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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. */
56static 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 */
69static 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 */
99void 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 */
122void 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
140static 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
150static 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
165static 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
264static 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
271static 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
315static noinline int create_subvol(struct btrfs_root *root,
316 struct dentry *dentry,
317 char *name, int namelen,
318 u64 *async_transid)
319{
320 struct btrfs_trans_handle *trans;
321 struct btrfs_key key;
322 struct btrfs_root_item root_item;
323 struct btrfs_inode_item *inode_item;
324 struct extent_buffer *leaf;
325 struct btrfs_root *new_root;
326 struct dentry *parent = dentry->d_parent;
327 struct inode *dir;
328 int ret;
329 int err;
330 u64 objectid;
331 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
332 u64 index = 0;
333
334 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
335 if (ret)
336 return ret;
337
338 dir = parent->d_inode;
339
340 /*
341 * 1 - inode item
342 * 2 - refs
343 * 1 - root item
344 * 2 - dir items
345 */
346 trans = btrfs_start_transaction(root, 6);
347 if (IS_ERR(trans))
348 return PTR_ERR(trans);
349
350 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
351 0, objectid, NULL, 0, 0, 0);
352 if (IS_ERR(leaf)) {
353 ret = PTR_ERR(leaf);
354 goto fail;
355 }
356
357 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
358 btrfs_set_header_bytenr(leaf, leaf->start);
359 btrfs_set_header_generation(leaf, trans->transid);
360 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
361 btrfs_set_header_owner(leaf, objectid);
362
363 write_extent_buffer(leaf, root->fs_info->fsid,
364 (unsigned long)btrfs_header_fsid(leaf),
365 BTRFS_FSID_SIZE);
366 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
367 (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
368 BTRFS_UUID_SIZE);
369 btrfs_mark_buffer_dirty(leaf);
370
371 inode_item = &root_item.inode;
372 memset(inode_item, 0, sizeof(*inode_item));
373 inode_item->generation = cpu_to_le64(1);
374 inode_item->size = cpu_to_le64(3);
375 inode_item->nlink = cpu_to_le32(1);
376 inode_item->nbytes = cpu_to_le64(root->leafsize);
377 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
378
379 root_item.flags = 0;
380 root_item.byte_limit = 0;
381 inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
382
383 btrfs_set_root_bytenr(&root_item, leaf->start);
384 btrfs_set_root_generation(&root_item, trans->transid);
385 btrfs_set_root_level(&root_item, 0);
386 btrfs_set_root_refs(&root_item, 1);
387 btrfs_set_root_used(&root_item, leaf->len);
388 btrfs_set_root_last_snapshot(&root_item, 0);
389
390 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
391 root_item.drop_level = 0;
392
393 btrfs_tree_unlock(leaf);
394 free_extent_buffer(leaf);
395 leaf = NULL;
396
397 btrfs_set_root_dirid(&root_item, new_dirid);
398
399 key.objectid = objectid;
400 key.offset = 0;
401 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
402 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
403 &root_item);
404 if (ret)
405 goto fail;
406
407 key.offset = (u64)-1;
408 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
409 BUG_ON(IS_ERR(new_root));
410
411 btrfs_record_root_in_trans(trans, new_root);
412
413 ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
414 /*
415 * insert the directory item
416 */
417 ret = btrfs_set_inode_index(dir, &index);
418 BUG_ON(ret);
419
420 ret = btrfs_insert_dir_item(trans, root,
421 name, namelen, dir, &key,
422 BTRFS_FT_DIR, index);
423 if (ret)
424 goto fail;
425
426 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
427 ret = btrfs_update_inode(trans, root, dir);
428 BUG_ON(ret);
429
430 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
431 objectid, root->root_key.objectid,
432 btrfs_ino(dir), index, name, namelen);
433
434 BUG_ON(ret);
435
436 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
437fail:
438 if (async_transid) {
439 *async_transid = trans->transid;
440 err = btrfs_commit_transaction_async(trans, root, 1);
441 } else {
442 err = btrfs_commit_transaction(trans, root);
443 }
444 if (err && !ret)
445 ret = err;
446 return ret;
447}
448
449static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
450 char *name, int namelen, u64 *async_transid,
451 bool readonly)
452{
453 struct inode *inode;
454 struct btrfs_pending_snapshot *pending_snapshot;
455 struct btrfs_trans_handle *trans;
456 int ret;
457
458 if (!root->ref_cows)
459 return -EINVAL;
460
461 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
462 if (!pending_snapshot)
463 return -ENOMEM;
464
465 btrfs_init_block_rsv(&pending_snapshot->block_rsv);
466 pending_snapshot->dentry = dentry;
467 pending_snapshot->root = root;
468 pending_snapshot->readonly = readonly;
469
470 trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
471 if (IS_ERR(trans)) {
472 ret = PTR_ERR(trans);
473 goto fail;
474 }
475
476 ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
477 BUG_ON(ret);
478
479 spin_lock(&root->fs_info->trans_lock);
480 list_add(&pending_snapshot->list,
481 &trans->transaction->pending_snapshots);
482 spin_unlock(&root->fs_info->trans_lock);
483 if (async_transid) {
484 *async_transid = trans->transid;
485 ret = btrfs_commit_transaction_async(trans,
486 root->fs_info->extent_root, 1);
487 } else {
488 ret = btrfs_commit_transaction(trans,
489 root->fs_info->extent_root);
490 }
491 BUG_ON(ret);
492
493 ret = pending_snapshot->error;
494 if (ret)
495 goto fail;
496
497 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
498 if (ret)
499 goto fail;
500
501 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
502 if (IS_ERR(inode)) {
503 ret = PTR_ERR(inode);
504 goto fail;
505 }
506 BUG_ON(!inode);
507 d_instantiate(dentry, inode);
508 ret = 0;
509fail:
510 kfree(pending_snapshot);
511 return ret;
512}
513
514/* copy of check_sticky in fs/namei.c()
515* It's inline, so penalty for filesystems that don't use sticky bit is
516* minimal.
517*/
518static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
519{
520 uid_t fsuid = current_fsuid();
521
522 if (!(dir->i_mode & S_ISVTX))
523 return 0;
524 if (inode->i_uid == fsuid)
525 return 0;
526 if (dir->i_uid == fsuid)
527 return 0;
528 return !capable(CAP_FOWNER);
529}
530
531/* copy of may_delete in fs/namei.c()
532 * Check whether we can remove a link victim from directory dir, check
533 * whether the type of victim is right.
534 * 1. We can't do it if dir is read-only (done in permission())
535 * 2. We should have write and exec permissions on dir
536 * 3. We can't remove anything from append-only dir
537 * 4. We can't do anything with immutable dir (done in permission())
538 * 5. If the sticky bit on dir is set we should either
539 * a. be owner of dir, or
540 * b. be owner of victim, or
541 * c. have CAP_FOWNER capability
542 * 6. If the victim is append-only or immutable we can't do antyhing with
543 * links pointing to it.
544 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
545 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
546 * 9. We can't remove a root or mountpoint.
547 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
548 * nfs_async_unlink().
549 */
550
551static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
552{
553 int error;
554
555 if (!victim->d_inode)
556 return -ENOENT;
557
558 BUG_ON(victim->d_parent->d_inode != dir);
559 audit_inode_child(victim, dir);
560
561 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
562 if (error)
563 return error;
564 if (IS_APPEND(dir))
565 return -EPERM;
566 if (btrfs_check_sticky(dir, victim->d_inode)||
567 IS_APPEND(victim->d_inode)||
568 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
569 return -EPERM;
570 if (isdir) {
571 if (!S_ISDIR(victim->d_inode->i_mode))
572 return -ENOTDIR;
573 if (IS_ROOT(victim))
574 return -EBUSY;
575 } else if (S_ISDIR(victim->d_inode->i_mode))
576 return -EISDIR;
577 if (IS_DEADDIR(dir))
578 return -ENOENT;
579 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
580 return -EBUSY;
581 return 0;
582}
583
584/* copy of may_create in fs/namei.c() */
585static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
586{
587 if (child->d_inode)
588 return -EEXIST;
589 if (IS_DEADDIR(dir))
590 return -ENOENT;
591 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
592}
593
594/*
595 * Create a new subvolume below @parent. This is largely modeled after
596 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
597 * inside this filesystem so it's quite a bit simpler.
598 */
599static noinline int btrfs_mksubvol(struct path *parent,
600 char *name, int namelen,
601 struct btrfs_root *snap_src,
602 u64 *async_transid, bool readonly)
603{
604 struct inode *dir = parent->dentry->d_inode;
605 struct dentry *dentry;
606 int error;
607
608 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
609
610 dentry = lookup_one_len(name, parent->dentry, namelen);
611 error = PTR_ERR(dentry);
612 if (IS_ERR(dentry))
613 goto out_unlock;
614
615 error = -EEXIST;
616 if (dentry->d_inode)
617 goto out_dput;
618
619 error = mnt_want_write(parent->mnt);
620 if (error)
621 goto out_dput;
622
623 error = btrfs_may_create(dir, dentry);
624 if (error)
625 goto out_drop_write;
626
627 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
628
629 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
630 goto out_up_read;
631
632 if (snap_src) {
633 error = create_snapshot(snap_src, dentry,
634 name, namelen, async_transid, readonly);
635 } else {
636 error = create_subvol(BTRFS_I(dir)->root, dentry,
637 name, namelen, async_transid);
638 }
639 if (!error)
640 fsnotify_mkdir(dir, dentry);
641out_up_read:
642 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
643out_drop_write:
644 mnt_drop_write(parent->mnt);
645out_dput:
646 dput(dentry);
647out_unlock:
648 mutex_unlock(&dir->i_mutex);
649 return error;
650}
651
652/*
653 * When we're defragging a range, we don't want to kick it off again
654 * if it is really just waiting for delalloc to send it down.
655 * If we find a nice big extent or delalloc range for the bytes in the
656 * file you want to defrag, we return 0 to let you know to skip this
657 * part of the file
658 */
659static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
660{
661 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
662 struct extent_map *em = NULL;
663 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
664 u64 end;
665
666 read_lock(&em_tree->lock);
667 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
668 read_unlock(&em_tree->lock);
669
670 if (em) {
671 end = extent_map_end(em);
672 free_extent_map(em);
673 if (end - offset > thresh)
674 return 0;
675 }
676 /* if we already have a nice delalloc here, just stop */
677 thresh /= 2;
678 end = count_range_bits(io_tree, &offset, offset + thresh,
679 thresh, EXTENT_DELALLOC, 1);
680 if (end >= thresh)
681 return 0;
682 return 1;
683}
684
685/*
686 * helper function to walk through a file and find extents
687 * newer than a specific transid, and smaller than thresh.
688 *
689 * This is used by the defragging code to find new and small
690 * extents
691 */
692static int find_new_extents(struct btrfs_root *root,
693 struct inode *inode, u64 newer_than,
694 u64 *off, int thresh)
695{
696 struct btrfs_path *path;
697 struct btrfs_key min_key;
698 struct btrfs_key max_key;
699 struct extent_buffer *leaf;
700 struct btrfs_file_extent_item *extent;
701 int type;
702 int ret;
703 u64 ino = btrfs_ino(inode);
704
705 path = btrfs_alloc_path();
706 if (!path)
707 return -ENOMEM;
708
709 min_key.objectid = ino;
710 min_key.type = BTRFS_EXTENT_DATA_KEY;
711 min_key.offset = *off;
712
713 max_key.objectid = ino;
714 max_key.type = (u8)-1;
715 max_key.offset = (u64)-1;
716
717 path->keep_locks = 1;
718
719 while(1) {
720 ret = btrfs_search_forward(root, &min_key, &max_key,
721 path, 0, newer_than);
722 if (ret != 0)
723 goto none;
724 if (min_key.objectid != ino)
725 goto none;
726 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
727 goto none;
728
729 leaf = path->nodes[0];
730 extent = btrfs_item_ptr(leaf, path->slots[0],
731 struct btrfs_file_extent_item);
732
733 type = btrfs_file_extent_type(leaf, extent);
734 if (type == BTRFS_FILE_EXTENT_REG &&
735 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
736 check_defrag_in_cache(inode, min_key.offset, thresh)) {
737 *off = min_key.offset;
738 btrfs_free_path(path);
739 return 0;
740 }
741
742 if (min_key.offset == (u64)-1)
743 goto none;
744
745 min_key.offset++;
746 btrfs_release_path(path);
747 }
748none:
749 btrfs_free_path(path);
750 return -ENOENT;
751}
752
753static int should_defrag_range(struct inode *inode, u64 start, u64 len,
754 int thresh, u64 *last_len, u64 *skip,
755 u64 *defrag_end)
756{
757 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
758 struct extent_map *em = NULL;
759 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
760 int ret = 1;
761
762 /*
763 * make sure that once we start defragging and extent, we keep on
764 * defragging it
765 */
766 if (start < *defrag_end)
767 return 1;
768
769 *skip = 0;
770
771 /*
772 * hopefully we have this extent in the tree already, try without
773 * the full extent lock
774 */
775 read_lock(&em_tree->lock);
776 em = lookup_extent_mapping(em_tree, start, len);
777 read_unlock(&em_tree->lock);
778
779 if (!em) {
780 /* get the big lock and read metadata off disk */
781 lock_extent(io_tree, start, start + len - 1, GFP_NOFS);
782 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
783 unlock_extent(io_tree, start, start + len - 1, GFP_NOFS);
784
785 if (IS_ERR(em))
786 return 0;
787 }
788
789 /* this will cover holes, and inline extents */
790 if (em->block_start >= EXTENT_MAP_LAST_BYTE)
791 ret = 0;
792
793 /*
794 * we hit a real extent, if it is big don't bother defragging it again
795 */
796 if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
797 ret = 0;
798
799 /*
800 * last_len ends up being a counter of how many bytes we've defragged.
801 * every time we choose not to defrag an extent, we reset *last_len
802 * so that the next tiny extent will force a defrag.
803 *
804 * The end result of this is that tiny extents before a single big
805 * extent will force at least part of that big extent to be defragged.
806 */
807 if (ret) {
808 *last_len += len;
809 *defrag_end = extent_map_end(em);
810 } else {
811 *last_len = 0;
812 *skip = extent_map_end(em);
813 *defrag_end = 0;
814 }
815
816 free_extent_map(em);
817 return ret;
818}
819
820/*
821 * it doesn't do much good to defrag one or two pages
822 * at a time. This pulls in a nice chunk of pages
823 * to COW and defrag.
824 *
825 * It also makes sure the delalloc code has enough
826 * dirty data to avoid making new small extents as part
827 * of the defrag
828 *
829 * It's a good idea to start RA on this range
830 * before calling this.
831 */
832static int cluster_pages_for_defrag(struct inode *inode,
833 struct page **pages,
834 unsigned long start_index,
835 int num_pages)
836{
837 unsigned long file_end;
838 u64 isize = i_size_read(inode);
839 u64 page_start;
840 u64 page_end;
841 int ret;
842 int i;
843 int i_done;
844 struct btrfs_ordered_extent *ordered;
845 struct extent_state *cached_state = NULL;
846
847 if (isize == 0)
848 return 0;
849 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
850
851 ret = btrfs_delalloc_reserve_space(inode,
852 num_pages << PAGE_CACHE_SHIFT);
853 if (ret)
854 return ret;
855again:
856 ret = 0;
857 i_done = 0;
858
859 /* step one, lock all the pages */
860 for (i = 0; i < num_pages; i++) {
861 struct page *page;
862 page = find_or_create_page(inode->i_mapping,
863 start_index + i, GFP_NOFS);
864 if (!page)
865 break;
866
867 if (!PageUptodate(page)) {
868 btrfs_readpage(NULL, page);
869 lock_page(page);
870 if (!PageUptodate(page)) {
871 unlock_page(page);
872 page_cache_release(page);
873 ret = -EIO;
874 break;
875 }
876 }
877 isize = i_size_read(inode);
878 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
879 if (!isize || page->index > file_end ||
880 page->mapping != inode->i_mapping) {
881 /* whoops, we blew past eof, skip this page */
882 unlock_page(page);
883 page_cache_release(page);
884 break;
885 }
886 pages[i] = page;
887 i_done++;
888 }
889 if (!i_done || ret)
890 goto out;
891
892 if (!(inode->i_sb->s_flags & MS_ACTIVE))
893 goto out;
894
895 /*
896 * so now we have a nice long stream of locked
897 * and up to date pages, lets wait on them
898 */
899 for (i = 0; i < i_done; i++)
900 wait_on_page_writeback(pages[i]);
901
902 page_start = page_offset(pages[0]);
903 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
904
905 lock_extent_bits(&BTRFS_I(inode)->io_tree,
906 page_start, page_end - 1, 0, &cached_state,
907 GFP_NOFS);
908 ordered = btrfs_lookup_first_ordered_extent(inode, page_end - 1);
909 if (ordered &&
910 ordered->file_offset + ordered->len > page_start &&
911 ordered->file_offset < page_end) {
912 btrfs_put_ordered_extent(ordered);
913 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
914 page_start, page_end - 1,
915 &cached_state, GFP_NOFS);
916 for (i = 0; i < i_done; i++) {
917 unlock_page(pages[i]);
918 page_cache_release(pages[i]);
919 }
920 btrfs_wait_ordered_range(inode, page_start,
921 page_end - page_start);
922 goto again;
923 }
924 if (ordered)
925 btrfs_put_ordered_extent(ordered);
926
927 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
928 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
929 EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
930 GFP_NOFS);
931
932 if (i_done != num_pages) {
933 spin_lock(&BTRFS_I(inode)->lock);
934 BTRFS_I(inode)->outstanding_extents++;
935 spin_unlock(&BTRFS_I(inode)->lock);
936 btrfs_delalloc_release_space(inode,
937 (num_pages - i_done) << PAGE_CACHE_SHIFT);
938 }
939
940
941 btrfs_set_extent_delalloc(inode, page_start, page_end - 1,
942 &cached_state);
943
944 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
945 page_start, page_end - 1, &cached_state,
946 GFP_NOFS);
947
948 for (i = 0; i < i_done; i++) {
949 clear_page_dirty_for_io(pages[i]);
950 ClearPageChecked(pages[i]);
951 set_page_extent_mapped(pages[i]);
952 set_page_dirty(pages[i]);
953 unlock_page(pages[i]);
954 page_cache_release(pages[i]);
955 }
956 return i_done;
957out:
958 for (i = 0; i < i_done; i++) {
959 unlock_page(pages[i]);
960 page_cache_release(pages[i]);
961 }
962 btrfs_delalloc_release_space(inode, num_pages << PAGE_CACHE_SHIFT);
963 return ret;
964
965}
966
967int btrfs_defrag_file(struct inode *inode, struct file *file,
968 struct btrfs_ioctl_defrag_range_args *range,
969 u64 newer_than, unsigned long max_to_defrag)
970{
971 struct btrfs_root *root = BTRFS_I(inode)->root;
972 struct btrfs_super_block *disk_super;
973 struct file_ra_state *ra = NULL;
974 unsigned long last_index;
975 u64 features;
976 u64 last_len = 0;
977 u64 skip = 0;
978 u64 defrag_end = 0;
979 u64 newer_off = range->start;
980 int newer_left = 0;
981 unsigned long i;
982 int ret;
983 int defrag_count = 0;
984 int compress_type = BTRFS_COMPRESS_ZLIB;
985 int extent_thresh = range->extent_thresh;
986 int newer_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
987 u64 new_align = ~((u64)128 * 1024 - 1);
988 struct page **pages = NULL;
989
990 if (extent_thresh == 0)
991 extent_thresh = 256 * 1024;
992
993 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
994 if (range->compress_type > BTRFS_COMPRESS_TYPES)
995 return -EINVAL;
996 if (range->compress_type)
997 compress_type = range->compress_type;
998 }
999
1000 if (inode->i_size == 0)
1001 return 0;
1002
1003 /*
1004 * if we were not given a file, allocate a readahead
1005 * context
1006 */
1007 if (!file) {
1008 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1009 if (!ra)
1010 return -ENOMEM;
1011 file_ra_state_init(ra, inode->i_mapping);
1012 } else {
1013 ra = &file->f_ra;
1014 }
1015
1016 pages = kmalloc(sizeof(struct page *) * newer_cluster,
1017 GFP_NOFS);
1018 if (!pages) {
1019 ret = -ENOMEM;
1020 goto out_ra;
1021 }
1022
1023 /* find the last page to defrag */
1024 if (range->start + range->len > range->start) {
1025 last_index = min_t(u64, inode->i_size - 1,
1026 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1027 } else {
1028 last_index = (inode->i_size - 1) >> PAGE_CACHE_SHIFT;
1029 }
1030
1031 if (newer_than) {
1032 ret = find_new_extents(root, inode, newer_than,
1033 &newer_off, 64 * 1024);
1034 if (!ret) {
1035 range->start = newer_off;
1036 /*
1037 * we always align our defrag to help keep
1038 * the extents in the file evenly spaced
1039 */
1040 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1041 newer_left = newer_cluster;
1042 } else
1043 goto out_ra;
1044 } else {
1045 i = range->start >> PAGE_CACHE_SHIFT;
1046 }
1047 if (!max_to_defrag)
1048 max_to_defrag = last_index - 1;
1049
1050 /*
1051 * make writeback starts from i, so the defrag range can be
1052 * written sequentially.
1053 */
1054 if (i < inode->i_mapping->writeback_index)
1055 inode->i_mapping->writeback_index = i;
1056
1057 while (i <= last_index && defrag_count < max_to_defrag &&
1058 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1059 PAGE_CACHE_SHIFT)) {
1060 /*
1061 * make sure we stop running if someone unmounts
1062 * the FS
1063 */
1064 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1065 break;
1066
1067 if (!newer_than &&
1068 !should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1069 PAGE_CACHE_SIZE,
1070 extent_thresh,
1071 &last_len, &skip,
1072 &defrag_end)) {
1073 unsigned long next;
1074 /*
1075 * the should_defrag function tells us how much to skip
1076 * bump our counter by the suggested amount
1077 */
1078 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1079 i = max(i + 1, next);
1080 continue;
1081 }
1082 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1083 BTRFS_I(inode)->force_compress = compress_type;
1084
1085 btrfs_force_ra(inode->i_mapping, ra, file, i, newer_cluster);
1086
1087 ret = cluster_pages_for_defrag(inode, pages, i, newer_cluster);
1088 if (ret < 0)
1089 goto out_ra;
1090
1091 defrag_count += ret;
1092 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
1093 i += ret;
1094
1095 if (newer_than) {
1096 if (newer_off == (u64)-1)
1097 break;
1098
1099 newer_off = max(newer_off + 1,
1100 (u64)i << PAGE_CACHE_SHIFT);
1101
1102 ret = find_new_extents(root, inode,
1103 newer_than, &newer_off,
1104 64 * 1024);
1105 if (!ret) {
1106 range->start = newer_off;
1107 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1108 newer_left = newer_cluster;
1109 } else {
1110 break;
1111 }
1112 } else {
1113 i++;
1114 }
1115 }
1116
1117 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1118 filemap_flush(inode->i_mapping);
1119
1120 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1121 /* the filemap_flush will queue IO into the worker threads, but
1122 * we have to make sure the IO is actually started and that
1123 * ordered extents get created before we return
1124 */
1125 atomic_inc(&root->fs_info->async_submit_draining);
1126 while (atomic_read(&root->fs_info->nr_async_submits) ||
1127 atomic_read(&root->fs_info->async_delalloc_pages)) {
1128 wait_event(root->fs_info->async_submit_wait,
1129 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1130 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1131 }
1132 atomic_dec(&root->fs_info->async_submit_draining);
1133
1134 mutex_lock(&inode->i_mutex);
1135 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1136 mutex_unlock(&inode->i_mutex);
1137 }
1138
1139 disk_super = &root->fs_info->super_copy;
1140 features = btrfs_super_incompat_flags(disk_super);
1141 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1142 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
1143 btrfs_set_super_incompat_flags(disk_super, features);
1144 }
1145
1146 if (!file)
1147 kfree(ra);
1148 return defrag_count;
1149
1150out_ra:
1151 if (!file)
1152 kfree(ra);
1153 kfree(pages);
1154 return ret;
1155}
1156
1157static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
1158 void __user *arg)
1159{
1160 u64 new_size;
1161 u64 old_size;
1162 u64 devid = 1;
1163 struct btrfs_ioctl_vol_args *vol_args;
1164 struct btrfs_trans_handle *trans;
1165 struct btrfs_device *device = NULL;
1166 char *sizestr;
1167 char *devstr = NULL;
1168 int ret = 0;
1169 int mod = 0;
1170
1171 if (root->fs_info->sb->s_flags & MS_RDONLY)
1172 return -EROFS;
1173
1174 if (!capable(CAP_SYS_ADMIN))
1175 return -EPERM;
1176
1177 vol_args = memdup_user(arg, sizeof(*vol_args));
1178 if (IS_ERR(vol_args))
1179 return PTR_ERR(vol_args);
1180
1181 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1182
1183 mutex_lock(&root->fs_info->volume_mutex);
1184 sizestr = vol_args->name;
1185 devstr = strchr(sizestr, ':');
1186 if (devstr) {
1187 char *end;
1188 sizestr = devstr + 1;
1189 *devstr = '\0';
1190 devstr = vol_args->name;
1191 devid = simple_strtoull(devstr, &end, 10);
1192 printk(KERN_INFO "resizing devid %llu\n",
1193 (unsigned long long)devid);
1194 }
1195 device = btrfs_find_device(root, devid, NULL, NULL);
1196 if (!device) {
1197 printk(KERN_INFO "resizer unable to find device %llu\n",
1198 (unsigned long long)devid);
1199 ret = -EINVAL;
1200 goto out_unlock;
1201 }
1202 if (!strcmp(sizestr, "max"))
1203 new_size = device->bdev->bd_inode->i_size;
1204 else {
1205 if (sizestr[0] == '-') {
1206 mod = -1;
1207 sizestr++;
1208 } else if (sizestr[0] == '+') {
1209 mod = 1;
1210 sizestr++;
1211 }
1212 new_size = memparse(sizestr, NULL);
1213 if (new_size == 0) {
1214 ret = -EINVAL;
1215 goto out_unlock;
1216 }
1217 }
1218
1219 old_size = device->total_bytes;
1220
1221 if (mod < 0) {
1222 if (new_size > old_size) {
1223 ret = -EINVAL;
1224 goto out_unlock;
1225 }
1226 new_size = old_size - new_size;
1227 } else if (mod > 0) {
1228 new_size = old_size + new_size;
1229 }
1230
1231 if (new_size < 256 * 1024 * 1024) {
1232 ret = -EINVAL;
1233 goto out_unlock;
1234 }
1235 if (new_size > device->bdev->bd_inode->i_size) {
1236 ret = -EFBIG;
1237 goto out_unlock;
1238 }
1239
1240 do_div(new_size, root->sectorsize);
1241 new_size *= root->sectorsize;
1242
1243 printk(KERN_INFO "new size for %s is %llu\n",
1244 device->name, (unsigned long long)new_size);
1245
1246 if (new_size > old_size) {
1247 trans = btrfs_start_transaction(root, 0);
1248 if (IS_ERR(trans)) {
1249 ret = PTR_ERR(trans);
1250 goto out_unlock;
1251 }
1252 ret = btrfs_grow_device(trans, device, new_size);
1253 btrfs_commit_transaction(trans, root);
1254 } else {
1255 ret = btrfs_shrink_device(device, new_size);
1256 }
1257
1258out_unlock:
1259 mutex_unlock(&root->fs_info->volume_mutex);
1260 kfree(vol_args);
1261 return ret;
1262}
1263
1264static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1265 char *name,
1266 unsigned long fd,
1267 int subvol,
1268 u64 *transid,
1269 bool readonly)
1270{
1271 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1272 struct file *src_file;
1273 int namelen;
1274 int ret = 0;
1275
1276 if (root->fs_info->sb->s_flags & MS_RDONLY)
1277 return -EROFS;
1278
1279 namelen = strlen(name);
1280 if (strchr(name, '/')) {
1281 ret = -EINVAL;
1282 goto out;
1283 }
1284
1285 if (subvol) {
1286 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1287 NULL, transid, readonly);
1288 } else {
1289 struct inode *src_inode;
1290 src_file = fget(fd);
1291 if (!src_file) {
1292 ret = -EINVAL;
1293 goto out;
1294 }
1295
1296 src_inode = src_file->f_path.dentry->d_inode;
1297 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1298 printk(KERN_INFO "btrfs: Snapshot src from "
1299 "another FS\n");
1300 ret = -EINVAL;
1301 fput(src_file);
1302 goto out;
1303 }
1304 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1305 BTRFS_I(src_inode)->root,
1306 transid, readonly);
1307 fput(src_file);
1308 }
1309out:
1310 return ret;
1311}
1312
1313static noinline int btrfs_ioctl_snap_create(struct file *file,
1314 void __user *arg, int subvol)
1315{
1316 struct btrfs_ioctl_vol_args *vol_args;
1317 int ret;
1318
1319 vol_args = memdup_user(arg, sizeof(*vol_args));
1320 if (IS_ERR(vol_args))
1321 return PTR_ERR(vol_args);
1322 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1323
1324 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1325 vol_args->fd, subvol,
1326 NULL, false);
1327
1328 kfree(vol_args);
1329 return ret;
1330}
1331
1332static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1333 void __user *arg, int subvol)
1334{
1335 struct btrfs_ioctl_vol_args_v2 *vol_args;
1336 int ret;
1337 u64 transid = 0;
1338 u64 *ptr = NULL;
1339 bool readonly = false;
1340
1341 vol_args = memdup_user(arg, sizeof(*vol_args));
1342 if (IS_ERR(vol_args))
1343 return PTR_ERR(vol_args);
1344 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1345
1346 if (vol_args->flags &
1347 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
1348 ret = -EOPNOTSUPP;
1349 goto out;
1350 }
1351
1352 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1353 ptr = &transid;
1354 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1355 readonly = true;
1356
1357 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1358 vol_args->fd, subvol,
1359 ptr, readonly);
1360
1361 if (ret == 0 && ptr &&
1362 copy_to_user(arg +
1363 offsetof(struct btrfs_ioctl_vol_args_v2,
1364 transid), ptr, sizeof(*ptr)))
1365 ret = -EFAULT;
1366out:
1367 kfree(vol_args);
1368 return ret;
1369}
1370
1371static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1372 void __user *arg)
1373{
1374 struct inode *inode = fdentry(file)->d_inode;
1375 struct btrfs_root *root = BTRFS_I(inode)->root;
1376 int ret = 0;
1377 u64 flags = 0;
1378
1379 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1380 return -EINVAL;
1381
1382 down_read(&root->fs_info->subvol_sem);
1383 if (btrfs_root_readonly(root))
1384 flags |= BTRFS_SUBVOL_RDONLY;
1385 up_read(&root->fs_info->subvol_sem);
1386
1387 if (copy_to_user(arg, &flags, sizeof(flags)))
1388 ret = -EFAULT;
1389
1390 return ret;
1391}
1392
1393static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1394 void __user *arg)
1395{
1396 struct inode *inode = fdentry(file)->d_inode;
1397 struct btrfs_root *root = BTRFS_I(inode)->root;
1398 struct btrfs_trans_handle *trans;
1399 u64 root_flags;
1400 u64 flags;
1401 int ret = 0;
1402
1403 if (root->fs_info->sb->s_flags & MS_RDONLY)
1404 return -EROFS;
1405
1406 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1407 return -EINVAL;
1408
1409 if (copy_from_user(&flags, arg, sizeof(flags)))
1410 return -EFAULT;
1411
1412 if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
1413 return -EINVAL;
1414
1415 if (flags & ~BTRFS_SUBVOL_RDONLY)
1416 return -EOPNOTSUPP;
1417
1418 if (!inode_owner_or_capable(inode))
1419 return -EACCES;
1420
1421 down_write(&root->fs_info->subvol_sem);
1422
1423 /* nothing to do */
1424 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1425 goto out;
1426
1427 root_flags = btrfs_root_flags(&root->root_item);
1428 if (flags & BTRFS_SUBVOL_RDONLY)
1429 btrfs_set_root_flags(&root->root_item,
1430 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1431 else
1432 btrfs_set_root_flags(&root->root_item,
1433 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1434
1435 trans = btrfs_start_transaction(root, 1);
1436 if (IS_ERR(trans)) {
1437 ret = PTR_ERR(trans);
1438 goto out_reset;
1439 }
1440
1441 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1442 &root->root_key, &root->root_item);
1443
1444 btrfs_commit_transaction(trans, root);
1445out_reset:
1446 if (ret)
1447 btrfs_set_root_flags(&root->root_item, root_flags);
1448out:
1449 up_write(&root->fs_info->subvol_sem);
1450 return ret;
1451}
1452
1453/*
1454 * helper to check if the subvolume references other subvolumes
1455 */
1456static noinline int may_destroy_subvol(struct btrfs_root *root)
1457{
1458 struct btrfs_path *path;
1459 struct btrfs_key key;
1460 int ret;
1461
1462 path = btrfs_alloc_path();
1463 if (!path)
1464 return -ENOMEM;
1465
1466 key.objectid = root->root_key.objectid;
1467 key.type = BTRFS_ROOT_REF_KEY;
1468 key.offset = (u64)-1;
1469
1470 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1471 &key, path, 0, 0);
1472 if (ret < 0)
1473 goto out;
1474 BUG_ON(ret == 0);
1475
1476 ret = 0;
1477 if (path->slots[0] > 0) {
1478 path->slots[0]--;
1479 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1480 if (key.objectid == root->root_key.objectid &&
1481 key.type == BTRFS_ROOT_REF_KEY)
1482 ret = -ENOTEMPTY;
1483 }
1484out:
1485 btrfs_free_path(path);
1486 return ret;
1487}
1488
1489static noinline int key_in_sk(struct btrfs_key *key,
1490 struct btrfs_ioctl_search_key *sk)
1491{
1492 struct btrfs_key test;
1493 int ret;
1494
1495 test.objectid = sk->min_objectid;
1496 test.type = sk->min_type;
1497 test.offset = sk->min_offset;
1498
1499 ret = btrfs_comp_cpu_keys(key, &test);
1500 if (ret < 0)
1501 return 0;
1502
1503 test.objectid = sk->max_objectid;
1504 test.type = sk->max_type;
1505 test.offset = sk->max_offset;
1506
1507 ret = btrfs_comp_cpu_keys(key, &test);
1508 if (ret > 0)
1509 return 0;
1510 return 1;
1511}
1512
1513static noinline int copy_to_sk(struct btrfs_root *root,
1514 struct btrfs_path *path,
1515 struct btrfs_key *key,
1516 struct btrfs_ioctl_search_key *sk,
1517 char *buf,
1518 unsigned long *sk_offset,
1519 int *num_found)
1520{
1521 u64 found_transid;
1522 struct extent_buffer *leaf;
1523 struct btrfs_ioctl_search_header sh;
1524 unsigned long item_off;
1525 unsigned long item_len;
1526 int nritems;
1527 int i;
1528 int slot;
1529 int ret = 0;
1530
1531 leaf = path->nodes[0];
1532 slot = path->slots[0];
1533 nritems = btrfs_header_nritems(leaf);
1534
1535 if (btrfs_header_generation(leaf) > sk->max_transid) {
1536 i = nritems;
1537 goto advance_key;
1538 }
1539 found_transid = btrfs_header_generation(leaf);
1540
1541 for (i = slot; i < nritems; i++) {
1542 item_off = btrfs_item_ptr_offset(leaf, i);
1543 item_len = btrfs_item_size_nr(leaf, i);
1544
1545 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1546 item_len = 0;
1547
1548 if (sizeof(sh) + item_len + *sk_offset >
1549 BTRFS_SEARCH_ARGS_BUFSIZE) {
1550 ret = 1;
1551 goto overflow;
1552 }
1553
1554 btrfs_item_key_to_cpu(leaf, key, i);
1555 if (!key_in_sk(key, sk))
1556 continue;
1557
1558 sh.objectid = key->objectid;
1559 sh.offset = key->offset;
1560 sh.type = key->type;
1561 sh.len = item_len;
1562 sh.transid = found_transid;
1563
1564 /* copy search result header */
1565 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1566 *sk_offset += sizeof(sh);
1567
1568 if (item_len) {
1569 char *p = buf + *sk_offset;
1570 /* copy the item */
1571 read_extent_buffer(leaf, p,
1572 item_off, item_len);
1573 *sk_offset += item_len;
1574 }
1575 (*num_found)++;
1576
1577 if (*num_found >= sk->nr_items)
1578 break;
1579 }
1580advance_key:
1581 ret = 0;
1582 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1583 key->offset++;
1584 else if (key->type < (u8)-1 && key->type < sk->max_type) {
1585 key->offset = 0;
1586 key->type++;
1587 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1588 key->offset = 0;
1589 key->type = 0;
1590 key->objectid++;
1591 } else
1592 ret = 1;
1593overflow:
1594 return ret;
1595}
1596
1597static noinline int search_ioctl(struct inode *inode,
1598 struct btrfs_ioctl_search_args *args)
1599{
1600 struct btrfs_root *root;
1601 struct btrfs_key key;
1602 struct btrfs_key max_key;
1603 struct btrfs_path *path;
1604 struct btrfs_ioctl_search_key *sk = &args->key;
1605 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1606 int ret;
1607 int num_found = 0;
1608 unsigned long sk_offset = 0;
1609
1610 path = btrfs_alloc_path();
1611 if (!path)
1612 return -ENOMEM;
1613
1614 if (sk->tree_id == 0) {
1615 /* search the root of the inode that was passed */
1616 root = BTRFS_I(inode)->root;
1617 } else {
1618 key.objectid = sk->tree_id;
1619 key.type = BTRFS_ROOT_ITEM_KEY;
1620 key.offset = (u64)-1;
1621 root = btrfs_read_fs_root_no_name(info, &key);
1622 if (IS_ERR(root)) {
1623 printk(KERN_ERR "could not find root %llu\n",
1624 sk->tree_id);
1625 btrfs_free_path(path);
1626 return -ENOENT;
1627 }
1628 }
1629
1630 key.objectid = sk->min_objectid;
1631 key.type = sk->min_type;
1632 key.offset = sk->min_offset;
1633
1634 max_key.objectid = sk->max_objectid;
1635 max_key.type = sk->max_type;
1636 max_key.offset = sk->max_offset;
1637
1638 path->keep_locks = 1;
1639
1640 while(1) {
1641 ret = btrfs_search_forward(root, &key, &max_key, path, 0,
1642 sk->min_transid);
1643 if (ret != 0) {
1644 if (ret > 0)
1645 ret = 0;
1646 goto err;
1647 }
1648 ret = copy_to_sk(root, path, &key, sk, args->buf,
1649 &sk_offset, &num_found);
1650 btrfs_release_path(path);
1651 if (ret || num_found >= sk->nr_items)
1652 break;
1653
1654 }
1655 ret = 0;
1656err:
1657 sk->nr_items = num_found;
1658 btrfs_free_path(path);
1659 return ret;
1660}
1661
1662static noinline int btrfs_ioctl_tree_search(struct file *file,
1663 void __user *argp)
1664{
1665 struct btrfs_ioctl_search_args *args;
1666 struct inode *inode;
1667 int ret;
1668
1669 if (!capable(CAP_SYS_ADMIN))
1670 return -EPERM;
1671
1672 args = memdup_user(argp, sizeof(*args));
1673 if (IS_ERR(args))
1674 return PTR_ERR(args);
1675
1676 inode = fdentry(file)->d_inode;
1677 ret = search_ioctl(inode, args);
1678 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1679 ret = -EFAULT;
1680 kfree(args);
1681 return ret;
1682}
1683
1684/*
1685 * Search INODE_REFs to identify path name of 'dirid' directory
1686 * in a 'tree_id' tree. and sets path name to 'name'.
1687 */
1688static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1689 u64 tree_id, u64 dirid, char *name)
1690{
1691 struct btrfs_root *root;
1692 struct btrfs_key key;
1693 char *ptr;
1694 int ret = -1;
1695 int slot;
1696 int len;
1697 int total_len = 0;
1698 struct btrfs_inode_ref *iref;
1699 struct extent_buffer *l;
1700 struct btrfs_path *path;
1701
1702 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1703 name[0]='\0';
1704 return 0;
1705 }
1706
1707 path = btrfs_alloc_path();
1708 if (!path)
1709 return -ENOMEM;
1710
1711 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1712
1713 key.objectid = tree_id;
1714 key.type = BTRFS_ROOT_ITEM_KEY;
1715 key.offset = (u64)-1;
1716 root = btrfs_read_fs_root_no_name(info, &key);
1717 if (IS_ERR(root)) {
1718 printk(KERN_ERR "could not find root %llu\n", tree_id);
1719 ret = -ENOENT;
1720 goto out;
1721 }
1722
1723 key.objectid = dirid;
1724 key.type = BTRFS_INODE_REF_KEY;
1725 key.offset = (u64)-1;
1726
1727 while(1) {
1728 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1729 if (ret < 0)
1730 goto out;
1731
1732 l = path->nodes[0];
1733 slot = path->slots[0];
1734 if (ret > 0 && slot > 0)
1735 slot--;
1736 btrfs_item_key_to_cpu(l, &key, slot);
1737
1738 if (ret > 0 && (key.objectid != dirid ||
1739 key.type != BTRFS_INODE_REF_KEY)) {
1740 ret = -ENOENT;
1741 goto out;
1742 }
1743
1744 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1745 len = btrfs_inode_ref_name_len(l, iref);
1746 ptr -= len + 1;
1747 total_len += len + 1;
1748 if (ptr < name)
1749 goto out;
1750
1751 *(ptr + len) = '/';
1752 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1753
1754 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1755 break;
1756
1757 btrfs_release_path(path);
1758 key.objectid = key.offset;
1759 key.offset = (u64)-1;
1760 dirid = key.objectid;
1761 }
1762 if (ptr < name)
1763 goto out;
1764 memmove(name, ptr, total_len);
1765 name[total_len]='\0';
1766 ret = 0;
1767out:
1768 btrfs_free_path(path);
1769 return ret;
1770}
1771
1772static noinline int btrfs_ioctl_ino_lookup(struct file *file,
1773 void __user *argp)
1774{
1775 struct btrfs_ioctl_ino_lookup_args *args;
1776 struct inode *inode;
1777 int ret;
1778
1779 if (!capable(CAP_SYS_ADMIN))
1780 return -EPERM;
1781
1782 args = memdup_user(argp, sizeof(*args));
1783 if (IS_ERR(args))
1784 return PTR_ERR(args);
1785
1786 inode = fdentry(file)->d_inode;
1787
1788 if (args->treeid == 0)
1789 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
1790
1791 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
1792 args->treeid, args->objectid,
1793 args->name);
1794
1795 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1796 ret = -EFAULT;
1797
1798 kfree(args);
1799 return ret;
1800}
1801
1802static noinline int btrfs_ioctl_snap_destroy(struct file *file,
1803 void __user *arg)
1804{
1805 struct dentry *parent = fdentry(file);
1806 struct dentry *dentry;
1807 struct inode *dir = parent->d_inode;
1808 struct inode *inode;
1809 struct btrfs_root *root = BTRFS_I(dir)->root;
1810 struct btrfs_root *dest = NULL;
1811 struct btrfs_ioctl_vol_args *vol_args;
1812 struct btrfs_trans_handle *trans;
1813 int namelen;
1814 int ret;
1815 int err = 0;
1816
1817 vol_args = memdup_user(arg, sizeof(*vol_args));
1818 if (IS_ERR(vol_args))
1819 return PTR_ERR(vol_args);
1820
1821 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1822 namelen = strlen(vol_args->name);
1823 if (strchr(vol_args->name, '/') ||
1824 strncmp(vol_args->name, "..", namelen) == 0) {
1825 err = -EINVAL;
1826 goto out;
1827 }
1828
1829 err = mnt_want_write(file->f_path.mnt);
1830 if (err)
1831 goto out;
1832
1833 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
1834 dentry = lookup_one_len(vol_args->name, parent, namelen);
1835 if (IS_ERR(dentry)) {
1836 err = PTR_ERR(dentry);
1837 goto out_unlock_dir;
1838 }
1839
1840 if (!dentry->d_inode) {
1841 err = -ENOENT;
1842 goto out_dput;
1843 }
1844
1845 inode = dentry->d_inode;
1846 dest = BTRFS_I(inode)->root;
1847 if (!capable(CAP_SYS_ADMIN)){
1848 /*
1849 * Regular user. Only allow this with a special mount
1850 * option, when the user has write+exec access to the
1851 * subvol root, and when rmdir(2) would have been
1852 * allowed.
1853 *
1854 * Note that this is _not_ check that the subvol is
1855 * empty or doesn't contain data that we wouldn't
1856 * otherwise be able to delete.
1857 *
1858 * Users who want to delete empty subvols should try
1859 * rmdir(2).
1860 */
1861 err = -EPERM;
1862 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
1863 goto out_dput;
1864
1865 /*
1866 * Do not allow deletion if the parent dir is the same
1867 * as the dir to be deleted. That means the ioctl
1868 * must be called on the dentry referencing the root
1869 * of the subvol, not a random directory contained
1870 * within it.
1871 */
1872 err = -EINVAL;
1873 if (root == dest)
1874 goto out_dput;
1875
1876 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
1877 if (err)
1878 goto out_dput;
1879
1880 /* check if subvolume may be deleted by a non-root user */
1881 err = btrfs_may_delete(dir, dentry, 1);
1882 if (err)
1883 goto out_dput;
1884 }
1885
1886 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1887 err = -EINVAL;
1888 goto out_dput;
1889 }
1890
1891 mutex_lock(&inode->i_mutex);
1892 err = d_invalidate(dentry);
1893 if (err)
1894 goto out_unlock;
1895
1896 down_write(&root->fs_info->subvol_sem);
1897
1898 err = may_destroy_subvol(dest);
1899 if (err)
1900 goto out_up_write;
1901
1902 trans = btrfs_start_transaction(root, 0);
1903 if (IS_ERR(trans)) {
1904 err = PTR_ERR(trans);
1905 goto out_up_write;
1906 }
1907 trans->block_rsv = &root->fs_info->global_block_rsv;
1908
1909 ret = btrfs_unlink_subvol(trans, root, dir,
1910 dest->root_key.objectid,
1911 dentry->d_name.name,
1912 dentry->d_name.len);
1913 BUG_ON(ret);
1914
1915 btrfs_record_root_in_trans(trans, dest);
1916
1917 memset(&dest->root_item.drop_progress, 0,
1918 sizeof(dest->root_item.drop_progress));
1919 dest->root_item.drop_level = 0;
1920 btrfs_set_root_refs(&dest->root_item, 0);
1921
1922 if (!xchg(&dest->orphan_item_inserted, 1)) {
1923 ret = btrfs_insert_orphan_item(trans,
1924 root->fs_info->tree_root,
1925 dest->root_key.objectid);
1926 BUG_ON(ret);
1927 }
1928
1929 ret = btrfs_end_transaction(trans, root);
1930 BUG_ON(ret);
1931 inode->i_flags |= S_DEAD;
1932out_up_write:
1933 up_write(&root->fs_info->subvol_sem);
1934out_unlock:
1935 mutex_unlock(&inode->i_mutex);
1936 if (!err) {
1937 shrink_dcache_sb(root->fs_info->sb);
1938 btrfs_invalidate_inodes(dest);
1939 d_delete(dentry);
1940 }
1941out_dput:
1942 dput(dentry);
1943out_unlock_dir:
1944 mutex_unlock(&dir->i_mutex);
1945 mnt_drop_write(file->f_path.mnt);
1946out:
1947 kfree(vol_args);
1948 return err;
1949}
1950
1951static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
1952{
1953 struct inode *inode = fdentry(file)->d_inode;
1954 struct btrfs_root *root = BTRFS_I(inode)->root;
1955 struct btrfs_ioctl_defrag_range_args *range;
1956 int ret;
1957
1958 if (btrfs_root_readonly(root))
1959 return -EROFS;
1960
1961 ret = mnt_want_write(file->f_path.mnt);
1962 if (ret)
1963 return ret;
1964
1965 switch (inode->i_mode & S_IFMT) {
1966 case S_IFDIR:
1967 if (!capable(CAP_SYS_ADMIN)) {
1968 ret = -EPERM;
1969 goto out;
1970 }
1971 ret = btrfs_defrag_root(root, 0);
1972 if (ret)
1973 goto out;
1974 ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
1975 break;
1976 case S_IFREG:
1977 if (!(file->f_mode & FMODE_WRITE)) {
1978 ret = -EINVAL;
1979 goto out;
1980 }
1981
1982 range = kzalloc(sizeof(*range), GFP_KERNEL);
1983 if (!range) {
1984 ret = -ENOMEM;
1985 goto out;
1986 }
1987
1988 if (argp) {
1989 if (copy_from_user(range, argp,
1990 sizeof(*range))) {
1991 ret = -EFAULT;
1992 kfree(range);
1993 goto out;
1994 }
1995 /* compression requires us to start the IO */
1996 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1997 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
1998 range->extent_thresh = (u32)-1;
1999 }
2000 } else {
2001 /* the rest are all set to zero by kzalloc */
2002 range->len = (u64)-1;
2003 }
2004 ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
2005 range, 0, 0);
2006 if (ret > 0)
2007 ret = 0;
2008 kfree(range);
2009 break;
2010 default:
2011 ret = -EINVAL;
2012 }
2013out:
2014 mnt_drop_write(file->f_path.mnt);
2015 return ret;
2016}
2017
2018static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2019{
2020 struct btrfs_ioctl_vol_args *vol_args;
2021 int ret;
2022
2023 if (!capable(CAP_SYS_ADMIN))
2024 return -EPERM;
2025
2026 vol_args = memdup_user(arg, sizeof(*vol_args));
2027 if (IS_ERR(vol_args))
2028 return PTR_ERR(vol_args);
2029
2030 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2031 ret = btrfs_init_new_device(root, vol_args->name);
2032
2033 kfree(vol_args);
2034 return ret;
2035}
2036
2037static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
2038{
2039 struct btrfs_ioctl_vol_args *vol_args;
2040 int ret;
2041
2042 if (!capable(CAP_SYS_ADMIN))
2043 return -EPERM;
2044
2045 if (root->fs_info->sb->s_flags & MS_RDONLY)
2046 return -EROFS;
2047
2048 vol_args = memdup_user(arg, sizeof(*vol_args));
2049 if (IS_ERR(vol_args))
2050 return PTR_ERR(vol_args);
2051
2052 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2053 ret = btrfs_rm_device(root, vol_args->name);
2054
2055 kfree(vol_args);
2056 return ret;
2057}
2058
2059static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2060{
2061 struct btrfs_ioctl_fs_info_args *fi_args;
2062 struct btrfs_device *device;
2063 struct btrfs_device *next;
2064 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2065 int ret = 0;
2066
2067 if (!capable(CAP_SYS_ADMIN))
2068 return -EPERM;
2069
2070 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2071 if (!fi_args)
2072 return -ENOMEM;
2073
2074 fi_args->num_devices = fs_devices->num_devices;
2075 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2076
2077 mutex_lock(&fs_devices->device_list_mutex);
2078 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2079 if (device->devid > fi_args->max_id)
2080 fi_args->max_id = device->devid;
2081 }
2082 mutex_unlock(&fs_devices->device_list_mutex);
2083
2084 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2085 ret = -EFAULT;
2086
2087 kfree(fi_args);
2088 return ret;
2089}
2090
2091static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2092{
2093 struct btrfs_ioctl_dev_info_args *di_args;
2094 struct btrfs_device *dev;
2095 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2096 int ret = 0;
2097 char *s_uuid = NULL;
2098 char empty_uuid[BTRFS_UUID_SIZE] = {0};
2099
2100 if (!capable(CAP_SYS_ADMIN))
2101 return -EPERM;
2102
2103 di_args = memdup_user(arg, sizeof(*di_args));
2104 if (IS_ERR(di_args))
2105 return PTR_ERR(di_args);
2106
2107 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2108 s_uuid = di_args->uuid;
2109
2110 mutex_lock(&fs_devices->device_list_mutex);
2111 dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL);
2112 mutex_unlock(&fs_devices->device_list_mutex);
2113
2114 if (!dev) {
2115 ret = -ENODEV;
2116 goto out;
2117 }
2118
2119 di_args->devid = dev->devid;
2120 di_args->bytes_used = dev->bytes_used;
2121 di_args->total_bytes = dev->total_bytes;
2122 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2123 strncpy(di_args->path, dev->name, sizeof(di_args->path));
2124
2125out:
2126 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2127 ret = -EFAULT;
2128
2129 kfree(di_args);
2130 return ret;
2131}
2132
2133static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2134 u64 off, u64 olen, u64 destoff)
2135{
2136 struct inode *inode = fdentry(file)->d_inode;
2137 struct btrfs_root *root = BTRFS_I(inode)->root;
2138 struct file *src_file;
2139 struct inode *src;
2140 struct btrfs_trans_handle *trans;
2141 struct btrfs_path *path;
2142 struct extent_buffer *leaf;
2143 char *buf;
2144 struct btrfs_key key;
2145 u32 nritems;
2146 int slot;
2147 int ret;
2148 u64 len = olen;
2149 u64 bs = root->fs_info->sb->s_blocksize;
2150 u64 hint_byte;
2151
2152 /*
2153 * TODO:
2154 * - split compressed inline extents. annoying: we need to
2155 * decompress into destination's address_space (the file offset
2156 * may change, so source mapping won't do), then recompress (or
2157 * otherwise reinsert) a subrange.
2158 * - allow ranges within the same file to be cloned (provided
2159 * they don't overlap)?
2160 */
2161
2162 /* the destination must be opened for writing */
2163 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2164 return -EINVAL;
2165
2166 if (btrfs_root_readonly(root))
2167 return -EROFS;
2168
2169 ret = mnt_want_write(file->f_path.mnt);
2170 if (ret)
2171 return ret;
2172
2173 src_file = fget(srcfd);
2174 if (!src_file) {
2175 ret = -EBADF;
2176 goto out_drop_write;
2177 }
2178
2179 src = src_file->f_dentry->d_inode;
2180
2181 ret = -EINVAL;
2182 if (src == inode)
2183 goto out_fput;
2184
2185 /* the src must be open for reading */
2186 if (!(src_file->f_mode & FMODE_READ))
2187 goto out_fput;
2188
2189 /* don't make the dst file partly checksummed */
2190 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2191 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2192 goto out_fput;
2193
2194 ret = -EISDIR;
2195 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2196 goto out_fput;
2197
2198 ret = -EXDEV;
2199 if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
2200 goto out_fput;
2201
2202 ret = -ENOMEM;
2203 buf = vmalloc(btrfs_level_size(root, 0));
2204 if (!buf)
2205 goto out_fput;
2206
2207 path = btrfs_alloc_path();
2208 if (!path) {
2209 vfree(buf);
2210 goto out_fput;
2211 }
2212 path->reada = 2;
2213
2214 if (inode < src) {
2215 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2216 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2217 } else {
2218 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2219 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2220 }
2221
2222 /* determine range to clone */
2223 ret = -EINVAL;
2224 if (off + len > src->i_size || off + len < off)
2225 goto out_unlock;
2226 if (len == 0)
2227 olen = len = src->i_size - off;
2228 /* if we extend to eof, continue to block boundary */
2229 if (off + len == src->i_size)
2230 len = ALIGN(src->i_size, bs) - off;
2231
2232 /* verify the end result is block aligned */
2233 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2234 !IS_ALIGNED(destoff, bs))
2235 goto out_unlock;
2236
2237 if (destoff > inode->i_size) {
2238 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2239 if (ret)
2240 goto out_unlock;
2241 }
2242
2243 /* truncate page cache pages from target inode range */
2244 truncate_inode_pages_range(&inode->i_data, destoff,
2245 PAGE_CACHE_ALIGN(destoff + len) - 1);
2246
2247 /* do any pending delalloc/csum calc on src, one way or
2248 another, and lock file content */
2249 while (1) {
2250 struct btrfs_ordered_extent *ordered;
2251 lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2252 ordered = btrfs_lookup_first_ordered_extent(src, off+len);
2253 if (!ordered &&
2254 !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len,
2255 EXTENT_DELALLOC, 0, NULL))
2256 break;
2257 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2258 if (ordered)
2259 btrfs_put_ordered_extent(ordered);
2260 btrfs_wait_ordered_range(src, off, len);
2261 }
2262
2263 /* clone data */
2264 key.objectid = btrfs_ino(src);
2265 key.type = BTRFS_EXTENT_DATA_KEY;
2266 key.offset = 0;
2267
2268 while (1) {
2269 /*
2270 * note the key will change type as we walk through the
2271 * tree.
2272 */
2273 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2274 if (ret < 0)
2275 goto out;
2276
2277 nritems = btrfs_header_nritems(path->nodes[0]);
2278 if (path->slots[0] >= nritems) {
2279 ret = btrfs_next_leaf(root, path);
2280 if (ret < 0)
2281 goto out;
2282 if (ret > 0)
2283 break;
2284 nritems = btrfs_header_nritems(path->nodes[0]);
2285 }
2286 leaf = path->nodes[0];
2287 slot = path->slots[0];
2288
2289 btrfs_item_key_to_cpu(leaf, &key, slot);
2290 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2291 key.objectid != btrfs_ino(src))
2292 break;
2293
2294 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2295 struct btrfs_file_extent_item *extent;
2296 int type;
2297 u32 size;
2298 struct btrfs_key new_key;
2299 u64 disko = 0, diskl = 0;
2300 u64 datao = 0, datal = 0;
2301 u8 comp;
2302 u64 endoff;
2303
2304 size = btrfs_item_size_nr(leaf, slot);
2305 read_extent_buffer(leaf, buf,
2306 btrfs_item_ptr_offset(leaf, slot),
2307 size);
2308
2309 extent = btrfs_item_ptr(leaf, slot,
2310 struct btrfs_file_extent_item);
2311 comp = btrfs_file_extent_compression(leaf, extent);
2312 type = btrfs_file_extent_type(leaf, extent);
2313 if (type == BTRFS_FILE_EXTENT_REG ||
2314 type == BTRFS_FILE_EXTENT_PREALLOC) {
2315 disko = btrfs_file_extent_disk_bytenr(leaf,
2316 extent);
2317 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2318 extent);
2319 datao = btrfs_file_extent_offset(leaf, extent);
2320 datal = btrfs_file_extent_num_bytes(leaf,
2321 extent);
2322 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2323 /* take upper bound, may be compressed */
2324 datal = btrfs_file_extent_ram_bytes(leaf,
2325 extent);
2326 }
2327 btrfs_release_path(path);
2328
2329 if (key.offset + datal <= off ||
2330 key.offset >= off+len)
2331 goto next;
2332
2333 memcpy(&new_key, &key, sizeof(new_key));
2334 new_key.objectid = btrfs_ino(inode);
2335 if (off <= key.offset)
2336 new_key.offset = key.offset + destoff - off;
2337 else
2338 new_key.offset = destoff;
2339
2340 /*
2341 * 1 - adjusting old extent (we may have to split it)
2342 * 1 - add new extent
2343 * 1 - inode update
2344 */
2345 trans = btrfs_start_transaction(root, 3);
2346 if (IS_ERR(trans)) {
2347 ret = PTR_ERR(trans);
2348 goto out;
2349 }
2350
2351 if (type == BTRFS_FILE_EXTENT_REG ||
2352 type == BTRFS_FILE_EXTENT_PREALLOC) {
2353 /*
2354 * a | --- range to clone ---| b
2355 * | ------------- extent ------------- |
2356 */
2357
2358 /* substract range b */
2359 if (key.offset + datal > off + len)
2360 datal = off + len - key.offset;
2361
2362 /* substract range a */
2363 if (off > key.offset) {
2364 datao += off - key.offset;
2365 datal -= off - key.offset;
2366 }
2367
2368 ret = btrfs_drop_extents(trans, inode,
2369 new_key.offset,
2370 new_key.offset + datal,
2371 &hint_byte, 1);
2372 BUG_ON(ret);
2373
2374 ret = btrfs_insert_empty_item(trans, root, path,
2375 &new_key, size);
2376 BUG_ON(ret);
2377
2378 leaf = path->nodes[0];
2379 slot = path->slots[0];
2380 write_extent_buffer(leaf, buf,
2381 btrfs_item_ptr_offset(leaf, slot),
2382 size);
2383
2384 extent = btrfs_item_ptr(leaf, slot,
2385 struct btrfs_file_extent_item);
2386
2387 /* disko == 0 means it's a hole */
2388 if (!disko)
2389 datao = 0;
2390
2391 btrfs_set_file_extent_offset(leaf, extent,
2392 datao);
2393 btrfs_set_file_extent_num_bytes(leaf, extent,
2394 datal);
2395 if (disko) {
2396 inode_add_bytes(inode, datal);
2397 ret = btrfs_inc_extent_ref(trans, root,
2398 disko, diskl, 0,
2399 root->root_key.objectid,
2400 btrfs_ino(inode),
2401 new_key.offset - datao);
2402 BUG_ON(ret);
2403 }
2404 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2405 u64 skip = 0;
2406 u64 trim = 0;
2407 if (off > key.offset) {
2408 skip = off - key.offset;
2409 new_key.offset += skip;
2410 }
2411
2412 if (key.offset + datal > off+len)
2413 trim = key.offset + datal - (off+len);
2414
2415 if (comp && (skip || trim)) {
2416 ret = -EINVAL;
2417 btrfs_end_transaction(trans, root);
2418 goto out;
2419 }
2420 size -= skip + trim;
2421 datal -= skip + trim;
2422
2423 ret = btrfs_drop_extents(trans, inode,
2424 new_key.offset,
2425 new_key.offset + datal,
2426 &hint_byte, 1);
2427 BUG_ON(ret);
2428
2429 ret = btrfs_insert_empty_item(trans, root, path,
2430 &new_key, size);
2431 BUG_ON(ret);
2432
2433 if (skip) {
2434 u32 start =
2435 btrfs_file_extent_calc_inline_size(0);
2436 memmove(buf+start, buf+start+skip,
2437 datal);
2438 }
2439
2440 leaf = path->nodes[0];
2441 slot = path->slots[0];
2442 write_extent_buffer(leaf, buf,
2443 btrfs_item_ptr_offset(leaf, slot),
2444 size);
2445 inode_add_bytes(inode, datal);
2446 }
2447
2448 btrfs_mark_buffer_dirty(leaf);
2449 btrfs_release_path(path);
2450
2451 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2452
2453 /*
2454 * we round up to the block size at eof when
2455 * determining which extents to clone above,
2456 * but shouldn't round up the file size
2457 */
2458 endoff = new_key.offset + datal;
2459 if (endoff > destoff+olen)
2460 endoff = destoff+olen;
2461 if (endoff > inode->i_size)
2462 btrfs_i_size_write(inode, endoff);
2463
2464 ret = btrfs_update_inode(trans, root, inode);
2465 BUG_ON(ret);
2466 btrfs_end_transaction(trans, root);
2467 }
2468next:
2469 btrfs_release_path(path);
2470 key.offset++;
2471 }
2472 ret = 0;
2473out:
2474 btrfs_release_path(path);
2475 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2476out_unlock:
2477 mutex_unlock(&src->i_mutex);
2478 mutex_unlock(&inode->i_mutex);
2479 vfree(buf);
2480 btrfs_free_path(path);
2481out_fput:
2482 fput(src_file);
2483out_drop_write:
2484 mnt_drop_write(file->f_path.mnt);
2485 return ret;
2486}
2487
2488static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2489{
2490 struct btrfs_ioctl_clone_range_args args;
2491
2492 if (copy_from_user(&args, argp, sizeof(args)))
2493 return -EFAULT;
2494 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2495 args.src_length, args.dest_offset);
2496}
2497
2498/*
2499 * there are many ways the trans_start and trans_end ioctls can lead
2500 * to deadlocks. They should only be used by applications that
2501 * basically own the machine, and have a very in depth understanding
2502 * of all the possible deadlocks and enospc problems.
2503 */
2504static long btrfs_ioctl_trans_start(struct file *file)
2505{
2506 struct inode *inode = fdentry(file)->d_inode;
2507 struct btrfs_root *root = BTRFS_I(inode)->root;
2508 struct btrfs_trans_handle *trans;
2509 int ret;
2510
2511 ret = -EPERM;
2512 if (!capable(CAP_SYS_ADMIN))
2513 goto out;
2514
2515 ret = -EINPROGRESS;
2516 if (file->private_data)
2517 goto out;
2518
2519 ret = -EROFS;
2520 if (btrfs_root_readonly(root))
2521 goto out;
2522
2523 ret = mnt_want_write(file->f_path.mnt);
2524 if (ret)
2525 goto out;
2526
2527 atomic_inc(&root->fs_info->open_ioctl_trans);
2528
2529 ret = -ENOMEM;
2530 trans = btrfs_start_ioctl_transaction(root);
2531 if (IS_ERR(trans))
2532 goto out_drop;
2533
2534 file->private_data = trans;
2535 return 0;
2536
2537out_drop:
2538 atomic_dec(&root->fs_info->open_ioctl_trans);
2539 mnt_drop_write(file->f_path.mnt);
2540out:
2541 return ret;
2542}
2543
2544static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2545{
2546 struct inode *inode = fdentry(file)->d_inode;
2547 struct btrfs_root *root = BTRFS_I(inode)->root;
2548 struct btrfs_root *new_root;
2549 struct btrfs_dir_item *di;
2550 struct btrfs_trans_handle *trans;
2551 struct btrfs_path *path;
2552 struct btrfs_key location;
2553 struct btrfs_disk_key disk_key;
2554 struct btrfs_super_block *disk_super;
2555 u64 features;
2556 u64 objectid = 0;
2557 u64 dir_id;
2558
2559 if (!capable(CAP_SYS_ADMIN))
2560 return -EPERM;
2561
2562 if (copy_from_user(&objectid, argp, sizeof(objectid)))
2563 return -EFAULT;
2564
2565 if (!objectid)
2566 objectid = root->root_key.objectid;
2567
2568 location.objectid = objectid;
2569 location.type = BTRFS_ROOT_ITEM_KEY;
2570 location.offset = (u64)-1;
2571
2572 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2573 if (IS_ERR(new_root))
2574 return PTR_ERR(new_root);
2575
2576 if (btrfs_root_refs(&new_root->root_item) == 0)
2577 return -ENOENT;
2578
2579 path = btrfs_alloc_path();
2580 if (!path)
2581 return -ENOMEM;
2582 path->leave_spinning = 1;
2583
2584 trans = btrfs_start_transaction(root, 1);
2585 if (IS_ERR(trans)) {
2586 btrfs_free_path(path);
2587 return PTR_ERR(trans);
2588 }
2589
2590 dir_id = btrfs_super_root_dir(&root->fs_info->super_copy);
2591 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2592 dir_id, "default", 7, 1);
2593 if (IS_ERR_OR_NULL(di)) {
2594 btrfs_free_path(path);
2595 btrfs_end_transaction(trans, root);
2596 printk(KERN_ERR "Umm, you don't have the default dir item, "
2597 "this isn't going to work\n");
2598 return -ENOENT;
2599 }
2600
2601 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2602 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2603 btrfs_mark_buffer_dirty(path->nodes[0]);
2604 btrfs_free_path(path);
2605
2606 disk_super = &root->fs_info->super_copy;
2607 features = btrfs_super_incompat_flags(disk_super);
2608 if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) {
2609 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL;
2610 btrfs_set_super_incompat_flags(disk_super, features);
2611 }
2612 btrfs_end_transaction(trans, root);
2613
2614 return 0;
2615}
2616
2617static void get_block_group_info(struct list_head *groups_list,
2618 struct btrfs_ioctl_space_info *space)
2619{
2620 struct btrfs_block_group_cache *block_group;
2621
2622 space->total_bytes = 0;
2623 space->used_bytes = 0;
2624 space->flags = 0;
2625 list_for_each_entry(block_group, groups_list, list) {
2626 space->flags = block_group->flags;
2627 space->total_bytes += block_group->key.offset;
2628 space->used_bytes +=
2629 btrfs_block_group_used(&block_group->item);
2630 }
2631}
2632
2633long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
2634{
2635 struct btrfs_ioctl_space_args space_args;
2636 struct btrfs_ioctl_space_info space;
2637 struct btrfs_ioctl_space_info *dest;
2638 struct btrfs_ioctl_space_info *dest_orig;
2639 struct btrfs_ioctl_space_info __user *user_dest;
2640 struct btrfs_space_info *info;
2641 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2642 BTRFS_BLOCK_GROUP_SYSTEM,
2643 BTRFS_BLOCK_GROUP_METADATA,
2644 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
2645 int num_types = 4;
2646 int alloc_size;
2647 int ret = 0;
2648 u64 slot_count = 0;
2649 int i, c;
2650
2651 if (copy_from_user(&space_args,
2652 (struct btrfs_ioctl_space_args __user *)arg,
2653 sizeof(space_args)))
2654 return -EFAULT;
2655
2656 for (i = 0; i < num_types; i++) {
2657 struct btrfs_space_info *tmp;
2658
2659 info = NULL;
2660 rcu_read_lock();
2661 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2662 list) {
2663 if (tmp->flags == types[i]) {
2664 info = tmp;
2665 break;
2666 }
2667 }
2668 rcu_read_unlock();
2669
2670 if (!info)
2671 continue;
2672
2673 down_read(&info->groups_sem);
2674 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2675 if (!list_empty(&info->block_groups[c]))
2676 slot_count++;
2677 }
2678 up_read(&info->groups_sem);
2679 }
2680
2681 /* space_slots == 0 means they are asking for a count */
2682 if (space_args.space_slots == 0) {
2683 space_args.total_spaces = slot_count;
2684 goto out;
2685 }
2686
2687 slot_count = min_t(u64, space_args.space_slots, slot_count);
2688
2689 alloc_size = sizeof(*dest) * slot_count;
2690
2691 /* we generally have at most 6 or so space infos, one for each raid
2692 * level. So, a whole page should be more than enough for everyone
2693 */
2694 if (alloc_size > PAGE_CACHE_SIZE)
2695 return -ENOMEM;
2696
2697 space_args.total_spaces = 0;
2698 dest = kmalloc(alloc_size, GFP_NOFS);
2699 if (!dest)
2700 return -ENOMEM;
2701 dest_orig = dest;
2702
2703 /* now we have a buffer to copy into */
2704 for (i = 0; i < num_types; i++) {
2705 struct btrfs_space_info *tmp;
2706
2707 if (!slot_count)
2708 break;
2709
2710 info = NULL;
2711 rcu_read_lock();
2712 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2713 list) {
2714 if (tmp->flags == types[i]) {
2715 info = tmp;
2716 break;
2717 }
2718 }
2719 rcu_read_unlock();
2720
2721 if (!info)
2722 continue;
2723 down_read(&info->groups_sem);
2724 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2725 if (!list_empty(&info->block_groups[c])) {
2726 get_block_group_info(&info->block_groups[c],
2727 &space);
2728 memcpy(dest, &space, sizeof(space));
2729 dest++;
2730 space_args.total_spaces++;
2731 slot_count--;
2732 }
2733 if (!slot_count)
2734 break;
2735 }
2736 up_read(&info->groups_sem);
2737 }
2738
2739 user_dest = (struct btrfs_ioctl_space_info *)
2740 (arg + sizeof(struct btrfs_ioctl_space_args));
2741
2742 if (copy_to_user(user_dest, dest_orig, alloc_size))
2743 ret = -EFAULT;
2744
2745 kfree(dest_orig);
2746out:
2747 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
2748 ret = -EFAULT;
2749
2750 return ret;
2751}
2752
2753/*
2754 * there are many ways the trans_start and trans_end ioctls can lead
2755 * to deadlocks. They should only be used by applications that
2756 * basically own the machine, and have a very in depth understanding
2757 * of all the possible deadlocks and enospc problems.
2758 */
2759long btrfs_ioctl_trans_end(struct file *file)
2760{
2761 struct inode *inode = fdentry(file)->d_inode;
2762 struct btrfs_root *root = BTRFS_I(inode)->root;
2763 struct btrfs_trans_handle *trans;
2764
2765 trans = file->private_data;
2766 if (!trans)
2767 return -EINVAL;
2768 file->private_data = NULL;
2769
2770 btrfs_end_transaction(trans, root);
2771
2772 atomic_dec(&root->fs_info->open_ioctl_trans);
2773
2774 mnt_drop_write(file->f_path.mnt);
2775 return 0;
2776}
2777
2778static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
2779{
2780 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2781 struct btrfs_trans_handle *trans;
2782 u64 transid;
2783 int ret;
2784
2785 trans = btrfs_start_transaction(root, 0);
2786 if (IS_ERR(trans))
2787 return PTR_ERR(trans);
2788 transid = trans->transid;
2789 ret = btrfs_commit_transaction_async(trans, root, 0);
2790 if (ret) {
2791 btrfs_end_transaction(trans, root);
2792 return ret;
2793 }
2794
2795 if (argp)
2796 if (copy_to_user(argp, &transid, sizeof(transid)))
2797 return -EFAULT;
2798 return 0;
2799}
2800
2801static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
2802{
2803 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2804 u64 transid;
2805
2806 if (argp) {
2807 if (copy_from_user(&transid, argp, sizeof(transid)))
2808 return -EFAULT;
2809 } else {
2810 transid = 0; /* current trans */
2811 }
2812 return btrfs_wait_for_commit(root, transid);
2813}
2814
2815static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg)
2816{
2817 int ret;
2818 struct btrfs_ioctl_scrub_args *sa;
2819
2820 if (!capable(CAP_SYS_ADMIN))
2821 return -EPERM;
2822
2823 sa = memdup_user(arg, sizeof(*sa));
2824 if (IS_ERR(sa))
2825 return PTR_ERR(sa);
2826
2827 ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end,
2828 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY);
2829
2830 if (copy_to_user(arg, sa, sizeof(*sa)))
2831 ret = -EFAULT;
2832
2833 kfree(sa);
2834 return ret;
2835}
2836
2837static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
2838{
2839 if (!capable(CAP_SYS_ADMIN))
2840 return -EPERM;
2841
2842 return btrfs_scrub_cancel(root);
2843}
2844
2845static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
2846 void __user *arg)
2847{
2848 struct btrfs_ioctl_scrub_args *sa;
2849 int ret;
2850
2851 if (!capable(CAP_SYS_ADMIN))
2852 return -EPERM;
2853
2854 sa = memdup_user(arg, sizeof(*sa));
2855 if (IS_ERR(sa))
2856 return PTR_ERR(sa);
2857
2858 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
2859
2860 if (copy_to_user(arg, sa, sizeof(*sa)))
2861 ret = -EFAULT;
2862
2863 kfree(sa);
2864 return ret;
2865}
2866
2867long btrfs_ioctl(struct file *file, unsigned int
2868 cmd, unsigned long arg)
2869{
2870 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2871 void __user *argp = (void __user *)arg;
2872
2873 switch (cmd) {
2874 case FS_IOC_GETFLAGS:
2875 return btrfs_ioctl_getflags(file, argp);
2876 case FS_IOC_SETFLAGS:
2877 return btrfs_ioctl_setflags(file, argp);
2878 case FS_IOC_GETVERSION:
2879 return btrfs_ioctl_getversion(file, argp);
2880 case FITRIM:
2881 return btrfs_ioctl_fitrim(file, argp);
2882 case BTRFS_IOC_SNAP_CREATE:
2883 return btrfs_ioctl_snap_create(file, argp, 0);
2884 case BTRFS_IOC_SNAP_CREATE_V2:
2885 return btrfs_ioctl_snap_create_v2(file, argp, 0);
2886 case BTRFS_IOC_SUBVOL_CREATE:
2887 return btrfs_ioctl_snap_create(file, argp, 1);
2888 case BTRFS_IOC_SNAP_DESTROY:
2889 return btrfs_ioctl_snap_destroy(file, argp);
2890 case BTRFS_IOC_SUBVOL_GETFLAGS:
2891 return btrfs_ioctl_subvol_getflags(file, argp);
2892 case BTRFS_IOC_SUBVOL_SETFLAGS:
2893 return btrfs_ioctl_subvol_setflags(file, argp);
2894 case BTRFS_IOC_DEFAULT_SUBVOL:
2895 return btrfs_ioctl_default_subvol(file, argp);
2896 case BTRFS_IOC_DEFRAG:
2897 return btrfs_ioctl_defrag(file, NULL);
2898 case BTRFS_IOC_DEFRAG_RANGE:
2899 return btrfs_ioctl_defrag(file, argp);
2900 case BTRFS_IOC_RESIZE:
2901 return btrfs_ioctl_resize(root, argp);
2902 case BTRFS_IOC_ADD_DEV:
2903 return btrfs_ioctl_add_dev(root, argp);
2904 case BTRFS_IOC_RM_DEV:
2905 return btrfs_ioctl_rm_dev(root, argp);
2906 case BTRFS_IOC_FS_INFO:
2907 return btrfs_ioctl_fs_info(root, argp);
2908 case BTRFS_IOC_DEV_INFO:
2909 return btrfs_ioctl_dev_info(root, argp);
2910 case BTRFS_IOC_BALANCE:
2911 return btrfs_balance(root->fs_info->dev_root);
2912 case BTRFS_IOC_CLONE:
2913 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
2914 case BTRFS_IOC_CLONE_RANGE:
2915 return btrfs_ioctl_clone_range(file, argp);
2916 case BTRFS_IOC_TRANS_START:
2917 return btrfs_ioctl_trans_start(file);
2918 case BTRFS_IOC_TRANS_END:
2919 return btrfs_ioctl_trans_end(file);
2920 case BTRFS_IOC_TREE_SEARCH:
2921 return btrfs_ioctl_tree_search(file, argp);
2922 case BTRFS_IOC_INO_LOOKUP:
2923 return btrfs_ioctl_ino_lookup(file, argp);
2924 case BTRFS_IOC_SPACE_INFO:
2925 return btrfs_ioctl_space_info(root, argp);
2926 case BTRFS_IOC_SYNC:
2927 btrfs_sync_fs(file->f_dentry->d_sb, 1);
2928 return 0;
2929 case BTRFS_IOC_START_SYNC:
2930 return btrfs_ioctl_start_sync(file, argp);
2931 case BTRFS_IOC_WAIT_SYNC:
2932 return btrfs_ioctl_wait_sync(file, argp);
2933 case BTRFS_IOC_SCRUB:
2934 return btrfs_ioctl_scrub(root, argp);
2935 case BTRFS_IOC_SCRUB_CANCEL:
2936 return btrfs_ioctl_scrub_cancel(root, argp);
2937 case BTRFS_IOC_SCRUB_PROGRESS:
2938 return btrfs_ioctl_scrub_progress(root, argp);
2939 }
2940
2941 return -ENOTTY;
2942}
1/*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19#include <linux/kernel.h>
20#include <linux/bio.h>
21#include <linux/buffer_head.h>
22#include <linux/file.h>
23#include <linux/fs.h>
24#include <linux/fsnotify.h>
25#include <linux/pagemap.h>
26#include <linux/highmem.h>
27#include <linux/time.h>
28#include <linux/init.h>
29#include <linux/string.h>
30#include <linux/backing-dev.h>
31#include <linux/mount.h>
32#include <linux/mpage.h>
33#include <linux/namei.h>
34#include <linux/swap.h>
35#include <linux/writeback.h>
36#include <linux/statfs.h>
37#include <linux/compat.h>
38#include <linux/bit_spinlock.h>
39#include <linux/security.h>
40#include <linux/xattr.h>
41#include <linux/vmalloc.h>
42#include <linux/slab.h>
43#include <linux/blkdev.h>
44#include <linux/uuid.h>
45#include <linux/btrfs.h>
46#include <linux/uaccess.h>
47#include "ctree.h"
48#include "disk-io.h"
49#include "transaction.h"
50#include "btrfs_inode.h"
51#include "print-tree.h"
52#include "volumes.h"
53#include "locking.h"
54#include "inode-map.h"
55#include "backref.h"
56#include "rcu-string.h"
57#include "send.h"
58#include "dev-replace.h"
59#include "props.h"
60#include "sysfs.h"
61
62#ifdef CONFIG_64BIT
63/* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
64 * structures are incorrect, as the timespec structure from userspace
65 * is 4 bytes too small. We define these alternatives here to teach
66 * the kernel about the 32-bit struct packing.
67 */
68struct btrfs_ioctl_timespec_32 {
69 __u64 sec;
70 __u32 nsec;
71} __attribute__ ((__packed__));
72
73struct btrfs_ioctl_received_subvol_args_32 {
74 char uuid[BTRFS_UUID_SIZE]; /* in */
75 __u64 stransid; /* in */
76 __u64 rtransid; /* out */
77 struct btrfs_ioctl_timespec_32 stime; /* in */
78 struct btrfs_ioctl_timespec_32 rtime; /* out */
79 __u64 flags; /* in */
80 __u64 reserved[16]; /* in */
81} __attribute__ ((__packed__));
82
83#define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
84 struct btrfs_ioctl_received_subvol_args_32)
85#endif
86
87
88static int btrfs_clone(struct inode *src, struct inode *inode,
89 u64 off, u64 olen, u64 olen_aligned, u64 destoff);
90
91/* Mask out flags that are inappropriate for the given type of inode. */
92static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
93{
94 if (S_ISDIR(mode))
95 return flags;
96 else if (S_ISREG(mode))
97 return flags & ~FS_DIRSYNC_FL;
98 else
99 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
100}
101
102/*
103 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
104 */
105static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
106{
107 unsigned int iflags = 0;
108
109 if (flags & BTRFS_INODE_SYNC)
110 iflags |= FS_SYNC_FL;
111 if (flags & BTRFS_INODE_IMMUTABLE)
112 iflags |= FS_IMMUTABLE_FL;
113 if (flags & BTRFS_INODE_APPEND)
114 iflags |= FS_APPEND_FL;
115 if (flags & BTRFS_INODE_NODUMP)
116 iflags |= FS_NODUMP_FL;
117 if (flags & BTRFS_INODE_NOATIME)
118 iflags |= FS_NOATIME_FL;
119 if (flags & BTRFS_INODE_DIRSYNC)
120 iflags |= FS_DIRSYNC_FL;
121 if (flags & BTRFS_INODE_NODATACOW)
122 iflags |= FS_NOCOW_FL;
123
124 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
125 iflags |= FS_COMPR_FL;
126 else if (flags & BTRFS_INODE_NOCOMPRESS)
127 iflags |= FS_NOCOMP_FL;
128
129 return iflags;
130}
131
132/*
133 * Update inode->i_flags based on the btrfs internal flags.
134 */
135void btrfs_update_iflags(struct inode *inode)
136{
137 struct btrfs_inode *ip = BTRFS_I(inode);
138
139 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
140
141 if (ip->flags & BTRFS_INODE_SYNC)
142 inode->i_flags |= S_SYNC;
143 if (ip->flags & BTRFS_INODE_IMMUTABLE)
144 inode->i_flags |= S_IMMUTABLE;
145 if (ip->flags & BTRFS_INODE_APPEND)
146 inode->i_flags |= S_APPEND;
147 if (ip->flags & BTRFS_INODE_NOATIME)
148 inode->i_flags |= S_NOATIME;
149 if (ip->flags & BTRFS_INODE_DIRSYNC)
150 inode->i_flags |= S_DIRSYNC;
151}
152
153/*
154 * Inherit flags from the parent inode.
155 *
156 * Currently only the compression flags and the cow flags are inherited.
157 */
158void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
159{
160 unsigned int flags;
161
162 if (!dir)
163 return;
164
165 flags = BTRFS_I(dir)->flags;
166
167 if (flags & BTRFS_INODE_NOCOMPRESS) {
168 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
169 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
170 } else if (flags & BTRFS_INODE_COMPRESS) {
171 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
172 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
173 }
174
175 if (flags & BTRFS_INODE_NODATACOW) {
176 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
177 if (S_ISREG(inode->i_mode))
178 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
179 }
180
181 btrfs_update_iflags(inode);
182}
183
184static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
185{
186 struct btrfs_inode *ip = BTRFS_I(file_inode(file));
187 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
188
189 if (copy_to_user(arg, &flags, sizeof(flags)))
190 return -EFAULT;
191 return 0;
192}
193
194static int check_flags(unsigned int flags)
195{
196 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
197 FS_NOATIME_FL | FS_NODUMP_FL | \
198 FS_SYNC_FL | FS_DIRSYNC_FL | \
199 FS_NOCOMP_FL | FS_COMPR_FL |
200 FS_NOCOW_FL))
201 return -EOPNOTSUPP;
202
203 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
204 return -EINVAL;
205
206 return 0;
207}
208
209static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
210{
211 struct inode *inode = file_inode(file);
212 struct btrfs_inode *ip = BTRFS_I(inode);
213 struct btrfs_root *root = ip->root;
214 struct btrfs_trans_handle *trans;
215 unsigned int flags, oldflags;
216 int ret;
217 u64 ip_oldflags;
218 unsigned int i_oldflags;
219 umode_t mode;
220
221 if (!inode_owner_or_capable(inode))
222 return -EPERM;
223
224 if (btrfs_root_readonly(root))
225 return -EROFS;
226
227 if (copy_from_user(&flags, arg, sizeof(flags)))
228 return -EFAULT;
229
230 ret = check_flags(flags);
231 if (ret)
232 return ret;
233
234 ret = mnt_want_write_file(file);
235 if (ret)
236 return ret;
237
238 mutex_lock(&inode->i_mutex);
239
240 ip_oldflags = ip->flags;
241 i_oldflags = inode->i_flags;
242 mode = inode->i_mode;
243
244 flags = btrfs_mask_flags(inode->i_mode, flags);
245 oldflags = btrfs_flags_to_ioctl(ip->flags);
246 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
247 if (!capable(CAP_LINUX_IMMUTABLE)) {
248 ret = -EPERM;
249 goto out_unlock;
250 }
251 }
252
253 if (flags & FS_SYNC_FL)
254 ip->flags |= BTRFS_INODE_SYNC;
255 else
256 ip->flags &= ~BTRFS_INODE_SYNC;
257 if (flags & FS_IMMUTABLE_FL)
258 ip->flags |= BTRFS_INODE_IMMUTABLE;
259 else
260 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
261 if (flags & FS_APPEND_FL)
262 ip->flags |= BTRFS_INODE_APPEND;
263 else
264 ip->flags &= ~BTRFS_INODE_APPEND;
265 if (flags & FS_NODUMP_FL)
266 ip->flags |= BTRFS_INODE_NODUMP;
267 else
268 ip->flags &= ~BTRFS_INODE_NODUMP;
269 if (flags & FS_NOATIME_FL)
270 ip->flags |= BTRFS_INODE_NOATIME;
271 else
272 ip->flags &= ~BTRFS_INODE_NOATIME;
273 if (flags & FS_DIRSYNC_FL)
274 ip->flags |= BTRFS_INODE_DIRSYNC;
275 else
276 ip->flags &= ~BTRFS_INODE_DIRSYNC;
277 if (flags & FS_NOCOW_FL) {
278 if (S_ISREG(mode)) {
279 /*
280 * It's safe to turn csums off here, no extents exist.
281 * Otherwise we want the flag to reflect the real COW
282 * status of the file and will not set it.
283 */
284 if (inode->i_size == 0)
285 ip->flags |= BTRFS_INODE_NODATACOW
286 | BTRFS_INODE_NODATASUM;
287 } else {
288 ip->flags |= BTRFS_INODE_NODATACOW;
289 }
290 } else {
291 /*
292 * Revert back under same assuptions as above
293 */
294 if (S_ISREG(mode)) {
295 if (inode->i_size == 0)
296 ip->flags &= ~(BTRFS_INODE_NODATACOW
297 | BTRFS_INODE_NODATASUM);
298 } else {
299 ip->flags &= ~BTRFS_INODE_NODATACOW;
300 }
301 }
302
303 /*
304 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
305 * flag may be changed automatically if compression code won't make
306 * things smaller.
307 */
308 if (flags & FS_NOCOMP_FL) {
309 ip->flags &= ~BTRFS_INODE_COMPRESS;
310 ip->flags |= BTRFS_INODE_NOCOMPRESS;
311
312 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
313 if (ret && ret != -ENODATA)
314 goto out_drop;
315 } else if (flags & FS_COMPR_FL) {
316 const char *comp;
317
318 ip->flags |= BTRFS_INODE_COMPRESS;
319 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
320
321 if (root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
322 comp = "lzo";
323 else
324 comp = "zlib";
325 ret = btrfs_set_prop(inode, "btrfs.compression",
326 comp, strlen(comp), 0);
327 if (ret)
328 goto out_drop;
329
330 } else {
331 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
332 }
333
334 trans = btrfs_start_transaction(root, 1);
335 if (IS_ERR(trans)) {
336 ret = PTR_ERR(trans);
337 goto out_drop;
338 }
339
340 btrfs_update_iflags(inode);
341 inode_inc_iversion(inode);
342 inode->i_ctime = CURRENT_TIME;
343 ret = btrfs_update_inode(trans, root, inode);
344
345 btrfs_end_transaction(trans, root);
346 out_drop:
347 if (ret) {
348 ip->flags = ip_oldflags;
349 inode->i_flags = i_oldflags;
350 }
351
352 out_unlock:
353 mutex_unlock(&inode->i_mutex);
354 mnt_drop_write_file(file);
355 return ret;
356}
357
358static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
359{
360 struct inode *inode = file_inode(file);
361
362 return put_user(inode->i_generation, arg);
363}
364
365static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
366{
367 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
368 struct btrfs_device *device;
369 struct request_queue *q;
370 struct fstrim_range range;
371 u64 minlen = ULLONG_MAX;
372 u64 num_devices = 0;
373 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
374 int ret;
375
376 if (!capable(CAP_SYS_ADMIN))
377 return -EPERM;
378
379 rcu_read_lock();
380 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
381 dev_list) {
382 if (!device->bdev)
383 continue;
384 q = bdev_get_queue(device->bdev);
385 if (blk_queue_discard(q)) {
386 num_devices++;
387 minlen = min((u64)q->limits.discard_granularity,
388 minlen);
389 }
390 }
391 rcu_read_unlock();
392
393 if (!num_devices)
394 return -EOPNOTSUPP;
395 if (copy_from_user(&range, arg, sizeof(range)))
396 return -EFAULT;
397 if (range.start > total_bytes ||
398 range.len < fs_info->sb->s_blocksize)
399 return -EINVAL;
400
401 range.len = min(range.len, total_bytes - range.start);
402 range.minlen = max(range.minlen, minlen);
403 ret = btrfs_trim_fs(fs_info->tree_root, &range);
404 if (ret < 0)
405 return ret;
406
407 if (copy_to_user(arg, &range, sizeof(range)))
408 return -EFAULT;
409
410 return 0;
411}
412
413int btrfs_is_empty_uuid(u8 *uuid)
414{
415 int i;
416
417 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
418 if (uuid[i])
419 return 0;
420 }
421 return 1;
422}
423
424static noinline int create_subvol(struct inode *dir,
425 struct dentry *dentry,
426 char *name, int namelen,
427 u64 *async_transid,
428 struct btrfs_qgroup_inherit *inherit)
429{
430 struct btrfs_trans_handle *trans;
431 struct btrfs_key key;
432 struct btrfs_root_item root_item;
433 struct btrfs_inode_item *inode_item;
434 struct extent_buffer *leaf;
435 struct btrfs_root *root = BTRFS_I(dir)->root;
436 struct btrfs_root *new_root;
437 struct btrfs_block_rsv block_rsv;
438 struct timespec cur_time = CURRENT_TIME;
439 struct inode *inode;
440 int ret;
441 int err;
442 u64 objectid;
443 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
444 u64 index = 0;
445 u64 qgroup_reserved;
446 uuid_le new_uuid;
447
448 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
449 if (ret)
450 return ret;
451
452 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
453 /*
454 * The same as the snapshot creation, please see the comment
455 * of create_snapshot().
456 */
457 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
458 8, &qgroup_reserved, false);
459 if (ret)
460 return ret;
461
462 trans = btrfs_start_transaction(root, 0);
463 if (IS_ERR(trans)) {
464 ret = PTR_ERR(trans);
465 btrfs_subvolume_release_metadata(root, &block_rsv,
466 qgroup_reserved);
467 return ret;
468 }
469 trans->block_rsv = &block_rsv;
470 trans->bytes_reserved = block_rsv.size;
471
472 ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
473 if (ret)
474 goto fail;
475
476 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
477 0, objectid, NULL, 0, 0, 0);
478 if (IS_ERR(leaf)) {
479 ret = PTR_ERR(leaf);
480 goto fail;
481 }
482
483 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
484 btrfs_set_header_bytenr(leaf, leaf->start);
485 btrfs_set_header_generation(leaf, trans->transid);
486 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
487 btrfs_set_header_owner(leaf, objectid);
488
489 write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(),
490 BTRFS_FSID_SIZE);
491 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
492 btrfs_header_chunk_tree_uuid(leaf),
493 BTRFS_UUID_SIZE);
494 btrfs_mark_buffer_dirty(leaf);
495
496 memset(&root_item, 0, sizeof(root_item));
497
498 inode_item = &root_item.inode;
499 btrfs_set_stack_inode_generation(inode_item, 1);
500 btrfs_set_stack_inode_size(inode_item, 3);
501 btrfs_set_stack_inode_nlink(inode_item, 1);
502 btrfs_set_stack_inode_nbytes(inode_item, root->leafsize);
503 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
504
505 btrfs_set_root_flags(&root_item, 0);
506 btrfs_set_root_limit(&root_item, 0);
507 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
508
509 btrfs_set_root_bytenr(&root_item, leaf->start);
510 btrfs_set_root_generation(&root_item, trans->transid);
511 btrfs_set_root_level(&root_item, 0);
512 btrfs_set_root_refs(&root_item, 1);
513 btrfs_set_root_used(&root_item, leaf->len);
514 btrfs_set_root_last_snapshot(&root_item, 0);
515
516 btrfs_set_root_generation_v2(&root_item,
517 btrfs_root_generation(&root_item));
518 uuid_le_gen(&new_uuid);
519 memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
520 btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
521 btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec);
522 root_item.ctime = root_item.otime;
523 btrfs_set_root_ctransid(&root_item, trans->transid);
524 btrfs_set_root_otransid(&root_item, trans->transid);
525
526 btrfs_tree_unlock(leaf);
527 free_extent_buffer(leaf);
528 leaf = NULL;
529
530 btrfs_set_root_dirid(&root_item, new_dirid);
531
532 key.objectid = objectid;
533 key.offset = 0;
534 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
535 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
536 &root_item);
537 if (ret)
538 goto fail;
539
540 key.offset = (u64)-1;
541 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
542 if (IS_ERR(new_root)) {
543 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
544 ret = PTR_ERR(new_root);
545 goto fail;
546 }
547
548 btrfs_record_root_in_trans(trans, new_root);
549
550 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
551 if (ret) {
552 /* We potentially lose an unused inode item here */
553 btrfs_abort_transaction(trans, root, ret);
554 goto fail;
555 }
556
557 /*
558 * insert the directory item
559 */
560 ret = btrfs_set_inode_index(dir, &index);
561 if (ret) {
562 btrfs_abort_transaction(trans, root, ret);
563 goto fail;
564 }
565
566 ret = btrfs_insert_dir_item(trans, root,
567 name, namelen, dir, &key,
568 BTRFS_FT_DIR, index);
569 if (ret) {
570 btrfs_abort_transaction(trans, root, ret);
571 goto fail;
572 }
573
574 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
575 ret = btrfs_update_inode(trans, root, dir);
576 BUG_ON(ret);
577
578 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
579 objectid, root->root_key.objectid,
580 btrfs_ino(dir), index, name, namelen);
581 BUG_ON(ret);
582
583 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
584 root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
585 objectid);
586 if (ret)
587 btrfs_abort_transaction(trans, root, ret);
588
589fail:
590 trans->block_rsv = NULL;
591 trans->bytes_reserved = 0;
592 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
593
594 if (async_transid) {
595 *async_transid = trans->transid;
596 err = btrfs_commit_transaction_async(trans, root, 1);
597 if (err)
598 err = btrfs_commit_transaction(trans, root);
599 } else {
600 err = btrfs_commit_transaction(trans, root);
601 }
602 if (err && !ret)
603 ret = err;
604
605 if (!ret) {
606 inode = btrfs_lookup_dentry(dir, dentry);
607 if (IS_ERR(inode))
608 return PTR_ERR(inode);
609 d_instantiate(dentry, inode);
610 }
611 return ret;
612}
613
614static void btrfs_wait_nocow_write(struct btrfs_root *root)
615{
616 s64 writers;
617 DEFINE_WAIT(wait);
618
619 do {
620 prepare_to_wait(&root->subv_writers->wait, &wait,
621 TASK_UNINTERRUPTIBLE);
622
623 writers = percpu_counter_sum(&root->subv_writers->counter);
624 if (writers)
625 schedule();
626
627 finish_wait(&root->subv_writers->wait, &wait);
628 } while (writers);
629}
630
631static int create_snapshot(struct btrfs_root *root, struct inode *dir,
632 struct dentry *dentry, char *name, int namelen,
633 u64 *async_transid, bool readonly,
634 struct btrfs_qgroup_inherit *inherit)
635{
636 struct inode *inode;
637 struct btrfs_pending_snapshot *pending_snapshot;
638 struct btrfs_trans_handle *trans;
639 int ret;
640
641 if (!root->ref_cows)
642 return -EINVAL;
643
644 atomic_inc(&root->will_be_snapshoted);
645 smp_mb__after_atomic_inc();
646 btrfs_wait_nocow_write(root);
647
648 ret = btrfs_start_delalloc_inodes(root, 0);
649 if (ret)
650 goto out;
651
652 btrfs_wait_ordered_extents(root, -1);
653
654 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
655 if (!pending_snapshot) {
656 ret = -ENOMEM;
657 goto out;
658 }
659
660 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
661 BTRFS_BLOCK_RSV_TEMP);
662 /*
663 * 1 - parent dir inode
664 * 2 - dir entries
665 * 1 - root item
666 * 2 - root ref/backref
667 * 1 - root of snapshot
668 * 1 - UUID item
669 */
670 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
671 &pending_snapshot->block_rsv, 8,
672 &pending_snapshot->qgroup_reserved,
673 false);
674 if (ret)
675 goto free;
676
677 pending_snapshot->dentry = dentry;
678 pending_snapshot->root = root;
679 pending_snapshot->readonly = readonly;
680 pending_snapshot->dir = dir;
681 pending_snapshot->inherit = inherit;
682
683 trans = btrfs_start_transaction(root, 0);
684 if (IS_ERR(trans)) {
685 ret = PTR_ERR(trans);
686 goto fail;
687 }
688
689 spin_lock(&root->fs_info->trans_lock);
690 list_add(&pending_snapshot->list,
691 &trans->transaction->pending_snapshots);
692 spin_unlock(&root->fs_info->trans_lock);
693 if (async_transid) {
694 *async_transid = trans->transid;
695 ret = btrfs_commit_transaction_async(trans,
696 root->fs_info->extent_root, 1);
697 if (ret)
698 ret = btrfs_commit_transaction(trans, root);
699 } else {
700 ret = btrfs_commit_transaction(trans,
701 root->fs_info->extent_root);
702 }
703 if (ret)
704 goto fail;
705
706 ret = pending_snapshot->error;
707 if (ret)
708 goto fail;
709
710 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
711 if (ret)
712 goto fail;
713
714 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
715 if (IS_ERR(inode)) {
716 ret = PTR_ERR(inode);
717 goto fail;
718 }
719
720 d_instantiate(dentry, inode);
721 ret = 0;
722fail:
723 btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
724 &pending_snapshot->block_rsv,
725 pending_snapshot->qgroup_reserved);
726free:
727 kfree(pending_snapshot);
728out:
729 atomic_dec(&root->will_be_snapshoted);
730 return ret;
731}
732
733/* copy of check_sticky in fs/namei.c()
734* It's inline, so penalty for filesystems that don't use sticky bit is
735* minimal.
736*/
737static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
738{
739 kuid_t fsuid = current_fsuid();
740
741 if (!(dir->i_mode & S_ISVTX))
742 return 0;
743 if (uid_eq(inode->i_uid, fsuid))
744 return 0;
745 if (uid_eq(dir->i_uid, fsuid))
746 return 0;
747 return !capable(CAP_FOWNER);
748}
749
750/* copy of may_delete in fs/namei.c()
751 * Check whether we can remove a link victim from directory dir, check
752 * whether the type of victim is right.
753 * 1. We can't do it if dir is read-only (done in permission())
754 * 2. We should have write and exec permissions on dir
755 * 3. We can't remove anything from append-only dir
756 * 4. We can't do anything with immutable dir (done in permission())
757 * 5. If the sticky bit on dir is set we should either
758 * a. be owner of dir, or
759 * b. be owner of victim, or
760 * c. have CAP_FOWNER capability
761 * 6. If the victim is append-only or immutable we can't do antyhing with
762 * links pointing to it.
763 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
764 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
765 * 9. We can't remove a root or mountpoint.
766 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
767 * nfs_async_unlink().
768 */
769
770static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
771{
772 int error;
773
774 if (!victim->d_inode)
775 return -ENOENT;
776
777 BUG_ON(victim->d_parent->d_inode != dir);
778 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
779
780 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
781 if (error)
782 return error;
783 if (IS_APPEND(dir))
784 return -EPERM;
785 if (btrfs_check_sticky(dir, victim->d_inode)||
786 IS_APPEND(victim->d_inode)||
787 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
788 return -EPERM;
789 if (isdir) {
790 if (!S_ISDIR(victim->d_inode->i_mode))
791 return -ENOTDIR;
792 if (IS_ROOT(victim))
793 return -EBUSY;
794 } else if (S_ISDIR(victim->d_inode->i_mode))
795 return -EISDIR;
796 if (IS_DEADDIR(dir))
797 return -ENOENT;
798 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
799 return -EBUSY;
800 return 0;
801}
802
803/* copy of may_create in fs/namei.c() */
804static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
805{
806 if (child->d_inode)
807 return -EEXIST;
808 if (IS_DEADDIR(dir))
809 return -ENOENT;
810 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
811}
812
813/*
814 * Create a new subvolume below @parent. This is largely modeled after
815 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
816 * inside this filesystem so it's quite a bit simpler.
817 */
818static noinline int btrfs_mksubvol(struct path *parent,
819 char *name, int namelen,
820 struct btrfs_root *snap_src,
821 u64 *async_transid, bool readonly,
822 struct btrfs_qgroup_inherit *inherit)
823{
824 struct inode *dir = parent->dentry->d_inode;
825 struct dentry *dentry;
826 int error;
827
828 error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
829 if (error == -EINTR)
830 return error;
831
832 dentry = lookup_one_len(name, parent->dentry, namelen);
833 error = PTR_ERR(dentry);
834 if (IS_ERR(dentry))
835 goto out_unlock;
836
837 error = -EEXIST;
838 if (dentry->d_inode)
839 goto out_dput;
840
841 error = btrfs_may_create(dir, dentry);
842 if (error)
843 goto out_dput;
844
845 /*
846 * even if this name doesn't exist, we may get hash collisions.
847 * check for them now when we can safely fail
848 */
849 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
850 dir->i_ino, name,
851 namelen);
852 if (error)
853 goto out_dput;
854
855 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
856
857 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
858 goto out_up_read;
859
860 if (snap_src) {
861 error = create_snapshot(snap_src, dir, dentry, name, namelen,
862 async_transid, readonly, inherit);
863 } else {
864 error = create_subvol(dir, dentry, name, namelen,
865 async_transid, inherit);
866 }
867 if (!error)
868 fsnotify_mkdir(dir, dentry);
869out_up_read:
870 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
871out_dput:
872 dput(dentry);
873out_unlock:
874 mutex_unlock(&dir->i_mutex);
875 return error;
876}
877
878/*
879 * When we're defragging a range, we don't want to kick it off again
880 * if it is really just waiting for delalloc to send it down.
881 * If we find a nice big extent or delalloc range for the bytes in the
882 * file you want to defrag, we return 0 to let you know to skip this
883 * part of the file
884 */
885static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
886{
887 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
888 struct extent_map *em = NULL;
889 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
890 u64 end;
891
892 read_lock(&em_tree->lock);
893 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
894 read_unlock(&em_tree->lock);
895
896 if (em) {
897 end = extent_map_end(em);
898 free_extent_map(em);
899 if (end - offset > thresh)
900 return 0;
901 }
902 /* if we already have a nice delalloc here, just stop */
903 thresh /= 2;
904 end = count_range_bits(io_tree, &offset, offset + thresh,
905 thresh, EXTENT_DELALLOC, 1);
906 if (end >= thresh)
907 return 0;
908 return 1;
909}
910
911/*
912 * helper function to walk through a file and find extents
913 * newer than a specific transid, and smaller than thresh.
914 *
915 * This is used by the defragging code to find new and small
916 * extents
917 */
918static int find_new_extents(struct btrfs_root *root,
919 struct inode *inode, u64 newer_than,
920 u64 *off, int thresh)
921{
922 struct btrfs_path *path;
923 struct btrfs_key min_key;
924 struct extent_buffer *leaf;
925 struct btrfs_file_extent_item *extent;
926 int type;
927 int ret;
928 u64 ino = btrfs_ino(inode);
929
930 path = btrfs_alloc_path();
931 if (!path)
932 return -ENOMEM;
933
934 min_key.objectid = ino;
935 min_key.type = BTRFS_EXTENT_DATA_KEY;
936 min_key.offset = *off;
937
938 while (1) {
939 path->keep_locks = 1;
940 ret = btrfs_search_forward(root, &min_key, path, newer_than);
941 if (ret != 0)
942 goto none;
943 path->keep_locks = 0;
944 btrfs_unlock_up_safe(path, 1);
945process_slot:
946 if (min_key.objectid != ino)
947 goto none;
948 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
949 goto none;
950
951 leaf = path->nodes[0];
952 extent = btrfs_item_ptr(leaf, path->slots[0],
953 struct btrfs_file_extent_item);
954
955 type = btrfs_file_extent_type(leaf, extent);
956 if (type == BTRFS_FILE_EXTENT_REG &&
957 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
958 check_defrag_in_cache(inode, min_key.offset, thresh)) {
959 *off = min_key.offset;
960 btrfs_free_path(path);
961 return 0;
962 }
963
964 path->slots[0]++;
965 if (path->slots[0] < btrfs_header_nritems(leaf)) {
966 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
967 goto process_slot;
968 }
969
970 if (min_key.offset == (u64)-1)
971 goto none;
972
973 min_key.offset++;
974 btrfs_release_path(path);
975 }
976none:
977 btrfs_free_path(path);
978 return -ENOENT;
979}
980
981static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
982{
983 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
984 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
985 struct extent_map *em;
986 u64 len = PAGE_CACHE_SIZE;
987
988 /*
989 * hopefully we have this extent in the tree already, try without
990 * the full extent lock
991 */
992 read_lock(&em_tree->lock);
993 em = lookup_extent_mapping(em_tree, start, len);
994 read_unlock(&em_tree->lock);
995
996 if (!em) {
997 struct extent_state *cached = NULL;
998 u64 end = start + len - 1;
999
1000 /* get the big lock and read metadata off disk */
1001 lock_extent_bits(io_tree, start, end, 0, &cached);
1002 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
1003 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
1004
1005 if (IS_ERR(em))
1006 return NULL;
1007 }
1008
1009 return em;
1010}
1011
1012static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1013{
1014 struct extent_map *next;
1015 bool ret = true;
1016
1017 /* this is the last extent */
1018 if (em->start + em->len >= i_size_read(inode))
1019 return false;
1020
1021 next = defrag_lookup_extent(inode, em->start + em->len);
1022 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE ||
1023 (em->block_start + em->block_len == next->block_start))
1024 ret = false;
1025
1026 free_extent_map(next);
1027 return ret;
1028}
1029
1030static int should_defrag_range(struct inode *inode, u64 start, int thresh,
1031 u64 *last_len, u64 *skip, u64 *defrag_end,
1032 int compress)
1033{
1034 struct extent_map *em;
1035 int ret = 1;
1036 bool next_mergeable = true;
1037
1038 /*
1039 * make sure that once we start defragging an extent, we keep on
1040 * defragging it
1041 */
1042 if (start < *defrag_end)
1043 return 1;
1044
1045 *skip = 0;
1046
1047 em = defrag_lookup_extent(inode, start);
1048 if (!em)
1049 return 0;
1050
1051 /* this will cover holes, and inline extents */
1052 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1053 ret = 0;
1054 goto out;
1055 }
1056
1057 next_mergeable = defrag_check_next_extent(inode, em);
1058
1059 /*
1060 * we hit a real extent, if it is big or the next extent is not a
1061 * real extent, don't bother defragging it
1062 */
1063 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1064 (em->len >= thresh || !next_mergeable))
1065 ret = 0;
1066out:
1067 /*
1068 * last_len ends up being a counter of how many bytes we've defragged.
1069 * every time we choose not to defrag an extent, we reset *last_len
1070 * so that the next tiny extent will force a defrag.
1071 *
1072 * The end result of this is that tiny extents before a single big
1073 * extent will force at least part of that big extent to be defragged.
1074 */
1075 if (ret) {
1076 *defrag_end = extent_map_end(em);
1077 } else {
1078 *last_len = 0;
1079 *skip = extent_map_end(em);
1080 *defrag_end = 0;
1081 }
1082
1083 free_extent_map(em);
1084 return ret;
1085}
1086
1087/*
1088 * it doesn't do much good to defrag one or two pages
1089 * at a time. This pulls in a nice chunk of pages
1090 * to COW and defrag.
1091 *
1092 * It also makes sure the delalloc code has enough
1093 * dirty data to avoid making new small extents as part
1094 * of the defrag
1095 *
1096 * It's a good idea to start RA on this range
1097 * before calling this.
1098 */
1099static int cluster_pages_for_defrag(struct inode *inode,
1100 struct page **pages,
1101 unsigned long start_index,
1102 unsigned long num_pages)
1103{
1104 unsigned long file_end;
1105 u64 isize = i_size_read(inode);
1106 u64 page_start;
1107 u64 page_end;
1108 u64 page_cnt;
1109 int ret;
1110 int i;
1111 int i_done;
1112 struct btrfs_ordered_extent *ordered;
1113 struct extent_state *cached_state = NULL;
1114 struct extent_io_tree *tree;
1115 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1116
1117 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1118 if (!isize || start_index > file_end)
1119 return 0;
1120
1121 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1122
1123 ret = btrfs_delalloc_reserve_space(inode,
1124 page_cnt << PAGE_CACHE_SHIFT);
1125 if (ret)
1126 return ret;
1127 i_done = 0;
1128 tree = &BTRFS_I(inode)->io_tree;
1129
1130 /* step one, lock all the pages */
1131 for (i = 0; i < page_cnt; i++) {
1132 struct page *page;
1133again:
1134 page = find_or_create_page(inode->i_mapping,
1135 start_index + i, mask);
1136 if (!page)
1137 break;
1138
1139 page_start = page_offset(page);
1140 page_end = page_start + PAGE_CACHE_SIZE - 1;
1141 while (1) {
1142 lock_extent_bits(tree, page_start, page_end,
1143 0, &cached_state);
1144 ordered = btrfs_lookup_ordered_extent(inode,
1145 page_start);
1146 unlock_extent_cached(tree, page_start, page_end,
1147 &cached_state, GFP_NOFS);
1148 if (!ordered)
1149 break;
1150
1151 unlock_page(page);
1152 btrfs_start_ordered_extent(inode, ordered, 1);
1153 btrfs_put_ordered_extent(ordered);
1154 lock_page(page);
1155 /*
1156 * we unlocked the page above, so we need check if
1157 * it was released or not.
1158 */
1159 if (page->mapping != inode->i_mapping) {
1160 unlock_page(page);
1161 page_cache_release(page);
1162 goto again;
1163 }
1164 }
1165
1166 if (!PageUptodate(page)) {
1167 btrfs_readpage(NULL, page);
1168 lock_page(page);
1169 if (!PageUptodate(page)) {
1170 unlock_page(page);
1171 page_cache_release(page);
1172 ret = -EIO;
1173 break;
1174 }
1175 }
1176
1177 if (page->mapping != inode->i_mapping) {
1178 unlock_page(page);
1179 page_cache_release(page);
1180 goto again;
1181 }
1182
1183 pages[i] = page;
1184 i_done++;
1185 }
1186 if (!i_done || ret)
1187 goto out;
1188
1189 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1190 goto out;
1191
1192 /*
1193 * so now we have a nice long stream of locked
1194 * and up to date pages, lets wait on them
1195 */
1196 for (i = 0; i < i_done; i++)
1197 wait_on_page_writeback(pages[i]);
1198
1199 page_start = page_offset(pages[0]);
1200 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1201
1202 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1203 page_start, page_end - 1, 0, &cached_state);
1204 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1205 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1206 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1207 &cached_state, GFP_NOFS);
1208
1209 if (i_done != page_cnt) {
1210 spin_lock(&BTRFS_I(inode)->lock);
1211 BTRFS_I(inode)->outstanding_extents++;
1212 spin_unlock(&BTRFS_I(inode)->lock);
1213 btrfs_delalloc_release_space(inode,
1214 (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1215 }
1216
1217
1218 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1219 &cached_state, GFP_NOFS);
1220
1221 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1222 page_start, page_end - 1, &cached_state,
1223 GFP_NOFS);
1224
1225 for (i = 0; i < i_done; i++) {
1226 clear_page_dirty_for_io(pages[i]);
1227 ClearPageChecked(pages[i]);
1228 set_page_extent_mapped(pages[i]);
1229 set_page_dirty(pages[i]);
1230 unlock_page(pages[i]);
1231 page_cache_release(pages[i]);
1232 }
1233 return i_done;
1234out:
1235 for (i = 0; i < i_done; i++) {
1236 unlock_page(pages[i]);
1237 page_cache_release(pages[i]);
1238 }
1239 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1240 return ret;
1241
1242}
1243
1244int btrfs_defrag_file(struct inode *inode, struct file *file,
1245 struct btrfs_ioctl_defrag_range_args *range,
1246 u64 newer_than, unsigned long max_to_defrag)
1247{
1248 struct btrfs_root *root = BTRFS_I(inode)->root;
1249 struct file_ra_state *ra = NULL;
1250 unsigned long last_index;
1251 u64 isize = i_size_read(inode);
1252 u64 last_len = 0;
1253 u64 skip = 0;
1254 u64 defrag_end = 0;
1255 u64 newer_off = range->start;
1256 unsigned long i;
1257 unsigned long ra_index = 0;
1258 int ret;
1259 int defrag_count = 0;
1260 int compress_type = BTRFS_COMPRESS_ZLIB;
1261 int extent_thresh = range->extent_thresh;
1262 unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1263 unsigned long cluster = max_cluster;
1264 u64 new_align = ~((u64)128 * 1024 - 1);
1265 struct page **pages = NULL;
1266
1267 if (isize == 0)
1268 return 0;
1269
1270 if (range->start >= isize)
1271 return -EINVAL;
1272
1273 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1274 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1275 return -EINVAL;
1276 if (range->compress_type)
1277 compress_type = range->compress_type;
1278 }
1279
1280 if (extent_thresh == 0)
1281 extent_thresh = 256 * 1024;
1282
1283 /*
1284 * if we were not given a file, allocate a readahead
1285 * context
1286 */
1287 if (!file) {
1288 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1289 if (!ra)
1290 return -ENOMEM;
1291 file_ra_state_init(ra, inode->i_mapping);
1292 } else {
1293 ra = &file->f_ra;
1294 }
1295
1296 pages = kmalloc_array(max_cluster, sizeof(struct page *),
1297 GFP_NOFS);
1298 if (!pages) {
1299 ret = -ENOMEM;
1300 goto out_ra;
1301 }
1302
1303 /* find the last page to defrag */
1304 if (range->start + range->len > range->start) {
1305 last_index = min_t(u64, isize - 1,
1306 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1307 } else {
1308 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1309 }
1310
1311 if (newer_than) {
1312 ret = find_new_extents(root, inode, newer_than,
1313 &newer_off, 64 * 1024);
1314 if (!ret) {
1315 range->start = newer_off;
1316 /*
1317 * we always align our defrag to help keep
1318 * the extents in the file evenly spaced
1319 */
1320 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1321 } else
1322 goto out_ra;
1323 } else {
1324 i = range->start >> PAGE_CACHE_SHIFT;
1325 }
1326 if (!max_to_defrag)
1327 max_to_defrag = last_index + 1;
1328
1329 /*
1330 * make writeback starts from i, so the defrag range can be
1331 * written sequentially.
1332 */
1333 if (i < inode->i_mapping->writeback_index)
1334 inode->i_mapping->writeback_index = i;
1335
1336 while (i <= last_index && defrag_count < max_to_defrag &&
1337 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1338 PAGE_CACHE_SHIFT)) {
1339 /*
1340 * make sure we stop running if someone unmounts
1341 * the FS
1342 */
1343 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1344 break;
1345
1346 if (btrfs_defrag_cancelled(root->fs_info)) {
1347 printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n");
1348 ret = -EAGAIN;
1349 break;
1350 }
1351
1352 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1353 extent_thresh, &last_len, &skip,
1354 &defrag_end, range->flags &
1355 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1356 unsigned long next;
1357 /*
1358 * the should_defrag function tells us how much to skip
1359 * bump our counter by the suggested amount
1360 */
1361 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1362 i = max(i + 1, next);
1363 continue;
1364 }
1365
1366 if (!newer_than) {
1367 cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1368 PAGE_CACHE_SHIFT) - i;
1369 cluster = min(cluster, max_cluster);
1370 } else {
1371 cluster = max_cluster;
1372 }
1373
1374 if (i + cluster > ra_index) {
1375 ra_index = max(i, ra_index);
1376 btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1377 cluster);
1378 ra_index += max_cluster;
1379 }
1380
1381 mutex_lock(&inode->i_mutex);
1382 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1383 BTRFS_I(inode)->force_compress = compress_type;
1384 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1385 if (ret < 0) {
1386 mutex_unlock(&inode->i_mutex);
1387 goto out_ra;
1388 }
1389
1390 defrag_count += ret;
1391 balance_dirty_pages_ratelimited(inode->i_mapping);
1392 mutex_unlock(&inode->i_mutex);
1393
1394 if (newer_than) {
1395 if (newer_off == (u64)-1)
1396 break;
1397
1398 if (ret > 0)
1399 i += ret;
1400
1401 newer_off = max(newer_off + 1,
1402 (u64)i << PAGE_CACHE_SHIFT);
1403
1404 ret = find_new_extents(root, inode,
1405 newer_than, &newer_off,
1406 64 * 1024);
1407 if (!ret) {
1408 range->start = newer_off;
1409 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1410 } else {
1411 break;
1412 }
1413 } else {
1414 if (ret > 0) {
1415 i += ret;
1416 last_len += ret << PAGE_CACHE_SHIFT;
1417 } else {
1418 i++;
1419 last_len = 0;
1420 }
1421 }
1422 }
1423
1424 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1425 filemap_flush(inode->i_mapping);
1426 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1427 &BTRFS_I(inode)->runtime_flags))
1428 filemap_flush(inode->i_mapping);
1429 }
1430
1431 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1432 /* the filemap_flush will queue IO into the worker threads, but
1433 * we have to make sure the IO is actually started and that
1434 * ordered extents get created before we return
1435 */
1436 atomic_inc(&root->fs_info->async_submit_draining);
1437 while (atomic_read(&root->fs_info->nr_async_submits) ||
1438 atomic_read(&root->fs_info->async_delalloc_pages)) {
1439 wait_event(root->fs_info->async_submit_wait,
1440 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1441 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1442 }
1443 atomic_dec(&root->fs_info->async_submit_draining);
1444 }
1445
1446 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1447 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1448 }
1449
1450 ret = defrag_count;
1451
1452out_ra:
1453 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1454 mutex_lock(&inode->i_mutex);
1455 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1456 mutex_unlock(&inode->i_mutex);
1457 }
1458 if (!file)
1459 kfree(ra);
1460 kfree(pages);
1461 return ret;
1462}
1463
1464static noinline int btrfs_ioctl_resize(struct file *file,
1465 void __user *arg)
1466{
1467 u64 new_size;
1468 u64 old_size;
1469 u64 devid = 1;
1470 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
1471 struct btrfs_ioctl_vol_args *vol_args;
1472 struct btrfs_trans_handle *trans;
1473 struct btrfs_device *device = NULL;
1474 char *sizestr;
1475 char *retptr;
1476 char *devstr = NULL;
1477 int ret = 0;
1478 int mod = 0;
1479
1480 if (!capable(CAP_SYS_ADMIN))
1481 return -EPERM;
1482
1483 ret = mnt_want_write_file(file);
1484 if (ret)
1485 return ret;
1486
1487 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1488 1)) {
1489 mnt_drop_write_file(file);
1490 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1491 }
1492
1493 mutex_lock(&root->fs_info->volume_mutex);
1494 vol_args = memdup_user(arg, sizeof(*vol_args));
1495 if (IS_ERR(vol_args)) {
1496 ret = PTR_ERR(vol_args);
1497 goto out;
1498 }
1499
1500 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1501
1502 sizestr = vol_args->name;
1503 devstr = strchr(sizestr, ':');
1504 if (devstr) {
1505 char *end;
1506 sizestr = devstr + 1;
1507 *devstr = '\0';
1508 devstr = vol_args->name;
1509 devid = simple_strtoull(devstr, &end, 10);
1510 if (!devid) {
1511 ret = -EINVAL;
1512 goto out_free;
1513 }
1514 btrfs_info(root->fs_info, "resizing devid %llu", devid);
1515 }
1516
1517 device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1518 if (!device) {
1519 btrfs_info(root->fs_info, "resizer unable to find device %llu",
1520 devid);
1521 ret = -ENODEV;
1522 goto out_free;
1523 }
1524
1525 if (!device->writeable) {
1526 btrfs_info(root->fs_info,
1527 "resizer unable to apply on readonly device %llu",
1528 devid);
1529 ret = -EPERM;
1530 goto out_free;
1531 }
1532
1533 if (!strcmp(sizestr, "max"))
1534 new_size = device->bdev->bd_inode->i_size;
1535 else {
1536 if (sizestr[0] == '-') {
1537 mod = -1;
1538 sizestr++;
1539 } else if (sizestr[0] == '+') {
1540 mod = 1;
1541 sizestr++;
1542 }
1543 new_size = memparse(sizestr, &retptr);
1544 if (*retptr != '\0' || new_size == 0) {
1545 ret = -EINVAL;
1546 goto out_free;
1547 }
1548 }
1549
1550 if (device->is_tgtdev_for_dev_replace) {
1551 ret = -EPERM;
1552 goto out_free;
1553 }
1554
1555 old_size = device->total_bytes;
1556
1557 if (mod < 0) {
1558 if (new_size > old_size) {
1559 ret = -EINVAL;
1560 goto out_free;
1561 }
1562 new_size = old_size - new_size;
1563 } else if (mod > 0) {
1564 if (new_size > ULLONG_MAX - old_size) {
1565 ret = -EINVAL;
1566 goto out_free;
1567 }
1568 new_size = old_size + new_size;
1569 }
1570
1571 if (new_size < 256 * 1024 * 1024) {
1572 ret = -EINVAL;
1573 goto out_free;
1574 }
1575 if (new_size > device->bdev->bd_inode->i_size) {
1576 ret = -EFBIG;
1577 goto out_free;
1578 }
1579
1580 do_div(new_size, root->sectorsize);
1581 new_size *= root->sectorsize;
1582
1583 printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n",
1584 rcu_str_deref(device->name), new_size);
1585
1586 if (new_size > old_size) {
1587 trans = btrfs_start_transaction(root, 0);
1588 if (IS_ERR(trans)) {
1589 ret = PTR_ERR(trans);
1590 goto out_free;
1591 }
1592 ret = btrfs_grow_device(trans, device, new_size);
1593 btrfs_commit_transaction(trans, root);
1594 } else if (new_size < old_size) {
1595 ret = btrfs_shrink_device(device, new_size);
1596 } /* equal, nothing need to do */
1597
1598out_free:
1599 kfree(vol_args);
1600out:
1601 mutex_unlock(&root->fs_info->volume_mutex);
1602 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1603 mnt_drop_write_file(file);
1604 return ret;
1605}
1606
1607static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1608 char *name, unsigned long fd, int subvol,
1609 u64 *transid, bool readonly,
1610 struct btrfs_qgroup_inherit *inherit)
1611{
1612 int namelen;
1613 int ret = 0;
1614
1615 ret = mnt_want_write_file(file);
1616 if (ret)
1617 goto out;
1618
1619 namelen = strlen(name);
1620 if (strchr(name, '/')) {
1621 ret = -EINVAL;
1622 goto out_drop_write;
1623 }
1624
1625 if (name[0] == '.' &&
1626 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1627 ret = -EEXIST;
1628 goto out_drop_write;
1629 }
1630
1631 if (subvol) {
1632 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1633 NULL, transid, readonly, inherit);
1634 } else {
1635 struct fd src = fdget(fd);
1636 struct inode *src_inode;
1637 if (!src.file) {
1638 ret = -EINVAL;
1639 goto out_drop_write;
1640 }
1641
1642 src_inode = file_inode(src.file);
1643 if (src_inode->i_sb != file_inode(file)->i_sb) {
1644 btrfs_info(BTRFS_I(src_inode)->root->fs_info,
1645 "Snapshot src from another FS");
1646 ret = -EXDEV;
1647 } else if (!inode_owner_or_capable(src_inode)) {
1648 /*
1649 * Subvolume creation is not restricted, but snapshots
1650 * are limited to own subvolumes only
1651 */
1652 ret = -EPERM;
1653 } else {
1654 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1655 BTRFS_I(src_inode)->root,
1656 transid, readonly, inherit);
1657 }
1658 fdput(src);
1659 }
1660out_drop_write:
1661 mnt_drop_write_file(file);
1662out:
1663 return ret;
1664}
1665
1666static noinline int btrfs_ioctl_snap_create(struct file *file,
1667 void __user *arg, int subvol)
1668{
1669 struct btrfs_ioctl_vol_args *vol_args;
1670 int ret;
1671
1672 vol_args = memdup_user(arg, sizeof(*vol_args));
1673 if (IS_ERR(vol_args))
1674 return PTR_ERR(vol_args);
1675 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1676
1677 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1678 vol_args->fd, subvol,
1679 NULL, false, NULL);
1680
1681 kfree(vol_args);
1682 return ret;
1683}
1684
1685static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1686 void __user *arg, int subvol)
1687{
1688 struct btrfs_ioctl_vol_args_v2 *vol_args;
1689 int ret;
1690 u64 transid = 0;
1691 u64 *ptr = NULL;
1692 bool readonly = false;
1693 struct btrfs_qgroup_inherit *inherit = NULL;
1694
1695 vol_args = memdup_user(arg, sizeof(*vol_args));
1696 if (IS_ERR(vol_args))
1697 return PTR_ERR(vol_args);
1698 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1699
1700 if (vol_args->flags &
1701 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1702 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1703 ret = -EOPNOTSUPP;
1704 goto out;
1705 }
1706
1707 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1708 ptr = &transid;
1709 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1710 readonly = true;
1711 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1712 if (vol_args->size > PAGE_CACHE_SIZE) {
1713 ret = -EINVAL;
1714 goto out;
1715 }
1716 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1717 if (IS_ERR(inherit)) {
1718 ret = PTR_ERR(inherit);
1719 goto out;
1720 }
1721 }
1722
1723 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1724 vol_args->fd, subvol, ptr,
1725 readonly, inherit);
1726
1727 if (ret == 0 && ptr &&
1728 copy_to_user(arg +
1729 offsetof(struct btrfs_ioctl_vol_args_v2,
1730 transid), ptr, sizeof(*ptr)))
1731 ret = -EFAULT;
1732out:
1733 kfree(vol_args);
1734 kfree(inherit);
1735 return ret;
1736}
1737
1738static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1739 void __user *arg)
1740{
1741 struct inode *inode = file_inode(file);
1742 struct btrfs_root *root = BTRFS_I(inode)->root;
1743 int ret = 0;
1744 u64 flags = 0;
1745
1746 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1747 return -EINVAL;
1748
1749 down_read(&root->fs_info->subvol_sem);
1750 if (btrfs_root_readonly(root))
1751 flags |= BTRFS_SUBVOL_RDONLY;
1752 up_read(&root->fs_info->subvol_sem);
1753
1754 if (copy_to_user(arg, &flags, sizeof(flags)))
1755 ret = -EFAULT;
1756
1757 return ret;
1758}
1759
1760static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1761 void __user *arg)
1762{
1763 struct inode *inode = file_inode(file);
1764 struct btrfs_root *root = BTRFS_I(inode)->root;
1765 struct btrfs_trans_handle *trans;
1766 u64 root_flags;
1767 u64 flags;
1768 int ret = 0;
1769
1770 if (!inode_owner_or_capable(inode))
1771 return -EPERM;
1772
1773 ret = mnt_want_write_file(file);
1774 if (ret)
1775 goto out;
1776
1777 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1778 ret = -EINVAL;
1779 goto out_drop_write;
1780 }
1781
1782 if (copy_from_user(&flags, arg, sizeof(flags))) {
1783 ret = -EFAULT;
1784 goto out_drop_write;
1785 }
1786
1787 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1788 ret = -EINVAL;
1789 goto out_drop_write;
1790 }
1791
1792 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1793 ret = -EOPNOTSUPP;
1794 goto out_drop_write;
1795 }
1796
1797 down_write(&root->fs_info->subvol_sem);
1798
1799 /* nothing to do */
1800 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1801 goto out_drop_sem;
1802
1803 root_flags = btrfs_root_flags(&root->root_item);
1804 if (flags & BTRFS_SUBVOL_RDONLY) {
1805 btrfs_set_root_flags(&root->root_item,
1806 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1807 } else {
1808 /*
1809 * Block RO -> RW transition if this subvolume is involved in
1810 * send
1811 */
1812 spin_lock(&root->root_item_lock);
1813 if (root->send_in_progress == 0) {
1814 btrfs_set_root_flags(&root->root_item,
1815 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1816 spin_unlock(&root->root_item_lock);
1817 } else {
1818 spin_unlock(&root->root_item_lock);
1819 btrfs_warn(root->fs_info,
1820 "Attempt to set subvolume %llu read-write during send",
1821 root->root_key.objectid);
1822 ret = -EPERM;
1823 goto out_drop_sem;
1824 }
1825 }
1826
1827 trans = btrfs_start_transaction(root, 1);
1828 if (IS_ERR(trans)) {
1829 ret = PTR_ERR(trans);
1830 goto out_reset;
1831 }
1832
1833 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1834 &root->root_key, &root->root_item);
1835
1836 btrfs_commit_transaction(trans, root);
1837out_reset:
1838 if (ret)
1839 btrfs_set_root_flags(&root->root_item, root_flags);
1840out_drop_sem:
1841 up_write(&root->fs_info->subvol_sem);
1842out_drop_write:
1843 mnt_drop_write_file(file);
1844out:
1845 return ret;
1846}
1847
1848/*
1849 * helper to check if the subvolume references other subvolumes
1850 */
1851static noinline int may_destroy_subvol(struct btrfs_root *root)
1852{
1853 struct btrfs_path *path;
1854 struct btrfs_dir_item *di;
1855 struct btrfs_key key;
1856 u64 dir_id;
1857 int ret;
1858
1859 path = btrfs_alloc_path();
1860 if (!path)
1861 return -ENOMEM;
1862
1863 /* Make sure this root isn't set as the default subvol */
1864 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
1865 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
1866 dir_id, "default", 7, 0);
1867 if (di && !IS_ERR(di)) {
1868 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1869 if (key.objectid == root->root_key.objectid) {
1870 ret = -EPERM;
1871 btrfs_err(root->fs_info, "deleting default subvolume "
1872 "%llu is not allowed", key.objectid);
1873 goto out;
1874 }
1875 btrfs_release_path(path);
1876 }
1877
1878 key.objectid = root->root_key.objectid;
1879 key.type = BTRFS_ROOT_REF_KEY;
1880 key.offset = (u64)-1;
1881
1882 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1883 &key, path, 0, 0);
1884 if (ret < 0)
1885 goto out;
1886 BUG_ON(ret == 0);
1887
1888 ret = 0;
1889 if (path->slots[0] > 0) {
1890 path->slots[0]--;
1891 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1892 if (key.objectid == root->root_key.objectid &&
1893 key.type == BTRFS_ROOT_REF_KEY)
1894 ret = -ENOTEMPTY;
1895 }
1896out:
1897 btrfs_free_path(path);
1898 return ret;
1899}
1900
1901static noinline int key_in_sk(struct btrfs_key *key,
1902 struct btrfs_ioctl_search_key *sk)
1903{
1904 struct btrfs_key test;
1905 int ret;
1906
1907 test.objectid = sk->min_objectid;
1908 test.type = sk->min_type;
1909 test.offset = sk->min_offset;
1910
1911 ret = btrfs_comp_cpu_keys(key, &test);
1912 if (ret < 0)
1913 return 0;
1914
1915 test.objectid = sk->max_objectid;
1916 test.type = sk->max_type;
1917 test.offset = sk->max_offset;
1918
1919 ret = btrfs_comp_cpu_keys(key, &test);
1920 if (ret > 0)
1921 return 0;
1922 return 1;
1923}
1924
1925static noinline int copy_to_sk(struct btrfs_root *root,
1926 struct btrfs_path *path,
1927 struct btrfs_key *key,
1928 struct btrfs_ioctl_search_key *sk,
1929 char *buf,
1930 unsigned long *sk_offset,
1931 int *num_found)
1932{
1933 u64 found_transid;
1934 struct extent_buffer *leaf;
1935 struct btrfs_ioctl_search_header sh;
1936 unsigned long item_off;
1937 unsigned long item_len;
1938 int nritems;
1939 int i;
1940 int slot;
1941 int ret = 0;
1942
1943 leaf = path->nodes[0];
1944 slot = path->slots[0];
1945 nritems = btrfs_header_nritems(leaf);
1946
1947 if (btrfs_header_generation(leaf) > sk->max_transid) {
1948 i = nritems;
1949 goto advance_key;
1950 }
1951 found_transid = btrfs_header_generation(leaf);
1952
1953 for (i = slot; i < nritems; i++) {
1954 item_off = btrfs_item_ptr_offset(leaf, i);
1955 item_len = btrfs_item_size_nr(leaf, i);
1956
1957 btrfs_item_key_to_cpu(leaf, key, i);
1958 if (!key_in_sk(key, sk))
1959 continue;
1960
1961 if (sizeof(sh) + item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1962 item_len = 0;
1963
1964 if (sizeof(sh) + item_len + *sk_offset >
1965 BTRFS_SEARCH_ARGS_BUFSIZE) {
1966 ret = 1;
1967 goto overflow;
1968 }
1969
1970 sh.objectid = key->objectid;
1971 sh.offset = key->offset;
1972 sh.type = key->type;
1973 sh.len = item_len;
1974 sh.transid = found_transid;
1975
1976 /* copy search result header */
1977 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1978 *sk_offset += sizeof(sh);
1979
1980 if (item_len) {
1981 char *p = buf + *sk_offset;
1982 /* copy the item */
1983 read_extent_buffer(leaf, p,
1984 item_off, item_len);
1985 *sk_offset += item_len;
1986 }
1987 (*num_found)++;
1988
1989 if (*num_found >= sk->nr_items)
1990 break;
1991 }
1992advance_key:
1993 ret = 0;
1994 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1995 key->offset++;
1996 else if (key->type < (u8)-1 && key->type < sk->max_type) {
1997 key->offset = 0;
1998 key->type++;
1999 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
2000 key->offset = 0;
2001 key->type = 0;
2002 key->objectid++;
2003 } else
2004 ret = 1;
2005overflow:
2006 return ret;
2007}
2008
2009static noinline int search_ioctl(struct inode *inode,
2010 struct btrfs_ioctl_search_args *args)
2011{
2012 struct btrfs_root *root;
2013 struct btrfs_key key;
2014 struct btrfs_path *path;
2015 struct btrfs_ioctl_search_key *sk = &args->key;
2016 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
2017 int ret;
2018 int num_found = 0;
2019 unsigned long sk_offset = 0;
2020
2021 path = btrfs_alloc_path();
2022 if (!path)
2023 return -ENOMEM;
2024
2025 if (sk->tree_id == 0) {
2026 /* search the root of the inode that was passed */
2027 root = BTRFS_I(inode)->root;
2028 } else {
2029 key.objectid = sk->tree_id;
2030 key.type = BTRFS_ROOT_ITEM_KEY;
2031 key.offset = (u64)-1;
2032 root = btrfs_read_fs_root_no_name(info, &key);
2033 if (IS_ERR(root)) {
2034 printk(KERN_ERR "BTRFS: could not find root %llu\n",
2035 sk->tree_id);
2036 btrfs_free_path(path);
2037 return -ENOENT;
2038 }
2039 }
2040
2041 key.objectid = sk->min_objectid;
2042 key.type = sk->min_type;
2043 key.offset = sk->min_offset;
2044
2045 path->keep_locks = 1;
2046
2047 while (1) {
2048 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2049 if (ret != 0) {
2050 if (ret > 0)
2051 ret = 0;
2052 goto err;
2053 }
2054 ret = copy_to_sk(root, path, &key, sk, args->buf,
2055 &sk_offset, &num_found);
2056 btrfs_release_path(path);
2057 if (ret || num_found >= sk->nr_items)
2058 break;
2059
2060 }
2061 ret = 0;
2062err:
2063 sk->nr_items = num_found;
2064 btrfs_free_path(path);
2065 return ret;
2066}
2067
2068static noinline int btrfs_ioctl_tree_search(struct file *file,
2069 void __user *argp)
2070{
2071 struct btrfs_ioctl_search_args *args;
2072 struct inode *inode;
2073 int ret;
2074
2075 if (!capable(CAP_SYS_ADMIN))
2076 return -EPERM;
2077
2078 args = memdup_user(argp, sizeof(*args));
2079 if (IS_ERR(args))
2080 return PTR_ERR(args);
2081
2082 inode = file_inode(file);
2083 ret = search_ioctl(inode, args);
2084 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2085 ret = -EFAULT;
2086 kfree(args);
2087 return ret;
2088}
2089
2090/*
2091 * Search INODE_REFs to identify path name of 'dirid' directory
2092 * in a 'tree_id' tree. and sets path name to 'name'.
2093 */
2094static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2095 u64 tree_id, u64 dirid, char *name)
2096{
2097 struct btrfs_root *root;
2098 struct btrfs_key key;
2099 char *ptr;
2100 int ret = -1;
2101 int slot;
2102 int len;
2103 int total_len = 0;
2104 struct btrfs_inode_ref *iref;
2105 struct extent_buffer *l;
2106 struct btrfs_path *path;
2107
2108 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2109 name[0]='\0';
2110 return 0;
2111 }
2112
2113 path = btrfs_alloc_path();
2114 if (!path)
2115 return -ENOMEM;
2116
2117 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2118
2119 key.objectid = tree_id;
2120 key.type = BTRFS_ROOT_ITEM_KEY;
2121 key.offset = (u64)-1;
2122 root = btrfs_read_fs_root_no_name(info, &key);
2123 if (IS_ERR(root)) {
2124 printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id);
2125 ret = -ENOENT;
2126 goto out;
2127 }
2128
2129 key.objectid = dirid;
2130 key.type = BTRFS_INODE_REF_KEY;
2131 key.offset = (u64)-1;
2132
2133 while (1) {
2134 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2135 if (ret < 0)
2136 goto out;
2137 else if (ret > 0) {
2138 ret = btrfs_previous_item(root, path, dirid,
2139 BTRFS_INODE_REF_KEY);
2140 if (ret < 0)
2141 goto out;
2142 else if (ret > 0) {
2143 ret = -ENOENT;
2144 goto out;
2145 }
2146 }
2147
2148 l = path->nodes[0];
2149 slot = path->slots[0];
2150 btrfs_item_key_to_cpu(l, &key, slot);
2151
2152 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2153 len = btrfs_inode_ref_name_len(l, iref);
2154 ptr -= len + 1;
2155 total_len += len + 1;
2156 if (ptr < name) {
2157 ret = -ENAMETOOLONG;
2158 goto out;
2159 }
2160
2161 *(ptr + len) = '/';
2162 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2163
2164 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2165 break;
2166
2167 btrfs_release_path(path);
2168 key.objectid = key.offset;
2169 key.offset = (u64)-1;
2170 dirid = key.objectid;
2171 }
2172 memmove(name, ptr, total_len);
2173 name[total_len] = '\0';
2174 ret = 0;
2175out:
2176 btrfs_free_path(path);
2177 return ret;
2178}
2179
2180static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2181 void __user *argp)
2182{
2183 struct btrfs_ioctl_ino_lookup_args *args;
2184 struct inode *inode;
2185 int ret;
2186
2187 if (!capable(CAP_SYS_ADMIN))
2188 return -EPERM;
2189
2190 args = memdup_user(argp, sizeof(*args));
2191 if (IS_ERR(args))
2192 return PTR_ERR(args);
2193
2194 inode = file_inode(file);
2195
2196 if (args->treeid == 0)
2197 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2198
2199 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2200 args->treeid, args->objectid,
2201 args->name);
2202
2203 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2204 ret = -EFAULT;
2205
2206 kfree(args);
2207 return ret;
2208}
2209
2210static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2211 void __user *arg)
2212{
2213 struct dentry *parent = file->f_path.dentry;
2214 struct dentry *dentry;
2215 struct inode *dir = parent->d_inode;
2216 struct inode *inode;
2217 struct btrfs_root *root = BTRFS_I(dir)->root;
2218 struct btrfs_root *dest = NULL;
2219 struct btrfs_ioctl_vol_args *vol_args;
2220 struct btrfs_trans_handle *trans;
2221 struct btrfs_block_rsv block_rsv;
2222 u64 qgroup_reserved;
2223 int namelen;
2224 int ret;
2225 int err = 0;
2226
2227 vol_args = memdup_user(arg, sizeof(*vol_args));
2228 if (IS_ERR(vol_args))
2229 return PTR_ERR(vol_args);
2230
2231 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2232 namelen = strlen(vol_args->name);
2233 if (strchr(vol_args->name, '/') ||
2234 strncmp(vol_args->name, "..", namelen) == 0) {
2235 err = -EINVAL;
2236 goto out;
2237 }
2238
2239 err = mnt_want_write_file(file);
2240 if (err)
2241 goto out;
2242
2243 err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
2244 if (err == -EINTR)
2245 goto out_drop_write;
2246 dentry = lookup_one_len(vol_args->name, parent, namelen);
2247 if (IS_ERR(dentry)) {
2248 err = PTR_ERR(dentry);
2249 goto out_unlock_dir;
2250 }
2251
2252 if (!dentry->d_inode) {
2253 err = -ENOENT;
2254 goto out_dput;
2255 }
2256
2257 inode = dentry->d_inode;
2258 dest = BTRFS_I(inode)->root;
2259 if (!capable(CAP_SYS_ADMIN)) {
2260 /*
2261 * Regular user. Only allow this with a special mount
2262 * option, when the user has write+exec access to the
2263 * subvol root, and when rmdir(2) would have been
2264 * allowed.
2265 *
2266 * Note that this is _not_ check that the subvol is
2267 * empty or doesn't contain data that we wouldn't
2268 * otherwise be able to delete.
2269 *
2270 * Users who want to delete empty subvols should try
2271 * rmdir(2).
2272 */
2273 err = -EPERM;
2274 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2275 goto out_dput;
2276
2277 /*
2278 * Do not allow deletion if the parent dir is the same
2279 * as the dir to be deleted. That means the ioctl
2280 * must be called on the dentry referencing the root
2281 * of the subvol, not a random directory contained
2282 * within it.
2283 */
2284 err = -EINVAL;
2285 if (root == dest)
2286 goto out_dput;
2287
2288 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2289 if (err)
2290 goto out_dput;
2291 }
2292
2293 /* check if subvolume may be deleted by a user */
2294 err = btrfs_may_delete(dir, dentry, 1);
2295 if (err)
2296 goto out_dput;
2297
2298 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2299 err = -EINVAL;
2300 goto out_dput;
2301 }
2302
2303 mutex_lock(&inode->i_mutex);
2304 err = d_invalidate(dentry);
2305 if (err)
2306 goto out_unlock;
2307
2308 down_write(&root->fs_info->subvol_sem);
2309
2310 err = may_destroy_subvol(dest);
2311 if (err)
2312 goto out_up_write;
2313
2314 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2315 /*
2316 * One for dir inode, two for dir entries, two for root
2317 * ref/backref.
2318 */
2319 err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2320 5, &qgroup_reserved, true);
2321 if (err)
2322 goto out_up_write;
2323
2324 trans = btrfs_start_transaction(root, 0);
2325 if (IS_ERR(trans)) {
2326 err = PTR_ERR(trans);
2327 goto out_release;
2328 }
2329 trans->block_rsv = &block_rsv;
2330 trans->bytes_reserved = block_rsv.size;
2331
2332 ret = btrfs_unlink_subvol(trans, root, dir,
2333 dest->root_key.objectid,
2334 dentry->d_name.name,
2335 dentry->d_name.len);
2336 if (ret) {
2337 err = ret;
2338 btrfs_abort_transaction(trans, root, ret);
2339 goto out_end_trans;
2340 }
2341
2342 btrfs_record_root_in_trans(trans, dest);
2343
2344 memset(&dest->root_item.drop_progress, 0,
2345 sizeof(dest->root_item.drop_progress));
2346 dest->root_item.drop_level = 0;
2347 btrfs_set_root_refs(&dest->root_item, 0);
2348
2349 if (!xchg(&dest->orphan_item_inserted, 1)) {
2350 ret = btrfs_insert_orphan_item(trans,
2351 root->fs_info->tree_root,
2352 dest->root_key.objectid);
2353 if (ret) {
2354 btrfs_abort_transaction(trans, root, ret);
2355 err = ret;
2356 goto out_end_trans;
2357 }
2358 }
2359
2360 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2361 dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
2362 dest->root_key.objectid);
2363 if (ret && ret != -ENOENT) {
2364 btrfs_abort_transaction(trans, root, ret);
2365 err = ret;
2366 goto out_end_trans;
2367 }
2368 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
2369 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2370 dest->root_item.received_uuid,
2371 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
2372 dest->root_key.objectid);
2373 if (ret && ret != -ENOENT) {
2374 btrfs_abort_transaction(trans, root, ret);
2375 err = ret;
2376 goto out_end_trans;
2377 }
2378 }
2379
2380out_end_trans:
2381 trans->block_rsv = NULL;
2382 trans->bytes_reserved = 0;
2383 ret = btrfs_end_transaction(trans, root);
2384 if (ret && !err)
2385 err = ret;
2386 inode->i_flags |= S_DEAD;
2387out_release:
2388 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2389out_up_write:
2390 up_write(&root->fs_info->subvol_sem);
2391out_unlock:
2392 mutex_unlock(&inode->i_mutex);
2393 if (!err) {
2394 shrink_dcache_sb(root->fs_info->sb);
2395 btrfs_invalidate_inodes(dest);
2396 d_delete(dentry);
2397
2398 /* the last ref */
2399 if (dest->cache_inode) {
2400 iput(dest->cache_inode);
2401 dest->cache_inode = NULL;
2402 }
2403 }
2404out_dput:
2405 dput(dentry);
2406out_unlock_dir:
2407 mutex_unlock(&dir->i_mutex);
2408out_drop_write:
2409 mnt_drop_write_file(file);
2410out:
2411 kfree(vol_args);
2412 return err;
2413}
2414
2415static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2416{
2417 struct inode *inode = file_inode(file);
2418 struct btrfs_root *root = BTRFS_I(inode)->root;
2419 struct btrfs_ioctl_defrag_range_args *range;
2420 int ret;
2421
2422 ret = mnt_want_write_file(file);
2423 if (ret)
2424 return ret;
2425
2426 if (btrfs_root_readonly(root)) {
2427 ret = -EROFS;
2428 goto out;
2429 }
2430
2431 switch (inode->i_mode & S_IFMT) {
2432 case S_IFDIR:
2433 if (!capable(CAP_SYS_ADMIN)) {
2434 ret = -EPERM;
2435 goto out;
2436 }
2437 ret = btrfs_defrag_root(root);
2438 if (ret)
2439 goto out;
2440 ret = btrfs_defrag_root(root->fs_info->extent_root);
2441 break;
2442 case S_IFREG:
2443 if (!(file->f_mode & FMODE_WRITE)) {
2444 ret = -EINVAL;
2445 goto out;
2446 }
2447
2448 range = kzalloc(sizeof(*range), GFP_KERNEL);
2449 if (!range) {
2450 ret = -ENOMEM;
2451 goto out;
2452 }
2453
2454 if (argp) {
2455 if (copy_from_user(range, argp,
2456 sizeof(*range))) {
2457 ret = -EFAULT;
2458 kfree(range);
2459 goto out;
2460 }
2461 /* compression requires us to start the IO */
2462 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2463 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2464 range->extent_thresh = (u32)-1;
2465 }
2466 } else {
2467 /* the rest are all set to zero by kzalloc */
2468 range->len = (u64)-1;
2469 }
2470 ret = btrfs_defrag_file(file_inode(file), file,
2471 range, 0, 0);
2472 if (ret > 0)
2473 ret = 0;
2474 kfree(range);
2475 break;
2476 default:
2477 ret = -EINVAL;
2478 }
2479out:
2480 mnt_drop_write_file(file);
2481 return ret;
2482}
2483
2484static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2485{
2486 struct btrfs_ioctl_vol_args *vol_args;
2487 int ret;
2488
2489 if (!capable(CAP_SYS_ADMIN))
2490 return -EPERM;
2491
2492 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2493 1)) {
2494 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2495 }
2496
2497 mutex_lock(&root->fs_info->volume_mutex);
2498 vol_args = memdup_user(arg, sizeof(*vol_args));
2499 if (IS_ERR(vol_args)) {
2500 ret = PTR_ERR(vol_args);
2501 goto out;
2502 }
2503
2504 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2505 ret = btrfs_init_new_device(root, vol_args->name);
2506
2507 kfree(vol_args);
2508out:
2509 mutex_unlock(&root->fs_info->volume_mutex);
2510 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2511 return ret;
2512}
2513
2514static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2515{
2516 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
2517 struct btrfs_ioctl_vol_args *vol_args;
2518 int ret;
2519
2520 if (!capable(CAP_SYS_ADMIN))
2521 return -EPERM;
2522
2523 ret = mnt_want_write_file(file);
2524 if (ret)
2525 return ret;
2526
2527 vol_args = memdup_user(arg, sizeof(*vol_args));
2528 if (IS_ERR(vol_args)) {
2529 ret = PTR_ERR(vol_args);
2530 goto out;
2531 }
2532
2533 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2534
2535 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2536 1)) {
2537 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2538 goto out;
2539 }
2540
2541 mutex_lock(&root->fs_info->volume_mutex);
2542 ret = btrfs_rm_device(root, vol_args->name);
2543 mutex_unlock(&root->fs_info->volume_mutex);
2544 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2545
2546out:
2547 kfree(vol_args);
2548 mnt_drop_write_file(file);
2549 return ret;
2550}
2551
2552static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2553{
2554 struct btrfs_ioctl_fs_info_args *fi_args;
2555 struct btrfs_device *device;
2556 struct btrfs_device *next;
2557 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2558 int ret = 0;
2559
2560 if (!capable(CAP_SYS_ADMIN))
2561 return -EPERM;
2562
2563 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2564 if (!fi_args)
2565 return -ENOMEM;
2566
2567 mutex_lock(&fs_devices->device_list_mutex);
2568 fi_args->num_devices = fs_devices->num_devices;
2569 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2570
2571 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2572 if (device->devid > fi_args->max_id)
2573 fi_args->max_id = device->devid;
2574 }
2575 mutex_unlock(&fs_devices->device_list_mutex);
2576
2577 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2578 ret = -EFAULT;
2579
2580 kfree(fi_args);
2581 return ret;
2582}
2583
2584static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2585{
2586 struct btrfs_ioctl_dev_info_args *di_args;
2587 struct btrfs_device *dev;
2588 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2589 int ret = 0;
2590 char *s_uuid = NULL;
2591
2592 if (!capable(CAP_SYS_ADMIN))
2593 return -EPERM;
2594
2595 di_args = memdup_user(arg, sizeof(*di_args));
2596 if (IS_ERR(di_args))
2597 return PTR_ERR(di_args);
2598
2599 if (!btrfs_is_empty_uuid(di_args->uuid))
2600 s_uuid = di_args->uuid;
2601
2602 mutex_lock(&fs_devices->device_list_mutex);
2603 dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2604
2605 if (!dev) {
2606 ret = -ENODEV;
2607 goto out;
2608 }
2609
2610 di_args->devid = dev->devid;
2611 di_args->bytes_used = dev->bytes_used;
2612 di_args->total_bytes = dev->total_bytes;
2613 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2614 if (dev->name) {
2615 struct rcu_string *name;
2616
2617 rcu_read_lock();
2618 name = rcu_dereference(dev->name);
2619 strncpy(di_args->path, name->str, sizeof(di_args->path));
2620 rcu_read_unlock();
2621 di_args->path[sizeof(di_args->path) - 1] = 0;
2622 } else {
2623 di_args->path[0] = '\0';
2624 }
2625
2626out:
2627 mutex_unlock(&fs_devices->device_list_mutex);
2628 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2629 ret = -EFAULT;
2630
2631 kfree(di_args);
2632 return ret;
2633}
2634
2635static struct page *extent_same_get_page(struct inode *inode, u64 off)
2636{
2637 struct page *page;
2638 pgoff_t index;
2639 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
2640
2641 index = off >> PAGE_CACHE_SHIFT;
2642
2643 page = grab_cache_page(inode->i_mapping, index);
2644 if (!page)
2645 return NULL;
2646
2647 if (!PageUptodate(page)) {
2648 if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
2649 0))
2650 return NULL;
2651 lock_page(page);
2652 if (!PageUptodate(page)) {
2653 unlock_page(page);
2654 page_cache_release(page);
2655 return NULL;
2656 }
2657 }
2658 unlock_page(page);
2659
2660 return page;
2661}
2662
2663static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
2664{
2665 /* do any pending delalloc/csum calc on src, one way or
2666 another, and lock file content */
2667 while (1) {
2668 struct btrfs_ordered_extent *ordered;
2669 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2670 ordered = btrfs_lookup_first_ordered_extent(inode,
2671 off + len - 1);
2672 if (!ordered &&
2673 !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2674 off + len - 1, EXTENT_DELALLOC, 0, NULL))
2675 break;
2676 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2677 if (ordered)
2678 btrfs_put_ordered_extent(ordered);
2679 btrfs_wait_ordered_range(inode, off, len);
2680 }
2681}
2682
2683static void btrfs_double_unlock(struct inode *inode1, u64 loff1,
2684 struct inode *inode2, u64 loff2, u64 len)
2685{
2686 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
2687 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
2688
2689 mutex_unlock(&inode1->i_mutex);
2690 mutex_unlock(&inode2->i_mutex);
2691}
2692
2693static void btrfs_double_lock(struct inode *inode1, u64 loff1,
2694 struct inode *inode2, u64 loff2, u64 len)
2695{
2696 if (inode1 < inode2) {
2697 swap(inode1, inode2);
2698 swap(loff1, loff2);
2699 }
2700
2701 mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
2702 lock_extent_range(inode1, loff1, len);
2703 if (inode1 != inode2) {
2704 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
2705 lock_extent_range(inode2, loff2, len);
2706 }
2707}
2708
2709static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
2710 u64 dst_loff, u64 len)
2711{
2712 int ret = 0;
2713 struct page *src_page, *dst_page;
2714 unsigned int cmp_len = PAGE_CACHE_SIZE;
2715 void *addr, *dst_addr;
2716
2717 while (len) {
2718 if (len < PAGE_CACHE_SIZE)
2719 cmp_len = len;
2720
2721 src_page = extent_same_get_page(src, loff);
2722 if (!src_page)
2723 return -EINVAL;
2724 dst_page = extent_same_get_page(dst, dst_loff);
2725 if (!dst_page) {
2726 page_cache_release(src_page);
2727 return -EINVAL;
2728 }
2729 addr = kmap_atomic(src_page);
2730 dst_addr = kmap_atomic(dst_page);
2731
2732 flush_dcache_page(src_page);
2733 flush_dcache_page(dst_page);
2734
2735 if (memcmp(addr, dst_addr, cmp_len))
2736 ret = BTRFS_SAME_DATA_DIFFERS;
2737
2738 kunmap_atomic(addr);
2739 kunmap_atomic(dst_addr);
2740 page_cache_release(src_page);
2741 page_cache_release(dst_page);
2742
2743 if (ret)
2744 break;
2745
2746 loff += cmp_len;
2747 dst_loff += cmp_len;
2748 len -= cmp_len;
2749 }
2750
2751 return ret;
2752}
2753
2754static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len)
2755{
2756 u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
2757
2758 if (off + len > inode->i_size || off + len < off)
2759 return -EINVAL;
2760 /* Check that we are block aligned - btrfs_clone() requires this */
2761 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
2762 return -EINVAL;
2763
2764 return 0;
2765}
2766
2767static int btrfs_extent_same(struct inode *src, u64 loff, u64 len,
2768 struct inode *dst, u64 dst_loff)
2769{
2770 int ret;
2771
2772 /*
2773 * btrfs_clone() can't handle extents in the same file
2774 * yet. Once that works, we can drop this check and replace it
2775 * with a check for the same inode, but overlapping extents.
2776 */
2777 if (src == dst)
2778 return -EINVAL;
2779
2780 btrfs_double_lock(src, loff, dst, dst_loff, len);
2781
2782 ret = extent_same_check_offsets(src, loff, len);
2783 if (ret)
2784 goto out_unlock;
2785
2786 ret = extent_same_check_offsets(dst, dst_loff, len);
2787 if (ret)
2788 goto out_unlock;
2789
2790 /* don't make the dst file partly checksummed */
2791 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2792 (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
2793 ret = -EINVAL;
2794 goto out_unlock;
2795 }
2796
2797 ret = btrfs_cmp_data(src, loff, dst, dst_loff, len);
2798 if (ret == 0)
2799 ret = btrfs_clone(src, dst, loff, len, len, dst_loff);
2800
2801out_unlock:
2802 btrfs_double_unlock(src, loff, dst, dst_loff, len);
2803
2804 return ret;
2805}
2806
2807#define BTRFS_MAX_DEDUPE_LEN (16 * 1024 * 1024)
2808
2809static long btrfs_ioctl_file_extent_same(struct file *file,
2810 struct btrfs_ioctl_same_args __user *argp)
2811{
2812 struct btrfs_ioctl_same_args *same;
2813 struct btrfs_ioctl_same_extent_info *info;
2814 struct inode *src = file_inode(file);
2815 u64 off;
2816 u64 len;
2817 int i;
2818 int ret;
2819 unsigned long size;
2820 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
2821 bool is_admin = capable(CAP_SYS_ADMIN);
2822 u16 count;
2823
2824 if (!(file->f_mode & FMODE_READ))
2825 return -EINVAL;
2826
2827 ret = mnt_want_write_file(file);
2828 if (ret)
2829 return ret;
2830
2831 if (get_user(count, &argp->dest_count)) {
2832 ret = -EFAULT;
2833 goto out;
2834 }
2835
2836 size = offsetof(struct btrfs_ioctl_same_args __user, info[count]);
2837
2838 same = memdup_user(argp, size);
2839
2840 if (IS_ERR(same)) {
2841 ret = PTR_ERR(same);
2842 goto out;
2843 }
2844
2845 off = same->logical_offset;
2846 len = same->length;
2847
2848 /*
2849 * Limit the total length we will dedupe for each operation.
2850 * This is intended to bound the total time spent in this
2851 * ioctl to something sane.
2852 */
2853 if (len > BTRFS_MAX_DEDUPE_LEN)
2854 len = BTRFS_MAX_DEDUPE_LEN;
2855
2856 if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
2857 /*
2858 * Btrfs does not support blocksize < page_size. As a
2859 * result, btrfs_cmp_data() won't correctly handle
2860 * this situation without an update.
2861 */
2862 ret = -EINVAL;
2863 goto out;
2864 }
2865
2866 ret = -EISDIR;
2867 if (S_ISDIR(src->i_mode))
2868 goto out;
2869
2870 ret = -EACCES;
2871 if (!S_ISREG(src->i_mode))
2872 goto out;
2873
2874 /* pre-format output fields to sane values */
2875 for (i = 0; i < count; i++) {
2876 same->info[i].bytes_deduped = 0ULL;
2877 same->info[i].status = 0;
2878 }
2879
2880 for (i = 0, info = same->info; i < count; i++, info++) {
2881 struct inode *dst;
2882 struct fd dst_file = fdget(info->fd);
2883 if (!dst_file.file) {
2884 info->status = -EBADF;
2885 continue;
2886 }
2887 dst = file_inode(dst_file.file);
2888
2889 if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) {
2890 info->status = -EINVAL;
2891 } else if (file->f_path.mnt != dst_file.file->f_path.mnt) {
2892 info->status = -EXDEV;
2893 } else if (S_ISDIR(dst->i_mode)) {
2894 info->status = -EISDIR;
2895 } else if (!S_ISREG(dst->i_mode)) {
2896 info->status = -EACCES;
2897 } else {
2898 info->status = btrfs_extent_same(src, off, len, dst,
2899 info->logical_offset);
2900 if (info->status == 0)
2901 info->bytes_deduped += len;
2902 }
2903 fdput(dst_file);
2904 }
2905
2906 ret = copy_to_user(argp, same, size);
2907 if (ret)
2908 ret = -EFAULT;
2909
2910out:
2911 mnt_drop_write_file(file);
2912 return ret;
2913}
2914
2915/**
2916 * btrfs_clone() - clone a range from inode file to another
2917 *
2918 * @src: Inode to clone from
2919 * @inode: Inode to clone to
2920 * @off: Offset within source to start clone from
2921 * @olen: Original length, passed by user, of range to clone
2922 * @olen_aligned: Block-aligned value of olen, extent_same uses
2923 * identical values here
2924 * @destoff: Offset within @inode to start clone
2925 */
2926static int btrfs_clone(struct inode *src, struct inode *inode,
2927 u64 off, u64 olen, u64 olen_aligned, u64 destoff)
2928{
2929 struct btrfs_root *root = BTRFS_I(inode)->root;
2930 struct btrfs_path *path = NULL;
2931 struct extent_buffer *leaf;
2932 struct btrfs_trans_handle *trans;
2933 char *buf = NULL;
2934 struct btrfs_key key;
2935 u32 nritems;
2936 int slot;
2937 int ret;
2938 u64 len = olen_aligned;
2939
2940 ret = -ENOMEM;
2941 buf = vmalloc(btrfs_level_size(root, 0));
2942 if (!buf)
2943 return ret;
2944
2945 path = btrfs_alloc_path();
2946 if (!path) {
2947 vfree(buf);
2948 return ret;
2949 }
2950
2951 path->reada = 2;
2952 /* clone data */
2953 key.objectid = btrfs_ino(src);
2954 key.type = BTRFS_EXTENT_DATA_KEY;
2955 key.offset = 0;
2956
2957 while (1) {
2958 /*
2959 * note the key will change type as we walk through the
2960 * tree.
2961 */
2962 path->leave_spinning = 1;
2963 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
2964 0, 0);
2965 if (ret < 0)
2966 goto out;
2967
2968 nritems = btrfs_header_nritems(path->nodes[0]);
2969process_slot:
2970 if (path->slots[0] >= nritems) {
2971 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
2972 if (ret < 0)
2973 goto out;
2974 if (ret > 0)
2975 break;
2976 nritems = btrfs_header_nritems(path->nodes[0]);
2977 }
2978 leaf = path->nodes[0];
2979 slot = path->slots[0];
2980
2981 btrfs_item_key_to_cpu(leaf, &key, slot);
2982 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2983 key.objectid != btrfs_ino(src))
2984 break;
2985
2986 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2987 struct btrfs_file_extent_item *extent;
2988 int type;
2989 u32 size;
2990 struct btrfs_key new_key;
2991 u64 disko = 0, diskl = 0;
2992 u64 datao = 0, datal = 0;
2993 u8 comp;
2994 u64 endoff;
2995
2996 extent = btrfs_item_ptr(leaf, slot,
2997 struct btrfs_file_extent_item);
2998 comp = btrfs_file_extent_compression(leaf, extent);
2999 type = btrfs_file_extent_type(leaf, extent);
3000 if (type == BTRFS_FILE_EXTENT_REG ||
3001 type == BTRFS_FILE_EXTENT_PREALLOC) {
3002 disko = btrfs_file_extent_disk_bytenr(leaf,
3003 extent);
3004 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3005 extent);
3006 datao = btrfs_file_extent_offset(leaf, extent);
3007 datal = btrfs_file_extent_num_bytes(leaf,
3008 extent);
3009 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3010 /* take upper bound, may be compressed */
3011 datal = btrfs_file_extent_ram_bytes(leaf,
3012 extent);
3013 }
3014
3015 if (key.offset + datal <= off ||
3016 key.offset >= off + len - 1) {
3017 path->slots[0]++;
3018 goto process_slot;
3019 }
3020
3021 size = btrfs_item_size_nr(leaf, slot);
3022 read_extent_buffer(leaf, buf,
3023 btrfs_item_ptr_offset(leaf, slot),
3024 size);
3025
3026 btrfs_release_path(path);
3027 path->leave_spinning = 0;
3028
3029 memcpy(&new_key, &key, sizeof(new_key));
3030 new_key.objectid = btrfs_ino(inode);
3031 if (off <= key.offset)
3032 new_key.offset = key.offset + destoff - off;
3033 else
3034 new_key.offset = destoff;
3035
3036 /*
3037 * 1 - adjusting old extent (we may have to split it)
3038 * 1 - add new extent
3039 * 1 - inode update
3040 */
3041 trans = btrfs_start_transaction(root, 3);
3042 if (IS_ERR(trans)) {
3043 ret = PTR_ERR(trans);
3044 goto out;
3045 }
3046
3047 if (type == BTRFS_FILE_EXTENT_REG ||
3048 type == BTRFS_FILE_EXTENT_PREALLOC) {
3049 /*
3050 * a | --- range to clone ---| b
3051 * | ------------- extent ------------- |
3052 */
3053
3054 /* substract range b */
3055 if (key.offset + datal > off + len)
3056 datal = off + len - key.offset;
3057
3058 /* substract range a */
3059 if (off > key.offset) {
3060 datao += off - key.offset;
3061 datal -= off - key.offset;
3062 }
3063
3064 ret = btrfs_drop_extents(trans, root, inode,
3065 new_key.offset,
3066 new_key.offset + datal,
3067 1);
3068 if (ret) {
3069 if (ret != -EOPNOTSUPP)
3070 btrfs_abort_transaction(trans,
3071 root, ret);
3072 btrfs_end_transaction(trans, root);
3073 goto out;
3074 }
3075
3076 ret = btrfs_insert_empty_item(trans, root, path,
3077 &new_key, size);
3078 if (ret) {
3079 btrfs_abort_transaction(trans, root,
3080 ret);
3081 btrfs_end_transaction(trans, root);
3082 goto out;
3083 }
3084
3085 leaf = path->nodes[0];
3086 slot = path->slots[0];
3087 write_extent_buffer(leaf, buf,
3088 btrfs_item_ptr_offset(leaf, slot),
3089 size);
3090
3091 extent = btrfs_item_ptr(leaf, slot,
3092 struct btrfs_file_extent_item);
3093
3094 /* disko == 0 means it's a hole */
3095 if (!disko)
3096 datao = 0;
3097
3098 btrfs_set_file_extent_offset(leaf, extent,
3099 datao);
3100 btrfs_set_file_extent_num_bytes(leaf, extent,
3101 datal);
3102 if (disko) {
3103 inode_add_bytes(inode, datal);
3104 ret = btrfs_inc_extent_ref(trans, root,
3105 disko, diskl, 0,
3106 root->root_key.objectid,
3107 btrfs_ino(inode),
3108 new_key.offset - datao,
3109 0);
3110 if (ret) {
3111 btrfs_abort_transaction(trans,
3112 root,
3113 ret);
3114 btrfs_end_transaction(trans,
3115 root);
3116 goto out;
3117
3118 }
3119 }
3120 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3121 u64 skip = 0;
3122 u64 trim = 0;
3123 u64 aligned_end = 0;
3124
3125 if (off > key.offset) {
3126 skip = off - key.offset;
3127 new_key.offset += skip;
3128 }
3129
3130 if (key.offset + datal > off + len)
3131 trim = key.offset + datal - (off + len);
3132
3133 if (comp && (skip || trim)) {
3134 ret = -EINVAL;
3135 btrfs_end_transaction(trans, root);
3136 goto out;
3137 }
3138 size -= skip + trim;
3139 datal -= skip + trim;
3140
3141 aligned_end = ALIGN(new_key.offset + datal,
3142 root->sectorsize);
3143 ret = btrfs_drop_extents(trans, root, inode,
3144 new_key.offset,
3145 aligned_end,
3146 1);
3147 if (ret) {
3148 if (ret != -EOPNOTSUPP)
3149 btrfs_abort_transaction(trans,
3150 root, ret);
3151 btrfs_end_transaction(trans, root);
3152 goto out;
3153 }
3154
3155 ret = btrfs_insert_empty_item(trans, root, path,
3156 &new_key, size);
3157 if (ret) {
3158 btrfs_abort_transaction(trans, root,
3159 ret);
3160 btrfs_end_transaction(trans, root);
3161 goto out;
3162 }
3163
3164 if (skip) {
3165 u32 start =
3166 btrfs_file_extent_calc_inline_size(0);
3167 memmove(buf+start, buf+start+skip,
3168 datal);
3169 }
3170
3171 leaf = path->nodes[0];
3172 slot = path->slots[0];
3173 write_extent_buffer(leaf, buf,
3174 btrfs_item_ptr_offset(leaf, slot),
3175 size);
3176 inode_add_bytes(inode, datal);
3177 }
3178
3179 btrfs_mark_buffer_dirty(leaf);
3180 btrfs_release_path(path);
3181
3182 inode_inc_iversion(inode);
3183 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3184
3185 /*
3186 * we round up to the block size at eof when
3187 * determining which extents to clone above,
3188 * but shouldn't round up the file size
3189 */
3190 endoff = new_key.offset + datal;
3191 if (endoff > destoff+olen)
3192 endoff = destoff+olen;
3193 if (endoff > inode->i_size)
3194 btrfs_i_size_write(inode, endoff);
3195
3196 ret = btrfs_update_inode(trans, root, inode);
3197 if (ret) {
3198 btrfs_abort_transaction(trans, root, ret);
3199 btrfs_end_transaction(trans, root);
3200 goto out;
3201 }
3202 ret = btrfs_end_transaction(trans, root);
3203 }
3204 btrfs_release_path(path);
3205 key.offset++;
3206 }
3207 ret = 0;
3208
3209out:
3210 btrfs_release_path(path);
3211 btrfs_free_path(path);
3212 vfree(buf);
3213 return ret;
3214}
3215
3216static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
3217 u64 off, u64 olen, u64 destoff)
3218{
3219 struct inode *inode = file_inode(file);
3220 struct btrfs_root *root = BTRFS_I(inode)->root;
3221 struct fd src_file;
3222 struct inode *src;
3223 int ret;
3224 u64 len = olen;
3225 u64 bs = root->fs_info->sb->s_blocksize;
3226 int same_inode = 0;
3227
3228 /*
3229 * TODO:
3230 * - split compressed inline extents. annoying: we need to
3231 * decompress into destination's address_space (the file offset
3232 * may change, so source mapping won't do), then recompress (or
3233 * otherwise reinsert) a subrange.
3234 *
3235 * - split destination inode's inline extents. The inline extents can
3236 * be either compressed or non-compressed.
3237 */
3238
3239 /* the destination must be opened for writing */
3240 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
3241 return -EINVAL;
3242
3243 if (btrfs_root_readonly(root))
3244 return -EROFS;
3245
3246 ret = mnt_want_write_file(file);
3247 if (ret)
3248 return ret;
3249
3250 src_file = fdget(srcfd);
3251 if (!src_file.file) {
3252 ret = -EBADF;
3253 goto out_drop_write;
3254 }
3255
3256 ret = -EXDEV;
3257 if (src_file.file->f_path.mnt != file->f_path.mnt)
3258 goto out_fput;
3259
3260 src = file_inode(src_file.file);
3261
3262 ret = -EINVAL;
3263 if (src == inode)
3264 same_inode = 1;
3265
3266 /* the src must be open for reading */
3267 if (!(src_file.file->f_mode & FMODE_READ))
3268 goto out_fput;
3269
3270 /* don't make the dst file partly checksummed */
3271 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3272 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3273 goto out_fput;
3274
3275 ret = -EISDIR;
3276 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3277 goto out_fput;
3278
3279 ret = -EXDEV;
3280 if (src->i_sb != inode->i_sb)
3281 goto out_fput;
3282
3283 if (!same_inode) {
3284 if (inode < src) {
3285 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
3286 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
3287 } else {
3288 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
3289 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
3290 }
3291 } else {
3292 mutex_lock(&src->i_mutex);
3293 }
3294
3295 /* determine range to clone */
3296 ret = -EINVAL;
3297 if (off + len > src->i_size || off + len < off)
3298 goto out_unlock;
3299 if (len == 0)
3300 olen = len = src->i_size - off;
3301 /* if we extend to eof, continue to block boundary */
3302 if (off + len == src->i_size)
3303 len = ALIGN(src->i_size, bs) - off;
3304
3305 /* verify the end result is block aligned */
3306 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
3307 !IS_ALIGNED(destoff, bs))
3308 goto out_unlock;
3309
3310 /* verify if ranges are overlapped within the same file */
3311 if (same_inode) {
3312 if (destoff + len > off && destoff < off + len)
3313 goto out_unlock;
3314 }
3315
3316 if (destoff > inode->i_size) {
3317 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3318 if (ret)
3319 goto out_unlock;
3320 }
3321
3322 /* truncate page cache pages from target inode range */
3323 truncate_inode_pages_range(&inode->i_data, destoff,
3324 PAGE_CACHE_ALIGN(destoff + len) - 1);
3325
3326 lock_extent_range(src, off, len);
3327
3328 ret = btrfs_clone(src, inode, off, olen, len, destoff);
3329
3330 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
3331out_unlock:
3332 if (!same_inode) {
3333 if (inode < src) {
3334 mutex_unlock(&src->i_mutex);
3335 mutex_unlock(&inode->i_mutex);
3336 } else {
3337 mutex_unlock(&inode->i_mutex);
3338 mutex_unlock(&src->i_mutex);
3339 }
3340 } else {
3341 mutex_unlock(&src->i_mutex);
3342 }
3343out_fput:
3344 fdput(src_file);
3345out_drop_write:
3346 mnt_drop_write_file(file);
3347 return ret;
3348}
3349
3350static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3351{
3352 struct btrfs_ioctl_clone_range_args args;
3353
3354 if (copy_from_user(&args, argp, sizeof(args)))
3355 return -EFAULT;
3356 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
3357 args.src_length, args.dest_offset);
3358}
3359
3360/*
3361 * there are many ways the trans_start and trans_end ioctls can lead
3362 * to deadlocks. They should only be used by applications that
3363 * basically own the machine, and have a very in depth understanding
3364 * of all the possible deadlocks and enospc problems.
3365 */
3366static long btrfs_ioctl_trans_start(struct file *file)
3367{
3368 struct inode *inode = file_inode(file);
3369 struct btrfs_root *root = BTRFS_I(inode)->root;
3370 struct btrfs_trans_handle *trans;
3371 int ret;
3372
3373 ret = -EPERM;
3374 if (!capable(CAP_SYS_ADMIN))
3375 goto out;
3376
3377 ret = -EINPROGRESS;
3378 if (file->private_data)
3379 goto out;
3380
3381 ret = -EROFS;
3382 if (btrfs_root_readonly(root))
3383 goto out;
3384
3385 ret = mnt_want_write_file(file);
3386 if (ret)
3387 goto out;
3388
3389 atomic_inc(&root->fs_info->open_ioctl_trans);
3390
3391 ret = -ENOMEM;
3392 trans = btrfs_start_ioctl_transaction(root);
3393 if (IS_ERR(trans))
3394 goto out_drop;
3395
3396 file->private_data = trans;
3397 return 0;
3398
3399out_drop:
3400 atomic_dec(&root->fs_info->open_ioctl_trans);
3401 mnt_drop_write_file(file);
3402out:
3403 return ret;
3404}
3405
3406static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3407{
3408 struct inode *inode = file_inode(file);
3409 struct btrfs_root *root = BTRFS_I(inode)->root;
3410 struct btrfs_root *new_root;
3411 struct btrfs_dir_item *di;
3412 struct btrfs_trans_handle *trans;
3413 struct btrfs_path *path;
3414 struct btrfs_key location;
3415 struct btrfs_disk_key disk_key;
3416 u64 objectid = 0;
3417 u64 dir_id;
3418 int ret;
3419
3420 if (!capable(CAP_SYS_ADMIN))
3421 return -EPERM;
3422
3423 ret = mnt_want_write_file(file);
3424 if (ret)
3425 return ret;
3426
3427 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3428 ret = -EFAULT;
3429 goto out;
3430 }
3431
3432 if (!objectid)
3433 objectid = BTRFS_FS_TREE_OBJECTID;
3434
3435 location.objectid = objectid;
3436 location.type = BTRFS_ROOT_ITEM_KEY;
3437 location.offset = (u64)-1;
3438
3439 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
3440 if (IS_ERR(new_root)) {
3441 ret = PTR_ERR(new_root);
3442 goto out;
3443 }
3444
3445 path = btrfs_alloc_path();
3446 if (!path) {
3447 ret = -ENOMEM;
3448 goto out;
3449 }
3450 path->leave_spinning = 1;
3451
3452 trans = btrfs_start_transaction(root, 1);
3453 if (IS_ERR(trans)) {
3454 btrfs_free_path(path);
3455 ret = PTR_ERR(trans);
3456 goto out;
3457 }
3458
3459 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3460 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
3461 dir_id, "default", 7, 1);
3462 if (IS_ERR_OR_NULL(di)) {
3463 btrfs_free_path(path);
3464 btrfs_end_transaction(trans, root);
3465 btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
3466 "item, this isn't going to work");
3467 ret = -ENOENT;
3468 goto out;
3469 }
3470
3471 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3472 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3473 btrfs_mark_buffer_dirty(path->nodes[0]);
3474 btrfs_free_path(path);
3475
3476 btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
3477 btrfs_end_transaction(trans, root);
3478out:
3479 mnt_drop_write_file(file);
3480 return ret;
3481}
3482
3483void btrfs_get_block_group_info(struct list_head *groups_list,
3484 struct btrfs_ioctl_space_info *space)
3485{
3486 struct btrfs_block_group_cache *block_group;
3487
3488 space->total_bytes = 0;
3489 space->used_bytes = 0;
3490 space->flags = 0;
3491 list_for_each_entry(block_group, groups_list, list) {
3492 space->flags = block_group->flags;
3493 space->total_bytes += block_group->key.offset;
3494 space->used_bytes +=
3495 btrfs_block_group_used(&block_group->item);
3496 }
3497}
3498
3499static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
3500{
3501 struct btrfs_ioctl_space_args space_args;
3502 struct btrfs_ioctl_space_info space;
3503 struct btrfs_ioctl_space_info *dest;
3504 struct btrfs_ioctl_space_info *dest_orig;
3505 struct btrfs_ioctl_space_info __user *user_dest;
3506 struct btrfs_space_info *info;
3507 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3508 BTRFS_BLOCK_GROUP_SYSTEM,
3509 BTRFS_BLOCK_GROUP_METADATA,
3510 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3511 int num_types = 4;
3512 int alloc_size;
3513 int ret = 0;
3514 u64 slot_count = 0;
3515 int i, c;
3516
3517 if (copy_from_user(&space_args,
3518 (struct btrfs_ioctl_space_args __user *)arg,
3519 sizeof(space_args)))
3520 return -EFAULT;
3521
3522 for (i = 0; i < num_types; i++) {
3523 struct btrfs_space_info *tmp;
3524
3525 info = NULL;
3526 rcu_read_lock();
3527 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3528 list) {
3529 if (tmp->flags == types[i]) {
3530 info = tmp;
3531 break;
3532 }
3533 }
3534 rcu_read_unlock();
3535
3536 if (!info)
3537 continue;
3538
3539 down_read(&info->groups_sem);
3540 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3541 if (!list_empty(&info->block_groups[c]))
3542 slot_count++;
3543 }
3544 up_read(&info->groups_sem);
3545 }
3546
3547 /*
3548 * Global block reserve, exported as a space_info
3549 */
3550 slot_count++;
3551
3552 /* space_slots == 0 means they are asking for a count */
3553 if (space_args.space_slots == 0) {
3554 space_args.total_spaces = slot_count;
3555 goto out;
3556 }
3557
3558 slot_count = min_t(u64, space_args.space_slots, slot_count);
3559
3560 alloc_size = sizeof(*dest) * slot_count;
3561
3562 /* we generally have at most 6 or so space infos, one for each raid
3563 * level. So, a whole page should be more than enough for everyone
3564 */
3565 if (alloc_size > PAGE_CACHE_SIZE)
3566 return -ENOMEM;
3567
3568 space_args.total_spaces = 0;
3569 dest = kmalloc(alloc_size, GFP_NOFS);
3570 if (!dest)
3571 return -ENOMEM;
3572 dest_orig = dest;
3573
3574 /* now we have a buffer to copy into */
3575 for (i = 0; i < num_types; i++) {
3576 struct btrfs_space_info *tmp;
3577
3578 if (!slot_count)
3579 break;
3580
3581 info = NULL;
3582 rcu_read_lock();
3583 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3584 list) {
3585 if (tmp->flags == types[i]) {
3586 info = tmp;
3587 break;
3588 }
3589 }
3590 rcu_read_unlock();
3591
3592 if (!info)
3593 continue;
3594 down_read(&info->groups_sem);
3595 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3596 if (!list_empty(&info->block_groups[c])) {
3597 btrfs_get_block_group_info(
3598 &info->block_groups[c], &space);
3599 memcpy(dest, &space, sizeof(space));
3600 dest++;
3601 space_args.total_spaces++;
3602 slot_count--;
3603 }
3604 if (!slot_count)
3605 break;
3606 }
3607 up_read(&info->groups_sem);
3608 }
3609
3610 /*
3611 * Add global block reserve
3612 */
3613 if (slot_count) {
3614 struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv;
3615
3616 spin_lock(&block_rsv->lock);
3617 space.total_bytes = block_rsv->size;
3618 space.used_bytes = block_rsv->size - block_rsv->reserved;
3619 spin_unlock(&block_rsv->lock);
3620 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
3621 memcpy(dest, &space, sizeof(space));
3622 space_args.total_spaces++;
3623 }
3624
3625 user_dest = (struct btrfs_ioctl_space_info __user *)
3626 (arg + sizeof(struct btrfs_ioctl_space_args));
3627
3628 if (copy_to_user(user_dest, dest_orig, alloc_size))
3629 ret = -EFAULT;
3630
3631 kfree(dest_orig);
3632out:
3633 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
3634 ret = -EFAULT;
3635
3636 return ret;
3637}
3638
3639/*
3640 * there are many ways the trans_start and trans_end ioctls can lead
3641 * to deadlocks. They should only be used by applications that
3642 * basically own the machine, and have a very in depth understanding
3643 * of all the possible deadlocks and enospc problems.
3644 */
3645long btrfs_ioctl_trans_end(struct file *file)
3646{
3647 struct inode *inode = file_inode(file);
3648 struct btrfs_root *root = BTRFS_I(inode)->root;
3649 struct btrfs_trans_handle *trans;
3650
3651 trans = file->private_data;
3652 if (!trans)
3653 return -EINVAL;
3654 file->private_data = NULL;
3655
3656 btrfs_end_transaction(trans, root);
3657
3658 atomic_dec(&root->fs_info->open_ioctl_trans);
3659
3660 mnt_drop_write_file(file);
3661 return 0;
3662}
3663
3664static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
3665 void __user *argp)
3666{
3667 struct btrfs_trans_handle *trans;
3668 u64 transid;
3669 int ret;
3670
3671 trans = btrfs_attach_transaction_barrier(root);
3672 if (IS_ERR(trans)) {
3673 if (PTR_ERR(trans) != -ENOENT)
3674 return PTR_ERR(trans);
3675
3676 /* No running transaction, don't bother */
3677 transid = root->fs_info->last_trans_committed;
3678 goto out;
3679 }
3680 transid = trans->transid;
3681 ret = btrfs_commit_transaction_async(trans, root, 0);
3682 if (ret) {
3683 btrfs_end_transaction(trans, root);
3684 return ret;
3685 }
3686out:
3687 if (argp)
3688 if (copy_to_user(argp, &transid, sizeof(transid)))
3689 return -EFAULT;
3690 return 0;
3691}
3692
3693static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
3694 void __user *argp)
3695{
3696 u64 transid;
3697
3698 if (argp) {
3699 if (copy_from_user(&transid, argp, sizeof(transid)))
3700 return -EFAULT;
3701 } else {
3702 transid = 0; /* current trans */
3703 }
3704 return btrfs_wait_for_commit(root, transid);
3705}
3706
3707static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
3708{
3709 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3710 struct btrfs_ioctl_scrub_args *sa;
3711 int ret;
3712
3713 if (!capable(CAP_SYS_ADMIN))
3714 return -EPERM;
3715
3716 sa = memdup_user(arg, sizeof(*sa));
3717 if (IS_ERR(sa))
3718 return PTR_ERR(sa);
3719
3720 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
3721 ret = mnt_want_write_file(file);
3722 if (ret)
3723 goto out;
3724 }
3725
3726 ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
3727 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
3728 0);
3729
3730 if (copy_to_user(arg, sa, sizeof(*sa)))
3731 ret = -EFAULT;
3732
3733 if (!(sa->flags & BTRFS_SCRUB_READONLY))
3734 mnt_drop_write_file(file);
3735out:
3736 kfree(sa);
3737 return ret;
3738}
3739
3740static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
3741{
3742 if (!capable(CAP_SYS_ADMIN))
3743 return -EPERM;
3744
3745 return btrfs_scrub_cancel(root->fs_info);
3746}
3747
3748static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
3749 void __user *arg)
3750{
3751 struct btrfs_ioctl_scrub_args *sa;
3752 int ret;
3753
3754 if (!capable(CAP_SYS_ADMIN))
3755 return -EPERM;
3756
3757 sa = memdup_user(arg, sizeof(*sa));
3758 if (IS_ERR(sa))
3759 return PTR_ERR(sa);
3760
3761 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
3762
3763 if (copy_to_user(arg, sa, sizeof(*sa)))
3764 ret = -EFAULT;
3765
3766 kfree(sa);
3767 return ret;
3768}
3769
3770static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
3771 void __user *arg)
3772{
3773 struct btrfs_ioctl_get_dev_stats *sa;
3774 int ret;
3775
3776 sa = memdup_user(arg, sizeof(*sa));
3777 if (IS_ERR(sa))
3778 return PTR_ERR(sa);
3779
3780 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3781 kfree(sa);
3782 return -EPERM;
3783 }
3784
3785 ret = btrfs_get_dev_stats(root, sa);
3786
3787 if (copy_to_user(arg, sa, sizeof(*sa)))
3788 ret = -EFAULT;
3789
3790 kfree(sa);
3791 return ret;
3792}
3793
3794static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
3795{
3796 struct btrfs_ioctl_dev_replace_args *p;
3797 int ret;
3798
3799 if (!capable(CAP_SYS_ADMIN))
3800 return -EPERM;
3801
3802 p = memdup_user(arg, sizeof(*p));
3803 if (IS_ERR(p))
3804 return PTR_ERR(p);
3805
3806 switch (p->cmd) {
3807 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3808 if (root->fs_info->sb->s_flags & MS_RDONLY) {
3809 ret = -EROFS;
3810 goto out;
3811 }
3812 if (atomic_xchg(
3813 &root->fs_info->mutually_exclusive_operation_running,
3814 1)) {
3815 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3816 } else {
3817 ret = btrfs_dev_replace_start(root, p);
3818 atomic_set(
3819 &root->fs_info->mutually_exclusive_operation_running,
3820 0);
3821 }
3822 break;
3823 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
3824 btrfs_dev_replace_status(root->fs_info, p);
3825 ret = 0;
3826 break;
3827 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
3828 ret = btrfs_dev_replace_cancel(root->fs_info, p);
3829 break;
3830 default:
3831 ret = -EINVAL;
3832 break;
3833 }
3834
3835 if (copy_to_user(arg, p, sizeof(*p)))
3836 ret = -EFAULT;
3837out:
3838 kfree(p);
3839 return ret;
3840}
3841
3842static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3843{
3844 int ret = 0;
3845 int i;
3846 u64 rel_ptr;
3847 int size;
3848 struct btrfs_ioctl_ino_path_args *ipa = NULL;
3849 struct inode_fs_paths *ipath = NULL;
3850 struct btrfs_path *path;
3851
3852 if (!capable(CAP_DAC_READ_SEARCH))
3853 return -EPERM;
3854
3855 path = btrfs_alloc_path();
3856 if (!path) {
3857 ret = -ENOMEM;
3858 goto out;
3859 }
3860
3861 ipa = memdup_user(arg, sizeof(*ipa));
3862 if (IS_ERR(ipa)) {
3863 ret = PTR_ERR(ipa);
3864 ipa = NULL;
3865 goto out;
3866 }
3867
3868 size = min_t(u32, ipa->size, 4096);
3869 ipath = init_ipath(size, root, path);
3870 if (IS_ERR(ipath)) {
3871 ret = PTR_ERR(ipath);
3872 ipath = NULL;
3873 goto out;
3874 }
3875
3876 ret = paths_from_inode(ipa->inum, ipath);
3877 if (ret < 0)
3878 goto out;
3879
3880 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3881 rel_ptr = ipath->fspath->val[i] -
3882 (u64)(unsigned long)ipath->fspath->val;
3883 ipath->fspath->val[i] = rel_ptr;
3884 }
3885
3886 ret = copy_to_user((void *)(unsigned long)ipa->fspath,
3887 (void *)(unsigned long)ipath->fspath, size);
3888 if (ret) {
3889 ret = -EFAULT;
3890 goto out;
3891 }
3892
3893out:
3894 btrfs_free_path(path);
3895 free_ipath(ipath);
3896 kfree(ipa);
3897
3898 return ret;
3899}
3900
3901static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3902{
3903 struct btrfs_data_container *inodes = ctx;
3904 const size_t c = 3 * sizeof(u64);
3905
3906 if (inodes->bytes_left >= c) {
3907 inodes->bytes_left -= c;
3908 inodes->val[inodes->elem_cnt] = inum;
3909 inodes->val[inodes->elem_cnt + 1] = offset;
3910 inodes->val[inodes->elem_cnt + 2] = root;
3911 inodes->elem_cnt += 3;
3912 } else {
3913 inodes->bytes_missing += c - inodes->bytes_left;
3914 inodes->bytes_left = 0;
3915 inodes->elem_missed += 3;
3916 }
3917
3918 return 0;
3919}
3920
3921static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
3922 void __user *arg)
3923{
3924 int ret = 0;
3925 int size;
3926 struct btrfs_ioctl_logical_ino_args *loi;
3927 struct btrfs_data_container *inodes = NULL;
3928 struct btrfs_path *path = NULL;
3929
3930 if (!capable(CAP_SYS_ADMIN))
3931 return -EPERM;
3932
3933 loi = memdup_user(arg, sizeof(*loi));
3934 if (IS_ERR(loi)) {
3935 ret = PTR_ERR(loi);
3936 loi = NULL;
3937 goto out;
3938 }
3939
3940 path = btrfs_alloc_path();
3941 if (!path) {
3942 ret = -ENOMEM;
3943 goto out;
3944 }
3945
3946 size = min_t(u32, loi->size, 64 * 1024);
3947 inodes = init_data_container(size);
3948 if (IS_ERR(inodes)) {
3949 ret = PTR_ERR(inodes);
3950 inodes = NULL;
3951 goto out;
3952 }
3953
3954 ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
3955 build_ino_list, inodes);
3956 if (ret == -EINVAL)
3957 ret = -ENOENT;
3958 if (ret < 0)
3959 goto out;
3960
3961 ret = copy_to_user((void *)(unsigned long)loi->inodes,
3962 (void *)(unsigned long)inodes, size);
3963 if (ret)
3964 ret = -EFAULT;
3965
3966out:
3967 btrfs_free_path(path);
3968 vfree(inodes);
3969 kfree(loi);
3970
3971 return ret;
3972}
3973
3974void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
3975 struct btrfs_ioctl_balance_args *bargs)
3976{
3977 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3978
3979 bargs->flags = bctl->flags;
3980
3981 if (atomic_read(&fs_info->balance_running))
3982 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3983 if (atomic_read(&fs_info->balance_pause_req))
3984 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3985 if (atomic_read(&fs_info->balance_cancel_req))
3986 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3987
3988 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3989 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3990 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3991
3992 if (lock) {
3993 spin_lock(&fs_info->balance_lock);
3994 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3995 spin_unlock(&fs_info->balance_lock);
3996 } else {
3997 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3998 }
3999}
4000
4001static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4002{
4003 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4004 struct btrfs_fs_info *fs_info = root->fs_info;
4005 struct btrfs_ioctl_balance_args *bargs;
4006 struct btrfs_balance_control *bctl;
4007 bool need_unlock; /* for mut. excl. ops lock */
4008 int ret;
4009
4010 if (!capable(CAP_SYS_ADMIN))
4011 return -EPERM;
4012
4013 ret = mnt_want_write_file(file);
4014 if (ret)
4015 return ret;
4016
4017again:
4018 if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
4019 mutex_lock(&fs_info->volume_mutex);
4020 mutex_lock(&fs_info->balance_mutex);
4021 need_unlock = true;
4022 goto locked;
4023 }
4024
4025 /*
4026 * mut. excl. ops lock is locked. Three possibilites:
4027 * (1) some other op is running
4028 * (2) balance is running
4029 * (3) balance is paused -- special case (think resume)
4030 */
4031 mutex_lock(&fs_info->balance_mutex);
4032 if (fs_info->balance_ctl) {
4033 /* this is either (2) or (3) */
4034 if (!atomic_read(&fs_info->balance_running)) {
4035 mutex_unlock(&fs_info->balance_mutex);
4036 if (!mutex_trylock(&fs_info->volume_mutex))
4037 goto again;
4038 mutex_lock(&fs_info->balance_mutex);
4039
4040 if (fs_info->balance_ctl &&
4041 !atomic_read(&fs_info->balance_running)) {
4042 /* this is (3) */
4043 need_unlock = false;
4044 goto locked;
4045 }
4046
4047 mutex_unlock(&fs_info->balance_mutex);
4048 mutex_unlock(&fs_info->volume_mutex);
4049 goto again;
4050 } else {
4051 /* this is (2) */
4052 mutex_unlock(&fs_info->balance_mutex);
4053 ret = -EINPROGRESS;
4054 goto out;
4055 }
4056 } else {
4057 /* this is (1) */
4058 mutex_unlock(&fs_info->balance_mutex);
4059 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4060 goto out;
4061 }
4062
4063locked:
4064 BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4065
4066 if (arg) {
4067 bargs = memdup_user(arg, sizeof(*bargs));
4068 if (IS_ERR(bargs)) {
4069 ret = PTR_ERR(bargs);
4070 goto out_unlock;
4071 }
4072
4073 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4074 if (!fs_info->balance_ctl) {
4075 ret = -ENOTCONN;
4076 goto out_bargs;
4077 }
4078
4079 bctl = fs_info->balance_ctl;
4080 spin_lock(&fs_info->balance_lock);
4081 bctl->flags |= BTRFS_BALANCE_RESUME;
4082 spin_unlock(&fs_info->balance_lock);
4083
4084 goto do_balance;
4085 }
4086 } else {
4087 bargs = NULL;
4088 }
4089
4090 if (fs_info->balance_ctl) {
4091 ret = -EINPROGRESS;
4092 goto out_bargs;
4093 }
4094
4095 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
4096 if (!bctl) {
4097 ret = -ENOMEM;
4098 goto out_bargs;
4099 }
4100
4101 bctl->fs_info = fs_info;
4102 if (arg) {
4103 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4104 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4105 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4106
4107 bctl->flags = bargs->flags;
4108 } else {
4109 /* balance everything - no filters */
4110 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4111 }
4112
4113do_balance:
4114 /*
4115 * Ownership of bctl and mutually_exclusive_operation_running
4116 * goes to to btrfs_balance. bctl is freed in __cancel_balance,
4117 * or, if restriper was paused all the way until unmount, in
4118 * free_fs_info. mutually_exclusive_operation_running is
4119 * cleared in __cancel_balance.
4120 */
4121 need_unlock = false;
4122
4123 ret = btrfs_balance(bctl, bargs);
4124
4125 if (arg) {
4126 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4127 ret = -EFAULT;
4128 }
4129
4130out_bargs:
4131 kfree(bargs);
4132out_unlock:
4133 mutex_unlock(&fs_info->balance_mutex);
4134 mutex_unlock(&fs_info->volume_mutex);
4135 if (need_unlock)
4136 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
4137out:
4138 mnt_drop_write_file(file);
4139 return ret;
4140}
4141
4142static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
4143{
4144 if (!capable(CAP_SYS_ADMIN))
4145 return -EPERM;
4146
4147 switch (cmd) {
4148 case BTRFS_BALANCE_CTL_PAUSE:
4149 return btrfs_pause_balance(root->fs_info);
4150 case BTRFS_BALANCE_CTL_CANCEL:
4151 return btrfs_cancel_balance(root->fs_info);
4152 }
4153
4154 return -EINVAL;
4155}
4156
4157static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
4158 void __user *arg)
4159{
4160 struct btrfs_fs_info *fs_info = root->fs_info;
4161 struct btrfs_ioctl_balance_args *bargs;
4162 int ret = 0;
4163
4164 if (!capable(CAP_SYS_ADMIN))
4165 return -EPERM;
4166
4167 mutex_lock(&fs_info->balance_mutex);
4168 if (!fs_info->balance_ctl) {
4169 ret = -ENOTCONN;
4170 goto out;
4171 }
4172
4173 bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
4174 if (!bargs) {
4175 ret = -ENOMEM;
4176 goto out;
4177 }
4178
4179 update_ioctl_balance_args(fs_info, 1, bargs);
4180
4181 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4182 ret = -EFAULT;
4183
4184 kfree(bargs);
4185out:
4186 mutex_unlock(&fs_info->balance_mutex);
4187 return ret;
4188}
4189
4190static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4191{
4192 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4193 struct btrfs_ioctl_quota_ctl_args *sa;
4194 struct btrfs_trans_handle *trans = NULL;
4195 int ret;
4196 int err;
4197
4198 if (!capable(CAP_SYS_ADMIN))
4199 return -EPERM;
4200
4201 ret = mnt_want_write_file(file);
4202 if (ret)
4203 return ret;
4204
4205 sa = memdup_user(arg, sizeof(*sa));
4206 if (IS_ERR(sa)) {
4207 ret = PTR_ERR(sa);
4208 goto drop_write;
4209 }
4210
4211 down_write(&root->fs_info->subvol_sem);
4212 trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
4213 if (IS_ERR(trans)) {
4214 ret = PTR_ERR(trans);
4215 goto out;
4216 }
4217
4218 switch (sa->cmd) {
4219 case BTRFS_QUOTA_CTL_ENABLE:
4220 ret = btrfs_quota_enable(trans, root->fs_info);
4221 break;
4222 case BTRFS_QUOTA_CTL_DISABLE:
4223 ret = btrfs_quota_disable(trans, root->fs_info);
4224 break;
4225 default:
4226 ret = -EINVAL;
4227 break;
4228 }
4229
4230 err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
4231 if (err && !ret)
4232 ret = err;
4233out:
4234 kfree(sa);
4235 up_write(&root->fs_info->subvol_sem);
4236drop_write:
4237 mnt_drop_write_file(file);
4238 return ret;
4239}
4240
4241static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4242{
4243 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4244 struct btrfs_ioctl_qgroup_assign_args *sa;
4245 struct btrfs_trans_handle *trans;
4246 int ret;
4247 int err;
4248
4249 if (!capable(CAP_SYS_ADMIN))
4250 return -EPERM;
4251
4252 ret = mnt_want_write_file(file);
4253 if (ret)
4254 return ret;
4255
4256 sa = memdup_user(arg, sizeof(*sa));
4257 if (IS_ERR(sa)) {
4258 ret = PTR_ERR(sa);
4259 goto drop_write;
4260 }
4261
4262 trans = btrfs_join_transaction(root);
4263 if (IS_ERR(trans)) {
4264 ret = PTR_ERR(trans);
4265 goto out;
4266 }
4267
4268 /* FIXME: check if the IDs really exist */
4269 if (sa->assign) {
4270 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
4271 sa->src, sa->dst);
4272 } else {
4273 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
4274 sa->src, sa->dst);
4275 }
4276
4277 err = btrfs_end_transaction(trans, root);
4278 if (err && !ret)
4279 ret = err;
4280
4281out:
4282 kfree(sa);
4283drop_write:
4284 mnt_drop_write_file(file);
4285 return ret;
4286}
4287
4288static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4289{
4290 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4291 struct btrfs_ioctl_qgroup_create_args *sa;
4292 struct btrfs_trans_handle *trans;
4293 int ret;
4294 int err;
4295
4296 if (!capable(CAP_SYS_ADMIN))
4297 return -EPERM;
4298
4299 ret = mnt_want_write_file(file);
4300 if (ret)
4301 return ret;
4302
4303 sa = memdup_user(arg, sizeof(*sa));
4304 if (IS_ERR(sa)) {
4305 ret = PTR_ERR(sa);
4306 goto drop_write;
4307 }
4308
4309 if (!sa->qgroupid) {
4310 ret = -EINVAL;
4311 goto out;
4312 }
4313
4314 trans = btrfs_join_transaction(root);
4315 if (IS_ERR(trans)) {
4316 ret = PTR_ERR(trans);
4317 goto out;
4318 }
4319
4320 /* FIXME: check if the IDs really exist */
4321 if (sa->create) {
4322 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
4323 NULL);
4324 } else {
4325 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
4326 }
4327
4328 err = btrfs_end_transaction(trans, root);
4329 if (err && !ret)
4330 ret = err;
4331
4332out:
4333 kfree(sa);
4334drop_write:
4335 mnt_drop_write_file(file);
4336 return ret;
4337}
4338
4339static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4340{
4341 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4342 struct btrfs_ioctl_qgroup_limit_args *sa;
4343 struct btrfs_trans_handle *trans;
4344 int ret;
4345 int err;
4346 u64 qgroupid;
4347
4348 if (!capable(CAP_SYS_ADMIN))
4349 return -EPERM;
4350
4351 ret = mnt_want_write_file(file);
4352 if (ret)
4353 return ret;
4354
4355 sa = memdup_user(arg, sizeof(*sa));
4356 if (IS_ERR(sa)) {
4357 ret = PTR_ERR(sa);
4358 goto drop_write;
4359 }
4360
4361 trans = btrfs_join_transaction(root);
4362 if (IS_ERR(trans)) {
4363 ret = PTR_ERR(trans);
4364 goto out;
4365 }
4366
4367 qgroupid = sa->qgroupid;
4368 if (!qgroupid) {
4369 /* take the current subvol as qgroup */
4370 qgroupid = root->root_key.objectid;
4371 }
4372
4373 /* FIXME: check if the IDs really exist */
4374 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
4375
4376 err = btrfs_end_transaction(trans, root);
4377 if (err && !ret)
4378 ret = err;
4379
4380out:
4381 kfree(sa);
4382drop_write:
4383 mnt_drop_write_file(file);
4384 return ret;
4385}
4386
4387static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4388{
4389 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4390 struct btrfs_ioctl_quota_rescan_args *qsa;
4391 int ret;
4392
4393 if (!capable(CAP_SYS_ADMIN))
4394 return -EPERM;
4395
4396 ret = mnt_want_write_file(file);
4397 if (ret)
4398 return ret;
4399
4400 qsa = memdup_user(arg, sizeof(*qsa));
4401 if (IS_ERR(qsa)) {
4402 ret = PTR_ERR(qsa);
4403 goto drop_write;
4404 }
4405
4406 if (qsa->flags) {
4407 ret = -EINVAL;
4408 goto out;
4409 }
4410
4411 ret = btrfs_qgroup_rescan(root->fs_info);
4412
4413out:
4414 kfree(qsa);
4415drop_write:
4416 mnt_drop_write_file(file);
4417 return ret;
4418}
4419
4420static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
4421{
4422 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4423 struct btrfs_ioctl_quota_rescan_args *qsa;
4424 int ret = 0;
4425
4426 if (!capable(CAP_SYS_ADMIN))
4427 return -EPERM;
4428
4429 qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
4430 if (!qsa)
4431 return -ENOMEM;
4432
4433 if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4434 qsa->flags = 1;
4435 qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
4436 }
4437
4438 if (copy_to_user(arg, qsa, sizeof(*qsa)))
4439 ret = -EFAULT;
4440
4441 kfree(qsa);
4442 return ret;
4443}
4444
4445static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
4446{
4447 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4448
4449 if (!capable(CAP_SYS_ADMIN))
4450 return -EPERM;
4451
4452 return btrfs_qgroup_wait_for_completion(root->fs_info);
4453}
4454
4455static long _btrfs_ioctl_set_received_subvol(struct file *file,
4456 struct btrfs_ioctl_received_subvol_args *sa)
4457{
4458 struct inode *inode = file_inode(file);
4459 struct btrfs_root *root = BTRFS_I(inode)->root;
4460 struct btrfs_root_item *root_item = &root->root_item;
4461 struct btrfs_trans_handle *trans;
4462 struct timespec ct = CURRENT_TIME;
4463 int ret = 0;
4464 int received_uuid_changed;
4465
4466 if (!inode_owner_or_capable(inode))
4467 return -EPERM;
4468
4469 ret = mnt_want_write_file(file);
4470 if (ret < 0)
4471 return ret;
4472
4473 down_write(&root->fs_info->subvol_sem);
4474
4475 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
4476 ret = -EINVAL;
4477 goto out;
4478 }
4479
4480 if (btrfs_root_readonly(root)) {
4481 ret = -EROFS;
4482 goto out;
4483 }
4484
4485 /*
4486 * 1 - root item
4487 * 2 - uuid items (received uuid + subvol uuid)
4488 */
4489 trans = btrfs_start_transaction(root, 3);
4490 if (IS_ERR(trans)) {
4491 ret = PTR_ERR(trans);
4492 trans = NULL;
4493 goto out;
4494 }
4495
4496 sa->rtransid = trans->transid;
4497 sa->rtime.sec = ct.tv_sec;
4498 sa->rtime.nsec = ct.tv_nsec;
4499
4500 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4501 BTRFS_UUID_SIZE);
4502 if (received_uuid_changed &&
4503 !btrfs_is_empty_uuid(root_item->received_uuid))
4504 btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
4505 root_item->received_uuid,
4506 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4507 root->root_key.objectid);
4508 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4509 btrfs_set_root_stransid(root_item, sa->stransid);
4510 btrfs_set_root_rtransid(root_item, sa->rtransid);
4511 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4512 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4513 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4514 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4515
4516 ret = btrfs_update_root(trans, root->fs_info->tree_root,
4517 &root->root_key, &root->root_item);
4518 if (ret < 0) {
4519 btrfs_end_transaction(trans, root);
4520 goto out;
4521 }
4522 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4523 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
4524 sa->uuid,
4525 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4526 root->root_key.objectid);
4527 if (ret < 0 && ret != -EEXIST) {
4528 btrfs_abort_transaction(trans, root, ret);
4529 goto out;
4530 }
4531 }
4532 ret = btrfs_commit_transaction(trans, root);
4533 if (ret < 0) {
4534 btrfs_abort_transaction(trans, root, ret);
4535 goto out;
4536 }
4537
4538out:
4539 up_write(&root->fs_info->subvol_sem);
4540 mnt_drop_write_file(file);
4541 return ret;
4542}
4543
4544#ifdef CONFIG_64BIT
4545static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4546 void __user *arg)
4547{
4548 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4549 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4550 int ret = 0;
4551
4552 args32 = memdup_user(arg, sizeof(*args32));
4553 if (IS_ERR(args32)) {
4554 ret = PTR_ERR(args32);
4555 args32 = NULL;
4556 goto out;
4557 }
4558
4559 args64 = kmalloc(sizeof(*args64), GFP_NOFS);
4560 if (!args64) {
4561 ret = -ENOMEM;
4562 goto out;
4563 }
4564
4565 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4566 args64->stransid = args32->stransid;
4567 args64->rtransid = args32->rtransid;
4568 args64->stime.sec = args32->stime.sec;
4569 args64->stime.nsec = args32->stime.nsec;
4570 args64->rtime.sec = args32->rtime.sec;
4571 args64->rtime.nsec = args32->rtime.nsec;
4572 args64->flags = args32->flags;
4573
4574 ret = _btrfs_ioctl_set_received_subvol(file, args64);
4575 if (ret)
4576 goto out;
4577
4578 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4579 args32->stransid = args64->stransid;
4580 args32->rtransid = args64->rtransid;
4581 args32->stime.sec = args64->stime.sec;
4582 args32->stime.nsec = args64->stime.nsec;
4583 args32->rtime.sec = args64->rtime.sec;
4584 args32->rtime.nsec = args64->rtime.nsec;
4585 args32->flags = args64->flags;
4586
4587 ret = copy_to_user(arg, args32, sizeof(*args32));
4588 if (ret)
4589 ret = -EFAULT;
4590
4591out:
4592 kfree(args32);
4593 kfree(args64);
4594 return ret;
4595}
4596#endif
4597
4598static long btrfs_ioctl_set_received_subvol(struct file *file,
4599 void __user *arg)
4600{
4601 struct btrfs_ioctl_received_subvol_args *sa = NULL;
4602 int ret = 0;
4603
4604 sa = memdup_user(arg, sizeof(*sa));
4605 if (IS_ERR(sa)) {
4606 ret = PTR_ERR(sa);
4607 sa = NULL;
4608 goto out;
4609 }
4610
4611 ret = _btrfs_ioctl_set_received_subvol(file, sa);
4612
4613 if (ret)
4614 goto out;
4615
4616 ret = copy_to_user(arg, sa, sizeof(*sa));
4617 if (ret)
4618 ret = -EFAULT;
4619
4620out:
4621 kfree(sa);
4622 return ret;
4623}
4624
4625static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
4626{
4627 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4628 size_t len;
4629 int ret;
4630 char label[BTRFS_LABEL_SIZE];
4631
4632 spin_lock(&root->fs_info->super_lock);
4633 memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
4634 spin_unlock(&root->fs_info->super_lock);
4635
4636 len = strnlen(label, BTRFS_LABEL_SIZE);
4637
4638 if (len == BTRFS_LABEL_SIZE) {
4639 btrfs_warn(root->fs_info,
4640 "label is too long, return the first %zu bytes", --len);
4641 }
4642
4643 ret = copy_to_user(arg, label, len);
4644
4645 return ret ? -EFAULT : 0;
4646}
4647
4648static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
4649{
4650 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4651 struct btrfs_super_block *super_block = root->fs_info->super_copy;
4652 struct btrfs_trans_handle *trans;
4653 char label[BTRFS_LABEL_SIZE];
4654 int ret;
4655
4656 if (!capable(CAP_SYS_ADMIN))
4657 return -EPERM;
4658
4659 if (copy_from_user(label, arg, sizeof(label)))
4660 return -EFAULT;
4661
4662 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
4663 btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
4664 BTRFS_LABEL_SIZE - 1);
4665 return -EINVAL;
4666 }
4667
4668 ret = mnt_want_write_file(file);
4669 if (ret)
4670 return ret;
4671
4672 trans = btrfs_start_transaction(root, 0);
4673 if (IS_ERR(trans)) {
4674 ret = PTR_ERR(trans);
4675 goto out_unlock;
4676 }
4677
4678 spin_lock(&root->fs_info->super_lock);
4679 strcpy(super_block->label, label);
4680 spin_unlock(&root->fs_info->super_lock);
4681 ret = btrfs_commit_transaction(trans, root);
4682
4683out_unlock:
4684 mnt_drop_write_file(file);
4685 return ret;
4686}
4687
4688#define INIT_FEATURE_FLAGS(suffix) \
4689 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
4690 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
4691 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
4692
4693static int btrfs_ioctl_get_supported_features(struct file *file,
4694 void __user *arg)
4695{
4696 static struct btrfs_ioctl_feature_flags features[3] = {
4697 INIT_FEATURE_FLAGS(SUPP),
4698 INIT_FEATURE_FLAGS(SAFE_SET),
4699 INIT_FEATURE_FLAGS(SAFE_CLEAR)
4700 };
4701
4702 if (copy_to_user(arg, &features, sizeof(features)))
4703 return -EFAULT;
4704
4705 return 0;
4706}
4707
4708static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
4709{
4710 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4711 struct btrfs_super_block *super_block = root->fs_info->super_copy;
4712 struct btrfs_ioctl_feature_flags features;
4713
4714 features.compat_flags = btrfs_super_compat_flags(super_block);
4715 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
4716 features.incompat_flags = btrfs_super_incompat_flags(super_block);
4717
4718 if (copy_to_user(arg, &features, sizeof(features)))
4719 return -EFAULT;
4720
4721 return 0;
4722}
4723
4724static int check_feature_bits(struct btrfs_root *root,
4725 enum btrfs_feature_set set,
4726 u64 change_mask, u64 flags, u64 supported_flags,
4727 u64 safe_set, u64 safe_clear)
4728{
4729 const char *type = btrfs_feature_set_names[set];
4730 char *names;
4731 u64 disallowed, unsupported;
4732 u64 set_mask = flags & change_mask;
4733 u64 clear_mask = ~flags & change_mask;
4734
4735 unsupported = set_mask & ~supported_flags;
4736 if (unsupported) {
4737 names = btrfs_printable_features(set, unsupported);
4738 if (names) {
4739 btrfs_warn(root->fs_info,
4740 "this kernel does not support the %s feature bit%s",
4741 names, strchr(names, ',') ? "s" : "");
4742 kfree(names);
4743 } else
4744 btrfs_warn(root->fs_info,
4745 "this kernel does not support %s bits 0x%llx",
4746 type, unsupported);
4747 return -EOPNOTSUPP;
4748 }
4749
4750 disallowed = set_mask & ~safe_set;
4751 if (disallowed) {
4752 names = btrfs_printable_features(set, disallowed);
4753 if (names) {
4754 btrfs_warn(root->fs_info,
4755 "can't set the %s feature bit%s while mounted",
4756 names, strchr(names, ',') ? "s" : "");
4757 kfree(names);
4758 } else
4759 btrfs_warn(root->fs_info,
4760 "can't set %s bits 0x%llx while mounted",
4761 type, disallowed);
4762 return -EPERM;
4763 }
4764
4765 disallowed = clear_mask & ~safe_clear;
4766 if (disallowed) {
4767 names = btrfs_printable_features(set, disallowed);
4768 if (names) {
4769 btrfs_warn(root->fs_info,
4770 "can't clear the %s feature bit%s while mounted",
4771 names, strchr(names, ',') ? "s" : "");
4772 kfree(names);
4773 } else
4774 btrfs_warn(root->fs_info,
4775 "can't clear %s bits 0x%llx while mounted",
4776 type, disallowed);
4777 return -EPERM;
4778 }
4779
4780 return 0;
4781}
4782
4783#define check_feature(root, change_mask, flags, mask_base) \
4784check_feature_bits(root, FEAT_##mask_base, change_mask, flags, \
4785 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
4786 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
4787 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
4788
4789static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
4790{
4791 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4792 struct btrfs_super_block *super_block = root->fs_info->super_copy;
4793 struct btrfs_ioctl_feature_flags flags[2];
4794 struct btrfs_trans_handle *trans;
4795 u64 newflags;
4796 int ret;
4797
4798 if (!capable(CAP_SYS_ADMIN))
4799 return -EPERM;
4800
4801 if (copy_from_user(flags, arg, sizeof(flags)))
4802 return -EFAULT;
4803
4804 /* Nothing to do */
4805 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
4806 !flags[0].incompat_flags)
4807 return 0;
4808
4809 ret = check_feature(root, flags[0].compat_flags,
4810 flags[1].compat_flags, COMPAT);
4811 if (ret)
4812 return ret;
4813
4814 ret = check_feature(root, flags[0].compat_ro_flags,
4815 flags[1].compat_ro_flags, COMPAT_RO);
4816 if (ret)
4817 return ret;
4818
4819 ret = check_feature(root, flags[0].incompat_flags,
4820 flags[1].incompat_flags, INCOMPAT);
4821 if (ret)
4822 return ret;
4823
4824 trans = btrfs_start_transaction(root, 0);
4825 if (IS_ERR(trans))
4826 return PTR_ERR(trans);
4827
4828 spin_lock(&root->fs_info->super_lock);
4829 newflags = btrfs_super_compat_flags(super_block);
4830 newflags |= flags[0].compat_flags & flags[1].compat_flags;
4831 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
4832 btrfs_set_super_compat_flags(super_block, newflags);
4833
4834 newflags = btrfs_super_compat_ro_flags(super_block);
4835 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
4836 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
4837 btrfs_set_super_compat_ro_flags(super_block, newflags);
4838
4839 newflags = btrfs_super_incompat_flags(super_block);
4840 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
4841 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
4842 btrfs_set_super_incompat_flags(super_block, newflags);
4843 spin_unlock(&root->fs_info->super_lock);
4844
4845 return btrfs_commit_transaction(trans, root);
4846}
4847
4848long btrfs_ioctl(struct file *file, unsigned int
4849 cmd, unsigned long arg)
4850{
4851 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4852 void __user *argp = (void __user *)arg;
4853
4854 switch (cmd) {
4855 case FS_IOC_GETFLAGS:
4856 return btrfs_ioctl_getflags(file, argp);
4857 case FS_IOC_SETFLAGS:
4858 return btrfs_ioctl_setflags(file, argp);
4859 case FS_IOC_GETVERSION:
4860 return btrfs_ioctl_getversion(file, argp);
4861 case FITRIM:
4862 return btrfs_ioctl_fitrim(file, argp);
4863 case BTRFS_IOC_SNAP_CREATE:
4864 return btrfs_ioctl_snap_create(file, argp, 0);
4865 case BTRFS_IOC_SNAP_CREATE_V2:
4866 return btrfs_ioctl_snap_create_v2(file, argp, 0);
4867 case BTRFS_IOC_SUBVOL_CREATE:
4868 return btrfs_ioctl_snap_create(file, argp, 1);
4869 case BTRFS_IOC_SUBVOL_CREATE_V2:
4870 return btrfs_ioctl_snap_create_v2(file, argp, 1);
4871 case BTRFS_IOC_SNAP_DESTROY:
4872 return btrfs_ioctl_snap_destroy(file, argp);
4873 case BTRFS_IOC_SUBVOL_GETFLAGS:
4874 return btrfs_ioctl_subvol_getflags(file, argp);
4875 case BTRFS_IOC_SUBVOL_SETFLAGS:
4876 return btrfs_ioctl_subvol_setflags(file, argp);
4877 case BTRFS_IOC_DEFAULT_SUBVOL:
4878 return btrfs_ioctl_default_subvol(file, argp);
4879 case BTRFS_IOC_DEFRAG:
4880 return btrfs_ioctl_defrag(file, NULL);
4881 case BTRFS_IOC_DEFRAG_RANGE:
4882 return btrfs_ioctl_defrag(file, argp);
4883 case BTRFS_IOC_RESIZE:
4884 return btrfs_ioctl_resize(file, argp);
4885 case BTRFS_IOC_ADD_DEV:
4886 return btrfs_ioctl_add_dev(root, argp);
4887 case BTRFS_IOC_RM_DEV:
4888 return btrfs_ioctl_rm_dev(file, argp);
4889 case BTRFS_IOC_FS_INFO:
4890 return btrfs_ioctl_fs_info(root, argp);
4891 case BTRFS_IOC_DEV_INFO:
4892 return btrfs_ioctl_dev_info(root, argp);
4893 case BTRFS_IOC_BALANCE:
4894 return btrfs_ioctl_balance(file, NULL);
4895 case BTRFS_IOC_CLONE:
4896 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
4897 case BTRFS_IOC_CLONE_RANGE:
4898 return btrfs_ioctl_clone_range(file, argp);
4899 case BTRFS_IOC_TRANS_START:
4900 return btrfs_ioctl_trans_start(file);
4901 case BTRFS_IOC_TRANS_END:
4902 return btrfs_ioctl_trans_end(file);
4903 case BTRFS_IOC_TREE_SEARCH:
4904 return btrfs_ioctl_tree_search(file, argp);
4905 case BTRFS_IOC_INO_LOOKUP:
4906 return btrfs_ioctl_ino_lookup(file, argp);
4907 case BTRFS_IOC_INO_PATHS:
4908 return btrfs_ioctl_ino_to_path(root, argp);
4909 case BTRFS_IOC_LOGICAL_INO:
4910 return btrfs_ioctl_logical_to_ino(root, argp);
4911 case BTRFS_IOC_SPACE_INFO:
4912 return btrfs_ioctl_space_info(root, argp);
4913 case BTRFS_IOC_SYNC: {
4914 int ret;
4915
4916 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
4917 if (ret)
4918 return ret;
4919 ret = btrfs_sync_fs(file->f_dentry->d_sb, 1);
4920 return ret;
4921 }
4922 case BTRFS_IOC_START_SYNC:
4923 return btrfs_ioctl_start_sync(root, argp);
4924 case BTRFS_IOC_WAIT_SYNC:
4925 return btrfs_ioctl_wait_sync(root, argp);
4926 case BTRFS_IOC_SCRUB:
4927 return btrfs_ioctl_scrub(file, argp);
4928 case BTRFS_IOC_SCRUB_CANCEL:
4929 return btrfs_ioctl_scrub_cancel(root, argp);
4930 case BTRFS_IOC_SCRUB_PROGRESS:
4931 return btrfs_ioctl_scrub_progress(root, argp);
4932 case BTRFS_IOC_BALANCE_V2:
4933 return btrfs_ioctl_balance(file, argp);
4934 case BTRFS_IOC_BALANCE_CTL:
4935 return btrfs_ioctl_balance_ctl(root, arg);
4936 case BTRFS_IOC_BALANCE_PROGRESS:
4937 return btrfs_ioctl_balance_progress(root, argp);
4938 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
4939 return btrfs_ioctl_set_received_subvol(file, argp);
4940#ifdef CONFIG_64BIT
4941 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
4942 return btrfs_ioctl_set_received_subvol_32(file, argp);
4943#endif
4944 case BTRFS_IOC_SEND:
4945 return btrfs_ioctl_send(file, argp);
4946 case BTRFS_IOC_GET_DEV_STATS:
4947 return btrfs_ioctl_get_dev_stats(root, argp);
4948 case BTRFS_IOC_QUOTA_CTL:
4949 return btrfs_ioctl_quota_ctl(file, argp);
4950 case BTRFS_IOC_QGROUP_ASSIGN:
4951 return btrfs_ioctl_qgroup_assign(file, argp);
4952 case BTRFS_IOC_QGROUP_CREATE:
4953 return btrfs_ioctl_qgroup_create(file, argp);
4954 case BTRFS_IOC_QGROUP_LIMIT:
4955 return btrfs_ioctl_qgroup_limit(file, argp);
4956 case BTRFS_IOC_QUOTA_RESCAN:
4957 return btrfs_ioctl_quota_rescan(file, argp);
4958 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
4959 return btrfs_ioctl_quota_rescan_status(file, argp);
4960 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
4961 return btrfs_ioctl_quota_rescan_wait(file, argp);
4962 case BTRFS_IOC_DEV_REPLACE:
4963 return btrfs_ioctl_dev_replace(root, argp);
4964 case BTRFS_IOC_GET_FSLABEL:
4965 return btrfs_ioctl_get_fslabel(file, argp);
4966 case BTRFS_IOC_SET_FSLABEL:
4967 return btrfs_ioctl_set_fslabel(file, argp);
4968 case BTRFS_IOC_FILE_EXTENT_SAME:
4969 return btrfs_ioctl_file_extent_same(file, argp);
4970 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
4971 return btrfs_ioctl_get_supported_features(file, argp);
4972 case BTRFS_IOC_GET_FEATURES:
4973 return btrfs_ioctl_get_features(file, argp);
4974 case BTRFS_IOC_SET_FEATURES:
4975 return btrfs_ioctl_set_features(file, argp);
4976 }
4977
4978 return -ENOTTY;
4979}