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Btrfs: add support for device replace ioctls
[deliverable/linux.git] / fs / btrfs / ioctl.c
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19 #include <linux/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.h>
23 #include <linux/fs.h>
24 #include <linux/fsnotify.h>
25 #include <linux/pagemap.h>
26 #include <linux/highmem.h>
27 #include <linux/time.h>
28 #include <linux/init.h>
29 #include <linux/string.h>
30 #include <linux/backing-dev.h>
31 #include <linux/mount.h>
32 #include <linux/mpage.h>
33 #include <linux/namei.h>
34 #include <linux/swap.h>
35 #include <linux/writeback.h>
36 #include <linux/statfs.h>
37 #include <linux/compat.h>
38 #include <linux/bit_spinlock.h>
39 #include <linux/security.h>
40 #include <linux/xattr.h>
41 #include <linux/vmalloc.h>
42 #include <linux/slab.h>
43 #include <linux/blkdev.h>
44 #include <linux/uuid.h>
45 #include "compat.h"
46 #include "ctree.h"
47 #include "disk-io.h"
48 #include "transaction.h"
49 #include "btrfs_inode.h"
50 #include "ioctl.h"
51 #include "print-tree.h"
52 #include "volumes.h"
53 #include "locking.h"
54 #include "inode-map.h"
55 #include "backref.h"
56 #include "rcu-string.h"
57 #include "send.h"
58 #include "dev-replace.h"
59
60 /* Mask out flags that are inappropriate for the given type of inode. */
61 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
62 {
63 if (S_ISDIR(mode))
64 return flags;
65 else if (S_ISREG(mode))
66 return flags & ~FS_DIRSYNC_FL;
67 else
68 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
69 }
70
71 /*
72 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
73 */
74 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
75 {
76 unsigned int iflags = 0;
77
78 if (flags & BTRFS_INODE_SYNC)
79 iflags |= FS_SYNC_FL;
80 if (flags & BTRFS_INODE_IMMUTABLE)
81 iflags |= FS_IMMUTABLE_FL;
82 if (flags & BTRFS_INODE_APPEND)
83 iflags |= FS_APPEND_FL;
84 if (flags & BTRFS_INODE_NODUMP)
85 iflags |= FS_NODUMP_FL;
86 if (flags & BTRFS_INODE_NOATIME)
87 iflags |= FS_NOATIME_FL;
88 if (flags & BTRFS_INODE_DIRSYNC)
89 iflags |= FS_DIRSYNC_FL;
90 if (flags & BTRFS_INODE_NODATACOW)
91 iflags |= FS_NOCOW_FL;
92
93 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
94 iflags |= FS_COMPR_FL;
95 else if (flags & BTRFS_INODE_NOCOMPRESS)
96 iflags |= FS_NOCOMP_FL;
97
98 return iflags;
99 }
100
101 /*
102 * Update inode->i_flags based on the btrfs internal flags.
103 */
104 void btrfs_update_iflags(struct inode *inode)
105 {
106 struct btrfs_inode *ip = BTRFS_I(inode);
107
108 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
109
110 if (ip->flags & BTRFS_INODE_SYNC)
111 inode->i_flags |= S_SYNC;
112 if (ip->flags & BTRFS_INODE_IMMUTABLE)
113 inode->i_flags |= S_IMMUTABLE;
114 if (ip->flags & BTRFS_INODE_APPEND)
115 inode->i_flags |= S_APPEND;
116 if (ip->flags & BTRFS_INODE_NOATIME)
117 inode->i_flags |= S_NOATIME;
118 if (ip->flags & BTRFS_INODE_DIRSYNC)
119 inode->i_flags |= S_DIRSYNC;
120 }
121
122 /*
123 * Inherit flags from the parent inode.
124 *
125 * Currently only the compression flags and the cow flags are inherited.
126 */
127 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
128 {
129 unsigned int flags;
130
131 if (!dir)
132 return;
133
134 flags = BTRFS_I(dir)->flags;
135
136 if (flags & BTRFS_INODE_NOCOMPRESS) {
137 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
138 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
139 } else if (flags & BTRFS_INODE_COMPRESS) {
140 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
141 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
142 }
143
144 if (flags & BTRFS_INODE_NODATACOW)
145 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
146
147 btrfs_update_iflags(inode);
148 }
149
150 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
151 {
152 struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
153 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
154
155 if (copy_to_user(arg, &flags, sizeof(flags)))
156 return -EFAULT;
157 return 0;
158 }
159
160 static int check_flags(unsigned int flags)
161 {
162 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
163 FS_NOATIME_FL | FS_NODUMP_FL | \
164 FS_SYNC_FL | FS_DIRSYNC_FL | \
165 FS_NOCOMP_FL | FS_COMPR_FL |
166 FS_NOCOW_FL))
167 return -EOPNOTSUPP;
168
169 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
170 return -EINVAL;
171
172 return 0;
173 }
174
175 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
176 {
177 struct inode *inode = file->f_path.dentry->d_inode;
178 struct btrfs_inode *ip = BTRFS_I(inode);
179 struct btrfs_root *root = ip->root;
180 struct btrfs_trans_handle *trans;
181 unsigned int flags, oldflags;
182 int ret;
183 u64 ip_oldflags;
184 unsigned int i_oldflags;
185 umode_t mode;
186
187 if (btrfs_root_readonly(root))
188 return -EROFS;
189
190 if (copy_from_user(&flags, arg, sizeof(flags)))
191 return -EFAULT;
192
193 ret = check_flags(flags);
194 if (ret)
195 return ret;
196
197 if (!inode_owner_or_capable(inode))
198 return -EACCES;
199
200 ret = mnt_want_write_file(file);
201 if (ret)
202 return ret;
203
204 mutex_lock(&inode->i_mutex);
205
206 ip_oldflags = ip->flags;
207 i_oldflags = inode->i_flags;
208 mode = inode->i_mode;
209
210 flags = btrfs_mask_flags(inode->i_mode, flags);
211 oldflags = btrfs_flags_to_ioctl(ip->flags);
212 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
213 if (!capable(CAP_LINUX_IMMUTABLE)) {
214 ret = -EPERM;
215 goto out_unlock;
216 }
217 }
218
219 if (flags & FS_SYNC_FL)
220 ip->flags |= BTRFS_INODE_SYNC;
221 else
222 ip->flags &= ~BTRFS_INODE_SYNC;
223 if (flags & FS_IMMUTABLE_FL)
224 ip->flags |= BTRFS_INODE_IMMUTABLE;
225 else
226 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
227 if (flags & FS_APPEND_FL)
228 ip->flags |= BTRFS_INODE_APPEND;
229 else
230 ip->flags &= ~BTRFS_INODE_APPEND;
231 if (flags & FS_NODUMP_FL)
232 ip->flags |= BTRFS_INODE_NODUMP;
233 else
234 ip->flags &= ~BTRFS_INODE_NODUMP;
235 if (flags & FS_NOATIME_FL)
236 ip->flags |= BTRFS_INODE_NOATIME;
237 else
238 ip->flags &= ~BTRFS_INODE_NOATIME;
239 if (flags & FS_DIRSYNC_FL)
240 ip->flags |= BTRFS_INODE_DIRSYNC;
241 else
242 ip->flags &= ~BTRFS_INODE_DIRSYNC;
243 if (flags & FS_NOCOW_FL) {
244 if (S_ISREG(mode)) {
245 /*
246 * It's safe to turn csums off here, no extents exist.
247 * Otherwise we want the flag to reflect the real COW
248 * status of the file and will not set it.
249 */
250 if (inode->i_size == 0)
251 ip->flags |= BTRFS_INODE_NODATACOW
252 | BTRFS_INODE_NODATASUM;
253 } else {
254 ip->flags |= BTRFS_INODE_NODATACOW;
255 }
256 } else {
257 /*
258 * Revert back under same assuptions as above
259 */
260 if (S_ISREG(mode)) {
261 if (inode->i_size == 0)
262 ip->flags &= ~(BTRFS_INODE_NODATACOW
263 | BTRFS_INODE_NODATASUM);
264 } else {
265 ip->flags &= ~BTRFS_INODE_NODATACOW;
266 }
267 }
268
269 /*
270 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
271 * flag may be changed automatically if compression code won't make
272 * things smaller.
273 */
274 if (flags & FS_NOCOMP_FL) {
275 ip->flags &= ~BTRFS_INODE_COMPRESS;
276 ip->flags |= BTRFS_INODE_NOCOMPRESS;
277 } else if (flags & FS_COMPR_FL) {
278 ip->flags |= BTRFS_INODE_COMPRESS;
279 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
280 } else {
281 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
282 }
283
284 trans = btrfs_start_transaction(root, 1);
285 if (IS_ERR(trans)) {
286 ret = PTR_ERR(trans);
287 goto out_drop;
288 }
289
290 btrfs_update_iflags(inode);
291 inode_inc_iversion(inode);
292 inode->i_ctime = CURRENT_TIME;
293 ret = btrfs_update_inode(trans, root, inode);
294
295 btrfs_end_transaction(trans, root);
296 out_drop:
297 if (ret) {
298 ip->flags = ip_oldflags;
299 inode->i_flags = i_oldflags;
300 }
301
302 out_unlock:
303 mutex_unlock(&inode->i_mutex);
304 mnt_drop_write_file(file);
305 return ret;
306 }
307
308 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
309 {
310 struct inode *inode = file->f_path.dentry->d_inode;
311
312 return put_user(inode->i_generation, arg);
313 }
314
315 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
316 {
317 struct btrfs_fs_info *fs_info = btrfs_sb(fdentry(file)->d_sb);
318 struct btrfs_device *device;
319 struct request_queue *q;
320 struct fstrim_range range;
321 u64 minlen = ULLONG_MAX;
322 u64 num_devices = 0;
323 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
324 int ret;
325
326 if (!capable(CAP_SYS_ADMIN))
327 return -EPERM;
328
329 rcu_read_lock();
330 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
331 dev_list) {
332 if (!device->bdev)
333 continue;
334 q = bdev_get_queue(device->bdev);
335 if (blk_queue_discard(q)) {
336 num_devices++;
337 minlen = min((u64)q->limits.discard_granularity,
338 minlen);
339 }
340 }
341 rcu_read_unlock();
342
343 if (!num_devices)
344 return -EOPNOTSUPP;
345 if (copy_from_user(&range, arg, sizeof(range)))
346 return -EFAULT;
347 if (range.start > total_bytes ||
348 range.len < fs_info->sb->s_blocksize)
349 return -EINVAL;
350
351 range.len = min(range.len, total_bytes - range.start);
352 range.minlen = max(range.minlen, minlen);
353 ret = btrfs_trim_fs(fs_info->tree_root, &range);
354 if (ret < 0)
355 return ret;
356
357 if (copy_to_user(arg, &range, sizeof(range)))
358 return -EFAULT;
359
360 return 0;
361 }
362
363 static noinline int create_subvol(struct btrfs_root *root,
364 struct dentry *dentry,
365 char *name, int namelen,
366 u64 *async_transid,
367 struct btrfs_qgroup_inherit **inherit)
368 {
369 struct btrfs_trans_handle *trans;
370 struct btrfs_key key;
371 struct btrfs_root_item root_item;
372 struct btrfs_inode_item *inode_item;
373 struct extent_buffer *leaf;
374 struct btrfs_root *new_root;
375 struct dentry *parent = dentry->d_parent;
376 struct inode *dir;
377 struct timespec cur_time = CURRENT_TIME;
378 int ret;
379 int err;
380 u64 objectid;
381 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
382 u64 index = 0;
383 uuid_le new_uuid;
384
385 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
386 if (ret)
387 return ret;
388
389 dir = parent->d_inode;
390
391 /*
392 * 1 - inode item
393 * 2 - refs
394 * 1 - root item
395 * 2 - dir items
396 */
397 trans = btrfs_start_transaction(root, 6);
398 if (IS_ERR(trans))
399 return PTR_ERR(trans);
400
401 ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid,
402 inherit ? *inherit : NULL);
403 if (ret)
404 goto fail;
405
406 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
407 0, objectid, NULL, 0, 0, 0);
408 if (IS_ERR(leaf)) {
409 ret = PTR_ERR(leaf);
410 goto fail;
411 }
412
413 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
414 btrfs_set_header_bytenr(leaf, leaf->start);
415 btrfs_set_header_generation(leaf, trans->transid);
416 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
417 btrfs_set_header_owner(leaf, objectid);
418
419 write_extent_buffer(leaf, root->fs_info->fsid,
420 (unsigned long)btrfs_header_fsid(leaf),
421 BTRFS_FSID_SIZE);
422 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
423 (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
424 BTRFS_UUID_SIZE);
425 btrfs_mark_buffer_dirty(leaf);
426
427 memset(&root_item, 0, sizeof(root_item));
428
429 inode_item = &root_item.inode;
430 inode_item->generation = cpu_to_le64(1);
431 inode_item->size = cpu_to_le64(3);
432 inode_item->nlink = cpu_to_le32(1);
433 inode_item->nbytes = cpu_to_le64(root->leafsize);
434 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
435
436 root_item.flags = 0;
437 root_item.byte_limit = 0;
438 inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
439
440 btrfs_set_root_bytenr(&root_item, leaf->start);
441 btrfs_set_root_generation(&root_item, trans->transid);
442 btrfs_set_root_level(&root_item, 0);
443 btrfs_set_root_refs(&root_item, 1);
444 btrfs_set_root_used(&root_item, leaf->len);
445 btrfs_set_root_last_snapshot(&root_item, 0);
446
447 btrfs_set_root_generation_v2(&root_item,
448 btrfs_root_generation(&root_item));
449 uuid_le_gen(&new_uuid);
450 memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
451 root_item.otime.sec = cpu_to_le64(cur_time.tv_sec);
452 root_item.otime.nsec = cpu_to_le32(cur_time.tv_nsec);
453 root_item.ctime = root_item.otime;
454 btrfs_set_root_ctransid(&root_item, trans->transid);
455 btrfs_set_root_otransid(&root_item, trans->transid);
456
457 btrfs_tree_unlock(leaf);
458 free_extent_buffer(leaf);
459 leaf = NULL;
460
461 btrfs_set_root_dirid(&root_item, new_dirid);
462
463 key.objectid = objectid;
464 key.offset = 0;
465 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
466 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
467 &root_item);
468 if (ret)
469 goto fail;
470
471 key.offset = (u64)-1;
472 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
473 if (IS_ERR(new_root)) {
474 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
475 ret = PTR_ERR(new_root);
476 goto fail;
477 }
478
479 btrfs_record_root_in_trans(trans, new_root);
480
481 ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
482 if (ret) {
483 /* We potentially lose an unused inode item here */
484 btrfs_abort_transaction(trans, root, ret);
485 goto fail;
486 }
487
488 /*
489 * insert the directory item
490 */
491 ret = btrfs_set_inode_index(dir, &index);
492 if (ret) {
493 btrfs_abort_transaction(trans, root, ret);
494 goto fail;
495 }
496
497 ret = btrfs_insert_dir_item(trans, root,
498 name, namelen, dir, &key,
499 BTRFS_FT_DIR, index);
500 if (ret) {
501 btrfs_abort_transaction(trans, root, ret);
502 goto fail;
503 }
504
505 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
506 ret = btrfs_update_inode(trans, root, dir);
507 BUG_ON(ret);
508
509 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
510 objectid, root->root_key.objectid,
511 btrfs_ino(dir), index, name, namelen);
512
513 BUG_ON(ret);
514
515 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
516 fail:
517 if (async_transid) {
518 *async_transid = trans->transid;
519 err = btrfs_commit_transaction_async(trans, root, 1);
520 } else {
521 err = btrfs_commit_transaction(trans, root);
522 }
523 if (err && !ret)
524 ret = err;
525 return ret;
526 }
527
528 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
529 char *name, int namelen, u64 *async_transid,
530 bool readonly, struct btrfs_qgroup_inherit **inherit)
531 {
532 struct inode *inode;
533 struct btrfs_pending_snapshot *pending_snapshot;
534 struct btrfs_trans_handle *trans;
535 int ret;
536
537 if (!root->ref_cows)
538 return -EINVAL;
539
540 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
541 if (!pending_snapshot)
542 return -ENOMEM;
543
544 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
545 BTRFS_BLOCK_RSV_TEMP);
546 pending_snapshot->dentry = dentry;
547 pending_snapshot->root = root;
548 pending_snapshot->readonly = readonly;
549 if (inherit) {
550 pending_snapshot->inherit = *inherit;
551 *inherit = NULL; /* take responsibility to free it */
552 }
553
554 trans = btrfs_start_transaction(root->fs_info->extent_root, 6);
555 if (IS_ERR(trans)) {
556 ret = PTR_ERR(trans);
557 goto fail;
558 }
559
560 ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
561 BUG_ON(ret);
562
563 spin_lock(&root->fs_info->trans_lock);
564 list_add(&pending_snapshot->list,
565 &trans->transaction->pending_snapshots);
566 spin_unlock(&root->fs_info->trans_lock);
567 if (async_transid) {
568 *async_transid = trans->transid;
569 ret = btrfs_commit_transaction_async(trans,
570 root->fs_info->extent_root, 1);
571 } else {
572 ret = btrfs_commit_transaction(trans,
573 root->fs_info->extent_root);
574 }
575 if (ret) {
576 /* cleanup_transaction has freed this for us */
577 if (trans->aborted)
578 pending_snapshot = NULL;
579 goto fail;
580 }
581
582 ret = pending_snapshot->error;
583 if (ret)
584 goto fail;
585
586 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
587 if (ret)
588 goto fail;
589
590 inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
591 if (IS_ERR(inode)) {
592 ret = PTR_ERR(inode);
593 goto fail;
594 }
595 BUG_ON(!inode);
596 d_instantiate(dentry, inode);
597 ret = 0;
598 fail:
599 kfree(pending_snapshot);
600 return ret;
601 }
602
603 /* copy of check_sticky in fs/namei.c()
604 * It's inline, so penalty for filesystems that don't use sticky bit is
605 * minimal.
606 */
607 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
608 {
609 kuid_t fsuid = current_fsuid();
610
611 if (!(dir->i_mode & S_ISVTX))
612 return 0;
613 if (uid_eq(inode->i_uid, fsuid))
614 return 0;
615 if (uid_eq(dir->i_uid, fsuid))
616 return 0;
617 return !capable(CAP_FOWNER);
618 }
619
620 /* copy of may_delete in fs/namei.c()
621 * Check whether we can remove a link victim from directory dir, check
622 * whether the type of victim is right.
623 * 1. We can't do it if dir is read-only (done in permission())
624 * 2. We should have write and exec permissions on dir
625 * 3. We can't remove anything from append-only dir
626 * 4. We can't do anything with immutable dir (done in permission())
627 * 5. If the sticky bit on dir is set we should either
628 * a. be owner of dir, or
629 * b. be owner of victim, or
630 * c. have CAP_FOWNER capability
631 * 6. If the victim is append-only or immutable we can't do antyhing with
632 * links pointing to it.
633 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
634 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
635 * 9. We can't remove a root or mountpoint.
636 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
637 * nfs_async_unlink().
638 */
639
640 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
641 {
642 int error;
643
644 if (!victim->d_inode)
645 return -ENOENT;
646
647 BUG_ON(victim->d_parent->d_inode != dir);
648 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
649
650 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
651 if (error)
652 return error;
653 if (IS_APPEND(dir))
654 return -EPERM;
655 if (btrfs_check_sticky(dir, victim->d_inode)||
656 IS_APPEND(victim->d_inode)||
657 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
658 return -EPERM;
659 if (isdir) {
660 if (!S_ISDIR(victim->d_inode->i_mode))
661 return -ENOTDIR;
662 if (IS_ROOT(victim))
663 return -EBUSY;
664 } else if (S_ISDIR(victim->d_inode->i_mode))
665 return -EISDIR;
666 if (IS_DEADDIR(dir))
667 return -ENOENT;
668 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
669 return -EBUSY;
670 return 0;
671 }
672
673 /* copy of may_create in fs/namei.c() */
674 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
675 {
676 if (child->d_inode)
677 return -EEXIST;
678 if (IS_DEADDIR(dir))
679 return -ENOENT;
680 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
681 }
682
683 /*
684 * Create a new subvolume below @parent. This is largely modeled after
685 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
686 * inside this filesystem so it's quite a bit simpler.
687 */
688 static noinline int btrfs_mksubvol(struct path *parent,
689 char *name, int namelen,
690 struct btrfs_root *snap_src,
691 u64 *async_transid, bool readonly,
692 struct btrfs_qgroup_inherit **inherit)
693 {
694 struct inode *dir = parent->dentry->d_inode;
695 struct dentry *dentry;
696 int error;
697
698 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
699
700 dentry = lookup_one_len(name, parent->dentry, namelen);
701 error = PTR_ERR(dentry);
702 if (IS_ERR(dentry))
703 goto out_unlock;
704
705 error = -EEXIST;
706 if (dentry->d_inode)
707 goto out_dput;
708
709 error = btrfs_may_create(dir, dentry);
710 if (error)
711 goto out_dput;
712
713 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
714
715 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
716 goto out_up_read;
717
718 if (snap_src) {
719 error = create_snapshot(snap_src, dentry, name, namelen,
720 async_transid, readonly, inherit);
721 } else {
722 error = create_subvol(BTRFS_I(dir)->root, dentry,
723 name, namelen, async_transid, inherit);
724 }
725 if (!error)
726 fsnotify_mkdir(dir, dentry);
727 out_up_read:
728 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
729 out_dput:
730 dput(dentry);
731 out_unlock:
732 mutex_unlock(&dir->i_mutex);
733 return error;
734 }
735
736 /*
737 * When we're defragging a range, we don't want to kick it off again
738 * if it is really just waiting for delalloc to send it down.
739 * If we find a nice big extent or delalloc range for the bytes in the
740 * file you want to defrag, we return 0 to let you know to skip this
741 * part of the file
742 */
743 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
744 {
745 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
746 struct extent_map *em = NULL;
747 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
748 u64 end;
749
750 read_lock(&em_tree->lock);
751 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
752 read_unlock(&em_tree->lock);
753
754 if (em) {
755 end = extent_map_end(em);
756 free_extent_map(em);
757 if (end - offset > thresh)
758 return 0;
759 }
760 /* if we already have a nice delalloc here, just stop */
761 thresh /= 2;
762 end = count_range_bits(io_tree, &offset, offset + thresh,
763 thresh, EXTENT_DELALLOC, 1);
764 if (end >= thresh)
765 return 0;
766 return 1;
767 }
768
769 /*
770 * helper function to walk through a file and find extents
771 * newer than a specific transid, and smaller than thresh.
772 *
773 * This is used by the defragging code to find new and small
774 * extents
775 */
776 static int find_new_extents(struct btrfs_root *root,
777 struct inode *inode, u64 newer_than,
778 u64 *off, int thresh)
779 {
780 struct btrfs_path *path;
781 struct btrfs_key min_key;
782 struct btrfs_key max_key;
783 struct extent_buffer *leaf;
784 struct btrfs_file_extent_item *extent;
785 int type;
786 int ret;
787 u64 ino = btrfs_ino(inode);
788
789 path = btrfs_alloc_path();
790 if (!path)
791 return -ENOMEM;
792
793 min_key.objectid = ino;
794 min_key.type = BTRFS_EXTENT_DATA_KEY;
795 min_key.offset = *off;
796
797 max_key.objectid = ino;
798 max_key.type = (u8)-1;
799 max_key.offset = (u64)-1;
800
801 path->keep_locks = 1;
802
803 while(1) {
804 ret = btrfs_search_forward(root, &min_key, &max_key,
805 path, 0, newer_than);
806 if (ret != 0)
807 goto none;
808 if (min_key.objectid != ino)
809 goto none;
810 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
811 goto none;
812
813 leaf = path->nodes[0];
814 extent = btrfs_item_ptr(leaf, path->slots[0],
815 struct btrfs_file_extent_item);
816
817 type = btrfs_file_extent_type(leaf, extent);
818 if (type == BTRFS_FILE_EXTENT_REG &&
819 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
820 check_defrag_in_cache(inode, min_key.offset, thresh)) {
821 *off = min_key.offset;
822 btrfs_free_path(path);
823 return 0;
824 }
825
826 if (min_key.offset == (u64)-1)
827 goto none;
828
829 min_key.offset++;
830 btrfs_release_path(path);
831 }
832 none:
833 btrfs_free_path(path);
834 return -ENOENT;
835 }
836
837 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
838 {
839 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
840 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
841 struct extent_map *em;
842 u64 len = PAGE_CACHE_SIZE;
843
844 /*
845 * hopefully we have this extent in the tree already, try without
846 * the full extent lock
847 */
848 read_lock(&em_tree->lock);
849 em = lookup_extent_mapping(em_tree, start, len);
850 read_unlock(&em_tree->lock);
851
852 if (!em) {
853 /* get the big lock and read metadata off disk */
854 lock_extent(io_tree, start, start + len - 1);
855 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
856 unlock_extent(io_tree, start, start + len - 1);
857
858 if (IS_ERR(em))
859 return NULL;
860 }
861
862 return em;
863 }
864
865 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
866 {
867 struct extent_map *next;
868 bool ret = true;
869
870 /* this is the last extent */
871 if (em->start + em->len >= i_size_read(inode))
872 return false;
873
874 next = defrag_lookup_extent(inode, em->start + em->len);
875 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
876 ret = false;
877
878 free_extent_map(next);
879 return ret;
880 }
881
882 static int should_defrag_range(struct inode *inode, u64 start, int thresh,
883 u64 *last_len, u64 *skip, u64 *defrag_end,
884 int compress)
885 {
886 struct extent_map *em;
887 int ret = 1;
888 bool next_mergeable = true;
889
890 /*
891 * make sure that once we start defragging an extent, we keep on
892 * defragging it
893 */
894 if (start < *defrag_end)
895 return 1;
896
897 *skip = 0;
898
899 em = defrag_lookup_extent(inode, start);
900 if (!em)
901 return 0;
902
903 /* this will cover holes, and inline extents */
904 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
905 ret = 0;
906 goto out;
907 }
908
909 next_mergeable = defrag_check_next_extent(inode, em);
910
911 /*
912 * we hit a real extent, if it is big or the next extent is not a
913 * real extent, don't bother defragging it
914 */
915 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
916 (em->len >= thresh || !next_mergeable))
917 ret = 0;
918 out:
919 /*
920 * last_len ends up being a counter of how many bytes we've defragged.
921 * every time we choose not to defrag an extent, we reset *last_len
922 * so that the next tiny extent will force a defrag.
923 *
924 * The end result of this is that tiny extents before a single big
925 * extent will force at least part of that big extent to be defragged.
926 */
927 if (ret) {
928 *defrag_end = extent_map_end(em);
929 } else {
930 *last_len = 0;
931 *skip = extent_map_end(em);
932 *defrag_end = 0;
933 }
934
935 free_extent_map(em);
936 return ret;
937 }
938
939 /*
940 * it doesn't do much good to defrag one or two pages
941 * at a time. This pulls in a nice chunk of pages
942 * to COW and defrag.
943 *
944 * It also makes sure the delalloc code has enough
945 * dirty data to avoid making new small extents as part
946 * of the defrag
947 *
948 * It's a good idea to start RA on this range
949 * before calling this.
950 */
951 static int cluster_pages_for_defrag(struct inode *inode,
952 struct page **pages,
953 unsigned long start_index,
954 int num_pages)
955 {
956 unsigned long file_end;
957 u64 isize = i_size_read(inode);
958 u64 page_start;
959 u64 page_end;
960 u64 page_cnt;
961 int ret;
962 int i;
963 int i_done;
964 struct btrfs_ordered_extent *ordered;
965 struct extent_state *cached_state = NULL;
966 struct extent_io_tree *tree;
967 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
968
969 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
970 if (!isize || start_index > file_end)
971 return 0;
972
973 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
974
975 ret = btrfs_delalloc_reserve_space(inode,
976 page_cnt << PAGE_CACHE_SHIFT);
977 if (ret)
978 return ret;
979 i_done = 0;
980 tree = &BTRFS_I(inode)->io_tree;
981
982 /* step one, lock all the pages */
983 for (i = 0; i < page_cnt; i++) {
984 struct page *page;
985 again:
986 page = find_or_create_page(inode->i_mapping,
987 start_index + i, mask);
988 if (!page)
989 break;
990
991 page_start = page_offset(page);
992 page_end = page_start + PAGE_CACHE_SIZE - 1;
993 while (1) {
994 lock_extent(tree, page_start, page_end);
995 ordered = btrfs_lookup_ordered_extent(inode,
996 page_start);
997 unlock_extent(tree, page_start, page_end);
998 if (!ordered)
999 break;
1000
1001 unlock_page(page);
1002 btrfs_start_ordered_extent(inode, ordered, 1);
1003 btrfs_put_ordered_extent(ordered);
1004 lock_page(page);
1005 /*
1006 * we unlocked the page above, so we need check if
1007 * it was released or not.
1008 */
1009 if (page->mapping != inode->i_mapping) {
1010 unlock_page(page);
1011 page_cache_release(page);
1012 goto again;
1013 }
1014 }
1015
1016 if (!PageUptodate(page)) {
1017 btrfs_readpage(NULL, page);
1018 lock_page(page);
1019 if (!PageUptodate(page)) {
1020 unlock_page(page);
1021 page_cache_release(page);
1022 ret = -EIO;
1023 break;
1024 }
1025 }
1026
1027 if (page->mapping != inode->i_mapping) {
1028 unlock_page(page);
1029 page_cache_release(page);
1030 goto again;
1031 }
1032
1033 pages[i] = page;
1034 i_done++;
1035 }
1036 if (!i_done || ret)
1037 goto out;
1038
1039 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1040 goto out;
1041
1042 /*
1043 * so now we have a nice long stream of locked
1044 * and up to date pages, lets wait on them
1045 */
1046 for (i = 0; i < i_done; i++)
1047 wait_on_page_writeback(pages[i]);
1048
1049 page_start = page_offset(pages[0]);
1050 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1051
1052 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1053 page_start, page_end - 1, 0, &cached_state);
1054 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1055 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1056 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1057 &cached_state, GFP_NOFS);
1058
1059 if (i_done != page_cnt) {
1060 spin_lock(&BTRFS_I(inode)->lock);
1061 BTRFS_I(inode)->outstanding_extents++;
1062 spin_unlock(&BTRFS_I(inode)->lock);
1063 btrfs_delalloc_release_space(inode,
1064 (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1065 }
1066
1067
1068 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1069 &cached_state, GFP_NOFS);
1070
1071 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1072 page_start, page_end - 1, &cached_state,
1073 GFP_NOFS);
1074
1075 for (i = 0; i < i_done; i++) {
1076 clear_page_dirty_for_io(pages[i]);
1077 ClearPageChecked(pages[i]);
1078 set_page_extent_mapped(pages[i]);
1079 set_page_dirty(pages[i]);
1080 unlock_page(pages[i]);
1081 page_cache_release(pages[i]);
1082 }
1083 return i_done;
1084 out:
1085 for (i = 0; i < i_done; i++) {
1086 unlock_page(pages[i]);
1087 page_cache_release(pages[i]);
1088 }
1089 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1090 return ret;
1091
1092 }
1093
1094 int btrfs_defrag_file(struct inode *inode, struct file *file,
1095 struct btrfs_ioctl_defrag_range_args *range,
1096 u64 newer_than, unsigned long max_to_defrag)
1097 {
1098 struct btrfs_root *root = BTRFS_I(inode)->root;
1099 struct file_ra_state *ra = NULL;
1100 unsigned long last_index;
1101 u64 isize = i_size_read(inode);
1102 u64 last_len = 0;
1103 u64 skip = 0;
1104 u64 defrag_end = 0;
1105 u64 newer_off = range->start;
1106 unsigned long i;
1107 unsigned long ra_index = 0;
1108 int ret;
1109 int defrag_count = 0;
1110 int compress_type = BTRFS_COMPRESS_ZLIB;
1111 int extent_thresh = range->extent_thresh;
1112 int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1113 int cluster = max_cluster;
1114 u64 new_align = ~((u64)128 * 1024 - 1);
1115 struct page **pages = NULL;
1116
1117 if (extent_thresh == 0)
1118 extent_thresh = 256 * 1024;
1119
1120 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1121 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1122 return -EINVAL;
1123 if (range->compress_type)
1124 compress_type = range->compress_type;
1125 }
1126
1127 if (isize == 0)
1128 return 0;
1129
1130 /*
1131 * if we were not given a file, allocate a readahead
1132 * context
1133 */
1134 if (!file) {
1135 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1136 if (!ra)
1137 return -ENOMEM;
1138 file_ra_state_init(ra, inode->i_mapping);
1139 } else {
1140 ra = &file->f_ra;
1141 }
1142
1143 pages = kmalloc(sizeof(struct page *) * max_cluster,
1144 GFP_NOFS);
1145 if (!pages) {
1146 ret = -ENOMEM;
1147 goto out_ra;
1148 }
1149
1150 /* find the last page to defrag */
1151 if (range->start + range->len > range->start) {
1152 last_index = min_t(u64, isize - 1,
1153 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1154 } else {
1155 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1156 }
1157
1158 if (newer_than) {
1159 ret = find_new_extents(root, inode, newer_than,
1160 &newer_off, 64 * 1024);
1161 if (!ret) {
1162 range->start = newer_off;
1163 /*
1164 * we always align our defrag to help keep
1165 * the extents in the file evenly spaced
1166 */
1167 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1168 } else
1169 goto out_ra;
1170 } else {
1171 i = range->start >> PAGE_CACHE_SHIFT;
1172 }
1173 if (!max_to_defrag)
1174 max_to_defrag = last_index + 1;
1175
1176 /*
1177 * make writeback starts from i, so the defrag range can be
1178 * written sequentially.
1179 */
1180 if (i < inode->i_mapping->writeback_index)
1181 inode->i_mapping->writeback_index = i;
1182
1183 while (i <= last_index && defrag_count < max_to_defrag &&
1184 (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1185 PAGE_CACHE_SHIFT)) {
1186 /*
1187 * make sure we stop running if someone unmounts
1188 * the FS
1189 */
1190 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1191 break;
1192
1193 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1194 extent_thresh, &last_len, &skip,
1195 &defrag_end, range->flags &
1196 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1197 unsigned long next;
1198 /*
1199 * the should_defrag function tells us how much to skip
1200 * bump our counter by the suggested amount
1201 */
1202 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1203 i = max(i + 1, next);
1204 continue;
1205 }
1206
1207 if (!newer_than) {
1208 cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1209 PAGE_CACHE_SHIFT) - i;
1210 cluster = min(cluster, max_cluster);
1211 } else {
1212 cluster = max_cluster;
1213 }
1214
1215 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1216 BTRFS_I(inode)->force_compress = compress_type;
1217
1218 if (i + cluster > ra_index) {
1219 ra_index = max(i, ra_index);
1220 btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1221 cluster);
1222 ra_index += max_cluster;
1223 }
1224
1225 mutex_lock(&inode->i_mutex);
1226 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1227 if (ret < 0) {
1228 mutex_unlock(&inode->i_mutex);
1229 goto out_ra;
1230 }
1231
1232 defrag_count += ret;
1233 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
1234 mutex_unlock(&inode->i_mutex);
1235
1236 if (newer_than) {
1237 if (newer_off == (u64)-1)
1238 break;
1239
1240 if (ret > 0)
1241 i += ret;
1242
1243 newer_off = max(newer_off + 1,
1244 (u64)i << PAGE_CACHE_SHIFT);
1245
1246 ret = find_new_extents(root, inode,
1247 newer_than, &newer_off,
1248 64 * 1024);
1249 if (!ret) {
1250 range->start = newer_off;
1251 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1252 } else {
1253 break;
1254 }
1255 } else {
1256 if (ret > 0) {
1257 i += ret;
1258 last_len += ret << PAGE_CACHE_SHIFT;
1259 } else {
1260 i++;
1261 last_len = 0;
1262 }
1263 }
1264 }
1265
1266 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1267 filemap_flush(inode->i_mapping);
1268
1269 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1270 /* the filemap_flush will queue IO into the worker threads, but
1271 * we have to make sure the IO is actually started and that
1272 * ordered extents get created before we return
1273 */
1274 atomic_inc(&root->fs_info->async_submit_draining);
1275 while (atomic_read(&root->fs_info->nr_async_submits) ||
1276 atomic_read(&root->fs_info->async_delalloc_pages)) {
1277 wait_event(root->fs_info->async_submit_wait,
1278 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1279 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1280 }
1281 atomic_dec(&root->fs_info->async_submit_draining);
1282
1283 mutex_lock(&inode->i_mutex);
1284 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1285 mutex_unlock(&inode->i_mutex);
1286 }
1287
1288 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1289 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1290 }
1291
1292 ret = defrag_count;
1293
1294 out_ra:
1295 if (!file)
1296 kfree(ra);
1297 kfree(pages);
1298 return ret;
1299 }
1300
1301 static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
1302 void __user *arg)
1303 {
1304 u64 new_size;
1305 u64 old_size;
1306 u64 devid = 1;
1307 struct btrfs_ioctl_vol_args *vol_args;
1308 struct btrfs_trans_handle *trans;
1309 struct btrfs_device *device = NULL;
1310 char *sizestr;
1311 char *devstr = NULL;
1312 int ret = 0;
1313 int mod = 0;
1314
1315 if (root->fs_info->sb->s_flags & MS_RDONLY)
1316 return -EROFS;
1317
1318 if (!capable(CAP_SYS_ADMIN))
1319 return -EPERM;
1320
1321 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1322 1)) {
1323 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
1324 return -EINPROGRESS;
1325 }
1326
1327 mutex_lock(&root->fs_info->volume_mutex);
1328 vol_args = memdup_user(arg, sizeof(*vol_args));
1329 if (IS_ERR(vol_args)) {
1330 ret = PTR_ERR(vol_args);
1331 goto out;
1332 }
1333
1334 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1335
1336 sizestr = vol_args->name;
1337 devstr = strchr(sizestr, ':');
1338 if (devstr) {
1339 char *end;
1340 sizestr = devstr + 1;
1341 *devstr = '\0';
1342 devstr = vol_args->name;
1343 devid = simple_strtoull(devstr, &end, 10);
1344 printk(KERN_INFO "btrfs: resizing devid %llu\n",
1345 (unsigned long long)devid);
1346 }
1347 device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1348 if (!device) {
1349 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n",
1350 (unsigned long long)devid);
1351 ret = -EINVAL;
1352 goto out_free;
1353 }
1354 if (device->fs_devices && device->fs_devices->seeding) {
1355 printk(KERN_INFO "btrfs: resizer unable to apply on "
1356 "seeding device %llu\n",
1357 (unsigned long long)devid);
1358 ret = -EINVAL;
1359 goto out_free;
1360 }
1361
1362 if (!strcmp(sizestr, "max"))
1363 new_size = device->bdev->bd_inode->i_size;
1364 else {
1365 if (sizestr[0] == '-') {
1366 mod = -1;
1367 sizestr++;
1368 } else if (sizestr[0] == '+') {
1369 mod = 1;
1370 sizestr++;
1371 }
1372 new_size = memparse(sizestr, NULL);
1373 if (new_size == 0) {
1374 ret = -EINVAL;
1375 goto out_free;
1376 }
1377 }
1378
1379 if (device->is_tgtdev_for_dev_replace) {
1380 ret = -EINVAL;
1381 goto out_free;
1382 }
1383
1384 old_size = device->total_bytes;
1385
1386 if (mod < 0) {
1387 if (new_size > old_size) {
1388 ret = -EINVAL;
1389 goto out_free;
1390 }
1391 new_size = old_size - new_size;
1392 } else if (mod > 0) {
1393 new_size = old_size + new_size;
1394 }
1395
1396 if (new_size < 256 * 1024 * 1024) {
1397 ret = -EINVAL;
1398 goto out_free;
1399 }
1400 if (new_size > device->bdev->bd_inode->i_size) {
1401 ret = -EFBIG;
1402 goto out_free;
1403 }
1404
1405 do_div(new_size, root->sectorsize);
1406 new_size *= root->sectorsize;
1407
1408 printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n",
1409 rcu_str_deref(device->name),
1410 (unsigned long long)new_size);
1411
1412 if (new_size > old_size) {
1413 trans = btrfs_start_transaction(root, 0);
1414 if (IS_ERR(trans)) {
1415 ret = PTR_ERR(trans);
1416 goto out_free;
1417 }
1418 ret = btrfs_grow_device(trans, device, new_size);
1419 btrfs_commit_transaction(trans, root);
1420 } else if (new_size < old_size) {
1421 ret = btrfs_shrink_device(device, new_size);
1422 } /* equal, nothing need to do */
1423
1424 out_free:
1425 kfree(vol_args);
1426 out:
1427 mutex_unlock(&root->fs_info->volume_mutex);
1428 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1429 return ret;
1430 }
1431
1432 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1433 char *name, unsigned long fd, int subvol,
1434 u64 *transid, bool readonly,
1435 struct btrfs_qgroup_inherit **inherit)
1436 {
1437 int namelen;
1438 int ret = 0;
1439
1440 ret = mnt_want_write_file(file);
1441 if (ret)
1442 goto out;
1443
1444 namelen = strlen(name);
1445 if (strchr(name, '/')) {
1446 ret = -EINVAL;
1447 goto out_drop_write;
1448 }
1449
1450 if (name[0] == '.' &&
1451 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1452 ret = -EEXIST;
1453 goto out_drop_write;
1454 }
1455
1456 if (subvol) {
1457 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1458 NULL, transid, readonly, inherit);
1459 } else {
1460 struct fd src = fdget(fd);
1461 struct inode *src_inode;
1462 if (!src.file) {
1463 ret = -EINVAL;
1464 goto out_drop_write;
1465 }
1466
1467 src_inode = src.file->f_path.dentry->d_inode;
1468 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1469 printk(KERN_INFO "btrfs: Snapshot src from "
1470 "another FS\n");
1471 ret = -EINVAL;
1472 } else {
1473 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1474 BTRFS_I(src_inode)->root,
1475 transid, readonly, inherit);
1476 }
1477 fdput(src);
1478 }
1479 out_drop_write:
1480 mnt_drop_write_file(file);
1481 out:
1482 return ret;
1483 }
1484
1485 static noinline int btrfs_ioctl_snap_create(struct file *file,
1486 void __user *arg, int subvol)
1487 {
1488 struct btrfs_ioctl_vol_args *vol_args;
1489 int ret;
1490
1491 vol_args = memdup_user(arg, sizeof(*vol_args));
1492 if (IS_ERR(vol_args))
1493 return PTR_ERR(vol_args);
1494 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1495
1496 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1497 vol_args->fd, subvol,
1498 NULL, false, NULL);
1499
1500 kfree(vol_args);
1501 return ret;
1502 }
1503
1504 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1505 void __user *arg, int subvol)
1506 {
1507 struct btrfs_ioctl_vol_args_v2 *vol_args;
1508 int ret;
1509 u64 transid = 0;
1510 u64 *ptr = NULL;
1511 bool readonly = false;
1512 struct btrfs_qgroup_inherit *inherit = NULL;
1513
1514 vol_args = memdup_user(arg, sizeof(*vol_args));
1515 if (IS_ERR(vol_args))
1516 return PTR_ERR(vol_args);
1517 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1518
1519 if (vol_args->flags &
1520 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1521 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1522 ret = -EOPNOTSUPP;
1523 goto out;
1524 }
1525
1526 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1527 ptr = &transid;
1528 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1529 readonly = true;
1530 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1531 if (vol_args->size > PAGE_CACHE_SIZE) {
1532 ret = -EINVAL;
1533 goto out;
1534 }
1535 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1536 if (IS_ERR(inherit)) {
1537 ret = PTR_ERR(inherit);
1538 goto out;
1539 }
1540 }
1541
1542 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1543 vol_args->fd, subvol, ptr,
1544 readonly, &inherit);
1545
1546 if (ret == 0 && ptr &&
1547 copy_to_user(arg +
1548 offsetof(struct btrfs_ioctl_vol_args_v2,
1549 transid), ptr, sizeof(*ptr)))
1550 ret = -EFAULT;
1551 out:
1552 kfree(vol_args);
1553 kfree(inherit);
1554 return ret;
1555 }
1556
1557 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1558 void __user *arg)
1559 {
1560 struct inode *inode = fdentry(file)->d_inode;
1561 struct btrfs_root *root = BTRFS_I(inode)->root;
1562 int ret = 0;
1563 u64 flags = 0;
1564
1565 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1566 return -EINVAL;
1567
1568 down_read(&root->fs_info->subvol_sem);
1569 if (btrfs_root_readonly(root))
1570 flags |= BTRFS_SUBVOL_RDONLY;
1571 up_read(&root->fs_info->subvol_sem);
1572
1573 if (copy_to_user(arg, &flags, sizeof(flags)))
1574 ret = -EFAULT;
1575
1576 return ret;
1577 }
1578
1579 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1580 void __user *arg)
1581 {
1582 struct inode *inode = fdentry(file)->d_inode;
1583 struct btrfs_root *root = BTRFS_I(inode)->root;
1584 struct btrfs_trans_handle *trans;
1585 u64 root_flags;
1586 u64 flags;
1587 int ret = 0;
1588
1589 ret = mnt_want_write_file(file);
1590 if (ret)
1591 goto out;
1592
1593 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1594 ret = -EINVAL;
1595 goto out_drop_write;
1596 }
1597
1598 if (copy_from_user(&flags, arg, sizeof(flags))) {
1599 ret = -EFAULT;
1600 goto out_drop_write;
1601 }
1602
1603 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1604 ret = -EINVAL;
1605 goto out_drop_write;
1606 }
1607
1608 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1609 ret = -EOPNOTSUPP;
1610 goto out_drop_write;
1611 }
1612
1613 if (!inode_owner_or_capable(inode)) {
1614 ret = -EACCES;
1615 goto out_drop_write;
1616 }
1617
1618 down_write(&root->fs_info->subvol_sem);
1619
1620 /* nothing to do */
1621 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1622 goto out_drop_sem;
1623
1624 root_flags = btrfs_root_flags(&root->root_item);
1625 if (flags & BTRFS_SUBVOL_RDONLY)
1626 btrfs_set_root_flags(&root->root_item,
1627 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1628 else
1629 btrfs_set_root_flags(&root->root_item,
1630 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1631
1632 trans = btrfs_start_transaction(root, 1);
1633 if (IS_ERR(trans)) {
1634 ret = PTR_ERR(trans);
1635 goto out_reset;
1636 }
1637
1638 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1639 &root->root_key, &root->root_item);
1640
1641 btrfs_commit_transaction(trans, root);
1642 out_reset:
1643 if (ret)
1644 btrfs_set_root_flags(&root->root_item, root_flags);
1645 out_drop_sem:
1646 up_write(&root->fs_info->subvol_sem);
1647 out_drop_write:
1648 mnt_drop_write_file(file);
1649 out:
1650 return ret;
1651 }
1652
1653 /*
1654 * helper to check if the subvolume references other subvolumes
1655 */
1656 static noinline int may_destroy_subvol(struct btrfs_root *root)
1657 {
1658 struct btrfs_path *path;
1659 struct btrfs_key key;
1660 int ret;
1661
1662 path = btrfs_alloc_path();
1663 if (!path)
1664 return -ENOMEM;
1665
1666 key.objectid = root->root_key.objectid;
1667 key.type = BTRFS_ROOT_REF_KEY;
1668 key.offset = (u64)-1;
1669
1670 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1671 &key, path, 0, 0);
1672 if (ret < 0)
1673 goto out;
1674 BUG_ON(ret == 0);
1675
1676 ret = 0;
1677 if (path->slots[0] > 0) {
1678 path->slots[0]--;
1679 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1680 if (key.objectid == root->root_key.objectid &&
1681 key.type == BTRFS_ROOT_REF_KEY)
1682 ret = -ENOTEMPTY;
1683 }
1684 out:
1685 btrfs_free_path(path);
1686 return ret;
1687 }
1688
1689 static noinline int key_in_sk(struct btrfs_key *key,
1690 struct btrfs_ioctl_search_key *sk)
1691 {
1692 struct btrfs_key test;
1693 int ret;
1694
1695 test.objectid = sk->min_objectid;
1696 test.type = sk->min_type;
1697 test.offset = sk->min_offset;
1698
1699 ret = btrfs_comp_cpu_keys(key, &test);
1700 if (ret < 0)
1701 return 0;
1702
1703 test.objectid = sk->max_objectid;
1704 test.type = sk->max_type;
1705 test.offset = sk->max_offset;
1706
1707 ret = btrfs_comp_cpu_keys(key, &test);
1708 if (ret > 0)
1709 return 0;
1710 return 1;
1711 }
1712
1713 static noinline int copy_to_sk(struct btrfs_root *root,
1714 struct btrfs_path *path,
1715 struct btrfs_key *key,
1716 struct btrfs_ioctl_search_key *sk,
1717 char *buf,
1718 unsigned long *sk_offset,
1719 int *num_found)
1720 {
1721 u64 found_transid;
1722 struct extent_buffer *leaf;
1723 struct btrfs_ioctl_search_header sh;
1724 unsigned long item_off;
1725 unsigned long item_len;
1726 int nritems;
1727 int i;
1728 int slot;
1729 int ret = 0;
1730
1731 leaf = path->nodes[0];
1732 slot = path->slots[0];
1733 nritems = btrfs_header_nritems(leaf);
1734
1735 if (btrfs_header_generation(leaf) > sk->max_transid) {
1736 i = nritems;
1737 goto advance_key;
1738 }
1739 found_transid = btrfs_header_generation(leaf);
1740
1741 for (i = slot; i < nritems; i++) {
1742 item_off = btrfs_item_ptr_offset(leaf, i);
1743 item_len = btrfs_item_size_nr(leaf, i);
1744
1745 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1746 item_len = 0;
1747
1748 if (sizeof(sh) + item_len + *sk_offset >
1749 BTRFS_SEARCH_ARGS_BUFSIZE) {
1750 ret = 1;
1751 goto overflow;
1752 }
1753
1754 btrfs_item_key_to_cpu(leaf, key, i);
1755 if (!key_in_sk(key, sk))
1756 continue;
1757
1758 sh.objectid = key->objectid;
1759 sh.offset = key->offset;
1760 sh.type = key->type;
1761 sh.len = item_len;
1762 sh.transid = found_transid;
1763
1764 /* copy search result header */
1765 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1766 *sk_offset += sizeof(sh);
1767
1768 if (item_len) {
1769 char *p = buf + *sk_offset;
1770 /* copy the item */
1771 read_extent_buffer(leaf, p,
1772 item_off, item_len);
1773 *sk_offset += item_len;
1774 }
1775 (*num_found)++;
1776
1777 if (*num_found >= sk->nr_items)
1778 break;
1779 }
1780 advance_key:
1781 ret = 0;
1782 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1783 key->offset++;
1784 else if (key->type < (u8)-1 && key->type < sk->max_type) {
1785 key->offset = 0;
1786 key->type++;
1787 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1788 key->offset = 0;
1789 key->type = 0;
1790 key->objectid++;
1791 } else
1792 ret = 1;
1793 overflow:
1794 return ret;
1795 }
1796
1797 static noinline int search_ioctl(struct inode *inode,
1798 struct btrfs_ioctl_search_args *args)
1799 {
1800 struct btrfs_root *root;
1801 struct btrfs_key key;
1802 struct btrfs_key max_key;
1803 struct btrfs_path *path;
1804 struct btrfs_ioctl_search_key *sk = &args->key;
1805 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1806 int ret;
1807 int num_found = 0;
1808 unsigned long sk_offset = 0;
1809
1810 path = btrfs_alloc_path();
1811 if (!path)
1812 return -ENOMEM;
1813
1814 if (sk->tree_id == 0) {
1815 /* search the root of the inode that was passed */
1816 root = BTRFS_I(inode)->root;
1817 } else {
1818 key.objectid = sk->tree_id;
1819 key.type = BTRFS_ROOT_ITEM_KEY;
1820 key.offset = (u64)-1;
1821 root = btrfs_read_fs_root_no_name(info, &key);
1822 if (IS_ERR(root)) {
1823 printk(KERN_ERR "could not find root %llu\n",
1824 sk->tree_id);
1825 btrfs_free_path(path);
1826 return -ENOENT;
1827 }
1828 }
1829
1830 key.objectid = sk->min_objectid;
1831 key.type = sk->min_type;
1832 key.offset = sk->min_offset;
1833
1834 max_key.objectid = sk->max_objectid;
1835 max_key.type = sk->max_type;
1836 max_key.offset = sk->max_offset;
1837
1838 path->keep_locks = 1;
1839
1840 while(1) {
1841 ret = btrfs_search_forward(root, &key, &max_key, path, 0,
1842 sk->min_transid);
1843 if (ret != 0) {
1844 if (ret > 0)
1845 ret = 0;
1846 goto err;
1847 }
1848 ret = copy_to_sk(root, path, &key, sk, args->buf,
1849 &sk_offset, &num_found);
1850 btrfs_release_path(path);
1851 if (ret || num_found >= sk->nr_items)
1852 break;
1853
1854 }
1855 ret = 0;
1856 err:
1857 sk->nr_items = num_found;
1858 btrfs_free_path(path);
1859 return ret;
1860 }
1861
1862 static noinline int btrfs_ioctl_tree_search(struct file *file,
1863 void __user *argp)
1864 {
1865 struct btrfs_ioctl_search_args *args;
1866 struct inode *inode;
1867 int ret;
1868
1869 if (!capable(CAP_SYS_ADMIN))
1870 return -EPERM;
1871
1872 args = memdup_user(argp, sizeof(*args));
1873 if (IS_ERR(args))
1874 return PTR_ERR(args);
1875
1876 inode = fdentry(file)->d_inode;
1877 ret = search_ioctl(inode, args);
1878 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1879 ret = -EFAULT;
1880 kfree(args);
1881 return ret;
1882 }
1883
1884 /*
1885 * Search INODE_REFs to identify path name of 'dirid' directory
1886 * in a 'tree_id' tree. and sets path name to 'name'.
1887 */
1888 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1889 u64 tree_id, u64 dirid, char *name)
1890 {
1891 struct btrfs_root *root;
1892 struct btrfs_key key;
1893 char *ptr;
1894 int ret = -1;
1895 int slot;
1896 int len;
1897 int total_len = 0;
1898 struct btrfs_inode_ref *iref;
1899 struct extent_buffer *l;
1900 struct btrfs_path *path;
1901
1902 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1903 name[0]='\0';
1904 return 0;
1905 }
1906
1907 path = btrfs_alloc_path();
1908 if (!path)
1909 return -ENOMEM;
1910
1911 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1912
1913 key.objectid = tree_id;
1914 key.type = BTRFS_ROOT_ITEM_KEY;
1915 key.offset = (u64)-1;
1916 root = btrfs_read_fs_root_no_name(info, &key);
1917 if (IS_ERR(root)) {
1918 printk(KERN_ERR "could not find root %llu\n", tree_id);
1919 ret = -ENOENT;
1920 goto out;
1921 }
1922
1923 key.objectid = dirid;
1924 key.type = BTRFS_INODE_REF_KEY;
1925 key.offset = (u64)-1;
1926
1927 while(1) {
1928 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1929 if (ret < 0)
1930 goto out;
1931
1932 l = path->nodes[0];
1933 slot = path->slots[0];
1934 if (ret > 0 && slot > 0)
1935 slot--;
1936 btrfs_item_key_to_cpu(l, &key, slot);
1937
1938 if (ret > 0 && (key.objectid != dirid ||
1939 key.type != BTRFS_INODE_REF_KEY)) {
1940 ret = -ENOENT;
1941 goto out;
1942 }
1943
1944 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1945 len = btrfs_inode_ref_name_len(l, iref);
1946 ptr -= len + 1;
1947 total_len += len + 1;
1948 if (ptr < name)
1949 goto out;
1950
1951 *(ptr + len) = '/';
1952 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1953
1954 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1955 break;
1956
1957 btrfs_release_path(path);
1958 key.objectid = key.offset;
1959 key.offset = (u64)-1;
1960 dirid = key.objectid;
1961 }
1962 if (ptr < name)
1963 goto out;
1964 memmove(name, ptr, total_len);
1965 name[total_len]='\0';
1966 ret = 0;
1967 out:
1968 btrfs_free_path(path);
1969 return ret;
1970 }
1971
1972 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
1973 void __user *argp)
1974 {
1975 struct btrfs_ioctl_ino_lookup_args *args;
1976 struct inode *inode;
1977 int ret;
1978
1979 if (!capable(CAP_SYS_ADMIN))
1980 return -EPERM;
1981
1982 args = memdup_user(argp, sizeof(*args));
1983 if (IS_ERR(args))
1984 return PTR_ERR(args);
1985
1986 inode = fdentry(file)->d_inode;
1987
1988 if (args->treeid == 0)
1989 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
1990
1991 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
1992 args->treeid, args->objectid,
1993 args->name);
1994
1995 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1996 ret = -EFAULT;
1997
1998 kfree(args);
1999 return ret;
2000 }
2001
2002 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2003 void __user *arg)
2004 {
2005 struct dentry *parent = fdentry(file);
2006 struct dentry *dentry;
2007 struct inode *dir = parent->d_inode;
2008 struct inode *inode;
2009 struct btrfs_root *root = BTRFS_I(dir)->root;
2010 struct btrfs_root *dest = NULL;
2011 struct btrfs_ioctl_vol_args *vol_args;
2012 struct btrfs_trans_handle *trans;
2013 int namelen;
2014 int ret;
2015 int err = 0;
2016
2017 vol_args = memdup_user(arg, sizeof(*vol_args));
2018 if (IS_ERR(vol_args))
2019 return PTR_ERR(vol_args);
2020
2021 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2022 namelen = strlen(vol_args->name);
2023 if (strchr(vol_args->name, '/') ||
2024 strncmp(vol_args->name, "..", namelen) == 0) {
2025 err = -EINVAL;
2026 goto out;
2027 }
2028
2029 err = mnt_want_write_file(file);
2030 if (err)
2031 goto out;
2032
2033 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
2034 dentry = lookup_one_len(vol_args->name, parent, namelen);
2035 if (IS_ERR(dentry)) {
2036 err = PTR_ERR(dentry);
2037 goto out_unlock_dir;
2038 }
2039
2040 if (!dentry->d_inode) {
2041 err = -ENOENT;
2042 goto out_dput;
2043 }
2044
2045 inode = dentry->d_inode;
2046 dest = BTRFS_I(inode)->root;
2047 if (!capable(CAP_SYS_ADMIN)){
2048 /*
2049 * Regular user. Only allow this with a special mount
2050 * option, when the user has write+exec access to the
2051 * subvol root, and when rmdir(2) would have been
2052 * allowed.
2053 *
2054 * Note that this is _not_ check that the subvol is
2055 * empty or doesn't contain data that we wouldn't
2056 * otherwise be able to delete.
2057 *
2058 * Users who want to delete empty subvols should try
2059 * rmdir(2).
2060 */
2061 err = -EPERM;
2062 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2063 goto out_dput;
2064
2065 /*
2066 * Do not allow deletion if the parent dir is the same
2067 * as the dir to be deleted. That means the ioctl
2068 * must be called on the dentry referencing the root
2069 * of the subvol, not a random directory contained
2070 * within it.
2071 */
2072 err = -EINVAL;
2073 if (root == dest)
2074 goto out_dput;
2075
2076 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2077 if (err)
2078 goto out_dput;
2079
2080 /* check if subvolume may be deleted by a non-root user */
2081 err = btrfs_may_delete(dir, dentry, 1);
2082 if (err)
2083 goto out_dput;
2084 }
2085
2086 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2087 err = -EINVAL;
2088 goto out_dput;
2089 }
2090
2091 mutex_lock(&inode->i_mutex);
2092 err = d_invalidate(dentry);
2093 if (err)
2094 goto out_unlock;
2095
2096 down_write(&root->fs_info->subvol_sem);
2097
2098 err = may_destroy_subvol(dest);
2099 if (err)
2100 goto out_up_write;
2101
2102 trans = btrfs_start_transaction(root, 0);
2103 if (IS_ERR(trans)) {
2104 err = PTR_ERR(trans);
2105 goto out_up_write;
2106 }
2107 trans->block_rsv = &root->fs_info->global_block_rsv;
2108
2109 ret = btrfs_unlink_subvol(trans, root, dir,
2110 dest->root_key.objectid,
2111 dentry->d_name.name,
2112 dentry->d_name.len);
2113 if (ret) {
2114 err = ret;
2115 btrfs_abort_transaction(trans, root, ret);
2116 goto out_end_trans;
2117 }
2118
2119 btrfs_record_root_in_trans(trans, dest);
2120
2121 memset(&dest->root_item.drop_progress, 0,
2122 sizeof(dest->root_item.drop_progress));
2123 dest->root_item.drop_level = 0;
2124 btrfs_set_root_refs(&dest->root_item, 0);
2125
2126 if (!xchg(&dest->orphan_item_inserted, 1)) {
2127 ret = btrfs_insert_orphan_item(trans,
2128 root->fs_info->tree_root,
2129 dest->root_key.objectid);
2130 if (ret) {
2131 btrfs_abort_transaction(trans, root, ret);
2132 err = ret;
2133 goto out_end_trans;
2134 }
2135 }
2136 out_end_trans:
2137 ret = btrfs_end_transaction(trans, root);
2138 if (ret && !err)
2139 err = ret;
2140 inode->i_flags |= S_DEAD;
2141 out_up_write:
2142 up_write(&root->fs_info->subvol_sem);
2143 out_unlock:
2144 mutex_unlock(&inode->i_mutex);
2145 if (!err) {
2146 shrink_dcache_sb(root->fs_info->sb);
2147 btrfs_invalidate_inodes(dest);
2148 d_delete(dentry);
2149 }
2150 out_dput:
2151 dput(dentry);
2152 out_unlock_dir:
2153 mutex_unlock(&dir->i_mutex);
2154 mnt_drop_write_file(file);
2155 out:
2156 kfree(vol_args);
2157 return err;
2158 }
2159
2160 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2161 {
2162 struct inode *inode = fdentry(file)->d_inode;
2163 struct btrfs_root *root = BTRFS_I(inode)->root;
2164 struct btrfs_ioctl_defrag_range_args *range;
2165 int ret;
2166
2167 if (btrfs_root_readonly(root))
2168 return -EROFS;
2169
2170 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2171 1)) {
2172 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
2173 return -EINPROGRESS;
2174 }
2175 ret = mnt_want_write_file(file);
2176 if (ret) {
2177 atomic_set(&root->fs_info->mutually_exclusive_operation_running,
2178 0);
2179 return ret;
2180 }
2181
2182 switch (inode->i_mode & S_IFMT) {
2183 case S_IFDIR:
2184 if (!capable(CAP_SYS_ADMIN)) {
2185 ret = -EPERM;
2186 goto out;
2187 }
2188 ret = btrfs_defrag_root(root, 0);
2189 if (ret)
2190 goto out;
2191 ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
2192 break;
2193 case S_IFREG:
2194 if (!(file->f_mode & FMODE_WRITE)) {
2195 ret = -EINVAL;
2196 goto out;
2197 }
2198
2199 range = kzalloc(sizeof(*range), GFP_KERNEL);
2200 if (!range) {
2201 ret = -ENOMEM;
2202 goto out;
2203 }
2204
2205 if (argp) {
2206 if (copy_from_user(range, argp,
2207 sizeof(*range))) {
2208 ret = -EFAULT;
2209 kfree(range);
2210 goto out;
2211 }
2212 /* compression requires us to start the IO */
2213 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2214 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2215 range->extent_thresh = (u32)-1;
2216 }
2217 } else {
2218 /* the rest are all set to zero by kzalloc */
2219 range->len = (u64)-1;
2220 }
2221 ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
2222 range, 0, 0);
2223 if (ret > 0)
2224 ret = 0;
2225 kfree(range);
2226 break;
2227 default:
2228 ret = -EINVAL;
2229 }
2230 out:
2231 mnt_drop_write_file(file);
2232 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2233 return ret;
2234 }
2235
2236 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2237 {
2238 struct btrfs_ioctl_vol_args *vol_args;
2239 int ret;
2240
2241 if (!capable(CAP_SYS_ADMIN))
2242 return -EPERM;
2243
2244 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2245 1)) {
2246 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
2247 return -EINPROGRESS;
2248 }
2249
2250 mutex_lock(&root->fs_info->volume_mutex);
2251 vol_args = memdup_user(arg, sizeof(*vol_args));
2252 if (IS_ERR(vol_args)) {
2253 ret = PTR_ERR(vol_args);
2254 goto out;
2255 }
2256
2257 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2258 ret = btrfs_init_new_device(root, vol_args->name);
2259
2260 kfree(vol_args);
2261 out:
2262 mutex_unlock(&root->fs_info->volume_mutex);
2263 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2264 return ret;
2265 }
2266
2267 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
2268 {
2269 struct btrfs_ioctl_vol_args *vol_args;
2270 int ret;
2271
2272 if (!capable(CAP_SYS_ADMIN))
2273 return -EPERM;
2274
2275 if (root->fs_info->sb->s_flags & MS_RDONLY)
2276 return -EROFS;
2277
2278 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2279 1)) {
2280 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
2281 return -EINPROGRESS;
2282 }
2283
2284 mutex_lock(&root->fs_info->volume_mutex);
2285 vol_args = memdup_user(arg, sizeof(*vol_args));
2286 if (IS_ERR(vol_args)) {
2287 ret = PTR_ERR(vol_args);
2288 goto out;
2289 }
2290
2291 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2292 ret = btrfs_rm_device(root, vol_args->name);
2293
2294 kfree(vol_args);
2295 out:
2296 mutex_unlock(&root->fs_info->volume_mutex);
2297 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2298 return ret;
2299 }
2300
2301 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2302 {
2303 struct btrfs_ioctl_fs_info_args *fi_args;
2304 struct btrfs_device *device;
2305 struct btrfs_device *next;
2306 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2307 int ret = 0;
2308
2309 if (!capable(CAP_SYS_ADMIN))
2310 return -EPERM;
2311
2312 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2313 if (!fi_args)
2314 return -ENOMEM;
2315
2316 fi_args->num_devices = fs_devices->num_devices;
2317 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2318
2319 mutex_lock(&fs_devices->device_list_mutex);
2320 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2321 if (device->devid > fi_args->max_id)
2322 fi_args->max_id = device->devid;
2323 }
2324 mutex_unlock(&fs_devices->device_list_mutex);
2325
2326 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2327 ret = -EFAULT;
2328
2329 kfree(fi_args);
2330 return ret;
2331 }
2332
2333 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2334 {
2335 struct btrfs_ioctl_dev_info_args *di_args;
2336 struct btrfs_device *dev;
2337 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2338 int ret = 0;
2339 char *s_uuid = NULL;
2340 char empty_uuid[BTRFS_UUID_SIZE] = {0};
2341
2342 if (!capable(CAP_SYS_ADMIN))
2343 return -EPERM;
2344
2345 di_args = memdup_user(arg, sizeof(*di_args));
2346 if (IS_ERR(di_args))
2347 return PTR_ERR(di_args);
2348
2349 if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2350 s_uuid = di_args->uuid;
2351
2352 mutex_lock(&fs_devices->device_list_mutex);
2353 dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2354 mutex_unlock(&fs_devices->device_list_mutex);
2355
2356 if (!dev) {
2357 ret = -ENODEV;
2358 goto out;
2359 }
2360
2361 di_args->devid = dev->devid;
2362 di_args->bytes_used = dev->bytes_used;
2363 di_args->total_bytes = dev->total_bytes;
2364 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2365 if (dev->name) {
2366 struct rcu_string *name;
2367
2368 rcu_read_lock();
2369 name = rcu_dereference(dev->name);
2370 strncpy(di_args->path, name->str, sizeof(di_args->path));
2371 rcu_read_unlock();
2372 di_args->path[sizeof(di_args->path) - 1] = 0;
2373 } else {
2374 di_args->path[0] = '\0';
2375 }
2376
2377 out:
2378 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2379 ret = -EFAULT;
2380
2381 kfree(di_args);
2382 return ret;
2383 }
2384
2385 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2386 u64 off, u64 olen, u64 destoff)
2387 {
2388 struct inode *inode = fdentry(file)->d_inode;
2389 struct btrfs_root *root = BTRFS_I(inode)->root;
2390 struct fd src_file;
2391 struct inode *src;
2392 struct btrfs_trans_handle *trans;
2393 struct btrfs_path *path;
2394 struct extent_buffer *leaf;
2395 char *buf;
2396 struct btrfs_key key;
2397 u32 nritems;
2398 int slot;
2399 int ret;
2400 u64 len = olen;
2401 u64 bs = root->fs_info->sb->s_blocksize;
2402
2403 /*
2404 * TODO:
2405 * - split compressed inline extents. annoying: we need to
2406 * decompress into destination's address_space (the file offset
2407 * may change, so source mapping won't do), then recompress (or
2408 * otherwise reinsert) a subrange.
2409 * - allow ranges within the same file to be cloned (provided
2410 * they don't overlap)?
2411 */
2412
2413 /* the destination must be opened for writing */
2414 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2415 return -EINVAL;
2416
2417 if (btrfs_root_readonly(root))
2418 return -EROFS;
2419
2420 ret = mnt_want_write_file(file);
2421 if (ret)
2422 return ret;
2423
2424 src_file = fdget(srcfd);
2425 if (!src_file.file) {
2426 ret = -EBADF;
2427 goto out_drop_write;
2428 }
2429
2430 ret = -EXDEV;
2431 if (src_file.file->f_path.mnt != file->f_path.mnt)
2432 goto out_fput;
2433
2434 src = src_file.file->f_dentry->d_inode;
2435
2436 ret = -EINVAL;
2437 if (src == inode)
2438 goto out_fput;
2439
2440 /* the src must be open for reading */
2441 if (!(src_file.file->f_mode & FMODE_READ))
2442 goto out_fput;
2443
2444 /* don't make the dst file partly checksummed */
2445 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2446 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2447 goto out_fput;
2448
2449 ret = -EISDIR;
2450 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2451 goto out_fput;
2452
2453 ret = -EXDEV;
2454 if (src->i_sb != inode->i_sb)
2455 goto out_fput;
2456
2457 ret = -ENOMEM;
2458 buf = vmalloc(btrfs_level_size(root, 0));
2459 if (!buf)
2460 goto out_fput;
2461
2462 path = btrfs_alloc_path();
2463 if (!path) {
2464 vfree(buf);
2465 goto out_fput;
2466 }
2467 path->reada = 2;
2468
2469 if (inode < src) {
2470 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2471 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2472 } else {
2473 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2474 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2475 }
2476
2477 /* determine range to clone */
2478 ret = -EINVAL;
2479 if (off + len > src->i_size || off + len < off)
2480 goto out_unlock;
2481 if (len == 0)
2482 olen = len = src->i_size - off;
2483 /* if we extend to eof, continue to block boundary */
2484 if (off + len == src->i_size)
2485 len = ALIGN(src->i_size, bs) - off;
2486
2487 /* verify the end result is block aligned */
2488 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2489 !IS_ALIGNED(destoff, bs))
2490 goto out_unlock;
2491
2492 if (destoff > inode->i_size) {
2493 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2494 if (ret)
2495 goto out_unlock;
2496 }
2497
2498 /* truncate page cache pages from target inode range */
2499 truncate_inode_pages_range(&inode->i_data, destoff,
2500 PAGE_CACHE_ALIGN(destoff + len) - 1);
2501
2502 /* do any pending delalloc/csum calc on src, one way or
2503 another, and lock file content */
2504 while (1) {
2505 struct btrfs_ordered_extent *ordered;
2506 lock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
2507 ordered = btrfs_lookup_first_ordered_extent(src, off + len - 1);
2508 if (!ordered &&
2509 !test_range_bit(&BTRFS_I(src)->io_tree, off, off + len - 1,
2510 EXTENT_DELALLOC, 0, NULL))
2511 break;
2512 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
2513 if (ordered)
2514 btrfs_put_ordered_extent(ordered);
2515 btrfs_wait_ordered_range(src, off, len);
2516 }
2517
2518 /* clone data */
2519 key.objectid = btrfs_ino(src);
2520 key.type = BTRFS_EXTENT_DATA_KEY;
2521 key.offset = 0;
2522
2523 while (1) {
2524 /*
2525 * note the key will change type as we walk through the
2526 * tree.
2527 */
2528 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
2529 0, 0);
2530 if (ret < 0)
2531 goto out;
2532
2533 nritems = btrfs_header_nritems(path->nodes[0]);
2534 if (path->slots[0] >= nritems) {
2535 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
2536 if (ret < 0)
2537 goto out;
2538 if (ret > 0)
2539 break;
2540 nritems = btrfs_header_nritems(path->nodes[0]);
2541 }
2542 leaf = path->nodes[0];
2543 slot = path->slots[0];
2544
2545 btrfs_item_key_to_cpu(leaf, &key, slot);
2546 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2547 key.objectid != btrfs_ino(src))
2548 break;
2549
2550 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2551 struct btrfs_file_extent_item *extent;
2552 int type;
2553 u32 size;
2554 struct btrfs_key new_key;
2555 u64 disko = 0, diskl = 0;
2556 u64 datao = 0, datal = 0;
2557 u8 comp;
2558 u64 endoff;
2559
2560 size = btrfs_item_size_nr(leaf, slot);
2561 read_extent_buffer(leaf, buf,
2562 btrfs_item_ptr_offset(leaf, slot),
2563 size);
2564
2565 extent = btrfs_item_ptr(leaf, slot,
2566 struct btrfs_file_extent_item);
2567 comp = btrfs_file_extent_compression(leaf, extent);
2568 type = btrfs_file_extent_type(leaf, extent);
2569 if (type == BTRFS_FILE_EXTENT_REG ||
2570 type == BTRFS_FILE_EXTENT_PREALLOC) {
2571 disko = btrfs_file_extent_disk_bytenr(leaf,
2572 extent);
2573 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2574 extent);
2575 datao = btrfs_file_extent_offset(leaf, extent);
2576 datal = btrfs_file_extent_num_bytes(leaf,
2577 extent);
2578 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2579 /* take upper bound, may be compressed */
2580 datal = btrfs_file_extent_ram_bytes(leaf,
2581 extent);
2582 }
2583 btrfs_release_path(path);
2584
2585 if (key.offset + datal <= off ||
2586 key.offset >= off + len - 1)
2587 goto next;
2588
2589 memcpy(&new_key, &key, sizeof(new_key));
2590 new_key.objectid = btrfs_ino(inode);
2591 if (off <= key.offset)
2592 new_key.offset = key.offset + destoff - off;
2593 else
2594 new_key.offset = destoff;
2595
2596 /*
2597 * 1 - adjusting old extent (we may have to split it)
2598 * 1 - add new extent
2599 * 1 - inode update
2600 */
2601 trans = btrfs_start_transaction(root, 3);
2602 if (IS_ERR(trans)) {
2603 ret = PTR_ERR(trans);
2604 goto out;
2605 }
2606
2607 if (type == BTRFS_FILE_EXTENT_REG ||
2608 type == BTRFS_FILE_EXTENT_PREALLOC) {
2609 /*
2610 * a | --- range to clone ---| b
2611 * | ------------- extent ------------- |
2612 */
2613
2614 /* substract range b */
2615 if (key.offset + datal > off + len)
2616 datal = off + len - key.offset;
2617
2618 /* substract range a */
2619 if (off > key.offset) {
2620 datao += off - key.offset;
2621 datal -= off - key.offset;
2622 }
2623
2624 ret = btrfs_drop_extents(trans, root, inode,
2625 new_key.offset,
2626 new_key.offset + datal,
2627 1);
2628 if (ret) {
2629 btrfs_abort_transaction(trans, root,
2630 ret);
2631 btrfs_end_transaction(trans, root);
2632 goto out;
2633 }
2634
2635 ret = btrfs_insert_empty_item(trans, root, path,
2636 &new_key, size);
2637 if (ret) {
2638 btrfs_abort_transaction(trans, root,
2639 ret);
2640 btrfs_end_transaction(trans, root);
2641 goto out;
2642 }
2643
2644 leaf = path->nodes[0];
2645 slot = path->slots[0];
2646 write_extent_buffer(leaf, buf,
2647 btrfs_item_ptr_offset(leaf, slot),
2648 size);
2649
2650 extent = btrfs_item_ptr(leaf, slot,
2651 struct btrfs_file_extent_item);
2652
2653 /* disko == 0 means it's a hole */
2654 if (!disko)
2655 datao = 0;
2656
2657 btrfs_set_file_extent_offset(leaf, extent,
2658 datao);
2659 btrfs_set_file_extent_num_bytes(leaf, extent,
2660 datal);
2661 if (disko) {
2662 inode_add_bytes(inode, datal);
2663 ret = btrfs_inc_extent_ref(trans, root,
2664 disko, diskl, 0,
2665 root->root_key.objectid,
2666 btrfs_ino(inode),
2667 new_key.offset - datao,
2668 0);
2669 if (ret) {
2670 btrfs_abort_transaction(trans,
2671 root,
2672 ret);
2673 btrfs_end_transaction(trans,
2674 root);
2675 goto out;
2676
2677 }
2678 }
2679 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2680 u64 skip = 0;
2681 u64 trim = 0;
2682 if (off > key.offset) {
2683 skip = off - key.offset;
2684 new_key.offset += skip;
2685 }
2686
2687 if (key.offset + datal > off + len)
2688 trim = key.offset + datal - (off + len);
2689
2690 if (comp && (skip || trim)) {
2691 ret = -EINVAL;
2692 btrfs_end_transaction(trans, root);
2693 goto out;
2694 }
2695 size -= skip + trim;
2696 datal -= skip + trim;
2697
2698 ret = btrfs_drop_extents(trans, root, inode,
2699 new_key.offset,
2700 new_key.offset + datal,
2701 1);
2702 if (ret) {
2703 btrfs_abort_transaction(trans, root,
2704 ret);
2705 btrfs_end_transaction(trans, root);
2706 goto out;
2707 }
2708
2709 ret = btrfs_insert_empty_item(trans, root, path,
2710 &new_key, size);
2711 if (ret) {
2712 btrfs_abort_transaction(trans, root,
2713 ret);
2714 btrfs_end_transaction(trans, root);
2715 goto out;
2716 }
2717
2718 if (skip) {
2719 u32 start =
2720 btrfs_file_extent_calc_inline_size(0);
2721 memmove(buf+start, buf+start+skip,
2722 datal);
2723 }
2724
2725 leaf = path->nodes[0];
2726 slot = path->slots[0];
2727 write_extent_buffer(leaf, buf,
2728 btrfs_item_ptr_offset(leaf, slot),
2729 size);
2730 inode_add_bytes(inode, datal);
2731 }
2732
2733 btrfs_mark_buffer_dirty(leaf);
2734 btrfs_release_path(path);
2735
2736 inode_inc_iversion(inode);
2737 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2738
2739 /*
2740 * we round up to the block size at eof when
2741 * determining which extents to clone above,
2742 * but shouldn't round up the file size
2743 */
2744 endoff = new_key.offset + datal;
2745 if (endoff > destoff+olen)
2746 endoff = destoff+olen;
2747 if (endoff > inode->i_size)
2748 btrfs_i_size_write(inode, endoff);
2749
2750 ret = btrfs_update_inode(trans, root, inode);
2751 if (ret) {
2752 btrfs_abort_transaction(trans, root, ret);
2753 btrfs_end_transaction(trans, root);
2754 goto out;
2755 }
2756 ret = btrfs_end_transaction(trans, root);
2757 }
2758 next:
2759 btrfs_release_path(path);
2760 key.offset++;
2761 }
2762 ret = 0;
2763 out:
2764 btrfs_release_path(path);
2765 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
2766 out_unlock:
2767 mutex_unlock(&src->i_mutex);
2768 mutex_unlock(&inode->i_mutex);
2769 vfree(buf);
2770 btrfs_free_path(path);
2771 out_fput:
2772 fdput(src_file);
2773 out_drop_write:
2774 mnt_drop_write_file(file);
2775 return ret;
2776 }
2777
2778 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2779 {
2780 struct btrfs_ioctl_clone_range_args args;
2781
2782 if (copy_from_user(&args, argp, sizeof(args)))
2783 return -EFAULT;
2784 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2785 args.src_length, args.dest_offset);
2786 }
2787
2788 /*
2789 * there are many ways the trans_start and trans_end ioctls can lead
2790 * to deadlocks. They should only be used by applications that
2791 * basically own the machine, and have a very in depth understanding
2792 * of all the possible deadlocks and enospc problems.
2793 */
2794 static long btrfs_ioctl_trans_start(struct file *file)
2795 {
2796 struct inode *inode = fdentry(file)->d_inode;
2797 struct btrfs_root *root = BTRFS_I(inode)->root;
2798 struct btrfs_trans_handle *trans;
2799 int ret;
2800
2801 ret = -EPERM;
2802 if (!capable(CAP_SYS_ADMIN))
2803 goto out;
2804
2805 ret = -EINPROGRESS;
2806 if (file->private_data)
2807 goto out;
2808
2809 ret = -EROFS;
2810 if (btrfs_root_readonly(root))
2811 goto out;
2812
2813 ret = mnt_want_write_file(file);
2814 if (ret)
2815 goto out;
2816
2817 atomic_inc(&root->fs_info->open_ioctl_trans);
2818
2819 ret = -ENOMEM;
2820 trans = btrfs_start_ioctl_transaction(root);
2821 if (IS_ERR(trans))
2822 goto out_drop;
2823
2824 file->private_data = trans;
2825 return 0;
2826
2827 out_drop:
2828 atomic_dec(&root->fs_info->open_ioctl_trans);
2829 mnt_drop_write_file(file);
2830 out:
2831 return ret;
2832 }
2833
2834 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2835 {
2836 struct inode *inode = fdentry(file)->d_inode;
2837 struct btrfs_root *root = BTRFS_I(inode)->root;
2838 struct btrfs_root *new_root;
2839 struct btrfs_dir_item *di;
2840 struct btrfs_trans_handle *trans;
2841 struct btrfs_path *path;
2842 struct btrfs_key location;
2843 struct btrfs_disk_key disk_key;
2844 u64 objectid = 0;
2845 u64 dir_id;
2846
2847 if (!capable(CAP_SYS_ADMIN))
2848 return -EPERM;
2849
2850 if (copy_from_user(&objectid, argp, sizeof(objectid)))
2851 return -EFAULT;
2852
2853 if (!objectid)
2854 objectid = root->root_key.objectid;
2855
2856 location.objectid = objectid;
2857 location.type = BTRFS_ROOT_ITEM_KEY;
2858 location.offset = (u64)-1;
2859
2860 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2861 if (IS_ERR(new_root))
2862 return PTR_ERR(new_root);
2863
2864 if (btrfs_root_refs(&new_root->root_item) == 0)
2865 return -ENOENT;
2866
2867 path = btrfs_alloc_path();
2868 if (!path)
2869 return -ENOMEM;
2870 path->leave_spinning = 1;
2871
2872 trans = btrfs_start_transaction(root, 1);
2873 if (IS_ERR(trans)) {
2874 btrfs_free_path(path);
2875 return PTR_ERR(trans);
2876 }
2877
2878 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
2879 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2880 dir_id, "default", 7, 1);
2881 if (IS_ERR_OR_NULL(di)) {
2882 btrfs_free_path(path);
2883 btrfs_end_transaction(trans, root);
2884 printk(KERN_ERR "Umm, you don't have the default dir item, "
2885 "this isn't going to work\n");
2886 return -ENOENT;
2887 }
2888
2889 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2890 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2891 btrfs_mark_buffer_dirty(path->nodes[0]);
2892 btrfs_free_path(path);
2893
2894 btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
2895 btrfs_end_transaction(trans, root);
2896
2897 return 0;
2898 }
2899
2900 void btrfs_get_block_group_info(struct list_head *groups_list,
2901 struct btrfs_ioctl_space_info *space)
2902 {
2903 struct btrfs_block_group_cache *block_group;
2904
2905 space->total_bytes = 0;
2906 space->used_bytes = 0;
2907 space->flags = 0;
2908 list_for_each_entry(block_group, groups_list, list) {
2909 space->flags = block_group->flags;
2910 space->total_bytes += block_group->key.offset;
2911 space->used_bytes +=
2912 btrfs_block_group_used(&block_group->item);
2913 }
2914 }
2915
2916 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
2917 {
2918 struct btrfs_ioctl_space_args space_args;
2919 struct btrfs_ioctl_space_info space;
2920 struct btrfs_ioctl_space_info *dest;
2921 struct btrfs_ioctl_space_info *dest_orig;
2922 struct btrfs_ioctl_space_info __user *user_dest;
2923 struct btrfs_space_info *info;
2924 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2925 BTRFS_BLOCK_GROUP_SYSTEM,
2926 BTRFS_BLOCK_GROUP_METADATA,
2927 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
2928 int num_types = 4;
2929 int alloc_size;
2930 int ret = 0;
2931 u64 slot_count = 0;
2932 int i, c;
2933
2934 if (copy_from_user(&space_args,
2935 (struct btrfs_ioctl_space_args __user *)arg,
2936 sizeof(space_args)))
2937 return -EFAULT;
2938
2939 for (i = 0; i < num_types; i++) {
2940 struct btrfs_space_info *tmp;
2941
2942 info = NULL;
2943 rcu_read_lock();
2944 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2945 list) {
2946 if (tmp->flags == types[i]) {
2947 info = tmp;
2948 break;
2949 }
2950 }
2951 rcu_read_unlock();
2952
2953 if (!info)
2954 continue;
2955
2956 down_read(&info->groups_sem);
2957 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2958 if (!list_empty(&info->block_groups[c]))
2959 slot_count++;
2960 }
2961 up_read(&info->groups_sem);
2962 }
2963
2964 /* space_slots == 0 means they are asking for a count */
2965 if (space_args.space_slots == 0) {
2966 space_args.total_spaces = slot_count;
2967 goto out;
2968 }
2969
2970 slot_count = min_t(u64, space_args.space_slots, slot_count);
2971
2972 alloc_size = sizeof(*dest) * slot_count;
2973
2974 /* we generally have at most 6 or so space infos, one for each raid
2975 * level. So, a whole page should be more than enough for everyone
2976 */
2977 if (alloc_size > PAGE_CACHE_SIZE)
2978 return -ENOMEM;
2979
2980 space_args.total_spaces = 0;
2981 dest = kmalloc(alloc_size, GFP_NOFS);
2982 if (!dest)
2983 return -ENOMEM;
2984 dest_orig = dest;
2985
2986 /* now we have a buffer to copy into */
2987 for (i = 0; i < num_types; i++) {
2988 struct btrfs_space_info *tmp;
2989
2990 if (!slot_count)
2991 break;
2992
2993 info = NULL;
2994 rcu_read_lock();
2995 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2996 list) {
2997 if (tmp->flags == types[i]) {
2998 info = tmp;
2999 break;
3000 }
3001 }
3002 rcu_read_unlock();
3003
3004 if (!info)
3005 continue;
3006 down_read(&info->groups_sem);
3007 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3008 if (!list_empty(&info->block_groups[c])) {
3009 btrfs_get_block_group_info(
3010 &info->block_groups[c], &space);
3011 memcpy(dest, &space, sizeof(space));
3012 dest++;
3013 space_args.total_spaces++;
3014 slot_count--;
3015 }
3016 if (!slot_count)
3017 break;
3018 }
3019 up_read(&info->groups_sem);
3020 }
3021
3022 user_dest = (struct btrfs_ioctl_space_info __user *)
3023 (arg + sizeof(struct btrfs_ioctl_space_args));
3024
3025 if (copy_to_user(user_dest, dest_orig, alloc_size))
3026 ret = -EFAULT;
3027
3028 kfree(dest_orig);
3029 out:
3030 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
3031 ret = -EFAULT;
3032
3033 return ret;
3034 }
3035
3036 /*
3037 * there are many ways the trans_start and trans_end ioctls can lead
3038 * to deadlocks. They should only be used by applications that
3039 * basically own the machine, and have a very in depth understanding
3040 * of all the possible deadlocks and enospc problems.
3041 */
3042 long btrfs_ioctl_trans_end(struct file *file)
3043 {
3044 struct inode *inode = fdentry(file)->d_inode;
3045 struct btrfs_root *root = BTRFS_I(inode)->root;
3046 struct btrfs_trans_handle *trans;
3047
3048 trans = file->private_data;
3049 if (!trans)
3050 return -EINVAL;
3051 file->private_data = NULL;
3052
3053 btrfs_end_transaction(trans, root);
3054
3055 atomic_dec(&root->fs_info->open_ioctl_trans);
3056
3057 mnt_drop_write_file(file);
3058 return 0;
3059 }
3060
3061 static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
3062 {
3063 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
3064 struct btrfs_trans_handle *trans;
3065 u64 transid;
3066 int ret;
3067
3068 trans = btrfs_start_transaction(root, 0);
3069 if (IS_ERR(trans))
3070 return PTR_ERR(trans);
3071 transid = trans->transid;
3072 ret = btrfs_commit_transaction_async(trans, root, 0);
3073 if (ret) {
3074 btrfs_end_transaction(trans, root);
3075 return ret;
3076 }
3077
3078 if (argp)
3079 if (copy_to_user(argp, &transid, sizeof(transid)))
3080 return -EFAULT;
3081 return 0;
3082 }
3083
3084 static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
3085 {
3086 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
3087 u64 transid;
3088
3089 if (argp) {
3090 if (copy_from_user(&transid, argp, sizeof(transid)))
3091 return -EFAULT;
3092 } else {
3093 transid = 0; /* current trans */
3094 }
3095 return btrfs_wait_for_commit(root, transid);
3096 }
3097
3098 static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg)
3099 {
3100 int ret;
3101 struct btrfs_ioctl_scrub_args *sa;
3102
3103 if (!capable(CAP_SYS_ADMIN))
3104 return -EPERM;
3105
3106 sa = memdup_user(arg, sizeof(*sa));
3107 if (IS_ERR(sa))
3108 return PTR_ERR(sa);
3109
3110 ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
3111 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
3112 0);
3113
3114 if (copy_to_user(arg, sa, sizeof(*sa)))
3115 ret = -EFAULT;
3116
3117 kfree(sa);
3118 return ret;
3119 }
3120
3121 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
3122 {
3123 if (!capable(CAP_SYS_ADMIN))
3124 return -EPERM;
3125
3126 return btrfs_scrub_cancel(root->fs_info);
3127 }
3128
3129 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
3130 void __user *arg)
3131 {
3132 struct btrfs_ioctl_scrub_args *sa;
3133 int ret;
3134
3135 if (!capable(CAP_SYS_ADMIN))
3136 return -EPERM;
3137
3138 sa = memdup_user(arg, sizeof(*sa));
3139 if (IS_ERR(sa))
3140 return PTR_ERR(sa);
3141
3142 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
3143
3144 if (copy_to_user(arg, sa, sizeof(*sa)))
3145 ret = -EFAULT;
3146
3147 kfree(sa);
3148 return ret;
3149 }
3150
3151 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
3152 void __user *arg)
3153 {
3154 struct btrfs_ioctl_get_dev_stats *sa;
3155 int ret;
3156
3157 sa = memdup_user(arg, sizeof(*sa));
3158 if (IS_ERR(sa))
3159 return PTR_ERR(sa);
3160
3161 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3162 kfree(sa);
3163 return -EPERM;
3164 }
3165
3166 ret = btrfs_get_dev_stats(root, sa);
3167
3168 if (copy_to_user(arg, sa, sizeof(*sa)))
3169 ret = -EFAULT;
3170
3171 kfree(sa);
3172 return ret;
3173 }
3174
3175 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
3176 {
3177 struct btrfs_ioctl_dev_replace_args *p;
3178 int ret;
3179
3180 if (!capable(CAP_SYS_ADMIN))
3181 return -EPERM;
3182
3183 p = memdup_user(arg, sizeof(*p));
3184 if (IS_ERR(p))
3185 return PTR_ERR(p);
3186
3187 switch (p->cmd) {
3188 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3189 if (atomic_xchg(
3190 &root->fs_info->mutually_exclusive_operation_running,
3191 1)) {
3192 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
3193 ret = -EINPROGRESS;
3194 } else {
3195 ret = btrfs_dev_replace_start(root, p);
3196 atomic_set(
3197 &root->fs_info->mutually_exclusive_operation_running,
3198 0);
3199 }
3200 break;
3201 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
3202 btrfs_dev_replace_status(root->fs_info, p);
3203 ret = 0;
3204 break;
3205 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
3206 ret = btrfs_dev_replace_cancel(root->fs_info, p);
3207 break;
3208 default:
3209 ret = -EINVAL;
3210 break;
3211 }
3212
3213 if (copy_to_user(arg, p, sizeof(*p)))
3214 ret = -EFAULT;
3215
3216 kfree(p);
3217 return ret;
3218 }
3219
3220 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3221 {
3222 int ret = 0;
3223 int i;
3224 u64 rel_ptr;
3225 int size;
3226 struct btrfs_ioctl_ino_path_args *ipa = NULL;
3227 struct inode_fs_paths *ipath = NULL;
3228 struct btrfs_path *path;
3229
3230 if (!capable(CAP_SYS_ADMIN))
3231 return -EPERM;
3232
3233 path = btrfs_alloc_path();
3234 if (!path) {
3235 ret = -ENOMEM;
3236 goto out;
3237 }
3238
3239 ipa = memdup_user(arg, sizeof(*ipa));
3240 if (IS_ERR(ipa)) {
3241 ret = PTR_ERR(ipa);
3242 ipa = NULL;
3243 goto out;
3244 }
3245
3246 size = min_t(u32, ipa->size, 4096);
3247 ipath = init_ipath(size, root, path);
3248 if (IS_ERR(ipath)) {
3249 ret = PTR_ERR(ipath);
3250 ipath = NULL;
3251 goto out;
3252 }
3253
3254 ret = paths_from_inode(ipa->inum, ipath);
3255 if (ret < 0)
3256 goto out;
3257
3258 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3259 rel_ptr = ipath->fspath->val[i] -
3260 (u64)(unsigned long)ipath->fspath->val;
3261 ipath->fspath->val[i] = rel_ptr;
3262 }
3263
3264 ret = copy_to_user((void *)(unsigned long)ipa->fspath,
3265 (void *)(unsigned long)ipath->fspath, size);
3266 if (ret) {
3267 ret = -EFAULT;
3268 goto out;
3269 }
3270
3271 out:
3272 btrfs_free_path(path);
3273 free_ipath(ipath);
3274 kfree(ipa);
3275
3276 return ret;
3277 }
3278
3279 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3280 {
3281 struct btrfs_data_container *inodes = ctx;
3282 const size_t c = 3 * sizeof(u64);
3283
3284 if (inodes->bytes_left >= c) {
3285 inodes->bytes_left -= c;
3286 inodes->val[inodes->elem_cnt] = inum;
3287 inodes->val[inodes->elem_cnt + 1] = offset;
3288 inodes->val[inodes->elem_cnt + 2] = root;
3289 inodes->elem_cnt += 3;
3290 } else {
3291 inodes->bytes_missing += c - inodes->bytes_left;
3292 inodes->bytes_left = 0;
3293 inodes->elem_missed += 3;
3294 }
3295
3296 return 0;
3297 }
3298
3299 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
3300 void __user *arg)
3301 {
3302 int ret = 0;
3303 int size;
3304 struct btrfs_ioctl_logical_ino_args *loi;
3305 struct btrfs_data_container *inodes = NULL;
3306 struct btrfs_path *path = NULL;
3307
3308 if (!capable(CAP_SYS_ADMIN))
3309 return -EPERM;
3310
3311 loi = memdup_user(arg, sizeof(*loi));
3312 if (IS_ERR(loi)) {
3313 ret = PTR_ERR(loi);
3314 loi = NULL;
3315 goto out;
3316 }
3317
3318 path = btrfs_alloc_path();
3319 if (!path) {
3320 ret = -ENOMEM;
3321 goto out;
3322 }
3323
3324 size = min_t(u32, loi->size, 64 * 1024);
3325 inodes = init_data_container(size);
3326 if (IS_ERR(inodes)) {
3327 ret = PTR_ERR(inodes);
3328 inodes = NULL;
3329 goto out;
3330 }
3331
3332 ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
3333 build_ino_list, inodes);
3334 if (ret == -EINVAL)
3335 ret = -ENOENT;
3336 if (ret < 0)
3337 goto out;
3338
3339 ret = copy_to_user((void *)(unsigned long)loi->inodes,
3340 (void *)(unsigned long)inodes, size);
3341 if (ret)
3342 ret = -EFAULT;
3343
3344 out:
3345 btrfs_free_path(path);
3346 vfree(inodes);
3347 kfree(loi);
3348
3349 return ret;
3350 }
3351
3352 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
3353 struct btrfs_ioctl_balance_args *bargs)
3354 {
3355 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3356
3357 bargs->flags = bctl->flags;
3358
3359 if (atomic_read(&fs_info->balance_running))
3360 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3361 if (atomic_read(&fs_info->balance_pause_req))
3362 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3363 if (atomic_read(&fs_info->balance_cancel_req))
3364 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3365
3366 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3367 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3368 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3369
3370 if (lock) {
3371 spin_lock(&fs_info->balance_lock);
3372 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3373 spin_unlock(&fs_info->balance_lock);
3374 } else {
3375 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3376 }
3377 }
3378
3379 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
3380 {
3381 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3382 struct btrfs_fs_info *fs_info = root->fs_info;
3383 struct btrfs_ioctl_balance_args *bargs;
3384 struct btrfs_balance_control *bctl;
3385 int ret;
3386 int need_to_clear_lock = 0;
3387
3388 if (!capable(CAP_SYS_ADMIN))
3389 return -EPERM;
3390
3391 ret = mnt_want_write_file(file);
3392 if (ret)
3393 return ret;
3394
3395 mutex_lock(&fs_info->volume_mutex);
3396 mutex_lock(&fs_info->balance_mutex);
3397
3398 if (arg) {
3399 bargs = memdup_user(arg, sizeof(*bargs));
3400 if (IS_ERR(bargs)) {
3401 ret = PTR_ERR(bargs);
3402 goto out;
3403 }
3404
3405 if (bargs->flags & BTRFS_BALANCE_RESUME) {
3406 if (!fs_info->balance_ctl) {
3407 ret = -ENOTCONN;
3408 goto out_bargs;
3409 }
3410
3411 bctl = fs_info->balance_ctl;
3412 spin_lock(&fs_info->balance_lock);
3413 bctl->flags |= BTRFS_BALANCE_RESUME;
3414 spin_unlock(&fs_info->balance_lock);
3415
3416 goto do_balance;
3417 }
3418 } else {
3419 bargs = NULL;
3420 }
3421
3422 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
3423 1)) {
3424 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
3425 ret = -EINPROGRESS;
3426 goto out_bargs;
3427 }
3428 need_to_clear_lock = 1;
3429
3430 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3431 if (!bctl) {
3432 ret = -ENOMEM;
3433 goto out_bargs;
3434 }
3435
3436 bctl->fs_info = fs_info;
3437 if (arg) {
3438 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
3439 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
3440 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
3441
3442 bctl->flags = bargs->flags;
3443 } else {
3444 /* balance everything - no filters */
3445 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
3446 }
3447
3448 do_balance:
3449 ret = btrfs_balance(bctl, bargs);
3450 /*
3451 * bctl is freed in __cancel_balance or in free_fs_info if
3452 * restriper was paused all the way until unmount
3453 */
3454 if (arg) {
3455 if (copy_to_user(arg, bargs, sizeof(*bargs)))
3456 ret = -EFAULT;
3457 }
3458
3459 out_bargs:
3460 kfree(bargs);
3461 out:
3462 if (need_to_clear_lock)
3463 atomic_set(&root->fs_info->mutually_exclusive_operation_running,
3464 0);
3465 mutex_unlock(&fs_info->balance_mutex);
3466 mutex_unlock(&fs_info->volume_mutex);
3467 mnt_drop_write_file(file);
3468 return ret;
3469 }
3470
3471 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
3472 {
3473 if (!capable(CAP_SYS_ADMIN))
3474 return -EPERM;
3475
3476 switch (cmd) {
3477 case BTRFS_BALANCE_CTL_PAUSE:
3478 return btrfs_pause_balance(root->fs_info);
3479 case BTRFS_BALANCE_CTL_CANCEL:
3480 return btrfs_cancel_balance(root->fs_info);
3481 }
3482
3483 return -EINVAL;
3484 }
3485
3486 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
3487 void __user *arg)
3488 {
3489 struct btrfs_fs_info *fs_info = root->fs_info;
3490 struct btrfs_ioctl_balance_args *bargs;
3491 int ret = 0;
3492
3493 if (!capable(CAP_SYS_ADMIN))
3494 return -EPERM;
3495
3496 mutex_lock(&fs_info->balance_mutex);
3497 if (!fs_info->balance_ctl) {
3498 ret = -ENOTCONN;
3499 goto out;
3500 }
3501
3502 bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
3503 if (!bargs) {
3504 ret = -ENOMEM;
3505 goto out;
3506 }
3507
3508 update_ioctl_balance_args(fs_info, 1, bargs);
3509
3510 if (copy_to_user(arg, bargs, sizeof(*bargs)))
3511 ret = -EFAULT;
3512
3513 kfree(bargs);
3514 out:
3515 mutex_unlock(&fs_info->balance_mutex);
3516 return ret;
3517 }
3518
3519 static long btrfs_ioctl_quota_ctl(struct btrfs_root *root, void __user *arg)
3520 {
3521 struct btrfs_ioctl_quota_ctl_args *sa;
3522 struct btrfs_trans_handle *trans = NULL;
3523 int ret;
3524 int err;
3525
3526 if (!capable(CAP_SYS_ADMIN))
3527 return -EPERM;
3528
3529 if (root->fs_info->sb->s_flags & MS_RDONLY)
3530 return -EROFS;
3531
3532 sa = memdup_user(arg, sizeof(*sa));
3533 if (IS_ERR(sa))
3534 return PTR_ERR(sa);
3535
3536 if (sa->cmd != BTRFS_QUOTA_CTL_RESCAN) {
3537 trans = btrfs_start_transaction(root, 2);
3538 if (IS_ERR(trans)) {
3539 ret = PTR_ERR(trans);
3540 goto out;
3541 }
3542 }
3543
3544 switch (sa->cmd) {
3545 case BTRFS_QUOTA_CTL_ENABLE:
3546 ret = btrfs_quota_enable(trans, root->fs_info);
3547 break;
3548 case BTRFS_QUOTA_CTL_DISABLE:
3549 ret = btrfs_quota_disable(trans, root->fs_info);
3550 break;
3551 case BTRFS_QUOTA_CTL_RESCAN:
3552 ret = btrfs_quota_rescan(root->fs_info);
3553 break;
3554 default:
3555 ret = -EINVAL;
3556 break;
3557 }
3558
3559 if (copy_to_user(arg, sa, sizeof(*sa)))
3560 ret = -EFAULT;
3561
3562 if (trans) {
3563 err = btrfs_commit_transaction(trans, root);
3564 if (err && !ret)
3565 ret = err;
3566 }
3567
3568 out:
3569 kfree(sa);
3570 return ret;
3571 }
3572
3573 static long btrfs_ioctl_qgroup_assign(struct btrfs_root *root, void __user *arg)
3574 {
3575 struct btrfs_ioctl_qgroup_assign_args *sa;
3576 struct btrfs_trans_handle *trans;
3577 int ret;
3578 int err;
3579
3580 if (!capable(CAP_SYS_ADMIN))
3581 return -EPERM;
3582
3583 if (root->fs_info->sb->s_flags & MS_RDONLY)
3584 return -EROFS;
3585
3586 sa = memdup_user(arg, sizeof(*sa));
3587 if (IS_ERR(sa))
3588 return PTR_ERR(sa);
3589
3590 trans = btrfs_join_transaction(root);
3591 if (IS_ERR(trans)) {
3592 ret = PTR_ERR(trans);
3593 goto out;
3594 }
3595
3596 /* FIXME: check if the IDs really exist */
3597 if (sa->assign) {
3598 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
3599 sa->src, sa->dst);
3600 } else {
3601 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
3602 sa->src, sa->dst);
3603 }
3604
3605 err = btrfs_end_transaction(trans, root);
3606 if (err && !ret)
3607 ret = err;
3608
3609 out:
3610 kfree(sa);
3611 return ret;
3612 }
3613
3614 static long btrfs_ioctl_qgroup_create(struct btrfs_root *root, void __user *arg)
3615 {
3616 struct btrfs_ioctl_qgroup_create_args *sa;
3617 struct btrfs_trans_handle *trans;
3618 int ret;
3619 int err;
3620
3621 if (!capable(CAP_SYS_ADMIN))
3622 return -EPERM;
3623
3624 if (root->fs_info->sb->s_flags & MS_RDONLY)
3625 return -EROFS;
3626
3627 sa = memdup_user(arg, sizeof(*sa));
3628 if (IS_ERR(sa))
3629 return PTR_ERR(sa);
3630
3631 trans = btrfs_join_transaction(root);
3632 if (IS_ERR(trans)) {
3633 ret = PTR_ERR(trans);
3634 goto out;
3635 }
3636
3637 /* FIXME: check if the IDs really exist */
3638 if (sa->create) {
3639 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
3640 NULL);
3641 } else {
3642 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
3643 }
3644
3645 err = btrfs_end_transaction(trans, root);
3646 if (err && !ret)
3647 ret = err;
3648
3649 out:
3650 kfree(sa);
3651 return ret;
3652 }
3653
3654 static long btrfs_ioctl_qgroup_limit(struct btrfs_root *root, void __user *arg)
3655 {
3656 struct btrfs_ioctl_qgroup_limit_args *sa;
3657 struct btrfs_trans_handle *trans;
3658 int ret;
3659 int err;
3660 u64 qgroupid;
3661
3662 if (!capable(CAP_SYS_ADMIN))
3663 return -EPERM;
3664
3665 if (root->fs_info->sb->s_flags & MS_RDONLY)
3666 return -EROFS;
3667
3668 sa = memdup_user(arg, sizeof(*sa));
3669 if (IS_ERR(sa))
3670 return PTR_ERR(sa);
3671
3672 trans = btrfs_join_transaction(root);
3673 if (IS_ERR(trans)) {
3674 ret = PTR_ERR(trans);
3675 goto out;
3676 }
3677
3678 qgroupid = sa->qgroupid;
3679 if (!qgroupid) {
3680 /* take the current subvol as qgroup */
3681 qgroupid = root->root_key.objectid;
3682 }
3683
3684 /* FIXME: check if the IDs really exist */
3685 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
3686
3687 err = btrfs_end_transaction(trans, root);
3688 if (err && !ret)
3689 ret = err;
3690
3691 out:
3692 kfree(sa);
3693 return ret;
3694 }
3695
3696 static long btrfs_ioctl_set_received_subvol(struct file *file,
3697 void __user *arg)
3698 {
3699 struct btrfs_ioctl_received_subvol_args *sa = NULL;
3700 struct inode *inode = fdentry(file)->d_inode;
3701 struct btrfs_root *root = BTRFS_I(inode)->root;
3702 struct btrfs_root_item *root_item = &root->root_item;
3703 struct btrfs_trans_handle *trans;
3704 struct timespec ct = CURRENT_TIME;
3705 int ret = 0;
3706
3707 ret = mnt_want_write_file(file);
3708 if (ret < 0)
3709 return ret;
3710
3711 down_write(&root->fs_info->subvol_sem);
3712
3713 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
3714 ret = -EINVAL;
3715 goto out;
3716 }
3717
3718 if (btrfs_root_readonly(root)) {
3719 ret = -EROFS;
3720 goto out;
3721 }
3722
3723 if (!inode_owner_or_capable(inode)) {
3724 ret = -EACCES;
3725 goto out;
3726 }
3727
3728 sa = memdup_user(arg, sizeof(*sa));
3729 if (IS_ERR(sa)) {
3730 ret = PTR_ERR(sa);
3731 sa = NULL;
3732 goto out;
3733 }
3734
3735 trans = btrfs_start_transaction(root, 1);
3736 if (IS_ERR(trans)) {
3737 ret = PTR_ERR(trans);
3738 trans = NULL;
3739 goto out;
3740 }
3741
3742 sa->rtransid = trans->transid;
3743 sa->rtime.sec = ct.tv_sec;
3744 sa->rtime.nsec = ct.tv_nsec;
3745
3746 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
3747 btrfs_set_root_stransid(root_item, sa->stransid);
3748 btrfs_set_root_rtransid(root_item, sa->rtransid);
3749 root_item->stime.sec = cpu_to_le64(sa->stime.sec);
3750 root_item->stime.nsec = cpu_to_le32(sa->stime.nsec);
3751 root_item->rtime.sec = cpu_to_le64(sa->rtime.sec);
3752 root_item->rtime.nsec = cpu_to_le32(sa->rtime.nsec);
3753
3754 ret = btrfs_update_root(trans, root->fs_info->tree_root,
3755 &root->root_key, &root->root_item);
3756 if (ret < 0) {
3757 btrfs_end_transaction(trans, root);
3758 trans = NULL;
3759 goto out;
3760 } else {
3761 ret = btrfs_commit_transaction(trans, root);
3762 if (ret < 0)
3763 goto out;
3764 }
3765
3766 ret = copy_to_user(arg, sa, sizeof(*sa));
3767 if (ret)
3768 ret = -EFAULT;
3769
3770 out:
3771 kfree(sa);
3772 up_write(&root->fs_info->subvol_sem);
3773 mnt_drop_write_file(file);
3774 return ret;
3775 }
3776
3777 long btrfs_ioctl(struct file *file, unsigned int
3778 cmd, unsigned long arg)
3779 {
3780 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3781 void __user *argp = (void __user *)arg;
3782
3783 switch (cmd) {
3784 case FS_IOC_GETFLAGS:
3785 return btrfs_ioctl_getflags(file, argp);
3786 case FS_IOC_SETFLAGS:
3787 return btrfs_ioctl_setflags(file, argp);
3788 case FS_IOC_GETVERSION:
3789 return btrfs_ioctl_getversion(file, argp);
3790 case FITRIM:
3791 return btrfs_ioctl_fitrim(file, argp);
3792 case BTRFS_IOC_SNAP_CREATE:
3793 return btrfs_ioctl_snap_create(file, argp, 0);
3794 case BTRFS_IOC_SNAP_CREATE_V2:
3795 return btrfs_ioctl_snap_create_v2(file, argp, 0);
3796 case BTRFS_IOC_SUBVOL_CREATE:
3797 return btrfs_ioctl_snap_create(file, argp, 1);
3798 case BTRFS_IOC_SUBVOL_CREATE_V2:
3799 return btrfs_ioctl_snap_create_v2(file, argp, 1);
3800 case BTRFS_IOC_SNAP_DESTROY:
3801 return btrfs_ioctl_snap_destroy(file, argp);
3802 case BTRFS_IOC_SUBVOL_GETFLAGS:
3803 return btrfs_ioctl_subvol_getflags(file, argp);
3804 case BTRFS_IOC_SUBVOL_SETFLAGS:
3805 return btrfs_ioctl_subvol_setflags(file, argp);
3806 case BTRFS_IOC_DEFAULT_SUBVOL:
3807 return btrfs_ioctl_default_subvol(file, argp);
3808 case BTRFS_IOC_DEFRAG:
3809 return btrfs_ioctl_defrag(file, NULL);
3810 case BTRFS_IOC_DEFRAG_RANGE:
3811 return btrfs_ioctl_defrag(file, argp);
3812 case BTRFS_IOC_RESIZE:
3813 return btrfs_ioctl_resize(root, argp);
3814 case BTRFS_IOC_ADD_DEV:
3815 return btrfs_ioctl_add_dev(root, argp);
3816 case BTRFS_IOC_RM_DEV:
3817 return btrfs_ioctl_rm_dev(root, argp);
3818 case BTRFS_IOC_FS_INFO:
3819 return btrfs_ioctl_fs_info(root, argp);
3820 case BTRFS_IOC_DEV_INFO:
3821 return btrfs_ioctl_dev_info(root, argp);
3822 case BTRFS_IOC_BALANCE:
3823 return btrfs_ioctl_balance(file, NULL);
3824 case BTRFS_IOC_CLONE:
3825 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
3826 case BTRFS_IOC_CLONE_RANGE:
3827 return btrfs_ioctl_clone_range(file, argp);
3828 case BTRFS_IOC_TRANS_START:
3829 return btrfs_ioctl_trans_start(file);
3830 case BTRFS_IOC_TRANS_END:
3831 return btrfs_ioctl_trans_end(file);
3832 case BTRFS_IOC_TREE_SEARCH:
3833 return btrfs_ioctl_tree_search(file, argp);
3834 case BTRFS_IOC_INO_LOOKUP:
3835 return btrfs_ioctl_ino_lookup(file, argp);
3836 case BTRFS_IOC_INO_PATHS:
3837 return btrfs_ioctl_ino_to_path(root, argp);
3838 case BTRFS_IOC_LOGICAL_INO:
3839 return btrfs_ioctl_logical_to_ino(root, argp);
3840 case BTRFS_IOC_SPACE_INFO:
3841 return btrfs_ioctl_space_info(root, argp);
3842 case BTRFS_IOC_SYNC:
3843 btrfs_sync_fs(file->f_dentry->d_sb, 1);
3844 return 0;
3845 case BTRFS_IOC_START_SYNC:
3846 return btrfs_ioctl_start_sync(file, argp);
3847 case BTRFS_IOC_WAIT_SYNC:
3848 return btrfs_ioctl_wait_sync(file, argp);
3849 case BTRFS_IOC_SCRUB:
3850 return btrfs_ioctl_scrub(root, argp);
3851 case BTRFS_IOC_SCRUB_CANCEL:
3852 return btrfs_ioctl_scrub_cancel(root, argp);
3853 case BTRFS_IOC_SCRUB_PROGRESS:
3854 return btrfs_ioctl_scrub_progress(root, argp);
3855 case BTRFS_IOC_BALANCE_V2:
3856 return btrfs_ioctl_balance(file, argp);
3857 case BTRFS_IOC_BALANCE_CTL:
3858 return btrfs_ioctl_balance_ctl(root, arg);
3859 case BTRFS_IOC_BALANCE_PROGRESS:
3860 return btrfs_ioctl_balance_progress(root, argp);
3861 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
3862 return btrfs_ioctl_set_received_subvol(file, argp);
3863 case BTRFS_IOC_SEND:
3864 return btrfs_ioctl_send(file, argp);
3865 case BTRFS_IOC_GET_DEV_STATS:
3866 return btrfs_ioctl_get_dev_stats(root, argp);
3867 case BTRFS_IOC_QUOTA_CTL:
3868 return btrfs_ioctl_quota_ctl(root, argp);
3869 case BTRFS_IOC_QGROUP_ASSIGN:
3870 return btrfs_ioctl_qgroup_assign(root, argp);
3871 case BTRFS_IOC_QGROUP_CREATE:
3872 return btrfs_ioctl_qgroup_create(root, argp);
3873 case BTRFS_IOC_QGROUP_LIMIT:
3874 return btrfs_ioctl_qgroup_limit(root, argp);
3875 case BTRFS_IOC_DEV_REPLACE:
3876 return btrfs_ioctl_dev_replace(root, argp);
3877 }
3878
3879 return -ENOTTY;
3880 }
Linux kernel - Deliverables
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