_set_header_owner(leaf, objectid);
362
363 write_extent_buffer(leaf, root->fs_info->fsid,
364 (unsigned long)btrfs_header_fsid(leaf),
365 BTRFS_FSID_SIZE);
366 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
367 (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
368 BTRFS_UUID_SIZE);
369 btrfs_mark_buffer_dirty(leaf);
370
371 inode_item = &root_item.inode;
372 memset(inode_item, 0, sizeof(*inode_item));
373 inode_item->generation = cpu_to_le64(1);
374 inode_item->size = cpu_to_le64(3);
375 inode_item->nlink = cpu_to_le32(1);
376 inode_item->nbytes = cpu_to_le64(root->leafsize);
377 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
378
379 root_item.flags = 0;
380 root_item.byte_limit = 0;
381 inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
382
383 btrfs_set_root_bytenr(&root_item, leaf->start);
384 btrfs_set_root_generation(&root_item, trans->transid);
385 btrfs_set_root_level(&root_item, 0);
386 btrfs_set_root_refs(&root_item, 1);
387 btrfs_set_root_used(&root_item, leaf->len);
388 btrfs_set_root_last_snapshot(&root_item, 0);
389
390 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
391 root_item.drop_level = 0;
392
393 btrfs_tree_unlock(leaf);
394 free_extent_buffer(leaf);
395 leaf = NULL;
396
397 btrfs_set_root_dirid(&root_item, new_dirid);
398
399 key.objectid = objectid;
400 key.offset = 0;
401 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
402 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
403 &root_item);
404 if (ret)
405 goto fail;
406
407 key.offset = (u64)-1;
408 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
409 BUG_ON(IS_ERR(new_root));
410
411 btrfs_record_root_in_trans(trans, new_root);
412
413 ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
414 /*
415 * insert the directory item
416 */
417 ret = btrfs_set_inode_index(dir, &index);
418 BUG_ON(ret);
419
420 ret = btrfs_insert_dir_item(trans, root,
421 name, namelen, dir, &key,
422 BTRFS_FT_DIR, index);
423 if (ret)
424 goto fail;
425
426 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
427 ret = btrfs_update_inode(trans, root, dir);
428 BUG_ON(ret);
429
430 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
431 objectid, root->root_key.objectid,
432 btrfs_ino(dir), index, name, namelen);
433
434 BUG_ON(ret);
435
436 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
437 fail:
438 if (async_transid) {
439 *async_transid = trans->transid;
440 err = btrfs_commit_transaction_async(trans, root, 1);
441 } else {
442 err = btrfs_commit_transaction(trans, root);
443 }
444 if (err && !ret)
445 ret = err;
446 return ret;
447 }
448
449 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
450 char *name, int namelen, u64 *async_transid,
451 bool readonly)
452 {
453 struct inode *inode;
454 struct btrfs_pending_snapshot *pending_snapshot;
455 struct btrfs_trans_handle *trans;
456 int ret;
457
458 if (!root->ref_cows)
459 return -EINVAL;
460
461 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
462 if (!pending_snapshot)
463 return -ENOMEM;
464
465 btrfs_init_block_rsv(&pending_snapshot->block_rsv);
466 pending_snapshot->dentry = dentry;
467 pending_snapshot->root = root;
468 pending_snapshot->readonly = readonly;
469
470 trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
471 if (IS_ERR(trans)) {
472 ret = PTR_ERR(trans);
473 goto fail;
474 }
475
476 ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
477 BUG_ON(ret);
478
479 spin_lock(&root->fs_info->trans_lock);
480 list_add(&pending_snapshot->list,
481 &trans->transaction->pending_snapshots);
482 spin_unlock(&root->fs_info->trans_lock);
483 if (async_transid) {
484 *async_transid = trans->transid;
485 ret = btrfs_commit_transaction_async(trans,
486 root->fs_info->extent_root, 1);
487 } else {
488 ret = btrfs_commit_transaction(trans,
489 root->fs_info->extent_root);
490 }
491 BUG_ON(ret);
492
493 ret = pending_snapshot->error;
494 if (ret)
495 goto fail;
496
497 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
498 if (ret)
499 goto fail;
500
501 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
502 if (IS_ERR(inode)) {
503 ret = PTR_ERR(inode);
504 goto fail;
505 }
506 BUG_ON(!inode);
507 d_instantiate(dentry, inode);
508 ret = 0;
509 fail:
510 kfree(pending_snapshot);
511 return ret;
512 }
513
514 /* copy of check_sticky in fs/namei.c()
515 * It's inline, so penalty for filesystems that don't use sticky bit is
516 * minimal.
517 */
518 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
519 {
520 uid_t fsuid = current_fsuid();
521
522 if (!(dir->i_mode & S_ISVTX))
523 return 0;
524 if (inode->i_uid == fsuid)
525 return 0;
526 if (dir->i_uid == fsuid)
527 return 0;
528 return !capable(CAP_FOWNER);
529 }
530
531 /* copy of may_delete in fs/namei.c()
532 * Check whether we can remove a link victim from directory dir, check
533 * whether the type of victim is right.
534 * 1. We can't do it if dir is read-only (done in permission())
535 * 2. We should have write and exec permissions on dir
536 * 3. We can't remove anything from append-only dir
537 * 4. We can't do anything with immutable dir (done in permission())
538 * 5. If the sticky bit on dir is set we should either
539 * a. be owner of dir, or
540 * b. be owner of victim, or
541 * c. have CAP_FOWNER capability
542 * 6. If the victim is append-only or immutable we can't do antyhing with
543 * links pointing to it.
544 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
545 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
546 * 9. We can't remove a root or mountpoint.
547 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
548 * nfs_async_unlink().
549 */
550
551 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
552 {
553 int error;
554
555 if (!victim->d_inode)
556 return -ENOENT;
557
558 BUG_ON(victim->d_parent->d_inode != dir);
559 audit_inode_child(victim, dir);
560
561 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
562 if (error)
563 return error;
564 if (IS_APPEND(dir))
565 return -EPERM;
566 if (btrfs_check_sticky(dir, victim->d_inode)||
567 IS_APPEND(victim->d_inode)||
568 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
569 return -EPERM;
570 if (isdir) {
571 if (!S_ISDIR(victim->d_inode->i_mode))
572 return -ENOTDIR;
573 if (IS_ROOT(victim))
574 return -EBUSY;
575 } else if (S_ISDIR(victim->d_inode->i_mode))
576 return -EISDIR;
577 if (IS_DEADDIR(dir))
578 return -ENOENT;
579 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
580 return -EBUSY;
581 return 0;
582 }
583
584 /* copy of may_create in fs/namei.c() */
585 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
586 {
587 if (child->d_inode)
588 return -EEXIST;
589 if (IS_DEADDIR(dir))
590 return -ENOENT;
591 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
592 }
593
594 /*
595 * Create a new subvolume below @parent. This is largely modeled after
596 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
597 * inside this filesystem so it's quite a bit simpler.
598 */
599 static noinline int btrfs_mksubvol(struct path *parent,
600 char *name, int namelen,
601 struct btrfs_root *snap_src,
602 u64 *async_transid, bool readonly)
603 {
604 struct inode *dir = parent->dentry->d_inode;
605 struct dentry *dentry;
606 int error;
607
608 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
609
610 dentry = lookup_one_len(name, parent->dentry, namelen);
611 error = PTR_ERR(dentry);
612 if (IS_ERR(dentry))
613 goto out_unlock;
614
615 error = -EEXIST;
616 if (dentry->d_inode)
617 goto out_dput;
618
619 error = mnt_want_write(parent->mnt);
620 if (error)
621 goto out_dput;
622
623 error = btrfs_may_create(dir, dentry);
624 if (error)
625 goto out_drop_write;
626
627 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
628
629 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
630 goto out_up_read;
631
632 if (snap_src) {
633 error = create_snapshot(snap_src, dentry,
634 name, namelen, async_transid, readonly);
635 } else {
636 error = create_subvol(BTRFS_I(dir)->root, dentry,
637 name, namelen, async_transid);
638 }
639 if (!error)
640 fsnotify_mkdir(dir, dentry);
641 out_up_read:
642 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
643 out_drop_write:
644 mnt_drop_write(parent->mnt);
645 out_dput:
646 dput(dentry);
647 out_unlock:
648 mutex_unlock(&dir->i_mutex);
649 return error;
650 }
651
652 /*
653 * When we're defragging a range, we don't want to kick it off again
654 * if it is really just waiting for delalloc to send it down.
655 * If we find a nice big extent or delalloc range for the bytes in the
656 * file you want to defrag, we return 0 to let you know to skip this
657 * part of the file
658 */
659 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
660 {
661 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
662 struct extent_map *em = NULL;
663 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
664 u64 end;
665
666 read_lock(&em_tree->lock);
667 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
668 read_unlock(&em_tree->lock);
669
670 if (em) {
671 end = extent_map_end(em);
672 free_extent_map(em);
673 if (end - offset > thresh)
674 return 0;
675 }
676 /* if we already have a nice delalloc here, just stop */
677 thresh /= 2;
678 end = count_range_bits(io_tree, &offset, offset + thresh,
679 thresh, EXTENT_DELALLOC, 1);
680 if (end >= thresh)
681 return 0;
682 return 1;
683 }
684
685 /*
686 * helper function to walk through a file and find extents
687 * newer than a specific transid, and smaller than thresh.
688 *
689 * This is used by the defragging code to find new and small
690 * extents
691 */
692 static int find_new_extents(struct btrfs_root *root,
693 struct inode *inode, u64 newer_than,
694 u64 *off, int thresh)
695 {
696 struct btrfs_path *path;
697 struct btrfs_key min_key;
698 struct btrfs_key max_key;
699 struct extent_buffer *leaf;
700 struct btrfs_file_extent_item *extent;
701 int type;
702 int ret;
703 u64 ino = btrfs_ino(inode);
704
705 path = btrfs_alloc_path();
706 if (!path)
707 return -ENOMEM;
708
709 min_key.objectid = ino;
710 min_key.type = BTRFS_EXTENT_DATA_KEY;
711 min_key.offset = *off;
712
713 max_key.objectid = ino;
714 max_key.type = (u8)-1;
715 max_key.offset = (u64)-1;
716
717 path->keep_locks = 1;
718
719 while(1) {
720 ret = btrfs_search_forward(root, &min_key, &max_key,
721 path, 0, newer_than);
722 if (ret != 0)
723 goto none;
724 if (min_key.objectid != ino)
725 goto none;
726 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
727 goto none;
728
729 leaf = path->nodes[0];
730 extent = btrfs_item_ptr(leaf, path->slots[0],
731 struct btrfs_file_extent_item);
732
733 type = btrfs_file_extent_type(leaf, extent);
734 if (type == BTRFS_FILE_EXTENT_REG &&
735 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
736 check_defrag_in_cache(inode, min_key.offset, thresh)) {
737 *off = min_key.offset;
738 btrfs_free_path(path);
739 return 0;
740 }
741
742 if (min_key.offset == (u64)-1)
743 goto none;
744
745 min_key.offset++;
746 btrfs_release_path(path);
747 }
748 none:
749 btrfs_free_path(path);
750 return -ENOENT;
751 }
752
753 static int should_defrag_range(struct inode *inode, u64 start, u64 len,
754 int thresh, u64 *last_len, u64 *skip,
755 u64 *defrag_end)
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 int ret = 1;
761
762 /*
763 * make sure that once we start defragging and extent, we keep on
764 * defragging it
765 */
766 if (start < *defrag_end)
767 return 1;
768
769 *skip = 0;
770
771 /*
772 * hopefully we have this extent in the tree already, try without
773 * the full extent lock
774 */
775 read_lock(&em_tree->lock);
776 em = lookup_extent_mapping(em_tree, start, len);
777 read_unlock(&em_tree->lock);
778
779 if (!em) {
780 /* get the big lock and read metadata off disk */
781 lock_extent(io_tree, start, start + len - 1, GFP_NOFS);
782 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
783 unlock_extent(io_tree, start, start + len - 1, GFP_NOFS);
784
785 if (IS_ERR(em))
786 return 0;
787 }
788
789 /* this will cover holes, and inline extents */
790 if (em->block_start >= EXTENT_MAP_LAST_BYTE)
791 ret = 0;
792
793 /*
794 * we hit a real extent, if it is big don't bother defragging it again
795 */
796 if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
797 ret = 0;
798
799 /*
800 * last_len ends up being a counter of how many bytes we've defragged.
801 * every time we choose not to defrag an extent, we reset *last_len
802 * so that the next tiny extent will force a defrag.
803 *
804 * The end result of this is that tiny extents before a single big
805 * extent will force at least part of that big extent to be defragged.
806 */
807 if (ret) {
808 *last_len += len;
809 *defrag_end = extent_map_end(em);
810 } else {
811 *last_len = 0;
812 *skip = extent_map_end(em);
813 *defrag_end = 0;
814 }
815
816 free_extent_map(em);
817 return ret;
818 }
819
820 /*
821 * it doesn't do much good to defrag one or two pages
822 * at a time. This pulls in a nice chunk of pages
823 * to COW and defrag.
824 *
825 * It also makes sure the delalloc code has enough
826 * dirty data to avoid making new small extents as part
827 * of the defrag
828 *
829 * It's a good idea to start RA on this range
830 * before calling this.
831 */
832 static int cluster_pages_for_defrag(struct inode *inode,
833 struct page **pages,
834 unsigned long start_index,
835 int num_pages)
836 {
837 unsigned long file_end;
838 u64 isize = i_size_read(inode);
839 u64 page_start;
840 u64 page_end;
841 int ret;
842 int i;
843 int i_done;
844 struct btrfs_ordered_extent *ordered;
845 struct extent_state *cached_state = NULL;
846
847 if (isize == 0)
848 return 0;
849 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
850
851 ret = btrfs_delalloc_reserve_space(inode,
852 num_pages << PAGE_CACHE_SHIFT);
853 if (ret)
854 return ret;
855 again:
856 ret = 0;
857 i_done = 0;
858
859 /* step one, lock all the pages */
860 for (i = 0; i < num_pages; i++) {
861 struct page *page;
862 page = find_or_create_page(inode->i_mapping,
863 start_index + i, GFP_NOFS);
864 if (!page)
865 break;
866
867 if (!PageUptodate(page)) {
868 btrfs_readpage(NULL, page);
869 lock_page(page);
870 if (!PageUptodate(page)) {
871 unlock_page(page);
872 page_cache_release(page);
873 ret = -EIO;
874 break;
875 }
876 }
877 isize = i_size_read(inode);
878 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
879 if (!isize || page->index > file_end ||
880 page->mapping != inode->i_mapping) {
881 /* whoops, we blew past eof, skip this page */
882 unlock_page(page);
883 page_cache_release(page);
884 break;
885 }
886 pages[i] = page;
887 i_done++;
888 }
889 if (!i_done || ret)
890 goto out;
891
892 if (!(inode->i_sb->s_flags & MS_ACTIVE))
893 goto out;
894
895 /*
896 * so now we have a nice long stream of locked
897 * and up to date pages, lets wait on them
898 */
899 for (i = 0; i < i_done; i++)
900 wait_on_page_writeback(pages[i]);
901
902 page_start = page_offset(pages[0]);
903 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
904
905 lock_extent_bits(&BTRFS_I(inode)->io_tree,
906 page_start, page_end - 1, 0, &cached_state,
907 GFP_NOFS);
908 ordered = btrfs_lookup_first_ordered_extent(inode, page_end - 1);
909 if (ordered &&
910 ordered->file_offset + ordered->len > page_start &&
911 ordered->file_offset < page_end) {
912 btrfs_put_ordered_extent(ordered);
913 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
914 page_start, page_end - 1,
915 &cached_state, GFP_NOFS);
916 for (i = 0; i < i_done; i++) {
917 unlock_page(pages[i]);
918 page_cache_release(pages[i]);
919 }
920 btrfs_wait_ordered_range(inode, page_start,
921 page_end - page_start);
922 goto again;
923 }
924 if (ordered)
925 btrfs_put_ordered_extent(ordered);
926
927 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
928 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
929 EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
930 GFP_NOFS);
931
932 if (i_done != num_pages) {
933 spin_lock(&BTRFS_I(inode)->lock);
934 BTRFS_I(inode)->outstanding_extents++;
935 spin_unlock(&BTRFS_I(inode)->lock);
936 btrfs_delalloc_release_space(inode,
937 (num_pages - i_done) << PAGE_CACHE_SHIFT);
938 }
939
940
941 btrfs_set_extent_delalloc(inode, page_start, page_end - 1,
942 &cached_state);
943
944 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
945 page_start, page_end - 1, &cached_state,
946 GFP_NOFS);
947
948 for (i = 0; i < i_done; i++) {
949 clear_page_dirty_for_io(pages[i]);
950 ClearPageChecked(pages[i]);
951 set_page_extent_mapped(pages[i]);
952 set_page_dirty(pages[i]);
953 unlock_page(pages[i]);
954 page_cache_release(pages[i]);
955 }
956 return i_done;
957 out:
958 for (i = 0; i < i_done; i++) {
959 unlock_page(pages[i]);
960 page_cache_release(pages[i]);
961 }
962 btrfs_delalloc_release_space(inode, num_pages << PAGE_CACHE_SHIFT);
963 return ret;
964
965 }
966
967 int btrfs_defrag_file(struct inode *inode, struct file *file,
968 struct btrfs_ioctl_defrag_range_args *range,
969 u64 newer_than, unsigned long max_to_defrag)
970 {
971 struct btrfs_root *root = BTRFS_I(inode)->root;
972 struct btrfs_super_block *disk_super;
973 struct file_ra_state *ra = NULL;
974 unsigned long last_index;
975 u64 features;
976 u64 last_len = 0;
977 u64 skip = 0;
978 u64 defrag_end = 0;
979 u64 newer_off = range->start;
980 int newer_left = 0;
981 unsigned long i;
982 int ret;
983 int defrag_count = 0;
984 int compress_type = BTRFS_COMPRESS_ZLIB;
985 int extent_thresh = range->extent_thresh;
986 int newer_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
987 u64 new_align = ~((u64)128 * 1024 - 1);
988 struct page **pages = NULL;
989
990 if (extent_thresh == 0)
991 extent_thresh = 256 * 1024;
992
993 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
994 if (range->compress_type > BTRFS_COMPRESS_TYPES)
995 return -EINVAL;
996 if (range->compress_type)
997 compress_type = range->compress_type;
998 }
999
1000 if (inode->i_size == 0)
1001 return 0;
1002
1003 /*
1004 * if we were not given a file, allocate a readahead
1005 * context
1006 */
1007 if (!file) {
1008 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1009 if (!ra)
1010 return -ENOMEM;
1011 file_ra_state_init(ra, inode->i_mapping);
1012 } else {
1013 ra = &file->f_ra;
1014 }
1015
1016 pages = kmalloc(sizeof(struct page *) * newer_cluster,
1017 GFP_NOFS);
1018 if (!pages) {
1019 ret = -ENOMEM;
1020 goto out_ra;
1021 }
1022
1023 /* find the last page to defrag */
1024 if (range->start + range->len > range->start) {
1025 last_index = min_t(u64, inode->i_size - 1,
1026 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1027 } else {
1028 last_index = (inode->i_size - 1) >> PAGE_CACHE_SHIFT;
1029 }
1030
1031 if (newer_than) {
1032 ret = find_new_extents(root, inode, newer_than,
1033 &newer_off, 64 * 1024);
1034 if (!ret) {
1035 range->start = newer_off;
1036 /*
1037 * we always align our defrag to help keep
1038 * the extents in the file evenly spaced
1039 */
1040 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1041 newer_left = newer_cluster;
1042 } else
1043 goto out_ra;
1044 } else {
1045 i = range->start >> PAGE_CACHE_SHIFT;
1046 }
1047 if (!max_to_defrag)
1048 max_to_defrag = last_index - 1;
1049
1050 while (i <= last_index && defrag_count < max_to_defrag) {
1051 /*
1052 * make sure we stop running if someone unmounts
1053 * the FS
1054 */
1055 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1056 break;
1057
1058 if (!newer_than &&
1059 !should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1060 PAGE_CACHE_SIZE,
1061 extent_thresh,
1062 &last_len, &skip,
1063 &defrag_end)) {
1064 unsigned long next;
1065 /*
1066 * the should_defrag function tells us how much to skip
1067 * bump our counter by the suggested amount
1068 */
1069 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1070 i = max(i + 1, next);
1071 continue;
1072 }
1073 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1074 BTRFS_I(inode)->force_compress = compress_type;
1075
1076 btrfs_force_ra(inode->i_mapping, ra, file, i, newer_cluster);
1077
1078 ret = cluster_pages_for_defrag(inode, pages, i, newer_cluster);
1079 if (ret < 0)
1080 goto out_ra;
1081
1082 defrag_count += ret;
1083 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
1084 i += ret;
1085
1086 if (newer_than) {
1087 if (newer_off == (u64)-1)
1088 break;
1089
1090 newer_off = max(newer_off + 1,
1091 (u64)i << PAGE_CACHE_SHIFT);
1092
1093 ret = find_new_extents(root, inode,
1094 newer_than, &newer_off,
1095 64 * 1024);
1096 if (!ret) {
1097 range->start = newer_off;
1098 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1099 newer_left = newer_cluster;
1100 } else {
1101 break;
1102 }
1103 } else {
1104 i++;
1105 }
1106 }
1107
1108 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1109 filemap_flush(inode->i_mapping);
1110
1111 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1112 /* the filemap_flush will queue IO into the worker threads, but
1113 * we have to make sure the IO is actually started and that
1114 * ordered extents get created before we return
1115 */
1116 atomic_inc(&root->fs_info->async_submit_draining);
1117 while (atomic_read(&root->fs_info->nr_async_submits) ||
1118 atomic_read(&root->fs_info->async_delalloc_pages)) {
1119 wait_event(root->fs_info->async_submit_wait,
1120 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1121 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1122 }
1123 atomic_dec(&root->fs_info->async_submit_draining);
1124
1125 mutex_lock(&inode->i_mutex);
1126 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1127 mutex_unlock(&inode->i_mutex);
1128 }
1129
1130 disk_super = &root->fs_info->super_copy;
1131 features = btrfs_super_incompat_flags(disk_super);
1132 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1133 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
1134 btrfs_set_super_incompat_flags(disk_super, features);
1135 }
1136
1137 if (!file)
1138 kfree(ra);
1139 return defrag_count;
1140
1141 out_ra:
1142 if (!file)
1143 kfree(ra);
1144 kfree(pages);
1145 return ret;
1146 }
1147
1148 static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
1149 void __user *arg)
1150 {
1151 u64 new_size;
1152 u64 old_size;
1153 u64 devid = 1;
1154 struct btrfs_ioctl_vol_args *vol_args;
1155 struct btrfs_trans_handle *trans;
1156 struct btrfs_device *device = NULL;
1157 char *sizestr;
1158 char *devstr = NULL;
1159 int ret = 0;
1160 int mod = 0;
1161
1162 if (root->fs_info->sb->s_flags & MS_RDONLY)
1163 return -EROFS;
1164
1165 if (!capable(CAP_SYS_ADMIN))
1166 return -EPERM;
1167
1168 vol_args = memdup_user(arg, sizeof(*vol_args));
1169 if (IS_ERR(vol_args))
1170 return PTR_ERR(vol_args);
1171
1172 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1173
1174 mutex_lock(&root->fs_info->volume_mutex);
1175 sizestr = vol_args->name;
1176 devstr = strchr(sizestr, ':');
1177 if (devstr) {
1178 char *end;
1179 sizestr = devstr + 1;
1180 *devstr = '\0';
1181 devstr = vol_args->name;
1182 devid = simple_strtoull(devstr, &end, 10);
1183 printk(KERN_INFO "resizing devid %llu\n",
1184 (unsigned long long)devid);
1185 }
1186 device = btrfs_find_device(root, devid, NULL, NULL);
1187 if (!device) {
1188 printk(KERN_INFO "resizer unable to find device %llu\n",
1189 (unsigned long long)devid);
1190 ret = -EINVAL;
1191 goto out_unlock;
1192 }
1193 if (!strcmp(sizestr, "max"))
1194 new_size = device->bdev->bd_inode->i_size;
1195 else {
1196 if (sizestr[0] == '-') {
1197 mod = -1;
1198 sizestr++;
1199 } else if (sizestr[0] == '+') {
1200 mod = 1;
1201 sizestr++;
1202 }
1203 new_size = memparse(sizestr, NULL);
1204 if (new_size == 0) {
1205 ret = -EINVAL;
1206 goto out_unlock;
1207 }
1208 }
1209
1210 old_size = device->total_bytes;
1211
1212 if (mod < 0) {
1213 if (new_size > old_size) {
1214 ret = -EINVAL;
1215 goto out_unlock;
1216 }
1217 new_size = old_size - new_size;
1218 } else if (mod > 0) {
1219 new_size = old_size + new_size;
1220 }
1221
1222 if (new_size < 256 * 1024 * 1024) {
1223 ret = -EINVAL;
1224 goto out_unlock;
1225 }
1226 if (new_size > device->bdev->bd_inode->i_size) {
1227 ret = -EFBIG;
1228 goto out_unlock;
1229 }
1230
1231 do_div(new_size, root->sectorsize);
1232 new_size *= root->sectorsize;
1233
1234 printk(KERN_INFO "new size for %s is %llu\n",
1235 device->name, (unsigned long long)new_size);
1236
1237 if (new_size > old_size) {
1238 trans = btrfs_start_transaction(root, 0);
1239 if (IS_ERR(trans)) {
1240 ret = PTR_ERR(trans);
1241 goto out_unlock;
1242 }
1243 ret = btrfs_grow_device(trans, device, new_size);
1244 btrfs_commit_transaction(trans, root);
1245 } else {
1246 ret = btrfs_shrink_device(device, new_size);
1247 }
1248
1249 out_unlock:
1250 mutex_unlock(&root->fs_info->volume_mutex);
1251 kfree(vol_args);
1252 return ret;
1253 }
1254
1255 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1256 char *name,
1257 unsigned long fd,
1258 int subvol,
1259 u64 *transid,
1260 bool readonly)
1261 {
1262 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1263 struct file *src_file;
1264 int namelen;
1265 int ret = 0;
1266
1267 if (root->fs_info->sb->s_flags & MS_RDONLY)
1268 return -EROFS;
1269
1270 namelen = strlen(name);
1271 if (strchr(name, '/')) {
1272 ret = -EINVAL;
1273 goto out;
1274 }
1275
1276 if (subvol) {
1277 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1278 NULL, transid, readonly);
1279 } else {
1280 struct inode *src_inode;
1281 src_file = fget(fd);
1282 if (!src_file) {
1283 ret = -EINVAL;
1284 goto out;
1285 }
1286
1287 src_inode = src_file->f_path.dentry->d_inode;
1288 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1289 printk(KERN_INFO "btrfs: Snapshot src from "
1290 "another FS\n");
1291 ret = -EINVAL;
1292 fput(src_file);
1293 goto out;
1294 }
1295 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1296 BTRFS_I(src_inode)->root,
1297 transid, readonly);
1298 fput(src_file);
1299 }
1300 out:
1301 return ret;
1302 }
1303
1304 static noinline int btrfs_ioctl_snap_create(struct file *file,
1305 void __user *arg, int subvol)
1306 {
1307 struct btrfs_ioctl_vol_args *vol_args;
1308 int ret;
1309
1310 vol_args = memdup_user(arg, sizeof(*vol_args));
1311 if (IS_ERR(vol_args))
1312 return PTR_ERR(vol_args);
1313 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1314
1315 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1316 vol_args->fd, subvol,
1317 NULL, false);
1318
1319 kfree(vol_args);
1320 return ret;
1321 }
1322
1323 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1324 void __user *arg, int subvol)
1325 {
1326 struct btrfs_ioctl_vol_args_v2 *vol_args;
1327 int ret;
1328 u64 transid = 0;
1329 u64 *ptr = NULL;
1330 bool readonly = false;
1331
1332 vol_args = memdup_user(arg, sizeof(*vol_args));
1333 if (IS_ERR(vol_args))
1334 return PTR_ERR(vol_args);
1335 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1336
1337 if (vol_args->flags &
1338 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
1339 ret = -EOPNOTSUPP;
1340 goto out;
1341 }
1342
1343 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1344 ptr = &transid;
1345 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1346 readonly = true;
1347
1348 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1349 vol_args->fd, subvol,
1350 ptr, readonly);
1351
1352 if (ret == 0 && ptr &&
1353 copy_to_user(arg +
1354 offsetof(struct btrfs_ioctl_vol_args_v2,
1355 transid), ptr, sizeof(*ptr)))
1356 ret = -EFAULT;
1357 out:
1358 kfree(vol_args);
1359 return ret;
1360 }
1361
1362 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1363 void __user *arg)
1364 {
1365 struct inode *inode = fdentry(file)->d_inode;
1366 struct btrfs_root *root = BTRFS_I(inode)->root;
1367 int ret = 0;
1368 u64 flags = 0;
1369
1370 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1371 return -EINVAL;
1372
1373 down_read(&root->fs_info->subvol_sem);
1374 if (btrfs_root_readonly(root))
1375 flags |= BTRFS_SUBVOL_RDONLY;
1376 up_read(&root->fs_info->subvol_sem);
1377
1378 if (copy_to_user(arg, &flags, sizeof(flags)))
1379 ret = -EFAULT;
1380
1381 return ret;
1382 }
1383
1384 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1385 void __user *arg)
1386 {
1387 struct inode *inode = fdentry(file)->d_inode;
1388 struct btrfs_root *root = BTRFS_I(inode)->root;
1389 struct btrfs_trans_handle *trans;
1390 u64 root_flags;
1391 u64 flags;
1392 int ret = 0;
1393
1394 if (root->fs_info->sb->s_flags & MS_RDONLY)
1395 return -EROFS;
1396
1397 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1398 return -EINVAL;
1399
1400 if (copy_from_user(&flags, arg, sizeof(flags)))
1401 return -EFAULT;
1402
1403 if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
1404 return -EINVAL;
1405
1406 if (flags & ~BTRFS_SUBVOL_RDONLY)
1407 return -EOPNOTSUPP;
1408
1409 if (!inode_owner_or_capable(inode))
1410 return -EACCES;
1411
1412 down_write(&root->fs_info->subvol_sem);
1413
1414 /* nothing to do */
1415 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1416 goto out;
1417
1418 root_flags = btrfs_root_flags(&root->root_item);
1419 if (flags & BTRFS_SUBVOL_RDONLY)
1420 btrfs_set_root_flags(&root->root_item,
1421 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1422 else
1423 btrfs_set_root_flags(&root->root_item,
1424 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1425
1426 trans = btrfs_start_transaction(root, 1);
1427 if (IS_ERR(trans)) {
1428 ret = PTR_ERR(trans);
1429 goto out_reset;
1430 }
1431
1432 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1433 &root->root_key, &root->root_item);
1434
1435 btrfs_commit_transaction(trans, root);
1436 out_reset:
1437 if (ret)
1438 btrfs_set_root_flags(&root->root_item, root_flags);
1439 out:
1440 up_write(&root->fs_info->subvol_sem);
1441 return ret;
1442 }
1443
1444 /*
1445 * helper to check if the subvolume references other subvolumes
1446 */
1447 static noinline int may_destroy_subvol(struct btrfs_root *root)
1448 {
1449 struct btrfs_path *path;
1450 struct btrfs_key key;
1451 int ret;
1452
1453 path = btrfs_alloc_path();
1454 if (!path)
1455 return -ENOMEM;
1456
1457 key.objectid = root->root_key.objectid;
1458 key.type = BTRFS_ROOT_REF_KEY;
1459 key.offset = (u64)-1;
1460
1461 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1462 &key, path, 0, 0);
1463 if (ret < 0)
1464 goto out;
1465 BUG_ON(ret == 0);
1466
1467 ret = 0;
1468 if (path->slots[0] > 0) {
1469 path->slots[0]--;
1470 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1471 if (key.objectid == root->root_key.objectid &&
1472 key.type == BTRFS_ROOT_REF_KEY)
1473 ret = -ENOTEMPTY;
1474 }
1475 out:
1476 btrfs_free_path(path);
1477 return ret;
1478 }
1479
1480 static noinline int key_in_sk(struct btrfs_key *key,
1481 struct btrfs_ioctl_search_key *sk)
1482 {
1483 struct btrfs_key test;
1484 int ret;
1485
1486 test.objectid = sk->min_objectid;
1487 test.type = sk->min_type;
1488 test.offset = sk->min_offset;
1489
1490 ret = btrfs_comp_cpu_keys(key, &test);
1491 if (ret < 0)
1492 return 0;
1493
1494 test.objectid = sk->max_objectid;
1495 test.type = sk->max_type;
1496 test.offset = sk->max_offset;
1497
1498 ret = btrfs_comp_cpu_keys(key, &test);
1499 if (ret > 0)
1500 return 0;
1501 return 1;
1502 }
1503
1504 static noinline int copy_to_sk(struct btrfs_root *root,
1505 struct btrfs_path *path,
1506 struct btrfs_key *key,
1507 struct btrfs_ioctl_search_key *sk,
1508 char *buf,
1509 unsigned long *sk_offset,
1510 int *num_found)
1511 {
1512 u64 found_transid;
1513 struct extent_buffer *leaf;
1514 struct btrfs_ioctl_search_header sh;
1515 unsigned long item_off;
1516 unsigned long item_len;
1517 int nritems;
1518 int i;
1519 int slot;
1520 int ret = 0;
1521
1522 leaf = path->nodes[0];
1523 slot = path->slots[0];
1524 nritems = btrfs_header_nritems(leaf);
1525
1526 if (btrfs_header_generation(leaf) > sk->max_transid) {
1527 i = nritems;
1528 goto advance_key;
1529 }
1530 found_transid = btrfs_header_generation(leaf);
1531
1532 for (i = slot; i < nritems; i++) {
1533 item_off = btrfs_item_ptr_offset(leaf, i);
1534 item_len = btrfs_item_size_nr(leaf, i);
1535
1536 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1537 item_len = 0;
1538
1539 if (sizeof(sh) + item_len + *sk_offset >
1540 BTRFS_SEARCH_ARGS_BUFSIZE) {
1541 ret = 1;
1542 goto overflow;
1543 }
1544
1545 btrfs_item_key_to_cpu(leaf, key, i);
1546 if (!key_in_sk(key, sk))
1547 continue;
1548
1549 sh.objectid = key->objectid;
1550 sh.offset = key->offset;
1551 sh.type = key->type;
1552 sh.len = item_len;
1553 sh.transid = found_transid;
1554
1555 /* copy search result header */
1556 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1557 *sk_offset += sizeof(sh);
1558
1559 if (item_len) {
1560 char *p = buf + *sk_offset;
1561 /* copy the item */
1562 read_extent_buffer(leaf, p,
1563 item_off, item_len);
1564 *sk_offset += item_len;
1565 }
1566 (*num_found)++;
1567
1568 if (*num_found >= sk->nr_items)
1569 break;
1570 }
1571 advance_key:
1572 ret = 0;
1573 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1574 key->offset++;
1575 else if (key->type < (u8)-1 && key->type < sk->max_type) {
1576 key->offset = 0;
1577 key->type++;
1578 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1579 key->offset = 0;
1580 key->type = 0;
1581 key->objectid++;
1582 } else
1583 ret = 1;
1584 overflow:
1585 return ret;
1586 }
1587
1588 static noinline int search_ioctl(struct inode *inode,
1589 struct btrfs_ioctl_search_args *args)
1590 {
1591 struct btrfs_root *root;
1592 struct btrfs_key key;
1593 struct btrfs_key max_key;
1594 struct btrfs_path *path;
1595 struct btrfs_ioctl_search_key *sk = &args->key;
1596 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1597 int ret;
1598 int num_found = 0;
1599 unsigned long sk_offset = 0;
1600
1601 path = btrfs_alloc_path();
1602 if (!path)
1603 return -ENOMEM;
1604
1605 if (sk->tree_id == 0) {
1606 /* search the root of the inode that was passed */
1607 root = BTRFS_I(inode)->root;
1608 } else {
1609 key.objectid = sk->tree_id;
1610 key.type = BTRFS_ROOT_ITEM_KEY;
1611 key.offset = (u64)-1;
1612 root = btrfs_read_fs_root_no_name(info, &key);
1613 if (IS_ERR(root)) {
1614 printk(KERN_ERR "could not find root %llu\n",
1615 sk->tree_id);
1616 btrfs_free_path(path);
1617 return -ENOENT;
1618 }
1619 }
1620
1621 key.objectid = sk->min_objectid;
1622 key.type = sk->min_type;
1623 key.offset = sk->min_offset;
1624
1625 max_key.objectid = sk->max_objectid;
1626 max_key.type = sk->max_type;
1627 max_key.offset = sk->max_offset;
1628
1629 path->keep_locks = 1;
1630
1631 while(1) {
1632 ret = btrfs_search_forward(root, &key, &max_key, path, 0,
1633 sk->min_transid);
1634 if (ret != 0) {
1635 if (ret > 0)
1636 ret = 0;
1637 goto err;
1638 }
1639 ret = copy_to_sk(root, path, &key, sk, args->buf,
1640 &sk_offset, &num_found);
1641 btrfs_release_path(path);
1642 if (ret || num_found >= sk->nr_items)
1643 break;
1644
1645 }
1646 ret = 0;
1647 err:
1648 sk->nr_items = num_found;
1649 btrfs_free_path(path);
1650 return ret;
1651 }
1652
1653 static noinline int btrfs_ioctl_tree_search(struct file *file,
1654 void __user *argp)
1655 {
1656 struct btrfs_ioctl_search_args *args;
1657 struct inode *inode;
1658 int ret;
1659
1660 if (!capable(CAP_SYS_ADMIN))
1661 return -EPERM;
1662
1663 args = memdup_user(argp, sizeof(*args));
1664 if (IS_ERR(args))
1665 return PTR_ERR(args);
1666
1667 inode = fdentry(file)->d_inode;
1668 ret = search_ioctl(inode, args);
1669 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1670 ret = -EFAULT;
1671 kfree(args);
1672 return ret;
1673 }
1674
1675 /*
1676 * Search INODE_REFs to identify path name of 'dirid' directory
1677 * in a 'tree_id' tree. and sets path name to 'name'.
1678 */
1679 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1680 u64 tree_id, u64 dirid, char *name)
1681 {
1682 struct btrfs_root *root;
1683 struct btrfs_key key;
1684 char *ptr;
1685 int ret = -1;
1686 int slot;
1687 int len;
1688 int total_len = 0;
1689 struct btrfs_inode_ref *iref;
1690 struct extent_buffer *l;
1691 struct btrfs_path *path;
1692
1693 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1694 name[0]='\0';
1695 return 0;
1696 }
1697
1698 path = btrfs_alloc_path();
1699 if (!path)
1700 return -ENOMEM;
1701
1702 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1703
1704 key.objectid = tree_id;
1705 key.type = BTRFS_ROOT_ITEM_KEY;
1706 key.offset = (u64)-1;
1707 root = btrfs_read_fs_root_no_name(info, &key);
1708 if (IS_ERR(root)) {
1709 printk(KERN_ERR "could not find root %llu\n", tree_id);
1710 ret = -ENOENT;
1711 goto out;
1712 }
1713
1714 key.objectid = dirid;
1715 key.type = BTRFS_INODE_REF_KEY;
1716 key.offset = (u64)-1;
1717
1718 while(1) {
1719 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1720 if (ret < 0)
1721 goto out;
1722
1723 l = path->nodes[0];
1724 slot = path->slots[0];
1725 if (ret > 0 && slot > 0)
1726 slot--;
1727 btrfs_item_key_to_cpu(l, &key, slot);
1728
1729 if (ret > 0 && (key.objectid != dirid ||
1730 key.type != BTRFS_INODE_REF_KEY)) {
1731 ret = -ENOENT;
1732 goto out;
1733 }
1734
1735 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1736 len = btrfs_inode_ref_name_len(l, iref);
1737 ptr -= len + 1;
1738 total_len += len + 1;
1739 if (ptr < name)
1740 goto out;
1741
1742 *(ptr + len) = '/';
1743 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1744
1745 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1746 break;
1747
1748 btrfs_release_path(path);
1749 key.objectid = key.offset;
1750 key.offset = (u64)-1;
1751 dirid = key.objectid;
1752 }
1753 if (ptr < name)
1754 goto out;
1755 memmove(name, ptr, total_len);
1756 name[total_len]='\0';
1757 ret = 0;
1758 out:
1759 btrfs_free_path(path);
1760 return ret;
1761 }
1762
1763 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
1764 void __user *argp)
1765 {
1766 struct btrfs_ioctl_ino_lookup_args *args;
1767 struct inode *inode;
1768 int ret;
1769
1770 if (!capable(CAP_SYS_ADMIN))
1771 return -EPERM;
1772
1773 args = memdup_user(argp, sizeof(*args));
1774 if (IS_ERR(args))
1775 return PTR_ERR(args);
1776
1777 inode = fdentry(file)->d_inode;
1778
1779 if (args->treeid == 0)
1780 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
1781
1782 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
1783 args->treeid, args->objectid,
1784 args->name);
1785
1786 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1787 ret = -EFAULT;
1788
1789 kfree(args);
1790 return ret;
1791 }
1792
1793 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
1794 void __user *arg)
1795 {
1796 struct dentry *parent = fdentry(file);
1797 struct dentry *dentry;
1798 struct inode *dir = parent->d_inode;
1799 struct inode *inode;
1800 struct btrfs_root *root = BTRFS_I(dir)->root;
1801 struct btrfs_root *dest = NULL;
1802 struct btrfs_ioctl_vol_args *vol_args;
1803 struct btrfs_trans_handle *trans;
1804 int namelen;
1805 int ret;
1806 int err = 0;
1807
1808 vol_args = memdup_user(arg, sizeof(*vol_args));
1809 if (IS_ERR(vol_args))
1810 return PTR_ERR(vol_args);
1811
1812 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1813 namelen = strlen(vol_args->name);
1814 if (strchr(vol_args->name, '/') ||
1815 strncmp(vol_args->name, "..", namelen) == 0) {
1816 err = -EINVAL;
1817 goto out;
1818 }
1819
1820 err = mnt_want_write(file->f_path.mnt);
1821 if (err)
1822 goto out;
1823
1824 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
1825 dentry = lookup_one_len(vol_args->name, parent, namelen);
1826 if (IS_ERR(dentry)) {
1827 err = PTR_ERR(dentry);
1828 goto out_unlock_dir;
1829 }
1830
1831 if (!dentry->d_inode) {
1832 err = -ENOENT;
1833 goto out_dput;
1834 }
1835
1836 inode = dentry->d_inode;
1837 dest = BTRFS_I(inode)->root;
1838 if (!capable(CAP_SYS_ADMIN)){
1839 /*
1840 * Regular user. Only allow this with a special mount
1841 * option, when the user has write+exec access to the
1842 * subvol root, and when rmdir(2) would have been
1843 * allowed.
1844 *
1845 * Note that this is _not_ check that the subvol is
1846 * empty or doesn't contain data that we wouldn't
1847 * otherwise be able to delete.
1848 *
1849 * Users who want to delete empty subvols should try
1850 * rmdir(2).
1851 */
1852 err = -EPERM;
1853 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
1854 goto out_dput;
1855
1856 /*
1857 * Do not allow deletion if the parent dir is the same
1858 * as the dir to be deleted. That means the ioctl
1859 * must be called on the dentry referencing the root
1860 * of the subvol, not a random directory contained
1861 * within it.
1862 */
1863 err = -EINVAL;
1864 if (root == dest)
1865 goto out_dput;
1866
1867 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
1868 if (err)
1869 goto out_dput;
1870
1871 /* check if subvolume may be deleted by a non-root user */
1872 err = btrfs_may_delete(dir, dentry, 1);
1873 if (err)
1874 goto out_dput;
1875 }
1876
1877 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1878 err = -EINVAL;
1879 goto out_dput;
1880 }
1881
1882 mutex_lock(&inode->i_mutex);
1883 err = d_invalidate(dentry);
1884 if (err)
1885 goto out_unlock;
1886
1887 down_write(&root->fs_info->subvol_sem);
1888
1889 err = may_destroy_subvol(dest);
1890 if (err)
1891 goto out_up_write;
1892
1893 trans = btrfs_start_transaction(root, 0);
1894 if (IS_ERR(trans)) {
1895 err = PTR_ERR(trans);
1896 goto out_up_write;
1897 }
1898 trans->block_rsv = &root->fs_info->global_block_rsv;
1899
1900 ret = btrfs_unlink_subvol(trans, root, dir,
1901 dest->root_key.objectid,
1902 dentry->d_name.name,
1903 dentry->d_name.len);
1904 BUG_ON(ret);
1905
1906 btrfs_record_root_in_trans(trans, dest);
1907
1908 memset(&dest->root_item.drop_progress, 0,
1909 sizeof(dest->root_item.drop_progress));
1910 dest->root_item.drop_level = 0;
1911 btrfs_set_root_refs(&dest->root_item, 0);
1912
1913 if (!xchg(&dest->orphan_item_inserted, 1)) {
1914 ret = btrfs_insert_orphan_item(trans,
1915 root->fs_info->tree_root,
1916 dest->root_key.objectid);
1917 BUG_ON(ret);
1918 }
1919
1920 ret = btrfs_end_transaction(trans, root);
1921 BUG_ON(ret);
1922 inode->i_flags |= S_DEAD;
1923 out_up_write:
1924 up_write(&root->fs_info->subvol_sem);
1925 out_unlock:
1926 mutex_unlock(&inode->i_mutex);
1927 if (!err) {
1928 shrink_dcache_sb(root->fs_info->sb);
1929 btrfs_invalidate_inodes(dest);
1930 d_delete(dentry);
1931 }
1932 out_dput:
1933 dput(dentry);
1934 out_unlock_dir:
1935 mutex_unlock(&dir->i_mutex);
1936 mnt_drop_write(file->f_path.mnt);
1937 out:
1938 kfree(vol_args);
1939 return err;
1940 }
1941
1942 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
1943 {
1944 struct inode *inode = fdentry(file)->d_inode;
1945 struct btrfs_root *root = BTRFS_I(inode)->root;
1946 struct btrfs_ioctl_defrag_range_args *range;
1947 int ret;
1948
1949 if (btrfs_root_readonly(root))
1950 return -EROFS;
1951
1952 ret = mnt_want_write(file->f_path.mnt);
1953 if (ret)
1954 return ret;
1955
1956 switch (inode->i_mode & S_IFMT) {
1957 case S_IFDIR:
1958 if (!capable(CAP_SYS_ADMIN)) {
1959 ret = -EPERM;
1960 goto out;
1961 }
1962 ret = btrfs_defrag_root(root, 0);
1963 if (ret)
1964 goto out;
1965 ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
1966 break;
1967 case S_IFREG:
1968 if (!(file->f_mode & FMODE_WRITE)) {
1969 ret = -EINVAL;
1970 goto out;
1971 }
1972
1973 range = kzalloc(sizeof(*range), GFP_KERNEL);
1974 if (!range) {
1975 ret = -ENOMEM;
1976 goto out;
1977 }
1978
1979 if (argp) {
1980 if (copy_from_user(range, argp,
1981 sizeof(*range))) {
1982 ret = -EFAULT;
1983 kfree(range);
1984 goto out;
1985 }
1986 /* compression requires us to start the IO */
1987 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1988 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
1989 range->extent_thresh = (u32)-1;
1990 }
1991 } else {
1992 /* the rest are all set to zero by kzalloc */
1993 range->len = (u64)-1;
1994 }
1995 ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
1996 range, 0, 0);
1997 if (ret > 0)
1998 ret = 0;
1999 kfree(range);
2000 break;
2001 default:
2002 ret = -EINVAL;
2003 }
2004 out:
2005 mnt_drop_write(file->f_path.mnt);
2006 return ret;
2007 }
2008
2009 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2010 {
2011 struct btrfs_ioctl_vol_args *vol_args;
2012 int ret;
2013
2014 if (!capable(CAP_SYS_ADMIN))
2015 return -EPERM;
2016
2017 vol_args = memdup_user(arg, sizeof(*vol_args));
2018 if (IS_ERR(vol_args))
2019 return PTR_ERR(vol_args);
2020
2021 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2022 ret = btrfs_init_new_device(root, vol_args->name);
2023
2024 kfree(vol_args);
2025 return ret;
2026 }
2027
2028 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
2029 {
2030 struct btrfs_ioctl_vol_args *vol_args;
2031 int ret;
2032
2033 if (!capable(CAP_SYS_ADMIN))
2034 return -EPERM;
2035
2036 if (root->fs_info->sb->s_flags & MS_RDONLY)
2037 return -EROFS;
2038
2039 vol_args = memdup_user(arg, sizeof(*vol_args));
2040 if (IS_ERR(vol_args))
2041 return PTR_ERR(vol_args);
2042
2043 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2044 ret = btrfs_rm_device(root, vol_args->name);
2045
2046 kfree(vol_args);
2047 return ret;
2048 }
2049
2050 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2051 {
2052 struct btrfs_ioctl_fs_info_args *fi_args;
2053 struct btrfs_device *device;
2054 struct btrfs_device *next;
2055 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2056 int ret = 0;
2057
2058 if (!capable(CAP_SYS_ADMIN))
2059 return -EPERM;
2060
2061 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2062 if (!fi_args)
2063 return -ENOMEM;
2064
2065 fi_args->num_devices = fs_devices->num_devices;
2066 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2067
2068 mutex_lock(&fs_devices->device_list_mutex);
2069 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2070 if (device->devid > fi_args->max_id)
2071 fi_args->max_id = device->devid;
2072 }
2073 mutex_unlock(&fs_devices->device_list_mutex);
2074
2075 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2076 ret = -EFAULT;
2077
2078 kfree(fi_args);
2079 return ret;
2080 }
2081
2082 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2083 {
2084 struct btrfs_ioctl_dev_info_args *di_args;
2085 struct btrfs_device *dev;
2086 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2087 int ret = 0;
2088 char *s_uuid = NULL;
2089 char empty_uuid[BTRFS_UUID_SIZE] = {0};
2090
2091 if (!capable(CAP_SYS_ADMIN))
2092 return -EPERM;
2093
2094 di_args = memdup_user(arg, sizeof(*di_args));
2095 if (IS_ERR(di_args))
2096 return PTR_ERR(di_args);
2097
2098 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2099 s_uuid = di_args->uuid;
2100
2101 mutex_lock(&fs_devices->device_list_mutex);
2102 dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL);
2103 mutex_unlock(&fs_devices->device_list_mutex);
2104
2105 if (!dev) {
2106 ret = -ENODEV;
2107 goto out;
2108 }
2109
2110 di_args->devid = dev->devid;
2111 di_args->bytes_used = dev->bytes_used;
2112 di_args->total_bytes = dev->total_bytes;
2113 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2114 strncpy(di_args->path, dev->name, sizeof(di_args->path));
2115
2116 out:
2117 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2118 ret = -EFAULT;
2119
2120 kfree(di_args);
2121 return ret;
2122 }
2123
2124 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2125 u64 off, u64 olen, u64 destoff)
2126 {
2127 struct inode *inode = fdentry(file)->d_inode;
2128 struct btrfs_root *root = BTRFS_I(inode)->root;
2129 struct file *src_file;
2130 struct inode *src;
2131 struct btrfs_trans_handle *trans;
2132 struct btrfs_path *path;
2133 struct extent_buffer *leaf;
2134 char *buf;
2135 struct btrfs_key key;
2136 u32 nritems;
2137 int slot;
2138 int ret;
2139 u64 len = olen;
2140 u64 bs = root->fs_info->sb->s_blocksize;
2141 u64 hint_byte;
2142
2143 /*
2144 * TODO:
2145 * - split compressed inline extents. annoying: we need to
2146 * decompress into destination's address_space (the file offset
2147 * may change, so source mapping won't do), then recompress (or
2148 * otherwise reinsert) a subrange.
2149 * - allow ranges within the same file to be cloned (provided
2150 * they don't overlap)?
2151 */
2152
2153 /* the destination must be opened for writing */
2154 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2155 return -EINVAL;
2156
2157 if (btrfs_root_readonly(root))
2158 return -EROFS;
2159
2160 ret = mnt_want_write(file->f_path.mnt);
2161 if (ret)
2162 return ret;
2163
2164 src_file = fget(srcfd);
2165 if (!src_file) {
2166 ret = -EBADF;
2167 goto out_drop_write;
2168 }
2169
2170 src = src_file->f_dentry->d_inode;
2171
2172 ret = -EINVAL;
2173 if (src == inode)
2174 goto out_fput;
2175
2176 /* the src must be open for reading */
2177 if (!(src_file->f_mode & FMODE_READ))
2178 goto out_fput;
2179
2180 /* don't make the dst file partly checksummed */
2181 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2182 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2183 goto out_fput;
2184
2185 ret = -EISDIR;
2186 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2187 goto out_fput;
2188
2189 ret = -EXDEV;
2190 if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
2191 goto out_fput;
2192
2193 ret = -ENOMEM;
2194 buf = vmalloc(btrfs_level_size(root, 0));
2195 if (!buf)
2196 goto out_fput;
2197
2198 path = btrfs_alloc_path();
2199 if (!path) {
2200 vfree(buf);
2201 goto out_fput;
2202 }
2203 path->reada = 2;
2204
2205 if (inode < src) {
2206 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2207 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2208 } else {
2209 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2210 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2211 }
2212
2213 /* determine range to clone */
2214 ret = -EINVAL;
2215 if (off + len > src->i_size || off + len < off)
2216 goto out_unlock;
2217 if (len == 0)
2218 olen = len = src->i_size - off;
2219 /* if we extend to eof, continue to block boundary */
2220 if (off + len == src->i_size)
2221 len = ALIGN(src->i_size, bs) - off;
2222
2223 /* verify the end result is block aligned */
2224 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2225 !IS_ALIGNED(destoff, bs))
2226 goto out_unlock;
2227
2228 if (destoff > inode->i_size) {
2229 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2230 if (ret)
2231 goto out_unlock;
2232 }
2233
2234 /* truncate page cache pages from target inode range */
2235 truncate_inode_pages_range(&inode->i_data, destoff,
2236 PAGE_CACHE_ALIGN(destoff + len) - 1);
2237
2238 /* do any pending delalloc/csum calc on src, one way or
2239 another, and lock file content */
2240 while (1) {
2241 struct btrfs_ordered_extent *ordered;
2242 lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2243 ordered = btrfs_lookup_first_ordered_extent(src, off+len);
2244 if (!ordered &&
2245 !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len,
2246 EXTENT_DELALLOC, 0, NULL))
2247 break;
2248 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2249 if (ordered)
2250 btrfs_put_ordered_extent(ordered);
2251 btrfs_wait_ordered_range(src, off, len);
2252 }
2253
2254 /* clone data */
2255 key.objectid = btrfs_ino(src);
2256 key.type = BTRFS_EXTENT_DATA_KEY;
2257 key.offset = 0;
2258
2259 while (1) {
2260 /*
2261 * note the key will change type as we walk through the
2262 * tree.
2263 */
2264 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2265 if (ret < 0)
2266 goto out;
2267
2268 nritems = btrfs_header_nritems(path->nodes[0]);
2269 if (path->slots[0] >= nritems) {
2270 ret = btrfs_next_leaf(root, path);
2271 if (ret < 0)
2272 goto out;
2273 if (ret > 0)
2274 break;
2275 nritems = btrfs_header_nritems(path->nodes[0]);
2276 }
2277 leaf = path->nodes[0];
2278 slot = path->slots[0];
2279
2280 btrfs_item_key_to_cpu(leaf, &key, slot);
2281 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2282 key.objectid != btrfs_ino(src))
2283 break;
2284
2285 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2286 struct btrfs_file_extent_item *extent;
2287 int type;
2288 u32 size;
2289 struct btrfs_key new_key;
2290 u64 disko = 0, diskl = 0;
2291 u64 datao = 0, datal = 0;
2292 u8 comp;
2293 u64 endoff;
2294
2295 size = btrfs_item_size_nr(leaf, slot);
2296 read_extent_buffer(leaf, buf,
2297 btrfs_item_ptr_offset(leaf, slot),
2298 size);
2299
2300 extent = btrfs_item_ptr(leaf, slot,
2301 struct btrfs_file_extent_item);
2302 comp = btrfs_file_extent_compression(leaf, extent);
2303 type = btrfs_file_extent_type(leaf, extent);
2304 if (type == BTRFS_FILE_EXTENT_REG ||
2305 type == BTRFS_FILE_EXTENT_PREALLOC) {
2306 disko = btrfs_file_extent_disk_bytenr(leaf,
2307 extent);
2308 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2309 extent);
2310 datao = btrfs_file_extent_offset(leaf, extent);
2311 datal = btrfs_file_extent_num_bytes(leaf,
2312 extent);
2313 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2314 /* take upper bound, may be compressed */
2315 datal = btrfs_file_extent_ram_bytes(leaf,
2316 extent);
2317 }
2318 btrfs_release_path(path);
2319
2320 if (key.offset + datal <= off ||
2321 key.offset >= off+len)
2322 goto next;
2323
2324 memcpy(&new_key, &key, sizeof(new_key));
2325 new_key.objectid = btrfs_ino(inode);
2326 if (off <= key.offset)
2327 new_key.offset = key.offset + destoff - off;
2328 else
2329 new_key.offset = destoff;
2330
2331 /*
2332 * 1 - adjusting old extent (we may have to split it)
2333 * 1 - add new extent
2334 * 1 - inode update
2335 */
2336 trans = btrfs_start_transaction(root, 3);
2337 if (IS_ERR(trans)) {
2338 ret = PTR_ERR(trans);
2339 goto out;
2340 }
2341
2342 if (type == BTRFS_FILE_EXTENT_REG ||
2343 type == BTRFS_FILE_EXTENT_PREALLOC) {
2344 /*
2345 * a | --- range to clone ---| b
2346 * | ------------- extent ------------- |
2347 */
2348
2349 /* substract range b */
2350 if (key.offset + datal > off + len)
2351 datal = off + len - key.offset;
2352
2353 /* substract range a */
2354 if (off > key.offset) {
2355 datao += off - key.offset;
2356 datal -= off - key.offset;
2357 }
2358
2359 ret = btrfs_drop_extents(trans, inode,
2360 new_key.offset,
2361 new_key.offset + datal,
2362 &hint_byte, 1);
2363 BUG_ON(ret);
2364
2365 ret = btrfs_insert_empty_item(trans, root, path,
2366 &new_key, size);
2367 BUG_ON(ret);
2368
2369 leaf = path->nodes[0];
2370 slot = path->slots[0];
2371 write_extent_buffer(leaf, buf,
2372 btrfs_item_ptr_offset(leaf, slot),
2373 size);
2374
2375 extent = btrfs_item_ptr(leaf, slot,
2376 struct btrfs_file_extent_item);
2377
2378 /* disko == 0 means it's a hole */
2379 if (!disko)
2380 datao = 0;
2381
2382 btrfs_set_file_extent_offset(leaf, extent,
2383 datao);
2384 btrfs_set_file_extent_num_bytes(leaf, extent,
2385 datal);
2386 if (disko) {
2387 inode_add_bytes(inode, datal);
2388 ret = btrfs_inc_extent_ref(trans, root,
2389 disko, diskl, 0,
2390 root->root_key.objectid,
2391 btrfs_ino(inode),
2392 new_key.offset - datao);
2393 BUG_ON(ret);
2394 }
2395 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2396 u64 skip = 0;
2397 u64 trim = 0;
2398 if (off > key.offset) {
2399 skip = off - key.offset;
2400 new_key.offset += skip;
2401 }
2402
2403 if (key.offset + datal > off+len)
2404 trim = key.offset + datal - (off+len);
2405
2406 if (comp && (skip || trim)) {
2407 ret = -EINVAL;
2408 btrfs_end_transaction(trans, root);
2409 goto out;
2410 }
2411 size -= skip + trim;
2412 datal -= skip + trim;
2413
2414 ret = btrfs_drop_extents(trans, inode,
2415 new_key.offset,
2416 new_key.offset + datal,
2417 &hint_byte, 1);
2418 BUG_ON(ret);
2419
2420 ret = btrfs_insert_empty_item(trans, root, path,
2421 &new_key, size);
2422 BUG_ON(ret);
2423
2424 if (skip) {
2425 u32 start =
2426 btrfs_file_extent_calc_inline_size(0);
2427 memmove(buf+start, buf+start+skip,
2428 datal);
2429 }
2430
2431 leaf = path->nodes[0];
2432 slot = path->slots[0];
2433 write_extent_buffer(leaf, buf,
2434 btrfs_item_ptr_offset(leaf, slot),
2435 size);
2436 inode_add_bytes(inode, datal);
2437 }
2438
2439 btrfs_mark_buffer_dirty(leaf);
2440 btrfs_release_path(path);
2441
2442 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2443
2444 /*
2445 * we round up to the block size at eof when
2446 * determining which extents to clone above,
2447 * but shouldn't round up the file size
2448 */
2449 endoff = new_key.offset + datal;
2450 if (endoff > destoff+olen)
2451 endoff = destoff+olen;
2452 if (endoff > inode->i_size)
2453 btrfs_i_size_write(inode, endoff);
2454
2455 ret = btrfs_update_inode(trans, root, inode);
2456 BUG_ON(ret);
2457 btrfs_end_transaction(trans, root);
2458 }
2459 next:
2460 btrfs_release_path(path);
2461 key.offset++;
2462 }
2463 ret = 0;
2464 out:
2465 btrfs_release_path(path);
2466 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2467 out_unlock:
2468 mutex_unlock(&src->i_mutex);
2469 mutex_unlock(&inode->i_mutex);
2470 vfree(buf);
2471 btrfs_free_path(path);
2472 out_fput:
2473 fput(src_file);
2474 out_drop_write:
2475 mnt_drop_write(file->f_path.mnt);
2476 return ret;
2477 }
2478
2479 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2480 {
2481 struct btrfs_ioctl_clone_range_args args;
2482
2483 if (copy_from_user(&args, argp, sizeof(args)))
2484 return -EFAULT;
2485 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2486 args.src_length, args.dest_offset);
2487 }
2488
2489 /*
2490 * there are many ways the trans_start and trans_end ioctls can lead
2491 * to deadlocks. They should only be used by applications that
2492 * basically own the machine, and have a very in depth understanding
2493 * of all the possible deadlocks and enospc problems.
2494 */
2495 static long btrfs_ioctl_trans_start(struct file *file)
2496 {
2497 struct inode *inode = fdentry(file)->d_inode;
2498 struct btrfs_root *root = BTRFS_I(inode)->root;
2499 struct btrfs_trans_handle *trans;
2500 int ret;
2501
2502 ret = -EPERM;
2503 if (!capable(CAP_SYS_ADMIN))
2504 goto out;
2505
2506 ret = -EINPROGRESS;
2507 if (file->private_data)
2508 goto out;
2509
2510 ret = -EROFS;
2511 if (btrfs_root_readonly(root))
2512 goto out;
2513
2514 ret = mnt_want_write(file->f_path.mnt);
2515 if (ret)
2516 goto out;
2517
2518 atomic_inc(&root->fs_info->open_ioctl_trans);
2519
2520 ret = -ENOMEM;
2521 trans = btrfs_start_ioctl_transaction(root);
2522 if (IS_ERR(trans))
2523 goto out_drop;
2524
2525 file->private_data = trans;
2526 return 0;
2527
2528 out_drop:
2529 atomic_dec(&root->fs_info->open_ioctl_trans);
2530 mnt_drop_write(file->f_path.mnt);
2531 out:
2532 return ret;
2533 }
2534
2535 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2536 {
2537 struct inode *inode = fdentry(file)->d_inode;
2538 struct btrfs_root *root = BTRFS_I(inode)->root;
2539 struct btrfs_root *new_root;
2540 struct btrfs_dir_item *di;
2541 struct btrfs_trans_handle *trans;
2542 struct btrfs_path *path;
2543 struct btrfs_key location;
2544 struct btrfs_disk_key disk_key;
2545 struct btrfs_super_block *disk_super;
2546 u64 features;
2547 u64 objectid = 0;
2548 u64 dir_id;
2549
2550 if (!capable(CAP_SYS_ADMIN))
2551 return -EPERM;
2552
2553 if (copy_from_user(&objectid, argp, sizeof(objectid)))
2554 return -EFAULT;
2555
2556 if (!objectid)
2557 objectid = root->root_key.objectid;
2558
2559 location.objectid = objectid;
2560 location.type = BTRFS_ROOT_ITEM_KEY;
2561 location.offset = (u64)-1;
2562
2563 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2564 if (IS_ERR(new_root))
2565 return PTR_ERR(new_root);
2566
2567 if (btrfs_root_refs(&new_root->root_item) == 0)
2568 return -ENOENT;
2569
2570 path = btrfs_alloc_path();
2571 if (!path)
2572 return -ENOMEM;
2573 path->leave_spinning = 1;
2574
2575 trans = btrfs_start_transaction(root, 1);
2576 if (IS_ERR(trans)) {
2577 btrfs_free_path(path);
2578 return PTR_ERR(trans);
2579 }
2580
2581 dir_id = btrfs_super_root_dir(&root->fs_info->super_copy);
2582 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2583 dir_id, "default", 7, 1);
2584 if (IS_ERR_OR_NULL(di)) {
2585 btrfs_free_path(path);
2586 btrfs_end_transaction(trans, root);
2587 printk(KERN_ERR "Umm, you don't have the default dir item, "
2588 "this isn't going to work\n");
2589 return -ENOENT;
2590 }
2591
2592 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2593 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2594 btrfs_mark_buffer_dirty(path->nodes[0]);
2595 btrfs_free_path(path);
2596
2597 disk_super = &root->fs_info->super_copy;
2598 features = btrfs_super_incompat_flags(disk_super);
2599 if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) {
2600 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL;
2601 btrfs_set_super_incompat_flags(disk_super, features);
2602 }
2603 btrfs_end_transaction(trans, root);
2604
2605 return 0;
2606 }
2607
2608 static void get_block_group_info(struct list_head *groups_list,
2609 struct btrfs_ioctl_space_info *space)
2610 {
2611 struct btrfs_block_group_cache *block_group;
2612
2613 space->total_bytes = 0;
2614 space->used_bytes = 0;
2615 space->flags = 0;
2616 list_for_each_entry(block_group, groups_list, list) {
2617 space->flags = block_group->flags;
2618 space->total_bytes += block_group->key.offset;
2619 space->used_bytes +=
2620 btrfs_block_group_used(&block_group->item);
2621 }
2622 }
2623
2624 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
2625 {
2626 struct btrfs_ioctl_space_args space_args;
2627 struct btrfs_ioctl_space_info space;
2628 struct btrfs_ioctl_space_info *dest;
2629 struct btrfs_ioctl_space_info *dest_orig;
2630 struct btrfs_ioctl_space_info __user *user_dest;
2631 struct btrfs_space_info *info;
2632 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2633 BTRFS_BLOCK_GROUP_SYSTEM,
2634 BTRFS_BLOCK_GROUP_METADATA,
2635 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
2636 int num_types = 4;
2637 int alloc_size;
2638 int ret = 0;
2639 u64 slot_count = 0;
2640 int i, c;
2641
2642 if (copy_from_user(&space_args,
2643 (struct btrfs_ioctl_space_args __user *)arg,
2644 sizeof(space_args)))
2645 return -EFAULT;
2646
2647 for (i = 0; i < num_types; i++) {
2648 struct btrfs_space_info *tmp;
2649
2650 info = NULL;
2651 rcu_read_lock();
2652 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2653 list) {
2654 if (tmp->flags == types[i]) {
2655 info = tmp;
2656 break;
2657 }
2658 }
2659 rcu_read_unlock();
2660
2661 if (!info)
2662 continue;
2663
2664 down_read(&info->groups_sem);
2665 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2666 if (!list_empty(&info->block_groups[c]))
2667 slot_count++;
2668 }
2669 up_read(&info->groups_sem);
2670 }
2671
2672 /* space_slots == 0 means they are asking for a count */
2673 if (space_args.space_slots == 0) {
2674 space_args.total_spaces = slot_count;
2675 goto out;
2676 }
2677
2678 slot_count = min_t(u64, space_args.space_slots, slot_count);
2679
2680 alloc_size = sizeof(*dest) * slot_count;
2681
2682 /* we generally have at most 6 or so space infos, one for each raid
2683 * level. So, a whole page should be more than enough for everyone
2684 */
2685 if (alloc_size > PAGE_CACHE_SIZE)
2686 return -ENOMEM;
2687
2688 space_args.total_spaces = 0;
2689 dest = kmalloc(alloc_size, GFP_NOFS);
2690 if (!dest)
2691 return -ENOMEM;
2692 dest_orig = dest;
2693
2694 /* now we have a buffer to copy into */
2695 for (i = 0; i < num_types; i++) {
2696 struct btrfs_space_info *tmp;
2697
2698 if (!slot_count)
2699 break;
2700
2701 info = NULL;
2702 rcu_read_lock();
2703 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2704 list) {
2705 if (tmp->flags == types[i]) {
2706 info = tmp;
2707 break;
2708 }
2709 }
2710 rcu_read_unlock();
2711
2712 if (!info)
2713 continue;
2714 down_read(&info->groups_sem);
2715 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2716 if (!list_empty(&info->block_groups[c])) {
2717 get_block_group_info(&info->block_groups[c],
2718 &space);
2719 memcpy(dest, &space, sizeof(space));
2720 dest++;
2721 space_args.total_spaces++;
2722 slot_count--;
2723 }
2724 if (!slot_count)
2725 break;
2726 }
2727 up_read(&info->groups_sem);
2728 }
2729
2730 user_dest = (struct btrfs_ioctl_space_info *)
2731 (arg + sizeof(struct btrfs_ioctl_space_args));
2732
2733 if (copy_to_user(user_dest, dest_orig, alloc_size))
2734 ret = -EFAULT;
2735
2736 kfree(dest_orig);
2737 out:
2738 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
2739 ret = -EFAULT;
2740
2741 return ret;
2742 }
2743
2744 /*
2745 * there are many ways the trans_start and trans_end ioctls can lead
2746 * to deadlocks. They should only be used by applications that
2747 * basically own the machine, and have a very in depth understanding
2748 * of all the possible deadlocks and enospc problems.
2749 */
2750 long btrfs_ioctl_trans_end(struct file *file)
2751 {
2752 struct inode *inode = fdentry(file)->d_inode;
2753 struct btrfs_root *root = BTRFS_I(inode)->root;
2754 struct btrfs_trans_handle *trans;
2755
2756 trans = file->private_data;
2757 if (!trans)
2758 return -EINVAL;
2759 file->private_data = NULL;
2760
2761 btrfs_end_transaction(trans, root);
2762
2763 atomic_dec(&root->fs_info->open_ioctl_trans);
2764
2765 mnt_drop_write(file->f_path.mnt);
2766 return 0;
2767 }
2768
2769 static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
2770 {
2771 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2772 struct btrfs_trans_handle *trans;
2773 u64 transid;
2774 int ret;
2775
2776 trans = btrfs_start_transaction(root, 0);
2777 if (IS_ERR(trans))
2778 return PTR_ERR(trans);
2779 transid = trans->transid;
2780 ret = btrfs_commit_transaction_async(trans, root, 0);
2781 if (ret) {
2782 btrfs_end_transaction(trans, root);
2783 return ret;
2784 }
2785
2786 if (argp)
2787 if (copy_to_user(argp, &transid, sizeof(transid)))
2788 return -EFAULT;
2789 return 0;
2790 }
2791
2792 static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
2793 {
2794 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2795 u64 transid;
2796
2797 if (argp) {
2798 if (copy_from_user(&transid, argp, sizeof(transid)))
2799 return -EFAULT;
2800 } else {
2801 transid = 0; /* current trans */
2802 }
2803 return btrfs_wait_for_commit(root, transid);
2804 }
2805
2806 static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg)
2807 {
2808 int ret;
2809 struct btrfs_ioctl_scrub_args *sa;
2810
2811 if (!capable(CAP_SYS_ADMIN))
2812 return -EPERM;
2813
2814 sa = memdup_user(arg, sizeof(*sa));
2815 if (IS_ERR(sa))
2816 return PTR_ERR(sa);
2817
2818 ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end,
2819 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY);
2820
2821 if (copy_to_user(arg, sa, sizeof(*sa)))
2822 ret = -EFAULT;
2823
2824 kfree(sa);
2825 return ret;
2826 }
2827
2828 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
2829 {
2830 if (!capable(CAP_SYS_ADMIN))
2831 return -EPERM;
2832
2833 return btrfs_scrub_cancel(root);
2834 }
2835
2836 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
2837 void __user *arg)
2838 {
2839 struct btrfs_ioctl_scrub_args *sa;
2840 int ret;
2841
2842 if (!capable(CAP_SYS_ADMIN))
2843 return -EPERM;
2844
2845 sa = memdup_user(arg, sizeof(*sa));
2846 if (IS_ERR(sa))
2847 return PTR_ERR(sa);
2848
2849 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
2850
2851 if (copy_to_user(arg, sa, sizeof(*sa)))
2852 ret = -EFAULT;
2853
2854 kfree(sa);
2855 return ret;
2856 }
2857
2858 long btrfs_ioctl(struct file *file, unsigned int
2859 cmd, unsigned long arg)
2860 {
2861 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2862 void __user *argp = (void __user *)arg;
2863
2864 switch (cmd) {
2865 case FS_IOC_GETFLAGS:
2866 return btrfs_ioctl_getflags(file, argp);
2867 case FS_IOC_SETFLAGS:
2868 return btrfs_ioctl_setflags(file, argp);
2869 case FS_IOC_GETVERSION:
2870 return btrfs_ioctl_getversion(file, argp);
2871 case FITRIM:
2872 return btrfs_ioctl_fitrim(file, argp);
2873 case BTRFS_IOC_SNAP_CREATE:
2874 return btrfs_ioctl_snap_create(file, argp, 0);
2875 case BTRFS_IOC_SNAP_CREATE_V2:
2876 return btrfs_ioctl_snap_create_v2(file, argp, 0);
2877 case BTRFS_IOC_SUBVOL_CREATE:
2878 return btrfs_ioctl_snap_create(file, argp, 1);
2879 case BTRFS_IOC_SNAP_DESTROY:
2880 return btrfs_ioctl_snap_destroy(file, argp);
2881 case BTRFS_IOC_SUBVOL_GETFLAGS:
2882 return btrfs_ioctl_subvol_getflags(file, argp);
2883 case BTRFS_IOC_SUBVOL_SETFLAGS:
2884 return btrfs_ioctl_subvol_setflags(file, argp);
2885 case BTRFS_IOC_DEFAULT_SUBVOL:
2886 return btrfs_ioctl_default_subvol(file, argp);
2887 case BTRFS_IOC_DEFRAG:
2888 return btrfs_ioctl_defrag(file, NULL);
2889 case BTRFS_IOC_DEFRAG_RANGE:
2890 return btrfs_ioctl_defrag(file, argp);
2891 case BTRFS_IOC_RESIZE:
2892 return btrfs_ioctl_resize(root, argp);
2893 case BTRFS_IOC_ADD_DEV:
2894 return btrfs_ioctl_add_dev(root, argp);
2895 case BTRFS_IOC_RM_DEV:
2896 return btrfs_ioctl_rm_dev(root, argp);
2897 case BTRFS_IOC_FS_INFO:
2898 return btrfs_ioctl_fs_info(root, argp);
2899 case BTRFS_IOC_DEV_INFO:
2900 return btrfs_ioctl_dev_info(root, argp);
2901 case BTRFS_IOC_BALANCE:
2902 return btrfs_balance(root->fs_info->dev_root);
2903 case BTRFS_IOC_CLONE:
2904 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
2905 case BTRFS_IOC_CLONE_RANGE:
2906 return btrfs_ioctl_clone_range(file, argp);
2907 case BTRFS_IOC_TRANS_START:
2908 return btrfs_ioctl_trans_start(file);
2909 case BTRFS_IOC_TRANS_END:
2910 return btrfs_ioctl_trans_end(file);
2911 case BTRFS_IOC_TREE_SEARCH:
2912 return btrfs_ioctl_tree_search(file, argp);
2913 case BTRFS_IOC_INO_LOOKUP:
2914 return btrfs_ioctl_ino_lookup(file, argp);
2915 case BTRFS_IOC_SPACE_INFO:
2916 return btrfs_ioctl_space_info(root, argp);
2917 case BTRFS_IOC_SYNC:
2918 btrfs_sync_fs(file->f_dentry->d_sb, 1);
2919 return 0;
2920 case BTRFS_IOC_START_SYNC:
2921 return btrfs_ioctl_start_sync(file, argp);
2922 case BTRFS_IOC_WAIT_SYNC:
2923 return btrfs_ioctl_wait_sync(file, argp);
2924 case BTRFS_IOC_SCRUB:
2925 return btrfs_ioctl_scrub(root, argp);
2926 case BTRFS_IOC_SCRUB_CANCEL:
2927 return btrfs_ioctl_scrub_cancel(root, argp);
2928 case BTRFS_IOC_SCRUB_PROGRESS:
2929 return btrfs_ioctl_scrub_progress(root, argp);
2930 }
2931
2932 return -ENOTTY;
2933 }
kernel-based virtual machine