?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Btrfs: make sure not to defrag extents past i_size
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / btrfs / ioctl.c
blobefc4e4a85a6988b69bdf7094feacfb00a6ebac11
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19 #include <linux/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.h>
23 #include <linux/fs.h>
24 #include <linux/fsnotify.h>
25 #include <linux/pagemap.h>
26 #include <linux/highmem.h>
27 #include <linux/time.h>
28 #include <linux/init.h>
29 #include <linux/string.h>
30 #include <linux/backing-dev.h>
31 #include <linux/mount.h>
32 #include <linux/mpage.h>
33 #include <linux/namei.h>
34 #include <linux/swap.h>
35 #include <linux/writeback.h>
36 #include <linux/statfs.h>
37 #include <linux/compat.h>
38 #include <linux/bit_spinlock.h>
39 #include <linux/security.h>
40 #include <linux/xattr.h>
41 #include <linux/vmalloc.h>
42 #include <linux/slab.h>
43 #include <linux/blkdev.h>
44 #include "compat.h"
45 #include "ctree.h"
46 #include "disk-io.h"
47 #include "transaction.h"
48 #include "btrfs_inode.h"
49 #include "ioctl.h"
50 #include "print-tree.h"
51 #include "volumes.h"
52 #include "locking.h"
53 #include "inode-map.h"
54
55 /* Mask out flags that are inappropriate for the given type of inode. */
56 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
57 {
58 if (S_ISDIR(mode))
59 return flags;
60 else if (S_ISREG(mode))
61 return flags & ~FS_DIRSYNC_FL;
62 else
63 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
64 }
65
66 /*
67 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
68 */
69 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
70 {
71 unsigned int iflags = 0;
72
73 if (flags & BTRFS_INODE_SYNC)
74 iflags |= FS_SYNC_FL;
75 if (flags & BTRFS_INODE_IMMUTABLE)
76 iflags |= FS_IMMUTABLE_FL;
77 if (flags & BTRFS_INODE_APPEND)
78 iflags |= FS_APPEND_FL;
79 if (flags & BTRFS_INODE_NODUMP)
80 iflags |= FS_NODUMP_FL;
81 if (flags & BTRFS_INODE_NOATIME)
82 iflags |= FS_NOATIME_FL;
83 if (flags & BTRFS_INODE_DIRSYNC)
84 iflags |= FS_DIRSYNC_FL;
85 if (flags & BTRFS_INODE_NODATACOW)
86 iflags |= FS_NOCOW_FL;
87
88 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
89 iflags |= FS_COMPR_FL;
90 else if (flags & BTRFS_INODE_NOCOMPRESS)
91 iflags |= FS_NOCOMP_FL;
92
93 return iflags;
94 }
95
96 /*
97 * Update inode->i_flags based on the btrfs internal flags.
98 */
99 void btrfs_update_iflags(struct inode *inode)
100 {
101 struct btrfs_inode *ip = BTRFS_I(inode);
102
103 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
104
105 if (ip->flags & BTRFS_INODE_SYNC)
106 inode->i_flags |= S_SYNC;
107 if (ip->flags & BTRFS_INODE_IMMUTABLE)
108 inode->i_flags |= S_IMMUTABLE;
109 if (ip->flags & BTRFS_INODE_APPEND)
110 inode->i_flags |= S_APPEND;
111 if (ip->flags & BTRFS_INODE_NOATIME)
112 inode->i_flags |= S_NOATIME;
113 if (ip->flags & BTRFS_INODE_DIRSYNC)
114 inode->i_flags |= S_DIRSYNC;
115 }
116
117 /*
118 * Inherit flags from the parent inode.
119 *
120 * Unlike extN we don't have any flags we don't want to inherit currently.
121 */
122 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
123 {
124 unsigned int flags;
125
126 if (!dir)
127 return;
128
129 flags = BTRFS_I(dir)->flags;
130
131 if (S_ISREG(inode->i_mode))
132 flags &= ~BTRFS_INODE_DIRSYNC;
133 else if (!S_ISDIR(inode->i_mode))
134 flags &= (BTRFS_INODE_NODUMP | BTRFS_INODE_NOATIME);
135
136 BTRFS_I(inode)->flags = flags;
137 btrfs_update_iflags(inode);
138 }
139
140 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
141 {
142 struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
143 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
144
145 if (copy_to_user(arg, &flags, sizeof(flags)))
146 return -EFAULT;
147 return 0;
148 }
149
150 static int check_flags(unsigned int flags)
151 {
152 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
153 FS_NOATIME_FL | FS_NODUMP_FL | \
154 FS_SYNC_FL | FS_DIRSYNC_FL | \
155 FS_NOCOMP_FL | FS_COMPR_FL |
156 FS_NOCOW_FL))
157 return -EOPNOTSUPP;
158
159 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
160 return -EINVAL;
161
162 return 0;
163 }
164
165 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
166 {
167 struct inode *inode = file->f_path.dentry->d_inode;
168 struct btrfs_inode *ip = BTRFS_I(inode);
169 struct btrfs_root *root = ip->root;
170 struct btrfs_trans_handle *trans;
171 unsigned int flags, oldflags;
172 int ret;
173
174 if (btrfs_root_readonly(root))
175 return -EROFS;
176
177 if (copy_from_user(&flags, arg, sizeof(flags)))
178 return -EFAULT;
179
180 ret = check_flags(flags);
181 if (ret)
182 return ret;
183
184 if (!inode_owner_or_capable(inode))
185 return -EACCES;
186
187 mutex_lock(&inode->i_mutex);
188
189 flags = btrfs_mask_flags(inode->i_mode, flags);
190 oldflags = btrfs_flags_to_ioctl(ip->flags);
191 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
192 if (!capable(CAP_LINUX_IMMUTABLE)) {
193 ret = -EPERM;
194 goto out_unlock;
195 }
196 }
197
198 ret = mnt_want_write(file->f_path.mnt);
199 if (ret)
200 goto out_unlock;
201
202 if (flags & FS_SYNC_FL)
203 ip->flags |= BTRFS_INODE_SYNC;
204 else
205 ip->flags &= ~BTRFS_INODE_SYNC;
206 if (flags & FS_IMMUTABLE_FL)
207 ip->flags |= BTRFS_INODE_IMMUTABLE;
208 else
209 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
210 if (flags & FS_APPEND_FL)
211 ip->flags |= BTRFS_INODE_APPEND;
212 else
213 ip->flags &= ~BTRFS_INODE_APPEND;
214 if (flags & FS_NODUMP_FL)
215 ip->flags |= BTRFS_INODE_NODUMP;
216 else
217 ip->flags &= ~BTRFS_INODE_NODUMP;
218 if (flags & FS_NOATIME_FL)
219 ip->flags |= BTRFS_INODE_NOATIME;
220 else
221 ip->flags &= ~BTRFS_INODE_NOATIME;
222 if (flags & FS_DIRSYNC_FL)
223 ip->flags |= BTRFS_INODE_DIRSYNC;
224 else
225 ip->flags &= ~BTRFS_INODE_DIRSYNC;
226 if (flags & FS_NOCOW_FL)
227 ip->flags |= BTRFS_INODE_NODATACOW;
228 else
229 ip->flags &= ~BTRFS_INODE_NODATACOW;
230
231 /*
232 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
233 * flag may be changed automatically if compression code won't make
234 * things smaller.
235 */
236 if (flags & FS_NOCOMP_FL) {
237 ip->flags &= ~BTRFS_INODE_COMPRESS;
238 ip->flags |= BTRFS_INODE_NOCOMPRESS;
239 } else if (flags & FS_COMPR_FL) {
240 ip->flags |= BTRFS_INODE_COMPRESS;
241 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
242 } else {
243 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
244 }
245
246 trans = btrfs_join_transaction(root);
247 BUG_ON(IS_ERR(trans));
248
249 ret = btrfs_update_inode(trans, root, inode);
250 BUG_ON(ret);
251
252 btrfs_update_iflags(inode);
253 inode->i_ctime = CURRENT_TIME;
254 btrfs_end_transaction(trans, root);
255
256 mnt_drop_write(file->f_path.mnt);
257
258 ret = 0;
259 out_unlock:
260 mutex_unlock(&inode->i_mutex);
261 return ret;
262 }
263
264 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
265 {
266 struct inode *inode = file->f_path.dentry->d_inode;
267
268 return put_user(inode->i_generation, arg);
269 }
270
271 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
272 {
273 struct btrfs_root *root = fdentry(file)->d_sb->s_fs_info;
274 struct btrfs_fs_info *fs_info = root->fs_info;
275 struct btrfs_device *device;
276 struct request_queue *q;
277 struct fstrim_range range;
278 u64 minlen = ULLONG_MAX;
279 u64 num_devices = 0;
280 int ret;
281
282 if (!capable(CAP_SYS_ADMIN))
283 return -EPERM;
284
285 rcu_read_lock();
286 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
287 dev_list) {
288 if (!device->bdev)
289 continue;
290 q = bdev_get_queue(device->bdev);
291 if (blk_queue_discard(q)) {
292 num_devices++;
293 minlen = min((u64)q->limits.discard_granularity,
294 minlen);
295 }
296 }
297 rcu_read_unlock();
298 if (!num_devices)
299 return -EOPNOTSUPP;
300
301 if (copy_from_user(&range, arg, sizeof(range)))
302 return -EFAULT;
303
304 range.minlen = max(range.minlen, minlen);
305 ret = btrfs_trim_fs(root, &range);
306 if (ret < 0)
307 return ret;
308
309 if (copy_to_user(arg, &range, sizeof(range)))
310 return -EFAULT;
311
312 return 0;
313 }
314
315 static noinline int create_subvol(struct btrfs_root *root,
316 struct dentry *dentry,
317 char *name, int namelen,
318 u64 *async_transid)
319 {
320 struct btrfs_trans_handle *trans;
321 struct btrfs_key key;
322 struct btrfs_root_item root_item;
323 struct btrfs_inode_item *inode_item;
324 struct extent_buffer *leaf;
325 struct btrfs_root *new_root;
326 struct dentry *parent = dget_parent(dentry);
327 struct inode *dir;
328 int ret;
329 int err;
330 u64 objectid;
331 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
332 u64 index = 0;
333
334 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
335 if (ret) {
336 dput(parent);
337 return ret;
338 }
339
340 dir = parent->d_inode;
341
342 /*
343 * 1 - inode item
344 * 2 - refs
345 * 1 - root item
346 * 2 - dir items
347 */
348 trans = btrfs_start_transaction(root, 6);
349 if (IS_ERR(trans)) {
350 dput(parent);
351 return PTR_ERR(trans);
352 }
353
354 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
355 0, objectid, NULL, 0, 0, 0);
356 if (IS_ERR(leaf)) {
357 ret = PTR_ERR(leaf);
358 goto fail;
359 }
360
361 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
362 btrfs_set_header_bytenr(leaf, leaf->start);
363 btrfs_set_header_generation(leaf, trans->transid);
364 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
365 btrfs_set_header_owner(leaf, objectid);
366
367 write_extent_buffer(leaf, root->fs_info->fsid,
368 (unsigned long)btrfs_header_fsid(leaf),
369 BTRFS_FSID_SIZE);
370 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
371 (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
372 BTRFS_UUID_SIZE);
373 btrfs_mark_buffer_dirty(leaf);
374
375 inode_item = &root_item.inode;
376 memset(inode_item, 0, sizeof(*inode_item));
377 inode_item->generation = cpu_to_le64(1);
378 inode_item->size = cpu_to_le64(3);
379 inode_item->nlink = cpu_to_le32(1);
380 inode_item->nbytes = cpu_to_le64(root->leafsize);
381 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
382
383 root_item.flags = 0;
384 root_item.byte_limit = 0;
385 inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
386
387 btrfs_set_root_bytenr(&root_item, leaf->start);
388 btrfs_set_root_generation(&root_item, trans->transid);
389 btrfs_set_root_level(&root_item, 0);
390 btrfs_set_root_refs(&root_item, 1);
391 btrfs_set_root_used(&root_item, leaf->len);
392 btrfs_set_root_last_snapshot(&root_item, 0);
393
394 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
395 root_item.drop_level = 0;
396
397 btrfs_tree_unlock(leaf);
398 free_extent_buffer(leaf);
399 leaf = NULL;
400
401 btrfs_set_root_dirid(&root_item, new_dirid);
402
403 key.objectid = objectid;
404 key.offset = 0;
405 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
406 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
407 &root_item);
408 if (ret)
409 goto fail;
410
411 key.offset = (u64)-1;
412 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
413 BUG_ON(IS_ERR(new_root));
414
415 btrfs_record_root_in_trans(trans, new_root);
416
417 ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
418 /*
419 * insert the directory item
420 */
421 ret = btrfs_set_inode_index(dir, &index);
422 BUG_ON(ret);
423
424 ret = btrfs_insert_dir_item(trans, root,
425 name, namelen, dir, &key,
426 BTRFS_FT_DIR, index);
427 if (ret)
428 goto fail;
429
430 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
431 ret = btrfs_update_inode(trans, root, dir);
432 BUG_ON(ret);
433
434 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
435 objectid, root->root_key.objectid,
436 btrfs_ino(dir), index, name, namelen);
437
438 BUG_ON(ret);
439
440 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
441 fail:
442 dput(parent);
443 if (async_transid) {
444 *async_transid = trans->transid;
445 err = btrfs_commit_transaction_async(trans, root, 1);
446 } else {
447 err = btrfs_commit_transaction(trans, root);
448 }
449 if (err && !ret)
450 ret = err;
451 return ret;
452 }
453
454 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
455 char *name, int namelen, u64 *async_transid,
456 bool readonly)
457 {
458 struct inode *inode;
459 struct dentry *parent;
460 struct btrfs_pending_snapshot *pending_snapshot;
461 struct btrfs_trans_handle *trans;
462 int ret;
463
464 if (!root->ref_cows)
465 return -EINVAL;
466
467 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
468 if (!pending_snapshot)
469 return -ENOMEM;
470
471 btrfs_init_block_rsv(&pending_snapshot->block_rsv);
472 pending_snapshot->dentry = dentry;
473 pending_snapshot->root = root;
474 pending_snapshot->readonly = readonly;
475
476 trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
477 if (IS_ERR(trans)) {
478 ret = PTR_ERR(trans);
479 goto fail;
480 }
481
482 ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
483 BUG_ON(ret);
484
485 spin_lock(&root->fs_info->trans_lock);
486 list_add(&pending_snapshot->list,
487 &trans->transaction->pending_snapshots);
488 spin_unlock(&root->fs_info->trans_lock);
489 if (async_transid) {
490 *async_transid = trans->transid;
491 ret = btrfs_commit_transaction_async(trans,
492 root->fs_info->extent_root, 1);
493 } else {
494 ret = btrfs_commit_transaction(trans,
495 root->fs_info->extent_root);
496 }
497 BUG_ON(ret);
498
499 ret = pending_snapshot->error;
500 if (ret)
501 goto fail;
502
503 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
504 if (ret)
505 goto fail;
506
507 parent = dget_parent(dentry);
508 inode = btrfs_lookup_dentry(parent->d_inode, dentry);
509 dput(parent);
510 if (IS_ERR(inode)) {
511 ret = PTR_ERR(inode);
512 goto fail;
513 }
514 BUG_ON(!inode);
515 d_instantiate(dentry, inode);
516 ret = 0;
517 fail:
518 kfree(pending_snapshot);
519 return ret;
520 }
521
522 /* copy of check_sticky in fs/namei.c()
523 * It's inline, so penalty for filesystems that don't use sticky bit is
524 * minimal.
525 */
526 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
527 {
528 uid_t fsuid = current_fsuid();
529
530 if (!(dir->i_mode & S_ISVTX))
531 return 0;
532 if (inode->i_uid == fsuid)
533 return 0;
534 if (dir->i_uid == fsuid)
535 return 0;
536 return !capable(CAP_FOWNER);
537 }
538
539 /* copy of may_delete in fs/namei.c()
540 * Check whether we can remove a link victim from directory dir, check
541 * whether the type of victim is right.
542 * 1. We can't do it if dir is read-only (done in permission())
543 * 2. We should have write and exec permissions on dir
544 * 3. We can't remove anything from append-only dir
545 * 4. We can't do anything with immutable dir (done in permission())
546 * 5. If the sticky bit on dir is set we should either
547 * a. be owner of dir, or
548 * b. be owner of victim, or
549 * c. have CAP_FOWNER capability
550 * 6. If the victim is append-only or immutable we can't do antyhing with
551 * links pointing to it.
552 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
553 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
554 * 9. We can't remove a root or mountpoint.
555 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
556 * nfs_async_unlink().
557 */
558
559 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
560 {
561 int error;
562
563 if (!victim->d_inode)
564 return -ENOENT;
565
566 BUG_ON(victim->d_parent->d_inode != dir);
567 audit_inode_child(victim, dir);
568
569 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
570 if (error)
571 return error;
572 if (IS_APPEND(dir))
573 return -EPERM;
574 if (btrfs_check_sticky(dir, victim->d_inode)||
575 IS_APPEND(victim->d_inode)||
576 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
577 return -EPERM;
578 if (isdir) {
579 if (!S_ISDIR(victim->d_inode->i_mode))
580 return -ENOTDIR;
581 if (IS_ROOT(victim))
582 return -EBUSY;
583 } else if (S_ISDIR(victim->d_inode->i_mode))
584 return -EISDIR;
585 if (IS_DEADDIR(dir))
586 return -ENOENT;
587 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
588 return -EBUSY;
589 return 0;
590 }
591
592 /* copy of may_create in fs/namei.c() */
593 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
594 {
595 if (child->d_inode)
596 return -EEXIST;
597 if (IS_DEADDIR(dir))
598 return -ENOENT;
599 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
600 }
601
602 /*
603 * Create a new subvolume below @parent. This is largely modeled after
604 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
605 * inside this filesystem so it's quite a bit simpler.
606 */
607 static noinline int btrfs_mksubvol(struct path *parent,
608 char *name, int namelen,
609 struct btrfs_root *snap_src,
610 u64 *async_transid, bool readonly)
611 {
612 struct inode *dir = parent->dentry->d_inode;
613 struct dentry *dentry;
614 int error;
615
616 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
617
618 dentry = lookup_one_len(name, parent->dentry, namelen);
619 error = PTR_ERR(dentry);
620 if (IS_ERR(dentry))
621 goto out_unlock;
622
623 error = -EEXIST;
624 if (dentry->d_inode)
625 goto out_dput;
626
627 error = mnt_want_write(parent->mnt);
628 if (error)
629 goto out_dput;
630
631 error = btrfs_may_create(dir, dentry);
632 if (error)
633 goto out_drop_write;
634
635 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
636
637 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
638 goto out_up_read;
639
640 if (snap_src) {
641 error = create_snapshot(snap_src, dentry,
642 name, namelen, async_transid, readonly);
643 } else {
644 error = create_subvol(BTRFS_I(dir)->root, dentry,
645 name, namelen, async_transid);
646 }
647 if (!error)
648 fsnotify_mkdir(dir, dentry);
649 out_up_read:
650 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
651 out_drop_write:
652 mnt_drop_write(parent->mnt);
653 out_dput:
654 dput(dentry);
655 out_unlock:
656 mutex_unlock(&dir->i_mutex);
657 return error;
658 }
659
660 /*
661 * When we're defragging a range, we don't want to kick it off again
662 * if it is really just waiting for delalloc to send it down.
663 * If we find a nice big extent or delalloc range for the bytes in the
664 * file you want to defrag, we return 0 to let you know to skip this
665 * part of the file
666 */
667 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
668 {
669 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
670 struct extent_map *em = NULL;
671 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
672 u64 end;
673
674 read_lock(&em_tree->lock);
675 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
676 read_unlock(&em_tree->lock);
677
678 if (em) {
679 end = extent_map_end(em);
680 free_extent_map(em);
681 if (end - offset > thresh)
682 return 0;
683 }
684 /* if we already have a nice delalloc here, just stop */
685 thresh /= 2;
686 end = count_range_bits(io_tree, &offset, offset + thresh,
687 thresh, EXTENT_DELALLOC, 1);
688 if (end >= thresh)
689 return 0;
690 return 1;
691 }
692
693 /*
694 * helper function to walk through a file and find extents
695 * newer than a specific transid, and smaller than thresh.
696 *
697 * This is used by the defragging code to find new and small
698 * extents
699 */
700 static int find_new_extents(struct btrfs_root *root,
701 struct inode *inode, u64 newer_than,
702 u64 *off, int thresh)
703 {
704 struct btrfs_path *path;
705 struct btrfs_key min_key;
706 struct btrfs_key max_key;
707 struct extent_buffer *leaf;
708 struct btrfs_file_extent_item *extent;
709 int type;
710 int ret;
711 u64 ino = btrfs_ino(inode);
712
713 path = btrfs_alloc_path();
714 if (!path)
715 return -ENOMEM;
716
717 min_key.objectid = ino;
718 min_key.type = BTRFS_EXTENT_DATA_KEY;
719 min_key.offset = *off;
720
721 max_key.objectid = ino;
722 max_key.type = (u8)-1;
723 max_key.offset = (u64)-1;
724
725 path->keep_locks = 1;
726
727 while(1) {
728 ret = btrfs_search_forward(root, &min_key, &max_key,
729 path, 0, newer_than);
730 if (ret != 0)
731 goto none;
732 if (min_key.objectid != ino)
733 goto none;
734 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
735 goto none;
736
737 leaf = path->nodes[0];
738 extent = btrfs_item_ptr(leaf, path->slots[0],
739 struct btrfs_file_extent_item);
740
741 type = btrfs_file_extent_type(leaf, extent);
742 if (type == BTRFS_FILE_EXTENT_REG &&
743 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
744 check_defrag_in_cache(inode, min_key.offset, thresh)) {
745 *off = min_key.offset;
746 btrfs_free_path(path);
747 return 0;
748 }
749
750 if (min_key.offset == (u64)-1)
751 goto none;
752
753 min_key.offset++;
754 btrfs_release_path(path);
755 }
756 none:
757 btrfs_free_path(path);
758 return -ENOENT;
759 }
760
761 static int should_defrag_range(struct inode *inode, u64 start, u64 len,
762 int thresh, u64 *last_len, u64 *skip,
763 u64 *defrag_end)
764 {
765 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
766 struct extent_map *em = NULL;
767 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
768 int ret = 1;
769
770 /*
771 * make sure that once we start defragging and extent, we keep on
772 * defragging it
773 */
774 if (start < *defrag_end)
775 return 1;
776
777 *skip = 0;
778
779 /*
780 * hopefully we have this extent in the tree already, try without
781 * the full extent lock
782 */
783 read_lock(&em_tree->lock);
784 em = lookup_extent_mapping(em_tree, start, len);
785 read_unlock(&em_tree->lock);
786
787 if (!em) {
788 /* get the big lock and read metadata off disk */
789 lock_extent(io_tree, start, start + len - 1, GFP_NOFS);
790 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
791 unlock_extent(io_tree, start, start + len - 1, GFP_NOFS);
792
793 if (IS_ERR(em))
794 return 0;
795 }
796
797 /* this will cover holes, and inline extents */
798 if (em->block_start >= EXTENT_MAP_LAST_BYTE)
799 ret = 0;
800
801 /*
802 * we hit a real extent, if it is big don't bother defragging it again
803 */
804 if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
805 ret = 0;
806
807 /*
808 * last_len ends up being a counter of how many bytes we've defragged.
809 * every time we choose not to defrag an extent, we reset *last_len
810 * so that the next tiny extent will force a defrag.
811 *
812 * The end result of this is that tiny extents before a single big
813 * extent will force at least part of that big extent to be defragged.
814 */
815 if (ret) {
816 *last_len += len;
817 *defrag_end = extent_map_end(em);
818 } else {
819 *last_len = 0;
820 *skip = extent_map_end(em);
821 *defrag_end = 0;
822 }
823
824 free_extent_map(em);
825 return ret;
826 }
827
828 /*
829 * it doesn't do much good to defrag one or two pages
830 * at a time. This pulls in a nice chunk of pages
831 * to COW and defrag.
832 *
833 * It also makes sure the delalloc code has enough
834 * dirty data to avoid making new small extents as part
835 * of the defrag
836 *
837 * It's a good idea to start RA on this range
838 * before calling this.
839 */
840 static int cluster_pages_for_defrag(struct inode *inode,
841 struct page **pages,
842 unsigned long start_index,
843 int num_pages)
844 {
845 unsigned long file_end;
846 u64 isize = i_size_read(inode);
847 u64 page_start;
848 u64 page_end;
849 int ret;
850 int i;
851 int i_done;
852 struct btrfs_ordered_extent *ordered;
853 struct extent_state *cached_state = NULL;
854
855 if (isize == 0)
856 return 0;
857 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
858
859 ret = btrfs_delalloc_reserve_space(inode,
860 num_pages << PAGE_CACHE_SHIFT);
861 if (ret)
862 return ret;
863 again:
864 ret = 0;
865 i_done = 0;
866
867 /* step one, lock all the pages */
868 for (i = 0; i < num_pages; i++) {
869 struct page *page;
870 page = find_or_create_page(inode->i_mapping,
871 start_index + i, GFP_NOFS);
872 if (!page)
873 break;
874
875 if (!PageUptodate(page)) {
876 btrfs_readpage(NULL, page);
877 lock_page(page);
878 if (!PageUptodate(page)) {
879 unlock_page(page);
880 page_cache_release(page);
881 ret = -EIO;
882 break;
883 }
884 }
885 isize = i_size_read(inode);
886 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
887 if (!isize || page->index > file_end ||
888 page->mapping != inode->i_mapping) {
889 /* whoops, we blew past eof, skip this page */
890 unlock_page(page);
891 page_cache_release(page);
892 break;
893 }
894 pages[i] = page;
895 i_done++;
896 }
897 if (!i_done || ret)
898 goto out;
899
900 if (!(inode->i_sb->s_flags & MS_ACTIVE))
901 goto out;
902
903 /*
904 * so now we have a nice long stream of locked
905 * and up to date pages, lets wait on them
906 */
907 for (i = 0; i < i_done; i++)
908 wait_on_page_writeback(pages[i]);
909
910 page_start = page_offset(pages[0]);
911 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
912
913 lock_extent_bits(&BTRFS_I(inode)->io_tree,
914 page_start, page_end - 1, 0, &cached_state,
915 GFP_NOFS);
916 ordered = btrfs_lookup_first_ordered_extent(inode, page_end - 1);
917 if (ordered &&
918 ordered->file_offset + ordered->len > page_start &&
919 ordered->file_offset < page_end) {
920 btrfs_put_ordered_extent(ordered);
921 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
922 page_start, page_end - 1,
923 &cached_state, GFP_NOFS);
924 for (i = 0; i < i_done; i++) {
925 unlock_page(pages[i]);
926 page_cache_release(pages[i]);
927 }
928 btrfs_wait_ordered_range(inode, page_start,
929 page_end - page_start);
930 goto again;
931 }
932 if (ordered)
933 btrfs_put_ordered_extent(ordered);
934
935 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
936 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
937 EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
938 GFP_NOFS);
939
940 if (i_done != num_pages) {
941 spin_lock(&BTRFS_I(inode)->lock);
942 BTRFS_I(inode)->outstanding_extents++;
943 spin_unlock(&BTRFS_I(inode)->lock);
944 btrfs_delalloc_release_space(inode,
945 (num_pages - i_done) << PAGE_CACHE_SHIFT);
946 }
947
948
949 btrfs_set_extent_delalloc(inode, page_start, page_end - 1,
950 &cached_state);
951
952 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
953 page_start, page_end - 1, &cached_state,
954 GFP_NOFS);
955
956 for (i = 0; i < i_done; i++) {
957 clear_page_dirty_for_io(pages[i]);
958 ClearPageChecked(pages[i]);
959 set_page_extent_mapped(pages[i]);
960 set_page_dirty(pages[i]);
961 unlock_page(pages[i]);
962 page_cache_release(pages[i]);
963 }
964 return i_done;
965 out:
966 for (i = 0; i < i_done; i++) {
967 unlock_page(pages[i]);
968 page_cache_release(pages[i]);
969 }
970 btrfs_delalloc_release_space(inode, num_pages << PAGE_CACHE_SHIFT);
971 return ret;
972
973 }
974
975 int btrfs_defrag_file(struct inode *inode, struct file *file,
976 struct btrfs_ioctl_defrag_range_args *range,
977 u64 newer_than, unsigned long max_to_defrag)
978 {
979 struct btrfs_root *root = BTRFS_I(inode)->root;
980 struct btrfs_super_block *disk_super;
981 struct file_ra_state *ra = NULL;
982 unsigned long last_index;
983 u64 features;
984 u64 last_len = 0;
985 u64 skip = 0;
986 u64 defrag_end = 0;
987 u64 newer_off = range->start;
988 int newer_left = 0;
989 unsigned long i;
990 int ret;
991 int defrag_count = 0;
992 int compress_type = BTRFS_COMPRESS_ZLIB;
993 int extent_thresh = range->extent_thresh;
994 int newer_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
995 u64 new_align = ~((u64)128 * 1024 - 1);
996 struct page **pages = NULL;
997
998 if (extent_thresh == 0)
999 extent_thresh = 256 * 1024;
1000
1001 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1002 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1003 return -EINVAL;
1004 if (range->compress_type)
1005 compress_type = range->compress_type;
1006 }
1007
1008 if (inode->i_size == 0)
1009 return 0;
1010
1011 /*
1012 * if we were not given a file, allocate a readahead
1013 * context
1014 */
1015 if (!file) {
1016 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1017 if (!ra)
1018 return -ENOMEM;
1019 file_ra_state_init(ra, inode->i_mapping);
1020 } else {
1021 ra = &file->f_ra;
1022 }
1023
1024 pages = kmalloc(sizeof(struct page *) * newer_cluster,
1025 GFP_NOFS);
1026 if (!pages) {
1027 ret = -ENOMEM;
1028 goto out_ra;
1029 }
1030
1031 /* find the last page to defrag */
1032 if (range->start + range->len > range->start) {
1033 last_index = min_t(u64, inode->i_size - 1,
1034 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1035 } else {
1036 last_index = (inode->i_size - 1) >> PAGE_CACHE_SHIFT;
1037 }
1038
1039 if (newer_than) {
1040 ret = find_new_extents(root, inode, newer_than,
1041 &newer_off, 64 * 1024);
1042 if (!ret) {
1043 range->start = newer_off;
1044 /*
1045 * we always align our defrag to help keep
1046 * the extents in the file evenly spaced
1047 */
1048 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1049 newer_left = newer_cluster;
1050 } else
1051 goto out_ra;
1052 } else {
1053 i = range->start >> PAGE_CACHE_SHIFT;
1054 }
1055 if (!max_to_defrag)
1056 max_to_defrag = last_index - 1;
1057
1058 /*
1059 * make writeback starts from i, so the defrag range can be
1060 * written sequentially.
1061 */
1062 if (i < inode->i_mapping->writeback_index)
1063 inode->i_mapping->writeback_index = i;
1064
1065 while (i <= last_index && defrag_count < max_to_defrag &&
1066 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1067 PAGE_CACHE_SHIFT)) {
1068 /*
1069 * make sure we stop running if someone unmounts
1070 * the FS
1071 */
1072 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1073 break;
1074
1075 if (!newer_than &&
1076 !should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1077 PAGE_CACHE_SIZE,
1078 extent_thresh,
1079 &last_len, &skip,
1080 &defrag_end)) {
1081 unsigned long next;
1082 /*
1083 * the should_defrag function tells us how much to skip
1084 * bump our counter by the suggested amount
1085 */
1086 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1087 i = max(i + 1, next);
1088 continue;
1089 }
1090 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1091 BTRFS_I(inode)->force_compress = compress_type;
1092
1093 btrfs_force_ra(inode->i_mapping, ra, file, i, newer_cluster);
1094
1095 ret = cluster_pages_for_defrag(inode, pages, i, newer_cluster);
1096 if (ret < 0)
1097 goto out_ra;
1098
1099 defrag_count += ret;
1100 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
1101 i += ret;
1102
1103 if (newer_than) {
1104 if (newer_off == (u64)-1)
1105 break;
1106
1107 newer_off = max(newer_off + 1,
1108 (u64)i << PAGE_CACHE_SHIFT);
1109
1110 ret = find_new_extents(root, inode,
1111 newer_than, &newer_off,
1112 64 * 1024);
1113 if (!ret) {
1114 range->start = newer_off;
1115 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1116 newer_left = newer_cluster;
1117 } else {
1118 break;
1119 }
1120 } else {
1121 i++;
1122 }
1123 }
1124
1125 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1126 filemap_flush(inode->i_mapping);
1127
1128 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1129 /* the filemap_flush will queue IO into the worker threads, but
1130 * we have to make sure the IO is actually started and that
1131 * ordered extents get created before we return
1132 */
1133 atomic_inc(&root->fs_info->async_submit_draining);
1134 while (atomic_read(&root->fs_info->nr_async_submits) ||
1135 atomic_read(&root->fs_info->async_delalloc_pages)) {
1136 wait_event(root->fs_info->async_submit_wait,
1137 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1138 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1139 }
1140 atomic_dec(&root->fs_info->async_submit_draining);
1141
1142 mutex_lock(&inode->i_mutex);
1143 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1144 mutex_unlock(&inode->i_mutex);
1145 }
1146
1147 disk_super = &root->fs_info->super_copy;
1148 features = btrfs_super_incompat_flags(disk_super);
1149 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1150 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
1151 btrfs_set_super_incompat_flags(disk_super, features);
1152 }
1153
1154 if (!file)
1155 kfree(ra);
1156 return defrag_count;
1157
1158 out_ra:
1159 if (!file)
1160 kfree(ra);
1161 kfree(pages);
1162 return ret;
1163 }
1164
1165 static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
1166 void __user *arg)
1167 {
1168 u64 new_size;
1169 u64 old_size;
1170 u64 devid = 1;
1171 struct btrfs_ioctl_vol_args *vol_args;
1172 struct btrfs_trans_handle *trans;
1173 struct btrfs_device *device = NULL;
1174 char *sizestr;
1175 char *devstr = NULL;
1176 int ret = 0;
1177 int mod = 0;
1178
1179 if (root->fs_info->sb->s_flags & MS_RDONLY)
1180 return -EROFS;
1181
1182 if (!capable(CAP_SYS_ADMIN))
1183 return -EPERM;
1184
1185 vol_args = memdup_user(arg, sizeof(*vol_args));
1186 if (IS_ERR(vol_args))
1187 return PTR_ERR(vol_args);
1188
1189 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1190
1191 mutex_lock(&root->fs_info->volume_mutex);
1192 sizestr = vol_args->name;
1193 devstr = strchr(sizestr, ':');
1194 if (devstr) {
1195 char *end;
1196 sizestr = devstr + 1;
1197 *devstr = '\0';
1198 devstr = vol_args->name;
1199 devid = simple_strtoull(devstr, &end, 10);
1200 printk(KERN_INFO "resizing devid %llu\n",
1201 (unsigned long long)devid);
1202 }
1203 device = btrfs_find_device(root, devid, NULL, NULL);
1204 if (!device) {
1205 printk(KERN_INFO "resizer unable to find device %llu\n",
1206 (unsigned long long)devid);
1207 ret = -EINVAL;
1208 goto out_unlock;
1209 }
1210 if (!strcmp(sizestr, "max"))
1211 new_size = device->bdev->bd_inode->i_size;
1212 else {
1213 if (sizestr[0] == '-') {
1214 mod = -1;
1215 sizestr++;
1216 } else if (sizestr[0] == '+') {
1217 mod = 1;
1218 sizestr++;
1219 }
1220 new_size = memparse(sizestr, NULL);
1221 if (new_size == 0) {
1222 ret = -EINVAL;
1223 goto out_unlock;
1224 }
1225 }
1226
1227 old_size = device->total_bytes;
1228
1229 if (mod < 0) {
1230 if (new_size > old_size) {
1231 ret = -EINVAL;
1232 goto out_unlock;
1233 }
1234 new_size = old_size - new_size;
1235 } else if (mod > 0) {
1236 new_size = old_size + new_size;
1237 }
1238
1239 if (new_size < 256 * 1024 * 1024) {
1240 ret = -EINVAL;
1241 goto out_unlock;
1242 }
1243 if (new_size > device->bdev->bd_inode->i_size) {
1244 ret = -EFBIG;
1245 goto out_unlock;
1246 }
1247
1248 do_div(new_size, root->sectorsize);
1249 new_size *= root->sectorsize;
1250
1251 printk(KERN_INFO "new size for %s is %llu\n",
1252 device->name, (unsigned long long)new_size);
1253
1254 if (new_size > old_size) {
1255 trans = btrfs_start_transaction(root, 0);
1256 if (IS_ERR(trans)) {
1257 ret = PTR_ERR(trans);
1258 goto out_unlock;
1259 }
1260 ret = btrfs_grow_device(trans, device, new_size);
1261 btrfs_commit_transaction(trans, root);
1262 } else {
1263 ret = btrfs_shrink_device(device, new_size);
1264 }
1265
1266 out_unlock:
1267 mutex_unlock(&root->fs_info->volume_mutex);
1268 kfree(vol_args);
1269 return ret;
1270 }
1271
1272 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1273 char *name,
1274 unsigned long fd,
1275 int subvol,
1276 u64 *transid,
1277 bool readonly)
1278 {
1279 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1280 struct file *src_file;
1281 int namelen;
1282 int ret = 0;
1283
1284 if (root->fs_info->sb->s_flags & MS_RDONLY)
1285 return -EROFS;
1286
1287 namelen = strlen(name);
1288 if (strchr(name, '/')) {
1289 ret = -EINVAL;
1290 goto out;
1291 }
1292
1293 if (subvol) {
1294 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1295 NULL, transid, readonly);
1296 } else {
1297 struct inode *src_inode;
1298 src_file = fget(fd);
1299 if (!src_file) {
1300 ret = -EINVAL;
1301 goto out;
1302 }
1303
1304 src_inode = src_file->f_path.dentry->d_inode;
1305 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1306 printk(KERN_INFO "btrfs: Snapshot src from "
1307 "another FS\n");
1308 ret = -EINVAL;
1309 fput(src_file);
1310 goto out;
1311 }
1312 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1313 BTRFS_I(src_inode)->root,
1314 transid, readonly);
1315 fput(src_file);
1316 }
1317 out:
1318 return ret;
1319 }
1320
1321 static noinline int btrfs_ioctl_snap_create(struct file *file,
1322 void __user *arg, int subvol)
1323 {
1324 struct btrfs_ioctl_vol_args *vol_args;
1325 int ret;
1326
1327 vol_args = memdup_user(arg, sizeof(*vol_args));
1328 if (IS_ERR(vol_args))
1329 return PTR_ERR(vol_args);
1330 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1331
1332 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1333 vol_args->fd, subvol,
1334 NULL, false);
1335
1336 kfree(vol_args);
1337 return ret;
1338 }
1339
1340 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1341 void __user *arg, int subvol)
1342 {
1343 struct btrfs_ioctl_vol_args_v2 *vol_args;
1344 int ret;
1345 u64 transid = 0;
1346 u64 *ptr = NULL;
1347 bool readonly = false;
1348
1349 vol_args = memdup_user(arg, sizeof(*vol_args));
1350 if (IS_ERR(vol_args))
1351 return PTR_ERR(vol_args);
1352 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1353
1354 if (vol_args->flags &
1355 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
1356 ret = -EOPNOTSUPP;
1357 goto out;
1358 }
1359
1360 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1361 ptr = &transid;
1362 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1363 readonly = true;
1364
1365 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1366 vol_args->fd, subvol,
1367 ptr, readonly);
1368
1369 if (ret == 0 && ptr &&
1370 copy_to_user(arg +
1371 offsetof(struct btrfs_ioctl_vol_args_v2,
1372 transid), ptr, sizeof(*ptr)))
1373 ret = -EFAULT;
1374 out:
1375 kfree(vol_args);
1376 return ret;
1377 }
1378
1379 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1380 void __user *arg)
1381 {
1382 struct inode *inode = fdentry(file)->d_inode;
1383 struct btrfs_root *root = BTRFS_I(inode)->root;
1384 int ret = 0;
1385 u64 flags = 0;
1386
1387 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1388 return -EINVAL;
1389
1390 down_read(&root->fs_info->subvol_sem);
1391 if (btrfs_root_readonly(root))
1392 flags |= BTRFS_SUBVOL_RDONLY;
1393 up_read(&root->fs_info->subvol_sem);
1394
1395 if (copy_to_user(arg, &flags, sizeof(flags)))
1396 ret = -EFAULT;
1397
1398 return ret;
1399 }
1400
1401 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1402 void __user *arg)
1403 {
1404 struct inode *inode = fdentry(file)->d_inode;
1405 struct btrfs_root *root = BTRFS_I(inode)->root;
1406 struct btrfs_trans_handle *trans;
1407 u64 root_flags;
1408 u64 flags;
1409 int ret = 0;
1410
1411 if (root->fs_info->sb->s_flags & MS_RDONLY)
1412 return -EROFS;
1413
1414 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1415 return -EINVAL;
1416
1417 if (copy_from_user(&flags, arg, sizeof(flags)))
1418 return -EFAULT;
1419
1420 if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
1421 return -EINVAL;
1422
1423 if (flags & ~BTRFS_SUBVOL_RDONLY)
1424 return -EOPNOTSUPP;
1425
1426 if (!inode_owner_or_capable(inode))
1427 return -EACCES;
1428
1429 down_write(&root->fs_info->subvol_sem);
1430
1431 /* nothing to do */
1432 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1433 goto out;
1434
1435 root_flags = btrfs_root_flags(&root->root_item);
1436 if (flags & BTRFS_SUBVOL_RDONLY)
1437 btrfs_set_root_flags(&root->root_item,
1438 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1439 else
1440 btrfs_set_root_flags(&root->root_item,
1441 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1442
1443 trans = btrfs_start_transaction(root, 1);
1444 if (IS_ERR(trans)) {
1445 ret = PTR_ERR(trans);
1446 goto out_reset;
1447 }
1448
1449 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1450 &root->root_key, &root->root_item);
1451
1452 btrfs_commit_transaction(trans, root);
1453 out_reset:
1454 if (ret)
1455 btrfs_set_root_flags(&root->root_item, root_flags);
1456 out:
1457 up_write(&root->fs_info->subvol_sem);
1458 return ret;
1459 }
1460
1461 /*
1462 * helper to check if the subvolume references other subvolumes
1463 */
1464 static noinline int may_destroy_subvol(struct btrfs_root *root)
1465 {
1466 struct btrfs_path *path;
1467 struct btrfs_key key;
1468 int ret;
1469
1470 path = btrfs_alloc_path();
1471 if (!path)
1472 return -ENOMEM;
1473
1474 key.objectid = root->root_key.objectid;
1475 key.type = BTRFS_ROOT_REF_KEY;
1476 key.offset = (u64)-1;
1477
1478 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1479 &key, path, 0, 0);
1480 if (ret < 0)
1481 goto out;
1482 BUG_ON(ret == 0);
1483
1484 ret = 0;
1485 if (path->slots[0] > 0) {
1486 path->slots[0]--;
1487 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1488 if (key.objectid == root->root_key.objectid &&
1489 key.type == BTRFS_ROOT_REF_KEY)
1490 ret = -ENOTEMPTY;
1491 }
1492 out:
1493 btrfs_free_path(path);
1494 return ret;
1495 }
1496
1497 static noinline int key_in_sk(struct btrfs_key *key,
1498 struct btrfs_ioctl_search_key *sk)
1499 {
1500 struct btrfs_key test;
1501 int ret;
1502
1503 test.objectid = sk->min_objectid;
1504 test.type = sk->min_type;
1505 test.offset = sk->min_offset;
1506
1507 ret = btrfs_comp_cpu_keys(key, &test);
1508 if (ret < 0)
1509 return 0;
1510
1511 test.objectid = sk->max_objectid;
1512 test.type = sk->max_type;
1513 test.offset = sk->max_offset;
1514
1515 ret = btrfs_comp_cpu_keys(key, &test);
1516 if (ret > 0)
1517 return 0;
1518 return 1;
1519 }
1520
1521 static noinline int copy_to_sk(struct btrfs_root *root,
1522 struct btrfs_path *path,
1523 struct btrfs_key *key,
1524 struct btrfs_ioctl_search_key *sk,
1525 char *buf,
1526 unsigned long *sk_offset,
1527 int *num_found)
1528 {
1529 u64 found_transid;
1530 struct extent_buffer *leaf;
1531 struct btrfs_ioctl_search_header sh;
1532 unsigned long item_off;
1533 unsigned long item_len;
1534 int nritems;
1535 int i;
1536 int slot;
1537 int ret = 0;
1538
1539 leaf = path->nodes[0];
1540 slot = path->slots[0];
1541 nritems = btrfs_header_nritems(leaf);
1542
1543 if (btrfs_header_generation(leaf) > sk->max_transid) {
1544 i = nritems;
1545 goto advance_key;
1546 }
1547 found_transid = btrfs_header_generation(leaf);
1548
1549 for (i = slot; i < nritems; i++) {
1550 item_off = btrfs_item_ptr_offset(leaf, i);
1551 item_len = btrfs_item_size_nr(leaf, i);
1552
1553 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1554 item_len = 0;
1555
1556 if (sizeof(sh) + item_len + *sk_offset >
1557 BTRFS_SEARCH_ARGS_BUFSIZE) {
1558 ret = 1;
1559 goto overflow;
1560 }
1561
1562 btrfs_item_key_to_cpu(leaf, key, i);
1563 if (!key_in_sk(key, sk))
1564 continue;
1565
1566 sh.objectid = key->objectid;
1567 sh.offset = key->offset;
1568 sh.type = key->type;
1569 sh.len = item_len;
1570 sh.transid = found_transid;
1571
1572 /* copy search result header */
1573 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1574 *sk_offset += sizeof(sh);
1575
1576 if (item_len) {
1577 char *p = buf + *sk_offset;
1578 /* copy the item */
1579 read_extent_buffer(leaf, p,
1580 item_off, item_len);
1581 *sk_offset += item_len;
1582 }
1583 (*num_found)++;
1584
1585 if (*num_found >= sk->nr_items)
1586 break;
1587 }
1588 advance_key:
1589 ret = 0;
1590 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1591 key->offset++;
1592 else if (key->type < (u8)-1 && key->type < sk->max_type) {
1593 key->offset = 0;
1594 key->type++;
1595 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1596 key->offset = 0;
1597 key->type = 0;
1598 key->objectid++;
1599 } else
1600 ret = 1;
1601 overflow:
1602 return ret;
1603 }
1604
1605 static noinline int search_ioctl(struct inode *inode,
1606 struct btrfs_ioctl_search_args *args)
1607 {
1608 struct btrfs_root *root;
1609 struct btrfs_key key;
1610 struct btrfs_key max_key;
1611 struct btrfs_path *path;
1612 struct btrfs_ioctl_search_key *sk = &args->key;
1613 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1614 int ret;
1615 int num_found = 0;
1616 unsigned long sk_offset = 0;
1617
1618 path = btrfs_alloc_path();
1619 if (!path)
1620 return -ENOMEM;
1621
1622 if (sk->tree_id == 0) {
1623 /* search the root of the inode that was passed */
1624 root = BTRFS_I(inode)->root;
1625 } else {
1626 key.objectid = sk->tree_id;
1627 key.type = BTRFS_ROOT_ITEM_KEY;
1628 key.offset = (u64)-1;
1629 root = btrfs_read_fs_root_no_name(info, &key);
1630 if (IS_ERR(root)) {
1631 printk(KERN_ERR "could not find root %llu\n",
1632 sk->tree_id);
1633 btrfs_free_path(path);
1634 return -ENOENT;
1635 }
1636 }
1637
1638 key.objectid = sk->min_objectid;
1639 key.type = sk->min_type;
1640 key.offset = sk->min_offset;
1641
1642 max_key.objectid = sk->max_objectid;
1643 max_key.type = sk->max_type;
1644 max_key.offset = sk->max_offset;
1645
1646 path->keep_locks = 1;
1647
1648 while(1) {
1649 ret = btrfs_search_forward(root, &key, &max_key, path, 0,
1650 sk->min_transid);
1651 if (ret != 0) {
1652 if (ret > 0)
1653 ret = 0;
1654 goto err;
1655 }
1656 ret = copy_to_sk(root, path, &key, sk, args->buf,
1657 &sk_offset, &num_found);
1658 btrfs_release_path(path);
1659 if (ret || num_found >= sk->nr_items)
1660 break;
1661
1662 }
1663 ret = 0;
1664 err:
1665 sk->nr_items = num_found;
1666 btrfs_free_path(path);
1667 return ret;
1668 }
1669
1670 static noinline int btrfs_ioctl_tree_search(struct file *file,
1671 void __user *argp)
1672 {
1673 struct btrfs_ioctl_search_args *args;
1674 struct inode *inode;
1675 int ret;
1676
1677 if (!capable(CAP_SYS_ADMIN))
1678 return -EPERM;
1679
1680 args = memdup_user(argp, sizeof(*args));
1681 if (IS_ERR(args))
1682 return PTR_ERR(args);
1683
1684 inode = fdentry(file)->d_inode;
1685 ret = search_ioctl(inode, args);
1686 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1687 ret = -EFAULT;
1688 kfree(args);
1689 return ret;
1690 }
1691
1692 /*
1693 * Search INODE_REFs to identify path name of 'dirid' directory
1694 * in a 'tree_id' tree. and sets path name to 'name'.
1695 */
1696 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1697 u64 tree_id, u64 dirid, char *name)
1698 {
1699 struct btrfs_root *root;
1700 struct btrfs_key key;
1701 char *ptr;
1702 int ret = -1;
1703 int slot;
1704 int len;
1705 int total_len = 0;
1706 struct btrfs_inode_ref *iref;
1707 struct extent_buffer *l;
1708 struct btrfs_path *path;
1709
1710 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1711 name[0]='\0';
1712 return 0;
1713 }
1714
1715 path = btrfs_alloc_path();
1716 if (!path)
1717 return -ENOMEM;
1718
1719 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1720
1721 key.objectid = tree_id;
1722 key.type = BTRFS_ROOT_ITEM_KEY;
1723 key.offset = (u64)-1;
1724 root = btrfs_read_fs_root_no_name(info, &key);
1725 if (IS_ERR(root)) {
1726 printk(KERN_ERR "could not find root %llu\n", tree_id);
1727 ret = -ENOENT;
1728 goto out;
1729 }
1730
1731 key.objectid = dirid;
1732 key.type = BTRFS_INODE_REF_KEY;
1733 key.offset = (u64)-1;
1734
1735 while(1) {
1736 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1737 if (ret < 0)
1738 goto out;
1739
1740 l = path->nodes[0];
1741 slot = path->slots[0];
1742 if (ret > 0 && slot > 0)
1743 slot--;
1744 btrfs_item_key_to_cpu(l, &key, slot);
1745
1746 if (ret > 0 && (key.objectid != dirid ||
1747 key.type != BTRFS_INODE_REF_KEY)) {
1748 ret = -ENOENT;
1749 goto out;
1750 }
1751
1752 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1753 len = btrfs_inode_ref_name_len(l, iref);
1754 ptr -= len + 1;
1755 total_len += len + 1;
1756 if (ptr < name)
1757 goto out;
1758
1759 *(ptr + len) = '/';
1760 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1761
1762 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1763 break;
1764
1765 btrfs_release_path(path);
1766 key.objectid = key.offset;
1767 key.offset = (u64)-1;
1768 dirid = key.objectid;
1769 }
1770 if (ptr < name)
1771 goto out;
1772 memmove(name, ptr, total_len);
1773 name[total_len]='\0';
1774 ret = 0;
1775 out:
1776 btrfs_free_path(path);
1777 return ret;
1778 }
1779
1780 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
1781 void __user *argp)
1782 {
1783 struct btrfs_ioctl_ino_lookup_args *args;
1784 struct inode *inode;
1785 int ret;
1786
1787 if (!capable(CAP_SYS_ADMIN))
1788 return -EPERM;
1789
1790 args = memdup_user(argp, sizeof(*args));
1791 if (IS_ERR(args))
1792 return PTR_ERR(args);
1793
1794 inode = fdentry(file)->d_inode;
1795
1796 if (args->treeid == 0)
1797 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
1798
1799 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
1800 args->treeid, args->objectid,
1801 args->name);
1802
1803 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1804 ret = -EFAULT;
1805
1806 kfree(args);
1807 return ret;
1808 }
1809
1810 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
1811 void __user *arg)
1812 {
1813 struct dentry *parent = fdentry(file);
1814 struct dentry *dentry;
1815 struct inode *dir = parent->d_inode;
1816 struct inode *inode;
1817 struct btrfs_root *root = BTRFS_I(dir)->root;
1818 struct btrfs_root *dest = NULL;
1819 struct btrfs_ioctl_vol_args *vol_args;
1820 struct btrfs_trans_handle *trans;
1821 int namelen;
1822 int ret;
1823 int err = 0;
1824
1825 vol_args = memdup_user(arg, sizeof(*vol_args));
1826 if (IS_ERR(vol_args))
1827 return PTR_ERR(vol_args);
1828
1829 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1830 namelen = strlen(vol_args->name);
1831 if (strchr(vol_args->name, '/') ||
1832 strncmp(vol_args->name, "..", namelen) == 0) {
1833 err = -EINVAL;
1834 goto out;
1835 }
1836
1837 err = mnt_want_write(file->f_path.mnt);
1838 if (err)
1839 goto out;
1840
1841 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
1842 dentry = lookup_one_len(vol_args->name, parent, namelen);
1843 if (IS_ERR(dentry)) {
1844 err = PTR_ERR(dentry);
1845 goto out_unlock_dir;
1846 }
1847
1848 if (!dentry->d_inode) {
1849 err = -ENOENT;
1850 goto out_dput;
1851 }
1852
1853 inode = dentry->d_inode;
1854 dest = BTRFS_I(inode)->root;
1855 if (!capable(CAP_SYS_ADMIN)){
1856 /*
1857 * Regular user. Only allow this with a special mount
1858 * option, when the user has write+exec access to the
1859 * subvol root, and when rmdir(2) would have been
1860 * allowed.
1861 *
1862 * Note that this is _not_ check that the subvol is
1863 * empty or doesn't contain data that we wouldn't
1864 * otherwise be able to delete.
1865 *
1866 * Users who want to delete empty subvols should try
1867 * rmdir(2).
1868 */
1869 err = -EPERM;
1870 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
1871 goto out_dput;
1872
1873 /*
1874 * Do not allow deletion if the parent dir is the same
1875 * as the dir to be deleted. That means the ioctl
1876 * must be called on the dentry referencing the root
1877 * of the subvol, not a random directory contained
1878 * within it.
1879 */
1880 err = -EINVAL;
1881 if (root == dest)
1882 goto out_dput;
1883
1884 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
1885 if (err)
1886 goto out_dput;
1887
1888 /* check if subvolume may be deleted by a non-root user */
1889 err = btrfs_may_delete(dir, dentry, 1);
1890 if (err)
1891 goto out_dput;
1892 }
1893
1894 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1895 err = -EINVAL;
1896 goto out_dput;
1897 }
1898
1899 mutex_lock(&inode->i_mutex);
1900 err = d_invalidate(dentry);
1901 if (err)
1902 goto out_unlock;
1903
1904 down_write(&root->fs_info->subvol_sem);
1905
1906 err = may_destroy_subvol(dest);
1907 if (err)
1908 goto out_up_write;
1909
1910 trans = btrfs_start_transaction(root, 0);
1911 if (IS_ERR(trans)) {
1912 err = PTR_ERR(trans);
1913 goto out_up_write;
1914 }
1915 trans->block_rsv = &root->fs_info->global_block_rsv;
1916
1917 ret = btrfs_unlink_subvol(trans, root, dir,
1918 dest->root_key.objectid,
1919 dentry->d_name.name,
1920 dentry->d_name.len);
1921 BUG_ON(ret);
1922
1923 btrfs_record_root_in_trans(trans, dest);
1924
1925 memset(&dest->root_item.drop_progress, 0,
1926 sizeof(dest->root_item.drop_progress));
1927 dest->root_item.drop_level = 0;
1928 btrfs_set_root_refs(&dest->root_item, 0);
1929
1930 if (!xchg(&dest->orphan_item_inserted, 1)) {
1931 ret = btrfs_insert_orphan_item(trans,
1932 root->fs_info->tree_root,
1933 dest->root_key.objectid);
1934 BUG_ON(ret);
1935 }
1936
1937 ret = btrfs_end_transaction(trans, root);
1938 BUG_ON(ret);
1939 inode->i_flags |= S_DEAD;
1940 out_up_write:
1941 up_write(&root->fs_info->subvol_sem);
1942 out_unlock:
1943 mutex_unlock(&inode->i_mutex);
1944 if (!err) {
1945 shrink_dcache_sb(root->fs_info->sb);
1946 btrfs_invalidate_inodes(dest);
1947 d_delete(dentry);
1948 }
1949 out_dput:
1950 dput(dentry);
1951 out_unlock_dir:
1952 mutex_unlock(&dir->i_mutex);
1953 mnt_drop_write(file->f_path.mnt);
1954 out:
1955 kfree(vol_args);
1956 return err;
1957 }
1958
1959 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
1960 {
1961 struct inode *inode = fdentry(file)->d_inode;
1962 struct btrfs_root *root = BTRFS_I(inode)->root;
1963 struct btrfs_ioctl_defrag_range_args *range;
1964 int ret;
1965
1966 if (btrfs_root_readonly(root))
1967 return -EROFS;
1968
1969 ret = mnt_want_write(file->f_path.mnt);
1970 if (ret)
1971 return ret;
1972
1973 switch (inode->i_mode & S_IFMT) {
1974 case S_IFDIR:
1975 if (!capable(CAP_SYS_ADMIN)) {
1976 ret = -EPERM;
1977 goto out;
1978 }
1979 ret = btrfs_defrag_root(root, 0);
1980 if (ret)
1981 goto out;
1982 ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
1983 break;
1984 case S_IFREG:
1985 if (!(file->f_mode & FMODE_WRITE)) {
1986 ret = -EINVAL;
1987 goto out;
1988 }
1989
1990 range = kzalloc(sizeof(*range), GFP_KERNEL);
1991 if (!range) {
1992 ret = -ENOMEM;
1993 goto out;
1994 }
1995
1996 if (argp) {
1997 if (copy_from_user(range, argp,
1998 sizeof(*range))) {
1999 ret = -EFAULT;
2000 kfree(range);
2001 goto out;
2002 }
2003 /* compression requires us to start the IO */
2004 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2005 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2006 range->extent_thresh = (u32)-1;
2007 }
2008 } else {
2009 /* the rest are all set to zero by kzalloc */
2010 range->len = (u64)-1;
2011 }
2012 ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
2013 range, 0, 0);
2014 if (ret > 0)
2015 ret = 0;
2016 kfree(range);
2017 break;
2018 default:
2019 ret = -EINVAL;
2020 }
2021 out:
2022 mnt_drop_write(file->f_path.mnt);
2023 return ret;
2024 }
2025
2026 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2027 {
2028 struct btrfs_ioctl_vol_args *vol_args;
2029 int ret;
2030
2031 if (!capable(CAP_SYS_ADMIN))
2032 return -EPERM;
2033
2034 vol_args = memdup_user(arg, sizeof(*vol_args));
2035 if (IS_ERR(vol_args))
2036 return PTR_ERR(vol_args);
2037
2038 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2039 ret = btrfs_init_new_device(root, vol_args->name);
2040
2041 kfree(vol_args);
2042 return ret;
2043 }
2044
2045 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
2046 {
2047 struct btrfs_ioctl_vol_args *vol_args;
2048 int ret;
2049
2050 if (!capable(CAP_SYS_ADMIN))
2051 return -EPERM;
2052
2053 if (root->fs_info->sb->s_flags & MS_RDONLY)
2054 return -EROFS;
2055
2056 vol_args = memdup_user(arg, sizeof(*vol_args));
2057 if (IS_ERR(vol_args))
2058 return PTR_ERR(vol_args);
2059
2060 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2061 ret = btrfs_rm_device(root, vol_args->name);
2062
2063 kfree(vol_args);
2064 return ret;
2065 }
2066
2067 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2068 {
2069 struct btrfs_ioctl_fs_info_args *fi_args;
2070 struct btrfs_device *device;
2071 struct btrfs_device *next;
2072 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2073 int ret = 0;
2074
2075 if (!capable(CAP_SYS_ADMIN))
2076 return -EPERM;
2077
2078 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2079 if (!fi_args)
2080 return -ENOMEM;
2081
2082 fi_args->num_devices = fs_devices->num_devices;
2083 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2084
2085 mutex_lock(&fs_devices->device_list_mutex);
2086 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2087 if (device->devid > fi_args->max_id)
2088 fi_args->max_id = device->devid;
2089 }
2090 mutex_unlock(&fs_devices->device_list_mutex);
2091
2092 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2093 ret = -EFAULT;
2094
2095 kfree(fi_args);
2096 return ret;
2097 }
2098
2099 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2100 {
2101 struct btrfs_ioctl_dev_info_args *di_args;
2102 struct btrfs_device *dev;
2103 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2104 int ret = 0;
2105 char *s_uuid = NULL;
2106 char empty_uuid[BTRFS_UUID_SIZE] = {0};
2107
2108 if (!capable(CAP_SYS_ADMIN))
2109 return -EPERM;
2110
2111 di_args = memdup_user(arg, sizeof(*di_args));
2112 if (IS_ERR(di_args))
2113 return PTR_ERR(di_args);
2114
2115 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2116 s_uuid = di_args->uuid;
2117
2118 mutex_lock(&fs_devices->device_list_mutex);
2119 dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL);
2120 mutex_unlock(&fs_devices->device_list_mutex);
2121
2122 if (!dev) {
2123 ret = -ENODEV;
2124 goto out;
2125 }
2126
2127 di_args->devid = dev->devid;
2128 di_args->bytes_used = dev->bytes_used;
2129 di_args->total_bytes = dev->total_bytes;
2130 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2131 strncpy(di_args->path, dev->name, sizeof(di_args->path));
2132
2133 out:
2134 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2135 ret = -EFAULT;
2136
2137 kfree(di_args);
2138 return ret;
2139 }
2140
2141 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2142 u64 off, u64 olen, u64 destoff)
2143 {
2144 struct inode *inode = fdentry(file)->d_inode;
2145 struct btrfs_root *root = BTRFS_I(inode)->root;
2146 struct file *src_file;
2147 struct inode *src;
2148 struct btrfs_trans_handle *trans;
2149 struct btrfs_path *path;
2150 struct extent_buffer *leaf;
2151 char *buf;
2152 struct btrfs_key key;
2153 u32 nritems;
2154 int slot;
2155 int ret;
2156 u64 len = olen;
2157 u64 bs = root->fs_info->sb->s_blocksize;
2158 u64 hint_byte;
2159
2160 /*
2161 * TODO:
2162 * - split compressed inline extents. annoying: we need to
2163 * decompress into destination's address_space (the file offset
2164 * may change, so source mapping won't do), then recompress (or
2165 * otherwise reinsert) a subrange.
2166 * - allow ranges within the same file to be cloned (provided
2167 * they don't overlap)?
2168 */
2169
2170 /* the destination must be opened for writing */
2171 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2172 return -EINVAL;
2173
2174 if (btrfs_root_readonly(root))
2175 return -EROFS;
2176
2177 ret = mnt_want_write(file->f_path.mnt);
2178 if (ret)
2179 return ret;
2180
2181 src_file = fget(srcfd);
2182 if (!src_file) {
2183 ret = -EBADF;
2184 goto out_drop_write;
2185 }
2186
2187 src = src_file->f_dentry->d_inode;
2188
2189 ret = -EINVAL;
2190 if (src == inode)
2191 goto out_fput;
2192
2193 /* the src must be open for reading */
2194 if (!(src_file->f_mode & FMODE_READ))
2195 goto out_fput;
2196
2197 /* don't make the dst file partly checksummed */
2198 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2199 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2200 goto out_fput;
2201
2202 ret = -EISDIR;
2203 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2204 goto out_fput;
2205
2206 ret = -EXDEV;
2207 if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
2208 goto out_fput;
2209
2210 ret = -ENOMEM;
2211 buf = vmalloc(btrfs_level_size(root, 0));
2212 if (!buf)
2213 goto out_fput;
2214
2215 path = btrfs_alloc_path();
2216 if (!path) {
2217 vfree(buf);
2218 goto out_fput;
2219 }
2220 path->reada = 2;
2221
2222 if (inode < src) {
2223 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2224 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2225 } else {
2226 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2227 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2228 }
2229
2230 /* determine range to clone */
2231 ret = -EINVAL;
2232 if (off + len > src->i_size || off + len < off)
2233 goto out_unlock;
2234 if (len == 0)
2235 olen = len = src->i_size - off;
2236 /* if we extend to eof, continue to block boundary */
2237 if (off + len == src->i_size)
2238 len = ALIGN(src->i_size, bs) - off;
2239
2240 /* verify the end result is block aligned */
2241 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2242 !IS_ALIGNED(destoff, bs))
2243 goto out_unlock;
2244
2245 if (destoff > inode->i_size) {
2246 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2247 if (ret)
2248 goto out_unlock;
2249 }
2250
2251 /* truncate page cache pages from target inode range */
2252 truncate_inode_pages_range(&inode->i_data, destoff,
2253 PAGE_CACHE_ALIGN(destoff + len) - 1);
2254
2255 /* do any pending delalloc/csum calc on src, one way or
2256 another, and lock file content */
2257 while (1) {
2258 struct btrfs_ordered_extent *ordered;
2259 lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2260 ordered = btrfs_lookup_first_ordered_extent(src, off+len);
2261 if (!ordered &&
2262 !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len,
2263 EXTENT_DELALLOC, 0, NULL))
2264 break;
2265 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2266 if (ordered)
2267 btrfs_put_ordered_extent(ordered);
2268 btrfs_wait_ordered_range(src, off, len);
2269 }
2270
2271 /* clone data */
2272 key.objectid = btrfs_ino(src);
2273 key.type = BTRFS_EXTENT_DATA_KEY;
2274 key.offset = 0;
2275
2276 while (1) {
2277 /*
2278 * note the key will change type as we walk through the
2279 * tree.
2280 */
2281 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2282 if (ret < 0)
2283 goto out;
2284
2285 nritems = btrfs_header_nritems(path->nodes[0]);
2286 if (path->slots[0] >= nritems) {
2287 ret = btrfs_next_leaf(root, path);
2288 if (ret < 0)
2289 goto out;
2290 if (ret > 0)
2291 break;
2292 nritems = btrfs_header_nritems(path->nodes[0]);
2293 }
2294 leaf = path->nodes[0];
2295 slot = path->slots[0];
2296
2297 btrfs_item_key_to_cpu(leaf, &key, slot);
2298 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2299 key.objectid != btrfs_ino(src))
2300 break;
2301
2302 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2303 struct btrfs_file_extent_item *extent;
2304 int type;
2305 u32 size;
2306 struct btrfs_key new_key;
2307 u64 disko = 0, diskl = 0;
2308 u64 datao = 0, datal = 0;
2309 u8 comp;
2310 u64 endoff;
2311
2312 size = btrfs_item_size_nr(leaf, slot);
2313 read_extent_buffer(leaf, buf,
2314 btrfs_item_ptr_offset(leaf, slot),
2315 size);
2316
2317 extent = btrfs_item_ptr(leaf, slot,
2318 struct btrfs_file_extent_item);
2319 comp = btrfs_file_extent_compression(leaf, extent);
2320 type = btrfs_file_extent_type(leaf, extent);
2321 if (type == BTRFS_FILE_EXTENT_REG ||
2322 type == BTRFS_FILE_EXTENT_PREALLOC) {
2323 disko = btrfs_file_extent_disk_bytenr(leaf,
2324 extent);
2325 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2326 extent);
2327 datao = btrfs_file_extent_offset(leaf, extent);
2328 datal = btrfs_file_extent_num_bytes(leaf,
2329 extent);
2330 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2331 /* take upper bound, may be compressed */
2332 datal = btrfs_file_extent_ram_bytes(leaf,
2333 extent);
2334 }
2335 btrfs_release_path(path);
2336
2337 if (key.offset + datal <= off ||
2338 key.offset >= off+len)
2339 goto next;
2340
2341 memcpy(&new_key, &key, sizeof(new_key));
2342 new_key.objectid = btrfs_ino(inode);
2343 if (off <= key.offset)
2344 new_key.offset = key.offset + destoff - off;
2345 else
2346 new_key.offset = destoff;
2347
2348 /*
2349 * 1 - adjusting old extent (we may have to split it)
2350 * 1 - add new extent
2351 * 1 - inode update
2352 */
2353 trans = btrfs_start_transaction(root, 3);
2354 if (IS_ERR(trans)) {
2355 ret = PTR_ERR(trans);
2356 goto out;
2357 }
2358
2359 if (type == BTRFS_FILE_EXTENT_REG ||
2360 type == BTRFS_FILE_EXTENT_PREALLOC) {
2361 /*
2362 * a | --- range to clone ---| b
2363 * | ------------- extent ------------- |
2364 */
2365
2366 /* substract range b */
2367 if (key.offset + datal > off + len)
2368 datal = off + len - key.offset;
2369
2370 /* substract range a */
2371 if (off > key.offset) {
2372 datao += off - key.offset;
2373 datal -= off - key.offset;
2374 }
2375
2376 ret = btrfs_drop_extents(trans, inode,
2377 new_key.offset,
2378 new_key.offset + datal,
2379 &hint_byte, 1);
2380 BUG_ON(ret);
2381
2382 ret = btrfs_insert_empty_item(trans, root, path,
2383 &new_key, size);
2384 BUG_ON(ret);
2385
2386 leaf = path->nodes[0];
2387 slot = path->slots[0];
2388 write_extent_buffer(leaf, buf,
2389 btrfs_item_ptr_offset(leaf, slot),
2390 size);
2391
2392 extent = btrfs_item_ptr(leaf, slot,
2393 struct btrfs_file_extent_item);
2394
2395 /* disko == 0 means it's a hole */
2396 if (!disko)
2397 datao = 0;
2398
2399 btrfs_set_file_extent_offset(leaf, extent,
2400 datao);
2401 btrfs_set_file_extent_num_bytes(leaf, extent,
2402 datal);
2403 if (disko) {
2404 inode_add_bytes(inode, datal);
2405 ret = btrfs_inc_extent_ref(trans, root,
2406 disko, diskl, 0,
2407 root->root_key.objectid,
2408 btrfs_ino(inode),
2409 new_key.offset - datao);
2410 BUG_ON(ret);
2411 }
2412 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2413 u64 skip = 0;
2414 u64 trim = 0;
2415 if (off > key.offset) {
2416 skip = off - key.offset;
2417 new_key.offset += skip;
2418 }
2419
2420 if (key.offset + datal > off+len)
2421 trim = key.offset + datal - (off+len);
2422
2423 if (comp && (skip || trim)) {
2424 ret = -EINVAL;
2425 btrfs_end_transaction(trans, root);
2426 goto out;
2427 }
2428 size -= skip + trim;
2429 datal -= skip + trim;
2430
2431 ret = btrfs_drop_extents(trans, inode,
2432 new_key.offset,
2433 new_key.offset + datal,
2434 &hint_byte, 1);
2435 BUG_ON(ret);
2436
2437 ret = btrfs_insert_empty_item(trans, root, path,
2438 &new_key, size);
2439 BUG_ON(ret);
2440
2441 if (skip) {
2442 u32 start =
2443 btrfs_file_extent_calc_inline_size(0);
2444 memmove(buf+start, buf+start+skip,
2445 datal);
2446 }
2447
2448 leaf = path->nodes[0];
2449 slot = path->slots[0];
2450 write_extent_buffer(leaf, buf,
2451 btrfs_item_ptr_offset(leaf, slot),
2452 size);
2453 inode_add_bytes(inode, datal);
2454 }
2455
2456 btrfs_mark_buffer_dirty(leaf);
2457 btrfs_release_path(path);
2458
2459 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2460
2461 /*
2462 * we round up to the block size at eof when
2463 * determining which extents to clone above,
2464 * but shouldn't round up the file size
2465 */
2466 endoff = new_key.offset + datal;
2467 if (endoff > destoff+olen)
2468 endoff = destoff+olen;
2469 if (endoff > inode->i_size)
2470 btrfs_i_size_write(inode, endoff);
2471
2472 ret = btrfs_update_inode(trans, root, inode);
2473 BUG_ON(ret);
2474 btrfs_end_transaction(trans, root);
2475 }
2476 next:
2477 btrfs_release_path(path);
2478 key.offset++;
2479 }
2480 ret = 0;
2481 out:
2482 btrfs_release_path(path);
2483 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2484 out_unlock:
2485 mutex_unlock(&src->i_mutex);
2486 mutex_unlock(&inode->i_mutex);
2487 vfree(buf);
2488 btrfs_free_path(path);
2489 out_fput:
2490 fput(src_file);
2491 out_drop_write:
2492 mnt_drop_write(file->f_path.mnt);
2493 return ret;
2494 }
2495
2496 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2497 {
2498 struct btrfs_ioctl_clone_range_args args;
2499
2500 if (copy_from_user(&args, argp, sizeof(args)))
2501 return -EFAULT;
2502 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2503 args.src_length, args.dest_offset);
2504 }
2505
2506 /*
2507 * there are many ways the trans_start and trans_end ioctls can lead
2508 * to deadlocks. They should only be used by applications that
2509 * basically own the machine, and have a very in depth understanding
2510 * of all the possible deadlocks and enospc problems.
2511 */
2512 static long btrfs_ioctl_trans_start(struct file *file)
2513 {
2514 struct inode *inode = fdentry(file)->d_inode;
2515 struct btrfs_root *root = BTRFS_I(inode)->root;
2516 struct btrfs_trans_handle *trans;
2517 int ret;
2518
2519 ret = -EPERM;
2520 if (!capable(CAP_SYS_ADMIN))
2521 goto out;
2522
2523 ret = -EINPROGRESS;
2524 if (file->private_data)
2525 goto out;
2526
2527 ret = -EROFS;
2528 if (btrfs_root_readonly(root))
2529 goto out;
2530
2531 ret = mnt_want_write(file->f_path.mnt);
2532 if (ret)
2533 goto out;
2534
2535 atomic_inc(&root->fs_info->open_ioctl_trans);
2536
2537 ret = -ENOMEM;
2538 trans = btrfs_start_ioctl_transaction(root);
2539 if (IS_ERR(trans))
2540 goto out_drop;
2541
2542 file->private_data = trans;
2543 return 0;
2544
2545 out_drop:
2546 atomic_dec(&root->fs_info->open_ioctl_trans);
2547 mnt_drop_write(file->f_path.mnt);
2548 out:
2549 return ret;
2550 }
2551
2552 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2553 {
2554 struct inode *inode = fdentry(file)->d_inode;
2555 struct btrfs_root *root = BTRFS_I(inode)->root;
2556 struct btrfs_root *new_root;
2557 struct btrfs_dir_item *di;
2558 struct btrfs_trans_handle *trans;
2559 struct btrfs_path *path;
2560 struct btrfs_key location;
2561 struct btrfs_disk_key disk_key;
2562 struct btrfs_super_block *disk_super;
2563 u64 features;
2564 u64 objectid = 0;
2565 u64 dir_id;
2566
2567 if (!capable(CAP_SYS_ADMIN))
2568 return -EPERM;
2569
2570 if (copy_from_user(&objectid, argp, sizeof(objectid)))
2571 return -EFAULT;
2572
2573 if (!objectid)
2574 objectid = root->root_key.objectid;
2575
2576 location.objectid = objectid;
2577 location.type = BTRFS_ROOT_ITEM_KEY;
2578 location.offset = (u64)-1;
2579
2580 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2581 if (IS_ERR(new_root))
2582 return PTR_ERR(new_root);
2583
2584 if (btrfs_root_refs(&new_root->root_item) == 0)
2585 return -ENOENT;
2586
2587 path = btrfs_alloc_path();
2588 if (!path)
2589 return -ENOMEM;
2590 path->leave_spinning = 1;
2591
2592 trans = btrfs_start_transaction(root, 1);
2593 if (IS_ERR(trans)) {
2594 btrfs_free_path(path);
2595 return PTR_ERR(trans);
2596 }
2597
2598 dir_id = btrfs_super_root_dir(&root->fs_info->super_copy);
2599 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2600 dir_id, "default", 7, 1);
2601 if (IS_ERR_OR_NULL(di)) {
2602 btrfs_free_path(path);
2603 btrfs_end_transaction(trans, root);
2604 printk(KERN_ERR "Umm, you don't have the default dir item, "
2605 "this isn't going to work\n");
2606 return -ENOENT;
2607 }
2608
2609 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2610 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2611 btrfs_mark_buffer_dirty(path->nodes[0]);
2612 btrfs_free_path(path);
2613
2614 disk_super = &root->fs_info->super_copy;
2615 features = btrfs_super_incompat_flags(disk_super);
2616 if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) {
2617 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL;
2618 btrfs_set_super_incompat_flags(disk_super, features);
2619 }
2620 btrfs_end_transaction(trans, root);
2621
2622 return 0;
2623 }
2624
2625 static void get_block_group_info(struct list_head *groups_list,
2626 struct btrfs_ioctl_space_info *space)
2627 {
2628 struct btrfs_block_group_cache *block_group;
2629
2630 space->total_bytes = 0;
2631 space->used_bytes = 0;
2632 space->flags = 0;
2633 list_for_each_entry(block_group, groups_list, list) {
2634 space->flags = block_group->flags;
2635 space->total_bytes += block_group->key.offset;
2636 space->used_bytes +=
2637 btrfs_block_group_used(&block_group->item);
2638 }
2639 }
2640
2641 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
2642 {
2643 struct btrfs_ioctl_space_args space_args;
2644 struct btrfs_ioctl_space_info space;
2645 struct btrfs_ioctl_space_info *dest;
2646 struct btrfs_ioctl_space_info *dest_orig;
2647 struct btrfs_ioctl_space_info __user *user_dest;
2648 struct btrfs_space_info *info;
2649 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2650 BTRFS_BLOCK_GROUP_SYSTEM,
2651 BTRFS_BLOCK_GROUP_METADATA,
2652 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
2653 int num_types = 4;
2654 int alloc_size;
2655 int ret = 0;
2656 u64 slot_count = 0;
2657 int i, c;
2658
2659 if (copy_from_user(&space_args,
2660 (struct btrfs_ioctl_space_args __user *)arg,
2661 sizeof(space_args)))
2662 return -EFAULT;
2663
2664 for (i = 0; i < num_types; i++) {
2665 struct btrfs_space_info *tmp;
2666
2667 info = NULL;
2668 rcu_read_lock();
2669 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2670 list) {
2671 if (tmp->flags == types[i]) {
2672 info = tmp;
2673 break;
2674 }
2675 }
2676 rcu_read_unlock();
2677
2678 if (!info)
2679 continue;
2680
2681 down_read(&info->groups_sem);
2682 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2683 if (!list_empty(&info->block_groups[c]))
2684 slot_count++;
2685 }
2686 up_read(&info->groups_sem);
2687 }
2688
2689 /* space_slots == 0 means they are asking for a count */
2690 if (space_args.space_slots == 0) {
2691 space_args.total_spaces = slot_count;
2692 goto out;
2693 }
2694
2695 slot_count = min_t(u64, space_args.space_slots, slot_count);
2696
2697 alloc_size = sizeof(*dest) * slot_count;
2698
2699 /* we generally have at most 6 or so space infos, one for each raid
2700 * level. So, a whole page should be more than enough for everyone
2701 */
2702 if (alloc_size > PAGE_CACHE_SIZE)
2703 return -ENOMEM;
2704
2705 space_args.total_spaces = 0;
2706 dest = kmalloc(alloc_size, GFP_NOFS);
2707 if (!dest)
2708 return -ENOMEM;
2709 dest_orig = dest;
2710
2711 /* now we have a buffer to copy into */
2712 for (i = 0; i < num_types; i++) {
2713 struct btrfs_space_info *tmp;
2714
2715 if (!slot_count)
2716 break;
2717
2718 info = NULL;
2719 rcu_read_lock();
2720 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2721 list) {
2722 if (tmp->flags == types[i]) {
2723 info = tmp;
2724 break;
2725 }
2726 }
2727 rcu_read_unlock();
2728
2729 if (!info)
2730 continue;
2731 down_read(&info->groups_sem);
2732 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2733 if (!list_empty(&info->block_groups[c])) {
2734 get_block_group_info(&info->block_groups[c],
2735 &space);
2736 memcpy(dest, &space, sizeof(space));
2737 dest++;
2738 space_args.total_spaces++;
2739 slot_count--;
2740 }
2741 if (!slot_count)
2742 break;
2743 }
2744 up_read(&info->groups_sem);
2745 }
2746
2747 user_dest = (struct btrfs_ioctl_space_info *)
2748 (arg + sizeof(struct btrfs_ioctl_space_args));
2749
2750 if (copy_to_user(user_dest, dest_orig, alloc_size))
2751 ret = -EFAULT;
2752
2753 kfree(dest_orig);
2754 out:
2755 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
2756 ret = -EFAULT;
2757
2758 return ret;
2759 }
2760
2761 /*
2762 * there are many ways the trans_start and trans_end ioctls can lead
2763 * to deadlocks. They should only be used by applications that
2764 * basically own the machine, and have a very in depth understanding
2765 * of all the possible deadlocks and enospc problems.
2766 */
2767 long btrfs_ioctl_trans_end(struct file *file)
2768 {
2769 struct inode *inode = fdentry(file)->d_inode;
2770 struct btrfs_root *root = BTRFS_I(inode)->root;
2771 struct btrfs_trans_handle *trans;
2772
2773 trans = file->private_data;
2774 if (!trans)
2775 return -EINVAL;
2776 file->private_data = NULL;
2777
2778 btrfs_end_transaction(trans, root);
2779
2780 atomic_dec(&root->fs_info->open_ioctl_trans);
2781
2782 mnt_drop_write(file->f_path.mnt);
2783 return 0;
2784 }
2785
2786 static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
2787 {
2788 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2789 struct btrfs_trans_handle *trans;
2790 u64 transid;
2791 int ret;
2792
2793 trans = btrfs_start_transaction(root, 0);
2794 if (IS_ERR(trans))
2795 return PTR_ERR(trans);
2796 transid = trans->transid;
2797 ret = btrfs_commit_transaction_async(trans, root, 0);
2798 if (ret) {
2799 btrfs_end_transaction(trans, root);
2800 return ret;
2801 }
2802
2803 if (argp)
2804 if (copy_to_user(argp, &transid, sizeof(transid)))
2805 return -EFAULT;
2806 return 0;
2807 }
2808
2809 static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
2810 {
2811 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2812 u64 transid;
2813
2814 if (argp) {
2815 if (copy_from_user(&transid, argp, sizeof(transid)))
2816 return -EFAULT;
2817 } else {
2818 transid = 0; /* current trans */
2819 }
2820 return btrfs_wait_for_commit(root, transid);
2821 }
2822
2823 static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg)
2824 {
2825 int ret;
2826 struct btrfs_ioctl_scrub_args *sa;
2827
2828 if (!capable(CAP_SYS_ADMIN))
2829 return -EPERM;
2830
2831 sa = memdup_user(arg, sizeof(*sa));
2832 if (IS_ERR(sa))
2833 return PTR_ERR(sa);
2834
2835 ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end,
2836 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY);
2837
2838 if (copy_to_user(arg, sa, sizeof(*sa)))
2839 ret = -EFAULT;
2840
2841 kfree(sa);
2842 return ret;
2843 }
2844
2845 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
2846 {
2847 if (!capable(CAP_SYS_ADMIN))
2848 return -EPERM;
2849
2850 return btrfs_scrub_cancel(root);
2851 }
2852
2853 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
2854 void __user *arg)
2855 {
2856 struct btrfs_ioctl_scrub_args *sa;
2857 int ret;
2858
2859 if (!capable(CAP_SYS_ADMIN))
2860 return -EPERM;
2861
2862 sa = memdup_user(arg, sizeof(*sa));
2863 if (IS_ERR(sa))
2864 return PTR_ERR(sa);
2865
2866 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
2867
2868 if (copy_to_user(arg, sa, sizeof(*sa)))
2869 ret = -EFAULT;
2870
2871 kfree(sa);
2872 return ret;
2873 }
2874
2875 long btrfs_ioctl(struct file *file, unsigned int
2876 cmd, unsigned long arg)
2877 {
2878 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2879 void __user *argp = (void __user *)arg;
2880
2881 switch (cmd) {
2882 case FS_IOC_GETFLAGS:
2883 return btrfs_ioctl_getflags(file, argp);
2884 case FS_IOC_SETFLAGS:
2885 return btrfs_ioctl_setflags(file, argp);
2886 case FS_IOC_GETVERSION:
2887 return btrfs_ioctl_getversion(file, argp);
2888 case FITRIM:
2889 return btrfs_ioctl_fitrim(file, argp);
2890 case BTRFS_IOC_SNAP_CREATE:
2891 return btrfs_ioctl_snap_create(file, argp, 0);
2892 case BTRFS_IOC_SNAP_CREATE_V2:
2893 return btrfs_ioctl_snap_create_v2(file, argp, 0);
2894 case BTRFS_IOC_SUBVOL_CREATE:
2895 return btrfs_ioctl_snap_create(file, argp, 1);
2896 case BTRFS_IOC_SNAP_DESTROY:
2897 return btrfs_ioctl_snap_destroy(file, argp);
2898 case BTRFS_IOC_SUBVOL_GETFLAGS:
2899 return btrfs_ioctl_subvol_getflags(file, argp);
2900 case BTRFS_IOC_SUBVOL_SETFLAGS:
2901 return btrfs_ioctl_subvol_setflags(file, argp);
2902 case BTRFS_IOC_DEFAULT_SUBVOL:
2903 return btrfs_ioctl_default_subvol(file, argp);
2904 case BTRFS_IOC_DEFRAG:
2905 return btrfs_ioctl_defrag(file, NULL);
2906 case BTRFS_IOC_DEFRAG_RANGE:
2907 return btrfs_ioctl_defrag(file, argp);
2908 case BTRFS_IOC_RESIZE:
2909 return btrfs_ioctl_resize(root, argp);
2910 case BTRFS_IOC_ADD_DEV:
2911 return btrfs_ioctl_add_dev(root, argp);
2912 case BTRFS_IOC_RM_DEV:
2913 return btrfs_ioctl_rm_dev(root, argp);
2914 case BTRFS_IOC_FS_INFO:
2915 return btrfs_ioctl_fs_info(root, argp);
2916 case BTRFS_IOC_DEV_INFO:
2917 return btrfs_ioctl_dev_info(root, argp);
2918 case BTRFS_IOC_BALANCE:
2919 return btrfs_balance(root->fs_info->dev_root);
2920 case BTRFS_IOC_CLONE:
2921 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
2922 case BTRFS_IOC_CLONE_RANGE:
2923 return btrfs_ioctl_clone_range(file, argp);
2924 case BTRFS_IOC_TRANS_START:
2925 return btrfs_ioctl_trans_start(file);
2926 case BTRFS_IOC_TRANS_END:
2927 return btrfs_ioctl_trans_end(file);
2928 case BTRFS_IOC_TREE_SEARCH:
2929 return btrfs_ioctl_tree_search(file, argp);
2930 case BTRFS_IOC_INO_LOOKUP:
2931 return btrfs_ioctl_ino_lookup(file, argp);
2932 case BTRFS_IOC_SPACE_INFO:
2933 return btrfs_ioctl_space_info(root, argp);
2934 case BTRFS_IOC_SYNC:
2935 btrfs_sync_fs(file->f_dentry->d_sb, 1);
2936 return 0;
2937 case BTRFS_IOC_START_SYNC:
2938 return btrfs_ioctl_start_sync(file, argp);
2939 case BTRFS_IOC_WAIT_SYNC:
2940 return btrfs_ioctl_wait_sync(file, argp);
2941 case BTRFS_IOC_SCRUB:
2942 return btrfs_ioctl_scrub(root, argp);
2943 case BTRFS_IOC_SCRUB_CANCEL:
2944 return btrfs_ioctl_scrub_cancel(root, argp);
2945 case BTRFS_IOC_SCRUB_PROGRESS:
2946 return btrfs_ioctl_scrub_progress(root, argp);
2947 }
2948
2949 return -ENOTTY;
2950 }
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree