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Btrfs: Delete any remaining extent_maps before freeing the inode
[deliverable/linux.git] / fs / btrfs / inode.c
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/buffer_head.h>
20 #include <linux/fs.h>
21 #include <linux/pagemap.h>
22 #include <linux/highmem.h>
23 #include <linux/time.h>
24 #include <linux/init.h>
25 #include <linux/string.h>
26 #include <linux/smp_lock.h>
27 #include <linux/backing-dev.h>
28 #include <linux/mpage.h>
29 #include <linux/swap.h>
30 #include <linux/writeback.h>
31 #include <linux/statfs.h>
32 #include <linux/compat.h>
33 #include <linux/bit_spinlock.h>
34 #include <linux/version.h>
35 #include <linux/xattr.h>
36 #include "ctree.h"
37 #include "disk-io.h"
38 #include "transaction.h"
39 #include "btrfs_inode.h"
40 #include "ioctl.h"
41 #include "print-tree.h"
42
43 struct btrfs_iget_args {
44 u64 ino;
45 struct btrfs_root *root;
46 };
47
48 static struct inode_operations btrfs_dir_inode_operations;
49 static struct inode_operations btrfs_symlink_inode_operations;
50 static struct inode_operations btrfs_dir_ro_inode_operations;
51 static struct inode_operations btrfs_special_inode_operations;
52 static struct inode_operations btrfs_file_inode_operations;
53 static struct address_space_operations btrfs_aops;
54 static struct address_space_operations btrfs_symlink_aops;
55 static struct file_operations btrfs_dir_file_operations;
56 static struct extent_map_ops btrfs_extent_map_ops;
57
58 static struct kmem_cache *btrfs_inode_cachep;
59 struct kmem_cache *btrfs_trans_handle_cachep;
60 struct kmem_cache *btrfs_transaction_cachep;
61 struct kmem_cache *btrfs_bit_radix_cachep;
62 struct kmem_cache *btrfs_path_cachep;
63
64 #define S_SHIFT 12
65 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
66 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
67 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
68 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
69 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
70 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
71 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
72 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
73 };
74
75 int btrfs_check_free_space(struct btrfs_root *root, u64 num_required,
76 int for_del)
77 {
78 u64 total = btrfs_super_total_bytes(&root->fs_info->super_copy);
79 u64 used = btrfs_super_bytes_used(&root->fs_info->super_copy);
80 u64 thresh;
81 int ret = 0;
82
83 if (for_del)
84 thresh = total * 90;
85 else
86 thresh = total * 85;
87
88 do_div(thresh, 100);
89
90 spin_lock(&root->fs_info->delalloc_lock);
91 if (used + root->fs_info->delalloc_bytes + num_required > thresh)
92 ret = -ENOSPC;
93 spin_unlock(&root->fs_info->delalloc_lock);
94 return ret;
95 }
96
97 static int cow_file_range(struct inode *inode, u64 start, u64 end)
98 {
99 struct btrfs_root *root = BTRFS_I(inode)->root;
100 struct btrfs_trans_handle *trans;
101 u64 alloc_hint = 0;
102 u64 num_bytes;
103 u64 cur_alloc_size;
104 u64 blocksize = root->sectorsize;
105 struct btrfs_key ins;
106 int ret;
107
108 trans = btrfs_start_transaction(root, 1);
109 BUG_ON(!trans);
110 btrfs_set_trans_block_group(trans, inode);
111
112 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
113 num_bytes = max(blocksize, num_bytes);
114 ret = btrfs_drop_extents(trans, root, inode,
115 start, start + num_bytes, start, &alloc_hint);
116
117 if (alloc_hint == EXTENT_MAP_INLINE)
118 goto out;
119
120 while(num_bytes > 0) {
121 cur_alloc_size = min(num_bytes, root->fs_info->max_extent);
122 ret = btrfs_alloc_extent(trans, root, cur_alloc_size,
123 root->root_key.objectid,
124 trans->transid,
125 inode->i_ino, start, 0,
126 alloc_hint, (u64)-1, &ins, 1);
127 if (ret) {
128 WARN_ON(1);
129 goto out;
130 }
131 ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
132 start, ins.objectid, ins.offset,
133 ins.offset);
134 num_bytes -= cur_alloc_size;
135 alloc_hint = ins.objectid + ins.offset;
136 start += cur_alloc_size;
137 }
138 btrfs_add_ordered_inode(inode);
139 out:
140 btrfs_end_transaction(trans, root);
141 return ret;
142 }
143
144 static int run_delalloc_nocow(struct inode *inode, u64 start, u64 end)
145 {
146 u64 extent_start;
147 u64 extent_end;
148 u64 bytenr;
149 u64 cow_end;
150 u64 loops = 0;
151 u64 total_fs_bytes;
152 struct btrfs_root *root = BTRFS_I(inode)->root;
153 struct extent_buffer *leaf;
154 int found_type;
155 struct btrfs_path *path;
156 struct btrfs_file_extent_item *item;
157 int ret;
158 int err;
159 struct btrfs_key found_key;
160
161 total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
162 path = btrfs_alloc_path();
163 BUG_ON(!path);
164 again:
165 ret = btrfs_lookup_file_extent(NULL, root, path,
166 inode->i_ino, start, 0);
167 if (ret < 0) {
168 btrfs_free_path(path);
169 return ret;
170 }
171
172 cow_end = end;
173 if (ret != 0) {
174 if (path->slots[0] == 0)
175 goto not_found;
176 path->slots[0]--;
177 }
178
179 leaf = path->nodes[0];
180 item = btrfs_item_ptr(leaf, path->slots[0],
181 struct btrfs_file_extent_item);
182
183 /* are we inside the extent that was found? */
184 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
185 found_type = btrfs_key_type(&found_key);
186 if (found_key.objectid != inode->i_ino ||
187 found_type != BTRFS_EXTENT_DATA_KEY) {
188 goto not_found;
189 }
190
191 found_type = btrfs_file_extent_type(leaf, item);
192 extent_start = found_key.offset;
193 if (found_type == BTRFS_FILE_EXTENT_REG) {
194 u64 extent_num_bytes;
195
196 extent_num_bytes = btrfs_file_extent_num_bytes(leaf, item);
197 extent_end = extent_start + extent_num_bytes;
198 err = 0;
199
200 if (loops && start != extent_start)
201 goto not_found;
202
203 if (start < extent_start || start >= extent_end)
204 goto not_found;
205
206 cow_end = min(end, extent_end - 1);
207 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
208 if (bytenr == 0)
209 goto not_found;
210
211 /*
212 * we may be called by the resizer, make sure we're inside
213 * the limits of the FS
214 */
215 if (bytenr + extent_num_bytes > total_fs_bytes)
216 goto not_found;
217
218 if (btrfs_count_snapshots_in_path(root, path, bytenr) != 1) {
219 goto not_found;
220 }
221
222 start = extent_end;
223 } else {
224 goto not_found;
225 }
226 loop:
227 if (start > end) {
228 btrfs_free_path(path);
229 return 0;
230 }
231 btrfs_release_path(root, path);
232 loops++;
233 goto again;
234
235 not_found:
236 cow_file_range(inode, start, cow_end);
237 start = cow_end + 1;
238 goto loop;
239 }
240
241 static int run_delalloc_range(struct inode *inode, u64 start, u64 end)
242 {
243 struct btrfs_root *root = BTRFS_I(inode)->root;
244 u64 num_bytes;
245 int ret;
246 mutex_lock(&root->fs_info->fs_mutex);
247 if (btrfs_test_opt(root, NODATACOW) ||
248 btrfs_test_flag(inode, NODATACOW))
249 ret = run_delalloc_nocow(inode, start, end);
250 else
251 ret = cow_file_range(inode, start, end);
252
253 spin_lock(&root->fs_info->delalloc_lock);
254 num_bytes = end + 1 - start;
255 if (root->fs_info->delalloc_bytes < num_bytes) {
256 printk("delalloc accounting error total %llu sub %llu\n",
257 root->fs_info->delalloc_bytes, num_bytes);
258 } else {
259 root->fs_info->delalloc_bytes -= num_bytes;
260 }
261 spin_unlock(&root->fs_info->delalloc_lock);
262
263 mutex_unlock(&root->fs_info->fs_mutex);
264 return ret;
265 }
266
267 int btrfs_writepage_io_hook(struct page *page, u64 start, u64 end)
268 {
269 struct inode *inode = page->mapping->host;
270 struct btrfs_root *root = BTRFS_I(inode)->root;
271 struct btrfs_trans_handle *trans;
272 char *kaddr;
273 int ret = 0;
274 u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
275 size_t offset = start - page_start;
276 if (btrfs_test_opt(root, NODATASUM) ||
277 btrfs_test_flag(inode, NODATASUM))
278 return 0;
279 mutex_lock(&root->fs_info->fs_mutex);
280 trans = btrfs_start_transaction(root, 1);
281 btrfs_set_trans_block_group(trans, inode);
282 kaddr = kmap(page);
283 btrfs_csum_file_block(trans, root, inode, inode->i_ino,
284 start, kaddr + offset, end - start + 1);
285 kunmap(page);
286 ret = btrfs_end_transaction(trans, root);
287 BUG_ON(ret);
288 mutex_unlock(&root->fs_info->fs_mutex);
289 return ret;
290 }
291
292 int btrfs_readpage_io_hook(struct page *page, u64 start, u64 end)
293 {
294 int ret = 0;
295 struct inode *inode = page->mapping->host;
296 struct btrfs_root *root = BTRFS_I(inode)->root;
297 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
298 struct btrfs_csum_item *item;
299 struct btrfs_path *path = NULL;
300 u32 csum;
301 if (btrfs_test_opt(root, NODATASUM) ||
302 btrfs_test_flag(inode, NODATASUM))
303 return 0;
304 mutex_lock(&root->fs_info->fs_mutex);
305 path = btrfs_alloc_path();
306 item = btrfs_lookup_csum(NULL, root, path, inode->i_ino, start, 0);
307 if (IS_ERR(item)) {
308 ret = PTR_ERR(item);
309 /* a csum that isn't present is a preallocated region. */
310 if (ret == -ENOENT || ret == -EFBIG)
311 ret = 0;
312 csum = 0;
313 goto out;
314 }
315 read_extent_buffer(path->nodes[0], &csum, (unsigned long)item,
316 BTRFS_CRC32_SIZE);
317 set_state_private(em_tree, start, csum);
318 out:
319 if (path)
320 btrfs_free_path(path);
321 mutex_unlock(&root->fs_info->fs_mutex);
322 return ret;
323 }
324
325 int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end)
326 {
327 size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
328 struct inode *inode = page->mapping->host;
329 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
330 char *kaddr;
331 u64 private;
332 int ret;
333 struct btrfs_root *root = BTRFS_I(inode)->root;
334 u32 csum = ~(u32)0;
335 unsigned long flags;
336 if (btrfs_test_opt(root, NODATASUM) ||
337 btrfs_test_flag(inode, NODATASUM))
338 return 0;
339 ret = get_state_private(em_tree, start, &private);
340 local_irq_save(flags);
341 kaddr = kmap_atomic(page, KM_IRQ0);
342 if (ret) {
343 goto zeroit;
344 }
345 csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1);
346 btrfs_csum_final(csum, (char *)&csum);
347 if (csum != private) {
348 goto zeroit;
349 }
350 kunmap_atomic(kaddr, KM_IRQ0);
351 local_irq_restore(flags);
352 return 0;
353
354 zeroit:
355 printk("btrfs csum failed ino %lu off %llu\n",
356 page->mapping->host->i_ino, (unsigned long long)start);
357 memset(kaddr + offset, 1, end - start + 1);
358 flush_dcache_page(page);
359 kunmap_atomic(kaddr, KM_IRQ0);
360 local_irq_restore(flags);
361 return 0;
362 }
363
364 void btrfs_read_locked_inode(struct inode *inode)
365 {
366 struct btrfs_path *path;
367 struct extent_buffer *leaf;
368 struct btrfs_inode_item *inode_item;
369 struct btrfs_inode_timespec *tspec;
370 struct btrfs_root *root = BTRFS_I(inode)->root;
371 struct btrfs_key location;
372 u64 alloc_group_block;
373 u32 rdev;
374 int ret;
375
376 path = btrfs_alloc_path();
377 BUG_ON(!path);
378 mutex_lock(&root->fs_info->fs_mutex);
379 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
380
381 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
382 if (ret)
383 goto make_bad;
384
385 leaf = path->nodes[0];
386 inode_item = btrfs_item_ptr(leaf, path->slots[0],
387 struct btrfs_inode_item);
388
389 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
390 inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
391 inode->i_uid = btrfs_inode_uid(leaf, inode_item);
392 inode->i_gid = btrfs_inode_gid(leaf, inode_item);
393 inode->i_size = btrfs_inode_size(leaf, inode_item);
394
395 tspec = btrfs_inode_atime(inode_item);
396 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
397 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
398
399 tspec = btrfs_inode_mtime(inode_item);
400 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
401 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
402
403 tspec = btrfs_inode_ctime(inode_item);
404 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
405 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
406
407 inode->i_blocks = btrfs_inode_nblocks(leaf, inode_item);
408 inode->i_generation = btrfs_inode_generation(leaf, inode_item);
409 inode->i_rdev = 0;
410 rdev = btrfs_inode_rdev(leaf, inode_item);
411
412 alloc_group_block = btrfs_inode_block_group(leaf, inode_item);
413 BTRFS_I(inode)->block_group = btrfs_lookup_block_group(root->fs_info,
414 alloc_group_block);
415 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
416 if (!BTRFS_I(inode)->block_group) {
417 BTRFS_I(inode)->block_group = btrfs_find_block_group(root,
418 NULL, 0, 0, 0);
419 }
420 btrfs_free_path(path);
421 inode_item = NULL;
422
423 mutex_unlock(&root->fs_info->fs_mutex);
424
425 switch (inode->i_mode & S_IFMT) {
426 case S_IFREG:
427 inode->i_mapping->a_ops = &btrfs_aops;
428 BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
429 inode->i_fop = &btrfs_file_operations;
430 inode->i_op = &btrfs_file_inode_operations;
431 break;
432 case S_IFDIR:
433 inode->i_fop = &btrfs_dir_file_operations;
434 if (root == root->fs_info->tree_root)
435 inode->i_op = &btrfs_dir_ro_inode_operations;
436 else
437 inode->i_op = &btrfs_dir_inode_operations;
438 break;
439 case S_IFLNK:
440 inode->i_op = &btrfs_symlink_inode_operations;
441 inode->i_mapping->a_ops = &btrfs_symlink_aops;
442 break;
443 default:
444 init_special_inode(inode, inode->i_mode, rdev);
445 break;
446 }
447 return;
448
449 make_bad:
450 btrfs_release_path(root, path);
451 btrfs_free_path(path);
452 mutex_unlock(&root->fs_info->fs_mutex);
453 make_bad_inode(inode);
454 }
455
456 static void fill_inode_item(struct extent_buffer *leaf,
457 struct btrfs_inode_item *item,
458 struct inode *inode)
459 {
460 btrfs_set_inode_uid(leaf, item, inode->i_uid);
461 btrfs_set_inode_gid(leaf, item, inode->i_gid);
462 btrfs_set_inode_size(leaf, item, inode->i_size);
463 btrfs_set_inode_mode(leaf, item, inode->i_mode);
464 btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
465
466 btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
467 inode->i_atime.tv_sec);
468 btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
469 inode->i_atime.tv_nsec);
470
471 btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
472 inode->i_mtime.tv_sec);
473 btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
474 inode->i_mtime.tv_nsec);
475
476 btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
477 inode->i_ctime.tv_sec);
478 btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
479 inode->i_ctime.tv_nsec);
480
481 btrfs_set_inode_nblocks(leaf, item, inode->i_blocks);
482 btrfs_set_inode_generation(leaf, item, inode->i_generation);
483 btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
484 btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
485 btrfs_set_inode_block_group(leaf, item,
486 BTRFS_I(inode)->block_group->key.objectid);
487 }
488
489 int btrfs_update_inode(struct btrfs_trans_handle *trans,
490 struct btrfs_root *root,
491 struct inode *inode)
492 {
493 struct btrfs_inode_item *inode_item;
494 struct btrfs_path *path;
495 struct extent_buffer *leaf;
496 int ret;
497
498 path = btrfs_alloc_path();
499 BUG_ON(!path);
500 ret = btrfs_lookup_inode(trans, root, path,
501 &BTRFS_I(inode)->location, 1);
502 if (ret) {
503 if (ret > 0)
504 ret = -ENOENT;
505 goto failed;
506 }
507
508 leaf = path->nodes[0];
509 inode_item = btrfs_item_ptr(leaf, path->slots[0],
510 struct btrfs_inode_item);
511
512 fill_inode_item(leaf, inode_item, inode);
513 btrfs_mark_buffer_dirty(leaf);
514 btrfs_set_inode_last_trans(trans, inode);
515 ret = 0;
516 failed:
517 btrfs_release_path(root, path);
518 btrfs_free_path(path);
519 return ret;
520 }
521
522
523 static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
524 struct btrfs_root *root,
525 struct inode *dir,
526 struct dentry *dentry)
527 {
528 struct btrfs_path *path;
529 const char *name = dentry->d_name.name;
530 int name_len = dentry->d_name.len;
531 int ret = 0;
532 struct extent_buffer *leaf;
533 struct btrfs_dir_item *di;
534 struct btrfs_key key;
535
536 path = btrfs_alloc_path();
537 if (!path) {
538 ret = -ENOMEM;
539 goto err;
540 }
541
542 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
543 name, name_len, -1);
544 if (IS_ERR(di)) {
545 ret = PTR_ERR(di);
546 goto err;
547 }
548 if (!di) {
549 ret = -ENOENT;
550 goto err;
551 }
552 leaf = path->nodes[0];
553 btrfs_dir_item_key_to_cpu(leaf, di, &key);
554 ret = btrfs_delete_one_dir_name(trans, root, path, di);
555 if (ret)
556 goto err;
557 btrfs_release_path(root, path);
558
559 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
560 key.objectid, name, name_len, -1);
561 if (IS_ERR(di)) {
562 ret = PTR_ERR(di);
563 goto err;
564 }
565 if (!di) {
566 ret = -ENOENT;
567 goto err;
568 }
569 ret = btrfs_delete_one_dir_name(trans, root, path, di);
570
571 dentry->d_inode->i_ctime = dir->i_ctime;
572 ret = btrfs_del_inode_ref(trans, root, name, name_len,
573 dentry->d_inode->i_ino,
574 dentry->d_parent->d_inode->i_ino);
575 if (ret) {
576 printk("failed to delete reference to %.*s, "
577 "inode %lu parent %lu\n", name_len, name,
578 dentry->d_inode->i_ino,
579 dentry->d_parent->d_inode->i_ino);
580 }
581 err:
582 btrfs_free_path(path);
583 if (!ret) {
584 dir->i_size -= name_len * 2;
585 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
586 btrfs_update_inode(trans, root, dir);
587 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
588 dentry->d_inode->i_nlink--;
589 #else
590 drop_nlink(dentry->d_inode);
591 #endif
592 ret = btrfs_update_inode(trans, root, dentry->d_inode);
593 dir->i_sb->s_dirt = 1;
594 }
595 return ret;
596 }
597
598 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
599 {
600 struct btrfs_root *root;
601 struct btrfs_trans_handle *trans;
602 int ret;
603 unsigned long nr = 0;
604
605 root = BTRFS_I(dir)->root;
606 mutex_lock(&root->fs_info->fs_mutex);
607
608 ret = btrfs_check_free_space(root, 1, 1);
609 if (ret)
610 goto fail;
611
612 trans = btrfs_start_transaction(root, 1);
613
614 btrfs_set_trans_block_group(trans, dir);
615 ret = btrfs_unlink_trans(trans, root, dir, dentry);
616 nr = trans->blocks_used;
617
618 btrfs_end_transaction(trans, root);
619 fail:
620 mutex_unlock(&root->fs_info->fs_mutex);
621 btrfs_btree_balance_dirty(root, nr);
622 btrfs_throttle(root);
623 return ret;
624 }
625
626 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
627 {
628 struct inode *inode = dentry->d_inode;
629 int err = 0;
630 int ret;
631 struct btrfs_root *root = BTRFS_I(dir)->root;
632 struct btrfs_trans_handle *trans;
633 unsigned long nr = 0;
634
635 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
636 return -ENOTEMPTY;
637
638 mutex_lock(&root->fs_info->fs_mutex);
639 ret = btrfs_check_free_space(root, 1, 1);
640 if (ret)
641 goto fail;
642
643 trans = btrfs_start_transaction(root, 1);
644 btrfs_set_trans_block_group(trans, dir);
645
646 /* now the directory is empty */
647 err = btrfs_unlink_trans(trans, root, dir, dentry);
648 if (!err) {
649 inode->i_size = 0;
650 }
651
652 nr = trans->blocks_used;
653 ret = btrfs_end_transaction(trans, root);
654 fail:
655 mutex_unlock(&root->fs_info->fs_mutex);
656 btrfs_btree_balance_dirty(root, nr);
657 btrfs_throttle(root);
658
659 if (ret && !err)
660 err = ret;
661 return err;
662 }
663
664 static int btrfs_free_inode(struct btrfs_trans_handle *trans,
665 struct btrfs_root *root,
666 struct inode *inode)
667 {
668 struct btrfs_path *path;
669 int ret;
670
671 clear_inode(inode);
672
673 path = btrfs_alloc_path();
674 BUG_ON(!path);
675 ret = btrfs_lookup_inode(trans, root, path,
676 &BTRFS_I(inode)->location, -1);
677 if (ret > 0)
678 ret = -ENOENT;
679 if (!ret)
680 ret = btrfs_del_item(trans, root, path);
681 btrfs_free_path(path);
682 return ret;
683 }
684
685 /*
686 * this can truncate away extent items, csum items and directory items.
687 * It starts at a high offset and removes keys until it can't find
688 * any higher than i_size.
689 *
690 * csum items that cross the new i_size are truncated to the new size
691 * as well.
692 */
693 static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
694 struct btrfs_root *root,
695 struct inode *inode)
696 {
697 int ret;
698 struct btrfs_path *path;
699 struct btrfs_key key;
700 struct btrfs_key found_key;
701 u32 found_type;
702 struct extent_buffer *leaf;
703 struct btrfs_file_extent_item *fi;
704 u64 extent_start = 0;
705 u64 extent_num_bytes = 0;
706 u64 item_end = 0;
707 u64 root_gen = 0;
708 u64 root_owner = 0;
709 int found_extent;
710 int del_item;
711 int extent_type = -1;
712
713 btrfs_drop_extent_cache(inode, inode->i_size, (u64)-1);
714 path = btrfs_alloc_path();
715 path->reada = -1;
716 BUG_ON(!path);
717
718 /* FIXME, add redo link to tree so we don't leak on crash */
719 key.objectid = inode->i_ino;
720 key.offset = (u64)-1;
721 key.type = (u8)-1;
722
723 while(1) {
724 btrfs_init_path(path);
725 fi = NULL;
726 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
727 if (ret < 0) {
728 goto error;
729 }
730 if (ret > 0) {
731 BUG_ON(path->slots[0] == 0);
732 path->slots[0]--;
733 }
734 leaf = path->nodes[0];
735 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
736 found_type = btrfs_key_type(&found_key);
737
738 if (found_key.objectid != inode->i_ino)
739 break;
740
741 if (found_type != BTRFS_CSUM_ITEM_KEY &&
742 found_type != BTRFS_DIR_ITEM_KEY &&
743 found_type != BTRFS_DIR_INDEX_KEY &&
744 found_type != BTRFS_EXTENT_DATA_KEY)
745 break;
746
747 item_end = found_key.offset;
748 if (found_type == BTRFS_EXTENT_DATA_KEY) {
749 fi = btrfs_item_ptr(leaf, path->slots[0],
750 struct btrfs_file_extent_item);
751 extent_type = btrfs_file_extent_type(leaf, fi);
752 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
753 item_end +=
754 btrfs_file_extent_num_bytes(leaf, fi);
755 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
756 struct btrfs_item *item = btrfs_item_nr(leaf,
757 path->slots[0]);
758 item_end += btrfs_file_extent_inline_len(leaf,
759 item);
760 }
761 item_end--;
762 }
763 if (found_type == BTRFS_CSUM_ITEM_KEY) {
764 ret = btrfs_csum_truncate(trans, root, path,
765 inode->i_size);
766 BUG_ON(ret);
767 }
768 if (item_end < inode->i_size) {
769 if (found_type == BTRFS_DIR_ITEM_KEY) {
770 found_type = BTRFS_INODE_ITEM_KEY;
771 } else if (found_type == BTRFS_EXTENT_ITEM_KEY) {
772 found_type = BTRFS_CSUM_ITEM_KEY;
773 } else if (found_type) {
774 found_type--;
775 } else {
776 break;
777 }
778 btrfs_set_key_type(&key, found_type);
779 btrfs_release_path(root, path);
780 continue;
781 }
782 if (found_key.offset >= inode->i_size)
783 del_item = 1;
784 else
785 del_item = 0;
786 found_extent = 0;
787
788 /* FIXME, shrink the extent if the ref count is only 1 */
789 if (found_type != BTRFS_EXTENT_DATA_KEY)
790 goto delete;
791
792 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
793 u64 num_dec;
794 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
795 if (!del_item) {
796 u64 orig_num_bytes =
797 btrfs_file_extent_num_bytes(leaf, fi);
798 extent_num_bytes = inode->i_size -
799 found_key.offset + root->sectorsize - 1;
800 btrfs_set_file_extent_num_bytes(leaf, fi,
801 extent_num_bytes);
802 num_dec = (orig_num_bytes -
803 extent_num_bytes) >> 9;
804 if (extent_start != 0) {
805 inode->i_blocks -= num_dec;
806 }
807 btrfs_mark_buffer_dirty(leaf);
808 } else {
809 extent_num_bytes =
810 btrfs_file_extent_disk_num_bytes(leaf,
811 fi);
812 /* FIXME blocksize != 4096 */
813 num_dec = btrfs_file_extent_num_bytes(leaf,
814 fi) >> 9;
815 if (extent_start != 0) {
816 found_extent = 1;
817 inode->i_blocks -= num_dec;
818 }
819 root_gen = btrfs_header_generation(leaf);
820 root_owner = btrfs_header_owner(leaf);
821 }
822 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE &&
823 !del_item) {
824 u32 newsize = inode->i_size - found_key.offset;
825 newsize = btrfs_file_extent_calc_inline_size(newsize);
826 ret = btrfs_truncate_item(trans, root, path,
827 newsize, 1);
828 BUG_ON(ret);
829 }
830 delete:
831 if (del_item) {
832 ret = btrfs_del_item(trans, root, path);
833 if (ret)
834 goto error;
835 } else {
836 break;
837 }
838 btrfs_release_path(root, path);
839 if (found_extent) {
840 ret = btrfs_free_extent(trans, root, extent_start,
841 extent_num_bytes,
842 root_owner,
843 root_gen, inode->i_ino,
844 found_key.offset, 0);
845 BUG_ON(ret);
846 }
847 }
848 ret = 0;
849 error:
850 btrfs_release_path(root, path);
851 btrfs_free_path(path);
852 inode->i_sb->s_dirt = 1;
853 return ret;
854 }
855
856 static int btrfs_cow_one_page(struct inode *inode, struct page *page,
857 size_t zero_start)
858 {
859 char *kaddr;
860 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
861 struct btrfs_root *root = BTRFS_I(inode)->root;
862 u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
863 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
864 u64 existing_delalloc;
865 u64 delalloc_start;
866 int ret = 0;
867
868 WARN_ON(!PageLocked(page));
869 set_page_extent_mapped(page);
870
871 lock_extent(em_tree, page_start, page_end, GFP_NOFS);
872 delalloc_start = page_start;
873 existing_delalloc = count_range_bits(&BTRFS_I(inode)->extent_tree,
874 &delalloc_start, page_end,
875 PAGE_CACHE_SIZE, EXTENT_DELALLOC);
876 set_extent_delalloc(&BTRFS_I(inode)->extent_tree, page_start,
877 page_end, GFP_NOFS);
878
879 spin_lock(&root->fs_info->delalloc_lock);
880 root->fs_info->delalloc_bytes += PAGE_CACHE_SIZE - existing_delalloc;
881 spin_unlock(&root->fs_info->delalloc_lock);
882
883 if (zero_start != PAGE_CACHE_SIZE) {
884 kaddr = kmap(page);
885 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
886 flush_dcache_page(page);
887 kunmap(page);
888 }
889 set_page_dirty(page);
890 unlock_extent(em_tree, page_start, page_end, GFP_NOFS);
891
892 return ret;
893 }
894
895 /*
896 * taken from block_truncate_page, but does cow as it zeros out
897 * any bytes left in the last page in the file.
898 */
899 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
900 {
901 struct inode *inode = mapping->host;
902 struct btrfs_root *root = BTRFS_I(inode)->root;
903 u32 blocksize = root->sectorsize;
904 pgoff_t index = from >> PAGE_CACHE_SHIFT;
905 unsigned offset = from & (PAGE_CACHE_SIZE-1);
906 struct page *page;
907 int ret = 0;
908 u64 page_start;
909
910 if ((offset & (blocksize - 1)) == 0)
911 goto out;
912
913 ret = -ENOMEM;
914 page = grab_cache_page(mapping, index);
915 if (!page)
916 goto out;
917 if (!PageUptodate(page)) {
918 ret = btrfs_readpage(NULL, page);
919 lock_page(page);
920 if (!PageUptodate(page)) {
921 ret = -EIO;
922 goto out;
923 }
924 }
925 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
926
927 ret = btrfs_cow_one_page(inode, page, offset);
928
929 unlock_page(page);
930 page_cache_release(page);
931 out:
932 return ret;
933 }
934
935 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
936 {
937 struct inode *inode = dentry->d_inode;
938 int err;
939
940 err = inode_change_ok(inode, attr);
941 if (err)
942 return err;
943
944 if (S_ISREG(inode->i_mode) &&
945 attr->ia_valid & ATTR_SIZE && attr->ia_size > inode->i_size) {
946 struct btrfs_trans_handle *trans;
947 struct btrfs_root *root = BTRFS_I(inode)->root;
948 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
949
950 u64 mask = root->sectorsize - 1;
951 u64 pos = (inode->i_size + mask) & ~mask;
952 u64 block_end = attr->ia_size | mask;
953 u64 hole_size;
954 u64 alloc_hint = 0;
955
956 if (attr->ia_size <= pos)
957 goto out;
958
959 mutex_lock(&root->fs_info->fs_mutex);
960 err = btrfs_check_free_space(root, 1, 0);
961 mutex_unlock(&root->fs_info->fs_mutex);
962 if (err)
963 goto fail;
964
965 btrfs_truncate_page(inode->i_mapping, inode->i_size);
966
967 lock_extent(em_tree, pos, block_end, GFP_NOFS);
968 hole_size = (attr->ia_size - pos + mask) & ~mask;
969
970 mutex_lock(&root->fs_info->fs_mutex);
971 trans = btrfs_start_transaction(root, 1);
972 btrfs_set_trans_block_group(trans, inode);
973 err = btrfs_drop_extents(trans, root, inode,
974 pos, pos + hole_size, pos,
975 &alloc_hint);
976
977 if (alloc_hint != EXTENT_MAP_INLINE) {
978 err = btrfs_insert_file_extent(trans, root,
979 inode->i_ino,
980 pos, 0, 0, hole_size);
981 }
982 btrfs_end_transaction(trans, root);
983 mutex_unlock(&root->fs_info->fs_mutex);
984 unlock_extent(em_tree, pos, block_end, GFP_NOFS);
985 if (err)
986 return err;
987 }
988 out:
989 err = inode_setattr(inode, attr);
990 fail:
991 return err;
992 }
993 void btrfs_delete_inode(struct inode *inode)
994 {
995 struct btrfs_trans_handle *trans;
996 struct btrfs_root *root = BTRFS_I(inode)->root;
997 unsigned long nr;
998 int ret;
999
1000 truncate_inode_pages(&inode->i_data, 0);
1001 if (is_bad_inode(inode)) {
1002 goto no_delete;
1003 }
1004
1005 inode->i_size = 0;
1006 mutex_lock(&root->fs_info->fs_mutex);
1007 trans = btrfs_start_transaction(root, 1);
1008
1009 btrfs_set_trans_block_group(trans, inode);
1010 ret = btrfs_truncate_in_trans(trans, root, inode);
1011 if (ret)
1012 goto no_delete_lock;
1013 ret = btrfs_delete_xattrs(trans, root, inode);
1014 if (ret)
1015 goto no_delete_lock;
1016 ret = btrfs_free_inode(trans, root, inode);
1017 if (ret)
1018 goto no_delete_lock;
1019 nr = trans->blocks_used;
1020
1021 btrfs_end_transaction(trans, root);
1022 mutex_unlock(&root->fs_info->fs_mutex);
1023 btrfs_btree_balance_dirty(root, nr);
1024 btrfs_throttle(root);
1025 return;
1026
1027 no_delete_lock:
1028 nr = trans->blocks_used;
1029 btrfs_end_transaction(trans, root);
1030 mutex_unlock(&root->fs_info->fs_mutex);
1031 btrfs_btree_balance_dirty(root, nr);
1032 btrfs_throttle(root);
1033 no_delete:
1034 clear_inode(inode);
1035 }
1036
1037 /*
1038 * this returns the key found in the dir entry in the location pointer.
1039 * If no dir entries were found, location->objectid is 0.
1040 */
1041 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
1042 struct btrfs_key *location)
1043 {
1044 const char *name = dentry->d_name.name;
1045 int namelen = dentry->d_name.len;
1046 struct btrfs_dir_item *di;
1047 struct btrfs_path *path;
1048 struct btrfs_root *root = BTRFS_I(dir)->root;
1049 int ret = 0;
1050
1051 if (namelen == 1 && strcmp(name, ".") == 0) {
1052 location->objectid = dir->i_ino;
1053 location->type = BTRFS_INODE_ITEM_KEY;
1054 location->offset = 0;
1055 return 0;
1056 }
1057 path = btrfs_alloc_path();
1058 BUG_ON(!path);
1059
1060 if (namelen == 2 && strcmp(name, "..") == 0) {
1061 struct btrfs_key key;
1062 struct extent_buffer *leaf;
1063 u32 nritems;
1064 int slot;
1065
1066 key.objectid = dir->i_ino;
1067 btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
1068 key.offset = 0;
1069 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1070 BUG_ON(ret == 0);
1071 ret = 0;
1072
1073 leaf = path->nodes[0];
1074 slot = path->slots[0];
1075 nritems = btrfs_header_nritems(leaf);
1076 if (slot >= nritems)
1077 goto out_err;
1078
1079 btrfs_item_key_to_cpu(leaf, &key, slot);
1080 if (key.objectid != dir->i_ino ||
1081 key.type != BTRFS_INODE_REF_KEY) {
1082 goto out_err;
1083 }
1084 location->objectid = key.offset;
1085 location->type = BTRFS_INODE_ITEM_KEY;
1086 location->offset = 0;
1087 goto out;
1088 }
1089
1090 di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
1091 namelen, 0);
1092 if (IS_ERR(di))
1093 ret = PTR_ERR(di);
1094 if (!di || IS_ERR(di)) {
1095 goto out_err;
1096 }
1097 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
1098 out:
1099 btrfs_free_path(path);
1100 return ret;
1101 out_err:
1102 location->objectid = 0;
1103 goto out;
1104 }
1105
1106 /*
1107 * when we hit a tree root in a directory, the btrfs part of the inode
1108 * needs to be changed to reflect the root directory of the tree root. This
1109 * is kind of like crossing a mount point.
1110 */
1111 static int fixup_tree_root_location(struct btrfs_root *root,
1112 struct btrfs_key *location,
1113 struct btrfs_root **sub_root,
1114 struct dentry *dentry)
1115 {
1116 struct btrfs_path *path;
1117 struct btrfs_root_item *ri;
1118
1119 if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
1120 return 0;
1121 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1122 return 0;
1123
1124 path = btrfs_alloc_path();
1125 BUG_ON(!path);
1126 mutex_lock(&root->fs_info->fs_mutex);
1127
1128 *sub_root = btrfs_read_fs_root(root->fs_info, location,
1129 dentry->d_name.name,
1130 dentry->d_name.len);
1131 if (IS_ERR(*sub_root))
1132 return PTR_ERR(*sub_root);
1133
1134 ri = &(*sub_root)->root_item;
1135 location->objectid = btrfs_root_dirid(ri);
1136 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
1137 location->offset = 0;
1138
1139 btrfs_free_path(path);
1140 mutex_unlock(&root->fs_info->fs_mutex);
1141 return 0;
1142 }
1143
1144 static int btrfs_init_locked_inode(struct inode *inode, void *p)
1145 {
1146 struct btrfs_iget_args *args = p;
1147 inode->i_ino = args->ino;
1148 BTRFS_I(inode)->root = args->root;
1149 extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
1150 inode->i_mapping, GFP_NOFS);
1151 return 0;
1152 }
1153
1154 static int btrfs_find_actor(struct inode *inode, void *opaque)
1155 {
1156 struct btrfs_iget_args *args = opaque;
1157 return (args->ino == inode->i_ino &&
1158 args->root == BTRFS_I(inode)->root);
1159 }
1160
1161 struct inode *btrfs_ilookup(struct super_block *s, u64 objectid,
1162 u64 root_objectid)
1163 {
1164 struct btrfs_iget_args args;
1165 args.ino = objectid;
1166 args.root = btrfs_lookup_fs_root(btrfs_sb(s)->fs_info, root_objectid);
1167
1168 if (!args.root)
1169 return NULL;
1170
1171 return ilookup5(s, objectid, btrfs_find_actor, (void *)&args);
1172 }
1173
1174 struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
1175 struct btrfs_root *root)
1176 {
1177 struct inode *inode;
1178 struct btrfs_iget_args args;
1179 args.ino = objectid;
1180 args.root = root;
1181
1182 inode = iget5_locked(s, objectid, btrfs_find_actor,
1183 btrfs_init_locked_inode,
1184 (void *)&args);
1185 return inode;
1186 }
1187
1188 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
1189 struct nameidata *nd)
1190 {
1191 struct inode * inode;
1192 struct btrfs_inode *bi = BTRFS_I(dir);
1193 struct btrfs_root *root = bi->root;
1194 struct btrfs_root *sub_root = root;
1195 struct btrfs_key location;
1196 int ret;
1197
1198 if (dentry->d_name.len > BTRFS_NAME_LEN)
1199 return ERR_PTR(-ENAMETOOLONG);
1200
1201 mutex_lock(&root->fs_info->fs_mutex);
1202 ret = btrfs_inode_by_name(dir, dentry, &location);
1203 mutex_unlock(&root->fs_info->fs_mutex);
1204
1205 if (ret < 0)
1206 return ERR_PTR(ret);
1207
1208 inode = NULL;
1209 if (location.objectid) {
1210 ret = fixup_tree_root_location(root, &location, &sub_root,
1211 dentry);
1212 if (ret < 0)
1213 return ERR_PTR(ret);
1214 if (ret > 0)
1215 return ERR_PTR(-ENOENT);
1216 inode = btrfs_iget_locked(dir->i_sb, location.objectid,
1217 sub_root);
1218 if (!inode)
1219 return ERR_PTR(-EACCES);
1220 if (inode->i_state & I_NEW) {
1221 /* the inode and parent dir are two different roots */
1222 if (sub_root != root) {
1223 igrab(inode);
1224 sub_root->inode = inode;
1225 }
1226 BTRFS_I(inode)->root = sub_root;
1227 memcpy(&BTRFS_I(inode)->location, &location,
1228 sizeof(location));
1229 btrfs_read_locked_inode(inode);
1230 unlock_new_inode(inode);
1231 }
1232 }
1233 return d_splice_alias(inode, dentry);
1234 }
1235
1236 static unsigned char btrfs_filetype_table[] = {
1237 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
1238 };
1239
1240 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
1241 {
1242 struct inode *inode = filp->f_dentry->d_inode;
1243 struct btrfs_root *root = BTRFS_I(inode)->root;
1244 struct btrfs_item *item;
1245 struct btrfs_dir_item *di;
1246 struct btrfs_key key;
1247 struct btrfs_key found_key;
1248 struct btrfs_path *path;
1249 int ret;
1250 u32 nritems;
1251 struct extent_buffer *leaf;
1252 int slot;
1253 int advance;
1254 unsigned char d_type;
1255 int over = 0;
1256 u32 di_cur;
1257 u32 di_total;
1258 u32 di_len;
1259 int key_type = BTRFS_DIR_INDEX_KEY;
1260 char tmp_name[32];
1261 char *name_ptr;
1262 int name_len;
1263
1264 /* FIXME, use a real flag for deciding about the key type */
1265 if (root->fs_info->tree_root == root)
1266 key_type = BTRFS_DIR_ITEM_KEY;
1267
1268 /* special case for "." */
1269 if (filp->f_pos == 0) {
1270 over = filldir(dirent, ".", 1,
1271 1, inode->i_ino,
1272 DT_DIR);
1273 if (over)
1274 return 0;
1275 filp->f_pos = 1;
1276 }
1277
1278 mutex_lock(&root->fs_info->fs_mutex);
1279 key.objectid = inode->i_ino;
1280 path = btrfs_alloc_path();
1281 path->reada = 2;
1282
1283 /* special case for .., just use the back ref */
1284 if (filp->f_pos == 1) {
1285 btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
1286 key.offset = 0;
1287 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1288 BUG_ON(ret == 0);
1289 leaf = path->nodes[0];
1290 slot = path->slots[0];
1291 nritems = btrfs_header_nritems(leaf);
1292 if (slot >= nritems) {
1293 btrfs_release_path(root, path);
1294 goto read_dir_items;
1295 }
1296 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1297 btrfs_release_path(root, path);
1298 if (found_key.objectid != key.objectid ||
1299 found_key.type != BTRFS_INODE_REF_KEY)
1300 goto read_dir_items;
1301 over = filldir(dirent, "..", 2,
1302 2, found_key.offset, DT_DIR);
1303 if (over)
1304 goto nopos;
1305 filp->f_pos = 2;
1306 }
1307
1308 read_dir_items:
1309 btrfs_set_key_type(&key, key_type);
1310 key.offset = filp->f_pos;
1311
1312 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1313 if (ret < 0)
1314 goto err;
1315 advance = 0;
1316 while(1) {
1317 leaf = path->nodes[0];
1318 nritems = btrfs_header_nritems(leaf);
1319 slot = path->slots[0];
1320 if (advance || slot >= nritems) {
1321 if (slot >= nritems -1) {
1322 ret = btrfs_next_leaf(root, path);
1323 if (ret)
1324 break;
1325 leaf = path->nodes[0];
1326 nritems = btrfs_header_nritems(leaf);
1327 slot = path->slots[0];
1328 } else {
1329 slot++;
1330 path->slots[0]++;
1331 }
1332 }
1333 advance = 1;
1334 item = btrfs_item_nr(leaf, slot);
1335 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1336
1337 if (found_key.objectid != key.objectid)
1338 break;
1339 if (btrfs_key_type(&found_key) != key_type)
1340 break;
1341 if (found_key.offset < filp->f_pos)
1342 continue;
1343
1344 filp->f_pos = found_key.offset;
1345 advance = 1;
1346 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
1347 di_cur = 0;
1348 di_total = btrfs_item_size(leaf, item);
1349 while(di_cur < di_total) {
1350 struct btrfs_key location;
1351
1352 name_len = btrfs_dir_name_len(leaf, di);
1353 if (name_len < 32) {
1354 name_ptr = tmp_name;
1355 } else {
1356 name_ptr = kmalloc(name_len, GFP_NOFS);
1357 BUG_ON(!name_ptr);
1358 }
1359 read_extent_buffer(leaf, name_ptr,
1360 (unsigned long)(di + 1), name_len);
1361
1362 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
1363 btrfs_dir_item_key_to_cpu(leaf, di, &location);
1364 over = filldir(dirent, name_ptr, name_len,
1365 found_key.offset,
1366 location.objectid,
1367 d_type);
1368
1369 if (name_ptr != tmp_name)
1370 kfree(name_ptr);
1371
1372 if (over)
1373 goto nopos;
1374 di_len = btrfs_dir_name_len(leaf, di) +
1375 btrfs_dir_data_len(leaf, di) +sizeof(*di);
1376 di_cur += di_len;
1377 di = (struct btrfs_dir_item *)((char *)di + di_len);
1378 }
1379 }
1380 filp->f_pos++;
1381 nopos:
1382 ret = 0;
1383 err:
1384 btrfs_release_path(root, path);
1385 btrfs_free_path(path);
1386 mutex_unlock(&root->fs_info->fs_mutex);
1387 return ret;
1388 }
1389
1390 int btrfs_write_inode(struct inode *inode, int wait)
1391 {
1392 struct btrfs_root *root = BTRFS_I(inode)->root;
1393 struct btrfs_trans_handle *trans;
1394 int ret = 0;
1395
1396 if (wait) {
1397 mutex_lock(&root->fs_info->fs_mutex);
1398 trans = btrfs_start_transaction(root, 1);
1399 btrfs_set_trans_block_group(trans, inode);
1400 ret = btrfs_commit_transaction(trans, root);
1401 mutex_unlock(&root->fs_info->fs_mutex);
1402 }
1403 return ret;
1404 }
1405
1406 /*
1407 * This is somewhat expensive, updating the tree every time the
1408 * inode changes. But, it is most likely to find the inode in cache.
1409 * FIXME, needs more benchmarking...there are no reasons other than performance
1410 * to keep or drop this code.
1411 */
1412 void btrfs_dirty_inode(struct inode *inode)
1413 {
1414 struct btrfs_root *root = BTRFS_I(inode)->root;
1415 struct btrfs_trans_handle *trans;
1416
1417 mutex_lock(&root->fs_info->fs_mutex);
1418 trans = btrfs_start_transaction(root, 1);
1419 btrfs_set_trans_block_group(trans, inode);
1420 btrfs_update_inode(trans, root, inode);
1421 btrfs_end_transaction(trans, root);
1422 mutex_unlock(&root->fs_info->fs_mutex);
1423 }
1424
1425 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
1426 struct btrfs_root *root,
1427 u64 objectid,
1428 struct btrfs_block_group_cache *group,
1429 int mode)
1430 {
1431 struct inode *inode;
1432 struct btrfs_inode_item *inode_item;
1433 struct btrfs_key *location;
1434 struct btrfs_path *path;
1435 int ret;
1436 int owner;
1437
1438 path = btrfs_alloc_path();
1439 BUG_ON(!path);
1440
1441 inode = new_inode(root->fs_info->sb);
1442 if (!inode)
1443 return ERR_PTR(-ENOMEM);
1444
1445 extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
1446 inode->i_mapping, GFP_NOFS);
1447 BTRFS_I(inode)->root = root;
1448
1449 if (mode & S_IFDIR)
1450 owner = 0;
1451 else
1452 owner = 1;
1453 group = btrfs_find_block_group(root, group, 0, 0, owner);
1454 BTRFS_I(inode)->block_group = group;
1455 BTRFS_I(inode)->flags = 0;
1456 ret = btrfs_insert_empty_inode(trans, root, path, objectid);
1457 if (ret)
1458 goto fail;
1459
1460 inode->i_uid = current->fsuid;
1461 inode->i_gid = current->fsgid;
1462 inode->i_mode = mode;
1463 inode->i_ino = objectid;
1464 inode->i_blocks = 0;
1465 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1466 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1467 struct btrfs_inode_item);
1468 fill_inode_item(path->nodes[0], inode_item, inode);
1469 btrfs_mark_buffer_dirty(path->nodes[0]);
1470 btrfs_free_path(path);
1471
1472 location = &BTRFS_I(inode)->location;
1473 location->objectid = objectid;
1474 location->offset = 0;
1475 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
1476
1477 insert_inode_hash(inode);
1478 return inode;
1479 fail:
1480 btrfs_free_path(path);
1481 return ERR_PTR(ret);
1482 }
1483
1484 static inline u8 btrfs_inode_type(struct inode *inode)
1485 {
1486 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
1487 }
1488
1489 static int btrfs_add_link(struct btrfs_trans_handle *trans,
1490 struct dentry *dentry, struct inode *inode)
1491 {
1492 int ret;
1493 struct btrfs_key key;
1494 struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
1495 struct inode *parent_inode;
1496
1497 key.objectid = inode->i_ino;
1498 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
1499 key.offset = 0;
1500
1501 ret = btrfs_insert_dir_item(trans, root,
1502 dentry->d_name.name, dentry->d_name.len,
1503 dentry->d_parent->d_inode->i_ino,
1504 &key, btrfs_inode_type(inode));
1505 if (ret == 0) {
1506 ret = btrfs_insert_inode_ref(trans, root,
1507 dentry->d_name.name,
1508 dentry->d_name.len,
1509 inode->i_ino,
1510 dentry->d_parent->d_inode->i_ino);
1511 parent_inode = dentry->d_parent->d_inode;
1512 parent_inode->i_size += dentry->d_name.len * 2;
1513 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
1514 ret = btrfs_update_inode(trans, root,
1515 dentry->d_parent->d_inode);
1516 }
1517 return ret;
1518 }
1519
1520 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
1521 struct dentry *dentry, struct inode *inode)
1522 {
1523 int err = btrfs_add_link(trans, dentry, inode);
1524 if (!err) {
1525 d_instantiate(dentry, inode);
1526 return 0;
1527 }
1528 if (err > 0)
1529 err = -EEXIST;
1530 return err;
1531 }
1532
1533 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
1534 int mode, dev_t rdev)
1535 {
1536 struct btrfs_trans_handle *trans;
1537 struct btrfs_root *root = BTRFS_I(dir)->root;
1538 struct inode *inode = NULL;
1539 int err;
1540 int drop_inode = 0;
1541 u64 objectid;
1542 unsigned long nr = 0;
1543
1544 if (!new_valid_dev(rdev))
1545 return -EINVAL;
1546
1547 mutex_lock(&root->fs_info->fs_mutex);
1548 err = btrfs_check_free_space(root, 1, 0);
1549 if (err)
1550 goto fail;
1551
1552 trans = btrfs_start_transaction(root, 1);
1553 btrfs_set_trans_block_group(trans, dir);
1554
1555 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1556 if (err) {
1557 err = -ENOSPC;
1558 goto out_unlock;
1559 }
1560
1561 inode = btrfs_new_inode(trans, root, objectid,
1562 BTRFS_I(dir)->block_group, mode);
1563 err = PTR_ERR(inode);
1564 if (IS_ERR(inode))
1565 goto out_unlock;
1566
1567 btrfs_set_trans_block_group(trans, inode);
1568 err = btrfs_add_nondir(trans, dentry, inode);
1569 if (err)
1570 drop_inode = 1;
1571 else {
1572 inode->i_op = &btrfs_special_inode_operations;
1573 init_special_inode(inode, inode->i_mode, rdev);
1574 btrfs_update_inode(trans, root, inode);
1575 }
1576 dir->i_sb->s_dirt = 1;
1577 btrfs_update_inode_block_group(trans, inode);
1578 btrfs_update_inode_block_group(trans, dir);
1579 out_unlock:
1580 nr = trans->blocks_used;
1581 btrfs_end_transaction(trans, root);
1582 fail:
1583 mutex_unlock(&root->fs_info->fs_mutex);
1584
1585 if (drop_inode) {
1586 inode_dec_link_count(inode);
1587 iput(inode);
1588 }
1589 btrfs_btree_balance_dirty(root, nr);
1590 btrfs_throttle(root);
1591 return err;
1592 }
1593
1594 static int btrfs_create(struct inode *dir, struct dentry *dentry,
1595 int mode, struct nameidata *nd)
1596 {
1597 struct btrfs_trans_handle *trans;
1598 struct btrfs_root *root = BTRFS_I(dir)->root;
1599 struct inode *inode = NULL;
1600 int err;
1601 int drop_inode = 0;
1602 unsigned long nr = 0;
1603 u64 objectid;
1604
1605 mutex_lock(&root->fs_info->fs_mutex);
1606 err = btrfs_check_free_space(root, 1, 0);
1607 if (err)
1608 goto fail;
1609 trans = btrfs_start_transaction(root, 1);
1610 btrfs_set_trans_block_group(trans, dir);
1611
1612 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1613 if (err) {
1614 err = -ENOSPC;
1615 goto out_unlock;
1616 }
1617
1618 inode = btrfs_new_inode(trans, root, objectid,
1619 BTRFS_I(dir)->block_group, mode);
1620 err = PTR_ERR(inode);
1621 if (IS_ERR(inode))
1622 goto out_unlock;
1623
1624 btrfs_set_trans_block_group(trans, inode);
1625 err = btrfs_add_nondir(trans, dentry, inode);
1626 if (err)
1627 drop_inode = 1;
1628 else {
1629 inode->i_mapping->a_ops = &btrfs_aops;
1630 inode->i_fop = &btrfs_file_operations;
1631 inode->i_op = &btrfs_file_inode_operations;
1632 extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
1633 inode->i_mapping, GFP_NOFS);
1634 BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
1635 }
1636 dir->i_sb->s_dirt = 1;
1637 btrfs_update_inode_block_group(trans, inode);
1638 btrfs_update_inode_block_group(trans, dir);
1639 out_unlock:
1640 nr = trans->blocks_used;
1641 btrfs_end_transaction(trans, root);
1642 fail:
1643 mutex_unlock(&root->fs_info->fs_mutex);
1644
1645 if (drop_inode) {
1646 inode_dec_link_count(inode);
1647 iput(inode);
1648 }
1649 btrfs_btree_balance_dirty(root, nr);
1650 btrfs_throttle(root);
1651 return err;
1652 }
1653
1654 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
1655 struct dentry *dentry)
1656 {
1657 struct btrfs_trans_handle *trans;
1658 struct btrfs_root *root = BTRFS_I(dir)->root;
1659 struct inode *inode = old_dentry->d_inode;
1660 unsigned long nr = 0;
1661 int err;
1662 int drop_inode = 0;
1663
1664 if (inode->i_nlink == 0)
1665 return -ENOENT;
1666
1667 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
1668 inode->i_nlink++;
1669 #else
1670 inc_nlink(inode);
1671 #endif
1672 mutex_lock(&root->fs_info->fs_mutex);
1673 err = btrfs_check_free_space(root, 1, 0);
1674 if (err)
1675 goto fail;
1676 trans = btrfs_start_transaction(root, 1);
1677
1678 btrfs_set_trans_block_group(trans, dir);
1679 atomic_inc(&inode->i_count);
1680 err = btrfs_add_nondir(trans, dentry, inode);
1681
1682 if (err)
1683 drop_inode = 1;
1684
1685 dir->i_sb->s_dirt = 1;
1686 btrfs_update_inode_block_group(trans, dir);
1687 err = btrfs_update_inode(trans, root, inode);
1688
1689 if (err)
1690 drop_inode = 1;
1691
1692 nr = trans->blocks_used;
1693 btrfs_end_transaction(trans, root);
1694 fail:
1695 mutex_unlock(&root->fs_info->fs_mutex);
1696
1697 if (drop_inode) {
1698 inode_dec_link_count(inode);
1699 iput(inode);
1700 }
1701 btrfs_btree_balance_dirty(root, nr);
1702 btrfs_throttle(root);
1703 return err;
1704 }
1705
1706 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
1707 {
1708 struct inode *inode;
1709 struct btrfs_trans_handle *trans;
1710 struct btrfs_root *root = BTRFS_I(dir)->root;
1711 int err = 0;
1712 int drop_on_err = 0;
1713 u64 objectid;
1714 unsigned long nr = 1;
1715
1716 mutex_lock(&root->fs_info->fs_mutex);
1717 err = btrfs_check_free_space(root, 1, 0);
1718 if (err)
1719 goto out_unlock;
1720
1721 trans = btrfs_start_transaction(root, 1);
1722 btrfs_set_trans_block_group(trans, dir);
1723
1724 if (IS_ERR(trans)) {
1725 err = PTR_ERR(trans);
1726 goto out_unlock;
1727 }
1728
1729 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1730 if (err) {
1731 err = -ENOSPC;
1732 goto out_unlock;
1733 }
1734
1735 inode = btrfs_new_inode(trans, root, objectid,
1736 BTRFS_I(dir)->block_group, S_IFDIR | mode);
1737 if (IS_ERR(inode)) {
1738 err = PTR_ERR(inode);
1739 goto out_fail;
1740 }
1741
1742 drop_on_err = 1;
1743 inode->i_op = &btrfs_dir_inode_operations;
1744 inode->i_fop = &btrfs_dir_file_operations;
1745 btrfs_set_trans_block_group(trans, inode);
1746
1747 inode->i_size = 0;
1748 err = btrfs_update_inode(trans, root, inode);
1749 if (err)
1750 goto out_fail;
1751
1752 err = btrfs_add_link(trans, dentry, inode);
1753 if (err)
1754 goto out_fail;
1755
1756 d_instantiate(dentry, inode);
1757 drop_on_err = 0;
1758 dir->i_sb->s_dirt = 1;
1759 btrfs_update_inode_block_group(trans, inode);
1760 btrfs_update_inode_block_group(trans, dir);
1761
1762 out_fail:
1763 nr = trans->blocks_used;
1764 btrfs_end_transaction(trans, root);
1765
1766 out_unlock:
1767 mutex_unlock(&root->fs_info->fs_mutex);
1768 if (drop_on_err)
1769 iput(inode);
1770 btrfs_btree_balance_dirty(root, nr);
1771 btrfs_throttle(root);
1772 return err;
1773 }
1774
1775 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
1776 size_t page_offset, u64 start, u64 end,
1777 int create)
1778 {
1779 int ret;
1780 int err = 0;
1781 u64 bytenr;
1782 u64 extent_start = 0;
1783 u64 extent_end = 0;
1784 u64 objectid = inode->i_ino;
1785 u32 found_type;
1786 int failed_insert = 0;
1787 struct btrfs_path *path;
1788 struct btrfs_root *root = BTRFS_I(inode)->root;
1789 struct btrfs_file_extent_item *item;
1790 struct extent_buffer *leaf;
1791 struct btrfs_key found_key;
1792 struct extent_map *em = NULL;
1793 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1794 struct btrfs_trans_handle *trans = NULL;
1795
1796 path = btrfs_alloc_path();
1797 BUG_ON(!path);
1798 mutex_lock(&root->fs_info->fs_mutex);
1799
1800 again:
1801 em = lookup_extent_mapping(em_tree, start, end);
1802 if (em) {
1803 if (em->start > start) {
1804 printk("get_extent start %Lu em start %Lu\n",
1805 start, em->start);
1806 WARN_ON(1);
1807 }
1808 goto out;
1809 }
1810 if (!em) {
1811 em = alloc_extent_map(GFP_NOFS);
1812 if (!em) {
1813 err = -ENOMEM;
1814 goto out;
1815 }
1816 em->start = EXTENT_MAP_HOLE;
1817 em->end = EXTENT_MAP_HOLE;
1818 }
1819 em->bdev = inode->i_sb->s_bdev;
1820 ret = btrfs_lookup_file_extent(trans, root, path,
1821 objectid, start, trans != NULL);
1822 if (ret < 0) {
1823 err = ret;
1824 goto out;
1825 }
1826
1827 if (ret != 0) {
1828 if (path->slots[0] == 0)
1829 goto not_found;
1830 path->slots[0]--;
1831 }
1832
1833 leaf = path->nodes[0];
1834 item = btrfs_item_ptr(leaf, path->slots[0],
1835 struct btrfs_file_extent_item);
1836 /* are we inside the extent that was found? */
1837 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1838 found_type = btrfs_key_type(&found_key);
1839 if (found_key.objectid != objectid ||
1840 found_type != BTRFS_EXTENT_DATA_KEY) {
1841 goto not_found;
1842 }
1843
1844 found_type = btrfs_file_extent_type(leaf, item);
1845 extent_start = found_key.offset;
1846 if (found_type == BTRFS_FILE_EXTENT_REG) {
1847 extent_end = extent_start +
1848 btrfs_file_extent_num_bytes(leaf, item);
1849 err = 0;
1850 if (start < extent_start || start >= extent_end) {
1851 em->start = start;
1852 if (start < extent_start) {
1853 if (end < extent_start)
1854 goto not_found;
1855 em->end = extent_end - 1;
1856 } else {
1857 em->end = end;
1858 }
1859 goto not_found_em;
1860 }
1861 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
1862 if (bytenr == 0) {
1863 em->start = extent_start;
1864 em->end = extent_end - 1;
1865 em->block_start = EXTENT_MAP_HOLE;
1866 em->block_end = EXTENT_MAP_HOLE;
1867 goto insert;
1868 }
1869 bytenr += btrfs_file_extent_offset(leaf, item);
1870 em->block_start = bytenr;
1871 em->block_end = em->block_start +
1872 btrfs_file_extent_num_bytes(leaf, item) - 1;
1873 em->start = extent_start;
1874 em->end = extent_end - 1;
1875 goto insert;
1876 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
1877 unsigned long ptr;
1878 char *map;
1879 size_t size;
1880 size_t extent_offset;
1881 size_t copy_size;
1882
1883 size = btrfs_file_extent_inline_len(leaf, btrfs_item_nr(leaf,
1884 path->slots[0]));
1885 extent_end = (extent_start + size - 1) |
1886 ((u64)root->sectorsize - 1);
1887 if (start < extent_start || start >= extent_end) {
1888 em->start = start;
1889 if (start < extent_start) {
1890 if (end < extent_start)
1891 goto not_found;
1892 em->end = extent_end;
1893 } else {
1894 em->end = end;
1895 }
1896 goto not_found_em;
1897 }
1898 em->block_start = EXTENT_MAP_INLINE;
1899 em->block_end = EXTENT_MAP_INLINE;
1900
1901 if (!page) {
1902 em->start = extent_start;
1903 em->end = extent_start + size - 1;
1904 goto out;
1905 }
1906
1907 extent_offset = ((u64)page->index << PAGE_CACHE_SHIFT) -
1908 extent_start + page_offset;
1909 copy_size = min_t(u64, PAGE_CACHE_SIZE - page_offset,
1910 size - extent_offset);
1911 em->start = extent_start + extent_offset;
1912 em->end = (em->start + copy_size -1) |
1913 ((u64)root->sectorsize -1);
1914 map = kmap(page);
1915 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
1916 if (create == 0 && !PageUptodate(page)) {
1917 read_extent_buffer(leaf, map + page_offset, ptr,
1918 copy_size);
1919 flush_dcache_page(page);
1920 } else if (create && PageUptodate(page)) {
1921 if (!trans) {
1922 kunmap(page);
1923 free_extent_map(em);
1924 em = NULL;
1925 btrfs_release_path(root, path);
1926 trans = btrfs_start_transaction(root, 1);
1927 goto again;
1928 }
1929 write_extent_buffer(leaf, map + page_offset, ptr,
1930 copy_size);
1931 btrfs_mark_buffer_dirty(leaf);
1932 }
1933 kunmap(page);
1934 set_extent_uptodate(em_tree, em->start, em->end, GFP_NOFS);
1935 goto insert;
1936 } else {
1937 printk("unkknown found_type %d\n", found_type);
1938 WARN_ON(1);
1939 }
1940 not_found:
1941 em->start = start;
1942 em->end = end;
1943 not_found_em:
1944 em->block_start = EXTENT_MAP_HOLE;
1945 em->block_end = EXTENT_MAP_HOLE;
1946 insert:
1947 btrfs_release_path(root, path);
1948 if (em->start > start || em->end < start) {
1949 printk("bad extent! em: [%Lu %Lu] passed [%Lu %Lu]\n", em->start, em->end, start, end);
1950 err = -EIO;
1951 goto out;
1952 }
1953 ret = add_extent_mapping(em_tree, em);
1954 if (ret == -EEXIST) {
1955 free_extent_map(em);
1956 em = NULL;
1957 if (0 && failed_insert == 1) {
1958 btrfs_drop_extent_cache(inode, start, end);
1959 }
1960 failed_insert++;
1961 if (failed_insert > 5) {
1962 printk("failing to insert %Lu %Lu\n", start, end);
1963 err = -EIO;
1964 goto out;
1965 }
1966 goto again;
1967 }
1968 err = 0;
1969 out:
1970 btrfs_free_path(path);
1971 if (trans) {
1972 ret = btrfs_end_transaction(trans, root);
1973 if (!err)
1974 err = ret;
1975 }
1976 mutex_unlock(&root->fs_info->fs_mutex);
1977 if (err) {
1978 free_extent_map(em);
1979 WARN_ON(1);
1980 return ERR_PTR(err);
1981 }
1982 return em;
1983 }
1984
1985 static sector_t btrfs_bmap(struct address_space *mapping, sector_t iblock)
1986 {
1987 return extent_bmap(mapping, iblock, btrfs_get_extent);
1988 }
1989
1990 int btrfs_readpage(struct file *file, struct page *page)
1991 {
1992 struct extent_map_tree *tree;
1993 tree = &BTRFS_I(page->mapping->host)->extent_tree;
1994 return extent_read_full_page(tree, page, btrfs_get_extent);
1995 }
1996
1997 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
1998 {
1999 struct extent_map_tree *tree;
2000
2001
2002 if (current->flags & PF_MEMALLOC) {
2003 redirty_page_for_writepage(wbc, page);
2004 unlock_page(page);
2005 return 0;
2006 }
2007 tree = &BTRFS_I(page->mapping->host)->extent_tree;
2008 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
2009 }
2010
2011 static int btrfs_writepages(struct address_space *mapping,
2012 struct writeback_control *wbc)
2013 {
2014 struct extent_map_tree *tree;
2015 tree = &BTRFS_I(mapping->host)->extent_tree;
2016 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
2017 }
2018
2019 static int
2020 btrfs_readpages(struct file *file, struct address_space *mapping,
2021 struct list_head *pages, unsigned nr_pages)
2022 {
2023 struct extent_map_tree *tree;
2024 tree = &BTRFS_I(mapping->host)->extent_tree;
2025 return extent_readpages(tree, mapping, pages, nr_pages,
2026 btrfs_get_extent);
2027 }
2028
2029 static int btrfs_releasepage(struct page *page, gfp_t unused_gfp_flags)
2030 {
2031 struct extent_map_tree *tree;
2032 int ret;
2033
2034 tree = &BTRFS_I(page->mapping->host)->extent_tree;
2035 ret = try_release_extent_mapping(tree, page);
2036 if (ret == 1) {
2037 ClearPagePrivate(page);
2038 set_page_private(page, 0);
2039 page_cache_release(page);
2040 }
2041 return ret;
2042 }
2043
2044 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
2045 {
2046 struct extent_map_tree *tree;
2047
2048 tree = &BTRFS_I(page->mapping->host)->extent_tree;
2049 extent_invalidatepage(tree, page, offset);
2050 btrfs_releasepage(page, GFP_NOFS);
2051 }
2052
2053 /*
2054 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
2055 * called from a page fault handler when a page is first dirtied. Hence we must
2056 * be careful to check for EOF conditions here. We set the page up correctly
2057 * for a written page which means we get ENOSPC checking when writing into
2058 * holes and correct delalloc and unwritten extent mapping on filesystems that
2059 * support these features.
2060 *
2061 * We are not allowed to take the i_mutex here so we have to play games to
2062 * protect against truncate races as the page could now be beyond EOF. Because
2063 * vmtruncate() writes the inode size before removing pages, once we have the
2064 * page lock we can determine safely if the page is beyond EOF. If it is not
2065 * beyond EOF, then the page is guaranteed safe against truncation until we
2066 * unlock the page.
2067 */
2068 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
2069 {
2070 struct inode *inode = fdentry(vma->vm_file)->d_inode;
2071 struct btrfs_root *root = BTRFS_I(inode)->root;
2072 unsigned long end;
2073 loff_t size;
2074 int ret;
2075 u64 page_start;
2076
2077 mutex_lock(&root->fs_info->fs_mutex);
2078 ret = btrfs_check_free_space(root, PAGE_CACHE_SIZE, 0);
2079 mutex_unlock(&root->fs_info->fs_mutex);
2080 if (ret)
2081 goto out;
2082
2083 ret = -EINVAL;
2084
2085 lock_page(page);
2086 wait_on_page_writeback(page);
2087 size = i_size_read(inode);
2088 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2089
2090 if ((page->mapping != inode->i_mapping) ||
2091 (page_start > size)) {
2092 /* page got truncated out from underneath us */
2093 goto out_unlock;
2094 }
2095
2096 /* page is wholly or partially inside EOF */
2097 if (page_start + PAGE_CACHE_SIZE > size)
2098 end = size & ~PAGE_CACHE_MASK;
2099 else
2100 end = PAGE_CACHE_SIZE;
2101
2102 ret = btrfs_cow_one_page(inode, page, end);
2103
2104 out_unlock:
2105 unlock_page(page);
2106 out:
2107 return ret;
2108 }
2109
2110 static void btrfs_truncate(struct inode *inode)
2111 {
2112 struct btrfs_root *root = BTRFS_I(inode)->root;
2113 int ret;
2114 struct btrfs_trans_handle *trans;
2115 unsigned long nr;
2116
2117 if (!S_ISREG(inode->i_mode))
2118 return;
2119 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
2120 return;
2121
2122 btrfs_truncate_page(inode->i_mapping, inode->i_size);
2123
2124 mutex_lock(&root->fs_info->fs_mutex);
2125 trans = btrfs_start_transaction(root, 1);
2126 btrfs_set_trans_block_group(trans, inode);
2127
2128 /* FIXME, add redo link to tree so we don't leak on crash */
2129 ret = btrfs_truncate_in_trans(trans, root, inode);
2130 btrfs_update_inode(trans, root, inode);
2131 nr = trans->blocks_used;
2132
2133 ret = btrfs_end_transaction(trans, root);
2134 BUG_ON(ret);
2135 mutex_unlock(&root->fs_info->fs_mutex);
2136 btrfs_btree_balance_dirty(root, nr);
2137 btrfs_throttle(root);
2138 }
2139
2140 static int noinline create_subvol(struct btrfs_root *root, char *name,
2141 int namelen)
2142 {
2143 struct btrfs_trans_handle *trans;
2144 struct btrfs_key key;
2145 struct btrfs_root_item root_item;
2146 struct btrfs_inode_item *inode_item;
2147 struct extent_buffer *leaf;
2148 struct btrfs_root *new_root = root;
2149 struct inode *inode;
2150 struct inode *dir;
2151 int ret;
2152 int err;
2153 u64 objectid;
2154 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
2155 unsigned long nr = 1;
2156
2157 mutex_lock(&root->fs_info->fs_mutex);
2158 ret = btrfs_check_free_space(root, 1, 0);
2159 if (ret)
2160 goto fail_commit;
2161
2162 trans = btrfs_start_transaction(root, 1);
2163 BUG_ON(!trans);
2164
2165 ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
2166 0, &objectid);
2167 if (ret)
2168 goto fail;
2169
2170 leaf = __btrfs_alloc_free_block(trans, root, root->leafsize,
2171 objectid, trans->transid, 0, 0,
2172 0, 0);
2173 if (IS_ERR(leaf))
2174 return PTR_ERR(leaf);
2175
2176 btrfs_set_header_nritems(leaf, 0);
2177 btrfs_set_header_level(leaf, 0);
2178 btrfs_set_header_bytenr(leaf, leaf->start);
2179 btrfs_set_header_generation(leaf, trans->transid);
2180 btrfs_set_header_owner(leaf, objectid);
2181
2182 write_extent_buffer(leaf, root->fs_info->fsid,
2183 (unsigned long)btrfs_header_fsid(leaf),
2184 BTRFS_FSID_SIZE);
2185 btrfs_mark_buffer_dirty(leaf);
2186
2187 inode_item = &root_item.inode;
2188 memset(inode_item, 0, sizeof(*inode_item));
2189 inode_item->generation = cpu_to_le64(1);
2190 inode_item->size = cpu_to_le64(3);
2191 inode_item->nlink = cpu_to_le32(1);
2192 inode_item->nblocks = cpu_to_le64(1);
2193 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
2194
2195 btrfs_set_root_bytenr(&root_item, leaf->start);
2196 btrfs_set_root_level(&root_item, 0);
2197 btrfs_set_root_refs(&root_item, 1);
2198 btrfs_set_root_used(&root_item, 0);
2199
2200 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
2201 root_item.drop_level = 0;
2202
2203 free_extent_buffer(leaf);
2204 leaf = NULL;
2205
2206 btrfs_set_root_dirid(&root_item, new_dirid);
2207
2208 key.objectid = objectid;
2209 key.offset = 1;
2210 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
2211 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
2212 &root_item);
2213 if (ret)
2214 goto fail;
2215
2216 /*
2217 * insert the directory item
2218 */
2219 key.offset = (u64)-1;
2220 dir = root->fs_info->sb->s_root->d_inode;
2221 ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
2222 name, namelen, dir->i_ino, &key,
2223 BTRFS_FT_DIR);
2224 if (ret)
2225 goto fail;
2226
2227 ret = btrfs_insert_inode_ref(trans, root->fs_info->tree_root,
2228 name, namelen, objectid,
2229 root->fs_info->sb->s_root->d_inode->i_ino);
2230 if (ret)
2231 goto fail;
2232
2233 ret = btrfs_commit_transaction(trans, root);
2234 if (ret)
2235 goto fail_commit;
2236
2237 new_root = btrfs_read_fs_root(root->fs_info, &key, name, namelen);
2238 BUG_ON(!new_root);
2239
2240 trans = btrfs_start_transaction(new_root, 1);
2241 BUG_ON(!trans);
2242
2243 inode = btrfs_new_inode(trans, new_root, new_dirid,
2244 BTRFS_I(dir)->block_group, S_IFDIR | 0700);
2245 if (IS_ERR(inode))
2246 goto fail;
2247 inode->i_op = &btrfs_dir_inode_operations;
2248 inode->i_fop = &btrfs_dir_file_operations;
2249 new_root->inode = inode;
2250
2251 ret = btrfs_insert_inode_ref(trans, new_root, "..", 2, new_dirid,
2252 new_dirid);
2253 inode->i_nlink = 1;
2254 inode->i_size = 0;
2255 ret = btrfs_update_inode(trans, new_root, inode);
2256 if (ret)
2257 goto fail;
2258 fail:
2259 nr = trans->blocks_used;
2260 err = btrfs_commit_transaction(trans, new_root);
2261 if (err && !ret)
2262 ret = err;
2263 fail_commit:
2264 mutex_unlock(&root->fs_info->fs_mutex);
2265 btrfs_btree_balance_dirty(root, nr);
2266 btrfs_throttle(root);
2267 return ret;
2268 }
2269
2270 static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
2271 {
2272 struct btrfs_pending_snapshot *pending_snapshot;
2273 struct btrfs_trans_handle *trans;
2274 int ret;
2275 int err;
2276 unsigned long nr = 0;
2277
2278 if (!root->ref_cows)
2279 return -EINVAL;
2280
2281 mutex_lock(&root->fs_info->fs_mutex);
2282 ret = btrfs_check_free_space(root, 1, 0);
2283 if (ret)
2284 goto fail_unlock;
2285
2286 pending_snapshot = kmalloc(sizeof(*pending_snapshot), GFP_NOFS);
2287 if (!pending_snapshot) {
2288 ret = -ENOMEM;
2289 goto fail_unlock;
2290 }
2291 pending_snapshot->name = kstrndup(name, namelen, GFP_NOFS);
2292 if (!pending_snapshot->name) {
2293 ret = -ENOMEM;
2294 kfree(pending_snapshot);
2295 goto fail_unlock;
2296 }
2297 trans = btrfs_start_transaction(root, 1);
2298 BUG_ON(!trans);
2299
2300 pending_snapshot->root = root;
2301 list_add(&pending_snapshot->list,
2302 &trans->transaction->pending_snapshots);
2303 ret = btrfs_update_inode(trans, root, root->inode);
2304 err = btrfs_commit_transaction(trans, root);
2305
2306 fail_unlock:
2307 mutex_unlock(&root->fs_info->fs_mutex);
2308 btrfs_btree_balance_dirty(root, nr);
2309 btrfs_throttle(root);
2310 return ret;
2311 }
2312
2313 unsigned long btrfs_force_ra(struct address_space *mapping,
2314 struct file_ra_state *ra, struct file *file,
2315 pgoff_t offset, pgoff_t last_index)
2316 {
2317 pgoff_t req_size;
2318
2319 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
2320 req_size = last_index - offset + 1;
2321 offset = page_cache_readahead(mapping, ra, file, offset, req_size);
2322 return offset;
2323 #else
2324 req_size = min(last_index - offset + 1, (pgoff_t)128);
2325 page_cache_sync_readahead(mapping, ra, file, offset, req_size);
2326 return offset + req_size;
2327 #endif
2328 }
2329
2330 int btrfs_defrag_file(struct file *file) {
2331 struct inode *inode = fdentry(file)->d_inode;
2332 struct btrfs_root *root = BTRFS_I(inode)->root;
2333 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
2334 struct page *page;
2335 unsigned long last_index;
2336 unsigned long ra_index = 0;
2337 u64 page_start;
2338 u64 page_end;
2339 u64 delalloc_start;
2340 u64 existing_delalloc;
2341 unsigned long i;
2342 int ret;
2343
2344 mutex_lock(&root->fs_info->fs_mutex);
2345 ret = btrfs_check_free_space(root, inode->i_size, 0);
2346 mutex_unlock(&root->fs_info->fs_mutex);
2347 if (ret)
2348 return -ENOSPC;
2349
2350 mutex_lock(&inode->i_mutex);
2351 last_index = inode->i_size >> PAGE_CACHE_SHIFT;
2352 for (i = 0; i <= last_index; i++) {
2353 if (i == ra_index) {
2354 ra_index = btrfs_force_ra(inode->i_mapping,
2355 &file->f_ra,
2356 file, ra_index, last_index);
2357 }
2358 page = grab_cache_page(inode->i_mapping, i);
2359 if (!page)
2360 goto out_unlock;
2361 if (!PageUptodate(page)) {
2362 btrfs_readpage(NULL, page);
2363 lock_page(page);
2364 if (!PageUptodate(page)) {
2365 unlock_page(page);
2366 page_cache_release(page);
2367 goto out_unlock;
2368 }
2369 }
2370 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2371 page_end = page_start + PAGE_CACHE_SIZE - 1;
2372
2373 lock_extent(em_tree, page_start, page_end, GFP_NOFS);
2374 delalloc_start = page_start;
2375 existing_delalloc =
2376 count_range_bits(&BTRFS_I(inode)->extent_tree,
2377 &delalloc_start, page_end,
2378 PAGE_CACHE_SIZE, EXTENT_DELALLOC);
2379 set_extent_delalloc(em_tree, page_start,
2380 page_end, GFP_NOFS);
2381
2382 spin_lock(&root->fs_info->delalloc_lock);
2383 root->fs_info->delalloc_bytes += PAGE_CACHE_SIZE -
2384 existing_delalloc;
2385 spin_unlock(&root->fs_info->delalloc_lock);
2386
2387 unlock_extent(em_tree, page_start, page_end, GFP_NOFS);
2388 set_page_dirty(page);
2389 unlock_page(page);
2390 page_cache_release(page);
2391 balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);
2392 }
2393
2394 out_unlock:
2395 mutex_unlock(&inode->i_mutex);
2396 return 0;
2397 }
2398
2399 static int btrfs_ioctl_resize(struct btrfs_root *root, void __user *arg)
2400 {
2401 u64 new_size;
2402 u64 old_size;
2403 struct btrfs_ioctl_vol_args *vol_args;
2404 struct btrfs_trans_handle *trans;
2405 char *sizestr;
2406 int ret = 0;
2407 int namelen;
2408 int mod = 0;
2409
2410 vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS);
2411
2412 if (!vol_args)
2413 return -ENOMEM;
2414
2415 if (copy_from_user(vol_args, arg, sizeof(*vol_args))) {
2416 ret = -EFAULT;
2417 goto out;
2418 }
2419 namelen = strlen(vol_args->name);
2420 if (namelen > BTRFS_VOL_NAME_MAX) {
2421 ret = -EINVAL;
2422 goto out;
2423 }
2424
2425 sizestr = vol_args->name;
2426 if (!strcmp(sizestr, "max"))
2427 new_size = root->fs_info->sb->s_bdev->bd_inode->i_size;
2428 else {
2429 if (sizestr[0] == '-') {
2430 mod = -1;
2431 sizestr++;
2432 } else if (sizestr[0] == '+') {
2433 mod = 1;
2434 sizestr++;
2435 }
2436 new_size = btrfs_parse_size(sizestr);
2437 if (new_size == 0) {
2438 ret = -EINVAL;
2439 goto out;
2440 }
2441 }
2442
2443 mutex_lock(&root->fs_info->fs_mutex);
2444 old_size = btrfs_super_total_bytes(&root->fs_info->super_copy);
2445
2446 if (mod < 0) {
2447 if (new_size > old_size) {
2448 ret = -EINVAL;
2449 goto out_unlock;
2450 }
2451 new_size = old_size - new_size;
2452 } else if (mod > 0) {
2453 new_size = old_size + new_size;
2454 }
2455
2456 if (new_size < 256 * 1024 * 1024) {
2457 ret = -EINVAL;
2458 goto out_unlock;
2459 }
2460 if (new_size > root->fs_info->sb->s_bdev->bd_inode->i_size) {
2461 ret = -EFBIG;
2462 goto out_unlock;
2463 }
2464
2465 do_div(new_size, root->sectorsize);
2466 new_size *= root->sectorsize;
2467
2468 printk("new size is %Lu\n", new_size);
2469 if (new_size > old_size) {
2470 trans = btrfs_start_transaction(root, 1);
2471 ret = btrfs_grow_extent_tree(trans, root, new_size);
2472 btrfs_commit_transaction(trans, root);
2473 } else {
2474 ret = btrfs_shrink_extent_tree(root, new_size);
2475 }
2476
2477 out_unlock:
2478 mutex_unlock(&root->fs_info->fs_mutex);
2479 out:
2480 kfree(vol_args);
2481 return ret;
2482 }
2483
2484 static int noinline btrfs_ioctl_snap_create(struct btrfs_root *root,
2485 void __user *arg)
2486 {
2487 struct btrfs_ioctl_vol_args *vol_args;
2488 struct btrfs_dir_item *di;
2489 struct btrfs_path *path;
2490 u64 root_dirid;
2491 int namelen;
2492 int ret;
2493
2494 vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS);
2495
2496 if (!vol_args)
2497 return -ENOMEM;
2498
2499 if (copy_from_user(vol_args, arg, sizeof(*vol_args))) {
2500 ret = -EFAULT;
2501 goto out;
2502 }
2503
2504 namelen = strlen(vol_args->name);
2505 if (namelen > BTRFS_VOL_NAME_MAX) {
2506 ret = -EINVAL;
2507 goto out;
2508 }
2509 if (strchr(vol_args->name, '/')) {
2510 ret = -EINVAL;
2511 goto out;
2512 }
2513
2514 path = btrfs_alloc_path();
2515 if (!path) {
2516 ret = -ENOMEM;
2517 goto out;
2518 }
2519
2520 root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
2521 mutex_lock(&root->fs_info->fs_mutex);
2522 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
2523 path, root_dirid,
2524 vol_args->name, namelen, 0);
2525 mutex_unlock(&root->fs_info->fs_mutex);
2526 btrfs_free_path(path);
2527
2528 if (di && !IS_ERR(di)) {
2529 ret = -EEXIST;
2530 goto out;
2531 }
2532
2533 if (IS_ERR(di)) {
2534 ret = PTR_ERR(di);
2535 goto out;
2536 }
2537
2538 if (root == root->fs_info->tree_root)
2539 ret = create_subvol(root, vol_args->name, namelen);
2540 else
2541 ret = create_snapshot(root, vol_args->name, namelen);
2542 out:
2543 kfree(vol_args);
2544 return ret;
2545 }
2546
2547 static int btrfs_ioctl_defrag(struct file *file)
2548 {
2549 struct inode *inode = fdentry(file)->d_inode;
2550 struct btrfs_root *root = BTRFS_I(inode)->root;
2551
2552 switch (inode->i_mode & S_IFMT) {
2553 case S_IFDIR:
2554 mutex_lock(&root->fs_info->fs_mutex);
2555 btrfs_defrag_root(root, 0);
2556 btrfs_defrag_root(root->fs_info->extent_root, 0);
2557 mutex_unlock(&root->fs_info->fs_mutex);
2558 break;
2559 case S_IFREG:
2560 btrfs_defrag_file(file);
2561 break;
2562 }
2563
2564 return 0;
2565 }
2566
2567 long btrfs_ioctl(struct file *file, unsigned int
2568 cmd, unsigned long arg)
2569 {
2570 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2571
2572 switch (cmd) {
2573 case BTRFS_IOC_SNAP_CREATE:
2574 return btrfs_ioctl_snap_create(root, (void __user *)arg);
2575 case BTRFS_IOC_DEFRAG:
2576 return btrfs_ioctl_defrag(file);
2577 case BTRFS_IOC_RESIZE:
2578 return btrfs_ioctl_resize(root, (void __user *)arg);
2579 }
2580
2581 return -ENOTTY;
2582 }
2583
2584 /*
2585 * Called inside transaction, so use GFP_NOFS
2586 */
2587 struct inode *btrfs_alloc_inode(struct super_block *sb)
2588 {
2589 struct btrfs_inode *ei;
2590
2591 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
2592 if (!ei)
2593 return NULL;
2594 ei->last_trans = 0;
2595 ei->ordered_trans = 0;
2596 return &ei->vfs_inode;
2597 }
2598
2599 void btrfs_destroy_inode(struct inode *inode)
2600 {
2601 WARN_ON(!list_empty(&inode->i_dentry));
2602 WARN_ON(inode->i_data.nrpages);
2603
2604 btrfs_drop_extent_cache(inode, 0, (u64)-1);
2605 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
2606 }
2607
2608 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
2609 static void init_once(struct kmem_cache * cachep, void *foo)
2610 #else
2611 static void init_once(void * foo, struct kmem_cache * cachep,
2612 unsigned long flags)
2613 #endif
2614 {
2615 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
2616
2617 inode_init_once(&ei->vfs_inode);
2618 }
2619
2620 void btrfs_destroy_cachep(void)
2621 {
2622 if (btrfs_inode_cachep)
2623 kmem_cache_destroy(btrfs_inode_cachep);
2624 if (btrfs_trans_handle_cachep)
2625 kmem_cache_destroy(btrfs_trans_handle_cachep);
2626 if (btrfs_transaction_cachep)
2627 kmem_cache_destroy(btrfs_transaction_cachep);
2628 if (btrfs_bit_radix_cachep)
2629 kmem_cache_destroy(btrfs_bit_radix_cachep);
2630 if (btrfs_path_cachep)
2631 kmem_cache_destroy(btrfs_path_cachep);
2632 }
2633
2634 struct kmem_cache *btrfs_cache_create(const char *name, size_t size,
2635 unsigned long extra_flags,
2636 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
2637 void (*ctor)(struct kmem_cache *, void *)
2638 #else
2639 void (*ctor)(void *, struct kmem_cache *,
2640 unsigned long)
2641 #endif
2642 )
2643 {
2644 return kmem_cache_create(name, size, 0, (SLAB_RECLAIM_ACCOUNT |
2645 SLAB_MEM_SPREAD | extra_flags), ctor
2646 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
2647 ,NULL
2648 #endif
2649 );
2650 }
2651
2652 int btrfs_init_cachep(void)
2653 {
2654 btrfs_inode_cachep = btrfs_cache_create("btrfs_inode_cache",
2655 sizeof(struct btrfs_inode),
2656 0, init_once);
2657 if (!btrfs_inode_cachep)
2658 goto fail;
2659 btrfs_trans_handle_cachep =
2660 btrfs_cache_create("btrfs_trans_handle_cache",
2661 sizeof(struct btrfs_trans_handle),
2662 0, NULL);
2663 if (!btrfs_trans_handle_cachep)
2664 goto fail;
2665 btrfs_transaction_cachep = btrfs_cache_create("btrfs_transaction_cache",
2666 sizeof(struct btrfs_transaction),
2667 0, NULL);
2668 if (!btrfs_transaction_cachep)
2669 goto fail;
2670 btrfs_path_cachep = btrfs_cache_create("btrfs_path_cache",
2671 sizeof(struct btrfs_path),
2672 0, NULL);
2673 if (!btrfs_path_cachep)
2674 goto fail;
2675 btrfs_bit_radix_cachep = btrfs_cache_create("btrfs_radix", 256,
2676 SLAB_DESTROY_BY_RCU, NULL);
2677 if (!btrfs_bit_radix_cachep)
2678 goto fail;
2679 return 0;
2680 fail:
2681 btrfs_destroy_cachep();
2682 return -ENOMEM;
2683 }
2684
2685 static int btrfs_getattr(struct vfsmount *mnt,
2686 struct dentry *dentry, struct kstat *stat)
2687 {
2688 struct inode *inode = dentry->d_inode;
2689 generic_fillattr(inode, stat);
2690 stat->blksize = PAGE_CACHE_SIZE;
2691 return 0;
2692 }
2693
2694 static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
2695 struct inode * new_dir,struct dentry *new_dentry)
2696 {
2697 struct btrfs_trans_handle *trans;
2698 struct btrfs_root *root = BTRFS_I(old_dir)->root;
2699 struct inode *new_inode = new_dentry->d_inode;
2700 struct inode *old_inode = old_dentry->d_inode;
2701 struct timespec ctime = CURRENT_TIME;
2702 struct btrfs_path *path;
2703 int ret;
2704
2705 if (S_ISDIR(old_inode->i_mode) && new_inode &&
2706 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
2707 return -ENOTEMPTY;
2708 }
2709
2710 mutex_lock(&root->fs_info->fs_mutex);
2711 ret = btrfs_check_free_space(root, 1, 0);
2712 if (ret)
2713 goto out_unlock;
2714
2715 trans = btrfs_start_transaction(root, 1);
2716
2717 btrfs_set_trans_block_group(trans, new_dir);
2718 path = btrfs_alloc_path();
2719 if (!path) {
2720 ret = -ENOMEM;
2721 goto out_fail;
2722 }
2723
2724 old_dentry->d_inode->i_nlink++;
2725 old_dir->i_ctime = old_dir->i_mtime = ctime;
2726 new_dir->i_ctime = new_dir->i_mtime = ctime;
2727 old_inode->i_ctime = ctime;
2728
2729 ret = btrfs_unlink_trans(trans, root, old_dir, old_dentry);
2730 if (ret)
2731 goto out_fail;
2732
2733 if (new_inode) {
2734 new_inode->i_ctime = CURRENT_TIME;
2735 ret = btrfs_unlink_trans(trans, root, new_dir, new_dentry);
2736 if (ret)
2737 goto out_fail;
2738 }
2739 ret = btrfs_add_link(trans, new_dentry, old_inode);
2740 if (ret)
2741 goto out_fail;
2742
2743 out_fail:
2744 btrfs_free_path(path);
2745 btrfs_end_transaction(trans, root);
2746 out_unlock:
2747 mutex_unlock(&root->fs_info->fs_mutex);
2748 return ret;
2749 }
2750
2751 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
2752 const char *symname)
2753 {
2754 struct btrfs_trans_handle *trans;
2755 struct btrfs_root *root = BTRFS_I(dir)->root;
2756 struct btrfs_path *path;
2757 struct btrfs_key key;
2758 struct inode *inode = NULL;
2759 int err;
2760 int drop_inode = 0;
2761 u64 objectid;
2762 int name_len;
2763 int datasize;
2764 unsigned long ptr;
2765 struct btrfs_file_extent_item *ei;
2766 struct extent_buffer *leaf;
2767 unsigned long nr = 0;
2768
2769 name_len = strlen(symname) + 1;
2770 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
2771 return -ENAMETOOLONG;
2772
2773 mutex_lock(&root->fs_info->fs_mutex);
2774 err = btrfs_check_free_space(root, 1, 0);
2775 if (err)
2776 goto out_fail;
2777
2778 trans = btrfs_start_transaction(root, 1);
2779 btrfs_set_trans_block_group(trans, dir);
2780
2781 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2782 if (err) {
2783 err = -ENOSPC;
2784 goto out_unlock;
2785 }
2786
2787 inode = btrfs_new_inode(trans, root, objectid,
2788 BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO);
2789 err = PTR_ERR(inode);
2790 if (IS_ERR(inode))
2791 goto out_unlock;
2792
2793 btrfs_set_trans_block_group(trans, inode);
2794 err = btrfs_add_nondir(trans, dentry, inode);
2795 if (err)
2796 drop_inode = 1;
2797 else {
2798 inode->i_mapping->a_ops = &btrfs_aops;
2799 inode->i_fop = &btrfs_file_operations;
2800 inode->i_op = &btrfs_file_inode_operations;
2801 extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
2802 inode->i_mapping, GFP_NOFS);
2803 BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
2804 }
2805 dir->i_sb->s_dirt = 1;
2806 btrfs_update_inode_block_group(trans, inode);
2807 btrfs_update_inode_block_group(trans, dir);
2808 if (drop_inode)
2809 goto out_unlock;
2810
2811 path = btrfs_alloc_path();
2812 BUG_ON(!path);
2813 key.objectid = inode->i_ino;
2814 key.offset = 0;
2815 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
2816 datasize = btrfs_file_extent_calc_inline_size(name_len);
2817 err = btrfs_insert_empty_item(trans, root, path, &key,
2818 datasize);
2819 if (err) {
2820 drop_inode = 1;
2821 goto out_unlock;
2822 }
2823 leaf = path->nodes[0];
2824 ei = btrfs_item_ptr(leaf, path->slots[0],
2825 struct btrfs_file_extent_item);
2826 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
2827 btrfs_set_file_extent_type(leaf, ei,
2828 BTRFS_FILE_EXTENT_INLINE);
2829 ptr = btrfs_file_extent_inline_start(ei);
2830 write_extent_buffer(leaf, symname, ptr, name_len);
2831 btrfs_mark_buffer_dirty(leaf);
2832 btrfs_free_path(path);
2833
2834 inode->i_op = &btrfs_symlink_inode_operations;
2835 inode->i_mapping->a_ops = &btrfs_symlink_aops;
2836 inode->i_size = name_len - 1;
2837 err = btrfs_update_inode(trans, root, inode);
2838 if (err)
2839 drop_inode = 1;
2840
2841 out_unlock:
2842 nr = trans->blocks_used;
2843 btrfs_end_transaction(trans, root);
2844 out_fail:
2845 mutex_unlock(&root->fs_info->fs_mutex);
2846 if (drop_inode) {
2847 inode_dec_link_count(inode);
2848 iput(inode);
2849 }
2850 btrfs_btree_balance_dirty(root, nr);
2851 btrfs_throttle(root);
2852 return err;
2853 }
2854 static int btrfs_permission(struct inode *inode, int mask,
2855 struct nameidata *nd)
2856 {
2857 if (btrfs_test_flag(inode, READONLY) && (mask & MAY_WRITE))
2858 return -EACCES;
2859 return generic_permission(inode, mask, NULL);
2860 }
2861
2862 static struct inode_operations btrfs_dir_inode_operations = {
2863 .lookup = btrfs_lookup,
2864 .create = btrfs_create,
2865 .unlink = btrfs_unlink,
2866 .link = btrfs_link,
2867 .mkdir = btrfs_mkdir,
2868 .rmdir = btrfs_rmdir,
2869 .rename = btrfs_rename,
2870 .symlink = btrfs_symlink,
2871 .setattr = btrfs_setattr,
2872 .mknod = btrfs_mknod,
2873 .setxattr = generic_setxattr,
2874 .getxattr = generic_getxattr,
2875 .listxattr = btrfs_listxattr,
2876 .removexattr = generic_removexattr,
2877 .permission = btrfs_permission,
2878 };
2879 static struct inode_operations btrfs_dir_ro_inode_operations = {
2880 .lookup = btrfs_lookup,
2881 .permission = btrfs_permission,
2882 };
2883 static struct file_operations btrfs_dir_file_operations = {
2884 .llseek = generic_file_llseek,
2885 .read = generic_read_dir,
2886 .readdir = btrfs_readdir,
2887 .unlocked_ioctl = btrfs_ioctl,
2888 #ifdef CONFIG_COMPAT
2889 .compat_ioctl = btrfs_ioctl,
2890 #endif
2891 };
2892
2893 static struct extent_map_ops btrfs_extent_map_ops = {
2894 .fill_delalloc = run_delalloc_range,
2895 .writepage_io_hook = btrfs_writepage_io_hook,
2896 .readpage_io_hook = btrfs_readpage_io_hook,
2897 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
2898 };
2899
2900 static struct address_space_operations btrfs_aops = {
2901 .readpage = btrfs_readpage,
2902 .writepage = btrfs_writepage,
2903 .writepages = btrfs_writepages,
2904 .readpages = btrfs_readpages,
2905 .sync_page = block_sync_page,
2906 .bmap = btrfs_bmap,
2907 .invalidatepage = btrfs_invalidatepage,
2908 .releasepage = btrfs_releasepage,
2909 .set_page_dirty = __set_page_dirty_nobuffers,
2910 };
2911
2912 static struct address_space_operations btrfs_symlink_aops = {
2913 .readpage = btrfs_readpage,
2914 .writepage = btrfs_writepage,
2915 .invalidatepage = btrfs_invalidatepage,
2916 .releasepage = btrfs_releasepage,
2917 };
2918
2919 static struct inode_operations btrfs_file_inode_operations = {
2920 .truncate = btrfs_truncate,
2921 .getattr = btrfs_getattr,
2922 .setattr = btrfs_setattr,
2923 .setxattr = generic_setxattr,
2924 .getxattr = generic_getxattr,
2925 .listxattr = btrfs_listxattr,
2926 .removexattr = generic_removexattr,
2927 .permission = btrfs_permission,
2928 };
2929 static struct inode_operations btrfs_special_inode_operations = {
2930 .getattr = btrfs_getattr,
2931 .setattr = btrfs_setattr,
2932 .permission = btrfs_permission,
2933 };
2934 static struct inode_operations btrfs_symlink_inode_operations = {
2935 .readlink = generic_readlink,
2936 .follow_link = page_follow_link_light,
2937 .put_link = page_put_link,
2938 .permission = btrfs_permission,
2939 };
Linux kernel - Deliverables
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