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1/*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19#include <linux/kernel.h>
20#include <linux/bio.h>
21#include <linux/buffer_head.h>
22#include <linux/file.h>
23#include <linux/fs.h>
24#include <linux/fsnotify.h>
25#include <linux/pagemap.h>
26#include <linux/highmem.h>
27#include <linux/time.h>
28#include <linux/init.h>
29#include <linux/string.h>
30#include <linux/backing-dev.h>
31#include <linux/mount.h>
32#include <linux/mpage.h>
33#include <linux/namei.h>
34#include <linux/swap.h>
35#include <linux/writeback.h>
36#include <linux/statfs.h>
37#include <linux/compat.h>
38#include <linux/bit_spinlock.h>
39#include <linux/security.h>
40#include <linux/xattr.h>
41#include <linux/vmalloc.h>
42#include <linux/slab.h>
43#include <linux/blkdev.h>
44#include "compat.h"
45#include "ctree.h"
46#include "disk-io.h"
47#include "transaction.h"
48#include "btrfs_inode.h"
49#include "ioctl.h"
50#include "print-tree.h"
51#include "volumes.h"
52#include "locking.h"
53#include "inode-map.h"
54
55/* Mask out flags that are inappropriate for the given type of inode. */
56static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
57{
58 if (S_ISDIR(mode))
59 return flags;
60 else if (S_ISREG(mode))
61 return flags & ~FS_DIRSYNC_FL;
62 else
63 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
64}
65
66/*
67 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
68 */
69static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
70{
71 unsigned int iflags = 0;
72
73 if (flags & BTRFS_INODE_SYNC)
74 iflags |= FS_SYNC_FL;
75 if (flags & BTRFS_INODE_IMMUTABLE)
76 iflags |= FS_IMMUTABLE_FL;
77 if (flags & BTRFS_INODE_APPEND)
78 iflags |= FS_APPEND_FL;
79 if (flags & BTRFS_INODE_NODUMP)
80 iflags |= FS_NODUMP_FL;
81 if (flags & BTRFS_INODE_NOATIME)
82 iflags |= FS_NOATIME_FL;
83 if (flags & BTRFS_INODE_DIRSYNC)
84 iflags |= FS_DIRSYNC_FL;
85 if (flags & BTRFS_INODE_NODATACOW)
86 iflags |= FS_NOCOW_FL;
87
88 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
89 iflags |= FS_COMPR_FL;
90 else if (flags & BTRFS_INODE_NOCOMPRESS)
91 iflags |= FS_NOCOMP_FL;
92
93 return iflags;
94}
95
96/*
97 * Update inode->i_flags based on the btrfs internal flags.
98 */
99void btrfs_update_iflags(struct inode *inode)
100{
101 struct btrfs_inode *ip = BTRFS_I(inode);
102
103 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
104
105 if (ip->flags & BTRFS_INODE_SYNC)
106 inode->i_flags |= S_SYNC;
107 if (ip->flags & BTRFS_INODE_IMMUTABLE)
108 inode->i_flags |= S_IMMUTABLE;
109 if (ip->flags & BTRFS_INODE_APPEND)
110 inode->i_flags |= S_APPEND;
111 if (ip->flags & BTRFS_INODE_NOATIME)
112 inode->i_flags |= S_NOATIME;
113 if (ip->flags & BTRFS_INODE_DIRSYNC)
114 inode->i_flags |= S_DIRSYNC;
115}
116
117/*
118 * Inherit flags from the parent inode.
119 *
120 * Unlike extN we don't have any flags we don't want to inherit currently.
121 */
122void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
123{
124 unsigned int flags;
125
126 if (!dir)
127 return;
128
129 flags = BTRFS_I(dir)->flags;
130
131 if (S_ISREG(inode->i_mode))
132 flags &= ~BTRFS_INODE_DIRSYNC;
133 else if (!S_ISDIR(inode->i_mode))
134 flags &= (BTRFS_INODE_NODUMP | BTRFS_INODE_NOATIME);
135
136 BTRFS_I(inode)->flags = flags;
137 btrfs_update_iflags(inode);
138}
139
140static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
141{
142 struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
143 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
144
145 if (copy_to_user(arg, &flags, sizeof(flags)))
146 return -EFAULT;
147 return 0;
148}
149
150static int check_flags(unsigned int flags)
151{
152 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
153 FS_NOATIME_FL | FS_NODUMP_FL | \
154 FS_SYNC_FL | FS_DIRSYNC_FL | \
155 FS_NOCOMP_FL | FS_COMPR_FL |
156 FS_NOCOW_FL))
157 return -EOPNOTSUPP;
158
159 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
160 return -EINVAL;
161
162 return 0;
163}
164
165static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
166{
167 struct inode *inode = file->f_path.dentry->d_inode;
168 struct btrfs_inode *ip = BTRFS_I(inode);
169 struct btrfs_root *root = ip->root;
170 struct btrfs_trans_handle *trans;
171 unsigned int flags, oldflags;
172 int ret;
173
174 if (btrfs_root_readonly(root))
175 return -EROFS;
176
177 if (copy_from_user(&flags, arg, sizeof(flags)))
178 return -EFAULT;
179
180 ret = check_flags(flags);
181 if (ret)
182 return ret;
183
184 if (!inode_owner_or_capable(inode))
185 return -EACCES;
186
187 mutex_lock(&inode->i_mutex);
188
189 flags = btrfs_mask_flags(inode->i_mode, flags);
190 oldflags = btrfs_flags_to_ioctl(ip->flags);
191 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
192 if (!capable(CAP_LINUX_IMMUTABLE)) {
193 ret = -EPERM;
194 goto out_unlock;
195 }
196 }
197
198 ret = mnt_want_write(file->f_path.mnt);
199 if (ret)
200 goto out_unlock;
201
202 if (flags & FS_SYNC_FL)
203 ip->flags |= BTRFS_INODE_SYNC;
204 else
205 ip->flags &= ~BTRFS_INODE_SYNC;
206 if (flags & FS_IMMUTABLE_FL)
207 ip->flags |= BTRFS_INODE_IMMUTABLE;
208 else
209 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
210 if (flags & FS_APPEND_FL)
211 ip->flags |= BTRFS_INODE_APPEND;
212 else
213 ip->flags &= ~BTRFS_INODE_APPEND;
214 if (flags & FS_NODUMP_FL)
215 ip->flags |= BTRFS_INODE_NODUMP;
216 else
217 ip->flags &= ~BTRFS_INODE_NODUMP;
218 if (flags & FS_NOATIME_FL)
219 ip->flags |= BTRFS_INODE_NOATIME;
220 else
221 ip->flags &= ~BTRFS_INODE_NOATIME;
222 if (flags & FS_DIRSYNC_FL)
223 ip->flags |= BTRFS_INODE_DIRSYNC;
224 else
225 ip->flags &= ~BTRFS_INODE_DIRSYNC;
226 if (flags & FS_NOCOW_FL)
227 ip->flags |= BTRFS_INODE_NODATACOW;
228 else
229 ip->flags &= ~BTRFS_INODE_NODATACOW;
230
231 /*
232 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
233 * flag may be changed automatically if compression code won't make
234 * things smaller.
235 */
236 if (flags & FS_NOCOMP_FL) {
237 ip->flags &= ~BTRFS_INODE_COMPRESS;
238 ip->flags |= BTRFS_INODE_NOCOMPRESS;
239 } else if (flags & FS_COMPR_FL) {
240 ip->flags |= BTRFS_INODE_COMPRESS;
241 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
242 } else {
243 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
244 }
245
246 trans = btrfs_join_transaction(root);
247 BUG_ON(IS_ERR(trans));
248
249 ret = btrfs_update_inode(trans, root, inode);
250 BUG_ON(ret);
251
252 btrfs_update_iflags(inode);
253 inode->i_ctime = CURRENT_TIME;
254 btrfs_end_transaction(trans, root);
255
256 mnt_drop_write(file->f_path.mnt);
257
258 ret = 0;
259 out_unlock:
260 mutex_unlock(&inode->i_mutex);
261 return ret;
262}
263
264static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
265{
266 struct inode *inode = file->f_path.dentry->d_inode;
267
268 return put_user(inode->i_generation, arg);
269}
270
271static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
272{
273 struct btrfs_root *root = fdentry(file)->d_sb->s_fs_info;
274 struct btrfs_fs_info *fs_info = root->fs_info;
275 struct btrfs_device *device;
276 struct request_queue *q;
277 struct fstrim_range range;
278 u64 minlen = ULLONG_MAX;
279 u64 num_devices = 0;
280 int ret;
281
282 if (!capable(CAP_SYS_ADMIN))
283 return -EPERM;
284
285 rcu_read_lock();
286 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
287 dev_list) {
288 if (!device->bdev)
289 continue;
290 q = bdev_get_queue(device->bdev);
291 if (blk_queue_discard(q)) {
292 num_devices++;
293 minlen = min((u64)q->limits.discard_granularity,
294 minlen);
295 }
296 }
297 rcu_read_unlock();
298 if (!num_devices)
299 return -EOPNOTSUPP;
300
301 if (copy_from_user(&range, arg, sizeof(range)))
302 return -EFAULT;
303
304 range.minlen = max(range.minlen, minlen);
305 ret = btrfs_trim_fs(root, &range);
306 if (ret < 0)
307 return ret;
308
309 if (copy_to_user(arg, &range, sizeof(range)))
310 return -EFAULT;
311
312 return 0;
313}
314
315static noinline int create_subvol(struct btrfs_root *root,
316 struct dentry *dentry,
317 char *name, int namelen,
318 u64 *async_transid)
319{
320 struct btrfs_trans_handle *trans;
321 struct btrfs_key key;
322 struct btrfs_root_item root_item;
323 struct btrfs_inode_item *inode_item;
324 struct extent_buffer *leaf;
325 struct btrfs_root *new_root;
326 struct dentry *parent = dentry->d_parent;
327 struct inode *dir;
328 int ret;
329 int err;
330 u64 objectid;
331 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
332 u64 index = 0;
333
334 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
335 if (ret)
336 return ret;
337
338 dir = parent->d_inode;
339
340 /*
341 * 1 - inode item
342 * 2 - refs
343 * 1 - root item
344 * 2 - dir items
345 */
346 trans = btrfs_start_transaction(root, 6);
347 if (IS_ERR(trans))
348 return PTR_ERR(trans);
349
350 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
351 0, objectid, NULL, 0, 0, 0);
352 if (IS_ERR(leaf)) {
353 ret = PTR_ERR(leaf);
354 goto fail;
355 }
356
357 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
358 btrfs_set_header_bytenr(leaf, leaf->start);
359 btrfs_set_header_generation(leaf, trans->transid);
360 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
361 btrfs_set_header_owner(leaf, objectid);
362
363 write_extent_buffer(leaf, root->fs_info->fsid,
364 (unsigned long)btrfs_header_fsid(leaf),
365 BTRFS_FSID_SIZE);
366 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
367 (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
368 BTRFS_UUID_SIZE);
369 btrfs_mark_buffer_dirty(leaf);
370
371 inode_item = &root_item.inode;
372 memset(inode_item, 0, sizeof(*inode_item));
373 inode_item->generation = cpu_to_le64(1);
374 inode_item->size = cpu_to_le64(3);
375 inode_item->nlink = cpu_to_le32(1);
376 inode_item->nbytes = cpu_to_le64(root->leafsize);
377 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
378
379 root_item.flags = 0;
380 root_item.byte_limit = 0;
381 inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
382
383 btrfs_set_root_bytenr(&root_item, leaf->start);
384 btrfs_set_root_generation(&root_item, trans->transid);
385 btrfs_set_root_level(&root_item, 0);
386 btrfs_set_root_refs(&root_item, 1);
387 btrfs_set_root_used(&root_item, leaf->len);
388 btrfs_set_root_last_snapshot(&root_item, 0);
389
390 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
391 root_item.drop_level = 0;
392
393 btrfs_tree_unlock(leaf);
394 free_extent_buffer(leaf);
395 leaf = NULL;
396
397 btrfs_set_root_dirid(&root_item, new_dirid);
398
399 key.objectid = objectid;
400 key.offset = 0;
401 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
402 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
403 &root_item);
404 if (ret)
405 goto fail;
406
407 key.offset = (u64)-1;
408 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
409 BUG_ON(IS_ERR(new_root));
410
411 btrfs_record_root_in_trans(trans, new_root);
412
413 ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
414 /*
415 * insert the directory item
416 */
417 ret = btrfs_set_inode_index(dir, &index);
418 BUG_ON(ret);
419
420 ret = btrfs_insert_dir_item(trans, root,
421 name, namelen, dir, &key,
422 BTRFS_FT_DIR, index);
423 if (ret)
424 goto fail;
425
426 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
427 ret = btrfs_update_inode(trans, root, dir);
428 BUG_ON(ret);
429
430 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
431 objectid, root->root_key.objectid,
432 btrfs_ino(dir), index, name, namelen);
433
434 BUG_ON(ret);
435
436 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
437fail:
438 if (async_transid) {
439 *async_transid = trans->transid;
440 err = btrfs_commit_transaction_async(trans, root, 1);
441 } else {
442 err = btrfs_commit_transaction(trans, root);
443 }
444 if (err && !ret)
445 ret = err;
446 return ret;
447}
448
449static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
450 char *name, int namelen, u64 *async_transid,
451 bool readonly)
452{
453 struct inode *inode;
454 struct btrfs_pending_snapshot *pending_snapshot;
455 struct btrfs_trans_handle *trans;
456 int ret;
457
458 if (!root->ref_cows)
459 return -EINVAL;
460
461 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
462 if (!pending_snapshot)
463 return -ENOMEM;
464
465 btrfs_init_block_rsv(&pending_snapshot->block_rsv);
466 pending_snapshot->dentry = dentry;
467 pending_snapshot->root = root;
468 pending_snapshot->readonly = readonly;
469
470 trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
471 if (IS_ERR(trans)) {
472 ret = PTR_ERR(trans);
473 goto fail;
474 }
475
476 ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
477 BUG_ON(ret);
478
479 spin_lock(&root->fs_info->trans_lock);
480 list_add(&pending_snapshot->list,
481 &trans->transaction->pending_snapshots);
482 spin_unlock(&root->fs_info->trans_lock);
483 if (async_transid) {
484 *async_transid = trans->transid;
485 ret = btrfs_commit_transaction_async(trans,
486 root->fs_info->extent_root, 1);
487 } else {
488 ret = btrfs_commit_transaction(trans,
489 root->fs_info->extent_root);
490 }
491 BUG_ON(ret);
492
493 ret = pending_snapshot->error;
494 if (ret)
495 goto fail;
496
497 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
498 if (ret)
499 goto fail;
500
501 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
502 if (IS_ERR(inode)) {
503 ret = PTR_ERR(inode);
504 goto fail;
505 }
506 BUG_ON(!inode);
507 d_instantiate(dentry, inode);
508 ret = 0;
509fail:
510 kfree(pending_snapshot);
511 return ret;
512}
513
514/* copy of check_sticky in fs/namei.c()
515* It's inline, so penalty for filesystems that don't use sticky bit is
516* minimal.
517*/
518static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
519{
520 uid_t fsuid = current_fsuid();
521
522 if (!(dir->i_mode & S_ISVTX))
523 return 0;
524 if (inode->i_uid == fsuid)
525 return 0;
526 if (dir->i_uid == fsuid)
527 return 0;
528 return !capable(CAP_FOWNER);
529}
530
531/* copy of may_delete in fs/namei.c()
532 * Check whether we can remove a link victim from directory dir, check
533 * whether the type of victim is right.
534 * 1. We can't do it if dir is read-only (done in permission())
535 * 2. We should have write and exec permissions on dir
536 * 3. We can't remove anything from append-only dir
537 * 4. We can't do anything with immutable dir (done in permission())
538 * 5. If the sticky bit on dir is set we should either
539 * a. be owner of dir, or
540 * b. be owner of victim, or
541 * c. have CAP_FOWNER capability
542 * 6. If the victim is append-only or immutable we can't do antyhing with
543 * links pointing to it.
544 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
545 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
546 * 9. We can't remove a root or mountpoint.
547 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
548 * nfs_async_unlink().
549 */
550
551static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
552{
553 int error;
554
555 if (!victim->d_inode)
556 return -ENOENT;
557
558 BUG_ON(victim->d_parent->d_inode != dir);
559 audit_inode_child(victim, dir);
560
561 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
562 if (error)
563 return error;
564 if (IS_APPEND(dir))
565 return -EPERM;
566 if (btrfs_check_sticky(dir, victim->d_inode)||
567 IS_APPEND(victim->d_inode)||
568 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
569 return -EPERM;
570 if (isdir) {
571 if (!S_ISDIR(victim->d_inode->i_mode))
572 return -ENOTDIR;
573 if (IS_ROOT(victim))
574 return -EBUSY;
575 } else if (S_ISDIR(victim->d_inode->i_mode))
576 return -EISDIR;
577 if (IS_DEADDIR(dir))
578 return -ENOENT;
579 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
580 return -EBUSY;
581 return 0;
582}
583
584/* copy of may_create in fs/namei.c() */
585static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
586{
587 if (child->d_inode)
588 return -EEXIST;
589 if (IS_DEADDIR(dir))
590 return -ENOENT;
591 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
592}
593
594/*
595 * Create a new subvolume below @parent. This is largely modeled after
596 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
597 * inside this filesystem so it's quite a bit simpler.
598 */
599static noinline int btrfs_mksubvol(struct path *parent,
600 char *name, int namelen,
601 struct btrfs_root *snap_src,
602 u64 *async_transid, bool readonly)
603{
604 struct inode *dir = parent->dentry->d_inode;
605 struct dentry *dentry;
606 int error;
607
608 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
609
610 dentry = lookup_one_len(name, parent->dentry, namelen);
611 error = PTR_ERR(dentry);
612 if (IS_ERR(dentry))
613 goto out_unlock;
614
615 error = -EEXIST;
616 if (dentry->d_inode)
617 goto out_dput;
618
619 error = mnt_want_write(parent->mnt);
620 if (error)
621 goto out_dput;
622
623 error = btrfs_may_create(dir, dentry);
624 if (error)
625 goto out_drop_write;
626
627 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
628
629 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
630 goto out_up_read;
631
632 if (snap_src) {
633 error = create_snapshot(snap_src, dentry,
634 name, namelen, async_transid, readonly);
635 } else {
636 error = create_subvol(BTRFS_I(dir)->root, dentry,
637 name, namelen, async_transid);
638 }
639 if (!error)
640 fsnotify_mkdir(dir, dentry);
641out_up_read:
642 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
643out_drop_write:
644 mnt_drop_write(parent->mnt);
645out_dput:
646 dput(dentry);
647out_unlock:
648 mutex_unlock(&dir->i_mutex);
649 return error;
650}
651
652/*
653 * When we're defragging a range, we don't want to kick it off again
654 * if it is really just waiting for delalloc to send it down.
655 * If we find a nice big extent or delalloc range for the bytes in the
656 * file you want to defrag, we return 0 to let you know to skip this
657 * part of the file
658 */
659static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
660{
661 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
662 struct extent_map *em = NULL;
663 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
664 u64 end;
665
666 read_lock(&em_tree->lock);
667 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
668 read_unlock(&em_tree->lock);
669
670 if (em) {
671 end = extent_map_end(em);
672 free_extent_map(em);
673 if (end - offset > thresh)
674 return 0;
675 }
676 /* if we already have a nice delalloc here, just stop */
677 thresh /= 2;
678 end = count_range_bits(io_tree, &offset, offset + thresh,
679 thresh, EXTENT_DELALLOC, 1);
680 if (end >= thresh)
681 return 0;
682 return 1;
683}
684
685/*
686 * helper function to walk through a file and find extents
687 * newer than a specific transid, and smaller than thresh.
688 *
689 * This is used by the defragging code to find new and small
690 * extents
691 */
692static int find_new_extents(struct btrfs_root *root,
693 struct inode *inode, u64 newer_than,
694 u64 *off, int thresh)
695{
696 struct btrfs_path *path;
697 struct btrfs_key min_key;
698 struct btrfs_key max_key;
699 struct extent_buffer *leaf;
700 struct btrfs_file_extent_item *extent;
701 int type;
702 int ret;
703 u64 ino = btrfs_ino(inode);
704
705 path = btrfs_alloc_path();
706 if (!path)
707 return -ENOMEM;
708
709 min_key.objectid = ino;
710 min_key.type = BTRFS_EXTENT_DATA_KEY;
711 min_key.offset = *off;
712
713 max_key.objectid = ino;
714 max_key.type = (u8)-1;
715 max_key.offset = (u64)-1;
716
717 path->keep_locks = 1;
718
719 while(1) {
720 ret = btrfs_search_forward(root, &min_key, &max_key,
721 path, 0, newer_than);
722 if (ret != 0)
723 goto none;
724 if (min_key.objectid != ino)
725 goto none;
726 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
727 goto none;
728
729 leaf = path->nodes[0];
730 extent = btrfs_item_ptr(leaf, path->slots[0],
731 struct btrfs_file_extent_item);
732
733 type = btrfs_file_extent_type(leaf, extent);
734 if (type == BTRFS_FILE_EXTENT_REG &&
735 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
736 check_defrag_in_cache(inode, min_key.offset, thresh)) {
737 *off = min_key.offset;
738 btrfs_free_path(path);
739 return 0;
740 }
741
742 if (min_key.offset == (u64)-1)
743 goto none;
744
745 min_key.offset++;
746 btrfs_release_path(path);
747 }
748none:
749 btrfs_free_path(path);
750 return -ENOENT;
751}
752
753static int should_defrag_range(struct inode *inode, u64 start, u64 len,
754 int thresh, u64 *last_len, u64 *skip,
755 u64 *defrag_end)
756{
757 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
758 struct extent_map *em = NULL;
759 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
760 int ret = 1;
761
762 /*
763 * make sure that once we start defragging and extent, we keep on
764 * defragging it
765 */
766 if (start < *defrag_end)
767 return 1;
768
769 *skip = 0;
770
771 /*
772 * hopefully we have this extent in the tree already, try without
773 * the full extent lock
774 */
775 read_lock(&em_tree->lock);
776 em = lookup_extent_mapping(em_tree, start, len);
777 read_unlock(&em_tree->lock);
778
779 if (!em) {
780 /* get the big lock and read metadata off disk */
781 lock_extent(io_tree, start, start + len - 1, GFP_NOFS);
782 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
783 unlock_extent(io_tree, start, start + len - 1, GFP_NOFS);
784
785 if (IS_ERR(em))
786 return 0;
787 }
788
789 /* this will cover holes, and inline extents */
790 if (em->block_start >= EXTENT_MAP_LAST_BYTE)
791 ret = 0;
792
793 /*
794 * we hit a real extent, if it is big don't bother defragging it again
795 */
796 if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
797 ret = 0;
798
799 /*
800 * last_len ends up being a counter of how many bytes we've defragged.
801 * every time we choose not to defrag an extent, we reset *last_len
802 * so that the next tiny extent will force a defrag.
803 *
804 * The end result of this is that tiny extents before a single big
805 * extent will force at least part of that big extent to be defragged.
806 */
807 if (ret) {
808 *last_len += len;
809 *defrag_end = extent_map_end(em);
810 } else {
811 *last_len = 0;
812 *skip = extent_map_end(em);
813 *defrag_end = 0;
814 }
815
816 free_extent_map(em);
817 return ret;
818}
819
820/*
821 * it doesn't do much good to defrag one or two pages
822 * at a time. This pulls in a nice chunk of pages
823 * to COW and defrag.
824 *
825 * It also makes sure the delalloc code has enough
826 * dirty data to avoid making new small extents as part
827 * of the defrag
828 *
829 * It's a good idea to start RA on this range
830 * before calling this.
831 */
832static int cluster_pages_for_defrag(struct inode *inode,
833 struct page **pages,
834 unsigned long start_index,
835 int num_pages)
836{
837 unsigned long file_end;
838 u64 isize = i_size_read(inode);
839 u64 page_start;
840 u64 page_end;
841 int ret;
842 int i;
843 int i_done;
844 struct btrfs_ordered_extent *ordered;
845 struct extent_state *cached_state = NULL;
846
847 if (isize == 0)
848 return 0;
849 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
850
851 ret = btrfs_delalloc_reserve_space(inode,
852 num_pages << PAGE_CACHE_SHIFT);
853 if (ret)
854 return ret;
855again:
856 ret = 0;
857 i_done = 0;
858
859 /* step one, lock all the pages */
860 for (i = 0; i < num_pages; i++) {
861 struct page *page;
862 page = find_or_create_page(inode->i_mapping,
863 start_index + i, GFP_NOFS);
864 if (!page)
865 break;
866
867 if (!PageUptodate(page)) {
868 btrfs_readpage(NULL, page);
869 lock_page(page);
870 if (!PageUptodate(page)) {
871 unlock_page(page);
872 page_cache_release(page);
873 ret = -EIO;
874 break;
875 }
876 }
877 isize = i_size_read(inode);
878 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
879 if (!isize || page->index > file_end ||
880 page->mapping != inode->i_mapping) {
881 /* whoops, we blew past eof, skip this page */
882 unlock_page(page);
883 page_cache_release(page);
884 break;
885 }
886 pages[i] = page;
887 i_done++;
888 }
889 if (!i_done || ret)
890 goto out;
891
892 if (!(inode->i_sb->s_flags & MS_ACTIVE))
893 goto out;
894
895 /*
896 * so now we have a nice long stream of locked
897 * and up to date pages, lets wait on them
898 */
899 for (i = 0; i < i_done; i++)
900 wait_on_page_writeback(pages[i]);
901
902 page_start = page_offset(pages[0]);
903 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
904
905 lock_extent_bits(&BTRFS_I(inode)->io_tree,
906 page_start, page_end - 1, 0, &cached_state,
907 GFP_NOFS);
908 ordered = btrfs_lookup_first_ordered_extent(inode, page_end - 1);
909 if (ordered &&
910 ordered->file_offset + ordered->len > page_start &&
911 ordered->file_offset < page_end) {
912 btrfs_put_ordered_extent(ordered);
913 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
914 page_start, page_end - 1,
915 &cached_state, GFP_NOFS);
916 for (i = 0; i < i_done; i++) {
917 unlock_page(pages[i]);
918 page_cache_release(pages[i]);
919 }
920 btrfs_wait_ordered_range(inode, page_start,
921 page_end - page_start);
922 goto again;
923 }
924 if (ordered)
925 btrfs_put_ordered_extent(ordered);
926
927 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
928 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
929 EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
930 GFP_NOFS);
931
932 if (i_done != num_pages) {
933 spin_lock(&BTRFS_I(inode)->lock);
934 BTRFS_I(inode)->outstanding_extents++;
935 spin_unlock(&BTRFS_I(inode)->lock);
936 btrfs_delalloc_release_space(inode,
937 (num_pages - i_done) << PAGE_CACHE_SHIFT);
938 }
939
940
941 btrfs_set_extent_delalloc(inode, page_start, page_end - 1,
942 &cached_state);
943
944 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
945 page_start, page_end - 1, &cached_state,
946 GFP_NOFS);
947
948 for (i = 0; i < i_done; i++) {
949 clear_page_dirty_for_io(pages[i]);
950 ClearPageChecked(pages[i]);
951 set_page_extent_mapped(pages[i]);
952 set_page_dirty(pages[i]);
953 unlock_page(pages[i]);
954 page_cache_release(pages[i]);
955 }
956 return i_done;
957out:
958 for (i = 0; i < i_done; i++) {
959 unlock_page(pages[i]);
960 page_cache_release(pages[i]);
961 }
962 btrfs_delalloc_release_space(inode, num_pages << PAGE_CACHE_SHIFT);
963 return ret;
964
965}
966
967int btrfs_defrag_file(struct inode *inode, struct file *file,
968 struct btrfs_ioctl_defrag_range_args *range,
969 u64 newer_than, unsigned long max_to_defrag)
970{
971 struct btrfs_root *root = BTRFS_I(inode)->root;
972 struct btrfs_super_block *disk_super;
973 struct file_ra_state *ra = NULL;
974 unsigned long last_index;
975 u64 features;
976 u64 last_len = 0;
977 u64 skip = 0;
978 u64 defrag_end = 0;
979 u64 newer_off = range->start;
980 int newer_left = 0;
981 unsigned long i;
982 int ret;
983 int defrag_count = 0;
984 int compress_type = BTRFS_COMPRESS_ZLIB;
985 int extent_thresh = range->extent_thresh;
986 int newer_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
987 u64 new_align = ~((u64)128 * 1024 - 1);
988 struct page **pages = NULL;
989
990 if (extent_thresh == 0)
991 extent_thresh = 256 * 1024;
992
993 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
994 if (range->compress_type > BTRFS_COMPRESS_TYPES)
995 return -EINVAL;
996 if (range->compress_type)
997 compress_type = range->compress_type;
998 }
999
1000 if (inode->i_size == 0)
1001 return 0;
1002
1003 /*
1004 * if we were not given a file, allocate a readahead
1005 * context
1006 */
1007 if (!file) {
1008 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1009 if (!ra)
1010 return -ENOMEM;
1011 file_ra_state_init(ra, inode->i_mapping);
1012 } else {
1013 ra = &file->f_ra;
1014 }
1015
1016 pages = kmalloc(sizeof(struct page *) * newer_cluster,
1017 GFP_NOFS);
1018 if (!pages) {
1019 ret = -ENOMEM;
1020 goto out_ra;
1021 }
1022
1023 /* find the last page to defrag */
1024 if (range->start + range->len > range->start) {
1025 last_index = min_t(u64, inode->i_size - 1,
1026 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1027 } else {
1028 last_index = (inode->i_size - 1) >> PAGE_CACHE_SHIFT;
1029 }
1030
1031 if (newer_than) {
1032 ret = find_new_extents(root, inode, newer_than,
1033 &newer_off, 64 * 1024);
1034 if (!ret) {
1035 range->start = newer_off;
1036 /*
1037 * we always align our defrag to help keep
1038 * the extents in the file evenly spaced
1039 */
1040 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1041 newer_left = newer_cluster;
1042 } else
1043 goto out_ra;
1044 } else {
1045 i = range->start >> PAGE_CACHE_SHIFT;
1046 }
1047 if (!max_to_defrag)
1048 max_to_defrag = last_index - 1;
1049
1050 /*
1051 * make writeback starts from i, so the defrag range can be
1052 * written sequentially.
1053 */
1054 if (i < inode->i_mapping->writeback_index)
1055 inode->i_mapping->writeback_index = i;
1056
1057 while (i <= last_index && defrag_count < max_to_defrag &&
1058 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1059 PAGE_CACHE_SHIFT)) {
1060 /*
1061 * make sure we stop running if someone unmounts
1062 * the FS
1063 */
1064 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1065 break;
1066
1067 if (!newer_than &&
1068 !should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1069 PAGE_CACHE_SIZE,
1070 extent_thresh,
1071 &last_len, &skip,
1072 &defrag_end)) {
1073 unsigned long next;
1074 /*
1075 * the should_defrag function tells us how much to skip
1076 * bump our counter by the suggested amount
1077 */
1078 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1079 i = max(i + 1, next);
1080 continue;
1081 }
1082 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1083 BTRFS_I(inode)->force_compress = compress_type;
1084
1085 btrfs_force_ra(inode->i_mapping, ra, file, i, newer_cluster);
1086
1087 ret = cluster_pages_for_defrag(inode, pages, i, newer_cluster);
1088 if (ret < 0)
1089 goto out_ra;
1090
1091 defrag_count += ret;
1092 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
1093 i += ret;
1094
1095 if (newer_than) {
1096 if (newer_off == (u64)-1)
1097 break;
1098
1099 newer_off = max(newer_off + 1,
1100 (u64)i << PAGE_CACHE_SHIFT);
1101
1102 ret = find_new_extents(root, inode,
1103 newer_than, &newer_off,
1104 64 * 1024);
1105 if (!ret) {
1106 range->start = newer_off;
1107 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1108 newer_left = newer_cluster;
1109 } else {
1110 break;
1111 }
1112 } else {
1113 i++;
1114 }
1115 }
1116
1117 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1118 filemap_flush(inode->i_mapping);
1119
1120 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1121 /* the filemap_flush will queue IO into the worker threads, but
1122 * we have to make sure the IO is actually started and that
1123 * ordered extents get created before we return
1124 */
1125 atomic_inc(&root->fs_info->async_submit_draining);
1126 while (atomic_read(&root->fs_info->nr_async_submits) ||
1127 atomic_read(&root->fs_info->async_delalloc_pages)) {
1128 wait_event(root->fs_info->async_submit_wait,
1129 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1130 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1131 }
1132 atomic_dec(&root->fs_info->async_submit_draining);
1133
1134 mutex_lock(&inode->i_mutex);
1135 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1136 mutex_unlock(&inode->i_mutex);
1137 }
1138
1139 disk_super = &root->fs_info->super_copy;
1140 features = btrfs_super_incompat_flags(disk_super);
1141 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1142 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
1143 btrfs_set_super_incompat_flags(disk_super, features);
1144 }
1145
1146 if (!file)
1147 kfree(ra);
1148 return defrag_count;
1149
1150out_ra:
1151 if (!file)
1152 kfree(ra);
1153 kfree(pages);
1154 return ret;
1155}
1156
1157static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
1158 void __user *arg)
1159{
1160 u64 new_size;
1161 u64 old_size;
1162 u64 devid = 1;
1163 struct btrfs_ioctl_vol_args *vol_args;
1164 struct btrfs_trans_handle *trans;
1165 struct btrfs_device *device = NULL;
1166 char *sizestr;
1167 char *devstr = NULL;
1168 int ret = 0;
1169 int mod = 0;
1170
1171 if (root->fs_info->sb->s_flags & MS_RDONLY)
1172 return -EROFS;
1173
1174 if (!capable(CAP_SYS_ADMIN))
1175 return -EPERM;
1176
1177 vol_args = memdup_user(arg, sizeof(*vol_args));
1178 if (IS_ERR(vol_args))
1179 return PTR_ERR(vol_args);
1180
1181 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1182
1183 mutex_lock(&root->fs_info->volume_mutex);
1184 sizestr = vol_args->name;
1185 devstr = strchr(sizestr, ':');
1186 if (devstr) {
1187 char *end;
1188 sizestr = devstr + 1;
1189 *devstr = '\0';
1190 devstr = vol_args->name;
1191 devid = simple_strtoull(devstr, &end, 10);
1192 printk(KERN_INFO "resizing devid %llu\n",
1193 (unsigned long long)devid);
1194 }
1195 device = btrfs_find_device(root, devid, NULL, NULL);
1196 if (!device) {
1197 printk(KERN_INFO "resizer unable to find device %llu\n",
1198 (unsigned long long)devid);
1199 ret = -EINVAL;
1200 goto out_unlock;
1201 }
1202 if (!strcmp(sizestr, "max"))
1203 new_size = device->bdev->bd_inode->i_size;
1204 else {
1205 if (sizestr[0] == '-') {
1206 mod = -1;
1207 sizestr++;
1208 } else if (sizestr[0] == '+') {
1209 mod = 1;
1210 sizestr++;
1211 }
1212 new_size = memparse(sizestr, NULL);
1213 if (new_size == 0) {
1214 ret = -EINVAL;
1215 goto out_unlock;
1216 }
1217 }
1218
1219 old_size = device->total_bytes;
1220
1221 if (mod < 0) {
1222 if (new_size > old_size) {
1223 ret = -EINVAL;
1224 goto out_unlock;
1225 }
1226 new_size = old_size - new_size;
1227 } else if (mod > 0) {
1228 new_size = old_size + new_size;
1229 }
1230
1231 if (new_size < 256 * 1024 * 1024) {
1232 ret = -EINVAL;
1233 goto out_unlock;
1234 }
1235 if (new_size > device->bdev->bd_inode->i_size) {
1236 ret = -EFBIG;
1237 goto out_unlock;
1238 }
1239
1240 do_div(new_size, root->sectorsize);
1241 new_size *= root->sectorsize;
1242
1243 printk(KERN_INFO "new size for %s is %llu\n",
1244 device->name, (unsigned long long)new_size);
1245
1246 if (new_size > old_size) {
1247 trans = btrfs_start_transaction(root, 0);
1248 if (IS_ERR(trans)) {
1249 ret = PTR_ERR(trans);
1250 goto out_unlock;
1251 }
1252 ret = btrfs_grow_device(trans, device, new_size);
1253 btrfs_commit_transaction(trans, root);
1254 } else {
1255 ret = btrfs_shrink_device(device, new_size);
1256 }
1257
1258out_unlock:
1259 mutex_unlock(&root->fs_info->volume_mutex);
1260 kfree(vol_args);
1261 return ret;
1262}
1263
1264static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1265 char *name,
1266 unsigned long fd,
1267 int subvol,
1268 u64 *transid,
1269 bool readonly)
1270{
1271 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1272 struct file *src_file;
1273 int namelen;
1274 int ret = 0;
1275
1276 if (root->fs_info->sb->s_flags & MS_RDONLY)
1277 return -EROFS;
1278
1279 namelen = strlen(name);
1280 if (strchr(name, '/')) {
1281 ret = -EINVAL;
1282 goto out;
1283 }
1284
1285 if (subvol) {
1286 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1287 NULL, transid, readonly);
1288 } else {
1289 struct inode *src_inode;
1290 src_file = fget(fd);
1291 if (!src_file) {
1292 ret = -EINVAL;
1293 goto out;
1294 }
1295
1296 src_inode = src_file->f_path.dentry->d_inode;
1297 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1298 printk(KERN_INFO "btrfs: Snapshot src from "
1299 "another FS\n");
1300 ret = -EINVAL;
1301 fput(src_file);
1302 goto out;
1303 }
1304 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1305 BTRFS_I(src_inode)->root,
1306 transid, readonly);
1307 fput(src_file);
1308 }
1309out:
1310 return ret;
1311}
1312
1313static noinline int btrfs_ioctl_snap_create(struct file *file,
1314 void __user *arg, int subvol)
1315{
1316 struct btrfs_ioctl_vol_args *vol_args;
1317 int ret;
1318
1319 vol_args = memdup_user(arg, sizeof(*vol_args));
1320 if (IS_ERR(vol_args))
1321 return PTR_ERR(vol_args);
1322 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1323
1324 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1325 vol_args->fd, subvol,
1326 NULL, false);
1327
1328 kfree(vol_args);
1329 return ret;
1330}
1331
1332static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1333 void __user *arg, int subvol)
1334{
1335 struct btrfs_ioctl_vol_args_v2 *vol_args;
1336 int ret;
1337 u64 transid = 0;
1338 u64 *ptr = NULL;
1339 bool readonly = false;
1340
1341 vol_args = memdup_user(arg, sizeof(*vol_args));
1342 if (IS_ERR(vol_args))
1343 return PTR_ERR(vol_args);
1344 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1345
1346 if (vol_args->flags &
1347 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
1348 ret = -EOPNOTSUPP;
1349 goto out;
1350 }
1351
1352 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1353 ptr = &transid;
1354 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1355 readonly = true;
1356
1357 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1358 vol_args->fd, subvol,
1359 ptr, readonly);
1360
1361 if (ret == 0 && ptr &&
1362 copy_to_user(arg +
1363 offsetof(struct btrfs_ioctl_vol_args_v2,
1364 transid), ptr, sizeof(*ptr)))
1365 ret = -EFAULT;
1366out:
1367 kfree(vol_args);
1368 return ret;
1369}
1370
1371static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1372 void __user *arg)
1373{
1374 struct inode *inode = fdentry(file)->d_inode;
1375 struct btrfs_root *root = BTRFS_I(inode)->root;
1376 int ret = 0;
1377 u64 flags = 0;
1378
1379 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1380 return -EINVAL;
1381
1382 down_read(&root->fs_info->subvol_sem);
1383 if (btrfs_root_readonly(root))
1384 flags |= BTRFS_SUBVOL_RDONLY;
1385 up_read(&root->fs_info->subvol_sem);
1386
1387 if (copy_to_user(arg, &flags, sizeof(flags)))
1388 ret = -EFAULT;
1389
1390 return ret;
1391}
1392
1393static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1394 void __user *arg)
1395{
1396 struct inode *inode = fdentry(file)->d_inode;
1397 struct btrfs_root *root = BTRFS_I(inode)->root;
1398 struct btrfs_trans_handle *trans;
1399 u64 root_flags;
1400 u64 flags;
1401 int ret = 0;
1402
1403 if (root->fs_info->sb->s_flags & MS_RDONLY)
1404 return -EROFS;
1405
1406 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1407 return -EINVAL;
1408
1409 if (copy_from_user(&flags, arg, sizeof(flags)))
1410 return -EFAULT;
1411
1412 if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
1413 return -EINVAL;
1414
1415 if (flags & ~BTRFS_SUBVOL_RDONLY)
1416 return -EOPNOTSUPP;
1417
1418 if (!inode_owner_or_capable(inode))
1419 return -EACCES;
1420
1421 down_write(&root->fs_info->subvol_sem);
1422
1423 /* nothing to do */
1424 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1425 goto out;
1426
1427 root_flags = btrfs_root_flags(&root->root_item);
1428 if (flags & BTRFS_SUBVOL_RDONLY)
1429 btrfs_set_root_flags(&root->root_item,
1430 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1431 else
1432 btrfs_set_root_flags(&root->root_item,
1433 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1434
1435 trans = btrfs_start_transaction(root, 1);
1436 if (IS_ERR(trans)) {
1437 ret = PTR_ERR(trans);
1438 goto out_reset;
1439 }
1440
1441 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1442 &root->root_key, &root->root_item);
1443
1444 btrfs_commit_transaction(trans, root);
1445out_reset:
1446 if (ret)
1447 btrfs_set_root_flags(&root->root_item, root_flags);
1448out:
1449 up_write(&root->fs_info->subvol_sem);
1450 return ret;
1451}
1452
1453/*
1454 * helper to check if the subvolume references other subvolumes
1455 */
1456static noinline int may_destroy_subvol(struct btrfs_root *root)
1457{
1458 struct btrfs_path *path;
1459 struct btrfs_key key;
1460 int ret;
1461
1462 path = btrfs_alloc_path();
1463 if (!path)
1464 return -ENOMEM;
1465
1466 key.objectid = root->root_key.objectid;
1467 key.type = BTRFS_ROOT_REF_KEY;
1468 key.offset = (u64)-1;
1469
1470 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1471 &key, path, 0, 0);
1472 if (ret < 0)
1473 goto out;
1474 BUG_ON(ret == 0);
1475
1476 ret = 0;
1477 if (path->slots[0] > 0) {
1478 path->slots[0]--;
1479 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1480 if (key.objectid == root->root_key.objectid &&
1481 key.type == BTRFS_ROOT_REF_KEY)
1482 ret = -ENOTEMPTY;
1483 }
1484out:
1485 btrfs_free_path(path);
1486 return ret;
1487}
1488
1489static noinline int key_in_sk(struct btrfs_key *key,
1490 struct btrfs_ioctl_search_key *sk)
1491{
1492 struct btrfs_key test;
1493 int ret;
1494
1495 test.objectid = sk->min_objectid;
1496 test.type = sk->min_type;
1497 test.offset = sk->min_offset;
1498
1499 ret = btrfs_comp_cpu_keys(key, &test);
1500 if (ret < 0)
1501 return 0;
1502
1503 test.objectid = sk->max_objectid;
1504 test.type = sk->max_type;
1505 test.offset = sk->max_offset;
1506
1507 ret = btrfs_comp_cpu_keys(key, &test);
1508 if (ret > 0)
1509 return 0;
1510 return 1;
1511}
1512
1513static noinline int copy_to_sk(struct btrfs_root *root,
1514 struct btrfs_path *path,
1515 struct btrfs_key *key,
1516 struct btrfs_ioctl_search_key *sk,
1517 char *buf,
1518 unsigned long *sk_offset,
1519 int *num_found)
1520{
1521 u64 found_transid;
1522 struct extent_buffer *leaf;
1523 struct btrfs_ioctl_search_header sh;
1524 unsigned long item_off;
1525 unsigned long item_len;
1526 int nritems;
1527 int i;
1528 int slot;
1529 int ret = 0;
1530
1531 leaf = path->nodes[0];
1532 slot = path->slots[0];
1533 nritems = btrfs_header_nritems(leaf);
1534
1535 if (btrfs_header_generation(leaf) > sk->max_transid) {
1536 i = nritems;
1537 goto advance_key;
1538 }
1539 found_transid = btrfs_header_generation(leaf);
1540
1541 for (i = slot; i < nritems; i++) {
1542 item_off = btrfs_item_ptr_offset(leaf, i);
1543 item_len = btrfs_item_size_nr(leaf, i);
1544
1545 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1546 item_len = 0;
1547
1548 if (sizeof(sh) + item_len + *sk_offset >
1549 BTRFS_SEARCH_ARGS_BUFSIZE) {
1550 ret = 1;
1551 goto overflow;
1552 }
1553
1554 btrfs_item_key_to_cpu(leaf, key, i);
1555 if (!key_in_sk(key, sk))
1556 continue;
1557
1558 sh.objectid = key->objectid;
1559 sh.offset = key->offset;
1560 sh.type = key->type;
1561 sh.len = item_len;
1562 sh.transid = found_transid;
1563
1564 /* copy search result header */
1565 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1566 *sk_offset += sizeof(sh);
1567
1568 if (item_len) {
1569 char *p = buf + *sk_offset;
1570 /* copy the item */
1571 read_extent_buffer(leaf, p,
1572 item_off, item_len);
1573 *sk_offset += item_len;
1574 }
1575 (*num_found)++;
1576
1577 if (*num_found >= sk->nr_items)
1578 break;
1579 }
1580advance_key:
1581 ret = 0;
1582 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1583 key->offset++;
1584 else if (key->type < (u8)-1 && key->type < sk->max_type) {
1585 key->offset = 0;
1586 key->type++;
1587 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1588 key->offset = 0;
1589 key->type = 0;
1590 key->objectid++;
1591 } else
1592 ret = 1;
1593overflow:
1594 return ret;
1595}
1596
1597static noinline int search_ioctl(struct inode *inode,
1598 struct btrfs_ioctl_search_args *args)
1599{
1600 struct btrfs_root *root;
1601 struct btrfs_key key;
1602 struct btrfs_key max_key;
1603 struct btrfs_path *path;
1604 struct btrfs_ioctl_search_key *sk = &args->key;
1605 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1606 int ret;
1607 int num_found = 0;
1608 unsigned long sk_offset = 0;
1609
1610 path = btrfs_alloc_path();
1611 if (!path)
1612 return -ENOMEM;
1613
1614 if (sk->tree_id == 0) {
1615 /* search the root of the inode that was passed */
1616 root = BTRFS_I(inode)->root;
1617 } else {
1618 key.objectid = sk->tree_id;
1619 key.type = BTRFS_ROOT_ITEM_KEY;
1620 key.offset = (u64)-1;
1621 root = btrfs_read_fs_root_no_name(info, &key);
1622 if (IS_ERR(root)) {
1623 printk(KERN_ERR "could not find root %llu\n",
1624 sk->tree_id);
1625 btrfs_free_path(path);
1626 return -ENOENT;
1627 }
1628 }
1629
1630 key.objectid = sk->min_objectid;
1631 key.type = sk->min_type;
1632 key.offset = sk->min_offset;
1633
1634 max_key.objectid = sk->max_objectid;
1635 max_key.type = sk->max_type;
1636 max_key.offset = sk->max_offset;
1637
1638 path->keep_locks = 1;
1639
1640 while(1) {
1641 ret = btrfs_search_forward(root, &key, &max_key, path, 0,
1642 sk->min_transid);
1643 if (ret != 0) {
1644 if (ret > 0)
1645 ret = 0;
1646 goto err;
1647 }
1648 ret = copy_to_sk(root, path, &key, sk, args->buf,
1649 &sk_offset, &num_found);
1650 btrfs_release_path(path);
1651 if (ret || num_found >= sk->nr_items)
1652 break;
1653
1654 }
1655 ret = 0;
1656err:
1657 sk->nr_items = num_found;
1658 btrfs_free_path(path);
1659 return ret;
1660}
1661
1662static noinline int btrfs_ioctl_tree_search(struct file *file,
1663 void __user *argp)
1664{
1665 struct btrfs_ioctl_search_args *args;
1666 struct inode *inode;
1667 int ret;
1668
1669 if (!capable(CAP_SYS_ADMIN))
1670 return -EPERM;
1671
1672 args = memdup_user(argp, sizeof(*args));
1673 if (IS_ERR(args))
1674 return PTR_ERR(args);
1675
1676 inode = fdentry(file)->d_inode;
1677 ret = search_ioctl(inode, args);
1678 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1679 ret = -EFAULT;
1680 kfree(args);
1681 return ret;
1682}
1683
1684/*
1685 * Search INODE_REFs to identify path name of 'dirid' directory
1686 * in a 'tree_id' tree. and sets path name to 'name'.
1687 */
1688static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1689 u64 tree_id, u64 dirid, char *name)
1690{
1691 struct btrfs_root *root;
1692 struct btrfs_key key;
1693 char *ptr;
1694 int ret = -1;
1695 int slot;
1696 int len;
1697 int total_len = 0;
1698 struct btrfs_inode_ref *iref;
1699 struct extent_buffer *l;
1700 struct btrfs_path *path;
1701
1702 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1703 name[0]='\0';
1704 return 0;
1705 }
1706
1707 path = btrfs_alloc_path();
1708 if (!path)
1709 return -ENOMEM;
1710
1711 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1712
1713 key.objectid = tree_id;
1714 key.type = BTRFS_ROOT_ITEM_KEY;
1715 key.offset = (u64)-1;
1716 root = btrfs_read_fs_root_no_name(info, &key);
1717 if (IS_ERR(root)) {
1718 printk(KERN_ERR "could not find root %llu\n", tree_id);
1719 ret = -ENOENT;
1720 goto out;
1721 }
1722
1723 key.objectid = dirid;
1724 key.type = BTRFS_INODE_REF_KEY;
1725 key.offset = (u64)-1;
1726
1727 while(1) {
1728 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1729 if (ret < 0)
1730 goto out;
1731
1732 l = path->nodes[0];
1733 slot = path->slots[0];
1734 if (ret > 0 && slot > 0)
1735 slot--;
1736 btrfs_item_key_to_cpu(l, &key, slot);
1737
1738 if (ret > 0 && (key.objectid != dirid ||
1739 key.type != BTRFS_INODE_REF_KEY)) {
1740 ret = -ENOENT;
1741 goto out;
1742 }
1743
1744 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1745 len = btrfs_inode_ref_name_len(l, iref);
1746 ptr -= len + 1;
1747 total_len += len + 1;
1748 if (ptr < name)
1749 goto out;
1750
1751 *(ptr + len) = '/';
1752 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1753
1754 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1755 break;
1756
1757 btrfs_release_path(path);
1758 key.objectid = key.offset;
1759 key.offset = (u64)-1;
1760 dirid = key.objectid;
1761 }
1762 if (ptr < name)
1763 goto out;
1764 memmove(name, ptr, total_len);
1765 name[total_len]='\0';
1766 ret = 0;
1767out:
1768 btrfs_free_path(path);
1769 return ret;
1770}
1771
1772static noinline int btrfs_ioctl_ino_lookup(struct file *file,
1773 void __user *argp)
1774{
1775 struct btrfs_ioctl_ino_lookup_args *args;
1776 struct inode *inode;
1777 int ret;
1778
1779 if (!capable(CAP_SYS_ADMIN))
1780 return -EPERM;
1781
1782 args = memdup_user(argp, sizeof(*args));
1783 if (IS_ERR(args))
1784 return PTR_ERR(args);
1785
1786 inode = fdentry(file)->d_inode;
1787
1788 if (args->treeid == 0)
1789 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
1790
1791 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
1792 args->treeid, args->objectid,
1793 args->name);
1794
1795 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1796 ret = -EFAULT;
1797
1798 kfree(args);
1799 return ret;
1800}
1801
1802static noinline int btrfs_ioctl_snap_destroy(struct file *file,
1803 void __user *arg)
1804{
1805 struct dentry *parent = fdentry(file);
1806 struct dentry *dentry;
1807 struct inode *dir = parent->d_inode;
1808 struct inode *inode;
1809 struct btrfs_root *root = BTRFS_I(dir)->root;
1810 struct btrfs_root *dest = NULL;
1811 struct btrfs_ioctl_vol_args *vol_args;
1812 struct btrfs_trans_handle *trans;
1813 int namelen;
1814 int ret;
1815 int err = 0;
1816
1817 vol_args = memdup_user(arg, sizeof(*vol_args));
1818 if (IS_ERR(vol_args))
1819 return PTR_ERR(vol_args);
1820
1821 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1822 namelen = strlen(vol_args->name);
1823 if (strchr(vol_args->name, '/') ||
1824 strncmp(vol_args->name, "..", namelen) == 0) {
1825 err = -EINVAL;
1826 goto out;
1827 }
1828
1829 err = mnt_want_write(file->f_path.mnt);
1830 if (err)
1831 goto out;
1832
1833 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
1834 dentry = lookup_one_len(vol_args->name, parent, namelen);
1835 if (IS_ERR(dentry)) {
1836 err = PTR_ERR(dentry);
1837 goto out_unlock_dir;
1838 }
1839
1840 if (!dentry->d_inode) {
1841 err = -ENOENT;
1842 goto out_dput;
1843 }
1844
1845 inode = dentry->d_inode;
1846 dest = BTRFS_I(inode)->root;
1847 if (!capable(CAP_SYS_ADMIN)){
1848 /*
1849 * Regular user. Only allow this with a special mount
1850 * option, when the user has write+exec access to the
1851 * subvol root, and when rmdir(2) would have been
1852 * allowed.
1853 *
1854 * Note that this is _not_ check that the subvol is
1855 * empty or doesn't contain data that we wouldn't
1856 * otherwise be able to delete.
1857 *
1858 * Users who want to delete empty subvols should try
1859 * rmdir(2).
1860 */
1861 err = -EPERM;
1862 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
1863 goto out_dput;
1864
1865 /*
1866 * Do not allow deletion if the parent dir is the same
1867 * as the dir to be deleted. That means the ioctl
1868 * must be called on the dentry referencing the root
1869 * of the subvol, not a random directory contained
1870 * within it.
1871 */
1872 err = -EINVAL;
1873 if (root == dest)
1874 goto out_dput;
1875
1876 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
1877 if (err)
1878 goto out_dput;
1879
1880 /* check if subvolume may be deleted by a non-root user */
1881 err = btrfs_may_delete(dir, dentry, 1);
1882 if (err)
1883 goto out_dput;
1884 }
1885
1886 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1887 err = -EINVAL;
1888 goto out_dput;
1889 }
1890
1891 mutex_lock(&inode->i_mutex);
1892 err = d_invalidate(dentry);
1893 if (err)
1894 goto out_unlock;
1895
1896 down_write(&root->fs_info->subvol_sem);
1897
1898 err = may_destroy_subvol(dest);
1899 if (err)
1900 goto out_up_write;
1901
1902 trans = btrfs_start_transaction(root, 0);
1903 if (IS_ERR(trans)) {
1904 err = PTR_ERR(trans);
1905 goto out_up_write;
1906 }
1907 trans->block_rsv = &root->fs_info->global_block_rsv;
1908
1909 ret = btrfs_unlink_subvol(trans, root, dir,
1910 dest->root_key.objectid,
1911 dentry->d_name.name,
1912 dentry->d_name.len);
1913 BUG_ON(ret);
1914
1915 btrfs_record_root_in_trans(trans, dest);
1916
1917 memset(&dest->root_item.drop_progress, 0,
1918 sizeof(dest->root_item.drop_progress));
1919 dest->root_item.drop_level = 0;
1920 btrfs_set_root_refs(&dest->root_item, 0);
1921
1922 if (!xchg(&dest->orphan_item_inserted, 1)) {
1923 ret = btrfs_insert_orphan_item(trans,
1924 root->fs_info->tree_root,
1925 dest->root_key.objectid);
1926 BUG_ON(ret);
1927 }
1928
1929 ret = btrfs_end_transaction(trans, root);
1930 BUG_ON(ret);
1931 inode->i_flags |= S_DEAD;
1932out_up_write:
1933 up_write(&root->fs_info->subvol_sem);
1934out_unlock:
1935 mutex_unlock(&inode->i_mutex);
1936 if (!err) {
1937 shrink_dcache_sb(root->fs_info->sb);
1938 btrfs_invalidate_inodes(dest);
1939 d_delete(dentry);
1940 }
1941out_dput:
1942 dput(dentry);
1943out_unlock_dir:
1944 mutex_unlock(&dir->i_mutex);
1945 mnt_drop_write(file->f_path.mnt);
1946out:
1947 kfree(vol_args);
1948 return err;
1949}
1950
1951static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
1952{
1953 struct inode *inode = fdentry(file)->d_inode;
1954 struct btrfs_root *root = BTRFS_I(inode)->root;
1955 struct btrfs_ioctl_defrag_range_args *range;
1956 int ret;
1957
1958 if (btrfs_root_readonly(root))
1959 return -EROFS;
1960
1961 ret = mnt_want_write(file->f_path.mnt);
1962 if (ret)
1963 return ret;
1964
1965 switch (inode->i_mode & S_IFMT) {
1966 case S_IFDIR:
1967 if (!capable(CAP_SYS_ADMIN)) {
1968 ret = -EPERM;
1969 goto out;
1970 }
1971 ret = btrfs_defrag_root(root, 0);
1972 if (ret)
1973 goto out;
1974 ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
1975 break;
1976 case S_IFREG:
1977 if (!(file->f_mode & FMODE_WRITE)) {
1978 ret = -EINVAL;
1979 goto out;
1980 }
1981
1982 range = kzalloc(sizeof(*range), GFP_KERNEL);
1983 if (!range) {
1984 ret = -ENOMEM;
1985 goto out;
1986 }
1987
1988 if (argp) {
1989 if (copy_from_user(range, argp,
1990 sizeof(*range))) {
1991 ret = -EFAULT;
1992 kfree(range);
1993 goto out;
1994 }
1995 /* compression requires us to start the IO */
1996 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1997 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
1998 range->extent_thresh = (u32)-1;
1999 }
2000 } else {
2001 /* the rest are all set to zero by kzalloc */
2002 range->len = (u64)-1;
2003 }
2004 ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
2005 range, 0, 0);
2006 if (ret > 0)
2007 ret = 0;
2008 kfree(range);
2009 break;
2010 default:
2011 ret = -EINVAL;
2012 }
2013out:
2014 mnt_drop_write(file->f_path.mnt);
2015 return ret;
2016}
2017
2018static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2019{
2020 struct btrfs_ioctl_vol_args *vol_args;
2021 int ret;
2022
2023 if (!capable(CAP_SYS_ADMIN))
2024 return -EPERM;
2025
2026 vol_args = memdup_user(arg, sizeof(*vol_args));
2027 if (IS_ERR(vol_args))
2028 return PTR_ERR(vol_args);
2029
2030 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2031 ret = btrfs_init_new_device(root, vol_args->name);
2032
2033 kfree(vol_args);
2034 return ret;
2035}
2036
2037static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
2038{
2039 struct btrfs_ioctl_vol_args *vol_args;
2040 int ret;
2041
2042 if (!capable(CAP_SYS_ADMIN))
2043 return -EPERM;
2044
2045 if (root->fs_info->sb->s_flags & MS_RDONLY)
2046 return -EROFS;
2047
2048 vol_args = memdup_user(arg, sizeof(*vol_args));
2049 if (IS_ERR(vol_args))
2050 return PTR_ERR(vol_args);
2051
2052 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2053 ret = btrfs_rm_device(root, vol_args->name);
2054
2055 kfree(vol_args);
2056 return ret;
2057}
2058
2059static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2060{
2061 struct btrfs_ioctl_fs_info_args *fi_args;
2062 struct btrfs_device *device;
2063 struct btrfs_device *next;
2064 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2065 int ret = 0;
2066
2067 if (!capable(CAP_SYS_ADMIN))
2068 return -EPERM;
2069
2070 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2071 if (!fi_args)
2072 return -ENOMEM;
2073
2074 fi_args->num_devices = fs_devices->num_devices;
2075 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2076
2077 mutex_lock(&fs_devices->device_list_mutex);
2078 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2079 if (device->devid > fi_args->max_id)
2080 fi_args->max_id = device->devid;
2081 }
2082 mutex_unlock(&fs_devices->device_list_mutex);
2083
2084 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2085 ret = -EFAULT;
2086
2087 kfree(fi_args);
2088 return ret;
2089}
2090
2091static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2092{
2093 struct btrfs_ioctl_dev_info_args *di_args;
2094 struct btrfs_device *dev;
2095 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2096 int ret = 0;
2097 char *s_uuid = NULL;
2098 char empty_uuid[BTRFS_UUID_SIZE] = {0};
2099
2100 if (!capable(CAP_SYS_ADMIN))
2101 return -EPERM;
2102
2103 di_args = memdup_user(arg, sizeof(*di_args));
2104 if (IS_ERR(di_args))
2105 return PTR_ERR(di_args);
2106
2107 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2108 s_uuid = di_args->uuid;
2109
2110 mutex_lock(&fs_devices->device_list_mutex);
2111 dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL);
2112 mutex_unlock(&fs_devices->device_list_mutex);
2113
2114 if (!dev) {
2115 ret = -ENODEV;
2116 goto out;
2117 }
2118
2119 di_args->devid = dev->devid;
2120 di_args->bytes_used = dev->bytes_used;
2121 di_args->total_bytes = dev->total_bytes;
2122 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2123 strncpy(di_args->path, dev->name, sizeof(di_args->path));
2124
2125out:
2126 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2127 ret = -EFAULT;
2128
2129 kfree(di_args);
2130 return ret;
2131}
2132
2133static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2134 u64 off, u64 olen, u64 destoff)
2135{
2136 struct inode *inode = fdentry(file)->d_inode;
2137 struct btrfs_root *root = BTRFS_I(inode)->root;
2138 struct file *src_file;
2139 struct inode *src;
2140 struct btrfs_trans_handle *trans;
2141 struct btrfs_path *path;
2142 struct extent_buffer *leaf;
2143 char *buf;
2144 struct btrfs_key key;
2145 u32 nritems;
2146 int slot;
2147 int ret;
2148 u64 len = olen;
2149 u64 bs = root->fs_info->sb->s_blocksize;
2150 u64 hint_byte;
2151
2152 /*
2153 * TODO:
2154 * - split compressed inline extents. annoying: we need to
2155 * decompress into destination's address_space (the file offset
2156 * may change, so source mapping won't do), then recompress (or
2157 * otherwise reinsert) a subrange.
2158 * - allow ranges within the same file to be cloned (provided
2159 * they don't overlap)?
2160 */
2161
2162 /* the destination must be opened for writing */
2163 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2164 return -EINVAL;
2165
2166 if (btrfs_root_readonly(root))
2167 return -EROFS;
2168
2169 ret = mnt_want_write(file->f_path.mnt);
2170 if (ret)
2171 return ret;
2172
2173 src_file = fget(srcfd);
2174 if (!src_file) {
2175 ret = -EBADF;
2176 goto out_drop_write;
2177 }
2178
2179 src = src_file->f_dentry->d_inode;
2180
2181 ret = -EINVAL;
2182 if (src == inode)
2183 goto out_fput;
2184
2185 /* the src must be open for reading */
2186 if (!(src_file->f_mode & FMODE_READ))
2187 goto out_fput;
2188
2189 /* don't make the dst file partly checksummed */
2190 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2191 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2192 goto out_fput;
2193
2194 ret = -EISDIR;
2195 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2196 goto out_fput;
2197
2198 ret = -EXDEV;
2199 if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
2200 goto out_fput;
2201
2202 ret = -ENOMEM;
2203 buf = vmalloc(btrfs_level_size(root, 0));
2204 if (!buf)
2205 goto out_fput;
2206
2207 path = btrfs_alloc_path();
2208 if (!path) {
2209 vfree(buf);
2210 goto out_fput;
2211 }
2212 path->reada = 2;
2213
2214 if (inode < src) {
2215 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2216 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2217 } else {
2218 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2219 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2220 }
2221
2222 /* determine range to clone */
2223 ret = -EINVAL;
2224 if (off + len > src->i_size || off + len < off)
2225 goto out_unlock;
2226 if (len == 0)
2227 olen = len = src->i_size - off;
2228 /* if we extend to eof, continue to block boundary */
2229 if (off + len == src->i_size)
2230 len = ALIGN(src->i_size, bs) - off;
2231
2232 /* verify the end result is block aligned */
2233 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2234 !IS_ALIGNED(destoff, bs))
2235 goto out_unlock;
2236
2237 if (destoff > inode->i_size) {
2238 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2239 if (ret)
2240 goto out_unlock;
2241 }
2242
2243 /* truncate page cache pages from target inode range */
2244 truncate_inode_pages_range(&inode->i_data, destoff,
2245 PAGE_CACHE_ALIGN(destoff + len) - 1);
2246
2247 /* do any pending delalloc/csum calc on src, one way or
2248 another, and lock file content */
2249 while (1) {
2250 struct btrfs_ordered_extent *ordered;
2251 lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2252 ordered = btrfs_lookup_first_ordered_extent(src, off+len);
2253 if (!ordered &&
2254 !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len,
2255 EXTENT_DELALLOC, 0, NULL))
2256 break;
2257 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2258 if (ordered)
2259 btrfs_put_ordered_extent(ordered);
2260 btrfs_wait_ordered_range(src, off, len);
2261 }
2262
2263 /* clone data */
2264 key.objectid = btrfs_ino(src);
2265 key.type = BTRFS_EXTENT_DATA_KEY;
2266 key.offset = 0;
2267
2268 while (1) {
2269 /*
2270 * note the key will change type as we walk through the
2271 * tree.
2272 */
2273 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2274 if (ret < 0)
2275 goto out;
2276
2277 nritems = btrfs_header_nritems(path->nodes[0]);
2278 if (path->slots[0] >= nritems) {
2279 ret = btrfs_next_leaf(root, path);
2280 if (ret < 0)
2281 goto out;
2282 if (ret > 0)
2283 break;
2284 nritems = btrfs_header_nritems(path->nodes[0]);
2285 }
2286 leaf = path->nodes[0];
2287 slot = path->slots[0];
2288
2289 btrfs_item_key_to_cpu(leaf, &key, slot);
2290 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2291 key.objectid != btrfs_ino(src))
2292 break;
2293
2294 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2295 struct btrfs_file_extent_item *extent;
2296 int type;
2297 u32 size;
2298 struct btrfs_key new_key;
2299 u64 disko = 0, diskl = 0;
2300 u64 datao = 0, datal = 0;
2301 u8 comp;
2302 u64 endoff;
2303
2304 size = btrfs_item_size_nr(leaf, slot);
2305 read_extent_buffer(leaf, buf,
2306 btrfs_item_ptr_offset(leaf, slot),
2307 size);
2308
2309 extent = btrfs_item_ptr(leaf, slot,
2310 struct btrfs_file_extent_item);
2311 comp = btrfs_file_extent_compression(leaf, extent);
2312 type = btrfs_file_extent_type(leaf, extent);
2313 if (type == BTRFS_FILE_EXTENT_REG ||
2314 type == BTRFS_FILE_EXTENT_PREALLOC) {
2315 disko = btrfs_file_extent_disk_bytenr(leaf,
2316 extent);
2317 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2318 extent);
2319 datao = btrfs_file_extent_offset(leaf, extent);
2320 datal = btrfs_file_extent_num_bytes(leaf,
2321 extent);
2322 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2323 /* take upper bound, may be compressed */
2324 datal = btrfs_file_extent_ram_bytes(leaf,
2325 extent);
2326 }
2327 btrfs_release_path(path);
2328
2329 if (key.offset + datal <= off ||
2330 key.offset >= off+len)
2331 goto next;
2332
2333 memcpy(&new_key, &key, sizeof(new_key));
2334 new_key.objectid = btrfs_ino(inode);
2335 if (off <= key.offset)
2336 new_key.offset = key.offset + destoff - off;
2337 else
2338 new_key.offset = destoff;
2339
2340 /*
2341 * 1 - adjusting old extent (we may have to split it)
2342 * 1 - add new extent
2343 * 1 - inode update
2344 */
2345 trans = btrfs_start_transaction(root, 3);
2346 if (IS_ERR(trans)) {
2347 ret = PTR_ERR(trans);
2348 goto out;
2349 }
2350
2351 if (type == BTRFS_FILE_EXTENT_REG ||
2352 type == BTRFS_FILE_EXTENT_PREALLOC) {
2353 /*
2354 * a | --- range to clone ---| b
2355 * | ------------- extent ------------- |
2356 */
2357
2358 /* substract range b */
2359 if (key.offset + datal > off + len)
2360 datal = off + len - key.offset;
2361
2362 /* substract range a */
2363 if (off > key.offset) {
2364 datao += off - key.offset;
2365 datal -= off - key.offset;
2366 }
2367
2368 ret = btrfs_drop_extents(trans, inode,
2369 new_key.offset,
2370 new_key.offset + datal,
2371 &hint_byte, 1);
2372 BUG_ON(ret);
2373
2374 ret = btrfs_insert_empty_item(trans, root, path,
2375 &new_key, size);
2376 BUG_ON(ret);
2377
2378 leaf = path->nodes[0];
2379 slot = path->slots[0];
2380 write_extent_buffer(leaf, buf,
2381 btrfs_item_ptr_offset(leaf, slot),
2382 size);
2383
2384 extent = btrfs_item_ptr(leaf, slot,
2385 struct btrfs_file_extent_item);
2386
2387 /* disko == 0 means it's a hole */
2388 if (!disko)
2389 datao = 0;
2390
2391 btrfs_set_file_extent_offset(leaf, extent,
2392 datao);
2393 btrfs_set_file_extent_num_bytes(leaf, extent,
2394 datal);
2395 if (disko) {
2396 inode_add_bytes(inode, datal);
2397 ret = btrfs_inc_extent_ref(trans, root,
2398 disko, diskl, 0,
2399 root->root_key.objectid,
2400 btrfs_ino(inode),
2401 new_key.offset - datao);
2402 BUG_ON(ret);
2403 }
2404 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2405 u64 skip = 0;
2406 u64 trim = 0;
2407 if (off > key.offset) {
2408 skip = off - key.offset;
2409 new_key.offset += skip;
2410 }
2411
2412 if (key.offset + datal > off+len)
2413 trim = key.offset + datal - (off+len);
2414
2415 if (comp && (skip || trim)) {
2416 ret = -EINVAL;
2417 btrfs_end_transaction(trans, root);
2418 goto out;
2419 }
2420 size -= skip + trim;
2421 datal -= skip + trim;
2422
2423 ret = btrfs_drop_extents(trans, inode,
2424 new_key.offset,
2425 new_key.offset + datal,
2426 &hint_byte, 1);
2427 BUG_ON(ret);
2428
2429 ret = btrfs_insert_empty_item(trans, root, path,
2430 &new_key, size);
2431 BUG_ON(ret);
2432
2433 if (skip) {
2434 u32 start =
2435 btrfs_file_extent_calc_inline_size(0);
2436 memmove(buf+start, buf+start+skip,
2437 datal);
2438 }
2439
2440 leaf = path->nodes[0];
2441 slot = path->slots[0];
2442 write_extent_buffer(leaf, buf,
2443 btrfs_item_ptr_offset(leaf, slot),
2444 size);
2445 inode_add_bytes(inode, datal);
2446 }
2447
2448 btrfs_mark_buffer_dirty(leaf);
2449 btrfs_release_path(path);
2450
2451 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2452
2453 /*
2454 * we round up to the block size at eof when
2455 * determining which extents to clone above,
2456 * but shouldn't round up the file size
2457 */
2458 endoff = new_key.offset + datal;
2459 if (endoff > destoff+olen)
2460 endoff = destoff+olen;
2461 if (endoff > inode->i_size)
2462 btrfs_i_size_write(inode, endoff);
2463
2464 ret = btrfs_update_inode(trans, root, inode);
2465 BUG_ON(ret);
2466 btrfs_end_transaction(trans, root);
2467 }
2468next:
2469 btrfs_release_path(path);
2470 key.offset++;
2471 }
2472 ret = 0;
2473out:
2474 btrfs_release_path(path);
2475 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2476out_unlock:
2477 mutex_unlock(&src->i_mutex);
2478 mutex_unlock(&inode->i_mutex);
2479 vfree(buf);
2480 btrfs_free_path(path);
2481out_fput:
2482 fput(src_file);
2483out_drop_write:
2484 mnt_drop_write(file->f_path.mnt);
2485 return ret;
2486}
2487
2488static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2489{
2490 struct btrfs_ioctl_clone_range_args args;
2491
2492 if (copy_from_user(&args, argp, sizeof(args)))
2493 return -EFAULT;
2494 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2495 args.src_length, args.dest_offset);
2496}
2497
2498/*
2499 * there are many ways the trans_start and trans_end ioctls can lead
2500 * to deadlocks. They should only be used by applications that
2501 * basically own the machine, and have a very in depth understanding
2502 * of all the possible deadlocks and enospc problems.
2503 */
2504static long btrfs_ioctl_trans_start(struct file *file)
2505{
2506 struct inode *inode = fdentry(file)->d_inode;
2507 struct btrfs_root *root = BTRFS_I(inode)->root;
2508 struct btrfs_trans_handle *trans;
2509 int ret;
2510
2511 ret = -EPERM;
2512 if (!capable(CAP_SYS_ADMIN))
2513 goto out;
2514
2515 ret = -EINPROGRESS;
2516 if (file->private_data)
2517 goto out;
2518
2519 ret = -EROFS;
2520 if (btrfs_root_readonly(root))
2521 goto out;
2522
2523 ret = mnt_want_write(file->f_path.mnt);
2524 if (ret)
2525 goto out;
2526
2527 atomic_inc(&root->fs_info->open_ioctl_trans);
2528
2529 ret = -ENOMEM;
2530 trans = btrfs_start_ioctl_transaction(root);
2531 if (IS_ERR(trans))
2532 goto out_drop;
2533
2534 file->private_data = trans;
2535 return 0;
2536
2537out_drop:
2538 atomic_dec(&root->fs_info->open_ioctl_trans);
2539 mnt_drop_write(file->f_path.mnt);
2540out:
2541 return ret;
2542}
2543
2544static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2545{
2546 struct inode *inode = fdentry(file)->d_inode;
2547 struct btrfs_root *root = BTRFS_I(inode)->root;
2548 struct btrfs_root *new_root;
2549 struct btrfs_dir_item *di;
2550 struct btrfs_trans_handle *trans;
2551 struct btrfs_path *path;
2552 struct btrfs_key location;
2553 struct btrfs_disk_key disk_key;
2554 struct btrfs_super_block *disk_super;
2555 u64 features;
2556 u64 objectid = 0;
2557 u64 dir_id;
2558
2559 if (!capable(CAP_SYS_ADMIN))
2560 return -EPERM;
2561
2562 if (copy_from_user(&objectid, argp, sizeof(objectid)))
2563 return -EFAULT;
2564
2565 if (!objectid)
2566 objectid = root->root_key.objectid;
2567
2568 location.objectid = objectid;
2569 location.type = BTRFS_ROOT_ITEM_KEY;
2570 location.offset = (u64)-1;
2571
2572 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2573 if (IS_ERR(new_root))
2574 return PTR_ERR(new_root);
2575
2576 if (btrfs_root_refs(&new_root->root_item) == 0)
2577 return -ENOENT;
2578
2579 path = btrfs_alloc_path();
2580 if (!path)
2581 return -ENOMEM;
2582 path->leave_spinning = 1;
2583
2584 trans = btrfs_start_transaction(root, 1);
2585 if (IS_ERR(trans)) {
2586 btrfs_free_path(path);
2587 return PTR_ERR(trans);
2588 }
2589
2590 dir_id = btrfs_super_root_dir(&root->fs_info->super_copy);
2591 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2592 dir_id, "default", 7, 1);
2593 if (IS_ERR_OR_NULL(di)) {
2594 btrfs_free_path(path);
2595 btrfs_end_transaction(trans, root);
2596 printk(KERN_ERR "Umm, you don't have the default dir item, "
2597 "this isn't going to work\n");
2598 return -ENOENT;
2599 }
2600
2601 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2602 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2603 btrfs_mark_buffer_dirty(path->nodes[0]);
2604 btrfs_free_path(path);
2605
2606 disk_super = &root->fs_info->super_copy;
2607 features = btrfs_super_incompat_flags(disk_super);
2608 if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) {
2609 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL;
2610 btrfs_set_super_incompat_flags(disk_super, features);
2611 }
2612 btrfs_end_transaction(trans, root);
2613
2614 return 0;
2615}
2616
2617static void get_block_group_info(struct list_head *groups_list,
2618 struct btrfs_ioctl_space_info *space)
2619{
2620 struct btrfs_block_group_cache *block_group;
2621
2622 space->total_bytes = 0;
2623 space->used_bytes = 0;
2624 space->flags = 0;
2625 list_for_each_entry(block_group, groups_list, list) {
2626 space->flags = block_group->flags;
2627 space->total_bytes += block_group->key.offset;
2628 space->used_bytes +=
2629 btrfs_block_group_used(&block_group->item);
2630 }
2631}
2632
2633long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
2634{
2635 struct btrfs_ioctl_space_args space_args;
2636 struct btrfs_ioctl_space_info space;
2637 struct btrfs_ioctl_space_info *dest;
2638 struct btrfs_ioctl_space_info *dest_orig;
2639 struct btrfs_ioctl_space_info __user *user_dest;
2640 struct btrfs_space_info *info;
2641 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2642 BTRFS_BLOCK_GROUP_SYSTEM,
2643 BTRFS_BLOCK_GROUP_METADATA,
2644 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
2645 int num_types = 4;
2646 int alloc_size;
2647 int ret = 0;
2648 u64 slot_count = 0;
2649 int i, c;
2650
2651 if (copy_from_user(&space_args,
2652 (struct btrfs_ioctl_space_args __user *)arg,
2653 sizeof(space_args)))
2654 return -EFAULT;
2655
2656 for (i = 0; i < num_types; i++) {
2657 struct btrfs_space_info *tmp;
2658
2659 info = NULL;
2660 rcu_read_lock();
2661 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2662 list) {
2663 if (tmp->flags == types[i]) {
2664 info = tmp;
2665 break;
2666 }
2667 }
2668 rcu_read_unlock();
2669
2670 if (!info)
2671 continue;
2672
2673 down_read(&info->groups_sem);
2674 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2675 if (!list_empty(&info->block_groups[c]))
2676 slot_count++;
2677 }
2678 up_read(&info->groups_sem);
2679 }
2680
2681 /* space_slots == 0 means they are asking for a count */
2682 if (space_args.space_slots == 0) {
2683 space_args.total_spaces = slot_count;
2684 goto out;
2685 }
2686
2687 slot_count = min_t(u64, space_args.space_slots, slot_count);
2688
2689 alloc_size = sizeof(*dest) * slot_count;
2690
2691 /* we generally have at most 6 or so space infos, one for each raid
2692 * level. So, a whole page should be more than enough for everyone
2693 */
2694 if (alloc_size > PAGE_CACHE_SIZE)
2695 return -ENOMEM;
2696
2697 space_args.total_spaces = 0;
2698 dest = kmalloc(alloc_size, GFP_NOFS);
2699 if (!dest)
2700 return -ENOMEM;
2701 dest_orig = dest;
2702
2703 /* now we have a buffer to copy into */
2704 for (i = 0; i < num_types; i++) {
2705 struct btrfs_space_info *tmp;
2706
2707 if (!slot_count)
2708 break;
2709
2710 info = NULL;
2711 rcu_read_lock();
2712 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2713 list) {
2714 if (tmp->flags == types[i]) {
2715 info = tmp;
2716 break;
2717 }
2718 }
2719 rcu_read_unlock();
2720
2721 if (!info)
2722 continue;
2723 down_read(&info->groups_sem);
2724 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2725 if (!list_empty(&info->block_groups[c])) {
2726 get_block_group_info(&info->block_groups[c],
2727 &space);
2728 memcpy(dest, &space, sizeof(space));
2729 dest++;
2730 space_args.total_spaces++;
2731 slot_count--;
2732 }
2733 if (!slot_count)
2734 break;
2735 }
2736 up_read(&info->groups_sem);
2737 }
2738
2739 user_dest = (struct btrfs_ioctl_space_info *)
2740 (arg + sizeof(struct btrfs_ioctl_space_args));
2741
2742 if (copy_to_user(user_dest, dest_orig, alloc_size))
2743 ret = -EFAULT;
2744
2745 kfree(dest_orig);
2746out:
2747 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
2748 ret = -EFAULT;
2749
2750 return ret;
2751}
2752
2753/*
2754 * there are many ways the trans_start and trans_end ioctls can lead
2755 * to deadlocks. They should only be used by applications that
2756 * basically own the machine, and have a very in depth understanding
2757 * of all the possible deadlocks and enospc problems.
2758 */
2759long btrfs_ioctl_trans_end(struct file *file)
2760{
2761 struct inode *inode = fdentry(file)->d_inode;
2762 struct btrfs_root *root = BTRFS_I(inode)->root;
2763 struct btrfs_trans_handle *trans;
2764
2765 trans = file->private_data;
2766 if (!trans)
2767 return -EINVAL;
2768 file->private_data = NULL;
2769
2770 btrfs_end_transaction(trans, root);
2771
2772 atomic_dec(&root->fs_info->open_ioctl_trans);
2773
2774 mnt_drop_write(file->f_path.mnt);
2775 return 0;
2776}
2777
2778static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
2779{
2780 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2781 struct btrfs_trans_handle *trans;
2782 u64 transid;
2783 int ret;
2784
2785 trans = btrfs_start_transaction(root, 0);
2786 if (IS_ERR(trans))
2787 return PTR_ERR(trans);
2788 transid = trans->transid;
2789 ret = btrfs_commit_transaction_async(trans, root, 0);
2790 if (ret) {
2791 btrfs_end_transaction(trans, root);
2792 return ret;
2793 }
2794
2795 if (argp)
2796 if (copy_to_user(argp, &transid, sizeof(transid)))
2797 return -EFAULT;
2798 return 0;
2799}
2800
2801static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
2802{
2803 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2804 u64 transid;
2805
2806 if (argp) {
2807 if (copy_from_user(&transid, argp, sizeof(transid)))
2808 return -EFAULT;
2809 } else {
2810 transid = 0; /* current trans */
2811 }
2812 return btrfs_wait_for_commit(root, transid);
2813}
2814
2815static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg)
2816{
2817 int ret;
2818 struct btrfs_ioctl_scrub_args *sa;
2819
2820 if (!capable(CAP_SYS_ADMIN))
2821 return -EPERM;
2822
2823 sa = memdup_user(arg, sizeof(*sa));
2824 if (IS_ERR(sa))
2825 return PTR_ERR(sa);
2826
2827 ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end,
2828 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY);
2829
2830 if (copy_to_user(arg, sa, sizeof(*sa)))
2831 ret = -EFAULT;
2832
2833 kfree(sa);
2834 return ret;
2835}
2836
2837static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
2838{
2839 if (!capable(CAP_SYS_ADMIN))
2840 return -EPERM;
2841
2842 return btrfs_scrub_cancel(root);
2843}
2844
2845static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
2846 void __user *arg)
2847{
2848 struct btrfs_ioctl_scrub_args *sa;
2849 int ret;
2850
2851 if (!capable(CAP_SYS_ADMIN))
2852 return -EPERM;
2853
2854 sa = memdup_user(arg, sizeof(*sa));
2855 if (IS_ERR(sa))
2856 return PTR_ERR(sa);
2857
2858 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
2859
2860 if (copy_to_user(arg, sa, sizeof(*sa)))
2861 ret = -EFAULT;
2862
2863 kfree(sa);
2864 return ret;
2865}
2866
2867long btrfs_ioctl(struct file *file, unsigned int
2868 cmd, unsigned long arg)
2869{
2870 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2871 void __user *argp = (void __user *)arg;
2872
2873 switch (cmd) {
2874 case FS_IOC_GETFLAGS:
2875 return btrfs_ioctl_getflags(file, argp);
2876 case FS_IOC_SETFLAGS:
2877 return btrfs_ioctl_setflags(file, argp);
2878 case FS_IOC_GETVERSION:
2879 return btrfs_ioctl_getversion(file, argp);
2880 case FITRIM:
2881 return btrfs_ioctl_fitrim(file, argp);
2882 case BTRFS_IOC_SNAP_CREATE:
2883 return btrfs_ioctl_snap_create(file, argp, 0);
2884 case BTRFS_IOC_SNAP_CREATE_V2:
2885 return btrfs_ioctl_snap_create_v2(file, argp, 0);
2886 case BTRFS_IOC_SUBVOL_CREATE:
2887 return btrfs_ioctl_snap_create(file, argp, 1);
2888 case BTRFS_IOC_SNAP_DESTROY:
2889 return btrfs_ioctl_snap_destroy(file, argp);
2890 case BTRFS_IOC_SUBVOL_GETFLAGS:
2891 return btrfs_ioctl_subvol_getflags(file, argp);
2892 case BTRFS_IOC_SUBVOL_SETFLAGS:
2893 return btrfs_ioctl_subvol_setflags(file, argp);
2894 case BTRFS_IOC_DEFAULT_SUBVOL:
2895 return btrfs_ioctl_default_subvol(file, argp);
2896 case BTRFS_IOC_DEFRAG:
2897 return btrfs_ioctl_defrag(file, NULL);
2898 case BTRFS_IOC_DEFRAG_RANGE:
2899 return btrfs_ioctl_defrag(file, argp);
2900 case BTRFS_IOC_RESIZE:
2901 return btrfs_ioctl_resize(root, argp);
2902 case BTRFS_IOC_ADD_DEV:
2903 return btrfs_ioctl_add_dev(root, argp);
2904 case BTRFS_IOC_RM_DEV:
2905 return btrfs_ioctl_rm_dev(root, argp);
2906 case BTRFS_IOC_FS_INFO:
2907 return btrfs_ioctl_fs_info(root, argp);
2908 case BTRFS_IOC_DEV_INFO:
2909 return btrfs_ioctl_dev_info(root, argp);
2910 case BTRFS_IOC_BALANCE:
2911 return btrfs_balance(root->fs_info->dev_root);
2912 case BTRFS_IOC_CLONE:
2913 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
2914 case BTRFS_IOC_CLONE_RANGE:
2915 return btrfs_ioctl_clone_range(file, argp);
2916 case BTRFS_IOC_TRANS_START:
2917 return btrfs_ioctl_trans_start(file);
2918 case BTRFS_IOC_TRANS_END:
2919 return btrfs_ioctl_trans_end(file);
2920 case BTRFS_IOC_TREE_SEARCH:
2921 return btrfs_ioctl_tree_search(file, argp);
2922 case BTRFS_IOC_INO_LOOKUP:
2923 return btrfs_ioctl_ino_lookup(file, argp);
2924 case BTRFS_IOC_SPACE_INFO:
2925 return btrfs_ioctl_space_info(root, argp);
2926 case BTRFS_IOC_SYNC:
2927 btrfs_sync_fs(file->f_dentry->d_sb, 1);
2928 return 0;
2929 case BTRFS_IOC_START_SYNC:
2930 return btrfs_ioctl_start_sync(file, argp);
2931 case BTRFS_IOC_WAIT_SYNC:
2932 return btrfs_ioctl_wait_sync(file, argp);
2933 case BTRFS_IOC_SCRUB:
2934 return btrfs_ioctl_scrub(root, argp);
2935 case BTRFS_IOC_SCRUB_CANCEL:
2936 return btrfs_ioctl_scrub_cancel(root, argp);
2937 case BTRFS_IOC_SCRUB_PROGRESS:
2938 return btrfs_ioctl_scrub_progress(root, argp);
2939 }
2940
2941 return -ENOTTY;
2942}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6#include <linux/kernel.h>
7#include <linux/bio.h>
8#include <linux/file.h>
9#include <linux/fs.h>
10#include <linux/fsnotify.h>
11#include <linux/pagemap.h>
12#include <linux/highmem.h>
13#include <linux/time.h>
14#include <linux/string.h>
15#include <linux/backing-dev.h>
16#include <linux/mount.h>
17#include <linux/namei.h>
18#include <linux/writeback.h>
19#include <linux/compat.h>
20#include <linux/security.h>
21#include <linux/xattr.h>
22#include <linux/mm.h>
23#include <linux/slab.h>
24#include <linux/blkdev.h>
25#include <linux/uuid.h>
26#include <linux/btrfs.h>
27#include <linux/uaccess.h>
28#include <linux/iversion.h>
29#include "ctree.h"
30#include "disk-io.h"
31#include "transaction.h"
32#include "btrfs_inode.h"
33#include "print-tree.h"
34#include "volumes.h"
35#include "locking.h"
36#include "inode-map.h"
37#include "backref.h"
38#include "rcu-string.h"
39#include "send.h"
40#include "dev-replace.h"
41#include "props.h"
42#include "sysfs.h"
43#include "qgroup.h"
44#include "tree-log.h"
45#include "compression.h"
46#include "space-info.h"
47#include "delalloc-space.h"
48#include "block-group.h"
49
50#ifdef CONFIG_64BIT
51/* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
52 * structures are incorrect, as the timespec structure from userspace
53 * is 4 bytes too small. We define these alternatives here to teach
54 * the kernel about the 32-bit struct packing.
55 */
56struct btrfs_ioctl_timespec_32 {
57 __u64 sec;
58 __u32 nsec;
59} __attribute__ ((__packed__));
60
61struct btrfs_ioctl_received_subvol_args_32 {
62 char uuid[BTRFS_UUID_SIZE]; /* in */
63 __u64 stransid; /* in */
64 __u64 rtransid; /* out */
65 struct btrfs_ioctl_timespec_32 stime; /* in */
66 struct btrfs_ioctl_timespec_32 rtime; /* out */
67 __u64 flags; /* in */
68 __u64 reserved[16]; /* in */
69} __attribute__ ((__packed__));
70
71#define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
72 struct btrfs_ioctl_received_subvol_args_32)
73#endif
74
75#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
76struct btrfs_ioctl_send_args_32 {
77 __s64 send_fd; /* in */
78 __u64 clone_sources_count; /* in */
79 compat_uptr_t clone_sources; /* in */
80 __u64 parent_root; /* in */
81 __u64 flags; /* in */
82 __u64 reserved[4]; /* in */
83} __attribute__ ((__packed__));
84
85#define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \
86 struct btrfs_ioctl_send_args_32)
87#endif
88
89static int btrfs_clone(struct inode *src, struct inode *inode,
90 u64 off, u64 olen, u64 olen_aligned, u64 destoff,
91 int no_time_update);
92
93/* Mask out flags that are inappropriate for the given type of inode. */
94static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,
95 unsigned int flags)
96{
97 if (S_ISDIR(inode->i_mode))
98 return flags;
99 else if (S_ISREG(inode->i_mode))
100 return flags & ~FS_DIRSYNC_FL;
101 else
102 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
103}
104
105/*
106 * Export internal inode flags to the format expected by the FS_IOC_GETFLAGS
107 * ioctl.
108 */
109static unsigned int btrfs_inode_flags_to_fsflags(unsigned int flags)
110{
111 unsigned int iflags = 0;
112
113 if (flags & BTRFS_INODE_SYNC)
114 iflags |= FS_SYNC_FL;
115 if (flags & BTRFS_INODE_IMMUTABLE)
116 iflags |= FS_IMMUTABLE_FL;
117 if (flags & BTRFS_INODE_APPEND)
118 iflags |= FS_APPEND_FL;
119 if (flags & BTRFS_INODE_NODUMP)
120 iflags |= FS_NODUMP_FL;
121 if (flags & BTRFS_INODE_NOATIME)
122 iflags |= FS_NOATIME_FL;
123 if (flags & BTRFS_INODE_DIRSYNC)
124 iflags |= FS_DIRSYNC_FL;
125 if (flags & BTRFS_INODE_NODATACOW)
126 iflags |= FS_NOCOW_FL;
127
128 if (flags & BTRFS_INODE_NOCOMPRESS)
129 iflags |= FS_NOCOMP_FL;
130 else if (flags & BTRFS_INODE_COMPRESS)
131 iflags |= FS_COMPR_FL;
132
133 return iflags;
134}
135
136/*
137 * Update inode->i_flags based on the btrfs internal flags.
138 */
139void btrfs_sync_inode_flags_to_i_flags(struct inode *inode)
140{
141 struct btrfs_inode *binode = BTRFS_I(inode);
142 unsigned int new_fl = 0;
143
144 if (binode->flags & BTRFS_INODE_SYNC)
145 new_fl |= S_SYNC;
146 if (binode->flags & BTRFS_INODE_IMMUTABLE)
147 new_fl |= S_IMMUTABLE;
148 if (binode->flags & BTRFS_INODE_APPEND)
149 new_fl |= S_APPEND;
150 if (binode->flags & BTRFS_INODE_NOATIME)
151 new_fl |= S_NOATIME;
152 if (binode->flags & BTRFS_INODE_DIRSYNC)
153 new_fl |= S_DIRSYNC;
154
155 set_mask_bits(&inode->i_flags,
156 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
157 new_fl);
158}
159
160static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
161{
162 struct btrfs_inode *binode = BTRFS_I(file_inode(file));
163 unsigned int flags = btrfs_inode_flags_to_fsflags(binode->flags);
164
165 if (copy_to_user(arg, &flags, sizeof(flags)))
166 return -EFAULT;
167 return 0;
168}
169
170/* Check if @flags are a supported and valid set of FS_*_FL flags */
171static int check_fsflags(unsigned int flags)
172{
173 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
174 FS_NOATIME_FL | FS_NODUMP_FL | \
175 FS_SYNC_FL | FS_DIRSYNC_FL | \
176 FS_NOCOMP_FL | FS_COMPR_FL |
177 FS_NOCOW_FL))
178 return -EOPNOTSUPP;
179
180 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
181 return -EINVAL;
182
183 return 0;
184}
185
186static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
187{
188 struct inode *inode = file_inode(file);
189 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
190 struct btrfs_inode *binode = BTRFS_I(inode);
191 struct btrfs_root *root = binode->root;
192 struct btrfs_trans_handle *trans;
193 unsigned int fsflags, old_fsflags;
194 int ret;
195 const char *comp = NULL;
196 u32 binode_flags = binode->flags;
197
198 if (!inode_owner_or_capable(inode))
199 return -EPERM;
200
201 if (btrfs_root_readonly(root))
202 return -EROFS;
203
204 if (copy_from_user(&fsflags, arg, sizeof(fsflags)))
205 return -EFAULT;
206
207 ret = check_fsflags(fsflags);
208 if (ret)
209 return ret;
210
211 ret = mnt_want_write_file(file);
212 if (ret)
213 return ret;
214
215 inode_lock(inode);
216
217 fsflags = btrfs_mask_fsflags_for_type(inode, fsflags);
218 old_fsflags = btrfs_inode_flags_to_fsflags(binode->flags);
219 ret = vfs_ioc_setflags_prepare(inode, old_fsflags, fsflags);
220 if (ret)
221 goto out_unlock;
222
223 if (fsflags & FS_SYNC_FL)
224 binode_flags |= BTRFS_INODE_SYNC;
225 else
226 binode_flags &= ~BTRFS_INODE_SYNC;
227 if (fsflags & FS_IMMUTABLE_FL)
228 binode_flags |= BTRFS_INODE_IMMUTABLE;
229 else
230 binode_flags &= ~BTRFS_INODE_IMMUTABLE;
231 if (fsflags & FS_APPEND_FL)
232 binode_flags |= BTRFS_INODE_APPEND;
233 else
234 binode_flags &= ~BTRFS_INODE_APPEND;
235 if (fsflags & FS_NODUMP_FL)
236 binode_flags |= BTRFS_INODE_NODUMP;
237 else
238 binode_flags &= ~BTRFS_INODE_NODUMP;
239 if (fsflags & FS_NOATIME_FL)
240 binode_flags |= BTRFS_INODE_NOATIME;
241 else
242 binode_flags &= ~BTRFS_INODE_NOATIME;
243 if (fsflags & FS_DIRSYNC_FL)
244 binode_flags |= BTRFS_INODE_DIRSYNC;
245 else
246 binode_flags &= ~BTRFS_INODE_DIRSYNC;
247 if (fsflags & FS_NOCOW_FL) {
248 if (S_ISREG(inode->i_mode)) {
249 /*
250 * It's safe to turn csums off here, no extents exist.
251 * Otherwise we want the flag to reflect the real COW
252 * status of the file and will not set it.
253 */
254 if (inode->i_size == 0)
255 binode_flags |= BTRFS_INODE_NODATACOW |
256 BTRFS_INODE_NODATASUM;
257 } else {
258 binode_flags |= BTRFS_INODE_NODATACOW;
259 }
260 } else {
261 /*
262 * Revert back under same assumptions as above
263 */
264 if (S_ISREG(inode->i_mode)) {
265 if (inode->i_size == 0)
266 binode_flags &= ~(BTRFS_INODE_NODATACOW |
267 BTRFS_INODE_NODATASUM);
268 } else {
269 binode_flags &= ~BTRFS_INODE_NODATACOW;
270 }
271 }
272
273 /*
274 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
275 * flag may be changed automatically if compression code won't make
276 * things smaller.
277 */
278 if (fsflags & FS_NOCOMP_FL) {
279 binode_flags &= ~BTRFS_INODE_COMPRESS;
280 binode_flags |= BTRFS_INODE_NOCOMPRESS;
281 } else if (fsflags & FS_COMPR_FL) {
282
283 if (IS_SWAPFILE(inode)) {
284 ret = -ETXTBSY;
285 goto out_unlock;
286 }
287
288 binode_flags |= BTRFS_INODE_COMPRESS;
289 binode_flags &= ~BTRFS_INODE_NOCOMPRESS;
290
291 comp = btrfs_compress_type2str(fs_info->compress_type);
292 if (!comp || comp[0] == 0)
293 comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);
294 } else {
295 binode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
296 }
297
298 /*
299 * 1 for inode item
300 * 2 for properties
301 */
302 trans = btrfs_start_transaction(root, 3);
303 if (IS_ERR(trans)) {
304 ret = PTR_ERR(trans);
305 goto out_unlock;
306 }
307
308 if (comp) {
309 ret = btrfs_set_prop(trans, inode, "btrfs.compression", comp,
310 strlen(comp), 0);
311 if (ret) {
312 btrfs_abort_transaction(trans, ret);
313 goto out_end_trans;
314 }
315 } else {
316 ret = btrfs_set_prop(trans, inode, "btrfs.compression", NULL,
317 0, 0);
318 if (ret && ret != -ENODATA) {
319 btrfs_abort_transaction(trans, ret);
320 goto out_end_trans;
321 }
322 }
323
324 binode->flags = binode_flags;
325 btrfs_sync_inode_flags_to_i_flags(inode);
326 inode_inc_iversion(inode);
327 inode->i_ctime = current_time(inode);
328 ret = btrfs_update_inode(trans, root, inode);
329
330 out_end_trans:
331 btrfs_end_transaction(trans);
332 out_unlock:
333 inode_unlock(inode);
334 mnt_drop_write_file(file);
335 return ret;
336}
337
338/*
339 * Translate btrfs internal inode flags to xflags as expected by the
340 * FS_IOC_FSGETXATT ioctl. Filter only the supported ones, unknown flags are
341 * silently dropped.
342 */
343static unsigned int btrfs_inode_flags_to_xflags(unsigned int flags)
344{
345 unsigned int xflags = 0;
346
347 if (flags & BTRFS_INODE_APPEND)
348 xflags |= FS_XFLAG_APPEND;
349 if (flags & BTRFS_INODE_IMMUTABLE)
350 xflags |= FS_XFLAG_IMMUTABLE;
351 if (flags & BTRFS_INODE_NOATIME)
352 xflags |= FS_XFLAG_NOATIME;
353 if (flags & BTRFS_INODE_NODUMP)
354 xflags |= FS_XFLAG_NODUMP;
355 if (flags & BTRFS_INODE_SYNC)
356 xflags |= FS_XFLAG_SYNC;
357
358 return xflags;
359}
360
361/* Check if @flags are a supported and valid set of FS_XFLAGS_* flags */
362static int check_xflags(unsigned int flags)
363{
364 if (flags & ~(FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE | FS_XFLAG_NOATIME |
365 FS_XFLAG_NODUMP | FS_XFLAG_SYNC))
366 return -EOPNOTSUPP;
367 return 0;
368}
369
370/*
371 * Set the xflags from the internal inode flags. The remaining items of fsxattr
372 * are zeroed.
373 */
374static int btrfs_ioctl_fsgetxattr(struct file *file, void __user *arg)
375{
376 struct btrfs_inode *binode = BTRFS_I(file_inode(file));
377 struct fsxattr fa;
378
379 simple_fill_fsxattr(&fa, btrfs_inode_flags_to_xflags(binode->flags));
380 if (copy_to_user(arg, &fa, sizeof(fa)))
381 return -EFAULT;
382
383 return 0;
384}
385
386static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg)
387{
388 struct inode *inode = file_inode(file);
389 struct btrfs_inode *binode = BTRFS_I(inode);
390 struct btrfs_root *root = binode->root;
391 struct btrfs_trans_handle *trans;
392 struct fsxattr fa, old_fa;
393 unsigned old_flags;
394 unsigned old_i_flags;
395 int ret = 0;
396
397 if (!inode_owner_or_capable(inode))
398 return -EPERM;
399
400 if (btrfs_root_readonly(root))
401 return -EROFS;
402
403 if (copy_from_user(&fa, arg, sizeof(fa)))
404 return -EFAULT;
405
406 ret = check_xflags(fa.fsx_xflags);
407 if (ret)
408 return ret;
409
410 if (fa.fsx_extsize != 0 || fa.fsx_projid != 0 || fa.fsx_cowextsize != 0)
411 return -EOPNOTSUPP;
412
413 ret = mnt_want_write_file(file);
414 if (ret)
415 return ret;
416
417 inode_lock(inode);
418
419 old_flags = binode->flags;
420 old_i_flags = inode->i_flags;
421
422 simple_fill_fsxattr(&old_fa,
423 btrfs_inode_flags_to_xflags(binode->flags));
424 ret = vfs_ioc_fssetxattr_check(inode, &old_fa, &fa);
425 if (ret)
426 goto out_unlock;
427
428 if (fa.fsx_xflags & FS_XFLAG_SYNC)
429 binode->flags |= BTRFS_INODE_SYNC;
430 else
431 binode->flags &= ~BTRFS_INODE_SYNC;
432 if (fa.fsx_xflags & FS_XFLAG_IMMUTABLE)
433 binode->flags |= BTRFS_INODE_IMMUTABLE;
434 else
435 binode->flags &= ~BTRFS_INODE_IMMUTABLE;
436 if (fa.fsx_xflags & FS_XFLAG_APPEND)
437 binode->flags |= BTRFS_INODE_APPEND;
438 else
439 binode->flags &= ~BTRFS_INODE_APPEND;
440 if (fa.fsx_xflags & FS_XFLAG_NODUMP)
441 binode->flags |= BTRFS_INODE_NODUMP;
442 else
443 binode->flags &= ~BTRFS_INODE_NODUMP;
444 if (fa.fsx_xflags & FS_XFLAG_NOATIME)
445 binode->flags |= BTRFS_INODE_NOATIME;
446 else
447 binode->flags &= ~BTRFS_INODE_NOATIME;
448
449 /* 1 item for the inode */
450 trans = btrfs_start_transaction(root, 1);
451 if (IS_ERR(trans)) {
452 ret = PTR_ERR(trans);
453 goto out_unlock;
454 }
455
456 btrfs_sync_inode_flags_to_i_flags(inode);
457 inode_inc_iversion(inode);
458 inode->i_ctime = current_time(inode);
459 ret = btrfs_update_inode(trans, root, inode);
460
461 btrfs_end_transaction(trans);
462
463out_unlock:
464 if (ret) {
465 binode->flags = old_flags;
466 inode->i_flags = old_i_flags;
467 }
468
469 inode_unlock(inode);
470 mnt_drop_write_file(file);
471
472 return ret;
473}
474
475static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
476{
477 struct inode *inode = file_inode(file);
478
479 return put_user(inode->i_generation, arg);
480}
481
482static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
483{
484 struct inode *inode = file_inode(file);
485 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
486 struct btrfs_device *device;
487 struct request_queue *q;
488 struct fstrim_range range;
489 u64 minlen = ULLONG_MAX;
490 u64 num_devices = 0;
491 int ret;
492
493 if (!capable(CAP_SYS_ADMIN))
494 return -EPERM;
495
496 /*
497 * If the fs is mounted with nologreplay, which requires it to be
498 * mounted in RO mode as well, we can not allow discard on free space
499 * inside block groups, because log trees refer to extents that are not
500 * pinned in a block group's free space cache (pinning the extents is
501 * precisely the first phase of replaying a log tree).
502 */
503 if (btrfs_test_opt(fs_info, NOLOGREPLAY))
504 return -EROFS;
505
506 rcu_read_lock();
507 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
508 dev_list) {
509 if (!device->bdev)
510 continue;
511 q = bdev_get_queue(device->bdev);
512 if (blk_queue_discard(q)) {
513 num_devices++;
514 minlen = min_t(u64, q->limits.discard_granularity,
515 minlen);
516 }
517 }
518 rcu_read_unlock();
519
520 if (!num_devices)
521 return -EOPNOTSUPP;
522 if (copy_from_user(&range, arg, sizeof(range)))
523 return -EFAULT;
524
525 /*
526 * NOTE: Don't truncate the range using super->total_bytes. Bytenr of
527 * block group is in the logical address space, which can be any
528 * sectorsize aligned bytenr in the range [0, U64_MAX].
529 */
530 if (range.len < fs_info->sb->s_blocksize)
531 return -EINVAL;
532
533 range.minlen = max(range.minlen, minlen);
534 ret = btrfs_trim_fs(fs_info, &range);
535 if (ret < 0)
536 return ret;
537
538 if (copy_to_user(arg, &range, sizeof(range)))
539 return -EFAULT;
540
541 return 0;
542}
543
544int btrfs_is_empty_uuid(u8 *uuid)
545{
546 int i;
547
548 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
549 if (uuid[i])
550 return 0;
551 }
552 return 1;
553}
554
555static noinline int create_subvol(struct inode *dir,
556 struct dentry *dentry,
557 const char *name, int namelen,
558 u64 *async_transid,
559 struct btrfs_qgroup_inherit *inherit)
560{
561 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
562 struct btrfs_trans_handle *trans;
563 struct btrfs_key key;
564 struct btrfs_root_item *root_item;
565 struct btrfs_inode_item *inode_item;
566 struct extent_buffer *leaf;
567 struct btrfs_root *root = BTRFS_I(dir)->root;
568 struct btrfs_root *new_root;
569 struct btrfs_block_rsv block_rsv;
570 struct timespec64 cur_time = current_time(dir);
571 struct inode *inode;
572 int ret;
573 int err;
574 u64 objectid;
575 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
576 u64 index = 0;
577 uuid_le new_uuid;
578
579 root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
580 if (!root_item)
581 return -ENOMEM;
582
583 ret = btrfs_find_free_objectid(fs_info->tree_root, &objectid);
584 if (ret)
585 goto fail_free;
586
587 /*
588 * Don't create subvolume whose level is not zero. Or qgroup will be
589 * screwed up since it assumes subvolume qgroup's level to be 0.
590 */
591 if (btrfs_qgroup_level(objectid)) {
592 ret = -ENOSPC;
593 goto fail_free;
594 }
595
596 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
597 /*
598 * The same as the snapshot creation, please see the comment
599 * of create_snapshot().
600 */
601 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 8, false);
602 if (ret)
603 goto fail_free;
604
605 trans = btrfs_start_transaction(root, 0);
606 if (IS_ERR(trans)) {
607 ret = PTR_ERR(trans);
608 btrfs_subvolume_release_metadata(fs_info, &block_rsv);
609 goto fail_free;
610 }
611 trans->block_rsv = &block_rsv;
612 trans->bytes_reserved = block_rsv.size;
613
614 ret = btrfs_qgroup_inherit(trans, 0, objectid, inherit);
615 if (ret)
616 goto fail;
617
618 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
619 if (IS_ERR(leaf)) {
620 ret = PTR_ERR(leaf);
621 goto fail;
622 }
623
624 btrfs_mark_buffer_dirty(leaf);
625
626 inode_item = &root_item->inode;
627 btrfs_set_stack_inode_generation(inode_item, 1);
628 btrfs_set_stack_inode_size(inode_item, 3);
629 btrfs_set_stack_inode_nlink(inode_item, 1);
630 btrfs_set_stack_inode_nbytes(inode_item,
631 fs_info->nodesize);
632 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
633
634 btrfs_set_root_flags(root_item, 0);
635 btrfs_set_root_limit(root_item, 0);
636 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
637
638 btrfs_set_root_bytenr(root_item, leaf->start);
639 btrfs_set_root_generation(root_item, trans->transid);
640 btrfs_set_root_level(root_item, 0);
641 btrfs_set_root_refs(root_item, 1);
642 btrfs_set_root_used(root_item, leaf->len);
643 btrfs_set_root_last_snapshot(root_item, 0);
644
645 btrfs_set_root_generation_v2(root_item,
646 btrfs_root_generation(root_item));
647 uuid_le_gen(&new_uuid);
648 memcpy(root_item->uuid, new_uuid.b, BTRFS_UUID_SIZE);
649 btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);
650 btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);
651 root_item->ctime = root_item->otime;
652 btrfs_set_root_ctransid(root_item, trans->transid);
653 btrfs_set_root_otransid(root_item, trans->transid);
654
655 btrfs_tree_unlock(leaf);
656 free_extent_buffer(leaf);
657 leaf = NULL;
658
659 btrfs_set_root_dirid(root_item, new_dirid);
660
661 key.objectid = objectid;
662 key.offset = 0;
663 key.type = BTRFS_ROOT_ITEM_KEY;
664 ret = btrfs_insert_root(trans, fs_info->tree_root, &key,
665 root_item);
666 if (ret)
667 goto fail;
668
669 key.offset = (u64)-1;
670 new_root = btrfs_read_fs_root_no_name(fs_info, &key);
671 if (IS_ERR(new_root)) {
672 ret = PTR_ERR(new_root);
673 btrfs_abort_transaction(trans, ret);
674 goto fail;
675 }
676
677 btrfs_record_root_in_trans(trans, new_root);
678
679 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
680 if (ret) {
681 /* We potentially lose an unused inode item here */
682 btrfs_abort_transaction(trans, ret);
683 goto fail;
684 }
685
686 mutex_lock(&new_root->objectid_mutex);
687 new_root->highest_objectid = new_dirid;
688 mutex_unlock(&new_root->objectid_mutex);
689
690 /*
691 * insert the directory item
692 */
693 ret = btrfs_set_inode_index(BTRFS_I(dir), &index);
694 if (ret) {
695 btrfs_abort_transaction(trans, ret);
696 goto fail;
697 }
698
699 ret = btrfs_insert_dir_item(trans, name, namelen, BTRFS_I(dir), &key,
700 BTRFS_FT_DIR, index);
701 if (ret) {
702 btrfs_abort_transaction(trans, ret);
703 goto fail;
704 }
705
706 btrfs_i_size_write(BTRFS_I(dir), dir->i_size + namelen * 2);
707 ret = btrfs_update_inode(trans, root, dir);
708 BUG_ON(ret);
709
710 ret = btrfs_add_root_ref(trans, objectid, root->root_key.objectid,
711 btrfs_ino(BTRFS_I(dir)), index, name, namelen);
712 BUG_ON(ret);
713
714 ret = btrfs_uuid_tree_add(trans, root_item->uuid,
715 BTRFS_UUID_KEY_SUBVOL, objectid);
716 if (ret)
717 btrfs_abort_transaction(trans, ret);
718
719fail:
720 kfree(root_item);
721 trans->block_rsv = NULL;
722 trans->bytes_reserved = 0;
723 btrfs_subvolume_release_metadata(fs_info, &block_rsv);
724
725 if (async_transid) {
726 *async_transid = trans->transid;
727 err = btrfs_commit_transaction_async(trans, 1);
728 if (err)
729 err = btrfs_commit_transaction(trans);
730 } else {
731 err = btrfs_commit_transaction(trans);
732 }
733 if (err && !ret)
734 ret = err;
735
736 if (!ret) {
737 inode = btrfs_lookup_dentry(dir, dentry);
738 if (IS_ERR(inode))
739 return PTR_ERR(inode);
740 d_instantiate(dentry, inode);
741 }
742 return ret;
743
744fail_free:
745 kfree(root_item);
746 return ret;
747}
748
749static int create_snapshot(struct btrfs_root *root, struct inode *dir,
750 struct dentry *dentry,
751 u64 *async_transid, bool readonly,
752 struct btrfs_qgroup_inherit *inherit)
753{
754 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
755 struct inode *inode;
756 struct btrfs_pending_snapshot *pending_snapshot;
757 struct btrfs_trans_handle *trans;
758 int ret;
759 bool snapshot_force_cow = false;
760
761 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
762 return -EINVAL;
763
764 if (atomic_read(&root->nr_swapfiles)) {
765 btrfs_warn(fs_info,
766 "cannot snapshot subvolume with active swapfile");
767 return -ETXTBSY;
768 }
769
770 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL);
771 if (!pending_snapshot)
772 return -ENOMEM;
773
774 pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
775 GFP_KERNEL);
776 pending_snapshot->path = btrfs_alloc_path();
777 if (!pending_snapshot->root_item || !pending_snapshot->path) {
778 ret = -ENOMEM;
779 goto free_pending;
780 }
781
782 /*
783 * Force new buffered writes to reserve space even when NOCOW is
784 * possible. This is to avoid later writeback (running dealloc) to
785 * fallback to COW mode and unexpectedly fail with ENOSPC.
786 */
787 atomic_inc(&root->will_be_snapshotted);
788 smp_mb__after_atomic();
789 /* wait for no snapshot writes */
790 wait_event(root->subv_writers->wait,
791 percpu_counter_sum(&root->subv_writers->counter) == 0);
792
793 ret = btrfs_start_delalloc_snapshot(root);
794 if (ret)
795 goto dec_and_free;
796
797 /*
798 * All previous writes have started writeback in NOCOW mode, so now
799 * we force future writes to fallback to COW mode during snapshot
800 * creation.
801 */
802 atomic_inc(&root->snapshot_force_cow);
803 snapshot_force_cow = true;
804
805 btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
806
807 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
808 BTRFS_BLOCK_RSV_TEMP);
809 /*
810 * 1 - parent dir inode
811 * 2 - dir entries
812 * 1 - root item
813 * 2 - root ref/backref
814 * 1 - root of snapshot
815 * 1 - UUID item
816 */
817 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
818 &pending_snapshot->block_rsv, 8,
819 false);
820 if (ret)
821 goto dec_and_free;
822
823 pending_snapshot->dentry = dentry;
824 pending_snapshot->root = root;
825 pending_snapshot->readonly = readonly;
826 pending_snapshot->dir = dir;
827 pending_snapshot->inherit = inherit;
828
829 trans = btrfs_start_transaction(root, 0);
830 if (IS_ERR(trans)) {
831 ret = PTR_ERR(trans);
832 goto fail;
833 }
834
835 spin_lock(&fs_info->trans_lock);
836 list_add(&pending_snapshot->list,
837 &trans->transaction->pending_snapshots);
838 spin_unlock(&fs_info->trans_lock);
839 if (async_transid) {
840 *async_transid = trans->transid;
841 ret = btrfs_commit_transaction_async(trans, 1);
842 if (ret)
843 ret = btrfs_commit_transaction(trans);
844 } else {
845 ret = btrfs_commit_transaction(trans);
846 }
847 if (ret)
848 goto fail;
849
850 ret = pending_snapshot->error;
851 if (ret)
852 goto fail;
853
854 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
855 if (ret)
856 goto fail;
857
858 inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
859 if (IS_ERR(inode)) {
860 ret = PTR_ERR(inode);
861 goto fail;
862 }
863
864 d_instantiate(dentry, inode);
865 ret = 0;
866fail:
867 btrfs_subvolume_release_metadata(fs_info, &pending_snapshot->block_rsv);
868dec_and_free:
869 if (snapshot_force_cow)
870 atomic_dec(&root->snapshot_force_cow);
871 if (atomic_dec_and_test(&root->will_be_snapshotted))
872 wake_up_var(&root->will_be_snapshotted);
873free_pending:
874 kfree(pending_snapshot->root_item);
875 btrfs_free_path(pending_snapshot->path);
876 kfree(pending_snapshot);
877
878 return ret;
879}
880
881/* copy of may_delete in fs/namei.c()
882 * Check whether we can remove a link victim from directory dir, check
883 * whether the type of victim is right.
884 * 1. We can't do it if dir is read-only (done in permission())
885 * 2. We should have write and exec permissions on dir
886 * 3. We can't remove anything from append-only dir
887 * 4. We can't do anything with immutable dir (done in permission())
888 * 5. If the sticky bit on dir is set we should either
889 * a. be owner of dir, or
890 * b. be owner of victim, or
891 * c. have CAP_FOWNER capability
892 * 6. If the victim is append-only or immutable we can't do anything with
893 * links pointing to it.
894 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
895 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
896 * 9. We can't remove a root or mountpoint.
897 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
898 * nfs_async_unlink().
899 */
900
901static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
902{
903 int error;
904
905 if (d_really_is_negative(victim))
906 return -ENOENT;
907
908 BUG_ON(d_inode(victim->d_parent) != dir);
909 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
910
911 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
912 if (error)
913 return error;
914 if (IS_APPEND(dir))
915 return -EPERM;
916 if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
917 IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
918 return -EPERM;
919 if (isdir) {
920 if (!d_is_dir(victim))
921 return -ENOTDIR;
922 if (IS_ROOT(victim))
923 return -EBUSY;
924 } else if (d_is_dir(victim))
925 return -EISDIR;
926 if (IS_DEADDIR(dir))
927 return -ENOENT;
928 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
929 return -EBUSY;
930 return 0;
931}
932
933/* copy of may_create in fs/namei.c() */
934static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
935{
936 if (d_really_is_positive(child))
937 return -EEXIST;
938 if (IS_DEADDIR(dir))
939 return -ENOENT;
940 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
941}
942
943/*
944 * Create a new subvolume below @parent. This is largely modeled after
945 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
946 * inside this filesystem so it's quite a bit simpler.
947 */
948static noinline int btrfs_mksubvol(const struct path *parent,
949 const char *name, int namelen,
950 struct btrfs_root *snap_src,
951 u64 *async_transid, bool readonly,
952 struct btrfs_qgroup_inherit *inherit)
953{
954 struct inode *dir = d_inode(parent->dentry);
955 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
956 struct dentry *dentry;
957 int error;
958
959 error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
960 if (error == -EINTR)
961 return error;
962
963 dentry = lookup_one_len(name, parent->dentry, namelen);
964 error = PTR_ERR(dentry);
965 if (IS_ERR(dentry))
966 goto out_unlock;
967
968 error = btrfs_may_create(dir, dentry);
969 if (error)
970 goto out_dput;
971
972 /*
973 * even if this name doesn't exist, we may get hash collisions.
974 * check for them now when we can safely fail
975 */
976 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
977 dir->i_ino, name,
978 namelen);
979 if (error)
980 goto out_dput;
981
982 down_read(&fs_info->subvol_sem);
983
984 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
985 goto out_up_read;
986
987 if (snap_src) {
988 error = create_snapshot(snap_src, dir, dentry,
989 async_transid, readonly, inherit);
990 } else {
991 error = create_subvol(dir, dentry, name, namelen,
992 async_transid, inherit);
993 }
994 if (!error)
995 fsnotify_mkdir(dir, dentry);
996out_up_read:
997 up_read(&fs_info->subvol_sem);
998out_dput:
999 dput(dentry);
1000out_unlock:
1001 inode_unlock(dir);
1002 return error;
1003}
1004
1005/*
1006 * When we're defragging a range, we don't want to kick it off again
1007 * if it is really just waiting for delalloc to send it down.
1008 * If we find a nice big extent or delalloc range for the bytes in the
1009 * file you want to defrag, we return 0 to let you know to skip this
1010 * part of the file
1011 */
1012static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
1013{
1014 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1015 struct extent_map *em = NULL;
1016 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1017 u64 end;
1018
1019 read_lock(&em_tree->lock);
1020 em = lookup_extent_mapping(em_tree, offset, PAGE_SIZE);
1021 read_unlock(&em_tree->lock);
1022
1023 if (em) {
1024 end = extent_map_end(em);
1025 free_extent_map(em);
1026 if (end - offset > thresh)
1027 return 0;
1028 }
1029 /* if we already have a nice delalloc here, just stop */
1030 thresh /= 2;
1031 end = count_range_bits(io_tree, &offset, offset + thresh,
1032 thresh, EXTENT_DELALLOC, 1);
1033 if (end >= thresh)
1034 return 0;
1035 return 1;
1036}
1037
1038/*
1039 * helper function to walk through a file and find extents
1040 * newer than a specific transid, and smaller than thresh.
1041 *
1042 * This is used by the defragging code to find new and small
1043 * extents
1044 */
1045static int find_new_extents(struct btrfs_root *root,
1046 struct inode *inode, u64 newer_than,
1047 u64 *off, u32 thresh)
1048{
1049 struct btrfs_path *path;
1050 struct btrfs_key min_key;
1051 struct extent_buffer *leaf;
1052 struct btrfs_file_extent_item *extent;
1053 int type;
1054 int ret;
1055 u64 ino = btrfs_ino(BTRFS_I(inode));
1056
1057 path = btrfs_alloc_path();
1058 if (!path)
1059 return -ENOMEM;
1060
1061 min_key.objectid = ino;
1062 min_key.type = BTRFS_EXTENT_DATA_KEY;
1063 min_key.offset = *off;
1064
1065 while (1) {
1066 ret = btrfs_search_forward(root, &min_key, path, newer_than);
1067 if (ret != 0)
1068 goto none;
1069process_slot:
1070 if (min_key.objectid != ino)
1071 goto none;
1072 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
1073 goto none;
1074
1075 leaf = path->nodes[0];
1076 extent = btrfs_item_ptr(leaf, path->slots[0],
1077 struct btrfs_file_extent_item);
1078
1079 type = btrfs_file_extent_type(leaf, extent);
1080 if (type == BTRFS_FILE_EXTENT_REG &&
1081 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
1082 check_defrag_in_cache(inode, min_key.offset, thresh)) {
1083 *off = min_key.offset;
1084 btrfs_free_path(path);
1085 return 0;
1086 }
1087
1088 path->slots[0]++;
1089 if (path->slots[0] < btrfs_header_nritems(leaf)) {
1090 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
1091 goto process_slot;
1092 }
1093
1094 if (min_key.offset == (u64)-1)
1095 goto none;
1096
1097 min_key.offset++;
1098 btrfs_release_path(path);
1099 }
1100none:
1101 btrfs_free_path(path);
1102 return -ENOENT;
1103}
1104
1105static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
1106{
1107 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1108 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1109 struct extent_map *em;
1110 u64 len = PAGE_SIZE;
1111
1112 /*
1113 * hopefully we have this extent in the tree already, try without
1114 * the full extent lock
1115 */
1116 read_lock(&em_tree->lock);
1117 em = lookup_extent_mapping(em_tree, start, len);
1118 read_unlock(&em_tree->lock);
1119
1120 if (!em) {
1121 struct extent_state *cached = NULL;
1122 u64 end = start + len - 1;
1123
1124 /* get the big lock and read metadata off disk */
1125 lock_extent_bits(io_tree, start, end, &cached);
1126 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len, 0);
1127 unlock_extent_cached(io_tree, start, end, &cached);
1128
1129 if (IS_ERR(em))
1130 return NULL;
1131 }
1132
1133 return em;
1134}
1135
1136static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1137{
1138 struct extent_map *next;
1139 bool ret = true;
1140
1141 /* this is the last extent */
1142 if (em->start + em->len >= i_size_read(inode))
1143 return false;
1144
1145 next = defrag_lookup_extent(inode, em->start + em->len);
1146 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1147 ret = false;
1148 else if ((em->block_start + em->block_len == next->block_start) &&
1149 (em->block_len > SZ_128K && next->block_len > SZ_128K))
1150 ret = false;
1151
1152 free_extent_map(next);
1153 return ret;
1154}
1155
1156static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1157 u64 *last_len, u64 *skip, u64 *defrag_end,
1158 int compress)
1159{
1160 struct extent_map *em;
1161 int ret = 1;
1162 bool next_mergeable = true;
1163 bool prev_mergeable = true;
1164
1165 /*
1166 * make sure that once we start defragging an extent, we keep on
1167 * defragging it
1168 */
1169 if (start < *defrag_end)
1170 return 1;
1171
1172 *skip = 0;
1173
1174 em = defrag_lookup_extent(inode, start);
1175 if (!em)
1176 return 0;
1177
1178 /* this will cover holes, and inline extents */
1179 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1180 ret = 0;
1181 goto out;
1182 }
1183
1184 if (!*defrag_end)
1185 prev_mergeable = false;
1186
1187 next_mergeable = defrag_check_next_extent(inode, em);
1188 /*
1189 * we hit a real extent, if it is big or the next extent is not a
1190 * real extent, don't bother defragging it
1191 */
1192 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1193 (em->len >= thresh || (!next_mergeable && !prev_mergeable)))
1194 ret = 0;
1195out:
1196 /*
1197 * last_len ends up being a counter of how many bytes we've defragged.
1198 * every time we choose not to defrag an extent, we reset *last_len
1199 * so that the next tiny extent will force a defrag.
1200 *
1201 * The end result of this is that tiny extents before a single big
1202 * extent will force at least part of that big extent to be defragged.
1203 */
1204 if (ret) {
1205 *defrag_end = extent_map_end(em);
1206 } else {
1207 *last_len = 0;
1208 *skip = extent_map_end(em);
1209 *defrag_end = 0;
1210 }
1211
1212 free_extent_map(em);
1213 return ret;
1214}
1215
1216/*
1217 * it doesn't do much good to defrag one or two pages
1218 * at a time. This pulls in a nice chunk of pages
1219 * to COW and defrag.
1220 *
1221 * It also makes sure the delalloc code has enough
1222 * dirty data to avoid making new small extents as part
1223 * of the defrag
1224 *
1225 * It's a good idea to start RA on this range
1226 * before calling this.
1227 */
1228static int cluster_pages_for_defrag(struct inode *inode,
1229 struct page **pages,
1230 unsigned long start_index,
1231 unsigned long num_pages)
1232{
1233 unsigned long file_end;
1234 u64 isize = i_size_read(inode);
1235 u64 page_start;
1236 u64 page_end;
1237 u64 page_cnt;
1238 int ret;
1239 int i;
1240 int i_done;
1241 struct btrfs_ordered_extent *ordered;
1242 struct extent_state *cached_state = NULL;
1243 struct extent_io_tree *tree;
1244 struct extent_changeset *data_reserved = NULL;
1245 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1246
1247 file_end = (isize - 1) >> PAGE_SHIFT;
1248 if (!isize || start_index > file_end)
1249 return 0;
1250
1251 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1252
1253 ret = btrfs_delalloc_reserve_space(inode, &data_reserved,
1254 start_index << PAGE_SHIFT,
1255 page_cnt << PAGE_SHIFT);
1256 if (ret)
1257 return ret;
1258 i_done = 0;
1259 tree = &BTRFS_I(inode)->io_tree;
1260
1261 /* step one, lock all the pages */
1262 for (i = 0; i < page_cnt; i++) {
1263 struct page *page;
1264again:
1265 page = find_or_create_page(inode->i_mapping,
1266 start_index + i, mask);
1267 if (!page)
1268 break;
1269
1270 page_start = page_offset(page);
1271 page_end = page_start + PAGE_SIZE - 1;
1272 while (1) {
1273 lock_extent_bits(tree, page_start, page_end,
1274 &cached_state);
1275 ordered = btrfs_lookup_ordered_extent(inode,
1276 page_start);
1277 unlock_extent_cached(tree, page_start, page_end,
1278 &cached_state);
1279 if (!ordered)
1280 break;
1281
1282 unlock_page(page);
1283 btrfs_start_ordered_extent(inode, ordered, 1);
1284 btrfs_put_ordered_extent(ordered);
1285 lock_page(page);
1286 /*
1287 * we unlocked the page above, so we need check if
1288 * it was released or not.
1289 */
1290 if (page->mapping != inode->i_mapping) {
1291 unlock_page(page);
1292 put_page(page);
1293 goto again;
1294 }
1295 }
1296
1297 if (!PageUptodate(page)) {
1298 btrfs_readpage(NULL, page);
1299 lock_page(page);
1300 if (!PageUptodate(page)) {
1301 unlock_page(page);
1302 put_page(page);
1303 ret = -EIO;
1304 break;
1305 }
1306 }
1307
1308 if (page->mapping != inode->i_mapping) {
1309 unlock_page(page);
1310 put_page(page);
1311 goto again;
1312 }
1313
1314 pages[i] = page;
1315 i_done++;
1316 }
1317 if (!i_done || ret)
1318 goto out;
1319
1320 if (!(inode->i_sb->s_flags & SB_ACTIVE))
1321 goto out;
1322
1323 /*
1324 * so now we have a nice long stream of locked
1325 * and up to date pages, lets wait on them
1326 */
1327 for (i = 0; i < i_done; i++)
1328 wait_on_page_writeback(pages[i]);
1329
1330 page_start = page_offset(pages[0]);
1331 page_end = page_offset(pages[i_done - 1]) + PAGE_SIZE;
1332
1333 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1334 page_start, page_end - 1, &cached_state);
1335 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1336 page_end - 1, EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |
1337 EXTENT_DEFRAG, 0, 0, &cached_state);
1338
1339 if (i_done != page_cnt) {
1340 spin_lock(&BTRFS_I(inode)->lock);
1341 btrfs_mod_outstanding_extents(BTRFS_I(inode), 1);
1342 spin_unlock(&BTRFS_I(inode)->lock);
1343 btrfs_delalloc_release_space(inode, data_reserved,
1344 start_index << PAGE_SHIFT,
1345 (page_cnt - i_done) << PAGE_SHIFT, true);
1346 }
1347
1348
1349 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1350 &cached_state);
1351
1352 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1353 page_start, page_end - 1, &cached_state);
1354
1355 for (i = 0; i < i_done; i++) {
1356 clear_page_dirty_for_io(pages[i]);
1357 ClearPageChecked(pages[i]);
1358 set_page_extent_mapped(pages[i]);
1359 set_page_dirty(pages[i]);
1360 unlock_page(pages[i]);
1361 put_page(pages[i]);
1362 }
1363 btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT);
1364 extent_changeset_free(data_reserved);
1365 return i_done;
1366out:
1367 for (i = 0; i < i_done; i++) {
1368 unlock_page(pages[i]);
1369 put_page(pages[i]);
1370 }
1371 btrfs_delalloc_release_space(inode, data_reserved,
1372 start_index << PAGE_SHIFT,
1373 page_cnt << PAGE_SHIFT, true);
1374 btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT);
1375 extent_changeset_free(data_reserved);
1376 return ret;
1377
1378}
1379
1380int btrfs_defrag_file(struct inode *inode, struct file *file,
1381 struct btrfs_ioctl_defrag_range_args *range,
1382 u64 newer_than, unsigned long max_to_defrag)
1383{
1384 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1385 struct btrfs_root *root = BTRFS_I(inode)->root;
1386 struct file_ra_state *ra = NULL;
1387 unsigned long last_index;
1388 u64 isize = i_size_read(inode);
1389 u64 last_len = 0;
1390 u64 skip = 0;
1391 u64 defrag_end = 0;
1392 u64 newer_off = range->start;
1393 unsigned long i;
1394 unsigned long ra_index = 0;
1395 int ret;
1396 int defrag_count = 0;
1397 int compress_type = BTRFS_COMPRESS_ZLIB;
1398 u32 extent_thresh = range->extent_thresh;
1399 unsigned long max_cluster = SZ_256K >> PAGE_SHIFT;
1400 unsigned long cluster = max_cluster;
1401 u64 new_align = ~((u64)SZ_128K - 1);
1402 struct page **pages = NULL;
1403 bool do_compress = range->flags & BTRFS_DEFRAG_RANGE_COMPRESS;
1404
1405 if (isize == 0)
1406 return 0;
1407
1408 if (range->start >= isize)
1409 return -EINVAL;
1410
1411 if (do_compress) {
1412 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1413 return -EINVAL;
1414 if (range->compress_type)
1415 compress_type = range->compress_type;
1416 }
1417
1418 if (extent_thresh == 0)
1419 extent_thresh = SZ_256K;
1420
1421 /*
1422 * If we were not given a file, allocate a readahead context. As
1423 * readahead is just an optimization, defrag will work without it so
1424 * we don't error out.
1425 */
1426 if (!file) {
1427 ra = kzalloc(sizeof(*ra), GFP_KERNEL);
1428 if (ra)
1429 file_ra_state_init(ra, inode->i_mapping);
1430 } else {
1431 ra = &file->f_ra;
1432 }
1433
1434 pages = kmalloc_array(max_cluster, sizeof(struct page *), GFP_KERNEL);
1435 if (!pages) {
1436 ret = -ENOMEM;
1437 goto out_ra;
1438 }
1439
1440 /* find the last page to defrag */
1441 if (range->start + range->len > range->start) {
1442 last_index = min_t(u64, isize - 1,
1443 range->start + range->len - 1) >> PAGE_SHIFT;
1444 } else {
1445 last_index = (isize - 1) >> PAGE_SHIFT;
1446 }
1447
1448 if (newer_than) {
1449 ret = find_new_extents(root, inode, newer_than,
1450 &newer_off, SZ_64K);
1451 if (!ret) {
1452 range->start = newer_off;
1453 /*
1454 * we always align our defrag to help keep
1455 * the extents in the file evenly spaced
1456 */
1457 i = (newer_off & new_align) >> PAGE_SHIFT;
1458 } else
1459 goto out_ra;
1460 } else {
1461 i = range->start >> PAGE_SHIFT;
1462 }
1463 if (!max_to_defrag)
1464 max_to_defrag = last_index - i + 1;
1465
1466 /*
1467 * make writeback starts from i, so the defrag range can be
1468 * written sequentially.
1469 */
1470 if (i < inode->i_mapping->writeback_index)
1471 inode->i_mapping->writeback_index = i;
1472
1473 while (i <= last_index && defrag_count < max_to_defrag &&
1474 (i < DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE))) {
1475 /*
1476 * make sure we stop running if someone unmounts
1477 * the FS
1478 */
1479 if (!(inode->i_sb->s_flags & SB_ACTIVE))
1480 break;
1481
1482 if (btrfs_defrag_cancelled(fs_info)) {
1483 btrfs_debug(fs_info, "defrag_file cancelled");
1484 ret = -EAGAIN;
1485 break;
1486 }
1487
1488 if (!should_defrag_range(inode, (u64)i << PAGE_SHIFT,
1489 extent_thresh, &last_len, &skip,
1490 &defrag_end, do_compress)){
1491 unsigned long next;
1492 /*
1493 * the should_defrag function tells us how much to skip
1494 * bump our counter by the suggested amount
1495 */
1496 next = DIV_ROUND_UP(skip, PAGE_SIZE);
1497 i = max(i + 1, next);
1498 continue;
1499 }
1500
1501 if (!newer_than) {
1502 cluster = (PAGE_ALIGN(defrag_end) >>
1503 PAGE_SHIFT) - i;
1504 cluster = min(cluster, max_cluster);
1505 } else {
1506 cluster = max_cluster;
1507 }
1508
1509 if (i + cluster > ra_index) {
1510 ra_index = max(i, ra_index);
1511 if (ra)
1512 page_cache_sync_readahead(inode->i_mapping, ra,
1513 file, ra_index, cluster);
1514 ra_index += cluster;
1515 }
1516
1517 inode_lock(inode);
1518 if (IS_SWAPFILE(inode)) {
1519 ret = -ETXTBSY;
1520 } else {
1521 if (do_compress)
1522 BTRFS_I(inode)->defrag_compress = compress_type;
1523 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1524 }
1525 if (ret < 0) {
1526 inode_unlock(inode);
1527 goto out_ra;
1528 }
1529
1530 defrag_count += ret;
1531 balance_dirty_pages_ratelimited(inode->i_mapping);
1532 inode_unlock(inode);
1533
1534 if (newer_than) {
1535 if (newer_off == (u64)-1)
1536 break;
1537
1538 if (ret > 0)
1539 i += ret;
1540
1541 newer_off = max(newer_off + 1,
1542 (u64)i << PAGE_SHIFT);
1543
1544 ret = find_new_extents(root, inode, newer_than,
1545 &newer_off, SZ_64K);
1546 if (!ret) {
1547 range->start = newer_off;
1548 i = (newer_off & new_align) >> PAGE_SHIFT;
1549 } else {
1550 break;
1551 }
1552 } else {
1553 if (ret > 0) {
1554 i += ret;
1555 last_len += ret << PAGE_SHIFT;
1556 } else {
1557 i++;
1558 last_len = 0;
1559 }
1560 }
1561 }
1562
1563 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1564 filemap_flush(inode->i_mapping);
1565 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1566 &BTRFS_I(inode)->runtime_flags))
1567 filemap_flush(inode->i_mapping);
1568 }
1569
1570 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1571 btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
1572 } else if (range->compress_type == BTRFS_COMPRESS_ZSTD) {
1573 btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
1574 }
1575
1576 ret = defrag_count;
1577
1578out_ra:
1579 if (do_compress) {
1580 inode_lock(inode);
1581 BTRFS_I(inode)->defrag_compress = BTRFS_COMPRESS_NONE;
1582 inode_unlock(inode);
1583 }
1584 if (!file)
1585 kfree(ra);
1586 kfree(pages);
1587 return ret;
1588}
1589
1590static noinline int btrfs_ioctl_resize(struct file *file,
1591 void __user *arg)
1592{
1593 struct inode *inode = file_inode(file);
1594 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1595 u64 new_size;
1596 u64 old_size;
1597 u64 devid = 1;
1598 struct btrfs_root *root = BTRFS_I(inode)->root;
1599 struct btrfs_ioctl_vol_args *vol_args;
1600 struct btrfs_trans_handle *trans;
1601 struct btrfs_device *device = NULL;
1602 char *sizestr;
1603 char *retptr;
1604 char *devstr = NULL;
1605 int ret = 0;
1606 int mod = 0;
1607
1608 if (!capable(CAP_SYS_ADMIN))
1609 return -EPERM;
1610
1611 ret = mnt_want_write_file(file);
1612 if (ret)
1613 return ret;
1614
1615 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
1616 mnt_drop_write_file(file);
1617 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1618 }
1619
1620 vol_args = memdup_user(arg, sizeof(*vol_args));
1621 if (IS_ERR(vol_args)) {
1622 ret = PTR_ERR(vol_args);
1623 goto out;
1624 }
1625
1626 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1627
1628 sizestr = vol_args->name;
1629 devstr = strchr(sizestr, ':');
1630 if (devstr) {
1631 sizestr = devstr + 1;
1632 *devstr = '\0';
1633 devstr = vol_args->name;
1634 ret = kstrtoull(devstr, 10, &devid);
1635 if (ret)
1636 goto out_free;
1637 if (!devid) {
1638 ret = -EINVAL;
1639 goto out_free;
1640 }
1641 btrfs_info(fs_info, "resizing devid %llu", devid);
1642 }
1643
1644 device = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
1645 if (!device) {
1646 btrfs_info(fs_info, "resizer unable to find device %llu",
1647 devid);
1648 ret = -ENODEV;
1649 goto out_free;
1650 }
1651
1652 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
1653 btrfs_info(fs_info,
1654 "resizer unable to apply on readonly device %llu",
1655 devid);
1656 ret = -EPERM;
1657 goto out_free;
1658 }
1659
1660 if (!strcmp(sizestr, "max"))
1661 new_size = device->bdev->bd_inode->i_size;
1662 else {
1663 if (sizestr[0] == '-') {
1664 mod = -1;
1665 sizestr++;
1666 } else if (sizestr[0] == '+') {
1667 mod = 1;
1668 sizestr++;
1669 }
1670 new_size = memparse(sizestr, &retptr);
1671 if (*retptr != '\0' || new_size == 0) {
1672 ret = -EINVAL;
1673 goto out_free;
1674 }
1675 }
1676
1677 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
1678 ret = -EPERM;
1679 goto out_free;
1680 }
1681
1682 old_size = btrfs_device_get_total_bytes(device);
1683
1684 if (mod < 0) {
1685 if (new_size > old_size) {
1686 ret = -EINVAL;
1687 goto out_free;
1688 }
1689 new_size = old_size - new_size;
1690 } else if (mod > 0) {
1691 if (new_size > ULLONG_MAX - old_size) {
1692 ret = -ERANGE;
1693 goto out_free;
1694 }
1695 new_size = old_size + new_size;
1696 }
1697
1698 if (new_size < SZ_256M) {
1699 ret = -EINVAL;
1700 goto out_free;
1701 }
1702 if (new_size > device->bdev->bd_inode->i_size) {
1703 ret = -EFBIG;
1704 goto out_free;
1705 }
1706
1707 new_size = round_down(new_size, fs_info->sectorsize);
1708
1709 btrfs_info_in_rcu(fs_info, "new size for %s is %llu",
1710 rcu_str_deref(device->name), new_size);
1711
1712 if (new_size > old_size) {
1713 trans = btrfs_start_transaction(root, 0);
1714 if (IS_ERR(trans)) {
1715 ret = PTR_ERR(trans);
1716 goto out_free;
1717 }
1718 ret = btrfs_grow_device(trans, device, new_size);
1719 btrfs_commit_transaction(trans);
1720 } else if (new_size < old_size) {
1721 ret = btrfs_shrink_device(device, new_size);
1722 } /* equal, nothing need to do */
1723
1724out_free:
1725 kfree(vol_args);
1726out:
1727 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
1728 mnt_drop_write_file(file);
1729 return ret;
1730}
1731
1732static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1733 const char *name, unsigned long fd, int subvol,
1734 u64 *transid, bool readonly,
1735 struct btrfs_qgroup_inherit *inherit)
1736{
1737 int namelen;
1738 int ret = 0;
1739
1740 if (!S_ISDIR(file_inode(file)->i_mode))
1741 return -ENOTDIR;
1742
1743 ret = mnt_want_write_file(file);
1744 if (ret)
1745 goto out;
1746
1747 namelen = strlen(name);
1748 if (strchr(name, '/')) {
1749 ret = -EINVAL;
1750 goto out_drop_write;
1751 }
1752
1753 if (name[0] == '.' &&
1754 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1755 ret = -EEXIST;
1756 goto out_drop_write;
1757 }
1758
1759 if (subvol) {
1760 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1761 NULL, transid, readonly, inherit);
1762 } else {
1763 struct fd src = fdget(fd);
1764 struct inode *src_inode;
1765 if (!src.file) {
1766 ret = -EINVAL;
1767 goto out_drop_write;
1768 }
1769
1770 src_inode = file_inode(src.file);
1771 if (src_inode->i_sb != file_inode(file)->i_sb) {
1772 btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
1773 "Snapshot src from another FS");
1774 ret = -EXDEV;
1775 } else if (!inode_owner_or_capable(src_inode)) {
1776 /*
1777 * Subvolume creation is not restricted, but snapshots
1778 * are limited to own subvolumes only
1779 */
1780 ret = -EPERM;
1781 } else {
1782 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1783 BTRFS_I(src_inode)->root,
1784 transid, readonly, inherit);
1785 }
1786 fdput(src);
1787 }
1788out_drop_write:
1789 mnt_drop_write_file(file);
1790out:
1791 return ret;
1792}
1793
1794static noinline int btrfs_ioctl_snap_create(struct file *file,
1795 void __user *arg, int subvol)
1796{
1797 struct btrfs_ioctl_vol_args *vol_args;
1798 int ret;
1799
1800 if (!S_ISDIR(file_inode(file)->i_mode))
1801 return -ENOTDIR;
1802
1803 vol_args = memdup_user(arg, sizeof(*vol_args));
1804 if (IS_ERR(vol_args))
1805 return PTR_ERR(vol_args);
1806 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1807
1808 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1809 vol_args->fd, subvol,
1810 NULL, false, NULL);
1811
1812 kfree(vol_args);
1813 return ret;
1814}
1815
1816static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1817 void __user *arg, int subvol)
1818{
1819 struct btrfs_ioctl_vol_args_v2 *vol_args;
1820 int ret;
1821 u64 transid = 0;
1822 u64 *ptr = NULL;
1823 bool readonly = false;
1824 struct btrfs_qgroup_inherit *inherit = NULL;
1825
1826 if (!S_ISDIR(file_inode(file)->i_mode))
1827 return -ENOTDIR;
1828
1829 vol_args = memdup_user(arg, sizeof(*vol_args));
1830 if (IS_ERR(vol_args))
1831 return PTR_ERR(vol_args);
1832 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1833
1834 if (vol_args->flags &
1835 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1836 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1837 ret = -EOPNOTSUPP;
1838 goto free_args;
1839 }
1840
1841 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1842 struct inode *inode = file_inode(file);
1843 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1844
1845 btrfs_warn(fs_info,
1846"SNAP_CREATE_V2 ioctl with CREATE_ASYNC is deprecated and will be removed in kernel 5.7");
1847
1848 ptr = &transid;
1849 }
1850 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1851 readonly = true;
1852 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1853 if (vol_args->size > PAGE_SIZE) {
1854 ret = -EINVAL;
1855 goto free_args;
1856 }
1857 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1858 if (IS_ERR(inherit)) {
1859 ret = PTR_ERR(inherit);
1860 goto free_args;
1861 }
1862 }
1863
1864 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1865 vol_args->fd, subvol, ptr,
1866 readonly, inherit);
1867 if (ret)
1868 goto free_inherit;
1869
1870 if (ptr && copy_to_user(arg +
1871 offsetof(struct btrfs_ioctl_vol_args_v2,
1872 transid),
1873 ptr, sizeof(*ptr)))
1874 ret = -EFAULT;
1875
1876free_inherit:
1877 kfree(inherit);
1878free_args:
1879 kfree(vol_args);
1880 return ret;
1881}
1882
1883static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1884 void __user *arg)
1885{
1886 struct inode *inode = file_inode(file);
1887 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1888 struct btrfs_root *root = BTRFS_I(inode)->root;
1889 int ret = 0;
1890 u64 flags = 0;
1891
1892 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)
1893 return -EINVAL;
1894
1895 down_read(&fs_info->subvol_sem);
1896 if (btrfs_root_readonly(root))
1897 flags |= BTRFS_SUBVOL_RDONLY;
1898 up_read(&fs_info->subvol_sem);
1899
1900 if (copy_to_user(arg, &flags, sizeof(flags)))
1901 ret = -EFAULT;
1902
1903 return ret;
1904}
1905
1906static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1907 void __user *arg)
1908{
1909 struct inode *inode = file_inode(file);
1910 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1911 struct btrfs_root *root = BTRFS_I(inode)->root;
1912 struct btrfs_trans_handle *trans;
1913 u64 root_flags;
1914 u64 flags;
1915 int ret = 0;
1916
1917 if (!inode_owner_or_capable(inode))
1918 return -EPERM;
1919
1920 ret = mnt_want_write_file(file);
1921 if (ret)
1922 goto out;
1923
1924 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
1925 ret = -EINVAL;
1926 goto out_drop_write;
1927 }
1928
1929 if (copy_from_user(&flags, arg, sizeof(flags))) {
1930 ret = -EFAULT;
1931 goto out_drop_write;
1932 }
1933
1934 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1935 ret = -EINVAL;
1936 goto out_drop_write;
1937 }
1938
1939 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1940 ret = -EOPNOTSUPP;
1941 goto out_drop_write;
1942 }
1943
1944 down_write(&fs_info->subvol_sem);
1945
1946 /* nothing to do */
1947 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1948 goto out_drop_sem;
1949
1950 root_flags = btrfs_root_flags(&root->root_item);
1951 if (flags & BTRFS_SUBVOL_RDONLY) {
1952 btrfs_set_root_flags(&root->root_item,
1953 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1954 } else {
1955 /*
1956 * Block RO -> RW transition if this subvolume is involved in
1957 * send
1958 */
1959 spin_lock(&root->root_item_lock);
1960 if (root->send_in_progress == 0) {
1961 btrfs_set_root_flags(&root->root_item,
1962 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1963 spin_unlock(&root->root_item_lock);
1964 } else {
1965 spin_unlock(&root->root_item_lock);
1966 btrfs_warn(fs_info,
1967 "Attempt to set subvolume %llu read-write during send",
1968 root->root_key.objectid);
1969 ret = -EPERM;
1970 goto out_drop_sem;
1971 }
1972 }
1973
1974 trans = btrfs_start_transaction(root, 1);
1975 if (IS_ERR(trans)) {
1976 ret = PTR_ERR(trans);
1977 goto out_reset;
1978 }
1979
1980 ret = btrfs_update_root(trans, fs_info->tree_root,
1981 &root->root_key, &root->root_item);
1982 if (ret < 0) {
1983 btrfs_end_transaction(trans);
1984 goto out_reset;
1985 }
1986
1987 ret = btrfs_commit_transaction(trans);
1988
1989out_reset:
1990 if (ret)
1991 btrfs_set_root_flags(&root->root_item, root_flags);
1992out_drop_sem:
1993 up_write(&fs_info->subvol_sem);
1994out_drop_write:
1995 mnt_drop_write_file(file);
1996out:
1997 return ret;
1998}
1999
2000static noinline int key_in_sk(struct btrfs_key *key,
2001 struct btrfs_ioctl_search_key *sk)
2002{
2003 struct btrfs_key test;
2004 int ret;
2005
2006 test.objectid = sk->min_objectid;
2007 test.type = sk->min_type;
2008 test.offset = sk->min_offset;
2009
2010 ret = btrfs_comp_cpu_keys(key, &test);
2011 if (ret < 0)
2012 return 0;
2013
2014 test.objectid = sk->max_objectid;
2015 test.type = sk->max_type;
2016 test.offset = sk->max_offset;
2017
2018 ret = btrfs_comp_cpu_keys(key, &test);
2019 if (ret > 0)
2020 return 0;
2021 return 1;
2022}
2023
2024static noinline int copy_to_sk(struct btrfs_path *path,
2025 struct btrfs_key *key,
2026 struct btrfs_ioctl_search_key *sk,
2027 size_t *buf_size,
2028 char __user *ubuf,
2029 unsigned long *sk_offset,
2030 int *num_found)
2031{
2032 u64 found_transid;
2033 struct extent_buffer *leaf;
2034 struct btrfs_ioctl_search_header sh;
2035 struct btrfs_key test;
2036 unsigned long item_off;
2037 unsigned long item_len;
2038 int nritems;
2039 int i;
2040 int slot;
2041 int ret = 0;
2042
2043 leaf = path->nodes[0];
2044 slot = path->slots[0];
2045 nritems = btrfs_header_nritems(leaf);
2046
2047 if (btrfs_header_generation(leaf) > sk->max_transid) {
2048 i = nritems;
2049 goto advance_key;
2050 }
2051 found_transid = btrfs_header_generation(leaf);
2052
2053 for (i = slot; i < nritems; i++) {
2054 item_off = btrfs_item_ptr_offset(leaf, i);
2055 item_len = btrfs_item_size_nr(leaf, i);
2056
2057 btrfs_item_key_to_cpu(leaf, key, i);
2058 if (!key_in_sk(key, sk))
2059 continue;
2060
2061 if (sizeof(sh) + item_len > *buf_size) {
2062 if (*num_found) {
2063 ret = 1;
2064 goto out;
2065 }
2066
2067 /*
2068 * return one empty item back for v1, which does not
2069 * handle -EOVERFLOW
2070 */
2071
2072 *buf_size = sizeof(sh) + item_len;
2073 item_len = 0;
2074 ret = -EOVERFLOW;
2075 }
2076
2077 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2078 ret = 1;
2079 goto out;
2080 }
2081
2082 sh.objectid = key->objectid;
2083 sh.offset = key->offset;
2084 sh.type = key->type;
2085 sh.len = item_len;
2086 sh.transid = found_transid;
2087
2088 /* copy search result header */
2089 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
2090 ret = -EFAULT;
2091 goto out;
2092 }
2093
2094 *sk_offset += sizeof(sh);
2095
2096 if (item_len) {
2097 char __user *up = ubuf + *sk_offset;
2098 /* copy the item */
2099 if (read_extent_buffer_to_user(leaf, up,
2100 item_off, item_len)) {
2101 ret = -EFAULT;
2102 goto out;
2103 }
2104
2105 *sk_offset += item_len;
2106 }
2107 (*num_found)++;
2108
2109 if (ret) /* -EOVERFLOW from above */
2110 goto out;
2111
2112 if (*num_found >= sk->nr_items) {
2113 ret = 1;
2114 goto out;
2115 }
2116 }
2117advance_key:
2118 ret = 0;
2119 test.objectid = sk->max_objectid;
2120 test.type = sk->max_type;
2121 test.offset = sk->max_offset;
2122 if (btrfs_comp_cpu_keys(key, &test) >= 0)
2123 ret = 1;
2124 else if (key->offset < (u64)-1)
2125 key->offset++;
2126 else if (key->type < (u8)-1) {
2127 key->offset = 0;
2128 key->type++;
2129 } else if (key->objectid < (u64)-1) {
2130 key->offset = 0;
2131 key->type = 0;
2132 key->objectid++;
2133 } else
2134 ret = 1;
2135out:
2136 /*
2137 * 0: all items from this leaf copied, continue with next
2138 * 1: * more items can be copied, but unused buffer is too small
2139 * * all items were found
2140 * Either way, it will stops the loop which iterates to the next
2141 * leaf
2142 * -EOVERFLOW: item was to large for buffer
2143 * -EFAULT: could not copy extent buffer back to userspace
2144 */
2145 return ret;
2146}
2147
2148static noinline int search_ioctl(struct inode *inode,
2149 struct btrfs_ioctl_search_key *sk,
2150 size_t *buf_size,
2151 char __user *ubuf)
2152{
2153 struct btrfs_fs_info *info = btrfs_sb(inode->i_sb);
2154 struct btrfs_root *root;
2155 struct btrfs_key key;
2156 struct btrfs_path *path;
2157 int ret;
2158 int num_found = 0;
2159 unsigned long sk_offset = 0;
2160
2161 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2162 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2163 return -EOVERFLOW;
2164 }
2165
2166 path = btrfs_alloc_path();
2167 if (!path)
2168 return -ENOMEM;
2169
2170 if (sk->tree_id == 0) {
2171 /* search the root of the inode that was passed */
2172 root = BTRFS_I(inode)->root;
2173 } else {
2174 key.objectid = sk->tree_id;
2175 key.type = BTRFS_ROOT_ITEM_KEY;
2176 key.offset = (u64)-1;
2177 root = btrfs_read_fs_root_no_name(info, &key);
2178 if (IS_ERR(root)) {
2179 btrfs_free_path(path);
2180 return PTR_ERR(root);
2181 }
2182 }
2183
2184 key.objectid = sk->min_objectid;
2185 key.type = sk->min_type;
2186 key.offset = sk->min_offset;
2187
2188 while (1) {
2189 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2190 if (ret != 0) {
2191 if (ret > 0)
2192 ret = 0;
2193 goto err;
2194 }
2195 ret = copy_to_sk(path, &key, sk, buf_size, ubuf,
2196 &sk_offset, &num_found);
2197 btrfs_release_path(path);
2198 if (ret)
2199 break;
2200
2201 }
2202 if (ret > 0)
2203 ret = 0;
2204err:
2205 sk->nr_items = num_found;
2206 btrfs_free_path(path);
2207 return ret;
2208}
2209
2210static noinline int btrfs_ioctl_tree_search(struct file *file,
2211 void __user *argp)
2212{
2213 struct btrfs_ioctl_search_args __user *uargs;
2214 struct btrfs_ioctl_search_key sk;
2215 struct inode *inode;
2216 int ret;
2217 size_t buf_size;
2218
2219 if (!capable(CAP_SYS_ADMIN))
2220 return -EPERM;
2221
2222 uargs = (struct btrfs_ioctl_search_args __user *)argp;
2223
2224 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2225 return -EFAULT;
2226
2227 buf_size = sizeof(uargs->buf);
2228
2229 inode = file_inode(file);
2230 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2231
2232 /*
2233 * In the origin implementation an overflow is handled by returning a
2234 * search header with a len of zero, so reset ret.
2235 */
2236 if (ret == -EOVERFLOW)
2237 ret = 0;
2238
2239 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2240 ret = -EFAULT;
2241 return ret;
2242}
2243
2244static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2245 void __user *argp)
2246{
2247 struct btrfs_ioctl_search_args_v2 __user *uarg;
2248 struct btrfs_ioctl_search_args_v2 args;
2249 struct inode *inode;
2250 int ret;
2251 size_t buf_size;
2252 const size_t buf_limit = SZ_16M;
2253
2254 if (!capable(CAP_SYS_ADMIN))
2255 return -EPERM;
2256
2257 /* copy search header and buffer size */
2258 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2259 if (copy_from_user(&args, uarg, sizeof(args)))
2260 return -EFAULT;
2261
2262 buf_size = args.buf_size;
2263
2264 /* limit result size to 16MB */
2265 if (buf_size > buf_limit)
2266 buf_size = buf_limit;
2267
2268 inode = file_inode(file);
2269 ret = search_ioctl(inode, &args.key, &buf_size,
2270 (char __user *)(&uarg->buf[0]));
2271 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2272 ret = -EFAULT;
2273 else if (ret == -EOVERFLOW &&
2274 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2275 ret = -EFAULT;
2276
2277 return ret;
2278}
2279
2280/*
2281 * Search INODE_REFs to identify path name of 'dirid' directory
2282 * in a 'tree_id' tree. and sets path name to 'name'.
2283 */
2284static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2285 u64 tree_id, u64 dirid, char *name)
2286{
2287 struct btrfs_root *root;
2288 struct btrfs_key key;
2289 char *ptr;
2290 int ret = -1;
2291 int slot;
2292 int len;
2293 int total_len = 0;
2294 struct btrfs_inode_ref *iref;
2295 struct extent_buffer *l;
2296 struct btrfs_path *path;
2297
2298 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2299 name[0]='\0';
2300 return 0;
2301 }
2302
2303 path = btrfs_alloc_path();
2304 if (!path)
2305 return -ENOMEM;
2306
2307 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1];
2308
2309 key.objectid = tree_id;
2310 key.type = BTRFS_ROOT_ITEM_KEY;
2311 key.offset = (u64)-1;
2312 root = btrfs_read_fs_root_no_name(info, &key);
2313 if (IS_ERR(root)) {
2314 ret = PTR_ERR(root);
2315 goto out;
2316 }
2317
2318 key.objectid = dirid;
2319 key.type = BTRFS_INODE_REF_KEY;
2320 key.offset = (u64)-1;
2321
2322 while (1) {
2323 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2324 if (ret < 0)
2325 goto out;
2326 else if (ret > 0) {
2327 ret = btrfs_previous_item(root, path, dirid,
2328 BTRFS_INODE_REF_KEY);
2329 if (ret < 0)
2330 goto out;
2331 else if (ret > 0) {
2332 ret = -ENOENT;
2333 goto out;
2334 }
2335 }
2336
2337 l = path->nodes[0];
2338 slot = path->slots[0];
2339 btrfs_item_key_to_cpu(l, &key, slot);
2340
2341 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2342 len = btrfs_inode_ref_name_len(l, iref);
2343 ptr -= len + 1;
2344 total_len += len + 1;
2345 if (ptr < name) {
2346 ret = -ENAMETOOLONG;
2347 goto out;
2348 }
2349
2350 *(ptr + len) = '/';
2351 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2352
2353 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2354 break;
2355
2356 btrfs_release_path(path);
2357 key.objectid = key.offset;
2358 key.offset = (u64)-1;
2359 dirid = key.objectid;
2360 }
2361 memmove(name, ptr, total_len);
2362 name[total_len] = '\0';
2363 ret = 0;
2364out:
2365 btrfs_free_path(path);
2366 return ret;
2367}
2368
2369static int btrfs_search_path_in_tree_user(struct inode *inode,
2370 struct btrfs_ioctl_ino_lookup_user_args *args)
2371{
2372 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2373 struct super_block *sb = inode->i_sb;
2374 struct btrfs_key upper_limit = BTRFS_I(inode)->location;
2375 u64 treeid = BTRFS_I(inode)->root->root_key.objectid;
2376 u64 dirid = args->dirid;
2377 unsigned long item_off;
2378 unsigned long item_len;
2379 struct btrfs_inode_ref *iref;
2380 struct btrfs_root_ref *rref;
2381 struct btrfs_root *root;
2382 struct btrfs_path *path;
2383 struct btrfs_key key, key2;
2384 struct extent_buffer *leaf;
2385 struct inode *temp_inode;
2386 char *ptr;
2387 int slot;
2388 int len;
2389 int total_len = 0;
2390 int ret;
2391
2392 path = btrfs_alloc_path();
2393 if (!path)
2394 return -ENOMEM;
2395
2396 /*
2397 * If the bottom subvolume does not exist directly under upper_limit,
2398 * construct the path in from the bottom up.
2399 */
2400 if (dirid != upper_limit.objectid) {
2401 ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1];
2402
2403 key.objectid = treeid;
2404 key.type = BTRFS_ROOT_ITEM_KEY;
2405 key.offset = (u64)-1;
2406 root = btrfs_read_fs_root_no_name(fs_info, &key);
2407 if (IS_ERR(root)) {
2408 ret = PTR_ERR(root);
2409 goto out;
2410 }
2411
2412 key.objectid = dirid;
2413 key.type = BTRFS_INODE_REF_KEY;
2414 key.offset = (u64)-1;
2415 while (1) {
2416 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2417 if (ret < 0) {
2418 goto out;
2419 } else if (ret > 0) {
2420 ret = btrfs_previous_item(root, path, dirid,
2421 BTRFS_INODE_REF_KEY);
2422 if (ret < 0) {
2423 goto out;
2424 } else if (ret > 0) {
2425 ret = -ENOENT;
2426 goto out;
2427 }
2428 }
2429
2430 leaf = path->nodes[0];
2431 slot = path->slots[0];
2432 btrfs_item_key_to_cpu(leaf, &key, slot);
2433
2434 iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref);
2435 len = btrfs_inode_ref_name_len(leaf, iref);
2436 ptr -= len + 1;
2437 total_len += len + 1;
2438 if (ptr < args->path) {
2439 ret = -ENAMETOOLONG;
2440 goto out;
2441 }
2442
2443 *(ptr + len) = '/';
2444 read_extent_buffer(leaf, ptr,
2445 (unsigned long)(iref + 1), len);
2446
2447 /* Check the read+exec permission of this directory */
2448 ret = btrfs_previous_item(root, path, dirid,
2449 BTRFS_INODE_ITEM_KEY);
2450 if (ret < 0) {
2451 goto out;
2452 } else if (ret > 0) {
2453 ret = -ENOENT;
2454 goto out;
2455 }
2456
2457 leaf = path->nodes[0];
2458 slot = path->slots[0];
2459 btrfs_item_key_to_cpu(leaf, &key2, slot);
2460 if (key2.objectid != dirid) {
2461 ret = -ENOENT;
2462 goto out;
2463 }
2464
2465 temp_inode = btrfs_iget(sb, &key2, root, NULL);
2466 if (IS_ERR(temp_inode)) {
2467 ret = PTR_ERR(temp_inode);
2468 goto out;
2469 }
2470 ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC);
2471 iput(temp_inode);
2472 if (ret) {
2473 ret = -EACCES;
2474 goto out;
2475 }
2476
2477 if (key.offset == upper_limit.objectid)
2478 break;
2479 if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {
2480 ret = -EACCES;
2481 goto out;
2482 }
2483
2484 btrfs_release_path(path);
2485 key.objectid = key.offset;
2486 key.offset = (u64)-1;
2487 dirid = key.objectid;
2488 }
2489
2490 memmove(args->path, ptr, total_len);
2491 args->path[total_len] = '\0';
2492 btrfs_release_path(path);
2493 }
2494
2495 /* Get the bottom subvolume's name from ROOT_REF */
2496 root = fs_info->tree_root;
2497 key.objectid = treeid;
2498 key.type = BTRFS_ROOT_REF_KEY;
2499 key.offset = args->treeid;
2500 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2501 if (ret < 0) {
2502 goto out;
2503 } else if (ret > 0) {
2504 ret = -ENOENT;
2505 goto out;
2506 }
2507
2508 leaf = path->nodes[0];
2509 slot = path->slots[0];
2510 btrfs_item_key_to_cpu(leaf, &key, slot);
2511
2512 item_off = btrfs_item_ptr_offset(leaf, slot);
2513 item_len = btrfs_item_size_nr(leaf, slot);
2514 /* Check if dirid in ROOT_REF corresponds to passed dirid */
2515 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2516 if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) {
2517 ret = -EINVAL;
2518 goto out;
2519 }
2520
2521 /* Copy subvolume's name */
2522 item_off += sizeof(struct btrfs_root_ref);
2523 item_len -= sizeof(struct btrfs_root_ref);
2524 read_extent_buffer(leaf, args->name, item_off, item_len);
2525 args->name[item_len] = 0;
2526
2527out:
2528 btrfs_free_path(path);
2529 return ret;
2530}
2531
2532static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2533 void __user *argp)
2534{
2535 struct btrfs_ioctl_ino_lookup_args *args;
2536 struct inode *inode;
2537 int ret = 0;
2538
2539 args = memdup_user(argp, sizeof(*args));
2540 if (IS_ERR(args))
2541 return PTR_ERR(args);
2542
2543 inode = file_inode(file);
2544
2545 /*
2546 * Unprivileged query to obtain the containing subvolume root id. The
2547 * path is reset so it's consistent with btrfs_search_path_in_tree.
2548 */
2549 if (args->treeid == 0)
2550 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2551
2552 if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2553 args->name[0] = 0;
2554 goto out;
2555 }
2556
2557 if (!capable(CAP_SYS_ADMIN)) {
2558 ret = -EPERM;
2559 goto out;
2560 }
2561
2562 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2563 args->treeid, args->objectid,
2564 args->name);
2565
2566out:
2567 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2568 ret = -EFAULT;
2569
2570 kfree(args);
2571 return ret;
2572}
2573
2574/*
2575 * Version of ino_lookup ioctl (unprivileged)
2576 *
2577 * The main differences from ino_lookup ioctl are:
2578 *
2579 * 1. Read + Exec permission will be checked using inode_permission() during
2580 * path construction. -EACCES will be returned in case of failure.
2581 * 2. Path construction will be stopped at the inode number which corresponds
2582 * to the fd with which this ioctl is called. If constructed path does not
2583 * exist under fd's inode, -EACCES will be returned.
2584 * 3. The name of bottom subvolume is also searched and filled.
2585 */
2586static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp)
2587{
2588 struct btrfs_ioctl_ino_lookup_user_args *args;
2589 struct inode *inode;
2590 int ret;
2591
2592 args = memdup_user(argp, sizeof(*args));
2593 if (IS_ERR(args))
2594 return PTR_ERR(args);
2595
2596 inode = file_inode(file);
2597
2598 if (args->dirid == BTRFS_FIRST_FREE_OBJECTID &&
2599 BTRFS_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) {
2600 /*
2601 * The subvolume does not exist under fd with which this is
2602 * called
2603 */
2604 kfree(args);
2605 return -EACCES;
2606 }
2607
2608 ret = btrfs_search_path_in_tree_user(inode, args);
2609
2610 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2611 ret = -EFAULT;
2612
2613 kfree(args);
2614 return ret;
2615}
2616
2617/* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */
2618static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp)
2619{
2620 struct btrfs_ioctl_get_subvol_info_args *subvol_info;
2621 struct btrfs_fs_info *fs_info;
2622 struct btrfs_root *root;
2623 struct btrfs_path *path;
2624 struct btrfs_key key;
2625 struct btrfs_root_item *root_item;
2626 struct btrfs_root_ref *rref;
2627 struct extent_buffer *leaf;
2628 unsigned long item_off;
2629 unsigned long item_len;
2630 struct inode *inode;
2631 int slot;
2632 int ret = 0;
2633
2634 path = btrfs_alloc_path();
2635 if (!path)
2636 return -ENOMEM;
2637
2638 subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL);
2639 if (!subvol_info) {
2640 btrfs_free_path(path);
2641 return -ENOMEM;
2642 }
2643
2644 inode = file_inode(file);
2645 fs_info = BTRFS_I(inode)->root->fs_info;
2646
2647 /* Get root_item of inode's subvolume */
2648 key.objectid = BTRFS_I(inode)->root->root_key.objectid;
2649 key.type = BTRFS_ROOT_ITEM_KEY;
2650 key.offset = (u64)-1;
2651 root = btrfs_read_fs_root_no_name(fs_info, &key);
2652 if (IS_ERR(root)) {
2653 ret = PTR_ERR(root);
2654 goto out;
2655 }
2656 root_item = &root->root_item;
2657
2658 subvol_info->treeid = key.objectid;
2659
2660 subvol_info->generation = btrfs_root_generation(root_item);
2661 subvol_info->flags = btrfs_root_flags(root_item);
2662
2663 memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE);
2664 memcpy(subvol_info->parent_uuid, root_item->parent_uuid,
2665 BTRFS_UUID_SIZE);
2666 memcpy(subvol_info->received_uuid, root_item->received_uuid,
2667 BTRFS_UUID_SIZE);
2668
2669 subvol_info->ctransid = btrfs_root_ctransid(root_item);
2670 subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime);
2671 subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime);
2672
2673 subvol_info->otransid = btrfs_root_otransid(root_item);
2674 subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime);
2675 subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime);
2676
2677 subvol_info->stransid = btrfs_root_stransid(root_item);
2678 subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime);
2679 subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime);
2680
2681 subvol_info->rtransid = btrfs_root_rtransid(root_item);
2682 subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime);
2683 subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime);
2684
2685 if (key.objectid != BTRFS_FS_TREE_OBJECTID) {
2686 /* Search root tree for ROOT_BACKREF of this subvolume */
2687 root = fs_info->tree_root;
2688
2689 key.type = BTRFS_ROOT_BACKREF_KEY;
2690 key.offset = 0;
2691 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2692 if (ret < 0) {
2693 goto out;
2694 } else if (path->slots[0] >=
2695 btrfs_header_nritems(path->nodes[0])) {
2696 ret = btrfs_next_leaf(root, path);
2697 if (ret < 0) {
2698 goto out;
2699 } else if (ret > 0) {
2700 ret = -EUCLEAN;
2701 goto out;
2702 }
2703 }
2704
2705 leaf = path->nodes[0];
2706 slot = path->slots[0];
2707 btrfs_item_key_to_cpu(leaf, &key, slot);
2708 if (key.objectid == subvol_info->treeid &&
2709 key.type == BTRFS_ROOT_BACKREF_KEY) {
2710 subvol_info->parent_id = key.offset;
2711
2712 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2713 subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref);
2714
2715 item_off = btrfs_item_ptr_offset(leaf, slot)
2716 + sizeof(struct btrfs_root_ref);
2717 item_len = btrfs_item_size_nr(leaf, slot)
2718 - sizeof(struct btrfs_root_ref);
2719 read_extent_buffer(leaf, subvol_info->name,
2720 item_off, item_len);
2721 } else {
2722 ret = -ENOENT;
2723 goto out;
2724 }
2725 }
2726
2727 if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))
2728 ret = -EFAULT;
2729
2730out:
2731 btrfs_free_path(path);
2732 kzfree(subvol_info);
2733 return ret;
2734}
2735
2736/*
2737 * Return ROOT_REF information of the subvolume containing this inode
2738 * except the subvolume name.
2739 */
2740static int btrfs_ioctl_get_subvol_rootref(struct file *file, void __user *argp)
2741{
2742 struct btrfs_ioctl_get_subvol_rootref_args *rootrefs;
2743 struct btrfs_root_ref *rref;
2744 struct btrfs_root *root;
2745 struct btrfs_path *path;
2746 struct btrfs_key key;
2747 struct extent_buffer *leaf;
2748 struct inode *inode;
2749 u64 objectid;
2750 int slot;
2751 int ret;
2752 u8 found;
2753
2754 path = btrfs_alloc_path();
2755 if (!path)
2756 return -ENOMEM;
2757
2758 rootrefs = memdup_user(argp, sizeof(*rootrefs));
2759 if (IS_ERR(rootrefs)) {
2760 btrfs_free_path(path);
2761 return PTR_ERR(rootrefs);
2762 }
2763
2764 inode = file_inode(file);
2765 root = BTRFS_I(inode)->root->fs_info->tree_root;
2766 objectid = BTRFS_I(inode)->root->root_key.objectid;
2767
2768 key.objectid = objectid;
2769 key.type = BTRFS_ROOT_REF_KEY;
2770 key.offset = rootrefs->min_treeid;
2771 found = 0;
2772
2773 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2774 if (ret < 0) {
2775 goto out;
2776 } else if (path->slots[0] >=
2777 btrfs_header_nritems(path->nodes[0])) {
2778 ret = btrfs_next_leaf(root, path);
2779 if (ret < 0) {
2780 goto out;
2781 } else if (ret > 0) {
2782 ret = -EUCLEAN;
2783 goto out;
2784 }
2785 }
2786 while (1) {
2787 leaf = path->nodes[0];
2788 slot = path->slots[0];
2789
2790 btrfs_item_key_to_cpu(leaf, &key, slot);
2791 if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) {
2792 ret = 0;
2793 goto out;
2794 }
2795
2796 if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) {
2797 ret = -EOVERFLOW;
2798 goto out;
2799 }
2800
2801 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2802 rootrefs->rootref[found].treeid = key.offset;
2803 rootrefs->rootref[found].dirid =
2804 btrfs_root_ref_dirid(leaf, rref);
2805 found++;
2806
2807 ret = btrfs_next_item(root, path);
2808 if (ret < 0) {
2809 goto out;
2810 } else if (ret > 0) {
2811 ret = -EUCLEAN;
2812 goto out;
2813 }
2814 }
2815
2816out:
2817 if (!ret || ret == -EOVERFLOW) {
2818 rootrefs->num_items = found;
2819 /* update min_treeid for next search */
2820 if (found)
2821 rootrefs->min_treeid =
2822 rootrefs->rootref[found - 1].treeid + 1;
2823 if (copy_to_user(argp, rootrefs, sizeof(*rootrefs)))
2824 ret = -EFAULT;
2825 }
2826
2827 kfree(rootrefs);
2828 btrfs_free_path(path);
2829
2830 return ret;
2831}
2832
2833static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2834 void __user *arg)
2835{
2836 struct dentry *parent = file->f_path.dentry;
2837 struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb);
2838 struct dentry *dentry;
2839 struct inode *dir = d_inode(parent);
2840 struct inode *inode;
2841 struct btrfs_root *root = BTRFS_I(dir)->root;
2842 struct btrfs_root *dest = NULL;
2843 struct btrfs_ioctl_vol_args *vol_args;
2844 int namelen;
2845 int err = 0;
2846
2847 if (!S_ISDIR(dir->i_mode))
2848 return -ENOTDIR;
2849
2850 vol_args = memdup_user(arg, sizeof(*vol_args));
2851 if (IS_ERR(vol_args))
2852 return PTR_ERR(vol_args);
2853
2854 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2855 namelen = strlen(vol_args->name);
2856 if (strchr(vol_args->name, '/') ||
2857 strncmp(vol_args->name, "..", namelen) == 0) {
2858 err = -EINVAL;
2859 goto out;
2860 }
2861
2862 err = mnt_want_write_file(file);
2863 if (err)
2864 goto out;
2865
2866
2867 err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
2868 if (err == -EINTR)
2869 goto out_drop_write;
2870 dentry = lookup_one_len(vol_args->name, parent, namelen);
2871 if (IS_ERR(dentry)) {
2872 err = PTR_ERR(dentry);
2873 goto out_unlock_dir;
2874 }
2875
2876 if (d_really_is_negative(dentry)) {
2877 err = -ENOENT;
2878 goto out_dput;
2879 }
2880
2881 inode = d_inode(dentry);
2882 dest = BTRFS_I(inode)->root;
2883 if (!capable(CAP_SYS_ADMIN)) {
2884 /*
2885 * Regular user. Only allow this with a special mount
2886 * option, when the user has write+exec access to the
2887 * subvol root, and when rmdir(2) would have been
2888 * allowed.
2889 *
2890 * Note that this is _not_ check that the subvol is
2891 * empty or doesn't contain data that we wouldn't
2892 * otherwise be able to delete.
2893 *
2894 * Users who want to delete empty subvols should try
2895 * rmdir(2).
2896 */
2897 err = -EPERM;
2898 if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))
2899 goto out_dput;
2900
2901 /*
2902 * Do not allow deletion if the parent dir is the same
2903 * as the dir to be deleted. That means the ioctl
2904 * must be called on the dentry referencing the root
2905 * of the subvol, not a random directory contained
2906 * within it.
2907 */
2908 err = -EINVAL;
2909 if (root == dest)
2910 goto out_dput;
2911
2912 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2913 if (err)
2914 goto out_dput;
2915 }
2916
2917 /* check if subvolume may be deleted by a user */
2918 err = btrfs_may_delete(dir, dentry, 1);
2919 if (err)
2920 goto out_dput;
2921
2922 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
2923 err = -EINVAL;
2924 goto out_dput;
2925 }
2926
2927 inode_lock(inode);
2928 err = btrfs_delete_subvolume(dir, dentry);
2929 inode_unlock(inode);
2930 if (!err) {
2931 fsnotify_rmdir(dir, dentry);
2932 d_delete(dentry);
2933 }
2934
2935out_dput:
2936 dput(dentry);
2937out_unlock_dir:
2938 inode_unlock(dir);
2939out_drop_write:
2940 mnt_drop_write_file(file);
2941out:
2942 kfree(vol_args);
2943 return err;
2944}
2945
2946static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2947{
2948 struct inode *inode = file_inode(file);
2949 struct btrfs_root *root = BTRFS_I(inode)->root;
2950 struct btrfs_ioctl_defrag_range_args *range;
2951 int ret;
2952
2953 ret = mnt_want_write_file(file);
2954 if (ret)
2955 return ret;
2956
2957 if (btrfs_root_readonly(root)) {
2958 ret = -EROFS;
2959 goto out;
2960 }
2961
2962 switch (inode->i_mode & S_IFMT) {
2963 case S_IFDIR:
2964 if (!capable(CAP_SYS_ADMIN)) {
2965 ret = -EPERM;
2966 goto out;
2967 }
2968 ret = btrfs_defrag_root(root);
2969 break;
2970 case S_IFREG:
2971 /*
2972 * Note that this does not check the file descriptor for write
2973 * access. This prevents defragmenting executables that are
2974 * running and allows defrag on files open in read-only mode.
2975 */
2976 if (!capable(CAP_SYS_ADMIN) &&
2977 inode_permission(inode, MAY_WRITE)) {
2978 ret = -EPERM;
2979 goto out;
2980 }
2981
2982 range = kzalloc(sizeof(*range), GFP_KERNEL);
2983 if (!range) {
2984 ret = -ENOMEM;
2985 goto out;
2986 }
2987
2988 if (argp) {
2989 if (copy_from_user(range, argp,
2990 sizeof(*range))) {
2991 ret = -EFAULT;
2992 kfree(range);
2993 goto out;
2994 }
2995 /* compression requires us to start the IO */
2996 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2997 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2998 range->extent_thresh = (u32)-1;
2999 }
3000 } else {
3001 /* the rest are all set to zero by kzalloc */
3002 range->len = (u64)-1;
3003 }
3004 ret = btrfs_defrag_file(file_inode(file), file,
3005 range, BTRFS_OLDEST_GENERATION, 0);
3006 if (ret > 0)
3007 ret = 0;
3008 kfree(range);
3009 break;
3010 default:
3011 ret = -EINVAL;
3012 }
3013out:
3014 mnt_drop_write_file(file);
3015 return ret;
3016}
3017
3018static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg)
3019{
3020 struct btrfs_ioctl_vol_args *vol_args;
3021 int ret;
3022
3023 if (!capable(CAP_SYS_ADMIN))
3024 return -EPERM;
3025
3026 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags))
3027 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3028
3029 vol_args = memdup_user(arg, sizeof(*vol_args));
3030 if (IS_ERR(vol_args)) {
3031 ret = PTR_ERR(vol_args);
3032 goto out;
3033 }
3034
3035 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3036 ret = btrfs_init_new_device(fs_info, vol_args->name);
3037
3038 if (!ret)
3039 btrfs_info(fs_info, "disk added %s", vol_args->name);
3040
3041 kfree(vol_args);
3042out:
3043 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3044 return ret;
3045}
3046
3047static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
3048{
3049 struct inode *inode = file_inode(file);
3050 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3051 struct btrfs_ioctl_vol_args_v2 *vol_args;
3052 int ret;
3053
3054 if (!capable(CAP_SYS_ADMIN))
3055 return -EPERM;
3056
3057 ret = mnt_want_write_file(file);
3058 if (ret)
3059 return ret;
3060
3061 vol_args = memdup_user(arg, sizeof(*vol_args));
3062 if (IS_ERR(vol_args)) {
3063 ret = PTR_ERR(vol_args);
3064 goto err_drop;
3065 }
3066
3067 /* Check for compatibility reject unknown flags */
3068 if (vol_args->flags & ~BTRFS_VOL_ARG_V2_FLAGS_SUPPORTED) {
3069 ret = -EOPNOTSUPP;
3070 goto out;
3071 }
3072
3073 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
3074 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3075 goto out;
3076 }
3077
3078 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
3079 ret = btrfs_rm_device(fs_info, NULL, vol_args->devid);
3080 } else {
3081 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
3082 ret = btrfs_rm_device(fs_info, vol_args->name, 0);
3083 }
3084 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3085
3086 if (!ret) {
3087 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
3088 btrfs_info(fs_info, "device deleted: id %llu",
3089 vol_args->devid);
3090 else
3091 btrfs_info(fs_info, "device deleted: %s",
3092 vol_args->name);
3093 }
3094out:
3095 kfree(vol_args);
3096err_drop:
3097 mnt_drop_write_file(file);
3098 return ret;
3099}
3100
3101static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
3102{
3103 struct inode *inode = file_inode(file);
3104 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3105 struct btrfs_ioctl_vol_args *vol_args;
3106 int ret;
3107
3108 if (!capable(CAP_SYS_ADMIN))
3109 return -EPERM;
3110
3111 ret = mnt_want_write_file(file);
3112 if (ret)
3113 return ret;
3114
3115 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
3116 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3117 goto out_drop_write;
3118 }
3119
3120 vol_args = memdup_user(arg, sizeof(*vol_args));
3121 if (IS_ERR(vol_args)) {
3122 ret = PTR_ERR(vol_args);
3123 goto out;
3124 }
3125
3126 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3127 ret = btrfs_rm_device(fs_info, vol_args->name, 0);
3128
3129 if (!ret)
3130 btrfs_info(fs_info, "disk deleted %s", vol_args->name);
3131 kfree(vol_args);
3132out:
3133 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3134out_drop_write:
3135 mnt_drop_write_file(file);
3136
3137 return ret;
3138}
3139
3140static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,
3141 void __user *arg)
3142{
3143 struct btrfs_ioctl_fs_info_args *fi_args;
3144 struct btrfs_device *device;
3145 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
3146 int ret = 0;
3147
3148 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
3149 if (!fi_args)
3150 return -ENOMEM;
3151
3152 rcu_read_lock();
3153 fi_args->num_devices = fs_devices->num_devices;
3154
3155 list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
3156 if (device->devid > fi_args->max_id)
3157 fi_args->max_id = device->devid;
3158 }
3159 rcu_read_unlock();
3160
3161 memcpy(&fi_args->fsid, fs_devices->fsid, sizeof(fi_args->fsid));
3162 fi_args->nodesize = fs_info->nodesize;
3163 fi_args->sectorsize = fs_info->sectorsize;
3164 fi_args->clone_alignment = fs_info->sectorsize;
3165
3166 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
3167 ret = -EFAULT;
3168
3169 kfree(fi_args);
3170 return ret;
3171}
3172
3173static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,
3174 void __user *arg)
3175{
3176 struct btrfs_ioctl_dev_info_args *di_args;
3177 struct btrfs_device *dev;
3178 int ret = 0;
3179 char *s_uuid = NULL;
3180
3181 di_args = memdup_user(arg, sizeof(*di_args));
3182 if (IS_ERR(di_args))
3183 return PTR_ERR(di_args);
3184
3185 if (!btrfs_is_empty_uuid(di_args->uuid))
3186 s_uuid = di_args->uuid;
3187
3188 rcu_read_lock();
3189 dev = btrfs_find_device(fs_info->fs_devices, di_args->devid, s_uuid,
3190 NULL, true);
3191
3192 if (!dev) {
3193 ret = -ENODEV;
3194 goto out;
3195 }
3196
3197 di_args->devid = dev->devid;
3198 di_args->bytes_used = btrfs_device_get_bytes_used(dev);
3199 di_args->total_bytes = btrfs_device_get_total_bytes(dev);
3200 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
3201 if (dev->name) {
3202 strncpy(di_args->path, rcu_str_deref(dev->name),
3203 sizeof(di_args->path) - 1);
3204 di_args->path[sizeof(di_args->path) - 1] = 0;
3205 } else {
3206 di_args->path[0] = '\0';
3207 }
3208
3209out:
3210 rcu_read_unlock();
3211 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
3212 ret = -EFAULT;
3213
3214 kfree(di_args);
3215 return ret;
3216}
3217
3218static void btrfs_double_extent_unlock(struct inode *inode1, u64 loff1,
3219 struct inode *inode2, u64 loff2, u64 len)
3220{
3221 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
3222 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
3223}
3224
3225static void btrfs_double_extent_lock(struct inode *inode1, u64 loff1,
3226 struct inode *inode2, u64 loff2, u64 len)
3227{
3228 if (inode1 < inode2) {
3229 swap(inode1, inode2);
3230 swap(loff1, loff2);
3231 } else if (inode1 == inode2 && loff2 < loff1) {
3232 swap(loff1, loff2);
3233 }
3234 lock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
3235 lock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
3236}
3237
3238static int btrfs_extent_same_range(struct inode *src, u64 loff, u64 len,
3239 struct inode *dst, u64 dst_loff)
3240{
3241 int ret;
3242
3243 /*
3244 * Lock destination range to serialize with concurrent readpages() and
3245 * source range to serialize with relocation.
3246 */
3247 btrfs_double_extent_lock(src, loff, dst, dst_loff, len);
3248 ret = btrfs_clone(src, dst, loff, len, len, dst_loff, 1);
3249 btrfs_double_extent_unlock(src, loff, dst, dst_loff, len);
3250
3251 return ret;
3252}
3253
3254#define BTRFS_MAX_DEDUPE_LEN SZ_16M
3255
3256static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
3257 struct inode *dst, u64 dst_loff)
3258{
3259 int ret;
3260 u64 i, tail_len, chunk_count;
3261 struct btrfs_root *root_dst = BTRFS_I(dst)->root;
3262
3263 spin_lock(&root_dst->root_item_lock);
3264 if (root_dst->send_in_progress) {
3265 btrfs_warn_rl(root_dst->fs_info,
3266"cannot deduplicate to root %llu while send operations are using it (%d in progress)",
3267 root_dst->root_key.objectid,
3268 root_dst->send_in_progress);
3269 spin_unlock(&root_dst->root_item_lock);
3270 return -EAGAIN;
3271 }
3272 root_dst->dedupe_in_progress++;
3273 spin_unlock(&root_dst->root_item_lock);
3274
3275 tail_len = olen % BTRFS_MAX_DEDUPE_LEN;
3276 chunk_count = div_u64(olen, BTRFS_MAX_DEDUPE_LEN);
3277
3278 for (i = 0; i < chunk_count; i++) {
3279 ret = btrfs_extent_same_range(src, loff, BTRFS_MAX_DEDUPE_LEN,
3280 dst, dst_loff);
3281 if (ret)
3282 goto out;
3283
3284 loff += BTRFS_MAX_DEDUPE_LEN;
3285 dst_loff += BTRFS_MAX_DEDUPE_LEN;
3286 }
3287
3288 if (tail_len > 0)
3289 ret = btrfs_extent_same_range(src, loff, tail_len, dst,
3290 dst_loff);
3291out:
3292 spin_lock(&root_dst->root_item_lock);
3293 root_dst->dedupe_in_progress--;
3294 spin_unlock(&root_dst->root_item_lock);
3295
3296 return ret;
3297}
3298
3299static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3300 struct inode *inode,
3301 u64 endoff,
3302 const u64 destoff,
3303 const u64 olen,
3304 int no_time_update)
3305{
3306 struct btrfs_root *root = BTRFS_I(inode)->root;
3307 int ret;
3308
3309 inode_inc_iversion(inode);
3310 if (!no_time_update)
3311 inode->i_mtime = inode->i_ctime = current_time(inode);
3312 /*
3313 * We round up to the block size at eof when determining which
3314 * extents to clone above, but shouldn't round up the file size.
3315 */
3316 if (endoff > destoff + olen)
3317 endoff = destoff + olen;
3318 if (endoff > inode->i_size)
3319 btrfs_i_size_write(BTRFS_I(inode), endoff);
3320
3321 ret = btrfs_update_inode(trans, root, inode);
3322 if (ret) {
3323 btrfs_abort_transaction(trans, ret);
3324 btrfs_end_transaction(trans);
3325 goto out;
3326 }
3327 ret = btrfs_end_transaction(trans);
3328out:
3329 return ret;
3330}
3331
3332/*
3333 * Make sure we do not end up inserting an inline extent into a file that has
3334 * already other (non-inline) extents. If a file has an inline extent it can
3335 * not have any other extents and the (single) inline extent must start at the
3336 * file offset 0. Failing to respect these rules will lead to file corruption,
3337 * resulting in EIO errors on read/write operations, hitting BUG_ON's in mm, etc
3338 *
3339 * We can have extents that have been already written to disk or we can have
3340 * dirty ranges still in delalloc, in which case the extent maps and items are
3341 * created only when we run delalloc, and the delalloc ranges might fall outside
3342 * the range we are currently locking in the inode's io tree. So we check the
3343 * inode's i_size because of that (i_size updates are done while holding the
3344 * i_mutex, which we are holding here).
3345 * We also check to see if the inode has a size not greater than "datal" but has
3346 * extents beyond it, due to an fallocate with FALLOC_FL_KEEP_SIZE (and we are
3347 * protected against such concurrent fallocate calls by the i_mutex).
3348 *
3349 * If the file has no extents but a size greater than datal, do not allow the
3350 * copy because we would need turn the inline extent into a non-inline one (even
3351 * with NO_HOLES enabled). If we find our destination inode only has one inline
3352 * extent, just overwrite it with the source inline extent if its size is less
3353 * than the source extent's size, or we could copy the source inline extent's
3354 * data into the destination inode's inline extent if the later is greater then
3355 * the former.
3356 */
3357static int clone_copy_inline_extent(struct inode *dst,
3358 struct btrfs_trans_handle *trans,
3359 struct btrfs_path *path,
3360 struct btrfs_key *new_key,
3361 const u64 drop_start,
3362 const u64 datal,
3363 const u64 skip,
3364 const u64 size,
3365 char *inline_data)
3366{
3367 struct btrfs_fs_info *fs_info = btrfs_sb(dst->i_sb);
3368 struct btrfs_root *root = BTRFS_I(dst)->root;
3369 const u64 aligned_end = ALIGN(new_key->offset + datal,
3370 fs_info->sectorsize);
3371 int ret;
3372 struct btrfs_key key;
3373
3374 if (new_key->offset > 0)
3375 return -EOPNOTSUPP;
3376
3377 key.objectid = btrfs_ino(BTRFS_I(dst));
3378 key.type = BTRFS_EXTENT_DATA_KEY;
3379 key.offset = 0;
3380 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3381 if (ret < 0) {
3382 return ret;
3383 } else if (ret > 0) {
3384 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
3385 ret = btrfs_next_leaf(root, path);
3386 if (ret < 0)
3387 return ret;
3388 else if (ret > 0)
3389 goto copy_inline_extent;
3390 }
3391 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
3392 if (key.objectid == btrfs_ino(BTRFS_I(dst)) &&
3393 key.type == BTRFS_EXTENT_DATA_KEY) {
3394 ASSERT(key.offset > 0);
3395 return -EOPNOTSUPP;
3396 }
3397 } else if (i_size_read(dst) <= datal) {
3398 struct btrfs_file_extent_item *ei;
3399 u64 ext_len;
3400
3401 /*
3402 * If the file size is <= datal, make sure there are no other
3403 * extents following (can happen do to an fallocate call with
3404 * the flag FALLOC_FL_KEEP_SIZE).
3405 */
3406 ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
3407 struct btrfs_file_extent_item);
3408 /*
3409 * If it's an inline extent, it can not have other extents
3410 * following it.
3411 */
3412 if (btrfs_file_extent_type(path->nodes[0], ei) ==
3413 BTRFS_FILE_EXTENT_INLINE)
3414 goto copy_inline_extent;
3415
3416 ext_len = btrfs_file_extent_num_bytes(path->nodes[0], ei);
3417 if (ext_len > aligned_end)
3418 return -EOPNOTSUPP;
3419
3420 ret = btrfs_next_item(root, path);
3421 if (ret < 0) {
3422 return ret;
3423 } else if (ret == 0) {
3424 btrfs_item_key_to_cpu(path->nodes[0], &key,
3425 path->slots[0]);
3426 if (key.objectid == btrfs_ino(BTRFS_I(dst)) &&
3427 key.type == BTRFS_EXTENT_DATA_KEY)
3428 return -EOPNOTSUPP;
3429 }
3430 }
3431
3432copy_inline_extent:
3433 /*
3434 * We have no extent items, or we have an extent at offset 0 which may
3435 * or may not be inlined. All these cases are dealt the same way.
3436 */
3437 if (i_size_read(dst) > datal) {
3438 /*
3439 * If the destination inode has an inline extent...
3440 * This would require copying the data from the source inline
3441 * extent into the beginning of the destination's inline extent.
3442 * But this is really complex, both extents can be compressed
3443 * or just one of them, which would require decompressing and
3444 * re-compressing data (which could increase the new compressed
3445 * size, not allowing the compressed data to fit anymore in an
3446 * inline extent).
3447 * So just don't support this case for now (it should be rare,
3448 * we are not really saving space when cloning inline extents).
3449 */
3450 return -EOPNOTSUPP;
3451 }
3452
3453 btrfs_release_path(path);
3454 ret = btrfs_drop_extents(trans, root, dst, drop_start, aligned_end, 1);
3455 if (ret)
3456 return ret;
3457 ret = btrfs_insert_empty_item(trans, root, path, new_key, size);
3458 if (ret)
3459 return ret;
3460
3461 if (skip) {
3462 const u32 start = btrfs_file_extent_calc_inline_size(0);
3463
3464 memmove(inline_data + start, inline_data + start + skip, datal);
3465 }
3466
3467 write_extent_buffer(path->nodes[0], inline_data,
3468 btrfs_item_ptr_offset(path->nodes[0],
3469 path->slots[0]),
3470 size);
3471 inode_add_bytes(dst, datal);
3472 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(dst)->runtime_flags);
3473
3474 return 0;
3475}
3476
3477/**
3478 * btrfs_clone() - clone a range from inode file to another
3479 *
3480 * @src: Inode to clone from
3481 * @inode: Inode to clone to
3482 * @off: Offset within source to start clone from
3483 * @olen: Original length, passed by user, of range to clone
3484 * @olen_aligned: Block-aligned value of olen
3485 * @destoff: Offset within @inode to start clone
3486 * @no_time_update: Whether to update mtime/ctime on the target inode
3487 */
3488static int btrfs_clone(struct inode *src, struct inode *inode,
3489 const u64 off, const u64 olen, const u64 olen_aligned,
3490 const u64 destoff, int no_time_update)
3491{
3492 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3493 struct btrfs_root *root = BTRFS_I(inode)->root;
3494 struct btrfs_path *path = NULL;
3495 struct extent_buffer *leaf;
3496 struct btrfs_trans_handle *trans;
3497 char *buf = NULL;
3498 struct btrfs_key key;
3499 u32 nritems;
3500 int slot;
3501 int ret;
3502 const u64 len = olen_aligned;
3503 u64 last_dest_end = destoff;
3504
3505 ret = -ENOMEM;
3506 buf = kvmalloc(fs_info->nodesize, GFP_KERNEL);
3507 if (!buf)
3508 return ret;
3509
3510 path = btrfs_alloc_path();
3511 if (!path) {
3512 kvfree(buf);
3513 return ret;
3514 }
3515
3516 path->reada = READA_FORWARD;
3517 /* clone data */
3518 key.objectid = btrfs_ino(BTRFS_I(src));
3519 key.type = BTRFS_EXTENT_DATA_KEY;
3520 key.offset = off;
3521
3522 while (1) {
3523 u64 next_key_min_offset = key.offset + 1;
3524 struct btrfs_file_extent_item *extent;
3525 int type;
3526 u32 size;
3527 struct btrfs_key new_key;
3528 u64 disko = 0, diskl = 0;
3529 u64 datao = 0, datal = 0;
3530 u8 comp;
3531 u64 drop_start;
3532
3533 /*
3534 * note the key will change type as we walk through the
3535 * tree.
3536 */
3537 path->leave_spinning = 1;
3538 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3539 0, 0);
3540 if (ret < 0)
3541 goto out;
3542 /*
3543 * First search, if no extent item that starts at offset off was
3544 * found but the previous item is an extent item, it's possible
3545 * it might overlap our target range, therefore process it.
3546 */
3547 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3548 btrfs_item_key_to_cpu(path->nodes[0], &key,
3549 path->slots[0] - 1);
3550 if (key.type == BTRFS_EXTENT_DATA_KEY)
3551 path->slots[0]--;
3552 }
3553
3554 nritems = btrfs_header_nritems(path->nodes[0]);
3555process_slot:
3556 if (path->slots[0] >= nritems) {
3557 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3558 if (ret < 0)
3559 goto out;
3560 if (ret > 0)
3561 break;
3562 nritems = btrfs_header_nritems(path->nodes[0]);
3563 }
3564 leaf = path->nodes[0];
3565 slot = path->slots[0];
3566
3567 btrfs_item_key_to_cpu(leaf, &key, slot);
3568 if (key.type > BTRFS_EXTENT_DATA_KEY ||
3569 key.objectid != btrfs_ino(BTRFS_I(src)))
3570 break;
3571
3572 ASSERT(key.type == BTRFS_EXTENT_DATA_KEY);
3573
3574 extent = btrfs_item_ptr(leaf, slot,
3575 struct btrfs_file_extent_item);
3576 comp = btrfs_file_extent_compression(leaf, extent);
3577 type = btrfs_file_extent_type(leaf, extent);
3578 if (type == BTRFS_FILE_EXTENT_REG ||
3579 type == BTRFS_FILE_EXTENT_PREALLOC) {
3580 disko = btrfs_file_extent_disk_bytenr(leaf, extent);
3581 diskl = btrfs_file_extent_disk_num_bytes(leaf, extent);
3582 datao = btrfs_file_extent_offset(leaf, extent);
3583 datal = btrfs_file_extent_num_bytes(leaf, extent);
3584 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3585 /* Take upper bound, may be compressed */
3586 datal = btrfs_file_extent_ram_bytes(leaf, extent);
3587 }
3588
3589 /*
3590 * The first search might have left us at an extent item that
3591 * ends before our target range's start, can happen if we have
3592 * holes and NO_HOLES feature enabled.
3593 */
3594 if (key.offset + datal <= off) {
3595 path->slots[0]++;
3596 goto process_slot;
3597 } else if (key.offset >= off + len) {
3598 break;
3599 }
3600 next_key_min_offset = key.offset + datal;
3601 size = btrfs_item_size_nr(leaf, slot);
3602 read_extent_buffer(leaf, buf, btrfs_item_ptr_offset(leaf, slot),
3603 size);
3604
3605 btrfs_release_path(path);
3606 path->leave_spinning = 0;
3607
3608 memcpy(&new_key, &key, sizeof(new_key));
3609 new_key.objectid = btrfs_ino(BTRFS_I(inode));
3610 if (off <= key.offset)
3611 new_key.offset = key.offset + destoff - off;
3612 else
3613 new_key.offset = destoff;
3614
3615 /*
3616 * Deal with a hole that doesn't have an extent item that
3617 * represents it (NO_HOLES feature enabled).
3618 * This hole is either in the middle of the cloning range or at
3619 * the beginning (fully overlaps it or partially overlaps it).
3620 */
3621 if (new_key.offset != last_dest_end)
3622 drop_start = last_dest_end;
3623 else
3624 drop_start = new_key.offset;
3625
3626 if (type == BTRFS_FILE_EXTENT_REG ||
3627 type == BTRFS_FILE_EXTENT_PREALLOC) {
3628 struct btrfs_clone_extent_info clone_info;
3629
3630 /*
3631 * a | --- range to clone ---| b
3632 * | ------------- extent ------------- |
3633 */
3634
3635 /* Subtract range b */
3636 if (key.offset + datal > off + len)
3637 datal = off + len - key.offset;
3638
3639 /* Subtract range a */
3640 if (off > key.offset) {
3641 datao += off - key.offset;
3642 datal -= off - key.offset;
3643 }
3644
3645 clone_info.disk_offset = disko;
3646 clone_info.disk_len = diskl;
3647 clone_info.data_offset = datao;
3648 clone_info.data_len = datal;
3649 clone_info.file_offset = new_key.offset;
3650 clone_info.extent_buf = buf;
3651 clone_info.item_size = size;
3652 ret = btrfs_punch_hole_range(inode, path,
3653 drop_start,
3654 new_key.offset + datal - 1,
3655 &clone_info, &trans);
3656 if (ret)
3657 goto out;
3658 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3659 u64 skip = 0;
3660 u64 trim = 0;
3661
3662 if (off > key.offset) {
3663 skip = off - key.offset;
3664 new_key.offset += skip;
3665 }
3666
3667 if (key.offset + datal > off + len)
3668 trim = key.offset + datal - (off + len);
3669
3670 if (comp && (skip || trim)) {
3671 ret = -EINVAL;
3672 goto out;
3673 }
3674 size -= skip + trim;
3675 datal -= skip + trim;
3676
3677 /*
3678 * If our extent is inline, we know we will drop or
3679 * adjust at most 1 extent item in the destination root.
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 ret = clone_copy_inline_extent(inode, trans, path,
3692 &new_key, drop_start,
3693 datal, skip, size, buf);
3694 if (ret) {
3695 if (ret != -EOPNOTSUPP)
3696 btrfs_abort_transaction(trans, ret);
3697 btrfs_end_transaction(trans);
3698 goto out;
3699 }
3700 }
3701
3702 btrfs_release_path(path);
3703
3704 last_dest_end = ALIGN(new_key.offset + datal,
3705 fs_info->sectorsize);
3706 ret = clone_finish_inode_update(trans, inode, last_dest_end,
3707 destoff, olen, no_time_update);
3708 if (ret)
3709 goto out;
3710 if (new_key.offset + datal >= destoff + len)
3711 break;
3712
3713 btrfs_release_path(path);
3714 key.offset = next_key_min_offset;
3715
3716 if (fatal_signal_pending(current)) {
3717 ret = -EINTR;
3718 goto out;
3719 }
3720 }
3721 ret = 0;
3722
3723 if (last_dest_end < destoff + len) {
3724 struct btrfs_clone_extent_info clone_info = { 0 };
3725 /*
3726 * We have an implicit hole (NO_HOLES feature is enabled) that
3727 * fully or partially overlaps our cloning range at its end.
3728 */
3729 btrfs_release_path(path);
3730 path->leave_spinning = 0;
3731
3732 /*
3733 * We are dealing with a hole and our clone_info already has a
3734 * disk_offset of 0, we only need to fill the data length and
3735 * file offset.
3736 */
3737 clone_info.data_len = destoff + len - last_dest_end;
3738 clone_info.file_offset = last_dest_end;
3739 ret = btrfs_punch_hole_range(inode, path,
3740 last_dest_end, destoff + len - 1,
3741 &clone_info, &trans);
3742 if (ret)
3743 goto out;
3744
3745 ret = clone_finish_inode_update(trans, inode, destoff + len,
3746 destoff, olen, no_time_update);
3747 }
3748
3749out:
3750 btrfs_free_path(path);
3751 kvfree(buf);
3752 return ret;
3753}
3754
3755static noinline int btrfs_clone_files(struct file *file, struct file *file_src,
3756 u64 off, u64 olen, u64 destoff)
3757{
3758 struct inode *inode = file_inode(file);
3759 struct inode *src = file_inode(file_src);
3760 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3761 int ret;
3762 u64 len = olen;
3763 u64 bs = fs_info->sb->s_blocksize;
3764
3765 /*
3766 * TODO:
3767 * - split compressed inline extents. annoying: we need to
3768 * decompress into destination's address_space (the file offset
3769 * may change, so source mapping won't do), then recompress (or
3770 * otherwise reinsert) a subrange.
3771 *
3772 * - split destination inode's inline extents. The inline extents can
3773 * be either compressed or non-compressed.
3774 */
3775
3776 /*
3777 * VFS's generic_remap_file_range_prep() protects us from cloning the
3778 * eof block into the middle of a file, which would result in corruption
3779 * if the file size is not blocksize aligned. So we don't need to check
3780 * for that case here.
3781 */
3782 if (off + len == src->i_size)
3783 len = ALIGN(src->i_size, bs) - off;
3784
3785 if (destoff > inode->i_size) {
3786 const u64 wb_start = ALIGN_DOWN(inode->i_size, bs);
3787
3788 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3789 if (ret)
3790 return ret;
3791 /*
3792 * We may have truncated the last block if the inode's size is
3793 * not sector size aligned, so we need to wait for writeback to
3794 * complete before proceeding further, otherwise we can race
3795 * with cloning and attempt to increment a reference to an
3796 * extent that no longer exists (writeback completed right after
3797 * we found the previous extent covering eof and before we
3798 * attempted to increment its reference count).
3799 */
3800 ret = btrfs_wait_ordered_range(inode, wb_start,
3801 destoff - wb_start);
3802 if (ret)
3803 return ret;
3804 }
3805
3806 /*
3807 * Lock destination range to serialize with concurrent readpages() and
3808 * source range to serialize with relocation.
3809 */
3810 btrfs_double_extent_lock(src, off, inode, destoff, len);
3811 ret = btrfs_clone(src, inode, off, olen, len, destoff, 0);
3812 btrfs_double_extent_unlock(src, off, inode, destoff, len);
3813 /*
3814 * Truncate page cache pages so that future reads will see the cloned
3815 * data immediately and not the previous data.
3816 */
3817 truncate_inode_pages_range(&inode->i_data,
3818 round_down(destoff, PAGE_SIZE),
3819 round_up(destoff + len, PAGE_SIZE) - 1);
3820
3821 return ret;
3822}
3823
3824static int btrfs_remap_file_range_prep(struct file *file_in, loff_t pos_in,
3825 struct file *file_out, loff_t pos_out,
3826 loff_t *len, unsigned int remap_flags)
3827{
3828 struct inode *inode_in = file_inode(file_in);
3829 struct inode *inode_out = file_inode(file_out);
3830 u64 bs = BTRFS_I(inode_out)->root->fs_info->sb->s_blocksize;
3831 bool same_inode = inode_out == inode_in;
3832 u64 wb_len;
3833 int ret;
3834
3835 if (!(remap_flags & REMAP_FILE_DEDUP)) {
3836 struct btrfs_root *root_out = BTRFS_I(inode_out)->root;
3837
3838 if (btrfs_root_readonly(root_out))
3839 return -EROFS;
3840
3841 if (file_in->f_path.mnt != file_out->f_path.mnt ||
3842 inode_in->i_sb != inode_out->i_sb)
3843 return -EXDEV;
3844 }
3845
3846 /* don't make the dst file partly checksummed */
3847 if ((BTRFS_I(inode_in)->flags & BTRFS_INODE_NODATASUM) !=
3848 (BTRFS_I(inode_out)->flags & BTRFS_INODE_NODATASUM)) {
3849 return -EINVAL;
3850 }
3851
3852 /*
3853 * Now that the inodes are locked, we need to start writeback ourselves
3854 * and can not rely on the writeback from the VFS's generic helper
3855 * generic_remap_file_range_prep() because:
3856 *
3857 * 1) For compression we must call filemap_fdatawrite_range() range
3858 * twice (btrfs_fdatawrite_range() does it for us), and the generic
3859 * helper only calls it once;
3860 *
3861 * 2) filemap_fdatawrite_range(), called by the generic helper only
3862 * waits for the writeback to complete, i.e. for IO to be done, and
3863 * not for the ordered extents to complete. We need to wait for them
3864 * to complete so that new file extent items are in the fs tree.
3865 */
3866 if (*len == 0 && !(remap_flags & REMAP_FILE_DEDUP))
3867 wb_len = ALIGN(inode_in->i_size, bs) - ALIGN_DOWN(pos_in, bs);
3868 else
3869 wb_len = ALIGN(*len, bs);
3870
3871 /*
3872 * Since we don't lock ranges, wait for ongoing lockless dio writes (as
3873 * any in progress could create its ordered extents after we wait for
3874 * existing ordered extents below).
3875 */
3876 inode_dio_wait(inode_in);
3877 if (!same_inode)
3878 inode_dio_wait(inode_out);
3879
3880 /*
3881 * Workaround to make sure NOCOW buffered write reach disk as NOCOW.
3882 *
3883 * Btrfs' back references do not have a block level granularity, they
3884 * work at the whole extent level.
3885 * NOCOW buffered write without data space reserved may not be able
3886 * to fall back to CoW due to lack of data space, thus could cause
3887 * data loss.
3888 *
3889 * Here we take a shortcut by flushing the whole inode, so that all
3890 * nocow write should reach disk as nocow before we increase the
3891 * reference of the extent. We could do better by only flushing NOCOW
3892 * data, but that needs extra accounting.
3893 *
3894 * Also we don't need to check ASYNC_EXTENT, as async extent will be
3895 * CoWed anyway, not affecting nocow part.
3896 */
3897 ret = filemap_flush(inode_in->i_mapping);
3898 if (ret < 0)
3899 return ret;
3900
3901 ret = btrfs_wait_ordered_range(inode_in, ALIGN_DOWN(pos_in, bs),
3902 wb_len);
3903 if (ret < 0)
3904 return ret;
3905 ret = btrfs_wait_ordered_range(inode_out, ALIGN_DOWN(pos_out, bs),
3906 wb_len);
3907 if (ret < 0)
3908 return ret;
3909
3910 return generic_remap_file_range_prep(file_in, pos_in, file_out, pos_out,
3911 len, remap_flags);
3912}
3913
3914loff_t btrfs_remap_file_range(struct file *src_file, loff_t off,
3915 struct file *dst_file, loff_t destoff, loff_t len,
3916 unsigned int remap_flags)
3917{
3918 struct inode *src_inode = file_inode(src_file);
3919 struct inode *dst_inode = file_inode(dst_file);
3920 bool same_inode = dst_inode == src_inode;
3921 int ret;
3922
3923 if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY))
3924 return -EINVAL;
3925
3926 if (same_inode)
3927 inode_lock(src_inode);
3928 else
3929 lock_two_nondirectories(src_inode, dst_inode);
3930
3931 ret = btrfs_remap_file_range_prep(src_file, off, dst_file, destoff,
3932 &len, remap_flags);
3933 if (ret < 0 || len == 0)
3934 goto out_unlock;
3935
3936 if (remap_flags & REMAP_FILE_DEDUP)
3937 ret = btrfs_extent_same(src_inode, off, len, dst_inode, destoff);
3938 else
3939 ret = btrfs_clone_files(dst_file, src_file, off, len, destoff);
3940
3941out_unlock:
3942 if (same_inode)
3943 inode_unlock(src_inode);
3944 else
3945 unlock_two_nondirectories(src_inode, dst_inode);
3946
3947 return ret < 0 ? ret : len;
3948}
3949
3950static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3951{
3952 struct inode *inode = file_inode(file);
3953 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3954 struct btrfs_root *root = BTRFS_I(inode)->root;
3955 struct btrfs_root *new_root;
3956 struct btrfs_dir_item *di;
3957 struct btrfs_trans_handle *trans;
3958 struct btrfs_path *path;
3959 struct btrfs_key location;
3960 struct btrfs_disk_key disk_key;
3961 u64 objectid = 0;
3962 u64 dir_id;
3963 int ret;
3964
3965 if (!capable(CAP_SYS_ADMIN))
3966 return -EPERM;
3967
3968 ret = mnt_want_write_file(file);
3969 if (ret)
3970 return ret;
3971
3972 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3973 ret = -EFAULT;
3974 goto out;
3975 }
3976
3977 if (!objectid)
3978 objectid = BTRFS_FS_TREE_OBJECTID;
3979
3980 location.objectid = objectid;
3981 location.type = BTRFS_ROOT_ITEM_KEY;
3982 location.offset = (u64)-1;
3983
3984 new_root = btrfs_read_fs_root_no_name(fs_info, &location);
3985 if (IS_ERR(new_root)) {
3986 ret = PTR_ERR(new_root);
3987 goto out;
3988 }
3989 if (!is_fstree(new_root->root_key.objectid)) {
3990 ret = -ENOENT;
3991 goto out;
3992 }
3993
3994 path = btrfs_alloc_path();
3995 if (!path) {
3996 ret = -ENOMEM;
3997 goto out;
3998 }
3999 path->leave_spinning = 1;
4000
4001 trans = btrfs_start_transaction(root, 1);
4002 if (IS_ERR(trans)) {
4003 btrfs_free_path(path);
4004 ret = PTR_ERR(trans);
4005 goto out;
4006 }
4007
4008 dir_id = btrfs_super_root_dir(fs_info->super_copy);
4009 di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
4010 dir_id, "default", 7, 1);
4011 if (IS_ERR_OR_NULL(di)) {
4012 btrfs_free_path(path);
4013 btrfs_end_transaction(trans);
4014 btrfs_err(fs_info,
4015 "Umm, you don't have the default diritem, this isn't going to work");
4016 ret = -ENOENT;
4017 goto out;
4018 }
4019
4020 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
4021 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
4022 btrfs_mark_buffer_dirty(path->nodes[0]);
4023 btrfs_free_path(path);
4024
4025 btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
4026 btrfs_end_transaction(trans);
4027out:
4028 mnt_drop_write_file(file);
4029 return ret;
4030}
4031
4032static void get_block_group_info(struct list_head *groups_list,
4033 struct btrfs_ioctl_space_info *space)
4034{
4035 struct btrfs_block_group_cache *block_group;
4036
4037 space->total_bytes = 0;
4038 space->used_bytes = 0;
4039 space->flags = 0;
4040 list_for_each_entry(block_group, groups_list, list) {
4041 space->flags = block_group->flags;
4042 space->total_bytes += block_group->key.offset;
4043 space->used_bytes +=
4044 btrfs_block_group_used(&block_group->item);
4045 }
4046}
4047
4048static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
4049 void __user *arg)
4050{
4051 struct btrfs_ioctl_space_args space_args;
4052 struct btrfs_ioctl_space_info space;
4053 struct btrfs_ioctl_space_info *dest;
4054 struct btrfs_ioctl_space_info *dest_orig;
4055 struct btrfs_ioctl_space_info __user *user_dest;
4056 struct btrfs_space_info *info;
4057 static const u64 types[] = {
4058 BTRFS_BLOCK_GROUP_DATA,
4059 BTRFS_BLOCK_GROUP_SYSTEM,
4060 BTRFS_BLOCK_GROUP_METADATA,
4061 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA
4062 };
4063 int num_types = 4;
4064 int alloc_size;
4065 int ret = 0;
4066 u64 slot_count = 0;
4067 int i, c;
4068
4069 if (copy_from_user(&space_args,
4070 (struct btrfs_ioctl_space_args __user *)arg,
4071 sizeof(space_args)))
4072 return -EFAULT;
4073
4074 for (i = 0; i < num_types; i++) {
4075 struct btrfs_space_info *tmp;
4076
4077 info = NULL;
4078 rcu_read_lock();
4079 list_for_each_entry_rcu(tmp, &fs_info->space_info,
4080 list) {
4081 if (tmp->flags == types[i]) {
4082 info = tmp;
4083 break;
4084 }
4085 }
4086 rcu_read_unlock();
4087
4088 if (!info)
4089 continue;
4090
4091 down_read(&info->groups_sem);
4092 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4093 if (!list_empty(&info->block_groups[c]))
4094 slot_count++;
4095 }
4096 up_read(&info->groups_sem);
4097 }
4098
4099 /*
4100 * Global block reserve, exported as a space_info
4101 */
4102 slot_count++;
4103
4104 /* space_slots == 0 means they are asking for a count */
4105 if (space_args.space_slots == 0) {
4106 space_args.total_spaces = slot_count;
4107 goto out;
4108 }
4109
4110 slot_count = min_t(u64, space_args.space_slots, slot_count);
4111
4112 alloc_size = sizeof(*dest) * slot_count;
4113
4114 /* we generally have at most 6 or so space infos, one for each raid
4115 * level. So, a whole page should be more than enough for everyone
4116 */
4117 if (alloc_size > PAGE_SIZE)
4118 return -ENOMEM;
4119
4120 space_args.total_spaces = 0;
4121 dest = kmalloc(alloc_size, GFP_KERNEL);
4122 if (!dest)
4123 return -ENOMEM;
4124 dest_orig = dest;
4125
4126 /* now we have a buffer to copy into */
4127 for (i = 0; i < num_types; i++) {
4128 struct btrfs_space_info *tmp;
4129
4130 if (!slot_count)
4131 break;
4132
4133 info = NULL;
4134 rcu_read_lock();
4135 list_for_each_entry_rcu(tmp, &fs_info->space_info,
4136 list) {
4137 if (tmp->flags == types[i]) {
4138 info = tmp;
4139 break;
4140 }
4141 }
4142 rcu_read_unlock();
4143
4144 if (!info)
4145 continue;
4146 down_read(&info->groups_sem);
4147 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4148 if (!list_empty(&info->block_groups[c])) {
4149 get_block_group_info(&info->block_groups[c],
4150 &space);
4151 memcpy(dest, &space, sizeof(space));
4152 dest++;
4153 space_args.total_spaces++;
4154 slot_count--;
4155 }
4156 if (!slot_count)
4157 break;
4158 }
4159 up_read(&info->groups_sem);
4160 }
4161
4162 /*
4163 * Add global block reserve
4164 */
4165 if (slot_count) {
4166 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
4167
4168 spin_lock(&block_rsv->lock);
4169 space.total_bytes = block_rsv->size;
4170 space.used_bytes = block_rsv->size - block_rsv->reserved;
4171 spin_unlock(&block_rsv->lock);
4172 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
4173 memcpy(dest, &space, sizeof(space));
4174 space_args.total_spaces++;
4175 }
4176
4177 user_dest = (struct btrfs_ioctl_space_info __user *)
4178 (arg + sizeof(struct btrfs_ioctl_space_args));
4179
4180 if (copy_to_user(user_dest, dest_orig, alloc_size))
4181 ret = -EFAULT;
4182
4183 kfree(dest_orig);
4184out:
4185 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4186 ret = -EFAULT;
4187
4188 return ret;
4189}
4190
4191static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4192 void __user *argp)
4193{
4194 struct btrfs_trans_handle *trans;
4195 u64 transid;
4196 int ret;
4197
4198 trans = btrfs_attach_transaction_barrier(root);
4199 if (IS_ERR(trans)) {
4200 if (PTR_ERR(trans) != -ENOENT)
4201 return PTR_ERR(trans);
4202
4203 /* No running transaction, don't bother */
4204 transid = root->fs_info->last_trans_committed;
4205 goto out;
4206 }
4207 transid = trans->transid;
4208 ret = btrfs_commit_transaction_async(trans, 0);
4209 if (ret) {
4210 btrfs_end_transaction(trans);
4211 return ret;
4212 }
4213out:
4214 if (argp)
4215 if (copy_to_user(argp, &transid, sizeof(transid)))
4216 return -EFAULT;
4217 return 0;
4218}
4219
4220static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,
4221 void __user *argp)
4222{
4223 u64 transid;
4224
4225 if (argp) {
4226 if (copy_from_user(&transid, argp, sizeof(transid)))
4227 return -EFAULT;
4228 } else {
4229 transid = 0; /* current trans */
4230 }
4231 return btrfs_wait_for_commit(fs_info, transid);
4232}
4233
4234static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4235{
4236 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
4237 struct btrfs_ioctl_scrub_args *sa;
4238 int ret;
4239
4240 if (!capable(CAP_SYS_ADMIN))
4241 return -EPERM;
4242
4243 sa = memdup_user(arg, sizeof(*sa));
4244 if (IS_ERR(sa))
4245 return PTR_ERR(sa);
4246
4247 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4248 ret = mnt_want_write_file(file);
4249 if (ret)
4250 goto out;
4251 }
4252
4253 ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,
4254 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4255 0);
4256
4257 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
4258 ret = -EFAULT;
4259
4260 if (!(sa->flags & BTRFS_SCRUB_READONLY))
4261 mnt_drop_write_file(file);
4262out:
4263 kfree(sa);
4264 return ret;
4265}
4266
4267static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)
4268{
4269 if (!capable(CAP_SYS_ADMIN))
4270 return -EPERM;
4271
4272 return btrfs_scrub_cancel(fs_info);
4273}
4274
4275static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
4276 void __user *arg)
4277{
4278 struct btrfs_ioctl_scrub_args *sa;
4279 int ret;
4280
4281 if (!capable(CAP_SYS_ADMIN))
4282 return -EPERM;
4283
4284 sa = memdup_user(arg, sizeof(*sa));
4285 if (IS_ERR(sa))
4286 return PTR_ERR(sa);
4287
4288 ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
4289
4290 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
4291 ret = -EFAULT;
4292
4293 kfree(sa);
4294 return ret;
4295}
4296
4297static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
4298 void __user *arg)
4299{
4300 struct btrfs_ioctl_get_dev_stats *sa;
4301 int ret;
4302
4303 sa = memdup_user(arg, sizeof(*sa));
4304 if (IS_ERR(sa))
4305 return PTR_ERR(sa);
4306
4307 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4308 kfree(sa);
4309 return -EPERM;
4310 }
4311
4312 ret = btrfs_get_dev_stats(fs_info, sa);
4313
4314 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
4315 ret = -EFAULT;
4316
4317 kfree(sa);
4318 return ret;
4319}
4320
4321static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
4322 void __user *arg)
4323{
4324 struct btrfs_ioctl_dev_replace_args *p;
4325 int ret;
4326
4327 if (!capable(CAP_SYS_ADMIN))
4328 return -EPERM;
4329
4330 p = memdup_user(arg, sizeof(*p));
4331 if (IS_ERR(p))
4332 return PTR_ERR(p);
4333
4334 switch (p->cmd) {
4335 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4336 if (sb_rdonly(fs_info->sb)) {
4337 ret = -EROFS;
4338 goto out;
4339 }
4340 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
4341 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4342 } else {
4343 ret = btrfs_dev_replace_by_ioctl(fs_info, p);
4344 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
4345 }
4346 break;
4347 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4348 btrfs_dev_replace_status(fs_info, p);
4349 ret = 0;
4350 break;
4351 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4352 p->result = btrfs_dev_replace_cancel(fs_info);
4353 ret = 0;
4354 break;
4355 default:
4356 ret = -EINVAL;
4357 break;
4358 }
4359
4360 if ((ret == 0 || ret == -ECANCELED) && copy_to_user(arg, p, sizeof(*p)))
4361 ret = -EFAULT;
4362out:
4363 kfree(p);
4364 return ret;
4365}
4366
4367static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4368{
4369 int ret = 0;
4370 int i;
4371 u64 rel_ptr;
4372 int size;
4373 struct btrfs_ioctl_ino_path_args *ipa = NULL;
4374 struct inode_fs_paths *ipath = NULL;
4375 struct btrfs_path *path;
4376
4377 if (!capable(CAP_DAC_READ_SEARCH))
4378 return -EPERM;
4379
4380 path = btrfs_alloc_path();
4381 if (!path) {
4382 ret = -ENOMEM;
4383 goto out;
4384 }
4385
4386 ipa = memdup_user(arg, sizeof(*ipa));
4387 if (IS_ERR(ipa)) {
4388 ret = PTR_ERR(ipa);
4389 ipa = NULL;
4390 goto out;
4391 }
4392
4393 size = min_t(u32, ipa->size, 4096);
4394 ipath = init_ipath(size, root, path);
4395 if (IS_ERR(ipath)) {
4396 ret = PTR_ERR(ipath);
4397 ipath = NULL;
4398 goto out;
4399 }
4400
4401 ret = paths_from_inode(ipa->inum, ipath);
4402 if (ret < 0)
4403 goto out;
4404
4405 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4406 rel_ptr = ipath->fspath->val[i] -
4407 (u64)(unsigned long)ipath->fspath->val;
4408 ipath->fspath->val[i] = rel_ptr;
4409 }
4410
4411 ret = copy_to_user((void __user *)(unsigned long)ipa->fspath,
4412 ipath->fspath, size);
4413 if (ret) {
4414 ret = -EFAULT;
4415 goto out;
4416 }
4417
4418out:
4419 btrfs_free_path(path);
4420 free_ipath(ipath);
4421 kfree(ipa);
4422
4423 return ret;
4424}
4425
4426static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4427{
4428 struct btrfs_data_container *inodes = ctx;
4429 const size_t c = 3 * sizeof(u64);
4430
4431 if (inodes->bytes_left >= c) {
4432 inodes->bytes_left -= c;
4433 inodes->val[inodes->elem_cnt] = inum;
4434 inodes->val[inodes->elem_cnt + 1] = offset;
4435 inodes->val[inodes->elem_cnt + 2] = root;
4436 inodes->elem_cnt += 3;
4437 } else {
4438 inodes->bytes_missing += c - inodes->bytes_left;
4439 inodes->bytes_left = 0;
4440 inodes->elem_missed += 3;
4441 }
4442
4443 return 0;
4444}
4445
4446static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,
4447 void __user *arg, int version)
4448{
4449 int ret = 0;
4450 int size;
4451 struct btrfs_ioctl_logical_ino_args *loi;
4452 struct btrfs_data_container *inodes = NULL;
4453 struct btrfs_path *path = NULL;
4454 bool ignore_offset;
4455
4456 if (!capable(CAP_SYS_ADMIN))
4457 return -EPERM;
4458
4459 loi = memdup_user(arg, sizeof(*loi));
4460 if (IS_ERR(loi))
4461 return PTR_ERR(loi);
4462
4463 if (version == 1) {
4464 ignore_offset = false;
4465 size = min_t(u32, loi->size, SZ_64K);
4466 } else {
4467 /* All reserved bits must be 0 for now */
4468 if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) {
4469 ret = -EINVAL;
4470 goto out_loi;
4471 }
4472 /* Only accept flags we have defined so far */
4473 if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) {
4474 ret = -EINVAL;
4475 goto out_loi;
4476 }
4477 ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET;
4478 size = min_t(u32, loi->size, SZ_16M);
4479 }
4480
4481 path = btrfs_alloc_path();
4482 if (!path) {
4483 ret = -ENOMEM;
4484 goto out;
4485 }
4486
4487 inodes = init_data_container(size);
4488 if (IS_ERR(inodes)) {
4489 ret = PTR_ERR(inodes);
4490 inodes = NULL;
4491 goto out;
4492 }
4493
4494 ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
4495 build_ino_list, inodes, ignore_offset);
4496 if (ret == -EINVAL)
4497 ret = -ENOENT;
4498 if (ret < 0)
4499 goto out;
4500
4501 ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes,
4502 size);
4503 if (ret)
4504 ret = -EFAULT;
4505
4506out:
4507 btrfs_free_path(path);
4508 kvfree(inodes);
4509out_loi:
4510 kfree(loi);
4511
4512 return ret;
4513}
4514
4515void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info,
4516 struct btrfs_ioctl_balance_args *bargs)
4517{
4518 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4519
4520 bargs->flags = bctl->flags;
4521
4522 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags))
4523 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4524 if (atomic_read(&fs_info->balance_pause_req))
4525 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4526 if (atomic_read(&fs_info->balance_cancel_req))
4527 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4528
4529 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4530 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4531 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4532
4533 spin_lock(&fs_info->balance_lock);
4534 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4535 spin_unlock(&fs_info->balance_lock);
4536}
4537
4538static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4539{
4540 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4541 struct btrfs_fs_info *fs_info = root->fs_info;
4542 struct btrfs_ioctl_balance_args *bargs;
4543 struct btrfs_balance_control *bctl;
4544 bool need_unlock; /* for mut. excl. ops lock */
4545 int ret;
4546
4547 if (!capable(CAP_SYS_ADMIN))
4548 return -EPERM;
4549
4550 ret = mnt_want_write_file(file);
4551 if (ret)
4552 return ret;
4553
4554again:
4555 if (!test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
4556 mutex_lock(&fs_info->balance_mutex);
4557 need_unlock = true;
4558 goto locked;
4559 }
4560
4561 /*
4562 * mut. excl. ops lock is locked. Three possibilities:
4563 * (1) some other op is running
4564 * (2) balance is running
4565 * (3) balance is paused -- special case (think resume)
4566 */
4567 mutex_lock(&fs_info->balance_mutex);
4568 if (fs_info->balance_ctl) {
4569 /* this is either (2) or (3) */
4570 if (!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4571 mutex_unlock(&fs_info->balance_mutex);
4572 /*
4573 * Lock released to allow other waiters to continue,
4574 * we'll reexamine the status again.
4575 */
4576 mutex_lock(&fs_info->balance_mutex);
4577
4578 if (fs_info->balance_ctl &&
4579 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4580 /* this is (3) */
4581 need_unlock = false;
4582 goto locked;
4583 }
4584
4585 mutex_unlock(&fs_info->balance_mutex);
4586 goto again;
4587 } else {
4588 /* this is (2) */
4589 mutex_unlock(&fs_info->balance_mutex);
4590 ret = -EINPROGRESS;
4591 goto out;
4592 }
4593 } else {
4594 /* this is (1) */
4595 mutex_unlock(&fs_info->balance_mutex);
4596 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4597 goto out;
4598 }
4599
4600locked:
4601 BUG_ON(!test_bit(BTRFS_FS_EXCL_OP, &fs_info->flags));
4602
4603 if (arg) {
4604 bargs = memdup_user(arg, sizeof(*bargs));
4605 if (IS_ERR(bargs)) {
4606 ret = PTR_ERR(bargs);
4607 goto out_unlock;
4608 }
4609
4610 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4611 if (!fs_info->balance_ctl) {
4612 ret = -ENOTCONN;
4613 goto out_bargs;
4614 }
4615
4616 bctl = fs_info->balance_ctl;
4617 spin_lock(&fs_info->balance_lock);
4618 bctl->flags |= BTRFS_BALANCE_RESUME;
4619 spin_unlock(&fs_info->balance_lock);
4620
4621 goto do_balance;
4622 }
4623 } else {
4624 bargs = NULL;
4625 }
4626
4627 if (fs_info->balance_ctl) {
4628 ret = -EINPROGRESS;
4629 goto out_bargs;
4630 }
4631
4632 bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
4633 if (!bctl) {
4634 ret = -ENOMEM;
4635 goto out_bargs;
4636 }
4637
4638 if (arg) {
4639 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4640 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4641 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4642
4643 bctl->flags = bargs->flags;
4644 } else {
4645 /* balance everything - no filters */
4646 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4647 }
4648
4649 if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
4650 ret = -EINVAL;
4651 goto out_bctl;
4652 }
4653
4654do_balance:
4655 /*
4656 * Ownership of bctl and filesystem flag BTRFS_FS_EXCL_OP goes to
4657 * btrfs_balance. bctl is freed in reset_balance_state, or, if
4658 * restriper was paused all the way until unmount, in free_fs_info.
4659 * The flag should be cleared after reset_balance_state.
4660 */
4661 need_unlock = false;
4662
4663 ret = btrfs_balance(fs_info, bctl, bargs);
4664 bctl = NULL;
4665
4666 if ((ret == 0 || ret == -ECANCELED) && arg) {
4667 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4668 ret = -EFAULT;
4669 }
4670
4671out_bctl:
4672 kfree(bctl);
4673out_bargs:
4674 kfree(bargs);
4675out_unlock:
4676 mutex_unlock(&fs_info->balance_mutex);
4677 if (need_unlock)
4678 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
4679out:
4680 mnt_drop_write_file(file);
4681 return ret;
4682}
4683
4684static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
4685{
4686 if (!capable(CAP_SYS_ADMIN))
4687 return -EPERM;
4688
4689 switch (cmd) {
4690 case BTRFS_BALANCE_CTL_PAUSE:
4691 return btrfs_pause_balance(fs_info);
4692 case BTRFS_BALANCE_CTL_CANCEL:
4693 return btrfs_cancel_balance(fs_info);
4694 }
4695
4696 return -EINVAL;
4697}
4698
4699static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
4700 void __user *arg)
4701{
4702 struct btrfs_ioctl_balance_args *bargs;
4703 int ret = 0;
4704
4705 if (!capable(CAP_SYS_ADMIN))
4706 return -EPERM;
4707
4708 mutex_lock(&fs_info->balance_mutex);
4709 if (!fs_info->balance_ctl) {
4710 ret = -ENOTCONN;
4711 goto out;
4712 }
4713
4714 bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
4715 if (!bargs) {
4716 ret = -ENOMEM;
4717 goto out;
4718 }
4719
4720 btrfs_update_ioctl_balance_args(fs_info, bargs);
4721
4722 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4723 ret = -EFAULT;
4724
4725 kfree(bargs);
4726out:
4727 mutex_unlock(&fs_info->balance_mutex);
4728 return ret;
4729}
4730
4731static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4732{
4733 struct inode *inode = file_inode(file);
4734 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4735 struct btrfs_ioctl_quota_ctl_args *sa;
4736 int ret;
4737
4738 if (!capable(CAP_SYS_ADMIN))
4739 return -EPERM;
4740
4741 ret = mnt_want_write_file(file);
4742 if (ret)
4743 return ret;
4744
4745 sa = memdup_user(arg, sizeof(*sa));
4746 if (IS_ERR(sa)) {
4747 ret = PTR_ERR(sa);
4748 goto drop_write;
4749 }
4750
4751 down_write(&fs_info->subvol_sem);
4752
4753 switch (sa->cmd) {
4754 case BTRFS_QUOTA_CTL_ENABLE:
4755 ret = btrfs_quota_enable(fs_info);
4756 break;
4757 case BTRFS_QUOTA_CTL_DISABLE:
4758 ret = btrfs_quota_disable(fs_info);
4759 break;
4760 default:
4761 ret = -EINVAL;
4762 break;
4763 }
4764
4765 kfree(sa);
4766 up_write(&fs_info->subvol_sem);
4767drop_write:
4768 mnt_drop_write_file(file);
4769 return ret;
4770}
4771
4772static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4773{
4774 struct inode *inode = file_inode(file);
4775 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4776 struct btrfs_root *root = BTRFS_I(inode)->root;
4777 struct btrfs_ioctl_qgroup_assign_args *sa;
4778 struct btrfs_trans_handle *trans;
4779 int ret;
4780 int err;
4781
4782 if (!capable(CAP_SYS_ADMIN))
4783 return -EPERM;
4784
4785 ret = mnt_want_write_file(file);
4786 if (ret)
4787 return ret;
4788
4789 sa = memdup_user(arg, sizeof(*sa));
4790 if (IS_ERR(sa)) {
4791 ret = PTR_ERR(sa);
4792 goto drop_write;
4793 }
4794
4795 trans = btrfs_join_transaction(root);
4796 if (IS_ERR(trans)) {
4797 ret = PTR_ERR(trans);
4798 goto out;
4799 }
4800
4801 if (sa->assign) {
4802 ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst);
4803 } else {
4804 ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst);
4805 }
4806
4807 /* update qgroup status and info */
4808 err = btrfs_run_qgroups(trans);
4809 if (err < 0)
4810 btrfs_handle_fs_error(fs_info, err,
4811 "failed to update qgroup status and info");
4812 err = btrfs_end_transaction(trans);
4813 if (err && !ret)
4814 ret = err;
4815
4816out:
4817 kfree(sa);
4818drop_write:
4819 mnt_drop_write_file(file);
4820 return ret;
4821}
4822
4823static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4824{
4825 struct inode *inode = file_inode(file);
4826 struct btrfs_root *root = BTRFS_I(inode)->root;
4827 struct btrfs_ioctl_qgroup_create_args *sa;
4828 struct btrfs_trans_handle *trans;
4829 int ret;
4830 int err;
4831
4832 if (!capable(CAP_SYS_ADMIN))
4833 return -EPERM;
4834
4835 ret = mnt_want_write_file(file);
4836 if (ret)
4837 return ret;
4838
4839 sa = memdup_user(arg, sizeof(*sa));
4840 if (IS_ERR(sa)) {
4841 ret = PTR_ERR(sa);
4842 goto drop_write;
4843 }
4844
4845 if (!sa->qgroupid) {
4846 ret = -EINVAL;
4847 goto out;
4848 }
4849
4850 trans = btrfs_join_transaction(root);
4851 if (IS_ERR(trans)) {
4852 ret = PTR_ERR(trans);
4853 goto out;
4854 }
4855
4856 if (sa->create) {
4857 ret = btrfs_create_qgroup(trans, sa->qgroupid);
4858 } else {
4859 ret = btrfs_remove_qgroup(trans, sa->qgroupid);
4860 }
4861
4862 err = btrfs_end_transaction(trans);
4863 if (err && !ret)
4864 ret = err;
4865
4866out:
4867 kfree(sa);
4868drop_write:
4869 mnt_drop_write_file(file);
4870 return ret;
4871}
4872
4873static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4874{
4875 struct inode *inode = file_inode(file);
4876 struct btrfs_root *root = BTRFS_I(inode)->root;
4877 struct btrfs_ioctl_qgroup_limit_args *sa;
4878 struct btrfs_trans_handle *trans;
4879 int ret;
4880 int err;
4881 u64 qgroupid;
4882
4883 if (!capable(CAP_SYS_ADMIN))
4884 return -EPERM;
4885
4886 ret = mnt_want_write_file(file);
4887 if (ret)
4888 return ret;
4889
4890 sa = memdup_user(arg, sizeof(*sa));
4891 if (IS_ERR(sa)) {
4892 ret = PTR_ERR(sa);
4893 goto drop_write;
4894 }
4895
4896 trans = btrfs_join_transaction(root);
4897 if (IS_ERR(trans)) {
4898 ret = PTR_ERR(trans);
4899 goto out;
4900 }
4901
4902 qgroupid = sa->qgroupid;
4903 if (!qgroupid) {
4904 /* take the current subvol as qgroup */
4905 qgroupid = root->root_key.objectid;
4906 }
4907
4908 ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim);
4909
4910 err = btrfs_end_transaction(trans);
4911 if (err && !ret)
4912 ret = err;
4913
4914out:
4915 kfree(sa);
4916drop_write:
4917 mnt_drop_write_file(file);
4918 return ret;
4919}
4920
4921static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4922{
4923 struct inode *inode = file_inode(file);
4924 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4925 struct btrfs_ioctl_quota_rescan_args *qsa;
4926 int ret;
4927
4928 if (!capable(CAP_SYS_ADMIN))
4929 return -EPERM;
4930
4931 ret = mnt_want_write_file(file);
4932 if (ret)
4933 return ret;
4934
4935 qsa = memdup_user(arg, sizeof(*qsa));
4936 if (IS_ERR(qsa)) {
4937 ret = PTR_ERR(qsa);
4938 goto drop_write;
4939 }
4940
4941 if (qsa->flags) {
4942 ret = -EINVAL;
4943 goto out;
4944 }
4945
4946 ret = btrfs_qgroup_rescan(fs_info);
4947
4948out:
4949 kfree(qsa);
4950drop_write:
4951 mnt_drop_write_file(file);
4952 return ret;
4953}
4954
4955static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
4956{
4957 struct inode *inode = file_inode(file);
4958 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4959 struct btrfs_ioctl_quota_rescan_args *qsa;
4960 int ret = 0;
4961
4962 if (!capable(CAP_SYS_ADMIN))
4963 return -EPERM;
4964
4965 qsa = kzalloc(sizeof(*qsa), GFP_KERNEL);
4966 if (!qsa)
4967 return -ENOMEM;
4968
4969 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4970 qsa->flags = 1;
4971 qsa->progress = fs_info->qgroup_rescan_progress.objectid;
4972 }
4973
4974 if (copy_to_user(arg, qsa, sizeof(*qsa)))
4975 ret = -EFAULT;
4976
4977 kfree(qsa);
4978 return ret;
4979}
4980
4981static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
4982{
4983 struct inode *inode = file_inode(file);
4984 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4985
4986 if (!capable(CAP_SYS_ADMIN))
4987 return -EPERM;
4988
4989 return btrfs_qgroup_wait_for_completion(fs_info, true);
4990}
4991
4992static long _btrfs_ioctl_set_received_subvol(struct file *file,
4993 struct btrfs_ioctl_received_subvol_args *sa)
4994{
4995 struct inode *inode = file_inode(file);
4996 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4997 struct btrfs_root *root = BTRFS_I(inode)->root;
4998 struct btrfs_root_item *root_item = &root->root_item;
4999 struct btrfs_trans_handle *trans;
5000 struct timespec64 ct = current_time(inode);
5001 int ret = 0;
5002 int received_uuid_changed;
5003
5004 if (!inode_owner_or_capable(inode))
5005 return -EPERM;
5006
5007 ret = mnt_want_write_file(file);
5008 if (ret < 0)
5009 return ret;
5010
5011 down_write(&fs_info->subvol_sem);
5012
5013 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
5014 ret = -EINVAL;
5015 goto out;
5016 }
5017
5018 if (btrfs_root_readonly(root)) {
5019 ret = -EROFS;
5020 goto out;
5021 }
5022
5023 /*
5024 * 1 - root item
5025 * 2 - uuid items (received uuid + subvol uuid)
5026 */
5027 trans = btrfs_start_transaction(root, 3);
5028 if (IS_ERR(trans)) {
5029 ret = PTR_ERR(trans);
5030 trans = NULL;
5031 goto out;
5032 }
5033
5034 sa->rtransid = trans->transid;
5035 sa->rtime.sec = ct.tv_sec;
5036 sa->rtime.nsec = ct.tv_nsec;
5037
5038 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
5039 BTRFS_UUID_SIZE);
5040 if (received_uuid_changed &&
5041 !btrfs_is_empty_uuid(root_item->received_uuid)) {
5042 ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid,
5043 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5044 root->root_key.objectid);
5045 if (ret && ret != -ENOENT) {
5046 btrfs_abort_transaction(trans, ret);
5047 btrfs_end_transaction(trans);
5048 goto out;
5049 }
5050 }
5051 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
5052 btrfs_set_root_stransid(root_item, sa->stransid);
5053 btrfs_set_root_rtransid(root_item, sa->rtransid);
5054 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
5055 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
5056 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
5057 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
5058
5059 ret = btrfs_update_root(trans, fs_info->tree_root,
5060 &root->root_key, &root->root_item);
5061 if (ret < 0) {
5062 btrfs_end_transaction(trans);
5063 goto out;
5064 }
5065 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
5066 ret = btrfs_uuid_tree_add(trans, sa->uuid,
5067 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5068 root->root_key.objectid);
5069 if (ret < 0 && ret != -EEXIST) {
5070 btrfs_abort_transaction(trans, ret);
5071 btrfs_end_transaction(trans);
5072 goto out;
5073 }
5074 }
5075 ret = btrfs_commit_transaction(trans);
5076out:
5077 up_write(&fs_info->subvol_sem);
5078 mnt_drop_write_file(file);
5079 return ret;
5080}
5081
5082#ifdef CONFIG_64BIT
5083static long btrfs_ioctl_set_received_subvol_32(struct file *file,
5084 void __user *arg)
5085{
5086 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
5087 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
5088 int ret = 0;
5089
5090 args32 = memdup_user(arg, sizeof(*args32));
5091 if (IS_ERR(args32))
5092 return PTR_ERR(args32);
5093
5094 args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
5095 if (!args64) {
5096 ret = -ENOMEM;
5097 goto out;
5098 }
5099
5100 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
5101 args64->stransid = args32->stransid;
5102 args64->rtransid = args32->rtransid;
5103 args64->stime.sec = args32->stime.sec;
5104 args64->stime.nsec = args32->stime.nsec;
5105 args64->rtime.sec = args32->rtime.sec;
5106 args64->rtime.nsec = args32->rtime.nsec;
5107 args64->flags = args32->flags;
5108
5109 ret = _btrfs_ioctl_set_received_subvol(file, args64);
5110 if (ret)
5111 goto out;
5112
5113 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
5114 args32->stransid = args64->stransid;
5115 args32->rtransid = args64->rtransid;
5116 args32->stime.sec = args64->stime.sec;
5117 args32->stime.nsec = args64->stime.nsec;
5118 args32->rtime.sec = args64->rtime.sec;
5119 args32->rtime.nsec = args64->rtime.nsec;
5120 args32->flags = args64->flags;
5121
5122 ret = copy_to_user(arg, args32, sizeof(*args32));
5123 if (ret)
5124 ret = -EFAULT;
5125
5126out:
5127 kfree(args32);
5128 kfree(args64);
5129 return ret;
5130}
5131#endif
5132
5133static long btrfs_ioctl_set_received_subvol(struct file *file,
5134 void __user *arg)
5135{
5136 struct btrfs_ioctl_received_subvol_args *sa = NULL;
5137 int ret = 0;
5138
5139 sa = memdup_user(arg, sizeof(*sa));
5140 if (IS_ERR(sa))
5141 return PTR_ERR(sa);
5142
5143 ret = _btrfs_ioctl_set_received_subvol(file, sa);
5144
5145 if (ret)
5146 goto out;
5147
5148 ret = copy_to_user(arg, sa, sizeof(*sa));
5149 if (ret)
5150 ret = -EFAULT;
5151
5152out:
5153 kfree(sa);
5154 return ret;
5155}
5156
5157static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
5158{
5159 struct inode *inode = file_inode(file);
5160 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5161 size_t len;
5162 int ret;
5163 char label[BTRFS_LABEL_SIZE];
5164
5165 spin_lock(&fs_info->super_lock);
5166 memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5167 spin_unlock(&fs_info->super_lock);
5168
5169 len = strnlen(label, BTRFS_LABEL_SIZE);
5170
5171 if (len == BTRFS_LABEL_SIZE) {
5172 btrfs_warn(fs_info,
5173 "label is too long, return the first %zu bytes",
5174 --len);
5175 }
5176
5177 ret = copy_to_user(arg, label, len);
5178
5179 return ret ? -EFAULT : 0;
5180}
5181
5182static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5183{
5184 struct inode *inode = file_inode(file);
5185 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5186 struct btrfs_root *root = BTRFS_I(inode)->root;
5187 struct btrfs_super_block *super_block = fs_info->super_copy;
5188 struct btrfs_trans_handle *trans;
5189 char label[BTRFS_LABEL_SIZE];
5190 int ret;
5191
5192 if (!capable(CAP_SYS_ADMIN))
5193 return -EPERM;
5194
5195 if (copy_from_user(label, arg, sizeof(label)))
5196 return -EFAULT;
5197
5198 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5199 btrfs_err(fs_info,
5200 "unable to set label with more than %d bytes",
5201 BTRFS_LABEL_SIZE - 1);
5202 return -EINVAL;
5203 }
5204
5205 ret = mnt_want_write_file(file);
5206 if (ret)
5207 return ret;
5208
5209 trans = btrfs_start_transaction(root, 0);
5210 if (IS_ERR(trans)) {
5211 ret = PTR_ERR(trans);
5212 goto out_unlock;
5213 }
5214
5215 spin_lock(&fs_info->super_lock);
5216 strcpy(super_block->label, label);
5217 spin_unlock(&fs_info->super_lock);
5218 ret = btrfs_commit_transaction(trans);
5219
5220out_unlock:
5221 mnt_drop_write_file(file);
5222 return ret;
5223}
5224
5225#define INIT_FEATURE_FLAGS(suffix) \
5226 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5227 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5228 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5229
5230int btrfs_ioctl_get_supported_features(void __user *arg)
5231{
5232 static const struct btrfs_ioctl_feature_flags features[3] = {
5233 INIT_FEATURE_FLAGS(SUPP),
5234 INIT_FEATURE_FLAGS(SAFE_SET),
5235 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5236 };
5237
5238 if (copy_to_user(arg, &features, sizeof(features)))
5239 return -EFAULT;
5240
5241 return 0;
5242}
5243
5244static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5245{
5246 struct inode *inode = file_inode(file);
5247 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5248 struct btrfs_super_block *super_block = fs_info->super_copy;
5249 struct btrfs_ioctl_feature_flags features;
5250
5251 features.compat_flags = btrfs_super_compat_flags(super_block);
5252 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5253 features.incompat_flags = btrfs_super_incompat_flags(super_block);
5254
5255 if (copy_to_user(arg, &features, sizeof(features)))
5256 return -EFAULT;
5257
5258 return 0;
5259}
5260
5261static int check_feature_bits(struct btrfs_fs_info *fs_info,
5262 enum btrfs_feature_set set,
5263 u64 change_mask, u64 flags, u64 supported_flags,
5264 u64 safe_set, u64 safe_clear)
5265{
5266 const char *type = btrfs_feature_set_name(set);
5267 char *names;
5268 u64 disallowed, unsupported;
5269 u64 set_mask = flags & change_mask;
5270 u64 clear_mask = ~flags & change_mask;
5271
5272 unsupported = set_mask & ~supported_flags;
5273 if (unsupported) {
5274 names = btrfs_printable_features(set, unsupported);
5275 if (names) {
5276 btrfs_warn(fs_info,
5277 "this kernel does not support the %s feature bit%s",
5278 names, strchr(names, ',') ? "s" : "");
5279 kfree(names);
5280 } else
5281 btrfs_warn(fs_info,
5282 "this kernel does not support %s bits 0x%llx",
5283 type, unsupported);
5284 return -EOPNOTSUPP;
5285 }
5286
5287 disallowed = set_mask & ~safe_set;
5288 if (disallowed) {
5289 names = btrfs_printable_features(set, disallowed);
5290 if (names) {
5291 btrfs_warn(fs_info,
5292 "can't set the %s feature bit%s while mounted",
5293 names, strchr(names, ',') ? "s" : "");
5294 kfree(names);
5295 } else
5296 btrfs_warn(fs_info,
5297 "can't set %s bits 0x%llx while mounted",
5298 type, disallowed);
5299 return -EPERM;
5300 }
5301
5302 disallowed = clear_mask & ~safe_clear;
5303 if (disallowed) {
5304 names = btrfs_printable_features(set, disallowed);
5305 if (names) {
5306 btrfs_warn(fs_info,
5307 "can't clear the %s feature bit%s while mounted",
5308 names, strchr(names, ',') ? "s" : "");
5309 kfree(names);
5310 } else
5311 btrfs_warn(fs_info,
5312 "can't clear %s bits 0x%llx while mounted",
5313 type, disallowed);
5314 return -EPERM;
5315 }
5316
5317 return 0;
5318}
5319
5320#define check_feature(fs_info, change_mask, flags, mask_base) \
5321check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags, \
5322 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
5323 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
5324 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5325
5326static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5327{
5328 struct inode *inode = file_inode(file);
5329 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5330 struct btrfs_root *root = BTRFS_I(inode)->root;
5331 struct btrfs_super_block *super_block = fs_info->super_copy;
5332 struct btrfs_ioctl_feature_flags flags[2];
5333 struct btrfs_trans_handle *trans;
5334 u64 newflags;
5335 int ret;
5336
5337 if (!capable(CAP_SYS_ADMIN))
5338 return -EPERM;
5339
5340 if (copy_from_user(flags, arg, sizeof(flags)))
5341 return -EFAULT;
5342
5343 /* Nothing to do */
5344 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5345 !flags[0].incompat_flags)
5346 return 0;
5347
5348 ret = check_feature(fs_info, flags[0].compat_flags,
5349 flags[1].compat_flags, COMPAT);
5350 if (ret)
5351 return ret;
5352
5353 ret = check_feature(fs_info, flags[0].compat_ro_flags,
5354 flags[1].compat_ro_flags, COMPAT_RO);
5355 if (ret)
5356 return ret;
5357
5358 ret = check_feature(fs_info, flags[0].incompat_flags,
5359 flags[1].incompat_flags, INCOMPAT);
5360 if (ret)
5361 return ret;
5362
5363 ret = mnt_want_write_file(file);
5364 if (ret)
5365 return ret;
5366
5367 trans = btrfs_start_transaction(root, 0);
5368 if (IS_ERR(trans)) {
5369 ret = PTR_ERR(trans);
5370 goto out_drop_write;
5371 }
5372
5373 spin_lock(&fs_info->super_lock);
5374 newflags = btrfs_super_compat_flags(super_block);
5375 newflags |= flags[0].compat_flags & flags[1].compat_flags;
5376 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5377 btrfs_set_super_compat_flags(super_block, newflags);
5378
5379 newflags = btrfs_super_compat_ro_flags(super_block);
5380 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5381 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5382 btrfs_set_super_compat_ro_flags(super_block, newflags);
5383
5384 newflags = btrfs_super_incompat_flags(super_block);
5385 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5386 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5387 btrfs_set_super_incompat_flags(super_block, newflags);
5388 spin_unlock(&fs_info->super_lock);
5389
5390 ret = btrfs_commit_transaction(trans);
5391out_drop_write:
5392 mnt_drop_write_file(file);
5393
5394 return ret;
5395}
5396
5397static int _btrfs_ioctl_send(struct file *file, void __user *argp, bool compat)
5398{
5399 struct btrfs_ioctl_send_args *arg;
5400 int ret;
5401
5402 if (compat) {
5403#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
5404 struct btrfs_ioctl_send_args_32 args32;
5405
5406 ret = copy_from_user(&args32, argp, sizeof(args32));
5407 if (ret)
5408 return -EFAULT;
5409 arg = kzalloc(sizeof(*arg), GFP_KERNEL);
5410 if (!arg)
5411 return -ENOMEM;
5412 arg->send_fd = args32.send_fd;
5413 arg->clone_sources_count = args32.clone_sources_count;
5414 arg->clone_sources = compat_ptr(args32.clone_sources);
5415 arg->parent_root = args32.parent_root;
5416 arg->flags = args32.flags;
5417 memcpy(arg->reserved, args32.reserved,
5418 sizeof(args32.reserved));
5419#else
5420 return -ENOTTY;
5421#endif
5422 } else {
5423 arg = memdup_user(argp, sizeof(*arg));
5424 if (IS_ERR(arg))
5425 return PTR_ERR(arg);
5426 }
5427 ret = btrfs_ioctl_send(file, arg);
5428 kfree(arg);
5429 return ret;
5430}
5431
5432long btrfs_ioctl(struct file *file, unsigned int
5433 cmd, unsigned long arg)
5434{
5435 struct inode *inode = file_inode(file);
5436 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5437 struct btrfs_root *root = BTRFS_I(inode)->root;
5438 void __user *argp = (void __user *)arg;
5439
5440 switch (cmd) {
5441 case FS_IOC_GETFLAGS:
5442 return btrfs_ioctl_getflags(file, argp);
5443 case FS_IOC_SETFLAGS:
5444 return btrfs_ioctl_setflags(file, argp);
5445 case FS_IOC_GETVERSION:
5446 return btrfs_ioctl_getversion(file, argp);
5447 case FS_IOC_GETFSLABEL:
5448 return btrfs_ioctl_get_fslabel(file, argp);
5449 case FS_IOC_SETFSLABEL:
5450 return btrfs_ioctl_set_fslabel(file, argp);
5451 case FITRIM:
5452 return btrfs_ioctl_fitrim(file, argp);
5453 case BTRFS_IOC_SNAP_CREATE:
5454 return btrfs_ioctl_snap_create(file, argp, 0);
5455 case BTRFS_IOC_SNAP_CREATE_V2:
5456 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5457 case BTRFS_IOC_SUBVOL_CREATE:
5458 return btrfs_ioctl_snap_create(file, argp, 1);
5459 case BTRFS_IOC_SUBVOL_CREATE_V2:
5460 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5461 case BTRFS_IOC_SNAP_DESTROY:
5462 return btrfs_ioctl_snap_destroy(file, argp);
5463 case BTRFS_IOC_SUBVOL_GETFLAGS:
5464 return btrfs_ioctl_subvol_getflags(file, argp);
5465 case BTRFS_IOC_SUBVOL_SETFLAGS:
5466 return btrfs_ioctl_subvol_setflags(file, argp);
5467 case BTRFS_IOC_DEFAULT_SUBVOL:
5468 return btrfs_ioctl_default_subvol(file, argp);
5469 case BTRFS_IOC_DEFRAG:
5470 return btrfs_ioctl_defrag(file, NULL);
5471 case BTRFS_IOC_DEFRAG_RANGE:
5472 return btrfs_ioctl_defrag(file, argp);
5473 case BTRFS_IOC_RESIZE:
5474 return btrfs_ioctl_resize(file, argp);
5475 case BTRFS_IOC_ADD_DEV:
5476 return btrfs_ioctl_add_dev(fs_info, argp);
5477 case BTRFS_IOC_RM_DEV:
5478 return btrfs_ioctl_rm_dev(file, argp);
5479 case BTRFS_IOC_RM_DEV_V2:
5480 return btrfs_ioctl_rm_dev_v2(file, argp);
5481 case BTRFS_IOC_FS_INFO:
5482 return btrfs_ioctl_fs_info(fs_info, argp);
5483 case BTRFS_IOC_DEV_INFO:
5484 return btrfs_ioctl_dev_info(fs_info, argp);
5485 case BTRFS_IOC_BALANCE:
5486 return btrfs_ioctl_balance(file, NULL);
5487 case BTRFS_IOC_TREE_SEARCH:
5488 return btrfs_ioctl_tree_search(file, argp);
5489 case BTRFS_IOC_TREE_SEARCH_V2:
5490 return btrfs_ioctl_tree_search_v2(file, argp);
5491 case BTRFS_IOC_INO_LOOKUP:
5492 return btrfs_ioctl_ino_lookup(file, argp);
5493 case BTRFS_IOC_INO_PATHS:
5494 return btrfs_ioctl_ino_to_path(root, argp);
5495 case BTRFS_IOC_LOGICAL_INO:
5496 return btrfs_ioctl_logical_to_ino(fs_info, argp, 1);
5497 case BTRFS_IOC_LOGICAL_INO_V2:
5498 return btrfs_ioctl_logical_to_ino(fs_info, argp, 2);
5499 case BTRFS_IOC_SPACE_INFO:
5500 return btrfs_ioctl_space_info(fs_info, argp);
5501 case BTRFS_IOC_SYNC: {
5502 int ret;
5503
5504 ret = btrfs_start_delalloc_roots(fs_info, -1);
5505 if (ret)
5506 return ret;
5507 ret = btrfs_sync_fs(inode->i_sb, 1);
5508 /*
5509 * The transaction thread may want to do more work,
5510 * namely it pokes the cleaner kthread that will start
5511 * processing uncleaned subvols.
5512 */
5513 wake_up_process(fs_info->transaction_kthread);
5514 return ret;
5515 }
5516 case BTRFS_IOC_START_SYNC:
5517 return btrfs_ioctl_start_sync(root, argp);
5518 case BTRFS_IOC_WAIT_SYNC:
5519 return btrfs_ioctl_wait_sync(fs_info, argp);
5520 case BTRFS_IOC_SCRUB:
5521 return btrfs_ioctl_scrub(file, argp);
5522 case BTRFS_IOC_SCRUB_CANCEL:
5523 return btrfs_ioctl_scrub_cancel(fs_info);
5524 case BTRFS_IOC_SCRUB_PROGRESS:
5525 return btrfs_ioctl_scrub_progress(fs_info, argp);
5526 case BTRFS_IOC_BALANCE_V2:
5527 return btrfs_ioctl_balance(file, argp);
5528 case BTRFS_IOC_BALANCE_CTL:
5529 return btrfs_ioctl_balance_ctl(fs_info, arg);
5530 case BTRFS_IOC_BALANCE_PROGRESS:
5531 return btrfs_ioctl_balance_progress(fs_info, argp);
5532 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5533 return btrfs_ioctl_set_received_subvol(file, argp);
5534#ifdef CONFIG_64BIT
5535 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5536 return btrfs_ioctl_set_received_subvol_32(file, argp);
5537#endif
5538 case BTRFS_IOC_SEND:
5539 return _btrfs_ioctl_send(file, argp, false);
5540#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
5541 case BTRFS_IOC_SEND_32:
5542 return _btrfs_ioctl_send(file, argp, true);
5543#endif
5544 case BTRFS_IOC_GET_DEV_STATS:
5545 return btrfs_ioctl_get_dev_stats(fs_info, argp);
5546 case BTRFS_IOC_QUOTA_CTL:
5547 return btrfs_ioctl_quota_ctl(file, argp);
5548 case BTRFS_IOC_QGROUP_ASSIGN:
5549 return btrfs_ioctl_qgroup_assign(file, argp);
5550 case BTRFS_IOC_QGROUP_CREATE:
5551 return btrfs_ioctl_qgroup_create(file, argp);
5552 case BTRFS_IOC_QGROUP_LIMIT:
5553 return btrfs_ioctl_qgroup_limit(file, argp);
5554 case BTRFS_IOC_QUOTA_RESCAN:
5555 return btrfs_ioctl_quota_rescan(file, argp);
5556 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5557 return btrfs_ioctl_quota_rescan_status(file, argp);
5558 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5559 return btrfs_ioctl_quota_rescan_wait(file, argp);
5560 case BTRFS_IOC_DEV_REPLACE:
5561 return btrfs_ioctl_dev_replace(fs_info, argp);
5562 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5563 return btrfs_ioctl_get_supported_features(argp);
5564 case BTRFS_IOC_GET_FEATURES:
5565 return btrfs_ioctl_get_features(file, argp);
5566 case BTRFS_IOC_SET_FEATURES:
5567 return btrfs_ioctl_set_features(file, argp);
5568 case FS_IOC_FSGETXATTR:
5569 return btrfs_ioctl_fsgetxattr(file, argp);
5570 case FS_IOC_FSSETXATTR:
5571 return btrfs_ioctl_fssetxattr(file, argp);
5572 case BTRFS_IOC_GET_SUBVOL_INFO:
5573 return btrfs_ioctl_get_subvol_info(file, argp);
5574 case BTRFS_IOC_GET_SUBVOL_ROOTREF:
5575 return btrfs_ioctl_get_subvol_rootref(file, argp);
5576 case BTRFS_IOC_INO_LOOKUP_USER:
5577 return btrfs_ioctl_ino_lookup_user(file, argp);
5578 }
5579
5580 return -ENOTTY;
5581}
5582
5583#ifdef CONFIG_COMPAT
5584long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
5585{
5586 /*
5587 * These all access 32-bit values anyway so no further
5588 * handling is necessary.
5589 */
5590 switch (cmd) {
5591 case FS_IOC32_GETFLAGS:
5592 cmd = FS_IOC_GETFLAGS;
5593 break;
5594 case FS_IOC32_SETFLAGS:
5595 cmd = FS_IOC_SETFLAGS;
5596 break;
5597 case FS_IOC32_GETVERSION:
5598 cmd = FS_IOC_GETVERSION;
5599 break;
5600 }
5601
5602 return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
5603}
5604#endif