btrfs: Make btrfs_record_snapshot_destroy take btrfs_inode
[linux-2.6/btrfs-unstable.git] / fs / btrfs / ioctl.c
blob529cc273e817e6b41d32ce907d06127285513d77
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/compat.h>
37 #include <linux/bit_spinlock.h>
38 #include <linux/security.h>
39 #include <linux/xattr.h>
40 #include <linux/vmalloc.h>
41 #include <linux/slab.h>
42 #include <linux/blkdev.h>
43 #include <linux/uuid.h>
44 #include <linux/btrfs.h>
45 #include <linux/uaccess.h>
46 #include "ctree.h"
47 #include "disk-io.h"
48 #include "transaction.h"
49 #include "btrfs_inode.h"
50 #include "print-tree.h"
51 #include "volumes.h"
52 #include "locking.h"
53 #include "inode-map.h"
54 #include "backref.h"
55 #include "rcu-string.h"
56 #include "send.h"
57 #include "dev-replace.h"
58 #include "props.h"
59 #include "sysfs.h"
60 #include "qgroup.h"
61 #include "tree-log.h"
62 #include "compression.h"
64 #ifdef CONFIG_64BIT
65 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
66 * structures are incorrect, as the timespec structure from userspace
67 * is 4 bytes too small. We define these alternatives here to teach
68 * the kernel about the 32-bit struct packing.
70 struct btrfs_ioctl_timespec_32 {
71 __u64 sec;
72 __u32 nsec;
73 } __attribute__ ((__packed__));
75 struct btrfs_ioctl_received_subvol_args_32 {
76 char uuid[BTRFS_UUID_SIZE]; /* in */
77 __u64 stransid; /* in */
78 __u64 rtransid; /* out */
79 struct btrfs_ioctl_timespec_32 stime; /* in */
80 struct btrfs_ioctl_timespec_32 rtime; /* out */
81 __u64 flags; /* in */
82 __u64 reserved[16]; /* in */
83 } __attribute__ ((__packed__));
85 #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
86 struct btrfs_ioctl_received_subvol_args_32)
87 #endif
90 static int btrfs_clone(struct inode *src, struct inode *inode,
91 u64 off, u64 olen, u64 olen_aligned, u64 destoff,
92 int no_time_update);
94 /* Mask out flags that are inappropriate for the given type of inode. */
95 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
97 if (S_ISDIR(mode))
98 return flags;
99 else if (S_ISREG(mode))
100 return flags & ~FS_DIRSYNC_FL;
101 else
102 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
106 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
108 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
110 unsigned int iflags = 0;
112 if (flags & BTRFS_INODE_SYNC)
113 iflags |= FS_SYNC_FL;
114 if (flags & BTRFS_INODE_IMMUTABLE)
115 iflags |= FS_IMMUTABLE_FL;
116 if (flags & BTRFS_INODE_APPEND)
117 iflags |= FS_APPEND_FL;
118 if (flags & BTRFS_INODE_NODUMP)
119 iflags |= FS_NODUMP_FL;
120 if (flags & BTRFS_INODE_NOATIME)
121 iflags |= FS_NOATIME_FL;
122 if (flags & BTRFS_INODE_DIRSYNC)
123 iflags |= FS_DIRSYNC_FL;
124 if (flags & BTRFS_INODE_NODATACOW)
125 iflags |= FS_NOCOW_FL;
127 if (flags & BTRFS_INODE_NOCOMPRESS)
128 iflags |= FS_NOCOMP_FL;
129 else if (flags & BTRFS_INODE_COMPRESS)
130 iflags |= FS_COMPR_FL;
132 return iflags;
136 * Update inode->i_flags based on the btrfs internal flags.
138 void btrfs_update_iflags(struct inode *inode)
140 struct btrfs_inode *ip = BTRFS_I(inode);
141 unsigned int new_fl = 0;
143 if (ip->flags & BTRFS_INODE_SYNC)
144 new_fl |= S_SYNC;
145 if (ip->flags & BTRFS_INODE_IMMUTABLE)
146 new_fl |= S_IMMUTABLE;
147 if (ip->flags & BTRFS_INODE_APPEND)
148 new_fl |= S_APPEND;
149 if (ip->flags & BTRFS_INODE_NOATIME)
150 new_fl |= S_NOATIME;
151 if (ip->flags & BTRFS_INODE_DIRSYNC)
152 new_fl |= S_DIRSYNC;
154 set_mask_bits(&inode->i_flags,
155 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
156 new_fl);
160 * Inherit flags from the parent inode.
162 * Currently only the compression flags and the cow flags are inherited.
164 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
166 unsigned int flags;
168 if (!dir)
169 return;
171 flags = BTRFS_I(dir)->flags;
173 if (flags & BTRFS_INODE_NOCOMPRESS) {
174 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
175 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
176 } else if (flags & BTRFS_INODE_COMPRESS) {
177 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
178 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
181 if (flags & BTRFS_INODE_NODATACOW) {
182 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
183 if (S_ISREG(inode->i_mode))
184 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
187 btrfs_update_iflags(inode);
190 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
192 struct btrfs_inode *ip = BTRFS_I(file_inode(file));
193 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
195 if (copy_to_user(arg, &flags, sizeof(flags)))
196 return -EFAULT;
197 return 0;
200 static int check_flags(unsigned int flags)
202 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
203 FS_NOATIME_FL | FS_NODUMP_FL | \
204 FS_SYNC_FL | FS_DIRSYNC_FL | \
205 FS_NOCOMP_FL | FS_COMPR_FL |
206 FS_NOCOW_FL))
207 return -EOPNOTSUPP;
209 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
210 return -EINVAL;
212 return 0;
215 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
217 struct inode *inode = file_inode(file);
218 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
219 struct btrfs_inode *ip = BTRFS_I(inode);
220 struct btrfs_root *root = ip->root;
221 struct btrfs_trans_handle *trans;
222 unsigned int flags, oldflags;
223 int ret;
224 u64 ip_oldflags;
225 unsigned int i_oldflags;
226 umode_t mode;
228 if (!inode_owner_or_capable(inode))
229 return -EPERM;
231 if (btrfs_root_readonly(root))
232 return -EROFS;
234 if (copy_from_user(&flags, arg, sizeof(flags)))
235 return -EFAULT;
237 ret = check_flags(flags);
238 if (ret)
239 return ret;
241 ret = mnt_want_write_file(file);
242 if (ret)
243 return ret;
245 inode_lock(inode);
247 ip_oldflags = ip->flags;
248 i_oldflags = inode->i_flags;
249 mode = inode->i_mode;
251 flags = btrfs_mask_flags(inode->i_mode, flags);
252 oldflags = btrfs_flags_to_ioctl(ip->flags);
253 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
254 if (!capable(CAP_LINUX_IMMUTABLE)) {
255 ret = -EPERM;
256 goto out_unlock;
260 if (flags & FS_SYNC_FL)
261 ip->flags |= BTRFS_INODE_SYNC;
262 else
263 ip->flags &= ~BTRFS_INODE_SYNC;
264 if (flags & FS_IMMUTABLE_FL)
265 ip->flags |= BTRFS_INODE_IMMUTABLE;
266 else
267 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
268 if (flags & FS_APPEND_FL)
269 ip->flags |= BTRFS_INODE_APPEND;
270 else
271 ip->flags &= ~BTRFS_INODE_APPEND;
272 if (flags & FS_NODUMP_FL)
273 ip->flags |= BTRFS_INODE_NODUMP;
274 else
275 ip->flags &= ~BTRFS_INODE_NODUMP;
276 if (flags & FS_NOATIME_FL)
277 ip->flags |= BTRFS_INODE_NOATIME;
278 else
279 ip->flags &= ~BTRFS_INODE_NOATIME;
280 if (flags & FS_DIRSYNC_FL)
281 ip->flags |= BTRFS_INODE_DIRSYNC;
282 else
283 ip->flags &= ~BTRFS_INODE_DIRSYNC;
284 if (flags & FS_NOCOW_FL) {
285 if (S_ISREG(mode)) {
287 * It's safe to turn csums off here, no extents exist.
288 * Otherwise we want the flag to reflect the real COW
289 * status of the file and will not set it.
291 if (inode->i_size == 0)
292 ip->flags |= BTRFS_INODE_NODATACOW
293 | BTRFS_INODE_NODATASUM;
294 } else {
295 ip->flags |= BTRFS_INODE_NODATACOW;
297 } else {
299 * Revert back under same assumptions as above
301 if (S_ISREG(mode)) {
302 if (inode->i_size == 0)
303 ip->flags &= ~(BTRFS_INODE_NODATACOW
304 | BTRFS_INODE_NODATASUM);
305 } else {
306 ip->flags &= ~BTRFS_INODE_NODATACOW;
311 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
312 * flag may be changed automatically if compression code won't make
313 * things smaller.
315 if (flags & FS_NOCOMP_FL) {
316 ip->flags &= ~BTRFS_INODE_COMPRESS;
317 ip->flags |= BTRFS_INODE_NOCOMPRESS;
319 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
320 if (ret && ret != -ENODATA)
321 goto out_drop;
322 } else if (flags & FS_COMPR_FL) {
323 const char *comp;
325 ip->flags |= BTRFS_INODE_COMPRESS;
326 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
328 if (fs_info->compress_type == BTRFS_COMPRESS_LZO)
329 comp = "lzo";
330 else
331 comp = "zlib";
332 ret = btrfs_set_prop(inode, "btrfs.compression",
333 comp, strlen(comp), 0);
334 if (ret)
335 goto out_drop;
337 } else {
338 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
339 if (ret && ret != -ENODATA)
340 goto out_drop;
341 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
344 trans = btrfs_start_transaction(root, 1);
345 if (IS_ERR(trans)) {
346 ret = PTR_ERR(trans);
347 goto out_drop;
350 btrfs_update_iflags(inode);
351 inode_inc_iversion(inode);
352 inode->i_ctime = current_time(inode);
353 ret = btrfs_update_inode(trans, root, inode);
355 btrfs_end_transaction(trans);
356 out_drop:
357 if (ret) {
358 ip->flags = ip_oldflags;
359 inode->i_flags = i_oldflags;
362 out_unlock:
363 inode_unlock(inode);
364 mnt_drop_write_file(file);
365 return ret;
368 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
370 struct inode *inode = file_inode(file);
372 return put_user(inode->i_generation, arg);
375 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
377 struct inode *inode = file_inode(file);
378 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
379 struct btrfs_device *device;
380 struct request_queue *q;
381 struct fstrim_range range;
382 u64 minlen = ULLONG_MAX;
383 u64 num_devices = 0;
384 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
385 int ret;
387 if (!capable(CAP_SYS_ADMIN))
388 return -EPERM;
390 rcu_read_lock();
391 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
392 dev_list) {
393 if (!device->bdev)
394 continue;
395 q = bdev_get_queue(device->bdev);
396 if (blk_queue_discard(q)) {
397 num_devices++;
398 minlen = min_t(u64, q->limits.discard_granularity,
399 minlen);
402 rcu_read_unlock();
404 if (!num_devices)
405 return -EOPNOTSUPP;
406 if (copy_from_user(&range, arg, sizeof(range)))
407 return -EFAULT;
408 if (range.start > total_bytes ||
409 range.len < fs_info->sb->s_blocksize)
410 return -EINVAL;
412 range.len = min(range.len, total_bytes - range.start);
413 range.minlen = max(range.minlen, minlen);
414 ret = btrfs_trim_fs(fs_info, &range);
415 if (ret < 0)
416 return ret;
418 if (copy_to_user(arg, &range, sizeof(range)))
419 return -EFAULT;
421 return 0;
424 int btrfs_is_empty_uuid(u8 *uuid)
426 int i;
428 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
429 if (uuid[i])
430 return 0;
432 return 1;
435 static noinline int create_subvol(struct inode *dir,
436 struct dentry *dentry,
437 char *name, int namelen,
438 u64 *async_transid,
439 struct btrfs_qgroup_inherit *inherit)
441 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
442 struct btrfs_trans_handle *trans;
443 struct btrfs_key key;
444 struct btrfs_root_item *root_item;
445 struct btrfs_inode_item *inode_item;
446 struct extent_buffer *leaf;
447 struct btrfs_root *root = BTRFS_I(dir)->root;
448 struct btrfs_root *new_root;
449 struct btrfs_block_rsv block_rsv;
450 struct timespec cur_time = current_time(dir);
451 struct inode *inode;
452 int ret;
453 int err;
454 u64 objectid;
455 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
456 u64 index = 0;
457 u64 qgroup_reserved;
458 uuid_le new_uuid;
460 root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
461 if (!root_item)
462 return -ENOMEM;
464 ret = btrfs_find_free_objectid(fs_info->tree_root, &objectid);
465 if (ret)
466 goto fail_free;
469 * Don't create subvolume whose level is not zero. Or qgroup will be
470 * screwed up since it assumes subvolume qgroup's level to be 0.
472 if (btrfs_qgroup_level(objectid)) {
473 ret = -ENOSPC;
474 goto fail_free;
477 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
479 * The same as the snapshot creation, please see the comment
480 * of create_snapshot().
482 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
483 8, &qgroup_reserved, false);
484 if (ret)
485 goto fail_free;
487 trans = btrfs_start_transaction(root, 0);
488 if (IS_ERR(trans)) {
489 ret = PTR_ERR(trans);
490 btrfs_subvolume_release_metadata(fs_info, &block_rsv,
491 qgroup_reserved);
492 goto fail_free;
494 trans->block_rsv = &block_rsv;
495 trans->bytes_reserved = block_rsv.size;
497 ret = btrfs_qgroup_inherit(trans, fs_info, 0, objectid, inherit);
498 if (ret)
499 goto fail;
501 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
502 if (IS_ERR(leaf)) {
503 ret = PTR_ERR(leaf);
504 goto fail;
507 memzero_extent_buffer(leaf, 0, sizeof(struct btrfs_header));
508 btrfs_set_header_bytenr(leaf, leaf->start);
509 btrfs_set_header_generation(leaf, trans->transid);
510 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
511 btrfs_set_header_owner(leaf, objectid);
513 write_extent_buffer_fsid(leaf, fs_info->fsid);
514 write_extent_buffer_chunk_tree_uuid(leaf, fs_info->chunk_tree_uuid);
515 btrfs_mark_buffer_dirty(leaf);
517 inode_item = &root_item->inode;
518 btrfs_set_stack_inode_generation(inode_item, 1);
519 btrfs_set_stack_inode_size(inode_item, 3);
520 btrfs_set_stack_inode_nlink(inode_item, 1);
521 btrfs_set_stack_inode_nbytes(inode_item,
522 fs_info->nodesize);
523 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
525 btrfs_set_root_flags(root_item, 0);
526 btrfs_set_root_limit(root_item, 0);
527 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
529 btrfs_set_root_bytenr(root_item, leaf->start);
530 btrfs_set_root_generation(root_item, trans->transid);
531 btrfs_set_root_level(root_item, 0);
532 btrfs_set_root_refs(root_item, 1);
533 btrfs_set_root_used(root_item, leaf->len);
534 btrfs_set_root_last_snapshot(root_item, 0);
536 btrfs_set_root_generation_v2(root_item,
537 btrfs_root_generation(root_item));
538 uuid_le_gen(&new_uuid);
539 memcpy(root_item->uuid, new_uuid.b, BTRFS_UUID_SIZE);
540 btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);
541 btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);
542 root_item->ctime = root_item->otime;
543 btrfs_set_root_ctransid(root_item, trans->transid);
544 btrfs_set_root_otransid(root_item, trans->transid);
546 btrfs_tree_unlock(leaf);
547 free_extent_buffer(leaf);
548 leaf = NULL;
550 btrfs_set_root_dirid(root_item, new_dirid);
552 key.objectid = objectid;
553 key.offset = 0;
554 key.type = BTRFS_ROOT_ITEM_KEY;
555 ret = btrfs_insert_root(trans, fs_info->tree_root, &key,
556 root_item);
557 if (ret)
558 goto fail;
560 key.offset = (u64)-1;
561 new_root = btrfs_read_fs_root_no_name(fs_info, &key);
562 if (IS_ERR(new_root)) {
563 ret = PTR_ERR(new_root);
564 btrfs_abort_transaction(trans, ret);
565 goto fail;
568 btrfs_record_root_in_trans(trans, new_root);
570 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
571 if (ret) {
572 /* We potentially lose an unused inode item here */
573 btrfs_abort_transaction(trans, ret);
574 goto fail;
577 mutex_lock(&new_root->objectid_mutex);
578 new_root->highest_objectid = new_dirid;
579 mutex_unlock(&new_root->objectid_mutex);
582 * insert the directory item
584 ret = btrfs_set_inode_index(dir, &index);
585 if (ret) {
586 btrfs_abort_transaction(trans, ret);
587 goto fail;
590 ret = btrfs_insert_dir_item(trans, root,
591 name, namelen, dir, &key,
592 BTRFS_FT_DIR, index);
593 if (ret) {
594 btrfs_abort_transaction(trans, ret);
595 goto fail;
598 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
599 ret = btrfs_update_inode(trans, root, dir);
600 BUG_ON(ret);
602 ret = btrfs_add_root_ref(trans, fs_info,
603 objectid, root->root_key.objectid,
604 btrfs_ino(BTRFS_I(dir)), index, name, namelen);
605 BUG_ON(ret);
607 ret = btrfs_uuid_tree_add(trans, fs_info, root_item->uuid,
608 BTRFS_UUID_KEY_SUBVOL, objectid);
609 if (ret)
610 btrfs_abort_transaction(trans, ret);
612 fail:
613 kfree(root_item);
614 trans->block_rsv = NULL;
615 trans->bytes_reserved = 0;
616 btrfs_subvolume_release_metadata(fs_info, &block_rsv, qgroup_reserved);
618 if (async_transid) {
619 *async_transid = trans->transid;
620 err = btrfs_commit_transaction_async(trans, 1);
621 if (err)
622 err = btrfs_commit_transaction(trans);
623 } else {
624 err = btrfs_commit_transaction(trans);
626 if (err && !ret)
627 ret = err;
629 if (!ret) {
630 inode = btrfs_lookup_dentry(dir, dentry);
631 if (IS_ERR(inode))
632 return PTR_ERR(inode);
633 d_instantiate(dentry, inode);
635 return ret;
637 fail_free:
638 kfree(root_item);
639 return ret;
642 static void btrfs_wait_for_no_snapshoting_writes(struct btrfs_root *root)
644 s64 writers;
645 DEFINE_WAIT(wait);
647 do {
648 prepare_to_wait(&root->subv_writers->wait, &wait,
649 TASK_UNINTERRUPTIBLE);
651 writers = percpu_counter_sum(&root->subv_writers->counter);
652 if (writers)
653 schedule();
655 finish_wait(&root->subv_writers->wait, &wait);
656 } while (writers);
659 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
660 struct dentry *dentry, char *name, int namelen,
661 u64 *async_transid, bool readonly,
662 struct btrfs_qgroup_inherit *inherit)
664 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
665 struct inode *inode;
666 struct btrfs_pending_snapshot *pending_snapshot;
667 struct btrfs_trans_handle *trans;
668 int ret;
670 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
671 return -EINVAL;
673 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
674 if (!pending_snapshot)
675 return -ENOMEM;
677 pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
678 GFP_NOFS);
679 pending_snapshot->path = btrfs_alloc_path();
680 if (!pending_snapshot->root_item || !pending_snapshot->path) {
681 ret = -ENOMEM;
682 goto free_pending;
685 atomic_inc(&root->will_be_snapshoted);
686 smp_mb__after_atomic();
687 btrfs_wait_for_no_snapshoting_writes(root);
689 ret = btrfs_start_delalloc_inodes(root, 0);
690 if (ret)
691 goto dec_and_free;
693 btrfs_wait_ordered_extents(root, -1, 0, (u64)-1);
695 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
696 BTRFS_BLOCK_RSV_TEMP);
698 * 1 - parent dir inode
699 * 2 - dir entries
700 * 1 - root item
701 * 2 - root ref/backref
702 * 1 - root of snapshot
703 * 1 - UUID item
705 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
706 &pending_snapshot->block_rsv, 8,
707 &pending_snapshot->qgroup_reserved,
708 false);
709 if (ret)
710 goto dec_and_free;
712 pending_snapshot->dentry = dentry;
713 pending_snapshot->root = root;
714 pending_snapshot->readonly = readonly;
715 pending_snapshot->dir = dir;
716 pending_snapshot->inherit = inherit;
718 trans = btrfs_start_transaction(root, 0);
719 if (IS_ERR(trans)) {
720 ret = PTR_ERR(trans);
721 goto fail;
724 spin_lock(&fs_info->trans_lock);
725 list_add(&pending_snapshot->list,
726 &trans->transaction->pending_snapshots);
727 spin_unlock(&fs_info->trans_lock);
728 if (async_transid) {
729 *async_transid = trans->transid;
730 ret = btrfs_commit_transaction_async(trans, 1);
731 if (ret)
732 ret = btrfs_commit_transaction(trans);
733 } else {
734 ret = btrfs_commit_transaction(trans);
736 if (ret)
737 goto fail;
739 ret = pending_snapshot->error;
740 if (ret)
741 goto fail;
743 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
744 if (ret)
745 goto fail;
747 inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
748 if (IS_ERR(inode)) {
749 ret = PTR_ERR(inode);
750 goto fail;
753 d_instantiate(dentry, inode);
754 ret = 0;
755 fail:
756 btrfs_subvolume_release_metadata(fs_info,
757 &pending_snapshot->block_rsv,
758 pending_snapshot->qgroup_reserved);
759 dec_and_free:
760 if (atomic_dec_and_test(&root->will_be_snapshoted))
761 wake_up_atomic_t(&root->will_be_snapshoted);
762 free_pending:
763 kfree(pending_snapshot->root_item);
764 btrfs_free_path(pending_snapshot->path);
765 kfree(pending_snapshot);
767 return ret;
770 /* copy of may_delete in fs/namei.c()
771 * Check whether we can remove a link victim from directory dir, check
772 * whether the type of victim is right.
773 * 1. We can't do it if dir is read-only (done in permission())
774 * 2. We should have write and exec permissions on dir
775 * 3. We can't remove anything from append-only dir
776 * 4. We can't do anything with immutable dir (done in permission())
777 * 5. If the sticky bit on dir is set we should either
778 * a. be owner of dir, or
779 * b. be owner of victim, or
780 * c. have CAP_FOWNER capability
781 * 6. If the victim is append-only or immutable we can't do anything with
782 * links pointing to it.
783 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
784 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
785 * 9. We can't remove a root or mountpoint.
786 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
787 * nfs_async_unlink().
790 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
792 int error;
794 if (d_really_is_negative(victim))
795 return -ENOENT;
797 BUG_ON(d_inode(victim->d_parent) != dir);
798 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
800 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
801 if (error)
802 return error;
803 if (IS_APPEND(dir))
804 return -EPERM;
805 if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
806 IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
807 return -EPERM;
808 if (isdir) {
809 if (!d_is_dir(victim))
810 return -ENOTDIR;
811 if (IS_ROOT(victim))
812 return -EBUSY;
813 } else if (d_is_dir(victim))
814 return -EISDIR;
815 if (IS_DEADDIR(dir))
816 return -ENOENT;
817 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
818 return -EBUSY;
819 return 0;
822 /* copy of may_create in fs/namei.c() */
823 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
825 if (d_really_is_positive(child))
826 return -EEXIST;
827 if (IS_DEADDIR(dir))
828 return -ENOENT;
829 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
833 * Create a new subvolume below @parent. This is largely modeled after
834 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
835 * inside this filesystem so it's quite a bit simpler.
837 static noinline int btrfs_mksubvol(const struct path *parent,
838 char *name, int namelen,
839 struct btrfs_root *snap_src,
840 u64 *async_transid, bool readonly,
841 struct btrfs_qgroup_inherit *inherit)
843 struct inode *dir = d_inode(parent->dentry);
844 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
845 struct dentry *dentry;
846 int error;
848 error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
849 if (error == -EINTR)
850 return error;
852 dentry = lookup_one_len(name, parent->dentry, namelen);
853 error = PTR_ERR(dentry);
854 if (IS_ERR(dentry))
855 goto out_unlock;
857 error = btrfs_may_create(dir, dentry);
858 if (error)
859 goto out_dput;
862 * even if this name doesn't exist, we may get hash collisions.
863 * check for them now when we can safely fail
865 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
866 dir->i_ino, name,
867 namelen);
868 if (error)
869 goto out_dput;
871 down_read(&fs_info->subvol_sem);
873 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
874 goto out_up_read;
876 if (snap_src) {
877 error = create_snapshot(snap_src, dir, dentry, name, namelen,
878 async_transid, readonly, inherit);
879 } else {
880 error = create_subvol(dir, dentry, name, namelen,
881 async_transid, inherit);
883 if (!error)
884 fsnotify_mkdir(dir, dentry);
885 out_up_read:
886 up_read(&fs_info->subvol_sem);
887 out_dput:
888 dput(dentry);
889 out_unlock:
890 inode_unlock(dir);
891 return error;
895 * When we're defragging a range, we don't want to kick it off again
896 * if it is really just waiting for delalloc to send it down.
897 * If we find a nice big extent or delalloc range for the bytes in the
898 * file you want to defrag, we return 0 to let you know to skip this
899 * part of the file
901 static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
903 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
904 struct extent_map *em = NULL;
905 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
906 u64 end;
908 read_lock(&em_tree->lock);
909 em = lookup_extent_mapping(em_tree, offset, PAGE_SIZE);
910 read_unlock(&em_tree->lock);
912 if (em) {
913 end = extent_map_end(em);
914 free_extent_map(em);
915 if (end - offset > thresh)
916 return 0;
918 /* if we already have a nice delalloc here, just stop */
919 thresh /= 2;
920 end = count_range_bits(io_tree, &offset, offset + thresh,
921 thresh, EXTENT_DELALLOC, 1);
922 if (end >= thresh)
923 return 0;
924 return 1;
928 * helper function to walk through a file and find extents
929 * newer than a specific transid, and smaller than thresh.
931 * This is used by the defragging code to find new and small
932 * extents
934 static int find_new_extents(struct btrfs_root *root,
935 struct inode *inode, u64 newer_than,
936 u64 *off, u32 thresh)
938 struct btrfs_path *path;
939 struct btrfs_key min_key;
940 struct extent_buffer *leaf;
941 struct btrfs_file_extent_item *extent;
942 int type;
943 int ret;
944 u64 ino = btrfs_ino(BTRFS_I(inode));
946 path = btrfs_alloc_path();
947 if (!path)
948 return -ENOMEM;
950 min_key.objectid = ino;
951 min_key.type = BTRFS_EXTENT_DATA_KEY;
952 min_key.offset = *off;
954 while (1) {
955 ret = btrfs_search_forward(root, &min_key, path, newer_than);
956 if (ret != 0)
957 goto none;
958 process_slot:
959 if (min_key.objectid != ino)
960 goto none;
961 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
962 goto none;
964 leaf = path->nodes[0];
965 extent = btrfs_item_ptr(leaf, path->slots[0],
966 struct btrfs_file_extent_item);
968 type = btrfs_file_extent_type(leaf, extent);
969 if (type == BTRFS_FILE_EXTENT_REG &&
970 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
971 check_defrag_in_cache(inode, min_key.offset, thresh)) {
972 *off = min_key.offset;
973 btrfs_free_path(path);
974 return 0;
977 path->slots[0]++;
978 if (path->slots[0] < btrfs_header_nritems(leaf)) {
979 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
980 goto process_slot;
983 if (min_key.offset == (u64)-1)
984 goto none;
986 min_key.offset++;
987 btrfs_release_path(path);
989 none:
990 btrfs_free_path(path);
991 return -ENOENT;
994 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
996 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
997 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
998 struct extent_map *em;
999 u64 len = PAGE_SIZE;
1002 * hopefully we have this extent in the tree already, try without
1003 * the full extent lock
1005 read_lock(&em_tree->lock);
1006 em = lookup_extent_mapping(em_tree, start, len);
1007 read_unlock(&em_tree->lock);
1009 if (!em) {
1010 struct extent_state *cached = NULL;
1011 u64 end = start + len - 1;
1013 /* get the big lock and read metadata off disk */
1014 lock_extent_bits(io_tree, start, end, &cached);
1015 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
1016 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
1018 if (IS_ERR(em))
1019 return NULL;
1022 return em;
1025 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1027 struct extent_map *next;
1028 bool ret = true;
1030 /* this is the last extent */
1031 if (em->start + em->len >= i_size_read(inode))
1032 return false;
1034 next = defrag_lookup_extent(inode, em->start + em->len);
1035 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1036 ret = false;
1037 else if ((em->block_start + em->block_len == next->block_start) &&
1038 (em->block_len > SZ_128K && next->block_len > SZ_128K))
1039 ret = false;
1041 free_extent_map(next);
1042 return ret;
1045 static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1046 u64 *last_len, u64 *skip, u64 *defrag_end,
1047 int compress)
1049 struct extent_map *em;
1050 int ret = 1;
1051 bool next_mergeable = true;
1052 bool prev_mergeable = true;
1055 * make sure that once we start defragging an extent, we keep on
1056 * defragging it
1058 if (start < *defrag_end)
1059 return 1;
1061 *skip = 0;
1063 em = defrag_lookup_extent(inode, start);
1064 if (!em)
1065 return 0;
1067 /* this will cover holes, and inline extents */
1068 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1069 ret = 0;
1070 goto out;
1073 if (!*defrag_end)
1074 prev_mergeable = false;
1076 next_mergeable = defrag_check_next_extent(inode, em);
1078 * we hit a real extent, if it is big or the next extent is not a
1079 * real extent, don't bother defragging it
1081 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1082 (em->len >= thresh || (!next_mergeable && !prev_mergeable)))
1083 ret = 0;
1084 out:
1086 * last_len ends up being a counter of how many bytes we've defragged.
1087 * every time we choose not to defrag an extent, we reset *last_len
1088 * so that the next tiny extent will force a defrag.
1090 * The end result of this is that tiny extents before a single big
1091 * extent will force at least part of that big extent to be defragged.
1093 if (ret) {
1094 *defrag_end = extent_map_end(em);
1095 } else {
1096 *last_len = 0;
1097 *skip = extent_map_end(em);
1098 *defrag_end = 0;
1101 free_extent_map(em);
1102 return ret;
1106 * it doesn't do much good to defrag one or two pages
1107 * at a time. This pulls in a nice chunk of pages
1108 * to COW and defrag.
1110 * It also makes sure the delalloc code has enough
1111 * dirty data to avoid making new small extents as part
1112 * of the defrag
1114 * It's a good idea to start RA on this range
1115 * before calling this.
1117 static int cluster_pages_for_defrag(struct inode *inode,
1118 struct page **pages,
1119 unsigned long start_index,
1120 unsigned long num_pages)
1122 unsigned long file_end;
1123 u64 isize = i_size_read(inode);
1124 u64 page_start;
1125 u64 page_end;
1126 u64 page_cnt;
1127 int ret;
1128 int i;
1129 int i_done;
1130 struct btrfs_ordered_extent *ordered;
1131 struct extent_state *cached_state = NULL;
1132 struct extent_io_tree *tree;
1133 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1135 file_end = (isize - 1) >> PAGE_SHIFT;
1136 if (!isize || start_index > file_end)
1137 return 0;
1139 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1141 ret = btrfs_delalloc_reserve_space(inode,
1142 start_index << PAGE_SHIFT,
1143 page_cnt << PAGE_SHIFT);
1144 if (ret)
1145 return ret;
1146 i_done = 0;
1147 tree = &BTRFS_I(inode)->io_tree;
1149 /* step one, lock all the pages */
1150 for (i = 0; i < page_cnt; i++) {
1151 struct page *page;
1152 again:
1153 page = find_or_create_page(inode->i_mapping,
1154 start_index + i, mask);
1155 if (!page)
1156 break;
1158 page_start = page_offset(page);
1159 page_end = page_start + PAGE_SIZE - 1;
1160 while (1) {
1161 lock_extent_bits(tree, page_start, page_end,
1162 &cached_state);
1163 ordered = btrfs_lookup_ordered_extent(inode,
1164 page_start);
1165 unlock_extent_cached(tree, page_start, page_end,
1166 &cached_state, GFP_NOFS);
1167 if (!ordered)
1168 break;
1170 unlock_page(page);
1171 btrfs_start_ordered_extent(inode, ordered, 1);
1172 btrfs_put_ordered_extent(ordered);
1173 lock_page(page);
1175 * we unlocked the page above, so we need check if
1176 * it was released or not.
1178 if (page->mapping != inode->i_mapping) {
1179 unlock_page(page);
1180 put_page(page);
1181 goto again;
1185 if (!PageUptodate(page)) {
1186 btrfs_readpage(NULL, page);
1187 lock_page(page);
1188 if (!PageUptodate(page)) {
1189 unlock_page(page);
1190 put_page(page);
1191 ret = -EIO;
1192 break;
1196 if (page->mapping != inode->i_mapping) {
1197 unlock_page(page);
1198 put_page(page);
1199 goto again;
1202 pages[i] = page;
1203 i_done++;
1205 if (!i_done || ret)
1206 goto out;
1208 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1209 goto out;
1212 * so now we have a nice long stream of locked
1213 * and up to date pages, lets wait on them
1215 for (i = 0; i < i_done; i++)
1216 wait_on_page_writeback(pages[i]);
1218 page_start = page_offset(pages[0]);
1219 page_end = page_offset(pages[i_done - 1]) + PAGE_SIZE;
1221 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1222 page_start, page_end - 1, &cached_state);
1223 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1224 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1225 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1226 &cached_state, GFP_NOFS);
1228 if (i_done != page_cnt) {
1229 spin_lock(&BTRFS_I(inode)->lock);
1230 BTRFS_I(inode)->outstanding_extents++;
1231 spin_unlock(&BTRFS_I(inode)->lock);
1232 btrfs_delalloc_release_space(inode,
1233 start_index << PAGE_SHIFT,
1234 (page_cnt - i_done) << PAGE_SHIFT);
1238 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1239 &cached_state);
1241 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1242 page_start, page_end - 1, &cached_state,
1243 GFP_NOFS);
1245 for (i = 0; i < i_done; i++) {
1246 clear_page_dirty_for_io(pages[i]);
1247 ClearPageChecked(pages[i]);
1248 set_page_extent_mapped(pages[i]);
1249 set_page_dirty(pages[i]);
1250 unlock_page(pages[i]);
1251 put_page(pages[i]);
1253 return i_done;
1254 out:
1255 for (i = 0; i < i_done; i++) {
1256 unlock_page(pages[i]);
1257 put_page(pages[i]);
1259 btrfs_delalloc_release_space(inode,
1260 start_index << PAGE_SHIFT,
1261 page_cnt << PAGE_SHIFT);
1262 return ret;
1266 int btrfs_defrag_file(struct inode *inode, struct file *file,
1267 struct btrfs_ioctl_defrag_range_args *range,
1268 u64 newer_than, unsigned long max_to_defrag)
1270 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1271 struct btrfs_root *root = BTRFS_I(inode)->root;
1272 struct file_ra_state *ra = NULL;
1273 unsigned long last_index;
1274 u64 isize = i_size_read(inode);
1275 u64 last_len = 0;
1276 u64 skip = 0;
1277 u64 defrag_end = 0;
1278 u64 newer_off = range->start;
1279 unsigned long i;
1280 unsigned long ra_index = 0;
1281 int ret;
1282 int defrag_count = 0;
1283 int compress_type = BTRFS_COMPRESS_ZLIB;
1284 u32 extent_thresh = range->extent_thresh;
1285 unsigned long max_cluster = SZ_256K >> PAGE_SHIFT;
1286 unsigned long cluster = max_cluster;
1287 u64 new_align = ~((u64)SZ_128K - 1);
1288 struct page **pages = NULL;
1290 if (isize == 0)
1291 return 0;
1293 if (range->start >= isize)
1294 return -EINVAL;
1296 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1297 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1298 return -EINVAL;
1299 if (range->compress_type)
1300 compress_type = range->compress_type;
1303 if (extent_thresh == 0)
1304 extent_thresh = SZ_256K;
1307 * if we were not given a file, allocate a readahead
1308 * context
1310 if (!file) {
1311 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1312 if (!ra)
1313 return -ENOMEM;
1314 file_ra_state_init(ra, inode->i_mapping);
1315 } else {
1316 ra = &file->f_ra;
1319 pages = kmalloc_array(max_cluster, sizeof(struct page *),
1320 GFP_NOFS);
1321 if (!pages) {
1322 ret = -ENOMEM;
1323 goto out_ra;
1326 /* find the last page to defrag */
1327 if (range->start + range->len > range->start) {
1328 last_index = min_t(u64, isize - 1,
1329 range->start + range->len - 1) >> PAGE_SHIFT;
1330 } else {
1331 last_index = (isize - 1) >> PAGE_SHIFT;
1334 if (newer_than) {
1335 ret = find_new_extents(root, inode, newer_than,
1336 &newer_off, SZ_64K);
1337 if (!ret) {
1338 range->start = newer_off;
1340 * we always align our defrag to help keep
1341 * the extents in the file evenly spaced
1343 i = (newer_off & new_align) >> PAGE_SHIFT;
1344 } else
1345 goto out_ra;
1346 } else {
1347 i = range->start >> PAGE_SHIFT;
1349 if (!max_to_defrag)
1350 max_to_defrag = last_index - i + 1;
1353 * make writeback starts from i, so the defrag range can be
1354 * written sequentially.
1356 if (i < inode->i_mapping->writeback_index)
1357 inode->i_mapping->writeback_index = i;
1359 while (i <= last_index && defrag_count < max_to_defrag &&
1360 (i < DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE))) {
1362 * make sure we stop running if someone unmounts
1363 * the FS
1365 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1366 break;
1368 if (btrfs_defrag_cancelled(fs_info)) {
1369 btrfs_debug(fs_info, "defrag_file cancelled");
1370 ret = -EAGAIN;
1371 break;
1374 if (!should_defrag_range(inode, (u64)i << PAGE_SHIFT,
1375 extent_thresh, &last_len, &skip,
1376 &defrag_end, range->flags &
1377 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1378 unsigned long next;
1380 * the should_defrag function tells us how much to skip
1381 * bump our counter by the suggested amount
1383 next = DIV_ROUND_UP(skip, PAGE_SIZE);
1384 i = max(i + 1, next);
1385 continue;
1388 if (!newer_than) {
1389 cluster = (PAGE_ALIGN(defrag_end) >>
1390 PAGE_SHIFT) - i;
1391 cluster = min(cluster, max_cluster);
1392 } else {
1393 cluster = max_cluster;
1396 if (i + cluster > ra_index) {
1397 ra_index = max(i, ra_index);
1398 btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1399 cluster);
1400 ra_index += cluster;
1403 inode_lock(inode);
1404 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1405 BTRFS_I(inode)->force_compress = compress_type;
1406 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1407 if (ret < 0) {
1408 inode_unlock(inode);
1409 goto out_ra;
1412 defrag_count += ret;
1413 balance_dirty_pages_ratelimited(inode->i_mapping);
1414 inode_unlock(inode);
1416 if (newer_than) {
1417 if (newer_off == (u64)-1)
1418 break;
1420 if (ret > 0)
1421 i += ret;
1423 newer_off = max(newer_off + 1,
1424 (u64)i << PAGE_SHIFT);
1426 ret = find_new_extents(root, inode, newer_than,
1427 &newer_off, SZ_64K);
1428 if (!ret) {
1429 range->start = newer_off;
1430 i = (newer_off & new_align) >> PAGE_SHIFT;
1431 } else {
1432 break;
1434 } else {
1435 if (ret > 0) {
1436 i += ret;
1437 last_len += ret << PAGE_SHIFT;
1438 } else {
1439 i++;
1440 last_len = 0;
1445 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1446 filemap_flush(inode->i_mapping);
1447 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1448 &BTRFS_I(inode)->runtime_flags))
1449 filemap_flush(inode->i_mapping);
1452 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1453 /* the filemap_flush will queue IO into the worker threads, but
1454 * we have to make sure the IO is actually started and that
1455 * ordered extents get created before we return
1457 atomic_inc(&fs_info->async_submit_draining);
1458 while (atomic_read(&fs_info->nr_async_submits) ||
1459 atomic_read(&fs_info->async_delalloc_pages)) {
1460 wait_event(fs_info->async_submit_wait,
1461 (atomic_read(&fs_info->nr_async_submits) == 0 &&
1462 atomic_read(&fs_info->async_delalloc_pages) == 0));
1464 atomic_dec(&fs_info->async_submit_draining);
1467 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1468 btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
1471 ret = defrag_count;
1473 out_ra:
1474 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1475 inode_lock(inode);
1476 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1477 inode_unlock(inode);
1479 if (!file)
1480 kfree(ra);
1481 kfree(pages);
1482 return ret;
1485 static noinline int btrfs_ioctl_resize(struct file *file,
1486 void __user *arg)
1488 struct inode *inode = file_inode(file);
1489 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1490 u64 new_size;
1491 u64 old_size;
1492 u64 devid = 1;
1493 struct btrfs_root *root = BTRFS_I(inode)->root;
1494 struct btrfs_ioctl_vol_args *vol_args;
1495 struct btrfs_trans_handle *trans;
1496 struct btrfs_device *device = NULL;
1497 char *sizestr;
1498 char *retptr;
1499 char *devstr = NULL;
1500 int ret = 0;
1501 int mod = 0;
1503 if (!capable(CAP_SYS_ADMIN))
1504 return -EPERM;
1506 ret = mnt_want_write_file(file);
1507 if (ret)
1508 return ret;
1510 if (atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
1511 mnt_drop_write_file(file);
1512 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1515 mutex_lock(&fs_info->volume_mutex);
1516 vol_args = memdup_user(arg, sizeof(*vol_args));
1517 if (IS_ERR(vol_args)) {
1518 ret = PTR_ERR(vol_args);
1519 goto out;
1522 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1524 sizestr = vol_args->name;
1525 devstr = strchr(sizestr, ':');
1526 if (devstr) {
1527 sizestr = devstr + 1;
1528 *devstr = '\0';
1529 devstr = vol_args->name;
1530 ret = kstrtoull(devstr, 10, &devid);
1531 if (ret)
1532 goto out_free;
1533 if (!devid) {
1534 ret = -EINVAL;
1535 goto out_free;
1537 btrfs_info(fs_info, "resizing devid %llu", devid);
1540 device = btrfs_find_device(fs_info, devid, NULL, NULL);
1541 if (!device) {
1542 btrfs_info(fs_info, "resizer unable to find device %llu",
1543 devid);
1544 ret = -ENODEV;
1545 goto out_free;
1548 if (!device->writeable) {
1549 btrfs_info(fs_info,
1550 "resizer unable to apply on readonly device %llu",
1551 devid);
1552 ret = -EPERM;
1553 goto out_free;
1556 if (!strcmp(sizestr, "max"))
1557 new_size = device->bdev->bd_inode->i_size;
1558 else {
1559 if (sizestr[0] == '-') {
1560 mod = -1;
1561 sizestr++;
1562 } else if (sizestr[0] == '+') {
1563 mod = 1;
1564 sizestr++;
1566 new_size = memparse(sizestr, &retptr);
1567 if (*retptr != '\0' || new_size == 0) {
1568 ret = -EINVAL;
1569 goto out_free;
1573 if (device->is_tgtdev_for_dev_replace) {
1574 ret = -EPERM;
1575 goto out_free;
1578 old_size = btrfs_device_get_total_bytes(device);
1580 if (mod < 0) {
1581 if (new_size > old_size) {
1582 ret = -EINVAL;
1583 goto out_free;
1585 new_size = old_size - new_size;
1586 } else if (mod > 0) {
1587 if (new_size > ULLONG_MAX - old_size) {
1588 ret = -ERANGE;
1589 goto out_free;
1591 new_size = old_size + new_size;
1594 if (new_size < SZ_256M) {
1595 ret = -EINVAL;
1596 goto out_free;
1598 if (new_size > device->bdev->bd_inode->i_size) {
1599 ret = -EFBIG;
1600 goto out_free;
1603 new_size = div_u64(new_size, fs_info->sectorsize);
1604 new_size *= fs_info->sectorsize;
1606 btrfs_info_in_rcu(fs_info, "new size for %s is %llu",
1607 rcu_str_deref(device->name), new_size);
1609 if (new_size > old_size) {
1610 trans = btrfs_start_transaction(root, 0);
1611 if (IS_ERR(trans)) {
1612 ret = PTR_ERR(trans);
1613 goto out_free;
1615 ret = btrfs_grow_device(trans, device, new_size);
1616 btrfs_commit_transaction(trans);
1617 } else if (new_size < old_size) {
1618 ret = btrfs_shrink_device(device, new_size);
1619 } /* equal, nothing need to do */
1621 out_free:
1622 kfree(vol_args);
1623 out:
1624 mutex_unlock(&fs_info->volume_mutex);
1625 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
1626 mnt_drop_write_file(file);
1627 return ret;
1630 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1631 char *name, unsigned long fd, int subvol,
1632 u64 *transid, bool readonly,
1633 struct btrfs_qgroup_inherit *inherit)
1635 int namelen;
1636 int ret = 0;
1638 if (!S_ISDIR(file_inode(file)->i_mode))
1639 return -ENOTDIR;
1641 ret = mnt_want_write_file(file);
1642 if (ret)
1643 goto out;
1645 namelen = strlen(name);
1646 if (strchr(name, '/')) {
1647 ret = -EINVAL;
1648 goto out_drop_write;
1651 if (name[0] == '.' &&
1652 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1653 ret = -EEXIST;
1654 goto out_drop_write;
1657 if (subvol) {
1658 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1659 NULL, transid, readonly, inherit);
1660 } else {
1661 struct fd src = fdget(fd);
1662 struct inode *src_inode;
1663 if (!src.file) {
1664 ret = -EINVAL;
1665 goto out_drop_write;
1668 src_inode = file_inode(src.file);
1669 if (src_inode->i_sb != file_inode(file)->i_sb) {
1670 btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
1671 "Snapshot src from another FS");
1672 ret = -EXDEV;
1673 } else if (!inode_owner_or_capable(src_inode)) {
1675 * Subvolume creation is not restricted, but snapshots
1676 * are limited to own subvolumes only
1678 ret = -EPERM;
1679 } else {
1680 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1681 BTRFS_I(src_inode)->root,
1682 transid, readonly, inherit);
1684 fdput(src);
1686 out_drop_write:
1687 mnt_drop_write_file(file);
1688 out:
1689 return ret;
1692 static noinline int btrfs_ioctl_snap_create(struct file *file,
1693 void __user *arg, int subvol)
1695 struct btrfs_ioctl_vol_args *vol_args;
1696 int ret;
1698 if (!S_ISDIR(file_inode(file)->i_mode))
1699 return -ENOTDIR;
1701 vol_args = memdup_user(arg, sizeof(*vol_args));
1702 if (IS_ERR(vol_args))
1703 return PTR_ERR(vol_args);
1704 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1706 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1707 vol_args->fd, subvol,
1708 NULL, false, NULL);
1710 kfree(vol_args);
1711 return ret;
1714 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1715 void __user *arg, int subvol)
1717 struct btrfs_ioctl_vol_args_v2 *vol_args;
1718 int ret;
1719 u64 transid = 0;
1720 u64 *ptr = NULL;
1721 bool readonly = false;
1722 struct btrfs_qgroup_inherit *inherit = NULL;
1724 if (!S_ISDIR(file_inode(file)->i_mode))
1725 return -ENOTDIR;
1727 vol_args = memdup_user(arg, sizeof(*vol_args));
1728 if (IS_ERR(vol_args))
1729 return PTR_ERR(vol_args);
1730 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1732 if (vol_args->flags &
1733 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1734 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1735 ret = -EOPNOTSUPP;
1736 goto free_args;
1739 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1740 ptr = &transid;
1741 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1742 readonly = true;
1743 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1744 if (vol_args->size > PAGE_SIZE) {
1745 ret = -EINVAL;
1746 goto free_args;
1748 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1749 if (IS_ERR(inherit)) {
1750 ret = PTR_ERR(inherit);
1751 goto free_args;
1755 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1756 vol_args->fd, subvol, ptr,
1757 readonly, inherit);
1758 if (ret)
1759 goto free_inherit;
1761 if (ptr && copy_to_user(arg +
1762 offsetof(struct btrfs_ioctl_vol_args_v2,
1763 transid),
1764 ptr, sizeof(*ptr)))
1765 ret = -EFAULT;
1767 free_inherit:
1768 kfree(inherit);
1769 free_args:
1770 kfree(vol_args);
1771 return ret;
1774 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1775 void __user *arg)
1777 struct inode *inode = file_inode(file);
1778 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1779 struct btrfs_root *root = BTRFS_I(inode)->root;
1780 int ret = 0;
1781 u64 flags = 0;
1783 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)
1784 return -EINVAL;
1786 down_read(&fs_info->subvol_sem);
1787 if (btrfs_root_readonly(root))
1788 flags |= BTRFS_SUBVOL_RDONLY;
1789 up_read(&fs_info->subvol_sem);
1791 if (copy_to_user(arg, &flags, sizeof(flags)))
1792 ret = -EFAULT;
1794 return ret;
1797 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1798 void __user *arg)
1800 struct inode *inode = file_inode(file);
1801 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1802 struct btrfs_root *root = BTRFS_I(inode)->root;
1803 struct btrfs_trans_handle *trans;
1804 u64 root_flags;
1805 u64 flags;
1806 int ret = 0;
1808 if (!inode_owner_or_capable(inode))
1809 return -EPERM;
1811 ret = mnt_want_write_file(file);
1812 if (ret)
1813 goto out;
1815 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
1816 ret = -EINVAL;
1817 goto out_drop_write;
1820 if (copy_from_user(&flags, arg, sizeof(flags))) {
1821 ret = -EFAULT;
1822 goto out_drop_write;
1825 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1826 ret = -EINVAL;
1827 goto out_drop_write;
1830 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1831 ret = -EOPNOTSUPP;
1832 goto out_drop_write;
1835 down_write(&fs_info->subvol_sem);
1837 /* nothing to do */
1838 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1839 goto out_drop_sem;
1841 root_flags = btrfs_root_flags(&root->root_item);
1842 if (flags & BTRFS_SUBVOL_RDONLY) {
1843 btrfs_set_root_flags(&root->root_item,
1844 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1845 } else {
1847 * Block RO -> RW transition if this subvolume is involved in
1848 * send
1850 spin_lock(&root->root_item_lock);
1851 if (root->send_in_progress == 0) {
1852 btrfs_set_root_flags(&root->root_item,
1853 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1854 spin_unlock(&root->root_item_lock);
1855 } else {
1856 spin_unlock(&root->root_item_lock);
1857 btrfs_warn(fs_info,
1858 "Attempt to set subvolume %llu read-write during send",
1859 root->root_key.objectid);
1860 ret = -EPERM;
1861 goto out_drop_sem;
1865 trans = btrfs_start_transaction(root, 1);
1866 if (IS_ERR(trans)) {
1867 ret = PTR_ERR(trans);
1868 goto out_reset;
1871 ret = btrfs_update_root(trans, fs_info->tree_root,
1872 &root->root_key, &root->root_item);
1874 btrfs_commit_transaction(trans);
1875 out_reset:
1876 if (ret)
1877 btrfs_set_root_flags(&root->root_item, root_flags);
1878 out_drop_sem:
1879 up_write(&fs_info->subvol_sem);
1880 out_drop_write:
1881 mnt_drop_write_file(file);
1882 out:
1883 return ret;
1887 * helper to check if the subvolume references other subvolumes
1889 static noinline int may_destroy_subvol(struct btrfs_root *root)
1891 struct btrfs_fs_info *fs_info = root->fs_info;
1892 struct btrfs_path *path;
1893 struct btrfs_dir_item *di;
1894 struct btrfs_key key;
1895 u64 dir_id;
1896 int ret;
1898 path = btrfs_alloc_path();
1899 if (!path)
1900 return -ENOMEM;
1902 /* Make sure this root isn't set as the default subvol */
1903 dir_id = btrfs_super_root_dir(fs_info->super_copy);
1904 di = btrfs_lookup_dir_item(NULL, fs_info->tree_root, path,
1905 dir_id, "default", 7, 0);
1906 if (di && !IS_ERR(di)) {
1907 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1908 if (key.objectid == root->root_key.objectid) {
1909 ret = -EPERM;
1910 btrfs_err(fs_info,
1911 "deleting default subvolume %llu is not allowed",
1912 key.objectid);
1913 goto out;
1915 btrfs_release_path(path);
1918 key.objectid = root->root_key.objectid;
1919 key.type = BTRFS_ROOT_REF_KEY;
1920 key.offset = (u64)-1;
1922 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
1923 if (ret < 0)
1924 goto out;
1925 BUG_ON(ret == 0);
1927 ret = 0;
1928 if (path->slots[0] > 0) {
1929 path->slots[0]--;
1930 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1931 if (key.objectid == root->root_key.objectid &&
1932 key.type == BTRFS_ROOT_REF_KEY)
1933 ret = -ENOTEMPTY;
1935 out:
1936 btrfs_free_path(path);
1937 return ret;
1940 static noinline int key_in_sk(struct btrfs_key *key,
1941 struct btrfs_ioctl_search_key *sk)
1943 struct btrfs_key test;
1944 int ret;
1946 test.objectid = sk->min_objectid;
1947 test.type = sk->min_type;
1948 test.offset = sk->min_offset;
1950 ret = btrfs_comp_cpu_keys(key, &test);
1951 if (ret < 0)
1952 return 0;
1954 test.objectid = sk->max_objectid;
1955 test.type = sk->max_type;
1956 test.offset = sk->max_offset;
1958 ret = btrfs_comp_cpu_keys(key, &test);
1959 if (ret > 0)
1960 return 0;
1961 return 1;
1964 static noinline int copy_to_sk(struct btrfs_path *path,
1965 struct btrfs_key *key,
1966 struct btrfs_ioctl_search_key *sk,
1967 size_t *buf_size,
1968 char __user *ubuf,
1969 unsigned long *sk_offset,
1970 int *num_found)
1972 u64 found_transid;
1973 struct extent_buffer *leaf;
1974 struct btrfs_ioctl_search_header sh;
1975 struct btrfs_key test;
1976 unsigned long item_off;
1977 unsigned long item_len;
1978 int nritems;
1979 int i;
1980 int slot;
1981 int ret = 0;
1983 leaf = path->nodes[0];
1984 slot = path->slots[0];
1985 nritems = btrfs_header_nritems(leaf);
1987 if (btrfs_header_generation(leaf) > sk->max_transid) {
1988 i = nritems;
1989 goto advance_key;
1991 found_transid = btrfs_header_generation(leaf);
1993 for (i = slot; i < nritems; i++) {
1994 item_off = btrfs_item_ptr_offset(leaf, i);
1995 item_len = btrfs_item_size_nr(leaf, i);
1997 btrfs_item_key_to_cpu(leaf, key, i);
1998 if (!key_in_sk(key, sk))
1999 continue;
2001 if (sizeof(sh) + item_len > *buf_size) {
2002 if (*num_found) {
2003 ret = 1;
2004 goto out;
2008 * return one empty item back for v1, which does not
2009 * handle -EOVERFLOW
2012 *buf_size = sizeof(sh) + item_len;
2013 item_len = 0;
2014 ret = -EOVERFLOW;
2017 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2018 ret = 1;
2019 goto out;
2022 sh.objectid = key->objectid;
2023 sh.offset = key->offset;
2024 sh.type = key->type;
2025 sh.len = item_len;
2026 sh.transid = found_transid;
2028 /* copy search result header */
2029 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
2030 ret = -EFAULT;
2031 goto out;
2034 *sk_offset += sizeof(sh);
2036 if (item_len) {
2037 char __user *up = ubuf + *sk_offset;
2038 /* copy the item */
2039 if (read_extent_buffer_to_user(leaf, up,
2040 item_off, item_len)) {
2041 ret = -EFAULT;
2042 goto out;
2045 *sk_offset += item_len;
2047 (*num_found)++;
2049 if (ret) /* -EOVERFLOW from above */
2050 goto out;
2052 if (*num_found >= sk->nr_items) {
2053 ret = 1;
2054 goto out;
2057 advance_key:
2058 ret = 0;
2059 test.objectid = sk->max_objectid;
2060 test.type = sk->max_type;
2061 test.offset = sk->max_offset;
2062 if (btrfs_comp_cpu_keys(key, &test) >= 0)
2063 ret = 1;
2064 else if (key->offset < (u64)-1)
2065 key->offset++;
2066 else if (key->type < (u8)-1) {
2067 key->offset = 0;
2068 key->type++;
2069 } else if (key->objectid < (u64)-1) {
2070 key->offset = 0;
2071 key->type = 0;
2072 key->objectid++;
2073 } else
2074 ret = 1;
2075 out:
2077 * 0: all items from this leaf copied, continue with next
2078 * 1: * more items can be copied, but unused buffer is too small
2079 * * all items were found
2080 * Either way, it will stops the loop which iterates to the next
2081 * leaf
2082 * -EOVERFLOW: item was to large for buffer
2083 * -EFAULT: could not copy extent buffer back to userspace
2085 return ret;
2088 static noinline int search_ioctl(struct inode *inode,
2089 struct btrfs_ioctl_search_key *sk,
2090 size_t *buf_size,
2091 char __user *ubuf)
2093 struct btrfs_fs_info *info = btrfs_sb(inode->i_sb);
2094 struct btrfs_root *root;
2095 struct btrfs_key key;
2096 struct btrfs_path *path;
2097 int ret;
2098 int num_found = 0;
2099 unsigned long sk_offset = 0;
2101 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2102 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2103 return -EOVERFLOW;
2106 path = btrfs_alloc_path();
2107 if (!path)
2108 return -ENOMEM;
2110 if (sk->tree_id == 0) {
2111 /* search the root of the inode that was passed */
2112 root = BTRFS_I(inode)->root;
2113 } else {
2114 key.objectid = sk->tree_id;
2115 key.type = BTRFS_ROOT_ITEM_KEY;
2116 key.offset = (u64)-1;
2117 root = btrfs_read_fs_root_no_name(info, &key);
2118 if (IS_ERR(root)) {
2119 btrfs_free_path(path);
2120 return -ENOENT;
2124 key.objectid = sk->min_objectid;
2125 key.type = sk->min_type;
2126 key.offset = sk->min_offset;
2128 while (1) {
2129 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2130 if (ret != 0) {
2131 if (ret > 0)
2132 ret = 0;
2133 goto err;
2135 ret = copy_to_sk(path, &key, sk, buf_size, ubuf,
2136 &sk_offset, &num_found);
2137 btrfs_release_path(path);
2138 if (ret)
2139 break;
2142 if (ret > 0)
2143 ret = 0;
2144 err:
2145 sk->nr_items = num_found;
2146 btrfs_free_path(path);
2147 return ret;
2150 static noinline int btrfs_ioctl_tree_search(struct file *file,
2151 void __user *argp)
2153 struct btrfs_ioctl_search_args __user *uargs;
2154 struct btrfs_ioctl_search_key sk;
2155 struct inode *inode;
2156 int ret;
2157 size_t buf_size;
2159 if (!capable(CAP_SYS_ADMIN))
2160 return -EPERM;
2162 uargs = (struct btrfs_ioctl_search_args __user *)argp;
2164 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2165 return -EFAULT;
2167 buf_size = sizeof(uargs->buf);
2169 inode = file_inode(file);
2170 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2173 * In the origin implementation an overflow is handled by returning a
2174 * search header with a len of zero, so reset ret.
2176 if (ret == -EOVERFLOW)
2177 ret = 0;
2179 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2180 ret = -EFAULT;
2181 return ret;
2184 static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2185 void __user *argp)
2187 struct btrfs_ioctl_search_args_v2 __user *uarg;
2188 struct btrfs_ioctl_search_args_v2 args;
2189 struct inode *inode;
2190 int ret;
2191 size_t buf_size;
2192 const size_t buf_limit = SZ_16M;
2194 if (!capable(CAP_SYS_ADMIN))
2195 return -EPERM;
2197 /* copy search header and buffer size */
2198 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2199 if (copy_from_user(&args, uarg, sizeof(args)))
2200 return -EFAULT;
2202 buf_size = args.buf_size;
2204 if (buf_size < sizeof(struct btrfs_ioctl_search_header))
2205 return -EOVERFLOW;
2207 /* limit result size to 16MB */
2208 if (buf_size > buf_limit)
2209 buf_size = buf_limit;
2211 inode = file_inode(file);
2212 ret = search_ioctl(inode, &args.key, &buf_size,
2213 (char *)(&uarg->buf[0]));
2214 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2215 ret = -EFAULT;
2216 else if (ret == -EOVERFLOW &&
2217 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2218 ret = -EFAULT;
2220 return ret;
2224 * Search INODE_REFs to identify path name of 'dirid' directory
2225 * in a 'tree_id' tree. and sets path name to 'name'.
2227 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2228 u64 tree_id, u64 dirid, char *name)
2230 struct btrfs_root *root;
2231 struct btrfs_key key;
2232 char *ptr;
2233 int ret = -1;
2234 int slot;
2235 int len;
2236 int total_len = 0;
2237 struct btrfs_inode_ref *iref;
2238 struct extent_buffer *l;
2239 struct btrfs_path *path;
2241 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2242 name[0]='\0';
2243 return 0;
2246 path = btrfs_alloc_path();
2247 if (!path)
2248 return -ENOMEM;
2250 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2252 key.objectid = tree_id;
2253 key.type = BTRFS_ROOT_ITEM_KEY;
2254 key.offset = (u64)-1;
2255 root = btrfs_read_fs_root_no_name(info, &key);
2256 if (IS_ERR(root)) {
2257 btrfs_err(info, "could not find root %llu", tree_id);
2258 ret = -ENOENT;
2259 goto out;
2262 key.objectid = dirid;
2263 key.type = BTRFS_INODE_REF_KEY;
2264 key.offset = (u64)-1;
2266 while (1) {
2267 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2268 if (ret < 0)
2269 goto out;
2270 else if (ret > 0) {
2271 ret = btrfs_previous_item(root, path, dirid,
2272 BTRFS_INODE_REF_KEY);
2273 if (ret < 0)
2274 goto out;
2275 else if (ret > 0) {
2276 ret = -ENOENT;
2277 goto out;
2281 l = path->nodes[0];
2282 slot = path->slots[0];
2283 btrfs_item_key_to_cpu(l, &key, slot);
2285 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2286 len = btrfs_inode_ref_name_len(l, iref);
2287 ptr -= len + 1;
2288 total_len += len + 1;
2289 if (ptr < name) {
2290 ret = -ENAMETOOLONG;
2291 goto out;
2294 *(ptr + len) = '/';
2295 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2297 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2298 break;
2300 btrfs_release_path(path);
2301 key.objectid = key.offset;
2302 key.offset = (u64)-1;
2303 dirid = key.objectid;
2305 memmove(name, ptr, total_len);
2306 name[total_len] = '\0';
2307 ret = 0;
2308 out:
2309 btrfs_free_path(path);
2310 return ret;
2313 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2314 void __user *argp)
2316 struct btrfs_ioctl_ino_lookup_args *args;
2317 struct inode *inode;
2318 int ret = 0;
2320 args = memdup_user(argp, sizeof(*args));
2321 if (IS_ERR(args))
2322 return PTR_ERR(args);
2324 inode = file_inode(file);
2327 * Unprivileged query to obtain the containing subvolume root id. The
2328 * path is reset so it's consistent with btrfs_search_path_in_tree.
2330 if (args->treeid == 0)
2331 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2333 if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2334 args->name[0] = 0;
2335 goto out;
2338 if (!capable(CAP_SYS_ADMIN)) {
2339 ret = -EPERM;
2340 goto out;
2343 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2344 args->treeid, args->objectid,
2345 args->name);
2347 out:
2348 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2349 ret = -EFAULT;
2351 kfree(args);
2352 return ret;
2355 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2356 void __user *arg)
2358 struct dentry *parent = file->f_path.dentry;
2359 struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb);
2360 struct dentry *dentry;
2361 struct inode *dir = d_inode(parent);
2362 struct inode *inode;
2363 struct btrfs_root *root = BTRFS_I(dir)->root;
2364 struct btrfs_root *dest = NULL;
2365 struct btrfs_ioctl_vol_args *vol_args;
2366 struct btrfs_trans_handle *trans;
2367 struct btrfs_block_rsv block_rsv;
2368 u64 root_flags;
2369 u64 qgroup_reserved;
2370 int namelen;
2371 int ret;
2372 int err = 0;
2374 if (!S_ISDIR(dir->i_mode))
2375 return -ENOTDIR;
2377 vol_args = memdup_user(arg, sizeof(*vol_args));
2378 if (IS_ERR(vol_args))
2379 return PTR_ERR(vol_args);
2381 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2382 namelen = strlen(vol_args->name);
2383 if (strchr(vol_args->name, '/') ||
2384 strncmp(vol_args->name, "..", namelen) == 0) {
2385 err = -EINVAL;
2386 goto out;
2389 err = mnt_want_write_file(file);
2390 if (err)
2391 goto out;
2394 err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
2395 if (err == -EINTR)
2396 goto out_drop_write;
2397 dentry = lookup_one_len(vol_args->name, parent, namelen);
2398 if (IS_ERR(dentry)) {
2399 err = PTR_ERR(dentry);
2400 goto out_unlock_dir;
2403 if (d_really_is_negative(dentry)) {
2404 err = -ENOENT;
2405 goto out_dput;
2408 inode = d_inode(dentry);
2409 dest = BTRFS_I(inode)->root;
2410 if (!capable(CAP_SYS_ADMIN)) {
2412 * Regular user. Only allow this with a special mount
2413 * option, when the user has write+exec access to the
2414 * subvol root, and when rmdir(2) would have been
2415 * allowed.
2417 * Note that this is _not_ check that the subvol is
2418 * empty or doesn't contain data that we wouldn't
2419 * otherwise be able to delete.
2421 * Users who want to delete empty subvols should try
2422 * rmdir(2).
2424 err = -EPERM;
2425 if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))
2426 goto out_dput;
2429 * Do not allow deletion if the parent dir is the same
2430 * as the dir to be deleted. That means the ioctl
2431 * must be called on the dentry referencing the root
2432 * of the subvol, not a random directory contained
2433 * within it.
2435 err = -EINVAL;
2436 if (root == dest)
2437 goto out_dput;
2439 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2440 if (err)
2441 goto out_dput;
2444 /* check if subvolume may be deleted by a user */
2445 err = btrfs_may_delete(dir, dentry, 1);
2446 if (err)
2447 goto out_dput;
2449 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
2450 err = -EINVAL;
2451 goto out_dput;
2454 inode_lock(inode);
2457 * Don't allow to delete a subvolume with send in progress. This is
2458 * inside the i_mutex so the error handling that has to drop the bit
2459 * again is not run concurrently.
2461 spin_lock(&dest->root_item_lock);
2462 root_flags = btrfs_root_flags(&dest->root_item);
2463 if (dest->send_in_progress == 0) {
2464 btrfs_set_root_flags(&dest->root_item,
2465 root_flags | BTRFS_ROOT_SUBVOL_DEAD);
2466 spin_unlock(&dest->root_item_lock);
2467 } else {
2468 spin_unlock(&dest->root_item_lock);
2469 btrfs_warn(fs_info,
2470 "Attempt to delete subvolume %llu during send",
2471 dest->root_key.objectid);
2472 err = -EPERM;
2473 goto out_unlock_inode;
2476 down_write(&fs_info->subvol_sem);
2478 err = may_destroy_subvol(dest);
2479 if (err)
2480 goto out_up_write;
2482 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2484 * One for dir inode, two for dir entries, two for root
2485 * ref/backref.
2487 err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2488 5, &qgroup_reserved, true);
2489 if (err)
2490 goto out_up_write;
2492 trans = btrfs_start_transaction(root, 0);
2493 if (IS_ERR(trans)) {
2494 err = PTR_ERR(trans);
2495 goto out_release;
2497 trans->block_rsv = &block_rsv;
2498 trans->bytes_reserved = block_rsv.size;
2500 btrfs_record_snapshot_destroy(trans, BTRFS_I(dir));
2502 ret = btrfs_unlink_subvol(trans, root, dir,
2503 dest->root_key.objectid,
2504 dentry->d_name.name,
2505 dentry->d_name.len);
2506 if (ret) {
2507 err = ret;
2508 btrfs_abort_transaction(trans, ret);
2509 goto out_end_trans;
2512 btrfs_record_root_in_trans(trans, dest);
2514 memset(&dest->root_item.drop_progress, 0,
2515 sizeof(dest->root_item.drop_progress));
2516 dest->root_item.drop_level = 0;
2517 btrfs_set_root_refs(&dest->root_item, 0);
2519 if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
2520 ret = btrfs_insert_orphan_item(trans,
2521 fs_info->tree_root,
2522 dest->root_key.objectid);
2523 if (ret) {
2524 btrfs_abort_transaction(trans, ret);
2525 err = ret;
2526 goto out_end_trans;
2530 ret = btrfs_uuid_tree_rem(trans, fs_info, dest->root_item.uuid,
2531 BTRFS_UUID_KEY_SUBVOL,
2532 dest->root_key.objectid);
2533 if (ret && ret != -ENOENT) {
2534 btrfs_abort_transaction(trans, ret);
2535 err = ret;
2536 goto out_end_trans;
2538 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
2539 ret = btrfs_uuid_tree_rem(trans, fs_info,
2540 dest->root_item.received_uuid,
2541 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
2542 dest->root_key.objectid);
2543 if (ret && ret != -ENOENT) {
2544 btrfs_abort_transaction(trans, ret);
2545 err = ret;
2546 goto out_end_trans;
2550 out_end_trans:
2551 trans->block_rsv = NULL;
2552 trans->bytes_reserved = 0;
2553 ret = btrfs_end_transaction(trans);
2554 if (ret && !err)
2555 err = ret;
2556 inode->i_flags |= S_DEAD;
2557 out_release:
2558 btrfs_subvolume_release_metadata(fs_info, &block_rsv, qgroup_reserved);
2559 out_up_write:
2560 up_write(&fs_info->subvol_sem);
2561 if (err) {
2562 spin_lock(&dest->root_item_lock);
2563 root_flags = btrfs_root_flags(&dest->root_item);
2564 btrfs_set_root_flags(&dest->root_item,
2565 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
2566 spin_unlock(&dest->root_item_lock);
2568 out_unlock_inode:
2569 inode_unlock(inode);
2570 if (!err) {
2571 d_invalidate(dentry);
2572 btrfs_invalidate_inodes(dest);
2573 d_delete(dentry);
2574 ASSERT(dest->send_in_progress == 0);
2576 /* the last ref */
2577 if (dest->ino_cache_inode) {
2578 iput(dest->ino_cache_inode);
2579 dest->ino_cache_inode = NULL;
2582 out_dput:
2583 dput(dentry);
2584 out_unlock_dir:
2585 inode_unlock(dir);
2586 out_drop_write:
2587 mnt_drop_write_file(file);
2588 out:
2589 kfree(vol_args);
2590 return err;
2593 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2595 struct inode *inode = file_inode(file);
2596 struct btrfs_root *root = BTRFS_I(inode)->root;
2597 struct btrfs_ioctl_defrag_range_args *range;
2598 int ret;
2600 ret = mnt_want_write_file(file);
2601 if (ret)
2602 return ret;
2604 if (btrfs_root_readonly(root)) {
2605 ret = -EROFS;
2606 goto out;
2609 switch (inode->i_mode & S_IFMT) {
2610 case S_IFDIR:
2611 if (!capable(CAP_SYS_ADMIN)) {
2612 ret = -EPERM;
2613 goto out;
2615 ret = btrfs_defrag_root(root);
2616 break;
2617 case S_IFREG:
2618 if (!(file->f_mode & FMODE_WRITE)) {
2619 ret = -EINVAL;
2620 goto out;
2623 range = kzalloc(sizeof(*range), GFP_KERNEL);
2624 if (!range) {
2625 ret = -ENOMEM;
2626 goto out;
2629 if (argp) {
2630 if (copy_from_user(range, argp,
2631 sizeof(*range))) {
2632 ret = -EFAULT;
2633 kfree(range);
2634 goto out;
2636 /* compression requires us to start the IO */
2637 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2638 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2639 range->extent_thresh = (u32)-1;
2641 } else {
2642 /* the rest are all set to zero by kzalloc */
2643 range->len = (u64)-1;
2645 ret = btrfs_defrag_file(file_inode(file), file,
2646 range, 0, 0);
2647 if (ret > 0)
2648 ret = 0;
2649 kfree(range);
2650 break;
2651 default:
2652 ret = -EINVAL;
2654 out:
2655 mnt_drop_write_file(file);
2656 return ret;
2659 static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg)
2661 struct btrfs_ioctl_vol_args *vol_args;
2662 int ret;
2664 if (!capable(CAP_SYS_ADMIN))
2665 return -EPERM;
2667 if (atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1))
2668 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2670 mutex_lock(&fs_info->volume_mutex);
2671 vol_args = memdup_user(arg, sizeof(*vol_args));
2672 if (IS_ERR(vol_args)) {
2673 ret = PTR_ERR(vol_args);
2674 goto out;
2677 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2678 ret = btrfs_init_new_device(fs_info, vol_args->name);
2680 if (!ret)
2681 btrfs_info(fs_info, "disk added %s", vol_args->name);
2683 kfree(vol_args);
2684 out:
2685 mutex_unlock(&fs_info->volume_mutex);
2686 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
2687 return ret;
2690 static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
2692 struct inode *inode = file_inode(file);
2693 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2694 struct btrfs_ioctl_vol_args_v2 *vol_args;
2695 int ret;
2697 if (!capable(CAP_SYS_ADMIN))
2698 return -EPERM;
2700 ret = mnt_want_write_file(file);
2701 if (ret)
2702 return ret;
2704 vol_args = memdup_user(arg, sizeof(*vol_args));
2705 if (IS_ERR(vol_args)) {
2706 ret = PTR_ERR(vol_args);
2707 goto err_drop;
2710 /* Check for compatibility reject unknown flags */
2711 if (vol_args->flags & ~BTRFS_VOL_ARG_V2_FLAGS_SUPPORTED)
2712 return -EOPNOTSUPP;
2714 if (atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
2715 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2716 goto out;
2719 mutex_lock(&fs_info->volume_mutex);
2720 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
2721 ret = btrfs_rm_device(fs_info, NULL, vol_args->devid);
2722 } else {
2723 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
2724 ret = btrfs_rm_device(fs_info, vol_args->name, 0);
2726 mutex_unlock(&fs_info->volume_mutex);
2727 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
2729 if (!ret) {
2730 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
2731 btrfs_info(fs_info, "device deleted: id %llu",
2732 vol_args->devid);
2733 else
2734 btrfs_info(fs_info, "device deleted: %s",
2735 vol_args->name);
2737 out:
2738 kfree(vol_args);
2739 err_drop:
2740 mnt_drop_write_file(file);
2741 return ret;
2744 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2746 struct inode *inode = file_inode(file);
2747 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2748 struct btrfs_ioctl_vol_args *vol_args;
2749 int ret;
2751 if (!capable(CAP_SYS_ADMIN))
2752 return -EPERM;
2754 ret = mnt_want_write_file(file);
2755 if (ret)
2756 return ret;
2758 if (atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
2759 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2760 goto out_drop_write;
2763 vol_args = memdup_user(arg, sizeof(*vol_args));
2764 if (IS_ERR(vol_args)) {
2765 ret = PTR_ERR(vol_args);
2766 goto out;
2769 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2770 mutex_lock(&fs_info->volume_mutex);
2771 ret = btrfs_rm_device(fs_info, vol_args->name, 0);
2772 mutex_unlock(&fs_info->volume_mutex);
2774 if (!ret)
2775 btrfs_info(fs_info, "disk deleted %s", vol_args->name);
2776 kfree(vol_args);
2777 out:
2778 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
2779 out_drop_write:
2780 mnt_drop_write_file(file);
2782 return ret;
2785 static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,
2786 void __user *arg)
2788 struct btrfs_ioctl_fs_info_args *fi_args;
2789 struct btrfs_device *device;
2790 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2791 int ret = 0;
2793 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2794 if (!fi_args)
2795 return -ENOMEM;
2797 mutex_lock(&fs_devices->device_list_mutex);
2798 fi_args->num_devices = fs_devices->num_devices;
2799 memcpy(&fi_args->fsid, fs_info->fsid, sizeof(fi_args->fsid));
2801 list_for_each_entry(device, &fs_devices->devices, dev_list) {
2802 if (device->devid > fi_args->max_id)
2803 fi_args->max_id = device->devid;
2805 mutex_unlock(&fs_devices->device_list_mutex);
2807 fi_args->nodesize = fs_info->super_copy->nodesize;
2808 fi_args->sectorsize = fs_info->super_copy->sectorsize;
2809 fi_args->clone_alignment = fs_info->super_copy->sectorsize;
2811 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2812 ret = -EFAULT;
2814 kfree(fi_args);
2815 return ret;
2818 static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,
2819 void __user *arg)
2821 struct btrfs_ioctl_dev_info_args *di_args;
2822 struct btrfs_device *dev;
2823 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2824 int ret = 0;
2825 char *s_uuid = NULL;
2827 di_args = memdup_user(arg, sizeof(*di_args));
2828 if (IS_ERR(di_args))
2829 return PTR_ERR(di_args);
2831 if (!btrfs_is_empty_uuid(di_args->uuid))
2832 s_uuid = di_args->uuid;
2834 mutex_lock(&fs_devices->device_list_mutex);
2835 dev = btrfs_find_device(fs_info, di_args->devid, s_uuid, NULL);
2837 if (!dev) {
2838 ret = -ENODEV;
2839 goto out;
2842 di_args->devid = dev->devid;
2843 di_args->bytes_used = btrfs_device_get_bytes_used(dev);
2844 di_args->total_bytes = btrfs_device_get_total_bytes(dev);
2845 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2846 if (dev->name) {
2847 struct rcu_string *name;
2849 rcu_read_lock();
2850 name = rcu_dereference(dev->name);
2851 strncpy(di_args->path, name->str, sizeof(di_args->path));
2852 rcu_read_unlock();
2853 di_args->path[sizeof(di_args->path) - 1] = 0;
2854 } else {
2855 di_args->path[0] = '\0';
2858 out:
2859 mutex_unlock(&fs_devices->device_list_mutex);
2860 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2861 ret = -EFAULT;
2863 kfree(di_args);
2864 return ret;
2867 static struct page *extent_same_get_page(struct inode *inode, pgoff_t index)
2869 struct page *page;
2871 page = grab_cache_page(inode->i_mapping, index);
2872 if (!page)
2873 return ERR_PTR(-ENOMEM);
2875 if (!PageUptodate(page)) {
2876 int ret;
2878 ret = btrfs_readpage(NULL, page);
2879 if (ret)
2880 return ERR_PTR(ret);
2881 lock_page(page);
2882 if (!PageUptodate(page)) {
2883 unlock_page(page);
2884 put_page(page);
2885 return ERR_PTR(-EIO);
2887 if (page->mapping != inode->i_mapping) {
2888 unlock_page(page);
2889 put_page(page);
2890 return ERR_PTR(-EAGAIN);
2894 return page;
2897 static int gather_extent_pages(struct inode *inode, struct page **pages,
2898 int num_pages, u64 off)
2900 int i;
2901 pgoff_t index = off >> PAGE_SHIFT;
2903 for (i = 0; i < num_pages; i++) {
2904 again:
2905 pages[i] = extent_same_get_page(inode, index + i);
2906 if (IS_ERR(pages[i])) {
2907 int err = PTR_ERR(pages[i]);
2909 if (err == -EAGAIN)
2910 goto again;
2911 pages[i] = NULL;
2912 return err;
2915 return 0;
2918 static int lock_extent_range(struct inode *inode, u64 off, u64 len,
2919 bool retry_range_locking)
2922 * Do any pending delalloc/csum calculations on inode, one way or
2923 * another, and lock file content.
2924 * The locking order is:
2926 * 1) pages
2927 * 2) range in the inode's io tree
2929 while (1) {
2930 struct btrfs_ordered_extent *ordered;
2931 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2932 ordered = btrfs_lookup_first_ordered_extent(inode,
2933 off + len - 1);
2934 if ((!ordered ||
2935 ordered->file_offset + ordered->len <= off ||
2936 ordered->file_offset >= off + len) &&
2937 !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2938 off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
2939 if (ordered)
2940 btrfs_put_ordered_extent(ordered);
2941 break;
2943 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2944 if (ordered)
2945 btrfs_put_ordered_extent(ordered);
2946 if (!retry_range_locking)
2947 return -EAGAIN;
2948 btrfs_wait_ordered_range(inode, off, len);
2950 return 0;
2953 static void btrfs_double_inode_unlock(struct inode *inode1, struct inode *inode2)
2955 inode_unlock(inode1);
2956 inode_unlock(inode2);
2959 static void btrfs_double_inode_lock(struct inode *inode1, struct inode *inode2)
2961 if (inode1 < inode2)
2962 swap(inode1, inode2);
2964 inode_lock_nested(inode1, I_MUTEX_PARENT);
2965 inode_lock_nested(inode2, I_MUTEX_CHILD);
2968 static void btrfs_double_extent_unlock(struct inode *inode1, u64 loff1,
2969 struct inode *inode2, u64 loff2, u64 len)
2971 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
2972 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
2975 static int btrfs_double_extent_lock(struct inode *inode1, u64 loff1,
2976 struct inode *inode2, u64 loff2, u64 len,
2977 bool retry_range_locking)
2979 int ret;
2981 if (inode1 < inode2) {
2982 swap(inode1, inode2);
2983 swap(loff1, loff2);
2985 ret = lock_extent_range(inode1, loff1, len, retry_range_locking);
2986 if (ret)
2987 return ret;
2988 ret = lock_extent_range(inode2, loff2, len, retry_range_locking);
2989 if (ret)
2990 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1,
2991 loff1 + len - 1);
2992 return ret;
2995 struct cmp_pages {
2996 int num_pages;
2997 struct page **src_pages;
2998 struct page **dst_pages;
3001 static void btrfs_cmp_data_free(struct cmp_pages *cmp)
3003 int i;
3004 struct page *pg;
3006 for (i = 0; i < cmp->num_pages; i++) {
3007 pg = cmp->src_pages[i];
3008 if (pg) {
3009 unlock_page(pg);
3010 put_page(pg);
3012 pg = cmp->dst_pages[i];
3013 if (pg) {
3014 unlock_page(pg);
3015 put_page(pg);
3018 kfree(cmp->src_pages);
3019 kfree(cmp->dst_pages);
3022 static int btrfs_cmp_data_prepare(struct inode *src, u64 loff,
3023 struct inode *dst, u64 dst_loff,
3024 u64 len, struct cmp_pages *cmp)
3026 int ret;
3027 int num_pages = PAGE_ALIGN(len) >> PAGE_SHIFT;
3028 struct page **src_pgarr, **dst_pgarr;
3031 * We must gather up all the pages before we initiate our
3032 * extent locking. We use an array for the page pointers. Size
3033 * of the array is bounded by len, which is in turn bounded by
3034 * BTRFS_MAX_DEDUPE_LEN.
3036 src_pgarr = kcalloc(num_pages, sizeof(struct page *), GFP_KERNEL);
3037 dst_pgarr = kcalloc(num_pages, sizeof(struct page *), GFP_KERNEL);
3038 if (!src_pgarr || !dst_pgarr) {
3039 kfree(src_pgarr);
3040 kfree(dst_pgarr);
3041 return -ENOMEM;
3043 cmp->num_pages = num_pages;
3044 cmp->src_pages = src_pgarr;
3045 cmp->dst_pages = dst_pgarr;
3047 ret = gather_extent_pages(src, cmp->src_pages, cmp->num_pages, loff);
3048 if (ret)
3049 goto out;
3051 ret = gather_extent_pages(dst, cmp->dst_pages, cmp->num_pages, dst_loff);
3053 out:
3054 if (ret)
3055 btrfs_cmp_data_free(cmp);
3056 return 0;
3059 static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
3060 u64 dst_loff, u64 len, struct cmp_pages *cmp)
3062 int ret = 0;
3063 int i;
3064 struct page *src_page, *dst_page;
3065 unsigned int cmp_len = PAGE_SIZE;
3066 void *addr, *dst_addr;
3068 i = 0;
3069 while (len) {
3070 if (len < PAGE_SIZE)
3071 cmp_len = len;
3073 BUG_ON(i >= cmp->num_pages);
3075 src_page = cmp->src_pages[i];
3076 dst_page = cmp->dst_pages[i];
3077 ASSERT(PageLocked(src_page));
3078 ASSERT(PageLocked(dst_page));
3080 addr = kmap_atomic(src_page);
3081 dst_addr = kmap_atomic(dst_page);
3083 flush_dcache_page(src_page);
3084 flush_dcache_page(dst_page);
3086 if (memcmp(addr, dst_addr, cmp_len))
3087 ret = -EBADE;
3089 kunmap_atomic(addr);
3090 kunmap_atomic(dst_addr);
3092 if (ret)
3093 break;
3095 len -= cmp_len;
3096 i++;
3099 return ret;
3102 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 *plen,
3103 u64 olen)
3105 u64 len = *plen;
3106 u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
3108 if (off + olen > inode->i_size || off + olen < off)
3109 return -EINVAL;
3111 /* if we extend to eof, continue to block boundary */
3112 if (off + len == inode->i_size)
3113 *plen = len = ALIGN(inode->i_size, bs) - off;
3115 /* Check that we are block aligned - btrfs_clone() requires this */
3116 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
3117 return -EINVAL;
3119 return 0;
3122 static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
3123 struct inode *dst, u64 dst_loff)
3125 int ret;
3126 u64 len = olen;
3127 struct cmp_pages cmp;
3128 int same_inode = 0;
3129 u64 same_lock_start = 0;
3130 u64 same_lock_len = 0;
3132 if (src == dst)
3133 same_inode = 1;
3135 if (len == 0)
3136 return 0;
3138 if (same_inode) {
3139 inode_lock(src);
3141 ret = extent_same_check_offsets(src, loff, &len, olen);
3142 if (ret)
3143 goto out_unlock;
3144 ret = extent_same_check_offsets(src, dst_loff, &len, olen);
3145 if (ret)
3146 goto out_unlock;
3149 * Single inode case wants the same checks, except we
3150 * don't want our length pushed out past i_size as
3151 * comparing that data range makes no sense.
3153 * extent_same_check_offsets() will do this for an
3154 * unaligned length at i_size, so catch it here and
3155 * reject the request.
3157 * This effectively means we require aligned extents
3158 * for the single-inode case, whereas the other cases
3159 * allow an unaligned length so long as it ends at
3160 * i_size.
3162 if (len != olen) {
3163 ret = -EINVAL;
3164 goto out_unlock;
3167 /* Check for overlapping ranges */
3168 if (dst_loff + len > loff && dst_loff < loff + len) {
3169 ret = -EINVAL;
3170 goto out_unlock;
3173 same_lock_start = min_t(u64, loff, dst_loff);
3174 same_lock_len = max_t(u64, loff, dst_loff) + len - same_lock_start;
3175 } else {
3176 btrfs_double_inode_lock(src, dst);
3178 ret = extent_same_check_offsets(src, loff, &len, olen);
3179 if (ret)
3180 goto out_unlock;
3182 ret = extent_same_check_offsets(dst, dst_loff, &len, olen);
3183 if (ret)
3184 goto out_unlock;
3187 /* don't make the dst file partly checksummed */
3188 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3189 (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
3190 ret = -EINVAL;
3191 goto out_unlock;
3194 again:
3195 ret = btrfs_cmp_data_prepare(src, loff, dst, dst_loff, olen, &cmp);
3196 if (ret)
3197 goto out_unlock;
3199 if (same_inode)
3200 ret = lock_extent_range(src, same_lock_start, same_lock_len,
3201 false);
3202 else
3203 ret = btrfs_double_extent_lock(src, loff, dst, dst_loff, len,
3204 false);
3206 * If one of the inodes has dirty pages in the respective range or
3207 * ordered extents, we need to flush dellaloc and wait for all ordered
3208 * extents in the range. We must unlock the pages and the ranges in the
3209 * io trees to avoid deadlocks when flushing delalloc (requires locking
3210 * pages) and when waiting for ordered extents to complete (they require
3211 * range locking).
3213 if (ret == -EAGAIN) {
3215 * Ranges in the io trees already unlocked. Now unlock all
3216 * pages before waiting for all IO to complete.
3218 btrfs_cmp_data_free(&cmp);
3219 if (same_inode) {
3220 btrfs_wait_ordered_range(src, same_lock_start,
3221 same_lock_len);
3222 } else {
3223 btrfs_wait_ordered_range(src, loff, len);
3224 btrfs_wait_ordered_range(dst, dst_loff, len);
3226 goto again;
3228 ASSERT(ret == 0);
3229 if (WARN_ON(ret)) {
3230 /* ranges in the io trees already unlocked */
3231 btrfs_cmp_data_free(&cmp);
3232 return ret;
3235 /* pass original length for comparison so we stay within i_size */
3236 ret = btrfs_cmp_data(src, loff, dst, dst_loff, olen, &cmp);
3237 if (ret == 0)
3238 ret = btrfs_clone(src, dst, loff, olen, len, dst_loff, 1);
3240 if (same_inode)
3241 unlock_extent(&BTRFS_I(src)->io_tree, same_lock_start,
3242 same_lock_start + same_lock_len - 1);
3243 else
3244 btrfs_double_extent_unlock(src, loff, dst, dst_loff, len);
3246 btrfs_cmp_data_free(&cmp);
3247 out_unlock:
3248 if (same_inode)
3249 inode_unlock(src);
3250 else
3251 btrfs_double_inode_unlock(src, dst);
3253 return ret;
3256 #define BTRFS_MAX_DEDUPE_LEN SZ_16M
3258 ssize_t btrfs_dedupe_file_range(struct file *src_file, u64 loff, u64 olen,
3259 struct file *dst_file, u64 dst_loff)
3261 struct inode *src = file_inode(src_file);
3262 struct inode *dst = file_inode(dst_file);
3263 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
3264 ssize_t res;
3266 if (olen > BTRFS_MAX_DEDUPE_LEN)
3267 olen = BTRFS_MAX_DEDUPE_LEN;
3269 if (WARN_ON_ONCE(bs < PAGE_SIZE)) {
3271 * Btrfs does not support blocksize < page_size. As a
3272 * result, btrfs_cmp_data() won't correctly handle
3273 * this situation without an update.
3275 return -EINVAL;
3278 res = btrfs_extent_same(src, loff, olen, dst, dst_loff);
3279 if (res)
3280 return res;
3281 return olen;
3284 static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3285 struct inode *inode,
3286 u64 endoff,
3287 const u64 destoff,
3288 const u64 olen,
3289 int no_time_update)
3291 struct btrfs_root *root = BTRFS_I(inode)->root;
3292 int ret;
3294 inode_inc_iversion(inode);
3295 if (!no_time_update)
3296 inode->i_mtime = inode->i_ctime = current_time(inode);
3298 * We round up to the block size at eof when determining which
3299 * extents to clone above, but shouldn't round up the file size.
3301 if (endoff > destoff + olen)
3302 endoff = destoff + olen;
3303 if (endoff > inode->i_size)
3304 btrfs_i_size_write(inode, endoff);
3306 ret = btrfs_update_inode(trans, root, inode);
3307 if (ret) {
3308 btrfs_abort_transaction(trans, ret);
3309 btrfs_end_transaction(trans);
3310 goto out;
3312 ret = btrfs_end_transaction(trans);
3313 out:
3314 return ret;
3317 static void clone_update_extent_map(struct inode *inode,
3318 const struct btrfs_trans_handle *trans,
3319 const struct btrfs_path *path,
3320 const u64 hole_offset,
3321 const u64 hole_len)
3323 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
3324 struct extent_map *em;
3325 int ret;
3327 em = alloc_extent_map();
3328 if (!em) {
3329 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3330 &BTRFS_I(inode)->runtime_flags);
3331 return;
3334 if (path) {
3335 struct btrfs_file_extent_item *fi;
3337 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
3338 struct btrfs_file_extent_item);
3339 btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
3340 em->generation = -1;
3341 if (btrfs_file_extent_type(path->nodes[0], fi) ==
3342 BTRFS_FILE_EXTENT_INLINE)
3343 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3344 &BTRFS_I(inode)->runtime_flags);
3345 } else {
3346 em->start = hole_offset;
3347 em->len = hole_len;
3348 em->ram_bytes = em->len;
3349 em->orig_start = hole_offset;
3350 em->block_start = EXTENT_MAP_HOLE;
3351 em->block_len = 0;
3352 em->orig_block_len = 0;
3353 em->compress_type = BTRFS_COMPRESS_NONE;
3354 em->generation = trans->transid;
3357 while (1) {
3358 write_lock(&em_tree->lock);
3359 ret = add_extent_mapping(em_tree, em, 1);
3360 write_unlock(&em_tree->lock);
3361 if (ret != -EEXIST) {
3362 free_extent_map(em);
3363 break;
3365 btrfs_drop_extent_cache(inode, em->start,
3366 em->start + em->len - 1, 0);
3369 if (ret)
3370 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3371 &BTRFS_I(inode)->runtime_flags);
3375 * Make sure we do not end up inserting an inline extent into a file that has
3376 * already other (non-inline) extents. If a file has an inline extent it can
3377 * not have any other extents and the (single) inline extent must start at the
3378 * file offset 0. Failing to respect these rules will lead to file corruption,
3379 * resulting in EIO errors on read/write operations, hitting BUG_ON's in mm, etc
3381 * We can have extents that have been already written to disk or we can have
3382 * dirty ranges still in delalloc, in which case the extent maps and items are
3383 * created only when we run delalloc, and the delalloc ranges might fall outside
3384 * the range we are currently locking in the inode's io tree. So we check the
3385 * inode's i_size because of that (i_size updates are done while holding the
3386 * i_mutex, which we are holding here).
3387 * We also check to see if the inode has a size not greater than "datal" but has
3388 * extents beyond it, due to an fallocate with FALLOC_FL_KEEP_SIZE (and we are
3389 * protected against such concurrent fallocate calls by the i_mutex).
3391 * If the file has no extents but a size greater than datal, do not allow the
3392 * copy because we would need turn the inline extent into a non-inline one (even
3393 * with NO_HOLES enabled). If we find our destination inode only has one inline
3394 * extent, just overwrite it with the source inline extent if its size is less
3395 * than the source extent's size, or we could copy the source inline extent's
3396 * data into the destination inode's inline extent if the later is greater then
3397 * the former.
3399 static int clone_copy_inline_extent(struct inode *src,
3400 struct inode *dst,
3401 struct btrfs_trans_handle *trans,
3402 struct btrfs_path *path,
3403 struct btrfs_key *new_key,
3404 const u64 drop_start,
3405 const u64 datal,
3406 const u64 skip,
3407 const u64 size,
3408 char *inline_data)
3410 struct btrfs_fs_info *fs_info = btrfs_sb(dst->i_sb);
3411 struct btrfs_root *root = BTRFS_I(dst)->root;
3412 const u64 aligned_end = ALIGN(new_key->offset + datal,
3413 fs_info->sectorsize);
3414 int ret;
3415 struct btrfs_key key;
3417 if (new_key->offset > 0)
3418 return -EOPNOTSUPP;
3420 key.objectid = btrfs_ino(BTRFS_I(dst));
3421 key.type = BTRFS_EXTENT_DATA_KEY;
3422 key.offset = 0;
3423 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3424 if (ret < 0) {
3425 return ret;
3426 } else if (ret > 0) {
3427 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
3428 ret = btrfs_next_leaf(root, path);
3429 if (ret < 0)
3430 return ret;
3431 else if (ret > 0)
3432 goto copy_inline_extent;
3434 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
3435 if (key.objectid == btrfs_ino(BTRFS_I(dst)) &&
3436 key.type == BTRFS_EXTENT_DATA_KEY) {
3437 ASSERT(key.offset > 0);
3438 return -EOPNOTSUPP;
3440 } else if (i_size_read(dst) <= datal) {
3441 struct btrfs_file_extent_item *ei;
3442 u64 ext_len;
3445 * If the file size is <= datal, make sure there are no other
3446 * extents following (can happen do to an fallocate call with
3447 * the flag FALLOC_FL_KEEP_SIZE).
3449 ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
3450 struct btrfs_file_extent_item);
3452 * If it's an inline extent, it can not have other extents
3453 * following it.
3455 if (btrfs_file_extent_type(path->nodes[0], ei) ==
3456 BTRFS_FILE_EXTENT_INLINE)
3457 goto copy_inline_extent;
3459 ext_len = btrfs_file_extent_num_bytes(path->nodes[0], ei);
3460 if (ext_len > aligned_end)
3461 return -EOPNOTSUPP;
3463 ret = btrfs_next_item(root, path);
3464 if (ret < 0) {
3465 return ret;
3466 } else if (ret == 0) {
3467 btrfs_item_key_to_cpu(path->nodes[0], &key,
3468 path->slots[0]);
3469 if (key.objectid == btrfs_ino(BTRFS_I(dst)) &&
3470 key.type == BTRFS_EXTENT_DATA_KEY)
3471 return -EOPNOTSUPP;
3475 copy_inline_extent:
3477 * We have no extent items, or we have an extent at offset 0 which may
3478 * or may not be inlined. All these cases are dealt the same way.
3480 if (i_size_read(dst) > datal) {
3482 * If the destination inode has an inline extent...
3483 * This would require copying the data from the source inline
3484 * extent into the beginning of the destination's inline extent.
3485 * But this is really complex, both extents can be compressed
3486 * or just one of them, which would require decompressing and
3487 * re-compressing data (which could increase the new compressed
3488 * size, not allowing the compressed data to fit anymore in an
3489 * inline extent).
3490 * So just don't support this case for now (it should be rare,
3491 * we are not really saving space when cloning inline extents).
3493 return -EOPNOTSUPP;
3496 btrfs_release_path(path);
3497 ret = btrfs_drop_extents(trans, root, dst, drop_start, aligned_end, 1);
3498 if (ret)
3499 return ret;
3500 ret = btrfs_insert_empty_item(trans, root, path, new_key, size);
3501 if (ret)
3502 return ret;
3504 if (skip) {
3505 const u32 start = btrfs_file_extent_calc_inline_size(0);
3507 memmove(inline_data + start, inline_data + start + skip, datal);
3510 write_extent_buffer(path->nodes[0], inline_data,
3511 btrfs_item_ptr_offset(path->nodes[0],
3512 path->slots[0]),
3513 size);
3514 inode_add_bytes(dst, datal);
3516 return 0;
3520 * btrfs_clone() - clone a range from inode file to another
3522 * @src: Inode to clone from
3523 * @inode: Inode to clone to
3524 * @off: Offset within source to start clone from
3525 * @olen: Original length, passed by user, of range to clone
3526 * @olen_aligned: Block-aligned value of olen
3527 * @destoff: Offset within @inode to start clone
3528 * @no_time_update: Whether to update mtime/ctime on the target inode
3530 static int btrfs_clone(struct inode *src, struct inode *inode,
3531 const u64 off, const u64 olen, const u64 olen_aligned,
3532 const u64 destoff, int no_time_update)
3534 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3535 struct btrfs_root *root = BTRFS_I(inode)->root;
3536 struct btrfs_path *path = NULL;
3537 struct extent_buffer *leaf;
3538 struct btrfs_trans_handle *trans;
3539 char *buf = NULL;
3540 struct btrfs_key key;
3541 u32 nritems;
3542 int slot;
3543 int ret;
3544 const u64 len = olen_aligned;
3545 u64 last_dest_end = destoff;
3547 ret = -ENOMEM;
3548 buf = kmalloc(fs_info->nodesize, GFP_KERNEL | __GFP_NOWARN);
3549 if (!buf) {
3550 buf = vmalloc(fs_info->nodesize);
3551 if (!buf)
3552 return ret;
3555 path = btrfs_alloc_path();
3556 if (!path) {
3557 kvfree(buf);
3558 return ret;
3561 path->reada = READA_FORWARD;
3562 /* clone data */
3563 key.objectid = btrfs_ino(BTRFS_I(src));
3564 key.type = BTRFS_EXTENT_DATA_KEY;
3565 key.offset = off;
3567 while (1) {
3568 u64 next_key_min_offset = key.offset + 1;
3571 * note the key will change type as we walk through the
3572 * tree.
3574 path->leave_spinning = 1;
3575 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3576 0, 0);
3577 if (ret < 0)
3578 goto out;
3580 * First search, if no extent item that starts at offset off was
3581 * found but the previous item is an extent item, it's possible
3582 * it might overlap our target range, therefore process it.
3584 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3585 btrfs_item_key_to_cpu(path->nodes[0], &key,
3586 path->slots[0] - 1);
3587 if (key.type == BTRFS_EXTENT_DATA_KEY)
3588 path->slots[0]--;
3591 nritems = btrfs_header_nritems(path->nodes[0]);
3592 process_slot:
3593 if (path->slots[0] >= nritems) {
3594 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3595 if (ret < 0)
3596 goto out;
3597 if (ret > 0)
3598 break;
3599 nritems = btrfs_header_nritems(path->nodes[0]);
3601 leaf = path->nodes[0];
3602 slot = path->slots[0];
3604 btrfs_item_key_to_cpu(leaf, &key, slot);
3605 if (key.type > BTRFS_EXTENT_DATA_KEY ||
3606 key.objectid != btrfs_ino(BTRFS_I(src)))
3607 break;
3609 if (key.type == BTRFS_EXTENT_DATA_KEY) {
3610 struct btrfs_file_extent_item *extent;
3611 int type;
3612 u32 size;
3613 struct btrfs_key new_key;
3614 u64 disko = 0, diskl = 0;
3615 u64 datao = 0, datal = 0;
3616 u8 comp;
3617 u64 drop_start;
3619 extent = btrfs_item_ptr(leaf, slot,
3620 struct btrfs_file_extent_item);
3621 comp = btrfs_file_extent_compression(leaf, extent);
3622 type = btrfs_file_extent_type(leaf, extent);
3623 if (type == BTRFS_FILE_EXTENT_REG ||
3624 type == BTRFS_FILE_EXTENT_PREALLOC) {
3625 disko = btrfs_file_extent_disk_bytenr(leaf,
3626 extent);
3627 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3628 extent);
3629 datao = btrfs_file_extent_offset(leaf, extent);
3630 datal = btrfs_file_extent_num_bytes(leaf,
3631 extent);
3632 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3633 /* take upper bound, may be compressed */
3634 datal = btrfs_file_extent_ram_bytes(leaf,
3635 extent);
3639 * The first search might have left us at an extent
3640 * item that ends before our target range's start, can
3641 * happen if we have holes and NO_HOLES feature enabled.
3643 if (key.offset + datal <= off) {
3644 path->slots[0]++;
3645 goto process_slot;
3646 } else if (key.offset >= off + len) {
3647 break;
3649 next_key_min_offset = key.offset + datal;
3650 size = btrfs_item_size_nr(leaf, slot);
3651 read_extent_buffer(leaf, buf,
3652 btrfs_item_ptr_offset(leaf, slot),
3653 size);
3655 btrfs_release_path(path);
3656 path->leave_spinning = 0;
3658 memcpy(&new_key, &key, sizeof(new_key));
3659 new_key.objectid = btrfs_ino(BTRFS_I(inode));
3660 if (off <= key.offset)
3661 new_key.offset = key.offset + destoff - off;
3662 else
3663 new_key.offset = destoff;
3666 * Deal with a hole that doesn't have an extent item
3667 * that represents it (NO_HOLES feature enabled).
3668 * This hole is either in the middle of the cloning
3669 * range or at the beginning (fully overlaps it or
3670 * partially overlaps it).
3672 if (new_key.offset != last_dest_end)
3673 drop_start = last_dest_end;
3674 else
3675 drop_start = new_key.offset;
3678 * 1 - adjusting old extent (we may have to split it)
3679 * 1 - add new extent
3680 * 1 - inode update
3682 trans = btrfs_start_transaction(root, 3);
3683 if (IS_ERR(trans)) {
3684 ret = PTR_ERR(trans);
3685 goto out;
3688 if (type == BTRFS_FILE_EXTENT_REG ||
3689 type == BTRFS_FILE_EXTENT_PREALLOC) {
3691 * a | --- range to clone ---| b
3692 * | ------------- extent ------------- |
3695 /* subtract range b */
3696 if (key.offset + datal > off + len)
3697 datal = off + len - key.offset;
3699 /* subtract range a */
3700 if (off > key.offset) {
3701 datao += off - key.offset;
3702 datal -= off - key.offset;
3705 ret = btrfs_drop_extents(trans, root, inode,
3706 drop_start,
3707 new_key.offset + datal,
3709 if (ret) {
3710 if (ret != -EOPNOTSUPP)
3711 btrfs_abort_transaction(trans,
3712 ret);
3713 btrfs_end_transaction(trans);
3714 goto out;
3717 ret = btrfs_insert_empty_item(trans, root, path,
3718 &new_key, size);
3719 if (ret) {
3720 btrfs_abort_transaction(trans, ret);
3721 btrfs_end_transaction(trans);
3722 goto out;
3725 leaf = path->nodes[0];
3726 slot = path->slots[0];
3727 write_extent_buffer(leaf, buf,
3728 btrfs_item_ptr_offset(leaf, slot),
3729 size);
3731 extent = btrfs_item_ptr(leaf, slot,
3732 struct btrfs_file_extent_item);
3734 /* disko == 0 means it's a hole */
3735 if (!disko)
3736 datao = 0;
3738 btrfs_set_file_extent_offset(leaf, extent,
3739 datao);
3740 btrfs_set_file_extent_num_bytes(leaf, extent,
3741 datal);
3743 if (disko) {
3744 inode_add_bytes(inode, datal);
3745 ret = btrfs_inc_extent_ref(trans,
3746 fs_info,
3747 disko, diskl, 0,
3748 root->root_key.objectid,
3749 btrfs_ino(BTRFS_I(inode)),
3750 new_key.offset - datao);
3751 if (ret) {
3752 btrfs_abort_transaction(trans,
3753 ret);
3754 btrfs_end_transaction(trans);
3755 goto out;
3759 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3760 u64 skip = 0;
3761 u64 trim = 0;
3763 if (off > key.offset) {
3764 skip = off - key.offset;
3765 new_key.offset += skip;
3768 if (key.offset + datal > off + len)
3769 trim = key.offset + datal - (off + len);
3771 if (comp && (skip || trim)) {
3772 ret = -EINVAL;
3773 btrfs_end_transaction(trans);
3774 goto out;
3776 size -= skip + trim;
3777 datal -= skip + trim;
3779 ret = clone_copy_inline_extent(src, inode,
3780 trans, path,
3781 &new_key,
3782 drop_start,
3783 datal,
3784 skip, size, buf);
3785 if (ret) {
3786 if (ret != -EOPNOTSUPP)
3787 btrfs_abort_transaction(trans,
3788 ret);
3789 btrfs_end_transaction(trans);
3790 goto out;
3792 leaf = path->nodes[0];
3793 slot = path->slots[0];
3796 /* If we have an implicit hole (NO_HOLES feature). */
3797 if (drop_start < new_key.offset)
3798 clone_update_extent_map(inode, trans,
3799 NULL, drop_start,
3800 new_key.offset - drop_start);
3802 clone_update_extent_map(inode, trans, path, 0, 0);
3804 btrfs_mark_buffer_dirty(leaf);
3805 btrfs_release_path(path);
3807 last_dest_end = ALIGN(new_key.offset + datal,
3808 fs_info->sectorsize);
3809 ret = clone_finish_inode_update(trans, inode,
3810 last_dest_end,
3811 destoff, olen,
3812 no_time_update);
3813 if (ret)
3814 goto out;
3815 if (new_key.offset + datal >= destoff + len)
3816 break;
3818 btrfs_release_path(path);
3819 key.offset = next_key_min_offset;
3821 if (fatal_signal_pending(current)) {
3822 ret = -EINTR;
3823 goto out;
3826 ret = 0;
3828 if (last_dest_end < destoff + len) {
3830 * We have an implicit hole (NO_HOLES feature is enabled) that
3831 * fully or partially overlaps our cloning range at its end.
3833 btrfs_release_path(path);
3836 * 1 - remove extent(s)
3837 * 1 - inode update
3839 trans = btrfs_start_transaction(root, 2);
3840 if (IS_ERR(trans)) {
3841 ret = PTR_ERR(trans);
3842 goto out;
3844 ret = btrfs_drop_extents(trans, root, inode,
3845 last_dest_end, destoff + len, 1);
3846 if (ret) {
3847 if (ret != -EOPNOTSUPP)
3848 btrfs_abort_transaction(trans, ret);
3849 btrfs_end_transaction(trans);
3850 goto out;
3852 clone_update_extent_map(inode, trans, NULL, last_dest_end,
3853 destoff + len - last_dest_end);
3854 ret = clone_finish_inode_update(trans, inode, destoff + len,
3855 destoff, olen, no_time_update);
3858 out:
3859 btrfs_free_path(path);
3860 kvfree(buf);
3861 return ret;
3864 static noinline int btrfs_clone_files(struct file *file, struct file *file_src,
3865 u64 off, u64 olen, u64 destoff)
3867 struct inode *inode = file_inode(file);
3868 struct inode *src = file_inode(file_src);
3869 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3870 struct btrfs_root *root = BTRFS_I(inode)->root;
3871 int ret;
3872 u64 len = olen;
3873 u64 bs = fs_info->sb->s_blocksize;
3874 int same_inode = src == inode;
3877 * TODO:
3878 * - split compressed inline extents. annoying: we need to
3879 * decompress into destination's address_space (the file offset
3880 * may change, so source mapping won't do), then recompress (or
3881 * otherwise reinsert) a subrange.
3883 * - split destination inode's inline extents. The inline extents can
3884 * be either compressed or non-compressed.
3887 if (btrfs_root_readonly(root))
3888 return -EROFS;
3890 if (file_src->f_path.mnt != file->f_path.mnt ||
3891 src->i_sb != inode->i_sb)
3892 return -EXDEV;
3894 /* don't make the dst file partly checksummed */
3895 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3896 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3897 return -EINVAL;
3899 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3900 return -EISDIR;
3902 if (!same_inode) {
3903 btrfs_double_inode_lock(src, inode);
3904 } else {
3905 inode_lock(src);
3908 /* determine range to clone */
3909 ret = -EINVAL;
3910 if (off + len > src->i_size || off + len < off)
3911 goto out_unlock;
3912 if (len == 0)
3913 olen = len = src->i_size - off;
3914 /* if we extend to eof, continue to block boundary */
3915 if (off + len == src->i_size)
3916 len = ALIGN(src->i_size, bs) - off;
3918 if (len == 0) {
3919 ret = 0;
3920 goto out_unlock;
3923 /* verify the end result is block aligned */
3924 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
3925 !IS_ALIGNED(destoff, bs))
3926 goto out_unlock;
3928 /* verify if ranges are overlapped within the same file */
3929 if (same_inode) {
3930 if (destoff + len > off && destoff < off + len)
3931 goto out_unlock;
3934 if (destoff > inode->i_size) {
3935 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3936 if (ret)
3937 goto out_unlock;
3941 * Lock the target range too. Right after we replace the file extent
3942 * items in the fs tree (which now point to the cloned data), we might
3943 * have a worker replace them with extent items relative to a write
3944 * operation that was issued before this clone operation (i.e. confront
3945 * with inode.c:btrfs_finish_ordered_io).
3947 if (same_inode) {
3948 u64 lock_start = min_t(u64, off, destoff);
3949 u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
3951 ret = lock_extent_range(src, lock_start, lock_len, true);
3952 } else {
3953 ret = btrfs_double_extent_lock(src, off, inode, destoff, len,
3954 true);
3956 ASSERT(ret == 0);
3957 if (WARN_ON(ret)) {
3958 /* ranges in the io trees already unlocked */
3959 goto out_unlock;
3962 ret = btrfs_clone(src, inode, off, olen, len, destoff, 0);
3964 if (same_inode) {
3965 u64 lock_start = min_t(u64, off, destoff);
3966 u64 lock_end = max_t(u64, off, destoff) + len - 1;
3968 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
3969 } else {
3970 btrfs_double_extent_unlock(src, off, inode, destoff, len);
3973 * Truncate page cache pages so that future reads will see the cloned
3974 * data immediately and not the previous data.
3976 truncate_inode_pages_range(&inode->i_data,
3977 round_down(destoff, PAGE_SIZE),
3978 round_up(destoff + len, PAGE_SIZE) - 1);
3979 out_unlock:
3980 if (!same_inode)
3981 btrfs_double_inode_unlock(src, inode);
3982 else
3983 inode_unlock(src);
3984 return ret;
3987 int btrfs_clone_file_range(struct file *src_file, loff_t off,
3988 struct file *dst_file, loff_t destoff, u64 len)
3990 return btrfs_clone_files(dst_file, src_file, off, len, destoff);
3994 * there are many ways the trans_start and trans_end ioctls can lead
3995 * to deadlocks. They should only be used by applications that
3996 * basically own the machine, and have a very in depth understanding
3997 * of all the possible deadlocks and enospc problems.
3999 static long btrfs_ioctl_trans_start(struct file *file)
4001 struct inode *inode = file_inode(file);
4002 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4003 struct btrfs_root *root = BTRFS_I(inode)->root;
4004 struct btrfs_trans_handle *trans;
4005 int ret;
4007 ret = -EPERM;
4008 if (!capable(CAP_SYS_ADMIN))
4009 goto out;
4011 ret = -EINPROGRESS;
4012 if (file->private_data)
4013 goto out;
4015 ret = -EROFS;
4016 if (btrfs_root_readonly(root))
4017 goto out;
4019 ret = mnt_want_write_file(file);
4020 if (ret)
4021 goto out;
4023 atomic_inc(&fs_info->open_ioctl_trans);
4025 ret = -ENOMEM;
4026 trans = btrfs_start_ioctl_transaction(root);
4027 if (IS_ERR(trans))
4028 goto out_drop;
4030 file->private_data = trans;
4031 return 0;
4033 out_drop:
4034 atomic_dec(&fs_info->open_ioctl_trans);
4035 mnt_drop_write_file(file);
4036 out:
4037 return ret;
4040 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
4042 struct inode *inode = file_inode(file);
4043 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4044 struct btrfs_root *root = BTRFS_I(inode)->root;
4045 struct btrfs_root *new_root;
4046 struct btrfs_dir_item *di;
4047 struct btrfs_trans_handle *trans;
4048 struct btrfs_path *path;
4049 struct btrfs_key location;
4050 struct btrfs_disk_key disk_key;
4051 u64 objectid = 0;
4052 u64 dir_id;
4053 int ret;
4055 if (!capable(CAP_SYS_ADMIN))
4056 return -EPERM;
4058 ret = mnt_want_write_file(file);
4059 if (ret)
4060 return ret;
4062 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
4063 ret = -EFAULT;
4064 goto out;
4067 if (!objectid)
4068 objectid = BTRFS_FS_TREE_OBJECTID;
4070 location.objectid = objectid;
4071 location.type = BTRFS_ROOT_ITEM_KEY;
4072 location.offset = (u64)-1;
4074 new_root = btrfs_read_fs_root_no_name(fs_info, &location);
4075 if (IS_ERR(new_root)) {
4076 ret = PTR_ERR(new_root);
4077 goto out;
4080 path = btrfs_alloc_path();
4081 if (!path) {
4082 ret = -ENOMEM;
4083 goto out;
4085 path->leave_spinning = 1;
4087 trans = btrfs_start_transaction(root, 1);
4088 if (IS_ERR(trans)) {
4089 btrfs_free_path(path);
4090 ret = PTR_ERR(trans);
4091 goto out;
4094 dir_id = btrfs_super_root_dir(fs_info->super_copy);
4095 di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
4096 dir_id, "default", 7, 1);
4097 if (IS_ERR_OR_NULL(di)) {
4098 btrfs_free_path(path);
4099 btrfs_end_transaction(trans);
4100 btrfs_err(fs_info,
4101 "Umm, you don't have the default diritem, this isn't going to work");
4102 ret = -ENOENT;
4103 goto out;
4106 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
4107 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
4108 btrfs_mark_buffer_dirty(path->nodes[0]);
4109 btrfs_free_path(path);
4111 btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
4112 btrfs_end_transaction(trans);
4113 out:
4114 mnt_drop_write_file(file);
4115 return ret;
4118 void btrfs_get_block_group_info(struct list_head *groups_list,
4119 struct btrfs_ioctl_space_info *space)
4121 struct btrfs_block_group_cache *block_group;
4123 space->total_bytes = 0;
4124 space->used_bytes = 0;
4125 space->flags = 0;
4126 list_for_each_entry(block_group, groups_list, list) {
4127 space->flags = block_group->flags;
4128 space->total_bytes += block_group->key.offset;
4129 space->used_bytes +=
4130 btrfs_block_group_used(&block_group->item);
4134 static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
4135 void __user *arg)
4137 struct btrfs_ioctl_space_args space_args;
4138 struct btrfs_ioctl_space_info space;
4139 struct btrfs_ioctl_space_info *dest;
4140 struct btrfs_ioctl_space_info *dest_orig;
4141 struct btrfs_ioctl_space_info __user *user_dest;
4142 struct btrfs_space_info *info;
4143 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
4144 BTRFS_BLOCK_GROUP_SYSTEM,
4145 BTRFS_BLOCK_GROUP_METADATA,
4146 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
4147 int num_types = 4;
4148 int alloc_size;
4149 int ret = 0;
4150 u64 slot_count = 0;
4151 int i, c;
4153 if (copy_from_user(&space_args,
4154 (struct btrfs_ioctl_space_args __user *)arg,
4155 sizeof(space_args)))
4156 return -EFAULT;
4158 for (i = 0; i < num_types; i++) {
4159 struct btrfs_space_info *tmp;
4161 info = NULL;
4162 rcu_read_lock();
4163 list_for_each_entry_rcu(tmp, &fs_info->space_info,
4164 list) {
4165 if (tmp->flags == types[i]) {
4166 info = tmp;
4167 break;
4170 rcu_read_unlock();
4172 if (!info)
4173 continue;
4175 down_read(&info->groups_sem);
4176 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4177 if (!list_empty(&info->block_groups[c]))
4178 slot_count++;
4180 up_read(&info->groups_sem);
4184 * Global block reserve, exported as a space_info
4186 slot_count++;
4188 /* space_slots == 0 means they are asking for a count */
4189 if (space_args.space_slots == 0) {
4190 space_args.total_spaces = slot_count;
4191 goto out;
4194 slot_count = min_t(u64, space_args.space_slots, slot_count);
4196 alloc_size = sizeof(*dest) * slot_count;
4198 /* we generally have at most 6 or so space infos, one for each raid
4199 * level. So, a whole page should be more than enough for everyone
4201 if (alloc_size > PAGE_SIZE)
4202 return -ENOMEM;
4204 space_args.total_spaces = 0;
4205 dest = kmalloc(alloc_size, GFP_KERNEL);
4206 if (!dest)
4207 return -ENOMEM;
4208 dest_orig = dest;
4210 /* now we have a buffer to copy into */
4211 for (i = 0; i < num_types; i++) {
4212 struct btrfs_space_info *tmp;
4214 if (!slot_count)
4215 break;
4217 info = NULL;
4218 rcu_read_lock();
4219 list_for_each_entry_rcu(tmp, &fs_info->space_info,
4220 list) {
4221 if (tmp->flags == types[i]) {
4222 info = tmp;
4223 break;
4226 rcu_read_unlock();
4228 if (!info)
4229 continue;
4230 down_read(&info->groups_sem);
4231 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
4232 if (!list_empty(&info->block_groups[c])) {
4233 btrfs_get_block_group_info(
4234 &info->block_groups[c], &space);
4235 memcpy(dest, &space, sizeof(space));
4236 dest++;
4237 space_args.total_spaces++;
4238 slot_count--;
4240 if (!slot_count)
4241 break;
4243 up_read(&info->groups_sem);
4247 * Add global block reserve
4249 if (slot_count) {
4250 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
4252 spin_lock(&block_rsv->lock);
4253 space.total_bytes = block_rsv->size;
4254 space.used_bytes = block_rsv->size - block_rsv->reserved;
4255 spin_unlock(&block_rsv->lock);
4256 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
4257 memcpy(dest, &space, sizeof(space));
4258 space_args.total_spaces++;
4261 user_dest = (struct btrfs_ioctl_space_info __user *)
4262 (arg + sizeof(struct btrfs_ioctl_space_args));
4264 if (copy_to_user(user_dest, dest_orig, alloc_size))
4265 ret = -EFAULT;
4267 kfree(dest_orig);
4268 out:
4269 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4270 ret = -EFAULT;
4272 return ret;
4276 * there are many ways the trans_start and trans_end ioctls can lead
4277 * to deadlocks. They should only be used by applications that
4278 * basically own the machine, and have a very in depth understanding
4279 * of all the possible deadlocks and enospc problems.
4281 long btrfs_ioctl_trans_end(struct file *file)
4283 struct inode *inode = file_inode(file);
4284 struct btrfs_root *root = BTRFS_I(inode)->root;
4285 struct btrfs_trans_handle *trans;
4287 trans = file->private_data;
4288 if (!trans)
4289 return -EINVAL;
4290 file->private_data = NULL;
4292 btrfs_end_transaction(trans);
4294 atomic_dec(&root->fs_info->open_ioctl_trans);
4296 mnt_drop_write_file(file);
4297 return 0;
4300 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4301 void __user *argp)
4303 struct btrfs_trans_handle *trans;
4304 u64 transid;
4305 int ret;
4307 trans = btrfs_attach_transaction_barrier(root);
4308 if (IS_ERR(trans)) {
4309 if (PTR_ERR(trans) != -ENOENT)
4310 return PTR_ERR(trans);
4312 /* No running transaction, don't bother */
4313 transid = root->fs_info->last_trans_committed;
4314 goto out;
4316 transid = trans->transid;
4317 ret = btrfs_commit_transaction_async(trans, 0);
4318 if (ret) {
4319 btrfs_end_transaction(trans);
4320 return ret;
4322 out:
4323 if (argp)
4324 if (copy_to_user(argp, &transid, sizeof(transid)))
4325 return -EFAULT;
4326 return 0;
4329 static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,
4330 void __user *argp)
4332 u64 transid;
4334 if (argp) {
4335 if (copy_from_user(&transid, argp, sizeof(transid)))
4336 return -EFAULT;
4337 } else {
4338 transid = 0; /* current trans */
4340 return btrfs_wait_for_commit(fs_info, transid);
4343 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4345 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
4346 struct btrfs_ioctl_scrub_args *sa;
4347 int ret;
4349 if (!capable(CAP_SYS_ADMIN))
4350 return -EPERM;
4352 sa = memdup_user(arg, sizeof(*sa));
4353 if (IS_ERR(sa))
4354 return PTR_ERR(sa);
4356 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4357 ret = mnt_want_write_file(file);
4358 if (ret)
4359 goto out;
4362 ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,
4363 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4366 if (copy_to_user(arg, sa, sizeof(*sa)))
4367 ret = -EFAULT;
4369 if (!(sa->flags & BTRFS_SCRUB_READONLY))
4370 mnt_drop_write_file(file);
4371 out:
4372 kfree(sa);
4373 return ret;
4376 static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)
4378 if (!capable(CAP_SYS_ADMIN))
4379 return -EPERM;
4381 return btrfs_scrub_cancel(fs_info);
4384 static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
4385 void __user *arg)
4387 struct btrfs_ioctl_scrub_args *sa;
4388 int ret;
4390 if (!capable(CAP_SYS_ADMIN))
4391 return -EPERM;
4393 sa = memdup_user(arg, sizeof(*sa));
4394 if (IS_ERR(sa))
4395 return PTR_ERR(sa);
4397 ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
4399 if (copy_to_user(arg, sa, sizeof(*sa)))
4400 ret = -EFAULT;
4402 kfree(sa);
4403 return ret;
4406 static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
4407 void __user *arg)
4409 struct btrfs_ioctl_get_dev_stats *sa;
4410 int ret;
4412 sa = memdup_user(arg, sizeof(*sa));
4413 if (IS_ERR(sa))
4414 return PTR_ERR(sa);
4416 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4417 kfree(sa);
4418 return -EPERM;
4421 ret = btrfs_get_dev_stats(fs_info, sa);
4423 if (copy_to_user(arg, sa, sizeof(*sa)))
4424 ret = -EFAULT;
4426 kfree(sa);
4427 return ret;
4430 static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
4431 void __user *arg)
4433 struct btrfs_ioctl_dev_replace_args *p;
4434 int ret;
4436 if (!capable(CAP_SYS_ADMIN))
4437 return -EPERM;
4439 p = memdup_user(arg, sizeof(*p));
4440 if (IS_ERR(p))
4441 return PTR_ERR(p);
4443 switch (p->cmd) {
4444 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4445 if (fs_info->sb->s_flags & MS_RDONLY) {
4446 ret = -EROFS;
4447 goto out;
4449 if (atomic_xchg(
4450 &fs_info->mutually_exclusive_operation_running, 1)) {
4451 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4452 } else {
4453 ret = btrfs_dev_replace_by_ioctl(fs_info, p);
4454 atomic_set(
4455 &fs_info->mutually_exclusive_operation_running, 0);
4457 break;
4458 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4459 btrfs_dev_replace_status(fs_info, p);
4460 ret = 0;
4461 break;
4462 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4463 ret = btrfs_dev_replace_cancel(fs_info, p);
4464 break;
4465 default:
4466 ret = -EINVAL;
4467 break;
4470 if (copy_to_user(arg, p, sizeof(*p)))
4471 ret = -EFAULT;
4472 out:
4473 kfree(p);
4474 return ret;
4477 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4479 int ret = 0;
4480 int i;
4481 u64 rel_ptr;
4482 int size;
4483 struct btrfs_ioctl_ino_path_args *ipa = NULL;
4484 struct inode_fs_paths *ipath = NULL;
4485 struct btrfs_path *path;
4487 if (!capable(CAP_DAC_READ_SEARCH))
4488 return -EPERM;
4490 path = btrfs_alloc_path();
4491 if (!path) {
4492 ret = -ENOMEM;
4493 goto out;
4496 ipa = memdup_user(arg, sizeof(*ipa));
4497 if (IS_ERR(ipa)) {
4498 ret = PTR_ERR(ipa);
4499 ipa = NULL;
4500 goto out;
4503 size = min_t(u32, ipa->size, 4096);
4504 ipath = init_ipath(size, root, path);
4505 if (IS_ERR(ipath)) {
4506 ret = PTR_ERR(ipath);
4507 ipath = NULL;
4508 goto out;
4511 ret = paths_from_inode(ipa->inum, ipath);
4512 if (ret < 0)
4513 goto out;
4515 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4516 rel_ptr = ipath->fspath->val[i] -
4517 (u64)(unsigned long)ipath->fspath->val;
4518 ipath->fspath->val[i] = rel_ptr;
4521 ret = copy_to_user((void *)(unsigned long)ipa->fspath,
4522 (void *)(unsigned long)ipath->fspath, size);
4523 if (ret) {
4524 ret = -EFAULT;
4525 goto out;
4528 out:
4529 btrfs_free_path(path);
4530 free_ipath(ipath);
4531 kfree(ipa);
4533 return ret;
4536 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4538 struct btrfs_data_container *inodes = ctx;
4539 const size_t c = 3 * sizeof(u64);
4541 if (inodes->bytes_left >= c) {
4542 inodes->bytes_left -= c;
4543 inodes->val[inodes->elem_cnt] = inum;
4544 inodes->val[inodes->elem_cnt + 1] = offset;
4545 inodes->val[inodes->elem_cnt + 2] = root;
4546 inodes->elem_cnt += 3;
4547 } else {
4548 inodes->bytes_missing += c - inodes->bytes_left;
4549 inodes->bytes_left = 0;
4550 inodes->elem_missed += 3;
4553 return 0;
4556 static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,
4557 void __user *arg)
4559 int ret = 0;
4560 int size;
4561 struct btrfs_ioctl_logical_ino_args *loi;
4562 struct btrfs_data_container *inodes = NULL;
4563 struct btrfs_path *path = NULL;
4565 if (!capable(CAP_SYS_ADMIN))
4566 return -EPERM;
4568 loi = memdup_user(arg, sizeof(*loi));
4569 if (IS_ERR(loi))
4570 return PTR_ERR(loi);
4572 path = btrfs_alloc_path();
4573 if (!path) {
4574 ret = -ENOMEM;
4575 goto out;
4578 size = min_t(u32, loi->size, SZ_64K);
4579 inodes = init_data_container(size);
4580 if (IS_ERR(inodes)) {
4581 ret = PTR_ERR(inodes);
4582 inodes = NULL;
4583 goto out;
4586 ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
4587 build_ino_list, inodes);
4588 if (ret == -EINVAL)
4589 ret = -ENOENT;
4590 if (ret < 0)
4591 goto out;
4593 ret = copy_to_user((void *)(unsigned long)loi->inodes,
4594 (void *)(unsigned long)inodes, size);
4595 if (ret)
4596 ret = -EFAULT;
4598 out:
4599 btrfs_free_path(path);
4600 vfree(inodes);
4601 kfree(loi);
4603 return ret;
4606 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
4607 struct btrfs_ioctl_balance_args *bargs)
4609 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4611 bargs->flags = bctl->flags;
4613 if (atomic_read(&fs_info->balance_running))
4614 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4615 if (atomic_read(&fs_info->balance_pause_req))
4616 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4617 if (atomic_read(&fs_info->balance_cancel_req))
4618 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4620 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4621 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4622 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4624 if (lock) {
4625 spin_lock(&fs_info->balance_lock);
4626 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4627 spin_unlock(&fs_info->balance_lock);
4628 } else {
4629 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4633 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4635 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4636 struct btrfs_fs_info *fs_info = root->fs_info;
4637 struct btrfs_ioctl_balance_args *bargs;
4638 struct btrfs_balance_control *bctl;
4639 bool need_unlock; /* for mut. excl. ops lock */
4640 int ret;
4642 if (!capable(CAP_SYS_ADMIN))
4643 return -EPERM;
4645 ret = mnt_want_write_file(file);
4646 if (ret)
4647 return ret;
4649 again:
4650 if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
4651 mutex_lock(&fs_info->volume_mutex);
4652 mutex_lock(&fs_info->balance_mutex);
4653 need_unlock = true;
4654 goto locked;
4658 * mut. excl. ops lock is locked. Three possibilities:
4659 * (1) some other op is running
4660 * (2) balance is running
4661 * (3) balance is paused -- special case (think resume)
4663 mutex_lock(&fs_info->balance_mutex);
4664 if (fs_info->balance_ctl) {
4665 /* this is either (2) or (3) */
4666 if (!atomic_read(&fs_info->balance_running)) {
4667 mutex_unlock(&fs_info->balance_mutex);
4668 if (!mutex_trylock(&fs_info->volume_mutex))
4669 goto again;
4670 mutex_lock(&fs_info->balance_mutex);
4672 if (fs_info->balance_ctl &&
4673 !atomic_read(&fs_info->balance_running)) {
4674 /* this is (3) */
4675 need_unlock = false;
4676 goto locked;
4679 mutex_unlock(&fs_info->balance_mutex);
4680 mutex_unlock(&fs_info->volume_mutex);
4681 goto again;
4682 } else {
4683 /* this is (2) */
4684 mutex_unlock(&fs_info->balance_mutex);
4685 ret = -EINPROGRESS;
4686 goto out;
4688 } else {
4689 /* this is (1) */
4690 mutex_unlock(&fs_info->balance_mutex);
4691 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4692 goto out;
4695 locked:
4696 BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4698 if (arg) {
4699 bargs = memdup_user(arg, sizeof(*bargs));
4700 if (IS_ERR(bargs)) {
4701 ret = PTR_ERR(bargs);
4702 goto out_unlock;
4705 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4706 if (!fs_info->balance_ctl) {
4707 ret = -ENOTCONN;
4708 goto out_bargs;
4711 bctl = fs_info->balance_ctl;
4712 spin_lock(&fs_info->balance_lock);
4713 bctl->flags |= BTRFS_BALANCE_RESUME;
4714 spin_unlock(&fs_info->balance_lock);
4716 goto do_balance;
4718 } else {
4719 bargs = NULL;
4722 if (fs_info->balance_ctl) {
4723 ret = -EINPROGRESS;
4724 goto out_bargs;
4727 bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
4728 if (!bctl) {
4729 ret = -ENOMEM;
4730 goto out_bargs;
4733 bctl->fs_info = fs_info;
4734 if (arg) {
4735 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4736 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4737 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4739 bctl->flags = bargs->flags;
4740 } else {
4741 /* balance everything - no filters */
4742 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4745 if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
4746 ret = -EINVAL;
4747 goto out_bctl;
4750 do_balance:
4752 * Ownership of bctl and mutually_exclusive_operation_running
4753 * goes to to btrfs_balance. bctl is freed in __cancel_balance,
4754 * or, if restriper was paused all the way until unmount, in
4755 * free_fs_info. mutually_exclusive_operation_running is
4756 * cleared in __cancel_balance.
4758 need_unlock = false;
4760 ret = btrfs_balance(bctl, bargs);
4761 bctl = NULL;
4763 if (arg) {
4764 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4765 ret = -EFAULT;
4768 out_bctl:
4769 kfree(bctl);
4770 out_bargs:
4771 kfree(bargs);
4772 out_unlock:
4773 mutex_unlock(&fs_info->balance_mutex);
4774 mutex_unlock(&fs_info->volume_mutex);
4775 if (need_unlock)
4776 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
4777 out:
4778 mnt_drop_write_file(file);
4779 return ret;
4782 static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
4784 if (!capable(CAP_SYS_ADMIN))
4785 return -EPERM;
4787 switch (cmd) {
4788 case BTRFS_BALANCE_CTL_PAUSE:
4789 return btrfs_pause_balance(fs_info);
4790 case BTRFS_BALANCE_CTL_CANCEL:
4791 return btrfs_cancel_balance(fs_info);
4794 return -EINVAL;
4797 static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
4798 void __user *arg)
4800 struct btrfs_ioctl_balance_args *bargs;
4801 int ret = 0;
4803 if (!capable(CAP_SYS_ADMIN))
4804 return -EPERM;
4806 mutex_lock(&fs_info->balance_mutex);
4807 if (!fs_info->balance_ctl) {
4808 ret = -ENOTCONN;
4809 goto out;
4812 bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
4813 if (!bargs) {
4814 ret = -ENOMEM;
4815 goto out;
4818 update_ioctl_balance_args(fs_info, 1, bargs);
4820 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4821 ret = -EFAULT;
4823 kfree(bargs);
4824 out:
4825 mutex_unlock(&fs_info->balance_mutex);
4826 return ret;
4829 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4831 struct inode *inode = file_inode(file);
4832 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4833 struct btrfs_ioctl_quota_ctl_args *sa;
4834 struct btrfs_trans_handle *trans = NULL;
4835 int ret;
4836 int err;
4838 if (!capable(CAP_SYS_ADMIN))
4839 return -EPERM;
4841 ret = mnt_want_write_file(file);
4842 if (ret)
4843 return ret;
4845 sa = memdup_user(arg, sizeof(*sa));
4846 if (IS_ERR(sa)) {
4847 ret = PTR_ERR(sa);
4848 goto drop_write;
4851 down_write(&fs_info->subvol_sem);
4852 trans = btrfs_start_transaction(fs_info->tree_root, 2);
4853 if (IS_ERR(trans)) {
4854 ret = PTR_ERR(trans);
4855 goto out;
4858 switch (sa->cmd) {
4859 case BTRFS_QUOTA_CTL_ENABLE:
4860 ret = btrfs_quota_enable(trans, fs_info);
4861 break;
4862 case BTRFS_QUOTA_CTL_DISABLE:
4863 ret = btrfs_quota_disable(trans, fs_info);
4864 break;
4865 default:
4866 ret = -EINVAL;
4867 break;
4870 err = btrfs_commit_transaction(trans);
4871 if (err && !ret)
4872 ret = err;
4873 out:
4874 kfree(sa);
4875 up_write(&fs_info->subvol_sem);
4876 drop_write:
4877 mnt_drop_write_file(file);
4878 return ret;
4881 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4883 struct inode *inode = file_inode(file);
4884 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4885 struct btrfs_root *root = BTRFS_I(inode)->root;
4886 struct btrfs_ioctl_qgroup_assign_args *sa;
4887 struct btrfs_trans_handle *trans;
4888 int ret;
4889 int err;
4891 if (!capable(CAP_SYS_ADMIN))
4892 return -EPERM;
4894 ret = mnt_want_write_file(file);
4895 if (ret)
4896 return ret;
4898 sa = memdup_user(arg, sizeof(*sa));
4899 if (IS_ERR(sa)) {
4900 ret = PTR_ERR(sa);
4901 goto drop_write;
4904 trans = btrfs_join_transaction(root);
4905 if (IS_ERR(trans)) {
4906 ret = PTR_ERR(trans);
4907 goto out;
4910 /* FIXME: check if the IDs really exist */
4911 if (sa->assign) {
4912 ret = btrfs_add_qgroup_relation(trans, fs_info,
4913 sa->src, sa->dst);
4914 } else {
4915 ret = btrfs_del_qgroup_relation(trans, fs_info,
4916 sa->src, sa->dst);
4919 /* update qgroup status and info */
4920 err = btrfs_run_qgroups(trans, fs_info);
4921 if (err < 0)
4922 btrfs_handle_fs_error(fs_info, err,
4923 "failed to update qgroup status and info");
4924 err = btrfs_end_transaction(trans);
4925 if (err && !ret)
4926 ret = err;
4928 out:
4929 kfree(sa);
4930 drop_write:
4931 mnt_drop_write_file(file);
4932 return ret;
4935 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4937 struct inode *inode = file_inode(file);
4938 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4939 struct btrfs_root *root = BTRFS_I(inode)->root;
4940 struct btrfs_ioctl_qgroup_create_args *sa;
4941 struct btrfs_trans_handle *trans;
4942 int ret;
4943 int err;
4945 if (!capable(CAP_SYS_ADMIN))
4946 return -EPERM;
4948 ret = mnt_want_write_file(file);
4949 if (ret)
4950 return ret;
4952 sa = memdup_user(arg, sizeof(*sa));
4953 if (IS_ERR(sa)) {
4954 ret = PTR_ERR(sa);
4955 goto drop_write;
4958 if (!sa->qgroupid) {
4959 ret = -EINVAL;
4960 goto out;
4963 trans = btrfs_join_transaction(root);
4964 if (IS_ERR(trans)) {
4965 ret = PTR_ERR(trans);
4966 goto out;
4969 /* FIXME: check if the IDs really exist */
4970 if (sa->create) {
4971 ret = btrfs_create_qgroup(trans, fs_info, sa->qgroupid);
4972 } else {
4973 ret = btrfs_remove_qgroup(trans, fs_info, sa->qgroupid);
4976 err = btrfs_end_transaction(trans);
4977 if (err && !ret)
4978 ret = err;
4980 out:
4981 kfree(sa);
4982 drop_write:
4983 mnt_drop_write_file(file);
4984 return ret;
4987 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4989 struct inode *inode = file_inode(file);
4990 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4991 struct btrfs_root *root = BTRFS_I(inode)->root;
4992 struct btrfs_ioctl_qgroup_limit_args *sa;
4993 struct btrfs_trans_handle *trans;
4994 int ret;
4995 int err;
4996 u64 qgroupid;
4998 if (!capable(CAP_SYS_ADMIN))
4999 return -EPERM;
5001 ret = mnt_want_write_file(file);
5002 if (ret)
5003 return ret;
5005 sa = memdup_user(arg, sizeof(*sa));
5006 if (IS_ERR(sa)) {
5007 ret = PTR_ERR(sa);
5008 goto drop_write;
5011 trans = btrfs_join_transaction(root);
5012 if (IS_ERR(trans)) {
5013 ret = PTR_ERR(trans);
5014 goto out;
5017 qgroupid = sa->qgroupid;
5018 if (!qgroupid) {
5019 /* take the current subvol as qgroup */
5020 qgroupid = root->root_key.objectid;
5023 /* FIXME: check if the IDs really exist */
5024 ret = btrfs_limit_qgroup(trans, fs_info, qgroupid, &sa->lim);
5026 err = btrfs_end_transaction(trans);
5027 if (err && !ret)
5028 ret = err;
5030 out:
5031 kfree(sa);
5032 drop_write:
5033 mnt_drop_write_file(file);
5034 return ret;
5037 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
5039 struct inode *inode = file_inode(file);
5040 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5041 struct btrfs_ioctl_quota_rescan_args *qsa;
5042 int ret;
5044 if (!capable(CAP_SYS_ADMIN))
5045 return -EPERM;
5047 ret = mnt_want_write_file(file);
5048 if (ret)
5049 return ret;
5051 qsa = memdup_user(arg, sizeof(*qsa));
5052 if (IS_ERR(qsa)) {
5053 ret = PTR_ERR(qsa);
5054 goto drop_write;
5057 if (qsa->flags) {
5058 ret = -EINVAL;
5059 goto out;
5062 ret = btrfs_qgroup_rescan(fs_info);
5064 out:
5065 kfree(qsa);
5066 drop_write:
5067 mnt_drop_write_file(file);
5068 return ret;
5071 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
5073 struct inode *inode = file_inode(file);
5074 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5075 struct btrfs_ioctl_quota_rescan_args *qsa;
5076 int ret = 0;
5078 if (!capable(CAP_SYS_ADMIN))
5079 return -EPERM;
5081 qsa = kzalloc(sizeof(*qsa), GFP_KERNEL);
5082 if (!qsa)
5083 return -ENOMEM;
5085 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
5086 qsa->flags = 1;
5087 qsa->progress = fs_info->qgroup_rescan_progress.objectid;
5090 if (copy_to_user(arg, qsa, sizeof(*qsa)))
5091 ret = -EFAULT;
5093 kfree(qsa);
5094 return ret;
5097 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
5099 struct inode *inode = file_inode(file);
5100 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5102 if (!capable(CAP_SYS_ADMIN))
5103 return -EPERM;
5105 return btrfs_qgroup_wait_for_completion(fs_info, true);
5108 static long _btrfs_ioctl_set_received_subvol(struct file *file,
5109 struct btrfs_ioctl_received_subvol_args *sa)
5111 struct inode *inode = file_inode(file);
5112 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5113 struct btrfs_root *root = BTRFS_I(inode)->root;
5114 struct btrfs_root_item *root_item = &root->root_item;
5115 struct btrfs_trans_handle *trans;
5116 struct timespec ct = current_time(inode);
5117 int ret = 0;
5118 int received_uuid_changed;
5120 if (!inode_owner_or_capable(inode))
5121 return -EPERM;
5123 ret = mnt_want_write_file(file);
5124 if (ret < 0)
5125 return ret;
5127 down_write(&fs_info->subvol_sem);
5129 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
5130 ret = -EINVAL;
5131 goto out;
5134 if (btrfs_root_readonly(root)) {
5135 ret = -EROFS;
5136 goto out;
5140 * 1 - root item
5141 * 2 - uuid items (received uuid + subvol uuid)
5143 trans = btrfs_start_transaction(root, 3);
5144 if (IS_ERR(trans)) {
5145 ret = PTR_ERR(trans);
5146 trans = NULL;
5147 goto out;
5150 sa->rtransid = trans->transid;
5151 sa->rtime.sec = ct.tv_sec;
5152 sa->rtime.nsec = ct.tv_nsec;
5154 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
5155 BTRFS_UUID_SIZE);
5156 if (received_uuid_changed &&
5157 !btrfs_is_empty_uuid(root_item->received_uuid))
5158 btrfs_uuid_tree_rem(trans, fs_info, root_item->received_uuid,
5159 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5160 root->root_key.objectid);
5161 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
5162 btrfs_set_root_stransid(root_item, sa->stransid);
5163 btrfs_set_root_rtransid(root_item, sa->rtransid);
5164 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
5165 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
5166 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
5167 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
5169 ret = btrfs_update_root(trans, fs_info->tree_root,
5170 &root->root_key, &root->root_item);
5171 if (ret < 0) {
5172 btrfs_end_transaction(trans);
5173 goto out;
5175 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
5176 ret = btrfs_uuid_tree_add(trans, fs_info, sa->uuid,
5177 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
5178 root->root_key.objectid);
5179 if (ret < 0 && ret != -EEXIST) {
5180 btrfs_abort_transaction(trans, ret);
5181 goto out;
5184 ret = btrfs_commit_transaction(trans);
5185 if (ret < 0) {
5186 btrfs_abort_transaction(trans, ret);
5187 goto out;
5190 out:
5191 up_write(&fs_info->subvol_sem);
5192 mnt_drop_write_file(file);
5193 return ret;
5196 #ifdef CONFIG_64BIT
5197 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
5198 void __user *arg)
5200 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
5201 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
5202 int ret = 0;
5204 args32 = memdup_user(arg, sizeof(*args32));
5205 if (IS_ERR(args32))
5206 return PTR_ERR(args32);
5208 args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
5209 if (!args64) {
5210 ret = -ENOMEM;
5211 goto out;
5214 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
5215 args64->stransid = args32->stransid;
5216 args64->rtransid = args32->rtransid;
5217 args64->stime.sec = args32->stime.sec;
5218 args64->stime.nsec = args32->stime.nsec;
5219 args64->rtime.sec = args32->rtime.sec;
5220 args64->rtime.nsec = args32->rtime.nsec;
5221 args64->flags = args32->flags;
5223 ret = _btrfs_ioctl_set_received_subvol(file, args64);
5224 if (ret)
5225 goto out;
5227 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
5228 args32->stransid = args64->stransid;
5229 args32->rtransid = args64->rtransid;
5230 args32->stime.sec = args64->stime.sec;
5231 args32->stime.nsec = args64->stime.nsec;
5232 args32->rtime.sec = args64->rtime.sec;
5233 args32->rtime.nsec = args64->rtime.nsec;
5234 args32->flags = args64->flags;
5236 ret = copy_to_user(arg, args32, sizeof(*args32));
5237 if (ret)
5238 ret = -EFAULT;
5240 out:
5241 kfree(args32);
5242 kfree(args64);
5243 return ret;
5245 #endif
5247 static long btrfs_ioctl_set_received_subvol(struct file *file,
5248 void __user *arg)
5250 struct btrfs_ioctl_received_subvol_args *sa = NULL;
5251 int ret = 0;
5253 sa = memdup_user(arg, sizeof(*sa));
5254 if (IS_ERR(sa))
5255 return PTR_ERR(sa);
5257 ret = _btrfs_ioctl_set_received_subvol(file, sa);
5259 if (ret)
5260 goto out;
5262 ret = copy_to_user(arg, sa, sizeof(*sa));
5263 if (ret)
5264 ret = -EFAULT;
5266 out:
5267 kfree(sa);
5268 return ret;
5271 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
5273 struct inode *inode = file_inode(file);
5274 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5275 size_t len;
5276 int ret;
5277 char label[BTRFS_LABEL_SIZE];
5279 spin_lock(&fs_info->super_lock);
5280 memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5281 spin_unlock(&fs_info->super_lock);
5283 len = strnlen(label, BTRFS_LABEL_SIZE);
5285 if (len == BTRFS_LABEL_SIZE) {
5286 btrfs_warn(fs_info,
5287 "label is too long, return the first %zu bytes",
5288 --len);
5291 ret = copy_to_user(arg, label, len);
5293 return ret ? -EFAULT : 0;
5296 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5298 struct inode *inode = file_inode(file);
5299 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5300 struct btrfs_root *root = BTRFS_I(inode)->root;
5301 struct btrfs_super_block *super_block = fs_info->super_copy;
5302 struct btrfs_trans_handle *trans;
5303 char label[BTRFS_LABEL_SIZE];
5304 int ret;
5306 if (!capable(CAP_SYS_ADMIN))
5307 return -EPERM;
5309 if (copy_from_user(label, arg, sizeof(label)))
5310 return -EFAULT;
5312 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5313 btrfs_err(fs_info,
5314 "unable to set label with more than %d bytes",
5315 BTRFS_LABEL_SIZE - 1);
5316 return -EINVAL;
5319 ret = mnt_want_write_file(file);
5320 if (ret)
5321 return ret;
5323 trans = btrfs_start_transaction(root, 0);
5324 if (IS_ERR(trans)) {
5325 ret = PTR_ERR(trans);
5326 goto out_unlock;
5329 spin_lock(&fs_info->super_lock);
5330 strcpy(super_block->label, label);
5331 spin_unlock(&fs_info->super_lock);
5332 ret = btrfs_commit_transaction(trans);
5334 out_unlock:
5335 mnt_drop_write_file(file);
5336 return ret;
5339 #define INIT_FEATURE_FLAGS(suffix) \
5340 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5341 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5342 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5344 int btrfs_ioctl_get_supported_features(void __user *arg)
5346 static const struct btrfs_ioctl_feature_flags features[3] = {
5347 INIT_FEATURE_FLAGS(SUPP),
5348 INIT_FEATURE_FLAGS(SAFE_SET),
5349 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5352 if (copy_to_user(arg, &features, sizeof(features)))
5353 return -EFAULT;
5355 return 0;
5358 static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5360 struct inode *inode = file_inode(file);
5361 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5362 struct btrfs_super_block *super_block = fs_info->super_copy;
5363 struct btrfs_ioctl_feature_flags features;
5365 features.compat_flags = btrfs_super_compat_flags(super_block);
5366 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5367 features.incompat_flags = btrfs_super_incompat_flags(super_block);
5369 if (copy_to_user(arg, &features, sizeof(features)))
5370 return -EFAULT;
5372 return 0;
5375 static int check_feature_bits(struct btrfs_fs_info *fs_info,
5376 enum btrfs_feature_set set,
5377 u64 change_mask, u64 flags, u64 supported_flags,
5378 u64 safe_set, u64 safe_clear)
5380 const char *type = btrfs_feature_set_names[set];
5381 char *names;
5382 u64 disallowed, unsupported;
5383 u64 set_mask = flags & change_mask;
5384 u64 clear_mask = ~flags & change_mask;
5386 unsupported = set_mask & ~supported_flags;
5387 if (unsupported) {
5388 names = btrfs_printable_features(set, unsupported);
5389 if (names) {
5390 btrfs_warn(fs_info,
5391 "this kernel does not support the %s feature bit%s",
5392 names, strchr(names, ',') ? "s" : "");
5393 kfree(names);
5394 } else
5395 btrfs_warn(fs_info,
5396 "this kernel does not support %s bits 0x%llx",
5397 type, unsupported);
5398 return -EOPNOTSUPP;
5401 disallowed = set_mask & ~safe_set;
5402 if (disallowed) {
5403 names = btrfs_printable_features(set, disallowed);
5404 if (names) {
5405 btrfs_warn(fs_info,
5406 "can't set the %s feature bit%s while mounted",
5407 names, strchr(names, ',') ? "s" : "");
5408 kfree(names);
5409 } else
5410 btrfs_warn(fs_info,
5411 "can't set %s bits 0x%llx while mounted",
5412 type, disallowed);
5413 return -EPERM;
5416 disallowed = clear_mask & ~safe_clear;
5417 if (disallowed) {
5418 names = btrfs_printable_features(set, disallowed);
5419 if (names) {
5420 btrfs_warn(fs_info,
5421 "can't clear the %s feature bit%s while mounted",
5422 names, strchr(names, ',') ? "s" : "");
5423 kfree(names);
5424 } else
5425 btrfs_warn(fs_info,
5426 "can't clear %s bits 0x%llx while mounted",
5427 type, disallowed);
5428 return -EPERM;
5431 return 0;
5434 #define check_feature(fs_info, change_mask, flags, mask_base) \
5435 check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags, \
5436 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
5437 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
5438 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5440 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5442 struct inode *inode = file_inode(file);
5443 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5444 struct btrfs_root *root = BTRFS_I(inode)->root;
5445 struct btrfs_super_block *super_block = fs_info->super_copy;
5446 struct btrfs_ioctl_feature_flags flags[2];
5447 struct btrfs_trans_handle *trans;
5448 u64 newflags;
5449 int ret;
5451 if (!capable(CAP_SYS_ADMIN))
5452 return -EPERM;
5454 if (copy_from_user(flags, arg, sizeof(flags)))
5455 return -EFAULT;
5457 /* Nothing to do */
5458 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5459 !flags[0].incompat_flags)
5460 return 0;
5462 ret = check_feature(fs_info, flags[0].compat_flags,
5463 flags[1].compat_flags, COMPAT);
5464 if (ret)
5465 return ret;
5467 ret = check_feature(fs_info, flags[0].compat_ro_flags,
5468 flags[1].compat_ro_flags, COMPAT_RO);
5469 if (ret)
5470 return ret;
5472 ret = check_feature(fs_info, flags[0].incompat_flags,
5473 flags[1].incompat_flags, INCOMPAT);
5474 if (ret)
5475 return ret;
5477 ret = mnt_want_write_file(file);
5478 if (ret)
5479 return ret;
5481 trans = btrfs_start_transaction(root, 0);
5482 if (IS_ERR(trans)) {
5483 ret = PTR_ERR(trans);
5484 goto out_drop_write;
5487 spin_lock(&fs_info->super_lock);
5488 newflags = btrfs_super_compat_flags(super_block);
5489 newflags |= flags[0].compat_flags & flags[1].compat_flags;
5490 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5491 btrfs_set_super_compat_flags(super_block, newflags);
5493 newflags = btrfs_super_compat_ro_flags(super_block);
5494 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5495 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5496 btrfs_set_super_compat_ro_flags(super_block, newflags);
5498 newflags = btrfs_super_incompat_flags(super_block);
5499 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5500 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5501 btrfs_set_super_incompat_flags(super_block, newflags);
5502 spin_unlock(&fs_info->super_lock);
5504 ret = btrfs_commit_transaction(trans);
5505 out_drop_write:
5506 mnt_drop_write_file(file);
5508 return ret;
5511 long btrfs_ioctl(struct file *file, unsigned int
5512 cmd, unsigned long arg)
5514 struct inode *inode = file_inode(file);
5515 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5516 struct btrfs_root *root = BTRFS_I(inode)->root;
5517 void __user *argp = (void __user *)arg;
5519 switch (cmd) {
5520 case FS_IOC_GETFLAGS:
5521 return btrfs_ioctl_getflags(file, argp);
5522 case FS_IOC_SETFLAGS:
5523 return btrfs_ioctl_setflags(file, argp);
5524 case FS_IOC_GETVERSION:
5525 return btrfs_ioctl_getversion(file, argp);
5526 case FITRIM:
5527 return btrfs_ioctl_fitrim(file, argp);
5528 case BTRFS_IOC_SNAP_CREATE:
5529 return btrfs_ioctl_snap_create(file, argp, 0);
5530 case BTRFS_IOC_SNAP_CREATE_V2:
5531 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5532 case BTRFS_IOC_SUBVOL_CREATE:
5533 return btrfs_ioctl_snap_create(file, argp, 1);
5534 case BTRFS_IOC_SUBVOL_CREATE_V2:
5535 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5536 case BTRFS_IOC_SNAP_DESTROY:
5537 return btrfs_ioctl_snap_destroy(file, argp);
5538 case BTRFS_IOC_SUBVOL_GETFLAGS:
5539 return btrfs_ioctl_subvol_getflags(file, argp);
5540 case BTRFS_IOC_SUBVOL_SETFLAGS:
5541 return btrfs_ioctl_subvol_setflags(file, argp);
5542 case BTRFS_IOC_DEFAULT_SUBVOL:
5543 return btrfs_ioctl_default_subvol(file, argp);
5544 case BTRFS_IOC_DEFRAG:
5545 return btrfs_ioctl_defrag(file, NULL);
5546 case BTRFS_IOC_DEFRAG_RANGE:
5547 return btrfs_ioctl_defrag(file, argp);
5548 case BTRFS_IOC_RESIZE:
5549 return btrfs_ioctl_resize(file, argp);
5550 case BTRFS_IOC_ADD_DEV:
5551 return btrfs_ioctl_add_dev(fs_info, argp);
5552 case BTRFS_IOC_RM_DEV:
5553 return btrfs_ioctl_rm_dev(file, argp);
5554 case BTRFS_IOC_RM_DEV_V2:
5555 return btrfs_ioctl_rm_dev_v2(file, argp);
5556 case BTRFS_IOC_FS_INFO:
5557 return btrfs_ioctl_fs_info(fs_info, argp);
5558 case BTRFS_IOC_DEV_INFO:
5559 return btrfs_ioctl_dev_info(fs_info, argp);
5560 case BTRFS_IOC_BALANCE:
5561 return btrfs_ioctl_balance(file, NULL);
5562 case BTRFS_IOC_TRANS_START:
5563 return btrfs_ioctl_trans_start(file);
5564 case BTRFS_IOC_TRANS_END:
5565 return btrfs_ioctl_trans_end(file);
5566 case BTRFS_IOC_TREE_SEARCH:
5567 return btrfs_ioctl_tree_search(file, argp);
5568 case BTRFS_IOC_TREE_SEARCH_V2:
5569 return btrfs_ioctl_tree_search_v2(file, argp);
5570 case BTRFS_IOC_INO_LOOKUP:
5571 return btrfs_ioctl_ino_lookup(file, argp);
5572 case BTRFS_IOC_INO_PATHS:
5573 return btrfs_ioctl_ino_to_path(root, argp);
5574 case BTRFS_IOC_LOGICAL_INO:
5575 return btrfs_ioctl_logical_to_ino(fs_info, argp);
5576 case BTRFS_IOC_SPACE_INFO:
5577 return btrfs_ioctl_space_info(fs_info, argp);
5578 case BTRFS_IOC_SYNC: {
5579 int ret;
5581 ret = btrfs_start_delalloc_roots(fs_info, 0, -1);
5582 if (ret)
5583 return ret;
5584 ret = btrfs_sync_fs(inode->i_sb, 1);
5586 * The transaction thread may want to do more work,
5587 * namely it pokes the cleaner kthread that will start
5588 * processing uncleaned subvols.
5590 wake_up_process(fs_info->transaction_kthread);
5591 return ret;
5593 case BTRFS_IOC_START_SYNC:
5594 return btrfs_ioctl_start_sync(root, argp);
5595 case BTRFS_IOC_WAIT_SYNC:
5596 return btrfs_ioctl_wait_sync(fs_info, argp);
5597 case BTRFS_IOC_SCRUB:
5598 return btrfs_ioctl_scrub(file, argp);
5599 case BTRFS_IOC_SCRUB_CANCEL:
5600 return btrfs_ioctl_scrub_cancel(fs_info);
5601 case BTRFS_IOC_SCRUB_PROGRESS:
5602 return btrfs_ioctl_scrub_progress(fs_info, argp);
5603 case BTRFS_IOC_BALANCE_V2:
5604 return btrfs_ioctl_balance(file, argp);
5605 case BTRFS_IOC_BALANCE_CTL:
5606 return btrfs_ioctl_balance_ctl(fs_info, arg);
5607 case BTRFS_IOC_BALANCE_PROGRESS:
5608 return btrfs_ioctl_balance_progress(fs_info, argp);
5609 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5610 return btrfs_ioctl_set_received_subvol(file, argp);
5611 #ifdef CONFIG_64BIT
5612 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5613 return btrfs_ioctl_set_received_subvol_32(file, argp);
5614 #endif
5615 case BTRFS_IOC_SEND:
5616 return btrfs_ioctl_send(file, argp);
5617 case BTRFS_IOC_GET_DEV_STATS:
5618 return btrfs_ioctl_get_dev_stats(fs_info, argp);
5619 case BTRFS_IOC_QUOTA_CTL:
5620 return btrfs_ioctl_quota_ctl(file, argp);
5621 case BTRFS_IOC_QGROUP_ASSIGN:
5622 return btrfs_ioctl_qgroup_assign(file, argp);
5623 case BTRFS_IOC_QGROUP_CREATE:
5624 return btrfs_ioctl_qgroup_create(file, argp);
5625 case BTRFS_IOC_QGROUP_LIMIT:
5626 return btrfs_ioctl_qgroup_limit(file, argp);
5627 case BTRFS_IOC_QUOTA_RESCAN:
5628 return btrfs_ioctl_quota_rescan(file, argp);
5629 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5630 return btrfs_ioctl_quota_rescan_status(file, argp);
5631 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5632 return btrfs_ioctl_quota_rescan_wait(file, argp);
5633 case BTRFS_IOC_DEV_REPLACE:
5634 return btrfs_ioctl_dev_replace(fs_info, argp);
5635 case BTRFS_IOC_GET_FSLABEL:
5636 return btrfs_ioctl_get_fslabel(file, argp);
5637 case BTRFS_IOC_SET_FSLABEL:
5638 return btrfs_ioctl_set_fslabel(file, argp);
5639 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5640 return btrfs_ioctl_get_supported_features(argp);
5641 case BTRFS_IOC_GET_FEATURES:
5642 return btrfs_ioctl_get_features(file, argp);
5643 case BTRFS_IOC_SET_FEATURES:
5644 return btrfs_ioctl_set_features(file, argp);
5647 return -ENOTTY;
5650 #ifdef CONFIG_COMPAT
5651 long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
5654 * These all access 32-bit values anyway so no further
5655 * handling is necessary.
5657 switch (cmd) {
5658 case FS_IOC32_GETFLAGS:
5659 cmd = FS_IOC_GETFLAGS;
5660 break;
5661 case FS_IOC32_SETFLAGS:
5662 cmd = FS_IOC_SETFLAGS;
5663 break;
5664 case FS_IOC32_GETVERSION:
5665 cmd = FS_IOC_GETVERSION;
5666 break;
5669 return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
5671 #endif