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1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19 #include <linux/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.h>
23 #include <linux/fs.h>
24 #include <linux/fsnotify.h>
25 #include <linux/pagemap.h>
26 #include <linux/highmem.h>
27 #include <linux/time.h>
28 #include <linux/init.h>
29 #include <linux/string.h>
30 #include <linux/backing-dev.h>
31 #include <linux/mount.h>
32 #include <linux/mpage.h>
33 #include <linux/namei.h>
34 #include <linux/swap.h>
35 #include <linux/writeback.h>
36 #include <linux/statfs.h>
37 #include <linux/compat.h>
38 #include <linux/bit_spinlock.h>
39 #include <linux/security.h>
40 #include <linux/xattr.h>
41 #include <linux/vmalloc.h>
42 #include <linux/slab.h>
43 #include <linux/blkdev.h>
44 #include <linux/uuid.h>
45 #include <linux/btrfs.h>
46 #include <linux/uaccess.h>
47 #include "ctree.h"
48 #include "disk-io.h"
49 #include "transaction.h"
50 #include "btrfs_inode.h"
51 #include "print-tree.h"
52 #include "volumes.h"
53 #include "locking.h"
54 #include "inode-map.h"
55 #include "backref.h"
56 #include "rcu-string.h"
57 #include "send.h"
58 #include "dev-replace.h"
59 #include "props.h"
60 #include "sysfs.h"
61 #include "qgroup.h"
62
63 #ifdef CONFIG_64BIT
64 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
65 * structures are incorrect, as the timespec structure from userspace
66 * is 4 bytes too small. We define these alternatives here to teach
67 * the kernel about the 32-bit struct packing.
68 */
69 struct btrfs_ioctl_timespec_32 {
70 __u64 sec;
71 __u32 nsec;
72 } __attribute__ ((__packed__));
73
74 struct btrfs_ioctl_received_subvol_args_32 {
75 char uuid[BTRFS_UUID_SIZE]; /* in */
76 __u64 stransid; /* in */
77 __u64 rtransid; /* out */
78 struct btrfs_ioctl_timespec_32 stime; /* in */
79 struct btrfs_ioctl_timespec_32 rtime; /* out */
80 __u64 flags; /* in */
81 __u64 reserved[16]; /* in */
82 } __attribute__ ((__packed__));
83
84 #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
85 struct btrfs_ioctl_received_subvol_args_32)
86 #endif
87
88
89 static int btrfs_clone(struct inode *src, struct inode *inode,
90 u64 off, u64 olen, u64 olen_aligned, u64 destoff);
91
92 /* Mask out flags that are inappropriate for the given type of inode. */
93 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
94 {
95 if (S_ISDIR(mode))
96 return flags;
97 else if (S_ISREG(mode))
98 return flags & ~FS_DIRSYNC_FL;
99 else
100 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
101 }
102
103 /*
104 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
105 */
106 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
107 {
108 unsigned int iflags = 0;
109
110 if (flags & BTRFS_INODE_SYNC)
111 iflags |= FS_SYNC_FL;
112 if (flags & BTRFS_INODE_IMMUTABLE)
113 iflags |= FS_IMMUTABLE_FL;
114 if (flags & BTRFS_INODE_APPEND)
115 iflags |= FS_APPEND_FL;
116 if (flags & BTRFS_INODE_NODUMP)
117 iflags |= FS_NODUMP_FL;
118 if (flags & BTRFS_INODE_NOATIME)
119 iflags |= FS_NOATIME_FL;
120 if (flags & BTRFS_INODE_DIRSYNC)
121 iflags |= FS_DIRSYNC_FL;
122 if (flags & BTRFS_INODE_NODATACOW)
123 iflags |= FS_NOCOW_FL;
124
125 if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
126 iflags |= FS_COMPR_FL;
127 else if (flags & BTRFS_INODE_NOCOMPRESS)
128 iflags |= FS_NOCOMP_FL;
129
130 return iflags;
131 }
132
133 /*
134 * Update inode->i_flags based on the btrfs internal flags.
135 */
136 void btrfs_update_iflags(struct inode *inode)
137 {
138 struct btrfs_inode *ip = BTRFS_I(inode);
139 unsigned int new_fl = 0;
140
141 if (ip->flags & BTRFS_INODE_SYNC)
142 new_fl |= S_SYNC;
143 if (ip->flags & BTRFS_INODE_IMMUTABLE)
144 new_fl |= S_IMMUTABLE;
145 if (ip->flags & BTRFS_INODE_APPEND)
146 new_fl |= S_APPEND;
147 if (ip->flags & BTRFS_INODE_NOATIME)
148 new_fl |= S_NOATIME;
149 if (ip->flags & BTRFS_INODE_DIRSYNC)
150 new_fl |= S_DIRSYNC;
151
152 set_mask_bits(&inode->i_flags,
153 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
154 new_fl);
155 }
156
157 /*
158 * Inherit flags from the parent inode.
159 *
160 * Currently only the compression flags and the cow flags are inherited.
161 */
162 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
163 {
164 unsigned int flags;
165
166 if (!dir)
167 return;
168
169 flags = BTRFS_I(dir)->flags;
170
171 if (flags & BTRFS_INODE_NOCOMPRESS) {
172 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
173 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
174 } else if (flags & BTRFS_INODE_COMPRESS) {
175 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
176 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
177 }
178
179 if (flags & BTRFS_INODE_NODATACOW) {
180 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
181 if (S_ISREG(inode->i_mode))
182 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
183 }
184
185 btrfs_update_iflags(inode);
186 }
187
188 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
189 {
190 struct btrfs_inode *ip = BTRFS_I(file_inode(file));
191 unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
192
193 if (copy_to_user(arg, &flags, sizeof(flags)))
194 return -EFAULT;
195 return 0;
196 }
197
198 static int check_flags(unsigned int flags)
199 {
200 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
201 FS_NOATIME_FL | FS_NODUMP_FL | \
202 FS_SYNC_FL | FS_DIRSYNC_FL | \
203 FS_NOCOMP_FL | FS_COMPR_FL |
204 FS_NOCOW_FL))
205 return -EOPNOTSUPP;
206
207 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
208 return -EINVAL;
209
210 return 0;
211 }
212
213 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
214 {
215 struct inode *inode = file_inode(file);
216 struct btrfs_inode *ip = BTRFS_I(inode);
217 struct btrfs_root *root = ip->root;
218 struct btrfs_trans_handle *trans;
219 unsigned int flags, oldflags;
220 int ret;
221 u64 ip_oldflags;
222 unsigned int i_oldflags;
223 umode_t mode;
224
225 if (!inode_owner_or_capable(inode))
226 return -EPERM;
227
228 if (btrfs_root_readonly(root))
229 return -EROFS;
230
231 if (copy_from_user(&flags, arg, sizeof(flags)))
232 return -EFAULT;
233
234 ret = check_flags(flags);
235 if (ret)
236 return ret;
237
238 ret = mnt_want_write_file(file);
239 if (ret)
240 return ret;
241
242 mutex_lock(&inode->i_mutex);
243
244 ip_oldflags = ip->flags;
245 i_oldflags = inode->i_flags;
246 mode = inode->i_mode;
247
248 flags = btrfs_mask_flags(inode->i_mode, flags);
249 oldflags = btrfs_flags_to_ioctl(ip->flags);
250 if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
251 if (!capable(CAP_LINUX_IMMUTABLE)) {
252 ret = -EPERM;
253 goto out_unlock;
254 }
255 }
256
257 if (flags & FS_SYNC_FL)
258 ip->flags |= BTRFS_INODE_SYNC;
259 else
260 ip->flags &= ~BTRFS_INODE_SYNC;
261 if (flags & FS_IMMUTABLE_FL)
262 ip->flags |= BTRFS_INODE_IMMUTABLE;
263 else
264 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
265 if (flags & FS_APPEND_FL)
266 ip->flags |= BTRFS_INODE_APPEND;
267 else
268 ip->flags &= ~BTRFS_INODE_APPEND;
269 if (flags & FS_NODUMP_FL)
270 ip->flags |= BTRFS_INODE_NODUMP;
271 else
272 ip->flags &= ~BTRFS_INODE_NODUMP;
273 if (flags & FS_NOATIME_FL)
274 ip->flags |= BTRFS_INODE_NOATIME;
275 else
276 ip->flags &= ~BTRFS_INODE_NOATIME;
277 if (flags & FS_DIRSYNC_FL)
278 ip->flags |= BTRFS_INODE_DIRSYNC;
279 else
280 ip->flags &= ~BTRFS_INODE_DIRSYNC;
281 if (flags & FS_NOCOW_FL) {
282 if (S_ISREG(mode)) {
283 /*
284 * It's safe to turn csums off here, no extents exist.
285 * Otherwise we want the flag to reflect the real COW
286 * status of the file and will not set it.
287 */
288 if (inode->i_size == 0)
289 ip->flags |= BTRFS_INODE_NODATACOW
290 | BTRFS_INODE_NODATASUM;
291 } else {
292 ip->flags |= BTRFS_INODE_NODATACOW;
293 }
294 } else {
295 /*
296 * Revert back under same assuptions as above
297 */
298 if (S_ISREG(mode)) {
299 if (inode->i_size == 0)
300 ip->flags &= ~(BTRFS_INODE_NODATACOW
301 | BTRFS_INODE_NODATASUM);
302 } else {
303 ip->flags &= ~BTRFS_INODE_NODATACOW;
304 }
305 }
306
307 /*
308 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
309 * flag may be changed automatically if compression code won't make
310 * things smaller.
311 */
312 if (flags & FS_NOCOMP_FL) {
313 ip->flags &= ~BTRFS_INODE_COMPRESS;
314 ip->flags |= BTRFS_INODE_NOCOMPRESS;
315
316 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
317 if (ret && ret != -ENODATA)
318 goto out_drop;
319 } else if (flags & FS_COMPR_FL) {
320 const char *comp;
321
322 ip->flags |= BTRFS_INODE_COMPRESS;
323 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
324
325 if (root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
326 comp = "lzo";
327 else
328 comp = "zlib";
329 ret = btrfs_set_prop(inode, "btrfs.compression",
330 comp, strlen(comp), 0);
331 if (ret)
332 goto out_drop;
333
334 } else {
335 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
336 if (ret && ret != -ENODATA)
337 goto out_drop;
338 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
339 }
340
341 trans = btrfs_start_transaction(root, 1);
342 if (IS_ERR(trans)) {
343 ret = PTR_ERR(trans);
344 goto out_drop;
345 }
346
347 btrfs_update_iflags(inode);
348 inode_inc_iversion(inode);
349 inode->i_ctime = CURRENT_TIME;
350 ret = btrfs_update_inode(trans, root, inode);
351
352 btrfs_end_transaction(trans, root);
353 out_drop:
354 if (ret) {
355 ip->flags = ip_oldflags;
356 inode->i_flags = i_oldflags;
357 }
358
359 out_unlock:
360 mutex_unlock(&inode->i_mutex);
361 mnt_drop_write_file(file);
362 return ret;
363 }
364
365 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
366 {
367 struct inode *inode = file_inode(file);
368
369 return put_user(inode->i_generation, arg);
370 }
371
372 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
373 {
374 struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
375 struct btrfs_device *device;
376 struct request_queue *q;
377 struct fstrim_range range;
378 u64 minlen = ULLONG_MAX;
379 u64 num_devices = 0;
380 u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
381 int ret;
382
383 if (!capable(CAP_SYS_ADMIN))
384 return -EPERM;
385
386 rcu_read_lock();
387 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
388 dev_list) {
389 if (!device->bdev)
390 continue;
391 q = bdev_get_queue(device->bdev);
392 if (blk_queue_discard(q)) {
393 num_devices++;
394 minlen = min((u64)q->limits.discard_granularity,
395 minlen);
396 }
397 }
398 rcu_read_unlock();
399
400 if (!num_devices)
401 return -EOPNOTSUPP;
402 if (copy_from_user(&range, arg, sizeof(range)))
403 return -EFAULT;
404 if (range.start > total_bytes ||
405 range.len < fs_info->sb->s_blocksize)
406 return -EINVAL;
407
408 range.len = min(range.len, total_bytes - range.start);
409 range.minlen = max(range.minlen, minlen);
410 ret = btrfs_trim_fs(fs_info->tree_root, &range);
411 if (ret < 0)
412 return ret;
413
414 if (copy_to_user(arg, &range, sizeof(range)))
415 return -EFAULT;
416
417 return 0;
418 }
419
420 int btrfs_is_empty_uuid(u8 *uuid)
421 {
422 int i;
423
424 for (i = 0; i < BTRFS_UUID_SIZE; i++) {
425 if (uuid[i])
426 return 0;
427 }
428 return 1;
429 }
430
431 static noinline int create_subvol(struct inode *dir,
432 struct dentry *dentry,
433 char *name, int namelen,
434 u64 *async_transid,
435 struct btrfs_qgroup_inherit *inherit)
436 {
437 struct btrfs_trans_handle *trans;
438 struct btrfs_key key;
439 struct btrfs_root_item root_item;
440 struct btrfs_inode_item *inode_item;
441 struct extent_buffer *leaf;
442 struct btrfs_root *root = BTRFS_I(dir)->root;
443 struct btrfs_root *new_root;
444 struct btrfs_block_rsv block_rsv;
445 struct timespec cur_time = CURRENT_TIME;
446 struct inode *inode;
447 int ret;
448 int err;
449 u64 objectid;
450 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
451 u64 index = 0;
452 u64 qgroup_reserved;
453 uuid_le new_uuid;
454
455 ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
456 if (ret)
457 return ret;
458
459 /*
460 * Don't create subvolume whose level is not zero. Or qgroup will be
461 * screwed up since it assume subvolme qgroup's level to be 0.
462 */
463 if (btrfs_qgroup_level(objectid))
464 return -ENOSPC;
465
466 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
467 /*
468 * The same as the snapshot creation, please see the comment
469 * of create_snapshot().
470 */
471 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
472 8, &qgroup_reserved, false);
473 if (ret)
474 return ret;
475
476 trans = btrfs_start_transaction(root, 0);
477 if (IS_ERR(trans)) {
478 ret = PTR_ERR(trans);
479 btrfs_subvolume_release_metadata(root, &block_rsv,
480 qgroup_reserved);
481 return ret;
482 }
483 trans->block_rsv = &block_rsv;
484 trans->bytes_reserved = block_rsv.size;
485
486 ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
487 if (ret)
488 goto fail;
489
490 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
491 if (IS_ERR(leaf)) {
492 ret = PTR_ERR(leaf);
493 goto fail;
494 }
495
496 memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
497 btrfs_set_header_bytenr(leaf, leaf->start);
498 btrfs_set_header_generation(leaf, trans->transid);
499 btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
500 btrfs_set_header_owner(leaf, objectid);
501
502 write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(),
503 BTRFS_FSID_SIZE);
504 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
505 btrfs_header_chunk_tree_uuid(leaf),
506 BTRFS_UUID_SIZE);
507 btrfs_mark_buffer_dirty(leaf);
508
509 memset(&root_item, 0, sizeof(root_item));
510
511 inode_item = &root_item.inode;
512 btrfs_set_stack_inode_generation(inode_item, 1);
513 btrfs_set_stack_inode_size(inode_item, 3);
514 btrfs_set_stack_inode_nlink(inode_item, 1);
515 btrfs_set_stack_inode_nbytes(inode_item, root->nodesize);
516 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
517
518 btrfs_set_root_flags(&root_item, 0);
519 btrfs_set_root_limit(&root_item, 0);
520 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
521
522 btrfs_set_root_bytenr(&root_item, leaf->start);
523 btrfs_set_root_generation(&root_item, trans->transid);
524 btrfs_set_root_level(&root_item, 0);
525 btrfs_set_root_refs(&root_item, 1);
526 btrfs_set_root_used(&root_item, leaf->len);
527 btrfs_set_root_last_snapshot(&root_item, 0);
528
529 btrfs_set_root_generation_v2(&root_item,
530 btrfs_root_generation(&root_item));
531 uuid_le_gen(&new_uuid);
532 memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
533 btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
534 btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec);
535 root_item.ctime = root_item.otime;
536 btrfs_set_root_ctransid(&root_item, trans->transid);
537 btrfs_set_root_otransid(&root_item, trans->transid);
538
539 btrfs_tree_unlock(leaf);
540 free_extent_buffer(leaf);
541 leaf = NULL;
542
543 btrfs_set_root_dirid(&root_item, new_dirid);
544
545 key.objectid = objectid;
546 key.offset = 0;
547 key.type = BTRFS_ROOT_ITEM_KEY;
548 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
549 &root_item);
550 if (ret)
551 goto fail;
552
553 key.offset = (u64)-1;
554 new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
555 if (IS_ERR(new_root)) {
556 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
557 ret = PTR_ERR(new_root);
558 goto fail;
559 }
560
561 btrfs_record_root_in_trans(trans, new_root);
562
563 ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
564 if (ret) {
565 /* We potentially lose an unused inode item here */
566 btrfs_abort_transaction(trans, root, ret);
567 goto fail;
568 }
569
570 /*
571 * insert the directory item
572 */
573 ret = btrfs_set_inode_index(dir, &index);
574 if (ret) {
575 btrfs_abort_transaction(trans, root, ret);
576 goto fail;
577 }
578
579 ret = btrfs_insert_dir_item(trans, root,
580 name, namelen, dir, &key,
581 BTRFS_FT_DIR, index);
582 if (ret) {
583 btrfs_abort_transaction(trans, root, ret);
584 goto fail;
585 }
586
587 btrfs_i_size_write(dir, dir->i_size + namelen * 2);
588 ret = btrfs_update_inode(trans, root, dir);
589 BUG_ON(ret);
590
591 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
592 objectid, root->root_key.objectid,
593 btrfs_ino(dir), index, name, namelen);
594 BUG_ON(ret);
595
596 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
597 root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
598 objectid);
599 if (ret)
600 btrfs_abort_transaction(trans, root, ret);
601
602 fail:
603 trans->block_rsv = NULL;
604 trans->bytes_reserved = 0;
605 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
606
607 if (async_transid) {
608 *async_transid = trans->transid;
609 err = btrfs_commit_transaction_async(trans, root, 1);
610 if (err)
611 err = btrfs_commit_transaction(trans, root);
612 } else {
613 err = btrfs_commit_transaction(trans, root);
614 }
615 if (err && !ret)
616 ret = err;
617
618 if (!ret) {
619 inode = btrfs_lookup_dentry(dir, dentry);
620 if (IS_ERR(inode))
621 return PTR_ERR(inode);
622 d_instantiate(dentry, inode);
623 }
624 return ret;
625 }
626
627 static void btrfs_wait_for_no_snapshoting_writes(struct btrfs_root *root)
628 {
629 s64 writers;
630 DEFINE_WAIT(wait);
631
632 do {
633 prepare_to_wait(&root->subv_writers->wait, &wait,
634 TASK_UNINTERRUPTIBLE);
635
636 writers = percpu_counter_sum(&root->subv_writers->counter);
637 if (writers)
638 schedule();
639
640 finish_wait(&root->subv_writers->wait, &wait);
641 } while (writers);
642 }
643
644 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
645 struct dentry *dentry, char *name, int namelen,
646 u64 *async_transid, bool readonly,
647 struct btrfs_qgroup_inherit *inherit)
648 {
649 struct inode *inode;
650 struct btrfs_pending_snapshot *pending_snapshot;
651 struct btrfs_trans_handle *trans;
652 int ret;
653
654 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
655 return -EINVAL;
656
657 atomic_inc(&root->will_be_snapshoted);
658 smp_mb__after_atomic();
659 btrfs_wait_for_no_snapshoting_writes(root);
660
661 ret = btrfs_start_delalloc_inodes(root, 0);
662 if (ret)
663 goto out;
664
665 btrfs_wait_ordered_extents(root, -1);
666
667 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
668 if (!pending_snapshot) {
669 ret = -ENOMEM;
670 goto out;
671 }
672
673 btrfs_init_block_rsv(&pending_snapshot->block_rsv,
674 BTRFS_BLOCK_RSV_TEMP);
675 /*
676 * 1 - parent dir inode
677 * 2 - dir entries
678 * 1 - root item
679 * 2 - root ref/backref
680 * 1 - root of snapshot
681 * 1 - UUID item
682 */
683 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
684 &pending_snapshot->block_rsv, 8,
685 &pending_snapshot->qgroup_reserved,
686 false);
687 if (ret)
688 goto free;
689
690 pending_snapshot->dentry = dentry;
691 pending_snapshot->root = root;
692 pending_snapshot->readonly = readonly;
693 pending_snapshot->dir = dir;
694 pending_snapshot->inherit = inherit;
695
696 trans = btrfs_start_transaction(root, 0);
697 if (IS_ERR(trans)) {
698 ret = PTR_ERR(trans);
699 goto fail;
700 }
701
702 spin_lock(&root->fs_info->trans_lock);
703 list_add(&pending_snapshot->list,
704 &trans->transaction->pending_snapshots);
705 spin_unlock(&root->fs_info->trans_lock);
706 if (async_transid) {
707 *async_transid = trans->transid;
708 ret = btrfs_commit_transaction_async(trans,
709 root->fs_info->extent_root, 1);
710 if (ret)
711 ret = btrfs_commit_transaction(trans, root);
712 } else {
713 ret = btrfs_commit_transaction(trans,
714 root->fs_info->extent_root);
715 }
716 if (ret)
717 goto fail;
718
719 ret = pending_snapshot->error;
720 if (ret)
721 goto fail;
722
723 ret = btrfs_orphan_cleanup(pending_snapshot->snap);
724 if (ret)
725 goto fail;
726
727 inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
728 if (IS_ERR(inode)) {
729 ret = PTR_ERR(inode);
730 goto fail;
731 }
732
733 d_instantiate(dentry, inode);
734 ret = 0;
735 fail:
736 btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
737 &pending_snapshot->block_rsv,
738 pending_snapshot->qgroup_reserved);
739 free:
740 kfree(pending_snapshot);
741 out:
742 if (atomic_dec_and_test(&root->will_be_snapshoted))
743 wake_up_atomic_t(&root->will_be_snapshoted);
744 return ret;
745 }
746
747 /* copy of may_delete in fs/namei.c()
748 * Check whether we can remove a link victim from directory dir, check
749 * whether the type of victim is right.
750 * 1. We can't do it if dir is read-only (done in permission())
751 * 2. We should have write and exec permissions on dir
752 * 3. We can't remove anything from append-only dir
753 * 4. We can't do anything with immutable dir (done in permission())
754 * 5. If the sticky bit on dir is set we should either
755 * a. be owner of dir, or
756 * b. be owner of victim, or
757 * c. have CAP_FOWNER capability
758 * 6. If the victim is append-only or immutable we can't do antyhing with
759 * links pointing to it.
760 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
761 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
762 * 9. We can't remove a root or mountpoint.
763 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
764 * nfs_async_unlink().
765 */
766
767 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
768 {
769 int error;
770
771 if (d_really_is_negative(victim))
772 return -ENOENT;
773
774 BUG_ON(d_inode(victim->d_parent) != dir);
775 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
776
777 error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
778 if (error)
779 return error;
780 if (IS_APPEND(dir))
781 return -EPERM;
782 if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
783 IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
784 return -EPERM;
785 if (isdir) {
786 if (!d_is_dir(victim))
787 return -ENOTDIR;
788 if (IS_ROOT(victim))
789 return -EBUSY;
790 } else if (d_is_dir(victim))
791 return -EISDIR;
792 if (IS_DEADDIR(dir))
793 return -ENOENT;
794 if (victim->d_flags & DCACHE_NFSFS_RENAMED)
795 return -EBUSY;
796 return 0;
797 }
798
799 /* copy of may_create in fs/namei.c() */
800 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
801 {
802 if (d_really_is_positive(child))
803 return -EEXIST;
804 if (IS_DEADDIR(dir))
805 return -ENOENT;
806 return inode_permission(dir, MAY_WRITE | MAY_EXEC);
807 }
808
809 /*
810 * Create a new subvolume below @parent. This is largely modeled after
811 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
812 * inside this filesystem so it's quite a bit simpler.
813 */
814 static noinline int btrfs_mksubvol(struct path *parent,
815 char *name, int namelen,
816 struct btrfs_root *snap_src,
817 u64 *async_transid, bool readonly,
818 struct btrfs_qgroup_inherit *inherit)
819 {
820 struct inode *dir = d_inode(parent->dentry);
821 struct dentry *dentry;
822 int error;
823
824 error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
825 if (error == -EINTR)
826 return error;
827
828 dentry = lookup_one_len(name, parent->dentry, namelen);
829 error = PTR_ERR(dentry);
830 if (IS_ERR(dentry))
831 goto out_unlock;
832
833 error = -EEXIST;
834 if (d_really_is_positive(dentry))
835 goto out_dput;
836
837 error = btrfs_may_create(dir, dentry);
838 if (error)
839 goto out_dput;
840
841 /*
842 * even if this name doesn't exist, we may get hash collisions.
843 * check for them now when we can safely fail
844 */
845 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
846 dir->i_ino, name,
847 namelen);
848 if (error)
849 goto out_dput;
850
851 down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
852
853 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
854 goto out_up_read;
855
856 if (snap_src) {
857 error = create_snapshot(snap_src, dir, dentry, name, namelen,
858 async_transid, readonly, inherit);
859 } else {
860 error = create_subvol(dir, dentry, name, namelen,
861 async_transid, inherit);
862 }
863 if (!error)
864 fsnotify_mkdir(dir, dentry);
865 out_up_read:
866 up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
867 out_dput:
868 dput(dentry);
869 out_unlock:
870 mutex_unlock(&dir->i_mutex);
871 return error;
872 }
873
874 /*
875 * When we're defragging a range, we don't want to kick it off again
876 * if it is really just waiting for delalloc to send it down.
877 * If we find a nice big extent or delalloc range for the bytes in the
878 * file you want to defrag, we return 0 to let you know to skip this
879 * part of the file
880 */
881 static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
882 {
883 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
884 struct extent_map *em = NULL;
885 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
886 u64 end;
887
888 read_lock(&em_tree->lock);
889 em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
890 read_unlock(&em_tree->lock);
891
892 if (em) {
893 end = extent_map_end(em);
894 free_extent_map(em);
895 if (end - offset > thresh)
896 return 0;
897 }
898 /* if we already have a nice delalloc here, just stop */
899 thresh /= 2;
900 end = count_range_bits(io_tree, &offset, offset + thresh,
901 thresh, EXTENT_DELALLOC, 1);
902 if (end >= thresh)
903 return 0;
904 return 1;
905 }
906
907 /*
908 * helper function to walk through a file and find extents
909 * newer than a specific transid, and smaller than thresh.
910 *
911 * This is used by the defragging code to find new and small
912 * extents
913 */
914 static int find_new_extents(struct btrfs_root *root,
915 struct inode *inode, u64 newer_than,
916 u64 *off, u32 thresh)
917 {
918 struct btrfs_path *path;
919 struct btrfs_key min_key;
920 struct extent_buffer *leaf;
921 struct btrfs_file_extent_item *extent;
922 int type;
923 int ret;
924 u64 ino = btrfs_ino(inode);
925
926 path = btrfs_alloc_path();
927 if (!path)
928 return -ENOMEM;
929
930 min_key.objectid = ino;
931 min_key.type = BTRFS_EXTENT_DATA_KEY;
932 min_key.offset = *off;
933
934 while (1) {
935 ret = btrfs_search_forward(root, &min_key, path, newer_than);
936 if (ret != 0)
937 goto none;
938 process_slot:
939 if (min_key.objectid != ino)
940 goto none;
941 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
942 goto none;
943
944 leaf = path->nodes[0];
945 extent = btrfs_item_ptr(leaf, path->slots[0],
946 struct btrfs_file_extent_item);
947
948 type = btrfs_file_extent_type(leaf, extent);
949 if (type == BTRFS_FILE_EXTENT_REG &&
950 btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
951 check_defrag_in_cache(inode, min_key.offset, thresh)) {
952 *off = min_key.offset;
953 btrfs_free_path(path);
954 return 0;
955 }
956
957 path->slots[0]++;
958 if (path->slots[0] < btrfs_header_nritems(leaf)) {
959 btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
960 goto process_slot;
961 }
962
963 if (min_key.offset == (u64)-1)
964 goto none;
965
966 min_key.offset++;
967 btrfs_release_path(path);
968 }
969 none:
970 btrfs_free_path(path);
971 return -ENOENT;
972 }
973
974 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
975 {
976 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
977 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
978 struct extent_map *em;
979 u64 len = PAGE_CACHE_SIZE;
980
981 /*
982 * hopefully we have this extent in the tree already, try without
983 * the full extent lock
984 */
985 read_lock(&em_tree->lock);
986 em = lookup_extent_mapping(em_tree, start, len);
987 read_unlock(&em_tree->lock);
988
989 if (!em) {
990 struct extent_state *cached = NULL;
991 u64 end = start + len - 1;
992
993 /* get the big lock and read metadata off disk */
994 lock_extent_bits(io_tree, start, end, 0, &cached);
995 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
996 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
997
998 if (IS_ERR(em))
999 return NULL;
1000 }
1001
1002 return em;
1003 }
1004
1005 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1006 {
1007 struct extent_map *next;
1008 bool ret = true;
1009
1010 /* this is the last extent */
1011 if (em->start + em->len >= i_size_read(inode))
1012 return false;
1013
1014 next = defrag_lookup_extent(inode, em->start + em->len);
1015 if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1016 ret = false;
1017 else if ((em->block_start + em->block_len == next->block_start) &&
1018 (em->block_len > 128 * 1024 && next->block_len > 128 * 1024))
1019 ret = false;
1020
1021 free_extent_map(next);
1022 return ret;
1023 }
1024
1025 static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1026 u64 *last_len, u64 *skip, u64 *defrag_end,
1027 int compress)
1028 {
1029 struct extent_map *em;
1030 int ret = 1;
1031 bool next_mergeable = true;
1032
1033 /*
1034 * make sure that once we start defragging an extent, we keep on
1035 * defragging it
1036 */
1037 if (start < *defrag_end)
1038 return 1;
1039
1040 *skip = 0;
1041
1042 em = defrag_lookup_extent(inode, start);
1043 if (!em)
1044 return 0;
1045
1046 /* this will cover holes, and inline extents */
1047 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1048 ret = 0;
1049 goto out;
1050 }
1051
1052 next_mergeable = defrag_check_next_extent(inode, em);
1053 /*
1054 * we hit a real extent, if it is big or the next extent is not a
1055 * real extent, don't bother defragging it
1056 */
1057 if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1058 (em->len >= thresh || !next_mergeable))
1059 ret = 0;
1060 out:
1061 /*
1062 * last_len ends up being a counter of how many bytes we've defragged.
1063 * every time we choose not to defrag an extent, we reset *last_len
1064 * so that the next tiny extent will force a defrag.
1065 *
1066 * The end result of this is that tiny extents before a single big
1067 * extent will force at least part of that big extent to be defragged.
1068 */
1069 if (ret) {
1070 *defrag_end = extent_map_end(em);
1071 } else {
1072 *last_len = 0;
1073 *skip = extent_map_end(em);
1074 *defrag_end = 0;
1075 }
1076
1077 free_extent_map(em);
1078 return ret;
1079 }
1080
1081 /*
1082 * it doesn't do much good to defrag one or two pages
1083 * at a time. This pulls in a nice chunk of pages
1084 * to COW and defrag.
1085 *
1086 * It also makes sure the delalloc code has enough
1087 * dirty data to avoid making new small extents as part
1088 * of the defrag
1089 *
1090 * It's a good idea to start RA on this range
1091 * before calling this.
1092 */
1093 static int cluster_pages_for_defrag(struct inode *inode,
1094 struct page **pages,
1095 unsigned long start_index,
1096 unsigned long num_pages)
1097 {
1098 unsigned long file_end;
1099 u64 isize = i_size_read(inode);
1100 u64 page_start;
1101 u64 page_end;
1102 u64 page_cnt;
1103 int ret;
1104 int i;
1105 int i_done;
1106 struct btrfs_ordered_extent *ordered;
1107 struct extent_state *cached_state = NULL;
1108 struct extent_io_tree *tree;
1109 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1110
1111 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1112 if (!isize || start_index > file_end)
1113 return 0;
1114
1115 page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1116
1117 ret = btrfs_delalloc_reserve_space(inode,
1118 page_cnt << PAGE_CACHE_SHIFT);
1119 if (ret)
1120 return ret;
1121 i_done = 0;
1122 tree = &BTRFS_I(inode)->io_tree;
1123
1124 /* step one, lock all the pages */
1125 for (i = 0; i < page_cnt; i++) {
1126 struct page *page;
1127 again:
1128 page = find_or_create_page(inode->i_mapping,
1129 start_index + i, mask);
1130 if (!page)
1131 break;
1132
1133 page_start = page_offset(page);
1134 page_end = page_start + PAGE_CACHE_SIZE - 1;
1135 while (1) {
1136 lock_extent_bits(tree, page_start, page_end,
1137 0, &cached_state);
1138 ordered = btrfs_lookup_ordered_extent(inode,
1139 page_start);
1140 unlock_extent_cached(tree, page_start, page_end,
1141 &cached_state, GFP_NOFS);
1142 if (!ordered)
1143 break;
1144
1145 unlock_page(page);
1146 btrfs_start_ordered_extent(inode, ordered, 1);
1147 btrfs_put_ordered_extent(ordered);
1148 lock_page(page);
1149 /*
1150 * we unlocked the page above, so we need check if
1151 * it was released or not.
1152 */
1153 if (page->mapping != inode->i_mapping) {
1154 unlock_page(page);
1155 page_cache_release(page);
1156 goto again;
1157 }
1158 }
1159
1160 if (!PageUptodate(page)) {
1161 btrfs_readpage(NULL, page);
1162 lock_page(page);
1163 if (!PageUptodate(page)) {
1164 unlock_page(page);
1165 page_cache_release(page);
1166 ret = -EIO;
1167 break;
1168 }
1169 }
1170
1171 if (page->mapping != inode->i_mapping) {
1172 unlock_page(page);
1173 page_cache_release(page);
1174 goto again;
1175 }
1176
1177 pages[i] = page;
1178 i_done++;
1179 }
1180 if (!i_done || ret)
1181 goto out;
1182
1183 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1184 goto out;
1185
1186 /*
1187 * so now we have a nice long stream of locked
1188 * and up to date pages, lets wait on them
1189 */
1190 for (i = 0; i < i_done; i++)
1191 wait_on_page_writeback(pages[i]);
1192
1193 page_start = page_offset(pages[0]);
1194 page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1195
1196 lock_extent_bits(&BTRFS_I(inode)->io_tree,
1197 page_start, page_end - 1, 0, &cached_state);
1198 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1199 page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1200 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1201 &cached_state, GFP_NOFS);
1202
1203 if (i_done != page_cnt) {
1204 spin_lock(&BTRFS_I(inode)->lock);
1205 BTRFS_I(inode)->outstanding_extents++;
1206 spin_unlock(&BTRFS_I(inode)->lock);
1207 btrfs_delalloc_release_space(inode,
1208 (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1209 }
1210
1211
1212 set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1213 &cached_state, GFP_NOFS);
1214
1215 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1216 page_start, page_end - 1, &cached_state,
1217 GFP_NOFS);
1218
1219 for (i = 0; i < i_done; i++) {
1220 clear_page_dirty_for_io(pages[i]);
1221 ClearPageChecked(pages[i]);
1222 set_page_extent_mapped(pages[i]);
1223 set_page_dirty(pages[i]);
1224 unlock_page(pages[i]);
1225 page_cache_release(pages[i]);
1226 }
1227 return i_done;
1228 out:
1229 for (i = 0; i < i_done; i++) {
1230 unlock_page(pages[i]);
1231 page_cache_release(pages[i]);
1232 }
1233 btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1234 return ret;
1235
1236 }
1237
1238 int btrfs_defrag_file(struct inode *inode, struct file *file,
1239 struct btrfs_ioctl_defrag_range_args *range,
1240 u64 newer_than, unsigned long max_to_defrag)
1241 {
1242 struct btrfs_root *root = BTRFS_I(inode)->root;
1243 struct file_ra_state *ra = NULL;
1244 unsigned long last_index;
1245 u64 isize = i_size_read(inode);
1246 u64 last_len = 0;
1247 u64 skip = 0;
1248 u64 defrag_end = 0;
1249 u64 newer_off = range->start;
1250 unsigned long i;
1251 unsigned long ra_index = 0;
1252 int ret;
1253 int defrag_count = 0;
1254 int compress_type = BTRFS_COMPRESS_ZLIB;
1255 u32 extent_thresh = range->extent_thresh;
1256 unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1257 unsigned long cluster = max_cluster;
1258 u64 new_align = ~((u64)128 * 1024 - 1);
1259 struct page **pages = NULL;
1260
1261 if (isize == 0)
1262 return 0;
1263
1264 if (range->start >= isize)
1265 return -EINVAL;
1266
1267 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1268 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1269 return -EINVAL;
1270 if (range->compress_type)
1271 compress_type = range->compress_type;
1272 }
1273
1274 if (extent_thresh == 0)
1275 extent_thresh = 256 * 1024;
1276
1277 /*
1278 * if we were not given a file, allocate a readahead
1279 * context
1280 */
1281 if (!file) {
1282 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1283 if (!ra)
1284 return -ENOMEM;
1285 file_ra_state_init(ra, inode->i_mapping);
1286 } else {
1287 ra = &file->f_ra;
1288 }
1289
1290 pages = kmalloc_array(max_cluster, sizeof(struct page *),
1291 GFP_NOFS);
1292 if (!pages) {
1293 ret = -ENOMEM;
1294 goto out_ra;
1295 }
1296
1297 /* find the last page to defrag */
1298 if (range->start + range->len > range->start) {
1299 last_index = min_t(u64, isize - 1,
1300 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1301 } else {
1302 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1303 }
1304
1305 if (newer_than) {
1306 ret = find_new_extents(root, inode, newer_than,
1307 &newer_off, 64 * 1024);
1308 if (!ret) {
1309 range->start = newer_off;
1310 /*
1311 * we always align our defrag to help keep
1312 * the extents in the file evenly spaced
1313 */
1314 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1315 } else
1316 goto out_ra;
1317 } else {
1318 i = range->start >> PAGE_CACHE_SHIFT;
1319 }
1320 if (!max_to_defrag)
1321 max_to_defrag = last_index + 1;
1322
1323 /*
1324 * make writeback starts from i, so the defrag range can be
1325 * written sequentially.
1326 */
1327 if (i < inode->i_mapping->writeback_index)
1328 inode->i_mapping->writeback_index = i;
1329
1330 while (i <= last_index && defrag_count < max_to_defrag &&
1331 (i < DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE))) {
1332 /*
1333 * make sure we stop running if someone unmounts
1334 * the FS
1335 */
1336 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1337 break;
1338
1339 if (btrfs_defrag_cancelled(root->fs_info)) {
1340 printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n");
1341 ret = -EAGAIN;
1342 break;
1343 }
1344
1345 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1346 extent_thresh, &last_len, &skip,
1347 &defrag_end, range->flags &
1348 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1349 unsigned long next;
1350 /*
1351 * the should_defrag function tells us how much to skip
1352 * bump our counter by the suggested amount
1353 */
1354 next = DIV_ROUND_UP(skip, PAGE_CACHE_SIZE);
1355 i = max(i + 1, next);
1356 continue;
1357 }
1358
1359 if (!newer_than) {
1360 cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1361 PAGE_CACHE_SHIFT) - i;
1362 cluster = min(cluster, max_cluster);
1363 } else {
1364 cluster = max_cluster;
1365 }
1366
1367 if (i + cluster > ra_index) {
1368 ra_index = max(i, ra_index);
1369 btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1370 cluster);
1371 ra_index += max_cluster;
1372 }
1373
1374 mutex_lock(&inode->i_mutex);
1375 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1376 BTRFS_I(inode)->force_compress = compress_type;
1377 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1378 if (ret < 0) {
1379 mutex_unlock(&inode->i_mutex);
1380 goto out_ra;
1381 }
1382
1383 defrag_count += ret;
1384 balance_dirty_pages_ratelimited(inode->i_mapping);
1385 mutex_unlock(&inode->i_mutex);
1386
1387 if (newer_than) {
1388 if (newer_off == (u64)-1)
1389 break;
1390
1391 if (ret > 0)
1392 i += ret;
1393
1394 newer_off = max(newer_off + 1,
1395 (u64)i << PAGE_CACHE_SHIFT);
1396
1397 ret = find_new_extents(root, inode,
1398 newer_than, &newer_off,
1399 64 * 1024);
1400 if (!ret) {
1401 range->start = newer_off;
1402 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1403 } else {
1404 break;
1405 }
1406 } else {
1407 if (ret > 0) {
1408 i += ret;
1409 last_len += ret << PAGE_CACHE_SHIFT;
1410 } else {
1411 i++;
1412 last_len = 0;
1413 }
1414 }
1415 }
1416
1417 if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1418 filemap_flush(inode->i_mapping);
1419 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1420 &BTRFS_I(inode)->runtime_flags))
1421 filemap_flush(inode->i_mapping);
1422 }
1423
1424 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1425 /* the filemap_flush will queue IO into the worker threads, but
1426 * we have to make sure the IO is actually started and that
1427 * ordered extents get created before we return
1428 */
1429 atomic_inc(&root->fs_info->async_submit_draining);
1430 while (atomic_read(&root->fs_info->nr_async_submits) ||
1431 atomic_read(&root->fs_info->async_delalloc_pages)) {
1432 wait_event(root->fs_info->async_submit_wait,
1433 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1434 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1435 }
1436 atomic_dec(&root->fs_info->async_submit_draining);
1437 }
1438
1439 if (range->compress_type == BTRFS_COMPRESS_LZO) {
1440 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1441 }
1442
1443 ret = defrag_count;
1444
1445 out_ra:
1446 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1447 mutex_lock(&inode->i_mutex);
1448 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1449 mutex_unlock(&inode->i_mutex);
1450 }
1451 if (!file)
1452 kfree(ra);
1453 kfree(pages);
1454 return ret;
1455 }
1456
1457 static noinline int btrfs_ioctl_resize(struct file *file,
1458 void __user *arg)
1459 {
1460 u64 new_size;
1461 u64 old_size;
1462 u64 devid = 1;
1463 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
1464 struct btrfs_ioctl_vol_args *vol_args;
1465 struct btrfs_trans_handle *trans;
1466 struct btrfs_device *device = NULL;
1467 char *sizestr;
1468 char *retptr;
1469 char *devstr = NULL;
1470 int ret = 0;
1471 int mod = 0;
1472
1473 if (!capable(CAP_SYS_ADMIN))
1474 return -EPERM;
1475
1476 ret = mnt_want_write_file(file);
1477 if (ret)
1478 return ret;
1479
1480 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1481 1)) {
1482 mnt_drop_write_file(file);
1483 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1484 }
1485
1486 mutex_lock(&root->fs_info->volume_mutex);
1487 vol_args = memdup_user(arg, sizeof(*vol_args));
1488 if (IS_ERR(vol_args)) {
1489 ret = PTR_ERR(vol_args);
1490 goto out;
1491 }
1492
1493 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1494
1495 sizestr = vol_args->name;
1496 devstr = strchr(sizestr, ':');
1497 if (devstr) {
1498 sizestr = devstr + 1;
1499 *devstr = '\0';
1500 devstr = vol_args->name;
1501 ret = kstrtoull(devstr, 10, &devid);
1502 if (ret)
1503 goto out_free;
1504 if (!devid) {
1505 ret = -EINVAL;
1506 goto out_free;
1507 }
1508 btrfs_info(root->fs_info, "resizing devid %llu", devid);
1509 }
1510
1511 device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1512 if (!device) {
1513 btrfs_info(root->fs_info, "resizer unable to find device %llu",
1514 devid);
1515 ret = -ENODEV;
1516 goto out_free;
1517 }
1518
1519 if (!device->writeable) {
1520 btrfs_info(root->fs_info,
1521 "resizer unable to apply on readonly device %llu",
1522 devid);
1523 ret = -EPERM;
1524 goto out_free;
1525 }
1526
1527 if (!strcmp(sizestr, "max"))
1528 new_size = device->bdev->bd_inode->i_size;
1529 else {
1530 if (sizestr[0] == '-') {
1531 mod = -1;
1532 sizestr++;
1533 } else if (sizestr[0] == '+') {
1534 mod = 1;
1535 sizestr++;
1536 }
1537 new_size = memparse(sizestr, &retptr);
1538 if (*retptr != '\0' || new_size == 0) {
1539 ret = -EINVAL;
1540 goto out_free;
1541 }
1542 }
1543
1544 if (device->is_tgtdev_for_dev_replace) {
1545 ret = -EPERM;
1546 goto out_free;
1547 }
1548
1549 old_size = btrfs_device_get_total_bytes(device);
1550
1551 if (mod < 0) {
1552 if (new_size > old_size) {
1553 ret = -EINVAL;
1554 goto out_free;
1555 }
1556 new_size = old_size - new_size;
1557 } else if (mod > 0) {
1558 if (new_size > ULLONG_MAX - old_size) {
1559 ret = -ERANGE;
1560 goto out_free;
1561 }
1562 new_size = old_size + new_size;
1563 }
1564
1565 if (new_size < 256 * 1024 * 1024) {
1566 ret = -EINVAL;
1567 goto out_free;
1568 }
1569 if (new_size > device->bdev->bd_inode->i_size) {
1570 ret = -EFBIG;
1571 goto out_free;
1572 }
1573
1574 new_size = div_u64(new_size, root->sectorsize);
1575 new_size *= root->sectorsize;
1576
1577 printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n",
1578 rcu_str_deref(device->name), new_size);
1579
1580 if (new_size > old_size) {
1581 trans = btrfs_start_transaction(root, 0);
1582 if (IS_ERR(trans)) {
1583 ret = PTR_ERR(trans);
1584 goto out_free;
1585 }
1586 ret = btrfs_grow_device(trans, device, new_size);
1587 btrfs_commit_transaction(trans, root);
1588 } else if (new_size < old_size) {
1589 ret = btrfs_shrink_device(device, new_size);
1590 } /* equal, nothing need to do */
1591
1592 out_free:
1593 kfree(vol_args);
1594 out:
1595 mutex_unlock(&root->fs_info->volume_mutex);
1596 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1597 mnt_drop_write_file(file);
1598 return ret;
1599 }
1600
1601 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1602 char *name, unsigned long fd, int subvol,
1603 u64 *transid, bool readonly,
1604 struct btrfs_qgroup_inherit *inherit)
1605 {
1606 int namelen;
1607 int ret = 0;
1608
1609 ret = mnt_want_write_file(file);
1610 if (ret)
1611 goto out;
1612
1613 namelen = strlen(name);
1614 if (strchr(name, '/')) {
1615 ret = -EINVAL;
1616 goto out_drop_write;
1617 }
1618
1619 if (name[0] == '.' &&
1620 (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1621 ret = -EEXIST;
1622 goto out_drop_write;
1623 }
1624
1625 if (subvol) {
1626 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1627 NULL, transid, readonly, inherit);
1628 } else {
1629 struct fd src = fdget(fd);
1630 struct inode *src_inode;
1631 if (!src.file) {
1632 ret = -EINVAL;
1633 goto out_drop_write;
1634 }
1635
1636 src_inode = file_inode(src.file);
1637 if (src_inode->i_sb != file_inode(file)->i_sb) {
1638 btrfs_info(BTRFS_I(src_inode)->root->fs_info,
1639 "Snapshot src from another FS");
1640 ret = -EXDEV;
1641 } else if (!inode_owner_or_capable(src_inode)) {
1642 /*
1643 * Subvolume creation is not restricted, but snapshots
1644 * are limited to own subvolumes only
1645 */
1646 ret = -EPERM;
1647 } else {
1648 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1649 BTRFS_I(src_inode)->root,
1650 transid, readonly, inherit);
1651 }
1652 fdput(src);
1653 }
1654 out_drop_write:
1655 mnt_drop_write_file(file);
1656 out:
1657 return ret;
1658 }
1659
1660 static noinline int btrfs_ioctl_snap_create(struct file *file,
1661 void __user *arg, int subvol)
1662 {
1663 struct btrfs_ioctl_vol_args *vol_args;
1664 int ret;
1665
1666 vol_args = memdup_user(arg, sizeof(*vol_args));
1667 if (IS_ERR(vol_args))
1668 return PTR_ERR(vol_args);
1669 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1670
1671 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1672 vol_args->fd, subvol,
1673 NULL, false, NULL);
1674
1675 kfree(vol_args);
1676 return ret;
1677 }
1678
1679 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1680 void __user *arg, int subvol)
1681 {
1682 struct btrfs_ioctl_vol_args_v2 *vol_args;
1683 int ret;
1684 u64 transid = 0;
1685 u64 *ptr = NULL;
1686 bool readonly = false;
1687 struct btrfs_qgroup_inherit *inherit = NULL;
1688
1689 vol_args = memdup_user(arg, sizeof(*vol_args));
1690 if (IS_ERR(vol_args))
1691 return PTR_ERR(vol_args);
1692 vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1693
1694 if (vol_args->flags &
1695 ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1696 BTRFS_SUBVOL_QGROUP_INHERIT)) {
1697 ret = -EOPNOTSUPP;
1698 goto free_args;
1699 }
1700
1701 if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1702 ptr = &transid;
1703 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1704 readonly = true;
1705 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1706 if (vol_args->size > PAGE_CACHE_SIZE) {
1707 ret = -EINVAL;
1708 goto free_args;
1709 }
1710 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1711 if (IS_ERR(inherit)) {
1712 ret = PTR_ERR(inherit);
1713 goto free_args;
1714 }
1715 }
1716
1717 ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1718 vol_args->fd, subvol, ptr,
1719 readonly, inherit);
1720 if (ret)
1721 goto free_inherit;
1722
1723 if (ptr && copy_to_user(arg +
1724 offsetof(struct btrfs_ioctl_vol_args_v2,
1725 transid),
1726 ptr, sizeof(*ptr)))
1727 ret = -EFAULT;
1728
1729 free_inherit:
1730 kfree(inherit);
1731 free_args:
1732 kfree(vol_args);
1733 return ret;
1734 }
1735
1736 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1737 void __user *arg)
1738 {
1739 struct inode *inode = file_inode(file);
1740 struct btrfs_root *root = BTRFS_I(inode)->root;
1741 int ret = 0;
1742 u64 flags = 0;
1743
1744 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1745 return -EINVAL;
1746
1747 down_read(&root->fs_info->subvol_sem);
1748 if (btrfs_root_readonly(root))
1749 flags |= BTRFS_SUBVOL_RDONLY;
1750 up_read(&root->fs_info->subvol_sem);
1751
1752 if (copy_to_user(arg, &flags, sizeof(flags)))
1753 ret = -EFAULT;
1754
1755 return ret;
1756 }
1757
1758 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1759 void __user *arg)
1760 {
1761 struct inode *inode = file_inode(file);
1762 struct btrfs_root *root = BTRFS_I(inode)->root;
1763 struct btrfs_trans_handle *trans;
1764 u64 root_flags;
1765 u64 flags;
1766 int ret = 0;
1767
1768 if (!inode_owner_or_capable(inode))
1769 return -EPERM;
1770
1771 ret = mnt_want_write_file(file);
1772 if (ret)
1773 goto out;
1774
1775 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1776 ret = -EINVAL;
1777 goto out_drop_write;
1778 }
1779
1780 if (copy_from_user(&flags, arg, sizeof(flags))) {
1781 ret = -EFAULT;
1782 goto out_drop_write;
1783 }
1784
1785 if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1786 ret = -EINVAL;
1787 goto out_drop_write;
1788 }
1789
1790 if (flags & ~BTRFS_SUBVOL_RDONLY) {
1791 ret = -EOPNOTSUPP;
1792 goto out_drop_write;
1793 }
1794
1795 down_write(&root->fs_info->subvol_sem);
1796
1797 /* nothing to do */
1798 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1799 goto out_drop_sem;
1800
1801 root_flags = btrfs_root_flags(&root->root_item);
1802 if (flags & BTRFS_SUBVOL_RDONLY) {
1803 btrfs_set_root_flags(&root->root_item,
1804 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1805 } else {
1806 /*
1807 * Block RO -> RW transition if this subvolume is involved in
1808 * send
1809 */
1810 spin_lock(&root->root_item_lock);
1811 if (root->send_in_progress == 0) {
1812 btrfs_set_root_flags(&root->root_item,
1813 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1814 spin_unlock(&root->root_item_lock);
1815 } else {
1816 spin_unlock(&root->root_item_lock);
1817 btrfs_warn(root->fs_info,
1818 "Attempt to set subvolume %llu read-write during send",
1819 root->root_key.objectid);
1820 ret = -EPERM;
1821 goto out_drop_sem;
1822 }
1823 }
1824
1825 trans = btrfs_start_transaction(root, 1);
1826 if (IS_ERR(trans)) {
1827 ret = PTR_ERR(trans);
1828 goto out_reset;
1829 }
1830
1831 ret = btrfs_update_root(trans, root->fs_info->tree_root,
1832 &root->root_key, &root->root_item);
1833
1834 btrfs_commit_transaction(trans, root);
1835 out_reset:
1836 if (ret)
1837 btrfs_set_root_flags(&root->root_item, root_flags);
1838 out_drop_sem:
1839 up_write(&root->fs_info->subvol_sem);
1840 out_drop_write:
1841 mnt_drop_write_file(file);
1842 out:
1843 return ret;
1844 }
1845
1846 /*
1847 * helper to check if the subvolume references other subvolumes
1848 */
1849 static noinline int may_destroy_subvol(struct btrfs_root *root)
1850 {
1851 struct btrfs_path *path;
1852 struct btrfs_dir_item *di;
1853 struct btrfs_key key;
1854 u64 dir_id;
1855 int ret;
1856
1857 path = btrfs_alloc_path();
1858 if (!path)
1859 return -ENOMEM;
1860
1861 /* Make sure this root isn't set as the default subvol */
1862 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
1863 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
1864 dir_id, "default", 7, 0);
1865 if (di && !IS_ERR(di)) {
1866 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1867 if (key.objectid == root->root_key.objectid) {
1868 ret = -EPERM;
1869 btrfs_err(root->fs_info, "deleting default subvolume "
1870 "%llu is not allowed", key.objectid);
1871 goto out;
1872 }
1873 btrfs_release_path(path);
1874 }
1875
1876 key.objectid = root->root_key.objectid;
1877 key.type = BTRFS_ROOT_REF_KEY;
1878 key.offset = (u64)-1;
1879
1880 ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1881 &key, path, 0, 0);
1882 if (ret < 0)
1883 goto out;
1884 BUG_ON(ret == 0);
1885
1886 ret = 0;
1887 if (path->slots[0] > 0) {
1888 path->slots[0]--;
1889 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1890 if (key.objectid == root->root_key.objectid &&
1891 key.type == BTRFS_ROOT_REF_KEY)
1892 ret = -ENOTEMPTY;
1893 }
1894 out:
1895 btrfs_free_path(path);
1896 return ret;
1897 }
1898
1899 static noinline int key_in_sk(struct btrfs_key *key,
1900 struct btrfs_ioctl_search_key *sk)
1901 {
1902 struct btrfs_key test;
1903 int ret;
1904
1905 test.objectid = sk->min_objectid;
1906 test.type = sk->min_type;
1907 test.offset = sk->min_offset;
1908
1909 ret = btrfs_comp_cpu_keys(key, &test);
1910 if (ret < 0)
1911 return 0;
1912
1913 test.objectid = sk->max_objectid;
1914 test.type = sk->max_type;
1915 test.offset = sk->max_offset;
1916
1917 ret = btrfs_comp_cpu_keys(key, &test);
1918 if (ret > 0)
1919 return 0;
1920 return 1;
1921 }
1922
1923 static noinline int copy_to_sk(struct btrfs_root *root,
1924 struct btrfs_path *path,
1925 struct btrfs_key *key,
1926 struct btrfs_ioctl_search_key *sk,
1927 size_t *buf_size,
1928 char __user *ubuf,
1929 unsigned long *sk_offset,
1930 int *num_found)
1931 {
1932 u64 found_transid;
1933 struct extent_buffer *leaf;
1934 struct btrfs_ioctl_search_header sh;
1935 unsigned long item_off;
1936 unsigned long item_len;
1937 int nritems;
1938 int i;
1939 int slot;
1940 int ret = 0;
1941
1942 leaf = path->nodes[0];
1943 slot = path->slots[0];
1944 nritems = btrfs_header_nritems(leaf);
1945
1946 if (btrfs_header_generation(leaf) > sk->max_transid) {
1947 i = nritems;
1948 goto advance_key;
1949 }
1950 found_transid = btrfs_header_generation(leaf);
1951
1952 for (i = slot; i < nritems; i++) {
1953 item_off = btrfs_item_ptr_offset(leaf, i);
1954 item_len = btrfs_item_size_nr(leaf, i);
1955
1956 btrfs_item_key_to_cpu(leaf, key, i);
1957 if (!key_in_sk(key, sk))
1958 continue;
1959
1960 if (sizeof(sh) + item_len > *buf_size) {
1961 if (*num_found) {
1962 ret = 1;
1963 goto out;
1964 }
1965
1966 /*
1967 * return one empty item back for v1, which does not
1968 * handle -EOVERFLOW
1969 */
1970
1971 *buf_size = sizeof(sh) + item_len;
1972 item_len = 0;
1973 ret = -EOVERFLOW;
1974 }
1975
1976 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
1977 ret = 1;
1978 goto out;
1979 }
1980
1981 sh.objectid = key->objectid;
1982 sh.offset = key->offset;
1983 sh.type = key->type;
1984 sh.len = item_len;
1985 sh.transid = found_transid;
1986
1987 /* copy search result header */
1988 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
1989 ret = -EFAULT;
1990 goto out;
1991 }
1992
1993 *sk_offset += sizeof(sh);
1994
1995 if (item_len) {
1996 char __user *up = ubuf + *sk_offset;
1997 /* copy the item */
1998 if (read_extent_buffer_to_user(leaf, up,
1999 item_off, item_len)) {
2000 ret = -EFAULT;
2001 goto out;
2002 }
2003
2004 *sk_offset += item_len;
2005 }
2006 (*num_found)++;
2007
2008 if (ret) /* -EOVERFLOW from above */
2009 goto out;
2010
2011 if (*num_found >= sk->nr_items) {
2012 ret = 1;
2013 goto out;
2014 }
2015 }
2016 advance_key:
2017 ret = 0;
2018 if (key->offset < (u64)-1 && key->offset < sk->max_offset)
2019 key->offset++;
2020 else if (key->type < (u8)-1 && key->type < sk->max_type) {
2021 key->offset = 0;
2022 key->type++;
2023 } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
2024 key->offset = 0;
2025 key->type = 0;
2026 key->objectid++;
2027 } else
2028 ret = 1;
2029 out:
2030 /*
2031 * 0: all items from this leaf copied, continue with next
2032 * 1: * more items can be copied, but unused buffer is too small
2033 * * all items were found
2034 * Either way, it will stops the loop which iterates to the next
2035 * leaf
2036 * -EOVERFLOW: item was to large for buffer
2037 * -EFAULT: could not copy extent buffer back to userspace
2038 */
2039 return ret;
2040 }
2041
2042 static noinline int search_ioctl(struct inode *inode,
2043 struct btrfs_ioctl_search_key *sk,
2044 size_t *buf_size,
2045 char __user *ubuf)
2046 {
2047 struct btrfs_root *root;
2048 struct btrfs_key key;
2049 struct btrfs_path *path;
2050 struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
2051 int ret;
2052 int num_found = 0;
2053 unsigned long sk_offset = 0;
2054
2055 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2056 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2057 return -EOVERFLOW;
2058 }
2059
2060 path = btrfs_alloc_path();
2061 if (!path)
2062 return -ENOMEM;
2063
2064 if (sk->tree_id == 0) {
2065 /* search the root of the inode that was passed */
2066 root = BTRFS_I(inode)->root;
2067 } else {
2068 key.objectid = sk->tree_id;
2069 key.type = BTRFS_ROOT_ITEM_KEY;
2070 key.offset = (u64)-1;
2071 root = btrfs_read_fs_root_no_name(info, &key);
2072 if (IS_ERR(root)) {
2073 printk(KERN_ERR "BTRFS: could not find root %llu\n",
2074 sk->tree_id);
2075 btrfs_free_path(path);
2076 return -ENOENT;
2077 }
2078 }
2079
2080 key.objectid = sk->min_objectid;
2081 key.type = sk->min_type;
2082 key.offset = sk->min_offset;
2083
2084 while (1) {
2085 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2086 if (ret != 0) {
2087 if (ret > 0)
2088 ret = 0;
2089 goto err;
2090 }
2091 ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf,
2092 &sk_offset, &num_found);
2093 btrfs_release_path(path);
2094 if (ret)
2095 break;
2096
2097 }
2098 if (ret > 0)
2099 ret = 0;
2100 err:
2101 sk->nr_items = num_found;
2102 btrfs_free_path(path);
2103 return ret;
2104 }
2105
2106 static noinline int btrfs_ioctl_tree_search(struct file *file,
2107 void __user *argp)
2108 {
2109 struct btrfs_ioctl_search_args __user *uargs;
2110 struct btrfs_ioctl_search_key sk;
2111 struct inode *inode;
2112 int ret;
2113 size_t buf_size;
2114
2115 if (!capable(CAP_SYS_ADMIN))
2116 return -EPERM;
2117
2118 uargs = (struct btrfs_ioctl_search_args __user *)argp;
2119
2120 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2121 return -EFAULT;
2122
2123 buf_size = sizeof(uargs->buf);
2124
2125 inode = file_inode(file);
2126 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2127
2128 /*
2129 * In the origin implementation an overflow is handled by returning a
2130 * search header with a len of zero, so reset ret.
2131 */
2132 if (ret == -EOVERFLOW)
2133 ret = 0;
2134
2135 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2136 ret = -EFAULT;
2137 return ret;
2138 }
2139
2140 static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2141 void __user *argp)
2142 {
2143 struct btrfs_ioctl_search_args_v2 __user *uarg;
2144 struct btrfs_ioctl_search_args_v2 args;
2145 struct inode *inode;
2146 int ret;
2147 size_t buf_size;
2148 const size_t buf_limit = 16 * 1024 * 1024;
2149
2150 if (!capable(CAP_SYS_ADMIN))
2151 return -EPERM;
2152
2153 /* copy search header and buffer size */
2154 uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2155 if (copy_from_user(&args, uarg, sizeof(args)))
2156 return -EFAULT;
2157
2158 buf_size = args.buf_size;
2159
2160 if (buf_size < sizeof(struct btrfs_ioctl_search_header))
2161 return -EOVERFLOW;
2162
2163 /* limit result size to 16MB */
2164 if (buf_size > buf_limit)
2165 buf_size = buf_limit;
2166
2167 inode = file_inode(file);
2168 ret = search_ioctl(inode, &args.key, &buf_size,
2169 (char *)(&uarg->buf[0]));
2170 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2171 ret = -EFAULT;
2172 else if (ret == -EOVERFLOW &&
2173 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2174 ret = -EFAULT;
2175
2176 return ret;
2177 }
2178
2179 /*
2180 * Search INODE_REFs to identify path name of 'dirid' directory
2181 * in a 'tree_id' tree. and sets path name to 'name'.
2182 */
2183 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2184 u64 tree_id, u64 dirid, char *name)
2185 {
2186 struct btrfs_root *root;
2187 struct btrfs_key key;
2188 char *ptr;
2189 int ret = -1;
2190 int slot;
2191 int len;
2192 int total_len = 0;
2193 struct btrfs_inode_ref *iref;
2194 struct extent_buffer *l;
2195 struct btrfs_path *path;
2196
2197 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2198 name[0]='\0';
2199 return 0;
2200 }
2201
2202 path = btrfs_alloc_path();
2203 if (!path)
2204 return -ENOMEM;
2205
2206 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2207
2208 key.objectid = tree_id;
2209 key.type = BTRFS_ROOT_ITEM_KEY;
2210 key.offset = (u64)-1;
2211 root = btrfs_read_fs_root_no_name(info, &key);
2212 if (IS_ERR(root)) {
2213 printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id);
2214 ret = -ENOENT;
2215 goto out;
2216 }
2217
2218 key.objectid = dirid;
2219 key.type = BTRFS_INODE_REF_KEY;
2220 key.offset = (u64)-1;
2221
2222 while (1) {
2223 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2224 if (ret < 0)
2225 goto out;
2226 else if (ret > 0) {
2227 ret = btrfs_previous_item(root, path, dirid,
2228 BTRFS_INODE_REF_KEY);
2229 if (ret < 0)
2230 goto out;
2231 else if (ret > 0) {
2232 ret = -ENOENT;
2233 goto out;
2234 }
2235 }
2236
2237 l = path->nodes[0];
2238 slot = path->slots[0];
2239 btrfs_item_key_to_cpu(l, &key, slot);
2240
2241 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2242 len = btrfs_inode_ref_name_len(l, iref);
2243 ptr -= len + 1;
2244 total_len += len + 1;
2245 if (ptr < name) {
2246 ret = -ENAMETOOLONG;
2247 goto out;
2248 }
2249
2250 *(ptr + len) = '/';
2251 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2252
2253 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2254 break;
2255
2256 btrfs_release_path(path);
2257 key.objectid = key.offset;
2258 key.offset = (u64)-1;
2259 dirid = key.objectid;
2260 }
2261 memmove(name, ptr, total_len);
2262 name[total_len] = '\0';
2263 ret = 0;
2264 out:
2265 btrfs_free_path(path);
2266 return ret;
2267 }
2268
2269 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2270 void __user *argp)
2271 {
2272 struct btrfs_ioctl_ino_lookup_args *args;
2273 struct inode *inode;
2274 int ret;
2275
2276 if (!capable(CAP_SYS_ADMIN))
2277 return -EPERM;
2278
2279 args = memdup_user(argp, sizeof(*args));
2280 if (IS_ERR(args))
2281 return PTR_ERR(args);
2282
2283 inode = file_inode(file);
2284
2285 if (args->treeid == 0)
2286 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2287
2288 ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2289 args->treeid, args->objectid,
2290 args->name);
2291
2292 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2293 ret = -EFAULT;
2294
2295 kfree(args);
2296 return ret;
2297 }
2298
2299 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2300 void __user *arg)
2301 {
2302 struct dentry *parent = file->f_path.dentry;
2303 struct dentry *dentry;
2304 struct inode *dir = d_inode(parent);
2305 struct inode *inode;
2306 struct btrfs_root *root = BTRFS_I(dir)->root;
2307 struct btrfs_root *dest = NULL;
2308 struct btrfs_ioctl_vol_args *vol_args;
2309 struct btrfs_trans_handle *trans;
2310 struct btrfs_block_rsv block_rsv;
2311 u64 root_flags;
2312 u64 qgroup_reserved;
2313 int namelen;
2314 int ret;
2315 int err = 0;
2316
2317 vol_args = memdup_user(arg, sizeof(*vol_args));
2318 if (IS_ERR(vol_args))
2319 return PTR_ERR(vol_args);
2320
2321 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2322 namelen = strlen(vol_args->name);
2323 if (strchr(vol_args->name, '/') ||
2324 strncmp(vol_args->name, "..", namelen) == 0) {
2325 err = -EINVAL;
2326 goto out;
2327 }
2328
2329 err = mnt_want_write_file(file);
2330 if (err)
2331 goto out;
2332
2333
2334 err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
2335 if (err == -EINTR)
2336 goto out_drop_write;
2337 dentry = lookup_one_len(vol_args->name, parent, namelen);
2338 if (IS_ERR(dentry)) {
2339 err = PTR_ERR(dentry);
2340 goto out_unlock_dir;
2341 }
2342
2343 if (d_really_is_negative(dentry)) {
2344 err = -ENOENT;
2345 goto out_dput;
2346 }
2347
2348 inode = d_inode(dentry);
2349 dest = BTRFS_I(inode)->root;
2350 if (!capable(CAP_SYS_ADMIN)) {
2351 /*
2352 * Regular user. Only allow this with a special mount
2353 * option, when the user has write+exec access to the
2354 * subvol root, and when rmdir(2) would have been
2355 * allowed.
2356 *
2357 * Note that this is _not_ check that the subvol is
2358 * empty or doesn't contain data that we wouldn't
2359 * otherwise be able to delete.
2360 *
2361 * Users who want to delete empty subvols should try
2362 * rmdir(2).
2363 */
2364 err = -EPERM;
2365 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2366 goto out_dput;
2367
2368 /*
2369 * Do not allow deletion if the parent dir is the same
2370 * as the dir to be deleted. That means the ioctl
2371 * must be called on the dentry referencing the root
2372 * of the subvol, not a random directory contained
2373 * within it.
2374 */
2375 err = -EINVAL;
2376 if (root == dest)
2377 goto out_dput;
2378
2379 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2380 if (err)
2381 goto out_dput;
2382 }
2383
2384 /* check if subvolume may be deleted by a user */
2385 err = btrfs_may_delete(dir, dentry, 1);
2386 if (err)
2387 goto out_dput;
2388
2389 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2390 err = -EINVAL;
2391 goto out_dput;
2392 }
2393
2394 mutex_lock(&inode->i_mutex);
2395
2396 /*
2397 * Don't allow to delete a subvolume with send in progress. This is
2398 * inside the i_mutex so the error handling that has to drop the bit
2399 * again is not run concurrently.
2400 */
2401 spin_lock(&dest->root_item_lock);
2402 root_flags = btrfs_root_flags(&dest->root_item);
2403 if (dest->send_in_progress == 0) {
2404 btrfs_set_root_flags(&dest->root_item,
2405 root_flags | BTRFS_ROOT_SUBVOL_DEAD);
2406 spin_unlock(&dest->root_item_lock);
2407 } else {
2408 spin_unlock(&dest->root_item_lock);
2409 btrfs_warn(root->fs_info,
2410 "Attempt to delete subvolume %llu during send",
2411 dest->root_key.objectid);
2412 err = -EPERM;
2413 goto out_dput;
2414 }
2415
2416 d_invalidate(dentry);
2417
2418 down_write(&root->fs_info->subvol_sem);
2419
2420 err = may_destroy_subvol(dest);
2421 if (err)
2422 goto out_up_write;
2423
2424 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2425 /*
2426 * One for dir inode, two for dir entries, two for root
2427 * ref/backref.
2428 */
2429 err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2430 5, &qgroup_reserved, true);
2431 if (err)
2432 goto out_up_write;
2433
2434 trans = btrfs_start_transaction(root, 0);
2435 if (IS_ERR(trans)) {
2436 err = PTR_ERR(trans);
2437 goto out_release;
2438 }
2439 trans->block_rsv = &block_rsv;
2440 trans->bytes_reserved = block_rsv.size;
2441
2442 ret = btrfs_unlink_subvol(trans, root, dir,
2443 dest->root_key.objectid,
2444 dentry->d_name.name,
2445 dentry->d_name.len);
2446 if (ret) {
2447 err = ret;
2448 btrfs_abort_transaction(trans, root, ret);
2449 goto out_end_trans;
2450 }
2451
2452 btrfs_record_root_in_trans(trans, dest);
2453
2454 memset(&dest->root_item.drop_progress, 0,
2455 sizeof(dest->root_item.drop_progress));
2456 dest->root_item.drop_level = 0;
2457 btrfs_set_root_refs(&dest->root_item, 0);
2458
2459 if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
2460 ret = btrfs_insert_orphan_item(trans,
2461 root->fs_info->tree_root,
2462 dest->root_key.objectid);
2463 if (ret) {
2464 btrfs_abort_transaction(trans, root, ret);
2465 err = ret;
2466 goto out_end_trans;
2467 }
2468 }
2469
2470 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2471 dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
2472 dest->root_key.objectid);
2473 if (ret && ret != -ENOENT) {
2474 btrfs_abort_transaction(trans, root, ret);
2475 err = ret;
2476 goto out_end_trans;
2477 }
2478 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
2479 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2480 dest->root_item.received_uuid,
2481 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
2482 dest->root_key.objectid);
2483 if (ret && ret != -ENOENT) {
2484 btrfs_abort_transaction(trans, root, ret);
2485 err = ret;
2486 goto out_end_trans;
2487 }
2488 }
2489
2490 out_end_trans:
2491 trans->block_rsv = NULL;
2492 trans->bytes_reserved = 0;
2493 ret = btrfs_end_transaction(trans, root);
2494 if (ret && !err)
2495 err = ret;
2496 inode->i_flags |= S_DEAD;
2497 out_release:
2498 btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2499 out_up_write:
2500 up_write(&root->fs_info->subvol_sem);
2501 if (err) {
2502 spin_lock(&dest->root_item_lock);
2503 root_flags = btrfs_root_flags(&dest->root_item);
2504 btrfs_set_root_flags(&dest->root_item,
2505 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
2506 spin_unlock(&dest->root_item_lock);
2507 }
2508 mutex_unlock(&inode->i_mutex);
2509 if (!err) {
2510 shrink_dcache_sb(root->fs_info->sb);
2511 btrfs_invalidate_inodes(dest);
2512 d_delete(dentry);
2513 ASSERT(dest->send_in_progress == 0);
2514
2515 /* the last ref */
2516 if (dest->ino_cache_inode) {
2517 iput(dest->ino_cache_inode);
2518 dest->ino_cache_inode = NULL;
2519 }
2520 }
2521 out_dput:
2522 dput(dentry);
2523 out_unlock_dir:
2524 mutex_unlock(&dir->i_mutex);
2525 out_drop_write:
2526 mnt_drop_write_file(file);
2527 out:
2528 kfree(vol_args);
2529 return err;
2530 }
2531
2532 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2533 {
2534 struct inode *inode = file_inode(file);
2535 struct btrfs_root *root = BTRFS_I(inode)->root;
2536 struct btrfs_ioctl_defrag_range_args *range;
2537 int ret;
2538
2539 ret = mnt_want_write_file(file);
2540 if (ret)
2541 return ret;
2542
2543 if (btrfs_root_readonly(root)) {
2544 ret = -EROFS;
2545 goto out;
2546 }
2547
2548 switch (inode->i_mode & S_IFMT) {
2549 case S_IFDIR:
2550 if (!capable(CAP_SYS_ADMIN)) {
2551 ret = -EPERM;
2552 goto out;
2553 }
2554 ret = btrfs_defrag_root(root);
2555 if (ret)
2556 goto out;
2557 ret = btrfs_defrag_root(root->fs_info->extent_root);
2558 break;
2559 case S_IFREG:
2560 if (!(file->f_mode & FMODE_WRITE)) {
2561 ret = -EINVAL;
2562 goto out;
2563 }
2564
2565 range = kzalloc(sizeof(*range), GFP_KERNEL);
2566 if (!range) {
2567 ret = -ENOMEM;
2568 goto out;
2569 }
2570
2571 if (argp) {
2572 if (copy_from_user(range, argp,
2573 sizeof(*range))) {
2574 ret = -EFAULT;
2575 kfree(range);
2576 goto out;
2577 }
2578 /* compression requires us to start the IO */
2579 if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2580 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2581 range->extent_thresh = (u32)-1;
2582 }
2583 } else {
2584 /* the rest are all set to zero by kzalloc */
2585 range->len = (u64)-1;
2586 }
2587 ret = btrfs_defrag_file(file_inode(file), file,
2588 range, 0, 0);
2589 if (ret > 0)
2590 ret = 0;
2591 kfree(range);
2592 break;
2593 default:
2594 ret = -EINVAL;
2595 }
2596 out:
2597 mnt_drop_write_file(file);
2598 return ret;
2599 }
2600
2601 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2602 {
2603 struct btrfs_ioctl_vol_args *vol_args;
2604 int ret;
2605
2606 if (!capable(CAP_SYS_ADMIN))
2607 return -EPERM;
2608
2609 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2610 1)) {
2611 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2612 }
2613
2614 mutex_lock(&root->fs_info->volume_mutex);
2615 vol_args = memdup_user(arg, sizeof(*vol_args));
2616 if (IS_ERR(vol_args)) {
2617 ret = PTR_ERR(vol_args);
2618 goto out;
2619 }
2620
2621 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2622 ret = btrfs_init_new_device(root, vol_args->name);
2623
2624 if (!ret)
2625 btrfs_info(root->fs_info, "disk added %s",vol_args->name);
2626
2627 kfree(vol_args);
2628 out:
2629 mutex_unlock(&root->fs_info->volume_mutex);
2630 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2631 return ret;
2632 }
2633
2634 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2635 {
2636 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
2637 struct btrfs_ioctl_vol_args *vol_args;
2638 int ret;
2639
2640 if (!capable(CAP_SYS_ADMIN))
2641 return -EPERM;
2642
2643 ret = mnt_want_write_file(file);
2644 if (ret)
2645 return ret;
2646
2647 vol_args = memdup_user(arg, sizeof(*vol_args));
2648 if (IS_ERR(vol_args)) {
2649 ret = PTR_ERR(vol_args);
2650 goto err_drop;
2651 }
2652
2653 vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2654
2655 if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2656 1)) {
2657 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2658 goto out;
2659 }
2660
2661 mutex_lock(&root->fs_info->volume_mutex);
2662 ret = btrfs_rm_device(root, vol_args->name);
2663 mutex_unlock(&root->fs_info->volume_mutex);
2664 atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2665
2666 if (!ret)
2667 btrfs_info(root->fs_info, "disk deleted %s",vol_args->name);
2668
2669 out:
2670 kfree(vol_args);
2671 err_drop:
2672 mnt_drop_write_file(file);
2673 return ret;
2674 }
2675
2676 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2677 {
2678 struct btrfs_ioctl_fs_info_args *fi_args;
2679 struct btrfs_device *device;
2680 struct btrfs_device *next;
2681 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2682 int ret = 0;
2683
2684 fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2685 if (!fi_args)
2686 return -ENOMEM;
2687
2688 mutex_lock(&fs_devices->device_list_mutex);
2689 fi_args->num_devices = fs_devices->num_devices;
2690 memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2691
2692 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2693 if (device->devid > fi_args->max_id)
2694 fi_args->max_id = device->devid;
2695 }
2696 mutex_unlock(&fs_devices->device_list_mutex);
2697
2698 fi_args->nodesize = root->fs_info->super_copy->nodesize;
2699 fi_args->sectorsize = root->fs_info->super_copy->sectorsize;
2700 fi_args->clone_alignment = root->fs_info->super_copy->sectorsize;
2701
2702 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2703 ret = -EFAULT;
2704
2705 kfree(fi_args);
2706 return ret;
2707 }
2708
2709 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2710 {
2711 struct btrfs_ioctl_dev_info_args *di_args;
2712 struct btrfs_device *dev;
2713 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2714 int ret = 0;
2715 char *s_uuid = NULL;
2716
2717 di_args = memdup_user(arg, sizeof(*di_args));
2718 if (IS_ERR(di_args))
2719 return PTR_ERR(di_args);
2720
2721 if (!btrfs_is_empty_uuid(di_args->uuid))
2722 s_uuid = di_args->uuid;
2723
2724 mutex_lock(&fs_devices->device_list_mutex);
2725 dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2726
2727 if (!dev) {
2728 ret = -ENODEV;
2729 goto out;
2730 }
2731
2732 di_args->devid = dev->devid;
2733 di_args->bytes_used = btrfs_device_get_bytes_used(dev);
2734 di_args->total_bytes = btrfs_device_get_total_bytes(dev);
2735 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2736 if (dev->name) {
2737 struct rcu_string *name;
2738
2739 rcu_read_lock();
2740 name = rcu_dereference(dev->name);
2741 strncpy(di_args->path, name->str, sizeof(di_args->path));
2742 rcu_read_unlock();
2743 di_args->path[sizeof(di_args->path) - 1] = 0;
2744 } else {
2745 di_args->path[0] = '\0';
2746 }
2747
2748 out:
2749 mutex_unlock(&fs_devices->device_list_mutex);
2750 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2751 ret = -EFAULT;
2752
2753 kfree(di_args);
2754 return ret;
2755 }
2756
2757 static struct page *extent_same_get_page(struct inode *inode, u64 off)
2758 {
2759 struct page *page;
2760 pgoff_t index;
2761 struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
2762
2763 index = off >> PAGE_CACHE_SHIFT;
2764
2765 page = grab_cache_page(inode->i_mapping, index);
2766 if (!page)
2767 return NULL;
2768
2769 if (!PageUptodate(page)) {
2770 if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
2771 0))
2772 return NULL;
2773 lock_page(page);
2774 if (!PageUptodate(page)) {
2775 unlock_page(page);
2776 page_cache_release(page);
2777 return NULL;
2778 }
2779 }
2780 unlock_page(page);
2781
2782 return page;
2783 }
2784
2785 static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
2786 {
2787 /* do any pending delalloc/csum calc on src, one way or
2788 another, and lock file content */
2789 while (1) {
2790 struct btrfs_ordered_extent *ordered;
2791 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2792 ordered = btrfs_lookup_first_ordered_extent(inode,
2793 off + len - 1);
2794 if ((!ordered ||
2795 ordered->file_offset + ordered->len <= off ||
2796 ordered->file_offset >= off + len) &&
2797 !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2798 off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
2799 if (ordered)
2800 btrfs_put_ordered_extent(ordered);
2801 break;
2802 }
2803 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2804 if (ordered)
2805 btrfs_put_ordered_extent(ordered);
2806 btrfs_wait_ordered_range(inode, off, len);
2807 }
2808 }
2809
2810 static void btrfs_double_unlock(struct inode *inode1, u64 loff1,
2811 struct inode *inode2, u64 loff2, u64 len)
2812 {
2813 unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
2814 unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
2815
2816 mutex_unlock(&inode1->i_mutex);
2817 mutex_unlock(&inode2->i_mutex);
2818 }
2819
2820 static void btrfs_double_lock(struct inode *inode1, u64 loff1,
2821 struct inode *inode2, u64 loff2, u64 len)
2822 {
2823 if (inode1 < inode2) {
2824 swap(inode1, inode2);
2825 swap(loff1, loff2);
2826 }
2827
2828 mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
2829 lock_extent_range(inode1, loff1, len);
2830 if (inode1 != inode2) {
2831 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
2832 lock_extent_range(inode2, loff2, len);
2833 }
2834 }
2835
2836 static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
2837 u64 dst_loff, u64 len)
2838 {
2839 int ret = 0;
2840 struct page *src_page, *dst_page;
2841 unsigned int cmp_len = PAGE_CACHE_SIZE;
2842 void *addr, *dst_addr;
2843
2844 while (len) {
2845 if (len < PAGE_CACHE_SIZE)
2846 cmp_len = len;
2847
2848 src_page = extent_same_get_page(src, loff);
2849 if (!src_page)
2850 return -EINVAL;
2851 dst_page = extent_same_get_page(dst, dst_loff);
2852 if (!dst_page) {
2853 page_cache_release(src_page);
2854 return -EINVAL;
2855 }
2856 addr = kmap_atomic(src_page);
2857 dst_addr = kmap_atomic(dst_page);
2858
2859 flush_dcache_page(src_page);
2860 flush_dcache_page(dst_page);
2861
2862 if (memcmp(addr, dst_addr, cmp_len))
2863 ret = BTRFS_SAME_DATA_DIFFERS;
2864
2865 kunmap_atomic(addr);
2866 kunmap_atomic(dst_addr);
2867 page_cache_release(src_page);
2868 page_cache_release(dst_page);
2869
2870 if (ret)
2871 break;
2872
2873 loff += cmp_len;
2874 dst_loff += cmp_len;
2875 len -= cmp_len;
2876 }
2877
2878 return ret;
2879 }
2880
2881 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len)
2882 {
2883 u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
2884
2885 if (off + len > inode->i_size || off + len < off)
2886 return -EINVAL;
2887 /* Check that we are block aligned - btrfs_clone() requires this */
2888 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
2889 return -EINVAL;
2890
2891 return 0;
2892 }
2893
2894 static int btrfs_extent_same(struct inode *src, u64 loff, u64 len,
2895 struct inode *dst, u64 dst_loff)
2896 {
2897 int ret;
2898
2899 /*
2900 * btrfs_clone() can't handle extents in the same file
2901 * yet. Once that works, we can drop this check and replace it
2902 * with a check for the same inode, but overlapping extents.
2903 */
2904 if (src == dst)
2905 return -EINVAL;
2906
2907 if (len == 0)
2908 return 0;
2909
2910 btrfs_double_lock(src, loff, dst, dst_loff, len);
2911
2912 ret = extent_same_check_offsets(src, loff, len);
2913 if (ret)
2914 goto out_unlock;
2915
2916 ret = extent_same_check_offsets(dst, dst_loff, len);
2917 if (ret)
2918 goto out_unlock;
2919
2920 /* don't make the dst file partly checksummed */
2921 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2922 (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
2923 ret = -EINVAL;
2924 goto out_unlock;
2925 }
2926
2927 ret = btrfs_cmp_data(src, loff, dst, dst_loff, len);
2928 if (ret == 0)
2929 ret = btrfs_clone(src, dst, loff, len, len, dst_loff);
2930
2931 out_unlock:
2932 btrfs_double_unlock(src, loff, dst, dst_loff, len);
2933
2934 return ret;
2935 }
2936
2937 #define BTRFS_MAX_DEDUPE_LEN (16 * 1024 * 1024)
2938
2939 static long btrfs_ioctl_file_extent_same(struct file *file,
2940 struct btrfs_ioctl_same_args __user *argp)
2941 {
2942 struct btrfs_ioctl_same_args *same;
2943 struct btrfs_ioctl_same_extent_info *info;
2944 struct inode *src = file_inode(file);
2945 u64 off;
2946 u64 len;
2947 int i;
2948 int ret;
2949 unsigned long size;
2950 u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
2951 bool is_admin = capable(CAP_SYS_ADMIN);
2952 u16 count;
2953
2954 if (!(file->f_mode & FMODE_READ))
2955 return -EINVAL;
2956
2957 ret = mnt_want_write_file(file);
2958 if (ret)
2959 return ret;
2960
2961 if (get_user(count, &argp->dest_count)) {
2962 ret = -EFAULT;
2963 goto out;
2964 }
2965
2966 size = offsetof(struct btrfs_ioctl_same_args __user, info[count]);
2967
2968 same = memdup_user(argp, size);
2969
2970 if (IS_ERR(same)) {
2971 ret = PTR_ERR(same);
2972 goto out;
2973 }
2974
2975 off = same->logical_offset;
2976 len = same->length;
2977
2978 /*
2979 * Limit the total length we will dedupe for each operation.
2980 * This is intended to bound the total time spent in this
2981 * ioctl to something sane.
2982 */
2983 if (len > BTRFS_MAX_DEDUPE_LEN)
2984 len = BTRFS_MAX_DEDUPE_LEN;
2985
2986 if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
2987 /*
2988 * Btrfs does not support blocksize < page_size. As a
2989 * result, btrfs_cmp_data() won't correctly handle
2990 * this situation without an update.
2991 */
2992 ret = -EINVAL;
2993 goto out;
2994 }
2995
2996 ret = -EISDIR;
2997 if (S_ISDIR(src->i_mode))
2998 goto out;
2999
3000 ret = -EACCES;
3001 if (!S_ISREG(src->i_mode))
3002 goto out;
3003
3004 /* pre-format output fields to sane values */
3005 for (i = 0; i < count; i++) {
3006 same->info[i].bytes_deduped = 0ULL;
3007 same->info[i].status = 0;
3008 }
3009
3010 for (i = 0, info = same->info; i < count; i++, info++) {
3011 struct inode *dst;
3012 struct fd dst_file = fdget(info->fd);
3013 if (!dst_file.file) {
3014 info->status = -EBADF;
3015 continue;
3016 }
3017 dst = file_inode(dst_file.file);
3018
3019 if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) {
3020 info->status = -EINVAL;
3021 } else if (file->f_path.mnt != dst_file.file->f_path.mnt) {
3022 info->status = -EXDEV;
3023 } else if (S_ISDIR(dst->i_mode)) {
3024 info->status = -EISDIR;
3025 } else if (!S_ISREG(dst->i_mode)) {
3026 info->status = -EACCES;
3027 } else {
3028 info->status = btrfs_extent_same(src, off, len, dst,
3029 info->logical_offset);
3030 if (info->status == 0)
3031 info->bytes_deduped += len;
3032 }
3033 fdput(dst_file);
3034 }
3035
3036 ret = copy_to_user(argp, same, size);
3037 if (ret)
3038 ret = -EFAULT;
3039
3040 out:
3041 mnt_drop_write_file(file);
3042 return ret;
3043 }
3044
3045 /* Helper to check and see if this root currently has a ref on the given disk
3046 * bytenr. If it does then we need to update the quota for this root. This
3047 * doesn't do anything if quotas aren't enabled.
3048 */
3049 static int check_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3050 u64 disko)
3051 {
3052 struct seq_list tree_mod_seq_elem = SEQ_LIST_INIT(tree_mod_seq_elem);
3053 struct ulist *roots;
3054 struct ulist_iterator uiter;
3055 struct ulist_node *root_node = NULL;
3056 int ret;
3057
3058 if (!root->fs_info->quota_enabled)
3059 return 1;
3060
3061 btrfs_get_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3062 ret = btrfs_find_all_roots(trans, root->fs_info, disko,
3063 tree_mod_seq_elem.seq, &roots);
3064 if (ret < 0)
3065 goto out;
3066 ret = 0;
3067 ULIST_ITER_INIT(&uiter);
3068 while ((root_node = ulist_next(roots, &uiter))) {
3069 if (root_node->val == root->objectid) {
3070 ret = 1;
3071 break;
3072 }
3073 }
3074 ulist_free(roots);
3075 out:
3076 btrfs_put_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3077 return ret;
3078 }
3079
3080 static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3081 struct inode *inode,
3082 u64 endoff,
3083 const u64 destoff,
3084 const u64 olen)
3085 {
3086 struct btrfs_root *root = BTRFS_I(inode)->root;
3087 int ret;
3088
3089 inode_inc_iversion(inode);
3090 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3091 /*
3092 * We round up to the block size at eof when determining which
3093 * extents to clone above, but shouldn't round up the file size.
3094 */
3095 if (endoff > destoff + olen)
3096 endoff = destoff + olen;
3097 if (endoff > inode->i_size)
3098 btrfs_i_size_write(inode, endoff);
3099
3100 ret = btrfs_update_inode(trans, root, inode);
3101 if (ret) {
3102 btrfs_abort_transaction(trans, root, ret);
3103 btrfs_end_transaction(trans, root);
3104 goto out;
3105 }
3106 ret = btrfs_end_transaction(trans, root);
3107 out:
3108 return ret;
3109 }
3110
3111 static void clone_update_extent_map(struct inode *inode,
3112 const struct btrfs_trans_handle *trans,
3113 const struct btrfs_path *path,
3114 const u64 hole_offset,
3115 const u64 hole_len)
3116 {
3117 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
3118 struct extent_map *em;
3119 int ret;
3120
3121 em = alloc_extent_map();
3122 if (!em) {
3123 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3124 &BTRFS_I(inode)->runtime_flags);
3125 return;
3126 }
3127
3128 if (path) {
3129 struct btrfs_file_extent_item *fi;
3130
3131 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
3132 struct btrfs_file_extent_item);
3133 btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
3134 em->generation = -1;
3135 if (btrfs_file_extent_type(path->nodes[0], fi) ==
3136 BTRFS_FILE_EXTENT_INLINE)
3137 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3138 &BTRFS_I(inode)->runtime_flags);
3139 } else {
3140 em->start = hole_offset;
3141 em->len = hole_len;
3142 em->ram_bytes = em->len;
3143 em->orig_start = hole_offset;
3144 em->block_start = EXTENT_MAP_HOLE;
3145 em->block_len = 0;
3146 em->orig_block_len = 0;
3147 em->compress_type = BTRFS_COMPRESS_NONE;
3148 em->generation = trans->transid;
3149 }
3150
3151 while (1) {
3152 write_lock(&em_tree->lock);
3153 ret = add_extent_mapping(em_tree, em, 1);
3154 write_unlock(&em_tree->lock);
3155 if (ret != -EEXIST) {
3156 free_extent_map(em);
3157 break;
3158 }
3159 btrfs_drop_extent_cache(inode, em->start,
3160 em->start + em->len - 1, 0);
3161 }
3162
3163 if (ret)
3164 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3165 &BTRFS_I(inode)->runtime_flags);
3166 }
3167
3168 /**
3169 * btrfs_clone() - clone a range from inode file to another
3170 *
3171 * @src: Inode to clone from
3172 * @inode: Inode to clone to
3173 * @off: Offset within source to start clone from
3174 * @olen: Original length, passed by user, of range to clone
3175 * @olen_aligned: Block-aligned value of olen, extent_same uses
3176 * identical values here
3177 * @destoff: Offset within @inode to start clone
3178 */
3179 static int btrfs_clone(struct inode *src, struct inode *inode,
3180 const u64 off, const u64 olen, const u64 olen_aligned,
3181 const u64 destoff)
3182 {
3183 struct btrfs_root *root = BTRFS_I(inode)->root;
3184 struct btrfs_path *path = NULL;
3185 struct extent_buffer *leaf;
3186 struct btrfs_trans_handle *trans;
3187 char *buf = NULL;
3188 struct btrfs_key key;
3189 u32 nritems;
3190 int slot;
3191 int ret;
3192 int no_quota;
3193 const u64 len = olen_aligned;
3194 u64 last_disko = 0;
3195 u64 last_dest_end = destoff;
3196
3197 ret = -ENOMEM;
3198 buf = vmalloc(root->nodesize);
3199 if (!buf)
3200 return ret;
3201
3202 path = btrfs_alloc_path();
3203 if (!path) {
3204 vfree(buf);
3205 return ret;
3206 }
3207
3208 path->reada = 2;
3209 /* clone data */
3210 key.objectid = btrfs_ino(src);
3211 key.type = BTRFS_EXTENT_DATA_KEY;
3212 key.offset = off;
3213
3214 while (1) {
3215 u64 next_key_min_offset = key.offset + 1;
3216
3217 /*
3218 * note the key will change type as we walk through the
3219 * tree.
3220 */
3221 path->leave_spinning = 1;
3222 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3223 0, 0);
3224 if (ret < 0)
3225 goto out;
3226 /*
3227 * First search, if no extent item that starts at offset off was
3228 * found but the previous item is an extent item, it's possible
3229 * it might overlap our target range, therefore process it.
3230 */
3231 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3232 btrfs_item_key_to_cpu(path->nodes[0], &key,
3233 path->slots[0] - 1);
3234 if (key.type == BTRFS_EXTENT_DATA_KEY)
3235 path->slots[0]--;
3236 }
3237
3238 nritems = btrfs_header_nritems(path->nodes[0]);
3239 process_slot:
3240 no_quota = 1;
3241 if (path->slots[0] >= nritems) {
3242 ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3243 if (ret < 0)
3244 goto out;
3245 if (ret > 0)
3246 break;
3247 nritems = btrfs_header_nritems(path->nodes[0]);
3248 }
3249 leaf = path->nodes[0];
3250 slot = path->slots[0];
3251
3252 btrfs_item_key_to_cpu(leaf, &key, slot);
3253 if (key.type > BTRFS_EXTENT_DATA_KEY ||
3254 key.objectid != btrfs_ino(src))
3255 break;
3256
3257 if (key.type == BTRFS_EXTENT_DATA_KEY) {
3258 struct btrfs_file_extent_item *extent;
3259 int type;
3260 u32 size;
3261 struct btrfs_key new_key;
3262 u64 disko = 0, diskl = 0;
3263 u64 datao = 0, datal = 0;
3264 u8 comp;
3265 u64 drop_start;
3266
3267 extent = btrfs_item_ptr(leaf, slot,
3268 struct btrfs_file_extent_item);
3269 comp = btrfs_file_extent_compression(leaf, extent);
3270 type = btrfs_file_extent_type(leaf, extent);
3271 if (type == BTRFS_FILE_EXTENT_REG ||
3272 type == BTRFS_FILE_EXTENT_PREALLOC) {
3273 disko = btrfs_file_extent_disk_bytenr(leaf,
3274 extent);
3275 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3276 extent);
3277 datao = btrfs_file_extent_offset(leaf, extent);
3278 datal = btrfs_file_extent_num_bytes(leaf,
3279 extent);
3280 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3281 /* take upper bound, may be compressed */
3282 datal = btrfs_file_extent_ram_bytes(leaf,
3283 extent);
3284 }
3285
3286 /*
3287 * The first search might have left us at an extent
3288 * item that ends before our target range's start, can
3289 * happen if we have holes and NO_HOLES feature enabled.
3290 */
3291 if (key.offset + datal <= off) {
3292 path->slots[0]++;
3293 goto process_slot;
3294 } else if (key.offset >= off + len) {
3295 break;
3296 }
3297 next_key_min_offset = key.offset + datal;
3298 size = btrfs_item_size_nr(leaf, slot);
3299 read_extent_buffer(leaf, buf,
3300 btrfs_item_ptr_offset(leaf, slot),
3301 size);
3302
3303 btrfs_release_path(path);
3304 path->leave_spinning = 0;
3305
3306 memcpy(&new_key, &key, sizeof(new_key));
3307 new_key.objectid = btrfs_ino(inode);
3308 if (off <= key.offset)
3309 new_key.offset = key.offset + destoff - off;
3310 else
3311 new_key.offset = destoff;
3312
3313 /*
3314 * Deal with a hole that doesn't have an extent item
3315 * that represents it (NO_HOLES feature enabled).
3316 * This hole is either in the middle of the cloning
3317 * range or at the beginning (fully overlaps it or
3318 * partially overlaps it).
3319 */
3320 if (new_key.offset != last_dest_end)
3321 drop_start = last_dest_end;
3322 else
3323 drop_start = new_key.offset;
3324
3325 /*
3326 * 1 - adjusting old extent (we may have to split it)
3327 * 1 - add new extent
3328 * 1 - inode update
3329 */
3330 trans = btrfs_start_transaction(root, 3);
3331 if (IS_ERR(trans)) {
3332 ret = PTR_ERR(trans);
3333 goto out;
3334 }
3335
3336 if (type == BTRFS_FILE_EXTENT_REG ||
3337 type == BTRFS_FILE_EXTENT_PREALLOC) {
3338 /*
3339 * a | --- range to clone ---| b
3340 * | ------------- extent ------------- |
3341 */
3342
3343 /* subtract range b */
3344 if (key.offset + datal > off + len)
3345 datal = off + len - key.offset;
3346
3347 /* subtract range a */
3348 if (off > key.offset) {
3349 datao += off - key.offset;
3350 datal -= off - key.offset;
3351 }
3352
3353 ret = btrfs_drop_extents(trans, root, inode,
3354 drop_start,
3355 new_key.offset + datal,
3356 1);
3357 if (ret) {
3358 if (ret != -EOPNOTSUPP)
3359 btrfs_abort_transaction(trans,
3360 root, ret);
3361 btrfs_end_transaction(trans, root);
3362 goto out;
3363 }
3364
3365 ret = btrfs_insert_empty_item(trans, root, path,
3366 &new_key, size);
3367 if (ret) {
3368 btrfs_abort_transaction(trans, root,
3369 ret);
3370 btrfs_end_transaction(trans, root);
3371 goto out;
3372 }
3373
3374 leaf = path->nodes[0];
3375 slot = path->slots[0];
3376 write_extent_buffer(leaf, buf,
3377 btrfs_item_ptr_offset(leaf, slot),
3378 size);
3379
3380 extent = btrfs_item_ptr(leaf, slot,
3381 struct btrfs_file_extent_item);
3382
3383 /* disko == 0 means it's a hole */
3384 if (!disko)
3385 datao = 0;
3386
3387 btrfs_set_file_extent_offset(leaf, extent,
3388 datao);
3389 btrfs_set_file_extent_num_bytes(leaf, extent,
3390 datal);
3391
3392 /*
3393 * We need to look up the roots that point at
3394 * this bytenr and see if the new root does. If
3395 * it does not we need to make sure we update
3396 * quotas appropriately.
3397 */
3398 if (disko && root != BTRFS_I(src)->root &&
3399 disko != last_disko) {
3400 no_quota = check_ref(trans, root,
3401 disko);
3402 if (no_quota < 0) {
3403 btrfs_abort_transaction(trans,
3404 root,
3405 ret);
3406 btrfs_end_transaction(trans,
3407 root);
3408 ret = no_quota;
3409 goto out;
3410 }
3411 }
3412
3413 if (disko) {
3414 inode_add_bytes(inode, datal);
3415 ret = btrfs_inc_extent_ref(trans, root,
3416 disko, diskl, 0,
3417 root->root_key.objectid,
3418 btrfs_ino(inode),
3419 new_key.offset - datao,
3420 no_quota);
3421 if (ret) {
3422 btrfs_abort_transaction(trans,
3423 root,
3424 ret);
3425 btrfs_end_transaction(trans,
3426 root);
3427 goto out;
3428
3429 }
3430 }
3431 } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3432 u64 skip = 0;
3433 u64 trim = 0;
3434 u64 aligned_end = 0;
3435
3436 if (off > key.offset) {
3437 skip = off - key.offset;
3438 new_key.offset += skip;
3439 }
3440
3441 if (key.offset + datal > off + len)
3442 trim = key.offset + datal - (off + len);
3443
3444 if (comp && (skip || trim)) {
3445 ret = -EINVAL;
3446 btrfs_end_transaction(trans, root);
3447 goto out;
3448 }
3449 size -= skip + trim;
3450 datal -= skip + trim;
3451
3452 aligned_end = ALIGN(new_key.offset + datal,
3453 root->sectorsize);
3454 ret = btrfs_drop_extents(trans, root, inode,
3455 drop_start,
3456 aligned_end,
3457 1);
3458 if (ret) {
3459 if (ret != -EOPNOTSUPP)
3460 btrfs_abort_transaction(trans,
3461 root, ret);
3462 btrfs_end_transaction(trans, root);
3463 goto out;
3464 }
3465
3466 ret = btrfs_insert_empty_item(trans, root, path,
3467 &new_key, size);
3468 if (ret) {
3469 btrfs_abort_transaction(trans, root,
3470 ret);
3471 btrfs_end_transaction(trans, root);
3472 goto out;
3473 }
3474
3475 if (skip) {
3476 u32 start =
3477 btrfs_file_extent_calc_inline_size(0);
3478 memmove(buf+start, buf+start+skip,
3479 datal);
3480 }
3481
3482 leaf = path->nodes[0];
3483 slot = path->slots[0];
3484 write_extent_buffer(leaf, buf,
3485 btrfs_item_ptr_offset(leaf, slot),
3486 size);
3487 inode_add_bytes(inode, datal);
3488 }
3489
3490 /* If we have an implicit hole (NO_HOLES feature). */
3491 if (drop_start < new_key.offset)
3492 clone_update_extent_map(inode, trans,
3493 NULL, drop_start,
3494 new_key.offset - drop_start);
3495
3496 clone_update_extent_map(inode, trans, path, 0, 0);
3497
3498 btrfs_mark_buffer_dirty(leaf);
3499 btrfs_release_path(path);
3500
3501 last_dest_end = ALIGN(new_key.offset + datal,
3502 root->sectorsize);
3503 ret = clone_finish_inode_update(trans, inode,
3504 last_dest_end,
3505 destoff, olen);
3506 if (ret)
3507 goto out;
3508 if (new_key.offset + datal >= destoff + len)
3509 break;
3510 }
3511 btrfs_release_path(path);
3512 key.offset = next_key_min_offset;
3513 }
3514 ret = 0;
3515
3516 if (last_dest_end < destoff + len) {
3517 /*
3518 * We have an implicit hole (NO_HOLES feature is enabled) that
3519 * fully or partially overlaps our cloning range at its end.
3520 */
3521 btrfs_release_path(path);
3522
3523 /*
3524 * 1 - remove extent(s)
3525 * 1 - inode update
3526 */
3527 trans = btrfs_start_transaction(root, 2);
3528 if (IS_ERR(trans)) {
3529 ret = PTR_ERR(trans);
3530 goto out;
3531 }
3532 ret = btrfs_drop_extents(trans, root, inode,
3533 last_dest_end, destoff + len, 1);
3534 if (ret) {
3535 if (ret != -EOPNOTSUPP)
3536 btrfs_abort_transaction(trans, root, ret);
3537 btrfs_end_transaction(trans, root);
3538 goto out;
3539 }
3540 clone_update_extent_map(inode, trans, NULL, last_dest_end,
3541 destoff + len - last_dest_end);
3542 ret = clone_finish_inode_update(trans, inode, destoff + len,
3543 destoff, olen);
3544 }
3545
3546 out:
3547 btrfs_free_path(path);
3548 vfree(buf);
3549 return ret;
3550 }
3551
3552 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
3553 u64 off, u64 olen, u64 destoff)
3554 {
3555 struct inode *inode = file_inode(file);
3556 struct btrfs_root *root = BTRFS_I(inode)->root;
3557 struct fd src_file;
3558 struct inode *src;
3559 int ret;
3560 u64 len = olen;
3561 u64 bs = root->fs_info->sb->s_blocksize;
3562 int same_inode = 0;
3563
3564 /*
3565 * TODO:
3566 * - split compressed inline extents. annoying: we need to
3567 * decompress into destination's address_space (the file offset
3568 * may change, so source mapping won't do), then recompress (or
3569 * otherwise reinsert) a subrange.
3570 *
3571 * - split destination inode's inline extents. The inline extents can
3572 * be either compressed or non-compressed.
3573 */
3574
3575 /* the destination must be opened for writing */
3576 if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
3577 return -EINVAL;
3578
3579 if (btrfs_root_readonly(root))
3580 return -EROFS;
3581
3582 ret = mnt_want_write_file(file);
3583 if (ret)
3584 return ret;
3585
3586 src_file = fdget(srcfd);
3587 if (!src_file.file) {
3588 ret = -EBADF;
3589 goto out_drop_write;
3590 }
3591
3592 ret = -EXDEV;
3593 if (src_file.file->f_path.mnt != file->f_path.mnt)
3594 goto out_fput;
3595
3596 src = file_inode(src_file.file);
3597
3598 ret = -EINVAL;
3599 if (src == inode)
3600 same_inode = 1;
3601
3602 /* the src must be open for reading */
3603 if (!(src_file.file->f_mode & FMODE_READ))
3604 goto out_fput;
3605
3606 /* don't make the dst file partly checksummed */
3607 if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3608 (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3609 goto out_fput;
3610
3611 ret = -EISDIR;
3612 if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3613 goto out_fput;
3614
3615 ret = -EXDEV;
3616 if (src->i_sb != inode->i_sb)
3617 goto out_fput;
3618
3619 if (!same_inode) {
3620 if (inode < src) {
3621 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
3622 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
3623 } else {
3624 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
3625 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
3626 }
3627 } else {
3628 mutex_lock(&src->i_mutex);
3629 }
3630
3631 /* determine range to clone */
3632 ret = -EINVAL;
3633 if (off + len > src->i_size || off + len < off)
3634 goto out_unlock;
3635 if (len == 0)
3636 olen = len = src->i_size - off;
3637 /* if we extend to eof, continue to block boundary */
3638 if (off + len == src->i_size)
3639 len = ALIGN(src->i_size, bs) - off;
3640
3641 if (len == 0) {
3642 ret = 0;
3643 goto out_unlock;
3644 }
3645
3646 /* verify the end result is block aligned */
3647 if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
3648 !IS_ALIGNED(destoff, bs))
3649 goto out_unlock;
3650
3651 /* verify if ranges are overlapped within the same file */
3652 if (same_inode) {
3653 if (destoff + len > off && destoff < off + len)
3654 goto out_unlock;
3655 }
3656
3657 if (destoff > inode->i_size) {
3658 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3659 if (ret)
3660 goto out_unlock;
3661 }
3662
3663 /*
3664 * Lock the target range too. Right after we replace the file extent
3665 * items in the fs tree (which now point to the cloned data), we might
3666 * have a worker replace them with extent items relative to a write
3667 * operation that was issued before this clone operation (i.e. confront
3668 * with inode.c:btrfs_finish_ordered_io).
3669 */
3670 if (same_inode) {
3671 u64 lock_start = min_t(u64, off, destoff);
3672 u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
3673
3674 lock_extent_range(src, lock_start, lock_len);
3675 } else {
3676 lock_extent_range(src, off, len);
3677 lock_extent_range(inode, destoff, len);
3678 }
3679
3680 ret = btrfs_clone(src, inode, off, olen, len, destoff);
3681
3682 if (same_inode) {
3683 u64 lock_start = min_t(u64, off, destoff);
3684 u64 lock_end = max_t(u64, off, destoff) + len - 1;
3685
3686 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
3687 } else {
3688 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
3689 unlock_extent(&BTRFS_I(inode)->io_tree, destoff,
3690 destoff + len - 1);
3691 }
3692 /*
3693 * Truncate page cache pages so that future reads will see the cloned
3694 * data immediately and not the previous data.
3695 */
3696 truncate_inode_pages_range(&inode->i_data, destoff,
3697 PAGE_CACHE_ALIGN(destoff + len) - 1);
3698 out_unlock:
3699 if (!same_inode) {
3700 if (inode < src) {
3701 mutex_unlock(&src->i_mutex);
3702 mutex_unlock(&inode->i_mutex);
3703 } else {
3704 mutex_unlock(&inode->i_mutex);
3705 mutex_unlock(&src->i_mutex);
3706 }
3707 } else {
3708 mutex_unlock(&src->i_mutex);
3709 }
3710 out_fput:
3711 fdput(src_file);
3712 out_drop_write:
3713 mnt_drop_write_file(file);
3714 return ret;
3715 }
3716
3717 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3718 {
3719 struct btrfs_ioctl_clone_range_args args;
3720
3721 if (copy_from_user(&args, argp, sizeof(args)))
3722 return -EFAULT;
3723 return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
3724 args.src_length, args.dest_offset);
3725 }
3726
3727 /*
3728 * there are many ways the trans_start and trans_end ioctls can lead
3729 * to deadlocks. They should only be used by applications that
3730 * basically own the machine, and have a very in depth understanding
3731 * of all the possible deadlocks and enospc problems.
3732 */
3733 static long btrfs_ioctl_trans_start(struct file *file)
3734 {
3735 struct inode *inode = file_inode(file);
3736 struct btrfs_root *root = BTRFS_I(inode)->root;
3737 struct btrfs_trans_handle *trans;
3738 int ret;
3739
3740 ret = -EPERM;
3741 if (!capable(CAP_SYS_ADMIN))
3742 goto out;
3743
3744 ret = -EINPROGRESS;
3745 if (file->private_data)
3746 goto out;
3747
3748 ret = -EROFS;
3749 if (btrfs_root_readonly(root))
3750 goto out;
3751
3752 ret = mnt_want_write_file(file);
3753 if (ret)
3754 goto out;
3755
3756 atomic_inc(&root->fs_info->open_ioctl_trans);
3757
3758 ret = -ENOMEM;
3759 trans = btrfs_start_ioctl_transaction(root);
3760 if (IS_ERR(trans))
3761 goto out_drop;
3762
3763 file->private_data = trans;
3764 return 0;
3765
3766 out_drop:
3767 atomic_dec(&root->fs_info->open_ioctl_trans);
3768 mnt_drop_write_file(file);
3769 out:
3770 return ret;
3771 }
3772
3773 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3774 {
3775 struct inode *inode = file_inode(file);
3776 struct btrfs_root *root = BTRFS_I(inode)->root;
3777 struct btrfs_root *new_root;
3778 struct btrfs_dir_item *di;
3779 struct btrfs_trans_handle *trans;
3780 struct btrfs_path *path;
3781 struct btrfs_key location;
3782 struct btrfs_disk_key disk_key;
3783 u64 objectid = 0;
3784 u64 dir_id;
3785 int ret;
3786
3787 if (!capable(CAP_SYS_ADMIN))
3788 return -EPERM;
3789
3790 ret = mnt_want_write_file(file);
3791 if (ret)
3792 return ret;
3793
3794 if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3795 ret = -EFAULT;
3796 goto out;
3797 }
3798
3799 if (!objectid)
3800 objectid = BTRFS_FS_TREE_OBJECTID;
3801
3802 location.objectid = objectid;
3803 location.type = BTRFS_ROOT_ITEM_KEY;
3804 location.offset = (u64)-1;
3805
3806 new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
3807 if (IS_ERR(new_root)) {
3808 ret = PTR_ERR(new_root);
3809 goto out;
3810 }
3811
3812 path = btrfs_alloc_path();
3813 if (!path) {
3814 ret = -ENOMEM;
3815 goto out;
3816 }
3817 path->leave_spinning = 1;
3818
3819 trans = btrfs_start_transaction(root, 1);
3820 if (IS_ERR(trans)) {
3821 btrfs_free_path(path);
3822 ret = PTR_ERR(trans);
3823 goto out;
3824 }
3825
3826 dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3827 di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
3828 dir_id, "default", 7, 1);
3829 if (IS_ERR_OR_NULL(di)) {
3830 btrfs_free_path(path);
3831 btrfs_end_transaction(trans, root);
3832 btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
3833 "item, this isn't going to work");
3834 ret = -ENOENT;
3835 goto out;
3836 }
3837
3838 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3839 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3840 btrfs_mark_buffer_dirty(path->nodes[0]);
3841 btrfs_free_path(path);
3842
3843 btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
3844 btrfs_end_transaction(trans, root);
3845 out:
3846 mnt_drop_write_file(file);
3847 return ret;
3848 }
3849
3850 void btrfs_get_block_group_info(struct list_head *groups_list,
3851 struct btrfs_ioctl_space_info *space)
3852 {
3853 struct btrfs_block_group_cache *block_group;
3854
3855 space->total_bytes = 0;
3856 space->used_bytes = 0;
3857 space->flags = 0;
3858 list_for_each_entry(block_group, groups_list, list) {
3859 space->flags = block_group->flags;
3860 space->total_bytes += block_group->key.offset;
3861 space->used_bytes +=
3862 btrfs_block_group_used(&block_group->item);
3863 }
3864 }
3865
3866 static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
3867 {
3868 struct btrfs_ioctl_space_args space_args;
3869 struct btrfs_ioctl_space_info space;
3870 struct btrfs_ioctl_space_info *dest;
3871 struct btrfs_ioctl_space_info *dest_orig;
3872 struct btrfs_ioctl_space_info __user *user_dest;
3873 struct btrfs_space_info *info;
3874 u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3875 BTRFS_BLOCK_GROUP_SYSTEM,
3876 BTRFS_BLOCK_GROUP_METADATA,
3877 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3878 int num_types = 4;
3879 int alloc_size;
3880 int ret = 0;
3881 u64 slot_count = 0;
3882 int i, c;
3883
3884 if (copy_from_user(&space_args,
3885 (struct btrfs_ioctl_space_args __user *)arg,
3886 sizeof(space_args)))
3887 return -EFAULT;
3888
3889 for (i = 0; i < num_types; i++) {
3890 struct btrfs_space_info *tmp;
3891
3892 info = NULL;
3893 rcu_read_lock();
3894 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3895 list) {
3896 if (tmp->flags == types[i]) {
3897 info = tmp;
3898 break;
3899 }
3900 }
3901 rcu_read_unlock();
3902
3903 if (!info)
3904 continue;
3905
3906 down_read(&info->groups_sem);
3907 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3908 if (!list_empty(&info->block_groups[c]))
3909 slot_count++;
3910 }
3911 up_read(&info->groups_sem);
3912 }
3913
3914 /*
3915 * Global block reserve, exported as a space_info
3916 */
3917 slot_count++;
3918
3919 /* space_slots == 0 means they are asking for a count */
3920 if (space_args.space_slots == 0) {
3921 space_args.total_spaces = slot_count;
3922 goto out;
3923 }
3924
3925 slot_count = min_t(u64, space_args.space_slots, slot_count);
3926
3927 alloc_size = sizeof(*dest) * slot_count;
3928
3929 /* we generally have at most 6 or so space infos, one for each raid
3930 * level. So, a whole page should be more than enough for everyone
3931 */
3932 if (alloc_size > PAGE_CACHE_SIZE)
3933 return -ENOMEM;
3934
3935 space_args.total_spaces = 0;
3936 dest = kmalloc(alloc_size, GFP_NOFS);
3937 if (!dest)
3938 return -ENOMEM;
3939 dest_orig = dest;
3940
3941 /* now we have a buffer to copy into */
3942 for (i = 0; i < num_types; i++) {
3943 struct btrfs_space_info *tmp;
3944
3945 if (!slot_count)
3946 break;
3947
3948 info = NULL;
3949 rcu_read_lock();
3950 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3951 list) {
3952 if (tmp->flags == types[i]) {
3953 info = tmp;
3954 break;
3955 }
3956 }
3957 rcu_read_unlock();
3958
3959 if (!info)
3960 continue;
3961 down_read(&info->groups_sem);
3962 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3963 if (!list_empty(&info->block_groups[c])) {
3964 btrfs_get_block_group_info(
3965 &info->block_groups[c], &space);
3966 memcpy(dest, &space, sizeof(space));
3967 dest++;
3968 space_args.total_spaces++;
3969 slot_count--;
3970 }
3971 if (!slot_count)
3972 break;
3973 }
3974 up_read(&info->groups_sem);
3975 }
3976
3977 /*
3978 * Add global block reserve
3979 */
3980 if (slot_count) {
3981 struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv;
3982
3983 spin_lock(&block_rsv->lock);
3984 space.total_bytes = block_rsv->size;
3985 space.used_bytes = block_rsv->size - block_rsv->reserved;
3986 spin_unlock(&block_rsv->lock);
3987 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
3988 memcpy(dest, &space, sizeof(space));
3989 space_args.total_spaces++;
3990 }
3991
3992 user_dest = (struct btrfs_ioctl_space_info __user *)
3993 (arg + sizeof(struct btrfs_ioctl_space_args));
3994
3995 if (copy_to_user(user_dest, dest_orig, alloc_size))
3996 ret = -EFAULT;
3997
3998 kfree(dest_orig);
3999 out:
4000 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4001 ret = -EFAULT;
4002
4003 return ret;
4004 }
4005
4006 /*
4007 * there are many ways the trans_start and trans_end ioctls can lead
4008 * to deadlocks. They should only be used by applications that
4009 * basically own the machine, and have a very in depth understanding
4010 * of all the possible deadlocks and enospc problems.
4011 */
4012 long btrfs_ioctl_trans_end(struct file *file)
4013 {
4014 struct inode *inode = file_inode(file);
4015 struct btrfs_root *root = BTRFS_I(inode)->root;
4016 struct btrfs_trans_handle *trans;
4017
4018 trans = file->private_data;
4019 if (!trans)
4020 return -EINVAL;
4021 file->private_data = NULL;
4022
4023 btrfs_end_transaction(trans, root);
4024
4025 atomic_dec(&root->fs_info->open_ioctl_trans);
4026
4027 mnt_drop_write_file(file);
4028 return 0;
4029 }
4030
4031 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4032 void __user *argp)
4033 {
4034 struct btrfs_trans_handle *trans;
4035 u64 transid;
4036 int ret;
4037
4038 trans = btrfs_attach_transaction_barrier(root);
4039 if (IS_ERR(trans)) {
4040 if (PTR_ERR(trans) != -ENOENT)
4041 return PTR_ERR(trans);
4042
4043 /* No running transaction, don't bother */
4044 transid = root->fs_info->last_trans_committed;
4045 goto out;
4046 }
4047 transid = trans->transid;
4048 ret = btrfs_commit_transaction_async(trans, root, 0);
4049 if (ret) {
4050 btrfs_end_transaction(trans, root);
4051 return ret;
4052 }
4053 out:
4054 if (argp)
4055 if (copy_to_user(argp, &transid, sizeof(transid)))
4056 return -EFAULT;
4057 return 0;
4058 }
4059
4060 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
4061 void __user *argp)
4062 {
4063 u64 transid;
4064
4065 if (argp) {
4066 if (copy_from_user(&transid, argp, sizeof(transid)))
4067 return -EFAULT;
4068 } else {
4069 transid = 0; /* current trans */
4070 }
4071 return btrfs_wait_for_commit(root, transid);
4072 }
4073
4074 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4075 {
4076 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4077 struct btrfs_ioctl_scrub_args *sa;
4078 int ret;
4079
4080 if (!capable(CAP_SYS_ADMIN))
4081 return -EPERM;
4082
4083 sa = memdup_user(arg, sizeof(*sa));
4084 if (IS_ERR(sa))
4085 return PTR_ERR(sa);
4086
4087 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4088 ret = mnt_want_write_file(file);
4089 if (ret)
4090 goto out;
4091 }
4092
4093 ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
4094 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4095 0);
4096
4097 if (copy_to_user(arg, sa, sizeof(*sa)))
4098 ret = -EFAULT;
4099
4100 if (!(sa->flags & BTRFS_SCRUB_READONLY))
4101 mnt_drop_write_file(file);
4102 out:
4103 kfree(sa);
4104 return ret;
4105 }
4106
4107 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
4108 {
4109 if (!capable(CAP_SYS_ADMIN))
4110 return -EPERM;
4111
4112 return btrfs_scrub_cancel(root->fs_info);
4113 }
4114
4115 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
4116 void __user *arg)
4117 {
4118 struct btrfs_ioctl_scrub_args *sa;
4119 int ret;
4120
4121 if (!capable(CAP_SYS_ADMIN))
4122 return -EPERM;
4123
4124 sa = memdup_user(arg, sizeof(*sa));
4125 if (IS_ERR(sa))
4126 return PTR_ERR(sa);
4127
4128 ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
4129
4130 if (copy_to_user(arg, sa, sizeof(*sa)))
4131 ret = -EFAULT;
4132
4133 kfree(sa);
4134 return ret;
4135 }
4136
4137 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
4138 void __user *arg)
4139 {
4140 struct btrfs_ioctl_get_dev_stats *sa;
4141 int ret;
4142
4143 sa = memdup_user(arg, sizeof(*sa));
4144 if (IS_ERR(sa))
4145 return PTR_ERR(sa);
4146
4147 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4148 kfree(sa);
4149 return -EPERM;
4150 }
4151
4152 ret = btrfs_get_dev_stats(root, sa);
4153
4154 if (copy_to_user(arg, sa, sizeof(*sa)))
4155 ret = -EFAULT;
4156
4157 kfree(sa);
4158 return ret;
4159 }
4160
4161 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
4162 {
4163 struct btrfs_ioctl_dev_replace_args *p;
4164 int ret;
4165
4166 if (!capable(CAP_SYS_ADMIN))
4167 return -EPERM;
4168
4169 p = memdup_user(arg, sizeof(*p));
4170 if (IS_ERR(p))
4171 return PTR_ERR(p);
4172
4173 switch (p->cmd) {
4174 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4175 if (root->fs_info->sb->s_flags & MS_RDONLY) {
4176 ret = -EROFS;
4177 goto out;
4178 }
4179 if (atomic_xchg(
4180 &root->fs_info->mutually_exclusive_operation_running,
4181 1)) {
4182 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4183 } else {
4184 ret = btrfs_dev_replace_start(root, p);
4185 atomic_set(
4186 &root->fs_info->mutually_exclusive_operation_running,
4187 0);
4188 }
4189 break;
4190 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4191 btrfs_dev_replace_status(root->fs_info, p);
4192 ret = 0;
4193 break;
4194 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4195 ret = btrfs_dev_replace_cancel(root->fs_info, p);
4196 break;
4197 default:
4198 ret = -EINVAL;
4199 break;
4200 }
4201
4202 if (copy_to_user(arg, p, sizeof(*p)))
4203 ret = -EFAULT;
4204 out:
4205 kfree(p);
4206 return ret;
4207 }
4208
4209 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4210 {
4211 int ret = 0;
4212 int i;
4213 u64 rel_ptr;
4214 int size;
4215 struct btrfs_ioctl_ino_path_args *ipa = NULL;
4216 struct inode_fs_paths *ipath = NULL;
4217 struct btrfs_path *path;
4218
4219 if (!capable(CAP_DAC_READ_SEARCH))
4220 return -EPERM;
4221
4222 path = btrfs_alloc_path();
4223 if (!path) {
4224 ret = -ENOMEM;
4225 goto out;
4226 }
4227
4228 ipa = memdup_user(arg, sizeof(*ipa));
4229 if (IS_ERR(ipa)) {
4230 ret = PTR_ERR(ipa);
4231 ipa = NULL;
4232 goto out;
4233 }
4234
4235 size = min_t(u32, ipa->size, 4096);
4236 ipath = init_ipath(size, root, path);
4237 if (IS_ERR(ipath)) {
4238 ret = PTR_ERR(ipath);
4239 ipath = NULL;
4240 goto out;
4241 }
4242
4243 ret = paths_from_inode(ipa->inum, ipath);
4244 if (ret < 0)
4245 goto out;
4246
4247 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4248 rel_ptr = ipath->fspath->val[i] -
4249 (u64)(unsigned long)ipath->fspath->val;
4250 ipath->fspath->val[i] = rel_ptr;
4251 }
4252
4253 ret = copy_to_user((void *)(unsigned long)ipa->fspath,
4254 (void *)(unsigned long)ipath->fspath, size);
4255 if (ret) {
4256 ret = -EFAULT;
4257 goto out;
4258 }
4259
4260 out:
4261 btrfs_free_path(path);
4262 free_ipath(ipath);
4263 kfree(ipa);
4264
4265 return ret;
4266 }
4267
4268 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4269 {
4270 struct btrfs_data_container *inodes = ctx;
4271 const size_t c = 3 * sizeof(u64);
4272
4273 if (inodes->bytes_left >= c) {
4274 inodes->bytes_left -= c;
4275 inodes->val[inodes->elem_cnt] = inum;
4276 inodes->val[inodes->elem_cnt + 1] = offset;
4277 inodes->val[inodes->elem_cnt + 2] = root;
4278 inodes->elem_cnt += 3;
4279 } else {
4280 inodes->bytes_missing += c - inodes->bytes_left;
4281 inodes->bytes_left = 0;
4282 inodes->elem_missed += 3;
4283 }
4284
4285 return 0;
4286 }
4287
4288 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
4289 void __user *arg)
4290 {
4291 int ret = 0;
4292 int size;
4293 struct btrfs_ioctl_logical_ino_args *loi;
4294 struct btrfs_data_container *inodes = NULL;
4295 struct btrfs_path *path = NULL;
4296
4297 if (!capable(CAP_SYS_ADMIN))
4298 return -EPERM;
4299
4300 loi = memdup_user(arg, sizeof(*loi));
4301 if (IS_ERR(loi)) {
4302 ret = PTR_ERR(loi);
4303 loi = NULL;
4304 goto out;
4305 }
4306
4307 path = btrfs_alloc_path();
4308 if (!path) {
4309 ret = -ENOMEM;
4310 goto out;
4311 }
4312
4313 size = min_t(u32, loi->size, 64 * 1024);
4314 inodes = init_data_container(size);
4315 if (IS_ERR(inodes)) {
4316 ret = PTR_ERR(inodes);
4317 inodes = NULL;
4318 goto out;
4319 }
4320
4321 ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
4322 build_ino_list, inodes);
4323 if (ret == -EINVAL)
4324 ret = -ENOENT;
4325 if (ret < 0)
4326 goto out;
4327
4328 ret = copy_to_user((void *)(unsigned long)loi->inodes,
4329 (void *)(unsigned long)inodes, size);
4330 if (ret)
4331 ret = -EFAULT;
4332
4333 out:
4334 btrfs_free_path(path);
4335 vfree(inodes);
4336 kfree(loi);
4337
4338 return ret;
4339 }
4340
4341 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
4342 struct btrfs_ioctl_balance_args *bargs)
4343 {
4344 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4345
4346 bargs->flags = bctl->flags;
4347
4348 if (atomic_read(&fs_info->balance_running))
4349 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4350 if (atomic_read(&fs_info->balance_pause_req))
4351 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4352 if (atomic_read(&fs_info->balance_cancel_req))
4353 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4354
4355 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4356 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4357 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4358
4359 if (lock) {
4360 spin_lock(&fs_info->balance_lock);
4361 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4362 spin_unlock(&fs_info->balance_lock);
4363 } else {
4364 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4365 }
4366 }
4367
4368 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4369 {
4370 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4371 struct btrfs_fs_info *fs_info = root->fs_info;
4372 struct btrfs_ioctl_balance_args *bargs;
4373 struct btrfs_balance_control *bctl;
4374 bool need_unlock; /* for mut. excl. ops lock */
4375 int ret;
4376
4377 if (!capable(CAP_SYS_ADMIN))
4378 return -EPERM;
4379
4380 ret = mnt_want_write_file(file);
4381 if (ret)
4382 return ret;
4383
4384 again:
4385 if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
4386 mutex_lock(&fs_info->volume_mutex);
4387 mutex_lock(&fs_info->balance_mutex);
4388 need_unlock = true;
4389 goto locked;
4390 }
4391
4392 /*
4393 * mut. excl. ops lock is locked. Three possibilites:
4394 * (1) some other op is running
4395 * (2) balance is running
4396 * (3) balance is paused -- special case (think resume)
4397 */
4398 mutex_lock(&fs_info->balance_mutex);
4399 if (fs_info->balance_ctl) {
4400 /* this is either (2) or (3) */
4401 if (!atomic_read(&fs_info->balance_running)) {
4402 mutex_unlock(&fs_info->balance_mutex);
4403 if (!mutex_trylock(&fs_info->volume_mutex))
4404 goto again;
4405 mutex_lock(&fs_info->balance_mutex);
4406
4407 if (fs_info->balance_ctl &&
4408 !atomic_read(&fs_info->balance_running)) {
4409 /* this is (3) */
4410 need_unlock = false;
4411 goto locked;
4412 }
4413
4414 mutex_unlock(&fs_info->balance_mutex);
4415 mutex_unlock(&fs_info->volume_mutex);
4416 goto again;
4417 } else {
4418 /* this is (2) */
4419 mutex_unlock(&fs_info->balance_mutex);
4420 ret = -EINPROGRESS;
4421 goto out;
4422 }
4423 } else {
4424 /* this is (1) */
4425 mutex_unlock(&fs_info->balance_mutex);
4426 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4427 goto out;
4428 }
4429
4430 locked:
4431 BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4432
4433 if (arg) {
4434 bargs = memdup_user(arg, sizeof(*bargs));
4435 if (IS_ERR(bargs)) {
4436 ret = PTR_ERR(bargs);
4437 goto out_unlock;
4438 }
4439
4440 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4441 if (!fs_info->balance_ctl) {
4442 ret = -ENOTCONN;
4443 goto out_bargs;
4444 }
4445
4446 bctl = fs_info->balance_ctl;
4447 spin_lock(&fs_info->balance_lock);
4448 bctl->flags |= BTRFS_BALANCE_RESUME;
4449 spin_unlock(&fs_info->balance_lock);
4450
4451 goto do_balance;
4452 }
4453 } else {
4454 bargs = NULL;
4455 }
4456
4457 if (fs_info->balance_ctl) {
4458 ret = -EINPROGRESS;
4459 goto out_bargs;
4460 }
4461
4462 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
4463 if (!bctl) {
4464 ret = -ENOMEM;
4465 goto out_bargs;
4466 }
4467
4468 bctl->fs_info = fs_info;
4469 if (arg) {
4470 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4471 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4472 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4473
4474 bctl->flags = bargs->flags;
4475 } else {
4476 /* balance everything - no filters */
4477 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4478 }
4479
4480 do_balance:
4481 /*
4482 * Ownership of bctl and mutually_exclusive_operation_running
4483 * goes to to btrfs_balance. bctl is freed in __cancel_balance,
4484 * or, if restriper was paused all the way until unmount, in
4485 * free_fs_info. mutually_exclusive_operation_running is
4486 * cleared in __cancel_balance.
4487 */
4488 need_unlock = false;
4489
4490 ret = btrfs_balance(bctl, bargs);
4491
4492 if (arg) {
4493 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4494 ret = -EFAULT;
4495 }
4496
4497 out_bargs:
4498 kfree(bargs);
4499 out_unlock:
4500 mutex_unlock(&fs_info->balance_mutex);
4501 mutex_unlock(&fs_info->volume_mutex);
4502 if (need_unlock)
4503 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
4504 out:
4505 mnt_drop_write_file(file);
4506 return ret;
4507 }
4508
4509 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
4510 {
4511 if (!capable(CAP_SYS_ADMIN))
4512 return -EPERM;
4513
4514 switch (cmd) {
4515 case BTRFS_BALANCE_CTL_PAUSE:
4516 return btrfs_pause_balance(root->fs_info);
4517 case BTRFS_BALANCE_CTL_CANCEL:
4518 return btrfs_cancel_balance(root->fs_info);
4519 }
4520
4521 return -EINVAL;
4522 }
4523
4524 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
4525 void __user *arg)
4526 {
4527 struct btrfs_fs_info *fs_info = root->fs_info;
4528 struct btrfs_ioctl_balance_args *bargs;
4529 int ret = 0;
4530
4531 if (!capable(CAP_SYS_ADMIN))
4532 return -EPERM;
4533
4534 mutex_lock(&fs_info->balance_mutex);
4535 if (!fs_info->balance_ctl) {
4536 ret = -ENOTCONN;
4537 goto out;
4538 }
4539
4540 bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
4541 if (!bargs) {
4542 ret = -ENOMEM;
4543 goto out;
4544 }
4545
4546 update_ioctl_balance_args(fs_info, 1, bargs);
4547
4548 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4549 ret = -EFAULT;
4550
4551 kfree(bargs);
4552 out:
4553 mutex_unlock(&fs_info->balance_mutex);
4554 return ret;
4555 }
4556
4557 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4558 {
4559 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4560 struct btrfs_ioctl_quota_ctl_args *sa;
4561 struct btrfs_trans_handle *trans = NULL;
4562 int ret;
4563 int err;
4564
4565 if (!capable(CAP_SYS_ADMIN))
4566 return -EPERM;
4567
4568 ret = mnt_want_write_file(file);
4569 if (ret)
4570 return ret;
4571
4572 sa = memdup_user(arg, sizeof(*sa));
4573 if (IS_ERR(sa)) {
4574 ret = PTR_ERR(sa);
4575 goto drop_write;
4576 }
4577
4578 down_write(&root->fs_info->subvol_sem);
4579 trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
4580 if (IS_ERR(trans)) {
4581 ret = PTR_ERR(trans);
4582 goto out;
4583 }
4584
4585 switch (sa->cmd) {
4586 case BTRFS_QUOTA_CTL_ENABLE:
4587 ret = btrfs_quota_enable(trans, root->fs_info);
4588 break;
4589 case BTRFS_QUOTA_CTL_DISABLE:
4590 ret = btrfs_quota_disable(trans, root->fs_info);
4591 break;
4592 default:
4593 ret = -EINVAL;
4594 break;
4595 }
4596
4597 err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
4598 if (err && !ret)
4599 ret = err;
4600 out:
4601 kfree(sa);
4602 up_write(&root->fs_info->subvol_sem);
4603 drop_write:
4604 mnt_drop_write_file(file);
4605 return ret;
4606 }
4607
4608 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4609 {
4610 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4611 struct btrfs_ioctl_qgroup_assign_args *sa;
4612 struct btrfs_trans_handle *trans;
4613 int ret;
4614 int err;
4615
4616 if (!capable(CAP_SYS_ADMIN))
4617 return -EPERM;
4618
4619 ret = mnt_want_write_file(file);
4620 if (ret)
4621 return ret;
4622
4623 sa = memdup_user(arg, sizeof(*sa));
4624 if (IS_ERR(sa)) {
4625 ret = PTR_ERR(sa);
4626 goto drop_write;
4627 }
4628
4629 trans = btrfs_join_transaction(root);
4630 if (IS_ERR(trans)) {
4631 ret = PTR_ERR(trans);
4632 goto out;
4633 }
4634
4635 /* FIXME: check if the IDs really exist */
4636 if (sa->assign) {
4637 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
4638 sa->src, sa->dst);
4639 } else {
4640 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
4641 sa->src, sa->dst);
4642 }
4643
4644 /* update qgroup status and info */
4645 err = btrfs_run_qgroups(trans, root->fs_info);
4646 if (err < 0)
4647 btrfs_error(root->fs_info, ret,
4648 "failed to update qgroup status and info\n");
4649 err = btrfs_end_transaction(trans, root);
4650 if (err && !ret)
4651 ret = err;
4652
4653 out:
4654 kfree(sa);
4655 drop_write:
4656 mnt_drop_write_file(file);
4657 return ret;
4658 }
4659
4660 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4661 {
4662 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4663 struct btrfs_ioctl_qgroup_create_args *sa;
4664 struct btrfs_trans_handle *trans;
4665 int ret;
4666 int err;
4667
4668 if (!capable(CAP_SYS_ADMIN))
4669 return -EPERM;
4670
4671 ret = mnt_want_write_file(file);
4672 if (ret)
4673 return ret;
4674
4675 sa = memdup_user(arg, sizeof(*sa));
4676 if (IS_ERR(sa)) {
4677 ret = PTR_ERR(sa);
4678 goto drop_write;
4679 }
4680
4681 if (!sa->qgroupid) {
4682 ret = -EINVAL;
4683 goto out;
4684 }
4685
4686 trans = btrfs_join_transaction(root);
4687 if (IS_ERR(trans)) {
4688 ret = PTR_ERR(trans);
4689 goto out;
4690 }
4691
4692 /* FIXME: check if the IDs really exist */
4693 if (sa->create) {
4694 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid);
4695 } else {
4696 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
4697 }
4698
4699 err = btrfs_end_transaction(trans, root);
4700 if (err && !ret)
4701 ret = err;
4702
4703 out:
4704 kfree(sa);
4705 drop_write:
4706 mnt_drop_write_file(file);
4707 return ret;
4708 }
4709
4710 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4711 {
4712 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4713 struct btrfs_ioctl_qgroup_limit_args *sa;
4714 struct btrfs_trans_handle *trans;
4715 int ret;
4716 int err;
4717 u64 qgroupid;
4718
4719 if (!capable(CAP_SYS_ADMIN))
4720 return -EPERM;
4721
4722 ret = mnt_want_write_file(file);
4723 if (ret)
4724 return ret;
4725
4726 sa = memdup_user(arg, sizeof(*sa));
4727 if (IS_ERR(sa)) {
4728 ret = PTR_ERR(sa);
4729 goto drop_write;
4730 }
4731
4732 trans = btrfs_join_transaction(root);
4733 if (IS_ERR(trans)) {
4734 ret = PTR_ERR(trans);
4735 goto out;
4736 }
4737
4738 qgroupid = sa->qgroupid;
4739 if (!qgroupid) {
4740 /* take the current subvol as qgroup */
4741 qgroupid = root->root_key.objectid;
4742 }
4743
4744 /* FIXME: check if the IDs really exist */
4745 ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
4746
4747 err = btrfs_end_transaction(trans, root);
4748 if (err && !ret)
4749 ret = err;
4750
4751 out:
4752 kfree(sa);
4753 drop_write:
4754 mnt_drop_write_file(file);
4755 return ret;
4756 }
4757
4758 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4759 {
4760 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4761 struct btrfs_ioctl_quota_rescan_args *qsa;
4762 int ret;
4763
4764 if (!capable(CAP_SYS_ADMIN))
4765 return -EPERM;
4766
4767 ret = mnt_want_write_file(file);
4768 if (ret)
4769 return ret;
4770
4771 qsa = memdup_user(arg, sizeof(*qsa));
4772 if (IS_ERR(qsa)) {
4773 ret = PTR_ERR(qsa);
4774 goto drop_write;
4775 }
4776
4777 if (qsa->flags) {
4778 ret = -EINVAL;
4779 goto out;
4780 }
4781
4782 ret = btrfs_qgroup_rescan(root->fs_info);
4783
4784 out:
4785 kfree(qsa);
4786 drop_write:
4787 mnt_drop_write_file(file);
4788 return ret;
4789 }
4790
4791 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
4792 {
4793 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4794 struct btrfs_ioctl_quota_rescan_args *qsa;
4795 int ret = 0;
4796
4797 if (!capable(CAP_SYS_ADMIN))
4798 return -EPERM;
4799
4800 qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
4801 if (!qsa)
4802 return -ENOMEM;
4803
4804 if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4805 qsa->flags = 1;
4806 qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
4807 }
4808
4809 if (copy_to_user(arg, qsa, sizeof(*qsa)))
4810 ret = -EFAULT;
4811
4812 kfree(qsa);
4813 return ret;
4814 }
4815
4816 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
4817 {
4818 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4819
4820 if (!capable(CAP_SYS_ADMIN))
4821 return -EPERM;
4822
4823 return btrfs_qgroup_wait_for_completion(root->fs_info);
4824 }
4825
4826 static long _btrfs_ioctl_set_received_subvol(struct file *file,
4827 struct btrfs_ioctl_received_subvol_args *sa)
4828 {
4829 struct inode *inode = file_inode(file);
4830 struct btrfs_root *root = BTRFS_I(inode)->root;
4831 struct btrfs_root_item *root_item = &root->root_item;
4832 struct btrfs_trans_handle *trans;
4833 struct timespec ct = CURRENT_TIME;
4834 int ret = 0;
4835 int received_uuid_changed;
4836
4837 if (!inode_owner_or_capable(inode))
4838 return -EPERM;
4839
4840 ret = mnt_want_write_file(file);
4841 if (ret < 0)
4842 return ret;
4843
4844 down_write(&root->fs_info->subvol_sem);
4845
4846 if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
4847 ret = -EINVAL;
4848 goto out;
4849 }
4850
4851 if (btrfs_root_readonly(root)) {
4852 ret = -EROFS;
4853 goto out;
4854 }
4855
4856 /*
4857 * 1 - root item
4858 * 2 - uuid items (received uuid + subvol uuid)
4859 */
4860 trans = btrfs_start_transaction(root, 3);
4861 if (IS_ERR(trans)) {
4862 ret = PTR_ERR(trans);
4863 trans = NULL;
4864 goto out;
4865 }
4866
4867 sa->rtransid = trans->transid;
4868 sa->rtime.sec = ct.tv_sec;
4869 sa->rtime.nsec = ct.tv_nsec;
4870
4871 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4872 BTRFS_UUID_SIZE);
4873 if (received_uuid_changed &&
4874 !btrfs_is_empty_uuid(root_item->received_uuid))
4875 btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
4876 root_item->received_uuid,
4877 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4878 root->root_key.objectid);
4879 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4880 btrfs_set_root_stransid(root_item, sa->stransid);
4881 btrfs_set_root_rtransid(root_item, sa->rtransid);
4882 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4883 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4884 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4885 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4886
4887 ret = btrfs_update_root(trans, root->fs_info->tree_root,
4888 &root->root_key, &root->root_item);
4889 if (ret < 0) {
4890 btrfs_end_transaction(trans, root);
4891 goto out;
4892 }
4893 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4894 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
4895 sa->uuid,
4896 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4897 root->root_key.objectid);
4898 if (ret < 0 && ret != -EEXIST) {
4899 btrfs_abort_transaction(trans, root, ret);
4900 goto out;
4901 }
4902 }
4903 ret = btrfs_commit_transaction(trans, root);
4904 if (ret < 0) {
4905 btrfs_abort_transaction(trans, root, ret);
4906 goto out;
4907 }
4908
4909 out:
4910 up_write(&root->fs_info->subvol_sem);
4911 mnt_drop_write_file(file);
4912 return ret;
4913 }
4914
4915 #ifdef CONFIG_64BIT
4916 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4917 void __user *arg)
4918 {
4919 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4920 struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4921 int ret = 0;
4922
4923 args32 = memdup_user(arg, sizeof(*args32));
4924 if (IS_ERR(args32)) {
4925 ret = PTR_ERR(args32);
4926 args32 = NULL;
4927 goto out;
4928 }
4929
4930 args64 = kmalloc(sizeof(*args64), GFP_NOFS);
4931 if (!args64) {
4932 ret = -ENOMEM;
4933 goto out;
4934 }
4935
4936 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4937 args64->stransid = args32->stransid;
4938 args64->rtransid = args32->rtransid;
4939 args64->stime.sec = args32->stime.sec;
4940 args64->stime.nsec = args32->stime.nsec;
4941 args64->rtime.sec = args32->rtime.sec;
4942 args64->rtime.nsec = args32->rtime.nsec;
4943 args64->flags = args32->flags;
4944
4945 ret = _btrfs_ioctl_set_received_subvol(file, args64);
4946 if (ret)
4947 goto out;
4948
4949 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4950 args32->stransid = args64->stransid;
4951 args32->rtransid = args64->rtransid;
4952 args32->stime.sec = args64->stime.sec;
4953 args32->stime.nsec = args64->stime.nsec;
4954 args32->rtime.sec = args64->rtime.sec;
4955 args32->rtime.nsec = args64->rtime.nsec;
4956 args32->flags = args64->flags;
4957
4958 ret = copy_to_user(arg, args32, sizeof(*args32));
4959 if (ret)
4960 ret = -EFAULT;
4961
4962 out:
4963 kfree(args32);
4964 kfree(args64);
4965 return ret;
4966 }
4967 #endif
4968
4969 static long btrfs_ioctl_set_received_subvol(struct file *file,
4970 void __user *arg)
4971 {
4972 struct btrfs_ioctl_received_subvol_args *sa = NULL;
4973 int ret = 0;
4974
4975 sa = memdup_user(arg, sizeof(*sa));
4976 if (IS_ERR(sa)) {
4977 ret = PTR_ERR(sa);
4978 sa = NULL;
4979 goto out;
4980 }
4981
4982 ret = _btrfs_ioctl_set_received_subvol(file, sa);
4983
4984 if (ret)
4985 goto out;
4986
4987 ret = copy_to_user(arg, sa, sizeof(*sa));
4988 if (ret)
4989 ret = -EFAULT;
4990
4991 out:
4992 kfree(sa);
4993 return ret;
4994 }
4995
4996 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
4997 {
4998 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4999 size_t len;
5000 int ret;
5001 char label[BTRFS_LABEL_SIZE];
5002
5003 spin_lock(&root->fs_info->super_lock);
5004 memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5005 spin_unlock(&root->fs_info->super_lock);
5006
5007 len = strnlen(label, BTRFS_LABEL_SIZE);
5008
5009 if (len == BTRFS_LABEL_SIZE) {
5010 btrfs_warn(root->fs_info,
5011 "label is too long, return the first %zu bytes", --len);
5012 }
5013
5014 ret = copy_to_user(arg, label, len);
5015
5016 return ret ? -EFAULT : 0;
5017 }
5018
5019 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5020 {
5021 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5022 struct btrfs_super_block *super_block = root->fs_info->super_copy;
5023 struct btrfs_trans_handle *trans;
5024 char label[BTRFS_LABEL_SIZE];
5025 int ret;
5026
5027 if (!capable(CAP_SYS_ADMIN))
5028 return -EPERM;
5029
5030 if (copy_from_user(label, arg, sizeof(label)))
5031 return -EFAULT;
5032
5033 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5034 btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
5035 BTRFS_LABEL_SIZE - 1);
5036 return -EINVAL;
5037 }
5038
5039 ret = mnt_want_write_file(file);
5040 if (ret)
5041 return ret;
5042
5043 trans = btrfs_start_transaction(root, 0);
5044 if (IS_ERR(trans)) {
5045 ret = PTR_ERR(trans);
5046 goto out_unlock;
5047 }
5048
5049 spin_lock(&root->fs_info->super_lock);
5050 strcpy(super_block->label, label);
5051 spin_unlock(&root->fs_info->super_lock);
5052 ret = btrfs_commit_transaction(trans, root);
5053
5054 out_unlock:
5055 mnt_drop_write_file(file);
5056 return ret;
5057 }
5058
5059 #define INIT_FEATURE_FLAGS(suffix) \
5060 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5061 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5062 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5063
5064 static int btrfs_ioctl_get_supported_features(struct file *file,
5065 void __user *arg)
5066 {
5067 static struct btrfs_ioctl_feature_flags features[3] = {
5068 INIT_FEATURE_FLAGS(SUPP),
5069 INIT_FEATURE_FLAGS(SAFE_SET),
5070 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5071 };
5072
5073 if (copy_to_user(arg, &features, sizeof(features)))
5074 return -EFAULT;
5075
5076 return 0;
5077 }
5078
5079 static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5080 {
5081 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5082 struct btrfs_super_block *super_block = root->fs_info->super_copy;
5083 struct btrfs_ioctl_feature_flags features;
5084
5085 features.compat_flags = btrfs_super_compat_flags(super_block);
5086 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5087 features.incompat_flags = btrfs_super_incompat_flags(super_block);
5088
5089 if (copy_to_user(arg, &features, sizeof(features)))
5090 return -EFAULT;
5091
5092 return 0;
5093 }
5094
5095 static int check_feature_bits(struct btrfs_root *root,
5096 enum btrfs_feature_set set,
5097 u64 change_mask, u64 flags, u64 supported_flags,
5098 u64 safe_set, u64 safe_clear)
5099 {
5100 const char *type = btrfs_feature_set_names[set];
5101 char *names;
5102 u64 disallowed, unsupported;
5103 u64 set_mask = flags & change_mask;
5104 u64 clear_mask = ~flags & change_mask;
5105
5106 unsupported = set_mask & ~supported_flags;
5107 if (unsupported) {
5108 names = btrfs_printable_features(set, unsupported);
5109 if (names) {
5110 btrfs_warn(root->fs_info,
5111 "this kernel does not support the %s feature bit%s",
5112 names, strchr(names, ',') ? "s" : "");
5113 kfree(names);
5114 } else
5115 btrfs_warn(root->fs_info,
5116 "this kernel does not support %s bits 0x%llx",
5117 type, unsupported);
5118 return -EOPNOTSUPP;
5119 }
5120
5121 disallowed = set_mask & ~safe_set;
5122 if (disallowed) {
5123 names = btrfs_printable_features(set, disallowed);
5124 if (names) {
5125 btrfs_warn(root->fs_info,
5126 "can't set the %s feature bit%s while mounted",
5127 names, strchr(names, ',') ? "s" : "");
5128 kfree(names);
5129 } else
5130 btrfs_warn(root->fs_info,
5131 "can't set %s bits 0x%llx while mounted",
5132 type, disallowed);
5133 return -EPERM;
5134 }
5135
5136 disallowed = clear_mask & ~safe_clear;
5137 if (disallowed) {
5138 names = btrfs_printable_features(set, disallowed);
5139 if (names) {
5140 btrfs_warn(root->fs_info,
5141 "can't clear the %s feature bit%s while mounted",
5142 names, strchr(names, ',') ? "s" : "");
5143 kfree(names);
5144 } else
5145 btrfs_warn(root->fs_info,
5146 "can't clear %s bits 0x%llx while mounted",
5147 type, disallowed);
5148 return -EPERM;
5149 }
5150
5151 return 0;
5152 }
5153
5154 #define check_feature(root, change_mask, flags, mask_base) \
5155 check_feature_bits(root, FEAT_##mask_base, change_mask, flags, \
5156 BTRFS_FEATURE_ ## mask_base ## _SUPP, \
5157 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \
5158 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5159
5160 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5161 {
5162 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5163 struct btrfs_super_block *super_block = root->fs_info->super_copy;
5164 struct btrfs_ioctl_feature_flags flags[2];
5165 struct btrfs_trans_handle *trans;
5166 u64 newflags;
5167 int ret;
5168
5169 if (!capable(CAP_SYS_ADMIN))
5170 return -EPERM;
5171
5172 if (copy_from_user(flags, arg, sizeof(flags)))
5173 return -EFAULT;
5174
5175 /* Nothing to do */
5176 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5177 !flags[0].incompat_flags)
5178 return 0;
5179
5180 ret = check_feature(root, flags[0].compat_flags,
5181 flags[1].compat_flags, COMPAT);
5182 if (ret)
5183 return ret;
5184
5185 ret = check_feature(root, flags[0].compat_ro_flags,
5186 flags[1].compat_ro_flags, COMPAT_RO);
5187 if (ret)
5188 return ret;
5189
5190 ret = check_feature(root, flags[0].incompat_flags,
5191 flags[1].incompat_flags, INCOMPAT);
5192 if (ret)
5193 return ret;
5194
5195 trans = btrfs_start_transaction(root, 0);
5196 if (IS_ERR(trans))
5197 return PTR_ERR(trans);
5198
5199 spin_lock(&root->fs_info->super_lock);
5200 newflags = btrfs_super_compat_flags(super_block);
5201 newflags |= flags[0].compat_flags & flags[1].compat_flags;
5202 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5203 btrfs_set_super_compat_flags(super_block, newflags);
5204
5205 newflags = btrfs_super_compat_ro_flags(super_block);
5206 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5207 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5208 btrfs_set_super_compat_ro_flags(super_block, newflags);
5209
5210 newflags = btrfs_super_incompat_flags(super_block);
5211 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5212 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5213 btrfs_set_super_incompat_flags(super_block, newflags);
5214 spin_unlock(&root->fs_info->super_lock);
5215
5216 return btrfs_commit_transaction(trans, root);
5217 }
5218
5219 long btrfs_ioctl(struct file *file, unsigned int
5220 cmd, unsigned long arg)
5221 {
5222 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5223 void __user *argp = (void __user *)arg;
5224
5225 switch (cmd) {
5226 case FS_IOC_GETFLAGS:
5227 return btrfs_ioctl_getflags(file, argp);
5228 case FS_IOC_SETFLAGS:
5229 return btrfs_ioctl_setflags(file, argp);
5230 case FS_IOC_GETVERSION:
5231 return btrfs_ioctl_getversion(file, argp);
5232 case FITRIM:
5233 return btrfs_ioctl_fitrim(file, argp);
5234 case BTRFS_IOC_SNAP_CREATE:
5235 return btrfs_ioctl_snap_create(file, argp, 0);
5236 case BTRFS_IOC_SNAP_CREATE_V2:
5237 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5238 case BTRFS_IOC_SUBVOL_CREATE:
5239 return btrfs_ioctl_snap_create(file, argp, 1);
5240 case BTRFS_IOC_SUBVOL_CREATE_V2:
5241 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5242 case BTRFS_IOC_SNAP_DESTROY:
5243 return btrfs_ioctl_snap_destroy(file, argp);
5244 case BTRFS_IOC_SUBVOL_GETFLAGS:
5245 return btrfs_ioctl_subvol_getflags(file, argp);
5246 case BTRFS_IOC_SUBVOL_SETFLAGS:
5247 return btrfs_ioctl_subvol_setflags(file, argp);
5248 case BTRFS_IOC_DEFAULT_SUBVOL:
5249 return btrfs_ioctl_default_subvol(file, argp);
5250 case BTRFS_IOC_DEFRAG:
5251 return btrfs_ioctl_defrag(file, NULL);
5252 case BTRFS_IOC_DEFRAG_RANGE:
5253 return btrfs_ioctl_defrag(file, argp);
5254 case BTRFS_IOC_RESIZE:
5255 return btrfs_ioctl_resize(file, argp);
5256 case BTRFS_IOC_ADD_DEV:
5257 return btrfs_ioctl_add_dev(root, argp);
5258 case BTRFS_IOC_RM_DEV:
5259 return btrfs_ioctl_rm_dev(file, argp);
5260 case BTRFS_IOC_FS_INFO:
5261 return btrfs_ioctl_fs_info(root, argp);
5262 case BTRFS_IOC_DEV_INFO:
5263 return btrfs_ioctl_dev_info(root, argp);
5264 case BTRFS_IOC_BALANCE:
5265 return btrfs_ioctl_balance(file, NULL);
5266 case BTRFS_IOC_CLONE:
5267 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
5268 case BTRFS_IOC_CLONE_RANGE:
5269 return btrfs_ioctl_clone_range(file, argp);
5270 case BTRFS_IOC_TRANS_START:
5271 return btrfs_ioctl_trans_start(file);
5272 case BTRFS_IOC_TRANS_END:
5273 return btrfs_ioctl_trans_end(file);
5274 case BTRFS_IOC_TREE_SEARCH:
5275 return btrfs_ioctl_tree_search(file, argp);
5276 case BTRFS_IOC_TREE_SEARCH_V2:
5277 return btrfs_ioctl_tree_search_v2(file, argp);
5278 case BTRFS_IOC_INO_LOOKUP:
5279 return btrfs_ioctl_ino_lookup(file, argp);
5280 case BTRFS_IOC_INO_PATHS:
5281 return btrfs_ioctl_ino_to_path(root, argp);
5282 case BTRFS_IOC_LOGICAL_INO:
5283 return btrfs_ioctl_logical_to_ino(root, argp);
5284 case BTRFS_IOC_SPACE_INFO:
5285 return btrfs_ioctl_space_info(root, argp);
5286 case BTRFS_IOC_SYNC: {
5287 int ret;
5288
5289 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
5290 if (ret)
5291 return ret;
5292 ret = btrfs_sync_fs(file_inode(file)->i_sb, 1);
5293 /*
5294 * The transaction thread may want to do more work,
5295 * namely it pokes the cleaner ktread that will start
5296 * processing uncleaned subvols.
5297 */
5298 wake_up_process(root->fs_info->transaction_kthread);
5299 return ret;
5300 }
5301 case BTRFS_IOC_START_SYNC:
5302 return btrfs_ioctl_start_sync(root, argp);
5303 case BTRFS_IOC_WAIT_SYNC:
5304 return btrfs_ioctl_wait_sync(root, argp);
5305 case BTRFS_IOC_SCRUB:
5306 return btrfs_ioctl_scrub(file, argp);
5307 case BTRFS_IOC_SCRUB_CANCEL:
5308 return btrfs_ioctl_scrub_cancel(root, argp);
5309 case BTRFS_IOC_SCRUB_PROGRESS:
5310 return btrfs_ioctl_scrub_progress(root, argp);
5311 case BTRFS_IOC_BALANCE_V2:
5312 return btrfs_ioctl_balance(file, argp);
5313 case BTRFS_IOC_BALANCE_CTL:
5314 return btrfs_ioctl_balance_ctl(root, arg);
5315 case BTRFS_IOC_BALANCE_PROGRESS:
5316 return btrfs_ioctl_balance_progress(root, argp);
5317 case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5318 return btrfs_ioctl_set_received_subvol(file, argp);
5319 #ifdef CONFIG_64BIT
5320 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5321 return btrfs_ioctl_set_received_subvol_32(file, argp);
5322 #endif
5323 case BTRFS_IOC_SEND:
5324 return btrfs_ioctl_send(file, argp);
5325 case BTRFS_IOC_GET_DEV_STATS:
5326 return btrfs_ioctl_get_dev_stats(root, argp);
5327 case BTRFS_IOC_QUOTA_CTL:
5328 return btrfs_ioctl_quota_ctl(file, argp);
5329 case BTRFS_IOC_QGROUP_ASSIGN:
5330 return btrfs_ioctl_qgroup_assign(file, argp);
5331 case BTRFS_IOC_QGROUP_CREATE:
5332 return btrfs_ioctl_qgroup_create(file, argp);
5333 case BTRFS_IOC_QGROUP_LIMIT:
5334 return btrfs_ioctl_qgroup_limit(file, argp);
5335 case BTRFS_IOC_QUOTA_RESCAN:
5336 return btrfs_ioctl_quota_rescan(file, argp);
5337 case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5338 return btrfs_ioctl_quota_rescan_status(file, argp);
5339 case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5340 return btrfs_ioctl_quota_rescan_wait(file, argp);
5341 case BTRFS_IOC_DEV_REPLACE:
5342 return btrfs_ioctl_dev_replace(root, argp);
5343 case BTRFS_IOC_GET_FSLABEL:
5344 return btrfs_ioctl_get_fslabel(file, argp);
5345 case BTRFS_IOC_SET_FSLABEL:
5346 return btrfs_ioctl_set_fslabel(file, argp);
5347 case BTRFS_IOC_FILE_EXTENT_SAME:
5348 return btrfs_ioctl_file_extent_same(file, argp);
5349 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5350 return btrfs_ioctl_get_supported_features(file, argp);
5351 case BTRFS_IOC_GET_FEATURES:
5352 return btrfs_ioctl_get_features(file, argp);
5353 case BTRFS_IOC_SET_FEATURES:
5354 return btrfs_ioctl_set_features(file, argp);
5355 }
5356
5357 return -ENOTTY;
5358 }
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