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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/smp_lock.h> | |
31 | #include <linux/backing-dev.h> | |
32 | #include <linux/mount.h> | |
33 | #include <linux/mpage.h> | |
34 | #include <linux/namei.h> | |
35 | #include <linux/swap.h> | |
36 | #include <linux/writeback.h> | |
37 | #include <linux/statfs.h> | |
38 | #include <linux/compat.h> | |
39 | #include <linux/bit_spinlock.h> | |
40 | #include <linux/security.h> | |
41 | #include <linux/xattr.h> | |
42 | #include <linux/vmalloc.h> | |
43 | #include "compat.h" | |
44 | #include "ctree.h" | |
45 | #include "disk-io.h" | |
46 | #include "transaction.h" | |
47 | #include "btrfs_inode.h" | |
48 | #include "ioctl.h" | |
49 | #include "print-tree.h" | |
50 | #include "volumes.h" | |
51 | #include "locking.h" | |
52 | ||
53 | ||
54 | ||
55 | static noinline int create_subvol(struct btrfs_root *root, | |
56 | struct dentry *dentry, | |
57 | char *name, int namelen) | |
58 | { | |
59 | struct btrfs_trans_handle *trans; | |
60 | struct btrfs_key key; | |
61 | struct btrfs_root_item root_item; | |
62 | struct btrfs_inode_item *inode_item; | |
63 | struct extent_buffer *leaf; | |
64 | struct btrfs_root *new_root = root; | |
65 | struct inode *dir; | |
66 | int ret; | |
67 | int err; | |
68 | u64 objectid; | |
69 | u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID; | |
70 | u64 index = 0; | |
71 | unsigned long nr = 1; | |
72 | ||
73 | ret = btrfs_check_metadata_free_space(root); | |
74 | if (ret) | |
75 | goto fail_commit; | |
76 | ||
77 | trans = btrfs_start_transaction(root, 1); | |
78 | BUG_ON(!trans); | |
79 | ||
80 | ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root, | |
81 | 0, &objectid); | |
82 | if (ret) | |
83 | goto fail; | |
84 | ||
85 | leaf = btrfs_alloc_free_block(trans, root, root->leafsize, | |
86 | 0, objectid, NULL, 0, 0, 0); | |
87 | if (IS_ERR(leaf)) { | |
88 | ret = PTR_ERR(leaf); | |
89 | goto fail; | |
90 | } | |
91 | ||
92 | memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header)); | |
93 | btrfs_set_header_bytenr(leaf, leaf->start); | |
94 | btrfs_set_header_generation(leaf, trans->transid); | |
95 | btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV); | |
96 | btrfs_set_header_owner(leaf, objectid); | |
97 | ||
98 | write_extent_buffer(leaf, root->fs_info->fsid, | |
99 | (unsigned long)btrfs_header_fsid(leaf), | |
100 | BTRFS_FSID_SIZE); | |
101 | write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, | |
102 | (unsigned long)btrfs_header_chunk_tree_uuid(leaf), | |
103 | BTRFS_UUID_SIZE); | |
104 | btrfs_mark_buffer_dirty(leaf); | |
105 | ||
106 | inode_item = &root_item.inode; | |
107 | memset(inode_item, 0, sizeof(*inode_item)); | |
108 | inode_item->generation = cpu_to_le64(1); | |
109 | inode_item->size = cpu_to_le64(3); | |
110 | inode_item->nlink = cpu_to_le32(1); | |
111 | inode_item->nbytes = cpu_to_le64(root->leafsize); | |
112 | inode_item->mode = cpu_to_le32(S_IFDIR | 0755); | |
113 | ||
114 | btrfs_set_root_bytenr(&root_item, leaf->start); | |
115 | btrfs_set_root_generation(&root_item, trans->transid); | |
116 | btrfs_set_root_level(&root_item, 0); | |
117 | btrfs_set_root_refs(&root_item, 1); | |
118 | btrfs_set_root_used(&root_item, 0); | |
119 | btrfs_set_root_last_snapshot(&root_item, 0); | |
120 | ||
121 | memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress)); | |
122 | root_item.drop_level = 0; | |
123 | ||
124 | btrfs_tree_unlock(leaf); | |
125 | free_extent_buffer(leaf); | |
126 | leaf = NULL; | |
127 | ||
128 | btrfs_set_root_dirid(&root_item, new_dirid); | |
129 | ||
130 | key.objectid = objectid; | |
131 | key.offset = 0; | |
132 | btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); | |
133 | ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key, | |
134 | &root_item); | |
135 | if (ret) | |
136 | goto fail; | |
137 | ||
138 | /* | |
139 | * insert the directory item | |
140 | */ | |
141 | key.offset = (u64)-1; | |
142 | dir = dentry->d_parent->d_inode; | |
143 | ret = btrfs_set_inode_index(dir, &index); | |
144 | BUG_ON(ret); | |
145 | ||
146 | ret = btrfs_insert_dir_item(trans, root, | |
147 | name, namelen, dir->i_ino, &key, | |
148 | BTRFS_FT_DIR, index); | |
149 | if (ret) | |
150 | goto fail; | |
151 | ||
152 | btrfs_i_size_write(dir, dir->i_size + namelen * 2); | |
153 | ret = btrfs_update_inode(trans, root, dir); | |
154 | BUG_ON(ret); | |
155 | ||
156 | /* add the backref first */ | |
157 | ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, | |
158 | objectid, BTRFS_ROOT_BACKREF_KEY, | |
159 | root->root_key.objectid, | |
160 | dir->i_ino, index, name, namelen); | |
161 | ||
162 | BUG_ON(ret); | |
163 | ||
164 | /* now add the forward ref */ | |
165 | ret = btrfs_add_root_ref(trans, root->fs_info->tree_root, | |
166 | root->root_key.objectid, BTRFS_ROOT_REF_KEY, | |
167 | objectid, | |
168 | dir->i_ino, index, name, namelen); | |
169 | ||
170 | BUG_ON(ret); | |
171 | ||
172 | ret = btrfs_commit_transaction(trans, root); | |
173 | if (ret) | |
174 | goto fail_commit; | |
175 | ||
176 | new_root = btrfs_read_fs_root_no_name(root->fs_info, &key); | |
177 | BUG_ON(!new_root); | |
178 | ||
179 | trans = btrfs_start_transaction(new_root, 1); | |
180 | BUG_ON(!trans); | |
181 | ||
182 | ret = btrfs_create_subvol_root(trans, new_root, dentry, new_dirid, | |
183 | BTRFS_I(dir)->block_group); | |
184 | if (ret) | |
185 | goto fail; | |
186 | ||
187 | fail: | |
188 | nr = trans->blocks_used; | |
189 | err = btrfs_commit_transaction(trans, new_root); | |
190 | if (err && !ret) | |
191 | ret = err; | |
192 | fail_commit: | |
193 | btrfs_btree_balance_dirty(root, nr); | |
194 | return ret; | |
195 | } | |
196 | ||
197 | static int create_snapshot(struct btrfs_root *root, struct dentry *dentry, | |
198 | char *name, int namelen) | |
199 | { | |
200 | struct btrfs_pending_snapshot *pending_snapshot; | |
201 | struct btrfs_trans_handle *trans; | |
202 | int ret = 0; | |
203 | int err; | |
204 | unsigned long nr = 0; | |
205 | ||
206 | if (!root->ref_cows) | |
207 | return -EINVAL; | |
208 | ||
209 | ret = btrfs_check_metadata_free_space(root); | |
210 | if (ret) | |
211 | goto fail_unlock; | |
212 | ||
213 | pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS); | |
214 | if (!pending_snapshot) { | |
215 | ret = -ENOMEM; | |
216 | goto fail_unlock; | |
217 | } | |
218 | pending_snapshot->name = kmalloc(namelen + 1, GFP_NOFS); | |
219 | if (!pending_snapshot->name) { | |
220 | ret = -ENOMEM; | |
221 | kfree(pending_snapshot); | |
222 | goto fail_unlock; | |
223 | } | |
224 | memcpy(pending_snapshot->name, name, namelen); | |
225 | pending_snapshot->name[namelen] = '\0'; | |
226 | pending_snapshot->dentry = dentry; | |
227 | trans = btrfs_start_transaction(root, 1); | |
228 | BUG_ON(!trans); | |
229 | pending_snapshot->root = root; | |
230 | list_add(&pending_snapshot->list, | |
231 | &trans->transaction->pending_snapshots); | |
232 | err = btrfs_commit_transaction(trans, root); | |
233 | ||
234 | fail_unlock: | |
235 | btrfs_btree_balance_dirty(root, nr); | |
236 | return ret; | |
237 | } | |
238 | ||
239 | /* copy of may_create in fs/namei.c() */ | |
240 | static inline int btrfs_may_create(struct inode *dir, struct dentry *child) | |
241 | { | |
242 | if (child->d_inode) | |
243 | return -EEXIST; | |
244 | if (IS_DEADDIR(dir)) | |
245 | return -ENOENT; | |
246 | return inode_permission(dir, MAY_WRITE | MAY_EXEC); | |
247 | } | |
248 | ||
249 | /* | |
250 | * Create a new subvolume below @parent. This is largely modeled after | |
251 | * sys_mkdirat and vfs_mkdir, but we only do a single component lookup | |
252 | * inside this filesystem so it's quite a bit simpler. | |
253 | */ | |
254 | static noinline int btrfs_mksubvol(struct path *parent, char *name, | |
255 | int mode, int namelen, | |
256 | struct btrfs_root *snap_src) | |
257 | { | |
258 | struct dentry *dentry; | |
259 | int error; | |
260 | ||
261 | mutex_lock_nested(&parent->dentry->d_inode->i_mutex, I_MUTEX_PARENT); | |
262 | ||
263 | dentry = lookup_one_len(name, parent->dentry, namelen); | |
264 | error = PTR_ERR(dentry); | |
265 | if (IS_ERR(dentry)) | |
266 | goto out_unlock; | |
267 | ||
268 | error = -EEXIST; | |
269 | if (dentry->d_inode) | |
270 | goto out_dput; | |
271 | ||
272 | if (!IS_POSIXACL(parent->dentry->d_inode)) | |
273 | mode &= ~current_umask(); | |
274 | ||
275 | error = mnt_want_write(parent->mnt); | |
276 | if (error) | |
277 | goto out_dput; | |
278 | ||
279 | error = btrfs_may_create(parent->dentry->d_inode, dentry); | |
280 | if (error) | |
281 | goto out_drop_write; | |
282 | ||
283 | /* | |
284 | * Actually perform the low-level subvolume creation after all | |
285 | * this VFS fuzz. | |
286 | * | |
287 | * Eventually we want to pass in an inode under which we create this | |
288 | * subvolume, but for now all are under the filesystem root. | |
289 | * | |
290 | * Also we should pass on the mode eventually to allow creating new | |
291 | * subvolume with specific mode bits. | |
292 | */ | |
293 | if (snap_src) { | |
294 | struct dentry *dir = dentry->d_parent; | |
295 | struct dentry *test = dir->d_parent; | |
296 | struct btrfs_path *path = btrfs_alloc_path(); | |
297 | int ret; | |
298 | u64 test_oid; | |
299 | u64 parent_oid = BTRFS_I(dir->d_inode)->root->root_key.objectid; | |
300 | ||
301 | test_oid = snap_src->root_key.objectid; | |
302 | ||
303 | ret = btrfs_find_root_ref(snap_src->fs_info->tree_root, | |
304 | path, parent_oid, test_oid); | |
305 | if (ret == 0) | |
306 | goto create; | |
307 | btrfs_release_path(snap_src->fs_info->tree_root, path); | |
308 | ||
309 | /* we need to make sure we aren't creating a directory loop | |
310 | * by taking a snapshot of something that has our current | |
311 | * subvol in its directory tree. So, this loops through | |
312 | * the dentries and checks the forward refs for each subvolume | |
313 | * to see if is references the subvolume where we are | |
314 | * placing this new snapshot. | |
315 | */ | |
316 | while (1) { | |
317 | if (!test || | |
318 | dir == snap_src->fs_info->sb->s_root || | |
319 | test == snap_src->fs_info->sb->s_root || | |
320 | test->d_inode->i_sb != snap_src->fs_info->sb) { | |
321 | break; | |
322 | } | |
323 | if (S_ISLNK(test->d_inode->i_mode)) { | |
324 | printk(KERN_INFO "Btrfs symlink in snapshot " | |
325 | "path, failed\n"); | |
326 | error = -EMLINK; | |
327 | btrfs_free_path(path); | |
328 | goto out_drop_write; | |
329 | } | |
330 | test_oid = | |
331 | BTRFS_I(test->d_inode)->root->root_key.objectid; | |
332 | ret = btrfs_find_root_ref(snap_src->fs_info->tree_root, | |
333 | path, test_oid, parent_oid); | |
334 | if (ret == 0) { | |
335 | printk(KERN_INFO "Btrfs snapshot creation " | |
336 | "failed, looping\n"); | |
337 | error = -EMLINK; | |
338 | btrfs_free_path(path); | |
339 | goto out_drop_write; | |
340 | } | |
341 | btrfs_release_path(snap_src->fs_info->tree_root, path); | |
342 | test = test->d_parent; | |
343 | } | |
344 | create: | |
345 | btrfs_free_path(path); | |
346 | error = create_snapshot(snap_src, dentry, name, namelen); | |
347 | } else { | |
348 | error = create_subvol(BTRFS_I(parent->dentry->d_inode)->root, | |
349 | dentry, name, namelen); | |
350 | } | |
351 | if (error) | |
352 | goto out_drop_write; | |
353 | ||
354 | fsnotify_mkdir(parent->dentry->d_inode, dentry); | |
355 | out_drop_write: | |
356 | mnt_drop_write(parent->mnt); | |
357 | out_dput: | |
358 | dput(dentry); | |
359 | out_unlock: | |
360 | mutex_unlock(&parent->dentry->d_inode->i_mutex); | |
361 | return error; | |
362 | } | |
363 | ||
364 | ||
365 | static int btrfs_defrag_file(struct file *file) | |
366 | { | |
367 | struct inode *inode = fdentry(file)->d_inode; | |
368 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
369 | struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; | |
370 | struct btrfs_ordered_extent *ordered; | |
371 | struct page *page; | |
372 | unsigned long last_index; | |
373 | unsigned long ra_pages = root->fs_info->bdi.ra_pages; | |
374 | unsigned long total_read = 0; | |
375 | u64 page_start; | |
376 | u64 page_end; | |
377 | unsigned long i; | |
378 | int ret; | |
379 | ||
380 | ret = btrfs_check_data_free_space(root, inode, inode->i_size); | |
381 | if (ret) | |
382 | return -ENOSPC; | |
383 | ||
384 | mutex_lock(&inode->i_mutex); | |
385 | last_index = inode->i_size >> PAGE_CACHE_SHIFT; | |
386 | for (i = 0; i <= last_index; i++) { | |
387 | if (total_read % ra_pages == 0) { | |
388 | btrfs_force_ra(inode->i_mapping, &file->f_ra, file, i, | |
389 | min(last_index, i + ra_pages - 1)); | |
390 | } | |
391 | total_read++; | |
392 | again: | |
393 | page = grab_cache_page(inode->i_mapping, i); | |
394 | if (!page) | |
395 | goto out_unlock; | |
396 | if (!PageUptodate(page)) { | |
397 | btrfs_readpage(NULL, page); | |
398 | lock_page(page); | |
399 | if (!PageUptodate(page)) { | |
400 | unlock_page(page); | |
401 | page_cache_release(page); | |
402 | goto out_unlock; | |
403 | } | |
404 | } | |
405 | ||
406 | wait_on_page_writeback(page); | |
407 | ||
408 | page_start = (u64)page->index << PAGE_CACHE_SHIFT; | |
409 | page_end = page_start + PAGE_CACHE_SIZE - 1; | |
410 | lock_extent(io_tree, page_start, page_end, GFP_NOFS); | |
411 | ||
412 | ordered = btrfs_lookup_ordered_extent(inode, page_start); | |
413 | if (ordered) { | |
414 | unlock_extent(io_tree, page_start, page_end, GFP_NOFS); | |
415 | unlock_page(page); | |
416 | page_cache_release(page); | |
417 | btrfs_start_ordered_extent(inode, ordered, 1); | |
418 | btrfs_put_ordered_extent(ordered); | |
419 | goto again; | |
420 | } | |
421 | set_page_extent_mapped(page); | |
422 | ||
423 | /* | |
424 | * this makes sure page_mkwrite is called on the | |
425 | * page if it is dirtied again later | |
426 | */ | |
427 | clear_page_dirty_for_io(page); | |
428 | ||
429 | btrfs_set_extent_delalloc(inode, page_start, page_end); | |
430 | ||
431 | unlock_extent(io_tree, page_start, page_end, GFP_NOFS); | |
432 | set_page_dirty(page); | |
433 | unlock_page(page); | |
434 | page_cache_release(page); | |
435 | balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1); | |
436 | } | |
437 | ||
438 | out_unlock: | |
439 | mutex_unlock(&inode->i_mutex); | |
440 | return 0; | |
441 | } | |
442 | ||
443 | static int btrfs_ioctl_resize(struct btrfs_root *root, void __user *arg) | |
444 | { | |
445 | u64 new_size; | |
446 | u64 old_size; | |
447 | u64 devid = 1; | |
448 | struct btrfs_ioctl_vol_args *vol_args; | |
449 | struct btrfs_trans_handle *trans; | |
450 | struct btrfs_device *device = NULL; | |
451 | char *sizestr; | |
452 | char *devstr = NULL; | |
453 | int ret = 0; | |
454 | int namelen; | |
455 | int mod = 0; | |
456 | ||
457 | if (root->fs_info->sb->s_flags & MS_RDONLY) | |
458 | return -EROFS; | |
459 | ||
460 | if (!capable(CAP_SYS_ADMIN)) | |
461 | return -EPERM; | |
462 | ||
463 | vol_args = memdup_user(arg, sizeof(*vol_args)); | |
464 | if (IS_ERR(vol_args)) | |
465 | return PTR_ERR(vol_args); | |
466 | ||
467 | vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; | |
468 | namelen = strlen(vol_args->name); | |
469 | ||
470 | mutex_lock(&root->fs_info->volume_mutex); | |
471 | sizestr = vol_args->name; | |
472 | devstr = strchr(sizestr, ':'); | |
473 | if (devstr) { | |
474 | char *end; | |
475 | sizestr = devstr + 1; | |
476 | *devstr = '\0'; | |
477 | devstr = vol_args->name; | |
478 | devid = simple_strtoull(devstr, &end, 10); | |
479 | printk(KERN_INFO "resizing devid %llu\n", | |
480 | (unsigned long long)devid); | |
481 | } | |
482 | device = btrfs_find_device(root, devid, NULL, NULL); | |
483 | if (!device) { | |
484 | printk(KERN_INFO "resizer unable to find device %llu\n", | |
485 | (unsigned long long)devid); | |
486 | ret = -EINVAL; | |
487 | goto out_unlock; | |
488 | } | |
489 | if (!strcmp(sizestr, "max")) | |
490 | new_size = device->bdev->bd_inode->i_size; | |
491 | else { | |
492 | if (sizestr[0] == '-') { | |
493 | mod = -1; | |
494 | sizestr++; | |
495 | } else if (sizestr[0] == '+') { | |
496 | mod = 1; | |
497 | sizestr++; | |
498 | } | |
499 | new_size = btrfs_parse_size(sizestr); | |
500 | if (new_size == 0) { | |
501 | ret = -EINVAL; | |
502 | goto out_unlock; | |
503 | } | |
504 | } | |
505 | ||
506 | old_size = device->total_bytes; | |
507 | ||
508 | if (mod < 0) { | |
509 | if (new_size > old_size) { | |
510 | ret = -EINVAL; | |
511 | goto out_unlock; | |
512 | } | |
513 | new_size = old_size - new_size; | |
514 | } else if (mod > 0) { | |
515 | new_size = old_size + new_size; | |
516 | } | |
517 | ||
518 | if (new_size < 256 * 1024 * 1024) { | |
519 | ret = -EINVAL; | |
520 | goto out_unlock; | |
521 | } | |
522 | if (new_size > device->bdev->bd_inode->i_size) { | |
523 | ret = -EFBIG; | |
524 | goto out_unlock; | |
525 | } | |
526 | ||
527 | do_div(new_size, root->sectorsize); | |
528 | new_size *= root->sectorsize; | |
529 | ||
530 | printk(KERN_INFO "new size for %s is %llu\n", | |
531 | device->name, (unsigned long long)new_size); | |
532 | ||
533 | if (new_size > old_size) { | |
534 | trans = btrfs_start_transaction(root, 1); | |
535 | ret = btrfs_grow_device(trans, device, new_size); | |
536 | btrfs_commit_transaction(trans, root); | |
537 | } else { | |
538 | ret = btrfs_shrink_device(device, new_size); | |
539 | } | |
540 | ||
541 | out_unlock: | |
542 | mutex_unlock(&root->fs_info->volume_mutex); | |
543 | kfree(vol_args); | |
544 | return ret; | |
545 | } | |
546 | ||
547 | static noinline int btrfs_ioctl_snap_create(struct file *file, | |
548 | void __user *arg, int subvol) | |
549 | { | |
550 | struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; | |
551 | struct btrfs_ioctl_vol_args *vol_args; | |
552 | struct btrfs_dir_item *di; | |
553 | struct btrfs_path *path; | |
554 | struct file *src_file; | |
555 | u64 root_dirid; | |
556 | int namelen; | |
557 | int ret = 0; | |
558 | ||
559 | if (root->fs_info->sb->s_flags & MS_RDONLY) | |
560 | return -EROFS; | |
561 | ||
562 | vol_args = memdup_user(arg, sizeof(*vol_args)); | |
563 | if (IS_ERR(vol_args)) | |
564 | return PTR_ERR(vol_args); | |
565 | ||
566 | vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; | |
567 | namelen = strlen(vol_args->name); | |
568 | if (strchr(vol_args->name, '/')) { | |
569 | ret = -EINVAL; | |
570 | goto out; | |
571 | } | |
572 | ||
573 | path = btrfs_alloc_path(); | |
574 | if (!path) { | |
575 | ret = -ENOMEM; | |
576 | goto out; | |
577 | } | |
578 | ||
579 | root_dirid = root->fs_info->sb->s_root->d_inode->i_ino, | |
580 | di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, | |
581 | path, root_dirid, | |
582 | vol_args->name, namelen, 0); | |
583 | btrfs_free_path(path); | |
584 | ||
585 | if (di && !IS_ERR(di)) { | |
586 | ret = -EEXIST; | |
587 | goto out; | |
588 | } | |
589 | ||
590 | if (IS_ERR(di)) { | |
591 | ret = PTR_ERR(di); | |
592 | goto out; | |
593 | } | |
594 | ||
595 | if (subvol) { | |
596 | ret = btrfs_mksubvol(&file->f_path, vol_args->name, | |
597 | file->f_path.dentry->d_inode->i_mode, | |
598 | namelen, NULL); | |
599 | } else { | |
600 | struct inode *src_inode; | |
601 | src_file = fget(vol_args->fd); | |
602 | if (!src_file) { | |
603 | ret = -EINVAL; | |
604 | goto out; | |
605 | } | |
606 | ||
607 | src_inode = src_file->f_path.dentry->d_inode; | |
608 | if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) { | |
609 | printk(KERN_INFO "btrfs: Snapshot src from " | |
610 | "another FS\n"); | |
611 | ret = -EINVAL; | |
612 | fput(src_file); | |
613 | goto out; | |
614 | } | |
615 | ret = btrfs_mksubvol(&file->f_path, vol_args->name, | |
616 | file->f_path.dentry->d_inode->i_mode, | |
617 | namelen, BTRFS_I(src_inode)->root); | |
618 | fput(src_file); | |
619 | } | |
620 | ||
621 | out: | |
622 | kfree(vol_args); | |
623 | return ret; | |
624 | } | |
625 | ||
626 | static int btrfs_ioctl_defrag(struct file *file) | |
627 | { | |
628 | struct inode *inode = fdentry(file)->d_inode; | |
629 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
630 | int ret; | |
631 | ||
632 | ret = mnt_want_write(file->f_path.mnt); | |
633 | if (ret) | |
634 | return ret; | |
635 | ||
636 | switch (inode->i_mode & S_IFMT) { | |
637 | case S_IFDIR: | |
638 | if (!capable(CAP_SYS_ADMIN)) { | |
639 | ret = -EPERM; | |
640 | goto out; | |
641 | } | |
642 | btrfs_defrag_root(root, 0); | |
643 | btrfs_defrag_root(root->fs_info->extent_root, 0); | |
644 | break; | |
645 | case S_IFREG: | |
646 | if (!(file->f_mode & FMODE_WRITE)) { | |
647 | ret = -EINVAL; | |
648 | goto out; | |
649 | } | |
650 | btrfs_defrag_file(file); | |
651 | break; | |
652 | } | |
653 | out: | |
654 | mnt_drop_write(file->f_path.mnt); | |
655 | return ret; | |
656 | } | |
657 | ||
658 | static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg) | |
659 | { | |
660 | struct btrfs_ioctl_vol_args *vol_args; | |
661 | int ret; | |
662 | ||
663 | if (!capable(CAP_SYS_ADMIN)) | |
664 | return -EPERM; | |
665 | ||
666 | vol_args = memdup_user(arg, sizeof(*vol_args)); | |
667 | if (IS_ERR(vol_args)) | |
668 | return PTR_ERR(vol_args); | |
669 | ||
670 | vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; | |
671 | ret = btrfs_init_new_device(root, vol_args->name); | |
672 | ||
673 | kfree(vol_args); | |
674 | return ret; | |
675 | } | |
676 | ||
677 | static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg) | |
678 | { | |
679 | struct btrfs_ioctl_vol_args *vol_args; | |
680 | int ret; | |
681 | ||
682 | if (!capable(CAP_SYS_ADMIN)) | |
683 | return -EPERM; | |
684 | ||
685 | if (root->fs_info->sb->s_flags & MS_RDONLY) | |
686 | return -EROFS; | |
687 | ||
688 | vol_args = memdup_user(arg, sizeof(*vol_args)); | |
689 | if (IS_ERR(vol_args)) | |
690 | return PTR_ERR(vol_args); | |
691 | ||
692 | vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; | |
693 | ret = btrfs_rm_device(root, vol_args->name); | |
694 | ||
695 | kfree(vol_args); | |
696 | return ret; | |
697 | } | |
698 | ||
699 | static long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, | |
700 | u64 off, u64 olen, u64 destoff) | |
701 | { | |
702 | struct inode *inode = fdentry(file)->d_inode; | |
703 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
704 | struct file *src_file; | |
705 | struct inode *src; | |
706 | struct btrfs_trans_handle *trans; | |
707 | struct btrfs_path *path; | |
708 | struct extent_buffer *leaf; | |
709 | char *buf; | |
710 | struct btrfs_key key; | |
711 | u32 nritems; | |
712 | int slot; | |
713 | int ret; | |
714 | u64 len = olen; | |
715 | u64 bs = root->fs_info->sb->s_blocksize; | |
716 | u64 hint_byte; | |
717 | ||
718 | /* | |
719 | * TODO: | |
720 | * - split compressed inline extents. annoying: we need to | |
721 | * decompress into destination's address_space (the file offset | |
722 | * may change, so source mapping won't do), then recompress (or | |
723 | * otherwise reinsert) a subrange. | |
724 | * - allow ranges within the same file to be cloned (provided | |
725 | * they don't overlap)? | |
726 | */ | |
727 | ||
728 | /* the destination must be opened for writing */ | |
729 | if (!(file->f_mode & FMODE_WRITE)) | |
730 | return -EINVAL; | |
731 | ||
732 | ret = mnt_want_write(file->f_path.mnt); | |
733 | if (ret) | |
734 | return ret; | |
735 | ||
736 | src_file = fget(srcfd); | |
737 | if (!src_file) { | |
738 | ret = -EBADF; | |
739 | goto out_drop_write; | |
740 | } | |
741 | src = src_file->f_dentry->d_inode; | |
742 | ||
743 | ret = -EINVAL; | |
744 | if (src == inode) | |
745 | goto out_fput; | |
746 | ||
747 | ret = -EISDIR; | |
748 | if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) | |
749 | goto out_fput; | |
750 | ||
751 | ret = -EXDEV; | |
752 | if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root) | |
753 | goto out_fput; | |
754 | ||
755 | ret = -ENOMEM; | |
756 | buf = vmalloc(btrfs_level_size(root, 0)); | |
757 | if (!buf) | |
758 | goto out_fput; | |
759 | ||
760 | path = btrfs_alloc_path(); | |
761 | if (!path) { | |
762 | vfree(buf); | |
763 | goto out_fput; | |
764 | } | |
765 | path->reada = 2; | |
766 | ||
767 | if (inode < src) { | |
768 | mutex_lock(&inode->i_mutex); | |
769 | mutex_lock(&src->i_mutex); | |
770 | } else { | |
771 | mutex_lock(&src->i_mutex); | |
772 | mutex_lock(&inode->i_mutex); | |
773 | } | |
774 | ||
775 | /* determine range to clone */ | |
776 | ret = -EINVAL; | |
777 | if (off >= src->i_size || off + len > src->i_size) | |
778 | goto out_unlock; | |
779 | if (len == 0) | |
780 | olen = len = src->i_size - off; | |
781 | /* if we extend to eof, continue to block boundary */ | |
782 | if (off + len == src->i_size) | |
783 | len = ((src->i_size + bs-1) & ~(bs-1)) | |
784 | - off; | |
785 | ||
786 | /* verify the end result is block aligned */ | |
787 | if ((off & (bs-1)) || | |
788 | ((off + len) & (bs-1))) | |
789 | goto out_unlock; | |
790 | ||
791 | /* do any pending delalloc/csum calc on src, one way or | |
792 | another, and lock file content */ | |
793 | while (1) { | |
794 | struct btrfs_ordered_extent *ordered; | |
795 | lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); | |
796 | ordered = btrfs_lookup_first_ordered_extent(inode, off+len); | |
797 | if (BTRFS_I(src)->delalloc_bytes == 0 && !ordered) | |
798 | break; | |
799 | unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); | |
800 | if (ordered) | |
801 | btrfs_put_ordered_extent(ordered); | |
802 | btrfs_wait_ordered_range(src, off, off+len); | |
803 | } | |
804 | ||
805 | trans = btrfs_start_transaction(root, 1); | |
806 | BUG_ON(!trans); | |
807 | ||
808 | /* punch hole in destination first */ | |
809 | btrfs_drop_extents(trans, root, inode, off, off + len, | |
810 | off + len, 0, &hint_byte); | |
811 | ||
812 | /* clone data */ | |
813 | key.objectid = src->i_ino; | |
814 | key.type = BTRFS_EXTENT_DATA_KEY; | |
815 | key.offset = 0; | |
816 | ||
817 | while (1) { | |
818 | /* | |
819 | * note the key will change type as we walk through the | |
820 | * tree. | |
821 | */ | |
822 | ret = btrfs_search_slot(trans, root, &key, path, 0, 0); | |
823 | if (ret < 0) | |
824 | goto out; | |
825 | ||
826 | nritems = btrfs_header_nritems(path->nodes[0]); | |
827 | if (path->slots[0] >= nritems) { | |
828 | ret = btrfs_next_leaf(root, path); | |
829 | if (ret < 0) | |
830 | goto out; | |
831 | if (ret > 0) | |
832 | break; | |
833 | nritems = btrfs_header_nritems(path->nodes[0]); | |
834 | } | |
835 | leaf = path->nodes[0]; | |
836 | slot = path->slots[0]; | |
837 | ||
838 | btrfs_item_key_to_cpu(leaf, &key, slot); | |
839 | if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY || | |
840 | key.objectid != src->i_ino) | |
841 | break; | |
842 | ||
843 | if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) { | |
844 | struct btrfs_file_extent_item *extent; | |
845 | int type; | |
846 | u32 size; | |
847 | struct btrfs_key new_key; | |
848 | u64 disko = 0, diskl = 0; | |
849 | u64 datao = 0, datal = 0; | |
850 | u8 comp; | |
851 | ||
852 | size = btrfs_item_size_nr(leaf, slot); | |
853 | read_extent_buffer(leaf, buf, | |
854 | btrfs_item_ptr_offset(leaf, slot), | |
855 | size); | |
856 | ||
857 | extent = btrfs_item_ptr(leaf, slot, | |
858 | struct btrfs_file_extent_item); | |
859 | comp = btrfs_file_extent_compression(leaf, extent); | |
860 | type = btrfs_file_extent_type(leaf, extent); | |
861 | if (type == BTRFS_FILE_EXTENT_REG) { | |
862 | disko = btrfs_file_extent_disk_bytenr(leaf, | |
863 | extent); | |
864 | diskl = btrfs_file_extent_disk_num_bytes(leaf, | |
865 | extent); | |
866 | datao = btrfs_file_extent_offset(leaf, extent); | |
867 | datal = btrfs_file_extent_num_bytes(leaf, | |
868 | extent); | |
869 | } else if (type == BTRFS_FILE_EXTENT_INLINE) { | |
870 | /* take upper bound, may be compressed */ | |
871 | datal = btrfs_file_extent_ram_bytes(leaf, | |
872 | extent); | |
873 | } | |
874 | btrfs_release_path(root, path); | |
875 | ||
876 | if (key.offset + datal < off || | |
877 | key.offset >= off+len) | |
878 | goto next; | |
879 | ||
880 | memcpy(&new_key, &key, sizeof(new_key)); | |
881 | new_key.objectid = inode->i_ino; | |
882 | new_key.offset = key.offset + destoff - off; | |
883 | ||
884 | if (type == BTRFS_FILE_EXTENT_REG) { | |
885 | ret = btrfs_insert_empty_item(trans, root, path, | |
886 | &new_key, size); | |
887 | if (ret) | |
888 | goto out; | |
889 | ||
890 | leaf = path->nodes[0]; | |
891 | slot = path->slots[0]; | |
892 | write_extent_buffer(leaf, buf, | |
893 | btrfs_item_ptr_offset(leaf, slot), | |
894 | size); | |
895 | ||
896 | extent = btrfs_item_ptr(leaf, slot, | |
897 | struct btrfs_file_extent_item); | |
898 | ||
899 | if (off > key.offset) { | |
900 | datao += off - key.offset; | |
901 | datal -= off - key.offset; | |
902 | } | |
903 | if (key.offset + datao + datal + key.offset > | |
904 | off + len) | |
905 | datal = off + len - key.offset - datao; | |
906 | /* disko == 0 means it's a hole */ | |
907 | if (!disko) | |
908 | datao = 0; | |
909 | ||
910 | btrfs_set_file_extent_offset(leaf, extent, | |
911 | datao); | |
912 | btrfs_set_file_extent_num_bytes(leaf, extent, | |
913 | datal); | |
914 | if (disko) { | |
915 | inode_add_bytes(inode, datal); | |
916 | ret = btrfs_inc_extent_ref(trans, root, | |
917 | disko, diskl, 0, | |
918 | root->root_key.objectid, | |
919 | inode->i_ino, | |
920 | new_key.offset - datao); | |
921 | BUG_ON(ret); | |
922 | } | |
923 | } else if (type == BTRFS_FILE_EXTENT_INLINE) { | |
924 | u64 skip = 0; | |
925 | u64 trim = 0; | |
926 | if (off > key.offset) { | |
927 | skip = off - key.offset; | |
928 | new_key.offset += skip; | |
929 | } | |
930 | ||
931 | if (key.offset + datal > off+len) | |
932 | trim = key.offset + datal - (off+len); | |
933 | ||
934 | if (comp && (skip || trim)) { | |
935 | ret = -EINVAL; | |
936 | goto out; | |
937 | } | |
938 | size -= skip + trim; | |
939 | datal -= skip + trim; | |
940 | ret = btrfs_insert_empty_item(trans, root, path, | |
941 | &new_key, size); | |
942 | if (ret) | |
943 | goto out; | |
944 | ||
945 | if (skip) { | |
946 | u32 start = | |
947 | btrfs_file_extent_calc_inline_size(0); | |
948 | memmove(buf+start, buf+start+skip, | |
949 | datal); | |
950 | } | |
951 | ||
952 | leaf = path->nodes[0]; | |
953 | slot = path->slots[0]; | |
954 | write_extent_buffer(leaf, buf, | |
955 | btrfs_item_ptr_offset(leaf, slot), | |
956 | size); | |
957 | inode_add_bytes(inode, datal); | |
958 | } | |
959 | ||
960 | btrfs_mark_buffer_dirty(leaf); | |
961 | } | |
962 | ||
963 | next: | |
964 | btrfs_release_path(root, path); | |
965 | key.offset++; | |
966 | } | |
967 | ret = 0; | |
968 | out: | |
969 | btrfs_release_path(root, path); | |
970 | if (ret == 0) { | |
971 | inode->i_mtime = inode->i_ctime = CURRENT_TIME; | |
972 | if (destoff + olen > inode->i_size) | |
973 | btrfs_i_size_write(inode, destoff + olen); | |
974 | BTRFS_I(inode)->flags = BTRFS_I(src)->flags; | |
975 | ret = btrfs_update_inode(trans, root, inode); | |
976 | } | |
977 | btrfs_end_transaction(trans, root); | |
978 | unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS); | |
979 | if (ret) | |
980 | vmtruncate(inode, 0); | |
981 | out_unlock: | |
982 | mutex_unlock(&src->i_mutex); | |
983 | mutex_unlock(&inode->i_mutex); | |
984 | vfree(buf); | |
985 | btrfs_free_path(path); | |
986 | out_fput: | |
987 | fput(src_file); | |
988 | out_drop_write: | |
989 | mnt_drop_write(file->f_path.mnt); | |
990 | return ret; | |
991 | } | |
992 | ||
993 | static long btrfs_ioctl_clone_range(struct file *file, void __user *argp) | |
994 | { | |
995 | struct btrfs_ioctl_clone_range_args args; | |
996 | ||
997 | if (copy_from_user(&args, argp, sizeof(args))) | |
998 | return -EFAULT; | |
999 | return btrfs_ioctl_clone(file, args.src_fd, args.src_offset, | |
1000 | args.src_length, args.dest_offset); | |
1001 | } | |
1002 | ||
1003 | /* | |
1004 | * there are many ways the trans_start and trans_end ioctls can lead | |
1005 | * to deadlocks. They should only be used by applications that | |
1006 | * basically own the machine, and have a very in depth understanding | |
1007 | * of all the possible deadlocks and enospc problems. | |
1008 | */ | |
1009 | static long btrfs_ioctl_trans_start(struct file *file) | |
1010 | { | |
1011 | struct inode *inode = fdentry(file)->d_inode; | |
1012 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
1013 | struct btrfs_trans_handle *trans; | |
1014 | int ret = 0; | |
1015 | ||
1016 | if (!capable(CAP_SYS_ADMIN)) | |
1017 | return -EPERM; | |
1018 | ||
1019 | if (file->private_data) { | |
1020 | ret = -EINPROGRESS; | |
1021 | goto out; | |
1022 | } | |
1023 | ||
1024 | ret = mnt_want_write(file->f_path.mnt); | |
1025 | if (ret) | |
1026 | goto out; | |
1027 | ||
1028 | mutex_lock(&root->fs_info->trans_mutex); | |
1029 | root->fs_info->open_ioctl_trans++; | |
1030 | mutex_unlock(&root->fs_info->trans_mutex); | |
1031 | ||
1032 | trans = btrfs_start_ioctl_transaction(root, 0); | |
1033 | if (trans) | |
1034 | file->private_data = trans; | |
1035 | else | |
1036 | ret = -ENOMEM; | |
1037 | /*printk(KERN_INFO "btrfs_ioctl_trans_start on %p\n", file);*/ | |
1038 | out: | |
1039 | return ret; | |
1040 | } | |
1041 | ||
1042 | /* | |
1043 | * there are many ways the trans_start and trans_end ioctls can lead | |
1044 | * to deadlocks. They should only be used by applications that | |
1045 | * basically own the machine, and have a very in depth understanding | |
1046 | * of all the possible deadlocks and enospc problems. | |
1047 | */ | |
1048 | long btrfs_ioctl_trans_end(struct file *file) | |
1049 | { | |
1050 | struct inode *inode = fdentry(file)->d_inode; | |
1051 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
1052 | struct btrfs_trans_handle *trans; | |
1053 | int ret = 0; | |
1054 | ||
1055 | trans = file->private_data; | |
1056 | if (!trans) { | |
1057 | ret = -EINVAL; | |
1058 | goto out; | |
1059 | } | |
1060 | btrfs_end_transaction(trans, root); | |
1061 | file->private_data = NULL; | |
1062 | ||
1063 | mutex_lock(&root->fs_info->trans_mutex); | |
1064 | root->fs_info->open_ioctl_trans--; | |
1065 | mutex_unlock(&root->fs_info->trans_mutex); | |
1066 | ||
1067 | mnt_drop_write(file->f_path.mnt); | |
1068 | ||
1069 | out: | |
1070 | return ret; | |
1071 | } | |
1072 | ||
1073 | long btrfs_ioctl(struct file *file, unsigned int | |
1074 | cmd, unsigned long arg) | |
1075 | { | |
1076 | struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; | |
1077 | void __user *argp = (void __user *)arg; | |
1078 | ||
1079 | switch (cmd) { | |
1080 | case BTRFS_IOC_SNAP_CREATE: | |
1081 | return btrfs_ioctl_snap_create(file, argp, 0); | |
1082 | case BTRFS_IOC_SUBVOL_CREATE: | |
1083 | return btrfs_ioctl_snap_create(file, argp, 1); | |
1084 | case BTRFS_IOC_DEFRAG: | |
1085 | return btrfs_ioctl_defrag(file); | |
1086 | case BTRFS_IOC_RESIZE: | |
1087 | return btrfs_ioctl_resize(root, argp); | |
1088 | case BTRFS_IOC_ADD_DEV: | |
1089 | return btrfs_ioctl_add_dev(root, argp); | |
1090 | case BTRFS_IOC_RM_DEV: | |
1091 | return btrfs_ioctl_rm_dev(root, argp); | |
1092 | case BTRFS_IOC_BALANCE: | |
1093 | return btrfs_balance(root->fs_info->dev_root); | |
1094 | case BTRFS_IOC_CLONE: | |
1095 | return btrfs_ioctl_clone(file, arg, 0, 0, 0); | |
1096 | case BTRFS_IOC_CLONE_RANGE: | |
1097 | return btrfs_ioctl_clone_range(file, argp); | |
1098 | case BTRFS_IOC_TRANS_START: | |
1099 | return btrfs_ioctl_trans_start(file); | |
1100 | case BTRFS_IOC_TRANS_END: | |
1101 | return btrfs_ioctl_trans_end(file); | |
1102 | case BTRFS_IOC_SYNC: | |
1103 | btrfs_sync_fs(file->f_dentry->d_sb, 1); | |
1104 | return 0; | |
1105 | } | |
1106 | ||
1107 | return -ENOTTY; | |
1108 | } |