Loading...
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/compat.h>
37#include <linux/bit_spinlock.h>
38#include <linux/security.h>
39#include <linux/xattr.h>
40#include <linux/vmalloc.h>
41#include <linux/slab.h>
42#include <linux/blkdev.h>
43#include <linux/uuid.h>
44#include <linux/btrfs.h>
45#include <linux/uaccess.h>
46#include "ctree.h"
47#include "disk-io.h"
48#include "transaction.h"
49#include "btrfs_inode.h"
50#include "print-tree.h"
51#include "volumes.h"
52#include "locking.h"
53#include "inode-map.h"
54#include "backref.h"
55#include "rcu-string.h"
56#include "send.h"
57#include "dev-replace.h"
58#include "props.h"
59#include "sysfs.h"
60#include "qgroup.h"
61#include "tree-log.h"
62#include "compression.h"
63
64#ifdef CONFIG_64BIT
65/* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
66 * structures are incorrect, as the timespec structure from userspace
67 * is 4 bytes too small. We define these alternatives here to teach
68 * the kernel about the 32-bit struct packing.
69 */
70struct btrfs_ioctl_timespec_32 {
71 __u64 sec;
72 __u32 nsec;
73} __attribute__ ((__packed__));
74
75struct btrfs_ioctl_received_subvol_args_32 {
76 char uuid[BTRFS_UUID_SIZE]; /* in */
77 __u64 stransid; /* in */
78 __u64 rtransid; /* out */
79 struct btrfs_ioctl_timespec_32 stime; /* in */
80 struct btrfs_ioctl_timespec_32 rtime; /* out */
81 __u64 flags; /* in */
82 __u64 reserved[16]; /* in */
83} __attribute__ ((__packed__));
84
85#define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
86 struct btrfs_ioctl_received_subvol_args_32)
87#endif
88
89
90static int btrfs_clone(struct inode *src, struct inode *inode,
91 u64 off, u64 olen, u64 olen_aligned, u64 destoff,
92 int no_time_update);
93
94/* Mask out flags that are inappropriate for the given type of inode. */
95static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
96{
97 if (S_ISDIR(mode))
98 return flags;
99 else if (S_ISREG(mode))
100 return flags & ~FS_DIRSYNC_FL;
101 else
102 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
103}
104
105/*
106 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
107 */
108static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
109{
110 unsigned int iflags = 0;
111
112 if (flags & BTRFS_INODE_SYNC)
113 iflags |= FS_SYNC_FL;
114 if (flags & BTRFS_INODE_IMMUTABLE)
115 iflags |= FS_IMMUTABLE_FL;
116 if (flags & BTRFS_INODE_APPEND)
117 iflags |= FS_APPEND_FL;
118 if (flags & BTRFS_INODE_NODUMP)
119 iflags |= FS_NODUMP_FL;
120 if (flags & BTRFS_INODE_NOATIME)
121 iflags |= FS_NOATIME_FL;
122 if (flags & BTRFS_INODE_DIRSYNC)
123 iflags |= FS_DIRSYNC_FL;
124 if (flags & BTRFS_INODE_NODATACOW)
125 iflags |= FS_NOCOW_FL;
126
127 if (flags & BTRFS_INODE_NOCOMPRESS)
128 iflags |= FS_NOCOMP_FL;
129 else if (flags & BTRFS_INODE_COMPRESS)
130 iflags |= FS_COMPR_FL;
131
132 return iflags;
133}
134
135/*
136 * Update inode->i_flags based on the btrfs internal flags.
137 */
138void btrfs_update_iflags(struct inode *inode)
139{
140 struct btrfs_inode *ip = BTRFS_I(inode);
141 unsigned int new_fl = 0;
142
143 if (ip->flags & BTRFS_INODE_SYNC)
144 new_fl |= S_SYNC;
145 if (ip->flags & BTRFS_INODE_IMMUTABLE)
146 new_fl |= S_IMMUTABLE;
147 if (ip->flags & BTRFS_INODE_APPEND)
148 new_fl |= S_APPEND;
149 if (ip->flags & BTRFS_INODE_NOATIME)
150 new_fl |= S_NOATIME;
151 if (ip->flags & BTRFS_INODE_DIRSYNC)
152 new_fl |= S_DIRSYNC;
153
154 set_mask_bits(&inode->i_flags,
155 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
156 new_fl);
157}
158
159/*
160 * Inherit flags from the parent inode.
161 *
162 * Currently only the compression flags and the cow flags are inherited.
163 */
164void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
165{
166 unsigned int flags;
167
168 if (!dir)
169 return;
170
171 flags = BTRFS_I(dir)->flags;
172
173 if (flags & BTRFS_INODE_NOCOMPRESS) {
174 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
175 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
176 } else if (flags & BTRFS_INODE_COMPRESS) {
177 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
178 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
179 }
180
181 if (flags & BTRFS_INODE_NODATACOW) {
182 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
183 if (S_ISREG(inode->i_mode))
184 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
185 }
186
187 btrfs_update_iflags(inode);
188}
189
190static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
191{
192 struct btrfs_inode *ip = BTRFS_I(file_inode(file));
193 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
194
195 if (copy_to_user(arg, &flags, sizeof(flags)))
196 return -EFAULT;
197 return 0;
198}
199
200static int check_flags(unsigned int flags)
201{
202 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
203 FS_NOATIME_FL | FS_NODUMP_FL | \
204 FS_SYNC_FL | FS_DIRSYNC_FL | \
205 FS_NOCOMP_FL | FS_COMPR_FL |
206 FS_NOCOW_FL))
207 return -EOPNOTSUPP;
208
209 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
210 return -EINVAL;
211
212 return 0;
213}
214
215static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
216{
217 struct inode *inode = file_inode(file);
218 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
219 struct btrfs_inode *ip = BTRFS_I(inode);
220 struct btrfs_root *root = ip->root;
221 struct btrfs_trans_handle *trans;
222 unsigned int flags, oldflags;
223 int ret;
224 u64 ip_oldflags;
225 unsigned int i_oldflags;
226 umode_t mode;
227
228 if (!inode_owner_or_capable(inode))
229 return -EPERM;
230
231 if (btrfs_root_readonly(root))
232 return -EROFS;
233
234 if (copy_from_user(&flags, arg, sizeof(flags)))
235 return -EFAULT;
236
237 ret = check_flags(flags);
238 if (ret)
239 return ret;
240
241 ret = mnt_want_write_file(file);
242 if (ret)
243 return ret;
244
245 inode_lock(inode);
246
247 ip_oldflags = ip->flags;
248 i_oldflags = inode->i_flags;
249 mode = inode->i_mode;
250
251 flags = btrfs_mask_flags(inode->i_mode, flags);
252 oldflags = btrfs_flags_to_ioctl(ip->flags);
253 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
254 if (!capable(CAP_LINUX_IMMUTABLE)) {
255 ret = -EPERM;
256 goto out_unlock;
257 }
258 }
259
260 if (flags & FS_SYNC_FL)
261 ip->flags |= BTRFS_INODE_SYNC;
262 else
263 ip->flags &= ~BTRFS_INODE_SYNC;
264 if (flags & FS_IMMUTABLE_FL)
265 ip->flags |= BTRFS_INODE_IMMUTABLE;
266 else
267 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
268 if (flags & FS_APPEND_FL)
269 ip->flags |= BTRFS_INODE_APPEND;
270 else
271 ip->flags &= ~BTRFS_INODE_APPEND;
272 if (flags & FS_NODUMP_FL)
273 ip->flags |= BTRFS_INODE_NODUMP;
274 else
275 ip->flags &= ~BTRFS_INODE_NODUMP;
276 if (flags & FS_NOATIME_FL)
277 ip->flags |= BTRFS_INODE_NOATIME;
278 else
279 ip->flags &= ~BTRFS_INODE_NOATIME;
280 if (flags & FS_DIRSYNC_FL)
281 ip->flags |= BTRFS_INODE_DIRSYNC;
282 else
283 ip->flags &= ~BTRFS_INODE_DIRSYNC;
284 if (flags & FS_NOCOW_FL) {
285 if (S_ISREG(mode)) {
286 /*
287 * It's safe to turn csums off here, no extents exist.
288 * Otherwise we want the flag to reflect the real COW
289 * status of the file and will not set it.
290 */
291 if (inode->i_size == 0)
292 ip->flags |= BTRFS_INODE_NODATACOW
293 | BTRFS_INODE_NODATASUM;
294 } else {
295 ip->flags |= BTRFS_INODE_NODATACOW;
296 }
297 } else {
298 /*
299 * Revert back under same assumptions as above
300 */
301 if (S_ISREG(mode)) {
302 if (inode->i_size == 0)
303 ip->flags &= ~(BTRFS_INODE_NODATACOW
304 | BTRFS_INODE_NODATASUM);
305 } else {
306 ip->flags &= ~BTRFS_INODE_NODATACOW;
307 }
308 }
309
310 /*
311 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
312 * flag may be changed automatically if compression code won't make
313 * things smaller.
314 */
315 if (flags & FS_NOCOMP_FL) {
316 ip->flags &= ~BTRFS_INODE_COMPRESS;
317 ip->flags |= BTRFS_INODE_NOCOMPRESS;
318
319 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
320 if (ret && ret != -ENODATA)
321 goto out_drop;
322 } else if (flags & FS_COMPR_FL) {
323 const char *comp;
324
325 ip->flags |= BTRFS_INODE_COMPRESS;
326 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
327
328 if (fs_info->compress_type == BTRFS_COMPRESS_LZO)
329 comp = "lzo";
330 else
331 comp = "zlib";
332 ret = btrfs_set_prop(inode, "btrfs.compression",
333 comp, strlen(comp), 0);
334 if (ret)
335 goto out_drop;
336
337 } else {
338 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
339 if (ret && ret != -ENODATA)
340 goto out_drop;
341 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
342 }
343
344 trans = btrfs_start_transaction(root, 1);
345 if (IS_ERR(trans)) {
346 ret = PTR_ERR(trans);
347 goto out_drop;
348 }
349
350 btrfs_update_iflags(inode);
351 inode_inc_iversion(inode);
352 inode->i_ctime = current_time(inode);
353 ret = btrfs_update_inode(trans, root, inode);
354
355 btrfs_end_transaction(trans);
356 out_drop:
357 if (ret) {
358 ip->flags = ip_oldflags;
359 inode->i_flags = i_oldflags;
360 }
361
362 out_unlock:
363 inode_unlock(inode);
364 mnt_drop_write_file(file);
365 return ret;
366}
367
368static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
369{
370 struct inode *inode = file_inode(file);
371
372 return put_user(inode->i_generation, arg);
373}
374
375static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
376{
377 struct inode *inode = file_inode(file);
378 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
379 struct btrfs_device *device;
380 struct request_queue *q;
381 struct fstrim_range range;
382 u64 minlen = ULLONG_MAX;
383 u64 num_devices = 0;
384 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
385 int ret;
386
387 if (!capable(CAP_SYS_ADMIN))
388 return -EPERM;
389
390 rcu_read_lock();
391 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
392 dev_list) {
393 if (!device->bdev)
394 continue;
395 q = bdev_get_queue(device->bdev);
396 if (blk_queue_discard(q)) {
397 num_devices++;
398 minlen = min((u64)q->limits.discard_granularity,
399 minlen);
400 }
401 }
402 rcu_read_unlock();
403
404 if (!num_devices)
405 return -EOPNOTSUPP;
406 if (copy_from_user(&range, arg, sizeof(range)))
407 return -EFAULT;
408 if (range.start > total_bytes ||
409 range.len < fs_info->sb->s_blocksize)
410 return -EINVAL;
411
412 range.len = min(range.len, total_bytes - range.start);
413 range.minlen = max(range.minlen, minlen);
414 ret = btrfs_trim_fs(fs_info, &range);
415 if (ret < 0)
416 return ret;
417
418 if (copy_to_user(arg, &range, sizeof(range)))
419 return -EFAULT;
420
421 return 0;
422}
423
424int btrfs_is_empty_uuid(u8 *uuid)
425{
426 int i;
427
428 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
429 if (uuid[i])
430 return 0;
431 }
432 return 1;
433}
434
435static noinline int create_subvol(struct inode *dir,
436 struct dentry *dentry,
437 char *name, int namelen,
438 u64 *async_transid,
439 struct btrfs_qgroup_inherit *inherit)
440{
441 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
442 struct btrfs_trans_handle *trans;
443 struct btrfs_key key;
444 struct btrfs_root_item *root_item;
445 struct btrfs_inode_item *inode_item;
446 struct extent_buffer *leaf;
447 struct btrfs_root *root = BTRFS_I(dir)->root;
448 struct btrfs_root *new_root;
449 struct btrfs_block_rsv block_rsv;
450 struct timespec cur_time = current_time(dir);
451 struct inode *inode;
452 int ret;
453 int err;
454 u64 objectid;
455 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
456 u64 index = 0;
457 u64 qgroup_reserved;
458 uuid_le new_uuid;
459
460 root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
461 if (!root_item)
462 return -ENOMEM;
463
464 ret = btrfs_find_free_objectid(fs_info->tree_root, &objectid);
465 if (ret)
466 goto fail_free;
467
468 /*
469 * Don't create subvolume whose level is not zero. Or qgroup will be
470 * screwed up since it assumes subvolume qgroup's level to be 0.
471 */
472 if (btrfs_qgroup_level(objectid)) {
473 ret = -ENOSPC;
474 goto fail_free;
475 }
476
477 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
478 /*
479 * The same as the snapshot creation, please see the comment
480 * of create_snapshot().
481 */
482 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
483 8, &qgroup_reserved, false);
484 if (ret)
485 goto fail_free;
486
487 trans = btrfs_start_transaction(root, 0);
488 if (IS_ERR(trans)) {
489 ret = PTR_ERR(trans);
490 btrfs_subvolume_release_metadata(fs_info, &block_rsv,
491 qgroup_reserved);
492 goto fail_free;
493 }
494 trans->block_rsv = &block_rsv;
495 trans->bytes_reserved = block_rsv.size;
496
497 ret = btrfs_qgroup_inherit(trans, fs_info, 0, objectid, inherit);
498 if (ret)
499 goto fail;
500
501 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
502 if (IS_ERR(leaf)) {
503 ret = PTR_ERR(leaf);
504 goto fail;
505 }
506
507 memzero_extent_buffer(leaf, 0, sizeof(struct btrfs_header));
508 btrfs_set_header_bytenr(leaf, leaf->start);
509 btrfs_set_header_generation(leaf, trans->transid);
510 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
511 btrfs_set_header_owner(leaf, objectid);
512
513 write_extent_buffer_fsid(leaf, fs_info->fsid);
514 write_extent_buffer_chunk_tree_uuid(leaf, fs_info->chunk_tree_uuid);
515 btrfs_mark_buffer_dirty(leaf);
516
517 inode_item = &root_item->inode;
518 btrfs_set_stack_inode_generation(inode_item, 1);
519 btrfs_set_stack_inode_size(inode_item, 3);
520 btrfs_set_stack_inode_nlink(inode_item, 1);
521 btrfs_set_stack_inode_nbytes(inode_item,
522 fs_info->nodesize);
523 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
524
525 btrfs_set_root_flags(root_item, 0);
526 btrfs_set_root_limit(root_item, 0);
527 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
528
529 btrfs_set_root_bytenr(root_item, leaf->start);
530 btrfs_set_root_generation(root_item, trans->transid);
531 btrfs_set_root_level(root_item, 0);
532 btrfs_set_root_refs(root_item, 1);
533 btrfs_set_root_used(root_item, leaf->len);
534 btrfs_set_root_last_snapshot(root_item, 0);
535
536 btrfs_set_root_generation_v2(root_item,
537 btrfs_root_generation(root_item));
538 uuid_le_gen(&new_uuid);
539 memcpy(root_item->uuid, new_uuid.b, BTRFS_UUID_SIZE);
540 btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);
541 btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);
542 root_item->ctime = root_item->otime;
543 btrfs_set_root_ctransid(root_item, trans->transid);
544 btrfs_set_root_otransid(root_item, trans->transid);
545
546 btrfs_tree_unlock(leaf);
547 free_extent_buffer(leaf);
548 leaf = NULL;
549
550 btrfs_set_root_dirid(root_item, new_dirid);
551
552 key.objectid = objectid;
553 key.offset = 0;
554 key.type = BTRFS_ROOT_ITEM_KEY;
555 ret = btrfs_insert_root(trans, fs_info->tree_root, &key,
556 root_item);
557 if (ret)
558 goto fail;
559
560 key.offset = (u64)-1;
561 new_root = btrfs_read_fs_root_no_name(fs_info, &key);
562 if (IS_ERR(new_root)) {
563 ret = PTR_ERR(new_root);
564 btrfs_abort_transaction(trans, ret);
565 goto fail;
566 }
567
568 btrfs_record_root_in_trans(trans, new_root);
569
570 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
571 if (ret) {
572 /* We potentially lose an unused inode item here */
573 btrfs_abort_transaction(trans, ret);
574 goto fail;
575 }
576
577 mutex_lock(&new_root->objectid_mutex);
578 new_root->highest_objectid = new_dirid;
579 mutex_unlock(&new_root->objectid_mutex);
580
581 /*
582 * insert the directory item
583 */
584 ret = btrfs_set_inode_index(dir, &index);
585 if (ret) {
586 btrfs_abort_transaction(trans, ret);
587 goto fail;
588 }
589
590 ret = btrfs_insert_dir_item(trans, root,
591 name, namelen, dir, &key,
592 BTRFS_FT_DIR, index);
593 if (ret) {
594 btrfs_abort_transaction(trans, ret);
595 goto fail;
596 }
597
598 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
599 ret = btrfs_update_inode(trans, root, dir);
600 BUG_ON(ret);
601
602 ret = btrfs_add_root_ref(trans, fs_info,
603 objectid, root->root_key.objectid,
604 btrfs_ino(dir), index, name, namelen);
605 BUG_ON(ret);
606
607 ret = btrfs_uuid_tree_add(trans, fs_info, root_item->uuid,
608 BTRFS_UUID_KEY_SUBVOL, objectid);
609 if (ret)
610 btrfs_abort_transaction(trans, ret);
611
612fail:
613 kfree(root_item);
614 trans->block_rsv = NULL;
615 trans->bytes_reserved = 0;
616 btrfs_subvolume_release_metadata(fs_info, &block_rsv, qgroup_reserved);
617
618 if (async_transid) {
619 *async_transid = trans->transid;
620 err = btrfs_commit_transaction_async(trans, 1);
621 if (err)
622 err = btrfs_commit_transaction(trans);
623 } else {
624 err = btrfs_commit_transaction(trans);
625 }
626 if (err && !ret)
627 ret = err;
628
629 if (!ret) {
630 inode = btrfs_lookup_dentry(dir, dentry);
631 if (IS_ERR(inode))
632 return PTR_ERR(inode);
633 d_instantiate(dentry, inode);
634 }
635 return ret;
636
637fail_free:
638 kfree(root_item);
639 return ret;
640}
641
642static void btrfs_wait_for_no_snapshoting_writes(struct btrfs_root *root)
643{
644 s64 writers;
645 DEFINE_WAIT(wait);
646
647 do {
648 prepare_to_wait(&root->subv_writers->wait, &wait,
649 TASK_UNINTERRUPTIBLE);
650
651 writers = percpu_counter_sum(&root->subv_writers->counter);
652 if (writers)
653 schedule();
654
655 finish_wait(&root->subv_writers->wait, &wait);
656 } while (writers);
657}
658
659static int create_snapshot(struct btrfs_root *root, struct inode *dir,
660 struct dentry *dentry, char *name, int namelen,
661 u64 *async_transid, bool readonly,
662 struct btrfs_qgroup_inherit *inherit)
663{
664 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
665 struct inode *inode;
666 struct btrfs_pending_snapshot *pending_snapshot;
667 struct btrfs_trans_handle *trans;
668 int ret;
669
670 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
671 return -EINVAL;
672
673 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
674 if (!pending_snapshot)
675 return -ENOMEM;
676
677 pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
678 GFP_NOFS);
679 pending_snapshot->path = btrfs_alloc_path();
680 if (!pending_snapshot->root_item || !pending_snapshot->path) {
681 ret = -ENOMEM;
682 goto free_pending;
683 }
684
685 atomic_inc(&root->will_be_snapshoted);
686 smp_mb__after_atomic();
687 btrfs_wait_for_no_snapshoting_writes(root);
688
689 ret = btrfs_start_delalloc_inodes(root, 0);
690 if (ret)
691 goto dec_and_free;
692
693 btrfs_wait_ordered_extents(root, -1, 0, (u64)-1);
694
695 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
696 BTRFS_BLOCK_RSV_TEMP);
697 /*
698 * 1 - parent dir inode
699 * 2 - dir entries
700 * 1 - root item
701 * 2 - root ref/backref
702 * 1 - root of snapshot
703 * 1 - UUID item
704 */
705 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
706 &pending_snapshot->block_rsv, 8,
707 &pending_snapshot->qgroup_reserved,
708 false);
709 if (ret)
710 goto dec_and_free;
711
712 pending_snapshot->dentry = dentry;
713 pending_snapshot->root = root;
714 pending_snapshot->readonly = readonly;
715 pending_snapshot->dir = dir;
716 pending_snapshot->inherit = inherit;
717
718 trans = btrfs_start_transaction(root, 0);
719 if (IS_ERR(trans)) {
720 ret = PTR_ERR(trans);
721 goto fail;
722 }
723
724 spin_lock(&fs_info->trans_lock);
725 list_add(&pending_snapshot->list,
726 &trans->transaction->pending_snapshots);
727 spin_unlock(&fs_info->trans_lock);
728 if (async_transid) {
729 *async_transid = trans->transid;
730 ret = btrfs_commit_transaction_async(trans, 1);
731 if (ret)
732 ret = btrfs_commit_transaction(trans);
733 } else {
734 ret = btrfs_commit_transaction(trans);
735 }
736 if (ret)
737 goto fail;
738
739 ret = pending_snapshot->error;
740 if (ret)
741 goto fail;
742
743 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
744 if (ret)
745 goto fail;
746
747 inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
748 if (IS_ERR(inode)) {
749 ret = PTR_ERR(inode);
750 goto fail;
751 }
752
753 d_instantiate(dentry, inode);
754 ret = 0;
755fail:
756 btrfs_subvolume_release_metadata(fs_info,
757 &pending_snapshot->block_rsv,
758 pending_snapshot->qgroup_reserved);
759dec_and_free:
760 if (atomic_dec_and_test(&root->will_be_snapshoted))
761 wake_up_atomic_t(&root->will_be_snapshoted);
762free_pending:
763 kfree(pending_snapshot->root_item);
764 btrfs_free_path(pending_snapshot->path);
765 kfree(pending_snapshot);
766
767 return ret;
768}
769
770/* copy of may_delete in fs/namei.c()
771 * Check whether we can remove a link victim from directory dir, check
772 * whether the type of victim is right.
773 * 1. We can't do it if dir is read-only (done in permission())
774 * 2. We should have write and exec permissions on dir
775 * 3. We can't remove anything from append-only dir
776 * 4. We can't do anything with immutable dir (done in permission())
777 * 5. If the sticky bit on dir is set we should either
778 * a. be owner of dir, or
779 * b. be owner of victim, or
780 * c. have CAP_FOWNER capability
781 * 6. If the victim is append-only or immutable we can't do anything with
782 * links pointing to it.
783 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
784 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
785 * 9. We can't remove a root or mountpoint.
786 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
787 * nfs_async_unlink().
788 */
789
790static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
791{
792 int error;
793
794 if (d_really_is_negative(victim))
795 return -ENOENT;
796
797 BUG_ON(d_inode(victim->d_parent) != dir);
798 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
799
800 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
801 if (error)
802 return error;
803 if (IS_APPEND(dir))
804 return -EPERM;
805 if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
806 IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
807 return -EPERM;
808 if (isdir) {
809 if (!d_is_dir(victim))
810 return -ENOTDIR;
811 if (IS_ROOT(victim))
812 return -EBUSY;
813 } else if (d_is_dir(victim))
814 return -EISDIR;
815 if (IS_DEADDIR(dir))
816 return -ENOENT;
817 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
818 return -EBUSY;
819 return 0;
820}
821
822/* copy of may_create in fs/namei.c() */
823static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
824{
825 if (d_really_is_positive(child))
826 return -EEXIST;
827 if (IS_DEADDIR(dir))
828 return -ENOENT;
829 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
830}
831
832/*
833 * Create a new subvolume below @parent. This is largely modeled after
834 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
835 * inside this filesystem so it's quite a bit simpler.
836 */
837static noinline int btrfs_mksubvol(const struct path *parent,
838 char *name, int namelen,
839 struct btrfs_root *snap_src,
840 u64 *async_transid, bool readonly,
841 struct btrfs_qgroup_inherit *inherit)
842{
843 struct inode *dir = d_inode(parent->dentry);
844 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
845 struct dentry *dentry;
846 int error;
847
848 error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
849 if (error == -EINTR)
850 return error;
851
852 dentry = lookup_one_len(name, parent->dentry, namelen);
853 error = PTR_ERR(dentry);
854 if (IS_ERR(dentry))
855 goto out_unlock;
856
857 error = btrfs_may_create(dir, dentry);
858 if (error)
859 goto out_dput;
860
861 /*
862 * even if this name doesn't exist, we may get hash collisions.
863 * check for them now when we can safely fail
864 */
865 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
866 dir->i_ino, name,
867 namelen);
868 if (error)
869 goto out_dput;
870
871 down_read(&fs_info->subvol_sem);
872
873 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
874 goto out_up_read;
875
876 if (snap_src) {
877 error = create_snapshot(snap_src, dir, dentry, name, namelen,
878 async_transid, readonly, inherit);
879 } else {
880 error = create_subvol(dir, dentry, name, namelen,
881 async_transid, inherit);
882 }
883 if (!error)
884 fsnotify_mkdir(dir, dentry);
885out_up_read:
886 up_read(&fs_info->subvol_sem);
887out_dput:
888 dput(dentry);
889out_unlock:
890 inode_unlock(dir);
891 return error;
892}
893
894/*
895 * When we're defragging a range, we don't want to kick it off again
896 * if it is really just waiting for delalloc to send it down.
897 * If we find a nice big extent or delalloc range for the bytes in the
898 * file you want to defrag, we return 0 to let you know to skip this
899 * part of the file
900 */
901static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
902{
903 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
904 struct extent_map *em = NULL;
905 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
906 u64 end;
907
908 read_lock(&em_tree->lock);
909 em = lookup_extent_mapping(em_tree, offset, PAGE_SIZE);
910 read_unlock(&em_tree->lock);
911
912 if (em) {
913 end = extent_map_end(em);
914 free_extent_map(em);
915 if (end - offset > thresh)
916 return 0;
917 }
918 /* if we already have a nice delalloc here, just stop */
919 thresh /= 2;
920 end = count_range_bits(io_tree, &offset, offset + thresh,
921 thresh, EXTENT_DELALLOC, 1);
922 if (end >= thresh)
923 return 0;
924 return 1;
925}
926
927/*
928 * helper function to walk through a file and find extents
929 * newer than a specific transid, and smaller than thresh.
930 *
931 * This is used by the defragging code to find new and small
932 * extents
933 */
934static int find_new_extents(struct btrfs_root *root,
935 struct inode *inode, u64 newer_than,
936 u64 *off, u32 thresh)
937{
938 struct btrfs_path *path;
939 struct btrfs_key min_key;
940 struct extent_buffer *leaf;
941 struct btrfs_file_extent_item *extent;
942 int type;
943 int ret;
944 u64 ino = btrfs_ino(inode);
945
946 path = btrfs_alloc_path();
947 if (!path)
948 return -ENOMEM;
949
950 min_key.objectid = ino;
951 min_key.type = BTRFS_EXTENT_DATA_KEY;
952 min_key.offset = *off;
953
954 while (1) {
955 ret = btrfs_search_forward(root, &min_key, path, newer_than);
956 if (ret != 0)
957 goto none;
958process_slot:
959 if (min_key.objectid != ino)
960 goto none;
961 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
962 goto none;
963
964 leaf = path->nodes[0];
965 extent = btrfs_item_ptr(leaf, path->slots[0],
966 struct btrfs_file_extent_item);
967
968 type = btrfs_file_extent_type(leaf, extent);
969 if (type == BTRFS_FILE_EXTENT_REG &&
970 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
971 check_defrag_in_cache(inode, min_key.offset, thresh)) {
972 *off = min_key.offset;
973 btrfs_free_path(path);
974 return 0;
975 }
976
977 path->slots[0]++;
978 if (path->slots[0] < btrfs_header_nritems(leaf)) {
979 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
980 goto process_slot;
981 }
982
983 if (min_key.offset == (u64)-1)
984 goto none;
985
986 min_key.offset++;
987 btrfs_release_path(path);
988 }
989none:
990 btrfs_free_path(path);
991 return -ENOENT;
992}
993
994static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
995{
996 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
997 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
998 struct extent_map *em;
999 u64 len = PAGE_SIZE;
1000
1001 /*
1002 * hopefully we have this extent in the tree already, try without
1003 * the full extent lock
1004 */
1005 read_lock(&em_tree->lock);
1006 em = lookup_extent_mapping(em_tree, start, len);
1007 read_unlock(&em_tree->lock);
1008
1009 if (!em) {
1010 struct extent_state *cached = NULL;
1011 u64 end = start + len - 1;
1012
1013 /* get the big lock and read metadata off disk */
1014 lock_extent_bits(io_tree, start, end, &cached);
1015 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
1016 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
1017
1018 if (IS_ERR(em))
1019 return NULL;
1020 }
1021
1022 return em;
1023}
1024
1025static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1026{
1027 struct extent_map *next;
1028 bool ret = true;
1029
1030 /* this is the last extent */
1031 if (em->start + em->len >= i_size_read(inode))
1032 return false;
1033
1034 next = defrag_lookup_extent(inode, em->start + em->len);
1035 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1036 ret = false;
1037 else if ((em->block_start + em->block_len == next->block_start) &&
1038 (em->block_len > SZ_128K && next->block_len > SZ_128K))
1039 ret = false;
1040
1041 free_extent_map(next);
1042 return ret;
1043}
1044
1045static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1046 u64 *last_len, u64 *skip, u64 *defrag_end,
1047 int compress)
1048{
1049 struct extent_map *em;
1050 int ret = 1;
1051 bool next_mergeable = true;
1052 bool prev_mergeable = true;
1053
1054 /*
1055 * make sure that once we start defragging an extent, we keep on
1056 * defragging it
1057 */
1058 if (start < *defrag_end)
1059 return 1;
1060
1061 *skip = 0;
1062
1063 em = defrag_lookup_extent(inode, start);
1064 if (!em)
1065 return 0;
1066
1067 /* this will cover holes, and inline extents */
1068 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1069 ret = 0;
1070 goto out;
1071 }
1072
1073 if (!*defrag_end)
1074 prev_mergeable = false;
1075
1076 next_mergeable = defrag_check_next_extent(inode, em);
1077 /*
1078 * we hit a real extent, if it is big or the next extent is not a
1079 * real extent, don't bother defragging it
1080 */
1081 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1082 (em->len >= thresh || (!next_mergeable && !prev_mergeable)))
1083 ret = 0;
1084out:
1085 /*
1086 * last_len ends up being a counter of how many bytes we've defragged.
1087 * every time we choose not to defrag an extent, we reset *last_len
1088 * so that the next tiny extent will force a defrag.
1089 *
1090 * The end result of this is that tiny extents before a single big
1091 * extent will force at least part of that big extent to be defragged.
1092 */
1093 if (ret) {
1094 *defrag_end = extent_map_end(em);
1095 } else {
1096 *last_len = 0;
1097 *skip = extent_map_end(em);
1098 *defrag_end = 0;
1099 }
1100
1101 free_extent_map(em);
1102 return ret;
1103}
1104
1105/*
1106 * it doesn't do much good to defrag one or two pages
1107 * at a time. This pulls in a nice chunk of pages
1108 * to COW and defrag.
1109 *
1110 * It also makes sure the delalloc code has enough
1111 * dirty data to avoid making new small extents as part
1112 * of the defrag
1113 *
1114 * It's a good idea to start RA on this range
1115 * before calling this.
1116 */
1117static int cluster_pages_for_defrag(struct inode *inode,
1118 struct page **pages,
1119 unsigned long start_index,
1120 unsigned long num_pages)
1121{
1122 unsigned long file_end;
1123 u64 isize = i_size_read(inode);
1124 u64 page_start;
1125 u64 page_end;
1126 u64 page_cnt;
1127 int ret;
1128 int i;
1129 int i_done;
1130 struct btrfs_ordered_extent *ordered;
1131 struct extent_state *cached_state = NULL;
1132 struct extent_io_tree *tree;
1133 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1134
1135 file_end = (isize - 1) >> PAGE_SHIFT;
1136 if (!isize || start_index > file_end)
1137 return 0;
1138
1139 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1140
1141 ret = btrfs_delalloc_reserve_space(inode,
1142 start_index << PAGE_SHIFT,
1143 page_cnt << PAGE_SHIFT);
1144 if (ret)
1145 return ret;
1146 i_done = 0;
1147 tree = &BTRFS_I(inode)->io_tree;
1148
1149 /* step one, lock all the pages */
1150 for (i = 0; i < page_cnt; i++) {
1151 struct page *page;
1152again:
1153 page = find_or_create_page(inode->i_mapping,
1154 start_index + i, mask);
1155 if (!page)
1156 break;
1157
1158 page_start = page_offset(page);
1159 page_end = page_start + PAGE_SIZE - 1;
1160 while (1) {
1161 lock_extent_bits(tree, page_start, page_end,
1162 &cached_state);
1163 ordered = btrfs_lookup_ordered_extent(inode,
1164 page_start);
1165 unlock_extent_cached(tree, page_start, page_end,
1166 &cached_state, GFP_NOFS);
1167 if (!ordered)
1168 break;
1169
1170 unlock_page(page);
1171 btrfs_start_ordered_extent(inode, ordered, 1);
1172 btrfs_put_ordered_extent(ordered);
1173 lock_page(page);
1174 /*
1175 * we unlocked the page above, so we need check if
1176 * it was released or not.
1177 */
1178 if (page->mapping != inode->i_mapping) {
1179 unlock_page(page);
1180 put_page(page);
1181 goto again;
1182 }
1183 }
1184
1185 if (!PageUptodate(page)) {
1186 btrfs_readpage(NULL, page);
1187 lock_page(page);
1188 if (!PageUptodate(page)) {
1189 unlock_page(page);
1190 put_page(page);
1191 ret = -EIO;
1192 break;
1193 }
1194 }
1195
1196 if (page->mapping != inode->i_mapping) {
1197 unlock_page(page);
1198 put_page(page);
1199 goto again;
1200 }
1201
1202 pages[i] = page;
1203 i_done++;
1204 }
1205 if (!i_done || ret)
1206 goto out;
1207
1208 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1209 goto out;
1210
1211 /*
1212 * so now we have a nice long stream of locked
1213 * and up to date pages, lets wait on them
1214 */
1215 for (i = 0; i < i_done; i++)
1216 wait_on_page_writeback(pages[i]);
1217
1218 page_start = page_offset(pages[0]);
1219 page_end = page_offset(pages[i_done - 1]) + PAGE_SIZE;
1220
1221 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1222 page_start, page_end - 1, &cached_state);
1223 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1224 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1225 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1226 &cached_state, GFP_NOFS);
1227
1228 if (i_done != page_cnt) {
1229 spin_lock(&BTRFS_I(inode)->lock);
1230 BTRFS_I(inode)->outstanding_extents++;
1231 spin_unlock(&BTRFS_I(inode)->lock);
1232 btrfs_delalloc_release_space(inode,
1233 start_index << PAGE_SHIFT,
1234 (page_cnt - i_done) << PAGE_SHIFT);
1235 }
1236
1237
1238 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1239 &cached_state);
1240
1241 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1242 page_start, page_end - 1, &cached_state,
1243 GFP_NOFS);
1244
1245 for (i = 0; i < i_done; i++) {
1246 clear_page_dirty_for_io(pages[i]);
1247 ClearPageChecked(pages[i]);
1248 set_page_extent_mapped(pages[i]);
1249 set_page_dirty(pages[i]);
1250 unlock_page(pages[i]);
1251 put_page(pages[i]);
1252 }
1253 return i_done;
1254out:
1255 for (i = 0; i < i_done; i++) {
1256 unlock_page(pages[i]);
1257 put_page(pages[i]);
1258 }
1259 btrfs_delalloc_release_space(inode,
1260 start_index << PAGE_SHIFT,
1261 page_cnt << PAGE_SHIFT);
1262 return ret;
1263
1264}
1265
1266int btrfs_defrag_file(struct inode *inode, struct file *file,
1267 struct btrfs_ioctl_defrag_range_args *range,
1268 u64 newer_than, unsigned long max_to_defrag)
1269{
1270 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1271 struct btrfs_root *root = BTRFS_I(inode)->root;
1272 struct file_ra_state *ra = NULL;
1273 unsigned long last_index;
1274 u64 isize = i_size_read(inode);
1275 u64 last_len = 0;
1276 u64 skip = 0;
1277 u64 defrag_end = 0;
1278 u64 newer_off = range->start;
1279 unsigned long i;
1280 unsigned long ra_index = 0;
1281 int ret;
1282 int defrag_count = 0;
1283 int compress_type = BTRFS_COMPRESS_ZLIB;
1284 u32 extent_thresh = range->extent_thresh;
1285 unsigned long max_cluster = SZ_256K >> PAGE_SHIFT;
1286 unsigned long cluster = max_cluster;
1287 u64 new_align = ~((u64)SZ_128K - 1);
1288 struct page **pages = NULL;
1289
1290 if (isize == 0)
1291 return 0;
1292
1293 if (range->start >= isize)
1294 return -EINVAL;
1295
1296 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1297 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1298 return -EINVAL;
1299 if (range->compress_type)
1300 compress_type = range->compress_type;
1301 }
1302
1303 if (extent_thresh == 0)
1304 extent_thresh = SZ_256K;
1305
1306 /*
1307 * if we were not given a file, allocate a readahead
1308 * context
1309 */
1310 if (!file) {
1311 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1312 if (!ra)
1313 return -ENOMEM;
1314 file_ra_state_init(ra, inode->i_mapping);
1315 } else {
1316 ra = &file->f_ra;
1317 }
1318
1319 pages = kmalloc_array(max_cluster, sizeof(struct page *),
1320 GFP_NOFS);
1321 if (!pages) {
1322 ret = -ENOMEM;
1323 goto out_ra;
1324 }
1325
1326 /* find the last page to defrag */
1327 if (range->start + range->len > range->start) {
1328 last_index = min_t(u64, isize - 1,
1329 range->start + range->len - 1) >> PAGE_SHIFT;
1330 } else {
1331 last_index = (isize - 1) >> PAGE_SHIFT;
1332 }
1333
1334 if (newer_than) {
1335 ret = find_new_extents(root, inode, newer_than,
1336 &newer_off, SZ_64K);
1337 if (!ret) {
1338 range->start = newer_off;
1339 /*
1340 * we always align our defrag to help keep
1341 * the extents in the file evenly spaced
1342 */
1343 i = (newer_off & new_align) >> PAGE_SHIFT;
1344 } else
1345 goto out_ra;
1346 } else {
1347 i = range->start >> PAGE_SHIFT;
1348 }
1349 if (!max_to_defrag)
1350 max_to_defrag = last_index - i + 1;
1351
1352 /*
1353 * make writeback starts from i, so the defrag range can be
1354 * written sequentially.
1355 */
1356 if (i < inode->i_mapping->writeback_index)
1357 inode->i_mapping->writeback_index = i;
1358
1359 while (i <= last_index && defrag_count < max_to_defrag &&
1360 (i < DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE))) {
1361 /*
1362 * make sure we stop running if someone unmounts
1363 * the FS
1364 */
1365 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1366 break;
1367
1368 if (btrfs_defrag_cancelled(fs_info)) {
1369 btrfs_debug(fs_info, "defrag_file cancelled");
1370 ret = -EAGAIN;
1371 break;
1372 }
1373
1374 if (!should_defrag_range(inode, (u64)i << PAGE_SHIFT,
1375 extent_thresh, &last_len, &skip,
1376 &defrag_end, range->flags &
1377 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1378 unsigned long next;
1379 /*
1380 * the should_defrag function tells us how much to skip
1381 * bump our counter by the suggested amount
1382 */
1383 next = DIV_ROUND_UP(skip, PAGE_SIZE);
1384 i = max(i + 1, next);
1385 continue;
1386 }
1387
1388 if (!newer_than) {
1389 cluster = (PAGE_ALIGN(defrag_end) >>
1390 PAGE_SHIFT) - i;
1391 cluster = min(cluster, max_cluster);
1392 } else {
1393 cluster = max_cluster;
1394 }
1395
1396 if (i + cluster > ra_index) {
1397 ra_index = max(i, ra_index);
1398 btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1399 cluster);
1400 ra_index += cluster;
1401 }
1402
1403 inode_lock(inode);
1404 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1405 BTRFS_I(inode)->force_compress = compress_type;
1406 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1407 if (ret < 0) {
1408 inode_unlock(inode);
1409 goto out_ra;
1410 }
1411
1412 defrag_count += ret;
1413 balance_dirty_pages_ratelimited(inode->i_mapping);
1414 inode_unlock(inode);
1415
1416 if (newer_than) {
1417 if (newer_off == (u64)-1)
1418 break;
1419
1420 if (ret > 0)
1421 i += ret;
1422
1423 newer_off = max(newer_off + 1,
1424 (u64)i << PAGE_SHIFT);
1425
1426 ret = find_new_extents(root, inode, newer_than,
1427 &newer_off, SZ_64K);
1428 if (!ret) {
1429 range->start = newer_off;
1430 i = (newer_off & new_align) >> PAGE_SHIFT;
1431 } else {
1432 break;
1433 }
1434 } else {
1435 if (ret > 0) {
1436 i += ret;
1437 last_len += ret << PAGE_SHIFT;
1438 } else {
1439 i++;
1440 last_len = 0;
1441 }
1442 }
1443 }
1444
1445 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1446 filemap_flush(inode->i_mapping);
1447 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1448 &BTRFS_I(inode)->runtime_flags))
1449 filemap_flush(inode->i_mapping);
1450 }
1451
1452 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1453 /* the filemap_flush will queue IO into the worker threads, but
1454 * we have to make sure the IO is actually started and that
1455 * ordered extents get created before we return
1456 */
1457 atomic_inc(&fs_info->async_submit_draining);
1458 while (atomic_read(&fs_info->nr_async_submits) ||
1459 atomic_read(&fs_info->async_delalloc_pages)) {
1460 wait_event(fs_info->async_submit_wait,
1461 (atomic_read(&fs_info->nr_async_submits) == 0 &&
1462 atomic_read(&fs_info->async_delalloc_pages) == 0));
1463 }
1464 atomic_dec(&fs_info->async_submit_draining);
1465 }
1466
1467 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1468 btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
1469 }
1470
1471 ret = defrag_count;
1472
1473out_ra:
1474 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1475 inode_lock(inode);
1476 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1477 inode_unlock(inode);
1478 }
1479 if (!file)
1480 kfree(ra);
1481 kfree(pages);
1482 return ret;
1483}
1484
1485static noinline int btrfs_ioctl_resize(struct file *file,
1486 void __user *arg)
1487{
1488 struct inode *inode = file_inode(file);
1489 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1490 u64 new_size;
1491 u64 old_size;
1492 u64 devid = 1;
1493 struct btrfs_root *root = BTRFS_I(inode)->root;
1494 struct btrfs_ioctl_vol_args *vol_args;
1495 struct btrfs_trans_handle *trans;
1496 struct btrfs_device *device = NULL;
1497 char *sizestr;
1498 char *retptr;
1499 char *devstr = NULL;
1500 int ret = 0;
1501 int mod = 0;
1502
1503 if (!capable(CAP_SYS_ADMIN))
1504 return -EPERM;
1505
1506 ret = mnt_want_write_file(file);
1507 if (ret)
1508 return ret;
1509
1510 if (atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
1511 mnt_drop_write_file(file);
1512 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1513 }
1514
1515 mutex_lock(&fs_info->volume_mutex);
1516 vol_args = memdup_user(arg, sizeof(*vol_args));
1517 if (IS_ERR(vol_args)) {
1518 ret = PTR_ERR(vol_args);
1519 goto out;
1520 }
1521
1522 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1523
1524 sizestr = vol_args->name;
1525 devstr = strchr(sizestr, ':');
1526 if (devstr) {
1527 sizestr = devstr + 1;
1528 *devstr = '\0';
1529 devstr = vol_args->name;
1530 ret = kstrtoull(devstr, 10, &devid);
1531 if (ret)
1532 goto out_free;
1533 if (!devid) {
1534 ret = -EINVAL;
1535 goto out_free;
1536 }
1537 btrfs_info(fs_info, "resizing devid %llu", devid);
1538 }
1539
1540 device = btrfs_find_device(fs_info, devid, NULL, NULL);
1541 if (!device) {
1542 btrfs_info(fs_info, "resizer unable to find device %llu",
1543 devid);
1544 ret = -ENODEV;
1545 goto out_free;
1546 }
1547
1548 if (!device->writeable) {
1549 btrfs_info(fs_info,
1550 "resizer unable to apply on readonly device %llu",
1551 devid);
1552 ret = -EPERM;
1553 goto out_free;
1554 }
1555
1556 if (!strcmp(sizestr, "max"))
1557 new_size = device->bdev->bd_inode->i_size;
1558 else {
1559 if (sizestr[0] == '-') {
1560 mod = -1;
1561 sizestr++;
1562 } else if (sizestr[0] == '+') {
1563 mod = 1;
1564 sizestr++;
1565 }
1566 new_size = memparse(sizestr, &retptr);
1567 if (*retptr != '\0' || new_size == 0) {
1568 ret = -EINVAL;
1569 goto out_free;
1570 }
1571 }
1572
1573 if (device->is_tgtdev_for_dev_replace) {
1574 ret = -EPERM;
1575 goto out_free;
1576 }
1577
1578 old_size = btrfs_device_get_total_bytes(device);
1579
1580 if (mod < 0) {
1581 if (new_size > old_size) {
1582 ret = -EINVAL;
1583 goto out_free;
1584 }
1585 new_size = old_size - new_size;
1586 } else if (mod > 0) {
1587 if (new_size > ULLONG_MAX - old_size) {
1588 ret = -ERANGE;
1589 goto out_free;
1590 }
1591 new_size = old_size + new_size;
1592 }
1593
1594 if (new_size < SZ_256M) {
1595 ret = -EINVAL;
1596 goto out_free;
1597 }
1598 if (new_size > device->bdev->bd_inode->i_size) {
1599 ret = -EFBIG;
1600 goto out_free;
1601 }
1602
1603 new_size = div_u64(new_size, fs_info->sectorsize);
1604 new_size *= fs_info->sectorsize;
1605
1606 btrfs_info_in_rcu(fs_info, "new size for %s is %llu",
1607 rcu_str_deref(device->name), new_size);
1608
1609 if (new_size > old_size) {
1610 trans = btrfs_start_transaction(root, 0);
1611 if (IS_ERR(trans)) {
1612 ret = PTR_ERR(trans);
1613 goto out_free;
1614 }
1615 ret = btrfs_grow_device(trans, device, new_size);
1616 btrfs_commit_transaction(trans);
1617 } else if (new_size < old_size) {
1618 ret = btrfs_shrink_device(device, new_size);
1619 } /* equal, nothing need to do */
1620
1621out_free:
1622 kfree(vol_args);
1623out:
1624 mutex_unlock(&fs_info->volume_mutex);
1625 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
1626 mnt_drop_write_file(file);
1627 return ret;
1628}
1629
1630static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1631 char *name, unsigned long fd, int subvol,
1632 u64 *transid, bool readonly,
1633 struct btrfs_qgroup_inherit *inherit)
1634{
1635 int namelen;
1636 int ret = 0;
1637
1638 if (!S_ISDIR(file_inode(file)->i_mode))
1639 return -ENOTDIR;
1640
1641 ret = mnt_want_write_file(file);
1642 if (ret)
1643 goto out;
1644
1645 namelen = strlen(name);
1646 if (strchr(name, '/')) {
1647 ret = -EINVAL;
1648 goto out_drop_write;
1649 }
1650
1651 if (name[0] == '.' &&
1652 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1653 ret = -EEXIST;
1654 goto out_drop_write;
1655 }
1656
1657 if (subvol) {
1658 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1659 NULL, transid, readonly, inherit);
1660 } else {
1661 struct fd src = fdget(fd);
1662 struct inode *src_inode;
1663 if (!src.file) {
1664 ret = -EINVAL;
1665 goto out_drop_write;
1666 }
1667
1668 src_inode = file_inode(src.file);
1669 if (src_inode->i_sb != file_inode(file)->i_sb) {
1670 btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
1671 "Snapshot src from another FS");
1672 ret = -EXDEV;
1673 } else if (!inode_owner_or_capable(src_inode)) {
1674 /*
1675 * Subvolume creation is not restricted, but snapshots
1676 * are limited to own subvolumes only
1677 */
1678 ret = -EPERM;
1679 } else {
1680 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1681 BTRFS_I(src_inode)->root,
1682 transid, readonly, inherit);
1683 }
1684 fdput(src);
1685 }
1686out_drop_write:
1687 mnt_drop_write_file(file);
1688out:
1689 return ret;
1690}
1691
1692static noinline int btrfs_ioctl_snap_create(struct file *file,
1693 void __user *arg, int subvol)
1694{
1695 struct btrfs_ioctl_vol_args *vol_args;
1696 int ret;
1697
1698 if (!S_ISDIR(file_inode(file)->i_mode))
1699 return -ENOTDIR;
1700
1701 vol_args = memdup_user(arg, sizeof(*vol_args));
1702 if (IS_ERR(vol_args))
1703 return PTR_ERR(vol_args);
1704 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1705
1706 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1707 vol_args->fd, subvol,
1708 NULL, false, NULL);
1709
1710 kfree(vol_args);
1711 return ret;
1712}
1713
1714static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1715 void __user *arg, int subvol)
1716{
1717 struct btrfs_ioctl_vol_args_v2 *vol_args;
1718 int ret;
1719 u64 transid = 0;
1720 u64 *ptr = NULL;
1721 bool readonly = false;
1722 struct btrfs_qgroup_inherit *inherit = NULL;
1723
1724 if (!S_ISDIR(file_inode(file)->i_mode))
1725 return -ENOTDIR;
1726
1727 vol_args = memdup_user(arg, sizeof(*vol_args));
1728 if (IS_ERR(vol_args))
1729 return PTR_ERR(vol_args);
1730 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1731
1732 if (vol_args->flags &
1733 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1734 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1735 ret = -EOPNOTSUPP;
1736 goto free_args;
1737 }
1738
1739 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1740 ptr = &transid;
1741 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1742 readonly = true;
1743 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1744 if (vol_args->size > PAGE_SIZE) {
1745 ret = -EINVAL;
1746 goto free_args;
1747 }
1748 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1749 if (IS_ERR(inherit)) {
1750 ret = PTR_ERR(inherit);
1751 goto free_args;
1752 }
1753 }
1754
1755 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1756 vol_args->fd, subvol, ptr,
1757 readonly, inherit);
1758 if (ret)
1759 goto free_inherit;
1760
1761 if (ptr && copy_to_user(arg +
1762 offsetof(struct btrfs_ioctl_vol_args_v2,
1763 transid),
1764 ptr, sizeof(*ptr)))
1765 ret = -EFAULT;
1766
1767free_inherit:
1768 kfree(inherit);
1769free_args:
1770 kfree(vol_args);
1771 return ret;
1772}
1773
1774static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1775 void __user *arg)
1776{
1777 struct inode *inode = file_inode(file);
1778 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1779 struct btrfs_root *root = BTRFS_I(inode)->root;
1780 int ret = 0;
1781 u64 flags = 0;
1782
1783 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1784 return -EINVAL;
1785
1786 down_read(&fs_info->subvol_sem);
1787 if (btrfs_root_readonly(root))
1788 flags |= BTRFS_SUBVOL_RDONLY;
1789 up_read(&fs_info->subvol_sem);
1790
1791 if (copy_to_user(arg, &flags, sizeof(flags)))
1792 ret = -EFAULT;
1793
1794 return ret;
1795}
1796
1797static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1798 void __user *arg)
1799{
1800 struct inode *inode = file_inode(file);
1801 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1802 struct btrfs_root *root = BTRFS_I(inode)->root;
1803 struct btrfs_trans_handle *trans;
1804 u64 root_flags;
1805 u64 flags;
1806 int ret = 0;
1807
1808 if (!inode_owner_or_capable(inode))
1809 return -EPERM;
1810
1811 ret = mnt_want_write_file(file);
1812 if (ret)
1813 goto out;
1814
1815 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1816 ret = -EINVAL;
1817 goto out_drop_write;
1818 }
1819
1820 if (copy_from_user(&flags, arg, sizeof(flags))) {
1821 ret = -EFAULT;
1822 goto out_drop_write;
1823 }
1824
1825 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1826 ret = -EINVAL;
1827 goto out_drop_write;
1828 }
1829
1830 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1831 ret = -EOPNOTSUPP;
1832 goto out_drop_write;
1833 }
1834
1835 down_write(&fs_info->subvol_sem);
1836
1837 /* nothing to do */
1838 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1839 goto out_drop_sem;
1840
1841 root_flags = btrfs_root_flags(&root->root_item);
1842 if (flags & BTRFS_SUBVOL_RDONLY) {
1843 btrfs_set_root_flags(&root->root_item,
1844 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1845 } else {
1846 /*
1847 * Block RO -> RW transition if this subvolume is involved in
1848 * send
1849 */
1850 spin_lock(&root->root_item_lock);
1851 if (root->send_in_progress == 0) {
1852 btrfs_set_root_flags(&root->root_item,
1853 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1854 spin_unlock(&root->root_item_lock);
1855 } else {
1856 spin_unlock(&root->root_item_lock);
1857 btrfs_warn(fs_info,
1858 "Attempt to set subvolume %llu read-write during send",
1859 root->root_key.objectid);
1860 ret = -EPERM;
1861 goto out_drop_sem;
1862 }
1863 }
1864
1865 trans = btrfs_start_transaction(root, 1);
1866 if (IS_ERR(trans)) {
1867 ret = PTR_ERR(trans);
1868 goto out_reset;
1869 }
1870
1871 ret = btrfs_update_root(trans, fs_info->tree_root,
1872 &root->root_key, &root->root_item);
1873
1874 btrfs_commit_transaction(trans);
1875out_reset:
1876 if (ret)
1877 btrfs_set_root_flags(&root->root_item, root_flags);
1878out_drop_sem:
1879 up_write(&fs_info->subvol_sem);
1880out_drop_write:
1881 mnt_drop_write_file(file);
1882out:
1883 return ret;
1884}
1885
1886/*
1887 * helper to check if the subvolume references other subvolumes
1888 */
1889static noinline int may_destroy_subvol(struct btrfs_root *root)
1890{
1891 struct btrfs_fs_info *fs_info = root->fs_info;
1892 struct btrfs_path *path;
1893 struct btrfs_dir_item *di;
1894 struct btrfs_key key;
1895 u64 dir_id;
1896 int ret;
1897
1898 path = btrfs_alloc_path();
1899 if (!path)
1900 return -ENOMEM;
1901
1902 /* Make sure this root isn't set as the default subvol */
1903 dir_id = btrfs_super_root_dir(fs_info->super_copy);
1904 di = btrfs_lookup_dir_item(NULL, fs_info->tree_root, path,
1905 dir_id, "default", 7, 0);
1906 if (di && !IS_ERR(di)) {
1907 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1908 if (key.objectid == root->root_key.objectid) {
1909 ret = -EPERM;
1910 btrfs_err(fs_info,
1911 "deleting default subvolume %llu is not allowed",
1912 key.objectid);
1913 goto out;
1914 }
1915 btrfs_release_path(path);
1916 }
1917
1918 key.objectid = root->root_key.objectid;
1919 key.type = BTRFS_ROOT_REF_KEY;
1920 key.offset = (u64)-1;
1921
1922 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
1923 if (ret < 0)
1924 goto out;
1925 BUG_ON(ret == 0);
1926
1927 ret = 0;
1928 if (path->slots[0] > 0) {
1929 path->slots[0]--;
1930 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1931 if (key.objectid == root->root_key.objectid &&
1932 key.type == BTRFS_ROOT_REF_KEY)
1933 ret = -ENOTEMPTY;
1934 }
1935out:
1936 btrfs_free_path(path);
1937 return ret;
1938}
1939
1940static noinline int key_in_sk(struct btrfs_key *key,
1941 struct btrfs_ioctl_search_key *sk)
1942{
1943 struct btrfs_key test;
1944 int ret;
1945
1946 test.objectid = sk->min_objectid;
1947 test.type = sk->min_type;
1948 test.offset = sk->min_offset;
1949
1950 ret = btrfs_comp_cpu_keys(key, &test);
1951 if (ret < 0)
1952 return 0;
1953
1954 test.objectid = sk->max_objectid;
1955 test.type = sk->max_type;
1956 test.offset = sk->max_offset;
1957
1958 ret = btrfs_comp_cpu_keys(key, &test);
1959 if (ret > 0)
1960 return 0;
1961 return 1;
1962}
1963
1964static noinline int copy_to_sk(struct btrfs_path *path,
1965 struct btrfs_key *key,
1966 struct btrfs_ioctl_search_key *sk,
1967 size_t *buf_size,
1968 char __user *ubuf,
1969 unsigned long *sk_offset,
1970 int *num_found)
1971{
1972 u64 found_transid;
1973 struct extent_buffer *leaf;
1974 struct btrfs_ioctl_search_header sh;
1975 struct btrfs_key test;
1976 unsigned long item_off;
1977 unsigned long item_len;
1978 int nritems;
1979 int i;
1980 int slot;
1981 int ret = 0;
1982
1983 leaf = path->nodes[0];
1984 slot = path->slots[0];
1985 nritems = btrfs_header_nritems(leaf);
1986
1987 if (btrfs_header_generation(leaf) > sk->max_transid) {
1988 i = nritems;
1989 goto advance_key;
1990 }
1991 found_transid = btrfs_header_generation(leaf);
1992
1993 for (i = slot; i < nritems; i++) {
1994 item_off = btrfs_item_ptr_offset(leaf, i);
1995 item_len = btrfs_item_size_nr(leaf, i);
1996
1997 btrfs_item_key_to_cpu(leaf, key, i);
1998 if (!key_in_sk(key, sk))
1999 continue;
2000
2001 if (sizeof(sh) + item_len > *buf_size) {
2002 if (*num_found) {
2003 ret = 1;
2004 goto out;
2005 }
2006
2007 /*
2008 * return one empty item back for v1, which does not
2009 * handle -EOVERFLOW
2010 */
2011
2012 *buf_size = sizeof(sh) + item_len;
2013 item_len = 0;
2014 ret = -EOVERFLOW;
2015 }
2016
2017 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2018 ret = 1;
2019 goto out;
2020 }
2021
2022 sh.objectid = key->objectid;
2023 sh.offset = key->offset;
2024 sh.type = key->type;
2025 sh.len = item_len;
2026 sh.transid = found_transid;
2027
2028 /* copy search result header */
2029 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
2030 ret = -EFAULT;
2031 goto out;
2032 }
2033
2034 *sk_offset += sizeof(sh);
2035
2036 if (item_len) {
2037 char __user *up = ubuf + *sk_offset;
2038 /* copy the item */
2039 if (read_extent_buffer_to_user(leaf, up,
2040 item_off, item_len)) {
2041 ret = -EFAULT;
2042 goto out;
2043 }
2044
2045 *sk_offset += item_len;
2046 }
2047 (*num_found)++;
2048
2049 if (ret) /* -EOVERFLOW from above */
2050 goto out;
2051
2052 if (*num_found >= sk->nr_items) {
2053 ret = 1;
2054 goto out;
2055 }
2056 }
2057advance_key:
2058 ret = 0;
2059 test.objectid = sk->max_objectid;
2060 test.type = sk->max_type;
2061 test.offset = sk->max_offset;
2062 if (btrfs_comp_cpu_keys(key, &test) >= 0)
2063 ret = 1;
2064 else if (key->offset < (u64)-1)
2065 key->offset++;
2066 else if (key->type < (u8)-1) {
2067 key->offset = 0;
2068 key->type++;
2069 } else if (key->objectid < (u64)-1) {
2070 key->offset = 0;
2071 key->type = 0;
2072 key->objectid++;
2073 } else
2074 ret = 1;
2075out:
2076 /*
2077 * 0: all items from this leaf copied, continue with next
2078 * 1: * more items can be copied, but unused buffer is too small
2079 * * all items were found
2080 * Either way, it will stops the loop which iterates to the next
2081 * leaf
2082 * -EOVERFLOW: item was to large for buffer
2083 * -EFAULT: could not copy extent buffer back to userspace
2084 */
2085 return ret;
2086}
2087
2088static noinline int search_ioctl(struct inode *inode,
2089 struct btrfs_ioctl_search_key *sk,
2090 size_t *buf_size,
2091 char __user *ubuf)
2092{
2093 struct btrfs_fs_info *info = btrfs_sb(inode->i_sb);
2094 struct btrfs_root *root;
2095 struct btrfs_key key;
2096 struct btrfs_path *path;
2097 int ret;
2098 int num_found = 0;
2099 unsigned long sk_offset = 0;
2100
2101 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2102 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2103 return -EOVERFLOW;
2104 }
2105
2106 path = btrfs_alloc_path();
2107 if (!path)
2108 return -ENOMEM;
2109
2110 if (sk->tree_id == 0) {
2111 /* search the root of the inode that was passed */
2112 root = BTRFS_I(inode)->root;
2113 } else {
2114 key.objectid = sk->tree_id;
2115 key.type = BTRFS_ROOT_ITEM_KEY;
2116 key.offset = (u64)-1;
2117 root = btrfs_read_fs_root_no_name(info, &key);
2118 if (IS_ERR(root)) {
2119 btrfs_free_path(path);
2120 return -ENOENT;
2121 }
2122 }
2123
2124 key.objectid = sk->min_objectid;
2125 key.type = sk->min_type;
2126 key.offset = sk->min_offset;
2127
2128 while (1) {
2129 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2130 if (ret != 0) {
2131 if (ret > 0)
2132 ret = 0;
2133 goto err;
2134 }
2135 ret = copy_to_sk(path, &key, sk, buf_size, ubuf,
2136 &sk_offset, &num_found);
2137 btrfs_release_path(path);
2138 if (ret)
2139 break;
2140
2141 }
2142 if (ret > 0)
2143 ret = 0;
2144err:
2145 sk->nr_items = num_found;
2146 btrfs_free_path(path);
2147 return ret;
2148}
2149
2150static noinline int btrfs_ioctl_tree_search(struct file *file,
2151 void __user *argp)
2152{
2153 struct btrfs_ioctl_search_args __user *uargs;
2154 struct btrfs_ioctl_search_key sk;
2155 struct inode *inode;
2156 int ret;
2157 size_t buf_size;
2158
2159 if (!capable(CAP_SYS_ADMIN))
2160 return -EPERM;
2161
2162 uargs = (struct btrfs_ioctl_search_args __user *)argp;
2163
2164 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2165 return -EFAULT;
2166
2167 buf_size = sizeof(uargs->buf);
2168
2169 inode = file_inode(file);
2170 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2171
2172 /*
2173 * In the origin implementation an overflow is handled by returning a
2174 * search header with a len of zero, so reset ret.
2175 */
2176 if (ret == -EOVERFLOW)
2177 ret = 0;
2178
2179 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2180 ret = -EFAULT;
2181 return ret;
2182}
2183
2184static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2185 void __user *argp)
2186{
2187 struct btrfs_ioctl_search_args_v2 __user *uarg;
2188 struct btrfs_ioctl_search_args_v2 args;
2189 struct inode *inode;
2190 int ret;
2191 size_t buf_size;
2192 const size_t buf_limit = SZ_16M;
2193
2194 if (!capable(CAP_SYS_ADMIN))
2195 return -EPERM;
2196
2197 /* copy search header and buffer size */
2198 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2199 if (copy_from_user(&args, uarg, sizeof(args)))
2200 return -EFAULT;
2201
2202 buf_size = args.buf_size;
2203
2204 if (buf_size < sizeof(struct btrfs_ioctl_search_header))
2205 return -EOVERFLOW;
2206
2207 /* limit result size to 16MB */
2208 if (buf_size > buf_limit)
2209 buf_size = buf_limit;
2210
2211 inode = file_inode(file);
2212 ret = search_ioctl(inode, &args.key, &buf_size,
2213 (char *)(&uarg->buf[0]));
2214 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2215 ret = -EFAULT;
2216 else if (ret == -EOVERFLOW &&
2217 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2218 ret = -EFAULT;
2219
2220 return ret;
2221}
2222
2223/*
2224 * Search INODE_REFs to identify path name of 'dirid' directory
2225 * in a 'tree_id' tree. and sets path name to 'name'.
2226 */
2227static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2228 u64 tree_id, u64 dirid, char *name)
2229{
2230 struct btrfs_root *root;
2231 struct btrfs_key key;
2232 char *ptr;
2233 int ret = -1;
2234 int slot;
2235 int len;
2236 int total_len = 0;
2237 struct btrfs_inode_ref *iref;
2238 struct extent_buffer *l;
2239 struct btrfs_path *path;
2240
2241 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2242 name[0]='\0';
2243 return 0;
2244 }
2245
2246 path = btrfs_alloc_path();
2247 if (!path)
2248 return -ENOMEM;
2249
2250 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2251
2252 key.objectid = tree_id;
2253 key.type = BTRFS_ROOT_ITEM_KEY;
2254 key.offset = (u64)-1;
2255 root = btrfs_read_fs_root_no_name(info, &key);
2256 if (IS_ERR(root)) {
2257 btrfs_err(info, "could not find root %llu", tree_id);
2258 ret = -ENOENT;
2259 goto out;
2260 }
2261
2262 key.objectid = dirid;
2263 key.type = BTRFS_INODE_REF_KEY;
2264 key.offset = (u64)-1;
2265
2266 while (1) {
2267 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2268 if (ret < 0)
2269 goto out;
2270 else if (ret > 0) {
2271 ret = btrfs_previous_item(root, path, dirid,
2272 BTRFS_INODE_REF_KEY);
2273 if (ret < 0)
2274 goto out;
2275 else if (ret > 0) {
2276 ret = -ENOENT;
2277 goto out;
2278 }
2279 }
2280
2281 l = path->nodes[0];
2282 slot = path->slots[0];
2283 btrfs_item_key_to_cpu(l, &key, slot);
2284
2285 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2286 len = btrfs_inode_ref_name_len(l, iref);
2287 ptr -= len + 1;
2288 total_len += len + 1;
2289 if (ptr < name) {
2290 ret = -ENAMETOOLONG;
2291 goto out;
2292 }
2293
2294 *(ptr + len) = '/';
2295 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2296
2297 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2298 break;
2299
2300 btrfs_release_path(path);
2301 key.objectid = key.offset;
2302 key.offset = (u64)-1;
2303 dirid = key.objectid;
2304 }
2305 memmove(name, ptr, total_len);
2306 name[total_len] = '\0';
2307 ret = 0;
2308out:
2309 btrfs_free_path(path);
2310 return ret;
2311}
2312
2313static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2314 void __user *argp)
2315{
2316 struct btrfs_ioctl_ino_lookup_args *args;
2317 struct inode *inode;
2318 int ret = 0;
2319
2320 args = memdup_user(argp, sizeof(*args));
2321 if (IS_ERR(args))
2322 return PTR_ERR(args);
2323
2324 inode = file_inode(file);
2325
2326 /*
2327 * Unprivileged query to obtain the containing subvolume root id. The
2328 * path is reset so it's consistent with btrfs_search_path_in_tree.
2329 */
2330 if (args->treeid == 0)
2331 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2332
2333 if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2334 args->name[0] = 0;
2335 goto out;
2336 }
2337
2338 if (!capable(CAP_SYS_ADMIN)) {
2339 ret = -EPERM;
2340 goto out;
2341 }
2342
2343 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2344 args->treeid, args->objectid,
2345 args->name);
2346
2347out:
2348 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2349 ret = -EFAULT;
2350
2351 kfree(args);
2352 return ret;
2353}
2354
2355static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2356 void __user *arg)
2357{
2358 struct dentry *parent = file->f_path.dentry;
2359 struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb);
2360 struct dentry *dentry;
2361 struct inode *dir = d_inode(parent);
2362 struct inode *inode;
2363 struct btrfs_root *root = BTRFS_I(dir)->root;
2364 struct btrfs_root *dest = NULL;
2365 struct btrfs_ioctl_vol_args *vol_args;
2366 struct btrfs_trans_handle *trans;
2367 struct btrfs_block_rsv block_rsv;
2368 u64 root_flags;
2369 u64 qgroup_reserved;
2370 int namelen;
2371 int ret;
2372 int err = 0;
2373
2374 if (!S_ISDIR(dir->i_mode))
2375 return -ENOTDIR;
2376
2377 vol_args = memdup_user(arg, sizeof(*vol_args));
2378 if (IS_ERR(vol_args))
2379 return PTR_ERR(vol_args);
2380
2381 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2382 namelen = strlen(vol_args->name);
2383 if (strchr(vol_args->name, '/') ||
2384 strncmp(vol_args->name, "..", namelen) == 0) {
2385 err = -EINVAL;
2386 goto out;
2387 }
2388
2389 err = mnt_want_write_file(file);
2390 if (err)
2391 goto out;
2392
2393
2394 err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
2395 if (err == -EINTR)
2396 goto out_drop_write;
2397 dentry = lookup_one_len(vol_args->name, parent, namelen);
2398 if (IS_ERR(dentry)) {
2399 err = PTR_ERR(dentry);
2400 goto out_unlock_dir;
2401 }
2402
2403 if (d_really_is_negative(dentry)) {
2404 err = -ENOENT;
2405 goto out_dput;
2406 }
2407
2408 inode = d_inode(dentry);
2409 dest = BTRFS_I(inode)->root;
2410 if (!capable(CAP_SYS_ADMIN)) {
2411 /*
2412 * Regular user. Only allow this with a special mount
2413 * option, when the user has write+exec access to the
2414 * subvol root, and when rmdir(2) would have been
2415 * allowed.
2416 *
2417 * Note that this is _not_ check that the subvol is
2418 * empty or doesn't contain data that we wouldn't
2419 * otherwise be able to delete.
2420 *
2421 * Users who want to delete empty subvols should try
2422 * rmdir(2).
2423 */
2424 err = -EPERM;
2425 if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))
2426 goto out_dput;
2427
2428 /*
2429 * Do not allow deletion if the parent dir is the same
2430 * as the dir to be deleted. That means the ioctl
2431 * must be called on the dentry referencing the root
2432 * of the subvol, not a random directory contained
2433 * within it.
2434 */
2435 err = -EINVAL;
2436 if (root == dest)
2437 goto out_dput;
2438
2439 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2440 if (err)
2441 goto out_dput;
2442 }
2443
2444 /* check if subvolume may be deleted by a user */
2445 err = btrfs_may_delete(dir, dentry, 1);
2446 if (err)
2447 goto out_dput;
2448
2449 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2450 err = -EINVAL;
2451 goto out_dput;
2452 }
2453
2454 inode_lock(inode);
2455
2456 /*
2457 * Don't allow to delete a subvolume with send in progress. This is
2458 * inside the i_mutex so the error handling that has to drop the bit
2459 * again is not run concurrently.
2460 */
2461 spin_lock(&dest->root_item_lock);
2462 root_flags = btrfs_root_flags(&dest->root_item);
2463 if (dest->send_in_progress == 0) {
2464 btrfs_set_root_flags(&dest->root_item,
2465 root_flags | BTRFS_ROOT_SUBVOL_DEAD);
2466 spin_unlock(&dest->root_item_lock);
2467 } else {
2468 spin_unlock(&dest->root_item_lock);
2469 btrfs_warn(fs_info,
2470 "Attempt to delete subvolume %llu during send",
2471 dest->root_key.objectid);
2472 err = -EPERM;
2473 goto out_unlock_inode;
2474 }
2475
2476 down_write(&fs_info->subvol_sem);
2477
2478 err = may_destroy_subvol(dest);
2479 if (err)
2480 goto out_up_write;
2481
2482 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2483 /*
2484 * One for dir inode, two for dir entries, two for root
2485 * ref/backref.
2486 */
2487 err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2488 5, &qgroup_reserved, true);
2489 if (err)
2490 goto out_up_write;
2491
2492 trans = btrfs_start_transaction(root, 0);
2493 if (IS_ERR(trans)) {
2494 err = PTR_ERR(trans);
2495 goto out_release;
2496 }
2497 trans->block_rsv = &block_rsv;
2498 trans->bytes_reserved = block_rsv.size;
2499
2500 btrfs_record_snapshot_destroy(trans, dir);
2501
2502 ret = btrfs_unlink_subvol(trans, root, dir,
2503 dest->root_key.objectid,
2504 dentry->d_name.name,
2505 dentry->d_name.len);
2506 if (ret) {
2507 err = ret;
2508 btrfs_abort_transaction(trans, ret);
2509 goto out_end_trans;
2510 }
2511
2512 btrfs_record_root_in_trans(trans, dest);
2513
2514 memset(&dest->root_item.drop_progress, 0,
2515 sizeof(dest->root_item.drop_progress));
2516 dest->root_item.drop_level = 0;
2517 btrfs_set_root_refs(&dest->root_item, 0);
2518
2519 if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
2520 ret = btrfs_insert_orphan_item(trans,
2521 fs_info->tree_root,
2522 dest->root_key.objectid);
2523 if (ret) {
2524 btrfs_abort_transaction(trans, ret);
2525 err = ret;
2526 goto out_end_trans;
2527 }
2528 }
2529
2530 ret = btrfs_uuid_tree_rem(trans, fs_info, dest->root_item.uuid,
2531 BTRFS_UUID_KEY_SUBVOL,
2532 dest->root_key.objectid);
2533 if (ret && ret != -ENOENT) {
2534 btrfs_abort_transaction(trans, ret);
2535 err = ret;
2536 goto out_end_trans;
2537 }
2538 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
2539 ret = btrfs_uuid_tree_rem(trans, fs_info,
2540 dest->root_item.received_uuid,
2541 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
2542 dest->root_key.objectid);
2543 if (ret && ret != -ENOENT) {
2544 btrfs_abort_transaction(trans, ret);
2545 err = ret;
2546 goto out_end_trans;
2547 }
2548 }
2549
2550out_end_trans:
2551 trans->block_rsv = NULL;
2552 trans->bytes_reserved = 0;
2553 ret = btrfs_end_transaction(trans);
2554 if (ret && !err)
2555 err = ret;
2556 inode->i_flags |= S_DEAD;
2557out_release:
2558 btrfs_subvolume_release_metadata(fs_info, &block_rsv, qgroup_reserved);
2559out_up_write:
2560 up_write(&fs_info->subvol_sem);
2561 if (err) {
2562 spin_lock(&dest->root_item_lock);
2563 root_flags = btrfs_root_flags(&dest->root_item);
2564 btrfs_set_root_flags(&dest->root_item,
2565 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
2566 spin_unlock(&dest->root_item_lock);
2567 }
2568out_unlock_inode:
2569 inode_unlock(inode);
2570 if (!err) {
2571 d_invalidate(dentry);
2572 btrfs_invalidate_inodes(dest);
2573 d_delete(dentry);
2574 ASSERT(dest->send_in_progress == 0);
2575
2576 /* the last ref */
2577 if (dest->ino_cache_inode) {
2578 iput(dest->ino_cache_inode);
2579 dest->ino_cache_inode = NULL;
2580 }
2581 }
2582out_dput:
2583 dput(dentry);
2584out_unlock_dir:
2585 inode_unlock(dir);
2586out_drop_write:
2587 mnt_drop_write_file(file);
2588out:
2589 kfree(vol_args);
2590 return err;
2591}
2592
2593static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2594{
2595 struct inode *inode = file_inode(file);
2596 struct btrfs_root *root = BTRFS_I(inode)->root;
2597 struct btrfs_ioctl_defrag_range_args *range;
2598 int ret;
2599
2600 ret = mnt_want_write_file(file);
2601 if (ret)
2602 return ret;
2603
2604 if (btrfs_root_readonly(root)) {
2605 ret = -EROFS;
2606 goto out;
2607 }
2608
2609 switch (inode->i_mode & S_IFMT) {
2610 case S_IFDIR:
2611 if (!capable(CAP_SYS_ADMIN)) {
2612 ret = -EPERM;
2613 goto out;
2614 }
2615 ret = btrfs_defrag_root(root);
2616 if (ret)
2617 goto out;
2618 ret = btrfs_defrag_root(root->fs_info->extent_root);
2619 break;
2620 case S_IFREG:
2621 if (!(file->f_mode & FMODE_WRITE)) {
2622 ret = -EINVAL;
2623 goto out;
2624 }
2625
2626 range = kzalloc(sizeof(*range), GFP_KERNEL);
2627 if (!range) {
2628 ret = -ENOMEM;
2629 goto out;
2630 }
2631
2632 if (argp) {
2633 if (copy_from_user(range, argp,
2634 sizeof(*range))) {
2635 ret = -EFAULT;
2636 kfree(range);
2637 goto out;
2638 }
2639 /* compression requires us to start the IO */
2640 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2641 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2642 range->extent_thresh = (u32)-1;
2643 }
2644 } else {
2645 /* the rest are all set to zero by kzalloc */
2646 range->len = (u64)-1;
2647 }
2648 ret = btrfs_defrag_file(file_inode(file), file,
2649 range, 0, 0);
2650 if (ret > 0)
2651 ret = 0;
2652 kfree(range);
2653 break;
2654 default:
2655 ret = -EINVAL;
2656 }
2657out:
2658 mnt_drop_write_file(file);
2659 return ret;
2660}
2661
2662static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg)
2663{
2664 struct btrfs_ioctl_vol_args *vol_args;
2665 int ret;
2666
2667 if (!capable(CAP_SYS_ADMIN))
2668 return -EPERM;
2669
2670 if (atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1))
2671 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2672
2673 mutex_lock(&fs_info->volume_mutex);
2674 vol_args = memdup_user(arg, sizeof(*vol_args));
2675 if (IS_ERR(vol_args)) {
2676 ret = PTR_ERR(vol_args);
2677 goto out;
2678 }
2679
2680 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2681 ret = btrfs_init_new_device(fs_info, vol_args->name);
2682
2683 if (!ret)
2684 btrfs_info(fs_info, "disk added %s", vol_args->name);
2685
2686 kfree(vol_args);
2687out:
2688 mutex_unlock(&fs_info->volume_mutex);
2689 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
2690 return ret;
2691}
2692
2693static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
2694{
2695 struct inode *inode = file_inode(file);
2696 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2697 struct btrfs_ioctl_vol_args_v2 *vol_args;
2698 int ret;
2699
2700 if (!capable(CAP_SYS_ADMIN))
2701 return -EPERM;
2702
2703 ret = mnt_want_write_file(file);
2704 if (ret)
2705 return ret;
2706
2707 vol_args = memdup_user(arg, sizeof(*vol_args));
2708 if (IS_ERR(vol_args)) {
2709 ret = PTR_ERR(vol_args);
2710 goto err_drop;
2711 }
2712
2713 /* Check for compatibility reject unknown flags */
2714 if (vol_args->flags & ~BTRFS_VOL_ARG_V2_FLAGS_SUPPORTED)
2715 return -EOPNOTSUPP;
2716
2717 if (atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
2718 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2719 goto out;
2720 }
2721
2722 mutex_lock(&fs_info->volume_mutex);
2723 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
2724 ret = btrfs_rm_device(fs_info, NULL, vol_args->devid);
2725 } else {
2726 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
2727 ret = btrfs_rm_device(fs_info, vol_args->name, 0);
2728 }
2729 mutex_unlock(&fs_info->volume_mutex);
2730 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
2731
2732 if (!ret) {
2733 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
2734 btrfs_info(fs_info, "device deleted: id %llu",
2735 vol_args->devid);
2736 else
2737 btrfs_info(fs_info, "device deleted: %s",
2738 vol_args->name);
2739 }
2740out:
2741 kfree(vol_args);
2742err_drop:
2743 mnt_drop_write_file(file);
2744 return ret;
2745}
2746
2747static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2748{
2749 struct inode *inode = file_inode(file);
2750 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2751 struct btrfs_ioctl_vol_args *vol_args;
2752 int ret;
2753
2754 if (!capable(CAP_SYS_ADMIN))
2755 return -EPERM;
2756
2757 ret = mnt_want_write_file(file);
2758 if (ret)
2759 return ret;
2760
2761 if (atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
2762 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2763 goto out_drop_write;
2764 }
2765
2766 vol_args = memdup_user(arg, sizeof(*vol_args));
2767 if (IS_ERR(vol_args)) {
2768 ret = PTR_ERR(vol_args);
2769 goto out;
2770 }
2771
2772 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2773 mutex_lock(&fs_info->volume_mutex);
2774 ret = btrfs_rm_device(fs_info, vol_args->name, 0);
2775 mutex_unlock(&fs_info->volume_mutex);
2776
2777 if (!ret)
2778 btrfs_info(fs_info, "disk deleted %s", vol_args->name);
2779 kfree(vol_args);
2780out:
2781 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
2782out_drop_write:
2783 mnt_drop_write_file(file);
2784
2785 return ret;
2786}
2787
2788static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,
2789 void __user *arg)
2790{
2791 struct btrfs_ioctl_fs_info_args *fi_args;
2792 struct btrfs_device *device;
2793 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2794 int ret = 0;
2795
2796 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2797 if (!fi_args)
2798 return -ENOMEM;
2799
2800 mutex_lock(&fs_devices->device_list_mutex);
2801 fi_args->num_devices = fs_devices->num_devices;
2802 memcpy(&fi_args->fsid, fs_info->fsid, sizeof(fi_args->fsid));
2803
2804 list_for_each_entry(device, &fs_devices->devices, dev_list) {
2805 if (device->devid > fi_args->max_id)
2806 fi_args->max_id = device->devid;
2807 }
2808 mutex_unlock(&fs_devices->device_list_mutex);
2809
2810 fi_args->nodesize = fs_info->super_copy->nodesize;
2811 fi_args->sectorsize = fs_info->super_copy->sectorsize;
2812 fi_args->clone_alignment = fs_info->super_copy->sectorsize;
2813
2814 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2815 ret = -EFAULT;
2816
2817 kfree(fi_args);
2818 return ret;
2819}
2820
2821static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,
2822 void __user *arg)
2823{
2824 struct btrfs_ioctl_dev_info_args *di_args;
2825 struct btrfs_device *dev;
2826 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2827 int ret = 0;
2828 char *s_uuid = NULL;
2829
2830 di_args = memdup_user(arg, sizeof(*di_args));
2831 if (IS_ERR(di_args))
2832 return PTR_ERR(di_args);
2833
2834 if (!btrfs_is_empty_uuid(di_args->uuid))
2835 s_uuid = di_args->uuid;
2836
2837 mutex_lock(&fs_devices->device_list_mutex);
2838 dev = btrfs_find_device(fs_info, di_args->devid, s_uuid, NULL);
2839
2840 if (!dev) {
2841 ret = -ENODEV;
2842 goto out;
2843 }
2844
2845 di_args->devid = dev->devid;
2846 di_args->bytes_used = btrfs_device_get_bytes_used(dev);
2847 di_args->total_bytes = btrfs_device_get_total_bytes(dev);
2848 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2849 if (dev->name) {
2850 struct rcu_string *name;
2851
2852 rcu_read_lock();
2853 name = rcu_dereference(dev->name);
2854 strncpy(di_args->path, name->str, sizeof(di_args->path));
2855 rcu_read_unlock();
2856 di_args->path[sizeof(di_args->path) - 1] = 0;
2857 } else {
2858 di_args->path[0] = '\0';
2859 }
2860
2861out:
2862 mutex_unlock(&fs_devices->device_list_mutex);
2863 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2864 ret = -EFAULT;
2865
2866 kfree(di_args);
2867 return ret;
2868}
2869
2870static struct page *extent_same_get_page(struct inode *inode, pgoff_t index)
2871{
2872 struct page *page;
2873
2874 page = grab_cache_page(inode->i_mapping, index);
2875 if (!page)
2876 return ERR_PTR(-ENOMEM);
2877
2878 if (!PageUptodate(page)) {
2879 int ret;
2880
2881 ret = btrfs_readpage(NULL, page);
2882 if (ret)
2883 return ERR_PTR(ret);
2884 lock_page(page);
2885 if (!PageUptodate(page)) {
2886 unlock_page(page);
2887 put_page(page);
2888 return ERR_PTR(-EIO);
2889 }
2890 if (page->mapping != inode->i_mapping) {
2891 unlock_page(page);
2892 put_page(page);
2893 return ERR_PTR(-EAGAIN);
2894 }
2895 }
2896
2897 return page;
2898}
2899
2900static int gather_extent_pages(struct inode *inode, struct page **pages,
2901 int num_pages, u64 off)
2902{
2903 int i;
2904 pgoff_t index = off >> PAGE_SHIFT;
2905
2906 for (i = 0; i < num_pages; i++) {
2907again:
2908 pages[i] = extent_same_get_page(inode, index + i);
2909 if (IS_ERR(pages[i])) {
2910 int err = PTR_ERR(pages[i]);
2911
2912 if (err == -EAGAIN)
2913 goto again;
2914 pages[i] = NULL;
2915 return err;
2916 }
2917 }
2918 return 0;
2919}
2920
2921static int lock_extent_range(struct inode *inode, u64 off, u64 len,
2922 bool retry_range_locking)
2923{
2924 /*
2925 * Do any pending delalloc/csum calculations on inode, one way or
2926 * another, and lock file content.
2927 * The locking order is:
2928 *
2929 * 1) pages
2930 * 2) range in the inode's io tree
2931 */
2932 while (1) {
2933 struct btrfs_ordered_extent *ordered;
2934 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2935 ordered = btrfs_lookup_first_ordered_extent(inode,
2936 off + len - 1);
2937 if ((!ordered ||
2938 ordered->file_offset + ordered->len <= off ||
2939 ordered->file_offset >= off + len) &&
2940 !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2941 off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
2942 if (ordered)
2943 btrfs_put_ordered_extent(ordered);
2944 break;
2945 }
2946 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2947 if (ordered)
2948 btrfs_put_ordered_extent(ordered);
2949 if (!retry_range_locking)
2950 return -EAGAIN;
2951 btrfs_wait_ordered_range(inode, off, len);
2952 }
2953 return 0;
2954}
2955
2956static void btrfs_double_inode_unlock(struct inode *inode1, struct inode *inode2)
2957{
2958 inode_unlock(inode1);
2959 inode_unlock(inode2);
2960}
2961
2962static void btrfs_double_inode_lock(struct inode *inode1, struct inode *inode2)
2963{
2964 if (inode1 < inode2)
2965 swap(inode1, inode2);
2966
2967 inode_lock_nested(inode1, I_MUTEX_PARENT);
2968 inode_lock_nested(inode2, I_MUTEX_CHILD);
2969}
2970
2971static void btrfs_double_extent_unlock(struct inode *inode1, u64 loff1,
2972 struct inode *inode2, u64 loff2, u64 len)
2973{
2974 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
2975 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
2976}
2977
2978static int btrfs_double_extent_lock(struct inode *inode1, u64 loff1,
2979 struct inode *inode2, u64 loff2, u64 len,
2980 bool retry_range_locking)
2981{
2982 int ret;
2983
2984 if (inode1 < inode2) {
2985 swap(inode1, inode2);
2986 swap(loff1, loff2);
2987 }
2988 ret = lock_extent_range(inode1, loff1, len, retry_range_locking);
2989 if (ret)
2990 return ret;
2991 ret = lock_extent_range(inode2, loff2, len, retry_range_locking);
2992 if (ret)
2993 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1,
2994 loff1 + len - 1);
2995 return ret;
2996}
2997
2998struct cmp_pages {
2999 int num_pages;
3000 struct page **src_pages;
3001 struct page **dst_pages;
3002};
3003
3004static void btrfs_cmp_data_free(struct cmp_pages *cmp)
3005{
3006 int i;
3007 struct page *pg;
3008
3009 for (i = 0; i < cmp->num_pages; i++) {
3010 pg = cmp->src_pages[i];
3011 if (pg) {
3012 unlock_page(pg);
3013 put_page(pg);
3014 }
3015 pg = cmp->dst_pages[i];
3016 if (pg) {
3017 unlock_page(pg);
3018 put_page(pg);
3019 }
3020 }
3021 kfree(cmp->src_pages);
3022 kfree(cmp->dst_pages);
3023}
3024
3025static int btrfs_cmp_data_prepare(struct inode *src, u64 loff,
3026 struct inode *dst, u64 dst_loff,
3027 u64 len, struct cmp_pages *cmp)
3028{
3029 int ret;
3030 int num_pages = PAGE_ALIGN(len) >> PAGE_SHIFT;
3031 struct page **src_pgarr, **dst_pgarr;
3032
3033 /*
3034 * We must gather up all the pages before we initiate our
3035 * extent locking. We use an array for the page pointers. Size
3036 * of the array is bounded by len, which is in turn bounded by
3037 * BTRFS_MAX_DEDUPE_LEN.
3038 */
3039 src_pgarr = kcalloc(num_pages, sizeof(struct page *), GFP_KERNEL);
3040 dst_pgarr = kcalloc(num_pages, sizeof(struct page *), GFP_KERNEL);
3041 if (!src_pgarr || !dst_pgarr) {
3042 kfree(src_pgarr);
3043 kfree(dst_pgarr);
3044 return -ENOMEM;
3045 }
3046 cmp->num_pages = num_pages;
3047 cmp->src_pages = src_pgarr;
3048 cmp->dst_pages = dst_pgarr;
3049
3050 ret = gather_extent_pages(src, cmp->src_pages, cmp->num_pages, loff);
3051 if (ret)
3052 goto out;
3053
3054 ret = gather_extent_pages(dst, cmp->dst_pages, cmp->num_pages, dst_loff);
3055
3056out:
3057 if (ret)
3058 btrfs_cmp_data_free(cmp);
3059 return 0;
3060}
3061
3062static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
3063 u64 dst_loff, u64 len, struct cmp_pages *cmp)
3064{
3065 int ret = 0;
3066 int i;
3067 struct page *src_page, *dst_page;
3068 unsigned int cmp_len = PAGE_SIZE;
3069 void *addr, *dst_addr;
3070
3071 i = 0;
3072 while (len) {
3073 if (len < PAGE_SIZE)
3074 cmp_len = len;
3075
3076 BUG_ON(i >= cmp->num_pages);
3077
3078 src_page = cmp->src_pages[i];
3079 dst_page = cmp->dst_pages[i];
3080 ASSERT(PageLocked(src_page));
3081 ASSERT(PageLocked(dst_page));
3082
3083 addr = kmap_atomic(src_page);
3084 dst_addr = kmap_atomic(dst_page);
3085
3086 flush_dcache_page(src_page);
3087 flush_dcache_page(dst_page);
3088
3089 if (memcmp(addr, dst_addr, cmp_len))
3090 ret = -EBADE;
3091
3092 kunmap_atomic(addr);
3093 kunmap_atomic(dst_addr);
3094
3095 if (ret)
3096 break;
3097
3098 len -= cmp_len;
3099 i++;
3100 }
3101
3102 return ret;
3103}
3104
3105static int extent_same_check_offsets(struct inode *inode, u64 off, u64 *plen,
3106 u64 olen)
3107{
3108 u64 len = *plen;
3109 u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
3110
3111 if (off + olen > inode->i_size || off + olen < off)
3112 return -EINVAL;
3113
3114 /* if we extend to eof, continue to block boundary */
3115 if (off + len == inode->i_size)
3116 *plen = len = ALIGN(inode->i_size, bs) - off;
3117
3118 /* Check that we are block aligned - btrfs_clone() requires this */
3119 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
3120 return -EINVAL;
3121
3122 return 0;
3123}
3124
3125static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
3126 struct inode *dst, u64 dst_loff)
3127{
3128 int ret;
3129 u64 len = olen;
3130 struct cmp_pages cmp;
3131 int same_inode = 0;
3132 u64 same_lock_start = 0;
3133 u64 same_lock_len = 0;
3134
3135 if (src == dst)
3136 same_inode = 1;
3137
3138 if (len == 0)
3139 return 0;
3140
3141 if (same_inode) {
3142 inode_lock(src);
3143
3144 ret = extent_same_check_offsets(src, loff, &len, olen);
3145 if (ret)
3146 goto out_unlock;
3147 ret = extent_same_check_offsets(src, dst_loff, &len, olen);
3148 if (ret)
3149 goto out_unlock;
3150
3151 /*
3152 * Single inode case wants the same checks, except we
3153 * don't want our length pushed out past i_size as
3154 * comparing that data range makes no sense.
3155 *
3156 * extent_same_check_offsets() will do this for an
3157 * unaligned length at i_size, so catch it here and
3158 * reject the request.
3159 *
3160 * This effectively means we require aligned extents
3161 * for the single-inode case, whereas the other cases
3162 * allow an unaligned length so long as it ends at
3163 * i_size.
3164 */
3165 if (len != olen) {
3166 ret = -EINVAL;
3167 goto out_unlock;
3168 }
3169
3170 /* Check for overlapping ranges */
3171 if (dst_loff + len > loff && dst_loff < loff + len) {
3172 ret = -EINVAL;
3173 goto out_unlock;
3174 }
3175
3176 same_lock_start = min_t(u64, loff, dst_loff);
3177 same_lock_len = max_t(u64, loff, dst_loff) + len - same_lock_start;
3178 } else {
3179 btrfs_double_inode_lock(src, dst);
3180
3181 ret = extent_same_check_offsets(src, loff, &len, olen);
3182 if (ret)
3183 goto out_unlock;
3184
3185 ret = extent_same_check_offsets(dst, dst_loff, &len, olen);
3186 if (ret)
3187 goto out_unlock;
3188 }
3189
3190 /* don't make the dst file partly checksummed */
3191 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3192 (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
3193 ret = -EINVAL;
3194 goto out_unlock;
3195 }
3196
3197again:
3198 ret = btrfs_cmp_data_prepare(src, loff, dst, dst_loff, olen, &cmp);
3199 if (ret)
3200 goto out_unlock;
3201
3202 if (same_inode)
3203 ret = lock_extent_range(src, same_lock_start, same_lock_len,
3204 false);
3205 else
3206 ret = btrfs_double_extent_lock(src, loff, dst, dst_loff, len,
3207 false);
3208 /*
3209 * If one of the inodes has dirty pages in the respective range or
3210 * ordered extents, we need to flush dellaloc and wait for all ordered
3211 * extents in the range. We must unlock the pages and the ranges in the
3212 * io trees to avoid deadlocks when flushing delalloc (requires locking
3213 * pages) and when waiting for ordered extents to complete (they require
3214 * range locking).
3215 */
3216 if (ret == -EAGAIN) {
3217 /*
3218 * Ranges in the io trees already unlocked. Now unlock all
3219 * pages before waiting for all IO to complete.
3220 */
3221 btrfs_cmp_data_free(&cmp);
3222 if (same_inode) {
3223 btrfs_wait_ordered_range(src, same_lock_start,
3224 same_lock_len);
3225 } else {
3226 btrfs_wait_ordered_range(src, loff, len);
3227 btrfs_wait_ordered_range(dst, dst_loff, len);
3228 }
3229 goto again;
3230 }
3231 ASSERT(ret == 0);
3232 if (WARN_ON(ret)) {
3233 /* ranges in the io trees already unlocked */
3234 btrfs_cmp_data_free(&cmp);
3235 return ret;
3236 }
3237
3238 /* pass original length for comparison so we stay within i_size */
3239 ret = btrfs_cmp_data(src, loff, dst, dst_loff, olen, &cmp);
3240 if (ret == 0)
3241 ret = btrfs_clone(src, dst, loff, olen, len, dst_loff, 1);
3242
3243 if (same_inode)
3244 unlock_extent(&BTRFS_I(src)->io_tree, same_lock_start,
3245 same_lock_start + same_lock_len - 1);
3246 else
3247 btrfs_double_extent_unlock(src, loff, dst, dst_loff, len);
3248
3249 btrfs_cmp_data_free(&cmp);
3250out_unlock:
3251 if (same_inode)
3252 inode_unlock(src);
3253 else
3254 btrfs_double_inode_unlock(src, dst);
3255
3256 return ret;
3257}
3258
3259#define BTRFS_MAX_DEDUPE_LEN SZ_16M
3260
3261ssize_t btrfs_dedupe_file_range(struct file *src_file, u64 loff, u64 olen,
3262 struct file *dst_file, u64 dst_loff)
3263{
3264 struct inode *src = file_inode(src_file);
3265 struct inode *dst = file_inode(dst_file);
3266 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
3267 ssize_t res;
3268
3269 if (olen > BTRFS_MAX_DEDUPE_LEN)
3270 olen = BTRFS_MAX_DEDUPE_LEN;
3271
3272 if (WARN_ON_ONCE(bs < PAGE_SIZE)) {
3273 /*
3274 * Btrfs does not support blocksize < page_size. As a
3275 * result, btrfs_cmp_data() won't correctly handle
3276 * this situation without an update.
3277 */
3278 return -EINVAL;
3279 }
3280
3281 res = btrfs_extent_same(src, loff, olen, dst, dst_loff);
3282 if (res)
3283 return res;
3284 return olen;
3285}
3286
3287static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3288 struct inode *inode,
3289 u64 endoff,
3290 const u64 destoff,
3291 const u64 olen,
3292 int no_time_update)
3293{
3294 struct btrfs_root *root = BTRFS_I(inode)->root;
3295 int ret;
3296
3297 inode_inc_iversion(inode);
3298 if (!no_time_update)
3299 inode->i_mtime = inode->i_ctime = current_time(inode);
3300 /*
3301 * We round up to the block size at eof when determining which
3302 * extents to clone above, but shouldn't round up the file size.
3303 */
3304 if (endoff > destoff + olen)
3305 endoff = destoff + olen;
3306 if (endoff > inode->i_size)
3307 btrfs_i_size_write(inode, endoff);
3308
3309 ret = btrfs_update_inode(trans, root, inode);
3310 if (ret) {
3311 btrfs_abort_transaction(trans, ret);
3312 btrfs_end_transaction(trans);
3313 goto out;
3314 }
3315 ret = btrfs_end_transaction(trans);
3316out:
3317 return ret;
3318}
3319
3320static void clone_update_extent_map(struct inode *inode,
3321 const struct btrfs_trans_handle *trans,
3322 const struct btrfs_path *path,
3323 const u64 hole_offset,
3324 const u64 hole_len)
3325{
3326 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
3327 struct extent_map *em;
3328 int ret;
3329
3330 em = alloc_extent_map();
3331 if (!em) {
3332 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3333 &BTRFS_I(inode)->runtime_flags);
3334 return;
3335 }
3336
3337 if (path) {
3338 struct btrfs_file_extent_item *fi;
3339
3340 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
3341 struct btrfs_file_extent_item);
3342 btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
3343 em->generation = -1;
3344 if (btrfs_file_extent_type(path->nodes[0], fi) ==
3345 BTRFS_FILE_EXTENT_INLINE)
3346 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3347 &BTRFS_I(inode)->runtime_flags);
3348 } else {
3349 em->start = hole_offset;
3350 em->len = hole_len;
3351 em->ram_bytes = em->len;
3352 em->orig_start = hole_offset;
3353 em->block_start = EXTENT_MAP_HOLE;
3354 em->block_len = 0;
3355 em->orig_block_len = 0;
3356 em->compress_type = BTRFS_COMPRESS_NONE;
3357 em->generation = trans->transid;
3358 }
3359
3360 while (1) {
3361 write_lock(&em_tree->lock);
3362 ret = add_extent_mapping(em_tree, em, 1);
3363 write_unlock(&em_tree->lock);
3364 if (ret != -EEXIST) {
3365 free_extent_map(em);
3366 break;
3367 }
3368 btrfs_drop_extent_cache(inode, em->start,
3369 em->start + em->len - 1, 0);
3370 }
3371
3372 if (ret)
3373 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3374 &BTRFS_I(inode)->runtime_flags);
3375}
3376
3377/*
3378 * Make sure we do not end up inserting an inline extent into a file that has
3379 * already other (non-inline) extents. If a file has an inline extent it can
3380 * not have any other extents and the (single) inline extent must start at the
3381 * file offset 0. Failing to respect these rules will lead to file corruption,
3382 * resulting in EIO errors on read/write operations, hitting BUG_ON's in mm, etc
3383 *
3384 * We can have extents that have been already written to disk or we can have
3385 * dirty ranges still in delalloc, in which case the extent maps and items are
3386 * created only when we run delalloc, and the delalloc ranges might fall outside
3387 * the range we are currently locking in the inode's io tree. So we check the
3388 * inode's i_size because of that (i_size updates are done while holding the
3389 * i_mutex, which we are holding here).
3390 * We also check to see if the inode has a size not greater than "datal" but has
3391 * extents beyond it, due to an fallocate with FALLOC_FL_KEEP_SIZE (and we are
3392 * protected against such concurrent fallocate calls by the i_mutex).
3393 *
3394 * If the file has no extents but a size greater than datal, do not allow the
3395 * copy because we would need turn the inline extent into a non-inline one (even
3396 * with NO_HOLES enabled). If we find our destination inode only has one inline
3397 * extent, just overwrite it with the source inline extent if its size is less
3398 * than the source extent's size, or we could copy the source inline extent's
3399 * data into the destination inode's inline extent if the later is greater then
3400 * the former.
3401 */
3402static int clone_copy_inline_extent(struct inode *src,
3403 struct inode *dst,
3404 struct btrfs_trans_handle *trans,
3405 struct btrfs_path *path,
3406 struct btrfs_key *new_key,
3407 const u64 drop_start,
3408 const u64 datal,
3409 const u64 skip,
3410 const u64 size,
3411 char *inline_data)
3412{
3413 struct btrfs_fs_info *fs_info = btrfs_sb(dst->i_sb);
3414 struct btrfs_root *root = BTRFS_I(dst)->root;
3415 const u64 aligned_end = ALIGN(new_key->offset + datal,
3416 fs_info->sectorsize);
3417 int ret;
3418 struct btrfs_key key;
3419
3420 if (new_key->offset > 0)
3421 return -EOPNOTSUPP;
3422
3423 key.objectid = btrfs_ino(dst);
3424 key.type = BTRFS_EXTENT_DATA_KEY;
3425 key.offset = 0;
3426 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3427 if (ret < 0) {
3428 return ret;
3429 } else if (ret > 0) {
3430 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
3431 ret = btrfs_next_leaf(root, path);
3432 if (ret < 0)
3433 return ret;
3434 else if (ret > 0)
3435 goto copy_inline_extent;
3436 }
3437 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
3438 if (key.objectid == btrfs_ino(dst) &&
3439 key.type == BTRFS_EXTENT_DATA_KEY) {
3440 ASSERT(key.offset > 0);
3441 return -EOPNOTSUPP;
3442 }
3443 } else if (i_size_read(dst) <= datal) {
3444 struct btrfs_file_extent_item *ei;
3445 u64 ext_len;
3446
3447 /*
3448 * If the file size is <= datal, make sure there are no other
3449 * extents following (can happen do to an fallocate call with
3450 * the flag FALLOC_FL_KEEP_SIZE).
3451 */
3452 ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
3453 struct btrfs_file_extent_item);
3454 /*
3455 * If it's an inline extent, it can not have other extents
3456 * following it.
3457 */
3458 if (btrfs_file_extent_type(path->nodes[0], ei) ==
3459 BTRFS_FILE_EXTENT_INLINE)
3460 goto copy_inline_extent;
3461
3462 ext_len = btrfs_file_extent_num_bytes(path->nodes[0], ei);
3463 if (ext_len > aligned_end)
3464 return -EOPNOTSUPP;
3465
3466 ret = btrfs_next_item(root, path);
3467 if (ret < 0) {
3468 return ret;
3469 } else if (ret == 0) {
3470 btrfs_item_key_to_cpu(path->nodes[0], &key,
3471 path->slots[0]);
3472 if (key.objectid == btrfs_ino(dst) &&
3473 key.type == BTRFS_EXTENT_DATA_KEY)
3474 return -EOPNOTSUPP;
3475 }
3476 }
3477
3478copy_inline_extent:
3479 /*
3480 * We have no extent items, or we have an extent at offset 0 which may
3481 * or may not be inlined. All these cases are dealt the same way.
3482 */
3483 if (i_size_read(dst) > datal) {
3484 /*
3485 * If the destination inode has an inline extent...
3486 * This would require copying the data from the source inline
3487 * extent into the beginning of the destination's inline extent.
3488 * But this is really complex, both extents can be compressed
3489 * or just one of them, which would require decompressing and
3490 * re-compressing data (which could increase the new compressed
3491 * size, not allowing the compressed data to fit anymore in an
3492 * inline extent).
3493 * So just don't support this case for now (it should be rare,
3494 * we are not really saving space when cloning inline extents).
3495 */
3496 return -EOPNOTSUPP;
3497 }
3498
3499 btrfs_release_path(path);
3500 ret = btrfs_drop_extents(trans, root, dst, drop_start, aligned_end, 1);
3501 if (ret)
3502 return ret;
3503 ret = btrfs_insert_empty_item(trans, root, path, new_key, size);
3504 if (ret)
3505 return ret;
3506
3507 if (skip) {
3508 const u32 start = btrfs_file_extent_calc_inline_size(0);
3509
3510 memmove(inline_data + start, inline_data + start + skip, datal);
3511 }
3512
3513 write_extent_buffer(path->nodes[0], inline_data,
3514 btrfs_item_ptr_offset(path->nodes[0],
3515 path->slots[0]),
3516 size);
3517 inode_add_bytes(dst, datal);
3518
3519 return 0;
3520}
3521
3522/**
3523 * btrfs_clone() - clone a range from inode file to another
3524 *
3525 * @src: Inode to clone from
3526 * @inode: Inode to clone to
3527 * @off: Offset within source to start clone from
3528 * @olen: Original length, passed by user, of range to clone
3529 * @olen_aligned: Block-aligned value of olen
3530 * @destoff: Offset within @inode to start clone
3531 * @no_time_update: Whether to update mtime/ctime on the target inode
3532 */
3533static int btrfs_clone(struct inode *src, struct inode *inode,
3534 const u64 off, const u64 olen, const u64 olen_aligned,
3535 const u64 destoff, int no_time_update)
3536{
3537 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3538 struct btrfs_root *root = BTRFS_I(inode)->root;
3539 struct btrfs_path *path = NULL;
3540 struct extent_buffer *leaf;
3541 struct btrfs_trans_handle *trans;
3542 char *buf = NULL;
3543 struct btrfs_key key;
3544 u32 nritems;
3545 int slot;
3546 int ret;
3547 const u64 len = olen_aligned;
3548 u64 last_dest_end = destoff;
3549
3550 ret = -ENOMEM;
3551 buf = kmalloc(fs_info->nodesize, GFP_KERNEL | __GFP_NOWARN);
3552 if (!buf) {
3553 buf = vmalloc(fs_info->nodesize);
3554 if (!buf)
3555 return ret;
3556 }
3557
3558 path = btrfs_alloc_path();
3559 if (!path) {
3560 kvfree(buf);
3561 return ret;
3562 }
3563
3564 path->reada = READA_FORWARD;
3565 /* clone data */
3566 key.objectid = btrfs_ino(src);
3567 key.type = BTRFS_EXTENT_DATA_KEY;
3568 key.offset = off;
3569
3570 while (1) {
3571 u64 next_key_min_offset = key.offset + 1;
3572
3573 /*
3574 * note the key will change type as we walk through the
3575 * tree.
3576 */
3577 path->leave_spinning = 1;
3578 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3579 0, 0);
3580 if (ret < 0)
3581 goto out;
3582 /*
3583 * First search, if no extent item that starts at offset off was
3584 * found but the previous item is an extent item, it's possible
3585 * it might overlap our target range, therefore process it.
3586 */
3587 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3588 btrfs_item_key_to_cpu(path->nodes[0], &key,
3589 path->slots[0] - 1);
3590 if (key.type == BTRFS_EXTENT_DATA_KEY)
3591 path->slots[0]--;
3592 }
3593
3594 nritems = btrfs_header_nritems(path->nodes[0]);
3595process_slot:
3596 if (path->slots[0] >= nritems) {
3597 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3598 if (ret < 0)
3599 goto out;
3600 if (ret > 0)
3601 break;
3602 nritems = btrfs_header_nritems(path->nodes[0]);
3603 }
3604 leaf = path->nodes[0];
3605 slot = path->slots[0];
3606
3607 btrfs_item_key_to_cpu(leaf, &key, slot);
3608 if (key.type > BTRFS_EXTENT_DATA_KEY ||
3609 key.objectid != btrfs_ino(src))
3610 break;
3611
3612 if (key.type == BTRFS_EXTENT_DATA_KEY) {
3613 struct btrfs_file_extent_item *extent;
3614 int type;
3615 u32 size;
3616 struct btrfs_key new_key;
3617 u64 disko = 0, diskl = 0;
3618 u64 datao = 0, datal = 0;
3619 u8 comp;
3620 u64 drop_start;
3621
3622 extent = btrfs_item_ptr(leaf, slot,
3623 struct btrfs_file_extent_item);
3624 comp = btrfs_file_extent_compression(leaf, extent);
3625 type = btrfs_file_extent_type(leaf, extent);
3626 if (type == BTRFS_FILE_EXTENT_REG ||
3627 type == BTRFS_FILE_EXTENT_PREALLOC) {
3628 disko = btrfs_file_extent_disk_bytenr(leaf,
3629 extent);
3630 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3631 extent);
3632 datao = btrfs_file_extent_offset(leaf, extent);
3633 datal = btrfs_file_extent_num_bytes(leaf,
3634 extent);
3635 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3636 /* take upper bound, may be compressed */
3637 datal = btrfs_file_extent_ram_bytes(leaf,
3638 extent);
3639 }
3640
3641 /*
3642 * The first search might have left us at an extent
3643 * item that ends before our target range's start, can
3644 * happen if we have holes and NO_HOLES feature enabled.
3645 */
3646 if (key.offset + datal <= off) {
3647 path->slots[0]++;
3648 goto process_slot;
3649 } else if (key.offset >= off + len) {
3650 break;
3651 }
3652 next_key_min_offset = key.offset + datal;
3653 size = btrfs_item_size_nr(leaf, slot);
3654 read_extent_buffer(leaf, buf,
3655 btrfs_item_ptr_offset(leaf, slot),
3656 size);
3657
3658 btrfs_release_path(path);
3659 path->leave_spinning = 0;
3660
3661 memcpy(&new_key, &key, sizeof(new_key));
3662 new_key.objectid = btrfs_ino(inode);
3663 if (off <= key.offset)
3664 new_key.offset = key.offset + destoff - off;
3665 else
3666 new_key.offset = destoff;
3667
3668 /*
3669 * Deal with a hole that doesn't have an extent item
3670 * that represents it (NO_HOLES feature enabled).
3671 * This hole is either in the middle of the cloning
3672 * range or at the beginning (fully overlaps it or
3673 * partially overlaps it).
3674 */
3675 if (new_key.offset != last_dest_end)
3676 drop_start = last_dest_end;
3677 else
3678 drop_start = new_key.offset;
3679
3680 /*
3681 * 1 - adjusting old extent (we may have to split it)
3682 * 1 - add new extent
3683 * 1 - inode update
3684 */
3685 trans = btrfs_start_transaction(root, 3);
3686 if (IS_ERR(trans)) {
3687 ret = PTR_ERR(trans);
3688 goto out;
3689 }
3690
3691 if (type == BTRFS_FILE_EXTENT_REG ||
3692 type == BTRFS_FILE_EXTENT_PREALLOC) {
3693 /*
3694 * a | --- range to clone ---| b
3695 * | ------------- extent ------------- |
3696 */
3697
3698 /* subtract range b */
3699 if (key.offset + datal > off + len)
3700 datal = off + len - key.offset;
3701
3702 /* subtract range a */
3703 if (off > key.offset) {
3704 datao += off - key.offset;
3705 datal -= off - key.offset;
3706 }
3707
3708 ret = btrfs_drop_extents(trans, root, inode,
3709 drop_start,
3710 new_key.offset + datal,
3711 1);
3712 if (ret) {
3713 if (ret != -EOPNOTSUPP)
3714 btrfs_abort_transaction(trans,
3715 ret);
3716 btrfs_end_transaction(trans);
3717 goto out;
3718 }
3719
3720 ret = btrfs_insert_empty_item(trans, root, path,
3721 &new_key, size);
3722 if (ret) {
3723 btrfs_abort_transaction(trans, ret);
3724 btrfs_end_transaction(trans);
3725 goto out;
3726 }
3727
3728 leaf = path->nodes[0];
3729 slot = path->slots[0];
3730 write_extent_buffer(leaf, buf,
3731 btrfs_item_ptr_offset(leaf, slot),
3732 size);
3733
3734 extent = btrfs_item_ptr(leaf, slot,
3735 struct btrfs_file_extent_item);
3736
3737 /* disko == 0 means it's a hole */
3738 if (!disko)
3739 datao = 0;
3740
3741 btrfs_set_file_extent_offset(leaf, extent,
3742 datao);
3743 btrfs_set_file_extent_num_bytes(leaf, extent,
3744 datal);
3745
3746 if (disko) {
3747 inode_add_bytes(inode, datal);
3748 ret = btrfs_inc_extent_ref(trans,
3749 fs_info,
3750 disko, diskl, 0,
3751 root->root_key.objectid,
3752 btrfs_ino(inode),
3753 new_key.offset - datao);
3754 if (ret) {
3755 btrfs_abort_transaction(trans,
3756 ret);
3757 btrfs_end_transaction(trans);
3758 goto out;
3759
3760 }
3761 }
3762 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3763 u64 skip = 0;
3764 u64 trim = 0;
3765
3766 if (off > key.offset) {
3767 skip = off - key.offset;
3768 new_key.offset += skip;
3769 }
3770
3771 if (key.offset + datal > off + len)
3772 trim = key.offset + datal - (off + len);
3773
3774 if (comp && (skip || trim)) {
3775 ret = -EINVAL;
3776 btrfs_end_transaction(trans);
3777 goto out;
3778 }
3779 size -= skip + trim;
3780 datal -= skip + trim;
3781
3782 ret = clone_copy_inline_extent(src, inode,
3783 trans, path,
3784 &new_key,
3785 drop_start,
3786 datal,
3787 skip, size, buf);
3788 if (ret) {
3789 if (ret != -EOPNOTSUPP)
3790 btrfs_abort_transaction(trans,
3791 ret);
3792 btrfs_end_transaction(trans);
3793 goto out;
3794 }
3795 leaf = path->nodes[0];
3796 slot = path->slots[0];
3797 }
3798
3799 /* If we have an implicit hole (NO_HOLES feature). */
3800 if (drop_start < new_key.offset)
3801 clone_update_extent_map(inode, trans,
3802 NULL, drop_start,
3803 new_key.offset - drop_start);
3804
3805 clone_update_extent_map(inode, trans, path, 0, 0);
3806
3807 btrfs_mark_buffer_dirty(leaf);
3808 btrfs_release_path(path);
3809
3810 last_dest_end = ALIGN(new_key.offset + datal,
3811 fs_info->sectorsize);
3812 ret = clone_finish_inode_update(trans, inode,
3813 last_dest_end,
3814 destoff, olen,
3815 no_time_update);
3816 if (ret)
3817 goto out;
3818 if (new_key.offset + datal >= destoff + len)
3819 break;
3820 }
3821 btrfs_release_path(path);
3822 key.offset = next_key_min_offset;
3823
3824 if (fatal_signal_pending(current)) {
3825 ret = -EINTR;
3826 goto out;
3827 }
3828 }
3829 ret = 0;
3830
3831 if (last_dest_end < destoff + len) {
3832 /*
3833 * We have an implicit hole (NO_HOLES feature is enabled) that
3834 * fully or partially overlaps our cloning range at its end.
3835 */
3836 btrfs_release_path(path);
3837
3838 /*
3839 * 1 - remove extent(s)
3840 * 1 - inode update
3841 */
3842 trans = btrfs_start_transaction(root, 2);
3843 if (IS_ERR(trans)) {
3844 ret = PTR_ERR(trans);
3845 goto out;
3846 }
3847 ret = btrfs_drop_extents(trans, root, inode,
3848 last_dest_end, destoff + len, 1);
3849 if (ret) {
3850 if (ret != -EOPNOTSUPP)
3851 btrfs_abort_transaction(trans, ret);
3852 btrfs_end_transaction(trans);
3853 goto out;
3854 }
3855 clone_update_extent_map(inode, trans, NULL, last_dest_end,
3856 destoff + len - last_dest_end);
3857 ret = clone_finish_inode_update(trans, inode, destoff + len,
3858 destoff, olen, no_time_update);
3859 }
3860
3861out:
3862 btrfs_free_path(path);
3863 kvfree(buf);
3864 return ret;
3865}
3866
3867static noinline int btrfs_clone_files(struct file *file, struct file *file_src,
3868 u64 off, u64 olen, u64 destoff)
3869{
3870 struct inode *inode = file_inode(file);
3871 struct inode *src = file_inode(file_src);
3872 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3873 struct btrfs_root *root = BTRFS_I(inode)->root;
3874 int ret;
3875 u64 len = olen;
3876 u64 bs = fs_info->sb->s_blocksize;
3877 int same_inode = src == inode;
3878
3879 /*
3880 * TODO:
3881 * - split compressed inline extents. annoying: we need to
3882 * decompress into destination's address_space (the file offset
3883 * may change, so source mapping won't do), then recompress (or
3884 * otherwise reinsert) a subrange.
3885 *
3886 * - split destination inode's inline extents. The inline extents can
3887 * be either compressed or non-compressed.
3888 */
3889
3890 if (btrfs_root_readonly(root))
3891 return -EROFS;
3892
3893 if (file_src->f_path.mnt != file->f_path.mnt ||
3894 src->i_sb != inode->i_sb)
3895 return -EXDEV;
3896
3897 /* don't make the dst file partly checksummed */
3898 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3899 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3900 return -EINVAL;
3901
3902 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3903 return -EISDIR;
3904
3905 if (!same_inode) {
3906 btrfs_double_inode_lock(src, inode);
3907 } else {
3908 inode_lock(src);
3909 }
3910
3911 /* determine range to clone */
3912 ret = -EINVAL;
3913 if (off + len > src->i_size || off + len < off)
3914 goto out_unlock;
3915 if (len == 0)
3916 olen = len = src->i_size - off;
3917 /* if we extend to eof, continue to block boundary */
3918 if (off + len == src->i_size)
3919 len = ALIGN(src->i_size, bs) - off;
3920
3921 if (len == 0) {
3922 ret = 0;
3923 goto out_unlock;
3924 }
3925
3926 /* verify the end result is block aligned */
3927 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
3928 !IS_ALIGNED(destoff, bs))
3929 goto out_unlock;
3930
3931 /* verify if ranges are overlapped within the same file */
3932 if (same_inode) {
3933 if (destoff + len > off && destoff < off + len)
3934 goto out_unlock;
3935 }
3936
3937 if (destoff > inode->i_size) {
3938 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3939 if (ret)
3940 goto out_unlock;
3941 }
3942
3943 /*
3944 * Lock the target range too. Right after we replace the file extent
3945 * items in the fs tree (which now point to the cloned data), we might
3946 * have a worker replace them with extent items relative to a write
3947 * operation that was issued before this clone operation (i.e. confront
3948 * with inode.c:btrfs_finish_ordered_io).
3949 */
3950 if (same_inode) {
3951 u64 lock_start = min_t(u64, off, destoff);
3952 u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
3953
3954 ret = lock_extent_range(src, lock_start, lock_len, true);
3955 } else {
3956 ret = btrfs_double_extent_lock(src, off, inode, destoff, len,
3957 true);
3958 }
3959 ASSERT(ret == 0);
3960 if (WARN_ON(ret)) {
3961 /* ranges in the io trees already unlocked */
3962 goto out_unlock;
3963 }
3964
3965 ret = btrfs_clone(src, inode, off, olen, len, destoff, 0);
3966
3967 if (same_inode) {
3968 u64 lock_start = min_t(u64, off, destoff);
3969 u64 lock_end = max_t(u64, off, destoff) + len - 1;
3970
3971 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
3972 } else {
3973 btrfs_double_extent_unlock(src, off, inode, destoff, len);
3974 }
3975 /*
3976 * Truncate page cache pages so that future reads will see the cloned
3977 * data immediately and not the previous data.
3978 */
3979 truncate_inode_pages_range(&inode->i_data,
3980 round_down(destoff, PAGE_SIZE),
3981 round_up(destoff + len, PAGE_SIZE) - 1);
3982out_unlock:
3983 if (!same_inode)
3984 btrfs_double_inode_unlock(src, inode);
3985 else
3986 inode_unlock(src);
3987 return ret;
3988}
3989
3990int btrfs_clone_file_range(struct file *src_file, loff_t off,
3991 struct file *dst_file, loff_t destoff, u64 len)
3992{
3993 return btrfs_clone_files(dst_file, src_file, off, len, destoff);
3994}
3995
3996/*
3997 * there are many ways the trans_start and trans_end ioctls can lead
3998 * to deadlocks. They should only be used by applications that
3999 * basically own the machine, and have a very in depth understanding
4000 * of all the possible deadlocks and enospc problems.
4001 */
4002static long btrfs_ioctl_trans_start(struct file *file)
4003{
4004 struct inode *inode = file_inode(file);
4005 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4006 struct btrfs_root *root = BTRFS_I(inode)->root;
4007 struct btrfs_trans_handle *trans;
4008 int ret;
4009
4010 ret = -EPERM;
4011 if (!capable(CAP_SYS_ADMIN))
4012 goto out;
4013
4014 ret = -EINPROGRESS;
4015 if (file->private_data)
4016 goto out;
4017
4018 ret = -EROFS;
4019 if (btrfs_root_readonly(root))
4020 goto out;
4021
4022 ret = mnt_want_write_file(file);
4023 if (ret)
4024 goto out;
4025
4026 atomic_inc(&fs_info->open_ioctl_trans);
4027
4028 ret = -ENOMEM;
4029 trans = btrfs_start_ioctl_transaction(root);
4030 if (IS_ERR(trans))
4031 goto out_drop;
4032
4033 file->private_data = trans;
4034 return 0;
4035
4036out_drop:
4037 atomic_dec(&fs_info->open_ioctl_trans);
4038 mnt_drop_write_file(file);
4039out:
4040 return ret;
4041}
4042
4043static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
4044{
4045 struct inode *inode = file_inode(file);
4046 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4047 struct btrfs_root *root = BTRFS_I(inode)->root;
4048 struct btrfs_root *new_root;
4049 struct btrfs_dir_item *di;
4050 struct btrfs_trans_handle *trans;
4051 struct btrfs_path *path;
4052 struct btrfs_key location;
4053 struct btrfs_disk_key disk_key;
4054 u64 objectid = 0;
4055 u64 dir_id;
4056 int ret;
4057
4058 if (!capable(CAP_SYS_ADMIN))
4059 return -EPERM;
4060
4061 ret = mnt_want_write_file(file);
4062 if (ret)
4063 return ret;
4064
4065 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
4066 ret = -EFAULT;
4067 goto out;
4068 }
4069
4070 if (!objectid)
4071 objectid = BTRFS_FS_TREE_OBJECTID;
4072
4073 location.objectid = objectid;
4074 location.type = BTRFS_ROOT_ITEM_KEY;
4075 location.offset = (u64)-1;
4076
4077 new_root = btrfs_read_fs_root_no_name(fs_info, &location);
4078 if (IS_ERR(new_root)) {
4079 ret = PTR_ERR(new_root);
4080 goto out;
4081 }
4082
4083 path = btrfs_alloc_path();
4084 if (!path) {
4085 ret = -ENOMEM;
4086 goto out;
4087 }
4088 path->leave_spinning = 1;
4089
4090 trans = btrfs_start_transaction(root, 1);
4091 if (IS_ERR(trans)) {
4092 btrfs_free_path(path);
4093 ret = PTR_ERR(trans);
4094 goto out;
4095 }
4096
4097 dir_id = btrfs_super_root_dir(fs_info->super_copy);
4098 di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
4099 dir_id, "default", 7, 1);
4100 if (IS_ERR_OR_NULL(di)) {
4101 btrfs_free_path(path);
4102 btrfs_end_transaction(trans);
4103 btrfs_err(fs_info,
4104 "Umm, you don't have the default diritem, this isn't going to work");
4105 ret = -ENOENT;
4106 goto out;
4107 }
4108
4109 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
4110 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
4111 btrfs_mark_buffer_dirty(path->nodes[0]);
4112 btrfs_free_path(path);
4113
4114 btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
4115 btrfs_end_transaction(trans);
4116out:
4117 mnt_drop_write_file(file);
4118 return ret;
4119}
4120
4121void btrfs_get_block_group_info(struct list_head *groups_list,
4122 struct btrfs_ioctl_space_info *space)
4123{
4124 struct btrfs_block_group_cache *block_group;
4125
4126 space->total_bytes = 0;
4127 space->used_bytes = 0;
4128 space->flags = 0;
4129 list_for_each_entry(block_group, groups_list, list) {
4130 space->flags = block_group->flags;
4131 space->total_bytes += block_group->key.offset;
4132 space->used_bytes +=
4133 btrfs_block_group_used(&block_group->item);
4134 }
4135}
4136
4137static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
4138 void __user *arg)
4139{
4140 struct btrfs_ioctl_space_args space_args;
4141 struct btrfs_ioctl_space_info space;
4142 struct btrfs_ioctl_space_info *dest;
4143 struct btrfs_ioctl_space_info *dest_orig;
4144 struct btrfs_ioctl_space_info __user *user_dest;
4145 struct btrfs_space_info *info;
4146 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
4147 BTRFS_BLOCK_GROUP_SYSTEM,
4148 BTRFS_BLOCK_GROUP_METADATA,
4149 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
4150 int num_types = 4;
4151 int alloc_size;
4152 int ret = 0;
4153 u64 slot_count = 0;
4154 int i, c;
4155
4156 if (copy_from_user(&space_args,
4157 (struct btrfs_ioctl_space_args __user *)arg,
4158 sizeof(space_args)))
4159 return -EFAULT;
4160
4161 for (i = 0; i < num_types; i++) {
4162 struct btrfs_space_info *tmp;
4163
4164 info = NULL;
4165 rcu_read_lock();
4166 list_for_each_entry_rcu(tmp, &fs_info->space_info,
4167 list) {
4168 if (tmp->flags == types[i]) {
4169 info = tmp;
4170 break;
4171 }
4172 }
4173 rcu_read_unlock();
4174
4175 if (!info)
4176 continue;
4177
4178 down_read(&info->groups_sem);
4179 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4180 if (!list_empty(&info->block_groups[c]))
4181 slot_count++;
4182 }
4183 up_read(&info->groups_sem);
4184 }
4185
4186 /*
4187 * Global block reserve, exported as a space_info
4188 */
4189 slot_count++;
4190
4191 /* space_slots == 0 means they are asking for a count */
4192 if (space_args.space_slots == 0) {
4193 space_args.total_spaces = slot_count;
4194 goto out;
4195 }
4196
4197 slot_count = min_t(u64, space_args.space_slots, slot_count);
4198
4199 alloc_size = sizeof(*dest) * slot_count;
4200
4201 /* we generally have at most 6 or so space infos, one for each raid
4202 * level. So, a whole page should be more than enough for everyone
4203 */
4204 if (alloc_size > PAGE_SIZE)
4205 return -ENOMEM;
4206
4207 space_args.total_spaces = 0;
4208 dest = kmalloc(alloc_size, GFP_KERNEL);
4209 if (!dest)
4210 return -ENOMEM;
4211 dest_orig = dest;
4212
4213 /* now we have a buffer to copy into */
4214 for (i = 0; i < num_types; i++) {
4215 struct btrfs_space_info *tmp;
4216
4217 if (!slot_count)
4218 break;
4219
4220 info = NULL;
4221 rcu_read_lock();
4222 list_for_each_entry_rcu(tmp, &fs_info->space_info,
4223 list) {
4224 if (tmp->flags == types[i]) {
4225 info = tmp;
4226 break;
4227 }
4228 }
4229 rcu_read_unlock();
4230
4231 if (!info)
4232 continue;
4233 down_read(&info->groups_sem);
4234 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4235 if (!list_empty(&info->block_groups[c])) {
4236 btrfs_get_block_group_info(
4237 &info->block_groups[c], &space);
4238 memcpy(dest, &space, sizeof(space));
4239 dest++;
4240 space_args.total_spaces++;
4241 slot_count--;
4242 }
4243 if (!slot_count)
4244 break;
4245 }
4246 up_read(&info->groups_sem);
4247 }
4248
4249 /*
4250 * Add global block reserve
4251 */
4252 if (slot_count) {
4253 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
4254
4255 spin_lock(&block_rsv->lock);
4256 space.total_bytes = block_rsv->size;
4257 space.used_bytes = block_rsv->size - block_rsv->reserved;
4258 spin_unlock(&block_rsv->lock);
4259 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
4260 memcpy(dest, &space, sizeof(space));
4261 space_args.total_spaces++;
4262 }
4263
4264 user_dest = (struct btrfs_ioctl_space_info __user *)
4265 (arg + sizeof(struct btrfs_ioctl_space_args));
4266
4267 if (copy_to_user(user_dest, dest_orig, alloc_size))
4268 ret = -EFAULT;
4269
4270 kfree(dest_orig);
4271out:
4272 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4273 ret = -EFAULT;
4274
4275 return ret;
4276}
4277
4278/*
4279 * there are many ways the trans_start and trans_end ioctls can lead
4280 * to deadlocks. They should only be used by applications that
4281 * basically own the machine, and have a very in depth understanding
4282 * of all the possible deadlocks and enospc problems.
4283 */
4284long btrfs_ioctl_trans_end(struct file *file)
4285{
4286 struct inode *inode = file_inode(file);
4287 struct btrfs_root *root = BTRFS_I(inode)->root;
4288 struct btrfs_trans_handle *trans;
4289
4290 trans = file->private_data;
4291 if (!trans)
4292 return -EINVAL;
4293 file->private_data = NULL;
4294
4295 btrfs_end_transaction(trans);
4296
4297 atomic_dec(&root->fs_info->open_ioctl_trans);
4298
4299 mnt_drop_write_file(file);
4300 return 0;
4301}
4302
4303static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4304 void __user *argp)
4305{
4306 struct btrfs_trans_handle *trans;
4307 u64 transid;
4308 int ret;
4309
4310 trans = btrfs_attach_transaction_barrier(root);
4311 if (IS_ERR(trans)) {
4312 if (PTR_ERR(trans) != -ENOENT)
4313 return PTR_ERR(trans);
4314
4315 /* No running transaction, don't bother */
4316 transid = root->fs_info->last_trans_committed;
4317 goto out;
4318 }
4319 transid = trans->transid;
4320 ret = btrfs_commit_transaction_async(trans, 0);
4321 if (ret) {
4322 btrfs_end_transaction(trans);
4323 return ret;
4324 }
4325out:
4326 if (argp)
4327 if (copy_to_user(argp, &transid, sizeof(transid)))
4328 return -EFAULT;
4329 return 0;
4330}
4331
4332static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,
4333 void __user *argp)
4334{
4335 u64 transid;
4336
4337 if (argp) {
4338 if (copy_from_user(&transid, argp, sizeof(transid)))
4339 return -EFAULT;
4340 } else {
4341 transid = 0; /* current trans */
4342 }
4343 return btrfs_wait_for_commit(fs_info, transid);
4344}
4345
4346static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4347{
4348 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
4349 struct btrfs_ioctl_scrub_args *sa;
4350 int ret;
4351
4352 if (!capable(CAP_SYS_ADMIN))
4353 return -EPERM;
4354
4355 sa = memdup_user(arg, sizeof(*sa));
4356 if (IS_ERR(sa))
4357 return PTR_ERR(sa);
4358
4359 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4360 ret = mnt_want_write_file(file);
4361 if (ret)
4362 goto out;
4363 }
4364
4365 ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,
4366 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4367 0);
4368
4369 if (copy_to_user(arg, sa, sizeof(*sa)))
4370 ret = -EFAULT;
4371
4372 if (!(sa->flags & BTRFS_SCRUB_READONLY))
4373 mnt_drop_write_file(file);
4374out:
4375 kfree(sa);
4376 return ret;
4377}
4378
4379static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)
4380{
4381 if (!capable(CAP_SYS_ADMIN))
4382 return -EPERM;
4383
4384 return btrfs_scrub_cancel(fs_info);
4385}
4386
4387static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
4388 void __user *arg)
4389{
4390 struct btrfs_ioctl_scrub_args *sa;
4391 int ret;
4392
4393 if (!capable(CAP_SYS_ADMIN))
4394 return -EPERM;
4395
4396 sa = memdup_user(arg, sizeof(*sa));
4397 if (IS_ERR(sa))
4398 return PTR_ERR(sa);
4399
4400 ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
4401
4402 if (copy_to_user(arg, sa, sizeof(*sa)))
4403 ret = -EFAULT;
4404
4405 kfree(sa);
4406 return ret;
4407}
4408
4409static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
4410 void __user *arg)
4411{
4412 struct btrfs_ioctl_get_dev_stats *sa;
4413 int ret;
4414
4415 sa = memdup_user(arg, sizeof(*sa));
4416 if (IS_ERR(sa))
4417 return PTR_ERR(sa);
4418
4419 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4420 kfree(sa);
4421 return -EPERM;
4422 }
4423
4424 ret = btrfs_get_dev_stats(fs_info, sa);
4425
4426 if (copy_to_user(arg, sa, sizeof(*sa)))
4427 ret = -EFAULT;
4428
4429 kfree(sa);
4430 return ret;
4431}
4432
4433static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
4434 void __user *arg)
4435{
4436 struct btrfs_ioctl_dev_replace_args *p;
4437 int ret;
4438
4439 if (!capable(CAP_SYS_ADMIN))
4440 return -EPERM;
4441
4442 p = memdup_user(arg, sizeof(*p));
4443 if (IS_ERR(p))
4444 return PTR_ERR(p);
4445
4446 switch (p->cmd) {
4447 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4448 if (fs_info->sb->s_flags & MS_RDONLY) {
4449 ret = -EROFS;
4450 goto out;
4451 }
4452 if (atomic_xchg(
4453 &fs_info->mutually_exclusive_operation_running, 1)) {
4454 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4455 } else {
4456 ret = btrfs_dev_replace_by_ioctl(fs_info, p);
4457 atomic_set(
4458 &fs_info->mutually_exclusive_operation_running, 0);
4459 }
4460 break;
4461 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4462 btrfs_dev_replace_status(fs_info, p);
4463 ret = 0;
4464 break;
4465 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4466 ret = btrfs_dev_replace_cancel(fs_info, p);
4467 break;
4468 default:
4469 ret = -EINVAL;
4470 break;
4471 }
4472
4473 if (copy_to_user(arg, p, sizeof(*p)))
4474 ret = -EFAULT;
4475out:
4476 kfree(p);
4477 return ret;
4478}
4479
4480static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4481{
4482 int ret = 0;
4483 int i;
4484 u64 rel_ptr;
4485 int size;
4486 struct btrfs_ioctl_ino_path_args *ipa = NULL;
4487 struct inode_fs_paths *ipath = NULL;
4488 struct btrfs_path *path;
4489
4490 if (!capable(CAP_DAC_READ_SEARCH))
4491 return -EPERM;
4492
4493 path = btrfs_alloc_path();
4494 if (!path) {
4495 ret = -ENOMEM;
4496 goto out;
4497 }
4498
4499 ipa = memdup_user(arg, sizeof(*ipa));
4500 if (IS_ERR(ipa)) {
4501 ret = PTR_ERR(ipa);
4502 ipa = NULL;
4503 goto out;
4504 }
4505
4506 size = min_t(u32, ipa->size, 4096);
4507 ipath = init_ipath(size, root, path);
4508 if (IS_ERR(ipath)) {
4509 ret = PTR_ERR(ipath);
4510 ipath = NULL;
4511 goto out;
4512 }
4513
4514 ret = paths_from_inode(ipa->inum, ipath);
4515 if (ret < 0)
4516 goto out;
4517
4518 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4519 rel_ptr = ipath->fspath->val[i] -
4520 (u64)(unsigned long)ipath->fspath->val;
4521 ipath->fspath->val[i] = rel_ptr;
4522 }
4523
4524 ret = copy_to_user((void *)(unsigned long)ipa->fspath,
4525 (void *)(unsigned long)ipath->fspath, size);
4526 if (ret) {
4527 ret = -EFAULT;
4528 goto out;
4529 }
4530
4531out:
4532 btrfs_free_path(path);
4533 free_ipath(ipath);
4534 kfree(ipa);
4535
4536 return ret;
4537}
4538
4539static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4540{
4541 struct btrfs_data_container *inodes = ctx;
4542 const size_t c = 3 * sizeof(u64);
4543
4544 if (inodes->bytes_left >= c) {
4545 inodes->bytes_left -= c;
4546 inodes->val[inodes->elem_cnt] = inum;
4547 inodes->val[inodes->elem_cnt + 1] = offset;
4548 inodes->val[inodes->elem_cnt + 2] = root;
4549 inodes->elem_cnt += 3;
4550 } else {
4551 inodes->bytes_missing += c - inodes->bytes_left;
4552 inodes->bytes_left = 0;
4553 inodes->elem_missed += 3;
4554 }
4555
4556 return 0;
4557}
4558
4559static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,
4560 void __user *arg)
4561{
4562 int ret = 0;
4563 int size;
4564 struct btrfs_ioctl_logical_ino_args *loi;
4565 struct btrfs_data_container *inodes = NULL;
4566 struct btrfs_path *path = NULL;
4567
4568 if (!capable(CAP_SYS_ADMIN))
4569 return -EPERM;
4570
4571 loi = memdup_user(arg, sizeof(*loi));
4572 if (IS_ERR(loi))
4573 return PTR_ERR(loi);
4574
4575 path = btrfs_alloc_path();
4576 if (!path) {
4577 ret = -ENOMEM;
4578 goto out;
4579 }
4580
4581 size = min_t(u32, loi->size, SZ_64K);
4582 inodes = init_data_container(size);
4583 if (IS_ERR(inodes)) {
4584 ret = PTR_ERR(inodes);
4585 inodes = NULL;
4586 goto out;
4587 }
4588
4589 ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
4590 build_ino_list, inodes);
4591 if (ret == -EINVAL)
4592 ret = -ENOENT;
4593 if (ret < 0)
4594 goto out;
4595
4596 ret = copy_to_user((void *)(unsigned long)loi->inodes,
4597 (void *)(unsigned long)inodes, size);
4598 if (ret)
4599 ret = -EFAULT;
4600
4601out:
4602 btrfs_free_path(path);
4603 vfree(inodes);
4604 kfree(loi);
4605
4606 return ret;
4607}
4608
4609void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
4610 struct btrfs_ioctl_balance_args *bargs)
4611{
4612 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4613
4614 bargs->flags = bctl->flags;
4615
4616 if (atomic_read(&fs_info->balance_running))
4617 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4618 if (atomic_read(&fs_info->balance_pause_req))
4619 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4620 if (atomic_read(&fs_info->balance_cancel_req))
4621 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4622
4623 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4624 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4625 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4626
4627 if (lock) {
4628 spin_lock(&fs_info->balance_lock);
4629 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4630 spin_unlock(&fs_info->balance_lock);
4631 } else {
4632 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4633 }
4634}
4635
4636static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4637{
4638 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4639 struct btrfs_fs_info *fs_info = root->fs_info;
4640 struct btrfs_ioctl_balance_args *bargs;
4641 struct btrfs_balance_control *bctl;
4642 bool need_unlock; /* for mut. excl. ops lock */
4643 int ret;
4644
4645 if (!capable(CAP_SYS_ADMIN))
4646 return -EPERM;
4647
4648 ret = mnt_want_write_file(file);
4649 if (ret)
4650 return ret;
4651
4652again:
4653 if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
4654 mutex_lock(&fs_info->volume_mutex);
4655 mutex_lock(&fs_info->balance_mutex);
4656 need_unlock = true;
4657 goto locked;
4658 }
4659
4660 /*
4661 * mut. excl. ops lock is locked. Three possibilities:
4662 * (1) some other op is running
4663 * (2) balance is running
4664 * (3) balance is paused -- special case (think resume)
4665 */
4666 mutex_lock(&fs_info->balance_mutex);
4667 if (fs_info->balance_ctl) {
4668 /* this is either (2) or (3) */
4669 if (!atomic_read(&fs_info->balance_running)) {
4670 mutex_unlock(&fs_info->balance_mutex);
4671 if (!mutex_trylock(&fs_info->volume_mutex))
4672 goto again;
4673 mutex_lock(&fs_info->balance_mutex);
4674
4675 if (fs_info->balance_ctl &&
4676 !atomic_read(&fs_info->balance_running)) {
4677 /* this is (3) */
4678 need_unlock = false;
4679 goto locked;
4680 }
4681
4682 mutex_unlock(&fs_info->balance_mutex);
4683 mutex_unlock(&fs_info->volume_mutex);
4684 goto again;
4685 } else {
4686 /* this is (2) */
4687 mutex_unlock(&fs_info->balance_mutex);
4688 ret = -EINPROGRESS;
4689 goto out;
4690 }
4691 } else {
4692 /* this is (1) */
4693 mutex_unlock(&fs_info->balance_mutex);
4694 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4695 goto out;
4696 }
4697
4698locked:
4699 BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4700
4701 if (arg) {
4702 bargs = memdup_user(arg, sizeof(*bargs));
4703 if (IS_ERR(bargs)) {
4704 ret = PTR_ERR(bargs);
4705 goto out_unlock;
4706 }
4707
4708 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4709 if (!fs_info->balance_ctl) {
4710 ret = -ENOTCONN;
4711 goto out_bargs;
4712 }
4713
4714 bctl = fs_info->balance_ctl;
4715 spin_lock(&fs_info->balance_lock);
4716 bctl->flags |= BTRFS_BALANCE_RESUME;
4717 spin_unlock(&fs_info->balance_lock);
4718
4719 goto do_balance;
4720 }
4721 } else {
4722 bargs = NULL;
4723 }
4724
4725 if (fs_info->balance_ctl) {
4726 ret = -EINPROGRESS;
4727 goto out_bargs;
4728 }
4729
4730 bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
4731 if (!bctl) {
4732 ret = -ENOMEM;
4733 goto out_bargs;
4734 }
4735
4736 bctl->fs_info = fs_info;
4737 if (arg) {
4738 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4739 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4740 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4741
4742 bctl->flags = bargs->flags;
4743 } else {
4744 /* balance everything - no filters */
4745 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4746 }
4747
4748 if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
4749 ret = -EINVAL;
4750 goto out_bctl;
4751 }
4752
4753do_balance:
4754 /*
4755 * Ownership of bctl and mutually_exclusive_operation_running
4756 * goes to to btrfs_balance. bctl is freed in __cancel_balance,
4757 * or, if restriper was paused all the way until unmount, in
4758 * free_fs_info. mutually_exclusive_operation_running is
4759 * cleared in __cancel_balance.
4760 */
4761 need_unlock = false;
4762
4763 ret = btrfs_balance(bctl, bargs);
4764 bctl = NULL;
4765
4766 if (arg) {
4767 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4768 ret = -EFAULT;
4769 }
4770
4771out_bctl:
4772 kfree(bctl);
4773out_bargs:
4774 kfree(bargs);
4775out_unlock:
4776 mutex_unlock(&fs_info->balance_mutex);
4777 mutex_unlock(&fs_info->volume_mutex);
4778 if (need_unlock)
4779 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
4780out:
4781 mnt_drop_write_file(file);
4782 return ret;
4783}
4784
4785static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
4786{
4787 if (!capable(CAP_SYS_ADMIN))
4788 return -EPERM;
4789
4790 switch (cmd) {
4791 case BTRFS_BALANCE_CTL_PAUSE:
4792 return btrfs_pause_balance(fs_info);
4793 case BTRFS_BALANCE_CTL_CANCEL:
4794 return btrfs_cancel_balance(fs_info);
4795 }
4796
4797 return -EINVAL;
4798}
4799
4800static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
4801 void __user *arg)
4802{
4803 struct btrfs_ioctl_balance_args *bargs;
4804 int ret = 0;
4805
4806 if (!capable(CAP_SYS_ADMIN))
4807 return -EPERM;
4808
4809 mutex_lock(&fs_info->balance_mutex);
4810 if (!fs_info->balance_ctl) {
4811 ret = -ENOTCONN;
4812 goto out;
4813 }
4814
4815 bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
4816 if (!bargs) {
4817 ret = -ENOMEM;
4818 goto out;
4819 }
4820
4821 update_ioctl_balance_args(fs_info, 1, bargs);
4822
4823 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4824 ret = -EFAULT;
4825
4826 kfree(bargs);
4827out:
4828 mutex_unlock(&fs_info->balance_mutex);
4829 return ret;
4830}
4831
4832static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4833{
4834 struct inode *inode = file_inode(file);
4835 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4836 struct btrfs_ioctl_quota_ctl_args *sa;
4837 struct btrfs_trans_handle *trans = NULL;
4838 int ret;
4839 int err;
4840
4841 if (!capable(CAP_SYS_ADMIN))
4842 return -EPERM;
4843
4844 ret = mnt_want_write_file(file);
4845 if (ret)
4846 return ret;
4847
4848 sa = memdup_user(arg, sizeof(*sa));
4849 if (IS_ERR(sa)) {
4850 ret = PTR_ERR(sa);
4851 goto drop_write;
4852 }
4853
4854 down_write(&fs_info->subvol_sem);
4855 trans = btrfs_start_transaction(fs_info->tree_root, 2);
4856 if (IS_ERR(trans)) {
4857 ret = PTR_ERR(trans);
4858 goto out;
4859 }
4860
4861 switch (sa->cmd) {
4862 case BTRFS_QUOTA_CTL_ENABLE:
4863 ret = btrfs_quota_enable(trans, fs_info);
4864 break;
4865 case BTRFS_QUOTA_CTL_DISABLE:
4866 ret = btrfs_quota_disable(trans, fs_info);
4867 break;
4868 default:
4869 ret = -EINVAL;
4870 break;
4871 }
4872
4873 err = btrfs_commit_transaction(trans);
4874 if (err && !ret)
4875 ret = err;
4876out:
4877 kfree(sa);
4878 up_write(&fs_info->subvol_sem);
4879drop_write:
4880 mnt_drop_write_file(file);
4881 return ret;
4882}
4883
4884static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4885{
4886 struct inode *inode = file_inode(file);
4887 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4888 struct btrfs_root *root = BTRFS_I(inode)->root;
4889 struct btrfs_ioctl_qgroup_assign_args *sa;
4890 struct btrfs_trans_handle *trans;
4891 int ret;
4892 int err;
4893
4894 if (!capable(CAP_SYS_ADMIN))
4895 return -EPERM;
4896
4897 ret = mnt_want_write_file(file);
4898 if (ret)
4899 return ret;
4900
4901 sa = memdup_user(arg, sizeof(*sa));
4902 if (IS_ERR(sa)) {
4903 ret = PTR_ERR(sa);
4904 goto drop_write;
4905 }
4906
4907 trans = btrfs_join_transaction(root);
4908 if (IS_ERR(trans)) {
4909 ret = PTR_ERR(trans);
4910 goto out;
4911 }
4912
4913 /* FIXME: check if the IDs really exist */
4914 if (sa->assign) {
4915 ret = btrfs_add_qgroup_relation(trans, fs_info,
4916 sa->src, sa->dst);
4917 } else {
4918 ret = btrfs_del_qgroup_relation(trans, fs_info,
4919 sa->src, sa->dst);
4920 }
4921
4922 /* update qgroup status and info */
4923 err = btrfs_run_qgroups(trans, fs_info);
4924 if (err < 0)
4925 btrfs_handle_fs_error(fs_info, err,
4926 "failed to update qgroup status and info");
4927 err = btrfs_end_transaction(trans);
4928 if (err && !ret)
4929 ret = err;
4930
4931out:
4932 kfree(sa);
4933drop_write:
4934 mnt_drop_write_file(file);
4935 return ret;
4936}
4937
4938static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4939{
4940 struct inode *inode = file_inode(file);
4941 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4942 struct btrfs_root *root = BTRFS_I(inode)->root;
4943 struct btrfs_ioctl_qgroup_create_args *sa;
4944 struct btrfs_trans_handle *trans;
4945 int ret;
4946 int err;
4947
4948 if (!capable(CAP_SYS_ADMIN))
4949 return -EPERM;
4950
4951 ret = mnt_want_write_file(file);
4952 if (ret)
4953 return ret;
4954
4955 sa = memdup_user(arg, sizeof(*sa));
4956 if (IS_ERR(sa)) {
4957 ret = PTR_ERR(sa);
4958 goto drop_write;
4959 }
4960
4961 if (!sa->qgroupid) {
4962 ret = -EINVAL;
4963 goto out;
4964 }
4965
4966 trans = btrfs_join_transaction(root);
4967 if (IS_ERR(trans)) {
4968 ret = PTR_ERR(trans);
4969 goto out;
4970 }
4971
4972 /* FIXME: check if the IDs really exist */
4973 if (sa->create) {
4974 ret = btrfs_create_qgroup(trans, fs_info, sa->qgroupid);
4975 } else {
4976 ret = btrfs_remove_qgroup(trans, fs_info, sa->qgroupid);
4977 }
4978
4979 err = btrfs_end_transaction(trans);
4980 if (err && !ret)
4981 ret = err;
4982
4983out:
4984 kfree(sa);
4985drop_write:
4986 mnt_drop_write_file(file);
4987 return ret;
4988}
4989
4990static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4991{
4992 struct inode *inode = file_inode(file);
4993 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4994 struct btrfs_root *root = BTRFS_I(inode)->root;
4995 struct btrfs_ioctl_qgroup_limit_args *sa;
4996 struct btrfs_trans_handle *trans;
4997 int ret;
4998 int err;
4999 u64 qgroupid;
5000
5001 if (!capable(CAP_SYS_ADMIN))
5002 return -EPERM;
5003
5004 ret = mnt_want_write_file(file);
5005 if (ret)
5006 return ret;
5007
5008 sa = memdup_user(arg, sizeof(*sa));
5009 if (IS_ERR(sa)) {
5010 ret = PTR_ERR(sa);
5011 goto drop_write;
5012 }
5013
5014 trans = btrfs_join_transaction(root);
5015 if (IS_ERR(trans)) {
5016 ret = PTR_ERR(trans);
5017 goto out;
5018 }
5019
5020 qgroupid = sa->qgroupid;
5021 if (!qgroupid) {
5022 /* take the current subvol as qgroup */
5023 qgroupid = root->root_key.objectid;
5024 }
5025
5026 /* FIXME: check if the IDs really exist */
5027 ret = btrfs_limit_qgroup(trans, fs_info, qgroupid, &sa->lim);
5028
5029 err = btrfs_end_transaction(trans);
5030 if (err && !ret)
5031 ret = err;
5032
5033out:
5034 kfree(sa);
5035drop_write:
5036 mnt_drop_write_file(file);
5037 return ret;
5038}
5039
5040static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
5041{
5042 struct inode *inode = file_inode(file);
5043 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5044 struct btrfs_ioctl_quota_rescan_args *qsa;
5045 int ret;
5046
5047 if (!capable(CAP_SYS_ADMIN))
5048 return -EPERM;
5049
5050 ret = mnt_want_write_file(file);
5051 if (ret)
5052 return ret;
5053
5054 qsa = memdup_user(arg, sizeof(*qsa));
5055 if (IS_ERR(qsa)) {
5056 ret = PTR_ERR(qsa);
5057 goto drop_write;
5058 }
5059
5060 if (qsa->flags) {
5061 ret = -EINVAL;
5062 goto out;
5063 }
5064
5065 ret = btrfs_qgroup_rescan(fs_info);
5066
5067out:
5068 kfree(qsa);
5069drop_write:
5070 mnt_drop_write_file(file);
5071 return ret;
5072}
5073
5074static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
5075{
5076 struct inode *inode = file_inode(file);
5077 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5078 struct btrfs_ioctl_quota_rescan_args *qsa;
5079 int ret = 0;
5080
5081 if (!capable(CAP_SYS_ADMIN))
5082 return -EPERM;
5083
5084 qsa = kzalloc(sizeof(*qsa), GFP_KERNEL);
5085 if (!qsa)
5086 return -ENOMEM;
5087
5088 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
5089 qsa->flags = 1;
5090 qsa->progress = fs_info->qgroup_rescan_progress.objectid;
5091 }
5092
5093 if (copy_to_user(arg, qsa, sizeof(*qsa)))
5094 ret = -EFAULT;
5095
5096 kfree(qsa);
5097 return ret;
5098}
5099
5100static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
5101{
5102 struct inode *inode = file_inode(file);
5103 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5104
5105 if (!capable(CAP_SYS_ADMIN))
5106 return -EPERM;
5107
5108 return btrfs_qgroup_wait_for_completion(fs_info, true);
5109}
5110
5111static long _btrfs_ioctl_set_received_subvol(struct file *file,
5112 struct btrfs_ioctl_received_subvol_args *sa)
5113{
5114 struct inode *inode = file_inode(file);
5115 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5116 struct btrfs_root *root = BTRFS_I(inode)->root;
5117 struct btrfs_root_item *root_item = &root->root_item;
5118 struct btrfs_trans_handle *trans;
5119 struct timespec ct = current_time(inode);
5120 int ret = 0;
5121 int received_uuid_changed;
5122
5123 if (!inode_owner_or_capable(inode))
5124 return -EPERM;
5125
5126 ret = mnt_want_write_file(file);
5127 if (ret < 0)
5128 return ret;
5129
5130 down_write(&fs_info->subvol_sem);
5131
5132 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
5133 ret = -EINVAL;
5134 goto out;
5135 }
5136
5137 if (btrfs_root_readonly(root)) {
5138 ret = -EROFS;
5139 goto out;
5140 }
5141
5142 /*
5143 * 1 - root item
5144 * 2 - uuid items (received uuid + subvol uuid)
5145 */
5146 trans = btrfs_start_transaction(root, 3);
5147 if (IS_ERR(trans)) {
5148 ret = PTR_ERR(trans);
5149 trans = NULL;
5150 goto out;
5151 }
5152
5153 sa->rtransid = trans->transid;
5154 sa->rtime.sec = ct.tv_sec;
5155 sa->rtime.nsec = ct.tv_nsec;
5156
5157 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
5158 BTRFS_UUID_SIZE);
5159 if (received_uuid_changed &&
5160 !btrfs_is_empty_uuid(root_item->received_uuid))
5161 btrfs_uuid_tree_rem(trans, fs_info, root_item->received_uuid,
5162 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5163 root->root_key.objectid);
5164 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
5165 btrfs_set_root_stransid(root_item, sa->stransid);
5166 btrfs_set_root_rtransid(root_item, sa->rtransid);
5167 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
5168 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
5169 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
5170 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
5171
5172 ret = btrfs_update_root(trans, fs_info->tree_root,
5173 &root->root_key, &root->root_item);
5174 if (ret < 0) {
5175 btrfs_end_transaction(trans);
5176 goto out;
5177 }
5178 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
5179 ret = btrfs_uuid_tree_add(trans, fs_info, sa->uuid,
5180 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5181 root->root_key.objectid);
5182 if (ret < 0 && ret != -EEXIST) {
5183 btrfs_abort_transaction(trans, ret);
5184 goto out;
5185 }
5186 }
5187 ret = btrfs_commit_transaction(trans);
5188 if (ret < 0) {
5189 btrfs_abort_transaction(trans, ret);
5190 goto out;
5191 }
5192
5193out:
5194 up_write(&fs_info->subvol_sem);
5195 mnt_drop_write_file(file);
5196 return ret;
5197}
5198
5199#ifdef CONFIG_64BIT
5200static long btrfs_ioctl_set_received_subvol_32(struct file *file,
5201 void __user *arg)
5202{
5203 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
5204 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
5205 int ret = 0;
5206
5207 args32 = memdup_user(arg, sizeof(*args32));
5208 if (IS_ERR(args32))
5209 return PTR_ERR(args32);
5210
5211 args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
5212 if (!args64) {
5213 ret = -ENOMEM;
5214 goto out;
5215 }
5216
5217 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
5218 args64->stransid = args32->stransid;
5219 args64->rtransid = args32->rtransid;
5220 args64->stime.sec = args32->stime.sec;
5221 args64->stime.nsec = args32->stime.nsec;
5222 args64->rtime.sec = args32->rtime.sec;
5223 args64->rtime.nsec = args32->rtime.nsec;
5224 args64->flags = args32->flags;
5225
5226 ret = _btrfs_ioctl_set_received_subvol(file, args64);
5227 if (ret)
5228 goto out;
5229
5230 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
5231 args32->stransid = args64->stransid;
5232 args32->rtransid = args64->rtransid;
5233 args32->stime.sec = args64->stime.sec;
5234 args32->stime.nsec = args64->stime.nsec;
5235 args32->rtime.sec = args64->rtime.sec;
5236 args32->rtime.nsec = args64->rtime.nsec;
5237 args32->flags = args64->flags;
5238
5239 ret = copy_to_user(arg, args32, sizeof(*args32));
5240 if (ret)
5241 ret = -EFAULT;
5242
5243out:
5244 kfree(args32);
5245 kfree(args64);
5246 return ret;
5247}
5248#endif
5249
5250static long btrfs_ioctl_set_received_subvol(struct file *file,
5251 void __user *arg)
5252{
5253 struct btrfs_ioctl_received_subvol_args *sa = NULL;
5254 int ret = 0;
5255
5256 sa = memdup_user(arg, sizeof(*sa));
5257 if (IS_ERR(sa))
5258 return PTR_ERR(sa);
5259
5260 ret = _btrfs_ioctl_set_received_subvol(file, sa);
5261
5262 if (ret)
5263 goto out;
5264
5265 ret = copy_to_user(arg, sa, sizeof(*sa));
5266 if (ret)
5267 ret = -EFAULT;
5268
5269out:
5270 kfree(sa);
5271 return ret;
5272}
5273
5274static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
5275{
5276 struct inode *inode = file_inode(file);
5277 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5278 size_t len;
5279 int ret;
5280 char label[BTRFS_LABEL_SIZE];
5281
5282 spin_lock(&fs_info->super_lock);
5283 memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5284 spin_unlock(&fs_info->super_lock);
5285
5286 len = strnlen(label, BTRFS_LABEL_SIZE);
5287
5288 if (len == BTRFS_LABEL_SIZE) {
5289 btrfs_warn(fs_info,
5290 "label is too long, return the first %zu bytes",
5291 --len);
5292 }
5293
5294 ret = copy_to_user(arg, label, len);
5295
5296 return ret ? -EFAULT : 0;
5297}
5298
5299static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5300{
5301 struct inode *inode = file_inode(file);
5302 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5303 struct btrfs_root *root = BTRFS_I(inode)->root;
5304 struct btrfs_super_block *super_block = fs_info->super_copy;
5305 struct btrfs_trans_handle *trans;
5306 char label[BTRFS_LABEL_SIZE];
5307 int ret;
5308
5309 if (!capable(CAP_SYS_ADMIN))
5310 return -EPERM;
5311
5312 if (copy_from_user(label, arg, sizeof(label)))
5313 return -EFAULT;
5314
5315 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5316 btrfs_err(fs_info,
5317 "unable to set label with more than %d bytes",
5318 BTRFS_LABEL_SIZE - 1);
5319 return -EINVAL;
5320 }
5321
5322 ret = mnt_want_write_file(file);
5323 if (ret)
5324 return ret;
5325
5326 trans = btrfs_start_transaction(root, 0);
5327 if (IS_ERR(trans)) {
5328 ret = PTR_ERR(trans);
5329 goto out_unlock;
5330 }
5331
5332 spin_lock(&fs_info->super_lock);
5333 strcpy(super_block->label, label);
5334 spin_unlock(&fs_info->super_lock);
5335 ret = btrfs_commit_transaction(trans);
5336
5337out_unlock:
5338 mnt_drop_write_file(file);
5339 return ret;
5340}
5341
5342#define INIT_FEATURE_FLAGS(suffix) \
5343 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5344 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5345 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5346
5347int btrfs_ioctl_get_supported_features(void __user *arg)
5348{
5349 static const struct btrfs_ioctl_feature_flags features[3] = {
5350 INIT_FEATURE_FLAGS(SUPP),
5351 INIT_FEATURE_FLAGS(SAFE_SET),
5352 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5353 };
5354
5355 if (copy_to_user(arg, &features, sizeof(features)))
5356 return -EFAULT;
5357
5358 return 0;
5359}
5360
5361static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5362{
5363 struct inode *inode = file_inode(file);
5364 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5365 struct btrfs_super_block *super_block = fs_info->super_copy;
5366 struct btrfs_ioctl_feature_flags features;
5367
5368 features.compat_flags = btrfs_super_compat_flags(super_block);
5369 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5370 features.incompat_flags = btrfs_super_incompat_flags(super_block);
5371
5372 if (copy_to_user(arg, &features, sizeof(features)))
5373 return -EFAULT;
5374
5375 return 0;
5376}
5377
5378static int check_feature_bits(struct btrfs_fs_info *fs_info,
5379 enum btrfs_feature_set set,
5380 u64 change_mask, u64 flags, u64 supported_flags,
5381 u64 safe_set, u64 safe_clear)
5382{
5383 const char *type = btrfs_feature_set_names[set];
5384 char *names;
5385 u64 disallowed, unsupported;
5386 u64 set_mask = flags & change_mask;
5387 u64 clear_mask = ~flags & change_mask;
5388
5389 unsupported = set_mask & ~supported_flags;
5390 if (unsupported) {
5391 names = btrfs_printable_features(set, unsupported);
5392 if (names) {
5393 btrfs_warn(fs_info,
5394 "this kernel does not support the %s feature bit%s",
5395 names, strchr(names, ',') ? "s" : "");
5396 kfree(names);
5397 } else
5398 btrfs_warn(fs_info,
5399 "this kernel does not support %s bits 0x%llx",
5400 type, unsupported);
5401 return -EOPNOTSUPP;
5402 }
5403
5404 disallowed = set_mask & ~safe_set;
5405 if (disallowed) {
5406 names = btrfs_printable_features(set, disallowed);
5407 if (names) {
5408 btrfs_warn(fs_info,
5409 "can't set the %s feature bit%s while mounted",
5410 names, strchr(names, ',') ? "s" : "");
5411 kfree(names);
5412 } else
5413 btrfs_warn(fs_info,
5414 "can't set %s bits 0x%llx while mounted",
5415 type, disallowed);
5416 return -EPERM;
5417 }
5418
5419 disallowed = clear_mask & ~safe_clear;
5420 if (disallowed) {
5421 names = btrfs_printable_features(set, disallowed);
5422 if (names) {
5423 btrfs_warn(fs_info,
5424 "can't clear the %s feature bit%s while mounted",
5425 names, strchr(names, ',') ? "s" : "");
5426 kfree(names);
5427 } else
5428 btrfs_warn(fs_info,
5429 "can't clear %s bits 0x%llx while mounted",
5430 type, disallowed);
5431 return -EPERM;
5432 }
5433
5434 return 0;
5435}
5436
5437#define check_feature(fs_info, change_mask, flags, mask_base) \
5438check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags, \
5439 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
5440 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
5441 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5442
5443static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5444{
5445 struct inode *inode = file_inode(file);
5446 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5447 struct btrfs_root *root = BTRFS_I(inode)->root;
5448 struct btrfs_super_block *super_block = fs_info->super_copy;
5449 struct btrfs_ioctl_feature_flags flags[2];
5450 struct btrfs_trans_handle *trans;
5451 u64 newflags;
5452 int ret;
5453
5454 if (!capable(CAP_SYS_ADMIN))
5455 return -EPERM;
5456
5457 if (copy_from_user(flags, arg, sizeof(flags)))
5458 return -EFAULT;
5459
5460 /* Nothing to do */
5461 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5462 !flags[0].incompat_flags)
5463 return 0;
5464
5465 ret = check_feature(fs_info, flags[0].compat_flags,
5466 flags[1].compat_flags, COMPAT);
5467 if (ret)
5468 return ret;
5469
5470 ret = check_feature(fs_info, flags[0].compat_ro_flags,
5471 flags[1].compat_ro_flags, COMPAT_RO);
5472 if (ret)
5473 return ret;
5474
5475 ret = check_feature(fs_info, flags[0].incompat_flags,
5476 flags[1].incompat_flags, INCOMPAT);
5477 if (ret)
5478 return ret;
5479
5480 ret = mnt_want_write_file(file);
5481 if (ret)
5482 return ret;
5483
5484 trans = btrfs_start_transaction(root, 0);
5485 if (IS_ERR(trans)) {
5486 ret = PTR_ERR(trans);
5487 goto out_drop_write;
5488 }
5489
5490 spin_lock(&fs_info->super_lock);
5491 newflags = btrfs_super_compat_flags(super_block);
5492 newflags |= flags[0].compat_flags & flags[1].compat_flags;
5493 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5494 btrfs_set_super_compat_flags(super_block, newflags);
5495
5496 newflags = btrfs_super_compat_ro_flags(super_block);
5497 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5498 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5499 btrfs_set_super_compat_ro_flags(super_block, newflags);
5500
5501 newflags = btrfs_super_incompat_flags(super_block);
5502 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5503 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5504 btrfs_set_super_incompat_flags(super_block, newflags);
5505 spin_unlock(&fs_info->super_lock);
5506
5507 ret = btrfs_commit_transaction(trans);
5508out_drop_write:
5509 mnt_drop_write_file(file);
5510
5511 return ret;
5512}
5513
5514long btrfs_ioctl(struct file *file, unsigned int
5515 cmd, unsigned long arg)
5516{
5517 struct inode *inode = file_inode(file);
5518 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5519 struct btrfs_root *root = BTRFS_I(inode)->root;
5520 void __user *argp = (void __user *)arg;
5521
5522 switch (cmd) {
5523 case FS_IOC_GETFLAGS:
5524 return btrfs_ioctl_getflags(file, argp);
5525 case FS_IOC_SETFLAGS:
5526 return btrfs_ioctl_setflags(file, argp);
5527 case FS_IOC_GETVERSION:
5528 return btrfs_ioctl_getversion(file, argp);
5529 case FITRIM:
5530 return btrfs_ioctl_fitrim(file, argp);
5531 case BTRFS_IOC_SNAP_CREATE:
5532 return btrfs_ioctl_snap_create(file, argp, 0);
5533 case BTRFS_IOC_SNAP_CREATE_V2:
5534 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5535 case BTRFS_IOC_SUBVOL_CREATE:
5536 return btrfs_ioctl_snap_create(file, argp, 1);
5537 case BTRFS_IOC_SUBVOL_CREATE_V2:
5538 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5539 case BTRFS_IOC_SNAP_DESTROY:
5540 return btrfs_ioctl_snap_destroy(file, argp);
5541 case BTRFS_IOC_SUBVOL_GETFLAGS:
5542 return btrfs_ioctl_subvol_getflags(file, argp);
5543 case BTRFS_IOC_SUBVOL_SETFLAGS:
5544 return btrfs_ioctl_subvol_setflags(file, argp);
5545 case BTRFS_IOC_DEFAULT_SUBVOL:
5546 return btrfs_ioctl_default_subvol(file, argp);
5547 case BTRFS_IOC_DEFRAG:
5548 return btrfs_ioctl_defrag(file, NULL);
5549 case BTRFS_IOC_DEFRAG_RANGE:
5550 return btrfs_ioctl_defrag(file, argp);
5551 case BTRFS_IOC_RESIZE:
5552 return btrfs_ioctl_resize(file, argp);
5553 case BTRFS_IOC_ADD_DEV:
5554 return btrfs_ioctl_add_dev(fs_info, argp);
5555 case BTRFS_IOC_RM_DEV:
5556 return btrfs_ioctl_rm_dev(file, argp);
5557 case BTRFS_IOC_RM_DEV_V2:
5558 return btrfs_ioctl_rm_dev_v2(file, argp);
5559 case BTRFS_IOC_FS_INFO:
5560 return btrfs_ioctl_fs_info(fs_info, argp);
5561 case BTRFS_IOC_DEV_INFO:
5562 return btrfs_ioctl_dev_info(fs_info, argp);
5563 case BTRFS_IOC_BALANCE:
5564 return btrfs_ioctl_balance(file, NULL);
5565 case BTRFS_IOC_TRANS_START:
5566 return btrfs_ioctl_trans_start(file);
5567 case BTRFS_IOC_TRANS_END:
5568 return btrfs_ioctl_trans_end(file);
5569 case BTRFS_IOC_TREE_SEARCH:
5570 return btrfs_ioctl_tree_search(file, argp);
5571 case BTRFS_IOC_TREE_SEARCH_V2:
5572 return btrfs_ioctl_tree_search_v2(file, argp);
5573 case BTRFS_IOC_INO_LOOKUP:
5574 return btrfs_ioctl_ino_lookup(file, argp);
5575 case BTRFS_IOC_INO_PATHS:
5576 return btrfs_ioctl_ino_to_path(root, argp);
5577 case BTRFS_IOC_LOGICAL_INO:
5578 return btrfs_ioctl_logical_to_ino(fs_info, argp);
5579 case BTRFS_IOC_SPACE_INFO:
5580 return btrfs_ioctl_space_info(fs_info, argp);
5581 case BTRFS_IOC_SYNC: {
5582 int ret;
5583
5584 ret = btrfs_start_delalloc_roots(fs_info, 0, -1);
5585 if (ret)
5586 return ret;
5587 ret = btrfs_sync_fs(inode->i_sb, 1);
5588 /*
5589 * The transaction thread may want to do more work,
5590 * namely it pokes the cleaner kthread that will start
5591 * processing uncleaned subvols.
5592 */
5593 wake_up_process(fs_info->transaction_kthread);
5594 return ret;
5595 }
5596 case BTRFS_IOC_START_SYNC:
5597 return btrfs_ioctl_start_sync(root, argp);
5598 case BTRFS_IOC_WAIT_SYNC:
5599 return btrfs_ioctl_wait_sync(fs_info, argp);
5600 case BTRFS_IOC_SCRUB:
5601 return btrfs_ioctl_scrub(file, argp);
5602 case BTRFS_IOC_SCRUB_CANCEL:
5603 return btrfs_ioctl_scrub_cancel(fs_info);
5604 case BTRFS_IOC_SCRUB_PROGRESS:
5605 return btrfs_ioctl_scrub_progress(fs_info, argp);
5606 case BTRFS_IOC_BALANCE_V2:
5607 return btrfs_ioctl_balance(file, argp);
5608 case BTRFS_IOC_BALANCE_CTL:
5609 return btrfs_ioctl_balance_ctl(fs_info, arg);
5610 case BTRFS_IOC_BALANCE_PROGRESS:
5611 return btrfs_ioctl_balance_progress(fs_info, argp);
5612 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5613 return btrfs_ioctl_set_received_subvol(file, argp);
5614#ifdef CONFIG_64BIT
5615 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5616 return btrfs_ioctl_set_received_subvol_32(file, argp);
5617#endif
5618 case BTRFS_IOC_SEND:
5619 return btrfs_ioctl_send(file, argp);
5620 case BTRFS_IOC_GET_DEV_STATS:
5621 return btrfs_ioctl_get_dev_stats(fs_info, argp);
5622 case BTRFS_IOC_QUOTA_CTL:
5623 return btrfs_ioctl_quota_ctl(file, argp);
5624 case BTRFS_IOC_QGROUP_ASSIGN:
5625 return btrfs_ioctl_qgroup_assign(file, argp);
5626 case BTRFS_IOC_QGROUP_CREATE:
5627 return btrfs_ioctl_qgroup_create(file, argp);
5628 case BTRFS_IOC_QGROUP_LIMIT:
5629 return btrfs_ioctl_qgroup_limit(file, argp);
5630 case BTRFS_IOC_QUOTA_RESCAN:
5631 return btrfs_ioctl_quota_rescan(file, argp);
5632 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5633 return btrfs_ioctl_quota_rescan_status(file, argp);
5634 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5635 return btrfs_ioctl_quota_rescan_wait(file, argp);
5636 case BTRFS_IOC_DEV_REPLACE:
5637 return btrfs_ioctl_dev_replace(fs_info, argp);
5638 case BTRFS_IOC_GET_FSLABEL:
5639 return btrfs_ioctl_get_fslabel(file, argp);
5640 case BTRFS_IOC_SET_FSLABEL:
5641 return btrfs_ioctl_set_fslabel(file, argp);
5642 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5643 return btrfs_ioctl_get_supported_features(argp);
5644 case BTRFS_IOC_GET_FEATURES:
5645 return btrfs_ioctl_get_features(file, argp);
5646 case BTRFS_IOC_SET_FEATURES:
5647 return btrfs_ioctl_set_features(file, argp);
5648 }
5649
5650 return -ENOTTY;
5651}
5652
5653#ifdef CONFIG_COMPAT
5654long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
5655{
5656 /*
5657 * These all access 32-bit values anyway so no further
5658 * handling is necessary.
5659 */
5660 switch (cmd) {
5661 case FS_IOC32_GETFLAGS:
5662 cmd = FS_IOC_GETFLAGS;
5663 break;
5664 case FS_IOC32_SETFLAGS:
5665 cmd = FS_IOC_SETFLAGS;
5666 break;
5667 case FS_IOC32_GETVERSION:
5668 cmd = FS_IOC_GETVERSION;
5669 break;
5670 }
5671
5672 return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
5673}
5674#endif