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Btrfs: fix __btrfs_map_block on 32 bit machines
[mirror_ubuntu-bionic-kernel.git] / fs / btrfs / ioctl.c
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19 #include <linux/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.h>
23 #include <linux/fs.h>
24 #include <linux/fsnotify.h>
25 #include <linux/pagemap.h>
26 #include <linux/highmem.h>
27 #include <linux/time.h>
28 #include <linux/init.h>
29 #include <linux/string.h>
30 #include <linux/backing-dev.h>
31 #include <linux/mount.h>
32 #include <linux/mpage.h>
33 #include <linux/namei.h>
34 #include <linux/swap.h>
35 #include <linux/writeback.h>
36 #include <linux/statfs.h>
37 #include <linux/compat.h>
38 #include <linux/bit_spinlock.h>
39 #include <linux/security.h>
40 #include <linux/xattr.h>
41 #include <linux/vmalloc.h>
42 #include <linux/slab.h>
43 #include <linux/blkdev.h>
44 #include "compat.h"
45 #include "ctree.h"
46 #include "disk-io.h"
47 #include "transaction.h"
48 #include "btrfs_inode.h"
49 #include "ioctl.h"
50 #include "print-tree.h"
51 #include "volumes.h"
52 #include "locking.h"
53
54 /* Mask out flags that are inappropriate for the given type of inode. */
55 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
56 {
57 if (S_ISDIR(mode))
58 return flags;
59 else if (S_ISREG(mode))
60 return flags & ~FS_DIRSYNC_FL;
61 else
62 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
63 }
64
65 /*
66 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
67 */
68 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
69 {
70 unsigned int iflags = 0;
71
72 if (flags & BTRFS_INODE_SYNC)
73 iflags |= FS_SYNC_FL;
74 if (flags & BTRFS_INODE_IMMUTABLE)
75 iflags |= FS_IMMUTABLE_FL;
76 if (flags & BTRFS_INODE_APPEND)
77 iflags |= FS_APPEND_FL;
78 if (flags & BTRFS_INODE_NODUMP)
79 iflags |= FS_NODUMP_FL;
80 if (flags & BTRFS_INODE_NOATIME)
81 iflags |= FS_NOATIME_FL;
82 if (flags & BTRFS_INODE_DIRSYNC)
83 iflags |= FS_DIRSYNC_FL;
84
85 return iflags;
86 }
87
88 /*
89 * Update inode->i_flags based on the btrfs internal flags.
90 */
91 void btrfs_update_iflags(struct inode *inode)
92 {
93 struct btrfs_inode *ip = BTRFS_I(inode);
94
95 inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
96
97 if (ip->flags & BTRFS_INODE_SYNC)
98 inode->i_flags |= S_SYNC;
99 if (ip->flags & BTRFS_INODE_IMMUTABLE)
100 inode->i_flags |= S_IMMUTABLE;
101 if (ip->flags & BTRFS_INODE_APPEND)
102 inode->i_flags |= S_APPEND;
103 if (ip->flags & BTRFS_INODE_NOATIME)
104 inode->i_flags |= S_NOATIME;
105 if (ip->flags & BTRFS_INODE_DIRSYNC)
106 inode->i_flags |= S_DIRSYNC;
107 }
108
109 /*
110 * Inherit flags from the parent inode.
111 *
112 * Unlike extN we don't have any flags we don't want to inherit currently.
113 */
114 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
115 {
116 unsigned int flags;
117
118 if (!dir)
119 return;
120
121 flags = BTRFS_I(dir)->flags;
122
123 if (S_ISREG(inode->i_mode))
124 flags &= ~BTRFS_INODE_DIRSYNC;
125 else if (!S_ISDIR(inode->i_mode))
126 flags &= (BTRFS_INODE_NODUMP | BTRFS_INODE_NOATIME);
127
128 BTRFS_I(inode)->flags = flags;
129 btrfs_update_iflags(inode);
130 }
131
132 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
133 {
134 struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
135 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
136
137 if (copy_to_user(arg, &flags, sizeof(flags)))
138 return -EFAULT;
139 return 0;
140 }
141
142 static int check_flags(unsigned int flags)
143 {
144 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
145 FS_NOATIME_FL | FS_NODUMP_FL | \
146 FS_SYNC_FL | FS_DIRSYNC_FL | \
147 FS_NOCOMP_FL | FS_COMPR_FL | \
148 FS_NOCOW_FL | FS_COW_FL))
149 return -EOPNOTSUPP;
150
151 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
152 return -EINVAL;
153
154 if ((flags & FS_NOCOW_FL) && (flags & FS_COW_FL))
155 return -EINVAL;
156
157 return 0;
158 }
159
160 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
161 {
162 struct inode *inode = file->f_path.dentry->d_inode;
163 struct btrfs_inode *ip = BTRFS_I(inode);
164 struct btrfs_root *root = ip->root;
165 struct btrfs_trans_handle *trans;
166 unsigned int flags, oldflags;
167 int ret;
168
169 if (btrfs_root_readonly(root))
170 return -EROFS;
171
172 if (copy_from_user(&flags, arg, sizeof(flags)))
173 return -EFAULT;
174
175 ret = check_flags(flags);
176 if (ret)
177 return ret;
178
179 if (!is_owner_or_cap(inode))
180 return -EACCES;
181
182 mutex_lock(&inode->i_mutex);
183
184 flags = btrfs_mask_flags(inode->i_mode, flags);
185 oldflags = btrfs_flags_to_ioctl(ip->flags);
186 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
187 if (!capable(CAP_LINUX_IMMUTABLE)) {
188 ret = -EPERM;
189 goto out_unlock;
190 }
191 }
192
193 ret = mnt_want_write(file->f_path.mnt);
194 if (ret)
195 goto out_unlock;
196
197 if (flags & FS_SYNC_FL)
198 ip->flags |= BTRFS_INODE_SYNC;
199 else
200 ip->flags &= ~BTRFS_INODE_SYNC;
201 if (flags & FS_IMMUTABLE_FL)
202 ip->flags |= BTRFS_INODE_IMMUTABLE;
203 else
204 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
205 if (flags & FS_APPEND_FL)
206 ip->flags |= BTRFS_INODE_APPEND;
207 else
208 ip->flags &= ~BTRFS_INODE_APPEND;
209 if (flags & FS_NODUMP_FL)
210 ip->flags |= BTRFS_INODE_NODUMP;
211 else
212 ip->flags &= ~BTRFS_INODE_NODUMP;
213 if (flags & FS_NOATIME_FL)
214 ip->flags |= BTRFS_INODE_NOATIME;
215 else
216 ip->flags &= ~BTRFS_INODE_NOATIME;
217 if (flags & FS_DIRSYNC_FL)
218 ip->flags |= BTRFS_INODE_DIRSYNC;
219 else
220 ip->flags &= ~BTRFS_INODE_DIRSYNC;
221
222 /*
223 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
224 * flag may be changed automatically if compression code won't make
225 * things smaller.
226 */
227 if (flags & FS_NOCOMP_FL) {
228 ip->flags &= ~BTRFS_INODE_COMPRESS;
229 ip->flags |= BTRFS_INODE_NOCOMPRESS;
230 } else if (flags & FS_COMPR_FL) {
231 ip->flags |= BTRFS_INODE_COMPRESS;
232 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
233 }
234 if (flags & FS_NOCOW_FL)
235 ip->flags |= BTRFS_INODE_NODATACOW;
236 else if (flags & FS_COW_FL)
237 ip->flags &= ~BTRFS_INODE_NODATACOW;
238
239 trans = btrfs_join_transaction(root, 1);
240 BUG_ON(IS_ERR(trans));
241
242 ret = btrfs_update_inode(trans, root, inode);
243 BUG_ON(ret);
244
245 btrfs_update_iflags(inode);
246 inode->i_ctime = CURRENT_TIME;
247 btrfs_end_transaction(trans, root);
248
249 mnt_drop_write(file->f_path.mnt);
250
251 ret = 0;
252 out_unlock:
253 mutex_unlock(&inode->i_mutex);
254 return ret;
255 }
256
257 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
258 {
259 struct inode *inode = file->f_path.dentry->d_inode;
260
261 return put_user(inode->i_generation, arg);
262 }
263
264 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
265 {
266 struct btrfs_root *root = fdentry(file)->d_sb->s_fs_info;
267 struct btrfs_fs_info *fs_info = root->fs_info;
268 struct btrfs_device *device;
269 struct request_queue *q;
270 struct fstrim_range range;
271 u64 minlen = ULLONG_MAX;
272 u64 num_devices = 0;
273 int ret;
274
275 if (!capable(CAP_SYS_ADMIN))
276 return -EPERM;
277
278 mutex_lock(&fs_info->fs_devices->device_list_mutex);
279 list_for_each_entry(device, &fs_info->fs_devices->devices, dev_list) {
280 if (!device->bdev)
281 continue;
282 q = bdev_get_queue(device->bdev);
283 if (blk_queue_discard(q)) {
284 num_devices++;
285 minlen = min((u64)q->limits.discard_granularity,
286 minlen);
287 }
288 }
289 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
290 if (!num_devices)
291 return -EOPNOTSUPP;
292
293 if (copy_from_user(&range, arg, sizeof(range)))
294 return -EFAULT;
295
296 range.minlen = max(range.minlen, minlen);
297 ret = btrfs_trim_fs(root, &range);
298 if (ret < 0)
299 return ret;
300
301 if (copy_to_user(arg, &range, sizeof(range)))
302 return -EFAULT;
303
304 return 0;
305 }
306
307 static noinline int create_subvol(struct btrfs_root *root,
308 struct dentry *dentry,
309 char *name, int namelen,
310 u64 *async_transid)
311 {
312 struct btrfs_trans_handle *trans;
313 struct btrfs_key key;
314 struct btrfs_root_item root_item;
315 struct btrfs_inode_item *inode_item;
316 struct extent_buffer *leaf;
317 struct btrfs_root *new_root;
318 struct dentry *parent = dget_parent(dentry);
319 struct inode *dir;
320 int ret;
321 int err;
322 u64 objectid;
323 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
324 u64 index = 0;
325
326 ret = btrfs_find_free_objectid(NULL, root->fs_info->tree_root,
327 0, &objectid);
328 if (ret) {
329 dput(parent);
330 return ret;
331 }
332
333 dir = parent->d_inode;
334
335 /*
336 * 1 - inode item
337 * 2 - refs
338 * 1 - root item
339 * 2 - dir items
340 */
341 trans = btrfs_start_transaction(root, 6);
342 if (IS_ERR(trans)) {
343 dput(parent);
344 return PTR_ERR(trans);
345 }
346
347 leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
348 0, objectid, NULL, 0, 0, 0);
349 if (IS_ERR(leaf)) {
350 ret = PTR_ERR(leaf);
351 goto fail;
352 }
353
354 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
355 btrfs_set_header_bytenr(leaf, leaf->start);
356 btrfs_set_header_generation(leaf, trans->transid);
357 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
358 btrfs_set_header_owner(leaf, objectid);
359
360 write_extent_buffer(leaf, root->fs_info->fsid,
361 (unsigned long)btrfs_header_fsid(leaf),
362 BTRFS_FSID_SIZE);
363 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
364 (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
365 BTRFS_UUID_SIZE);
366 btrfs_mark_buffer_dirty(leaf);
367
368 inode_item = &root_item.inode;
369 memset(inode_item, 0, sizeof(*inode_item));
370 inode_item->generation = cpu_to_le64(1);
371 inode_item->size = cpu_to_le64(3);
372 inode_item->nlink = cpu_to_le32(1);
373 inode_item->nbytes = cpu_to_le64(root->leafsize);
374 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
375
376 btrfs_set_root_bytenr(&root_item, leaf->start);
377 btrfs_set_root_generation(&root_item, trans->transid);
378 btrfs_set_root_level(&root_item, 0);
379 btrfs_set_root_refs(&root_item, 1);
380 btrfs_set_root_used(&root_item, leaf->len);
381 btrfs_set_root_last_snapshot(&root_item, 0);
382
383 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
384 root_item.drop_level = 0;
385
386 btrfs_tree_unlock(leaf);
387 free_extent_buffer(leaf);
388 leaf = NULL;
389
390 btrfs_set_root_dirid(&root_item, new_dirid);
391
392 key.objectid = objectid;
393 key.offset = 0;
394 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
395 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
396 &root_item);
397 if (ret)
398 goto fail;
399
400 key.offset = (u64)-1;
401 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
402 BUG_ON(IS_ERR(new_root));
403
404 btrfs_record_root_in_trans(trans, new_root);
405
406 ret = btrfs_create_subvol_root(trans, new_root, new_dirid,
407 BTRFS_I(dir)->block_group);
408 /*
409 * insert the directory item
410 */
411 ret = btrfs_set_inode_index(dir, &index);
412 BUG_ON(ret);
413
414 ret = btrfs_insert_dir_item(trans, root,
415 name, namelen, dir->i_ino, &key,
416 BTRFS_FT_DIR, index);
417 if (ret)
418 goto fail;
419
420 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
421 ret = btrfs_update_inode(trans, root, dir);
422 BUG_ON(ret);
423
424 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
425 objectid, root->root_key.objectid,
426 dir->i_ino, index, name, namelen);
427
428 BUG_ON(ret);
429
430 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
431 fail:
432 dput(parent);
433 if (async_transid) {
434 *async_transid = trans->transid;
435 err = btrfs_commit_transaction_async(trans, root, 1);
436 } else {
437 err = btrfs_commit_transaction(trans, root);
438 }
439 if (err && !ret)
440 ret = err;
441 return ret;
442 }
443
444 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
445 char *name, int namelen, u64 *async_transid,
446 bool readonly)
447 {
448 struct inode *inode;
449 struct dentry *parent;
450 struct btrfs_pending_snapshot *pending_snapshot;
451 struct btrfs_trans_handle *trans;
452 int ret;
453
454 if (!root->ref_cows)
455 return -EINVAL;
456
457 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
458 if (!pending_snapshot)
459 return -ENOMEM;
460
461 btrfs_init_block_rsv(&pending_snapshot->block_rsv);
462 pending_snapshot->dentry = dentry;
463 pending_snapshot->root = root;
464 pending_snapshot->readonly = readonly;
465
466 trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
467 if (IS_ERR(trans)) {
468 ret = PTR_ERR(trans);
469 goto fail;
470 }
471
472 ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
473 BUG_ON(ret);
474
475 list_add(&pending_snapshot->list,
476 &trans->transaction->pending_snapshots);
477 if (async_transid) {
478 *async_transid = trans->transid;
479 ret = btrfs_commit_transaction_async(trans,
480 root->fs_info->extent_root, 1);
481 } else {
482 ret = btrfs_commit_transaction(trans,
483 root->fs_info->extent_root);
484 }
485 BUG_ON(ret);
486
487 ret = pending_snapshot->error;
488 if (ret)
489 goto fail;
490
491 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
492 if (ret)
493 goto fail;
494
495 parent = dget_parent(dentry);
496 inode = btrfs_lookup_dentry(parent->d_inode, dentry);
497 dput(parent);
498 if (IS_ERR(inode)) {
499 ret = PTR_ERR(inode);
500 goto fail;
501 }
502 BUG_ON(!inode);
503 d_instantiate(dentry, inode);
504 ret = 0;
505 fail:
506 kfree(pending_snapshot);
507 return ret;
508 }
509
510 /* copy of check_sticky in fs/namei.c()
511 * It's inline, so penalty for filesystems that don't use sticky bit is
512 * minimal.
513 */
514 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
515 {
516 uid_t fsuid = current_fsuid();
517
518 if (!(dir->i_mode & S_ISVTX))
519 return 0;
520 if (inode->i_uid == fsuid)
521 return 0;
522 if (dir->i_uid == fsuid)
523 return 0;
524 return !capable(CAP_FOWNER);
525 }
526
527 /* copy of may_delete in fs/namei.c()
528 * Check whether we can remove a link victim from directory dir, check
529 * whether the type of victim is right.
530 * 1. We can't do it if dir is read-only (done in permission())
531 * 2. We should have write and exec permissions on dir
532 * 3. We can't remove anything from append-only dir
533 * 4. We can't do anything with immutable dir (done in permission())
534 * 5. If the sticky bit on dir is set we should either
535 * a. be owner of dir, or
536 * b. be owner of victim, or
537 * c. have CAP_FOWNER capability
538 * 6. If the victim is append-only or immutable we can't do antyhing with
539 * links pointing to it.
540 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
541 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
542 * 9. We can't remove a root or mountpoint.
543 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
544 * nfs_async_unlink().
545 */
546
547 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
548 {
549 int error;
550
551 if (!victim->d_inode)
552 return -ENOENT;
553
554 BUG_ON(victim->d_parent->d_inode != dir);
555 audit_inode_child(victim, dir);
556
557 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
558 if (error)
559 return error;
560 if (IS_APPEND(dir))
561 return -EPERM;
562 if (btrfs_check_sticky(dir, victim->d_inode)||
563 IS_APPEND(victim->d_inode)||
564 IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
565 return -EPERM;
566 if (isdir) {
567 if (!S_ISDIR(victim->d_inode->i_mode))
568 return -ENOTDIR;
569 if (IS_ROOT(victim))
570 return -EBUSY;
571 } else if (S_ISDIR(victim->d_inode->i_mode))
572 return -EISDIR;
573 if (IS_DEADDIR(dir))
574 return -ENOENT;
575 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
576 return -EBUSY;
577 return 0;
578 }
579
580 /* copy of may_create in fs/namei.c() */
581 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
582 {
583 if (child->d_inode)
584 return -EEXIST;
585 if (IS_DEADDIR(dir))
586 return -ENOENT;
587 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
588 }
589
590 /*
591 * Create a new subvolume below @parent. This is largely modeled after
592 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
593 * inside this filesystem so it's quite a bit simpler.
594 */
595 static noinline int btrfs_mksubvol(struct path *parent,
596 char *name, int namelen,
597 struct btrfs_root *snap_src,
598 u64 *async_transid, bool readonly)
599 {
600 struct inode *dir = parent->dentry->d_inode;
601 struct dentry *dentry;
602 int error;
603
604 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
605
606 dentry = lookup_one_len(name, parent->dentry, namelen);
607 error = PTR_ERR(dentry);
608 if (IS_ERR(dentry))
609 goto out_unlock;
610
611 error = -EEXIST;
612 if (dentry->d_inode)
613 goto out_dput;
614
615 error = mnt_want_write(parent->mnt);
616 if (error)
617 goto out_dput;
618
619 error = btrfs_may_create(dir, dentry);
620 if (error)
621 goto out_drop_write;
622
623 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
624
625 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
626 goto out_up_read;
627
628 if (snap_src) {
629 error = create_snapshot(snap_src, dentry,
630 name, namelen, async_transid, readonly);
631 } else {
632 error = create_subvol(BTRFS_I(dir)->root, dentry,
633 name, namelen, async_transid);
634 }
635 if (!error)
636 fsnotify_mkdir(dir, dentry);
637 out_up_read:
638 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
639 out_drop_write:
640 mnt_drop_write(parent->mnt);
641 out_dput:
642 dput(dentry);
643 out_unlock:
644 mutex_unlock(&dir->i_mutex);
645 return error;
646 }
647
648 static int should_defrag_range(struct inode *inode, u64 start, u64 len,
649 int thresh, u64 *last_len, u64 *skip,
650 u64 *defrag_end)
651 {
652 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
653 struct extent_map *em = NULL;
654 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
655 int ret = 1;
656
657
658 if (thresh == 0)
659 thresh = 256 * 1024;
660
661 /*
662 * make sure that once we start defragging and extent, we keep on
663 * defragging it
664 */
665 if (start < *defrag_end)
666 return 1;
667
668 *skip = 0;
669
670 /*
671 * hopefully we have this extent in the tree already, try without
672 * the full extent lock
673 */
674 read_lock(&em_tree->lock);
675 em = lookup_extent_mapping(em_tree, start, len);
676 read_unlock(&em_tree->lock);
677
678 if (!em) {
679 /* get the big lock and read metadata off disk */
680 lock_extent(io_tree, start, start + len - 1, GFP_NOFS);
681 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
682 unlock_extent(io_tree, start, start + len - 1, GFP_NOFS);
683
684 if (IS_ERR(em))
685 return 0;
686 }
687
688 /* this will cover holes, and inline extents */
689 if (em->block_start >= EXTENT_MAP_LAST_BYTE)
690 ret = 0;
691
692 /*
693 * we hit a real extent, if it is big don't bother defragging it again
694 */
695 if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
696 ret = 0;
697
698 /*
699 * last_len ends up being a counter of how many bytes we've defragged.
700 * every time we choose not to defrag an extent, we reset *last_len
701 * so that the next tiny extent will force a defrag.
702 *
703 * The end result of this is that tiny extents before a single big
704 * extent will force at least part of that big extent to be defragged.
705 */
706 if (ret) {
707 *last_len += len;
708 *defrag_end = extent_map_end(em);
709 } else {
710 *last_len = 0;
711 *skip = extent_map_end(em);
712 *defrag_end = 0;
713 }
714
715 free_extent_map(em);
716 return ret;
717 }
718
719 static int btrfs_defrag_file(struct file *file,
720 struct btrfs_ioctl_defrag_range_args *range)
721 {
722 struct inode *inode = fdentry(file)->d_inode;
723 struct btrfs_root *root = BTRFS_I(inode)->root;
724 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
725 struct btrfs_ordered_extent *ordered;
726 struct page *page;
727 struct btrfs_super_block *disk_super;
728 unsigned long last_index;
729 unsigned long ra_pages = root->fs_info->bdi.ra_pages;
730 unsigned long total_read = 0;
731 u64 features;
732 u64 page_start;
733 u64 page_end;
734 u64 last_len = 0;
735 u64 skip = 0;
736 u64 defrag_end = 0;
737 unsigned long i;
738 int ret;
739 int compress_type = BTRFS_COMPRESS_ZLIB;
740
741 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
742 if (range->compress_type > BTRFS_COMPRESS_TYPES)
743 return -EINVAL;
744 if (range->compress_type)
745 compress_type = range->compress_type;
746 }
747
748 if (inode->i_size == 0)
749 return 0;
750
751 if (range->start + range->len > range->start) {
752 last_index = min_t(u64, inode->i_size - 1,
753 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
754 } else {
755 last_index = (inode->i_size - 1) >> PAGE_CACHE_SHIFT;
756 }
757
758 i = range->start >> PAGE_CACHE_SHIFT;
759 while (i <= last_index) {
760 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
761 PAGE_CACHE_SIZE,
762 range->extent_thresh,
763 &last_len, &skip,
764 &defrag_end)) {
765 unsigned long next;
766 /*
767 * the should_defrag function tells us how much to skip
768 * bump our counter by the suggested amount
769 */
770 next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
771 i = max(i + 1, next);
772 continue;
773 }
774
775 if (total_read % ra_pages == 0) {
776 btrfs_force_ra(inode->i_mapping, &file->f_ra, file, i,
777 min(last_index, i + ra_pages - 1));
778 }
779 total_read++;
780 mutex_lock(&inode->i_mutex);
781 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
782 BTRFS_I(inode)->force_compress = compress_type;
783
784 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
785 if (ret)
786 goto err_unlock;
787 again:
788 if (inode->i_size == 0 ||
789 i > ((inode->i_size - 1) >> PAGE_CACHE_SHIFT)) {
790 ret = 0;
791 goto err_reservations;
792 }
793
794 page = grab_cache_page(inode->i_mapping, i);
795 if (!page) {
796 ret = -ENOMEM;
797 goto err_reservations;
798 }
799
800 if (!PageUptodate(page)) {
801 btrfs_readpage(NULL, page);
802 lock_page(page);
803 if (!PageUptodate(page)) {
804 unlock_page(page);
805 page_cache_release(page);
806 ret = -EIO;
807 goto err_reservations;
808 }
809 }
810
811 if (page->mapping != inode->i_mapping) {
812 unlock_page(page);
813 page_cache_release(page);
814 goto again;
815 }
816
817 wait_on_page_writeback(page);
818
819 if (PageDirty(page)) {
820 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
821 goto loop_unlock;
822 }
823
824 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
825 page_end = page_start + PAGE_CACHE_SIZE - 1;
826 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
827
828 ordered = btrfs_lookup_ordered_extent(inode, page_start);
829 if (ordered) {
830 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
831 unlock_page(page);
832 page_cache_release(page);
833 btrfs_start_ordered_extent(inode, ordered, 1);
834 btrfs_put_ordered_extent(ordered);
835 goto again;
836 }
837 set_page_extent_mapped(page);
838
839 /*
840 * this makes sure page_mkwrite is called on the
841 * page if it is dirtied again later
842 */
843 clear_page_dirty_for_io(page);
844 clear_extent_bits(&BTRFS_I(inode)->io_tree, page_start,
845 page_end, EXTENT_DIRTY | EXTENT_DELALLOC |
846 EXTENT_DO_ACCOUNTING, GFP_NOFS);
847
848 btrfs_set_extent_delalloc(inode, page_start, page_end, NULL);
849 ClearPageChecked(page);
850 set_page_dirty(page);
851 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
852
853 loop_unlock:
854 unlock_page(page);
855 page_cache_release(page);
856 mutex_unlock(&inode->i_mutex);
857
858 balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);
859 i++;
860 }
861
862 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
863 filemap_flush(inode->i_mapping);
864
865 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
866 /* the filemap_flush will queue IO into the worker threads, but
867 * we have to make sure the IO is actually started and that
868 * ordered extents get created before we return
869 */
870 atomic_inc(&root->fs_info->async_submit_draining);
871 while (atomic_read(&root->fs_info->nr_async_submits) ||
872 atomic_read(&root->fs_info->async_delalloc_pages)) {
873 wait_event(root->fs_info->async_submit_wait,
874 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
875 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
876 }
877 atomic_dec(&root->fs_info->async_submit_draining);
878
879 mutex_lock(&inode->i_mutex);
880 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
881 mutex_unlock(&inode->i_mutex);
882 }
883
884 disk_super = &root->fs_info->super_copy;
885 features = btrfs_super_incompat_flags(disk_super);
886 if (range->compress_type == BTRFS_COMPRESS_LZO) {
887 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
888 btrfs_set_super_incompat_flags(disk_super, features);
889 }
890
891 return 0;
892
893 err_reservations:
894 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
895 err_unlock:
896 mutex_unlock(&inode->i_mutex);
897 return ret;
898 }
899
900 static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
901 void __user *arg)
902 {
903 u64 new_size;
904 u64 old_size;
905 u64 devid = 1;
906 struct btrfs_ioctl_vol_args *vol_args;
907 struct btrfs_trans_handle *trans;
908 struct btrfs_device *device = NULL;
909 char *sizestr;
910 char *devstr = NULL;
911 int ret = 0;
912 int mod = 0;
913
914 if (root->fs_info->sb->s_flags & MS_RDONLY)
915 return -EROFS;
916
917 if (!capable(CAP_SYS_ADMIN))
918 return -EPERM;
919
920 vol_args = memdup_user(arg, sizeof(*vol_args));
921 if (IS_ERR(vol_args))
922 return PTR_ERR(vol_args);
923
924 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
925
926 mutex_lock(&root->fs_info->volume_mutex);
927 sizestr = vol_args->name;
928 devstr = strchr(sizestr, ':');
929 if (devstr) {
930 char *end;
931 sizestr = devstr + 1;
932 *devstr = '\0';
933 devstr = vol_args->name;
934 devid = simple_strtoull(devstr, &end, 10);
935 printk(KERN_INFO "resizing devid %llu\n",
936 (unsigned long long)devid);
937 }
938 device = btrfs_find_device(root, devid, NULL, NULL);
939 if (!device) {
940 printk(KERN_INFO "resizer unable to find device %llu\n",
941 (unsigned long long)devid);
942 ret = -EINVAL;
943 goto out_unlock;
944 }
945 if (!strcmp(sizestr, "max"))
946 new_size = device->bdev->bd_inode->i_size;
947 else {
948 if (sizestr[0] == '-') {
949 mod = -1;
950 sizestr++;
951 } else if (sizestr[0] == '+') {
952 mod = 1;
953 sizestr++;
954 }
955 new_size = memparse(sizestr, NULL);
956 if (new_size == 0) {
957 ret = -EINVAL;
958 goto out_unlock;
959 }
960 }
961
962 old_size = device->total_bytes;
963
964 if (mod < 0) {
965 if (new_size > old_size) {
966 ret = -EINVAL;
967 goto out_unlock;
968 }
969 new_size = old_size - new_size;
970 } else if (mod > 0) {
971 new_size = old_size + new_size;
972 }
973
974 if (new_size < 256 * 1024 * 1024) {
975 ret = -EINVAL;
976 goto out_unlock;
977 }
978 if (new_size > device->bdev->bd_inode->i_size) {
979 ret = -EFBIG;
980 goto out_unlock;
981 }
982
983 do_div(new_size, root->sectorsize);
984 new_size *= root->sectorsize;
985
986 printk(KERN_INFO "new size for %s is %llu\n",
987 device->name, (unsigned long long)new_size);
988
989 if (new_size > old_size) {
990 trans = btrfs_start_transaction(root, 0);
991 if (IS_ERR(trans)) {
992 ret = PTR_ERR(trans);
993 goto out_unlock;
994 }
995 ret = btrfs_grow_device(trans, device, new_size);
996 btrfs_commit_transaction(trans, root);
997 } else {
998 ret = btrfs_shrink_device(device, new_size);
999 }
1000
1001 out_unlock:
1002 mutex_unlock(&root->fs_info->volume_mutex);
1003 kfree(vol_args);
1004 return ret;
1005 }
1006
1007 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1008 char *name,
1009 unsigned long fd,
1010 int subvol,
1011 u64 *transid,
1012 bool readonly)
1013 {
1014 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1015 struct file *src_file;
1016 int namelen;
1017 int ret = 0;
1018
1019 if (root->fs_info->sb->s_flags & MS_RDONLY)
1020 return -EROFS;
1021
1022 namelen = strlen(name);
1023 if (strchr(name, '/')) {
1024 ret = -EINVAL;
1025 goto out;
1026 }
1027
1028 if (subvol) {
1029 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1030 NULL, transid, readonly);
1031 } else {
1032 struct inode *src_inode;
1033 src_file = fget(fd);
1034 if (!src_file) {
1035 ret = -EINVAL;
1036 goto out;
1037 }
1038
1039 src_inode = src_file->f_path.dentry->d_inode;
1040 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1041 printk(KERN_INFO "btrfs: Snapshot src from "
1042 "another FS\n");
1043 ret = -EINVAL;
1044 fput(src_file);
1045 goto out;
1046 }
1047 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1048 BTRFS_I(src_inode)->root,
1049 transid, readonly);
1050 fput(src_file);
1051 }
1052 out:
1053 return ret;
1054 }
1055
1056 static noinline int btrfs_ioctl_snap_create(struct file *file,
1057 void __user *arg, int subvol)
1058 {
1059 struct btrfs_ioctl_vol_args *vol_args;
1060 int ret;
1061
1062 vol_args = memdup_user(arg, sizeof(*vol_args));
1063 if (IS_ERR(vol_args))
1064 return PTR_ERR(vol_args);
1065 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1066
1067 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1068 vol_args->fd, subvol,
1069 NULL, false);
1070
1071 kfree(vol_args);
1072 return ret;
1073 }
1074
1075 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1076 void __user *arg, int subvol)
1077 {
1078 struct btrfs_ioctl_vol_args_v2 *vol_args;
1079 int ret;
1080 u64 transid = 0;
1081 u64 *ptr = NULL;
1082 bool readonly = false;
1083
1084 vol_args = memdup_user(arg, sizeof(*vol_args));
1085 if (IS_ERR(vol_args))
1086 return PTR_ERR(vol_args);
1087 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1088
1089 if (vol_args->flags &
1090 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
1091 ret = -EOPNOTSUPP;
1092 goto out;
1093 }
1094
1095 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1096 ptr = &transid;
1097 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1098 readonly = true;
1099
1100 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1101 vol_args->fd, subvol,
1102 ptr, readonly);
1103
1104 if (ret == 0 && ptr &&
1105 copy_to_user(arg +
1106 offsetof(struct btrfs_ioctl_vol_args_v2,
1107 transid), ptr, sizeof(*ptr)))
1108 ret = -EFAULT;
1109 out:
1110 kfree(vol_args);
1111 return ret;
1112 }
1113
1114 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1115 void __user *arg)
1116 {
1117 struct inode *inode = fdentry(file)->d_inode;
1118 struct btrfs_root *root = BTRFS_I(inode)->root;
1119 int ret = 0;
1120 u64 flags = 0;
1121
1122 if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID)
1123 return -EINVAL;
1124
1125 down_read(&root->fs_info->subvol_sem);
1126 if (btrfs_root_readonly(root))
1127 flags |= BTRFS_SUBVOL_RDONLY;
1128 up_read(&root->fs_info->subvol_sem);
1129
1130 if (copy_to_user(arg, &flags, sizeof(flags)))
1131 ret = -EFAULT;
1132
1133 return ret;
1134 }
1135
1136 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1137 void __user *arg)
1138 {
1139 struct inode *inode = fdentry(file)->d_inode;
1140 struct btrfs_root *root = BTRFS_I(inode)->root;
1141 struct btrfs_trans_handle *trans;
1142 u64 root_flags;
1143 u64 flags;
1144 int ret = 0;
1145
1146 if (root->fs_info->sb->s_flags & MS_RDONLY)
1147 return -EROFS;
1148
1149 if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID)
1150 return -EINVAL;
1151
1152 if (copy_from_user(&flags, arg, sizeof(flags)))
1153 return -EFAULT;
1154
1155 if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
1156 return -EINVAL;
1157
1158 if (flags & ~BTRFS_SUBVOL_RDONLY)
1159 return -EOPNOTSUPP;
1160
1161 if (!is_owner_or_cap(inode))
1162 return -EACCES;
1163
1164 down_write(&root->fs_info->subvol_sem);
1165
1166 /* nothing to do */
1167 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1168 goto out;
1169
1170 root_flags = btrfs_root_flags(&root->root_item);
1171 if (flags & BTRFS_SUBVOL_RDONLY)
1172 btrfs_set_root_flags(&root->root_item,
1173 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1174 else
1175 btrfs_set_root_flags(&root->root_item,
1176 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1177
1178 trans = btrfs_start_transaction(root, 1);
1179 if (IS_ERR(trans)) {
1180 ret = PTR_ERR(trans);
1181 goto out_reset;
1182 }
1183
1184 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1185 &root->root_key, &root->root_item);
1186
1187 btrfs_commit_transaction(trans, root);
1188 out_reset:
1189 if (ret)
1190 btrfs_set_root_flags(&root->root_item, root_flags);
1191 out:
1192 up_write(&root->fs_info->subvol_sem);
1193 return ret;
1194 }
1195
1196 /*
1197 * helper to check if the subvolume references other subvolumes
1198 */
1199 static noinline int may_destroy_subvol(struct btrfs_root *root)
1200 {
1201 struct btrfs_path *path;
1202 struct btrfs_key key;
1203 int ret;
1204
1205 path = btrfs_alloc_path();
1206 if (!path)
1207 return -ENOMEM;
1208
1209 key.objectid = root->root_key.objectid;
1210 key.type = BTRFS_ROOT_REF_KEY;
1211 key.offset = (u64)-1;
1212
1213 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1214 &key, path, 0, 0);
1215 if (ret < 0)
1216 goto out;
1217 BUG_ON(ret == 0);
1218
1219 ret = 0;
1220 if (path->slots[0] > 0) {
1221 path->slots[0]--;
1222 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1223 if (key.objectid == root->root_key.objectid &&
1224 key.type == BTRFS_ROOT_REF_KEY)
1225 ret = -ENOTEMPTY;
1226 }
1227 out:
1228 btrfs_free_path(path);
1229 return ret;
1230 }
1231
1232 static noinline int key_in_sk(struct btrfs_key *key,
1233 struct btrfs_ioctl_search_key *sk)
1234 {
1235 struct btrfs_key test;
1236 int ret;
1237
1238 test.objectid = sk->min_objectid;
1239 test.type = sk->min_type;
1240 test.offset = sk->min_offset;
1241
1242 ret = btrfs_comp_cpu_keys(key, &test);
1243 if (ret < 0)
1244 return 0;
1245
1246 test.objectid = sk->max_objectid;
1247 test.type = sk->max_type;
1248 test.offset = sk->max_offset;
1249
1250 ret = btrfs_comp_cpu_keys(key, &test);
1251 if (ret > 0)
1252 return 0;
1253 return 1;
1254 }
1255
1256 static noinline int copy_to_sk(struct btrfs_root *root,
1257 struct btrfs_path *path,
1258 struct btrfs_key *key,
1259 struct btrfs_ioctl_search_key *sk,
1260 char *buf,
1261 unsigned long *sk_offset,
1262 int *num_found)
1263 {
1264 u64 found_transid;
1265 struct extent_buffer *leaf;
1266 struct btrfs_ioctl_search_header sh;
1267 unsigned long item_off;
1268 unsigned long item_len;
1269 int nritems;
1270 int i;
1271 int slot;
1272 int found = 0;
1273 int ret = 0;
1274
1275 leaf = path->nodes[0];
1276 slot = path->slots[0];
1277 nritems = btrfs_header_nritems(leaf);
1278
1279 if (btrfs_header_generation(leaf) > sk->max_transid) {
1280 i = nritems;
1281 goto advance_key;
1282 }
1283 found_transid = btrfs_header_generation(leaf);
1284
1285 for (i = slot; i < nritems; i++) {
1286 item_off = btrfs_item_ptr_offset(leaf, i);
1287 item_len = btrfs_item_size_nr(leaf, i);
1288
1289 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1290 item_len = 0;
1291
1292 if (sizeof(sh) + item_len + *sk_offset >
1293 BTRFS_SEARCH_ARGS_BUFSIZE) {
1294 ret = 1;
1295 goto overflow;
1296 }
1297
1298 btrfs_item_key_to_cpu(leaf, key, i);
1299 if (!key_in_sk(key, sk))
1300 continue;
1301
1302 sh.objectid = key->objectid;
1303 sh.offset = key->offset;
1304 sh.type = key->type;
1305 sh.len = item_len;
1306 sh.transid = found_transid;
1307
1308 /* copy search result header */
1309 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1310 *sk_offset += sizeof(sh);
1311
1312 if (item_len) {
1313 char *p = buf + *sk_offset;
1314 /* copy the item */
1315 read_extent_buffer(leaf, p,
1316 item_off, item_len);
1317 *sk_offset += item_len;
1318 }
1319 found++;
1320
1321 if (*num_found >= sk->nr_items)
1322 break;
1323 }
1324 advance_key:
1325 ret = 0;
1326 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1327 key->offset++;
1328 else if (key->type < (u8)-1 && key->type < sk->max_type) {
1329 key->offset = 0;
1330 key->type++;
1331 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1332 key->offset = 0;
1333 key->type = 0;
1334 key->objectid++;
1335 } else
1336 ret = 1;
1337 overflow:
1338 *num_found += found;
1339 return ret;
1340 }
1341
1342 static noinline int search_ioctl(struct inode *inode,
1343 struct btrfs_ioctl_search_args *args)
1344 {
1345 struct btrfs_root *root;
1346 struct btrfs_key key;
1347 struct btrfs_key max_key;
1348 struct btrfs_path *path;
1349 struct btrfs_ioctl_search_key *sk = &args->key;
1350 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1351 int ret;
1352 int num_found = 0;
1353 unsigned long sk_offset = 0;
1354
1355 path = btrfs_alloc_path();
1356 if (!path)
1357 return -ENOMEM;
1358
1359 if (sk->tree_id == 0) {
1360 /* search the root of the inode that was passed */
1361 root = BTRFS_I(inode)->root;
1362 } else {
1363 key.objectid = sk->tree_id;
1364 key.type = BTRFS_ROOT_ITEM_KEY;
1365 key.offset = (u64)-1;
1366 root = btrfs_read_fs_root_no_name(info, &key);
1367 if (IS_ERR(root)) {
1368 printk(KERN_ERR "could not find root %llu\n",
1369 sk->tree_id);
1370 btrfs_free_path(path);
1371 return -ENOENT;
1372 }
1373 }
1374
1375 key.objectid = sk->min_objectid;
1376 key.type = sk->min_type;
1377 key.offset = sk->min_offset;
1378
1379 max_key.objectid = sk->max_objectid;
1380 max_key.type = sk->max_type;
1381 max_key.offset = sk->max_offset;
1382
1383 path->keep_locks = 1;
1384
1385 while(1) {
1386 ret = btrfs_search_forward(root, &key, &max_key, path, 0,
1387 sk->min_transid);
1388 if (ret != 0) {
1389 if (ret > 0)
1390 ret = 0;
1391 goto err;
1392 }
1393 ret = copy_to_sk(root, path, &key, sk, args->buf,
1394 &sk_offset, &num_found);
1395 btrfs_release_path(root, path);
1396 if (ret || num_found >= sk->nr_items)
1397 break;
1398
1399 }
1400 ret = 0;
1401 err:
1402 sk->nr_items = num_found;
1403 btrfs_free_path(path);
1404 return ret;
1405 }
1406
1407 static noinline int btrfs_ioctl_tree_search(struct file *file,
1408 void __user *argp)
1409 {
1410 struct btrfs_ioctl_search_args *args;
1411 struct inode *inode;
1412 int ret;
1413
1414 if (!capable(CAP_SYS_ADMIN))
1415 return -EPERM;
1416
1417 args = memdup_user(argp, sizeof(*args));
1418 if (IS_ERR(args))
1419 return PTR_ERR(args);
1420
1421 inode = fdentry(file)->d_inode;
1422 ret = search_ioctl(inode, args);
1423 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1424 ret = -EFAULT;
1425 kfree(args);
1426 return ret;
1427 }
1428
1429 /*
1430 * Search INODE_REFs to identify path name of 'dirid' directory
1431 * in a 'tree_id' tree. and sets path name to 'name'.
1432 */
1433 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1434 u64 tree_id, u64 dirid, char *name)
1435 {
1436 struct btrfs_root *root;
1437 struct btrfs_key key;
1438 char *ptr;
1439 int ret = -1;
1440 int slot;
1441 int len;
1442 int total_len = 0;
1443 struct btrfs_inode_ref *iref;
1444 struct extent_buffer *l;
1445 struct btrfs_path *path;
1446
1447 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1448 name[0]='\0';
1449 return 0;
1450 }
1451
1452 path = btrfs_alloc_path();
1453 if (!path)
1454 return -ENOMEM;
1455
1456 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1457
1458 key.objectid = tree_id;
1459 key.type = BTRFS_ROOT_ITEM_KEY;
1460 key.offset = (u64)-1;
1461 root = btrfs_read_fs_root_no_name(info, &key);
1462 if (IS_ERR(root)) {
1463 printk(KERN_ERR "could not find root %llu\n", tree_id);
1464 ret = -ENOENT;
1465 goto out;
1466 }
1467
1468 key.objectid = dirid;
1469 key.type = BTRFS_INODE_REF_KEY;
1470 key.offset = (u64)-1;
1471
1472 while(1) {
1473 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1474 if (ret < 0)
1475 goto out;
1476
1477 l = path->nodes[0];
1478 slot = path->slots[0];
1479 if (ret > 0 && slot > 0)
1480 slot--;
1481 btrfs_item_key_to_cpu(l, &key, slot);
1482
1483 if (ret > 0 && (key.objectid != dirid ||
1484 key.type != BTRFS_INODE_REF_KEY)) {
1485 ret = -ENOENT;
1486 goto out;
1487 }
1488
1489 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1490 len = btrfs_inode_ref_name_len(l, iref);
1491 ptr -= len + 1;
1492 total_len += len + 1;
1493 if (ptr < name)
1494 goto out;
1495
1496 *(ptr + len) = '/';
1497 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1498
1499 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1500 break;
1501
1502 btrfs_release_path(root, path);
1503 key.objectid = key.offset;
1504 key.offset = (u64)-1;
1505 dirid = key.objectid;
1506
1507 }
1508 if (ptr < name)
1509 goto out;
1510 memcpy(name, ptr, total_len);
1511 name[total_len]='\0';
1512 ret = 0;
1513 out:
1514 btrfs_free_path(path);
1515 return ret;
1516 }
1517
1518 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
1519 void __user *argp)
1520 {
1521 struct btrfs_ioctl_ino_lookup_args *args;
1522 struct inode *inode;
1523 int ret;
1524
1525 if (!capable(CAP_SYS_ADMIN))
1526 return -EPERM;
1527
1528 args = memdup_user(argp, sizeof(*args));
1529 if (IS_ERR(args))
1530 return PTR_ERR(args);
1531
1532 inode = fdentry(file)->d_inode;
1533
1534 if (args->treeid == 0)
1535 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
1536
1537 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
1538 args->treeid, args->objectid,
1539 args->name);
1540
1541 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1542 ret = -EFAULT;
1543
1544 kfree(args);
1545 return ret;
1546 }
1547
1548 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
1549 void __user *arg)
1550 {
1551 struct dentry *parent = fdentry(file);
1552 struct dentry *dentry;
1553 struct inode *dir = parent->d_inode;
1554 struct inode *inode;
1555 struct btrfs_root *root = BTRFS_I(dir)->root;
1556 struct btrfs_root *dest = NULL;
1557 struct btrfs_ioctl_vol_args *vol_args;
1558 struct btrfs_trans_handle *trans;
1559 int namelen;
1560 int ret;
1561 int err = 0;
1562
1563 vol_args = memdup_user(arg, sizeof(*vol_args));
1564 if (IS_ERR(vol_args))
1565 return PTR_ERR(vol_args);
1566
1567 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1568 namelen = strlen(vol_args->name);
1569 if (strchr(vol_args->name, '/') ||
1570 strncmp(vol_args->name, "..", namelen) == 0) {
1571 err = -EINVAL;
1572 goto out;
1573 }
1574
1575 err = mnt_want_write(file->f_path.mnt);
1576 if (err)
1577 goto out;
1578
1579 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
1580 dentry = lookup_one_len(vol_args->name, parent, namelen);
1581 if (IS_ERR(dentry)) {
1582 err = PTR_ERR(dentry);
1583 goto out_unlock_dir;
1584 }
1585
1586 if (!dentry->d_inode) {
1587 err = -ENOENT;
1588 goto out_dput;
1589 }
1590
1591 inode = dentry->d_inode;
1592 dest = BTRFS_I(inode)->root;
1593 if (!capable(CAP_SYS_ADMIN)){
1594 /*
1595 * Regular user. Only allow this with a special mount
1596 * option, when the user has write+exec access to the
1597 * subvol root, and when rmdir(2) would have been
1598 * allowed.
1599 *
1600 * Note that this is _not_ check that the subvol is
1601 * empty or doesn't contain data that we wouldn't
1602 * otherwise be able to delete.
1603 *
1604 * Users who want to delete empty subvols should try
1605 * rmdir(2).
1606 */
1607 err = -EPERM;
1608 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
1609 goto out_dput;
1610
1611 /*
1612 * Do not allow deletion if the parent dir is the same
1613 * as the dir to be deleted. That means the ioctl
1614 * must be called on the dentry referencing the root
1615 * of the subvol, not a random directory contained
1616 * within it.
1617 */
1618 err = -EINVAL;
1619 if (root == dest)
1620 goto out_dput;
1621
1622 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
1623 if (err)
1624 goto out_dput;
1625
1626 /* check if subvolume may be deleted by a non-root user */
1627 err = btrfs_may_delete(dir, dentry, 1);
1628 if (err)
1629 goto out_dput;
1630 }
1631
1632 if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) {
1633 err = -EINVAL;
1634 goto out_dput;
1635 }
1636
1637 mutex_lock(&inode->i_mutex);
1638 err = d_invalidate(dentry);
1639 if (err)
1640 goto out_unlock;
1641
1642 down_write(&root->fs_info->subvol_sem);
1643
1644 err = may_destroy_subvol(dest);
1645 if (err)
1646 goto out_up_write;
1647
1648 trans = btrfs_start_transaction(root, 0);
1649 if (IS_ERR(trans)) {
1650 err = PTR_ERR(trans);
1651 goto out_up_write;
1652 }
1653 trans->block_rsv = &root->fs_info->global_block_rsv;
1654
1655 ret = btrfs_unlink_subvol(trans, root, dir,
1656 dest->root_key.objectid,
1657 dentry->d_name.name,
1658 dentry->d_name.len);
1659 BUG_ON(ret);
1660
1661 btrfs_record_root_in_trans(trans, dest);
1662
1663 memset(&dest->root_item.drop_progress, 0,
1664 sizeof(dest->root_item.drop_progress));
1665 dest->root_item.drop_level = 0;
1666 btrfs_set_root_refs(&dest->root_item, 0);
1667
1668 if (!xchg(&dest->orphan_item_inserted, 1)) {
1669 ret = btrfs_insert_orphan_item(trans,
1670 root->fs_info->tree_root,
1671 dest->root_key.objectid);
1672 BUG_ON(ret);
1673 }
1674
1675 ret = btrfs_end_transaction(trans, root);
1676 BUG_ON(ret);
1677 inode->i_flags |= S_DEAD;
1678 out_up_write:
1679 up_write(&root->fs_info->subvol_sem);
1680 out_unlock:
1681 mutex_unlock(&inode->i_mutex);
1682 if (!err) {
1683 shrink_dcache_sb(root->fs_info->sb);
1684 btrfs_invalidate_inodes(dest);
1685 d_delete(dentry);
1686 }
1687 out_dput:
1688 dput(dentry);
1689 out_unlock_dir:
1690 mutex_unlock(&dir->i_mutex);
1691 mnt_drop_write(file->f_path.mnt);
1692 out:
1693 kfree(vol_args);
1694 return err;
1695 }
1696
1697 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
1698 {
1699 struct inode *inode = fdentry(file)->d_inode;
1700 struct btrfs_root *root = BTRFS_I(inode)->root;
1701 struct btrfs_ioctl_defrag_range_args *range;
1702 int ret;
1703
1704 if (btrfs_root_readonly(root))
1705 return -EROFS;
1706
1707 ret = mnt_want_write(file->f_path.mnt);
1708 if (ret)
1709 return ret;
1710
1711 switch (inode->i_mode & S_IFMT) {
1712 case S_IFDIR:
1713 if (!capable(CAP_SYS_ADMIN)) {
1714 ret = -EPERM;
1715 goto out;
1716 }
1717 ret = btrfs_defrag_root(root, 0);
1718 if (ret)
1719 goto out;
1720 ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
1721 break;
1722 case S_IFREG:
1723 if (!(file->f_mode & FMODE_WRITE)) {
1724 ret = -EINVAL;
1725 goto out;
1726 }
1727
1728 range = kzalloc(sizeof(*range), GFP_KERNEL);
1729 if (!range) {
1730 ret = -ENOMEM;
1731 goto out;
1732 }
1733
1734 if (argp) {
1735 if (copy_from_user(range, argp,
1736 sizeof(*range))) {
1737 ret = -EFAULT;
1738 kfree(range);
1739 goto out;
1740 }
1741 /* compression requires us to start the IO */
1742 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1743 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
1744 range->extent_thresh = (u32)-1;
1745 }
1746 } else {
1747 /* the rest are all set to zero by kzalloc */
1748 range->len = (u64)-1;
1749 }
1750 ret = btrfs_defrag_file(file, range);
1751 kfree(range);
1752 break;
1753 default:
1754 ret = -EINVAL;
1755 }
1756 out:
1757 mnt_drop_write(file->f_path.mnt);
1758 return ret;
1759 }
1760
1761 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
1762 {
1763 struct btrfs_ioctl_vol_args *vol_args;
1764 int ret;
1765
1766 if (!capable(CAP_SYS_ADMIN))
1767 return -EPERM;
1768
1769 vol_args = memdup_user(arg, sizeof(*vol_args));
1770 if (IS_ERR(vol_args))
1771 return PTR_ERR(vol_args);
1772
1773 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1774 ret = btrfs_init_new_device(root, vol_args->name);
1775
1776 kfree(vol_args);
1777 return ret;
1778 }
1779
1780 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
1781 {
1782 struct btrfs_ioctl_vol_args *vol_args;
1783 int ret;
1784
1785 if (!capable(CAP_SYS_ADMIN))
1786 return -EPERM;
1787
1788 if (root->fs_info->sb->s_flags & MS_RDONLY)
1789 return -EROFS;
1790
1791 vol_args = memdup_user(arg, sizeof(*vol_args));
1792 if (IS_ERR(vol_args))
1793 return PTR_ERR(vol_args);
1794
1795 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1796 ret = btrfs_rm_device(root, vol_args->name);
1797
1798 kfree(vol_args);
1799 return ret;
1800 }
1801
1802 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
1803 u64 off, u64 olen, u64 destoff)
1804 {
1805 struct inode *inode = fdentry(file)->d_inode;
1806 struct btrfs_root *root = BTRFS_I(inode)->root;
1807 struct file *src_file;
1808 struct inode *src;
1809 struct btrfs_trans_handle *trans;
1810 struct btrfs_path *path;
1811 struct extent_buffer *leaf;
1812 char *buf;
1813 struct btrfs_key key;
1814 u32 nritems;
1815 int slot;
1816 int ret;
1817 u64 len = olen;
1818 u64 bs = root->fs_info->sb->s_blocksize;
1819 u64 hint_byte;
1820
1821 /*
1822 * TODO:
1823 * - split compressed inline extents. annoying: we need to
1824 * decompress into destination's address_space (the file offset
1825 * may change, so source mapping won't do), then recompress (or
1826 * otherwise reinsert) a subrange.
1827 * - allow ranges within the same file to be cloned (provided
1828 * they don't overlap)?
1829 */
1830
1831 /* the destination must be opened for writing */
1832 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
1833 return -EINVAL;
1834
1835 if (btrfs_root_readonly(root))
1836 return -EROFS;
1837
1838 ret = mnt_want_write(file->f_path.mnt);
1839 if (ret)
1840 return ret;
1841
1842 src_file = fget(srcfd);
1843 if (!src_file) {
1844 ret = -EBADF;
1845 goto out_drop_write;
1846 }
1847
1848 src = src_file->f_dentry->d_inode;
1849
1850 ret = -EINVAL;
1851 if (src == inode)
1852 goto out_fput;
1853
1854 /* the src must be open for reading */
1855 if (!(src_file->f_mode & FMODE_READ))
1856 goto out_fput;
1857
1858 ret = -EISDIR;
1859 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
1860 goto out_fput;
1861
1862 ret = -EXDEV;
1863 if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
1864 goto out_fput;
1865
1866 ret = -ENOMEM;
1867 buf = vmalloc(btrfs_level_size(root, 0));
1868 if (!buf)
1869 goto out_fput;
1870
1871 path = btrfs_alloc_path();
1872 if (!path) {
1873 vfree(buf);
1874 goto out_fput;
1875 }
1876 path->reada = 2;
1877
1878 if (inode < src) {
1879 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
1880 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
1881 } else {
1882 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
1883 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
1884 }
1885
1886 /* determine range to clone */
1887 ret = -EINVAL;
1888 if (off + len > src->i_size || off + len < off)
1889 goto out_unlock;
1890 if (len == 0)
1891 olen = len = src->i_size - off;
1892 /* if we extend to eof, continue to block boundary */
1893 if (off + len == src->i_size)
1894 len = ALIGN(src->i_size, bs) - off;
1895
1896 /* verify the end result is block aligned */
1897 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
1898 !IS_ALIGNED(destoff, bs))
1899 goto out_unlock;
1900
1901 /* do any pending delalloc/csum calc on src, one way or
1902 another, and lock file content */
1903 while (1) {
1904 struct btrfs_ordered_extent *ordered;
1905 lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
1906 ordered = btrfs_lookup_first_ordered_extent(src, off+len);
1907 if (!ordered &&
1908 !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len,
1909 EXTENT_DELALLOC, 0, NULL))
1910 break;
1911 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
1912 if (ordered)
1913 btrfs_put_ordered_extent(ordered);
1914 btrfs_wait_ordered_range(src, off, len);
1915 }
1916
1917 /* clone data */
1918 key.objectid = src->i_ino;
1919 key.type = BTRFS_EXTENT_DATA_KEY;
1920 key.offset = 0;
1921
1922 while (1) {
1923 /*
1924 * note the key will change type as we walk through the
1925 * tree.
1926 */
1927 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1928 if (ret < 0)
1929 goto out;
1930
1931 nritems = btrfs_header_nritems(path->nodes[0]);
1932 if (path->slots[0] >= nritems) {
1933 ret = btrfs_next_leaf(root, path);
1934 if (ret < 0)
1935 goto out;
1936 if (ret > 0)
1937 break;
1938 nritems = btrfs_header_nritems(path->nodes[0]);
1939 }
1940 leaf = path->nodes[0];
1941 slot = path->slots[0];
1942
1943 btrfs_item_key_to_cpu(leaf, &key, slot);
1944 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
1945 key.objectid != src->i_ino)
1946 break;
1947
1948 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
1949 struct btrfs_file_extent_item *extent;
1950 int type;
1951 u32 size;
1952 struct btrfs_key new_key;
1953 u64 disko = 0, diskl = 0;
1954 u64 datao = 0, datal = 0;
1955 u8 comp;
1956 u64 endoff;
1957
1958 size = btrfs_item_size_nr(leaf, slot);
1959 read_extent_buffer(leaf, buf,
1960 btrfs_item_ptr_offset(leaf, slot),
1961 size);
1962
1963 extent = btrfs_item_ptr(leaf, slot,
1964 struct btrfs_file_extent_item);
1965 comp = btrfs_file_extent_compression(leaf, extent);
1966 type = btrfs_file_extent_type(leaf, extent);
1967 if (type == BTRFS_FILE_EXTENT_REG ||
1968 type == BTRFS_FILE_EXTENT_PREALLOC) {
1969 disko = btrfs_file_extent_disk_bytenr(leaf,
1970 extent);
1971 diskl = btrfs_file_extent_disk_num_bytes(leaf,
1972 extent);
1973 datao = btrfs_file_extent_offset(leaf, extent);
1974 datal = btrfs_file_extent_num_bytes(leaf,
1975 extent);
1976 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
1977 /* take upper bound, may be compressed */
1978 datal = btrfs_file_extent_ram_bytes(leaf,
1979 extent);
1980 }
1981 btrfs_release_path(root, path);
1982
1983 if (key.offset + datal <= off ||
1984 key.offset >= off+len)
1985 goto next;
1986
1987 memcpy(&new_key, &key, sizeof(new_key));
1988 new_key.objectid = inode->i_ino;
1989 if (off <= key.offset)
1990 new_key.offset = key.offset + destoff - off;
1991 else
1992 new_key.offset = destoff;
1993
1994 trans = btrfs_start_transaction(root, 1);
1995 if (IS_ERR(trans)) {
1996 ret = PTR_ERR(trans);
1997 goto out;
1998 }
1999
2000 if (type == BTRFS_FILE_EXTENT_REG ||
2001 type == BTRFS_FILE_EXTENT_PREALLOC) {
2002 if (off > key.offset) {
2003 datao += off - key.offset;
2004 datal -= off - key.offset;
2005 }
2006
2007 if (key.offset + datal > off + len)
2008 datal = off + len - key.offset;
2009
2010 ret = btrfs_drop_extents(trans, inode,
2011 new_key.offset,
2012 new_key.offset + datal,
2013 &hint_byte, 1);
2014 BUG_ON(ret);
2015
2016 ret = btrfs_insert_empty_item(trans, root, path,
2017 &new_key, size);
2018 BUG_ON(ret);
2019
2020 leaf = path->nodes[0];
2021 slot = path->slots[0];
2022 write_extent_buffer(leaf, buf,
2023 btrfs_item_ptr_offset(leaf, slot),
2024 size);
2025
2026 extent = btrfs_item_ptr(leaf, slot,
2027 struct btrfs_file_extent_item);
2028
2029 /* disko == 0 means it's a hole */
2030 if (!disko)
2031 datao = 0;
2032
2033 btrfs_set_file_extent_offset(leaf, extent,
2034 datao);
2035 btrfs_set_file_extent_num_bytes(leaf, extent,
2036 datal);
2037 if (disko) {
2038 inode_add_bytes(inode, datal);
2039 ret = btrfs_inc_extent_ref(trans, root,
2040 disko, diskl, 0,
2041 root->root_key.objectid,
2042 inode->i_ino,
2043 new_key.offset - datao);
2044 BUG_ON(ret);
2045 }
2046 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2047 u64 skip = 0;
2048 u64 trim = 0;
2049 if (off > key.offset) {
2050 skip = off - key.offset;
2051 new_key.offset += skip;
2052 }
2053
2054 if (key.offset + datal > off+len)
2055 trim = key.offset + datal - (off+len);
2056
2057 if (comp && (skip || trim)) {
2058 ret = -EINVAL;
2059 btrfs_end_transaction(trans, root);
2060 goto out;
2061 }
2062 size -= skip + trim;
2063 datal -= skip + trim;
2064
2065 ret = btrfs_drop_extents(trans, inode,
2066 new_key.offset,
2067 new_key.offset + datal,
2068 &hint_byte, 1);
2069 BUG_ON(ret);
2070
2071 ret = btrfs_insert_empty_item(trans, root, path,
2072 &new_key, size);
2073 BUG_ON(ret);
2074
2075 if (skip) {
2076 u32 start =
2077 btrfs_file_extent_calc_inline_size(0);
2078 memmove(buf+start, buf+start+skip,
2079 datal);
2080 }
2081
2082 leaf = path->nodes[0];
2083 slot = path->slots[0];
2084 write_extent_buffer(leaf, buf,
2085 btrfs_item_ptr_offset(leaf, slot),
2086 size);
2087 inode_add_bytes(inode, datal);
2088 }
2089
2090 btrfs_mark_buffer_dirty(leaf);
2091 btrfs_release_path(root, path);
2092
2093 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2094
2095 /*
2096 * we round up to the block size at eof when
2097 * determining which extents to clone above,
2098 * but shouldn't round up the file size
2099 */
2100 endoff = new_key.offset + datal;
2101 if (endoff > destoff+olen)
2102 endoff = destoff+olen;
2103 if (endoff > inode->i_size)
2104 btrfs_i_size_write(inode, endoff);
2105
2106 BTRFS_I(inode)->flags = BTRFS_I(src)->flags;
2107 ret = btrfs_update_inode(trans, root, inode);
2108 BUG_ON(ret);
2109 btrfs_end_transaction(trans, root);
2110 }
2111 next:
2112 btrfs_release_path(root, path);
2113 key.offset++;
2114 }
2115 ret = 0;
2116 out:
2117 btrfs_release_path(root, path);
2118 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2119 out_unlock:
2120 mutex_unlock(&src->i_mutex);
2121 mutex_unlock(&inode->i_mutex);
2122 vfree(buf);
2123 btrfs_free_path(path);
2124 out_fput:
2125 fput(src_file);
2126 out_drop_write:
2127 mnt_drop_write(file->f_path.mnt);
2128 return ret;
2129 }
2130
2131 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2132 {
2133 struct btrfs_ioctl_clone_range_args args;
2134
2135 if (copy_from_user(&args, argp, sizeof(args)))
2136 return -EFAULT;
2137 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2138 args.src_length, args.dest_offset);
2139 }
2140
2141 /*
2142 * there are many ways the trans_start and trans_end ioctls can lead
2143 * to deadlocks. They should only be used by applications that
2144 * basically own the machine, and have a very in depth understanding
2145 * of all the possible deadlocks and enospc problems.
2146 */
2147 static long btrfs_ioctl_trans_start(struct file *file)
2148 {
2149 struct inode *inode = fdentry(file)->d_inode;
2150 struct btrfs_root *root = BTRFS_I(inode)->root;
2151 struct btrfs_trans_handle *trans;
2152 int ret;
2153
2154 ret = -EPERM;
2155 if (!capable(CAP_SYS_ADMIN))
2156 goto out;
2157
2158 ret = -EINPROGRESS;
2159 if (file->private_data)
2160 goto out;
2161
2162 ret = -EROFS;
2163 if (btrfs_root_readonly(root))
2164 goto out;
2165
2166 ret = mnt_want_write(file->f_path.mnt);
2167 if (ret)
2168 goto out;
2169
2170 mutex_lock(&root->fs_info->trans_mutex);
2171 root->fs_info->open_ioctl_trans++;
2172 mutex_unlock(&root->fs_info->trans_mutex);
2173
2174 ret = -ENOMEM;
2175 trans = btrfs_start_ioctl_transaction(root, 0);
2176 if (IS_ERR(trans))
2177 goto out_drop;
2178
2179 file->private_data = trans;
2180 return 0;
2181
2182 out_drop:
2183 mutex_lock(&root->fs_info->trans_mutex);
2184 root->fs_info->open_ioctl_trans--;
2185 mutex_unlock(&root->fs_info->trans_mutex);
2186 mnt_drop_write(file->f_path.mnt);
2187 out:
2188 return ret;
2189 }
2190
2191 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2192 {
2193 struct inode *inode = fdentry(file)->d_inode;
2194 struct btrfs_root *root = BTRFS_I(inode)->root;
2195 struct btrfs_root *new_root;
2196 struct btrfs_dir_item *di;
2197 struct btrfs_trans_handle *trans;
2198 struct btrfs_path *path;
2199 struct btrfs_key location;
2200 struct btrfs_disk_key disk_key;
2201 struct btrfs_super_block *disk_super;
2202 u64 features;
2203 u64 objectid = 0;
2204 u64 dir_id;
2205
2206 if (!capable(CAP_SYS_ADMIN))
2207 return -EPERM;
2208
2209 if (copy_from_user(&objectid, argp, sizeof(objectid)))
2210 return -EFAULT;
2211
2212 if (!objectid)
2213 objectid = root->root_key.objectid;
2214
2215 location.objectid = objectid;
2216 location.type = BTRFS_ROOT_ITEM_KEY;
2217 location.offset = (u64)-1;
2218
2219 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2220 if (IS_ERR(new_root))
2221 return PTR_ERR(new_root);
2222
2223 if (btrfs_root_refs(&new_root->root_item) == 0)
2224 return -ENOENT;
2225
2226 path = btrfs_alloc_path();
2227 if (!path)
2228 return -ENOMEM;
2229 path->leave_spinning = 1;
2230
2231 trans = btrfs_start_transaction(root, 1);
2232 if (IS_ERR(trans)) {
2233 btrfs_free_path(path);
2234 return PTR_ERR(trans);
2235 }
2236
2237 dir_id = btrfs_super_root_dir(&root->fs_info->super_copy);
2238 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2239 dir_id, "default", 7, 1);
2240 if (IS_ERR_OR_NULL(di)) {
2241 btrfs_free_path(path);
2242 btrfs_end_transaction(trans, root);
2243 printk(KERN_ERR "Umm, you don't have the default dir item, "
2244 "this isn't going to work\n");
2245 return -ENOENT;
2246 }
2247
2248 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2249 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2250 btrfs_mark_buffer_dirty(path->nodes[0]);
2251 btrfs_free_path(path);
2252
2253 disk_super = &root->fs_info->super_copy;
2254 features = btrfs_super_incompat_flags(disk_super);
2255 if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) {
2256 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL;
2257 btrfs_set_super_incompat_flags(disk_super, features);
2258 }
2259 btrfs_end_transaction(trans, root);
2260
2261 return 0;
2262 }
2263
2264 static void get_block_group_info(struct list_head *groups_list,
2265 struct btrfs_ioctl_space_info *space)
2266 {
2267 struct btrfs_block_group_cache *block_group;
2268
2269 space->total_bytes = 0;
2270 space->used_bytes = 0;
2271 space->flags = 0;
2272 list_for_each_entry(block_group, groups_list, list) {
2273 space->flags = block_group->flags;
2274 space->total_bytes += block_group->key.offset;
2275 space->used_bytes +=
2276 btrfs_block_group_used(&block_group->item);
2277 }
2278 }
2279
2280 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
2281 {
2282 struct btrfs_ioctl_space_args space_args;
2283 struct btrfs_ioctl_space_info space;
2284 struct btrfs_ioctl_space_info *dest;
2285 struct btrfs_ioctl_space_info *dest_orig;
2286 struct btrfs_ioctl_space_info *user_dest;
2287 struct btrfs_space_info *info;
2288 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2289 BTRFS_BLOCK_GROUP_SYSTEM,
2290 BTRFS_BLOCK_GROUP_METADATA,
2291 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
2292 int num_types = 4;
2293 int alloc_size;
2294 int ret = 0;
2295 u64 slot_count = 0;
2296 int i, c;
2297
2298 if (copy_from_user(&space_args,
2299 (struct btrfs_ioctl_space_args __user *)arg,
2300 sizeof(space_args)))
2301 return -EFAULT;
2302
2303 for (i = 0; i < num_types; i++) {
2304 struct btrfs_space_info *tmp;
2305
2306 info = NULL;
2307 rcu_read_lock();
2308 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2309 list) {
2310 if (tmp->flags == types[i]) {
2311 info = tmp;
2312 break;
2313 }
2314 }
2315 rcu_read_unlock();
2316
2317 if (!info)
2318 continue;
2319
2320 down_read(&info->groups_sem);
2321 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2322 if (!list_empty(&info->block_groups[c]))
2323 slot_count++;
2324 }
2325 up_read(&info->groups_sem);
2326 }
2327
2328 /* space_slots == 0 means they are asking for a count */
2329 if (space_args.space_slots == 0) {
2330 space_args.total_spaces = slot_count;
2331 goto out;
2332 }
2333
2334 slot_count = min_t(u64, space_args.space_slots, slot_count);
2335
2336 alloc_size = sizeof(*dest) * slot_count;
2337
2338 /* we generally have at most 6 or so space infos, one for each raid
2339 * level. So, a whole page should be more than enough for everyone
2340 */
2341 if (alloc_size > PAGE_CACHE_SIZE)
2342 return -ENOMEM;
2343
2344 space_args.total_spaces = 0;
2345 dest = kmalloc(alloc_size, GFP_NOFS);
2346 if (!dest)
2347 return -ENOMEM;
2348 dest_orig = dest;
2349
2350 /* now we have a buffer to copy into */
2351 for (i = 0; i < num_types; i++) {
2352 struct btrfs_space_info *tmp;
2353
2354 if (!slot_count)
2355 break;
2356
2357 info = NULL;
2358 rcu_read_lock();
2359 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2360 list) {
2361 if (tmp->flags == types[i]) {
2362 info = tmp;
2363 break;
2364 }
2365 }
2366 rcu_read_unlock();
2367
2368 if (!info)
2369 continue;
2370 down_read(&info->groups_sem);
2371 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2372 if (!list_empty(&info->block_groups[c])) {
2373 get_block_group_info(&info->block_groups[c],
2374 &space);
2375 memcpy(dest, &space, sizeof(space));
2376 dest++;
2377 space_args.total_spaces++;
2378 slot_count--;
2379 }
2380 if (!slot_count)
2381 break;
2382 }
2383 up_read(&info->groups_sem);
2384 }
2385
2386 user_dest = (struct btrfs_ioctl_space_info *)
2387 (arg + sizeof(struct btrfs_ioctl_space_args));
2388
2389 if (copy_to_user(user_dest, dest_orig, alloc_size))
2390 ret = -EFAULT;
2391
2392 kfree(dest_orig);
2393 out:
2394 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
2395 ret = -EFAULT;
2396
2397 return ret;
2398 }
2399
2400 /*
2401 * there are many ways the trans_start and trans_end ioctls can lead
2402 * to deadlocks. They should only be used by applications that
2403 * basically own the machine, and have a very in depth understanding
2404 * of all the possible deadlocks and enospc problems.
2405 */
2406 long btrfs_ioctl_trans_end(struct file *file)
2407 {
2408 struct inode *inode = fdentry(file)->d_inode;
2409 struct btrfs_root *root = BTRFS_I(inode)->root;
2410 struct btrfs_trans_handle *trans;
2411
2412 trans = file->private_data;
2413 if (!trans)
2414 return -EINVAL;
2415 file->private_data = NULL;
2416
2417 btrfs_end_transaction(trans, root);
2418
2419 mutex_lock(&root->fs_info->trans_mutex);
2420 root->fs_info->open_ioctl_trans--;
2421 mutex_unlock(&root->fs_info->trans_mutex);
2422
2423 mnt_drop_write(file->f_path.mnt);
2424 return 0;
2425 }
2426
2427 static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
2428 {
2429 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2430 struct btrfs_trans_handle *trans;
2431 u64 transid;
2432 int ret;
2433
2434 trans = btrfs_start_transaction(root, 0);
2435 if (IS_ERR(trans))
2436 return PTR_ERR(trans);
2437 transid = trans->transid;
2438 ret = btrfs_commit_transaction_async(trans, root, 0);
2439 if (ret)
2440 return ret;
2441
2442 if (argp)
2443 if (copy_to_user(argp, &transid, sizeof(transid)))
2444 return -EFAULT;
2445 return 0;
2446 }
2447
2448 static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
2449 {
2450 struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2451 u64 transid;
2452
2453 if (argp) {
2454 if (copy_from_user(&transid, argp, sizeof(transid)))
2455 return -EFAULT;
2456 } else {
2457 transid = 0; /* current trans */
2458 }
2459 return btrfs_wait_for_commit(root, transid);
2460 }
2461
2462 long btrfs_ioctl(struct file *file, unsigned int
2463 cmd, unsigned long arg)
2464 {
2465 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2466 void __user *argp = (void __user *)arg;
2467
2468 switch (cmd) {
2469 case FS_IOC_GETFLAGS:
2470 return btrfs_ioctl_getflags(file, argp);
2471 case FS_IOC_SETFLAGS:
2472 return btrfs_ioctl_setflags(file, argp);
2473 case FS_IOC_GETVERSION:
2474 return btrfs_ioctl_getversion(file, argp);
2475 case FITRIM:
2476 return btrfs_ioctl_fitrim(file, argp);
2477 case BTRFS_IOC_SNAP_CREATE:
2478 return btrfs_ioctl_snap_create(file, argp, 0);
2479 case BTRFS_IOC_SNAP_CREATE_V2:
2480 return btrfs_ioctl_snap_create_v2(file, argp, 0);
2481 case BTRFS_IOC_SUBVOL_CREATE:
2482 return btrfs_ioctl_snap_create(file, argp, 1);
2483 case BTRFS_IOC_SNAP_DESTROY:
2484 return btrfs_ioctl_snap_destroy(file, argp);
2485 case BTRFS_IOC_SUBVOL_GETFLAGS:
2486 return btrfs_ioctl_subvol_getflags(file, argp);
2487 case BTRFS_IOC_SUBVOL_SETFLAGS:
2488 return btrfs_ioctl_subvol_setflags(file, argp);
2489 case BTRFS_IOC_DEFAULT_SUBVOL:
2490 return btrfs_ioctl_default_subvol(file, argp);
2491 case BTRFS_IOC_DEFRAG:
2492 return btrfs_ioctl_defrag(file, NULL);
2493 case BTRFS_IOC_DEFRAG_RANGE:
2494 return btrfs_ioctl_defrag(file, argp);
2495 case BTRFS_IOC_RESIZE:
2496 return btrfs_ioctl_resize(root, argp);
2497 case BTRFS_IOC_ADD_DEV:
2498 return btrfs_ioctl_add_dev(root, argp);
2499 case BTRFS_IOC_RM_DEV:
2500 return btrfs_ioctl_rm_dev(root, argp);
2501 case BTRFS_IOC_BALANCE:
2502 return btrfs_balance(root->fs_info->dev_root);
2503 case BTRFS_IOC_CLONE:
2504 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
2505 case BTRFS_IOC_CLONE_RANGE:
2506 return btrfs_ioctl_clone_range(file, argp);
2507 case BTRFS_IOC_TRANS_START:
2508 return btrfs_ioctl_trans_start(file);
2509 case BTRFS_IOC_TRANS_END:
2510 return btrfs_ioctl_trans_end(file);
2511 case BTRFS_IOC_TREE_SEARCH:
2512 return btrfs_ioctl_tree_search(file, argp);
2513 case BTRFS_IOC_INO_LOOKUP:
2514 return btrfs_ioctl_ino_lookup(file, argp);
2515 case BTRFS_IOC_SPACE_INFO:
2516 return btrfs_ioctl_space_info(root, argp);
2517 case BTRFS_IOC_SYNC:
2518 btrfs_sync_fs(file->f_dentry->d_sb, 1);
2519 return 0;
2520 case BTRFS_IOC_START_SYNC:
2521 return btrfs_ioctl_start_sync(file, argp);
2522 case BTRFS_IOC_WAIT_SYNC:
2523 return btrfs_ioctl_wait_sync(file, argp);
2524 }
2525
2526 return -ENOTTY;
2527 }
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