xref: /openbmc/linux/fs/btrfs/ioctl.c (revision e8e0929d)
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 "compat.h"
43 #include "ctree.h"
44 #include "disk-io.h"
45 #include "transaction.h"
46 #include "btrfs_inode.h"
47 #include "ioctl.h"
48 #include "print-tree.h"
49 #include "volumes.h"
50 #include "locking.h"
51 
52 /* Mask out flags that are inappropriate for the given type of inode. */
53 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
54 {
55 	if (S_ISDIR(mode))
56 		return flags;
57 	else if (S_ISREG(mode))
58 		return flags & ~FS_DIRSYNC_FL;
59 	else
60 		return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
61 }
62 
63 /*
64  * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
65  */
66 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
67 {
68 	unsigned int iflags = 0;
69 
70 	if (flags & BTRFS_INODE_SYNC)
71 		iflags |= FS_SYNC_FL;
72 	if (flags & BTRFS_INODE_IMMUTABLE)
73 		iflags |= FS_IMMUTABLE_FL;
74 	if (flags & BTRFS_INODE_APPEND)
75 		iflags |= FS_APPEND_FL;
76 	if (flags & BTRFS_INODE_NODUMP)
77 		iflags |= FS_NODUMP_FL;
78 	if (flags & BTRFS_INODE_NOATIME)
79 		iflags |= FS_NOATIME_FL;
80 	if (flags & BTRFS_INODE_DIRSYNC)
81 		iflags |= FS_DIRSYNC_FL;
82 
83 	return iflags;
84 }
85 
86 /*
87  * Update inode->i_flags based on the btrfs internal flags.
88  */
89 void btrfs_update_iflags(struct inode *inode)
90 {
91 	struct btrfs_inode *ip = BTRFS_I(inode);
92 
93 	inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
94 
95 	if (ip->flags & BTRFS_INODE_SYNC)
96 		inode->i_flags |= S_SYNC;
97 	if (ip->flags & BTRFS_INODE_IMMUTABLE)
98 		inode->i_flags |= S_IMMUTABLE;
99 	if (ip->flags & BTRFS_INODE_APPEND)
100 		inode->i_flags |= S_APPEND;
101 	if (ip->flags & BTRFS_INODE_NOATIME)
102 		inode->i_flags |= S_NOATIME;
103 	if (ip->flags & BTRFS_INODE_DIRSYNC)
104 		inode->i_flags |= S_DIRSYNC;
105 }
106 
107 /*
108  * Inherit flags from the parent inode.
109  *
110  * Unlike extN we don't have any flags we don't want to inherit currently.
111  */
112 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
113 {
114 	unsigned int flags;
115 
116 	if (!dir)
117 		return;
118 
119 	flags = BTRFS_I(dir)->flags;
120 
121 	if (S_ISREG(inode->i_mode))
122 		flags &= ~BTRFS_INODE_DIRSYNC;
123 	else if (!S_ISDIR(inode->i_mode))
124 		flags &= (BTRFS_INODE_NODUMP | BTRFS_INODE_NOATIME);
125 
126 	BTRFS_I(inode)->flags = flags;
127 	btrfs_update_iflags(inode);
128 }
129 
130 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
131 {
132 	struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
133 	unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
134 
135 	if (copy_to_user(arg, &flags, sizeof(flags)))
136 		return -EFAULT;
137 	return 0;
138 }
139 
140 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
141 {
142 	struct inode *inode = file->f_path.dentry->d_inode;
143 	struct btrfs_inode *ip = BTRFS_I(inode);
144 	struct btrfs_root *root = ip->root;
145 	struct btrfs_trans_handle *trans;
146 	unsigned int flags, oldflags;
147 	int ret;
148 
149 	if (copy_from_user(&flags, arg, sizeof(flags)))
150 		return -EFAULT;
151 
152 	if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
153 		      FS_NOATIME_FL | FS_NODUMP_FL | \
154 		      FS_SYNC_FL | FS_DIRSYNC_FL))
155 		return -EOPNOTSUPP;
156 
157 	if (!is_owner_or_cap(inode))
158 		return -EACCES;
159 
160 	mutex_lock(&inode->i_mutex);
161 
162 	flags = btrfs_mask_flags(inode->i_mode, flags);
163 	oldflags = btrfs_flags_to_ioctl(ip->flags);
164 	if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
165 		if (!capable(CAP_LINUX_IMMUTABLE)) {
166 			ret = -EPERM;
167 			goto out_unlock;
168 		}
169 	}
170 
171 	ret = mnt_want_write(file->f_path.mnt);
172 	if (ret)
173 		goto out_unlock;
174 
175 	if (flags & FS_SYNC_FL)
176 		ip->flags |= BTRFS_INODE_SYNC;
177 	else
178 		ip->flags &= ~BTRFS_INODE_SYNC;
179 	if (flags & FS_IMMUTABLE_FL)
180 		ip->flags |= BTRFS_INODE_IMMUTABLE;
181 	else
182 		ip->flags &= ~BTRFS_INODE_IMMUTABLE;
183 	if (flags & FS_APPEND_FL)
184 		ip->flags |= BTRFS_INODE_APPEND;
185 	else
186 		ip->flags &= ~BTRFS_INODE_APPEND;
187 	if (flags & FS_NODUMP_FL)
188 		ip->flags |= BTRFS_INODE_NODUMP;
189 	else
190 		ip->flags &= ~BTRFS_INODE_NODUMP;
191 	if (flags & FS_NOATIME_FL)
192 		ip->flags |= BTRFS_INODE_NOATIME;
193 	else
194 		ip->flags &= ~BTRFS_INODE_NOATIME;
195 	if (flags & FS_DIRSYNC_FL)
196 		ip->flags |= BTRFS_INODE_DIRSYNC;
197 	else
198 		ip->flags &= ~BTRFS_INODE_DIRSYNC;
199 
200 
201 	trans = btrfs_join_transaction(root, 1);
202 	BUG_ON(!trans);
203 
204 	ret = btrfs_update_inode(trans, root, inode);
205 	BUG_ON(ret);
206 
207 	btrfs_update_iflags(inode);
208 	inode->i_ctime = CURRENT_TIME;
209 	btrfs_end_transaction(trans, root);
210 
211 	mnt_drop_write(file->f_path.mnt);
212  out_unlock:
213 	mutex_unlock(&inode->i_mutex);
214 	return 0;
215 }
216 
217 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
218 {
219 	struct inode *inode = file->f_path.dentry->d_inode;
220 
221 	return put_user(inode->i_generation, arg);
222 }
223 
224 static noinline int create_subvol(struct btrfs_root *root,
225 				  struct dentry *dentry,
226 				  char *name, int namelen)
227 {
228 	struct btrfs_trans_handle *trans;
229 	struct btrfs_key key;
230 	struct btrfs_root_item root_item;
231 	struct btrfs_inode_item *inode_item;
232 	struct extent_buffer *leaf;
233 	struct btrfs_root *new_root;
234 	struct inode *dir = dentry->d_parent->d_inode;
235 	int ret;
236 	int err;
237 	u64 objectid;
238 	u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
239 	u64 index = 0;
240 	unsigned long nr = 1;
241 
242 	/*
243 	 * 1 - inode item
244 	 * 2 - refs
245 	 * 1 - root item
246 	 * 2 - dir items
247 	 */
248 	ret = btrfs_reserve_metadata_space(root, 6);
249 	if (ret)
250 		return ret;
251 
252 	trans = btrfs_start_transaction(root, 1);
253 	BUG_ON(!trans);
254 
255 	ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
256 				       0, &objectid);
257 	if (ret)
258 		goto fail;
259 
260 	leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
261 				      0, objectid, NULL, 0, 0, 0);
262 	if (IS_ERR(leaf)) {
263 		ret = PTR_ERR(leaf);
264 		goto fail;
265 	}
266 
267 	memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
268 	btrfs_set_header_bytenr(leaf, leaf->start);
269 	btrfs_set_header_generation(leaf, trans->transid);
270 	btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
271 	btrfs_set_header_owner(leaf, objectid);
272 
273 	write_extent_buffer(leaf, root->fs_info->fsid,
274 			    (unsigned long)btrfs_header_fsid(leaf),
275 			    BTRFS_FSID_SIZE);
276 	write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
277 			    (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
278 			    BTRFS_UUID_SIZE);
279 	btrfs_mark_buffer_dirty(leaf);
280 
281 	inode_item = &root_item.inode;
282 	memset(inode_item, 0, sizeof(*inode_item));
283 	inode_item->generation = cpu_to_le64(1);
284 	inode_item->size = cpu_to_le64(3);
285 	inode_item->nlink = cpu_to_le32(1);
286 	inode_item->nbytes = cpu_to_le64(root->leafsize);
287 	inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
288 
289 	btrfs_set_root_bytenr(&root_item, leaf->start);
290 	btrfs_set_root_generation(&root_item, trans->transid);
291 	btrfs_set_root_level(&root_item, 0);
292 	btrfs_set_root_refs(&root_item, 1);
293 	btrfs_set_root_used(&root_item, 0);
294 	btrfs_set_root_last_snapshot(&root_item, 0);
295 
296 	memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
297 	root_item.drop_level = 0;
298 
299 	btrfs_tree_unlock(leaf);
300 	free_extent_buffer(leaf);
301 	leaf = NULL;
302 
303 	btrfs_set_root_dirid(&root_item, new_dirid);
304 
305 	key.objectid = objectid;
306 	key.offset = 0;
307 	btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
308 	ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
309 				&root_item);
310 	if (ret)
311 		goto fail;
312 
313 	key.offset = (u64)-1;
314 	new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
315 	BUG_ON(IS_ERR(new_root));
316 
317 	btrfs_record_root_in_trans(trans, new_root);
318 
319 	ret = btrfs_create_subvol_root(trans, new_root, new_dirid,
320 				       BTRFS_I(dir)->block_group);
321 	/*
322 	 * insert the directory item
323 	 */
324 	ret = btrfs_set_inode_index(dir, &index);
325 	BUG_ON(ret);
326 
327 	ret = btrfs_insert_dir_item(trans, root,
328 				    name, namelen, dir->i_ino, &key,
329 				    BTRFS_FT_DIR, index);
330 	if (ret)
331 		goto fail;
332 
333 	btrfs_i_size_write(dir, dir->i_size + namelen * 2);
334 	ret = btrfs_update_inode(trans, root, dir);
335 	BUG_ON(ret);
336 
337 	ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
338 				 objectid, root->root_key.objectid,
339 				 dir->i_ino, index, name, namelen);
340 
341 	BUG_ON(ret);
342 
343 	d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
344 fail:
345 	nr = trans->blocks_used;
346 	err = btrfs_commit_transaction(trans, root);
347 	if (err && !ret)
348 		ret = err;
349 
350 	btrfs_unreserve_metadata_space(root, 6);
351 	btrfs_btree_balance_dirty(root, nr);
352 	return ret;
353 }
354 
355 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
356 			   char *name, int namelen)
357 {
358 	struct btrfs_pending_snapshot *pending_snapshot;
359 	struct btrfs_trans_handle *trans;
360 	int ret = 0;
361 	int err;
362 	unsigned long nr = 0;
363 
364 	if (!root->ref_cows)
365 		return -EINVAL;
366 
367 	/*
368 	 * 1 - inode item
369 	 * 2 - refs
370 	 * 1 - root item
371 	 * 2 - dir items
372 	 */
373 	ret = btrfs_reserve_metadata_space(root, 6);
374 	if (ret)
375 		goto fail_unlock;
376 
377 	pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
378 	if (!pending_snapshot) {
379 		ret = -ENOMEM;
380 		btrfs_unreserve_metadata_space(root, 6);
381 		goto fail_unlock;
382 	}
383 	pending_snapshot->name = kmalloc(namelen + 1, GFP_NOFS);
384 	if (!pending_snapshot->name) {
385 		ret = -ENOMEM;
386 		kfree(pending_snapshot);
387 		btrfs_unreserve_metadata_space(root, 6);
388 		goto fail_unlock;
389 	}
390 	memcpy(pending_snapshot->name, name, namelen);
391 	pending_snapshot->name[namelen] = '\0';
392 	pending_snapshot->dentry = dentry;
393 	trans = btrfs_start_transaction(root, 1);
394 	BUG_ON(!trans);
395 	pending_snapshot->root = root;
396 	list_add(&pending_snapshot->list,
397 		 &trans->transaction->pending_snapshots);
398 	err = btrfs_commit_transaction(trans, root);
399 
400 fail_unlock:
401 	btrfs_btree_balance_dirty(root, nr);
402 	return ret;
403 }
404 
405 /* copy of may_create in fs/namei.c() */
406 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
407 {
408 	if (child->d_inode)
409 		return -EEXIST;
410 	if (IS_DEADDIR(dir))
411 		return -ENOENT;
412 	return inode_permission(dir, MAY_WRITE | MAY_EXEC);
413 }
414 
415 /*
416  * Create a new subvolume below @parent.  This is largely modeled after
417  * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
418  * inside this filesystem so it's quite a bit simpler.
419  */
420 static noinline int btrfs_mksubvol(struct path *parent,
421 				   char *name, int namelen,
422 				   struct btrfs_root *snap_src)
423 {
424 	struct inode *dir  = parent->dentry->d_inode;
425 	struct dentry *dentry;
426 	int error;
427 
428 	mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
429 
430 	dentry = lookup_one_len(name, parent->dentry, namelen);
431 	error = PTR_ERR(dentry);
432 	if (IS_ERR(dentry))
433 		goto out_unlock;
434 
435 	error = -EEXIST;
436 	if (dentry->d_inode)
437 		goto out_dput;
438 
439 	error = mnt_want_write(parent->mnt);
440 	if (error)
441 		goto out_dput;
442 
443 	error = btrfs_may_create(dir, dentry);
444 	if (error)
445 		goto out_drop_write;
446 
447 	down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
448 
449 	if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
450 		goto out_up_read;
451 
452 	if (snap_src) {
453 		error = create_snapshot(snap_src, dentry,
454 					name, namelen);
455 	} else {
456 		error = create_subvol(BTRFS_I(dir)->root, dentry,
457 				      name, namelen);
458 	}
459 	if (!error)
460 		fsnotify_mkdir(dir, dentry);
461 out_up_read:
462 	up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
463 out_drop_write:
464 	mnt_drop_write(parent->mnt);
465 out_dput:
466 	dput(dentry);
467 out_unlock:
468 	mutex_unlock(&dir->i_mutex);
469 	return error;
470 }
471 
472 static int btrfs_defrag_file(struct file *file)
473 {
474 	struct inode *inode = fdentry(file)->d_inode;
475 	struct btrfs_root *root = BTRFS_I(inode)->root;
476 	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
477 	struct btrfs_ordered_extent *ordered;
478 	struct page *page;
479 	unsigned long last_index;
480 	unsigned long ra_pages = root->fs_info->bdi.ra_pages;
481 	unsigned long total_read = 0;
482 	u64 page_start;
483 	u64 page_end;
484 	unsigned long i;
485 	int ret;
486 
487 	ret = btrfs_check_data_free_space(root, inode, inode->i_size);
488 	if (ret)
489 		return -ENOSPC;
490 
491 	mutex_lock(&inode->i_mutex);
492 	last_index = inode->i_size >> PAGE_CACHE_SHIFT;
493 	for (i = 0; i <= last_index; i++) {
494 		if (total_read % ra_pages == 0) {
495 			btrfs_force_ra(inode->i_mapping, &file->f_ra, file, i,
496 				       min(last_index, i + ra_pages - 1));
497 		}
498 		total_read++;
499 again:
500 		page = grab_cache_page(inode->i_mapping, i);
501 		if (!page)
502 			goto out_unlock;
503 		if (!PageUptodate(page)) {
504 			btrfs_readpage(NULL, page);
505 			lock_page(page);
506 			if (!PageUptodate(page)) {
507 				unlock_page(page);
508 				page_cache_release(page);
509 				goto out_unlock;
510 			}
511 		}
512 
513 		wait_on_page_writeback(page);
514 
515 		page_start = (u64)page->index << PAGE_CACHE_SHIFT;
516 		page_end = page_start + PAGE_CACHE_SIZE - 1;
517 		lock_extent(io_tree, page_start, page_end, GFP_NOFS);
518 
519 		ordered = btrfs_lookup_ordered_extent(inode, page_start);
520 		if (ordered) {
521 			unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
522 			unlock_page(page);
523 			page_cache_release(page);
524 			btrfs_start_ordered_extent(inode, ordered, 1);
525 			btrfs_put_ordered_extent(ordered);
526 			goto again;
527 		}
528 		set_page_extent_mapped(page);
529 
530 		/*
531 		 * this makes sure page_mkwrite is called on the
532 		 * page if it is dirtied again later
533 		 */
534 		clear_page_dirty_for_io(page);
535 
536 		btrfs_set_extent_delalloc(inode, page_start, page_end);
537 		set_page_dirty(page);
538 		unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
539 		unlock_page(page);
540 		page_cache_release(page);
541 		balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);
542 	}
543 
544 out_unlock:
545 	mutex_unlock(&inode->i_mutex);
546 	return 0;
547 }
548 
549 static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
550 					void __user *arg)
551 {
552 	u64 new_size;
553 	u64 old_size;
554 	u64 devid = 1;
555 	struct btrfs_ioctl_vol_args *vol_args;
556 	struct btrfs_trans_handle *trans;
557 	struct btrfs_device *device = NULL;
558 	char *sizestr;
559 	char *devstr = NULL;
560 	int ret = 0;
561 	int namelen;
562 	int mod = 0;
563 
564 	if (root->fs_info->sb->s_flags & MS_RDONLY)
565 		return -EROFS;
566 
567 	if (!capable(CAP_SYS_ADMIN))
568 		return -EPERM;
569 
570 	vol_args = memdup_user(arg, sizeof(*vol_args));
571 	if (IS_ERR(vol_args))
572 		return PTR_ERR(vol_args);
573 
574 	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
575 	namelen = strlen(vol_args->name);
576 
577 	mutex_lock(&root->fs_info->volume_mutex);
578 	sizestr = vol_args->name;
579 	devstr = strchr(sizestr, ':');
580 	if (devstr) {
581 		char *end;
582 		sizestr = devstr + 1;
583 		*devstr = '\0';
584 		devstr = vol_args->name;
585 		devid = simple_strtoull(devstr, &end, 10);
586 		printk(KERN_INFO "resizing devid %llu\n",
587 		       (unsigned long long)devid);
588 	}
589 	device = btrfs_find_device(root, devid, NULL, NULL);
590 	if (!device) {
591 		printk(KERN_INFO "resizer unable to find device %llu\n",
592 		       (unsigned long long)devid);
593 		ret = -EINVAL;
594 		goto out_unlock;
595 	}
596 	if (!strcmp(sizestr, "max"))
597 		new_size = device->bdev->bd_inode->i_size;
598 	else {
599 		if (sizestr[0] == '-') {
600 			mod = -1;
601 			sizestr++;
602 		} else if (sizestr[0] == '+') {
603 			mod = 1;
604 			sizestr++;
605 		}
606 		new_size = btrfs_parse_size(sizestr);
607 		if (new_size == 0) {
608 			ret = -EINVAL;
609 			goto out_unlock;
610 		}
611 	}
612 
613 	old_size = device->total_bytes;
614 
615 	if (mod < 0) {
616 		if (new_size > old_size) {
617 			ret = -EINVAL;
618 			goto out_unlock;
619 		}
620 		new_size = old_size - new_size;
621 	} else if (mod > 0) {
622 		new_size = old_size + new_size;
623 	}
624 
625 	if (new_size < 256 * 1024 * 1024) {
626 		ret = -EINVAL;
627 		goto out_unlock;
628 	}
629 	if (new_size > device->bdev->bd_inode->i_size) {
630 		ret = -EFBIG;
631 		goto out_unlock;
632 	}
633 
634 	do_div(new_size, root->sectorsize);
635 	new_size *= root->sectorsize;
636 
637 	printk(KERN_INFO "new size for %s is %llu\n",
638 		device->name, (unsigned long long)new_size);
639 
640 	if (new_size > old_size) {
641 		trans = btrfs_start_transaction(root, 1);
642 		ret = btrfs_grow_device(trans, device, new_size);
643 		btrfs_commit_transaction(trans, root);
644 	} else {
645 		ret = btrfs_shrink_device(device, new_size);
646 	}
647 
648 out_unlock:
649 	mutex_unlock(&root->fs_info->volume_mutex);
650 	kfree(vol_args);
651 	return ret;
652 }
653 
654 static noinline int btrfs_ioctl_snap_create(struct file *file,
655 					    void __user *arg, int subvol)
656 {
657 	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
658 	struct btrfs_ioctl_vol_args *vol_args;
659 	struct file *src_file;
660 	int namelen;
661 	int ret = 0;
662 
663 	if (root->fs_info->sb->s_flags & MS_RDONLY)
664 		return -EROFS;
665 
666 	vol_args = memdup_user(arg, sizeof(*vol_args));
667 	if (IS_ERR(vol_args))
668 		return PTR_ERR(vol_args);
669 
670 	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
671 	namelen = strlen(vol_args->name);
672 	if (strchr(vol_args->name, '/')) {
673 		ret = -EINVAL;
674 		goto out;
675 	}
676 
677 	if (subvol) {
678 		ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen,
679 				     NULL);
680 	} else {
681 		struct inode *src_inode;
682 		src_file = fget(vol_args->fd);
683 		if (!src_file) {
684 			ret = -EINVAL;
685 			goto out;
686 		}
687 
688 		src_inode = src_file->f_path.dentry->d_inode;
689 		if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
690 			printk(KERN_INFO "btrfs: Snapshot src from "
691 			       "another FS\n");
692 			ret = -EINVAL;
693 			fput(src_file);
694 			goto out;
695 		}
696 		ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen,
697 				     BTRFS_I(src_inode)->root);
698 		fput(src_file);
699 	}
700 out:
701 	kfree(vol_args);
702 	return ret;
703 }
704 
705 /*
706  * helper to check if the subvolume references other subvolumes
707  */
708 static noinline int may_destroy_subvol(struct btrfs_root *root)
709 {
710 	struct btrfs_path *path;
711 	struct btrfs_key key;
712 	int ret;
713 
714 	path = btrfs_alloc_path();
715 	if (!path)
716 		return -ENOMEM;
717 
718 	key.objectid = root->root_key.objectid;
719 	key.type = BTRFS_ROOT_REF_KEY;
720 	key.offset = (u64)-1;
721 
722 	ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
723 				&key, path, 0, 0);
724 	if (ret < 0)
725 		goto out;
726 	BUG_ON(ret == 0);
727 
728 	ret = 0;
729 	if (path->slots[0] > 0) {
730 		path->slots[0]--;
731 		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
732 		if (key.objectid == root->root_key.objectid &&
733 		    key.type == BTRFS_ROOT_REF_KEY)
734 			ret = -ENOTEMPTY;
735 	}
736 out:
737 	btrfs_free_path(path);
738 	return ret;
739 }
740 
741 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
742 					     void __user *arg)
743 {
744 	struct dentry *parent = fdentry(file);
745 	struct dentry *dentry;
746 	struct inode *dir = parent->d_inode;
747 	struct inode *inode;
748 	struct btrfs_root *root = BTRFS_I(dir)->root;
749 	struct btrfs_root *dest = NULL;
750 	struct btrfs_ioctl_vol_args *vol_args;
751 	struct btrfs_trans_handle *trans;
752 	int namelen;
753 	int ret;
754 	int err = 0;
755 
756 	if (!capable(CAP_SYS_ADMIN))
757 		return -EPERM;
758 
759 	vol_args = memdup_user(arg, sizeof(*vol_args));
760 	if (IS_ERR(vol_args))
761 		return PTR_ERR(vol_args);
762 
763 	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
764 	namelen = strlen(vol_args->name);
765 	if (strchr(vol_args->name, '/') ||
766 	    strncmp(vol_args->name, "..", namelen) == 0) {
767 		err = -EINVAL;
768 		goto out;
769 	}
770 
771 	err = mnt_want_write(file->f_path.mnt);
772 	if (err)
773 		goto out;
774 
775 	mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
776 	dentry = lookup_one_len(vol_args->name, parent, namelen);
777 	if (IS_ERR(dentry)) {
778 		err = PTR_ERR(dentry);
779 		goto out_unlock_dir;
780 	}
781 
782 	if (!dentry->d_inode) {
783 		err = -ENOENT;
784 		goto out_dput;
785 	}
786 
787 	inode = dentry->d_inode;
788 	if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) {
789 		err = -EINVAL;
790 		goto out_dput;
791 	}
792 
793 	dest = BTRFS_I(inode)->root;
794 
795 	mutex_lock(&inode->i_mutex);
796 	err = d_invalidate(dentry);
797 	if (err)
798 		goto out_unlock;
799 
800 	down_write(&root->fs_info->subvol_sem);
801 
802 	err = may_destroy_subvol(dest);
803 	if (err)
804 		goto out_up_write;
805 
806 	trans = btrfs_start_transaction(root, 1);
807 	ret = btrfs_unlink_subvol(trans, root, dir,
808 				dest->root_key.objectid,
809 				dentry->d_name.name,
810 				dentry->d_name.len);
811 	BUG_ON(ret);
812 
813 	btrfs_record_root_in_trans(trans, dest);
814 
815 	memset(&dest->root_item.drop_progress, 0,
816 		sizeof(dest->root_item.drop_progress));
817 	dest->root_item.drop_level = 0;
818 	btrfs_set_root_refs(&dest->root_item, 0);
819 
820 	ret = btrfs_insert_orphan_item(trans,
821 				root->fs_info->tree_root,
822 				dest->root_key.objectid);
823 	BUG_ON(ret);
824 
825 	ret = btrfs_commit_transaction(trans, root);
826 	BUG_ON(ret);
827 	inode->i_flags |= S_DEAD;
828 out_up_write:
829 	up_write(&root->fs_info->subvol_sem);
830 out_unlock:
831 	mutex_unlock(&inode->i_mutex);
832 	if (!err) {
833 		btrfs_invalidate_inodes(dest);
834 		d_delete(dentry);
835 	}
836 out_dput:
837 	dput(dentry);
838 out_unlock_dir:
839 	mutex_unlock(&dir->i_mutex);
840 	mnt_drop_write(file->f_path.mnt);
841 out:
842 	kfree(vol_args);
843 	return err;
844 }
845 
846 static int btrfs_ioctl_defrag(struct file *file)
847 {
848 	struct inode *inode = fdentry(file)->d_inode;
849 	struct btrfs_root *root = BTRFS_I(inode)->root;
850 	int ret;
851 
852 	ret = mnt_want_write(file->f_path.mnt);
853 	if (ret)
854 		return ret;
855 
856 	switch (inode->i_mode & S_IFMT) {
857 	case S_IFDIR:
858 		if (!capable(CAP_SYS_ADMIN)) {
859 			ret = -EPERM;
860 			goto out;
861 		}
862 		btrfs_defrag_root(root, 0);
863 		btrfs_defrag_root(root->fs_info->extent_root, 0);
864 		break;
865 	case S_IFREG:
866 		if (!(file->f_mode & FMODE_WRITE)) {
867 			ret = -EINVAL;
868 			goto out;
869 		}
870 		btrfs_defrag_file(file);
871 		break;
872 	}
873 out:
874 	mnt_drop_write(file->f_path.mnt);
875 	return ret;
876 }
877 
878 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
879 {
880 	struct btrfs_ioctl_vol_args *vol_args;
881 	int ret;
882 
883 	if (!capable(CAP_SYS_ADMIN))
884 		return -EPERM;
885 
886 	vol_args = memdup_user(arg, sizeof(*vol_args));
887 	if (IS_ERR(vol_args))
888 		return PTR_ERR(vol_args);
889 
890 	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
891 	ret = btrfs_init_new_device(root, vol_args->name);
892 
893 	kfree(vol_args);
894 	return ret;
895 }
896 
897 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
898 {
899 	struct btrfs_ioctl_vol_args *vol_args;
900 	int ret;
901 
902 	if (!capable(CAP_SYS_ADMIN))
903 		return -EPERM;
904 
905 	if (root->fs_info->sb->s_flags & MS_RDONLY)
906 		return -EROFS;
907 
908 	vol_args = memdup_user(arg, sizeof(*vol_args));
909 	if (IS_ERR(vol_args))
910 		return PTR_ERR(vol_args);
911 
912 	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
913 	ret = btrfs_rm_device(root, vol_args->name);
914 
915 	kfree(vol_args);
916 	return ret;
917 }
918 
919 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
920 				       u64 off, u64 olen, u64 destoff)
921 {
922 	struct inode *inode = fdentry(file)->d_inode;
923 	struct btrfs_root *root = BTRFS_I(inode)->root;
924 	struct file *src_file;
925 	struct inode *src;
926 	struct btrfs_trans_handle *trans;
927 	struct btrfs_path *path;
928 	struct extent_buffer *leaf;
929 	char *buf;
930 	struct btrfs_key key;
931 	u32 nritems;
932 	int slot;
933 	int ret;
934 	u64 len = olen;
935 	u64 bs = root->fs_info->sb->s_blocksize;
936 	u64 hint_byte;
937 
938 	/*
939 	 * TODO:
940 	 * - split compressed inline extents.  annoying: we need to
941 	 *   decompress into destination's address_space (the file offset
942 	 *   may change, so source mapping won't do), then recompress (or
943 	 *   otherwise reinsert) a subrange.
944 	 * - allow ranges within the same file to be cloned (provided
945 	 *   they don't overlap)?
946 	 */
947 
948 	/* the destination must be opened for writing */
949 	if (!(file->f_mode & FMODE_WRITE))
950 		return -EINVAL;
951 
952 	ret = mnt_want_write(file->f_path.mnt);
953 	if (ret)
954 		return ret;
955 
956 	src_file = fget(srcfd);
957 	if (!src_file) {
958 		ret = -EBADF;
959 		goto out_drop_write;
960 	}
961 	src = src_file->f_dentry->d_inode;
962 
963 	ret = -EINVAL;
964 	if (src == inode)
965 		goto out_fput;
966 
967 	ret = -EISDIR;
968 	if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
969 		goto out_fput;
970 
971 	ret = -EXDEV;
972 	if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
973 		goto out_fput;
974 
975 	ret = -ENOMEM;
976 	buf = vmalloc(btrfs_level_size(root, 0));
977 	if (!buf)
978 		goto out_fput;
979 
980 	path = btrfs_alloc_path();
981 	if (!path) {
982 		vfree(buf);
983 		goto out_fput;
984 	}
985 	path->reada = 2;
986 
987 	if (inode < src) {
988 		mutex_lock(&inode->i_mutex);
989 		mutex_lock(&src->i_mutex);
990 	} else {
991 		mutex_lock(&src->i_mutex);
992 		mutex_lock(&inode->i_mutex);
993 	}
994 
995 	/* determine range to clone */
996 	ret = -EINVAL;
997 	if (off >= src->i_size || off + len > src->i_size)
998 		goto out_unlock;
999 	if (len == 0)
1000 		olen = len = src->i_size - off;
1001 	/* if we extend to eof, continue to block boundary */
1002 	if (off + len == src->i_size)
1003 		len = ((src->i_size + bs-1) & ~(bs-1))
1004 			- off;
1005 
1006 	/* verify the end result is block aligned */
1007 	if ((off & (bs-1)) ||
1008 	    ((off + len) & (bs-1)))
1009 		goto out_unlock;
1010 
1011 	/* do any pending delalloc/csum calc on src, one way or
1012 	   another, and lock file content */
1013 	while (1) {
1014 		struct btrfs_ordered_extent *ordered;
1015 		lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
1016 		ordered = btrfs_lookup_first_ordered_extent(inode, off+len);
1017 		if (BTRFS_I(src)->delalloc_bytes == 0 && !ordered)
1018 			break;
1019 		unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
1020 		if (ordered)
1021 			btrfs_put_ordered_extent(ordered);
1022 		btrfs_wait_ordered_range(src, off, off+len);
1023 	}
1024 
1025 	trans = btrfs_start_transaction(root, 1);
1026 	BUG_ON(!trans);
1027 
1028 	/* punch hole in destination first */
1029 	btrfs_drop_extents(trans, root, inode, off, off + len,
1030 			   off + len, 0, &hint_byte, 1);
1031 
1032 	/* clone data */
1033 	key.objectid = src->i_ino;
1034 	key.type = BTRFS_EXTENT_DATA_KEY;
1035 	key.offset = 0;
1036 
1037 	while (1) {
1038 		/*
1039 		 * note the key will change type as we walk through the
1040 		 * tree.
1041 		 */
1042 		ret = btrfs_search_slot(trans, root, &key, path, 0, 0);
1043 		if (ret < 0)
1044 			goto out;
1045 
1046 		nritems = btrfs_header_nritems(path->nodes[0]);
1047 		if (path->slots[0] >= nritems) {
1048 			ret = btrfs_next_leaf(root, path);
1049 			if (ret < 0)
1050 				goto out;
1051 			if (ret > 0)
1052 				break;
1053 			nritems = btrfs_header_nritems(path->nodes[0]);
1054 		}
1055 		leaf = path->nodes[0];
1056 		slot = path->slots[0];
1057 
1058 		btrfs_item_key_to_cpu(leaf, &key, slot);
1059 		if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
1060 		    key.objectid != src->i_ino)
1061 			break;
1062 
1063 		if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
1064 			struct btrfs_file_extent_item *extent;
1065 			int type;
1066 			u32 size;
1067 			struct btrfs_key new_key;
1068 			u64 disko = 0, diskl = 0;
1069 			u64 datao = 0, datal = 0;
1070 			u8 comp;
1071 
1072 			size = btrfs_item_size_nr(leaf, slot);
1073 			read_extent_buffer(leaf, buf,
1074 					   btrfs_item_ptr_offset(leaf, slot),
1075 					   size);
1076 
1077 			extent = btrfs_item_ptr(leaf, slot,
1078 						struct btrfs_file_extent_item);
1079 			comp = btrfs_file_extent_compression(leaf, extent);
1080 			type = btrfs_file_extent_type(leaf, extent);
1081 			if (type == BTRFS_FILE_EXTENT_REG ||
1082 			    type == BTRFS_FILE_EXTENT_PREALLOC) {
1083 				disko = btrfs_file_extent_disk_bytenr(leaf,
1084 								      extent);
1085 				diskl = btrfs_file_extent_disk_num_bytes(leaf,
1086 								 extent);
1087 				datao = btrfs_file_extent_offset(leaf, extent);
1088 				datal = btrfs_file_extent_num_bytes(leaf,
1089 								    extent);
1090 			} else if (type == BTRFS_FILE_EXTENT_INLINE) {
1091 				/* take upper bound, may be compressed */
1092 				datal = btrfs_file_extent_ram_bytes(leaf,
1093 								    extent);
1094 			}
1095 			btrfs_release_path(root, path);
1096 
1097 			if (key.offset + datal < off ||
1098 			    key.offset >= off+len)
1099 				goto next;
1100 
1101 			memcpy(&new_key, &key, sizeof(new_key));
1102 			new_key.objectid = inode->i_ino;
1103 			new_key.offset = key.offset + destoff - off;
1104 
1105 			if (type == BTRFS_FILE_EXTENT_REG ||
1106 			    type == BTRFS_FILE_EXTENT_PREALLOC) {
1107 				ret = btrfs_insert_empty_item(trans, root, path,
1108 							      &new_key, size);
1109 				if (ret)
1110 					goto out;
1111 
1112 				leaf = path->nodes[0];
1113 				slot = path->slots[0];
1114 				write_extent_buffer(leaf, buf,
1115 					    btrfs_item_ptr_offset(leaf, slot),
1116 					    size);
1117 
1118 				extent = btrfs_item_ptr(leaf, slot,
1119 						struct btrfs_file_extent_item);
1120 
1121 				if (off > key.offset) {
1122 					datao += off - key.offset;
1123 					datal -= off - key.offset;
1124 				}
1125 				if (key.offset + datao + datal > off + len)
1126 					datal = off + len - key.offset - datao;
1127 				/* disko == 0 means it's a hole */
1128 				if (!disko)
1129 					datao = 0;
1130 
1131 				btrfs_set_file_extent_offset(leaf, extent,
1132 							     datao);
1133 				btrfs_set_file_extent_num_bytes(leaf, extent,
1134 								datal);
1135 				if (disko) {
1136 					inode_add_bytes(inode, datal);
1137 					ret = btrfs_inc_extent_ref(trans, root,
1138 							disko, diskl, 0,
1139 							root->root_key.objectid,
1140 							inode->i_ino,
1141 							new_key.offset - datao);
1142 					BUG_ON(ret);
1143 				}
1144 			} else if (type == BTRFS_FILE_EXTENT_INLINE) {
1145 				u64 skip = 0;
1146 				u64 trim = 0;
1147 				if (off > key.offset) {
1148 					skip = off - key.offset;
1149 					new_key.offset += skip;
1150 				}
1151 
1152 				if (key.offset + datal > off+len)
1153 					trim = key.offset + datal - (off+len);
1154 
1155 				if (comp && (skip || trim)) {
1156 					ret = -EINVAL;
1157 					goto out;
1158 				}
1159 				size -= skip + trim;
1160 				datal -= skip + trim;
1161 				ret = btrfs_insert_empty_item(trans, root, path,
1162 							      &new_key, size);
1163 				if (ret)
1164 					goto out;
1165 
1166 				if (skip) {
1167 					u32 start =
1168 					  btrfs_file_extent_calc_inline_size(0);
1169 					memmove(buf+start, buf+start+skip,
1170 						datal);
1171 				}
1172 
1173 				leaf = path->nodes[0];
1174 				slot = path->slots[0];
1175 				write_extent_buffer(leaf, buf,
1176 					    btrfs_item_ptr_offset(leaf, slot),
1177 					    size);
1178 				inode_add_bytes(inode, datal);
1179 			}
1180 
1181 			btrfs_mark_buffer_dirty(leaf);
1182 		}
1183 
1184 next:
1185 		btrfs_release_path(root, path);
1186 		key.offset++;
1187 	}
1188 	ret = 0;
1189 out:
1190 	btrfs_release_path(root, path);
1191 	if (ret == 0) {
1192 		inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1193 		if (destoff + olen > inode->i_size)
1194 			btrfs_i_size_write(inode, destoff + olen);
1195 		BTRFS_I(inode)->flags = BTRFS_I(src)->flags;
1196 		ret = btrfs_update_inode(trans, root, inode);
1197 	}
1198 	btrfs_end_transaction(trans, root);
1199 	unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
1200 	if (ret)
1201 		vmtruncate(inode, 0);
1202 out_unlock:
1203 	mutex_unlock(&src->i_mutex);
1204 	mutex_unlock(&inode->i_mutex);
1205 	vfree(buf);
1206 	btrfs_free_path(path);
1207 out_fput:
1208 	fput(src_file);
1209 out_drop_write:
1210 	mnt_drop_write(file->f_path.mnt);
1211 	return ret;
1212 }
1213 
1214 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
1215 {
1216 	struct btrfs_ioctl_clone_range_args args;
1217 
1218 	if (copy_from_user(&args, argp, sizeof(args)))
1219 		return -EFAULT;
1220 	return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
1221 				 args.src_length, args.dest_offset);
1222 }
1223 
1224 /*
1225  * there are many ways the trans_start and trans_end ioctls can lead
1226  * to deadlocks.  They should only be used by applications that
1227  * basically own the machine, and have a very in depth understanding
1228  * of all the possible deadlocks and enospc problems.
1229  */
1230 static long btrfs_ioctl_trans_start(struct file *file)
1231 {
1232 	struct inode *inode = fdentry(file)->d_inode;
1233 	struct btrfs_root *root = BTRFS_I(inode)->root;
1234 	struct btrfs_trans_handle *trans;
1235 	int ret;
1236 
1237 	ret = -EPERM;
1238 	if (!capable(CAP_SYS_ADMIN))
1239 		goto out;
1240 
1241 	ret = -EINPROGRESS;
1242 	if (file->private_data)
1243 		goto out;
1244 
1245 	ret = mnt_want_write(file->f_path.mnt);
1246 	if (ret)
1247 		goto out;
1248 
1249 	mutex_lock(&root->fs_info->trans_mutex);
1250 	root->fs_info->open_ioctl_trans++;
1251 	mutex_unlock(&root->fs_info->trans_mutex);
1252 
1253 	ret = -ENOMEM;
1254 	trans = btrfs_start_ioctl_transaction(root, 0);
1255 	if (!trans)
1256 		goto out_drop;
1257 
1258 	file->private_data = trans;
1259 	return 0;
1260 
1261 out_drop:
1262 	mutex_lock(&root->fs_info->trans_mutex);
1263 	root->fs_info->open_ioctl_trans--;
1264 	mutex_unlock(&root->fs_info->trans_mutex);
1265 	mnt_drop_write(file->f_path.mnt);
1266 out:
1267 	return ret;
1268 }
1269 
1270 /*
1271  * there are many ways the trans_start and trans_end ioctls can lead
1272  * to deadlocks.  They should only be used by applications that
1273  * basically own the machine, and have a very in depth understanding
1274  * of all the possible deadlocks and enospc problems.
1275  */
1276 long btrfs_ioctl_trans_end(struct file *file)
1277 {
1278 	struct inode *inode = fdentry(file)->d_inode;
1279 	struct btrfs_root *root = BTRFS_I(inode)->root;
1280 	struct btrfs_trans_handle *trans;
1281 
1282 	trans = file->private_data;
1283 	if (!trans)
1284 		return -EINVAL;
1285 	file->private_data = NULL;
1286 
1287 	btrfs_end_transaction(trans, root);
1288 
1289 	mutex_lock(&root->fs_info->trans_mutex);
1290 	root->fs_info->open_ioctl_trans--;
1291 	mutex_unlock(&root->fs_info->trans_mutex);
1292 
1293 	mnt_drop_write(file->f_path.mnt);
1294 	return 0;
1295 }
1296 
1297 long btrfs_ioctl(struct file *file, unsigned int
1298 		cmd, unsigned long arg)
1299 {
1300 	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1301 	void __user *argp = (void __user *)arg;
1302 
1303 	switch (cmd) {
1304 	case FS_IOC_GETFLAGS:
1305 		return btrfs_ioctl_getflags(file, argp);
1306 	case FS_IOC_SETFLAGS:
1307 		return btrfs_ioctl_setflags(file, argp);
1308 	case FS_IOC_GETVERSION:
1309 		return btrfs_ioctl_getversion(file, argp);
1310 	case BTRFS_IOC_SNAP_CREATE:
1311 		return btrfs_ioctl_snap_create(file, argp, 0);
1312 	case BTRFS_IOC_SUBVOL_CREATE:
1313 		return btrfs_ioctl_snap_create(file, argp, 1);
1314 	case BTRFS_IOC_SNAP_DESTROY:
1315 		return btrfs_ioctl_snap_destroy(file, argp);
1316 	case BTRFS_IOC_DEFRAG:
1317 		return btrfs_ioctl_defrag(file);
1318 	case BTRFS_IOC_RESIZE:
1319 		return btrfs_ioctl_resize(root, argp);
1320 	case BTRFS_IOC_ADD_DEV:
1321 		return btrfs_ioctl_add_dev(root, argp);
1322 	case BTRFS_IOC_RM_DEV:
1323 		return btrfs_ioctl_rm_dev(root, argp);
1324 	case BTRFS_IOC_BALANCE:
1325 		return btrfs_balance(root->fs_info->dev_root);
1326 	case BTRFS_IOC_CLONE:
1327 		return btrfs_ioctl_clone(file, arg, 0, 0, 0);
1328 	case BTRFS_IOC_CLONE_RANGE:
1329 		return btrfs_ioctl_clone_range(file, argp);
1330 	case BTRFS_IOC_TRANS_START:
1331 		return btrfs_ioctl_trans_start(file);
1332 	case BTRFS_IOC_TRANS_END:
1333 		return btrfs_ioctl_trans_end(file);
1334 	case BTRFS_IOC_SYNC:
1335 		btrfs_sync_fs(file->f_dentry->d_sb, 1);
1336 		return 0;
1337 	}
1338 
1339 	return -ENOTTY;
1340 }
1341