Btrfs: rename btrfs_sysfs_remove_one to btrfs_sysfs_remove_mounted
[linux/fpc-iii.git] / fs / btrfs / ioctl.c
blob0adf5422fce9d4b9fc62c2bbf319429b38aaec7c
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
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.
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.
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.
19 #include <linux/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.h>
23 #include <linux/fs.h>
24 #include <linux/fsnotify.h>
25 #include <linux/pagemap.h>
26 #include <linux/highmem.h>
27 #include <linux/time.h>
28 #include <linux/init.h>
29 #include <linux/string.h>
30 #include <linux/backing-dev.h>
31 #include <linux/mount.h>
32 #include <linux/mpage.h>
33 #include <linux/namei.h>
34 #include <linux/swap.h>
35 #include <linux/writeback.h>
36 #include <linux/statfs.h>
37 #include <linux/compat.h>
38 #include <linux/bit_spinlock.h>
39 #include <linux/security.h>
40 #include <linux/xattr.h>
41 #include <linux/vmalloc.h>
42 #include <linux/slab.h>
43 #include <linux/blkdev.h>
44 #include <linux/uuid.h>
45 #include <linux/btrfs.h>
46 #include <linux/uaccess.h>
47 #include "ctree.h"
48 #include "disk-io.h"
49 #include "transaction.h"
50 #include "btrfs_inode.h"
51 #include "print-tree.h"
52 #include "volumes.h"
53 #include "locking.h"
54 #include "inode-map.h"
55 #include "backref.h"
56 #include "rcu-string.h"
57 #include "send.h"
58 #include "dev-replace.h"
59 #include "props.h"
60 #include "sysfs.h"
61 #include "qgroup.h"
63 #ifdef CONFIG_64BIT
64 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
65 * structures are incorrect, as the timespec structure from userspace
66 * is 4 bytes too small. We define these alternatives here to teach
67 * the kernel about the 32-bit struct packing.
69 struct btrfs_ioctl_timespec_32 {
70 __u64 sec;
71 __u32 nsec;
72 } __attribute__ ((__packed__));
74 struct btrfs_ioctl_received_subvol_args_32 {
75 char uuid[BTRFS_UUID_SIZE]; /* in */
76 __u64 stransid; /* in */
77 __u64 rtransid; /* out */
78 struct btrfs_ioctl_timespec_32 stime; /* in */
79 struct btrfs_ioctl_timespec_32 rtime; /* out */
80 __u64 flags; /* in */
81 __u64 reserved[16]; /* in */
82 } __attribute__ ((__packed__));
84 #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
85 struct btrfs_ioctl_received_subvol_args_32)
86 #endif
89 static int btrfs_clone(struct inode *src, struct inode *inode,
90 u64 off, u64 olen, u64 olen_aligned, u64 destoff,
91 int no_time_update);
93 /* Mask out flags that are inappropriate for the given type of inode. */
94 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
96 if (S_ISDIR(mode))
97 return flags;
98 else if (S_ISREG(mode))
99 return flags & ~FS_DIRSYNC_FL;
100 else
101 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
105 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
107 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
109 unsigned int iflags = 0;
111 if (flags & BTRFS_INODE_SYNC)
112 iflags |= FS_SYNC_FL;
113 if (flags & BTRFS_INODE_IMMUTABLE)
114 iflags |= FS_IMMUTABLE_FL;
115 if (flags & BTRFS_INODE_APPEND)
116 iflags |= FS_APPEND_FL;
117 if (flags & BTRFS_INODE_NODUMP)
118 iflags |= FS_NODUMP_FL;
119 if (flags & BTRFS_INODE_NOATIME)
120 iflags |= FS_NOATIME_FL;
121 if (flags & BTRFS_INODE_DIRSYNC)
122 iflags |= FS_DIRSYNC_FL;
123 if (flags & BTRFS_INODE_NODATACOW)
124 iflags |= FS_NOCOW_FL;
126 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
127 iflags |= FS_COMPR_FL;
128 else if (flags & BTRFS_INODE_NOCOMPRESS)
129 iflags |= FS_NOCOMP_FL;
131 return iflags;
135 * Update inode->i_flags based on the btrfs internal flags.
137 void btrfs_update_iflags(struct inode *inode)
139 struct btrfs_inode *ip = BTRFS_I(inode);
140 unsigned int new_fl = 0;
142 if (ip->flags & BTRFS_INODE_SYNC)
143 new_fl |= S_SYNC;
144 if (ip->flags & BTRFS_INODE_IMMUTABLE)
145 new_fl |= S_IMMUTABLE;
146 if (ip->flags & BTRFS_INODE_APPEND)
147 new_fl |= S_APPEND;
148 if (ip->flags & BTRFS_INODE_NOATIME)
149 new_fl |= S_NOATIME;
150 if (ip->flags & BTRFS_INODE_DIRSYNC)
151 new_fl |= S_DIRSYNC;
153 set_mask_bits(&inode->i_flags,
154 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
155 new_fl);
159 * Inherit flags from the parent inode.
161 * Currently only the compression flags and the cow flags are inherited.
163 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
165 unsigned int flags;
167 if (!dir)
168 return;
170 flags = BTRFS_I(dir)->flags;
172 if (flags & BTRFS_INODE_NOCOMPRESS) {
173 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
174 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
175 } else if (flags & BTRFS_INODE_COMPRESS) {
176 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
177 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
180 if (flags & BTRFS_INODE_NODATACOW) {
181 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
182 if (S_ISREG(inode->i_mode))
183 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
186 btrfs_update_iflags(inode);
189 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
191 struct btrfs_inode *ip = BTRFS_I(file_inode(file));
192 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
194 if (copy_to_user(arg, &flags, sizeof(flags)))
195 return -EFAULT;
196 return 0;
199 static int check_flags(unsigned int flags)
201 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
202 FS_NOATIME_FL | FS_NODUMP_FL | \
203 FS_SYNC_FL | FS_DIRSYNC_FL | \
204 FS_NOCOMP_FL | FS_COMPR_FL |
205 FS_NOCOW_FL))
206 return -EOPNOTSUPP;
208 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
209 return -EINVAL;
211 return 0;
214 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
216 struct inode *inode = file_inode(file);
217 struct btrfs_inode *ip = BTRFS_I(inode);
218 struct btrfs_root *root = ip->root;
219 struct btrfs_trans_handle *trans;
220 unsigned int flags, oldflags;
221 int ret;
222 u64 ip_oldflags;
223 unsigned int i_oldflags;
224 umode_t mode;
226 if (!inode_owner_or_capable(inode))
227 return -EPERM;
229 if (btrfs_root_readonly(root))
230 return -EROFS;
232 if (copy_from_user(&flags, arg, sizeof(flags)))
233 return -EFAULT;
235 ret = check_flags(flags);
236 if (ret)
237 return ret;
239 ret = mnt_want_write_file(file);
240 if (ret)
241 return ret;
243 mutex_lock(&inode->i_mutex);
245 ip_oldflags = ip->flags;
246 i_oldflags = inode->i_flags;
247 mode = inode->i_mode;
249 flags = btrfs_mask_flags(inode->i_mode, flags);
250 oldflags = btrfs_flags_to_ioctl(ip->flags);
251 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
252 if (!capable(CAP_LINUX_IMMUTABLE)) {
253 ret = -EPERM;
254 goto out_unlock;
258 if (flags & FS_SYNC_FL)
259 ip->flags |= BTRFS_INODE_SYNC;
260 else
261 ip->flags &= ~BTRFS_INODE_SYNC;
262 if (flags & FS_IMMUTABLE_FL)
263 ip->flags |= BTRFS_INODE_IMMUTABLE;
264 else
265 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
266 if (flags & FS_APPEND_FL)
267 ip->flags |= BTRFS_INODE_APPEND;
268 else
269 ip->flags &= ~BTRFS_INODE_APPEND;
270 if (flags & FS_NODUMP_FL)
271 ip->flags |= BTRFS_INODE_NODUMP;
272 else
273 ip->flags &= ~BTRFS_INODE_NODUMP;
274 if (flags & FS_NOATIME_FL)
275 ip->flags |= BTRFS_INODE_NOATIME;
276 else
277 ip->flags &= ~BTRFS_INODE_NOATIME;
278 if (flags & FS_DIRSYNC_FL)
279 ip->flags |= BTRFS_INODE_DIRSYNC;
280 else
281 ip->flags &= ~BTRFS_INODE_DIRSYNC;
282 if (flags & FS_NOCOW_FL) {
283 if (S_ISREG(mode)) {
285 * It's safe to turn csums off here, no extents exist.
286 * Otherwise we want the flag to reflect the real COW
287 * status of the file and will not set it.
289 if (inode->i_size == 0)
290 ip->flags |= BTRFS_INODE_NODATACOW
291 | BTRFS_INODE_NODATASUM;
292 } else {
293 ip->flags |= BTRFS_INODE_NODATACOW;
295 } else {
297 * Revert back under same assuptions as above
299 if (S_ISREG(mode)) {
300 if (inode->i_size == 0)
301 ip->flags &= ~(BTRFS_INODE_NODATACOW
302 | BTRFS_INODE_NODATASUM);
303 } else {
304 ip->flags &= ~BTRFS_INODE_NODATACOW;
309 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
310 * flag may be changed automatically if compression code won't make
311 * things smaller.
313 if (flags & FS_NOCOMP_FL) {
314 ip->flags &= ~BTRFS_INODE_COMPRESS;
315 ip->flags |= BTRFS_INODE_NOCOMPRESS;
317 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
318 if (ret && ret != -ENODATA)
319 goto out_drop;
320 } else if (flags & FS_COMPR_FL) {
321 const char *comp;
323 ip->flags |= BTRFS_INODE_COMPRESS;
324 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
326 if (root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
327 comp = "lzo";
328 else
329 comp = "zlib";
330 ret = btrfs_set_prop(inode, "btrfs.compression",
331 comp, strlen(comp), 0);
332 if (ret)
333 goto out_drop;
335 } else {
336 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
337 if (ret && ret != -ENODATA)
338 goto out_drop;
339 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
342 trans = btrfs_start_transaction(root, 1);
343 if (IS_ERR(trans)) {
344 ret = PTR_ERR(trans);
345 goto out_drop;
348 btrfs_update_iflags(inode);
349 inode_inc_iversion(inode);
350 inode->i_ctime = CURRENT_TIME;
351 ret = btrfs_update_inode(trans, root, inode);
353 btrfs_end_transaction(trans, root);
354 out_drop:
355 if (ret) {
356 ip->flags = ip_oldflags;
357 inode->i_flags = i_oldflags;
360 out_unlock:
361 mutex_unlock(&inode->i_mutex);
362 mnt_drop_write_file(file);
363 return ret;
366 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
368 struct inode *inode = file_inode(file);
370 return put_user(inode->i_generation, arg);
373 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
375 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
376 struct btrfs_device *device;
377 struct request_queue *q;
378 struct fstrim_range range;
379 u64 minlen = ULLONG_MAX;
380 u64 num_devices = 0;
381 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
382 int ret;
384 if (!capable(CAP_SYS_ADMIN))
385 return -EPERM;
387 rcu_read_lock();
388 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
389 dev_list) {
390 if (!device->bdev)
391 continue;
392 q = bdev_get_queue(device->bdev);
393 if (blk_queue_discard(q)) {
394 num_devices++;
395 minlen = min((u64)q->limits.discard_granularity,
396 minlen);
399 rcu_read_unlock();
401 if (!num_devices)
402 return -EOPNOTSUPP;
403 if (copy_from_user(&range, arg, sizeof(range)))
404 return -EFAULT;
405 if (range.start > total_bytes ||
406 range.len < fs_info->sb->s_blocksize)
407 return -EINVAL;
409 range.len = min(range.len, total_bytes - range.start);
410 range.minlen = max(range.minlen, minlen);
411 ret = btrfs_trim_fs(fs_info->tree_root, &range);
412 if (ret < 0)
413 return ret;
415 if (copy_to_user(arg, &range, sizeof(range)))
416 return -EFAULT;
418 return 0;
421 int btrfs_is_empty_uuid(u8 *uuid)
423 int i;
425 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
426 if (uuid[i])
427 return 0;
429 return 1;
432 static noinline int create_subvol(struct inode *dir,
433 struct dentry *dentry,
434 char *name, int namelen,
435 u64 *async_transid,
436 struct btrfs_qgroup_inherit *inherit)
438 struct btrfs_trans_handle *trans;
439 struct btrfs_key key;
440 struct btrfs_root_item root_item;
441 struct btrfs_inode_item *inode_item;
442 struct extent_buffer *leaf;
443 struct btrfs_root *root = BTRFS_I(dir)->root;
444 struct btrfs_root *new_root;
445 struct btrfs_block_rsv block_rsv;
446 struct timespec cur_time = CURRENT_TIME;
447 struct inode *inode;
448 int ret;
449 int err;
450 u64 objectid;
451 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
452 u64 index = 0;
453 u64 qgroup_reserved;
454 uuid_le new_uuid;
456 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
457 if (ret)
458 return ret;
461 * Don't create subvolume whose level is not zero. Or qgroup will be
462 * screwed up since it assume subvolme qgroup's level to be 0.
464 if (btrfs_qgroup_level(objectid))
465 return -ENOSPC;
467 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
469 * The same as the snapshot creation, please see the comment
470 * of create_snapshot().
472 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
473 8, &qgroup_reserved, false);
474 if (ret)
475 return ret;
477 trans = btrfs_start_transaction(root, 0);
478 if (IS_ERR(trans)) {
479 ret = PTR_ERR(trans);
480 btrfs_subvolume_release_metadata(root, &block_rsv,
481 qgroup_reserved);
482 return ret;
484 trans->block_rsv = &block_rsv;
485 trans->bytes_reserved = block_rsv.size;
487 ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
488 if (ret)
489 goto fail;
491 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
492 if (IS_ERR(leaf)) {
493 ret = PTR_ERR(leaf);
494 goto fail;
497 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
498 btrfs_set_header_bytenr(leaf, leaf->start);
499 btrfs_set_header_generation(leaf, trans->transid);
500 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
501 btrfs_set_header_owner(leaf, objectid);
503 write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(),
504 BTRFS_FSID_SIZE);
505 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
506 btrfs_header_chunk_tree_uuid(leaf),
507 BTRFS_UUID_SIZE);
508 btrfs_mark_buffer_dirty(leaf);
510 memset(&root_item, 0, sizeof(root_item));
512 inode_item = &root_item.inode;
513 btrfs_set_stack_inode_generation(inode_item, 1);
514 btrfs_set_stack_inode_size(inode_item, 3);
515 btrfs_set_stack_inode_nlink(inode_item, 1);
516 btrfs_set_stack_inode_nbytes(inode_item, root->nodesize);
517 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
519 btrfs_set_root_flags(&root_item, 0);
520 btrfs_set_root_limit(&root_item, 0);
521 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
523 btrfs_set_root_bytenr(&root_item, leaf->start);
524 btrfs_set_root_generation(&root_item, trans->transid);
525 btrfs_set_root_level(&root_item, 0);
526 btrfs_set_root_refs(&root_item, 1);
527 btrfs_set_root_used(&root_item, leaf->len);
528 btrfs_set_root_last_snapshot(&root_item, 0);
530 btrfs_set_root_generation_v2(&root_item,
531 btrfs_root_generation(&root_item));
532 uuid_le_gen(&new_uuid);
533 memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
534 btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
535 btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec);
536 root_item.ctime = root_item.otime;
537 btrfs_set_root_ctransid(&root_item, trans->transid);
538 btrfs_set_root_otransid(&root_item, trans->transid);
540 btrfs_tree_unlock(leaf);
541 free_extent_buffer(leaf);
542 leaf = NULL;
544 btrfs_set_root_dirid(&root_item, new_dirid);
546 key.objectid = objectid;
547 key.offset = 0;
548 key.type = BTRFS_ROOT_ITEM_KEY;
549 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
550 &root_item);
551 if (ret)
552 goto fail;
554 key.offset = (u64)-1;
555 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
556 if (IS_ERR(new_root)) {
557 ret = PTR_ERR(new_root);
558 btrfs_abort_transaction(trans, root, ret);
559 goto fail;
562 btrfs_record_root_in_trans(trans, new_root);
564 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
565 if (ret) {
566 /* We potentially lose an unused inode item here */
567 btrfs_abort_transaction(trans, root, ret);
568 goto fail;
572 * insert the directory item
574 ret = btrfs_set_inode_index(dir, &index);
575 if (ret) {
576 btrfs_abort_transaction(trans, root, ret);
577 goto fail;
580 ret = btrfs_insert_dir_item(trans, root,
581 name, namelen, dir, &key,
582 BTRFS_FT_DIR, index);
583 if (ret) {
584 btrfs_abort_transaction(trans, root, ret);
585 goto fail;
588 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
589 ret = btrfs_update_inode(trans, root, dir);
590 BUG_ON(ret);
592 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
593 objectid, root->root_key.objectid,
594 btrfs_ino(dir), index, name, namelen);
595 BUG_ON(ret);
597 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
598 root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
599 objectid);
600 if (ret)
601 btrfs_abort_transaction(trans, root, ret);
603 fail:
604 trans->block_rsv = NULL;
605 trans->bytes_reserved = 0;
606 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
608 if (async_transid) {
609 *async_transid = trans->transid;
610 err = btrfs_commit_transaction_async(trans, root, 1);
611 if (err)
612 err = btrfs_commit_transaction(trans, root);
613 } else {
614 err = btrfs_commit_transaction(trans, root);
616 if (err && !ret)
617 ret = err;
619 if (!ret) {
620 inode = btrfs_lookup_dentry(dir, dentry);
621 if (IS_ERR(inode))
622 return PTR_ERR(inode);
623 d_instantiate(dentry, inode);
625 return ret;
628 static void btrfs_wait_for_no_snapshoting_writes(struct btrfs_root *root)
630 s64 writers;
631 DEFINE_WAIT(wait);
633 do {
634 prepare_to_wait(&root->subv_writers->wait, &wait,
635 TASK_UNINTERRUPTIBLE);
637 writers = percpu_counter_sum(&root->subv_writers->counter);
638 if (writers)
639 schedule();
641 finish_wait(&root->subv_writers->wait, &wait);
642 } while (writers);
645 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
646 struct dentry *dentry, char *name, int namelen,
647 u64 *async_transid, bool readonly,
648 struct btrfs_qgroup_inherit *inherit)
650 struct inode *inode;
651 struct btrfs_pending_snapshot *pending_snapshot;
652 struct btrfs_trans_handle *trans;
653 int ret;
655 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
656 return -EINVAL;
658 atomic_inc(&root->will_be_snapshoted);
659 smp_mb__after_atomic();
660 btrfs_wait_for_no_snapshoting_writes(root);
662 ret = btrfs_start_delalloc_inodes(root, 0);
663 if (ret)
664 goto out;
666 btrfs_wait_ordered_extents(root, -1);
668 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
669 if (!pending_snapshot) {
670 ret = -ENOMEM;
671 goto out;
674 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
675 BTRFS_BLOCK_RSV_TEMP);
677 * 1 - parent dir inode
678 * 2 - dir entries
679 * 1 - root item
680 * 2 - root ref/backref
681 * 1 - root of snapshot
682 * 1 - UUID item
684 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
685 &pending_snapshot->block_rsv, 8,
686 &pending_snapshot->qgroup_reserved,
687 false);
688 if (ret)
689 goto free;
691 pending_snapshot->dentry = dentry;
692 pending_snapshot->root = root;
693 pending_snapshot->readonly = readonly;
694 pending_snapshot->dir = dir;
695 pending_snapshot->inherit = inherit;
697 trans = btrfs_start_transaction(root, 0);
698 if (IS_ERR(trans)) {
699 ret = PTR_ERR(trans);
700 goto fail;
703 spin_lock(&root->fs_info->trans_lock);
704 list_add(&pending_snapshot->list,
705 &trans->transaction->pending_snapshots);
706 spin_unlock(&root->fs_info->trans_lock);
707 if (async_transid) {
708 *async_transid = trans->transid;
709 ret = btrfs_commit_transaction_async(trans,
710 root->fs_info->extent_root, 1);
711 if (ret)
712 ret = btrfs_commit_transaction(trans, root);
713 } else {
714 ret = btrfs_commit_transaction(trans,
715 root->fs_info->extent_root);
717 if (ret)
718 goto fail;
720 ret = pending_snapshot->error;
721 if (ret)
722 goto fail;
724 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
725 if (ret)
726 goto fail;
728 inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
729 if (IS_ERR(inode)) {
730 ret = PTR_ERR(inode);
731 goto fail;
734 d_instantiate(dentry, inode);
735 ret = 0;
736 fail:
737 btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
738 &pending_snapshot->block_rsv,
739 pending_snapshot->qgroup_reserved);
740 free:
741 kfree(pending_snapshot);
742 out:
743 if (atomic_dec_and_test(&root->will_be_snapshoted))
744 wake_up_atomic_t(&root->will_be_snapshoted);
745 return ret;
748 /* copy of may_delete in fs/namei.c()
749 * Check whether we can remove a link victim from directory dir, check
750 * whether the type of victim is right.
751 * 1. We can't do it if dir is read-only (done in permission())
752 * 2. We should have write and exec permissions on dir
753 * 3. We can't remove anything from append-only dir
754 * 4. We can't do anything with immutable dir (done in permission())
755 * 5. If the sticky bit on dir is set we should either
756 * a. be owner of dir, or
757 * b. be owner of victim, or
758 * c. have CAP_FOWNER capability
759 * 6. If the victim is append-only or immutable we can't do antyhing with
760 * links pointing to it.
761 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
762 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
763 * 9. We can't remove a root or mountpoint.
764 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
765 * nfs_async_unlink().
768 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
770 int error;
772 if (d_really_is_negative(victim))
773 return -ENOENT;
775 BUG_ON(d_inode(victim->d_parent) != dir);
776 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
778 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
779 if (error)
780 return error;
781 if (IS_APPEND(dir))
782 return -EPERM;
783 if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
784 IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
785 return -EPERM;
786 if (isdir) {
787 if (!d_is_dir(victim))
788 return -ENOTDIR;
789 if (IS_ROOT(victim))
790 return -EBUSY;
791 } else if (d_is_dir(victim))
792 return -EISDIR;
793 if (IS_DEADDIR(dir))
794 return -ENOENT;
795 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
796 return -EBUSY;
797 return 0;
800 /* copy of may_create in fs/namei.c() */
801 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
803 if (d_really_is_positive(child))
804 return -EEXIST;
805 if (IS_DEADDIR(dir))
806 return -ENOENT;
807 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
811 * Create a new subvolume below @parent. This is largely modeled after
812 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
813 * inside this filesystem so it's quite a bit simpler.
815 static noinline int btrfs_mksubvol(struct path *parent,
816 char *name, int namelen,
817 struct btrfs_root *snap_src,
818 u64 *async_transid, bool readonly,
819 struct btrfs_qgroup_inherit *inherit)
821 struct inode *dir = d_inode(parent->dentry);
822 struct dentry *dentry;
823 int error;
825 error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
826 if (error == -EINTR)
827 return error;
829 dentry = lookup_one_len(name, parent->dentry, namelen);
830 error = PTR_ERR(dentry);
831 if (IS_ERR(dentry))
832 goto out_unlock;
834 error = -EEXIST;
835 if (d_really_is_positive(dentry))
836 goto out_dput;
838 error = btrfs_may_create(dir, dentry);
839 if (error)
840 goto out_dput;
843 * even if this name doesn't exist, we may get hash collisions.
844 * check for them now when we can safely fail
846 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
847 dir->i_ino, name,
848 namelen);
849 if (error)
850 goto out_dput;
852 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
854 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
855 goto out_up_read;
857 if (snap_src) {
858 error = create_snapshot(snap_src, dir, dentry, name, namelen,
859 async_transid, readonly, inherit);
860 } else {
861 error = create_subvol(dir, dentry, name, namelen,
862 async_transid, inherit);
864 if (!error)
865 fsnotify_mkdir(dir, dentry);
866 out_up_read:
867 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
868 out_dput:
869 dput(dentry);
870 out_unlock:
871 mutex_unlock(&dir->i_mutex);
872 return error;
876 * When we're defragging a range, we don't want to kick it off again
877 * if it is really just waiting for delalloc to send it down.
878 * If we find a nice big extent or delalloc range for the bytes in the
879 * file you want to defrag, we return 0 to let you know to skip this
880 * part of the file
882 static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
884 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
885 struct extent_map *em = NULL;
886 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
887 u64 end;
889 read_lock(&em_tree->lock);
890 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
891 read_unlock(&em_tree->lock);
893 if (em) {
894 end = extent_map_end(em);
895 free_extent_map(em);
896 if (end - offset > thresh)
897 return 0;
899 /* if we already have a nice delalloc here, just stop */
900 thresh /= 2;
901 end = count_range_bits(io_tree, &offset, offset + thresh,
902 thresh, EXTENT_DELALLOC, 1);
903 if (end >= thresh)
904 return 0;
905 return 1;
909 * helper function to walk through a file and find extents
910 * newer than a specific transid, and smaller than thresh.
912 * This is used by the defragging code to find new and small
913 * extents
915 static int find_new_extents(struct btrfs_root *root,
916 struct inode *inode, u64 newer_than,
917 u64 *off, u32 thresh)
919 struct btrfs_path *path;
920 struct btrfs_key min_key;
921 struct extent_buffer *leaf;
922 struct btrfs_file_extent_item *extent;
923 int type;
924 int ret;
925 u64 ino = btrfs_ino(inode);
927 path = btrfs_alloc_path();
928 if (!path)
929 return -ENOMEM;
931 min_key.objectid = ino;
932 min_key.type = BTRFS_EXTENT_DATA_KEY;
933 min_key.offset = *off;
935 while (1) {
936 ret = btrfs_search_forward(root, &min_key, path, newer_than);
937 if (ret != 0)
938 goto none;
939 process_slot:
940 if (min_key.objectid != ino)
941 goto none;
942 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
943 goto none;
945 leaf = path->nodes[0];
946 extent = btrfs_item_ptr(leaf, path->slots[0],
947 struct btrfs_file_extent_item);
949 type = btrfs_file_extent_type(leaf, extent);
950 if (type == BTRFS_FILE_EXTENT_REG &&
951 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
952 check_defrag_in_cache(inode, min_key.offset, thresh)) {
953 *off = min_key.offset;
954 btrfs_free_path(path);
955 return 0;
958 path->slots[0]++;
959 if (path->slots[0] < btrfs_header_nritems(leaf)) {
960 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
961 goto process_slot;
964 if (min_key.offset == (u64)-1)
965 goto none;
967 min_key.offset++;
968 btrfs_release_path(path);
970 none:
971 btrfs_free_path(path);
972 return -ENOENT;
975 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
977 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
978 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
979 struct extent_map *em;
980 u64 len = PAGE_CACHE_SIZE;
983 * hopefully we have this extent in the tree already, try without
984 * the full extent lock
986 read_lock(&em_tree->lock);
987 em = lookup_extent_mapping(em_tree, start, len);
988 read_unlock(&em_tree->lock);
990 if (!em) {
991 struct extent_state *cached = NULL;
992 u64 end = start + len - 1;
994 /* get the big lock and read metadata off disk */
995 lock_extent_bits(io_tree, start, end, 0, &cached);
996 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
997 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
999 if (IS_ERR(em))
1000 return NULL;
1003 return em;
1006 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1008 struct extent_map *next;
1009 bool ret = true;
1011 /* this is the last extent */
1012 if (em->start + em->len >= i_size_read(inode))
1013 return false;
1015 next = defrag_lookup_extent(inode, em->start + em->len);
1016 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1017 ret = false;
1018 else if ((em->block_start + em->block_len == next->block_start) &&
1019 (em->block_len > 128 * 1024 && next->block_len > 128 * 1024))
1020 ret = false;
1022 free_extent_map(next);
1023 return ret;
1026 static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1027 u64 *last_len, u64 *skip, u64 *defrag_end,
1028 int compress)
1030 struct extent_map *em;
1031 int ret = 1;
1032 bool next_mergeable = true;
1033 bool prev_mergeable = true;
1036 * make sure that once we start defragging an extent, we keep on
1037 * defragging it
1039 if (start < *defrag_end)
1040 return 1;
1042 *skip = 0;
1044 em = defrag_lookup_extent(inode, start);
1045 if (!em)
1046 return 0;
1048 /* this will cover holes, and inline extents */
1049 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1050 ret = 0;
1051 goto out;
1054 if (!*defrag_end)
1055 prev_mergeable = false;
1057 next_mergeable = defrag_check_next_extent(inode, em);
1059 * we hit a real extent, if it is big or the next extent is not a
1060 * real extent, don't bother defragging it
1062 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1063 (em->len >= thresh || (!next_mergeable && !prev_mergeable)))
1064 ret = 0;
1065 out:
1067 * last_len ends up being a counter of how many bytes we've defragged.
1068 * every time we choose not to defrag an extent, we reset *last_len
1069 * so that the next tiny extent will force a defrag.
1071 * The end result of this is that tiny extents before a single big
1072 * extent will force at least part of that big extent to be defragged.
1074 if (ret) {
1075 *defrag_end = extent_map_end(em);
1076 } else {
1077 *last_len = 0;
1078 *skip = extent_map_end(em);
1079 *defrag_end = 0;
1082 free_extent_map(em);
1083 return ret;
1087 * it doesn't do much good to defrag one or two pages
1088 * at a time. This pulls in a nice chunk of pages
1089 * to COW and defrag.
1091 * It also makes sure the delalloc code has enough
1092 * dirty data to avoid making new small extents as part
1093 * of the defrag
1095 * It's a good idea to start RA on this range
1096 * before calling this.
1098 static int cluster_pages_for_defrag(struct inode *inode,
1099 struct page **pages,
1100 unsigned long start_index,
1101 unsigned long num_pages)
1103 unsigned long file_end;
1104 u64 isize = i_size_read(inode);
1105 u64 page_start;
1106 u64 page_end;
1107 u64 page_cnt;
1108 int ret;
1109 int i;
1110 int i_done;
1111 struct btrfs_ordered_extent *ordered;
1112 struct extent_state *cached_state = NULL;
1113 struct extent_io_tree *tree;
1114 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1116 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1117 if (!isize || start_index > file_end)
1118 return 0;
1120 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1122 ret = btrfs_delalloc_reserve_space(inode,
1123 page_cnt << PAGE_CACHE_SHIFT);
1124 if (ret)
1125 return ret;
1126 i_done = 0;
1127 tree = &BTRFS_I(inode)->io_tree;
1129 /* step one, lock all the pages */
1130 for (i = 0; i < page_cnt; i++) {
1131 struct page *page;
1132 again:
1133 page = find_or_create_page(inode->i_mapping,
1134 start_index + i, mask);
1135 if (!page)
1136 break;
1138 page_start = page_offset(page);
1139 page_end = page_start + PAGE_CACHE_SIZE - 1;
1140 while (1) {
1141 lock_extent_bits(tree, page_start, page_end,
1142 0, &cached_state);
1143 ordered = btrfs_lookup_ordered_extent(inode,
1144 page_start);
1145 unlock_extent_cached(tree, page_start, page_end,
1146 &cached_state, GFP_NOFS);
1147 if (!ordered)
1148 break;
1150 unlock_page(page);
1151 btrfs_start_ordered_extent(inode, ordered, 1);
1152 btrfs_put_ordered_extent(ordered);
1153 lock_page(page);
1155 * we unlocked the page above, so we need check if
1156 * it was released or not.
1158 if (page->mapping != inode->i_mapping) {
1159 unlock_page(page);
1160 page_cache_release(page);
1161 goto again;
1165 if (!PageUptodate(page)) {
1166 btrfs_readpage(NULL, page);
1167 lock_page(page);
1168 if (!PageUptodate(page)) {
1169 unlock_page(page);
1170 page_cache_release(page);
1171 ret = -EIO;
1172 break;
1176 if (page->mapping != inode->i_mapping) {
1177 unlock_page(page);
1178 page_cache_release(page);
1179 goto again;
1182 pages[i] = page;
1183 i_done++;
1185 if (!i_done || ret)
1186 goto out;
1188 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1189 goto out;
1192 * so now we have a nice long stream of locked
1193 * and up to date pages, lets wait on them
1195 for (i = 0; i < i_done; i++)
1196 wait_on_page_writeback(pages[i]);
1198 page_start = page_offset(pages[0]);
1199 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1201 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1202 page_start, page_end - 1, 0, &cached_state);
1203 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1204 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1205 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1206 &cached_state, GFP_NOFS);
1208 if (i_done != page_cnt) {
1209 spin_lock(&BTRFS_I(inode)->lock);
1210 BTRFS_I(inode)->outstanding_extents++;
1211 spin_unlock(&BTRFS_I(inode)->lock);
1212 btrfs_delalloc_release_space(inode,
1213 (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1217 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1218 &cached_state, GFP_NOFS);
1220 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1221 page_start, page_end - 1, &cached_state,
1222 GFP_NOFS);
1224 for (i = 0; i < i_done; i++) {
1225 clear_page_dirty_for_io(pages[i]);
1226 ClearPageChecked(pages[i]);
1227 set_page_extent_mapped(pages[i]);
1228 set_page_dirty(pages[i]);
1229 unlock_page(pages[i]);
1230 page_cache_release(pages[i]);
1232 return i_done;
1233 out:
1234 for (i = 0; i < i_done; i++) {
1235 unlock_page(pages[i]);
1236 page_cache_release(pages[i]);
1238 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1239 return ret;
1243 int btrfs_defrag_file(struct inode *inode, struct file *file,
1244 struct btrfs_ioctl_defrag_range_args *range,
1245 u64 newer_than, unsigned long max_to_defrag)
1247 struct btrfs_root *root = BTRFS_I(inode)->root;
1248 struct file_ra_state *ra = NULL;
1249 unsigned long last_index;
1250 u64 isize = i_size_read(inode);
1251 u64 last_len = 0;
1252 u64 skip = 0;
1253 u64 defrag_end = 0;
1254 u64 newer_off = range->start;
1255 unsigned long i;
1256 unsigned long ra_index = 0;
1257 int ret;
1258 int defrag_count = 0;
1259 int compress_type = BTRFS_COMPRESS_ZLIB;
1260 u32 extent_thresh = range->extent_thresh;
1261 unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1262 unsigned long cluster = max_cluster;
1263 u64 new_align = ~((u64)128 * 1024 - 1);
1264 struct page **pages = NULL;
1266 if (isize == 0)
1267 return 0;
1269 if (range->start >= isize)
1270 return -EINVAL;
1272 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1273 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1274 return -EINVAL;
1275 if (range->compress_type)
1276 compress_type = range->compress_type;
1279 if (extent_thresh == 0)
1280 extent_thresh = 256 * 1024;
1283 * if we were not given a file, allocate a readahead
1284 * context
1286 if (!file) {
1287 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1288 if (!ra)
1289 return -ENOMEM;
1290 file_ra_state_init(ra, inode->i_mapping);
1291 } else {
1292 ra = &file->f_ra;
1295 pages = kmalloc_array(max_cluster, sizeof(struct page *),
1296 GFP_NOFS);
1297 if (!pages) {
1298 ret = -ENOMEM;
1299 goto out_ra;
1302 /* find the last page to defrag */
1303 if (range->start + range->len > range->start) {
1304 last_index = min_t(u64, isize - 1,
1305 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1306 } else {
1307 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1310 if (newer_than) {
1311 ret = find_new_extents(root, inode, newer_than,
1312 &newer_off, 64 * 1024);
1313 if (!ret) {
1314 range->start = newer_off;
1316 * we always align our defrag to help keep
1317 * the extents in the file evenly spaced
1319 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1320 } else
1321 goto out_ra;
1322 } else {
1323 i = range->start >> PAGE_CACHE_SHIFT;
1325 if (!max_to_defrag)
1326 max_to_defrag = last_index - i + 1;
1329 * make writeback starts from i, so the defrag range can be
1330 * written sequentially.
1332 if (i < inode->i_mapping->writeback_index)
1333 inode->i_mapping->writeback_index = i;
1335 while (i <= last_index && defrag_count < max_to_defrag &&
1336 (i < DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE))) {
1338 * make sure we stop running if someone unmounts
1339 * the FS
1341 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1342 break;
1344 if (btrfs_defrag_cancelled(root->fs_info)) {
1345 printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n");
1346 ret = -EAGAIN;
1347 break;
1350 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1351 extent_thresh, &last_len, &skip,
1352 &defrag_end, range->flags &
1353 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1354 unsigned long next;
1356 * the should_defrag function tells us how much to skip
1357 * bump our counter by the suggested amount
1359 next = DIV_ROUND_UP(skip, PAGE_CACHE_SIZE);
1360 i = max(i + 1, next);
1361 continue;
1364 if (!newer_than) {
1365 cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1366 PAGE_CACHE_SHIFT) - i;
1367 cluster = min(cluster, max_cluster);
1368 } else {
1369 cluster = max_cluster;
1372 if (i + cluster > ra_index) {
1373 ra_index = max(i, ra_index);
1374 btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1375 cluster);
1376 ra_index += cluster;
1379 mutex_lock(&inode->i_mutex);
1380 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1381 BTRFS_I(inode)->force_compress = compress_type;
1382 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1383 if (ret < 0) {
1384 mutex_unlock(&inode->i_mutex);
1385 goto out_ra;
1388 defrag_count += ret;
1389 balance_dirty_pages_ratelimited(inode->i_mapping);
1390 mutex_unlock(&inode->i_mutex);
1392 if (newer_than) {
1393 if (newer_off == (u64)-1)
1394 break;
1396 if (ret > 0)
1397 i += ret;
1399 newer_off = max(newer_off + 1,
1400 (u64)i << PAGE_CACHE_SHIFT);
1402 ret = find_new_extents(root, inode,
1403 newer_than, &newer_off,
1404 64 * 1024);
1405 if (!ret) {
1406 range->start = newer_off;
1407 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1408 } else {
1409 break;
1411 } else {
1412 if (ret > 0) {
1413 i += ret;
1414 last_len += ret << PAGE_CACHE_SHIFT;
1415 } else {
1416 i++;
1417 last_len = 0;
1422 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1423 filemap_flush(inode->i_mapping);
1424 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1425 &BTRFS_I(inode)->runtime_flags))
1426 filemap_flush(inode->i_mapping);
1429 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1430 /* the filemap_flush will queue IO into the worker threads, but
1431 * we have to make sure the IO is actually started and that
1432 * ordered extents get created before we return
1434 atomic_inc(&root->fs_info->async_submit_draining);
1435 while (atomic_read(&root->fs_info->nr_async_submits) ||
1436 atomic_read(&root->fs_info->async_delalloc_pages)) {
1437 wait_event(root->fs_info->async_submit_wait,
1438 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1439 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1441 atomic_dec(&root->fs_info->async_submit_draining);
1444 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1445 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1448 ret = defrag_count;
1450 out_ra:
1451 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1452 mutex_lock(&inode->i_mutex);
1453 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1454 mutex_unlock(&inode->i_mutex);
1456 if (!file)
1457 kfree(ra);
1458 kfree(pages);
1459 return ret;
1462 static noinline int btrfs_ioctl_resize(struct file *file,
1463 void __user *arg)
1465 u64 new_size;
1466 u64 old_size;
1467 u64 devid = 1;
1468 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
1469 struct btrfs_ioctl_vol_args *vol_args;
1470 struct btrfs_trans_handle *trans;
1471 struct btrfs_device *device = NULL;
1472 char *sizestr;
1473 char *retptr;
1474 char *devstr = NULL;
1475 int ret = 0;
1476 int mod = 0;
1478 if (!capable(CAP_SYS_ADMIN))
1479 return -EPERM;
1481 ret = mnt_want_write_file(file);
1482 if (ret)
1483 return ret;
1485 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1486 1)) {
1487 mnt_drop_write_file(file);
1488 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1491 mutex_lock(&root->fs_info->volume_mutex);
1492 vol_args = memdup_user(arg, sizeof(*vol_args));
1493 if (IS_ERR(vol_args)) {
1494 ret = PTR_ERR(vol_args);
1495 goto out;
1498 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1500 sizestr = vol_args->name;
1501 devstr = strchr(sizestr, ':');
1502 if (devstr) {
1503 sizestr = devstr + 1;
1504 *devstr = '\0';
1505 devstr = vol_args->name;
1506 ret = kstrtoull(devstr, 10, &devid);
1507 if (ret)
1508 goto out_free;
1509 if (!devid) {
1510 ret = -EINVAL;
1511 goto out_free;
1513 btrfs_info(root->fs_info, "resizing devid %llu", devid);
1516 device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1517 if (!device) {
1518 btrfs_info(root->fs_info, "resizer unable to find device %llu",
1519 devid);
1520 ret = -ENODEV;
1521 goto out_free;
1524 if (!device->writeable) {
1525 btrfs_info(root->fs_info,
1526 "resizer unable to apply on readonly device %llu",
1527 devid);
1528 ret = -EPERM;
1529 goto out_free;
1532 if (!strcmp(sizestr, "max"))
1533 new_size = device->bdev->bd_inode->i_size;
1534 else {
1535 if (sizestr[0] == '-') {
1536 mod = -1;
1537 sizestr++;
1538 } else if (sizestr[0] == '+') {
1539 mod = 1;
1540 sizestr++;
1542 new_size = memparse(sizestr, &retptr);
1543 if (*retptr != '\0' || new_size == 0) {
1544 ret = -EINVAL;
1545 goto out_free;
1549 if (device->is_tgtdev_for_dev_replace) {
1550 ret = -EPERM;
1551 goto out_free;
1554 old_size = btrfs_device_get_total_bytes(device);
1556 if (mod < 0) {
1557 if (new_size > old_size) {
1558 ret = -EINVAL;
1559 goto out_free;
1561 new_size = old_size - new_size;
1562 } else if (mod > 0) {
1563 if (new_size > ULLONG_MAX - old_size) {
1564 ret = -ERANGE;
1565 goto out_free;
1567 new_size = old_size + new_size;
1570 if (new_size < 256 * 1024 * 1024) {
1571 ret = -EINVAL;
1572 goto out_free;
1574 if (new_size > device->bdev->bd_inode->i_size) {
1575 ret = -EFBIG;
1576 goto out_free;
1579 new_size = div_u64(new_size, root->sectorsize);
1580 new_size *= root->sectorsize;
1582 printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n",
1583 rcu_str_deref(device->name), new_size);
1585 if (new_size > old_size) {
1586 trans = btrfs_start_transaction(root, 0);
1587 if (IS_ERR(trans)) {
1588 ret = PTR_ERR(trans);
1589 goto out_free;
1591 ret = btrfs_grow_device(trans, device, new_size);
1592 btrfs_commit_transaction(trans, root);
1593 } else if (new_size < old_size) {
1594 ret = btrfs_shrink_device(device, new_size);
1595 } /* equal, nothing need to do */
1597 out_free:
1598 kfree(vol_args);
1599 out:
1600 mutex_unlock(&root->fs_info->volume_mutex);
1601 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1602 mnt_drop_write_file(file);
1603 return ret;
1606 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1607 char *name, unsigned long fd, int subvol,
1608 u64 *transid, bool readonly,
1609 struct btrfs_qgroup_inherit *inherit)
1611 int namelen;
1612 int ret = 0;
1614 ret = mnt_want_write_file(file);
1615 if (ret)
1616 goto out;
1618 namelen = strlen(name);
1619 if (strchr(name, '/')) {
1620 ret = -EINVAL;
1621 goto out_drop_write;
1624 if (name[0] == '.' &&
1625 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1626 ret = -EEXIST;
1627 goto out_drop_write;
1630 if (subvol) {
1631 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1632 NULL, transid, readonly, inherit);
1633 } else {
1634 struct fd src = fdget(fd);
1635 struct inode *src_inode;
1636 if (!src.file) {
1637 ret = -EINVAL;
1638 goto out_drop_write;
1641 src_inode = file_inode(src.file);
1642 if (src_inode->i_sb != file_inode(file)->i_sb) {
1643 btrfs_info(BTRFS_I(src_inode)->root->fs_info,
1644 "Snapshot src from another FS");
1645 ret = -EXDEV;
1646 } else if (!inode_owner_or_capable(src_inode)) {
1648 * Subvolume creation is not restricted, but snapshots
1649 * are limited to own subvolumes only
1651 ret = -EPERM;
1652 } else {
1653 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1654 BTRFS_I(src_inode)->root,
1655 transid, readonly, inherit);
1657 fdput(src);
1659 out_drop_write:
1660 mnt_drop_write_file(file);
1661 out:
1662 return ret;
1665 static noinline int btrfs_ioctl_snap_create(struct file *file,
1666 void __user *arg, int subvol)
1668 struct btrfs_ioctl_vol_args *vol_args;
1669 int ret;
1671 vol_args = memdup_user(arg, sizeof(*vol_args));
1672 if (IS_ERR(vol_args))
1673 return PTR_ERR(vol_args);
1674 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1676 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1677 vol_args->fd, subvol,
1678 NULL, false, NULL);
1680 kfree(vol_args);
1681 return ret;
1684 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1685 void __user *arg, int subvol)
1687 struct btrfs_ioctl_vol_args_v2 *vol_args;
1688 int ret;
1689 u64 transid = 0;
1690 u64 *ptr = NULL;
1691 bool readonly = false;
1692 struct btrfs_qgroup_inherit *inherit = NULL;
1694 vol_args = memdup_user(arg, sizeof(*vol_args));
1695 if (IS_ERR(vol_args))
1696 return PTR_ERR(vol_args);
1697 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1699 if (vol_args->flags &
1700 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1701 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1702 ret = -EOPNOTSUPP;
1703 goto free_args;
1706 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1707 ptr = &transid;
1708 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1709 readonly = true;
1710 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1711 if (vol_args->size > PAGE_CACHE_SIZE) {
1712 ret = -EINVAL;
1713 goto free_args;
1715 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1716 if (IS_ERR(inherit)) {
1717 ret = PTR_ERR(inherit);
1718 goto free_args;
1722 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1723 vol_args->fd, subvol, ptr,
1724 readonly, inherit);
1725 if (ret)
1726 goto free_inherit;
1728 if (ptr && copy_to_user(arg +
1729 offsetof(struct btrfs_ioctl_vol_args_v2,
1730 transid),
1731 ptr, sizeof(*ptr)))
1732 ret = -EFAULT;
1734 free_inherit:
1735 kfree(inherit);
1736 free_args:
1737 kfree(vol_args);
1738 return ret;
1741 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1742 void __user *arg)
1744 struct inode *inode = file_inode(file);
1745 struct btrfs_root *root = BTRFS_I(inode)->root;
1746 int ret = 0;
1747 u64 flags = 0;
1749 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1750 return -EINVAL;
1752 down_read(&root->fs_info->subvol_sem);
1753 if (btrfs_root_readonly(root))
1754 flags |= BTRFS_SUBVOL_RDONLY;
1755 up_read(&root->fs_info->subvol_sem);
1757 if (copy_to_user(arg, &flags, sizeof(flags)))
1758 ret = -EFAULT;
1760 return ret;
1763 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1764 void __user *arg)
1766 struct inode *inode = file_inode(file);
1767 struct btrfs_root *root = BTRFS_I(inode)->root;
1768 struct btrfs_trans_handle *trans;
1769 u64 root_flags;
1770 u64 flags;
1771 int ret = 0;
1773 if (!inode_owner_or_capable(inode))
1774 return -EPERM;
1776 ret = mnt_want_write_file(file);
1777 if (ret)
1778 goto out;
1780 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1781 ret = -EINVAL;
1782 goto out_drop_write;
1785 if (copy_from_user(&flags, arg, sizeof(flags))) {
1786 ret = -EFAULT;
1787 goto out_drop_write;
1790 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1791 ret = -EINVAL;
1792 goto out_drop_write;
1795 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1796 ret = -EOPNOTSUPP;
1797 goto out_drop_write;
1800 down_write(&root->fs_info->subvol_sem);
1802 /* nothing to do */
1803 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1804 goto out_drop_sem;
1806 root_flags = btrfs_root_flags(&root->root_item);
1807 if (flags & BTRFS_SUBVOL_RDONLY) {
1808 btrfs_set_root_flags(&root->root_item,
1809 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1810 } else {
1812 * Block RO -> RW transition if this subvolume is involved in
1813 * send
1815 spin_lock(&root->root_item_lock);
1816 if (root->send_in_progress == 0) {
1817 btrfs_set_root_flags(&root->root_item,
1818 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1819 spin_unlock(&root->root_item_lock);
1820 } else {
1821 spin_unlock(&root->root_item_lock);
1822 btrfs_warn(root->fs_info,
1823 "Attempt to set subvolume %llu read-write during send",
1824 root->root_key.objectid);
1825 ret = -EPERM;
1826 goto out_drop_sem;
1830 trans = btrfs_start_transaction(root, 1);
1831 if (IS_ERR(trans)) {
1832 ret = PTR_ERR(trans);
1833 goto out_reset;
1836 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1837 &root->root_key, &root->root_item);
1839 btrfs_commit_transaction(trans, root);
1840 out_reset:
1841 if (ret)
1842 btrfs_set_root_flags(&root->root_item, root_flags);
1843 out_drop_sem:
1844 up_write(&root->fs_info->subvol_sem);
1845 out_drop_write:
1846 mnt_drop_write_file(file);
1847 out:
1848 return ret;
1852 * helper to check if the subvolume references other subvolumes
1854 static noinline int may_destroy_subvol(struct btrfs_root *root)
1856 struct btrfs_path *path;
1857 struct btrfs_dir_item *di;
1858 struct btrfs_key key;
1859 u64 dir_id;
1860 int ret;
1862 path = btrfs_alloc_path();
1863 if (!path)
1864 return -ENOMEM;
1866 /* Make sure this root isn't set as the default subvol */
1867 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
1868 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
1869 dir_id, "default", 7, 0);
1870 if (di && !IS_ERR(di)) {
1871 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1872 if (key.objectid == root->root_key.objectid) {
1873 ret = -EPERM;
1874 btrfs_err(root->fs_info, "deleting default subvolume "
1875 "%llu is not allowed", key.objectid);
1876 goto out;
1878 btrfs_release_path(path);
1881 key.objectid = root->root_key.objectid;
1882 key.type = BTRFS_ROOT_REF_KEY;
1883 key.offset = (u64)-1;
1885 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1886 &key, path, 0, 0);
1887 if (ret < 0)
1888 goto out;
1889 BUG_ON(ret == 0);
1891 ret = 0;
1892 if (path->slots[0] > 0) {
1893 path->slots[0]--;
1894 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1895 if (key.objectid == root->root_key.objectid &&
1896 key.type == BTRFS_ROOT_REF_KEY)
1897 ret = -ENOTEMPTY;
1899 out:
1900 btrfs_free_path(path);
1901 return ret;
1904 static noinline int key_in_sk(struct btrfs_key *key,
1905 struct btrfs_ioctl_search_key *sk)
1907 struct btrfs_key test;
1908 int ret;
1910 test.objectid = sk->min_objectid;
1911 test.type = sk->min_type;
1912 test.offset = sk->min_offset;
1914 ret = btrfs_comp_cpu_keys(key, &test);
1915 if (ret < 0)
1916 return 0;
1918 test.objectid = sk->max_objectid;
1919 test.type = sk->max_type;
1920 test.offset = sk->max_offset;
1922 ret = btrfs_comp_cpu_keys(key, &test);
1923 if (ret > 0)
1924 return 0;
1925 return 1;
1928 static noinline int copy_to_sk(struct btrfs_root *root,
1929 struct btrfs_path *path,
1930 struct btrfs_key *key,
1931 struct btrfs_ioctl_search_key *sk,
1932 size_t *buf_size,
1933 char __user *ubuf,
1934 unsigned long *sk_offset,
1935 int *num_found)
1937 u64 found_transid;
1938 struct extent_buffer *leaf;
1939 struct btrfs_ioctl_search_header sh;
1940 struct btrfs_key test;
1941 unsigned long item_off;
1942 unsigned long item_len;
1943 int nritems;
1944 int i;
1945 int slot;
1946 int ret = 0;
1948 leaf = path->nodes[0];
1949 slot = path->slots[0];
1950 nritems = btrfs_header_nritems(leaf);
1952 if (btrfs_header_generation(leaf) > sk->max_transid) {
1953 i = nritems;
1954 goto advance_key;
1956 found_transid = btrfs_header_generation(leaf);
1958 for (i = slot; i < nritems; i++) {
1959 item_off = btrfs_item_ptr_offset(leaf, i);
1960 item_len = btrfs_item_size_nr(leaf, i);
1962 btrfs_item_key_to_cpu(leaf, key, i);
1963 if (!key_in_sk(key, sk))
1964 continue;
1966 if (sizeof(sh) + item_len > *buf_size) {
1967 if (*num_found) {
1968 ret = 1;
1969 goto out;
1973 * return one empty item back for v1, which does not
1974 * handle -EOVERFLOW
1977 *buf_size = sizeof(sh) + item_len;
1978 item_len = 0;
1979 ret = -EOVERFLOW;
1982 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
1983 ret = 1;
1984 goto out;
1987 sh.objectid = key->objectid;
1988 sh.offset = key->offset;
1989 sh.type = key->type;
1990 sh.len = item_len;
1991 sh.transid = found_transid;
1993 /* copy search result header */
1994 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
1995 ret = -EFAULT;
1996 goto out;
1999 *sk_offset += sizeof(sh);
2001 if (item_len) {
2002 char __user *up = ubuf + *sk_offset;
2003 /* copy the item */
2004 if (read_extent_buffer_to_user(leaf, up,
2005 item_off, item_len)) {
2006 ret = -EFAULT;
2007 goto out;
2010 *sk_offset += item_len;
2012 (*num_found)++;
2014 if (ret) /* -EOVERFLOW from above */
2015 goto out;
2017 if (*num_found >= sk->nr_items) {
2018 ret = 1;
2019 goto out;
2022 advance_key:
2023 ret = 0;
2024 test.objectid = sk->max_objectid;
2025 test.type = sk->max_type;
2026 test.offset = sk->max_offset;
2027 if (btrfs_comp_cpu_keys(key, &test) >= 0)
2028 ret = 1;
2029 else if (key->offset < (u64)-1)
2030 key->offset++;
2031 else if (key->type < (u8)-1) {
2032 key->offset = 0;
2033 key->type++;
2034 } else if (key->objectid < (u64)-1) {
2035 key->offset = 0;
2036 key->type = 0;
2037 key->objectid++;
2038 } else
2039 ret = 1;
2040 out:
2042 * 0: all items from this leaf copied, continue with next
2043 * 1: * more items can be copied, but unused buffer is too small
2044 * * all items were found
2045 * Either way, it will stops the loop which iterates to the next
2046 * leaf
2047 * -EOVERFLOW: item was to large for buffer
2048 * -EFAULT: could not copy extent buffer back to userspace
2050 return ret;
2053 static noinline int search_ioctl(struct inode *inode,
2054 struct btrfs_ioctl_search_key *sk,
2055 size_t *buf_size,
2056 char __user *ubuf)
2058 struct btrfs_root *root;
2059 struct btrfs_key key;
2060 struct btrfs_path *path;
2061 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
2062 int ret;
2063 int num_found = 0;
2064 unsigned long sk_offset = 0;
2066 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2067 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2068 return -EOVERFLOW;
2071 path = btrfs_alloc_path();
2072 if (!path)
2073 return -ENOMEM;
2075 if (sk->tree_id == 0) {
2076 /* search the root of the inode that was passed */
2077 root = BTRFS_I(inode)->root;
2078 } else {
2079 key.objectid = sk->tree_id;
2080 key.type = BTRFS_ROOT_ITEM_KEY;
2081 key.offset = (u64)-1;
2082 root = btrfs_read_fs_root_no_name(info, &key);
2083 if (IS_ERR(root)) {
2084 printk(KERN_ERR "BTRFS: could not find root %llu\n",
2085 sk->tree_id);
2086 btrfs_free_path(path);
2087 return -ENOENT;
2091 key.objectid = sk->min_objectid;
2092 key.type = sk->min_type;
2093 key.offset = sk->min_offset;
2095 while (1) {
2096 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2097 if (ret != 0) {
2098 if (ret > 0)
2099 ret = 0;
2100 goto err;
2102 ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf,
2103 &sk_offset, &num_found);
2104 btrfs_release_path(path);
2105 if (ret)
2106 break;
2109 if (ret > 0)
2110 ret = 0;
2111 err:
2112 sk->nr_items = num_found;
2113 btrfs_free_path(path);
2114 return ret;
2117 static noinline int btrfs_ioctl_tree_search(struct file *file,
2118 void __user *argp)
2120 struct btrfs_ioctl_search_args __user *uargs;
2121 struct btrfs_ioctl_search_key sk;
2122 struct inode *inode;
2123 int ret;
2124 size_t buf_size;
2126 if (!capable(CAP_SYS_ADMIN))
2127 return -EPERM;
2129 uargs = (struct btrfs_ioctl_search_args __user *)argp;
2131 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2132 return -EFAULT;
2134 buf_size = sizeof(uargs->buf);
2136 inode = file_inode(file);
2137 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2140 * In the origin implementation an overflow is handled by returning a
2141 * search header with a len of zero, so reset ret.
2143 if (ret == -EOVERFLOW)
2144 ret = 0;
2146 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2147 ret = -EFAULT;
2148 return ret;
2151 static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2152 void __user *argp)
2154 struct btrfs_ioctl_search_args_v2 __user *uarg;
2155 struct btrfs_ioctl_search_args_v2 args;
2156 struct inode *inode;
2157 int ret;
2158 size_t buf_size;
2159 const size_t buf_limit = 16 * 1024 * 1024;
2161 if (!capable(CAP_SYS_ADMIN))
2162 return -EPERM;
2164 /* copy search header and buffer size */
2165 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2166 if (copy_from_user(&args, uarg, sizeof(args)))
2167 return -EFAULT;
2169 buf_size = args.buf_size;
2171 if (buf_size < sizeof(struct btrfs_ioctl_search_header))
2172 return -EOVERFLOW;
2174 /* limit result size to 16MB */
2175 if (buf_size > buf_limit)
2176 buf_size = buf_limit;
2178 inode = file_inode(file);
2179 ret = search_ioctl(inode, &args.key, &buf_size,
2180 (char *)(&uarg->buf[0]));
2181 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2182 ret = -EFAULT;
2183 else if (ret == -EOVERFLOW &&
2184 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2185 ret = -EFAULT;
2187 return ret;
2191 * Search INODE_REFs to identify path name of 'dirid' directory
2192 * in a 'tree_id' tree. and sets path name to 'name'.
2194 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2195 u64 tree_id, u64 dirid, char *name)
2197 struct btrfs_root *root;
2198 struct btrfs_key key;
2199 char *ptr;
2200 int ret = -1;
2201 int slot;
2202 int len;
2203 int total_len = 0;
2204 struct btrfs_inode_ref *iref;
2205 struct extent_buffer *l;
2206 struct btrfs_path *path;
2208 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2209 name[0]='\0';
2210 return 0;
2213 path = btrfs_alloc_path();
2214 if (!path)
2215 return -ENOMEM;
2217 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2219 key.objectid = tree_id;
2220 key.type = BTRFS_ROOT_ITEM_KEY;
2221 key.offset = (u64)-1;
2222 root = btrfs_read_fs_root_no_name(info, &key);
2223 if (IS_ERR(root)) {
2224 printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id);
2225 ret = -ENOENT;
2226 goto out;
2229 key.objectid = dirid;
2230 key.type = BTRFS_INODE_REF_KEY;
2231 key.offset = (u64)-1;
2233 while (1) {
2234 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2235 if (ret < 0)
2236 goto out;
2237 else if (ret > 0) {
2238 ret = btrfs_previous_item(root, path, dirid,
2239 BTRFS_INODE_REF_KEY);
2240 if (ret < 0)
2241 goto out;
2242 else if (ret > 0) {
2243 ret = -ENOENT;
2244 goto out;
2248 l = path->nodes[0];
2249 slot = path->slots[0];
2250 btrfs_item_key_to_cpu(l, &key, slot);
2252 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2253 len = btrfs_inode_ref_name_len(l, iref);
2254 ptr -= len + 1;
2255 total_len += len + 1;
2256 if (ptr < name) {
2257 ret = -ENAMETOOLONG;
2258 goto out;
2261 *(ptr + len) = '/';
2262 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2264 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2265 break;
2267 btrfs_release_path(path);
2268 key.objectid = key.offset;
2269 key.offset = (u64)-1;
2270 dirid = key.objectid;
2272 memmove(name, ptr, total_len);
2273 name[total_len] = '\0';
2274 ret = 0;
2275 out:
2276 btrfs_free_path(path);
2277 return ret;
2280 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2281 void __user *argp)
2283 struct btrfs_ioctl_ino_lookup_args *args;
2284 struct inode *inode;
2285 int ret = 0;
2287 args = memdup_user(argp, sizeof(*args));
2288 if (IS_ERR(args))
2289 return PTR_ERR(args);
2291 inode = file_inode(file);
2294 * Unprivileged query to obtain the containing subvolume root id. The
2295 * path is reset so it's consistent with btrfs_search_path_in_tree.
2297 if (args->treeid == 0)
2298 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2300 if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2301 args->name[0] = 0;
2302 goto out;
2305 if (!capable(CAP_SYS_ADMIN)) {
2306 ret = -EPERM;
2307 goto out;
2310 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2311 args->treeid, args->objectid,
2312 args->name);
2314 out:
2315 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2316 ret = -EFAULT;
2318 kfree(args);
2319 return ret;
2322 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2323 void __user *arg)
2325 struct dentry *parent = file->f_path.dentry;
2326 struct dentry *dentry;
2327 struct inode *dir = d_inode(parent);
2328 struct inode *inode;
2329 struct btrfs_root *root = BTRFS_I(dir)->root;
2330 struct btrfs_root *dest = NULL;
2331 struct btrfs_ioctl_vol_args *vol_args;
2332 struct btrfs_trans_handle *trans;
2333 struct btrfs_block_rsv block_rsv;
2334 u64 root_flags;
2335 u64 qgroup_reserved;
2336 int namelen;
2337 int ret;
2338 int err = 0;
2340 vol_args = memdup_user(arg, sizeof(*vol_args));
2341 if (IS_ERR(vol_args))
2342 return PTR_ERR(vol_args);
2344 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2345 namelen = strlen(vol_args->name);
2346 if (strchr(vol_args->name, '/') ||
2347 strncmp(vol_args->name, "..", namelen) == 0) {
2348 err = -EINVAL;
2349 goto out;
2352 err = mnt_want_write_file(file);
2353 if (err)
2354 goto out;
2357 err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
2358 if (err == -EINTR)
2359 goto out_drop_write;
2360 dentry = lookup_one_len(vol_args->name, parent, namelen);
2361 if (IS_ERR(dentry)) {
2362 err = PTR_ERR(dentry);
2363 goto out_unlock_dir;
2366 if (d_really_is_negative(dentry)) {
2367 err = -ENOENT;
2368 goto out_dput;
2371 inode = d_inode(dentry);
2372 dest = BTRFS_I(inode)->root;
2373 if (!capable(CAP_SYS_ADMIN)) {
2375 * Regular user. Only allow this with a special mount
2376 * option, when the user has write+exec access to the
2377 * subvol root, and when rmdir(2) would have been
2378 * allowed.
2380 * Note that this is _not_ check that the subvol is
2381 * empty or doesn't contain data that we wouldn't
2382 * otherwise be able to delete.
2384 * Users who want to delete empty subvols should try
2385 * rmdir(2).
2387 err = -EPERM;
2388 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2389 goto out_dput;
2392 * Do not allow deletion if the parent dir is the same
2393 * as the dir to be deleted. That means the ioctl
2394 * must be called on the dentry referencing the root
2395 * of the subvol, not a random directory contained
2396 * within it.
2398 err = -EINVAL;
2399 if (root == dest)
2400 goto out_dput;
2402 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2403 if (err)
2404 goto out_dput;
2407 /* check if subvolume may be deleted by a user */
2408 err = btrfs_may_delete(dir, dentry, 1);
2409 if (err)
2410 goto out_dput;
2412 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2413 err = -EINVAL;
2414 goto out_dput;
2417 mutex_lock(&inode->i_mutex);
2420 * Don't allow to delete a subvolume with send in progress. This is
2421 * inside the i_mutex so the error handling that has to drop the bit
2422 * again is not run concurrently.
2424 spin_lock(&dest->root_item_lock);
2425 root_flags = btrfs_root_flags(&dest->root_item);
2426 if (dest->send_in_progress == 0) {
2427 btrfs_set_root_flags(&dest->root_item,
2428 root_flags | BTRFS_ROOT_SUBVOL_DEAD);
2429 spin_unlock(&dest->root_item_lock);
2430 } else {
2431 spin_unlock(&dest->root_item_lock);
2432 btrfs_warn(root->fs_info,
2433 "Attempt to delete subvolume %llu during send",
2434 dest->root_key.objectid);
2435 err = -EPERM;
2436 goto out_unlock_inode;
2439 down_write(&root->fs_info->subvol_sem);
2441 err = may_destroy_subvol(dest);
2442 if (err)
2443 goto out_up_write;
2445 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2447 * One for dir inode, two for dir entries, two for root
2448 * ref/backref.
2450 err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2451 5, &qgroup_reserved, true);
2452 if (err)
2453 goto out_up_write;
2455 trans = btrfs_start_transaction(root, 0);
2456 if (IS_ERR(trans)) {
2457 err = PTR_ERR(trans);
2458 goto out_release;
2460 trans->block_rsv = &block_rsv;
2461 trans->bytes_reserved = block_rsv.size;
2463 ret = btrfs_unlink_subvol(trans, root, dir,
2464 dest->root_key.objectid,
2465 dentry->d_name.name,
2466 dentry->d_name.len);
2467 if (ret) {
2468 err = ret;
2469 btrfs_abort_transaction(trans, root, ret);
2470 goto out_end_trans;
2473 btrfs_record_root_in_trans(trans, dest);
2475 memset(&dest->root_item.drop_progress, 0,
2476 sizeof(dest->root_item.drop_progress));
2477 dest->root_item.drop_level = 0;
2478 btrfs_set_root_refs(&dest->root_item, 0);
2480 if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
2481 ret = btrfs_insert_orphan_item(trans,
2482 root->fs_info->tree_root,
2483 dest->root_key.objectid);
2484 if (ret) {
2485 btrfs_abort_transaction(trans, root, ret);
2486 err = ret;
2487 goto out_end_trans;
2491 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2492 dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
2493 dest->root_key.objectid);
2494 if (ret && ret != -ENOENT) {
2495 btrfs_abort_transaction(trans, root, ret);
2496 err = ret;
2497 goto out_end_trans;
2499 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
2500 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2501 dest->root_item.received_uuid,
2502 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
2503 dest->root_key.objectid);
2504 if (ret && ret != -ENOENT) {
2505 btrfs_abort_transaction(trans, root, ret);
2506 err = ret;
2507 goto out_end_trans;
2511 out_end_trans:
2512 trans->block_rsv = NULL;
2513 trans->bytes_reserved = 0;
2514 ret = btrfs_end_transaction(trans, root);
2515 if (ret && !err)
2516 err = ret;
2517 inode->i_flags |= S_DEAD;
2518 out_release:
2519 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2520 out_up_write:
2521 up_write(&root->fs_info->subvol_sem);
2522 if (err) {
2523 spin_lock(&dest->root_item_lock);
2524 root_flags = btrfs_root_flags(&dest->root_item);
2525 btrfs_set_root_flags(&dest->root_item,
2526 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
2527 spin_unlock(&dest->root_item_lock);
2529 out_unlock_inode:
2530 mutex_unlock(&inode->i_mutex);
2531 if (!err) {
2532 d_invalidate(dentry);
2533 btrfs_invalidate_inodes(dest);
2534 d_delete(dentry);
2535 ASSERT(dest->send_in_progress == 0);
2537 /* the last ref */
2538 if (dest->ino_cache_inode) {
2539 iput(dest->ino_cache_inode);
2540 dest->ino_cache_inode = NULL;
2543 out_dput:
2544 dput(dentry);
2545 out_unlock_dir:
2546 mutex_unlock(&dir->i_mutex);
2547 out_drop_write:
2548 mnt_drop_write_file(file);
2549 out:
2550 kfree(vol_args);
2551 return err;
2554 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2556 struct inode *inode = file_inode(file);
2557 struct btrfs_root *root = BTRFS_I(inode)->root;
2558 struct btrfs_ioctl_defrag_range_args *range;
2559 int ret;
2561 ret = mnt_want_write_file(file);
2562 if (ret)
2563 return ret;
2565 if (btrfs_root_readonly(root)) {
2566 ret = -EROFS;
2567 goto out;
2570 switch (inode->i_mode & S_IFMT) {
2571 case S_IFDIR:
2572 if (!capable(CAP_SYS_ADMIN)) {
2573 ret = -EPERM;
2574 goto out;
2576 ret = btrfs_defrag_root(root);
2577 if (ret)
2578 goto out;
2579 ret = btrfs_defrag_root(root->fs_info->extent_root);
2580 break;
2581 case S_IFREG:
2582 if (!(file->f_mode & FMODE_WRITE)) {
2583 ret = -EINVAL;
2584 goto out;
2587 range = kzalloc(sizeof(*range), GFP_KERNEL);
2588 if (!range) {
2589 ret = -ENOMEM;
2590 goto out;
2593 if (argp) {
2594 if (copy_from_user(range, argp,
2595 sizeof(*range))) {
2596 ret = -EFAULT;
2597 kfree(range);
2598 goto out;
2600 /* compression requires us to start the IO */
2601 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2602 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2603 range->extent_thresh = (u32)-1;
2605 } else {
2606 /* the rest are all set to zero by kzalloc */
2607 range->len = (u64)-1;
2609 ret = btrfs_defrag_file(file_inode(file), file,
2610 range, 0, 0);
2611 if (ret > 0)
2612 ret = 0;
2613 kfree(range);
2614 break;
2615 default:
2616 ret = -EINVAL;
2618 out:
2619 mnt_drop_write_file(file);
2620 return ret;
2623 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2625 struct btrfs_ioctl_vol_args *vol_args;
2626 int ret;
2628 if (!capable(CAP_SYS_ADMIN))
2629 return -EPERM;
2631 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2632 1)) {
2633 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2636 mutex_lock(&root->fs_info->volume_mutex);
2637 vol_args = memdup_user(arg, sizeof(*vol_args));
2638 if (IS_ERR(vol_args)) {
2639 ret = PTR_ERR(vol_args);
2640 goto out;
2643 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2644 ret = btrfs_init_new_device(root, vol_args->name);
2646 if (!ret)
2647 btrfs_info(root->fs_info, "disk added %s",vol_args->name);
2649 kfree(vol_args);
2650 out:
2651 mutex_unlock(&root->fs_info->volume_mutex);
2652 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2653 return ret;
2656 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2658 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
2659 struct btrfs_ioctl_vol_args *vol_args;
2660 int ret;
2662 if (!capable(CAP_SYS_ADMIN))
2663 return -EPERM;
2665 ret = mnt_want_write_file(file);
2666 if (ret)
2667 return ret;
2669 vol_args = memdup_user(arg, sizeof(*vol_args));
2670 if (IS_ERR(vol_args)) {
2671 ret = PTR_ERR(vol_args);
2672 goto err_drop;
2675 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2677 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2678 1)) {
2679 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2680 goto out;
2683 mutex_lock(&root->fs_info->volume_mutex);
2684 ret = btrfs_rm_device(root, vol_args->name);
2685 mutex_unlock(&root->fs_info->volume_mutex);
2686 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2688 if (!ret)
2689 btrfs_info(root->fs_info, "disk deleted %s",vol_args->name);
2691 out:
2692 kfree(vol_args);
2693 err_drop:
2694 mnt_drop_write_file(file);
2695 return ret;
2698 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2700 struct btrfs_ioctl_fs_info_args *fi_args;
2701 struct btrfs_device *device;
2702 struct btrfs_device *next;
2703 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2704 int ret = 0;
2706 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2707 if (!fi_args)
2708 return -ENOMEM;
2710 mutex_lock(&fs_devices->device_list_mutex);
2711 fi_args->num_devices = fs_devices->num_devices;
2712 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2714 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2715 if (device->devid > fi_args->max_id)
2716 fi_args->max_id = device->devid;
2718 mutex_unlock(&fs_devices->device_list_mutex);
2720 fi_args->nodesize = root->fs_info->super_copy->nodesize;
2721 fi_args->sectorsize = root->fs_info->super_copy->sectorsize;
2722 fi_args->clone_alignment = root->fs_info->super_copy->sectorsize;
2724 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2725 ret = -EFAULT;
2727 kfree(fi_args);
2728 return ret;
2731 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2733 struct btrfs_ioctl_dev_info_args *di_args;
2734 struct btrfs_device *dev;
2735 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2736 int ret = 0;
2737 char *s_uuid = NULL;
2739 di_args = memdup_user(arg, sizeof(*di_args));
2740 if (IS_ERR(di_args))
2741 return PTR_ERR(di_args);
2743 if (!btrfs_is_empty_uuid(di_args->uuid))
2744 s_uuid = di_args->uuid;
2746 mutex_lock(&fs_devices->device_list_mutex);
2747 dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2749 if (!dev) {
2750 ret = -ENODEV;
2751 goto out;
2754 di_args->devid = dev->devid;
2755 di_args->bytes_used = btrfs_device_get_bytes_used(dev);
2756 di_args->total_bytes = btrfs_device_get_total_bytes(dev);
2757 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2758 if (dev->name) {
2759 struct rcu_string *name;
2761 rcu_read_lock();
2762 name = rcu_dereference(dev->name);
2763 strncpy(di_args->path, name->str, sizeof(di_args->path));
2764 rcu_read_unlock();
2765 di_args->path[sizeof(di_args->path) - 1] = 0;
2766 } else {
2767 di_args->path[0] = '\0';
2770 out:
2771 mutex_unlock(&fs_devices->device_list_mutex);
2772 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2773 ret = -EFAULT;
2775 kfree(di_args);
2776 return ret;
2779 static struct page *extent_same_get_page(struct inode *inode, pgoff_t index)
2781 struct page *page;
2782 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
2784 page = grab_cache_page(inode->i_mapping, index);
2785 if (!page)
2786 return NULL;
2788 if (!PageUptodate(page)) {
2789 if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
2791 return NULL;
2792 lock_page(page);
2793 if (!PageUptodate(page)) {
2794 unlock_page(page);
2795 page_cache_release(page);
2796 return NULL;
2799 unlock_page(page);
2801 return page;
2804 static int gather_extent_pages(struct inode *inode, struct page **pages,
2805 int num_pages, u64 off)
2807 int i;
2808 pgoff_t index = off >> PAGE_CACHE_SHIFT;
2810 for (i = 0; i < num_pages; i++) {
2811 pages[i] = extent_same_get_page(inode, index + i);
2812 if (!pages[i])
2813 return -ENOMEM;
2815 return 0;
2818 static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
2820 /* do any pending delalloc/csum calc on src, one way or
2821 another, and lock file content */
2822 while (1) {
2823 struct btrfs_ordered_extent *ordered;
2824 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2825 ordered = btrfs_lookup_first_ordered_extent(inode,
2826 off + len - 1);
2827 if ((!ordered ||
2828 ordered->file_offset + ordered->len <= off ||
2829 ordered->file_offset >= off + len) &&
2830 !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2831 off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
2832 if (ordered)
2833 btrfs_put_ordered_extent(ordered);
2834 break;
2836 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2837 if (ordered)
2838 btrfs_put_ordered_extent(ordered);
2839 btrfs_wait_ordered_range(inode, off, len);
2843 static void btrfs_double_inode_unlock(struct inode *inode1, struct inode *inode2)
2845 mutex_unlock(&inode1->i_mutex);
2846 mutex_unlock(&inode2->i_mutex);
2849 static void btrfs_double_inode_lock(struct inode *inode1, struct inode *inode2)
2851 if (inode1 < inode2)
2852 swap(inode1, inode2);
2854 mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
2855 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
2858 static void btrfs_double_extent_unlock(struct inode *inode1, u64 loff1,
2859 struct inode *inode2, u64 loff2, u64 len)
2861 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
2862 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
2865 static void btrfs_double_extent_lock(struct inode *inode1, u64 loff1,
2866 struct inode *inode2, u64 loff2, u64 len)
2868 if (inode1 < inode2) {
2869 swap(inode1, inode2);
2870 swap(loff1, loff2);
2872 lock_extent_range(inode1, loff1, len);
2873 lock_extent_range(inode2, loff2, len);
2876 struct cmp_pages {
2877 int num_pages;
2878 struct page **src_pages;
2879 struct page **dst_pages;
2882 static void btrfs_cmp_data_free(struct cmp_pages *cmp)
2884 int i;
2885 struct page *pg;
2887 for (i = 0; i < cmp->num_pages; i++) {
2888 pg = cmp->src_pages[i];
2889 if (pg)
2890 page_cache_release(pg);
2891 pg = cmp->dst_pages[i];
2892 if (pg)
2893 page_cache_release(pg);
2895 kfree(cmp->src_pages);
2896 kfree(cmp->dst_pages);
2899 static int btrfs_cmp_data_prepare(struct inode *src, u64 loff,
2900 struct inode *dst, u64 dst_loff,
2901 u64 len, struct cmp_pages *cmp)
2903 int ret;
2904 int num_pages = PAGE_CACHE_ALIGN(len) >> PAGE_CACHE_SHIFT;
2905 struct page **src_pgarr, **dst_pgarr;
2908 * We must gather up all the pages before we initiate our
2909 * extent locking. We use an array for the page pointers. Size
2910 * of the array is bounded by len, which is in turn bounded by
2911 * BTRFS_MAX_DEDUPE_LEN.
2913 src_pgarr = kzalloc(num_pages * sizeof(struct page *), GFP_NOFS);
2914 dst_pgarr = kzalloc(num_pages * sizeof(struct page *), GFP_NOFS);
2915 if (!src_pgarr || !dst_pgarr) {
2916 kfree(src_pgarr);
2917 kfree(dst_pgarr);
2918 return -ENOMEM;
2920 cmp->num_pages = num_pages;
2921 cmp->src_pages = src_pgarr;
2922 cmp->dst_pages = dst_pgarr;
2924 ret = gather_extent_pages(src, cmp->src_pages, cmp->num_pages, loff);
2925 if (ret)
2926 goto out;
2928 ret = gather_extent_pages(dst, cmp->dst_pages, cmp->num_pages, dst_loff);
2930 out:
2931 if (ret)
2932 btrfs_cmp_data_free(cmp);
2933 return 0;
2936 static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
2937 u64 dst_loff, u64 len, struct cmp_pages *cmp)
2939 int ret = 0;
2940 int i;
2941 struct page *src_page, *dst_page;
2942 unsigned int cmp_len = PAGE_CACHE_SIZE;
2943 void *addr, *dst_addr;
2945 i = 0;
2946 while (len) {
2947 if (len < PAGE_CACHE_SIZE)
2948 cmp_len = len;
2950 BUG_ON(i >= cmp->num_pages);
2952 src_page = cmp->src_pages[i];
2953 dst_page = cmp->dst_pages[i];
2955 addr = kmap_atomic(src_page);
2956 dst_addr = kmap_atomic(dst_page);
2958 flush_dcache_page(src_page);
2959 flush_dcache_page(dst_page);
2961 if (memcmp(addr, dst_addr, cmp_len))
2962 ret = BTRFS_SAME_DATA_DIFFERS;
2964 kunmap_atomic(addr);
2965 kunmap_atomic(dst_addr);
2967 if (ret)
2968 break;
2970 len -= cmp_len;
2971 i++;
2974 return ret;
2977 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 *plen,
2978 u64 olen)
2980 u64 len = *plen;
2981 u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
2983 if (off + olen > inode->i_size || off + olen < off)
2984 return -EINVAL;
2986 /* if we extend to eof, continue to block boundary */
2987 if (off + len == inode->i_size)
2988 *plen = len = ALIGN(inode->i_size, bs) - off;
2990 /* Check that we are block aligned - btrfs_clone() requires this */
2991 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
2992 return -EINVAL;
2994 return 0;
2997 static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
2998 struct inode *dst, u64 dst_loff)
3000 int ret;
3001 u64 len = olen;
3002 struct cmp_pages cmp;
3003 int same_inode = 0;
3004 u64 same_lock_start = 0;
3005 u64 same_lock_len = 0;
3007 if (src == dst)
3008 same_inode = 1;
3010 if (len == 0)
3011 return 0;
3013 if (same_inode) {
3014 mutex_lock(&src->i_mutex);
3016 ret = extent_same_check_offsets(src, loff, &len, olen);
3017 if (ret)
3018 goto out_unlock;
3021 * Single inode case wants the same checks, except we
3022 * don't want our length pushed out past i_size as
3023 * comparing that data range makes no sense.
3025 * extent_same_check_offsets() will do this for an
3026 * unaligned length at i_size, so catch it here and
3027 * reject the request.
3029 * This effectively means we require aligned extents
3030 * for the single-inode case, whereas the other cases
3031 * allow an unaligned length so long as it ends at
3032 * i_size.
3034 if (len != olen) {
3035 ret = -EINVAL;
3036 goto out_unlock;
3039 /* Check for overlapping ranges */
3040 if (dst_loff + len > loff && dst_loff < loff + len) {
3041 ret = -EINVAL;
3042 goto out_unlock;
3045 same_lock_start = min_t(u64, loff, dst_loff);
3046 same_lock_len = max_t(u64, loff, dst_loff) + len - same_lock_start;
3047 } else {
3048 btrfs_double_inode_lock(src, dst);
3050 ret = extent_same_check_offsets(src, loff, &len, olen);
3051 if (ret)
3052 goto out_unlock;
3054 ret = extent_same_check_offsets(dst, dst_loff, &len, olen);
3055 if (ret)
3056 goto out_unlock;
3059 /* don't make the dst file partly checksummed */
3060 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3061 (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
3062 ret = -EINVAL;
3063 goto out_unlock;
3066 ret = btrfs_cmp_data_prepare(src, loff, dst, dst_loff, olen, &cmp);
3067 if (ret)
3068 goto out_unlock;
3070 if (same_inode)
3071 lock_extent_range(src, same_lock_start, same_lock_len);
3072 else
3073 btrfs_double_extent_lock(src, loff, dst, dst_loff, len);
3075 /* pass original length for comparison so we stay within i_size */
3076 ret = btrfs_cmp_data(src, loff, dst, dst_loff, olen, &cmp);
3077 if (ret == 0)
3078 ret = btrfs_clone(src, dst, loff, olen, len, dst_loff, 1);
3080 if (same_inode)
3081 unlock_extent(&BTRFS_I(src)->io_tree, same_lock_start,
3082 same_lock_start + same_lock_len - 1);
3083 else
3084 btrfs_double_extent_unlock(src, loff, dst, dst_loff, len);
3086 btrfs_cmp_data_free(&cmp);
3087 out_unlock:
3088 if (same_inode)
3089 mutex_unlock(&src->i_mutex);
3090 else
3091 btrfs_double_inode_unlock(src, dst);
3093 return ret;
3096 #define BTRFS_MAX_DEDUPE_LEN (16 * 1024 * 1024)
3098 static long btrfs_ioctl_file_extent_same(struct file *file,
3099 struct btrfs_ioctl_same_args __user *argp)
3101 struct btrfs_ioctl_same_args *same = NULL;
3102 struct btrfs_ioctl_same_extent_info *info;
3103 struct inode *src = file_inode(file);
3104 u64 off;
3105 u64 len;
3106 int i;
3107 int ret;
3108 unsigned long size;
3109 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
3110 bool is_admin = capable(CAP_SYS_ADMIN);
3111 u16 count;
3113 if (!(file->f_mode & FMODE_READ))
3114 return -EINVAL;
3116 ret = mnt_want_write_file(file);
3117 if (ret)
3118 return ret;
3120 if (get_user(count, &argp->dest_count)) {
3121 ret = -EFAULT;
3122 goto out;
3125 size = offsetof(struct btrfs_ioctl_same_args __user, info[count]);
3127 same = memdup_user(argp, size);
3129 if (IS_ERR(same)) {
3130 ret = PTR_ERR(same);
3131 same = NULL;
3132 goto out;
3135 off = same->logical_offset;
3136 len = same->length;
3139 * Limit the total length we will dedupe for each operation.
3140 * This is intended to bound the total time spent in this
3141 * ioctl to something sane.
3143 if (len > BTRFS_MAX_DEDUPE_LEN)
3144 len = BTRFS_MAX_DEDUPE_LEN;
3146 if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
3148 * Btrfs does not support blocksize < page_size. As a
3149 * result, btrfs_cmp_data() won't correctly handle
3150 * this situation without an update.
3152 ret = -EINVAL;
3153 goto out;
3156 ret = -EISDIR;
3157 if (S_ISDIR(src->i_mode))
3158 goto out;
3160 ret = -EACCES;
3161 if (!S_ISREG(src->i_mode))
3162 goto out;
3164 /* pre-format output fields to sane values */
3165 for (i = 0; i < count; i++) {
3166 same->info[i].bytes_deduped = 0ULL;
3167 same->info[i].status = 0;
3170 for (i = 0, info = same->info; i < count; i++, info++) {
3171 struct inode *dst;
3172 struct fd dst_file = fdget(info->fd);
3173 if (!dst_file.file) {
3174 info->status = -EBADF;
3175 continue;
3177 dst = file_inode(dst_file.file);
3179 if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) {
3180 info->status = -EINVAL;
3181 } else if (file->f_path.mnt != dst_file.file->f_path.mnt) {
3182 info->status = -EXDEV;
3183 } else if (S_ISDIR(dst->i_mode)) {
3184 info->status = -EISDIR;
3185 } else if (!S_ISREG(dst->i_mode)) {
3186 info->status = -EACCES;
3187 } else {
3188 info->status = btrfs_extent_same(src, off, len, dst,
3189 info->logical_offset);
3190 if (info->status == 0)
3191 info->bytes_deduped += len;
3193 fdput(dst_file);
3196 ret = copy_to_user(argp, same, size);
3197 if (ret)
3198 ret = -EFAULT;
3200 out:
3201 mnt_drop_write_file(file);
3202 kfree(same);
3203 return ret;
3206 /* Helper to check and see if this root currently has a ref on the given disk
3207 * bytenr. If it does then we need to update the quota for this root. This
3208 * doesn't do anything if quotas aren't enabled.
3210 static int check_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3211 u64 disko)
3213 struct seq_list tree_mod_seq_elem = SEQ_LIST_INIT(tree_mod_seq_elem);
3214 struct ulist *roots;
3215 struct ulist_iterator uiter;
3216 struct ulist_node *root_node = NULL;
3217 int ret;
3219 if (!root->fs_info->quota_enabled)
3220 return 1;
3222 btrfs_get_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3223 ret = btrfs_find_all_roots(trans, root->fs_info, disko,
3224 tree_mod_seq_elem.seq, &roots);
3225 if (ret < 0)
3226 goto out;
3227 ret = 0;
3228 ULIST_ITER_INIT(&uiter);
3229 while ((root_node = ulist_next(roots, &uiter))) {
3230 if (root_node->val == root->objectid) {
3231 ret = 1;
3232 break;
3235 ulist_free(roots);
3236 out:
3237 btrfs_put_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3238 return ret;
3241 static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3242 struct inode *inode,
3243 u64 endoff,
3244 const u64 destoff,
3245 const u64 olen,
3246 int no_time_update)
3248 struct btrfs_root *root = BTRFS_I(inode)->root;
3249 int ret;
3251 inode_inc_iversion(inode);
3252 if (!no_time_update)
3253 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3255 * We round up to the block size at eof when determining which
3256 * extents to clone above, but shouldn't round up the file size.
3258 if (endoff > destoff + olen)
3259 endoff = destoff + olen;
3260 if (endoff > inode->i_size)
3261 btrfs_i_size_write(inode, endoff);
3263 ret = btrfs_update_inode(trans, root, inode);
3264 if (ret) {
3265 btrfs_abort_transaction(trans, root, ret);
3266 btrfs_end_transaction(trans, root);
3267 goto out;
3269 ret = btrfs_end_transaction(trans, root);
3270 out:
3271 return ret;
3274 static void clone_update_extent_map(struct inode *inode,
3275 const struct btrfs_trans_handle *trans,
3276 const struct btrfs_path *path,
3277 const u64 hole_offset,
3278 const u64 hole_len)
3280 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
3281 struct extent_map *em;
3282 int ret;
3284 em = alloc_extent_map();
3285 if (!em) {
3286 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3287 &BTRFS_I(inode)->runtime_flags);
3288 return;
3291 if (path) {
3292 struct btrfs_file_extent_item *fi;
3294 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
3295 struct btrfs_file_extent_item);
3296 btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
3297 em->generation = -1;
3298 if (btrfs_file_extent_type(path->nodes[0], fi) ==
3299 BTRFS_FILE_EXTENT_INLINE)
3300 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3301 &BTRFS_I(inode)->runtime_flags);
3302 } else {
3303 em->start = hole_offset;
3304 em->len = hole_len;
3305 em->ram_bytes = em->len;
3306 em->orig_start = hole_offset;
3307 em->block_start = EXTENT_MAP_HOLE;
3308 em->block_len = 0;
3309 em->orig_block_len = 0;
3310 em->compress_type = BTRFS_COMPRESS_NONE;
3311 em->generation = trans->transid;
3314 while (1) {
3315 write_lock(&em_tree->lock);
3316 ret = add_extent_mapping(em_tree, em, 1);
3317 write_unlock(&em_tree->lock);
3318 if (ret != -EEXIST) {
3319 free_extent_map(em);
3320 break;
3322 btrfs_drop_extent_cache(inode, em->start,
3323 em->start + em->len - 1, 0);
3326 if (ret)
3327 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3328 &BTRFS_I(inode)->runtime_flags);
3332 * btrfs_clone() - clone a range from inode file to another
3334 * @src: Inode to clone from
3335 * @inode: Inode to clone to
3336 * @off: Offset within source to start clone from
3337 * @olen: Original length, passed by user, of range to clone
3338 * @olen_aligned: Block-aligned value of olen
3339 * @destoff: Offset within @inode to start clone
3340 * @no_time_update: Whether to update mtime/ctime on the target inode
3342 static int btrfs_clone(struct inode *src, struct inode *inode,
3343 const u64 off, const u64 olen, const u64 olen_aligned,
3344 const u64 destoff, int no_time_update)
3346 struct btrfs_root *root = BTRFS_I(inode)->root;
3347 struct btrfs_path *path = NULL;
3348 struct extent_buffer *leaf;
3349 struct btrfs_trans_handle *trans;
3350 char *buf = NULL;
3351 struct btrfs_key key;
3352 u32 nritems;
3353 int slot;
3354 int ret;
3355 int no_quota;
3356 const u64 len = olen_aligned;
3357 u64 last_disko = 0;
3358 u64 last_dest_end = destoff;
3360 ret = -ENOMEM;
3361 buf = vmalloc(root->nodesize);
3362 if (!buf)
3363 return ret;
3365 path = btrfs_alloc_path();
3366 if (!path) {
3367 vfree(buf);
3368 return ret;
3371 path->reada = 2;
3372 /* clone data */
3373 key.objectid = btrfs_ino(src);
3374 key.type = BTRFS_EXTENT_DATA_KEY;
3375 key.offset = off;
3377 while (1) {
3378 u64 next_key_min_offset = key.offset + 1;
3381 * note the key will change type as we walk through the
3382 * tree.
3384 path->leave_spinning = 1;
3385 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3386 0, 0);
3387 if (ret < 0)
3388 goto out;
3390 * First search, if no extent item that starts at offset off was
3391 * found but the previous item is an extent item, it's possible
3392 * it might overlap our target range, therefore process it.
3394 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3395 btrfs_item_key_to_cpu(path->nodes[0], &key,
3396 path->slots[0] - 1);
3397 if (key.type == BTRFS_EXTENT_DATA_KEY)
3398 path->slots[0]--;
3401 nritems = btrfs_header_nritems(path->nodes[0]);
3402 process_slot:
3403 no_quota = 1;
3404 if (path->slots[0] >= nritems) {
3405 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3406 if (ret < 0)
3407 goto out;
3408 if (ret > 0)
3409 break;
3410 nritems = btrfs_header_nritems(path->nodes[0]);
3412 leaf = path->nodes[0];
3413 slot = path->slots[0];
3415 btrfs_item_key_to_cpu(leaf, &key, slot);
3416 if (key.type > BTRFS_EXTENT_DATA_KEY ||
3417 key.objectid != btrfs_ino(src))
3418 break;
3420 if (key.type == BTRFS_EXTENT_DATA_KEY) {
3421 struct btrfs_file_extent_item *extent;
3422 int type;
3423 u32 size;
3424 struct btrfs_key new_key;
3425 u64 disko = 0, diskl = 0;
3426 u64 datao = 0, datal = 0;
3427 u8 comp;
3428 u64 drop_start;
3430 extent = btrfs_item_ptr(leaf, slot,
3431 struct btrfs_file_extent_item);
3432 comp = btrfs_file_extent_compression(leaf, extent);
3433 type = btrfs_file_extent_type(leaf, extent);
3434 if (type == BTRFS_FILE_EXTENT_REG ||
3435 type == BTRFS_FILE_EXTENT_PREALLOC) {
3436 disko = btrfs_file_extent_disk_bytenr(leaf,
3437 extent);
3438 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3439 extent);
3440 datao = btrfs_file_extent_offset(leaf, extent);
3441 datal = btrfs_file_extent_num_bytes(leaf,
3442 extent);
3443 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3444 /* take upper bound, may be compressed */
3445 datal = btrfs_file_extent_ram_bytes(leaf,
3446 extent);
3450 * The first search might have left us at an extent
3451 * item that ends before our target range's start, can
3452 * happen if we have holes and NO_HOLES feature enabled.
3454 if (key.offset + datal <= off) {
3455 path->slots[0]++;
3456 goto process_slot;
3457 } else if (key.offset >= off + len) {
3458 break;
3460 next_key_min_offset = key.offset + datal;
3461 size = btrfs_item_size_nr(leaf, slot);
3462 read_extent_buffer(leaf, buf,
3463 btrfs_item_ptr_offset(leaf, slot),
3464 size);
3466 btrfs_release_path(path);
3467 path->leave_spinning = 0;
3469 memcpy(&new_key, &key, sizeof(new_key));
3470 new_key.objectid = btrfs_ino(inode);
3471 if (off <= key.offset)
3472 new_key.offset = key.offset + destoff - off;
3473 else
3474 new_key.offset = destoff;
3477 * Deal with a hole that doesn't have an extent item
3478 * that represents it (NO_HOLES feature enabled).
3479 * This hole is either in the middle of the cloning
3480 * range or at the beginning (fully overlaps it or
3481 * partially overlaps it).
3483 if (new_key.offset != last_dest_end)
3484 drop_start = last_dest_end;
3485 else
3486 drop_start = new_key.offset;
3489 * 1 - adjusting old extent (we may have to split it)
3490 * 1 - add new extent
3491 * 1 - inode update
3493 trans = btrfs_start_transaction(root, 3);
3494 if (IS_ERR(trans)) {
3495 ret = PTR_ERR(trans);
3496 goto out;
3499 if (type == BTRFS_FILE_EXTENT_REG ||
3500 type == BTRFS_FILE_EXTENT_PREALLOC) {
3502 * a | --- range to clone ---| b
3503 * | ------------- extent ------------- |
3506 /* subtract range b */
3507 if (key.offset + datal > off + len)
3508 datal = off + len - key.offset;
3510 /* subtract range a */
3511 if (off > key.offset) {
3512 datao += off - key.offset;
3513 datal -= off - key.offset;
3516 ret = btrfs_drop_extents(trans, root, inode,
3517 drop_start,
3518 new_key.offset + datal,
3520 if (ret) {
3521 if (ret != -EOPNOTSUPP)
3522 btrfs_abort_transaction(trans,
3523 root, ret);
3524 btrfs_end_transaction(trans, root);
3525 goto out;
3528 ret = btrfs_insert_empty_item(trans, root, path,
3529 &new_key, size);
3530 if (ret) {
3531 btrfs_abort_transaction(trans, root,
3532 ret);
3533 btrfs_end_transaction(trans, root);
3534 goto out;
3537 leaf = path->nodes[0];
3538 slot = path->slots[0];
3539 write_extent_buffer(leaf, buf,
3540 btrfs_item_ptr_offset(leaf, slot),
3541 size);
3543 extent = btrfs_item_ptr(leaf, slot,
3544 struct btrfs_file_extent_item);
3546 /* disko == 0 means it's a hole */
3547 if (!disko)
3548 datao = 0;
3550 btrfs_set_file_extent_offset(leaf, extent,
3551 datao);
3552 btrfs_set_file_extent_num_bytes(leaf, extent,
3553 datal);
3556 * We need to look up the roots that point at
3557 * this bytenr and see if the new root does. If
3558 * it does not we need to make sure we update
3559 * quotas appropriately.
3561 if (disko && root != BTRFS_I(src)->root &&
3562 disko != last_disko) {
3563 no_quota = check_ref(trans, root,
3564 disko);
3565 if (no_quota < 0) {
3566 btrfs_abort_transaction(trans,
3567 root,
3568 ret);
3569 btrfs_end_transaction(trans,
3570 root);
3571 ret = no_quota;
3572 goto out;
3576 if (disko) {
3577 inode_add_bytes(inode, datal);
3578 ret = btrfs_inc_extent_ref(trans, root,
3579 disko, diskl, 0,
3580 root->root_key.objectid,
3581 btrfs_ino(inode),
3582 new_key.offset - datao,
3583 no_quota);
3584 if (ret) {
3585 btrfs_abort_transaction(trans,
3586 root,
3587 ret);
3588 btrfs_end_transaction(trans,
3589 root);
3590 goto out;
3594 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3595 u64 skip = 0;
3596 u64 trim = 0;
3597 u64 aligned_end = 0;
3600 * Don't copy an inline extent into an offset
3601 * greater than zero. Having an inline extent
3602 * at such an offset results in chaos as btrfs
3603 * isn't prepared for such cases. Just skip
3604 * this case for the same reasons as commented
3605 * at btrfs_ioctl_clone().
3607 if (last_dest_end > 0) {
3608 ret = -EOPNOTSUPP;
3609 btrfs_end_transaction(trans, root);
3610 goto out;
3613 if (off > key.offset) {
3614 skip = off - key.offset;
3615 new_key.offset += skip;
3618 if (key.offset + datal > off + len)
3619 trim = key.offset + datal - (off + len);
3621 if (comp && (skip || trim)) {
3622 ret = -EINVAL;
3623 btrfs_end_transaction(trans, root);
3624 goto out;
3626 size -= skip + trim;
3627 datal -= skip + trim;
3629 aligned_end = ALIGN(new_key.offset + datal,
3630 root->sectorsize);
3631 ret = btrfs_drop_extents(trans, root, inode,
3632 drop_start,
3633 aligned_end,
3635 if (ret) {
3636 if (ret != -EOPNOTSUPP)
3637 btrfs_abort_transaction(trans,
3638 root, ret);
3639 btrfs_end_transaction(trans, root);
3640 goto out;
3643 ret = btrfs_insert_empty_item(trans, root, path,
3644 &new_key, size);
3645 if (ret) {
3646 btrfs_abort_transaction(trans, root,
3647 ret);
3648 btrfs_end_transaction(trans, root);
3649 goto out;
3652 if (skip) {
3653 u32 start =
3654 btrfs_file_extent_calc_inline_size(0);
3655 memmove(buf+start, buf+start+skip,
3656 datal);
3659 leaf = path->nodes[0];
3660 slot = path->slots[0];
3661 write_extent_buffer(leaf, buf,
3662 btrfs_item_ptr_offset(leaf, slot),
3663 size);
3664 inode_add_bytes(inode, datal);
3667 /* If we have an implicit hole (NO_HOLES feature). */
3668 if (drop_start < new_key.offset)
3669 clone_update_extent_map(inode, trans,
3670 NULL, drop_start,
3671 new_key.offset - drop_start);
3673 clone_update_extent_map(inode, trans, path, 0, 0);
3675 btrfs_mark_buffer_dirty(leaf);
3676 btrfs_release_path(path);
3678 last_dest_end = ALIGN(new_key.offset + datal,
3679 root->sectorsize);
3680 ret = clone_finish_inode_update(trans, inode,
3681 last_dest_end,
3682 destoff, olen,
3683 no_time_update);
3684 if (ret)
3685 goto out;
3686 if (new_key.offset + datal >= destoff + len)
3687 break;
3689 btrfs_release_path(path);
3690 key.offset = next_key_min_offset;
3692 ret = 0;
3694 if (last_dest_end < destoff + len) {
3696 * We have an implicit hole (NO_HOLES feature is enabled) that
3697 * fully or partially overlaps our cloning range at its end.
3699 btrfs_release_path(path);
3702 * 1 - remove extent(s)
3703 * 1 - inode update
3705 trans = btrfs_start_transaction(root, 2);
3706 if (IS_ERR(trans)) {
3707 ret = PTR_ERR(trans);
3708 goto out;
3710 ret = btrfs_drop_extents(trans, root, inode,
3711 last_dest_end, destoff + len, 1);
3712 if (ret) {
3713 if (ret != -EOPNOTSUPP)
3714 btrfs_abort_transaction(trans, root, ret);
3715 btrfs_end_transaction(trans, root);
3716 goto out;
3718 clone_update_extent_map(inode, trans, NULL, last_dest_end,
3719 destoff + len - last_dest_end);
3720 ret = clone_finish_inode_update(trans, inode, destoff + len,
3721 destoff, olen, no_time_update);
3724 out:
3725 btrfs_free_path(path);
3726 vfree(buf);
3727 return ret;
3730 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
3731 u64 off, u64 olen, u64 destoff)
3733 struct inode *inode = file_inode(file);
3734 struct btrfs_root *root = BTRFS_I(inode)->root;
3735 struct fd src_file;
3736 struct inode *src;
3737 int ret;
3738 u64 len = olen;
3739 u64 bs = root->fs_info->sb->s_blocksize;
3740 int same_inode = 0;
3743 * TODO:
3744 * - split compressed inline extents. annoying: we need to
3745 * decompress into destination's address_space (the file offset
3746 * may change, so source mapping won't do), then recompress (or
3747 * otherwise reinsert) a subrange.
3749 * - split destination inode's inline extents. The inline extents can
3750 * be either compressed or non-compressed.
3753 /* the destination must be opened for writing */
3754 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
3755 return -EINVAL;
3757 if (btrfs_root_readonly(root))
3758 return -EROFS;
3760 ret = mnt_want_write_file(file);
3761 if (ret)
3762 return ret;
3764 src_file = fdget(srcfd);
3765 if (!src_file.file) {
3766 ret = -EBADF;
3767 goto out_drop_write;
3770 ret = -EXDEV;
3771 if (src_file.file->f_path.mnt != file->f_path.mnt)
3772 goto out_fput;
3774 src = file_inode(src_file.file);
3776 ret = -EINVAL;
3777 if (src == inode)
3778 same_inode = 1;
3780 /* the src must be open for reading */
3781 if (!(src_file.file->f_mode & FMODE_READ))
3782 goto out_fput;
3784 /* don't make the dst file partly checksummed */
3785 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3786 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3787 goto out_fput;
3789 ret = -EISDIR;
3790 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3791 goto out_fput;
3793 ret = -EXDEV;
3794 if (src->i_sb != inode->i_sb)
3795 goto out_fput;
3797 if (!same_inode) {
3798 btrfs_double_inode_lock(src, inode);
3799 } else {
3800 mutex_lock(&src->i_mutex);
3803 /* determine range to clone */
3804 ret = -EINVAL;
3805 if (off + len > src->i_size || off + len < off)
3806 goto out_unlock;
3807 if (len == 0)
3808 olen = len = src->i_size - off;
3809 /* if we extend to eof, continue to block boundary */
3810 if (off + len == src->i_size)
3811 len = ALIGN(src->i_size, bs) - off;
3813 if (len == 0) {
3814 ret = 0;
3815 goto out_unlock;
3818 /* verify the end result is block aligned */
3819 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
3820 !IS_ALIGNED(destoff, bs))
3821 goto out_unlock;
3823 /* verify if ranges are overlapped within the same file */
3824 if (same_inode) {
3825 if (destoff + len > off && destoff < off + len)
3826 goto out_unlock;
3829 if (destoff > inode->i_size) {
3830 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3831 if (ret)
3832 goto out_unlock;
3836 * Lock the target range too. Right after we replace the file extent
3837 * items in the fs tree (which now point to the cloned data), we might
3838 * have a worker replace them with extent items relative to a write
3839 * operation that was issued before this clone operation (i.e. confront
3840 * with inode.c:btrfs_finish_ordered_io).
3842 if (same_inode) {
3843 u64 lock_start = min_t(u64, off, destoff);
3844 u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
3846 lock_extent_range(src, lock_start, lock_len);
3847 } else {
3848 btrfs_double_extent_lock(src, off, inode, destoff, len);
3851 ret = btrfs_clone(src, inode, off, olen, len, destoff, 0);
3853 if (same_inode) {
3854 u64 lock_start = min_t(u64, off, destoff);
3855 u64 lock_end = max_t(u64, off, destoff) + len - 1;
3857 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
3858 } else {
3859 btrfs_double_extent_unlock(src, off, inode, destoff, len);
3862 * Truncate page cache pages so that future reads will see the cloned
3863 * data immediately and not the previous data.
3865 truncate_inode_pages_range(&inode->i_data, destoff,
3866 PAGE_CACHE_ALIGN(destoff + len) - 1);
3867 out_unlock:
3868 if (!same_inode)
3869 btrfs_double_inode_unlock(src, inode);
3870 else
3871 mutex_unlock(&src->i_mutex);
3872 out_fput:
3873 fdput(src_file);
3874 out_drop_write:
3875 mnt_drop_write_file(file);
3876 return ret;
3879 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3881 struct btrfs_ioctl_clone_range_args args;
3883 if (copy_from_user(&args, argp, sizeof(args)))
3884 return -EFAULT;
3885 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
3886 args.src_length, args.dest_offset);
3890 * there are many ways the trans_start and trans_end ioctls can lead
3891 * to deadlocks. They should only be used by applications that
3892 * basically own the machine, and have a very in depth understanding
3893 * of all the possible deadlocks and enospc problems.
3895 static long btrfs_ioctl_trans_start(struct file *file)
3897 struct inode *inode = file_inode(file);
3898 struct btrfs_root *root = BTRFS_I(inode)->root;
3899 struct btrfs_trans_handle *trans;
3900 int ret;
3902 ret = -EPERM;
3903 if (!capable(CAP_SYS_ADMIN))
3904 goto out;
3906 ret = -EINPROGRESS;
3907 if (file->private_data)
3908 goto out;
3910 ret = -EROFS;
3911 if (btrfs_root_readonly(root))
3912 goto out;
3914 ret = mnt_want_write_file(file);
3915 if (ret)
3916 goto out;
3918 atomic_inc(&root->fs_info->open_ioctl_trans);
3920 ret = -ENOMEM;
3921 trans = btrfs_start_ioctl_transaction(root);
3922 if (IS_ERR(trans))
3923 goto out_drop;
3925 file->private_data = trans;
3926 return 0;
3928 out_drop:
3929 atomic_dec(&root->fs_info->open_ioctl_trans);
3930 mnt_drop_write_file(file);
3931 out:
3932 return ret;
3935 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3937 struct inode *inode = file_inode(file);
3938 struct btrfs_root *root = BTRFS_I(inode)->root;
3939 struct btrfs_root *new_root;
3940 struct btrfs_dir_item *di;
3941 struct btrfs_trans_handle *trans;
3942 struct btrfs_path *path;
3943 struct btrfs_key location;
3944 struct btrfs_disk_key disk_key;
3945 u64 objectid = 0;
3946 u64 dir_id;
3947 int ret;
3949 if (!capable(CAP_SYS_ADMIN))
3950 return -EPERM;
3952 ret = mnt_want_write_file(file);
3953 if (ret)
3954 return ret;
3956 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3957 ret = -EFAULT;
3958 goto out;
3961 if (!objectid)
3962 objectid = BTRFS_FS_TREE_OBJECTID;
3964 location.objectid = objectid;
3965 location.type = BTRFS_ROOT_ITEM_KEY;
3966 location.offset = (u64)-1;
3968 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
3969 if (IS_ERR(new_root)) {
3970 ret = PTR_ERR(new_root);
3971 goto out;
3974 path = btrfs_alloc_path();
3975 if (!path) {
3976 ret = -ENOMEM;
3977 goto out;
3979 path->leave_spinning = 1;
3981 trans = btrfs_start_transaction(root, 1);
3982 if (IS_ERR(trans)) {
3983 btrfs_free_path(path);
3984 ret = PTR_ERR(trans);
3985 goto out;
3988 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3989 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
3990 dir_id, "default", 7, 1);
3991 if (IS_ERR_OR_NULL(di)) {
3992 btrfs_free_path(path);
3993 btrfs_end_transaction(trans, root);
3994 btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
3995 "item, this isn't going to work");
3996 ret = -ENOENT;
3997 goto out;
4000 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
4001 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
4002 btrfs_mark_buffer_dirty(path->nodes[0]);
4003 btrfs_free_path(path);
4005 btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
4006 btrfs_end_transaction(trans, root);
4007 out:
4008 mnt_drop_write_file(file);
4009 return ret;
4012 void btrfs_get_block_group_info(struct list_head *groups_list,
4013 struct btrfs_ioctl_space_info *space)
4015 struct btrfs_block_group_cache *block_group;
4017 space->total_bytes = 0;
4018 space->used_bytes = 0;
4019 space->flags = 0;
4020 list_for_each_entry(block_group, groups_list, list) {
4021 space->flags = block_group->flags;
4022 space->total_bytes += block_group->key.offset;
4023 space->used_bytes +=
4024 btrfs_block_group_used(&block_group->item);
4028 static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
4030 struct btrfs_ioctl_space_args space_args;
4031 struct btrfs_ioctl_space_info space;
4032 struct btrfs_ioctl_space_info *dest;
4033 struct btrfs_ioctl_space_info *dest_orig;
4034 struct btrfs_ioctl_space_info __user *user_dest;
4035 struct btrfs_space_info *info;
4036 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
4037 BTRFS_BLOCK_GROUP_SYSTEM,
4038 BTRFS_BLOCK_GROUP_METADATA,
4039 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
4040 int num_types = 4;
4041 int alloc_size;
4042 int ret = 0;
4043 u64 slot_count = 0;
4044 int i, c;
4046 if (copy_from_user(&space_args,
4047 (struct btrfs_ioctl_space_args __user *)arg,
4048 sizeof(space_args)))
4049 return -EFAULT;
4051 for (i = 0; i < num_types; i++) {
4052 struct btrfs_space_info *tmp;
4054 info = NULL;
4055 rcu_read_lock();
4056 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
4057 list) {
4058 if (tmp->flags == types[i]) {
4059 info = tmp;
4060 break;
4063 rcu_read_unlock();
4065 if (!info)
4066 continue;
4068 down_read(&info->groups_sem);
4069 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4070 if (!list_empty(&info->block_groups[c]))
4071 slot_count++;
4073 up_read(&info->groups_sem);
4077 * Global block reserve, exported as a space_info
4079 slot_count++;
4081 /* space_slots == 0 means they are asking for a count */
4082 if (space_args.space_slots == 0) {
4083 space_args.total_spaces = slot_count;
4084 goto out;
4087 slot_count = min_t(u64, space_args.space_slots, slot_count);
4089 alloc_size = sizeof(*dest) * slot_count;
4091 /* we generally have at most 6 or so space infos, one for each raid
4092 * level. So, a whole page should be more than enough for everyone
4094 if (alloc_size > PAGE_CACHE_SIZE)
4095 return -ENOMEM;
4097 space_args.total_spaces = 0;
4098 dest = kmalloc(alloc_size, GFP_NOFS);
4099 if (!dest)
4100 return -ENOMEM;
4101 dest_orig = dest;
4103 /* now we have a buffer to copy into */
4104 for (i = 0; i < num_types; i++) {
4105 struct btrfs_space_info *tmp;
4107 if (!slot_count)
4108 break;
4110 info = NULL;
4111 rcu_read_lock();
4112 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
4113 list) {
4114 if (tmp->flags == types[i]) {
4115 info = tmp;
4116 break;
4119 rcu_read_unlock();
4121 if (!info)
4122 continue;
4123 down_read(&info->groups_sem);
4124 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4125 if (!list_empty(&info->block_groups[c])) {
4126 btrfs_get_block_group_info(
4127 &info->block_groups[c], &space);
4128 memcpy(dest, &space, sizeof(space));
4129 dest++;
4130 space_args.total_spaces++;
4131 slot_count--;
4133 if (!slot_count)
4134 break;
4136 up_read(&info->groups_sem);
4140 * Add global block reserve
4142 if (slot_count) {
4143 struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv;
4145 spin_lock(&block_rsv->lock);
4146 space.total_bytes = block_rsv->size;
4147 space.used_bytes = block_rsv->size - block_rsv->reserved;
4148 spin_unlock(&block_rsv->lock);
4149 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
4150 memcpy(dest, &space, sizeof(space));
4151 space_args.total_spaces++;
4154 user_dest = (struct btrfs_ioctl_space_info __user *)
4155 (arg + sizeof(struct btrfs_ioctl_space_args));
4157 if (copy_to_user(user_dest, dest_orig, alloc_size))
4158 ret = -EFAULT;
4160 kfree(dest_orig);
4161 out:
4162 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4163 ret = -EFAULT;
4165 return ret;
4169 * there are many ways the trans_start and trans_end ioctls can lead
4170 * to deadlocks. They should only be used by applications that
4171 * basically own the machine, and have a very in depth understanding
4172 * of all the possible deadlocks and enospc problems.
4174 long btrfs_ioctl_trans_end(struct file *file)
4176 struct inode *inode = file_inode(file);
4177 struct btrfs_root *root = BTRFS_I(inode)->root;
4178 struct btrfs_trans_handle *trans;
4180 trans = file->private_data;
4181 if (!trans)
4182 return -EINVAL;
4183 file->private_data = NULL;
4185 btrfs_end_transaction(trans, root);
4187 atomic_dec(&root->fs_info->open_ioctl_trans);
4189 mnt_drop_write_file(file);
4190 return 0;
4193 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4194 void __user *argp)
4196 struct btrfs_trans_handle *trans;
4197 u64 transid;
4198 int ret;
4200 trans = btrfs_attach_transaction_barrier(root);
4201 if (IS_ERR(trans)) {
4202 if (PTR_ERR(trans) != -ENOENT)
4203 return PTR_ERR(trans);
4205 /* No running transaction, don't bother */
4206 transid = root->fs_info->last_trans_committed;
4207 goto out;
4209 transid = trans->transid;
4210 ret = btrfs_commit_transaction_async(trans, root, 0);
4211 if (ret) {
4212 btrfs_end_transaction(trans, root);
4213 return ret;
4215 out:
4216 if (argp)
4217 if (copy_to_user(argp, &transid, sizeof(transid)))
4218 return -EFAULT;
4219 return 0;
4222 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
4223 void __user *argp)
4225 u64 transid;
4227 if (argp) {
4228 if (copy_from_user(&transid, argp, sizeof(transid)))
4229 return -EFAULT;
4230 } else {
4231 transid = 0; /* current trans */
4233 return btrfs_wait_for_commit(root, transid);
4236 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4238 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4239 struct btrfs_ioctl_scrub_args *sa;
4240 int ret;
4242 if (!capable(CAP_SYS_ADMIN))
4243 return -EPERM;
4245 sa = memdup_user(arg, sizeof(*sa));
4246 if (IS_ERR(sa))
4247 return PTR_ERR(sa);
4249 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4250 ret = mnt_want_write_file(file);
4251 if (ret)
4252 goto out;
4255 ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
4256 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4259 if (copy_to_user(arg, sa, sizeof(*sa)))
4260 ret = -EFAULT;
4262 if (!(sa->flags & BTRFS_SCRUB_READONLY))
4263 mnt_drop_write_file(file);
4264 out:
4265 kfree(sa);
4266 return ret;
4269 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
4271 if (!capable(CAP_SYS_ADMIN))
4272 return -EPERM;
4274 return btrfs_scrub_cancel(root->fs_info);
4277 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
4278 void __user *arg)
4280 struct btrfs_ioctl_scrub_args *sa;
4281 int ret;
4283 if (!capable(CAP_SYS_ADMIN))
4284 return -EPERM;
4286 sa = memdup_user(arg, sizeof(*sa));
4287 if (IS_ERR(sa))
4288 return PTR_ERR(sa);
4290 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
4292 if (copy_to_user(arg, sa, sizeof(*sa)))
4293 ret = -EFAULT;
4295 kfree(sa);
4296 return ret;
4299 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
4300 void __user *arg)
4302 struct btrfs_ioctl_get_dev_stats *sa;
4303 int ret;
4305 sa = memdup_user(arg, sizeof(*sa));
4306 if (IS_ERR(sa))
4307 return PTR_ERR(sa);
4309 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4310 kfree(sa);
4311 return -EPERM;
4314 ret = btrfs_get_dev_stats(root, sa);
4316 if (copy_to_user(arg, sa, sizeof(*sa)))
4317 ret = -EFAULT;
4319 kfree(sa);
4320 return ret;
4323 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
4325 struct btrfs_ioctl_dev_replace_args *p;
4326 int ret;
4328 if (!capable(CAP_SYS_ADMIN))
4329 return -EPERM;
4331 p = memdup_user(arg, sizeof(*p));
4332 if (IS_ERR(p))
4333 return PTR_ERR(p);
4335 switch (p->cmd) {
4336 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4337 if (root->fs_info->sb->s_flags & MS_RDONLY) {
4338 ret = -EROFS;
4339 goto out;
4341 if (atomic_xchg(
4342 &root->fs_info->mutually_exclusive_operation_running,
4343 1)) {
4344 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4345 } else {
4346 ret = btrfs_dev_replace_start(root, p);
4347 atomic_set(
4348 &root->fs_info->mutually_exclusive_operation_running,
4351 break;
4352 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4353 btrfs_dev_replace_status(root->fs_info, p);
4354 ret = 0;
4355 break;
4356 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4357 ret = btrfs_dev_replace_cancel(root->fs_info, p);
4358 break;
4359 default:
4360 ret = -EINVAL;
4361 break;
4364 if (copy_to_user(arg, p, sizeof(*p)))
4365 ret = -EFAULT;
4366 out:
4367 kfree(p);
4368 return ret;
4371 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4373 int ret = 0;
4374 int i;
4375 u64 rel_ptr;
4376 int size;
4377 struct btrfs_ioctl_ino_path_args *ipa = NULL;
4378 struct inode_fs_paths *ipath = NULL;
4379 struct btrfs_path *path;
4381 if (!capable(CAP_DAC_READ_SEARCH))
4382 return -EPERM;
4384 path = btrfs_alloc_path();
4385 if (!path) {
4386 ret = -ENOMEM;
4387 goto out;
4390 ipa = memdup_user(arg, sizeof(*ipa));
4391 if (IS_ERR(ipa)) {
4392 ret = PTR_ERR(ipa);
4393 ipa = NULL;
4394 goto out;
4397 size = min_t(u32, ipa->size, 4096);
4398 ipath = init_ipath(size, root, path);
4399 if (IS_ERR(ipath)) {
4400 ret = PTR_ERR(ipath);
4401 ipath = NULL;
4402 goto out;
4405 ret = paths_from_inode(ipa->inum, ipath);
4406 if (ret < 0)
4407 goto out;
4409 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4410 rel_ptr = ipath->fspath->val[i] -
4411 (u64)(unsigned long)ipath->fspath->val;
4412 ipath->fspath->val[i] = rel_ptr;
4415 ret = copy_to_user((void *)(unsigned long)ipa->fspath,
4416 (void *)(unsigned long)ipath->fspath, size);
4417 if (ret) {
4418 ret = -EFAULT;
4419 goto out;
4422 out:
4423 btrfs_free_path(path);
4424 free_ipath(ipath);
4425 kfree(ipa);
4427 return ret;
4430 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4432 struct btrfs_data_container *inodes = ctx;
4433 const size_t c = 3 * sizeof(u64);
4435 if (inodes->bytes_left >= c) {
4436 inodes->bytes_left -= c;
4437 inodes->val[inodes->elem_cnt] = inum;
4438 inodes->val[inodes->elem_cnt + 1] = offset;
4439 inodes->val[inodes->elem_cnt + 2] = root;
4440 inodes->elem_cnt += 3;
4441 } else {
4442 inodes->bytes_missing += c - inodes->bytes_left;
4443 inodes->bytes_left = 0;
4444 inodes->elem_missed += 3;
4447 return 0;
4450 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
4451 void __user *arg)
4453 int ret = 0;
4454 int size;
4455 struct btrfs_ioctl_logical_ino_args *loi;
4456 struct btrfs_data_container *inodes = NULL;
4457 struct btrfs_path *path = NULL;
4459 if (!capable(CAP_SYS_ADMIN))
4460 return -EPERM;
4462 loi = memdup_user(arg, sizeof(*loi));
4463 if (IS_ERR(loi)) {
4464 ret = PTR_ERR(loi);
4465 loi = NULL;
4466 goto out;
4469 path = btrfs_alloc_path();
4470 if (!path) {
4471 ret = -ENOMEM;
4472 goto out;
4475 size = min_t(u32, loi->size, 64 * 1024);
4476 inodes = init_data_container(size);
4477 if (IS_ERR(inodes)) {
4478 ret = PTR_ERR(inodes);
4479 inodes = NULL;
4480 goto out;
4483 ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
4484 build_ino_list, inodes);
4485 if (ret == -EINVAL)
4486 ret = -ENOENT;
4487 if (ret < 0)
4488 goto out;
4490 ret = copy_to_user((void *)(unsigned long)loi->inodes,
4491 (void *)(unsigned long)inodes, size);
4492 if (ret)
4493 ret = -EFAULT;
4495 out:
4496 btrfs_free_path(path);
4497 vfree(inodes);
4498 kfree(loi);
4500 return ret;
4503 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
4504 struct btrfs_ioctl_balance_args *bargs)
4506 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4508 bargs->flags = bctl->flags;
4510 if (atomic_read(&fs_info->balance_running))
4511 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4512 if (atomic_read(&fs_info->balance_pause_req))
4513 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4514 if (atomic_read(&fs_info->balance_cancel_req))
4515 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4517 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4518 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4519 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4521 if (lock) {
4522 spin_lock(&fs_info->balance_lock);
4523 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4524 spin_unlock(&fs_info->balance_lock);
4525 } else {
4526 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4530 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4532 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4533 struct btrfs_fs_info *fs_info = root->fs_info;
4534 struct btrfs_ioctl_balance_args *bargs;
4535 struct btrfs_balance_control *bctl;
4536 bool need_unlock; /* for mut. excl. ops lock */
4537 int ret;
4539 if (!capable(CAP_SYS_ADMIN))
4540 return -EPERM;
4542 ret = mnt_want_write_file(file);
4543 if (ret)
4544 return ret;
4546 again:
4547 if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
4548 mutex_lock(&fs_info->volume_mutex);
4549 mutex_lock(&fs_info->balance_mutex);
4550 need_unlock = true;
4551 goto locked;
4555 * mut. excl. ops lock is locked. Three possibilites:
4556 * (1) some other op is running
4557 * (2) balance is running
4558 * (3) balance is paused -- special case (think resume)
4560 mutex_lock(&fs_info->balance_mutex);
4561 if (fs_info->balance_ctl) {
4562 /* this is either (2) or (3) */
4563 if (!atomic_read(&fs_info->balance_running)) {
4564 mutex_unlock(&fs_info->balance_mutex);
4565 if (!mutex_trylock(&fs_info->volume_mutex))
4566 goto again;
4567 mutex_lock(&fs_info->balance_mutex);
4569 if (fs_info->balance_ctl &&
4570 !atomic_read(&fs_info->balance_running)) {
4571 /* this is (3) */
4572 need_unlock = false;
4573 goto locked;
4576 mutex_unlock(&fs_info->balance_mutex);
4577 mutex_unlock(&fs_info->volume_mutex);
4578 goto again;
4579 } else {
4580 /* this is (2) */
4581 mutex_unlock(&fs_info->balance_mutex);
4582 ret = -EINPROGRESS;
4583 goto out;
4585 } else {
4586 /* this is (1) */
4587 mutex_unlock(&fs_info->balance_mutex);
4588 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4589 goto out;
4592 locked:
4593 BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4595 if (arg) {
4596 bargs = memdup_user(arg, sizeof(*bargs));
4597 if (IS_ERR(bargs)) {
4598 ret = PTR_ERR(bargs);
4599 goto out_unlock;
4602 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4603 if (!fs_info->balance_ctl) {
4604 ret = -ENOTCONN;
4605 goto out_bargs;
4608 bctl = fs_info->balance_ctl;
4609 spin_lock(&fs_info->balance_lock);
4610 bctl->flags |= BTRFS_BALANCE_RESUME;
4611 spin_unlock(&fs_info->balance_lock);
4613 goto do_balance;
4615 } else {
4616 bargs = NULL;
4619 if (fs_info->balance_ctl) {
4620 ret = -EINPROGRESS;
4621 goto out_bargs;
4624 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
4625 if (!bctl) {
4626 ret = -ENOMEM;
4627 goto out_bargs;
4630 bctl->fs_info = fs_info;
4631 if (arg) {
4632 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4633 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4634 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4636 bctl->flags = bargs->flags;
4637 } else {
4638 /* balance everything - no filters */
4639 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4642 do_balance:
4644 * Ownership of bctl and mutually_exclusive_operation_running
4645 * goes to to btrfs_balance. bctl is freed in __cancel_balance,
4646 * or, if restriper was paused all the way until unmount, in
4647 * free_fs_info. mutually_exclusive_operation_running is
4648 * cleared in __cancel_balance.
4650 need_unlock = false;
4652 ret = btrfs_balance(bctl, bargs);
4654 if (arg) {
4655 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4656 ret = -EFAULT;
4659 out_bargs:
4660 kfree(bargs);
4661 out_unlock:
4662 mutex_unlock(&fs_info->balance_mutex);
4663 mutex_unlock(&fs_info->volume_mutex);
4664 if (need_unlock)
4665 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
4666 out:
4667 mnt_drop_write_file(file);
4668 return ret;
4671 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
4673 if (!capable(CAP_SYS_ADMIN))
4674 return -EPERM;
4676 switch (cmd) {
4677 case BTRFS_BALANCE_CTL_PAUSE:
4678 return btrfs_pause_balance(root->fs_info);
4679 case BTRFS_BALANCE_CTL_CANCEL:
4680 return btrfs_cancel_balance(root->fs_info);
4683 return -EINVAL;
4686 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
4687 void __user *arg)
4689 struct btrfs_fs_info *fs_info = root->fs_info;
4690 struct btrfs_ioctl_balance_args *bargs;
4691 int ret = 0;
4693 if (!capable(CAP_SYS_ADMIN))
4694 return -EPERM;
4696 mutex_lock(&fs_info->balance_mutex);
4697 if (!fs_info->balance_ctl) {
4698 ret = -ENOTCONN;
4699 goto out;
4702 bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
4703 if (!bargs) {
4704 ret = -ENOMEM;
4705 goto out;
4708 update_ioctl_balance_args(fs_info, 1, bargs);
4710 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4711 ret = -EFAULT;
4713 kfree(bargs);
4714 out:
4715 mutex_unlock(&fs_info->balance_mutex);
4716 return ret;
4719 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4721 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4722 struct btrfs_ioctl_quota_ctl_args *sa;
4723 struct btrfs_trans_handle *trans = NULL;
4724 int ret;
4725 int err;
4727 if (!capable(CAP_SYS_ADMIN))
4728 return -EPERM;
4730 ret = mnt_want_write_file(file);
4731 if (ret)
4732 return ret;
4734 sa = memdup_user(arg, sizeof(*sa));
4735 if (IS_ERR(sa)) {
4736 ret = PTR_ERR(sa);
4737 goto drop_write;
4740 down_write(&root->fs_info->subvol_sem);
4741 trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
4742 if (IS_ERR(trans)) {
4743 ret = PTR_ERR(trans);
4744 goto out;
4747 switch (sa->cmd) {
4748 case BTRFS_QUOTA_CTL_ENABLE:
4749 ret = btrfs_quota_enable(trans, root->fs_info);
4750 break;
4751 case BTRFS_QUOTA_CTL_DISABLE:
4752 ret = btrfs_quota_disable(trans, root->fs_info);
4753 break;
4754 default:
4755 ret = -EINVAL;
4756 break;
4759 err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
4760 if (err && !ret)
4761 ret = err;
4762 out:
4763 kfree(sa);
4764 up_write(&root->fs_info->subvol_sem);
4765 drop_write:
4766 mnt_drop_write_file(file);
4767 return ret;
4770 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4772 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4773 struct btrfs_ioctl_qgroup_assign_args *sa;
4774 struct btrfs_trans_handle *trans;
4775 int ret;
4776 int err;
4778 if (!capable(CAP_SYS_ADMIN))
4779 return -EPERM;
4781 ret = mnt_want_write_file(file);
4782 if (ret)
4783 return ret;
4785 sa = memdup_user(arg, sizeof(*sa));
4786 if (IS_ERR(sa)) {
4787 ret = PTR_ERR(sa);
4788 goto drop_write;
4791 trans = btrfs_join_transaction(root);
4792 if (IS_ERR(trans)) {
4793 ret = PTR_ERR(trans);
4794 goto out;
4797 /* FIXME: check if the IDs really exist */
4798 if (sa->assign) {
4799 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
4800 sa->src, sa->dst);
4801 } else {
4802 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
4803 sa->src, sa->dst);
4806 /* update qgroup status and info */
4807 err = btrfs_run_qgroups(trans, root->fs_info);
4808 if (err < 0)
4809 btrfs_error(root->fs_info, ret,
4810 "failed to update qgroup status and info\n");
4811 err = btrfs_end_transaction(trans, root);
4812 if (err && !ret)
4813 ret = err;
4815 out:
4816 kfree(sa);
4817 drop_write:
4818 mnt_drop_write_file(file);
4819 return ret;
4822 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4824 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4825 struct btrfs_ioctl_qgroup_create_args *sa;
4826 struct btrfs_trans_handle *trans;
4827 int ret;
4828 int err;
4830 if (!capable(CAP_SYS_ADMIN))
4831 return -EPERM;
4833 ret = mnt_want_write_file(file);
4834 if (ret)
4835 return ret;
4837 sa = memdup_user(arg, sizeof(*sa));
4838 if (IS_ERR(sa)) {
4839 ret = PTR_ERR(sa);
4840 goto drop_write;
4843 if (!sa->qgroupid) {
4844 ret = -EINVAL;
4845 goto out;
4848 trans = btrfs_join_transaction(root);
4849 if (IS_ERR(trans)) {
4850 ret = PTR_ERR(trans);
4851 goto out;
4854 /* FIXME: check if the IDs really exist */
4855 if (sa->create) {
4856 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid);
4857 } else {
4858 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
4861 err = btrfs_end_transaction(trans, root);
4862 if (err && !ret)
4863 ret = err;
4865 out:
4866 kfree(sa);
4867 drop_write:
4868 mnt_drop_write_file(file);
4869 return ret;
4872 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4874 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4875 struct btrfs_ioctl_qgroup_limit_args *sa;
4876 struct btrfs_trans_handle *trans;
4877 int ret;
4878 int err;
4879 u64 qgroupid;
4881 if (!capable(CAP_SYS_ADMIN))
4882 return -EPERM;
4884 ret = mnt_want_write_file(file);
4885 if (ret)
4886 return ret;
4888 sa = memdup_user(arg, sizeof(*sa));
4889 if (IS_ERR(sa)) {
4890 ret = PTR_ERR(sa);
4891 goto drop_write;
4894 trans = btrfs_join_transaction(root);
4895 if (IS_ERR(trans)) {
4896 ret = PTR_ERR(trans);
4897 goto out;
4900 qgroupid = sa->qgroupid;
4901 if (!qgroupid) {
4902 /* take the current subvol as qgroup */
4903 qgroupid = root->root_key.objectid;
4906 /* FIXME: check if the IDs really exist */
4907 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
4909 err = btrfs_end_transaction(trans, root);
4910 if (err && !ret)
4911 ret = err;
4913 out:
4914 kfree(sa);
4915 drop_write:
4916 mnt_drop_write_file(file);
4917 return ret;
4920 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4922 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4923 struct btrfs_ioctl_quota_rescan_args *qsa;
4924 int ret;
4926 if (!capable(CAP_SYS_ADMIN))
4927 return -EPERM;
4929 ret = mnt_want_write_file(file);
4930 if (ret)
4931 return ret;
4933 qsa = memdup_user(arg, sizeof(*qsa));
4934 if (IS_ERR(qsa)) {
4935 ret = PTR_ERR(qsa);
4936 goto drop_write;
4939 if (qsa->flags) {
4940 ret = -EINVAL;
4941 goto out;
4944 ret = btrfs_qgroup_rescan(root->fs_info);
4946 out:
4947 kfree(qsa);
4948 drop_write:
4949 mnt_drop_write_file(file);
4950 return ret;
4953 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
4955 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4956 struct btrfs_ioctl_quota_rescan_args *qsa;
4957 int ret = 0;
4959 if (!capable(CAP_SYS_ADMIN))
4960 return -EPERM;
4962 qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
4963 if (!qsa)
4964 return -ENOMEM;
4966 if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4967 qsa->flags = 1;
4968 qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
4971 if (copy_to_user(arg, qsa, sizeof(*qsa)))
4972 ret = -EFAULT;
4974 kfree(qsa);
4975 return ret;
4978 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
4980 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4982 if (!capable(CAP_SYS_ADMIN))
4983 return -EPERM;
4985 return btrfs_qgroup_wait_for_completion(root->fs_info);
4988 static long _btrfs_ioctl_set_received_subvol(struct file *file,
4989 struct btrfs_ioctl_received_subvol_args *sa)
4991 struct inode *inode = file_inode(file);
4992 struct btrfs_root *root = BTRFS_I(inode)->root;
4993 struct btrfs_root_item *root_item = &root->root_item;
4994 struct btrfs_trans_handle *trans;
4995 struct timespec ct = CURRENT_TIME;
4996 int ret = 0;
4997 int received_uuid_changed;
4999 if (!inode_owner_or_capable(inode))
5000 return -EPERM;
5002 ret = mnt_want_write_file(file);
5003 if (ret < 0)
5004 return ret;
5006 down_write(&root->fs_info->subvol_sem);
5008 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
5009 ret = -EINVAL;
5010 goto out;
5013 if (btrfs_root_readonly(root)) {
5014 ret = -EROFS;
5015 goto out;
5019 * 1 - root item
5020 * 2 - uuid items (received uuid + subvol uuid)
5022 trans = btrfs_start_transaction(root, 3);
5023 if (IS_ERR(trans)) {
5024 ret = PTR_ERR(trans);
5025 trans = NULL;
5026 goto out;
5029 sa->rtransid = trans->transid;
5030 sa->rtime.sec = ct.tv_sec;
5031 sa->rtime.nsec = ct.tv_nsec;
5033 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
5034 BTRFS_UUID_SIZE);
5035 if (received_uuid_changed &&
5036 !btrfs_is_empty_uuid(root_item->received_uuid))
5037 btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
5038 root_item->received_uuid,
5039 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5040 root->root_key.objectid);
5041 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
5042 btrfs_set_root_stransid(root_item, sa->stransid);
5043 btrfs_set_root_rtransid(root_item, sa->rtransid);
5044 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
5045 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
5046 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
5047 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
5049 ret = btrfs_update_root(trans, root->fs_info->tree_root,
5050 &root->root_key, &root->root_item);
5051 if (ret < 0) {
5052 btrfs_end_transaction(trans, root);
5053 goto out;
5055 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
5056 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
5057 sa->uuid,
5058 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5059 root->root_key.objectid);
5060 if (ret < 0 && ret != -EEXIST) {
5061 btrfs_abort_transaction(trans, root, ret);
5062 goto out;
5065 ret = btrfs_commit_transaction(trans, root);
5066 if (ret < 0) {
5067 btrfs_abort_transaction(trans, root, ret);
5068 goto out;
5071 out:
5072 up_write(&root->fs_info->subvol_sem);
5073 mnt_drop_write_file(file);
5074 return ret;
5077 #ifdef CONFIG_64BIT
5078 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
5079 void __user *arg)
5081 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
5082 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
5083 int ret = 0;
5085 args32 = memdup_user(arg, sizeof(*args32));
5086 if (IS_ERR(args32)) {
5087 ret = PTR_ERR(args32);
5088 args32 = NULL;
5089 goto out;
5092 args64 = kmalloc(sizeof(*args64), GFP_NOFS);
5093 if (!args64) {
5094 ret = -ENOMEM;
5095 goto out;
5098 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
5099 args64->stransid = args32->stransid;
5100 args64->rtransid = args32->rtransid;
5101 args64->stime.sec = args32->stime.sec;
5102 args64->stime.nsec = args32->stime.nsec;
5103 args64->rtime.sec = args32->rtime.sec;
5104 args64->rtime.nsec = args32->rtime.nsec;
5105 args64->flags = args32->flags;
5107 ret = _btrfs_ioctl_set_received_subvol(file, args64);
5108 if (ret)
5109 goto out;
5111 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
5112 args32->stransid = args64->stransid;
5113 args32->rtransid = args64->rtransid;
5114 args32->stime.sec = args64->stime.sec;
5115 args32->stime.nsec = args64->stime.nsec;
5116 args32->rtime.sec = args64->rtime.sec;
5117 args32->rtime.nsec = args64->rtime.nsec;
5118 args32->flags = args64->flags;
5120 ret = copy_to_user(arg, args32, sizeof(*args32));
5121 if (ret)
5122 ret = -EFAULT;
5124 out:
5125 kfree(args32);
5126 kfree(args64);
5127 return ret;
5129 #endif
5131 static long btrfs_ioctl_set_received_subvol(struct file *file,
5132 void __user *arg)
5134 struct btrfs_ioctl_received_subvol_args *sa = NULL;
5135 int ret = 0;
5137 sa = memdup_user(arg, sizeof(*sa));
5138 if (IS_ERR(sa)) {
5139 ret = PTR_ERR(sa);
5140 sa = NULL;
5141 goto out;
5144 ret = _btrfs_ioctl_set_received_subvol(file, sa);
5146 if (ret)
5147 goto out;
5149 ret = copy_to_user(arg, sa, sizeof(*sa));
5150 if (ret)
5151 ret = -EFAULT;
5153 out:
5154 kfree(sa);
5155 return ret;
5158 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
5160 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5161 size_t len;
5162 int ret;
5163 char label[BTRFS_LABEL_SIZE];
5165 spin_lock(&root->fs_info->super_lock);
5166 memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5167 spin_unlock(&root->fs_info->super_lock);
5169 len = strnlen(label, BTRFS_LABEL_SIZE);
5171 if (len == BTRFS_LABEL_SIZE) {
5172 btrfs_warn(root->fs_info,
5173 "label is too long, return the first %zu bytes", --len);
5176 ret = copy_to_user(arg, label, len);
5178 return ret ? -EFAULT : 0;
5181 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5183 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5184 struct btrfs_super_block *super_block = root->fs_info->super_copy;
5185 struct btrfs_trans_handle *trans;
5186 char label[BTRFS_LABEL_SIZE];
5187 int ret;
5189 if (!capable(CAP_SYS_ADMIN))
5190 return -EPERM;
5192 if (copy_from_user(label, arg, sizeof(label)))
5193 return -EFAULT;
5195 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5196 btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
5197 BTRFS_LABEL_SIZE - 1);
5198 return -EINVAL;
5201 ret = mnt_want_write_file(file);
5202 if (ret)
5203 return ret;
5205 trans = btrfs_start_transaction(root, 0);
5206 if (IS_ERR(trans)) {
5207 ret = PTR_ERR(trans);
5208 goto out_unlock;
5211 spin_lock(&root->fs_info->super_lock);
5212 strcpy(super_block->label, label);
5213 spin_unlock(&root->fs_info->super_lock);
5214 ret = btrfs_commit_transaction(trans, root);
5216 out_unlock:
5217 mnt_drop_write_file(file);
5218 return ret;
5221 #define INIT_FEATURE_FLAGS(suffix) \
5222 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5223 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5224 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5226 static int btrfs_ioctl_get_supported_features(struct file *file,
5227 void __user *arg)
5229 static struct btrfs_ioctl_feature_flags features[3] = {
5230 INIT_FEATURE_FLAGS(SUPP),
5231 INIT_FEATURE_FLAGS(SAFE_SET),
5232 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5235 if (copy_to_user(arg, &features, sizeof(features)))
5236 return -EFAULT;
5238 return 0;
5241 static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5243 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5244 struct btrfs_super_block *super_block = root->fs_info->super_copy;
5245 struct btrfs_ioctl_feature_flags features;
5247 features.compat_flags = btrfs_super_compat_flags(super_block);
5248 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5249 features.incompat_flags = btrfs_super_incompat_flags(super_block);
5251 if (copy_to_user(arg, &features, sizeof(features)))
5252 return -EFAULT;
5254 return 0;
5257 static int check_feature_bits(struct btrfs_root *root,
5258 enum btrfs_feature_set set,
5259 u64 change_mask, u64 flags, u64 supported_flags,
5260 u64 safe_set, u64 safe_clear)
5262 const char *type = btrfs_feature_set_names[set];
5263 char *names;
5264 u64 disallowed, unsupported;
5265 u64 set_mask = flags & change_mask;
5266 u64 clear_mask = ~flags & change_mask;
5268 unsupported = set_mask & ~supported_flags;
5269 if (unsupported) {
5270 names = btrfs_printable_features(set, unsupported);
5271 if (names) {
5272 btrfs_warn(root->fs_info,
5273 "this kernel does not support the %s feature bit%s",
5274 names, strchr(names, ',') ? "s" : "");
5275 kfree(names);
5276 } else
5277 btrfs_warn(root->fs_info,
5278 "this kernel does not support %s bits 0x%llx",
5279 type, unsupported);
5280 return -EOPNOTSUPP;
5283 disallowed = set_mask & ~safe_set;
5284 if (disallowed) {
5285 names = btrfs_printable_features(set, disallowed);
5286 if (names) {
5287 btrfs_warn(root->fs_info,
5288 "can't set the %s feature bit%s while mounted",
5289 names, strchr(names, ',') ? "s" : "");
5290 kfree(names);
5291 } else
5292 btrfs_warn(root->fs_info,
5293 "can't set %s bits 0x%llx while mounted",
5294 type, disallowed);
5295 return -EPERM;
5298 disallowed = clear_mask & ~safe_clear;
5299 if (disallowed) {
5300 names = btrfs_printable_features(set, disallowed);
5301 if (names) {
5302 btrfs_warn(root->fs_info,
5303 "can't clear the %s feature bit%s while mounted",
5304 names, strchr(names, ',') ? "s" : "");
5305 kfree(names);
5306 } else
5307 btrfs_warn(root->fs_info,
5308 "can't clear %s bits 0x%llx while mounted",
5309 type, disallowed);
5310 return -EPERM;
5313 return 0;
5316 #define check_feature(root, change_mask, flags, mask_base) \
5317 check_feature_bits(root, FEAT_##mask_base, change_mask, flags, \
5318 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
5319 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
5320 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5322 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5324 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5325 struct btrfs_super_block *super_block = root->fs_info->super_copy;
5326 struct btrfs_ioctl_feature_flags flags[2];
5327 struct btrfs_trans_handle *trans;
5328 u64 newflags;
5329 int ret;
5331 if (!capable(CAP_SYS_ADMIN))
5332 return -EPERM;
5334 if (copy_from_user(flags, arg, sizeof(flags)))
5335 return -EFAULT;
5337 /* Nothing to do */
5338 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5339 !flags[0].incompat_flags)
5340 return 0;
5342 ret = check_feature(root, flags[0].compat_flags,
5343 flags[1].compat_flags, COMPAT);
5344 if (ret)
5345 return ret;
5347 ret = check_feature(root, flags[0].compat_ro_flags,
5348 flags[1].compat_ro_flags, COMPAT_RO);
5349 if (ret)
5350 return ret;
5352 ret = check_feature(root, flags[0].incompat_flags,
5353 flags[1].incompat_flags, INCOMPAT);
5354 if (ret)
5355 return ret;
5357 trans = btrfs_start_transaction(root, 0);
5358 if (IS_ERR(trans))
5359 return PTR_ERR(trans);
5361 spin_lock(&root->fs_info->super_lock);
5362 newflags = btrfs_super_compat_flags(super_block);
5363 newflags |= flags[0].compat_flags & flags[1].compat_flags;
5364 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5365 btrfs_set_super_compat_flags(super_block, newflags);
5367 newflags = btrfs_super_compat_ro_flags(super_block);
5368 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5369 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5370 btrfs_set_super_compat_ro_flags(super_block, newflags);
5372 newflags = btrfs_super_incompat_flags(super_block);
5373 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5374 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5375 btrfs_set_super_incompat_flags(super_block, newflags);
5376 spin_unlock(&root->fs_info->super_lock);
5378 return btrfs_commit_transaction(trans, root);
5381 long btrfs_ioctl(struct file *file, unsigned int
5382 cmd, unsigned long arg)
5384 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5385 void __user *argp = (void __user *)arg;
5387 switch (cmd) {
5388 case FS_IOC_GETFLAGS:
5389 return btrfs_ioctl_getflags(file, argp);
5390 case FS_IOC_SETFLAGS:
5391 return btrfs_ioctl_setflags(file, argp);
5392 case FS_IOC_GETVERSION:
5393 return btrfs_ioctl_getversion(file, argp);
5394 case FITRIM:
5395 return btrfs_ioctl_fitrim(file, argp);
5396 case BTRFS_IOC_SNAP_CREATE:
5397 return btrfs_ioctl_snap_create(file, argp, 0);
5398 case BTRFS_IOC_SNAP_CREATE_V2:
5399 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5400 case BTRFS_IOC_SUBVOL_CREATE:
5401 return btrfs_ioctl_snap_create(file, argp, 1);
5402 case BTRFS_IOC_SUBVOL_CREATE_V2:
5403 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5404 case BTRFS_IOC_SNAP_DESTROY:
5405 return btrfs_ioctl_snap_destroy(file, argp);
5406 case BTRFS_IOC_SUBVOL_GETFLAGS:
5407 return btrfs_ioctl_subvol_getflags(file, argp);
5408 case BTRFS_IOC_SUBVOL_SETFLAGS:
5409 return btrfs_ioctl_subvol_setflags(file, argp);
5410 case BTRFS_IOC_DEFAULT_SUBVOL:
5411 return btrfs_ioctl_default_subvol(file, argp);
5412 case BTRFS_IOC_DEFRAG:
5413 return btrfs_ioctl_defrag(file, NULL);
5414 case BTRFS_IOC_DEFRAG_RANGE:
5415 return btrfs_ioctl_defrag(file, argp);
5416 case BTRFS_IOC_RESIZE:
5417 return btrfs_ioctl_resize(file, argp);
5418 case BTRFS_IOC_ADD_DEV:
5419 return btrfs_ioctl_add_dev(root, argp);
5420 case BTRFS_IOC_RM_DEV:
5421 return btrfs_ioctl_rm_dev(file, argp);
5422 case BTRFS_IOC_FS_INFO:
5423 return btrfs_ioctl_fs_info(root, argp);
5424 case BTRFS_IOC_DEV_INFO:
5425 return btrfs_ioctl_dev_info(root, argp);
5426 case BTRFS_IOC_BALANCE:
5427 return btrfs_ioctl_balance(file, NULL);
5428 case BTRFS_IOC_CLONE:
5429 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
5430 case BTRFS_IOC_CLONE_RANGE:
5431 return btrfs_ioctl_clone_range(file, argp);
5432 case BTRFS_IOC_TRANS_START:
5433 return btrfs_ioctl_trans_start(file);
5434 case BTRFS_IOC_TRANS_END:
5435 return btrfs_ioctl_trans_end(file);
5436 case BTRFS_IOC_TREE_SEARCH:
5437 return btrfs_ioctl_tree_search(file, argp);
5438 case BTRFS_IOC_TREE_SEARCH_V2:
5439 return btrfs_ioctl_tree_search_v2(file, argp);
5440 case BTRFS_IOC_INO_LOOKUP:
5441 return btrfs_ioctl_ino_lookup(file, argp);
5442 case BTRFS_IOC_INO_PATHS:
5443 return btrfs_ioctl_ino_to_path(root, argp);
5444 case BTRFS_IOC_LOGICAL_INO:
5445 return btrfs_ioctl_logical_to_ino(root, argp);
5446 case BTRFS_IOC_SPACE_INFO:
5447 return btrfs_ioctl_space_info(root, argp);
5448 case BTRFS_IOC_SYNC: {
5449 int ret;
5451 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
5452 if (ret)
5453 return ret;
5454 ret = btrfs_sync_fs(file_inode(file)->i_sb, 1);
5456 * The transaction thread may want to do more work,
5457 * namely it pokes the cleaner ktread that will start
5458 * processing uncleaned subvols.
5460 wake_up_process(root->fs_info->transaction_kthread);
5461 return ret;
5463 case BTRFS_IOC_START_SYNC:
5464 return btrfs_ioctl_start_sync(root, argp);
5465 case BTRFS_IOC_WAIT_SYNC:
5466 return btrfs_ioctl_wait_sync(root, argp);
5467 case BTRFS_IOC_SCRUB:
5468 return btrfs_ioctl_scrub(file, argp);
5469 case BTRFS_IOC_SCRUB_CANCEL:
5470 return btrfs_ioctl_scrub_cancel(root, argp);
5471 case BTRFS_IOC_SCRUB_PROGRESS:
5472 return btrfs_ioctl_scrub_progress(root, argp);
5473 case BTRFS_IOC_BALANCE_V2:
5474 return btrfs_ioctl_balance(file, argp);
5475 case BTRFS_IOC_BALANCE_CTL:
5476 return btrfs_ioctl_balance_ctl(root, arg);
5477 case BTRFS_IOC_BALANCE_PROGRESS:
5478 return btrfs_ioctl_balance_progress(root, argp);
5479 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5480 return btrfs_ioctl_set_received_subvol(file, argp);
5481 #ifdef CONFIG_64BIT
5482 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5483 return btrfs_ioctl_set_received_subvol_32(file, argp);
5484 #endif
5485 case BTRFS_IOC_SEND:
5486 return btrfs_ioctl_send(file, argp);
5487 case BTRFS_IOC_GET_DEV_STATS:
5488 return btrfs_ioctl_get_dev_stats(root, argp);
5489 case BTRFS_IOC_QUOTA_CTL:
5490 return btrfs_ioctl_quota_ctl(file, argp);
5491 case BTRFS_IOC_QGROUP_ASSIGN:
5492 return btrfs_ioctl_qgroup_assign(file, argp);
5493 case BTRFS_IOC_QGROUP_CREATE:
5494 return btrfs_ioctl_qgroup_create(file, argp);
5495 case BTRFS_IOC_QGROUP_LIMIT:
5496 return btrfs_ioctl_qgroup_limit(file, argp);
5497 case BTRFS_IOC_QUOTA_RESCAN:
5498 return btrfs_ioctl_quota_rescan(file, argp);
5499 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5500 return btrfs_ioctl_quota_rescan_status(file, argp);
5501 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5502 return btrfs_ioctl_quota_rescan_wait(file, argp);
5503 case BTRFS_IOC_DEV_REPLACE:
5504 return btrfs_ioctl_dev_replace(root, argp);
5505 case BTRFS_IOC_GET_FSLABEL:
5506 return btrfs_ioctl_get_fslabel(file, argp);
5507 case BTRFS_IOC_SET_FSLABEL:
5508 return btrfs_ioctl_set_fslabel(file, argp);
5509 case BTRFS_IOC_FILE_EXTENT_SAME:
5510 return btrfs_ioctl_file_extent_same(file, argp);
5511 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5512 return btrfs_ioctl_get_supported_features(file, argp);
5513 case BTRFS_IOC_GET_FEATURES:
5514 return btrfs_ioctl_get_features(file, argp);
5515 case BTRFS_IOC_SET_FEATURES:
5516 return btrfs_ioctl_set_features(file, argp);
5519 return -ENOTTY;