projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Btrfs: Run igrab on data=ordered inodes to prevent deadlocks during writeout
[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 return 0;
84
85 if (for_del)
86 thresh = total * 90;
87 else
88 thresh = total * 85;
89
90 do_div(thresh, 100);
91
92 spin_lock(&root->fs_info->delalloc_lock);
93 if (used + root->fs_info->delalloc_bytes + num_required > thresh)
94 ret = -ENOSPC;
95 spin_unlock(&root->fs_info->delalloc_lock);
96 return ret;
97 }
98
99 static int cow_file_range(struct inode *inode, u64 start, u64 end)
100 {
101 struct btrfs_root *root = BTRFS_I(inode)->root;
102 struct btrfs_trans_handle *trans;
103 u64 alloc_hint = 0;
104 u64 num_bytes;
105 u64 cur_alloc_size;
106 u64 blocksize = root->sectorsize;
107 struct btrfs_key ins;
108 int ret;
109
110 trans = btrfs_start_transaction(root, 1);
111 BUG_ON(!trans);
112 btrfs_set_trans_block_group(trans, inode);
113
114 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
115 num_bytes = max(blocksize, num_bytes);
116 ret = btrfs_drop_extents(trans, root, inode,
117 start, start + num_bytes, start, &alloc_hint);
118
119 if (alloc_hint == EXTENT_MAP_INLINE)
120 goto out;
121
122 while(num_bytes > 0) {
123 cur_alloc_size = min(num_bytes, root->fs_info->max_extent);
124 ret = btrfs_alloc_extent(trans, root, cur_alloc_size,
125 root->root_key.objectid,
126 trans->transid,
127 inode->i_ino, start, 0,
128 alloc_hint, (u64)-1, &ins, 1);
129 if (ret) {
130 WARN_ON(1);
131 goto out;
132 }
133 ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
134 start, ins.objectid, ins.offset,
135 ins.offset);
136 num_bytes -= cur_alloc_size;
137 alloc_hint = ins.objectid + ins.offset;
138 start += cur_alloc_size;
139 }
140 btrfs_add_ordered_inode(inode);
141 out:
142 btrfs_end_transaction(trans, root);
143 return ret;
144 }
145
146 static int run_delalloc_nocow(struct inode *inode, u64 start, u64 end)
147 {
148 u64 extent_start;
149 u64 extent_end;
150 u64 bytenr;
151 u64 cow_end;
152 u64 loops = 0;
153 u64 total_fs_bytes;
154 struct btrfs_root *root = BTRFS_I(inode)->root;
155 struct extent_buffer *leaf;
156 int found_type;
157 struct btrfs_path *path;
158 struct btrfs_file_extent_item *item;
159 int ret;
160 int err;
161 struct btrfs_key found_key;
162
163 total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
164 path = btrfs_alloc_path();
165 BUG_ON(!path);
166 again:
167 ret = btrfs_lookup_file_extent(NULL, root, path,
168 inode->i_ino, start, 0);
169 if (ret < 0) {
170 btrfs_free_path(path);
171 return ret;
172 }
173
174 cow_end = end;
175 if (ret != 0) {
176 if (path->slots[0] == 0)
177 goto not_found;
178 path->slots[0]--;
179 }
180
181 leaf = path->nodes[0];
182 item = btrfs_item_ptr(leaf, path->slots[0],
183 struct btrfs_file_extent_item);
184
185 /* are we inside the extent that was found? */
186 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
187 found_type = btrfs_key_type(&found_key);
188 if (found_key.objectid != inode->i_ino ||
189 found_type != BTRFS_EXTENT_DATA_KEY) {
190 goto not_found;
191 }
192
193 found_type = btrfs_file_extent_type(leaf, item);
194 extent_start = found_key.offset;
195 if (found_type == BTRFS_FILE_EXTENT_REG) {
196 u64 extent_num_bytes;
197
198 extent_num_bytes = btrfs_file_extent_num_bytes(leaf, item);
199 extent_end = extent_start + extent_num_bytes;
200 err = 0;
201
202 if (loops && start != extent_start)
203 goto not_found;
204
205 if (start < extent_start || start >= extent_end)
206 goto not_found;
207
208 cow_end = min(end, extent_end - 1);
209 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
210 if (bytenr == 0)
211 goto not_found;
212
213 /*
214 * we may be called by the resizer, make sure we're inside
215 * the limits of the FS
216 */
217 if (bytenr + extent_num_bytes > total_fs_bytes)
218 goto not_found;
219
220 if (btrfs_count_snapshots_in_path(root, path, bytenr) != 1) {
221 goto not_found;
222 }
223
224 start = extent_end;
225 } else {
226 goto not_found;
227 }
228 loop:
229 if (start > end) {
230 btrfs_free_path(path);
231 return 0;
232 }
233 btrfs_release_path(root, path);
234 loops++;
235 goto again;
236
237 not_found:
238 cow_file_range(inode, start, cow_end);
239 start = cow_end + 1;
240 goto loop;
241 }
242
243 static int run_delalloc_range(struct inode *inode, u64 start, u64 end)
244 {
245 struct btrfs_root *root = BTRFS_I(inode)->root;
246 u64 num_bytes;
247 int ret;
248 mutex_lock(&root->fs_info->fs_mutex);
249 if (btrfs_test_opt(root, NODATACOW) ||
250 btrfs_test_flag(inode, NODATACOW))
251 ret = run_delalloc_nocow(inode, start, end);
252 else
253 ret = cow_file_range(inode, start, end);
254
255 spin_lock(&root->fs_info->delalloc_lock);
256 num_bytes = end + 1 - start;
257 if (root->fs_info->delalloc_bytes < num_bytes) {
258 printk("delalloc accounting error total %llu sub %llu\n",
259 root->fs_info->delalloc_bytes, num_bytes);
260 } else {
261 root->fs_info->delalloc_bytes -= num_bytes;
262 }
263 spin_unlock(&root->fs_info->delalloc_lock);
264
265 mutex_unlock(&root->fs_info->fs_mutex);
266 return ret;
267 }
268
269 int btrfs_writepage_io_hook(struct page *page, u64 start, u64 end)
270 {
271 struct inode *inode = page->mapping->host;
272 struct btrfs_root *root = BTRFS_I(inode)->root;
273 struct btrfs_trans_handle *trans;
274 char *kaddr;
275 int ret = 0;
276 u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
277 size_t offset = start - page_start;
278 if (btrfs_test_opt(root, NODATASUM) ||
279 btrfs_test_flag(inode, NODATASUM))
280 return 0;
281 mutex_lock(&root->fs_info->fs_mutex);
282 trans = btrfs_start_transaction(root, 1);
283 btrfs_set_trans_block_group(trans, inode);
284 kaddr = kmap(page);
285 btrfs_csum_file_block(trans, root, inode, inode->i_ino,
286 start, kaddr + offset, end - start + 1);
287 kunmap(page);
288 ret = btrfs_end_transaction(trans, root);
289 BUG_ON(ret);
290 mutex_unlock(&root->fs_info->fs_mutex);
291 return ret;
292 }
293
294 int btrfs_readpage_io_hook(struct page *page, u64 start, u64 end)
295 {
296 int ret = 0;
297 struct inode *inode = page->mapping->host;
298 struct btrfs_root *root = BTRFS_I(inode)->root;
299 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
300 struct btrfs_csum_item *item;
301 struct btrfs_path *path = NULL;
302 u32 csum;
303 if (btrfs_test_opt(root, NODATASUM) ||
304 btrfs_test_flag(inode, NODATASUM))
305 return 0;
306 mutex_lock(&root->fs_info->fs_mutex);
307 path = btrfs_alloc_path();
308 item = btrfs_lookup_csum(NULL, root, path, inode->i_ino, start, 0);
309 if (IS_ERR(item)) {
310 ret = PTR_ERR(item);
311 /* a csum that isn't present is a preallocated region. */
312 if (ret == -ENOENT || ret == -EFBIG)
313 ret = 0;
314 csum = 0;
315 goto out;
316 }
317 read_extent_buffer(path->nodes[0], &csum, (unsigned long)item,
318 BTRFS_CRC32_SIZE);
319 set_state_private(em_tree, start, csum);
320 out:
321 if (path)
322 btrfs_free_path(path);
323 mutex_unlock(&root->fs_info->fs_mutex);
324 return ret;
325 }
326
327 int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end)
328 {
329 size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
330 struct inode *inode = page->mapping->host;
331 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
332 char *kaddr;
333 u64 private;
334 int ret;
335 struct btrfs_root *root = BTRFS_I(inode)->root;
336 u32 csum = ~(u32)0;
337 unsigned long flags;
338 if (btrfs_test_opt(root, NODATASUM) ||
339 btrfs_test_flag(inode, NODATASUM))
340 return 0;
341 ret = get_state_private(em_tree, start, &private);
342 local_irq_save(flags);
343 kaddr = kmap_atomic(page, KM_IRQ0);
344 if (ret) {
345 goto zeroit;
346 }
347 csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1);
348 btrfs_csum_final(csum, (char *)&csum);
349 if (csum != private) {
350 goto zeroit;
351 }
352 kunmap_atomic(kaddr, KM_IRQ0);
353 local_irq_restore(flags);
354 return 0;
355
356 zeroit:
357 printk("btrfs csum failed ino %lu off %llu\n",
358 page->mapping->host->i_ino, (unsigned long long)start);
359 memset(kaddr + offset, 1, end - start + 1);
360 flush_dcache_page(page);
361 kunmap_atomic(kaddr, KM_IRQ0);
362 local_irq_restore(flags);
363 return 0;
364 }
365
366 void btrfs_read_locked_inode(struct inode *inode)
367 {
368 struct btrfs_path *path;
369 struct extent_buffer *leaf;
370 struct btrfs_inode_item *inode_item;
371 struct btrfs_inode_timespec *tspec;
372 struct btrfs_root *root = BTRFS_I(inode)->root;
373 struct btrfs_key location;
374 u64 alloc_group_block;
375 u32 rdev;
376 int ret;
377
378 path = btrfs_alloc_path();
379 BUG_ON(!path);
380 mutex_lock(&root->fs_info->fs_mutex);
381 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
382
383 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
384 if (ret)
385 goto make_bad;
386
387 leaf = path->nodes[0];
388 inode_item = btrfs_item_ptr(leaf, path->slots[0],
389 struct btrfs_inode_item);
390
391 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
392 inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
393 inode->i_uid = btrfs_inode_uid(leaf, inode_item);
394 inode->i_gid = btrfs_inode_gid(leaf, inode_item);
395 inode->i_size = btrfs_inode_size(leaf, inode_item);
396
397 tspec = btrfs_inode_atime(inode_item);
398 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
399 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
400
401 tspec = btrfs_inode_mtime(inode_item);
402 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
403 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
404
405 tspec = btrfs_inode_ctime(inode_item);
406 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
407 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
408
409 inode->i_blocks = btrfs_inode_nblocks(leaf, inode_item);
410 inode->i_generation = btrfs_inode_generation(leaf, inode_item);
411 inode->i_rdev = 0;
412 rdev = btrfs_inode_rdev(leaf, inode_item);
413
414 alloc_group_block = btrfs_inode_block_group(leaf, inode_item);
415 BTRFS_I(inode)->block_group = btrfs_lookup_block_group(root->fs_info,
416 alloc_group_block);
417 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
418 if (!BTRFS_I(inode)->block_group) {
419 BTRFS_I(inode)->block_group = btrfs_find_block_group(root,
420 NULL, 0, 0, 0);
421 }
422 btrfs_free_path(path);
423 inode_item = NULL;
424
425 mutex_unlock(&root->fs_info->fs_mutex);
426
427 switch (inode->i_mode & S_IFMT) {
428 case S_IFREG:
429 inode->i_mapping->a_ops = &btrfs_aops;
430 BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
431 inode->i_fop = &btrfs_file_operations;
432 inode->i_op = &btrfs_file_inode_operations;
433 break;
434 case S_IFDIR:
435 inode->i_fop = &btrfs_dir_file_operations;
436 if (root == root->fs_info->tree_root)
437 inode->i_op = &btrfs_dir_ro_inode_operations;
438 else
439 inode->i_op = &btrfs_dir_inode_operations;
440 break;
441 case S_IFLNK:
442 inode->i_op = &btrfs_symlink_inode_operations;
443 inode->i_mapping->a_ops = &btrfs_symlink_aops;
444 break;
445 default:
446 init_special_inode(inode, inode->i_mode, rdev);
447 break;
448 }
449 return;
450
451 make_bad:
452 btrfs_release_path(root, path);
453 btrfs_free_path(path);
454 mutex_unlock(&root->fs_info->fs_mutex);
455 make_bad_inode(inode);
456 }
457
458 static void fill_inode_item(struct extent_buffer *leaf,
459 struct btrfs_inode_item *item,
460 struct inode *inode)
461 {
462 btrfs_set_inode_uid(leaf, item, inode->i_uid);
463 btrfs_set_inode_gid(leaf, item, inode->i_gid);
464 btrfs_set_inode_size(leaf, item, inode->i_size);
465 btrfs_set_inode_mode(leaf, item, inode->i_mode);
466 btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
467
468 btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
469 inode->i_atime.tv_sec);
470 btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
471 inode->i_atime.tv_nsec);
472
473 btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
474 inode->i_mtime.tv_sec);
475 btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
476 inode->i_mtime.tv_nsec);
477
478 btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
479 inode->i_ctime.tv_sec);
480 btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
481 inode->i_ctime.tv_nsec);
482
483 btrfs_set_inode_nblocks(leaf, item, inode->i_blocks);
484 btrfs_set_inode_generation(leaf, item, inode->i_generation);
485 btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
486 btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
487 btrfs_set_inode_block_group(leaf, item,
488 BTRFS_I(inode)->block_group->key.objectid);
489 }
490
491 int btrfs_update_inode(struct btrfs_trans_handle *trans,
492 struct btrfs_root *root,
493 struct inode *inode)
494 {
495 struct btrfs_inode_item *inode_item;
496 struct btrfs_path *path;
497 struct extent_buffer *leaf;
498 int ret;
499
500 path = btrfs_alloc_path();
501 BUG_ON(!path);
502 ret = btrfs_lookup_inode(trans, root, path,
503 &BTRFS_I(inode)->location, 1);
504 if (ret) {
505 if (ret > 0)
506 ret = -ENOENT;
507 goto failed;
508 }
509
510 leaf = path->nodes[0];
511 inode_item = btrfs_item_ptr(leaf, path->slots[0],
512 struct btrfs_inode_item);
513
514 fill_inode_item(leaf, inode_item, inode);
515 btrfs_mark_buffer_dirty(leaf);
516 btrfs_set_inode_last_trans(trans, inode);
517 ret = 0;
518 failed:
519 btrfs_release_path(root, path);
520 btrfs_free_path(path);
521 return ret;
522 }
523
524
525 static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
526 struct btrfs_root *root,
527 struct inode *dir,
528 struct dentry *dentry)
529 {
530 struct btrfs_path *path;
531 const char *name = dentry->d_name.name;
532 int name_len = dentry->d_name.len;
533 int ret = 0;
534 struct extent_buffer *leaf;
535 struct btrfs_dir_item *di;
536 struct btrfs_key key;
537
538 path = btrfs_alloc_path();
539 if (!path) {
540 ret = -ENOMEM;
541 goto err;
542 }
543
544 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
545 name, name_len, -1);
546 if (IS_ERR(di)) {
547 ret = PTR_ERR(di);
548 goto err;
549 }
550 if (!di) {
551 ret = -ENOENT;
552 goto err;
553 }
554 leaf = path->nodes[0];
555 btrfs_dir_item_key_to_cpu(leaf, di, &key);
556 ret = btrfs_delete_one_dir_name(trans, root, path, di);
557 if (ret)
558 goto err;
559 btrfs_release_path(root, path);
560
561 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
562 key.objectid, name, name_len, -1);
563 if (IS_ERR(di)) {
564 ret = PTR_ERR(di);
565 goto err;
566 }
567 if (!di) {
568 ret = -ENOENT;
569 goto err;
570 }
571 ret = btrfs_delete_one_dir_name(trans, root, path, di);
572
573 dentry->d_inode->i_ctime = dir->i_ctime;
574 ret = btrfs_del_inode_ref(trans, root, name, name_len,
575 dentry->d_inode->i_ino,
576 dentry->d_parent->d_inode->i_ino);
577 if (ret) {
578 printk("failed to delete reference to %.*s, "
579 "inode %lu parent %lu\n", name_len, name,
580 dentry->d_inode->i_ino,
581 dentry->d_parent->d_inode->i_ino);
582 }
583 err:
584 btrfs_free_path(path);
585 if (!ret) {
586 dir->i_size -= name_len * 2;
587 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
588 btrfs_update_inode(trans, root, dir);
589 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
590 dentry->d_inode->i_nlink--;
591 #else
592 drop_nlink(dentry->d_inode);
593 #endif
594 ret = btrfs_update_inode(trans, root, dentry->d_inode);
595 dir->i_sb->s_dirt = 1;
596 }
597 return ret;
598 }
599
600 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
601 {
602 struct btrfs_root *root;
603 struct btrfs_trans_handle *trans;
604 struct inode *inode = dentry->d_inode;
605 int ret;
606 unsigned long nr = 0;
607
608 root = BTRFS_I(dir)->root;
609 mutex_lock(&root->fs_info->fs_mutex);
610
611 ret = btrfs_check_free_space(root, 1, 1);
612 if (ret)
613 goto fail;
614
615 trans = btrfs_start_transaction(root, 1);
616
617 btrfs_set_trans_block_group(trans, dir);
618 ret = btrfs_unlink_trans(trans, root, dir, dentry);
619 nr = trans->blocks_used;
620
621 if (inode->i_nlink == 0) {
622 int found;
623 /* if the inode isn't linked anywhere,
624 * we don't need to worry about
625 * data=ordered
626 */
627 found = btrfs_del_ordered_inode(inode);
628 if (found == 1) {
629 atomic_dec(&inode->i_count);
630 }
631 }
632
633 btrfs_end_transaction(trans, root);
634 fail:
635 mutex_unlock(&root->fs_info->fs_mutex);
636 btrfs_btree_balance_dirty(root, nr);
637 btrfs_throttle(root);
638 return ret;
639 }
640
641 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
642 {
643 struct inode *inode = dentry->d_inode;
644 int err = 0;
645 int ret;
646 struct btrfs_root *root = BTRFS_I(dir)->root;
647 struct btrfs_trans_handle *trans;
648 unsigned long nr = 0;
649
650 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
651 return -ENOTEMPTY;
652
653 mutex_lock(&root->fs_info->fs_mutex);
654 ret = btrfs_check_free_space(root, 1, 1);
655 if (ret)
656 goto fail;
657
658 trans = btrfs_start_transaction(root, 1);
659 btrfs_set_trans_block_group(trans, dir);
660
661 /* now the directory is empty */
662 err = btrfs_unlink_trans(trans, root, dir, dentry);
663 if (!err) {
664 inode->i_size = 0;
665 }
666
667 nr = trans->blocks_used;
668 ret = btrfs_end_transaction(trans, root);
669 fail:
670 mutex_unlock(&root->fs_info->fs_mutex);
671 btrfs_btree_balance_dirty(root, nr);
672 btrfs_throttle(root);
673
674 if (ret && !err)
675 err = ret;
676 return err;
677 }
678
679 static int btrfs_free_inode(struct btrfs_trans_handle *trans,
680 struct btrfs_root *root,
681 struct inode *inode)
682 {
683 struct btrfs_path *path;
684 int ret;
685
686 clear_inode(inode);
687
688 path = btrfs_alloc_path();
689 BUG_ON(!path);
690 ret = btrfs_lookup_inode(trans, root, path,
691 &BTRFS_I(inode)->location, -1);
692 if (ret > 0)
693 ret = -ENOENT;
694 if (!ret)
695 ret = btrfs_del_item(trans, root, path);
696 btrfs_free_path(path);
697 return ret;
698 }
699
700 /*
701 * this can truncate away extent items, csum items and directory items.
702 * It starts at a high offset and removes keys until it can't find
703 * any higher than i_size.
704 *
705 * csum items that cross the new i_size are truncated to the new size
706 * as well.
707 */
708 static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
709 struct btrfs_root *root,
710 struct inode *inode)
711 {
712 int ret;
713 struct btrfs_path *path;
714 struct btrfs_key key;
715 struct btrfs_key found_key;
716 u32 found_type;
717 struct extent_buffer *leaf;
718 struct btrfs_file_extent_item *fi;
719 u64 extent_start = 0;
720 u64 extent_num_bytes = 0;
721 u64 item_end = 0;
722 u64 root_gen = 0;
723 u64 root_owner = 0;
724 int found_extent;
725 int del_item;
726 int extent_type = -1;
727
728 btrfs_drop_extent_cache(inode, inode->i_size, (u64)-1);
729 path = btrfs_alloc_path();
730 path->reada = -1;
731 BUG_ON(!path);
732
733 /* FIXME, add redo link to tree so we don't leak on crash */
734 key.objectid = inode->i_ino;
735 key.offset = (u64)-1;
736 key.type = (u8)-1;
737
738 while(1) {
739 btrfs_init_path(path);
740 fi = NULL;
741 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
742 if (ret < 0) {
743 goto error;
744 }
745 if (ret > 0) {
746 BUG_ON(path->slots[0] == 0);
747 path->slots[0]--;
748 }
749 leaf = path->nodes[0];
750 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
751 found_type = btrfs_key_type(&found_key);
752
753 if (found_key.objectid != inode->i_ino)
754 break;
755
756 if (found_type != BTRFS_CSUM_ITEM_KEY &&
757 found_type != BTRFS_DIR_ITEM_KEY &&
758 found_type != BTRFS_DIR_INDEX_KEY &&
759 found_type != BTRFS_EXTENT_DATA_KEY)
760 break;
761
762 item_end = found_key.offset;
763 if (found_type == BTRFS_EXTENT_DATA_KEY) {
764 fi = btrfs_item_ptr(leaf, path->slots[0],
765 struct btrfs_file_extent_item);
766 extent_type = btrfs_file_extent_type(leaf, fi);
767 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
768 item_end +=
769 btrfs_file_extent_num_bytes(leaf, fi);
770 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
771 struct btrfs_item *item = btrfs_item_nr(leaf,
772 path->slots[0]);
773 item_end += btrfs_file_extent_inline_len(leaf,
774 item);
775 }
776 item_end--;
777 }
778 if (found_type == BTRFS_CSUM_ITEM_KEY) {
779 ret = btrfs_csum_truncate(trans, root, path,
780 inode->i_size);
781 BUG_ON(ret);
782 }
783 if (item_end < inode->i_size) {
784 if (found_type == BTRFS_DIR_ITEM_KEY) {
785 found_type = BTRFS_INODE_ITEM_KEY;
786 } else if (found_type == BTRFS_EXTENT_ITEM_KEY) {
787 found_type = BTRFS_CSUM_ITEM_KEY;
788 } else if (found_type) {
789 found_type--;
790 } else {
791 break;
792 }
793 btrfs_set_key_type(&key, found_type);
794 btrfs_release_path(root, path);
795 continue;
796 }
797 if (found_key.offset >= inode->i_size)
798 del_item = 1;
799 else
800 del_item = 0;
801 found_extent = 0;
802
803 /* FIXME, shrink the extent if the ref count is only 1 */
804 if (found_type != BTRFS_EXTENT_DATA_KEY)
805 goto delete;
806
807 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
808 u64 num_dec;
809 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
810 if (!del_item) {
811 u64 orig_num_bytes =
812 btrfs_file_extent_num_bytes(leaf, fi);
813 extent_num_bytes = inode->i_size -
814 found_key.offset + root->sectorsize - 1;
815 btrfs_set_file_extent_num_bytes(leaf, fi,
816 extent_num_bytes);
817 num_dec = (orig_num_bytes -
818 extent_num_bytes) >> 9;
819 if (extent_start != 0) {
820 inode->i_blocks -= num_dec;
821 }
822 btrfs_mark_buffer_dirty(leaf);
823 } else {
824 extent_num_bytes =
825 btrfs_file_extent_disk_num_bytes(leaf,
826 fi);
827 /* FIXME blocksize != 4096 */
828 num_dec = btrfs_file_extent_num_bytes(leaf,
829 fi) >> 9;
830 if (extent_start != 0) {
831 found_extent = 1;
832 inode->i_blocks -= num_dec;
833 }
834 root_gen = btrfs_header_generation(leaf);
835 root_owner = btrfs_header_owner(leaf);
836 }
837 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE &&
838 !del_item) {
839 u32 newsize = inode->i_size - found_key.offset;
840 newsize = btrfs_file_extent_calc_inline_size(newsize);
841 ret = btrfs_truncate_item(trans, root, path,
842 newsize, 1);
843 BUG_ON(ret);
844 }
845 delete:
846 if (del_item) {
847 ret = btrfs_del_item(trans, root, path);
848 if (ret)
849 goto error;
850 } else {
851 break;
852 }
853 btrfs_release_path(root, path);
854 if (found_extent) {
855 ret = btrfs_free_extent(trans, root, extent_start,
856 extent_num_bytes,
857 root_owner,
858 root_gen, inode->i_ino,
859 found_key.offset, 0);
860 BUG_ON(ret);
861 }
862 }
863 ret = 0;
864 error:
865 btrfs_release_path(root, path);
866 btrfs_free_path(path);
867 inode->i_sb->s_dirt = 1;
868 return ret;
869 }
870
871 static int btrfs_cow_one_page(struct inode *inode, struct page *page,
872 size_t zero_start)
873 {
874 char *kaddr;
875 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
876 struct btrfs_root *root = BTRFS_I(inode)->root;
877 u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
878 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
879 u64 existing_delalloc;
880 u64 delalloc_start;
881 int ret = 0;
882
883 WARN_ON(!PageLocked(page));
884 set_page_extent_mapped(page);
885
886 lock_extent(em_tree, page_start, page_end, GFP_NOFS);
887 delalloc_start = page_start;
888 existing_delalloc = count_range_bits(&BTRFS_I(inode)->extent_tree,
889 &delalloc_start, page_end,
890 PAGE_CACHE_SIZE, EXTENT_DELALLOC);
891 set_extent_delalloc(&BTRFS_I(inode)->extent_tree, page_start,
892 page_end, GFP_NOFS);
893
894 spin_lock(&root->fs_info->delalloc_lock);
895 root->fs_info->delalloc_bytes += PAGE_CACHE_SIZE - existing_delalloc;
896 spin_unlock(&root->fs_info->delalloc_lock);
897
898 if (zero_start != PAGE_CACHE_SIZE) {
899 kaddr = kmap(page);
900 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
901 flush_dcache_page(page);
902 kunmap(page);
903 }
904 set_page_dirty(page);
905 unlock_extent(em_tree, page_start, page_end, GFP_NOFS);
906
907 return ret;
908 }
909
910 /*
911 * taken from block_truncate_page, but does cow as it zeros out
912 * any bytes left in the last page in the file.
913 */
914 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
915 {
916 struct inode *inode = mapping->host;
917 struct btrfs_root *root = BTRFS_I(inode)->root;
918 u32 blocksize = root->sectorsize;
919 pgoff_t index = from >> PAGE_CACHE_SHIFT;
920 unsigned offset = from & (PAGE_CACHE_SIZE-1);
921 struct page *page;
922 int ret = 0;
923 u64 page_start;
924
925 if ((offset & (blocksize - 1)) == 0)
926 goto out;
927
928 ret = -ENOMEM;
929 page = grab_cache_page(mapping, index);
930 if (!page)
931 goto out;
932 if (!PageUptodate(page)) {
933 ret = btrfs_readpage(NULL, page);
934 lock_page(page);
935 if (!PageUptodate(page)) {
936 ret = -EIO;
937 goto out;
938 }
939 }
940 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
941
942 ret = btrfs_cow_one_page(inode, page, offset);
943
944 unlock_page(page);
945 page_cache_release(page);
946 out:
947 return ret;
948 }
949
950 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
951 {
952 struct inode *inode = dentry->d_inode;
953 int err;
954
955 err = inode_change_ok(inode, attr);
956 if (err)
957 return err;
958
959 if (S_ISREG(inode->i_mode) &&
960 attr->ia_valid & ATTR_SIZE && attr->ia_size > inode->i_size) {
961 struct btrfs_trans_handle *trans;
962 struct btrfs_root *root = BTRFS_I(inode)->root;
963 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
964
965 u64 mask = root->sectorsize - 1;
966 u64 pos = (inode->i_size + mask) & ~mask;
967 u64 block_end = attr->ia_size | mask;
968 u64 hole_size;
969 u64 alloc_hint = 0;
970
971 if (attr->ia_size <= pos)
972 goto out;
973
974 mutex_lock(&root->fs_info->fs_mutex);
975 err = btrfs_check_free_space(root, 1, 0);
976 mutex_unlock(&root->fs_info->fs_mutex);
977 if (err)
978 goto fail;
979
980 btrfs_truncate_page(inode->i_mapping, inode->i_size);
981
982 lock_extent(em_tree, pos, block_end, GFP_NOFS);
983 hole_size = (attr->ia_size - pos + mask) & ~mask;
984
985 mutex_lock(&root->fs_info->fs_mutex);
986 trans = btrfs_start_transaction(root, 1);
987 btrfs_set_trans_block_group(trans, inode);
988 err = btrfs_drop_extents(trans, root, inode,
989 pos, pos + hole_size, pos,
990 &alloc_hint);
991
992 if (alloc_hint != EXTENT_MAP_INLINE) {
993 err = btrfs_insert_file_extent(trans, root,
994 inode->i_ino,
995 pos, 0, 0, hole_size);
996 }
997 btrfs_end_transaction(trans, root);
998 mutex_unlock(&root->fs_info->fs_mutex);
999 unlock_extent(em_tree, pos, block_end, GFP_NOFS);
1000 if (err)
1001 return err;
1002 }
1003 out:
1004 err = inode_setattr(inode, attr);
1005 fail:
1006 return err;
1007 }
1008
1009 void btrfs_put_inode(struct inode *inode)
1010 {
1011 int ret;
1012
1013 if (!BTRFS_I(inode)->ordered_trans) {
1014 return;
1015 }
1016
1017 if (mapping_tagged(inode->i_mapping, PAGECACHE_TAG_DIRTY) ||
1018 mapping_tagged(inode->i_mapping, PAGECACHE_TAG_WRITEBACK))
1019 return;
1020
1021 ret = btrfs_del_ordered_inode(inode);
1022 if (ret == 1) {
1023 atomic_dec(&inode->i_count);
1024 }
1025 }
1026
1027 void btrfs_delete_inode(struct inode *inode)
1028 {
1029 struct btrfs_trans_handle *trans;
1030 struct btrfs_root *root = BTRFS_I(inode)->root;
1031 unsigned long nr;
1032 int ret;
1033
1034 truncate_inode_pages(&inode->i_data, 0);
1035 if (is_bad_inode(inode)) {
1036 goto no_delete;
1037 }
1038
1039 inode->i_size = 0;
1040 mutex_lock(&root->fs_info->fs_mutex);
1041 trans = btrfs_start_transaction(root, 1);
1042
1043 btrfs_set_trans_block_group(trans, inode);
1044 ret = btrfs_truncate_in_trans(trans, root, inode);
1045 if (ret)
1046 goto no_delete_lock;
1047 ret = btrfs_delete_xattrs(trans, root, inode);
1048 if (ret)
1049 goto no_delete_lock;
1050 ret = btrfs_free_inode(trans, root, inode);
1051 if (ret)
1052 goto no_delete_lock;
1053 nr = trans->blocks_used;
1054
1055 btrfs_end_transaction(trans, root);
1056 mutex_unlock(&root->fs_info->fs_mutex);
1057 btrfs_btree_balance_dirty(root, nr);
1058 btrfs_throttle(root);
1059 return;
1060
1061 no_delete_lock:
1062 nr = trans->blocks_used;
1063 btrfs_end_transaction(trans, root);
1064 mutex_unlock(&root->fs_info->fs_mutex);
1065 btrfs_btree_balance_dirty(root, nr);
1066 btrfs_throttle(root);
1067 no_delete:
1068 clear_inode(inode);
1069 }
1070
1071 /*
1072 * this returns the key found in the dir entry in the location pointer.
1073 * If no dir entries were found, location->objectid is 0.
1074 */
1075 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
1076 struct btrfs_key *location)
1077 {
1078 const char *name = dentry->d_name.name;
1079 int namelen = dentry->d_name.len;
1080 struct btrfs_dir_item *di;
1081 struct btrfs_path *path;
1082 struct btrfs_root *root = BTRFS_I(dir)->root;
1083 int ret = 0;
1084
1085 if (namelen == 1 && strcmp(name, ".") == 0) {
1086 location->objectid = dir->i_ino;
1087 location->type = BTRFS_INODE_ITEM_KEY;
1088 location->offset = 0;
1089 return 0;
1090 }
1091 path = btrfs_alloc_path();
1092 BUG_ON(!path);
1093
1094 if (namelen == 2 && strcmp(name, "..") == 0) {
1095 struct btrfs_key key;
1096 struct extent_buffer *leaf;
1097 u32 nritems;
1098 int slot;
1099
1100 key.objectid = dir->i_ino;
1101 btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
1102 key.offset = 0;
1103 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1104 BUG_ON(ret == 0);
1105 ret = 0;
1106
1107 leaf = path->nodes[0];
1108 slot = path->slots[0];
1109 nritems = btrfs_header_nritems(leaf);
1110 if (slot >= nritems)
1111 goto out_err;
1112
1113 btrfs_item_key_to_cpu(leaf, &key, slot);
1114 if (key.objectid != dir->i_ino ||
1115 key.type != BTRFS_INODE_REF_KEY) {
1116 goto out_err;
1117 }
1118 location->objectid = key.offset;
1119 location->type = BTRFS_INODE_ITEM_KEY;
1120 location->offset = 0;
1121 goto out;
1122 }
1123
1124 di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
1125 namelen, 0);
1126 if (IS_ERR(di))
1127 ret = PTR_ERR(di);
1128 if (!di || IS_ERR(di)) {
1129 goto out_err;
1130 }
1131 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
1132 out:
1133 btrfs_free_path(path);
1134 return ret;
1135 out_err:
1136 location->objectid = 0;
1137 goto out;
1138 }
1139
1140 /*
1141 * when we hit a tree root in a directory, the btrfs part of the inode
1142 * needs to be changed to reflect the root directory of the tree root. This
1143 * is kind of like crossing a mount point.
1144 */
1145 static int fixup_tree_root_location(struct btrfs_root *root,
1146 struct btrfs_key *location,
1147 struct btrfs_root **sub_root,
1148 struct dentry *dentry)
1149 {
1150 struct btrfs_path *path;
1151 struct btrfs_root_item *ri;
1152
1153 if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
1154 return 0;
1155 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1156 return 0;
1157
1158 path = btrfs_alloc_path();
1159 BUG_ON(!path);
1160 mutex_lock(&root->fs_info->fs_mutex);
1161
1162 *sub_root = btrfs_read_fs_root(root->fs_info, location,
1163 dentry->d_name.name,
1164 dentry->d_name.len);
1165 if (IS_ERR(*sub_root))
1166 return PTR_ERR(*sub_root);
1167
1168 ri = &(*sub_root)->root_item;
1169 location->objectid = btrfs_root_dirid(ri);
1170 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
1171 location->offset = 0;
1172
1173 btrfs_free_path(path);
1174 mutex_unlock(&root->fs_info->fs_mutex);
1175 return 0;
1176 }
1177
1178 static int btrfs_init_locked_inode(struct inode *inode, void *p)
1179 {
1180 struct btrfs_iget_args *args = p;
1181 inode->i_ino = args->ino;
1182 BTRFS_I(inode)->root = args->root;
1183 extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
1184 inode->i_mapping, GFP_NOFS);
1185 return 0;
1186 }
1187
1188 static int btrfs_find_actor(struct inode *inode, void *opaque)
1189 {
1190 struct btrfs_iget_args *args = opaque;
1191 return (args->ino == inode->i_ino &&
1192 args->root == BTRFS_I(inode)->root);
1193 }
1194
1195 struct inode *btrfs_ilookup(struct super_block *s, u64 objectid,
1196 u64 root_objectid)
1197 {
1198 struct btrfs_iget_args args;
1199 args.ino = objectid;
1200 args.root = btrfs_lookup_fs_root(btrfs_sb(s)->fs_info, root_objectid);
1201
1202 if (!args.root)
1203 return NULL;
1204
1205 return ilookup5(s, objectid, btrfs_find_actor, (void *)&args);
1206 }
1207
1208 struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
1209 struct btrfs_root *root)
1210 {
1211 struct inode *inode;
1212 struct btrfs_iget_args args;
1213 args.ino = objectid;
1214 args.root = root;
1215
1216 inode = iget5_locked(s, objectid, btrfs_find_actor,
1217 btrfs_init_locked_inode,
1218 (void *)&args);
1219 return inode;
1220 }
1221
1222 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
1223 struct nameidata *nd)
1224 {
1225 struct inode * inode;
1226 struct btrfs_inode *bi = BTRFS_I(dir);
1227 struct btrfs_root *root = bi->root;
1228 struct btrfs_root *sub_root = root;
1229 struct btrfs_key location;
1230 int ret;
1231
1232 if (dentry->d_name.len > BTRFS_NAME_LEN)
1233 return ERR_PTR(-ENAMETOOLONG);
1234
1235 mutex_lock(&root->fs_info->fs_mutex);
1236 ret = btrfs_inode_by_name(dir, dentry, &location);
1237 mutex_unlock(&root->fs_info->fs_mutex);
1238
1239 if (ret < 0)
1240 return ERR_PTR(ret);
1241
1242 inode = NULL;
1243 if (location.objectid) {
1244 ret = fixup_tree_root_location(root, &location, &sub_root,
1245 dentry);
1246 if (ret < 0)
1247 return ERR_PTR(ret);
1248 if (ret > 0)
1249 return ERR_PTR(-ENOENT);
1250 inode = btrfs_iget_locked(dir->i_sb, location.objectid,
1251 sub_root);
1252 if (!inode)
1253 return ERR_PTR(-EACCES);
1254 if (inode->i_state & I_NEW) {
1255 /* the inode and parent dir are two different roots */
1256 if (sub_root != root) {
1257 igrab(inode);
1258 sub_root->inode = inode;
1259 }
1260 BTRFS_I(inode)->root = sub_root;
1261 memcpy(&BTRFS_I(inode)->location, &location,
1262 sizeof(location));
1263 btrfs_read_locked_inode(inode);
1264 unlock_new_inode(inode);
1265 }
1266 }
1267 return d_splice_alias(inode, dentry);
1268 }
1269
1270 static unsigned char btrfs_filetype_table[] = {
1271 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
1272 };
1273
1274 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
1275 {
1276 struct inode *inode = filp->f_dentry->d_inode;
1277 struct btrfs_root *root = BTRFS_I(inode)->root;
1278 struct btrfs_item *item;
1279 struct btrfs_dir_item *di;
1280 struct btrfs_key key;
1281 struct btrfs_key found_key;
1282 struct btrfs_path *path;
1283 int ret;
1284 u32 nritems;
1285 struct extent_buffer *leaf;
1286 int slot;
1287 int advance;
1288 unsigned char d_type;
1289 int over = 0;
1290 u32 di_cur;
1291 u32 di_total;
1292 u32 di_len;
1293 int key_type = BTRFS_DIR_INDEX_KEY;
1294 char tmp_name[32];
1295 char *name_ptr;
1296 int name_len;
1297
1298 /* FIXME, use a real flag for deciding about the key type */
1299 if (root->fs_info->tree_root == root)
1300 key_type = BTRFS_DIR_ITEM_KEY;
1301
1302 /* special case for "." */
1303 if (filp->f_pos == 0) {
1304 over = filldir(dirent, ".", 1,
1305 1, inode->i_ino,
1306 DT_DIR);
1307 if (over)
1308 return 0;
1309 filp->f_pos = 1;
1310 }
1311
1312 mutex_lock(&root->fs_info->fs_mutex);
1313 key.objectid = inode->i_ino;
1314 path = btrfs_alloc_path();
1315 path->reada = 2;
1316
1317 /* special case for .., just use the back ref */
1318 if (filp->f_pos == 1) {
1319 btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
1320 key.offset = 0;
1321 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1322 BUG_ON(ret == 0);
1323 leaf = path->nodes[0];
1324 slot = path->slots[0];
1325 nritems = btrfs_header_nritems(leaf);
1326 if (slot >= nritems) {
1327 btrfs_release_path(root, path);
1328 goto read_dir_items;
1329 }
1330 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1331 btrfs_release_path(root, path);
1332 if (found_key.objectid != key.objectid ||
1333 found_key.type != BTRFS_INODE_REF_KEY)
1334 goto read_dir_items;
1335 over = filldir(dirent, "..", 2,
1336 2, found_key.offset, DT_DIR);
1337 if (over)
1338 goto nopos;
1339 filp->f_pos = 2;
1340 }
1341
1342 read_dir_items:
1343 btrfs_set_key_type(&key, key_type);
1344 key.offset = filp->f_pos;
1345
1346 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1347 if (ret < 0)
1348 goto err;
1349 advance = 0;
1350 while(1) {
1351 leaf = path->nodes[0];
1352 nritems = btrfs_header_nritems(leaf);
1353 slot = path->slots[0];
1354 if (advance || slot >= nritems) {
1355 if (slot >= nritems -1) {
1356 ret = btrfs_next_leaf(root, path);
1357 if (ret)
1358 break;
1359 leaf = path->nodes[0];
1360 nritems = btrfs_header_nritems(leaf);
1361 slot = path->slots[0];
1362 } else {
1363 slot++;
1364 path->slots[0]++;
1365 }
1366 }
1367 advance = 1;
1368 item = btrfs_item_nr(leaf, slot);
1369 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1370
1371 if (found_key.objectid != key.objectid)
1372 break;
1373 if (btrfs_key_type(&found_key) != key_type)
1374 break;
1375 if (found_key.offset < filp->f_pos)
1376 continue;
1377
1378 filp->f_pos = found_key.offset;
1379 advance = 1;
1380 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
1381 di_cur = 0;
1382 di_total = btrfs_item_size(leaf, item);
1383 while(di_cur < di_total) {
1384 struct btrfs_key location;
1385
1386 name_len = btrfs_dir_name_len(leaf, di);
1387 if (name_len < 32) {
1388 name_ptr = tmp_name;
1389 } else {
1390 name_ptr = kmalloc(name_len, GFP_NOFS);
1391 BUG_ON(!name_ptr);
1392 }
1393 read_extent_buffer(leaf, name_ptr,
1394 (unsigned long)(di + 1), name_len);
1395
1396 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
1397 btrfs_dir_item_key_to_cpu(leaf, di, &location);
1398 over = filldir(dirent, name_ptr, name_len,
1399 found_key.offset,
1400 location.objectid,
1401 d_type);
1402
1403 if (name_ptr != tmp_name)
1404 kfree(name_ptr);
1405
1406 if (over)
1407 goto nopos;
1408 di_len = btrfs_dir_name_len(leaf, di) +
1409 btrfs_dir_data_len(leaf, di) +sizeof(*di);
1410 di_cur += di_len;
1411 di = (struct btrfs_dir_item *)((char *)di + di_len);
1412 }
1413 }
1414 filp->f_pos++;
1415 nopos:
1416 ret = 0;
1417 err:
1418 btrfs_release_path(root, path);
1419 btrfs_free_path(path);
1420 mutex_unlock(&root->fs_info->fs_mutex);
1421 return ret;
1422 }
1423
1424 int btrfs_write_inode(struct inode *inode, int wait)
1425 {
1426 struct btrfs_root *root = BTRFS_I(inode)->root;
1427 struct btrfs_trans_handle *trans;
1428 int ret = 0;
1429
1430 if (wait) {
1431 mutex_lock(&root->fs_info->fs_mutex);
1432 trans = btrfs_start_transaction(root, 1);
1433 btrfs_set_trans_block_group(trans, inode);
1434 ret = btrfs_commit_transaction(trans, root);
1435 mutex_unlock(&root->fs_info->fs_mutex);
1436 }
1437 return ret;
1438 }
1439
1440 /*
1441 * This is somewhat expensive, updating the tree every time the
1442 * inode changes. But, it is most likely to find the inode in cache.
1443 * FIXME, needs more benchmarking...there are no reasons other than performance
1444 * to keep or drop this code.
1445 */
1446 void btrfs_dirty_inode(struct inode *inode)
1447 {
1448 struct btrfs_root *root = BTRFS_I(inode)->root;
1449 struct btrfs_trans_handle *trans;
1450
1451 mutex_lock(&root->fs_info->fs_mutex);
1452 trans = btrfs_start_transaction(root, 1);
1453 btrfs_set_trans_block_group(trans, inode);
1454 btrfs_update_inode(trans, root, inode);
1455 btrfs_end_transaction(trans, root);
1456 mutex_unlock(&root->fs_info->fs_mutex);
1457 }
1458
1459 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
1460 struct btrfs_root *root,
1461 u64 objectid,
1462 struct btrfs_block_group_cache *group,
1463 int mode)
1464 {
1465 struct inode *inode;
1466 struct btrfs_inode_item *inode_item;
1467 struct btrfs_key *location;
1468 struct btrfs_path *path;
1469 int ret;
1470 int owner;
1471
1472 path = btrfs_alloc_path();
1473 BUG_ON(!path);
1474
1475 inode = new_inode(root->fs_info->sb);
1476 if (!inode)
1477 return ERR_PTR(-ENOMEM);
1478
1479 extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
1480 inode->i_mapping, GFP_NOFS);
1481 BTRFS_I(inode)->root = root;
1482
1483 if (mode & S_IFDIR)
1484 owner = 0;
1485 else
1486 owner = 1;
1487 group = btrfs_find_block_group(root, group, 0, 0, owner);
1488 BTRFS_I(inode)->block_group = group;
1489 BTRFS_I(inode)->flags = 0;
1490 ret = btrfs_insert_empty_inode(trans, root, path, objectid);
1491 if (ret)
1492 goto fail;
1493
1494 inode->i_uid = current->fsuid;
1495 inode->i_gid = current->fsgid;
1496 inode->i_mode = mode;
1497 inode->i_ino = objectid;
1498 inode->i_blocks = 0;
1499 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1500 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1501 struct btrfs_inode_item);
1502 fill_inode_item(path->nodes[0], inode_item, inode);
1503 btrfs_mark_buffer_dirty(path->nodes[0]);
1504 btrfs_free_path(path);
1505
1506 location = &BTRFS_I(inode)->location;
1507 location->objectid = objectid;
1508 location->offset = 0;
1509 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
1510
1511 insert_inode_hash(inode);
1512 return inode;
1513 fail:
1514 btrfs_free_path(path);
1515 return ERR_PTR(ret);
1516 }
1517
1518 static inline u8 btrfs_inode_type(struct inode *inode)
1519 {
1520 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
1521 }
1522
1523 static int btrfs_add_link(struct btrfs_trans_handle *trans,
1524 struct dentry *dentry, struct inode *inode)
1525 {
1526 int ret;
1527 struct btrfs_key key;
1528 struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
1529 struct inode *parent_inode;
1530
1531 key.objectid = inode->i_ino;
1532 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
1533 key.offset = 0;
1534
1535 ret = btrfs_insert_dir_item(trans, root,
1536 dentry->d_name.name, dentry->d_name.len,
1537 dentry->d_parent->d_inode->i_ino,
1538 &key, btrfs_inode_type(inode));
1539 if (ret == 0) {
1540 ret = btrfs_insert_inode_ref(trans, root,
1541 dentry->d_name.name,
1542 dentry->d_name.len,
1543 inode->i_ino,
1544 dentry->d_parent->d_inode->i_ino);
1545 parent_inode = dentry->d_parent->d_inode;
1546 parent_inode->i_size += dentry->d_name.len * 2;
1547 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
1548 ret = btrfs_update_inode(trans, root,
1549 dentry->d_parent->d_inode);
1550 }
1551 return ret;
1552 }
1553
1554 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
1555 struct dentry *dentry, struct inode *inode)
1556 {
1557 int err = btrfs_add_link(trans, dentry, inode);
1558 if (!err) {
1559 d_instantiate(dentry, inode);
1560 return 0;
1561 }
1562 if (err > 0)
1563 err = -EEXIST;
1564 return err;
1565 }
1566
1567 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
1568 int mode, dev_t rdev)
1569 {
1570 struct btrfs_trans_handle *trans;
1571 struct btrfs_root *root = BTRFS_I(dir)->root;
1572 struct inode *inode = NULL;
1573 int err;
1574 int drop_inode = 0;
1575 u64 objectid;
1576 unsigned long nr = 0;
1577
1578 if (!new_valid_dev(rdev))
1579 return -EINVAL;
1580
1581 mutex_lock(&root->fs_info->fs_mutex);
1582 err = btrfs_check_free_space(root, 1, 0);
1583 if (err)
1584 goto fail;
1585
1586 trans = btrfs_start_transaction(root, 1);
1587 btrfs_set_trans_block_group(trans, dir);
1588
1589 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1590 if (err) {
1591 err = -ENOSPC;
1592 goto out_unlock;
1593 }
1594
1595 inode = btrfs_new_inode(trans, root, objectid,
1596 BTRFS_I(dir)->block_group, mode);
1597 err = PTR_ERR(inode);
1598 if (IS_ERR(inode))
1599 goto out_unlock;
1600
1601 btrfs_set_trans_block_group(trans, inode);
1602 err = btrfs_add_nondir(trans, dentry, inode);
1603 if (err)
1604 drop_inode = 1;
1605 else {
1606 inode->i_op = &btrfs_special_inode_operations;
1607 init_special_inode(inode, inode->i_mode, rdev);
1608 btrfs_update_inode(trans, root, inode);
1609 }
1610 dir->i_sb->s_dirt = 1;
1611 btrfs_update_inode_block_group(trans, inode);
1612 btrfs_update_inode_block_group(trans, dir);
1613 out_unlock:
1614 nr = trans->blocks_used;
1615 btrfs_end_transaction(trans, root);
1616 fail:
1617 mutex_unlock(&root->fs_info->fs_mutex);
1618
1619 if (drop_inode) {
1620 inode_dec_link_count(inode);
1621 iput(inode);
1622 }
1623 btrfs_btree_balance_dirty(root, nr);
1624 btrfs_throttle(root);
1625 return err;
1626 }
1627
1628 static int btrfs_create(struct inode *dir, struct dentry *dentry,
1629 int mode, struct nameidata *nd)
1630 {
1631 struct btrfs_trans_handle *trans;
1632 struct btrfs_root *root = BTRFS_I(dir)->root;
1633 struct inode *inode = NULL;
1634 int err;
1635 int drop_inode = 0;
1636 unsigned long nr = 0;
1637 u64 objectid;
1638
1639 mutex_lock(&root->fs_info->fs_mutex);
1640 err = btrfs_check_free_space(root, 1, 0);
1641 if (err)
1642 goto fail;
1643 trans = btrfs_start_transaction(root, 1);
1644 btrfs_set_trans_block_group(trans, dir);
1645
1646 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1647 if (err) {
1648 err = -ENOSPC;
1649 goto out_unlock;
1650 }
1651
1652 inode = btrfs_new_inode(trans, root, objectid,
1653 BTRFS_I(dir)->block_group, mode);
1654 err = PTR_ERR(inode);
1655 if (IS_ERR(inode))
1656 goto out_unlock;
1657
1658 btrfs_set_trans_block_group(trans, inode);
1659 err = btrfs_add_nondir(trans, dentry, inode);
1660 if (err)
1661 drop_inode = 1;
1662 else {
1663 inode->i_mapping->a_ops = &btrfs_aops;
1664 inode->i_fop = &btrfs_file_operations;
1665 inode->i_op = &btrfs_file_inode_operations;
1666 extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
1667 inode->i_mapping, GFP_NOFS);
1668 BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
1669 }
1670 dir->i_sb->s_dirt = 1;
1671 btrfs_update_inode_block_group(trans, inode);
1672 btrfs_update_inode_block_group(trans, dir);
1673 out_unlock:
1674 nr = trans->blocks_used;
1675 btrfs_end_transaction(trans, root);
1676 fail:
1677 mutex_unlock(&root->fs_info->fs_mutex);
1678
1679 if (drop_inode) {
1680 inode_dec_link_count(inode);
1681 iput(inode);
1682 }
1683 btrfs_btree_balance_dirty(root, nr);
1684 btrfs_throttle(root);
1685 return err;
1686 }
1687
1688 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
1689 struct dentry *dentry)
1690 {
1691 struct btrfs_trans_handle *trans;
1692 struct btrfs_root *root = BTRFS_I(dir)->root;
1693 struct inode *inode = old_dentry->d_inode;
1694 unsigned long nr = 0;
1695 int err;
1696 int drop_inode = 0;
1697
1698 if (inode->i_nlink == 0)
1699 return -ENOENT;
1700
1701 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
1702 inode->i_nlink++;
1703 #else
1704 inc_nlink(inode);
1705 #endif
1706 mutex_lock(&root->fs_info->fs_mutex);
1707 err = btrfs_check_free_space(root, 1, 0);
1708 if (err)
1709 goto fail;
1710 trans = btrfs_start_transaction(root, 1);
1711
1712 btrfs_set_trans_block_group(trans, dir);
1713 atomic_inc(&inode->i_count);
1714 err = btrfs_add_nondir(trans, dentry, inode);
1715
1716 if (err)
1717 drop_inode = 1;
1718
1719 dir->i_sb->s_dirt = 1;
1720 btrfs_update_inode_block_group(trans, dir);
1721 err = btrfs_update_inode(trans, root, inode);
1722
1723 if (err)
1724 drop_inode = 1;
1725
1726 nr = trans->blocks_used;
1727 btrfs_end_transaction(trans, root);
1728 fail:
1729 mutex_unlock(&root->fs_info->fs_mutex);
1730
1731 if (drop_inode) {
1732 inode_dec_link_count(inode);
1733 iput(inode);
1734 }
1735 btrfs_btree_balance_dirty(root, nr);
1736 btrfs_throttle(root);
1737 return err;
1738 }
1739
1740 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
1741 {
1742 struct inode *inode;
1743 struct btrfs_trans_handle *trans;
1744 struct btrfs_root *root = BTRFS_I(dir)->root;
1745 int err = 0;
1746 int drop_on_err = 0;
1747 u64 objectid;
1748 unsigned long nr = 1;
1749
1750 mutex_lock(&root->fs_info->fs_mutex);
1751 err = btrfs_check_free_space(root, 1, 0);
1752 if (err)
1753 goto out_unlock;
1754
1755 trans = btrfs_start_transaction(root, 1);
1756 btrfs_set_trans_block_group(trans, dir);
1757
1758 if (IS_ERR(trans)) {
1759 err = PTR_ERR(trans);
1760 goto out_unlock;
1761 }
1762
1763 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1764 if (err) {
1765 err = -ENOSPC;
1766 goto out_unlock;
1767 }
1768
1769 inode = btrfs_new_inode(trans, root, objectid,
1770 BTRFS_I(dir)->block_group, S_IFDIR | mode);
1771 if (IS_ERR(inode)) {
1772 err = PTR_ERR(inode);
1773 goto out_fail;
1774 }
1775
1776 drop_on_err = 1;
1777 inode->i_op = &btrfs_dir_inode_operations;
1778 inode->i_fop = &btrfs_dir_file_operations;
1779 btrfs_set_trans_block_group(trans, inode);
1780
1781 inode->i_size = 0;
1782 err = btrfs_update_inode(trans, root, inode);
1783 if (err)
1784 goto out_fail;
1785
1786 err = btrfs_add_link(trans, dentry, inode);
1787 if (err)
1788 goto out_fail;
1789
1790 d_instantiate(dentry, inode);
1791 drop_on_err = 0;
1792 dir->i_sb->s_dirt = 1;
1793 btrfs_update_inode_block_group(trans, inode);
1794 btrfs_update_inode_block_group(trans, dir);
1795
1796 out_fail:
1797 nr = trans->blocks_used;
1798 btrfs_end_transaction(trans, root);
1799
1800 out_unlock:
1801 mutex_unlock(&root->fs_info->fs_mutex);
1802 if (drop_on_err)
1803 iput(inode);
1804 btrfs_btree_balance_dirty(root, nr);
1805 btrfs_throttle(root);
1806 return err;
1807 }
1808
1809 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
1810 size_t page_offset, u64 start, u64 end,
1811 int create)
1812 {
1813 int ret;
1814 int err = 0;
1815 u64 bytenr;
1816 u64 extent_start = 0;
1817 u64 extent_end = 0;
1818 u64 objectid = inode->i_ino;
1819 u32 found_type;
1820 int failed_insert = 0;
1821 struct btrfs_path *path;
1822 struct btrfs_root *root = BTRFS_I(inode)->root;
1823 struct btrfs_file_extent_item *item;
1824 struct extent_buffer *leaf;
1825 struct btrfs_key found_key;
1826 struct extent_map *em = NULL;
1827 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1828 struct btrfs_trans_handle *trans = NULL;
1829
1830 path = btrfs_alloc_path();
1831 BUG_ON(!path);
1832 mutex_lock(&root->fs_info->fs_mutex);
1833
1834 again:
1835 em = lookup_extent_mapping(em_tree, start, end);
1836 if (em) {
1837 if (em->start > start) {
1838 printk("get_extent start %Lu em start %Lu\n",
1839 start, em->start);
1840 WARN_ON(1);
1841 }
1842 goto out;
1843 }
1844 if (!em) {
1845 em = alloc_extent_map(GFP_NOFS);
1846 if (!em) {
1847 err = -ENOMEM;
1848 goto out;
1849 }
1850 em->start = EXTENT_MAP_HOLE;
1851 em->end = EXTENT_MAP_HOLE;
1852 }
1853 em->bdev = inode->i_sb->s_bdev;
1854 ret = btrfs_lookup_file_extent(trans, root, path,
1855 objectid, start, trans != NULL);
1856 if (ret < 0) {
1857 err = ret;
1858 goto out;
1859 }
1860
1861 if (ret != 0) {
1862 if (path->slots[0] == 0)
1863 goto not_found;
1864 path->slots[0]--;
1865 }
1866
1867 leaf = path->nodes[0];
1868 item = btrfs_item_ptr(leaf, path->slots[0],
1869 struct btrfs_file_extent_item);
1870 /* are we inside the extent that was found? */
1871 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1872 found_type = btrfs_key_type(&found_key);
1873 if (found_key.objectid != objectid ||
1874 found_type != BTRFS_EXTENT_DATA_KEY) {
1875 goto not_found;
1876 }
1877
1878 found_type = btrfs_file_extent_type(leaf, item);
1879 extent_start = found_key.offset;
1880 if (found_type == BTRFS_FILE_EXTENT_REG) {
1881 extent_end = extent_start +
1882 btrfs_file_extent_num_bytes(leaf, item);
1883 err = 0;
1884 if (start < extent_start || start >= extent_end) {
1885 em->start = start;
1886 if (start < extent_start) {
1887 if (end < extent_start)
1888 goto not_found;
1889 em->end = extent_end - 1;
1890 } else {
1891 em->end = end;
1892 }
1893 goto not_found_em;
1894 }
1895 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
1896 if (bytenr == 0) {
1897 em->start = extent_start;
1898 em->end = extent_end - 1;
1899 em->block_start = EXTENT_MAP_HOLE;
1900 em->block_end = EXTENT_MAP_HOLE;
1901 goto insert;
1902 }
1903 bytenr += btrfs_file_extent_offset(leaf, item);
1904 em->block_start = bytenr;
1905 em->block_end = em->block_start +
1906 btrfs_file_extent_num_bytes(leaf, item) - 1;
1907 em->start = extent_start;
1908 em->end = extent_end - 1;
1909 goto insert;
1910 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
1911 unsigned long ptr;
1912 char *map;
1913 size_t size;
1914 size_t extent_offset;
1915 size_t copy_size;
1916
1917 size = btrfs_file_extent_inline_len(leaf, btrfs_item_nr(leaf,
1918 path->slots[0]));
1919 extent_end = (extent_start + size - 1) |
1920 ((u64)root->sectorsize - 1);
1921 if (start < extent_start || start >= extent_end) {
1922 em->start = start;
1923 if (start < extent_start) {
1924 if (end < extent_start)
1925 goto not_found;
1926 em->end = extent_end;
1927 } else {
1928 em->end = end;
1929 }
1930 goto not_found_em;
1931 }
1932 em->block_start = EXTENT_MAP_INLINE;
1933 em->block_end = EXTENT_MAP_INLINE;
1934
1935 if (!page) {
1936 em->start = extent_start;
1937 em->end = extent_start + size - 1;
1938 goto out;
1939 }
1940
1941 extent_offset = ((u64)page->index << PAGE_CACHE_SHIFT) -
1942 extent_start + page_offset;
1943 copy_size = min_t(u64, PAGE_CACHE_SIZE - page_offset,
1944 size - extent_offset);
1945 em->start = extent_start + extent_offset;
1946 em->end = (em->start + copy_size -1) |
1947 ((u64)root->sectorsize -1);
1948 map = kmap(page);
1949 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
1950 if (create == 0 && !PageUptodate(page)) {
1951 read_extent_buffer(leaf, map + page_offset, ptr,
1952 copy_size);
1953 flush_dcache_page(page);
1954 } else if (create && PageUptodate(page)) {
1955 if (!trans) {
1956 kunmap(page);
1957 free_extent_map(em);
1958 em = NULL;
1959 btrfs_release_path(root, path);
1960 trans = btrfs_start_transaction(root, 1);
1961 goto again;
1962 }
1963 write_extent_buffer(leaf, map + page_offset, ptr,
1964 copy_size);
1965 btrfs_mark_buffer_dirty(leaf);
1966 }
1967 kunmap(page);
1968 set_extent_uptodate(em_tree, em->start, em->end, GFP_NOFS);
1969 goto insert;
1970 } else {
1971 printk("unkknown found_type %d\n", found_type);
1972 WARN_ON(1);
1973 }
1974 not_found:
1975 em->start = start;
1976 em->end = end;
1977 not_found_em:
1978 em->block_start = EXTENT_MAP_HOLE;
1979 em->block_end = EXTENT_MAP_HOLE;
1980 insert:
1981 btrfs_release_path(root, path);
1982 if (em->start > start || em->end < start) {
1983 printk("bad extent! em: [%Lu %Lu] passed [%Lu %Lu]\n", em->start, em->end, start, end);
1984 err = -EIO;
1985 goto out;
1986 }
1987 ret = add_extent_mapping(em_tree, em);
1988 if (ret == -EEXIST) {
1989 free_extent_map(em);
1990 em = NULL;
1991 if (0 && failed_insert == 1) {
1992 btrfs_drop_extent_cache(inode, start, end);
1993 }
1994 failed_insert++;
1995 if (failed_insert > 5) {
1996 printk("failing to insert %Lu %Lu\n", start, end);
1997 err = -EIO;
1998 goto out;
1999 }
2000 goto again;
2001 }
2002 err = 0;
2003 out:
2004 btrfs_free_path(path);
2005 if (trans) {
2006 ret = btrfs_end_transaction(trans, root);
2007 if (!err)
2008 err = ret;
2009 }
2010 mutex_unlock(&root->fs_info->fs_mutex);
2011 if (err) {
2012 free_extent_map(em);
2013 WARN_ON(1);
2014 return ERR_PTR(err);
2015 }
2016 return em;
2017 }
2018
2019 static sector_t btrfs_bmap(struct address_space *mapping, sector_t iblock)
2020 {
2021 return extent_bmap(mapping, iblock, btrfs_get_extent);
2022 }
2023
2024 int btrfs_readpage(struct file *file, struct page *page)
2025 {
2026 struct extent_map_tree *tree;
2027 tree = &BTRFS_I(page->mapping->host)->extent_tree;
2028 return extent_read_full_page(tree, page, btrfs_get_extent);
2029 }
2030
2031 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
2032 {
2033 struct extent_map_tree *tree;
2034
2035
2036 if (current->flags & PF_MEMALLOC) {
2037 redirty_page_for_writepage(wbc, page);
2038 unlock_page(page);
2039 return 0;
2040 }
2041 tree = &BTRFS_I(page->mapping->host)->extent_tree;
2042 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
2043 }
2044
2045 static int btrfs_writepages(struct address_space *mapping,
2046 struct writeback_control *wbc)
2047 {
2048 struct extent_map_tree *tree;
2049 tree = &BTRFS_I(mapping->host)->extent_tree;
2050 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
2051 }
2052
2053 static int
2054 btrfs_readpages(struct file *file, struct address_space *mapping,
2055 struct list_head *pages, unsigned nr_pages)
2056 {
2057 struct extent_map_tree *tree;
2058 tree = &BTRFS_I(mapping->host)->extent_tree;
2059 return extent_readpages(tree, mapping, pages, nr_pages,
2060 btrfs_get_extent);
2061 }
2062
2063 static int btrfs_releasepage(struct page *page, gfp_t unused_gfp_flags)
2064 {
2065 struct extent_map_tree *tree;
2066 int ret;
2067
2068 tree = &BTRFS_I(page->mapping->host)->extent_tree;
2069 ret = try_release_extent_mapping(tree, page);
2070 if (ret == 1) {
2071 ClearPagePrivate(page);
2072 set_page_private(page, 0);
2073 page_cache_release(page);
2074 }
2075 return ret;
2076 }
2077
2078 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
2079 {
2080 struct extent_map_tree *tree;
2081
2082 tree = &BTRFS_I(page->mapping->host)->extent_tree;
2083 extent_invalidatepage(tree, page, offset);
2084 btrfs_releasepage(page, GFP_NOFS);
2085 }
2086
2087 /*
2088 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
2089 * called from a page fault handler when a page is first dirtied. Hence we must
2090 * be careful to check for EOF conditions here. We set the page up correctly
2091 * for a written page which means we get ENOSPC checking when writing into
2092 * holes and correct delalloc and unwritten extent mapping on filesystems that
2093 * support these features.
2094 *
2095 * We are not allowed to take the i_mutex here so we have to play games to
2096 * protect against truncate races as the page could now be beyond EOF. Because
2097 * vmtruncate() writes the inode size before removing pages, once we have the
2098 * page lock we can determine safely if the page is beyond EOF. If it is not
2099 * beyond EOF, then the page is guaranteed safe against truncation until we
2100 * unlock the page.
2101 */
2102 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
2103 {
2104 struct inode *inode = fdentry(vma->vm_file)->d_inode;
2105 struct btrfs_root *root = BTRFS_I(inode)->root;
2106 unsigned long end;
2107 loff_t size;
2108 int ret;
2109 u64 page_start;
2110
2111 mutex_lock(&root->fs_info->fs_mutex);
2112 ret = btrfs_check_free_space(root, PAGE_CACHE_SIZE, 0);
2113 mutex_unlock(&root->fs_info->fs_mutex);
2114 if (ret)
2115 goto out;
2116
2117 ret = -EINVAL;
2118
2119 lock_page(page);
2120 wait_on_page_writeback(page);
2121 size = i_size_read(inode);
2122 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2123
2124 if ((page->mapping != inode->i_mapping) ||
2125 (page_start > size)) {
2126 /* page got truncated out from underneath us */
2127 goto out_unlock;
2128 }
2129
2130 /* page is wholly or partially inside EOF */
2131 if (page_start + PAGE_CACHE_SIZE > size)
2132 end = size & ~PAGE_CACHE_MASK;
2133 else
2134 end = PAGE_CACHE_SIZE;
2135
2136 ret = btrfs_cow_one_page(inode, page, end);
2137
2138 out_unlock:
2139 unlock_page(page);
2140 out:
2141 return ret;
2142 }
2143
2144 static void btrfs_truncate(struct inode *inode)
2145 {
2146 struct btrfs_root *root = BTRFS_I(inode)->root;
2147 int ret;
2148 struct btrfs_trans_handle *trans;
2149 unsigned long nr;
2150
2151 if (!S_ISREG(inode->i_mode))
2152 return;
2153 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
2154 return;
2155
2156 btrfs_truncate_page(inode->i_mapping, inode->i_size);
2157
2158 mutex_lock(&root->fs_info->fs_mutex);
2159 trans = btrfs_start_transaction(root, 1);
2160 btrfs_set_trans_block_group(trans, inode);
2161
2162 /* FIXME, add redo link to tree so we don't leak on crash */
2163 ret = btrfs_truncate_in_trans(trans, root, inode);
2164 btrfs_update_inode(trans, root, inode);
2165 nr = trans->blocks_used;
2166
2167 ret = btrfs_end_transaction(trans, root);
2168 BUG_ON(ret);
2169 mutex_unlock(&root->fs_info->fs_mutex);
2170 btrfs_btree_balance_dirty(root, nr);
2171 btrfs_throttle(root);
2172 }
2173
2174 static int noinline create_subvol(struct btrfs_root *root, char *name,
2175 int namelen)
2176 {
2177 struct btrfs_trans_handle *trans;
2178 struct btrfs_key key;
2179 struct btrfs_root_item root_item;
2180 struct btrfs_inode_item *inode_item;
2181 struct extent_buffer *leaf;
2182 struct btrfs_root *new_root = root;
2183 struct inode *inode;
2184 struct inode *dir;
2185 int ret;
2186 int err;
2187 u64 objectid;
2188 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
2189 unsigned long nr = 1;
2190
2191 mutex_lock(&root->fs_info->fs_mutex);
2192 ret = btrfs_check_free_space(root, 1, 0);
2193 if (ret)
2194 goto fail_commit;
2195
2196 trans = btrfs_start_transaction(root, 1);
2197 BUG_ON(!trans);
2198
2199 ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
2200 0, &objectid);
2201 if (ret)
2202 goto fail;
2203
2204 leaf = __btrfs_alloc_free_block(trans, root, root->leafsize,
2205 objectid, trans->transid, 0, 0,
2206 0, 0);
2207 if (IS_ERR(leaf))
2208 return PTR_ERR(leaf);
2209
2210 btrfs_set_header_nritems(leaf, 0);
2211 btrfs_set_header_level(leaf, 0);
2212 btrfs_set_header_bytenr(leaf, leaf->start);
2213 btrfs_set_header_generation(leaf, trans->transid);
2214 btrfs_set_header_owner(leaf, objectid);
2215
2216 write_extent_buffer(leaf, root->fs_info->fsid,
2217 (unsigned long)btrfs_header_fsid(leaf),
2218 BTRFS_FSID_SIZE);
2219 btrfs_mark_buffer_dirty(leaf);
2220
2221 inode_item = &root_item.inode;
2222 memset(inode_item, 0, sizeof(*inode_item));
2223 inode_item->generation = cpu_to_le64(1);
2224 inode_item->size = cpu_to_le64(3);
2225 inode_item->nlink = cpu_to_le32(1);
2226 inode_item->nblocks = cpu_to_le64(1);
2227 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
2228
2229 btrfs_set_root_bytenr(&root_item, leaf->start);
2230 btrfs_set_root_level(&root_item, 0);
2231 btrfs_set_root_refs(&root_item, 1);
2232 btrfs_set_root_used(&root_item, 0);
2233
2234 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
2235 root_item.drop_level = 0;
2236
2237 free_extent_buffer(leaf);
2238 leaf = NULL;
2239
2240 btrfs_set_root_dirid(&root_item, new_dirid);
2241
2242 key.objectid = objectid;
2243 key.offset = 1;
2244 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
2245 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
2246 &root_item);
2247 if (ret)
2248 goto fail;
2249
2250 /*
2251 * insert the directory item
2252 */
2253 key.offset = (u64)-1;
2254 dir = root->fs_info->sb->s_root->d_inode;
2255 ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
2256 name, namelen, dir->i_ino, &key,
2257 BTRFS_FT_DIR);
2258 if (ret)
2259 goto fail;
2260
2261 ret = btrfs_insert_inode_ref(trans, root->fs_info->tree_root,
2262 name, namelen, objectid,
2263 root->fs_info->sb->s_root->d_inode->i_ino);
2264 if (ret)
2265 goto fail;
2266
2267 ret = btrfs_commit_transaction(trans, root);
2268 if (ret)
2269 goto fail_commit;
2270
2271 new_root = btrfs_read_fs_root(root->fs_info, &key, name, namelen);
2272 BUG_ON(!new_root);
2273
2274 trans = btrfs_start_transaction(new_root, 1);
2275 BUG_ON(!trans);
2276
2277 inode = btrfs_new_inode(trans, new_root, new_dirid,
2278 BTRFS_I(dir)->block_group, S_IFDIR | 0700);
2279 if (IS_ERR(inode))
2280 goto fail;
2281 inode->i_op = &btrfs_dir_inode_operations;
2282 inode->i_fop = &btrfs_dir_file_operations;
2283 new_root->inode = inode;
2284
2285 ret = btrfs_insert_inode_ref(trans, new_root, "..", 2, new_dirid,
2286 new_dirid);
2287 inode->i_nlink = 1;
2288 inode->i_size = 0;
2289 ret = btrfs_update_inode(trans, new_root, inode);
2290 if (ret)
2291 goto fail;
2292 fail:
2293 nr = trans->blocks_used;
2294 err = btrfs_commit_transaction(trans, new_root);
2295 if (err && !ret)
2296 ret = err;
2297 fail_commit:
2298 mutex_unlock(&root->fs_info->fs_mutex);
2299 btrfs_btree_balance_dirty(root, nr);
2300 btrfs_throttle(root);
2301 return ret;
2302 }
2303
2304 static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
2305 {
2306 struct btrfs_pending_snapshot *pending_snapshot;
2307 struct btrfs_trans_handle *trans;
2308 int ret;
2309 int err;
2310 unsigned long nr = 0;
2311
2312 if (!root->ref_cows)
2313 return -EINVAL;
2314
2315 mutex_lock(&root->fs_info->fs_mutex);
2316 ret = btrfs_check_free_space(root, 1, 0);
2317 if (ret)
2318 goto fail_unlock;
2319
2320 pending_snapshot = kmalloc(sizeof(*pending_snapshot), GFP_NOFS);
2321 if (!pending_snapshot) {
2322 ret = -ENOMEM;
2323 goto fail_unlock;
2324 }
2325 pending_snapshot->name = kstrndup(name, namelen, GFP_NOFS);
2326 if (!pending_snapshot->name) {
2327 ret = -ENOMEM;
2328 kfree(pending_snapshot);
2329 goto fail_unlock;
2330 }
2331 trans = btrfs_start_transaction(root, 1);
2332 BUG_ON(!trans);
2333
2334 pending_snapshot->root = root;
2335 list_add(&pending_snapshot->list,
2336 &trans->transaction->pending_snapshots);
2337 ret = btrfs_update_inode(trans, root, root->inode);
2338 err = btrfs_commit_transaction(trans, root);
2339
2340 fail_unlock:
2341 mutex_unlock(&root->fs_info->fs_mutex);
2342 btrfs_btree_balance_dirty(root, nr);
2343 btrfs_throttle(root);
2344 return ret;
2345 }
2346
2347 unsigned long btrfs_force_ra(struct address_space *mapping,
2348 struct file_ra_state *ra, struct file *file,
2349 pgoff_t offset, pgoff_t last_index)
2350 {
2351 pgoff_t req_size;
2352
2353 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
2354 req_size = last_index - offset + 1;
2355 offset = page_cache_readahead(mapping, ra, file, offset, req_size);
2356 return offset;
2357 #else
2358 req_size = min(last_index - offset + 1, (pgoff_t)128);
2359 page_cache_sync_readahead(mapping, ra, file, offset, req_size);
2360 return offset + req_size;
2361 #endif
2362 }
2363
2364 int btrfs_defrag_file(struct file *file) {
2365 struct inode *inode = fdentry(file)->d_inode;
2366 struct btrfs_root *root = BTRFS_I(inode)->root;
2367 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
2368 struct page *page;
2369 unsigned long last_index;
2370 unsigned long ra_index = 0;
2371 u64 page_start;
2372 u64 page_end;
2373 u64 delalloc_start;
2374 u64 existing_delalloc;
2375 unsigned long i;
2376 int ret;
2377
2378 mutex_lock(&root->fs_info->fs_mutex);
2379 ret = btrfs_check_free_space(root, inode->i_size, 0);
2380 mutex_unlock(&root->fs_info->fs_mutex);
2381 if (ret)
2382 return -ENOSPC;
2383
2384 mutex_lock(&inode->i_mutex);
2385 last_index = inode->i_size >> PAGE_CACHE_SHIFT;
2386 for (i = 0; i <= last_index; i++) {
2387 if (i == ra_index) {
2388 ra_index = btrfs_force_ra(inode->i_mapping,
2389 &file->f_ra,
2390 file, ra_index, last_index);
2391 }
2392 page = grab_cache_page(inode->i_mapping, i);
2393 if (!page)
2394 goto out_unlock;
2395 if (!PageUptodate(page)) {
2396 btrfs_readpage(NULL, page);
2397 lock_page(page);
2398 if (!PageUptodate(page)) {
2399 unlock_page(page);
2400 page_cache_release(page);
2401 goto out_unlock;
2402 }
2403 }
2404 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2405 page_end = page_start + PAGE_CACHE_SIZE - 1;
2406
2407 lock_extent(em_tree, page_start, page_end, GFP_NOFS);
2408 delalloc_start = page_start;
2409 existing_delalloc =
2410 count_range_bits(&BTRFS_I(inode)->extent_tree,
2411 &delalloc_start, page_end,
2412 PAGE_CACHE_SIZE, EXTENT_DELALLOC);
2413 set_extent_delalloc(em_tree, page_start,
2414 page_end, GFP_NOFS);
2415
2416 spin_lock(&root->fs_info->delalloc_lock);
2417 root->fs_info->delalloc_bytes += PAGE_CACHE_SIZE -
2418 existing_delalloc;
2419 spin_unlock(&root->fs_info->delalloc_lock);
2420
2421 unlock_extent(em_tree, page_start, page_end, GFP_NOFS);
2422 set_page_dirty(page);
2423 unlock_page(page);
2424 page_cache_release(page);
2425 balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);
2426 }
2427
2428 out_unlock:
2429 mutex_unlock(&inode->i_mutex);
2430 return 0;
2431 }
2432
2433 static int btrfs_ioctl_resize(struct btrfs_root *root, void __user *arg)
2434 {
2435 u64 new_size;
2436 u64 old_size;
2437 struct btrfs_ioctl_vol_args *vol_args;
2438 struct btrfs_trans_handle *trans;
2439 char *sizestr;
2440 int ret = 0;
2441 int namelen;
2442 int mod = 0;
2443
2444 vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS);
2445
2446 if (!vol_args)
2447 return -ENOMEM;
2448
2449 if (copy_from_user(vol_args, arg, sizeof(*vol_args))) {
2450 ret = -EFAULT;
2451 goto out;
2452 }
2453 namelen = strlen(vol_args->name);
2454 if (namelen > BTRFS_VOL_NAME_MAX) {
2455 ret = -EINVAL;
2456 goto out;
2457 }
2458
2459 sizestr = vol_args->name;
2460 if (!strcmp(sizestr, "max"))
2461 new_size = root->fs_info->sb->s_bdev->bd_inode->i_size;
2462 else {
2463 if (sizestr[0] == '-') {
2464 mod = -1;
2465 sizestr++;
2466 } else if (sizestr[0] == '+') {
2467 mod = 1;
2468 sizestr++;
2469 }
2470 new_size = btrfs_parse_size(sizestr);
2471 if (new_size == 0) {
2472 ret = -EINVAL;
2473 goto out;
2474 }
2475 }
2476
2477 mutex_lock(&root->fs_info->fs_mutex);
2478 old_size = btrfs_super_total_bytes(&root->fs_info->super_copy);
2479
2480 if (mod < 0) {
2481 if (new_size > old_size) {
2482 ret = -EINVAL;
2483 goto out_unlock;
2484 }
2485 new_size = old_size - new_size;
2486 } else if (mod > 0) {
2487 new_size = old_size + new_size;
2488 }
2489
2490 if (new_size < 256 * 1024 * 1024) {
2491 ret = -EINVAL;
2492 goto out_unlock;
2493 }
2494 if (new_size > root->fs_info->sb->s_bdev->bd_inode->i_size) {
2495 ret = -EFBIG;
2496 goto out_unlock;
2497 }
2498
2499 do_div(new_size, root->sectorsize);
2500 new_size *= root->sectorsize;
2501
2502 printk("new size is %Lu\n", new_size);
2503 if (new_size > old_size) {
2504 trans = btrfs_start_transaction(root, 1);
2505 ret = btrfs_grow_extent_tree(trans, root, new_size);
2506 btrfs_commit_transaction(trans, root);
2507 } else {
2508 ret = btrfs_shrink_extent_tree(root, new_size);
2509 }
2510
2511 out_unlock:
2512 mutex_unlock(&root->fs_info->fs_mutex);
2513 out:
2514 kfree(vol_args);
2515 return ret;
2516 }
2517
2518 static int noinline btrfs_ioctl_snap_create(struct btrfs_root *root,
2519 void __user *arg)
2520 {
2521 struct btrfs_ioctl_vol_args *vol_args;
2522 struct btrfs_dir_item *di;
2523 struct btrfs_path *path;
2524 u64 root_dirid;
2525 int namelen;
2526 int ret;
2527
2528 vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS);
2529
2530 if (!vol_args)
2531 return -ENOMEM;
2532
2533 if (copy_from_user(vol_args, arg, sizeof(*vol_args))) {
2534 ret = -EFAULT;
2535 goto out;
2536 }
2537
2538 namelen = strlen(vol_args->name);
2539 if (namelen > BTRFS_VOL_NAME_MAX) {
2540 ret = -EINVAL;
2541 goto out;
2542 }
2543 if (strchr(vol_args->name, '/')) {
2544 ret = -EINVAL;
2545 goto out;
2546 }
2547
2548 path = btrfs_alloc_path();
2549 if (!path) {
2550 ret = -ENOMEM;
2551 goto out;
2552 }
2553
2554 root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
2555 mutex_lock(&root->fs_info->fs_mutex);
2556 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
2557 path, root_dirid,
2558 vol_args->name, namelen, 0);
2559 mutex_unlock(&root->fs_info->fs_mutex);
2560 btrfs_free_path(path);
2561
2562 if (di && !IS_ERR(di)) {
2563 ret = -EEXIST;
2564 goto out;
2565 }
2566
2567 if (IS_ERR(di)) {
2568 ret = PTR_ERR(di);
2569 goto out;
2570 }
2571
2572 if (root == root->fs_info->tree_root)
2573 ret = create_subvol(root, vol_args->name, namelen);
2574 else
2575 ret = create_snapshot(root, vol_args->name, namelen);
2576 out:
2577 kfree(vol_args);
2578 return ret;
2579 }
2580
2581 static int btrfs_ioctl_defrag(struct file *file)
2582 {
2583 struct inode *inode = fdentry(file)->d_inode;
2584 struct btrfs_root *root = BTRFS_I(inode)->root;
2585
2586 switch (inode->i_mode & S_IFMT) {
2587 case S_IFDIR:
2588 mutex_lock(&root->fs_info->fs_mutex);
2589 btrfs_defrag_root(root, 0);
2590 btrfs_defrag_root(root->fs_info->extent_root, 0);
2591 mutex_unlock(&root->fs_info->fs_mutex);
2592 break;
2593 case S_IFREG:
2594 btrfs_defrag_file(file);
2595 break;
2596 }
2597
2598 return 0;
2599 }
2600
2601 long btrfs_ioctl(struct file *file, unsigned int
2602 cmd, unsigned long arg)
2603 {
2604 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2605
2606 switch (cmd) {
2607 case BTRFS_IOC_SNAP_CREATE:
2608 return btrfs_ioctl_snap_create(root, (void __user *)arg);
2609 case BTRFS_IOC_DEFRAG:
2610 return btrfs_ioctl_defrag(file);
2611 case BTRFS_IOC_RESIZE:
2612 return btrfs_ioctl_resize(root, (void __user *)arg);
2613 }
2614
2615 return -ENOTTY;
2616 }
2617
2618 /*
2619 * Called inside transaction, so use GFP_NOFS
2620 */
2621 struct inode *btrfs_alloc_inode(struct super_block *sb)
2622 {
2623 struct btrfs_inode *ei;
2624
2625 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
2626 if (!ei)
2627 return NULL;
2628 ei->last_trans = 0;
2629 ei->ordered_trans = 0;
2630 return &ei->vfs_inode;
2631 }
2632
2633 void btrfs_destroy_inode(struct inode *inode)
2634 {
2635 WARN_ON(!list_empty(&inode->i_dentry));
2636 WARN_ON(inode->i_data.nrpages);
2637
2638 btrfs_drop_extent_cache(inode, 0, (u64)-1);
2639 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
2640 }
2641
2642 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
2643 static void init_once(struct kmem_cache * cachep, void *foo)
2644 #else
2645 static void init_once(void * foo, struct kmem_cache * cachep,
2646 unsigned long flags)
2647 #endif
2648 {
2649 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
2650
2651 inode_init_once(&ei->vfs_inode);
2652 }
2653
2654 void btrfs_destroy_cachep(void)
2655 {
2656 if (btrfs_inode_cachep)
2657 kmem_cache_destroy(btrfs_inode_cachep);
2658 if (btrfs_trans_handle_cachep)
2659 kmem_cache_destroy(btrfs_trans_handle_cachep);
2660 if (btrfs_transaction_cachep)
2661 kmem_cache_destroy(btrfs_transaction_cachep);
2662 if (btrfs_bit_radix_cachep)
2663 kmem_cache_destroy(btrfs_bit_radix_cachep);
2664 if (btrfs_path_cachep)
2665 kmem_cache_destroy(btrfs_path_cachep);
2666 }
2667
2668 struct kmem_cache *btrfs_cache_create(const char *name, size_t size,
2669 unsigned long extra_flags,
2670 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
2671 void (*ctor)(struct kmem_cache *, void *)
2672 #else
2673 void (*ctor)(void *, struct kmem_cache *,
2674 unsigned long)
2675 #endif
2676 )
2677 {
2678 return kmem_cache_create(name, size, 0, (SLAB_RECLAIM_ACCOUNT |
2679 SLAB_MEM_SPREAD | extra_flags), ctor
2680 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
2681 ,NULL
2682 #endif
2683 );
2684 }
2685
2686 int btrfs_init_cachep(void)
2687 {
2688 btrfs_inode_cachep = btrfs_cache_create("btrfs_inode_cache",
2689 sizeof(struct btrfs_inode),
2690 0, init_once);
2691 if (!btrfs_inode_cachep)
2692 goto fail;
2693 btrfs_trans_handle_cachep =
2694 btrfs_cache_create("btrfs_trans_handle_cache",
2695 sizeof(struct btrfs_trans_handle),
2696 0, NULL);
2697 if (!btrfs_trans_handle_cachep)
2698 goto fail;
2699 btrfs_transaction_cachep = btrfs_cache_create("btrfs_transaction_cache",
2700 sizeof(struct btrfs_transaction),
2701 0, NULL);
2702 if (!btrfs_transaction_cachep)
2703 goto fail;
2704 btrfs_path_cachep = btrfs_cache_create("btrfs_path_cache",
2705 sizeof(struct btrfs_path),
2706 0, NULL);
2707 if (!btrfs_path_cachep)
2708 goto fail;
2709 btrfs_bit_radix_cachep = btrfs_cache_create("btrfs_radix", 256,
2710 SLAB_DESTROY_BY_RCU, NULL);
2711 if (!btrfs_bit_radix_cachep)
2712 goto fail;
2713 return 0;
2714 fail:
2715 btrfs_destroy_cachep();
2716 return -ENOMEM;
2717 }
2718
2719 static int btrfs_getattr(struct vfsmount *mnt,
2720 struct dentry *dentry, struct kstat *stat)
2721 {
2722 struct inode *inode = dentry->d_inode;
2723 generic_fillattr(inode, stat);
2724 stat->blksize = PAGE_CACHE_SIZE;
2725 return 0;
2726 }
2727
2728 static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
2729 struct inode * new_dir,struct dentry *new_dentry)
2730 {
2731 struct btrfs_trans_handle *trans;
2732 struct btrfs_root *root = BTRFS_I(old_dir)->root;
2733 struct inode *new_inode = new_dentry->d_inode;
2734 struct inode *old_inode = old_dentry->d_inode;
2735 struct timespec ctime = CURRENT_TIME;
2736 struct btrfs_path *path;
2737 int ret;
2738
2739 if (S_ISDIR(old_inode->i_mode) && new_inode &&
2740 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
2741 return -ENOTEMPTY;
2742 }
2743
2744 mutex_lock(&root->fs_info->fs_mutex);
2745 ret = btrfs_check_free_space(root, 1, 0);
2746 if (ret)
2747 goto out_unlock;
2748
2749 trans = btrfs_start_transaction(root, 1);
2750
2751 btrfs_set_trans_block_group(trans, new_dir);
2752 path = btrfs_alloc_path();
2753 if (!path) {
2754 ret = -ENOMEM;
2755 goto out_fail;
2756 }
2757
2758 old_dentry->d_inode->i_nlink++;
2759 old_dir->i_ctime = old_dir->i_mtime = ctime;
2760 new_dir->i_ctime = new_dir->i_mtime = ctime;
2761 old_inode->i_ctime = ctime;
2762
2763 ret = btrfs_unlink_trans(trans, root, old_dir, old_dentry);
2764 if (ret)
2765 goto out_fail;
2766
2767 if (new_inode) {
2768 new_inode->i_ctime = CURRENT_TIME;
2769 ret = btrfs_unlink_trans(trans, root, new_dir, new_dentry);
2770 if (ret)
2771 goto out_fail;
2772 }
2773 ret = btrfs_add_link(trans, new_dentry, old_inode);
2774 if (ret)
2775 goto out_fail;
2776
2777 out_fail:
2778 btrfs_free_path(path);
2779 btrfs_end_transaction(trans, root);
2780 out_unlock:
2781 mutex_unlock(&root->fs_info->fs_mutex);
2782 return ret;
2783 }
2784
2785 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
2786 const char *symname)
2787 {
2788 struct btrfs_trans_handle *trans;
2789 struct btrfs_root *root = BTRFS_I(dir)->root;
2790 struct btrfs_path *path;
2791 struct btrfs_key key;
2792 struct inode *inode = NULL;
2793 int err;
2794 int drop_inode = 0;
2795 u64 objectid;
2796 int name_len;
2797 int datasize;
2798 unsigned long ptr;
2799 struct btrfs_file_extent_item *ei;
2800 struct extent_buffer *leaf;
2801 unsigned long nr = 0;
2802
2803 name_len = strlen(symname) + 1;
2804 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
2805 return -ENAMETOOLONG;
2806
2807 mutex_lock(&root->fs_info->fs_mutex);
2808 err = btrfs_check_free_space(root, 1, 0);
2809 if (err)
2810 goto out_fail;
2811
2812 trans = btrfs_start_transaction(root, 1);
2813 btrfs_set_trans_block_group(trans, dir);
2814
2815 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2816 if (err) {
2817 err = -ENOSPC;
2818 goto out_unlock;
2819 }
2820
2821 inode = btrfs_new_inode(trans, root, objectid,
2822 BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO);
2823 err = PTR_ERR(inode);
2824 if (IS_ERR(inode))
2825 goto out_unlock;
2826
2827 btrfs_set_trans_block_group(trans, inode);
2828 err = btrfs_add_nondir(trans, dentry, inode);
2829 if (err)
2830 drop_inode = 1;
2831 else {
2832 inode->i_mapping->a_ops = &btrfs_aops;
2833 inode->i_fop = &btrfs_file_operations;
2834 inode->i_op = &btrfs_file_inode_operations;
2835 extent_map_tree_init(&BTRFS_I(inode)->extent_tree,
2836 inode->i_mapping, GFP_NOFS);
2837 BTRFS_I(inode)->extent_tree.ops = &btrfs_extent_map_ops;
2838 }
2839 dir->i_sb->s_dirt = 1;
2840 btrfs_update_inode_block_group(trans, inode);
2841 btrfs_update_inode_block_group(trans, dir);
2842 if (drop_inode)
2843 goto out_unlock;
2844
2845 path = btrfs_alloc_path();
2846 BUG_ON(!path);
2847 key.objectid = inode->i_ino;
2848 key.offset = 0;
2849 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
2850 datasize = btrfs_file_extent_calc_inline_size(name_len);
2851 err = btrfs_insert_empty_item(trans, root, path, &key,
2852 datasize);
2853 if (err) {
2854 drop_inode = 1;
2855 goto out_unlock;
2856 }
2857 leaf = path->nodes[0];
2858 ei = btrfs_item_ptr(leaf, path->slots[0],
2859 struct btrfs_file_extent_item);
2860 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
2861 btrfs_set_file_extent_type(leaf, ei,
2862 BTRFS_FILE_EXTENT_INLINE);
2863 ptr = btrfs_file_extent_inline_start(ei);
2864 write_extent_buffer(leaf, symname, ptr, name_len);
2865 btrfs_mark_buffer_dirty(leaf);
2866 btrfs_free_path(path);
2867
2868 inode->i_op = &btrfs_symlink_inode_operations;
2869 inode->i_mapping->a_ops = &btrfs_symlink_aops;
2870 inode->i_size = name_len - 1;
2871 err = btrfs_update_inode(trans, root, inode);
2872 if (err)
2873 drop_inode = 1;
2874
2875 out_unlock:
2876 nr = trans->blocks_used;
2877 btrfs_end_transaction(trans, root);
2878 out_fail:
2879 mutex_unlock(&root->fs_info->fs_mutex);
2880 if (drop_inode) {
2881 inode_dec_link_count(inode);
2882 iput(inode);
2883 }
2884 btrfs_btree_balance_dirty(root, nr);
2885 btrfs_throttle(root);
2886 return err;
2887 }
2888 static int btrfs_permission(struct inode *inode, int mask,
2889 struct nameidata *nd)
2890 {
2891 if (btrfs_test_flag(inode, READONLY) && (mask & MAY_WRITE))
2892 return -EACCES;
2893 return generic_permission(inode, mask, NULL);
2894 }
2895
2896 static struct inode_operations btrfs_dir_inode_operations = {
2897 .lookup = btrfs_lookup,
2898 .create = btrfs_create,
2899 .unlink = btrfs_unlink,
2900 .link = btrfs_link,
2901 .mkdir = btrfs_mkdir,
2902 .rmdir = btrfs_rmdir,
2903 .rename = btrfs_rename,
2904 .symlink = btrfs_symlink,
2905 .setattr = btrfs_setattr,
2906 .mknod = btrfs_mknod,
2907 .setxattr = generic_setxattr,
2908 .getxattr = generic_getxattr,
2909 .listxattr = btrfs_listxattr,
2910 .removexattr = generic_removexattr,
2911 .permission = btrfs_permission,
2912 };
2913 static struct inode_operations btrfs_dir_ro_inode_operations = {
2914 .lookup = btrfs_lookup,
2915 .permission = btrfs_permission,
2916 };
2917 static struct file_operations btrfs_dir_file_operations = {
2918 .llseek = generic_file_llseek,
2919 .read = generic_read_dir,
2920 .readdir = btrfs_readdir,
2921 .unlocked_ioctl = btrfs_ioctl,
2922 #ifdef CONFIG_COMPAT
2923 .compat_ioctl = btrfs_ioctl,
2924 #endif
2925 };
2926
2927 static struct extent_map_ops btrfs_extent_map_ops = {
2928 .fill_delalloc = run_delalloc_range,
2929 .writepage_io_hook = btrfs_writepage_io_hook,
2930 .readpage_io_hook = btrfs_readpage_io_hook,
2931 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
2932 };
2933
2934 static struct address_space_operations btrfs_aops = {
2935 .readpage = btrfs_readpage,
2936 .writepage = btrfs_writepage,
2937 .writepages = btrfs_writepages,
2938 .readpages = btrfs_readpages,
2939 .sync_page = block_sync_page,
2940 .bmap = btrfs_bmap,
2941 .invalidatepage = btrfs_invalidatepage,
2942 .releasepage = btrfs_releasepage,
2943 .set_page_dirty = __set_page_dirty_nobuffers,
2944 };
2945
2946 static struct address_space_operations btrfs_symlink_aops = {
2947 .readpage = btrfs_readpage,
2948 .writepage = btrfs_writepage,
2949 .invalidatepage = btrfs_invalidatepage,
2950 .releasepage = btrfs_releasepage,
2951 };
2952
2953 static struct inode_operations btrfs_file_inode_operations = {
2954 .truncate = btrfs_truncate,
2955 .getattr = btrfs_getattr,
2956 .setattr = btrfs_setattr,
2957 .setxattr = generic_setxattr,
2958 .getxattr = generic_getxattr,
2959 .listxattr = btrfs_listxattr,
2960 .removexattr = generic_removexattr,
2961 .permission = btrfs_permission,
2962 };
2963 static struct inode_operations btrfs_special_inode_operations = {
2964 .getattr = btrfs_getattr,
2965 .setattr = btrfs_setattr,
2966 .permission = btrfs_permission,
2967 };
2968 static struct inode_operations btrfs_symlink_inode_operations = {
2969 .readlink = generic_readlink,
2970 .follow_link = page_follow_link_light,
2971 .put_link = page_put_link,
2972 .permission = btrfs_permission,
2973 };
Linux kernel - Deliverables
This page took 0.131847 seconds and 6 git commands to generate.