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Btrfs: fix wrong size for the reservation of the, snapshot creation
[linux-2.6.git] / fs / btrfs / ioctl.c
blobc56daa368768a2a1ac90efc48c6839d714c6ddac
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 "compat.h"
46 #include "ctree.h"
47 #include "disk-io.h"
48 #include "transaction.h"
49 #include "btrfs_inode.h"
50 #include "ioctl.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
59 /* Mask out flags that are inappropriate for the given type of inode. */
60 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
61 {
62 if (S_ISDIR(mode))
63 return flags;
64 else if (S_ISREG(mode))
65 return flags & ~FS_DIRSYNC_FL;
66 else
67 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
68 }
69
70 /*
71 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
72 */
73 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
74 {
75 unsigned int iflags = 0;
76
77 if (flags & BTRFS_INODE_SYNC)
78 iflags |= FS_SYNC_FL;
79 if (flags & BTRFS_INODE_IMMUTABLE)
80 iflags |= FS_IMMUTABLE_FL;
81 if (flags & BTRFS_INODE_APPEND)
82 iflags |= FS_APPEND_FL;
83 if (flags & BTRFS_INODE_NODUMP)
84 iflags |= FS_NODUMP_FL;
85 if (flags & BTRFS_INODE_NOATIME)
86 iflags |= FS_NOATIME_FL;
87 if (flags & BTRFS_INODE_DIRSYNC)
88 iflags |= FS_DIRSYNC_FL;
89 if (flags & BTRFS_INODE_NODATACOW)
90 iflags |= FS_NOCOW_FL;
91
92 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
93 iflags |= FS_COMPR_FL;
94 else if (flags & BTRFS_INODE_NOCOMPRESS)
95 iflags |= FS_NOCOMP_FL;
96
97 return iflags;
98 }
99
100 /*
101 * Update inode->i_flags based on the btrfs internal flags.
102 */
103 void btrfs_update_iflags(struct inode *inode)
104 {
105 struct btrfs_inode *ip = BTRFS_I(inode);
106
107 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
108
109 if (ip->flags & BTRFS_INODE_SYNC)
110 inode->i_flags |= S_SYNC;
111 if (ip->flags & BTRFS_INODE_IMMUTABLE)
112 inode->i_flags |= S_IMMUTABLE;
113 if (ip->flags & BTRFS_INODE_APPEND)
114 inode->i_flags |= S_APPEND;
115 if (ip->flags & BTRFS_INODE_NOATIME)
116 inode->i_flags |= S_NOATIME;
117 if (ip->flags & BTRFS_INODE_DIRSYNC)
118 inode->i_flags |= S_DIRSYNC;
119 }
120
121 /*
122 * Inherit flags from the parent inode.
123 *
124 * Currently only the compression flags and the cow flags are inherited.
125 */
126 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
127 {
128 unsigned int flags;
129
130 if (!dir)
131 return;
132
133 flags = BTRFS_I(dir)->flags;
134
135 if (flags & BTRFS_INODE_NOCOMPRESS) {
136 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
137 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
138 } else if (flags & BTRFS_INODE_COMPRESS) {
139 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
140 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
141 }
142
143 if (flags & BTRFS_INODE_NODATACOW)
144 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
145
146 btrfs_update_iflags(inode);
147 }
148
149 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
150 {
151 struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
152 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
153
154 if (copy_to_user(arg, &flags, sizeof(flags)))
155 return -EFAULT;
156 return 0;
157 }
158
159 static int check_flags(unsigned int flags)
160 {
161 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
162 FS_NOATIME_FL | FS_NODUMP_FL | \
163 FS_SYNC_FL | FS_DIRSYNC_FL | \
164 FS_NOCOMP_FL | FS_COMPR_FL |
165 FS_NOCOW_FL))
166 return -EOPNOTSUPP;
167
168 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
169 return -EINVAL;
170
171 return 0;
172 }
173
174 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
175 {
176 struct inode *inode = file->f_path.dentry->d_inode;
177 struct btrfs_inode *ip = BTRFS_I(inode);
178 struct btrfs_root *root = ip->root;
179 struct btrfs_trans_handle *trans;
180 unsigned int flags, oldflags;
181 int ret;
182 u64 ip_oldflags;
183 unsigned int i_oldflags;
184
185 if (btrfs_root_readonly(root))
186 return -EROFS;
187
188 if (copy_from_user(&flags, arg, sizeof(flags)))
189 return -EFAULT;
190
191 ret = check_flags(flags);
192 if (ret)
193 return ret;
194
195 if (!inode_owner_or_capable(inode))
196 return -EACCES;
197
198 ret = mnt_want_write_file(file);
199 if (ret)
200 return ret;
201
202 mutex_lock(&inode->i_mutex);
203
204 ip_oldflags = ip->flags;
205 i_oldflags = inode->i_flags;
206
207 flags = btrfs_mask_flags(inode->i_mode, flags);
208 oldflags = btrfs_flags_to_ioctl(ip->flags);
209 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
210 if (!capable(CAP_LINUX_IMMUTABLE)) {
211 ret = -EPERM;
212 goto out_unlock;
213 }
214 }
215
216 if (flags & FS_SYNC_FL)
217 ip->flags |= BTRFS_INODE_SYNC;
218 else
219 ip->flags &= ~BTRFS_INODE_SYNC;
220 if (flags & FS_IMMUTABLE_FL)
221 ip->flags |= BTRFS_INODE_IMMUTABLE;
222 else
223 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
224 if (flags & FS_APPEND_FL)
225 ip->flags |= BTRFS_INODE_APPEND;
226 else
227 ip->flags &= ~BTRFS_INODE_APPEND;
228 if (flags & FS_NODUMP_FL)
229 ip->flags |= BTRFS_INODE_NODUMP;
230 else
231 ip->flags &= ~BTRFS_INODE_NODUMP;
232 if (flags & FS_NOATIME_FL)
233 ip->flags |= BTRFS_INODE_NOATIME;
234 else
235 ip->flags &= ~BTRFS_INODE_NOATIME;
236 if (flags & FS_DIRSYNC_FL)
237 ip->flags |= BTRFS_INODE_DIRSYNC;
238 else
239 ip->flags &= ~BTRFS_INODE_DIRSYNC;
240 if (flags & FS_NOCOW_FL)
241 ip->flags |= BTRFS_INODE_NODATACOW;
242 else
243 ip->flags &= ~BTRFS_INODE_NODATACOW;
244
245 /*
246 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
247 * flag may be changed automatically if compression code won't make
248 * things smaller.
249 */
250 if (flags & FS_NOCOMP_FL) {
251 ip->flags &= ~BTRFS_INODE_COMPRESS;
252 ip->flags |= BTRFS_INODE_NOCOMPRESS;
253 } else if (flags & FS_COMPR_FL) {
254 ip->flags |= BTRFS_INODE_COMPRESS;
255 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
256 } else {
257 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
258 }
259
260 trans = btrfs_start_transaction(root, 1);
261 if (IS_ERR(trans)) {
262 ret = PTR_ERR(trans);
263 goto out_drop;
264 }
265
266 btrfs_update_iflags(inode);
267 inode_inc_iversion(inode);
268 inode->i_ctime = CURRENT_TIME;
269 ret = btrfs_update_inode(trans, root, inode);
270
271 btrfs_end_transaction(trans, root);
272 out_drop:
273 if (ret) {
274 ip->flags = ip_oldflags;
275 inode->i_flags = i_oldflags;
276 }
277
278 out_unlock:
279 mutex_unlock(&inode->i_mutex);
280 mnt_drop_write_file(file);
281 return ret;
282 }
283
284 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
285 {
286 struct inode *inode = file->f_path.dentry->d_inode;
287
288 return put_user(inode->i_generation, arg);
289 }
290
291 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
292 {
293 struct btrfs_fs_info *fs_info = btrfs_sb(fdentry(file)->d_sb);
294 struct btrfs_device *device;
295 struct request_queue *q;
296 struct fstrim_range range;
297 u64 minlen = ULLONG_MAX;
298 u64 num_devices = 0;
299 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
300 int ret;
301
302 if (!capable(CAP_SYS_ADMIN))
303 return -EPERM;
304
305 rcu_read_lock();
306 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
307 dev_list) {
308 if (!device->bdev)
309 continue;
310 q = bdev_get_queue(device->bdev);
311 if (blk_queue_discard(q)) {
312 num_devices++;
313 minlen = min((u64)q->limits.discard_granularity,
314 minlen);
315 }
316 }
317 rcu_read_unlock();
318
319 if (!num_devices)
320 return -EOPNOTSUPP;
321 if (copy_from_user(&range, arg, sizeof(range)))
322 return -EFAULT;
323 if (range.start > total_bytes)
324 return -EINVAL;
325
326 range.len = min(range.len, total_bytes - range.start);
327 range.minlen = max(range.minlen, minlen);
328 ret = btrfs_trim_fs(fs_info->tree_root, &range);
329 if (ret < 0)
330 return ret;
331
332 if (copy_to_user(arg, &range, sizeof(range)))
333 return -EFAULT;
334
335 return 0;
336 }
337
338 static noinline int create_subvol(struct btrfs_root *root,
339 struct dentry *dentry,
340 char *name, int namelen,
341 u64 *async_transid,
342 struct btrfs_qgroup_inherit **inherit)
343 {
344 struct btrfs_trans_handle *trans;
345 struct btrfs_key key;
346 struct btrfs_root_item root_item;
347 struct btrfs_inode_item *inode_item;
348 struct extent_buffer *leaf;
349 struct btrfs_root *new_root;
350 struct dentry *parent = dentry->d_parent;
351 struct inode *dir;
352 struct timespec cur_time = CURRENT_TIME;
353 int ret;
354 int err;
355 u64 objectid;
356 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
357 u64 index = 0;
358 uuid_le new_uuid;
359
360 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
361 if (ret)
362 return ret;
363
364 dir = parent->d_inode;
365
366 /*
367 * 1 - inode item
368 * 2 - refs
369 * 1 - root item
370 * 2 - dir items
371 */
372 trans = btrfs_start_transaction(root, 6);
373 if (IS_ERR(trans))
374 return PTR_ERR(trans);
375
376 ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid,
377 inherit ? *inherit : NULL);
378 if (ret)
379 goto fail;
380
381 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
382 0, objectid, NULL, 0, 0, 0);
383 if (IS_ERR(leaf)) {
384 ret = PTR_ERR(leaf);
385 goto fail;
386 }
387
388 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
389 btrfs_set_header_bytenr(leaf, leaf->start);
390 btrfs_set_header_generation(leaf, trans->transid);
391 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
392 btrfs_set_header_owner(leaf, objectid);
393
394 write_extent_buffer(leaf, root->fs_info->fsid,
395 (unsigned long)btrfs_header_fsid(leaf),
396 BTRFS_FSID_SIZE);
397 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
398 (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
399 BTRFS_UUID_SIZE);
400 btrfs_mark_buffer_dirty(leaf);
401
402 memset(&root_item, 0, sizeof(root_item));
403
404 inode_item = &root_item.inode;
405 inode_item->generation = cpu_to_le64(1);
406 inode_item->size = cpu_to_le64(3);
407 inode_item->nlink = cpu_to_le32(1);
408 inode_item->nbytes = cpu_to_le64(root->leafsize);
409 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
410
411 root_item.flags = 0;
412 root_item.byte_limit = 0;
413 inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
414
415 btrfs_set_root_bytenr(&root_item, leaf->start);
416 btrfs_set_root_generation(&root_item, trans->transid);
417 btrfs_set_root_level(&root_item, 0);
418 btrfs_set_root_refs(&root_item, 1);
419 btrfs_set_root_used(&root_item, leaf->len);
420 btrfs_set_root_last_snapshot(&root_item, 0);
421
422 btrfs_set_root_generation_v2(&root_item,
423 btrfs_root_generation(&root_item));
424 uuid_le_gen(&new_uuid);
425 memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
426 root_item.otime.sec = cpu_to_le64(cur_time.tv_sec);
427 root_item.otime.nsec = cpu_to_le32(cur_time.tv_nsec);
428 root_item.ctime = root_item.otime;
429 btrfs_set_root_ctransid(&root_item, trans->transid);
430 btrfs_set_root_otransid(&root_item, trans->transid);
431
432 btrfs_tree_unlock(leaf);
433 free_extent_buffer(leaf);
434 leaf = NULL;
435
436 btrfs_set_root_dirid(&root_item, new_dirid);
437
438 key.objectid = objectid;
439 key.offset = 0;
440 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
441 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
442 &root_item);
443 if (ret)
444 goto fail;
445
446 key.offset = (u64)-1;
447 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
448 if (IS_ERR(new_root)) {
449 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
450 ret = PTR_ERR(new_root);
451 goto fail;
452 }
453
454 btrfs_record_root_in_trans(trans, new_root);
455
456 ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
457 if (ret) {
458 /* We potentially lose an unused inode item here */
459 btrfs_abort_transaction(trans, root, ret);
460 goto fail;
461 }
462
463 /*
464 * insert the directory item
465 */
466 ret = btrfs_set_inode_index(dir, &index);
467 if (ret) {
468 btrfs_abort_transaction(trans, root, ret);
469 goto fail;
470 }
471
472 ret = btrfs_insert_dir_item(trans, root,
473 name, namelen, dir, &key,
474 BTRFS_FT_DIR, index);
475 if (ret) {
476 btrfs_abort_transaction(trans, root, ret);
477 goto fail;
478 }
479
480 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
481 ret = btrfs_update_inode(trans, root, dir);
482 BUG_ON(ret);
483
484 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
485 objectid, root->root_key.objectid,
486 btrfs_ino(dir), index, name, namelen);
487
488 BUG_ON(ret);
489
490 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
491 fail:
492 if (async_transid) {
493 *async_transid = trans->transid;
494 err = btrfs_commit_transaction_async(trans, root, 1);
495 } else {
496 err = btrfs_commit_transaction(trans, root);
497 }
498 if (err && !ret)
499 ret = err;
500 return ret;
501 }
502
503 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
504 char *name, int namelen, u64 *async_transid,
505 bool readonly, struct btrfs_qgroup_inherit **inherit)
506 {
507 struct inode *inode;
508 struct btrfs_pending_snapshot *pending_snapshot;
509 struct btrfs_trans_handle *trans;
510 int ret;
511
512 if (!root->ref_cows)
513 return -EINVAL;
514
515 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
516 if (!pending_snapshot)
517 return -ENOMEM;
518
519 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
520 BTRFS_BLOCK_RSV_TEMP);
521 pending_snapshot->dentry = dentry;
522 pending_snapshot->root = root;
523 pending_snapshot->readonly = readonly;
524 if (inherit) {
525 pending_snapshot->inherit = *inherit;
526 *inherit = NULL; /* take responsibility to free it */
527 }
528
529 trans = btrfs_start_transaction(root->fs_info->extent_root, 6);
530 if (IS_ERR(trans)) {
531 ret = PTR_ERR(trans);
532 goto fail;
533 }
534
535 ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
536 BUG_ON(ret);
537
538 spin_lock(&root->fs_info->trans_lock);
539 list_add(&pending_snapshot->list,
540 &trans->transaction->pending_snapshots);
541 spin_unlock(&root->fs_info->trans_lock);
542 if (async_transid) {
543 *async_transid = trans->transid;
544 ret = btrfs_commit_transaction_async(trans,
545 root->fs_info->extent_root, 1);
546 } else {
547 ret = btrfs_commit_transaction(trans,
548 root->fs_info->extent_root);
549 }
550 BUG_ON(ret);
551
552 ret = pending_snapshot->error;
553 if (ret)
554 goto fail;
555
556 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
557 if (ret)
558 goto fail;
559
560 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
561 if (IS_ERR(inode)) {
562 ret = PTR_ERR(inode);
563 goto fail;
564 }
565 BUG_ON(!inode);
566 d_instantiate(dentry, inode);
567 ret = 0;
568 fail:
569 kfree(pending_snapshot);
570 return ret;
571 }
572
573 /* copy of check_sticky in fs/namei.c()
574 * It's inline, so penalty for filesystems that don't use sticky bit is
575 * minimal.
576 */
577 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
578 {
579 uid_t fsuid = current_fsuid();
580
581 if (!(dir->i_mode & S_ISVTX))
582 return 0;
583 if (inode->i_uid == fsuid)
584 return 0;
585 if (dir->i_uid == fsuid)
586 return 0;
587 return !capable(CAP_FOWNER);
588 }
589
590 /* copy of may_delete in fs/namei.c()
591 * Check whether we can remove a link victim from directory dir, check
592 * whether the type of victim is right.
593 * 1. We can't do it if dir is read-only (done in permission())
594 * 2. We should have write and exec permissions on dir
595 * 3. We can't remove anything from append-only dir
596 * 4. We can't do anything with immutable dir (done in permission())
597 * 5. If the sticky bit on dir is set we should either
598 * a. be owner of dir, or
599 * b. be owner of victim, or
600 * c. have CAP_FOWNER capability
601 * 6. If the victim is append-only or immutable we can't do antyhing with
602 * links pointing to it.
603 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
604 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
605 * 9. We can't remove a root or mountpoint.
606 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
607 * nfs_async_unlink().
608 */
609
610 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
611 {
612 int error;
613
614 if (!victim->d_inode)
615 return -ENOENT;
616
617 BUG_ON(victim->d_parent->d_inode != dir);
618 audit_inode_child(victim, dir);
619
620 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
621 if (error)
622 return error;
623 if (IS_APPEND(dir))
624 return -EPERM;
625 if (btrfs_check_sticky(dir, victim->d_inode)||
626 IS_APPEND(victim->d_inode)||
627 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
628 return -EPERM;
629 if (isdir) {
630 if (!S_ISDIR(victim->d_inode->i_mode))
631 return -ENOTDIR;
632 if (IS_ROOT(victim))
633 return -EBUSY;
634 } else if (S_ISDIR(victim->d_inode->i_mode))
635 return -EISDIR;
636 if (IS_DEADDIR(dir))
637 return -ENOENT;
638 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
639 return -EBUSY;
640 return 0;
641 }
642
643 /* copy of may_create in fs/namei.c() */
644 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
645 {
646 if (child->d_inode)
647 return -EEXIST;
648 if (IS_DEADDIR(dir))
649 return -ENOENT;
650 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
651 }
652
653 /*
654 * Create a new subvolume below @parent. This is largely modeled after
655 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
656 * inside this filesystem so it's quite a bit simpler.
657 */
658 static noinline int btrfs_mksubvol(struct path *parent,
659 char *name, int namelen,
660 struct btrfs_root *snap_src,
661 u64 *async_transid, bool readonly,
662 struct btrfs_qgroup_inherit **inherit)
663 {
664 struct inode *dir = parent->dentry->d_inode;
665 struct dentry *dentry;
666 int error;
667
668 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
669
670 dentry = lookup_one_len(name, parent->dentry, namelen);
671 error = PTR_ERR(dentry);
672 if (IS_ERR(dentry))
673 goto out_unlock;
674
675 error = -EEXIST;
676 if (dentry->d_inode)
677 goto out_dput;
678
679 error = btrfs_may_create(dir, dentry);
680 if (error)
681 goto out_dput;
682
683 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
684
685 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
686 goto out_up_read;
687
688 if (snap_src) {
689 error = create_snapshot(snap_src, dentry, name, namelen,
690 async_transid, readonly, inherit);
691 } else {
692 error = create_subvol(BTRFS_I(dir)->root, dentry,
693 name, namelen, async_transid, inherit);
694 }
695 if (!error)
696 fsnotify_mkdir(dir, dentry);
697 out_up_read:
698 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
699 out_dput:
700 dput(dentry);
701 out_unlock:
702 mutex_unlock(&dir->i_mutex);
703 return error;
704 }
705
706 /*
707 * When we're defragging a range, we don't want to kick it off again
708 * if it is really just waiting for delalloc to send it down.
709 * If we find a nice big extent or delalloc range for the bytes in the
710 * file you want to defrag, we return 0 to let you know to skip this
711 * part of the file
712 */
713 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
714 {
715 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
716 struct extent_map *em = NULL;
717 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
718 u64 end;
719
720 read_lock(&em_tree->lock);
721 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
722 read_unlock(&em_tree->lock);
723
724 if (em) {
725 end = extent_map_end(em);
726 free_extent_map(em);
727 if (end - offset > thresh)
728 return 0;
729 }
730 /* if we already have a nice delalloc here, just stop */
731 thresh /= 2;
732 end = count_range_bits(io_tree, &offset, offset + thresh,
733 thresh, EXTENT_DELALLOC, 1);
734 if (end >= thresh)
735 return 0;
736 return 1;
737 }
738
739 /*
740 * helper function to walk through a file and find extents
741 * newer than a specific transid, and smaller than thresh.
742 *
743 * This is used by the defragging code to find new and small
744 * extents
745 */
746 static int find_new_extents(struct btrfs_root *root,
747 struct inode *inode, u64 newer_than,
748 u64 *off, int thresh)
749 {
750 struct btrfs_path *path;
751 struct btrfs_key min_key;
752 struct btrfs_key max_key;
753 struct extent_buffer *leaf;
754 struct btrfs_file_extent_item *extent;
755 int type;
756 int ret;
757 u64 ino = btrfs_ino(inode);
758
759 path = btrfs_alloc_path();
760 if (!path)
761 return -ENOMEM;
762
763 min_key.objectid = ino;
764 min_key.type = BTRFS_EXTENT_DATA_KEY;
765 min_key.offset = *off;
766
767 max_key.objectid = ino;
768 max_key.type = (u8)-1;
769 max_key.offset = (u64)-1;
770
771 path->keep_locks = 1;
772
773 while(1) {
774 ret = btrfs_search_forward(root, &min_key, &max_key,
775 path, 0, newer_than);
776 if (ret != 0)
777 goto none;
778 if (min_key.objectid != ino)
779 goto none;
780 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
781 goto none;
782
783 leaf = path->nodes[0];
784 extent = btrfs_item_ptr(leaf, path->slots[0],
785 struct btrfs_file_extent_item);
786
787 type = btrfs_file_extent_type(leaf, extent);
788 if (type == BTRFS_FILE_EXTENT_REG &&
789 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
790 check_defrag_in_cache(inode, min_key.offset, thresh)) {
791 *off = min_key.offset;
792 btrfs_free_path(path);
793 return 0;
794 }
795
796 if (min_key.offset == (u64)-1)
797 goto none;
798
799 min_key.offset++;
800 btrfs_release_path(path);
801 }
802 none:
803 btrfs_free_path(path);
804 return -ENOENT;
805 }
806
807 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
808 {
809 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
810 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
811 struct extent_map *em;
812 u64 len = PAGE_CACHE_SIZE;
813
814 /*
815 * hopefully we have this extent in the tree already, try without
816 * the full extent lock
817 */
818 read_lock(&em_tree->lock);
819 em = lookup_extent_mapping(em_tree, start, len);
820 read_unlock(&em_tree->lock);
821
822 if (!em) {
823 /* get the big lock and read metadata off disk */
824 lock_extent(io_tree, start, start + len - 1);
825 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
826 unlock_extent(io_tree, start, start + len - 1);
827
828 if (IS_ERR(em))
829 return NULL;
830 }
831
832 return em;
833 }
834
835 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
836 {
837 struct extent_map *next;
838 bool ret = true;
839
840 /* this is the last extent */
841 if (em->start + em->len >= i_size_read(inode))
842 return false;
843
844 next = defrag_lookup_extent(inode, em->start + em->len);
845 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
846 ret = false;
847
848 free_extent_map(next);
849 return ret;
850 }
851
852 static int should_defrag_range(struct inode *inode, u64 start, int thresh,
853 u64 *last_len, u64 *skip, u64 *defrag_end,
854 int compress)
855 {
856 struct extent_map *em;
857 int ret = 1;
858 bool next_mergeable = true;
859
860 /*
861 * make sure that once we start defragging an extent, we keep on
862 * defragging it
863 */
864 if (start < *defrag_end)
865 return 1;
866
867 *skip = 0;
868
869 em = defrag_lookup_extent(inode, start);
870 if (!em)
871 return 0;
872
873 /* this will cover holes, and inline extents */
874 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
875 ret = 0;
876 goto out;
877 }
878
879 next_mergeable = defrag_check_next_extent(inode, em);
880
881 /*
882 * we hit a real extent, if it is big or the next extent is not a
883 * real extent, don't bother defragging it
884 */
885 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
886 (em->len >= thresh || !next_mergeable))
887 ret = 0;
888 out:
889 /*
890 * last_len ends up being a counter of how many bytes we've defragged.
891 * every time we choose not to defrag an extent, we reset *last_len
892 * so that the next tiny extent will force a defrag.
893 *
894 * The end result of this is that tiny extents before a single big
895 * extent will force at least part of that big extent to be defragged.
896 */
897 if (ret) {
898 *defrag_end = extent_map_end(em);
899 } else {
900 *last_len = 0;
901 *skip = extent_map_end(em);
902 *defrag_end = 0;
903 }
904
905 free_extent_map(em);
906 return ret;
907 }
908
909 /*
910 * it doesn't do much good to defrag one or two pages
911 * at a time. This pulls in a nice chunk of pages
912 * to COW and defrag.
913 *
914 * It also makes sure the delalloc code has enough
915 * dirty data to avoid making new small extents as part
916 * of the defrag
917 *
918 * It's a good idea to start RA on this range
919 * before calling this.
920 */
921 static int cluster_pages_for_defrag(struct inode *inode,
922 struct page **pages,
923 unsigned long start_index,
924 int num_pages)
925 {
926 unsigned long file_end;
927 u64 isize = i_size_read(inode);
928 u64 page_start;
929 u64 page_end;
930 u64 page_cnt;
931 int ret;
932 int i;
933 int i_done;
934 struct btrfs_ordered_extent *ordered;
935 struct extent_state *cached_state = NULL;
936 struct extent_io_tree *tree;
937 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
938
939 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
940 if (!isize || start_index > file_end)
941 return 0;
942
943 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
944
945 ret = btrfs_delalloc_reserve_space(inode,
946 page_cnt << PAGE_CACHE_SHIFT);
947 if (ret)
948 return ret;
949 i_done = 0;
950 tree = &BTRFS_I(inode)->io_tree;
951
952 /* step one, lock all the pages */
953 for (i = 0; i < page_cnt; i++) {
954 struct page *page;
955 again:
956 page = find_or_create_page(inode->i_mapping,
957 start_index + i, mask);
958 if (!page)
959 break;
960
961 page_start = page_offset(page);
962 page_end = page_start + PAGE_CACHE_SIZE - 1;
963 while (1) {
964 lock_extent(tree, page_start, page_end);
965 ordered = btrfs_lookup_ordered_extent(inode,
966 page_start);
967 unlock_extent(tree, page_start, page_end);
968 if (!ordered)
969 break;
970
971 unlock_page(page);
972 btrfs_start_ordered_extent(inode, ordered, 1);
973 btrfs_put_ordered_extent(ordered);
974 lock_page(page);
975 /*
976 * we unlocked the page above, so we need check if
977 * it was released or not.
978 */
979 if (page->mapping != inode->i_mapping) {
980 unlock_page(page);
981 page_cache_release(page);
982 goto again;
983 }
984 }
985
986 if (!PageUptodate(page)) {
987 btrfs_readpage(NULL, page);
988 lock_page(page);
989 if (!PageUptodate(page)) {
990 unlock_page(page);
991 page_cache_release(page);
992 ret = -EIO;
993 break;
994 }
995 }
996
997 if (page->mapping != inode->i_mapping) {
998 unlock_page(page);
999 page_cache_release(page);
1000 goto again;
1001 }
1002
1003 pages[i] = page;
1004 i_done++;
1005 }
1006 if (!i_done || ret)
1007 goto out;
1008
1009 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1010 goto out;
1011
1012 /*
1013 * so now we have a nice long stream of locked
1014 * and up to date pages, lets wait on them
1015 */
1016 for (i = 0; i < i_done; i++)
1017 wait_on_page_writeback(pages[i]);
1018
1019 page_start = page_offset(pages[0]);
1020 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1021
1022 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1023 page_start, page_end - 1, 0, &cached_state);
1024 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1025 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1026 EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
1027 GFP_NOFS);
1028
1029 if (i_done != page_cnt) {
1030 spin_lock(&BTRFS_I(inode)->lock);
1031 BTRFS_I(inode)->outstanding_extents++;
1032 spin_unlock(&BTRFS_I(inode)->lock);
1033 btrfs_delalloc_release_space(inode,
1034 (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1035 }
1036
1037
1038 btrfs_set_extent_delalloc(inode, page_start, page_end - 1,
1039 &cached_state);
1040
1041 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1042 page_start, page_end - 1, &cached_state,
1043 GFP_NOFS);
1044
1045 for (i = 0; i < i_done; i++) {
1046 clear_page_dirty_for_io(pages[i]);
1047 ClearPageChecked(pages[i]);
1048 set_page_extent_mapped(pages[i]);
1049 set_page_dirty(pages[i]);
1050 unlock_page(pages[i]);
1051 page_cache_release(pages[i]);
1052 }
1053 return i_done;
1054 out:
1055 for (i = 0; i < i_done; i++) {
1056 unlock_page(pages[i]);
1057 page_cache_release(pages[i]);
1058 }
1059 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1060 return ret;
1061
1062 }
1063
1064 int btrfs_defrag_file(struct inode *inode, struct file *file,
1065 struct btrfs_ioctl_defrag_range_args *range,
1066 u64 newer_than, unsigned long max_to_defrag)
1067 {
1068 struct btrfs_root *root = BTRFS_I(inode)->root;
1069 struct file_ra_state *ra = NULL;
1070 unsigned long last_index;
1071 u64 isize = i_size_read(inode);
1072 u64 last_len = 0;
1073 u64 skip = 0;
1074 u64 defrag_end = 0;
1075 u64 newer_off = range->start;
1076 unsigned long i;
1077 unsigned long ra_index = 0;
1078 int ret;
1079 int defrag_count = 0;
1080 int compress_type = BTRFS_COMPRESS_ZLIB;
1081 int extent_thresh = range->extent_thresh;
1082 int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1083 int cluster = max_cluster;
1084 u64 new_align = ~((u64)128 * 1024 - 1);
1085 struct page **pages = NULL;
1086
1087 if (extent_thresh == 0)
1088 extent_thresh = 256 * 1024;
1089
1090 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1091 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1092 return -EINVAL;
1093 if (range->compress_type)
1094 compress_type = range->compress_type;
1095 }
1096
1097 if (isize == 0)
1098 return 0;
1099
1100 /*
1101 * if we were not given a file, allocate a readahead
1102 * context
1103 */
1104 if (!file) {
1105 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1106 if (!ra)
1107 return -ENOMEM;
1108 file_ra_state_init(ra, inode->i_mapping);
1109 } else {
1110 ra = &file->f_ra;
1111 }
1112
1113 pages = kmalloc(sizeof(struct page *) * max_cluster,
1114 GFP_NOFS);
1115 if (!pages) {
1116 ret = -ENOMEM;
1117 goto out_ra;
1118 }
1119
1120 /* find the last page to defrag */
1121 if (range->start + range->len > range->start) {
1122 last_index = min_t(u64, isize - 1,
1123 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1124 } else {
1125 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1126 }
1127
1128 if (newer_than) {
1129 ret = find_new_extents(root, inode, newer_than,
1130 &newer_off, 64 * 1024);
1131 if (!ret) {
1132 range->start = newer_off;
1133 /*
1134 * we always align our defrag to help keep
1135 * the extents in the file evenly spaced
1136 */
1137 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1138 } else
1139 goto out_ra;
1140 } else {
1141 i = range->start >> PAGE_CACHE_SHIFT;
1142 }
1143 if (!max_to_defrag)
1144 max_to_defrag = last_index + 1;
1145
1146 /*
1147 * make writeback starts from i, so the defrag range can be
1148 * written sequentially.
1149 */
1150 if (i < inode->i_mapping->writeback_index)
1151 inode->i_mapping->writeback_index = i;
1152
1153 while (i <= last_index && defrag_count < max_to_defrag &&
1154 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1155 PAGE_CACHE_SHIFT)) {
1156 /*
1157 * make sure we stop running if someone unmounts
1158 * the FS
1159 */
1160 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1161 break;
1162
1163 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1164 extent_thresh, &last_len, &skip,
1165 &defrag_end, range->flags &
1166 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1167 unsigned long next;
1168 /*
1169 * the should_defrag function tells us how much to skip
1170 * bump our counter by the suggested amount
1171 */
1172 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1173 i = max(i + 1, next);
1174 continue;
1175 }
1176
1177 if (!newer_than) {
1178 cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1179 PAGE_CACHE_SHIFT) - i;
1180 cluster = min(cluster, max_cluster);
1181 } else {
1182 cluster = max_cluster;
1183 }
1184
1185 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1186 BTRFS_I(inode)->force_compress = compress_type;
1187
1188 if (i + cluster > ra_index) {
1189 ra_index = max(i, ra_index);
1190 btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1191 cluster);
1192 ra_index += max_cluster;
1193 }
1194
1195 mutex_lock(&inode->i_mutex);
1196 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1197 if (ret < 0) {
1198 mutex_unlock(&inode->i_mutex);
1199 goto out_ra;
1200 }
1201
1202 defrag_count += ret;
1203 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
1204 mutex_unlock(&inode->i_mutex);
1205
1206 if (newer_than) {
1207 if (newer_off == (u64)-1)
1208 break;
1209
1210 if (ret > 0)
1211 i += ret;
1212
1213 newer_off = max(newer_off + 1,
1214 (u64)i << PAGE_CACHE_SHIFT);
1215
1216 ret = find_new_extents(root, inode,
1217 newer_than, &newer_off,
1218 64 * 1024);
1219 if (!ret) {
1220 range->start = newer_off;
1221 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1222 } else {
1223 break;
1224 }
1225 } else {
1226 if (ret > 0) {
1227 i += ret;
1228 last_len += ret << PAGE_CACHE_SHIFT;
1229 } else {
1230 i++;
1231 last_len = 0;
1232 }
1233 }
1234 }
1235
1236 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1237 filemap_flush(inode->i_mapping);
1238
1239 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1240 /* the filemap_flush will queue IO into the worker threads, but
1241 * we have to make sure the IO is actually started and that
1242 * ordered extents get created before we return
1243 */
1244 atomic_inc(&root->fs_info->async_submit_draining);
1245 while (atomic_read(&root->fs_info->nr_async_submits) ||
1246 atomic_read(&root->fs_info->async_delalloc_pages)) {
1247 wait_event(root->fs_info->async_submit_wait,
1248 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1249 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1250 }
1251 atomic_dec(&root->fs_info->async_submit_draining);
1252
1253 mutex_lock(&inode->i_mutex);
1254 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1255 mutex_unlock(&inode->i_mutex);
1256 }
1257
1258 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1259 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1260 }
1261
1262 ret = defrag_count;
1263
1264 out_ra:
1265 if (!file)
1266 kfree(ra);
1267 kfree(pages);
1268 return ret;
1269 }
1270
1271 static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
1272 void __user *arg)
1273 {
1274 u64 new_size;
1275 u64 old_size;
1276 u64 devid = 1;
1277 struct btrfs_ioctl_vol_args *vol_args;
1278 struct btrfs_trans_handle *trans;
1279 struct btrfs_device *device = NULL;
1280 char *sizestr;
1281 char *devstr = NULL;
1282 int ret = 0;
1283 int mod = 0;
1284
1285 if (root->fs_info->sb->s_flags & MS_RDONLY)
1286 return -EROFS;
1287
1288 if (!capable(CAP_SYS_ADMIN))
1289 return -EPERM;
1290
1291 mutex_lock(&root->fs_info->volume_mutex);
1292 if (root->fs_info->balance_ctl) {
1293 printk(KERN_INFO "btrfs: balance in progress\n");
1294 ret = -EINVAL;
1295 goto out;
1296 }
1297
1298 vol_args = memdup_user(arg, sizeof(*vol_args));
1299 if (IS_ERR(vol_args)) {
1300 ret = PTR_ERR(vol_args);
1301 goto out;
1302 }
1303
1304 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1305
1306 sizestr = vol_args->name;
1307 devstr = strchr(sizestr, ':');
1308 if (devstr) {
1309 char *end;
1310 sizestr = devstr + 1;
1311 *devstr = '\0';
1312 devstr = vol_args->name;
1313 devid = simple_strtoull(devstr, &end, 10);
1314 printk(KERN_INFO "btrfs: resizing devid %llu\n",
1315 (unsigned long long)devid);
1316 }
1317 device = btrfs_find_device(root, devid, NULL, NULL);
1318 if (!device) {
1319 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n",
1320 (unsigned long long)devid);
1321 ret = -EINVAL;
1322 goto out_free;
1323 }
1324 if (device->fs_devices && device->fs_devices->seeding) {
1325 printk(KERN_INFO "btrfs: resizer unable to apply on "
1326 "seeding device %llu\n",
1327 (unsigned long long)devid);
1328 ret = -EINVAL;
1329 goto out_free;
1330 }
1331
1332 if (!strcmp(sizestr, "max"))
1333 new_size = device->bdev->bd_inode->i_size;
1334 else {
1335 if (sizestr[0] == '-') {
1336 mod = -1;
1337 sizestr++;
1338 } else if (sizestr[0] == '+') {
1339 mod = 1;
1340 sizestr++;
1341 }
1342 new_size = memparse(sizestr, NULL);
1343 if (new_size == 0) {
1344 ret = -EINVAL;
1345 goto out_free;
1346 }
1347 }
1348
1349 old_size = device->total_bytes;
1350
1351 if (mod < 0) {
1352 if (new_size > old_size) {
1353 ret = -EINVAL;
1354 goto out_free;
1355 }
1356 new_size = old_size - new_size;
1357 } else if (mod > 0) {
1358 new_size = old_size + new_size;
1359 }
1360
1361 if (new_size < 256 * 1024 * 1024) {
1362 ret = -EINVAL;
1363 goto out_free;
1364 }
1365 if (new_size > device->bdev->bd_inode->i_size) {
1366 ret = -EFBIG;
1367 goto out_free;
1368 }
1369
1370 do_div(new_size, root->sectorsize);
1371 new_size *= root->sectorsize;
1372
1373 printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n",
1374 rcu_str_deref(device->name),
1375 (unsigned long long)new_size);
1376
1377 if (new_size > old_size) {
1378 trans = btrfs_start_transaction(root, 0);
1379 if (IS_ERR(trans)) {
1380 ret = PTR_ERR(trans);
1381 goto out_free;
1382 }
1383 ret = btrfs_grow_device(trans, device, new_size);
1384 btrfs_commit_transaction(trans, root);
1385 } else if (new_size < old_size) {
1386 ret = btrfs_shrink_device(device, new_size);
1387 }
1388
1389 out_free:
1390 kfree(vol_args);
1391 out:
1392 mutex_unlock(&root->fs_info->volume_mutex);
1393 return ret;
1394 }
1395
1396 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1397 char *name, unsigned long fd, int subvol,
1398 u64 *transid, bool readonly,
1399 struct btrfs_qgroup_inherit **inherit)
1400 {
1401 struct file *src_file;
1402 int namelen;
1403 int ret = 0;
1404
1405 ret = mnt_want_write_file(file);
1406 if (ret)
1407 goto out;
1408
1409 namelen = strlen(name);
1410 if (strchr(name, '/')) {
1411 ret = -EINVAL;
1412 goto out_drop_write;
1413 }
1414
1415 if (name[0] == '.' &&
1416 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1417 ret = -EEXIST;
1418 goto out_drop_write;
1419 }
1420
1421 if (subvol) {
1422 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1423 NULL, transid, readonly, inherit);
1424 } else {
1425 struct inode *src_inode;
1426 src_file = fget(fd);
1427 if (!src_file) {
1428 ret = -EINVAL;
1429 goto out_drop_write;
1430 }
1431
1432 src_inode = src_file->f_path.dentry->d_inode;
1433 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1434 printk(KERN_INFO "btrfs: Snapshot src from "
1435 "another FS\n");
1436 ret = -EINVAL;
1437 fput(src_file);
1438 goto out_drop_write;
1439 }
1440 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1441 BTRFS_I(src_inode)->root,
1442 transid, readonly, inherit);
1443 fput(src_file);
1444 }
1445 out_drop_write:
1446 mnt_drop_write_file(file);
1447 out:
1448 return ret;
1449 }
1450
1451 static noinline int btrfs_ioctl_snap_create(struct file *file,
1452 void __user *arg, int subvol)
1453 {
1454 struct btrfs_ioctl_vol_args *vol_args;
1455 int ret;
1456
1457 vol_args = memdup_user(arg, sizeof(*vol_args));
1458 if (IS_ERR(vol_args))
1459 return PTR_ERR(vol_args);
1460 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1461
1462 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1463 vol_args->fd, subvol,
1464 NULL, false, NULL);
1465
1466 kfree(vol_args);
1467 return ret;
1468 }
1469
1470 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1471 void __user *arg, int subvol)
1472 {
1473 struct btrfs_ioctl_vol_args_v2 *vol_args;
1474 int ret;
1475 u64 transid = 0;
1476 u64 *ptr = NULL;
1477 bool readonly = false;
1478 struct btrfs_qgroup_inherit *inherit = NULL;
1479
1480 vol_args = memdup_user(arg, sizeof(*vol_args));
1481 if (IS_ERR(vol_args))
1482 return PTR_ERR(vol_args);
1483 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1484
1485 if (vol_args->flags &
1486 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1487 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1488 ret = -EOPNOTSUPP;
1489 goto out;
1490 }
1491
1492 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1493 ptr = &transid;
1494 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1495 readonly = true;
1496 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1497 if (vol_args->size > PAGE_CACHE_SIZE) {
1498 ret = -EINVAL;
1499 goto out;
1500 }
1501 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1502 if (IS_ERR(inherit)) {
1503 ret = PTR_ERR(inherit);
1504 goto out;
1505 }
1506 }
1507
1508 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1509 vol_args->fd, subvol, ptr,
1510 readonly, &inherit);
1511
1512 if (ret == 0 && ptr &&
1513 copy_to_user(arg +
1514 offsetof(struct btrfs_ioctl_vol_args_v2,
1515 transid), ptr, sizeof(*ptr)))
1516 ret = -EFAULT;
1517 out:
1518 kfree(vol_args);
1519 kfree(inherit);
1520 return ret;
1521 }
1522
1523 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1524 void __user *arg)
1525 {
1526 struct inode *inode = fdentry(file)->d_inode;
1527 struct btrfs_root *root = BTRFS_I(inode)->root;
1528 int ret = 0;
1529 u64 flags = 0;
1530
1531 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1532 return -EINVAL;
1533
1534 down_read(&root->fs_info->subvol_sem);
1535 if (btrfs_root_readonly(root))
1536 flags |= BTRFS_SUBVOL_RDONLY;
1537 up_read(&root->fs_info->subvol_sem);
1538
1539 if (copy_to_user(arg, &flags, sizeof(flags)))
1540 ret = -EFAULT;
1541
1542 return ret;
1543 }
1544
1545 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1546 void __user *arg)
1547 {
1548 struct inode *inode = fdentry(file)->d_inode;
1549 struct btrfs_root *root = BTRFS_I(inode)->root;
1550 struct btrfs_trans_handle *trans;
1551 u64 root_flags;
1552 u64 flags;
1553 int ret = 0;
1554
1555 ret = mnt_want_write_file(file);
1556 if (ret)
1557 goto out;
1558
1559 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1560 ret = -EINVAL;
1561 goto out_drop_write;
1562 }
1563
1564 if (copy_from_user(&flags, arg, sizeof(flags))) {
1565 ret = -EFAULT;
1566 goto out_drop_write;
1567 }
1568
1569 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1570 ret = -EINVAL;
1571 goto out_drop_write;
1572 }
1573
1574 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1575 ret = -EOPNOTSUPP;
1576 goto out_drop_write;
1577 }
1578
1579 if (!inode_owner_or_capable(inode)) {
1580 ret = -EACCES;
1581 goto out_drop_write;
1582 }
1583
1584 down_write(&root->fs_info->subvol_sem);
1585
1586 /* nothing to do */
1587 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1588 goto out_drop_sem;
1589
1590 root_flags = btrfs_root_flags(&root->root_item);
1591 if (flags & BTRFS_SUBVOL_RDONLY)
1592 btrfs_set_root_flags(&root->root_item,
1593 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1594 else
1595 btrfs_set_root_flags(&root->root_item,
1596 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1597
1598 trans = btrfs_start_transaction(root, 1);
1599 if (IS_ERR(trans)) {
1600 ret = PTR_ERR(trans);
1601 goto out_reset;
1602 }
1603
1604 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1605 &root->root_key, &root->root_item);
1606
1607 btrfs_commit_transaction(trans, root);
1608 out_reset:
1609 if (ret)
1610 btrfs_set_root_flags(&root->root_item, root_flags);
1611 out_drop_sem:
1612 up_write(&root->fs_info->subvol_sem);
1613 out_drop_write:
1614 mnt_drop_write_file(file);
1615 out:
1616 return ret;
1617 }
1618
1619 /*
1620 * helper to check if the subvolume references other subvolumes
1621 */
1622 static noinline int may_destroy_subvol(struct btrfs_root *root)
1623 {
1624 struct btrfs_path *path;
1625 struct btrfs_key key;
1626 int ret;
1627
1628 path = btrfs_alloc_path();
1629 if (!path)
1630 return -ENOMEM;
1631
1632 key.objectid = root->root_key.objectid;
1633 key.type = BTRFS_ROOT_REF_KEY;
1634 key.offset = (u64)-1;
1635
1636 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1637 &key, path, 0, 0);
1638 if (ret < 0)
1639 goto out;
1640 BUG_ON(ret == 0);
1641
1642 ret = 0;
1643 if (path->slots[0] > 0) {
1644 path->slots[0]--;
1645 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1646 if (key.objectid == root->root_key.objectid &&
1647 key.type == BTRFS_ROOT_REF_KEY)
1648 ret = -ENOTEMPTY;
1649 }
1650 out:
1651 btrfs_free_path(path);
1652 return ret;
1653 }
1654
1655 static noinline int key_in_sk(struct btrfs_key *key,
1656 struct btrfs_ioctl_search_key *sk)
1657 {
1658 struct btrfs_key test;
1659 int ret;
1660
1661 test.objectid = sk->min_objectid;
1662 test.type = sk->min_type;
1663 test.offset = sk->min_offset;
1664
1665 ret = btrfs_comp_cpu_keys(key, &test);
1666 if (ret < 0)
1667 return 0;
1668
1669 test.objectid = sk->max_objectid;
1670 test.type = sk->max_type;
1671 test.offset = sk->max_offset;
1672
1673 ret = btrfs_comp_cpu_keys(key, &test);
1674 if (ret > 0)
1675 return 0;
1676 return 1;
1677 }
1678
1679 static noinline int copy_to_sk(struct btrfs_root *root,
1680 struct btrfs_path *path,
1681 struct btrfs_key *key,
1682 struct btrfs_ioctl_search_key *sk,
1683 char *buf,
1684 unsigned long *sk_offset,
1685 int *num_found)
1686 {
1687 u64 found_transid;
1688 struct extent_buffer *leaf;
1689 struct btrfs_ioctl_search_header sh;
1690 unsigned long item_off;
1691 unsigned long item_len;
1692 int nritems;
1693 int i;
1694 int slot;
1695 int ret = 0;
1696
1697 leaf = path->nodes[0];
1698 slot = path->slots[0];
1699 nritems = btrfs_header_nritems(leaf);
1700
1701 if (btrfs_header_generation(leaf) > sk->max_transid) {
1702 i = nritems;
1703 goto advance_key;
1704 }
1705 found_transid = btrfs_header_generation(leaf);
1706
1707 for (i = slot; i < nritems; i++) {
1708 item_off = btrfs_item_ptr_offset(leaf, i);
1709 item_len = btrfs_item_size_nr(leaf, i);
1710
1711 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1712 item_len = 0;
1713
1714 if (sizeof(sh) + item_len + *sk_offset >
1715 BTRFS_SEARCH_ARGS_BUFSIZE) {
1716 ret = 1;
1717 goto overflow;
1718 }
1719
1720 btrfs_item_key_to_cpu(leaf, key, i);
1721 if (!key_in_sk(key, sk))
1722 continue;
1723
1724 sh.objectid = key->objectid;
1725 sh.offset = key->offset;
1726 sh.type = key->type;
1727 sh.len = item_len;
1728 sh.transid = found_transid;
1729
1730 /* copy search result header */
1731 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1732 *sk_offset += sizeof(sh);
1733
1734 if (item_len) {
1735 char *p = buf + *sk_offset;
1736 /* copy the item */
1737 read_extent_buffer(leaf, p,
1738 item_off, item_len);
1739 *sk_offset += item_len;
1740 }
1741 (*num_found)++;
1742
1743 if (*num_found >= sk->nr_items)
1744 break;
1745 }
1746 advance_key:
1747 ret = 0;
1748 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1749 key->offset++;
1750 else if (key->type < (u8)-1 && key->type < sk->max_type) {
1751 key->offset = 0;
1752 key->type++;
1753 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1754 key->offset = 0;
1755 key->type = 0;
1756 key->objectid++;
1757 } else
1758 ret = 1;
1759 overflow:
1760 return ret;
1761 }
1762
1763 static noinline int search_ioctl(struct inode *inode,
1764 struct btrfs_ioctl_search_args *args)
1765 {
1766 struct btrfs_root *root;
1767 struct btrfs_key key;
1768 struct btrfs_key max_key;
1769 struct btrfs_path *path;
1770 struct btrfs_ioctl_search_key *sk = &args->key;
1771 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1772 int ret;
1773 int num_found = 0;
1774 unsigned long sk_offset = 0;
1775
1776 path = btrfs_alloc_path();
1777 if (!path)
1778 return -ENOMEM;
1779
1780 if (sk->tree_id == 0) {
1781 /* search the root of the inode that was passed */
1782 root = BTRFS_I(inode)->root;
1783 } else {
1784 key.objectid = sk->tree_id;
1785 key.type = BTRFS_ROOT_ITEM_KEY;
1786 key.offset = (u64)-1;
1787 root = btrfs_read_fs_root_no_name(info, &key);
1788 if (IS_ERR(root)) {
1789 printk(KERN_ERR "could not find root %llu\n",
1790 sk->tree_id);
1791 btrfs_free_path(path);
1792 return -ENOENT;
1793 }
1794 }
1795
1796 key.objectid = sk->min_objectid;
1797 key.type = sk->min_type;
1798 key.offset = sk->min_offset;
1799
1800 max_key.objectid = sk->max_objectid;
1801 max_key.type = sk->max_type;
1802 max_key.offset = sk->max_offset;
1803
1804 path->keep_locks = 1;
1805
1806 while(1) {
1807 ret = btrfs_search_forward(root, &key, &max_key, path, 0,
1808 sk->min_transid);
1809 if (ret != 0) {
1810 if (ret > 0)
1811 ret = 0;
1812 goto err;
1813 }
1814 ret = copy_to_sk(root, path, &key, sk, args->buf,
1815 &sk_offset, &num_found);
1816 btrfs_release_path(path);
1817 if (ret || num_found >= sk->nr_items)
1818 break;
1819
1820 }
1821 ret = 0;
1822 err:
1823 sk->nr_items = num_found;
1824 btrfs_free_path(path);
1825 return ret;
1826 }
1827
1828 static noinline int btrfs_ioctl_tree_search(struct file *file,
1829 void __user *argp)
1830 {
1831 struct btrfs_ioctl_search_args *args;
1832 struct inode *inode;
1833 int ret;
1834
1835 if (!capable(CAP_SYS_ADMIN))
1836 return -EPERM;
1837
1838 args = memdup_user(argp, sizeof(*args));
1839 if (IS_ERR(args))
1840 return PTR_ERR(args);
1841
1842 inode = fdentry(file)->d_inode;
1843 ret = search_ioctl(inode, args);
1844 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1845 ret = -EFAULT;
1846 kfree(args);
1847 return ret;
1848 }
1849
1850 /*
1851 * Search INODE_REFs to identify path name of 'dirid' directory
1852 * in a 'tree_id' tree. and sets path name to 'name'.
1853 */
1854 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1855 u64 tree_id, u64 dirid, char *name)
1856 {
1857 struct btrfs_root *root;
1858 struct btrfs_key key;
1859 char *ptr;
1860 int ret = -1;
1861 int slot;
1862 int len;
1863 int total_len = 0;
1864 struct btrfs_inode_ref *iref;
1865 struct extent_buffer *l;
1866 struct btrfs_path *path;
1867
1868 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1869 name[0]='\0';
1870 return 0;
1871 }
1872
1873 path = btrfs_alloc_path();
1874 if (!path)
1875 return -ENOMEM;
1876
1877 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1878
1879 key.objectid = tree_id;
1880 key.type = BTRFS_ROOT_ITEM_KEY;
1881 key.offset = (u64)-1;
1882 root = btrfs_read_fs_root_no_name(info, &key);
1883 if (IS_ERR(root)) {
1884 printk(KERN_ERR "could not find root %llu\n", tree_id);
1885 ret = -ENOENT;
1886 goto out;
1887 }
1888
1889 key.objectid = dirid;
1890 key.type = BTRFS_INODE_REF_KEY;
1891 key.offset = (u64)-1;
1892
1893 while(1) {
1894 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1895 if (ret < 0)
1896 goto out;
1897
1898 l = path->nodes[0];
1899 slot = path->slots[0];
1900 if (ret > 0 && slot > 0)
1901 slot--;
1902 btrfs_item_key_to_cpu(l, &key, slot);
1903
1904 if (ret > 0 && (key.objectid != dirid ||
1905 key.type != BTRFS_INODE_REF_KEY)) {
1906 ret = -ENOENT;
1907 goto out;
1908 }
1909
1910 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1911 len = btrfs_inode_ref_name_len(l, iref);
1912 ptr -= len + 1;
1913 total_len += len + 1;
1914 if (ptr < name)
1915 goto out;
1916
1917 *(ptr + len) = '/';
1918 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1919
1920 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1921 break;
1922
1923 btrfs_release_path(path);
1924 key.objectid = key.offset;
1925 key.offset = (u64)-1;
1926 dirid = key.objectid;
1927 }
1928 if (ptr < name)
1929 goto out;
1930 memmove(name, ptr, total_len);
1931 name[total_len]='\0';
1932 ret = 0;
1933 out:
1934 btrfs_free_path(path);
1935 return ret;
1936 }
1937
1938 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
1939 void __user *argp)
1940 {
1941 struct btrfs_ioctl_ino_lookup_args *args;
1942 struct inode *inode;
1943 int ret;
1944
1945 if (!capable(CAP_SYS_ADMIN))
1946 return -EPERM;
1947
1948 args = memdup_user(argp, sizeof(*args));
1949 if (IS_ERR(args))
1950 return PTR_ERR(args);
1951
1952 inode = fdentry(file)->d_inode;
1953
1954 if (args->treeid == 0)
1955 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
1956
1957 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
1958 args->treeid, args->objectid,
1959 args->name);
1960
1961 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1962 ret = -EFAULT;
1963
1964 kfree(args);
1965 return ret;
1966 }
1967
1968 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
1969 void __user *arg)
1970 {
1971 struct dentry *parent = fdentry(file);
1972 struct dentry *dentry;
1973 struct inode *dir = parent->d_inode;
1974 struct inode *inode;
1975 struct btrfs_root *root = BTRFS_I(dir)->root;
1976 struct btrfs_root *dest = NULL;
1977 struct btrfs_ioctl_vol_args *vol_args;
1978 struct btrfs_trans_handle *trans;
1979 int namelen;
1980 int ret;
1981 int err = 0;
1982
1983 vol_args = memdup_user(arg, sizeof(*vol_args));
1984 if (IS_ERR(vol_args))
1985 return PTR_ERR(vol_args);
1986
1987 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1988 namelen = strlen(vol_args->name);
1989 if (strchr(vol_args->name, '/') ||
1990 strncmp(vol_args->name, "..", namelen) == 0) {
1991 err = -EINVAL;
1992 goto out;
1993 }
1994
1995 err = mnt_want_write_file(file);
1996 if (err)
1997 goto out;
1998
1999 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
2000 dentry = lookup_one_len(vol_args->name, parent, namelen);
2001 if (IS_ERR(dentry)) {
2002 err = PTR_ERR(dentry);
2003 goto out_unlock_dir;
2004 }
2005
2006 if (!dentry->d_inode) {
2007 err = -ENOENT;
2008 goto out_dput;
2009 }
2010
2011 inode = dentry->d_inode;
2012 dest = BTRFS_I(inode)->root;
2013 if (!capable(CAP_SYS_ADMIN)){
2014 /*
2015 * Regular user. Only allow this with a special mount
2016 * option, when the user has write+exec access to the
2017 * subvol root, and when rmdir(2) would have been
2018 * allowed.
2019 *
2020 * Note that this is _not_ check that the subvol is
2021 * empty or doesn't contain data that we wouldn't
2022 * otherwise be able to delete.
2023 *
2024 * Users who want to delete empty subvols should try
2025 * rmdir(2).
2026 */
2027 err = -EPERM;
2028 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2029 goto out_dput;
2030
2031 /*
2032 * Do not allow deletion if the parent dir is the same
2033 * as the dir to be deleted. That means the ioctl
2034 * must be called on the dentry referencing the root
2035 * of the subvol, not a random directory contained
2036 * within it.
2037 */
2038 err = -EINVAL;
2039 if (root == dest)
2040 goto out_dput;
2041
2042 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2043 if (err)
2044 goto out_dput;
2045
2046 /* check if subvolume may be deleted by a non-root user */
2047 err = btrfs_may_delete(dir, dentry, 1);
2048 if (err)
2049 goto out_dput;
2050 }
2051
2052 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2053 err = -EINVAL;
2054 goto out_dput;
2055 }
2056
2057 mutex_lock(&inode->i_mutex);
2058 err = d_invalidate(dentry);
2059 if (err)
2060 goto out_unlock;
2061
2062 down_write(&root->fs_info->subvol_sem);
2063
2064 err = may_destroy_subvol(dest);
2065 if (err)
2066 goto out_up_write;
2067
2068 trans = btrfs_start_transaction(root, 0);
2069 if (IS_ERR(trans)) {
2070 err = PTR_ERR(trans);
2071 goto out_up_write;
2072 }
2073 trans->block_rsv = &root->fs_info->global_block_rsv;
2074
2075 ret = btrfs_unlink_subvol(trans, root, dir,
2076 dest->root_key.objectid,
2077 dentry->d_name.name,
2078 dentry->d_name.len);
2079 if (ret) {
2080 err = ret;
2081 btrfs_abort_transaction(trans, root, ret);
2082 goto out_end_trans;
2083 }
2084
2085 btrfs_record_root_in_trans(trans, dest);
2086
2087 memset(&dest->root_item.drop_progress, 0,
2088 sizeof(dest->root_item.drop_progress));
2089 dest->root_item.drop_level = 0;
2090 btrfs_set_root_refs(&dest->root_item, 0);
2091
2092 if (!xchg(&dest->orphan_item_inserted, 1)) {
2093 ret = btrfs_insert_orphan_item(trans,
2094 root->fs_info->tree_root,
2095 dest->root_key.objectid);
2096 if (ret) {
2097 btrfs_abort_transaction(trans, root, ret);
2098 err = ret;
2099 goto out_end_trans;
2100 }
2101 }
2102 out_end_trans:
2103 ret = btrfs_end_transaction(trans, root);
2104 if (ret && !err)
2105 err = ret;
2106 inode->i_flags |= S_DEAD;
2107 out_up_write:
2108 up_write(&root->fs_info->subvol_sem);
2109 out_unlock:
2110 mutex_unlock(&inode->i_mutex);
2111 if (!err) {
2112 shrink_dcache_sb(root->fs_info->sb);
2113 btrfs_invalidate_inodes(dest);
2114 d_delete(dentry);
2115 }
2116 out_dput:
2117 dput(dentry);
2118 out_unlock_dir:
2119 mutex_unlock(&dir->i_mutex);
2120 mnt_drop_write_file(file);
2121 out:
2122 kfree(vol_args);
2123 return err;
2124 }
2125
2126 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2127 {
2128 struct inode *inode = fdentry(file)->d_inode;
2129 struct btrfs_root *root = BTRFS_I(inode)->root;
2130 struct btrfs_ioctl_defrag_range_args *range;
2131 int ret;
2132
2133 if (btrfs_root_readonly(root))
2134 return -EROFS;
2135
2136 ret = mnt_want_write_file(file);
2137 if (ret)
2138 return ret;
2139
2140 switch (inode->i_mode & S_IFMT) {
2141 case S_IFDIR:
2142 if (!capable(CAP_SYS_ADMIN)) {
2143 ret = -EPERM;
2144 goto out;
2145 }
2146 ret = btrfs_defrag_root(root, 0);
2147 if (ret)
2148 goto out;
2149 ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
2150 break;
2151 case S_IFREG:
2152 if (!(file->f_mode & FMODE_WRITE)) {
2153 ret = -EINVAL;
2154 goto out;
2155 }
2156
2157 range = kzalloc(sizeof(*range), GFP_KERNEL);
2158 if (!range) {
2159 ret = -ENOMEM;
2160 goto out;
2161 }
2162
2163 if (argp) {
2164 if (copy_from_user(range, argp,
2165 sizeof(*range))) {
2166 ret = -EFAULT;
2167 kfree(range);
2168 goto out;
2169 }
2170 /* compression requires us to start the IO */
2171 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2172 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2173 range->extent_thresh = (u32)-1;
2174 }
2175 } else {
2176 /* the rest are all set to zero by kzalloc */
2177 range->len = (u64)-1;
2178 }
2179 ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
2180 range, 0, 0);
2181 if (ret > 0)
2182 ret = 0;
2183 kfree(range);
2184 break;
2185 default:
2186 ret = -EINVAL;
2187 }
2188 out:
2189 mnt_drop_write_file(file);
2190 return ret;
2191 }
2192
2193 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2194 {
2195 struct btrfs_ioctl_vol_args *vol_args;
2196 int ret;
2197
2198 if (!capable(CAP_SYS_ADMIN))
2199 return -EPERM;
2200
2201 mutex_lock(&root->fs_info->volume_mutex);
2202 if (root->fs_info->balance_ctl) {
2203 printk(KERN_INFO "btrfs: balance in progress\n");
2204 ret = -EINVAL;
2205 goto out;
2206 }
2207
2208 vol_args = memdup_user(arg, sizeof(*vol_args));
2209 if (IS_ERR(vol_args)) {
2210 ret = PTR_ERR(vol_args);
2211 goto out;
2212 }
2213
2214 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2215 ret = btrfs_init_new_device(root, vol_args->name);
2216
2217 kfree(vol_args);
2218 out:
2219 mutex_unlock(&root->fs_info->volume_mutex);
2220 return ret;
2221 }
2222
2223 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
2224 {
2225 struct btrfs_ioctl_vol_args *vol_args;
2226 int ret;
2227
2228 if (!capable(CAP_SYS_ADMIN))
2229 return -EPERM;
2230
2231 if (root->fs_info->sb->s_flags & MS_RDONLY)
2232 return -EROFS;
2233
2234 mutex_lock(&root->fs_info->volume_mutex);
2235 if (root->fs_info->balance_ctl) {
2236 printk(KERN_INFO "btrfs: balance in progress\n");
2237 ret = -EINVAL;
2238 goto out;
2239 }
2240
2241 vol_args = memdup_user(arg, sizeof(*vol_args));
2242 if (IS_ERR(vol_args)) {
2243 ret = PTR_ERR(vol_args);
2244 goto out;
2245 }
2246
2247 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2248 ret = btrfs_rm_device(root, vol_args->name);
2249
2250 kfree(vol_args);
2251 out:
2252 mutex_unlock(&root->fs_info->volume_mutex);
2253 return ret;
2254 }
2255
2256 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2257 {
2258 struct btrfs_ioctl_fs_info_args *fi_args;
2259 struct btrfs_device *device;
2260 struct btrfs_device *next;
2261 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2262 int ret = 0;
2263
2264 if (!capable(CAP_SYS_ADMIN))
2265 return -EPERM;
2266
2267 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2268 if (!fi_args)
2269 return -ENOMEM;
2270
2271 fi_args->num_devices = fs_devices->num_devices;
2272 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2273
2274 mutex_lock(&fs_devices->device_list_mutex);
2275 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2276 if (device->devid > fi_args->max_id)
2277 fi_args->max_id = device->devid;
2278 }
2279 mutex_unlock(&fs_devices->device_list_mutex);
2280
2281 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2282 ret = -EFAULT;
2283
2284 kfree(fi_args);
2285 return ret;
2286 }
2287
2288 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2289 {
2290 struct btrfs_ioctl_dev_info_args *di_args;
2291 struct btrfs_device *dev;
2292 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2293 int ret = 0;
2294 char *s_uuid = NULL;
2295 char empty_uuid[BTRFS_UUID_SIZE] = {0};
2296
2297 if (!capable(CAP_SYS_ADMIN))
2298 return -EPERM;
2299
2300 di_args = memdup_user(arg, sizeof(*di_args));
2301 if (IS_ERR(di_args))
2302 return PTR_ERR(di_args);
2303
2304 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2305 s_uuid = di_args->uuid;
2306
2307 mutex_lock(&fs_devices->device_list_mutex);
2308 dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL);
2309 mutex_unlock(&fs_devices->device_list_mutex);
2310
2311 if (!dev) {
2312 ret = -ENODEV;
2313 goto out;
2314 }
2315
2316 di_args->devid = dev->devid;
2317 di_args->bytes_used = dev->bytes_used;
2318 di_args->total_bytes = dev->total_bytes;
2319 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2320 if (dev->name) {
2321 struct rcu_string *name;
2322
2323 rcu_read_lock();
2324 name = rcu_dereference(dev->name);
2325 strncpy(di_args->path, name->str, sizeof(di_args->path));
2326 rcu_read_unlock();
2327 di_args->path[sizeof(di_args->path) - 1] = 0;
2328 } else {
2329 di_args->path[0] = '\0';
2330 }
2331
2332 out:
2333 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2334 ret = -EFAULT;
2335
2336 kfree(di_args);
2337 return ret;
2338 }
2339
2340 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2341 u64 off, u64 olen, u64 destoff)
2342 {
2343 struct inode *inode = fdentry(file)->d_inode;
2344 struct btrfs_root *root = BTRFS_I(inode)->root;
2345 struct file *src_file;
2346 struct inode *src;
2347 struct btrfs_trans_handle *trans;
2348 struct btrfs_path *path;
2349 struct extent_buffer *leaf;
2350 char *buf;
2351 struct btrfs_key key;
2352 u32 nritems;
2353 int slot;
2354 int ret;
2355 u64 len = olen;
2356 u64 bs = root->fs_info->sb->s_blocksize;
2357
2358 /*
2359 * TODO:
2360 * - split compressed inline extents. annoying: we need to
2361 * decompress into destination's address_space (the file offset
2362 * may change, so source mapping won't do), then recompress (or
2363 * otherwise reinsert) a subrange.
2364 * - allow ranges within the same file to be cloned (provided
2365 * they don't overlap)?
2366 */
2367
2368 /* the destination must be opened for writing */
2369 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2370 return -EINVAL;
2371
2372 if (btrfs_root_readonly(root))
2373 return -EROFS;
2374
2375 ret = mnt_want_write_file(file);
2376 if (ret)
2377 return ret;
2378
2379 src_file = fget(srcfd);
2380 if (!src_file) {
2381 ret = -EBADF;
2382 goto out_drop_write;
2383 }
2384
2385 ret = -EXDEV;
2386 if (src_file->f_path.mnt != file->f_path.mnt)
2387 goto out_fput;
2388
2389 src = src_file->f_dentry->d_inode;
2390
2391 ret = -EINVAL;
2392 if (src == inode)
2393 goto out_fput;
2394
2395 /* the src must be open for reading */
2396 if (!(src_file->f_mode & FMODE_READ))
2397 goto out_fput;
2398
2399 /* don't make the dst file partly checksummed */
2400 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2401 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2402 goto out_fput;
2403
2404 ret = -EISDIR;
2405 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2406 goto out_fput;
2407
2408 ret = -EXDEV;
2409 if (src->i_sb != inode->i_sb)
2410 goto out_fput;
2411
2412 ret = -ENOMEM;
2413 buf = vmalloc(btrfs_level_size(root, 0));
2414 if (!buf)
2415 goto out_fput;
2416
2417 path = btrfs_alloc_path();
2418 if (!path) {
2419 vfree(buf);
2420 goto out_fput;
2421 }
2422 path->reada = 2;
2423
2424 if (inode < src) {
2425 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2426 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2427 } else {
2428 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2429 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2430 }
2431
2432 /* determine range to clone */
2433 ret = -EINVAL;
2434 if (off + len > src->i_size || off + len < off)
2435 goto out_unlock;
2436 if (len == 0)
2437 olen = len = src->i_size - off;
2438 /* if we extend to eof, continue to block boundary */
2439 if (off + len == src->i_size)
2440 len = ALIGN(src->i_size, bs) - off;
2441
2442 /* verify the end result is block aligned */
2443 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2444 !IS_ALIGNED(destoff, bs))
2445 goto out_unlock;
2446
2447 if (destoff > inode->i_size) {
2448 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2449 if (ret)
2450 goto out_unlock;
2451 }
2452
2453 /* truncate page cache pages from target inode range */
2454 truncate_inode_pages_range(&inode->i_data, destoff,
2455 PAGE_CACHE_ALIGN(destoff + len) - 1);
2456
2457 /* do any pending delalloc/csum calc on src, one way or
2458 another, and lock file content */
2459 while (1) {
2460 struct btrfs_ordered_extent *ordered;
2461 lock_extent(&BTRFS_I(src)->io_tree, off, off+len);
2462 ordered = btrfs_lookup_first_ordered_extent(src, off+len);
2463 if (!ordered &&
2464 !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len,
2465 EXTENT_DELALLOC, 0, NULL))
2466 break;
2467 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len);
2468 if (ordered)
2469 btrfs_put_ordered_extent(ordered);
2470 btrfs_wait_ordered_range(src, off, len);
2471 }
2472
2473 /* clone data */
2474 key.objectid = btrfs_ino(src);
2475 key.type = BTRFS_EXTENT_DATA_KEY;
2476 key.offset = 0;
2477
2478 while (1) {
2479 /*
2480 * note the key will change type as we walk through the
2481 * tree.
2482 */
2483 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
2484 0, 0);
2485 if (ret < 0)
2486 goto out;
2487
2488 nritems = btrfs_header_nritems(path->nodes[0]);
2489 if (path->slots[0] >= nritems) {
2490 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
2491 if (ret < 0)
2492 goto out;
2493 if (ret > 0)
2494 break;
2495 nritems = btrfs_header_nritems(path->nodes[0]);
2496 }
2497 leaf = path->nodes[0];
2498 slot = path->slots[0];
2499
2500 btrfs_item_key_to_cpu(leaf, &key, slot);
2501 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2502 key.objectid != btrfs_ino(src))
2503 break;
2504
2505 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2506 struct btrfs_file_extent_item *extent;
2507 int type;
2508 u32 size;
2509 struct btrfs_key new_key;
2510 u64 disko = 0, diskl = 0;
2511 u64 datao = 0, datal = 0;
2512 u8 comp;
2513 u64 endoff;
2514
2515 size = btrfs_item_size_nr(leaf, slot);
2516 read_extent_buffer(leaf, buf,
2517 btrfs_item_ptr_offset(leaf, slot),
2518 size);
2519
2520 extent = btrfs_item_ptr(leaf, slot,
2521 struct btrfs_file_extent_item);
2522 comp = btrfs_file_extent_compression(leaf, extent);
2523 type = btrfs_file_extent_type(leaf, extent);
2524 if (type == BTRFS_FILE_EXTENT_REG ||
2525 type == BTRFS_FILE_EXTENT_PREALLOC) {
2526 disko = btrfs_file_extent_disk_bytenr(leaf,
2527 extent);
2528 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2529 extent);
2530 datao = btrfs_file_extent_offset(leaf, extent);
2531 datal = btrfs_file_extent_num_bytes(leaf,
2532 extent);
2533 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2534 /* take upper bound, may be compressed */
2535 datal = btrfs_file_extent_ram_bytes(leaf,
2536 extent);
2537 }
2538 btrfs_release_path(path);
2539
2540 if (key.offset + datal <= off ||
2541 key.offset >= off+len)
2542 goto next;
2543
2544 memcpy(&new_key, &key, sizeof(new_key));
2545 new_key.objectid = btrfs_ino(inode);
2546 if (off <= key.offset)
2547 new_key.offset = key.offset + destoff - off;
2548 else
2549 new_key.offset = destoff;
2550
2551 /*
2552 * 1 - adjusting old extent (we may have to split it)
2553 * 1 - add new extent
2554 * 1 - inode update
2555 */
2556 trans = btrfs_start_transaction(root, 3);
2557 if (IS_ERR(trans)) {
2558 ret = PTR_ERR(trans);
2559 goto out;
2560 }
2561
2562 if (type == BTRFS_FILE_EXTENT_REG ||
2563 type == BTRFS_FILE_EXTENT_PREALLOC) {
2564 /*
2565 * a | --- range to clone ---| b
2566 * | ------------- extent ------------- |
2567 */
2568
2569 /* substract range b */
2570 if (key.offset + datal > off + len)
2571 datal = off + len - key.offset;
2572
2573 /* substract range a */
2574 if (off > key.offset) {
2575 datao += off - key.offset;
2576 datal -= off - key.offset;
2577 }
2578
2579 ret = btrfs_drop_extents(trans, root, inode,
2580 new_key.offset,
2581 new_key.offset + datal,
2582 1);
2583 if (ret) {
2584 btrfs_abort_transaction(trans, root,
2585 ret);
2586 btrfs_end_transaction(trans, root);
2587 goto out;
2588 }
2589
2590 ret = btrfs_insert_empty_item(trans, root, path,
2591 &new_key, size);
2592 if (ret) {
2593 btrfs_abort_transaction(trans, root,
2594 ret);
2595 btrfs_end_transaction(trans, root);
2596 goto out;
2597 }
2598
2599 leaf = path->nodes[0];
2600 slot = path->slots[0];
2601 write_extent_buffer(leaf, buf,
2602 btrfs_item_ptr_offset(leaf, slot),
2603 size);
2604
2605 extent = btrfs_item_ptr(leaf, slot,
2606 struct btrfs_file_extent_item);
2607
2608 /* disko == 0 means it's a hole */
2609 if (!disko)
2610 datao = 0;
2611
2612 btrfs_set_file_extent_offset(leaf, extent,
2613 datao);
2614 btrfs_set_file_extent_num_bytes(leaf, extent,
2615 datal);
2616 if (disko) {
2617 inode_add_bytes(inode, datal);
2618 ret = btrfs_inc_extent_ref(trans, root,
2619 disko, diskl, 0,
2620 root->root_key.objectid,
2621 btrfs_ino(inode),
2622 new_key.offset - datao,
2623 0);
2624 if (ret) {
2625 btrfs_abort_transaction(trans,
2626 root,
2627 ret);
2628 btrfs_end_transaction(trans,
2629 root);
2630 goto out;
2631
2632 }
2633 }
2634 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2635 u64 skip = 0;
2636 u64 trim = 0;
2637 if (off > key.offset) {
2638 skip = off - key.offset;
2639 new_key.offset += skip;
2640 }
2641
2642 if (key.offset + datal > off+len)
2643 trim = key.offset + datal - (off+len);
2644
2645 if (comp && (skip || trim)) {
2646 ret = -EINVAL;
2647 btrfs_end_transaction(trans, root);
2648 goto out;
2649 }
2650 size -= skip + trim;
2651 datal -= skip + trim;
2652
2653 ret = btrfs_drop_extents(trans, root, inode,
2654 new_key.offset,
2655 new_key.offset + datal,
2656 1);
2657 if (ret) {
2658 btrfs_abort_transaction(trans, root,
2659 ret);
2660 btrfs_end_transaction(trans, root);
2661 goto out;
2662 }
2663
2664 ret = btrfs_insert_empty_item(trans, root, path,
2665 &new_key, size);
2666 if (ret) {
2667 btrfs_abort_transaction(trans, root,
2668 ret);
2669 btrfs_end_transaction(trans, root);
2670 goto out;
2671 }
2672
2673 if (skip) {
2674 u32 start =
2675 btrfs_file_extent_calc_inline_size(0);
2676 memmove(buf+start, buf+start+skip,
2677 datal);
2678 }
2679
2680 leaf = path->nodes[0];
2681 slot = path->slots[0];
2682 write_extent_buffer(leaf, buf,
2683 btrfs_item_ptr_offset(leaf, slot),
2684 size);
2685 inode_add_bytes(inode, datal);
2686 }
2687
2688 btrfs_mark_buffer_dirty(leaf);
2689 btrfs_release_path(path);
2690
2691 inode_inc_iversion(inode);
2692 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2693
2694 /*
2695 * we round up to the block size at eof when
2696 * determining which extents to clone above,
2697 * but shouldn't round up the file size
2698 */
2699 endoff = new_key.offset + datal;
2700 if (endoff > destoff+olen)
2701 endoff = destoff+olen;
2702 if (endoff > inode->i_size)
2703 btrfs_i_size_write(inode, endoff);
2704
2705 ret = btrfs_update_inode(trans, root, inode);
2706 if (ret) {
2707 btrfs_abort_transaction(trans, root, ret);
2708 btrfs_end_transaction(trans, root);
2709 goto out;
2710 }
2711 ret = btrfs_end_transaction(trans, root);
2712 }
2713 next:
2714 btrfs_release_path(path);
2715 key.offset++;
2716 }
2717 ret = 0;
2718 out:
2719 btrfs_release_path(path);
2720 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len);
2721 out_unlock:
2722 mutex_unlock(&src->i_mutex);
2723 mutex_unlock(&inode->i_mutex);
2724 vfree(buf);
2725 btrfs_free_path(path);
2726 out_fput:
2727 fput(src_file);
2728 out_drop_write:
2729 mnt_drop_write_file(file);
2730 return ret;
2731 }
2732
2733 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2734 {
2735 struct btrfs_ioctl_clone_range_args args;
2736
2737 if (copy_from_user(&args, argp, sizeof(args)))
2738 return -EFAULT;
2739 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2740 args.src_length, args.dest_offset);
2741 }
2742
2743 /*
2744 * there are many ways the trans_start and trans_end ioctls can lead
2745 * to deadlocks. They should only be used by applications that
2746 * basically own the machine, and have a very in depth understanding
2747 * of all the possible deadlocks and enospc problems.
2748 */
2749 static long btrfs_ioctl_trans_start(struct file *file)
2750 {
2751 struct inode *inode = fdentry(file)->d_inode;
2752 struct btrfs_root *root = BTRFS_I(inode)->root;
2753 struct btrfs_trans_handle *trans;
2754 int ret;
2755
2756 ret = -EPERM;
2757 if (!capable(CAP_SYS_ADMIN))
2758 goto out;
2759
2760 ret = -EINPROGRESS;
2761 if (file->private_data)
2762 goto out;
2763
2764 ret = -EROFS;
2765 if (btrfs_root_readonly(root))
2766 goto out;
2767
2768 ret = mnt_want_write_file(file);
2769 if (ret)
2770 goto out;
2771
2772 atomic_inc(&root->fs_info->open_ioctl_trans);
2773
2774 ret = -ENOMEM;
2775 trans = btrfs_start_ioctl_transaction(root);
2776 if (IS_ERR(trans))
2777 goto out_drop;
2778
2779 file->private_data = trans;
2780 return 0;
2781
2782 out_drop:
2783 atomic_dec(&root->fs_info->open_ioctl_trans);
2784 mnt_drop_write_file(file);
2785 out:
2786 return ret;
2787 }
2788
2789 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2790 {
2791 struct inode *inode = fdentry(file)->d_inode;
2792 struct btrfs_root *root = BTRFS_I(inode)->root;
2793 struct btrfs_root *new_root;
2794 struct btrfs_dir_item *di;
2795 struct btrfs_trans_handle *trans;
2796 struct btrfs_path *path;
2797 struct btrfs_key location;
2798 struct btrfs_disk_key disk_key;
2799 u64 objectid = 0;
2800 u64 dir_id;
2801
2802 if (!capable(CAP_SYS_ADMIN))
2803 return -EPERM;
2804
2805 if (copy_from_user(&objectid, argp, sizeof(objectid)))
2806 return -EFAULT;
2807
2808 if (!objectid)
2809 objectid = root->root_key.objectid;
2810
2811 location.objectid = objectid;
2812 location.type = BTRFS_ROOT_ITEM_KEY;
2813 location.offset = (u64)-1;
2814
2815 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2816 if (IS_ERR(new_root))
2817 return PTR_ERR(new_root);
2818
2819 if (btrfs_root_refs(&new_root->root_item) == 0)
2820 return -ENOENT;
2821
2822 path = btrfs_alloc_path();
2823 if (!path)
2824 return -ENOMEM;
2825 path->leave_spinning = 1;
2826
2827 trans = btrfs_start_transaction(root, 1);
2828 if (IS_ERR(trans)) {
2829 btrfs_free_path(path);
2830 return PTR_ERR(trans);
2831 }
2832
2833 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
2834 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2835 dir_id, "default", 7, 1);
2836 if (IS_ERR_OR_NULL(di)) {
2837 btrfs_free_path(path);
2838 btrfs_end_transaction(trans, root);
2839 printk(KERN_ERR "Umm, you don't have the default dir item, "
2840 "this isn't going to work\n");
2841 return -ENOENT;
2842 }
2843
2844 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2845 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2846 btrfs_mark_buffer_dirty(path->nodes[0]);
2847 btrfs_free_path(path);
2848
2849 btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
2850 btrfs_end_transaction(trans, root);
2851
2852 return 0;
2853 }
2854
2855 static void get_block_group_info(struct list_head *groups_list,
2856 struct btrfs_ioctl_space_info *space)
2857 {
2858 struct btrfs_block_group_cache *block_group;
2859
2860 space->total_bytes = 0;
2861 space->used_bytes = 0;
2862 space->flags = 0;
2863 list_for_each_entry(block_group, groups_list, list) {
2864 space->flags = block_group->flags;
2865 space->total_bytes += block_group->key.offset;
2866 space->used_bytes +=
2867 btrfs_block_group_used(&block_group->item);
2868 }
2869 }
2870
2871 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
2872 {
2873 struct btrfs_ioctl_space_args space_args;
2874 struct btrfs_ioctl_space_info space;
2875 struct btrfs_ioctl_space_info *dest;
2876 struct btrfs_ioctl_space_info *dest_orig;
2877 struct btrfs_ioctl_space_info __user *user_dest;
2878 struct btrfs_space_info *info;
2879 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2880 BTRFS_BLOCK_GROUP_SYSTEM,
2881 BTRFS_BLOCK_GROUP_METADATA,
2882 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
2883 int num_types = 4;
2884 int alloc_size;
2885 int ret = 0;
2886 u64 slot_count = 0;
2887 int i, c;
2888
2889 if (copy_from_user(&space_args,
2890 (struct btrfs_ioctl_space_args __user *)arg,
2891 sizeof(space_args)))
2892 return -EFAULT;
2893
2894 for (i = 0; i < num_types; i++) {
2895 struct btrfs_space_info *tmp;
2896
2897 info = NULL;
2898 rcu_read_lock();
2899 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2900 list) {
2901 if (tmp->flags == types[i]) {
2902 info = tmp;
2903 break;
2904 }
2905 }
2906 rcu_read_unlock();
2907
2908 if (!info)
2909 continue;
2910
2911 down_read(&info->groups_sem);
2912 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2913 if (!list_empty(&info->block_groups[c]))
2914 slot_count++;
2915 }
2916 up_read(&info->groups_sem);
2917 }
2918
2919 /* space_slots == 0 means they are asking for a count */
2920 if (space_args.space_slots == 0) {
2921 space_args.total_spaces = slot_count;
2922 goto out;
2923 }
2924
2925 slot_count = min_t(u64, space_args.space_slots, slot_count);
2926
2927 alloc_size = sizeof(*dest) * slot_count;
2928
2929 /* we generally have at most 6 or so space infos, one for each raid
2930 * level. So, a whole page should be more than enough for everyone
2931 */
2932 if (alloc_size > PAGE_CACHE_SIZE)
2933 return -ENOMEM;
2934
2935 space_args.total_spaces = 0;
2936 dest = kmalloc(alloc_size, GFP_NOFS);
2937 if (!dest)
2938 return -ENOMEM;
2939 dest_orig = dest;
2940
2941 /* now we have a buffer to copy into */
2942 for (i = 0; i < num_types; i++) {
2943 struct btrfs_space_info *tmp;
2944
2945 if (!slot_count)
2946 break;
2947
2948 info = NULL;
2949 rcu_read_lock();
2950 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2951 list) {
2952 if (tmp->flags == types[i]) {
2953 info = tmp;
2954 break;
2955 }
2956 }
2957 rcu_read_unlock();
2958
2959 if (!info)
2960 continue;
2961 down_read(&info->groups_sem);
2962 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2963 if (!list_empty(&info->block_groups[c])) {
2964 get_block_group_info(&info->block_groups[c],
2965 &space);
2966 memcpy(dest, &space, sizeof(space));
2967 dest++;
2968 space_args.total_spaces++;
2969 slot_count--;
2970 }
2971 if (!slot_count)
2972 break;
2973 }
2974 up_read(&info->groups_sem);
2975 }
2976
2977 user_dest = (struct btrfs_ioctl_space_info __user *)
2978 (arg + sizeof(struct btrfs_ioctl_space_args));
2979
2980 if (copy_to_user(user_dest, dest_orig, alloc_size))
2981 ret = -EFAULT;
2982
2983 kfree(dest_orig);
2984 out:
2985 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
2986 ret = -EFAULT;
2987
2988 return ret;
2989 }
2990
2991 /*
2992 * there are many ways the trans_start and trans_end ioctls can lead
2993 * to deadlocks. They should only be used by applications that
2994 * basically own the machine, and have a very in depth understanding
2995 * of all the possible deadlocks and enospc problems.
2996 */
2997 long btrfs_ioctl_trans_end(struct file *file)
2998 {
2999 struct inode *inode = fdentry(file)->d_inode;
3000 struct btrfs_root *root = BTRFS_I(inode)->root;
3001 struct btrfs_trans_handle *trans;
3002
3003 trans = file->private_data;
3004 if (!trans)
3005 return -EINVAL;
3006 file->private_data = NULL;
3007
3008 btrfs_end_transaction(trans, root);
3009
3010 atomic_dec(&root->fs_info->open_ioctl_trans);
3011
3012 mnt_drop_write_file(file);
3013 return 0;
3014 }
3015
3016 static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
3017 {
3018 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
3019 struct btrfs_trans_handle *trans;
3020 u64 transid;
3021 int ret;
3022
3023 trans = btrfs_start_transaction(root, 0);
3024 if (IS_ERR(trans))
3025 return PTR_ERR(trans);
3026 transid = trans->transid;
3027 ret = btrfs_commit_transaction_async(trans, root, 0);
3028 if (ret) {
3029 btrfs_end_transaction(trans, root);
3030 return ret;
3031 }
3032
3033 if (argp)
3034 if (copy_to_user(argp, &transid, sizeof(transid)))
3035 return -EFAULT;
3036 return 0;
3037 }
3038
3039 static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
3040 {
3041 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
3042 u64 transid;
3043
3044 if (argp) {
3045 if (copy_from_user(&transid, argp, sizeof(transid)))
3046 return -EFAULT;
3047 } else {
3048 transid = 0; /* current trans */
3049 }
3050 return btrfs_wait_for_commit(root, transid);
3051 }
3052
3053 static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg)
3054 {
3055 int ret;
3056 struct btrfs_ioctl_scrub_args *sa;
3057
3058 if (!capable(CAP_SYS_ADMIN))
3059 return -EPERM;
3060
3061 sa = memdup_user(arg, sizeof(*sa));
3062 if (IS_ERR(sa))
3063 return PTR_ERR(sa);
3064
3065 ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end,
3066 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY);
3067
3068 if (copy_to_user(arg, sa, sizeof(*sa)))
3069 ret = -EFAULT;
3070
3071 kfree(sa);
3072 return ret;
3073 }
3074
3075 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
3076 {
3077 if (!capable(CAP_SYS_ADMIN))
3078 return -EPERM;
3079
3080 return btrfs_scrub_cancel(root);
3081 }
3082
3083 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
3084 void __user *arg)
3085 {
3086 struct btrfs_ioctl_scrub_args *sa;
3087 int ret;
3088
3089 if (!capable(CAP_SYS_ADMIN))
3090 return -EPERM;
3091
3092 sa = memdup_user(arg, sizeof(*sa));
3093 if (IS_ERR(sa))
3094 return PTR_ERR(sa);
3095
3096 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
3097
3098 if (copy_to_user(arg, sa, sizeof(*sa)))
3099 ret = -EFAULT;
3100
3101 kfree(sa);
3102 return ret;
3103 }
3104
3105 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
3106 void __user *arg)
3107 {
3108 struct btrfs_ioctl_get_dev_stats *sa;
3109 int ret;
3110
3111 sa = memdup_user(arg, sizeof(*sa));
3112 if (IS_ERR(sa))
3113 return PTR_ERR(sa);
3114
3115 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3116 kfree(sa);
3117 return -EPERM;
3118 }
3119
3120 ret = btrfs_get_dev_stats(root, sa);
3121
3122 if (copy_to_user(arg, sa, sizeof(*sa)))
3123 ret = -EFAULT;
3124
3125 kfree(sa);
3126 return ret;
3127 }
3128
3129 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3130 {
3131 int ret = 0;
3132 int i;
3133 u64 rel_ptr;
3134 int size;
3135 struct btrfs_ioctl_ino_path_args *ipa = NULL;
3136 struct inode_fs_paths *ipath = NULL;
3137 struct btrfs_path *path;
3138
3139 if (!capable(CAP_SYS_ADMIN))
3140 return -EPERM;
3141
3142 path = btrfs_alloc_path();
3143 if (!path) {
3144 ret = -ENOMEM;
3145 goto out;
3146 }
3147
3148 ipa = memdup_user(arg, sizeof(*ipa));
3149 if (IS_ERR(ipa)) {
3150 ret = PTR_ERR(ipa);
3151 ipa = NULL;
3152 goto out;
3153 }
3154
3155 size = min_t(u32, ipa->size, 4096);
3156 ipath = init_ipath(size, root, path);
3157 if (IS_ERR(ipath)) {
3158 ret = PTR_ERR(ipath);
3159 ipath = NULL;
3160 goto out;
3161 }
3162
3163 ret = paths_from_inode(ipa->inum, ipath);
3164 if (ret < 0)
3165 goto out;
3166
3167 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3168 rel_ptr = ipath->fspath->val[i] -
3169 (u64)(unsigned long)ipath->fspath->val;
3170 ipath->fspath->val[i] = rel_ptr;
3171 }
3172
3173 ret = copy_to_user((void *)(unsigned long)ipa->fspath,
3174 (void *)(unsigned long)ipath->fspath, size);
3175 if (ret) {
3176 ret = -EFAULT;
3177 goto out;
3178 }
3179
3180 out:
3181 btrfs_free_path(path);
3182 free_ipath(ipath);
3183 kfree(ipa);
3184
3185 return ret;
3186 }
3187
3188 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3189 {
3190 struct btrfs_data_container *inodes = ctx;
3191 const size_t c = 3 * sizeof(u64);
3192
3193 if (inodes->bytes_left >= c) {
3194 inodes->bytes_left -= c;
3195 inodes->val[inodes->elem_cnt] = inum;
3196 inodes->val[inodes->elem_cnt + 1] = offset;
3197 inodes->val[inodes->elem_cnt + 2] = root;
3198 inodes->elem_cnt += 3;
3199 } else {
3200 inodes->bytes_missing += c - inodes->bytes_left;
3201 inodes->bytes_left = 0;
3202 inodes->elem_missed += 3;
3203 }
3204
3205 return 0;
3206 }
3207
3208 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
3209 void __user *arg)
3210 {
3211 int ret = 0;
3212 int size;
3213 u64 extent_item_pos;
3214 struct btrfs_ioctl_logical_ino_args *loi;
3215 struct btrfs_data_container *inodes = NULL;
3216 struct btrfs_path *path = NULL;
3217 struct btrfs_key key;
3218
3219 if (!capable(CAP_SYS_ADMIN))
3220 return -EPERM;
3221
3222 loi = memdup_user(arg, sizeof(*loi));
3223 if (IS_ERR(loi)) {
3224 ret = PTR_ERR(loi);
3225 loi = NULL;
3226 goto out;
3227 }
3228
3229 path = btrfs_alloc_path();
3230 if (!path) {
3231 ret = -ENOMEM;
3232 goto out;
3233 }
3234
3235 size = min_t(u32, loi->size, 4096);
3236 inodes = init_data_container(size);
3237 if (IS_ERR(inodes)) {
3238 ret = PTR_ERR(inodes);
3239 inodes = NULL;
3240 goto out;
3241 }
3242
3243 ret = extent_from_logical(root->fs_info, loi->logical, path, &key);
3244 btrfs_release_path(path);
3245
3246 if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK)
3247 ret = -ENOENT;
3248 if (ret < 0)
3249 goto out;
3250
3251 extent_item_pos = loi->logical - key.objectid;
3252 ret = iterate_extent_inodes(root->fs_info, key.objectid,
3253 extent_item_pos, 0, build_ino_list,
3254 inodes);
3255
3256 if (ret < 0)
3257 goto out;
3258
3259 ret = copy_to_user((void *)(unsigned long)loi->inodes,
3260 (void *)(unsigned long)inodes, size);
3261 if (ret)
3262 ret = -EFAULT;
3263
3264 out:
3265 btrfs_free_path(path);
3266 kfree(inodes);
3267 kfree(loi);
3268
3269 return ret;
3270 }
3271
3272 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
3273 struct btrfs_ioctl_balance_args *bargs)
3274 {
3275 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3276
3277 bargs->flags = bctl->flags;
3278
3279 if (atomic_read(&fs_info->balance_running))
3280 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3281 if (atomic_read(&fs_info->balance_pause_req))
3282 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3283 if (atomic_read(&fs_info->balance_cancel_req))
3284 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3285
3286 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3287 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3288 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3289
3290 if (lock) {
3291 spin_lock(&fs_info->balance_lock);
3292 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3293 spin_unlock(&fs_info->balance_lock);
3294 } else {
3295 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3296 }
3297 }
3298
3299 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
3300 {
3301 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3302 struct btrfs_fs_info *fs_info = root->fs_info;
3303 struct btrfs_ioctl_balance_args *bargs;
3304 struct btrfs_balance_control *bctl;
3305 int ret;
3306
3307 if (!capable(CAP_SYS_ADMIN))
3308 return -EPERM;
3309
3310 ret = mnt_want_write_file(file);
3311 if (ret)
3312 return ret;
3313
3314 mutex_lock(&fs_info->volume_mutex);
3315 mutex_lock(&fs_info->balance_mutex);
3316
3317 if (arg) {
3318 bargs = memdup_user(arg, sizeof(*bargs));
3319 if (IS_ERR(bargs)) {
3320 ret = PTR_ERR(bargs);
3321 goto out;
3322 }
3323
3324 if (bargs->flags & BTRFS_BALANCE_RESUME) {
3325 if (!fs_info->balance_ctl) {
3326 ret = -ENOTCONN;
3327 goto out_bargs;
3328 }
3329
3330 bctl = fs_info->balance_ctl;
3331 spin_lock(&fs_info->balance_lock);
3332 bctl->flags |= BTRFS_BALANCE_RESUME;
3333 spin_unlock(&fs_info->balance_lock);
3334
3335 goto do_balance;
3336 }
3337 } else {
3338 bargs = NULL;
3339 }
3340
3341 if (fs_info->balance_ctl) {
3342 ret = -EINPROGRESS;
3343 goto out_bargs;
3344 }
3345
3346 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3347 if (!bctl) {
3348 ret = -ENOMEM;
3349 goto out_bargs;
3350 }
3351
3352 bctl->fs_info = fs_info;
3353 if (arg) {
3354 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
3355 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
3356 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
3357
3358 bctl->flags = bargs->flags;
3359 } else {
3360 /* balance everything - no filters */
3361 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
3362 }
3363
3364 do_balance:
3365 ret = btrfs_balance(bctl, bargs);
3366 /*
3367 * bctl is freed in __cancel_balance or in free_fs_info if
3368 * restriper was paused all the way until unmount
3369 */
3370 if (arg) {
3371 if (copy_to_user(arg, bargs, sizeof(*bargs)))
3372 ret = -EFAULT;
3373 }
3374
3375 out_bargs:
3376 kfree(bargs);
3377 out:
3378 mutex_unlock(&fs_info->balance_mutex);
3379 mutex_unlock(&fs_info->volume_mutex);
3380 mnt_drop_write_file(file);
3381 return ret;
3382 }
3383
3384 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
3385 {
3386 if (!capable(CAP_SYS_ADMIN))
3387 return -EPERM;
3388
3389 switch (cmd) {
3390 case BTRFS_BALANCE_CTL_PAUSE:
3391 return btrfs_pause_balance(root->fs_info);
3392 case BTRFS_BALANCE_CTL_CANCEL:
3393 return btrfs_cancel_balance(root->fs_info);
3394 }
3395
3396 return -EINVAL;
3397 }
3398
3399 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
3400 void __user *arg)
3401 {
3402 struct btrfs_fs_info *fs_info = root->fs_info;
3403 struct btrfs_ioctl_balance_args *bargs;
3404 int ret = 0;
3405
3406 if (!capable(CAP_SYS_ADMIN))
3407 return -EPERM;
3408
3409 mutex_lock(&fs_info->balance_mutex);
3410 if (!fs_info->balance_ctl) {
3411 ret = -ENOTCONN;
3412 goto out;
3413 }
3414
3415 bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
3416 if (!bargs) {
3417 ret = -ENOMEM;
3418 goto out;
3419 }
3420
3421 update_ioctl_balance_args(fs_info, 1, bargs);
3422
3423 if (copy_to_user(arg, bargs, sizeof(*bargs)))
3424 ret = -EFAULT;
3425
3426 kfree(bargs);
3427 out:
3428 mutex_unlock(&fs_info->balance_mutex);
3429 return ret;
3430 }
3431
3432 static long btrfs_ioctl_quota_ctl(struct btrfs_root *root, void __user *arg)
3433 {
3434 struct btrfs_ioctl_quota_ctl_args *sa;
3435 struct btrfs_trans_handle *trans = NULL;
3436 int ret;
3437 int err;
3438
3439 if (!capable(CAP_SYS_ADMIN))
3440 return -EPERM;
3441
3442 if (root->fs_info->sb->s_flags & MS_RDONLY)
3443 return -EROFS;
3444
3445 sa = memdup_user(arg, sizeof(*sa));
3446 if (IS_ERR(sa))
3447 return PTR_ERR(sa);
3448
3449 if (sa->cmd != BTRFS_QUOTA_CTL_RESCAN) {
3450 trans = btrfs_start_transaction(root, 2);
3451 if (IS_ERR(trans)) {
3452 ret = PTR_ERR(trans);
3453 goto out;
3454 }
3455 }
3456
3457 switch (sa->cmd) {
3458 case BTRFS_QUOTA_CTL_ENABLE:
3459 ret = btrfs_quota_enable(trans, root->fs_info);
3460 break;
3461 case BTRFS_QUOTA_CTL_DISABLE:
3462 ret = btrfs_quota_disable(trans, root->fs_info);
3463 break;
3464 case BTRFS_QUOTA_CTL_RESCAN:
3465 ret = btrfs_quota_rescan(root->fs_info);
3466 break;
3467 default:
3468 ret = -EINVAL;
3469 break;
3470 }
3471
3472 if (copy_to_user(arg, sa, sizeof(*sa)))
3473 ret = -EFAULT;
3474
3475 if (trans) {
3476 err = btrfs_commit_transaction(trans, root);
3477 if (err && !ret)
3478 ret = err;
3479 }
3480
3481 out:
3482 kfree(sa);
3483 return ret;
3484 }
3485
3486 static long btrfs_ioctl_qgroup_assign(struct btrfs_root *root, void __user *arg)
3487 {
3488 struct btrfs_ioctl_qgroup_assign_args *sa;
3489 struct btrfs_trans_handle *trans;
3490 int ret;
3491 int err;
3492
3493 if (!capable(CAP_SYS_ADMIN))
3494 return -EPERM;
3495
3496 if (root->fs_info->sb->s_flags & MS_RDONLY)
3497 return -EROFS;
3498
3499 sa = memdup_user(arg, sizeof(*sa));
3500 if (IS_ERR(sa))
3501 return PTR_ERR(sa);
3502
3503 trans = btrfs_join_transaction(root);
3504 if (IS_ERR(trans)) {
3505 ret = PTR_ERR(trans);
3506 goto out;
3507 }
3508
3509 /* FIXME: check if the IDs really exist */
3510 if (sa->assign) {
3511 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
3512 sa->src, sa->dst);
3513 } else {
3514 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
3515 sa->src, sa->dst);
3516 }
3517
3518 err = btrfs_end_transaction(trans, root);
3519 if (err && !ret)
3520 ret = err;
3521
3522 out:
3523 kfree(sa);
3524 return ret;
3525 }
3526
3527 static long btrfs_ioctl_qgroup_create(struct btrfs_root *root, void __user *arg)
3528 {
3529 struct btrfs_ioctl_qgroup_create_args *sa;
3530 struct btrfs_trans_handle *trans;
3531 int ret;
3532 int err;
3533
3534 if (!capable(CAP_SYS_ADMIN))
3535 return -EPERM;
3536
3537 if (root->fs_info->sb->s_flags & MS_RDONLY)
3538 return -EROFS;
3539
3540 sa = memdup_user(arg, sizeof(*sa));
3541 if (IS_ERR(sa))
3542 return PTR_ERR(sa);
3543
3544 trans = btrfs_join_transaction(root);
3545 if (IS_ERR(trans)) {
3546 ret = PTR_ERR(trans);
3547 goto out;
3548 }
3549
3550 /* FIXME: check if the IDs really exist */
3551 if (sa->create) {
3552 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
3553 NULL);
3554 } else {
3555 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
3556 }
3557
3558 err = btrfs_end_transaction(trans, root);
3559 if (err && !ret)
3560 ret = err;
3561
3562 out:
3563 kfree(sa);
3564 return ret;
3565 }
3566
3567 static long btrfs_ioctl_qgroup_limit(struct btrfs_root *root, void __user *arg)
3568 {
3569 struct btrfs_ioctl_qgroup_limit_args *sa;
3570 struct btrfs_trans_handle *trans;
3571 int ret;
3572 int err;
3573 u64 qgroupid;
3574
3575 if (!capable(CAP_SYS_ADMIN))
3576 return -EPERM;
3577
3578 if (root->fs_info->sb->s_flags & MS_RDONLY)
3579 return -EROFS;
3580
3581 sa = memdup_user(arg, sizeof(*sa));
3582 if (IS_ERR(sa))
3583 return PTR_ERR(sa);
3584
3585 trans = btrfs_join_transaction(root);
3586 if (IS_ERR(trans)) {
3587 ret = PTR_ERR(trans);
3588 goto out;
3589 }
3590
3591 qgroupid = sa->qgroupid;
3592 if (!qgroupid) {
3593 /* take the current subvol as qgroup */
3594 qgroupid = root->root_key.objectid;
3595 }
3596
3597 /* FIXME: check if the IDs really exist */
3598 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
3599
3600 err = btrfs_end_transaction(trans, root);
3601 if (err && !ret)
3602 ret = err;
3603
3604 out:
3605 kfree(sa);
3606 return ret;
3607 }
3608
3609 static long btrfs_ioctl_set_received_subvol(struct file *file,
3610 void __user *arg)
3611 {
3612 struct btrfs_ioctl_received_subvol_args *sa = NULL;
3613 struct inode *inode = fdentry(file)->d_inode;
3614 struct btrfs_root *root = BTRFS_I(inode)->root;
3615 struct btrfs_root_item *root_item = &root->root_item;
3616 struct btrfs_trans_handle *trans;
3617 struct timespec ct = CURRENT_TIME;
3618 int ret = 0;
3619
3620 ret = mnt_want_write_file(file);
3621 if (ret < 0)
3622 return ret;
3623
3624 down_write(&root->fs_info->subvol_sem);
3625
3626 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
3627 ret = -EINVAL;
3628 goto out;
3629 }
3630
3631 if (btrfs_root_readonly(root)) {
3632 ret = -EROFS;
3633 goto out;
3634 }
3635
3636 if (!inode_owner_or_capable(inode)) {
3637 ret = -EACCES;
3638 goto out;
3639 }
3640
3641 sa = memdup_user(arg, sizeof(*sa));
3642 if (IS_ERR(sa)) {
3643 ret = PTR_ERR(sa);
3644 sa = NULL;
3645 goto out;
3646 }
3647
3648 trans = btrfs_start_transaction(root, 1);
3649 if (IS_ERR(trans)) {
3650 ret = PTR_ERR(trans);
3651 trans = NULL;
3652 goto out;
3653 }
3654
3655 sa->rtransid = trans->transid;
3656 sa->rtime.sec = ct.tv_sec;
3657 sa->rtime.nsec = ct.tv_nsec;
3658
3659 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
3660 btrfs_set_root_stransid(root_item, sa->stransid);
3661 btrfs_set_root_rtransid(root_item, sa->rtransid);
3662 root_item->stime.sec = cpu_to_le64(sa->stime.sec);
3663 root_item->stime.nsec = cpu_to_le32(sa->stime.nsec);
3664 root_item->rtime.sec = cpu_to_le64(sa->rtime.sec);
3665 root_item->rtime.nsec = cpu_to_le32(sa->rtime.nsec);
3666
3667 ret = btrfs_update_root(trans, root->fs_info->tree_root,
3668 &root->root_key, &root->root_item);
3669 if (ret < 0) {
3670 btrfs_end_transaction(trans, root);
3671 trans = NULL;
3672 goto out;
3673 } else {
3674 ret = btrfs_commit_transaction(trans, root);
3675 if (ret < 0)
3676 goto out;
3677 }
3678
3679 ret = copy_to_user(arg, sa, sizeof(*sa));
3680 if (ret)
3681 ret = -EFAULT;
3682
3683 out:
3684 kfree(sa);
3685 up_write(&root->fs_info->subvol_sem);
3686 mnt_drop_write_file(file);
3687 return ret;
3688 }
3689
3690 long btrfs_ioctl(struct file *file, unsigned int
3691 cmd, unsigned long arg)
3692 {
3693 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3694 void __user *argp = (void __user *)arg;
3695
3696 switch (cmd) {
3697 case FS_IOC_GETFLAGS:
3698 return btrfs_ioctl_getflags(file, argp);
3699 case FS_IOC_SETFLAGS:
3700 return btrfs_ioctl_setflags(file, argp);
3701 case FS_IOC_GETVERSION:
3702 return btrfs_ioctl_getversion(file, argp);
3703 case FITRIM:
3704 return btrfs_ioctl_fitrim(file, argp);
3705 case BTRFS_IOC_SNAP_CREATE:
3706 return btrfs_ioctl_snap_create(file, argp, 0);
3707 case BTRFS_IOC_SNAP_CREATE_V2:
3708 return btrfs_ioctl_snap_create_v2(file, argp, 0);
3709 case BTRFS_IOC_SUBVOL_CREATE:
3710 return btrfs_ioctl_snap_create(file, argp, 1);
3711 case BTRFS_IOC_SUBVOL_CREATE_V2:
3712 return btrfs_ioctl_snap_create_v2(file, argp, 1);
3713 case BTRFS_IOC_SNAP_DESTROY:
3714 return btrfs_ioctl_snap_destroy(file, argp);
3715 case BTRFS_IOC_SUBVOL_GETFLAGS:
3716 return btrfs_ioctl_subvol_getflags(file, argp);
3717 case BTRFS_IOC_SUBVOL_SETFLAGS:
3718 return btrfs_ioctl_subvol_setflags(file, argp);
3719 case BTRFS_IOC_DEFAULT_SUBVOL:
3720 return btrfs_ioctl_default_subvol(file, argp);
3721 case BTRFS_IOC_DEFRAG:
3722 return btrfs_ioctl_defrag(file, NULL);
3723 case BTRFS_IOC_DEFRAG_RANGE:
3724 return btrfs_ioctl_defrag(file, argp);
3725 case BTRFS_IOC_RESIZE:
3726 return btrfs_ioctl_resize(root, argp);
3727 case BTRFS_IOC_ADD_DEV:
3728 return btrfs_ioctl_add_dev(root, argp);
3729 case BTRFS_IOC_RM_DEV:
3730 return btrfs_ioctl_rm_dev(root, argp);
3731 case BTRFS_IOC_FS_INFO:
3732 return btrfs_ioctl_fs_info(root, argp);
3733 case BTRFS_IOC_DEV_INFO:
3734 return btrfs_ioctl_dev_info(root, argp);
3735 case BTRFS_IOC_BALANCE:
3736 return btrfs_ioctl_balance(file, NULL);
3737 case BTRFS_IOC_CLONE:
3738 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
3739 case BTRFS_IOC_CLONE_RANGE:
3740 return btrfs_ioctl_clone_range(file, argp);
3741 case BTRFS_IOC_TRANS_START:
3742 return btrfs_ioctl_trans_start(file);
3743 case BTRFS_IOC_TRANS_END:
3744 return btrfs_ioctl_trans_end(file);
3745 case BTRFS_IOC_TREE_SEARCH:
3746 return btrfs_ioctl_tree_search(file, argp);
3747 case BTRFS_IOC_INO_LOOKUP:
3748 return btrfs_ioctl_ino_lookup(file, argp);
3749 case BTRFS_IOC_INO_PATHS:
3750 return btrfs_ioctl_ino_to_path(root, argp);
3751 case BTRFS_IOC_LOGICAL_INO:
3752 return btrfs_ioctl_logical_to_ino(root, argp);
3753 case BTRFS_IOC_SPACE_INFO:
3754 return btrfs_ioctl_space_info(root, argp);
3755 case BTRFS_IOC_SYNC:
3756 btrfs_sync_fs(file->f_dentry->d_sb, 1);
3757 return 0;
3758 case BTRFS_IOC_START_SYNC:
3759 return btrfs_ioctl_start_sync(file, argp);
3760 case BTRFS_IOC_WAIT_SYNC:
3761 return btrfs_ioctl_wait_sync(file, argp);
3762 case BTRFS_IOC_SCRUB:
3763 return btrfs_ioctl_scrub(root, argp);
3764 case BTRFS_IOC_SCRUB_CANCEL:
3765 return btrfs_ioctl_scrub_cancel(root, argp);
3766 case BTRFS_IOC_SCRUB_PROGRESS:
3767 return btrfs_ioctl_scrub_progress(root, argp);
3768 case BTRFS_IOC_BALANCE_V2:
3769 return btrfs_ioctl_balance(file, argp);
3770 case BTRFS_IOC_BALANCE_CTL:
3771 return btrfs_ioctl_balance_ctl(root, arg);
3772 case BTRFS_IOC_BALANCE_PROGRESS:
3773 return btrfs_ioctl_balance_progress(root, argp);
3774 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
3775 return btrfs_ioctl_set_received_subvol(file, argp);
3776 case BTRFS_IOC_SEND:
3777 return btrfs_ioctl_send(file, argp);
3778 case BTRFS_IOC_GET_DEV_STATS:
3779 return btrfs_ioctl_get_dev_stats(root, argp);
3780 case BTRFS_IOC_QUOTA_CTL:
3781 return btrfs_ioctl_quota_ctl(root, argp);
3782 case BTRFS_IOC_QGROUP_ASSIGN:
3783 return btrfs_ioctl_qgroup_assign(root, argp);
3784 case BTRFS_IOC_QGROUP_CREATE:
3785 return btrfs_ioctl_qgroup_create(root, argp);
3786 case BTRFS_IOC_QGROUP_LIMIT:
3787 return btrfs_ioctl_qgroup_limit(root, argp);
3788 }
3789
3790 return -ENOTTY;
3791 }
Linus' kernel tree