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btrfs: separate superblock items out of fs_info
[deliverable/linux.git] / fs / btrfs / ioctl.c
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19 #include <linux/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.h>
23 #include <linux/fs.h>
24 #include <linux/fsnotify.h>
25 #include <linux/pagemap.h>
26 #include <linux/highmem.h>
27 #include <linux/time.h>
28 #include <linux/init.h>
29 #include <linux/string.h>
30 #include <linux/backing-dev.h>
31 #include <linux/mount.h>
32 #include <linux/mpage.h>
33 #include <linux/namei.h>
34 #include <linux/swap.h>
35 #include <linux/writeback.h>
36 #include <linux/statfs.h>
37 #include <linux/compat.h>
38 #include <linux/bit_spinlock.h>
39 #include <linux/security.h>
40 #include <linux/xattr.h>
41 #include <linux/vmalloc.h>
42 #include <linux/slab.h>
43 #include <linux/blkdev.h>
44 #include "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 * Currently only the compression flags and the cow flags are inherited.
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 (flags & BTRFS_INODE_NOCOMPRESS) {
132 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
133 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
134 } else if (flags & BTRFS_INODE_COMPRESS) {
135 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
136 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
137 }
138
139 if (flags & BTRFS_INODE_NODATACOW)
140 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
141
142 btrfs_update_iflags(inode);
143 }
144
145 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
146 {
147 struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
148 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
149
150 if (copy_to_user(arg, &flags, sizeof(flags)))
151 return -EFAULT;
152 return 0;
153 }
154
155 static int check_flags(unsigned int flags)
156 {
157 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
158 FS_NOATIME_FL | FS_NODUMP_FL | \
159 FS_SYNC_FL | FS_DIRSYNC_FL | \
160 FS_NOCOMP_FL | FS_COMPR_FL |
161 FS_NOCOW_FL))
162 return -EOPNOTSUPP;
163
164 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
165 return -EINVAL;
166
167 return 0;
168 }
169
170 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
171 {
172 struct inode *inode = file->f_path.dentry->d_inode;
173 struct btrfs_inode *ip = BTRFS_I(inode);
174 struct btrfs_root *root = ip->root;
175 struct btrfs_trans_handle *trans;
176 unsigned int flags, oldflags;
177 int ret;
178
179 if (btrfs_root_readonly(root))
180 return -EROFS;
181
182 if (copy_from_user(&flags, arg, sizeof(flags)))
183 return -EFAULT;
184
185 ret = check_flags(flags);
186 if (ret)
187 return ret;
188
189 if (!inode_owner_or_capable(inode))
190 return -EACCES;
191
192 mutex_lock(&inode->i_mutex);
193
194 flags = btrfs_mask_flags(inode->i_mode, flags);
195 oldflags = btrfs_flags_to_ioctl(ip->flags);
196 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
197 if (!capable(CAP_LINUX_IMMUTABLE)) {
198 ret = -EPERM;
199 goto out_unlock;
200 }
201 }
202
203 ret = mnt_want_write(file->f_path.mnt);
204 if (ret)
205 goto out_unlock;
206
207 if (flags & FS_SYNC_FL)
208 ip->flags |= BTRFS_INODE_SYNC;
209 else
210 ip->flags &= ~BTRFS_INODE_SYNC;
211 if (flags & FS_IMMUTABLE_FL)
212 ip->flags |= BTRFS_INODE_IMMUTABLE;
213 else
214 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
215 if (flags & FS_APPEND_FL)
216 ip->flags |= BTRFS_INODE_APPEND;
217 else
218 ip->flags &= ~BTRFS_INODE_APPEND;
219 if (flags & FS_NODUMP_FL)
220 ip->flags |= BTRFS_INODE_NODUMP;
221 else
222 ip->flags &= ~BTRFS_INODE_NODUMP;
223 if (flags & FS_NOATIME_FL)
224 ip->flags |= BTRFS_INODE_NOATIME;
225 else
226 ip->flags &= ~BTRFS_INODE_NOATIME;
227 if (flags & FS_DIRSYNC_FL)
228 ip->flags |= BTRFS_INODE_DIRSYNC;
229 else
230 ip->flags &= ~BTRFS_INODE_DIRSYNC;
231 if (flags & FS_NOCOW_FL)
232 ip->flags |= BTRFS_INODE_NODATACOW;
233 else
234 ip->flags &= ~BTRFS_INODE_NODATACOW;
235
236 /*
237 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
238 * flag may be changed automatically if compression code won't make
239 * things smaller.
240 */
241 if (flags & FS_NOCOMP_FL) {
242 ip->flags &= ~BTRFS_INODE_COMPRESS;
243 ip->flags |= BTRFS_INODE_NOCOMPRESS;
244 } else if (flags & FS_COMPR_FL) {
245 ip->flags |= BTRFS_INODE_COMPRESS;
246 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
247 } else {
248 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
249 }
250
251 trans = btrfs_join_transaction(root);
252 BUG_ON(IS_ERR(trans));
253
254 ret = btrfs_update_inode(trans, root, inode);
255 BUG_ON(ret);
256
257 btrfs_update_iflags(inode);
258 inode->i_ctime = CURRENT_TIME;
259 btrfs_end_transaction(trans, root);
260
261 mnt_drop_write(file->f_path.mnt);
262
263 ret = 0;
264 out_unlock:
265 mutex_unlock(&inode->i_mutex);
266 return ret;
267 }
268
269 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
270 {
271 struct inode *inode = file->f_path.dentry->d_inode;
272
273 return put_user(inode->i_generation, arg);
274 }
275
276 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
277 {
278 struct btrfs_root *root = fdentry(file)->d_sb->s_fs_info;
279 struct btrfs_fs_info *fs_info = root->fs_info;
280 struct btrfs_device *device;
281 struct request_queue *q;
282 struct fstrim_range range;
283 u64 minlen = ULLONG_MAX;
284 u64 num_devices = 0;
285 u64 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy);
286 int ret;
287
288 if (!capable(CAP_SYS_ADMIN))
289 return -EPERM;
290
291 rcu_read_lock();
292 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
293 dev_list) {
294 if (!device->bdev)
295 continue;
296 q = bdev_get_queue(device->bdev);
297 if (blk_queue_discard(q)) {
298 num_devices++;
299 minlen = min((u64)q->limits.discard_granularity,
300 minlen);
301 }
302 }
303 rcu_read_unlock();
304
305 if (!num_devices)
306 return -EOPNOTSUPP;
307 if (copy_from_user(&range, arg, sizeof(range)))
308 return -EFAULT;
309 if (range.start > total_bytes)
310 return -EINVAL;
311
312 range.len = min(range.len, total_bytes - range.start);
313 range.minlen = max(range.minlen, minlen);
314 ret = btrfs_trim_fs(root, &range);
315 if (ret < 0)
316 return ret;
317
318 if (copy_to_user(arg, &range, sizeof(range)))
319 return -EFAULT;
320
321 return 0;
322 }
323
324 static noinline int create_subvol(struct btrfs_root *root,
325 struct dentry *dentry,
326 char *name, int namelen,
327 u64 *async_transid)
328 {
329 struct btrfs_trans_handle *trans;
330 struct btrfs_key key;
331 struct btrfs_root_item root_item;
332 struct btrfs_inode_item *inode_item;
333 struct extent_buffer *leaf;
334 struct btrfs_root *new_root;
335 struct dentry *parent = dentry->d_parent;
336 struct inode *dir;
337 int ret;
338 int err;
339 u64 objectid;
340 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
341 u64 index = 0;
342
343 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
344 if (ret)
345 return ret;
346
347 dir = parent->d_inode;
348
349 /*
350 * 1 - inode item
351 * 2 - refs
352 * 1 - root item
353 * 2 - dir items
354 */
355 trans = btrfs_start_transaction(root, 6);
356 if (IS_ERR(trans))
357 return PTR_ERR(trans);
358
359 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
360 0, objectid, NULL, 0, 0, 0);
361 if (IS_ERR(leaf)) {
362 ret = PTR_ERR(leaf);
363 goto fail;
364 }
365
366 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
367 btrfs_set_header_bytenr(leaf, leaf->start);
368 btrfs_set_header_generation(leaf, trans->transid);
369 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
370 btrfs_set_header_owner(leaf, objectid);
371
372 write_extent_buffer(leaf, root->fs_info->fsid,
373 (unsigned long)btrfs_header_fsid(leaf),
374 BTRFS_FSID_SIZE);
375 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
376 (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
377 BTRFS_UUID_SIZE);
378 btrfs_mark_buffer_dirty(leaf);
379
380 inode_item = &root_item.inode;
381 memset(inode_item, 0, sizeof(*inode_item));
382 inode_item->generation = cpu_to_le64(1);
383 inode_item->size = cpu_to_le64(3);
384 inode_item->nlink = cpu_to_le32(1);
385 inode_item->nbytes = cpu_to_le64(root->leafsize);
386 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
387
388 root_item.flags = 0;
389 root_item.byte_limit = 0;
390 inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
391
392 btrfs_set_root_bytenr(&root_item, leaf->start);
393 btrfs_set_root_generation(&root_item, trans->transid);
394 btrfs_set_root_level(&root_item, 0);
395 btrfs_set_root_refs(&root_item, 1);
396 btrfs_set_root_used(&root_item, leaf->len);
397 btrfs_set_root_last_snapshot(&root_item, 0);
398
399 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
400 root_item.drop_level = 0;
401
402 btrfs_tree_unlock(leaf);
403 free_extent_buffer(leaf);
404 leaf = NULL;
405
406 btrfs_set_root_dirid(&root_item, new_dirid);
407
408 key.objectid = objectid;
409 key.offset = 0;
410 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
411 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
412 &root_item);
413 if (ret)
414 goto fail;
415
416 key.offset = (u64)-1;
417 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
418 BUG_ON(IS_ERR(new_root));
419
420 btrfs_record_root_in_trans(trans, new_root);
421
422 ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
423 /*
424 * insert the directory item
425 */
426 ret = btrfs_set_inode_index(dir, &index);
427 BUG_ON(ret);
428
429 ret = btrfs_insert_dir_item(trans, root,
430 name, namelen, dir, &key,
431 BTRFS_FT_DIR, index);
432 if (ret)
433 goto fail;
434
435 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
436 ret = btrfs_update_inode(trans, root, dir);
437 BUG_ON(ret);
438
439 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
440 objectid, root->root_key.objectid,
441 btrfs_ino(dir), index, name, namelen);
442
443 BUG_ON(ret);
444
445 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
446 fail:
447 if (async_transid) {
448 *async_transid = trans->transid;
449 err = btrfs_commit_transaction_async(trans, root, 1);
450 } else {
451 err = btrfs_commit_transaction(trans, root);
452 }
453 if (err && !ret)
454 ret = err;
455 return ret;
456 }
457
458 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
459 char *name, int namelen, u64 *async_transid,
460 bool readonly)
461 {
462 struct inode *inode;
463 struct btrfs_pending_snapshot *pending_snapshot;
464 struct btrfs_trans_handle *trans;
465 int ret;
466
467 if (!root->ref_cows)
468 return -EINVAL;
469
470 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
471 if (!pending_snapshot)
472 return -ENOMEM;
473
474 btrfs_init_block_rsv(&pending_snapshot->block_rsv);
475 pending_snapshot->dentry = dentry;
476 pending_snapshot->root = root;
477 pending_snapshot->readonly = readonly;
478
479 trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
480 if (IS_ERR(trans)) {
481 ret = PTR_ERR(trans);
482 goto fail;
483 }
484
485 ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
486 BUG_ON(ret);
487
488 spin_lock(&root->fs_info->trans_lock);
489 list_add(&pending_snapshot->list,
490 &trans->transaction->pending_snapshots);
491 spin_unlock(&root->fs_info->trans_lock);
492 if (async_transid) {
493 *async_transid = trans->transid;
494 ret = btrfs_commit_transaction_async(trans,
495 root->fs_info->extent_root, 1);
496 } else {
497 ret = btrfs_commit_transaction(trans,
498 root->fs_info->extent_root);
499 }
500 BUG_ON(ret);
501
502 ret = pending_snapshot->error;
503 if (ret)
504 goto fail;
505
506 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
507 if (ret)
508 goto fail;
509
510 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
511 if (IS_ERR(inode)) {
512 ret = PTR_ERR(inode);
513 goto fail;
514 }
515 BUG_ON(!inode);
516 d_instantiate(dentry, inode);
517 ret = 0;
518 fail:
519 kfree(pending_snapshot);
520 return ret;
521 }
522
523 /* copy of check_sticky in fs/namei.c()
524 * It's inline, so penalty for filesystems that don't use sticky bit is
525 * minimal.
526 */
527 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
528 {
529 uid_t fsuid = current_fsuid();
530
531 if (!(dir->i_mode & S_ISVTX))
532 return 0;
533 if (inode->i_uid == fsuid)
534 return 0;
535 if (dir->i_uid == fsuid)
536 return 0;
537 return !capable(CAP_FOWNER);
538 }
539
540 /* copy of may_delete in fs/namei.c()
541 * Check whether we can remove a link victim from directory dir, check
542 * whether the type of victim is right.
543 * 1. We can't do it if dir is read-only (done in permission())
544 * 2. We should have write and exec permissions on dir
545 * 3. We can't remove anything from append-only dir
546 * 4. We can't do anything with immutable dir (done in permission())
547 * 5. If the sticky bit on dir is set we should either
548 * a. be owner of dir, or
549 * b. be owner of victim, or
550 * c. have CAP_FOWNER capability
551 * 6. If the victim is append-only or immutable we can't do antyhing with
552 * links pointing to it.
553 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
554 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
555 * 9. We can't remove a root or mountpoint.
556 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
557 * nfs_async_unlink().
558 */
559
560 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
561 {
562 int error;
563
564 if (!victim->d_inode)
565 return -ENOENT;
566
567 BUG_ON(victim->d_parent->d_inode != dir);
568 audit_inode_child(victim, dir);
569
570 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
571 if (error)
572 return error;
573 if (IS_APPEND(dir))
574 return -EPERM;
575 if (btrfs_check_sticky(dir, victim->d_inode)||
576 IS_APPEND(victim->d_inode)||
577 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
578 return -EPERM;
579 if (isdir) {
580 if (!S_ISDIR(victim->d_inode->i_mode))
581 return -ENOTDIR;
582 if (IS_ROOT(victim))
583 return -EBUSY;
584 } else if (S_ISDIR(victim->d_inode->i_mode))
585 return -EISDIR;
586 if (IS_DEADDIR(dir))
587 return -ENOENT;
588 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
589 return -EBUSY;
590 return 0;
591 }
592
593 /* copy of may_create in fs/namei.c() */
594 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
595 {
596 if (child->d_inode)
597 return -EEXIST;
598 if (IS_DEADDIR(dir))
599 return -ENOENT;
600 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
601 }
602
603 /*
604 * Create a new subvolume below @parent. This is largely modeled after
605 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
606 * inside this filesystem so it's quite a bit simpler.
607 */
608 static noinline int btrfs_mksubvol(struct path *parent,
609 char *name, int namelen,
610 struct btrfs_root *snap_src,
611 u64 *async_transid, bool readonly)
612 {
613 struct inode *dir = parent->dentry->d_inode;
614 struct dentry *dentry;
615 int error;
616
617 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
618
619 dentry = lookup_one_len(name, parent->dentry, namelen);
620 error = PTR_ERR(dentry);
621 if (IS_ERR(dentry))
622 goto out_unlock;
623
624 error = -EEXIST;
625 if (dentry->d_inode)
626 goto out_dput;
627
628 error = mnt_want_write(parent->mnt);
629 if (error)
630 goto out_dput;
631
632 error = btrfs_may_create(dir, dentry);
633 if (error)
634 goto out_drop_write;
635
636 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
637
638 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
639 goto out_up_read;
640
641 if (snap_src) {
642 error = create_snapshot(snap_src, dentry,
643 name, namelen, async_transid, readonly);
644 } else {
645 error = create_subvol(BTRFS_I(dir)->root, dentry,
646 name, namelen, async_transid);
647 }
648 if (!error)
649 fsnotify_mkdir(dir, dentry);
650 out_up_read:
651 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
652 out_drop_write:
653 mnt_drop_write(parent->mnt);
654 out_dput:
655 dput(dentry);
656 out_unlock:
657 mutex_unlock(&dir->i_mutex);
658 return error;
659 }
660
661 /*
662 * When we're defragging a range, we don't want to kick it off again
663 * if it is really just waiting for delalloc to send it down.
664 * If we find a nice big extent or delalloc range for the bytes in the
665 * file you want to defrag, we return 0 to let you know to skip this
666 * part of the file
667 */
668 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
669 {
670 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
671 struct extent_map *em = NULL;
672 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
673 u64 end;
674
675 read_lock(&em_tree->lock);
676 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
677 read_unlock(&em_tree->lock);
678
679 if (em) {
680 end = extent_map_end(em);
681 free_extent_map(em);
682 if (end - offset > thresh)
683 return 0;
684 }
685 /* if we already have a nice delalloc here, just stop */
686 thresh /= 2;
687 end = count_range_bits(io_tree, &offset, offset + thresh,
688 thresh, EXTENT_DELALLOC, 1);
689 if (end >= thresh)
690 return 0;
691 return 1;
692 }
693
694 /*
695 * helper function to walk through a file and find extents
696 * newer than a specific transid, and smaller than thresh.
697 *
698 * This is used by the defragging code to find new and small
699 * extents
700 */
701 static int find_new_extents(struct btrfs_root *root,
702 struct inode *inode, u64 newer_than,
703 u64 *off, int thresh)
704 {
705 struct btrfs_path *path;
706 struct btrfs_key min_key;
707 struct btrfs_key max_key;
708 struct extent_buffer *leaf;
709 struct btrfs_file_extent_item *extent;
710 int type;
711 int ret;
712 u64 ino = btrfs_ino(inode);
713
714 path = btrfs_alloc_path();
715 if (!path)
716 return -ENOMEM;
717
718 min_key.objectid = ino;
719 min_key.type = BTRFS_EXTENT_DATA_KEY;
720 min_key.offset = *off;
721
722 max_key.objectid = ino;
723 max_key.type = (u8)-1;
724 max_key.offset = (u64)-1;
725
726 path->keep_locks = 1;
727
728 while(1) {
729 ret = btrfs_search_forward(root, &min_key, &max_key,
730 path, 0, newer_than);
731 if (ret != 0)
732 goto none;
733 if (min_key.objectid != ino)
734 goto none;
735 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
736 goto none;
737
738 leaf = path->nodes[0];
739 extent = btrfs_item_ptr(leaf, path->slots[0],
740 struct btrfs_file_extent_item);
741
742 type = btrfs_file_extent_type(leaf, extent);
743 if (type == BTRFS_FILE_EXTENT_REG &&
744 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
745 check_defrag_in_cache(inode, min_key.offset, thresh)) {
746 *off = min_key.offset;
747 btrfs_free_path(path);
748 return 0;
749 }
750
751 if (min_key.offset == (u64)-1)
752 goto none;
753
754 min_key.offset++;
755 btrfs_release_path(path);
756 }
757 none:
758 btrfs_free_path(path);
759 return -ENOENT;
760 }
761
762 static int should_defrag_range(struct inode *inode, u64 start, u64 len,
763 int thresh, u64 *last_len, u64 *skip,
764 u64 *defrag_end)
765 {
766 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
767 struct extent_map *em = NULL;
768 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
769 int ret = 1;
770
771 /*
772 * make sure that once we start defragging an extent, we keep on
773 * defragging it
774 */
775 if (start < *defrag_end)
776 return 1;
777
778 *skip = 0;
779
780 /*
781 * hopefully we have this extent in the tree already, try without
782 * the full extent lock
783 */
784 read_lock(&em_tree->lock);
785 em = lookup_extent_mapping(em_tree, start, len);
786 read_unlock(&em_tree->lock);
787
788 if (!em) {
789 /* get the big lock and read metadata off disk */
790 lock_extent(io_tree, start, start + len - 1, GFP_NOFS);
791 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
792 unlock_extent(io_tree, start, start + len - 1, GFP_NOFS);
793
794 if (IS_ERR(em))
795 return 0;
796 }
797
798 /* this will cover holes, and inline extents */
799 if (em->block_start >= EXTENT_MAP_LAST_BYTE)
800 ret = 0;
801
802 /*
803 * we hit a real extent, if it is big don't bother defragging it again
804 */
805 if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
806 ret = 0;
807
808 /*
809 * last_len ends up being a counter of how many bytes we've defragged.
810 * every time we choose not to defrag an extent, we reset *last_len
811 * so that the next tiny extent will force a defrag.
812 *
813 * The end result of this is that tiny extents before a single big
814 * extent will force at least part of that big extent to be defragged.
815 */
816 if (ret) {
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 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
855
856 if (isize == 0)
857 return 0;
858 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
859
860 ret = btrfs_delalloc_reserve_space(inode,
861 num_pages << PAGE_CACHE_SHIFT);
862 if (ret)
863 return ret;
864 again:
865 ret = 0;
866 i_done = 0;
867
868 /* step one, lock all the pages */
869 for (i = 0; i < num_pages; i++) {
870 struct page *page;
871 page = find_or_create_page(inode->i_mapping,
872 start_index + i, mask);
873 if (!page)
874 break;
875
876 if (!PageUptodate(page)) {
877 btrfs_readpage(NULL, page);
878 lock_page(page);
879 if (!PageUptodate(page)) {
880 unlock_page(page);
881 page_cache_release(page);
882 ret = -EIO;
883 break;
884 }
885 }
886 isize = i_size_read(inode);
887 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
888 if (!isize || page->index > file_end ||
889 page->mapping != inode->i_mapping) {
890 /* whoops, we blew past eof, skip this page */
891 unlock_page(page);
892 page_cache_release(page);
893 break;
894 }
895 pages[i] = page;
896 i_done++;
897 }
898 if (!i_done || ret)
899 goto out;
900
901 if (!(inode->i_sb->s_flags & MS_ACTIVE))
902 goto out;
903
904 /*
905 * so now we have a nice long stream of locked
906 * and up to date pages, lets wait on them
907 */
908 for (i = 0; i < i_done; i++)
909 wait_on_page_writeback(pages[i]);
910
911 page_start = page_offset(pages[0]);
912 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
913
914 lock_extent_bits(&BTRFS_I(inode)->io_tree,
915 page_start, page_end - 1, 0, &cached_state,
916 GFP_NOFS);
917 ordered = btrfs_lookup_first_ordered_extent(inode, page_end - 1);
918 if (ordered &&
919 ordered->file_offset + ordered->len > page_start &&
920 ordered->file_offset < page_end) {
921 btrfs_put_ordered_extent(ordered);
922 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
923 page_start, page_end - 1,
924 &cached_state, GFP_NOFS);
925 for (i = 0; i < i_done; i++) {
926 unlock_page(pages[i]);
927 page_cache_release(pages[i]);
928 }
929 btrfs_wait_ordered_range(inode, page_start,
930 page_end - page_start);
931 goto again;
932 }
933 if (ordered)
934 btrfs_put_ordered_extent(ordered);
935
936 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
937 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
938 EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
939 GFP_NOFS);
940
941 if (i_done != num_pages) {
942 spin_lock(&BTRFS_I(inode)->lock);
943 BTRFS_I(inode)->outstanding_extents++;
944 spin_unlock(&BTRFS_I(inode)->lock);
945 btrfs_delalloc_release_space(inode,
946 (num_pages - i_done) << PAGE_CACHE_SHIFT);
947 }
948
949
950 btrfs_set_extent_delalloc(inode, page_start, page_end - 1,
951 &cached_state);
952
953 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
954 page_start, page_end - 1, &cached_state,
955 GFP_NOFS);
956
957 for (i = 0; i < i_done; i++) {
958 clear_page_dirty_for_io(pages[i]);
959 ClearPageChecked(pages[i]);
960 set_page_extent_mapped(pages[i]);
961 set_page_dirty(pages[i]);
962 unlock_page(pages[i]);
963 page_cache_release(pages[i]);
964 }
965 return i_done;
966 out:
967 for (i = 0; i < i_done; i++) {
968 unlock_page(pages[i]);
969 page_cache_release(pages[i]);
970 }
971 btrfs_delalloc_release_space(inode, num_pages << PAGE_CACHE_SHIFT);
972 return ret;
973
974 }
975
976 int btrfs_defrag_file(struct inode *inode, struct file *file,
977 struct btrfs_ioctl_defrag_range_args *range,
978 u64 newer_than, unsigned long max_to_defrag)
979 {
980 struct btrfs_root *root = BTRFS_I(inode)->root;
981 struct btrfs_super_block *disk_super;
982 struct file_ra_state *ra = NULL;
983 unsigned long last_index;
984 u64 isize = i_size_read(inode);
985 u64 features;
986 u64 last_len = 0;
987 u64 skip = 0;
988 u64 defrag_end = 0;
989 u64 newer_off = range->start;
990 unsigned long i;
991 unsigned long ra_index = 0;
992 int ret;
993 int defrag_count = 0;
994 int compress_type = BTRFS_COMPRESS_ZLIB;
995 int extent_thresh = range->extent_thresh;
996 int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
997 int cluster = max_cluster;
998 u64 new_align = ~((u64)128 * 1024 - 1);
999 struct page **pages = NULL;
1000
1001 if (extent_thresh == 0)
1002 extent_thresh = 256 * 1024;
1003
1004 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1005 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1006 return -EINVAL;
1007 if (range->compress_type)
1008 compress_type = range->compress_type;
1009 }
1010
1011 if (isize == 0)
1012 return 0;
1013
1014 /*
1015 * if we were not given a file, allocate a readahead
1016 * context
1017 */
1018 if (!file) {
1019 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1020 if (!ra)
1021 return -ENOMEM;
1022 file_ra_state_init(ra, inode->i_mapping);
1023 } else {
1024 ra = &file->f_ra;
1025 }
1026
1027 pages = kmalloc(sizeof(struct page *) * max_cluster,
1028 GFP_NOFS);
1029 if (!pages) {
1030 ret = -ENOMEM;
1031 goto out_ra;
1032 }
1033
1034 /* find the last page to defrag */
1035 if (range->start + range->len > range->start) {
1036 last_index = min_t(u64, isize - 1,
1037 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1038 } else {
1039 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1040 }
1041
1042 if (newer_than) {
1043 ret = find_new_extents(root, inode, newer_than,
1044 &newer_off, 64 * 1024);
1045 if (!ret) {
1046 range->start = newer_off;
1047 /*
1048 * we always align our defrag to help keep
1049 * the extents in the file evenly spaced
1050 */
1051 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1052 } else
1053 goto out_ra;
1054 } else {
1055 i = range->start >> PAGE_CACHE_SHIFT;
1056 }
1057 if (!max_to_defrag)
1058 max_to_defrag = last_index;
1059
1060 /*
1061 * make writeback starts from i, so the defrag range can be
1062 * written sequentially.
1063 */
1064 if (i < inode->i_mapping->writeback_index)
1065 inode->i_mapping->writeback_index = i;
1066
1067 while (i <= last_index && defrag_count < max_to_defrag &&
1068 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1069 PAGE_CACHE_SHIFT)) {
1070 /*
1071 * make sure we stop running if someone unmounts
1072 * the FS
1073 */
1074 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1075 break;
1076
1077 if (!newer_than &&
1078 !should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1079 PAGE_CACHE_SIZE,
1080 extent_thresh,
1081 &last_len, &skip,
1082 &defrag_end)) {
1083 unsigned long next;
1084 /*
1085 * the should_defrag function tells us how much to skip
1086 * bump our counter by the suggested amount
1087 */
1088 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1089 i = max(i + 1, next);
1090 continue;
1091 }
1092
1093 if (!newer_than) {
1094 cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1095 PAGE_CACHE_SHIFT) - i;
1096 cluster = min(cluster, max_cluster);
1097 } else {
1098 cluster = max_cluster;
1099 }
1100
1101 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1102 BTRFS_I(inode)->force_compress = compress_type;
1103
1104 if (i + cluster > ra_index) {
1105 ra_index = max(i, ra_index);
1106 btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1107 cluster);
1108 ra_index += max_cluster;
1109 }
1110
1111 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1112 if (ret < 0)
1113 goto out_ra;
1114
1115 defrag_count += ret;
1116 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
1117
1118 if (newer_than) {
1119 if (newer_off == (u64)-1)
1120 break;
1121
1122 newer_off = max(newer_off + 1,
1123 (u64)i << PAGE_CACHE_SHIFT);
1124
1125 ret = find_new_extents(root, inode,
1126 newer_than, &newer_off,
1127 64 * 1024);
1128 if (!ret) {
1129 range->start = newer_off;
1130 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1131 } else {
1132 break;
1133 }
1134 } else {
1135 if (ret > 0) {
1136 i += ret;
1137 last_len += ret << PAGE_CACHE_SHIFT;
1138 } else {
1139 i++;
1140 last_len = 0;
1141 }
1142 }
1143 }
1144
1145 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1146 filemap_flush(inode->i_mapping);
1147
1148 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1149 /* the filemap_flush will queue IO into the worker threads, but
1150 * we have to make sure the IO is actually started and that
1151 * ordered extents get created before we return
1152 */
1153 atomic_inc(&root->fs_info->async_submit_draining);
1154 while (atomic_read(&root->fs_info->nr_async_submits) ||
1155 atomic_read(&root->fs_info->async_delalloc_pages)) {
1156 wait_event(root->fs_info->async_submit_wait,
1157 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1158 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1159 }
1160 atomic_dec(&root->fs_info->async_submit_draining);
1161
1162 mutex_lock(&inode->i_mutex);
1163 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1164 mutex_unlock(&inode->i_mutex);
1165 }
1166
1167 disk_super = root->fs_info->super_copy;
1168 features = btrfs_super_incompat_flags(disk_super);
1169 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1170 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
1171 btrfs_set_super_incompat_flags(disk_super, features);
1172 }
1173
1174 ret = defrag_count;
1175
1176 out_ra:
1177 if (!file)
1178 kfree(ra);
1179 kfree(pages);
1180 return ret;
1181 }
1182
1183 static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
1184 void __user *arg)
1185 {
1186 u64 new_size;
1187 u64 old_size;
1188 u64 devid = 1;
1189 struct btrfs_ioctl_vol_args *vol_args;
1190 struct btrfs_trans_handle *trans;
1191 struct btrfs_device *device = NULL;
1192 char *sizestr;
1193 char *devstr = NULL;
1194 int ret = 0;
1195 int mod = 0;
1196
1197 if (root->fs_info->sb->s_flags & MS_RDONLY)
1198 return -EROFS;
1199
1200 if (!capable(CAP_SYS_ADMIN))
1201 return -EPERM;
1202
1203 vol_args = memdup_user(arg, sizeof(*vol_args));
1204 if (IS_ERR(vol_args))
1205 return PTR_ERR(vol_args);
1206
1207 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1208
1209 mutex_lock(&root->fs_info->volume_mutex);
1210 sizestr = vol_args->name;
1211 devstr = strchr(sizestr, ':');
1212 if (devstr) {
1213 char *end;
1214 sizestr = devstr + 1;
1215 *devstr = '\0';
1216 devstr = vol_args->name;
1217 devid = simple_strtoull(devstr, &end, 10);
1218 printk(KERN_INFO "resizing devid %llu\n",
1219 (unsigned long long)devid);
1220 }
1221 device = btrfs_find_device(root, devid, NULL, NULL);
1222 if (!device) {
1223 printk(KERN_INFO "resizer unable to find device %llu\n",
1224 (unsigned long long)devid);
1225 ret = -EINVAL;
1226 goto out_unlock;
1227 }
1228 if (!strcmp(sizestr, "max"))
1229 new_size = device->bdev->bd_inode->i_size;
1230 else {
1231 if (sizestr[0] == '-') {
1232 mod = -1;
1233 sizestr++;
1234 } else if (sizestr[0] == '+') {
1235 mod = 1;
1236 sizestr++;
1237 }
1238 new_size = memparse(sizestr, NULL);
1239 if (new_size == 0) {
1240 ret = -EINVAL;
1241 goto out_unlock;
1242 }
1243 }
1244
1245 old_size = device->total_bytes;
1246
1247 if (mod < 0) {
1248 if (new_size > old_size) {
1249 ret = -EINVAL;
1250 goto out_unlock;
1251 }
1252 new_size = old_size - new_size;
1253 } else if (mod > 0) {
1254 new_size = old_size + new_size;
1255 }
1256
1257 if (new_size < 256 * 1024 * 1024) {
1258 ret = -EINVAL;
1259 goto out_unlock;
1260 }
1261 if (new_size > device->bdev->bd_inode->i_size) {
1262 ret = -EFBIG;
1263 goto out_unlock;
1264 }
1265
1266 do_div(new_size, root->sectorsize);
1267 new_size *= root->sectorsize;
1268
1269 printk(KERN_INFO "new size for %s is %llu\n",
1270 device->name, (unsigned long long)new_size);
1271
1272 if (new_size > old_size) {
1273 trans = btrfs_start_transaction(root, 0);
1274 if (IS_ERR(trans)) {
1275 ret = PTR_ERR(trans);
1276 goto out_unlock;
1277 }
1278 ret = btrfs_grow_device(trans, device, new_size);
1279 btrfs_commit_transaction(trans, root);
1280 } else {
1281 ret = btrfs_shrink_device(device, new_size);
1282 }
1283
1284 out_unlock:
1285 mutex_unlock(&root->fs_info->volume_mutex);
1286 kfree(vol_args);
1287 return ret;
1288 }
1289
1290 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1291 char *name,
1292 unsigned long fd,
1293 int subvol,
1294 u64 *transid,
1295 bool readonly)
1296 {
1297 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1298 struct file *src_file;
1299 int namelen;
1300 int ret = 0;
1301
1302 if (root->fs_info->sb->s_flags & MS_RDONLY)
1303 return -EROFS;
1304
1305 namelen = strlen(name);
1306 if (strchr(name, '/')) {
1307 ret = -EINVAL;
1308 goto out;
1309 }
1310
1311 if (subvol) {
1312 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1313 NULL, transid, readonly);
1314 } else {
1315 struct inode *src_inode;
1316 src_file = fget(fd);
1317 if (!src_file) {
1318 ret = -EINVAL;
1319 goto out;
1320 }
1321
1322 src_inode = src_file->f_path.dentry->d_inode;
1323 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1324 printk(KERN_INFO "btrfs: Snapshot src from "
1325 "another FS\n");
1326 ret = -EINVAL;
1327 fput(src_file);
1328 goto out;
1329 }
1330 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1331 BTRFS_I(src_inode)->root,
1332 transid, readonly);
1333 fput(src_file);
1334 }
1335 out:
1336 return ret;
1337 }
1338
1339 static noinline int btrfs_ioctl_snap_create(struct file *file,
1340 void __user *arg, int subvol)
1341 {
1342 struct btrfs_ioctl_vol_args *vol_args;
1343 int ret;
1344
1345 vol_args = memdup_user(arg, sizeof(*vol_args));
1346 if (IS_ERR(vol_args))
1347 return PTR_ERR(vol_args);
1348 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1349
1350 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1351 vol_args->fd, subvol,
1352 NULL, false);
1353
1354 kfree(vol_args);
1355 return ret;
1356 }
1357
1358 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1359 void __user *arg, int subvol)
1360 {
1361 struct btrfs_ioctl_vol_args_v2 *vol_args;
1362 int ret;
1363 u64 transid = 0;
1364 u64 *ptr = NULL;
1365 bool readonly = false;
1366
1367 vol_args = memdup_user(arg, sizeof(*vol_args));
1368 if (IS_ERR(vol_args))
1369 return PTR_ERR(vol_args);
1370 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1371
1372 if (vol_args->flags &
1373 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
1374 ret = -EOPNOTSUPP;
1375 goto out;
1376 }
1377
1378 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1379 ptr = &transid;
1380 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1381 readonly = true;
1382
1383 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1384 vol_args->fd, subvol,
1385 ptr, readonly);
1386
1387 if (ret == 0 && ptr &&
1388 copy_to_user(arg +
1389 offsetof(struct btrfs_ioctl_vol_args_v2,
1390 transid), ptr, sizeof(*ptr)))
1391 ret = -EFAULT;
1392 out:
1393 kfree(vol_args);
1394 return ret;
1395 }
1396
1397 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1398 void __user *arg)
1399 {
1400 struct inode *inode = fdentry(file)->d_inode;
1401 struct btrfs_root *root = BTRFS_I(inode)->root;
1402 int ret = 0;
1403 u64 flags = 0;
1404
1405 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1406 return -EINVAL;
1407
1408 down_read(&root->fs_info->subvol_sem);
1409 if (btrfs_root_readonly(root))
1410 flags |= BTRFS_SUBVOL_RDONLY;
1411 up_read(&root->fs_info->subvol_sem);
1412
1413 if (copy_to_user(arg, &flags, sizeof(flags)))
1414 ret = -EFAULT;
1415
1416 return ret;
1417 }
1418
1419 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1420 void __user *arg)
1421 {
1422 struct inode *inode = fdentry(file)->d_inode;
1423 struct btrfs_root *root = BTRFS_I(inode)->root;
1424 struct btrfs_trans_handle *trans;
1425 u64 root_flags;
1426 u64 flags;
1427 int ret = 0;
1428
1429 if (root->fs_info->sb->s_flags & MS_RDONLY)
1430 return -EROFS;
1431
1432 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1433 return -EINVAL;
1434
1435 if (copy_from_user(&flags, arg, sizeof(flags)))
1436 return -EFAULT;
1437
1438 if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
1439 return -EINVAL;
1440
1441 if (flags & ~BTRFS_SUBVOL_RDONLY)
1442 return -EOPNOTSUPP;
1443
1444 if (!inode_owner_or_capable(inode))
1445 return -EACCES;
1446
1447 down_write(&root->fs_info->subvol_sem);
1448
1449 /* nothing to do */
1450 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1451 goto out;
1452
1453 root_flags = btrfs_root_flags(&root->root_item);
1454 if (flags & BTRFS_SUBVOL_RDONLY)
1455 btrfs_set_root_flags(&root->root_item,
1456 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1457 else
1458 btrfs_set_root_flags(&root->root_item,
1459 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1460
1461 trans = btrfs_start_transaction(root, 1);
1462 if (IS_ERR(trans)) {
1463 ret = PTR_ERR(trans);
1464 goto out_reset;
1465 }
1466
1467 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1468 &root->root_key, &root->root_item);
1469
1470 btrfs_commit_transaction(trans, root);
1471 out_reset:
1472 if (ret)
1473 btrfs_set_root_flags(&root->root_item, root_flags);
1474 out:
1475 up_write(&root->fs_info->subvol_sem);
1476 return ret;
1477 }
1478
1479 /*
1480 * helper to check if the subvolume references other subvolumes
1481 */
1482 static noinline int may_destroy_subvol(struct btrfs_root *root)
1483 {
1484 struct btrfs_path *path;
1485 struct btrfs_key key;
1486 int ret;
1487
1488 path = btrfs_alloc_path();
1489 if (!path)
1490 return -ENOMEM;
1491
1492 key.objectid = root->root_key.objectid;
1493 key.type = BTRFS_ROOT_REF_KEY;
1494 key.offset = (u64)-1;
1495
1496 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1497 &key, path, 0, 0);
1498 if (ret < 0)
1499 goto out;
1500 BUG_ON(ret == 0);
1501
1502 ret = 0;
1503 if (path->slots[0] > 0) {
1504 path->slots[0]--;
1505 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1506 if (key.objectid == root->root_key.objectid &&
1507 key.type == BTRFS_ROOT_REF_KEY)
1508 ret = -ENOTEMPTY;
1509 }
1510 out:
1511 btrfs_free_path(path);
1512 return ret;
1513 }
1514
1515 static noinline int key_in_sk(struct btrfs_key *key,
1516 struct btrfs_ioctl_search_key *sk)
1517 {
1518 struct btrfs_key test;
1519 int ret;
1520
1521 test.objectid = sk->min_objectid;
1522 test.type = sk->min_type;
1523 test.offset = sk->min_offset;
1524
1525 ret = btrfs_comp_cpu_keys(key, &test);
1526 if (ret < 0)
1527 return 0;
1528
1529 test.objectid = sk->max_objectid;
1530 test.type = sk->max_type;
1531 test.offset = sk->max_offset;
1532
1533 ret = btrfs_comp_cpu_keys(key, &test);
1534 if (ret > 0)
1535 return 0;
1536 return 1;
1537 }
1538
1539 static noinline int copy_to_sk(struct btrfs_root *root,
1540 struct btrfs_path *path,
1541 struct btrfs_key *key,
1542 struct btrfs_ioctl_search_key *sk,
1543 char *buf,
1544 unsigned long *sk_offset,
1545 int *num_found)
1546 {
1547 u64 found_transid;
1548 struct extent_buffer *leaf;
1549 struct btrfs_ioctl_search_header sh;
1550 unsigned long item_off;
1551 unsigned long item_len;
1552 int nritems;
1553 int i;
1554 int slot;
1555 int ret = 0;
1556
1557 leaf = path->nodes[0];
1558 slot = path->slots[0];
1559 nritems = btrfs_header_nritems(leaf);
1560
1561 if (btrfs_header_generation(leaf) > sk->max_transid) {
1562 i = nritems;
1563 goto advance_key;
1564 }
1565 found_transid = btrfs_header_generation(leaf);
1566
1567 for (i = slot; i < nritems; i++) {
1568 item_off = btrfs_item_ptr_offset(leaf, i);
1569 item_len = btrfs_item_size_nr(leaf, i);
1570
1571 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1572 item_len = 0;
1573
1574 if (sizeof(sh) + item_len + *sk_offset >
1575 BTRFS_SEARCH_ARGS_BUFSIZE) {
1576 ret = 1;
1577 goto overflow;
1578 }
1579
1580 btrfs_item_key_to_cpu(leaf, key, i);
1581 if (!key_in_sk(key, sk))
1582 continue;
1583
1584 sh.objectid = key->objectid;
1585 sh.offset = key->offset;
1586 sh.type = key->type;
1587 sh.len = item_len;
1588 sh.transid = found_transid;
1589
1590 /* copy search result header */
1591 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1592 *sk_offset += sizeof(sh);
1593
1594 if (item_len) {
1595 char *p = buf + *sk_offset;
1596 /* copy the item */
1597 read_extent_buffer(leaf, p,
1598 item_off, item_len);
1599 *sk_offset += item_len;
1600 }
1601 (*num_found)++;
1602
1603 if (*num_found >= sk->nr_items)
1604 break;
1605 }
1606 advance_key:
1607 ret = 0;
1608 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1609 key->offset++;
1610 else if (key->type < (u8)-1 && key->type < sk->max_type) {
1611 key->offset = 0;
1612 key->type++;
1613 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1614 key->offset = 0;
1615 key->type = 0;
1616 key->objectid++;
1617 } else
1618 ret = 1;
1619 overflow:
1620 return ret;
1621 }
1622
1623 static noinline int search_ioctl(struct inode *inode,
1624 struct btrfs_ioctl_search_args *args)
1625 {
1626 struct btrfs_root *root;
1627 struct btrfs_key key;
1628 struct btrfs_key max_key;
1629 struct btrfs_path *path;
1630 struct btrfs_ioctl_search_key *sk = &args->key;
1631 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1632 int ret;
1633 int num_found = 0;
1634 unsigned long sk_offset = 0;
1635
1636 path = btrfs_alloc_path();
1637 if (!path)
1638 return -ENOMEM;
1639
1640 if (sk->tree_id == 0) {
1641 /* search the root of the inode that was passed */
1642 root = BTRFS_I(inode)->root;
1643 } else {
1644 key.objectid = sk->tree_id;
1645 key.type = BTRFS_ROOT_ITEM_KEY;
1646 key.offset = (u64)-1;
1647 root = btrfs_read_fs_root_no_name(info, &key);
1648 if (IS_ERR(root)) {
1649 printk(KERN_ERR "could not find root %llu\n",
1650 sk->tree_id);
1651 btrfs_free_path(path);
1652 return -ENOENT;
1653 }
1654 }
1655
1656 key.objectid = sk->min_objectid;
1657 key.type = sk->min_type;
1658 key.offset = sk->min_offset;
1659
1660 max_key.objectid = sk->max_objectid;
1661 max_key.type = sk->max_type;
1662 max_key.offset = sk->max_offset;
1663
1664 path->keep_locks = 1;
1665
1666 while(1) {
1667 ret = btrfs_search_forward(root, &key, &max_key, path, 0,
1668 sk->min_transid);
1669 if (ret != 0) {
1670 if (ret > 0)
1671 ret = 0;
1672 goto err;
1673 }
1674 ret = copy_to_sk(root, path, &key, sk, args->buf,
1675 &sk_offset, &num_found);
1676 btrfs_release_path(path);
1677 if (ret || num_found >= sk->nr_items)
1678 break;
1679
1680 }
1681 ret = 0;
1682 err:
1683 sk->nr_items = num_found;
1684 btrfs_free_path(path);
1685 return ret;
1686 }
1687
1688 static noinline int btrfs_ioctl_tree_search(struct file *file,
1689 void __user *argp)
1690 {
1691 struct btrfs_ioctl_search_args *args;
1692 struct inode *inode;
1693 int ret;
1694
1695 if (!capable(CAP_SYS_ADMIN))
1696 return -EPERM;
1697
1698 args = memdup_user(argp, sizeof(*args));
1699 if (IS_ERR(args))
1700 return PTR_ERR(args);
1701
1702 inode = fdentry(file)->d_inode;
1703 ret = search_ioctl(inode, args);
1704 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1705 ret = -EFAULT;
1706 kfree(args);
1707 return ret;
1708 }
1709
1710 /*
1711 * Search INODE_REFs to identify path name of 'dirid' directory
1712 * in a 'tree_id' tree. and sets path name to 'name'.
1713 */
1714 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1715 u64 tree_id, u64 dirid, char *name)
1716 {
1717 struct btrfs_root *root;
1718 struct btrfs_key key;
1719 char *ptr;
1720 int ret = -1;
1721 int slot;
1722 int len;
1723 int total_len = 0;
1724 struct btrfs_inode_ref *iref;
1725 struct extent_buffer *l;
1726 struct btrfs_path *path;
1727
1728 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1729 name[0]='\0';
1730 return 0;
1731 }
1732
1733 path = btrfs_alloc_path();
1734 if (!path)
1735 return -ENOMEM;
1736
1737 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1738
1739 key.objectid = tree_id;
1740 key.type = BTRFS_ROOT_ITEM_KEY;
1741 key.offset = (u64)-1;
1742 root = btrfs_read_fs_root_no_name(info, &key);
1743 if (IS_ERR(root)) {
1744 printk(KERN_ERR "could not find root %llu\n", tree_id);
1745 ret = -ENOENT;
1746 goto out;
1747 }
1748
1749 key.objectid = dirid;
1750 key.type = BTRFS_INODE_REF_KEY;
1751 key.offset = (u64)-1;
1752
1753 while(1) {
1754 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1755 if (ret < 0)
1756 goto out;
1757
1758 l = path->nodes[0];
1759 slot = path->slots[0];
1760 if (ret > 0 && slot > 0)
1761 slot--;
1762 btrfs_item_key_to_cpu(l, &key, slot);
1763
1764 if (ret > 0 && (key.objectid != dirid ||
1765 key.type != BTRFS_INODE_REF_KEY)) {
1766 ret = -ENOENT;
1767 goto out;
1768 }
1769
1770 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1771 len = btrfs_inode_ref_name_len(l, iref);
1772 ptr -= len + 1;
1773 total_len += len + 1;
1774 if (ptr < name)
1775 goto out;
1776
1777 *(ptr + len) = '/';
1778 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1779
1780 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1781 break;
1782
1783 btrfs_release_path(path);
1784 key.objectid = key.offset;
1785 key.offset = (u64)-1;
1786 dirid = key.objectid;
1787 }
1788 if (ptr < name)
1789 goto out;
1790 memmove(name, ptr, total_len);
1791 name[total_len]='\0';
1792 ret = 0;
1793 out:
1794 btrfs_free_path(path);
1795 return ret;
1796 }
1797
1798 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
1799 void __user *argp)
1800 {
1801 struct btrfs_ioctl_ino_lookup_args *args;
1802 struct inode *inode;
1803 int ret;
1804
1805 if (!capable(CAP_SYS_ADMIN))
1806 return -EPERM;
1807
1808 args = memdup_user(argp, sizeof(*args));
1809 if (IS_ERR(args))
1810 return PTR_ERR(args);
1811
1812 inode = fdentry(file)->d_inode;
1813
1814 if (args->treeid == 0)
1815 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
1816
1817 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
1818 args->treeid, args->objectid,
1819 args->name);
1820
1821 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1822 ret = -EFAULT;
1823
1824 kfree(args);
1825 return ret;
1826 }
1827
1828 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
1829 void __user *arg)
1830 {
1831 struct dentry *parent = fdentry(file);
1832 struct dentry *dentry;
1833 struct inode *dir = parent->d_inode;
1834 struct inode *inode;
1835 struct btrfs_root *root = BTRFS_I(dir)->root;
1836 struct btrfs_root *dest = NULL;
1837 struct btrfs_ioctl_vol_args *vol_args;
1838 struct btrfs_trans_handle *trans;
1839 int namelen;
1840 int ret;
1841 int err = 0;
1842
1843 vol_args = memdup_user(arg, sizeof(*vol_args));
1844 if (IS_ERR(vol_args))
1845 return PTR_ERR(vol_args);
1846
1847 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1848 namelen = strlen(vol_args->name);
1849 if (strchr(vol_args->name, '/') ||
1850 strncmp(vol_args->name, "..", namelen) == 0) {
1851 err = -EINVAL;
1852 goto out;
1853 }
1854
1855 err = mnt_want_write(file->f_path.mnt);
1856 if (err)
1857 goto out;
1858
1859 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
1860 dentry = lookup_one_len(vol_args->name, parent, namelen);
1861 if (IS_ERR(dentry)) {
1862 err = PTR_ERR(dentry);
1863 goto out_unlock_dir;
1864 }
1865
1866 if (!dentry->d_inode) {
1867 err = -ENOENT;
1868 goto out_dput;
1869 }
1870
1871 inode = dentry->d_inode;
1872 dest = BTRFS_I(inode)->root;
1873 if (!capable(CAP_SYS_ADMIN)){
1874 /*
1875 * Regular user. Only allow this with a special mount
1876 * option, when the user has write+exec access to the
1877 * subvol root, and when rmdir(2) would have been
1878 * allowed.
1879 *
1880 * Note that this is _not_ check that the subvol is
1881 * empty or doesn't contain data that we wouldn't
1882 * otherwise be able to delete.
1883 *
1884 * Users who want to delete empty subvols should try
1885 * rmdir(2).
1886 */
1887 err = -EPERM;
1888 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
1889 goto out_dput;
1890
1891 /*
1892 * Do not allow deletion if the parent dir is the same
1893 * as the dir to be deleted. That means the ioctl
1894 * must be called on the dentry referencing the root
1895 * of the subvol, not a random directory contained
1896 * within it.
1897 */
1898 err = -EINVAL;
1899 if (root == dest)
1900 goto out_dput;
1901
1902 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
1903 if (err)
1904 goto out_dput;
1905
1906 /* check if subvolume may be deleted by a non-root user */
1907 err = btrfs_may_delete(dir, dentry, 1);
1908 if (err)
1909 goto out_dput;
1910 }
1911
1912 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1913 err = -EINVAL;
1914 goto out_dput;
1915 }
1916
1917 mutex_lock(&inode->i_mutex);
1918 err = d_invalidate(dentry);
1919 if (err)
1920 goto out_unlock;
1921
1922 down_write(&root->fs_info->subvol_sem);
1923
1924 err = may_destroy_subvol(dest);
1925 if (err)
1926 goto out_up_write;
1927
1928 trans = btrfs_start_transaction(root, 0);
1929 if (IS_ERR(trans)) {
1930 err = PTR_ERR(trans);
1931 goto out_up_write;
1932 }
1933 trans->block_rsv = &root->fs_info->global_block_rsv;
1934
1935 ret = btrfs_unlink_subvol(trans, root, dir,
1936 dest->root_key.objectid,
1937 dentry->d_name.name,
1938 dentry->d_name.len);
1939 BUG_ON(ret);
1940
1941 btrfs_record_root_in_trans(trans, dest);
1942
1943 memset(&dest->root_item.drop_progress, 0,
1944 sizeof(dest->root_item.drop_progress));
1945 dest->root_item.drop_level = 0;
1946 btrfs_set_root_refs(&dest->root_item, 0);
1947
1948 if (!xchg(&dest->orphan_item_inserted, 1)) {
1949 ret = btrfs_insert_orphan_item(trans,
1950 root->fs_info->tree_root,
1951 dest->root_key.objectid);
1952 BUG_ON(ret);
1953 }
1954
1955 ret = btrfs_end_transaction(trans, root);
1956 BUG_ON(ret);
1957 inode->i_flags |= S_DEAD;
1958 out_up_write:
1959 up_write(&root->fs_info->subvol_sem);
1960 out_unlock:
1961 mutex_unlock(&inode->i_mutex);
1962 if (!err) {
1963 shrink_dcache_sb(root->fs_info->sb);
1964 btrfs_invalidate_inodes(dest);
1965 d_delete(dentry);
1966 }
1967 out_dput:
1968 dput(dentry);
1969 out_unlock_dir:
1970 mutex_unlock(&dir->i_mutex);
1971 mnt_drop_write(file->f_path.mnt);
1972 out:
1973 kfree(vol_args);
1974 return err;
1975 }
1976
1977 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
1978 {
1979 struct inode *inode = fdentry(file)->d_inode;
1980 struct btrfs_root *root = BTRFS_I(inode)->root;
1981 struct btrfs_ioctl_defrag_range_args *range;
1982 int ret;
1983
1984 if (btrfs_root_readonly(root))
1985 return -EROFS;
1986
1987 ret = mnt_want_write(file->f_path.mnt);
1988 if (ret)
1989 return ret;
1990
1991 switch (inode->i_mode & S_IFMT) {
1992 case S_IFDIR:
1993 if (!capable(CAP_SYS_ADMIN)) {
1994 ret = -EPERM;
1995 goto out;
1996 }
1997 ret = btrfs_defrag_root(root, 0);
1998 if (ret)
1999 goto out;
2000 ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
2001 break;
2002 case S_IFREG:
2003 if (!(file->f_mode & FMODE_WRITE)) {
2004 ret = -EINVAL;
2005 goto out;
2006 }
2007
2008 range = kzalloc(sizeof(*range), GFP_KERNEL);
2009 if (!range) {
2010 ret = -ENOMEM;
2011 goto out;
2012 }
2013
2014 if (argp) {
2015 if (copy_from_user(range, argp,
2016 sizeof(*range))) {
2017 ret = -EFAULT;
2018 kfree(range);
2019 goto out;
2020 }
2021 /* compression requires us to start the IO */
2022 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2023 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2024 range->extent_thresh = (u32)-1;
2025 }
2026 } else {
2027 /* the rest are all set to zero by kzalloc */
2028 range->len = (u64)-1;
2029 }
2030 ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
2031 range, 0, 0);
2032 if (ret > 0)
2033 ret = 0;
2034 kfree(range);
2035 break;
2036 default:
2037 ret = -EINVAL;
2038 }
2039 out:
2040 mnt_drop_write(file->f_path.mnt);
2041 return ret;
2042 }
2043
2044 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2045 {
2046 struct btrfs_ioctl_vol_args *vol_args;
2047 int ret;
2048
2049 if (!capable(CAP_SYS_ADMIN))
2050 return -EPERM;
2051
2052 vol_args = memdup_user(arg, sizeof(*vol_args));
2053 if (IS_ERR(vol_args))
2054 return PTR_ERR(vol_args);
2055
2056 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2057 ret = btrfs_init_new_device(root, vol_args->name);
2058
2059 kfree(vol_args);
2060 return ret;
2061 }
2062
2063 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
2064 {
2065 struct btrfs_ioctl_vol_args *vol_args;
2066 int ret;
2067
2068 if (!capable(CAP_SYS_ADMIN))
2069 return -EPERM;
2070
2071 if (root->fs_info->sb->s_flags & MS_RDONLY)
2072 return -EROFS;
2073
2074 vol_args = memdup_user(arg, sizeof(*vol_args));
2075 if (IS_ERR(vol_args))
2076 return PTR_ERR(vol_args);
2077
2078 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2079 ret = btrfs_rm_device(root, vol_args->name);
2080
2081 kfree(vol_args);
2082 return ret;
2083 }
2084
2085 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2086 {
2087 struct btrfs_ioctl_fs_info_args *fi_args;
2088 struct btrfs_device *device;
2089 struct btrfs_device *next;
2090 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2091 int ret = 0;
2092
2093 if (!capable(CAP_SYS_ADMIN))
2094 return -EPERM;
2095
2096 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2097 if (!fi_args)
2098 return -ENOMEM;
2099
2100 fi_args->num_devices = fs_devices->num_devices;
2101 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2102
2103 mutex_lock(&fs_devices->device_list_mutex);
2104 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2105 if (device->devid > fi_args->max_id)
2106 fi_args->max_id = device->devid;
2107 }
2108 mutex_unlock(&fs_devices->device_list_mutex);
2109
2110 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2111 ret = -EFAULT;
2112
2113 kfree(fi_args);
2114 return ret;
2115 }
2116
2117 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2118 {
2119 struct btrfs_ioctl_dev_info_args *di_args;
2120 struct btrfs_device *dev;
2121 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2122 int ret = 0;
2123 char *s_uuid = NULL;
2124 char empty_uuid[BTRFS_UUID_SIZE] = {0};
2125
2126 if (!capable(CAP_SYS_ADMIN))
2127 return -EPERM;
2128
2129 di_args = memdup_user(arg, sizeof(*di_args));
2130 if (IS_ERR(di_args))
2131 return PTR_ERR(di_args);
2132
2133 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2134 s_uuid = di_args->uuid;
2135
2136 mutex_lock(&fs_devices->device_list_mutex);
2137 dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL);
2138 mutex_unlock(&fs_devices->device_list_mutex);
2139
2140 if (!dev) {
2141 ret = -ENODEV;
2142 goto out;
2143 }
2144
2145 di_args->devid = dev->devid;
2146 di_args->bytes_used = dev->bytes_used;
2147 di_args->total_bytes = dev->total_bytes;
2148 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2149 strncpy(di_args->path, dev->name, sizeof(di_args->path));
2150
2151 out:
2152 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2153 ret = -EFAULT;
2154
2155 kfree(di_args);
2156 return ret;
2157 }
2158
2159 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2160 u64 off, u64 olen, u64 destoff)
2161 {
2162 struct inode *inode = fdentry(file)->d_inode;
2163 struct btrfs_root *root = BTRFS_I(inode)->root;
2164 struct file *src_file;
2165 struct inode *src;
2166 struct btrfs_trans_handle *trans;
2167 struct btrfs_path *path;
2168 struct extent_buffer *leaf;
2169 char *buf;
2170 struct btrfs_key key;
2171 u32 nritems;
2172 int slot;
2173 int ret;
2174 u64 len = olen;
2175 u64 bs = root->fs_info->sb->s_blocksize;
2176 u64 hint_byte;
2177
2178 /*
2179 * TODO:
2180 * - split compressed inline extents. annoying: we need to
2181 * decompress into destination's address_space (the file offset
2182 * may change, so source mapping won't do), then recompress (or
2183 * otherwise reinsert) a subrange.
2184 * - allow ranges within the same file to be cloned (provided
2185 * they don't overlap)?
2186 */
2187
2188 /* the destination must be opened for writing */
2189 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2190 return -EINVAL;
2191
2192 if (btrfs_root_readonly(root))
2193 return -EROFS;
2194
2195 ret = mnt_want_write(file->f_path.mnt);
2196 if (ret)
2197 return ret;
2198
2199 src_file = fget(srcfd);
2200 if (!src_file) {
2201 ret = -EBADF;
2202 goto out_drop_write;
2203 }
2204
2205 src = src_file->f_dentry->d_inode;
2206
2207 ret = -EINVAL;
2208 if (src == inode)
2209 goto out_fput;
2210
2211 /* the src must be open for reading */
2212 if (!(src_file->f_mode & FMODE_READ))
2213 goto out_fput;
2214
2215 /* don't make the dst file partly checksummed */
2216 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2217 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2218 goto out_fput;
2219
2220 ret = -EISDIR;
2221 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2222 goto out_fput;
2223
2224 ret = -EXDEV;
2225 if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
2226 goto out_fput;
2227
2228 ret = -ENOMEM;
2229 buf = vmalloc(btrfs_level_size(root, 0));
2230 if (!buf)
2231 goto out_fput;
2232
2233 path = btrfs_alloc_path();
2234 if (!path) {
2235 vfree(buf);
2236 goto out_fput;
2237 }
2238 path->reada = 2;
2239
2240 if (inode < src) {
2241 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2242 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2243 } else {
2244 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2245 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2246 }
2247
2248 /* determine range to clone */
2249 ret = -EINVAL;
2250 if (off + len > src->i_size || off + len < off)
2251 goto out_unlock;
2252 if (len == 0)
2253 olen = len = src->i_size - off;
2254 /* if we extend to eof, continue to block boundary */
2255 if (off + len == src->i_size)
2256 len = ALIGN(src->i_size, bs) - off;
2257
2258 /* verify the end result is block aligned */
2259 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2260 !IS_ALIGNED(destoff, bs))
2261 goto out_unlock;
2262
2263 if (destoff > inode->i_size) {
2264 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2265 if (ret)
2266 goto out_unlock;
2267 }
2268
2269 /* truncate page cache pages from target inode range */
2270 truncate_inode_pages_range(&inode->i_data, destoff,
2271 PAGE_CACHE_ALIGN(destoff + len) - 1);
2272
2273 /* do any pending delalloc/csum calc on src, one way or
2274 another, and lock file content */
2275 while (1) {
2276 struct btrfs_ordered_extent *ordered;
2277 lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2278 ordered = btrfs_lookup_first_ordered_extent(src, off+len);
2279 if (!ordered &&
2280 !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len,
2281 EXTENT_DELALLOC, 0, NULL))
2282 break;
2283 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2284 if (ordered)
2285 btrfs_put_ordered_extent(ordered);
2286 btrfs_wait_ordered_range(src, off, len);
2287 }
2288
2289 /* clone data */
2290 key.objectid = btrfs_ino(src);
2291 key.type = BTRFS_EXTENT_DATA_KEY;
2292 key.offset = 0;
2293
2294 while (1) {
2295 /*
2296 * note the key will change type as we walk through the
2297 * tree.
2298 */
2299 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2300 if (ret < 0)
2301 goto out;
2302
2303 nritems = btrfs_header_nritems(path->nodes[0]);
2304 if (path->slots[0] >= nritems) {
2305 ret = btrfs_next_leaf(root, path);
2306 if (ret < 0)
2307 goto out;
2308 if (ret > 0)
2309 break;
2310 nritems = btrfs_header_nritems(path->nodes[0]);
2311 }
2312 leaf = path->nodes[0];
2313 slot = path->slots[0];
2314
2315 btrfs_item_key_to_cpu(leaf, &key, slot);
2316 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2317 key.objectid != btrfs_ino(src))
2318 break;
2319
2320 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2321 struct btrfs_file_extent_item *extent;
2322 int type;
2323 u32 size;
2324 struct btrfs_key new_key;
2325 u64 disko = 0, diskl = 0;
2326 u64 datao = 0, datal = 0;
2327 u8 comp;
2328 u64 endoff;
2329
2330 size = btrfs_item_size_nr(leaf, slot);
2331 read_extent_buffer(leaf, buf,
2332 btrfs_item_ptr_offset(leaf, slot),
2333 size);
2334
2335 extent = btrfs_item_ptr(leaf, slot,
2336 struct btrfs_file_extent_item);
2337 comp = btrfs_file_extent_compression(leaf, extent);
2338 type = btrfs_file_extent_type(leaf, extent);
2339 if (type == BTRFS_FILE_EXTENT_REG ||
2340 type == BTRFS_FILE_EXTENT_PREALLOC) {
2341 disko = btrfs_file_extent_disk_bytenr(leaf,
2342 extent);
2343 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2344 extent);
2345 datao = btrfs_file_extent_offset(leaf, extent);
2346 datal = btrfs_file_extent_num_bytes(leaf,
2347 extent);
2348 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2349 /* take upper bound, may be compressed */
2350 datal = btrfs_file_extent_ram_bytes(leaf,
2351 extent);
2352 }
2353 btrfs_release_path(path);
2354
2355 if (key.offset + datal <= off ||
2356 key.offset >= off+len)
2357 goto next;
2358
2359 memcpy(&new_key, &key, sizeof(new_key));
2360 new_key.objectid = btrfs_ino(inode);
2361 if (off <= key.offset)
2362 new_key.offset = key.offset + destoff - off;
2363 else
2364 new_key.offset = destoff;
2365
2366 /*
2367 * 1 - adjusting old extent (we may have to split it)
2368 * 1 - add new extent
2369 * 1 - inode update
2370 */
2371 trans = btrfs_start_transaction(root, 3);
2372 if (IS_ERR(trans)) {
2373 ret = PTR_ERR(trans);
2374 goto out;
2375 }
2376
2377 if (type == BTRFS_FILE_EXTENT_REG ||
2378 type == BTRFS_FILE_EXTENT_PREALLOC) {
2379 /*
2380 * a | --- range to clone ---| b
2381 * | ------------- extent ------------- |
2382 */
2383
2384 /* substract range b */
2385 if (key.offset + datal > off + len)
2386 datal = off + len - key.offset;
2387
2388 /* substract range a */
2389 if (off > key.offset) {
2390 datao += off - key.offset;
2391 datal -= off - key.offset;
2392 }
2393
2394 ret = btrfs_drop_extents(trans, inode,
2395 new_key.offset,
2396 new_key.offset + datal,
2397 &hint_byte, 1);
2398 BUG_ON(ret);
2399
2400 ret = btrfs_insert_empty_item(trans, root, path,
2401 &new_key, size);
2402 BUG_ON(ret);
2403
2404 leaf = path->nodes[0];
2405 slot = path->slots[0];
2406 write_extent_buffer(leaf, buf,
2407 btrfs_item_ptr_offset(leaf, slot),
2408 size);
2409
2410 extent = btrfs_item_ptr(leaf, slot,
2411 struct btrfs_file_extent_item);
2412
2413 /* disko == 0 means it's a hole */
2414 if (!disko)
2415 datao = 0;
2416
2417 btrfs_set_file_extent_offset(leaf, extent,
2418 datao);
2419 btrfs_set_file_extent_num_bytes(leaf, extent,
2420 datal);
2421 if (disko) {
2422 inode_add_bytes(inode, datal);
2423 ret = btrfs_inc_extent_ref(trans, root,
2424 disko, diskl, 0,
2425 root->root_key.objectid,
2426 btrfs_ino(inode),
2427 new_key.offset - datao);
2428 BUG_ON(ret);
2429 }
2430 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2431 u64 skip = 0;
2432 u64 trim = 0;
2433 if (off > key.offset) {
2434 skip = off - key.offset;
2435 new_key.offset += skip;
2436 }
2437
2438 if (key.offset + datal > off+len)
2439 trim = key.offset + datal - (off+len);
2440
2441 if (comp && (skip || trim)) {
2442 ret = -EINVAL;
2443 btrfs_end_transaction(trans, root);
2444 goto out;
2445 }
2446 size -= skip + trim;
2447 datal -= skip + trim;
2448
2449 ret = btrfs_drop_extents(trans, inode,
2450 new_key.offset,
2451 new_key.offset + datal,
2452 &hint_byte, 1);
2453 BUG_ON(ret);
2454
2455 ret = btrfs_insert_empty_item(trans, root, path,
2456 &new_key, size);
2457 BUG_ON(ret);
2458
2459 if (skip) {
2460 u32 start =
2461 btrfs_file_extent_calc_inline_size(0);
2462 memmove(buf+start, buf+start+skip,
2463 datal);
2464 }
2465
2466 leaf = path->nodes[0];
2467 slot = path->slots[0];
2468 write_extent_buffer(leaf, buf,
2469 btrfs_item_ptr_offset(leaf, slot),
2470 size);
2471 inode_add_bytes(inode, datal);
2472 }
2473
2474 btrfs_mark_buffer_dirty(leaf);
2475 btrfs_release_path(path);
2476
2477 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2478
2479 /*
2480 * we round up to the block size at eof when
2481 * determining which extents to clone above,
2482 * but shouldn't round up the file size
2483 */
2484 endoff = new_key.offset + datal;
2485 if (endoff > destoff+olen)
2486 endoff = destoff+olen;
2487 if (endoff > inode->i_size)
2488 btrfs_i_size_write(inode, endoff);
2489
2490 ret = btrfs_update_inode(trans, root, inode);
2491 BUG_ON(ret);
2492 btrfs_end_transaction(trans, root);
2493 }
2494 next:
2495 btrfs_release_path(path);
2496 key.offset++;
2497 }
2498 ret = 0;
2499 out:
2500 btrfs_release_path(path);
2501 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2502 out_unlock:
2503 mutex_unlock(&src->i_mutex);
2504 mutex_unlock(&inode->i_mutex);
2505 vfree(buf);
2506 btrfs_free_path(path);
2507 out_fput:
2508 fput(src_file);
2509 out_drop_write:
2510 mnt_drop_write(file->f_path.mnt);
2511 return ret;
2512 }
2513
2514 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2515 {
2516 struct btrfs_ioctl_clone_range_args args;
2517
2518 if (copy_from_user(&args, argp, sizeof(args)))
2519 return -EFAULT;
2520 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2521 args.src_length, args.dest_offset);
2522 }
2523
2524 /*
2525 * there are many ways the trans_start and trans_end ioctls can lead
2526 * to deadlocks. They should only be used by applications that
2527 * basically own the machine, and have a very in depth understanding
2528 * of all the possible deadlocks and enospc problems.
2529 */
2530 static long btrfs_ioctl_trans_start(struct file *file)
2531 {
2532 struct inode *inode = fdentry(file)->d_inode;
2533 struct btrfs_root *root = BTRFS_I(inode)->root;
2534 struct btrfs_trans_handle *trans;
2535 int ret;
2536
2537 ret = -EPERM;
2538 if (!capable(CAP_SYS_ADMIN))
2539 goto out;
2540
2541 ret = -EINPROGRESS;
2542 if (file->private_data)
2543 goto out;
2544
2545 ret = -EROFS;
2546 if (btrfs_root_readonly(root))
2547 goto out;
2548
2549 ret = mnt_want_write(file->f_path.mnt);
2550 if (ret)
2551 goto out;
2552
2553 atomic_inc(&root->fs_info->open_ioctl_trans);
2554
2555 ret = -ENOMEM;
2556 trans = btrfs_start_ioctl_transaction(root);
2557 if (IS_ERR(trans))
2558 goto out_drop;
2559
2560 file->private_data = trans;
2561 return 0;
2562
2563 out_drop:
2564 atomic_dec(&root->fs_info->open_ioctl_trans);
2565 mnt_drop_write(file->f_path.mnt);
2566 out:
2567 return ret;
2568 }
2569
2570 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2571 {
2572 struct inode *inode = fdentry(file)->d_inode;
2573 struct btrfs_root *root = BTRFS_I(inode)->root;
2574 struct btrfs_root *new_root;
2575 struct btrfs_dir_item *di;
2576 struct btrfs_trans_handle *trans;
2577 struct btrfs_path *path;
2578 struct btrfs_key location;
2579 struct btrfs_disk_key disk_key;
2580 struct btrfs_super_block *disk_super;
2581 u64 features;
2582 u64 objectid = 0;
2583 u64 dir_id;
2584
2585 if (!capable(CAP_SYS_ADMIN))
2586 return -EPERM;
2587
2588 if (copy_from_user(&objectid, argp, sizeof(objectid)))
2589 return -EFAULT;
2590
2591 if (!objectid)
2592 objectid = root->root_key.objectid;
2593
2594 location.objectid = objectid;
2595 location.type = BTRFS_ROOT_ITEM_KEY;
2596 location.offset = (u64)-1;
2597
2598 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2599 if (IS_ERR(new_root))
2600 return PTR_ERR(new_root);
2601
2602 if (btrfs_root_refs(&new_root->root_item) == 0)
2603 return -ENOENT;
2604
2605 path = btrfs_alloc_path();
2606 if (!path)
2607 return -ENOMEM;
2608 path->leave_spinning = 1;
2609
2610 trans = btrfs_start_transaction(root, 1);
2611 if (IS_ERR(trans)) {
2612 btrfs_free_path(path);
2613 return PTR_ERR(trans);
2614 }
2615
2616 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
2617 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2618 dir_id, "default", 7, 1);
2619 if (IS_ERR_OR_NULL(di)) {
2620 btrfs_free_path(path);
2621 btrfs_end_transaction(trans, root);
2622 printk(KERN_ERR "Umm, you don't have the default dir item, "
2623 "this isn't going to work\n");
2624 return -ENOENT;
2625 }
2626
2627 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2628 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2629 btrfs_mark_buffer_dirty(path->nodes[0]);
2630 btrfs_free_path(path);
2631
2632 disk_super = root->fs_info->super_copy;
2633 features = btrfs_super_incompat_flags(disk_super);
2634 if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) {
2635 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL;
2636 btrfs_set_super_incompat_flags(disk_super, features);
2637 }
2638 btrfs_end_transaction(trans, root);
2639
2640 return 0;
2641 }
2642
2643 static void get_block_group_info(struct list_head *groups_list,
2644 struct btrfs_ioctl_space_info *space)
2645 {
2646 struct btrfs_block_group_cache *block_group;
2647
2648 space->total_bytes = 0;
2649 space->used_bytes = 0;
2650 space->flags = 0;
2651 list_for_each_entry(block_group, groups_list, list) {
2652 space->flags = block_group->flags;
2653 space->total_bytes += block_group->key.offset;
2654 space->used_bytes +=
2655 btrfs_block_group_used(&block_group->item);
2656 }
2657 }
2658
2659 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
2660 {
2661 struct btrfs_ioctl_space_args space_args;
2662 struct btrfs_ioctl_space_info space;
2663 struct btrfs_ioctl_space_info *dest;
2664 struct btrfs_ioctl_space_info *dest_orig;
2665 struct btrfs_ioctl_space_info __user *user_dest;
2666 struct btrfs_space_info *info;
2667 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2668 BTRFS_BLOCK_GROUP_SYSTEM,
2669 BTRFS_BLOCK_GROUP_METADATA,
2670 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
2671 int num_types = 4;
2672 int alloc_size;
2673 int ret = 0;
2674 u64 slot_count = 0;
2675 int i, c;
2676
2677 if (copy_from_user(&space_args,
2678 (struct btrfs_ioctl_space_args __user *)arg,
2679 sizeof(space_args)))
2680 return -EFAULT;
2681
2682 for (i = 0; i < num_types; i++) {
2683 struct btrfs_space_info *tmp;
2684
2685 info = NULL;
2686 rcu_read_lock();
2687 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2688 list) {
2689 if (tmp->flags == types[i]) {
2690 info = tmp;
2691 break;
2692 }
2693 }
2694 rcu_read_unlock();
2695
2696 if (!info)
2697 continue;
2698
2699 down_read(&info->groups_sem);
2700 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2701 if (!list_empty(&info->block_groups[c]))
2702 slot_count++;
2703 }
2704 up_read(&info->groups_sem);
2705 }
2706
2707 /* space_slots == 0 means they are asking for a count */
2708 if (space_args.space_slots == 0) {
2709 space_args.total_spaces = slot_count;
2710 goto out;
2711 }
2712
2713 slot_count = min_t(u64, space_args.space_slots, slot_count);
2714
2715 alloc_size = sizeof(*dest) * slot_count;
2716
2717 /* we generally have at most 6 or so space infos, one for each raid
2718 * level. So, a whole page should be more than enough for everyone
2719 */
2720 if (alloc_size > PAGE_CACHE_SIZE)
2721 return -ENOMEM;
2722
2723 space_args.total_spaces = 0;
2724 dest = kmalloc(alloc_size, GFP_NOFS);
2725 if (!dest)
2726 return -ENOMEM;
2727 dest_orig = dest;
2728
2729 /* now we have a buffer to copy into */
2730 for (i = 0; i < num_types; i++) {
2731 struct btrfs_space_info *tmp;
2732
2733 if (!slot_count)
2734 break;
2735
2736 info = NULL;
2737 rcu_read_lock();
2738 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2739 list) {
2740 if (tmp->flags == types[i]) {
2741 info = tmp;
2742 break;
2743 }
2744 }
2745 rcu_read_unlock();
2746
2747 if (!info)
2748 continue;
2749 down_read(&info->groups_sem);
2750 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2751 if (!list_empty(&info->block_groups[c])) {
2752 get_block_group_info(&info->block_groups[c],
2753 &space);
2754 memcpy(dest, &space, sizeof(space));
2755 dest++;
2756 space_args.total_spaces++;
2757 slot_count--;
2758 }
2759 if (!slot_count)
2760 break;
2761 }
2762 up_read(&info->groups_sem);
2763 }
2764
2765 user_dest = (struct btrfs_ioctl_space_info *)
2766 (arg + sizeof(struct btrfs_ioctl_space_args));
2767
2768 if (copy_to_user(user_dest, dest_orig, alloc_size))
2769 ret = -EFAULT;
2770
2771 kfree(dest_orig);
2772 out:
2773 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
2774 ret = -EFAULT;
2775
2776 return ret;
2777 }
2778
2779 /*
2780 * there are many ways the trans_start and trans_end ioctls can lead
2781 * to deadlocks. They should only be used by applications that
2782 * basically own the machine, and have a very in depth understanding
2783 * of all the possible deadlocks and enospc problems.
2784 */
2785 long btrfs_ioctl_trans_end(struct file *file)
2786 {
2787 struct inode *inode = fdentry(file)->d_inode;
2788 struct btrfs_root *root = BTRFS_I(inode)->root;
2789 struct btrfs_trans_handle *trans;
2790
2791 trans = file->private_data;
2792 if (!trans)
2793 return -EINVAL;
2794 file->private_data = NULL;
2795
2796 btrfs_end_transaction(trans, root);
2797
2798 atomic_dec(&root->fs_info->open_ioctl_trans);
2799
2800 mnt_drop_write(file->f_path.mnt);
2801 return 0;
2802 }
2803
2804 static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
2805 {
2806 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2807 struct btrfs_trans_handle *trans;
2808 u64 transid;
2809 int ret;
2810
2811 trans = btrfs_start_transaction(root, 0);
2812 if (IS_ERR(trans))
2813 return PTR_ERR(trans);
2814 transid = trans->transid;
2815 ret = btrfs_commit_transaction_async(trans, root, 0);
2816 if (ret) {
2817 btrfs_end_transaction(trans, root);
2818 return ret;
2819 }
2820
2821 if (argp)
2822 if (copy_to_user(argp, &transid, sizeof(transid)))
2823 return -EFAULT;
2824 return 0;
2825 }
2826
2827 static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
2828 {
2829 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2830 u64 transid;
2831
2832 if (argp) {
2833 if (copy_from_user(&transid, argp, sizeof(transid)))
2834 return -EFAULT;
2835 } else {
2836 transid = 0; /* current trans */
2837 }
2838 return btrfs_wait_for_commit(root, transid);
2839 }
2840
2841 static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg)
2842 {
2843 int ret;
2844 struct btrfs_ioctl_scrub_args *sa;
2845
2846 if (!capable(CAP_SYS_ADMIN))
2847 return -EPERM;
2848
2849 sa = memdup_user(arg, sizeof(*sa));
2850 if (IS_ERR(sa))
2851 return PTR_ERR(sa);
2852
2853 ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end,
2854 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY);
2855
2856 if (copy_to_user(arg, sa, sizeof(*sa)))
2857 ret = -EFAULT;
2858
2859 kfree(sa);
2860 return ret;
2861 }
2862
2863 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
2864 {
2865 if (!capable(CAP_SYS_ADMIN))
2866 return -EPERM;
2867
2868 return btrfs_scrub_cancel(root);
2869 }
2870
2871 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
2872 void __user *arg)
2873 {
2874 struct btrfs_ioctl_scrub_args *sa;
2875 int ret;
2876
2877 if (!capable(CAP_SYS_ADMIN))
2878 return -EPERM;
2879
2880 sa = memdup_user(arg, sizeof(*sa));
2881 if (IS_ERR(sa))
2882 return PTR_ERR(sa);
2883
2884 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
2885
2886 if (copy_to_user(arg, sa, sizeof(*sa)))
2887 ret = -EFAULT;
2888
2889 kfree(sa);
2890 return ret;
2891 }
2892
2893 long btrfs_ioctl(struct file *file, unsigned int
2894 cmd, unsigned long arg)
2895 {
2896 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2897 void __user *argp = (void __user *)arg;
2898
2899 switch (cmd) {
2900 case FS_IOC_GETFLAGS:
2901 return btrfs_ioctl_getflags(file, argp);
2902 case FS_IOC_SETFLAGS:
2903 return btrfs_ioctl_setflags(file, argp);
2904 case FS_IOC_GETVERSION:
2905 return btrfs_ioctl_getversion(file, argp);
2906 case FITRIM:
2907 return btrfs_ioctl_fitrim(file, argp);
2908 case BTRFS_IOC_SNAP_CREATE:
2909 return btrfs_ioctl_snap_create(file, argp, 0);
2910 case BTRFS_IOC_SNAP_CREATE_V2:
2911 return btrfs_ioctl_snap_create_v2(file, argp, 0);
2912 case BTRFS_IOC_SUBVOL_CREATE:
2913 return btrfs_ioctl_snap_create(file, argp, 1);
2914 case BTRFS_IOC_SNAP_DESTROY:
2915 return btrfs_ioctl_snap_destroy(file, argp);
2916 case BTRFS_IOC_SUBVOL_GETFLAGS:
2917 return btrfs_ioctl_subvol_getflags(file, argp);
2918 case BTRFS_IOC_SUBVOL_SETFLAGS:
2919 return btrfs_ioctl_subvol_setflags(file, argp);
2920 case BTRFS_IOC_DEFAULT_SUBVOL:
2921 return btrfs_ioctl_default_subvol(file, argp);
2922 case BTRFS_IOC_DEFRAG:
2923 return btrfs_ioctl_defrag(file, NULL);
2924 case BTRFS_IOC_DEFRAG_RANGE:
2925 return btrfs_ioctl_defrag(file, argp);
2926 case BTRFS_IOC_RESIZE:
2927 return btrfs_ioctl_resize(root, argp);
2928 case BTRFS_IOC_ADD_DEV:
2929 return btrfs_ioctl_add_dev(root, argp);
2930 case BTRFS_IOC_RM_DEV:
2931 return btrfs_ioctl_rm_dev(root, argp);
2932 case BTRFS_IOC_FS_INFO:
2933 return btrfs_ioctl_fs_info(root, argp);
2934 case BTRFS_IOC_DEV_INFO:
2935 return btrfs_ioctl_dev_info(root, argp);
2936 case BTRFS_IOC_BALANCE:
2937 return btrfs_balance(root->fs_info->dev_root);
2938 case BTRFS_IOC_CLONE:
2939 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
2940 case BTRFS_IOC_CLONE_RANGE:
2941 return btrfs_ioctl_clone_range(file, argp);
2942 case BTRFS_IOC_TRANS_START:
2943 return btrfs_ioctl_trans_start(file);
2944 case BTRFS_IOC_TRANS_END:
2945 return btrfs_ioctl_trans_end(file);
2946 case BTRFS_IOC_TREE_SEARCH:
2947 return btrfs_ioctl_tree_search(file, argp);
2948 case BTRFS_IOC_INO_LOOKUP:
2949 return btrfs_ioctl_ino_lookup(file, argp);
2950 case BTRFS_IOC_SPACE_INFO:
2951 return btrfs_ioctl_space_info(root, argp);
2952 case BTRFS_IOC_SYNC:
2953 btrfs_sync_fs(file->f_dentry->d_sb, 1);
2954 return 0;
2955 case BTRFS_IOC_START_SYNC:
2956 return btrfs_ioctl_start_sync(file, argp);
2957 case BTRFS_IOC_WAIT_SYNC:
2958 return btrfs_ioctl_wait_sync(file, argp);
2959 case BTRFS_IOC_SCRUB:
2960 return btrfs_ioctl_scrub(root, argp);
2961 case BTRFS_IOC_SCRUB_CANCEL:
2962 return btrfs_ioctl_scrub_cancel(root, argp);
2963 case BTRFS_IOC_SCRUB_PROGRESS:
2964 return btrfs_ioctl_scrub_progress(root, argp);
2965 }
2966
2967 return -ENOTTY;
2968 }
Linux kernel - Deliverables
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