projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Btrfs: During deletes and truncate, remove many items at once from the tree
[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_io_ops btrfs_extent_io_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 u64 orig_start = start;
108 u64 orig_num_bytes;
109 struct btrfs_key ins;
110 int ret;
111
112 trans = btrfs_start_transaction(root, 1);
113 BUG_ON(!trans);
114 btrfs_set_trans_block_group(trans, inode);
115
116 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
117 num_bytes = max(blocksize, num_bytes);
118 ret = btrfs_drop_extents(trans, root, inode,
119 start, start + num_bytes, start, &alloc_hint);
120 orig_num_bytes = num_bytes;
121
122 if (alloc_hint == EXTENT_MAP_INLINE)
123 goto out;
124
125 while(num_bytes > 0) {
126 cur_alloc_size = min(num_bytes, root->fs_info->max_extent);
127 ret = btrfs_alloc_extent(trans, root, cur_alloc_size,
128 root->root_key.objectid,
129 trans->transid,
130 inode->i_ino, start, 0,
131 alloc_hint, (u64)-1, &ins, 1);
132 if (ret) {
133 WARN_ON(1);
134 goto out;
135 }
136 ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
137 start, ins.objectid, ins.offset,
138 ins.offset);
139 btrfs_check_file(root, inode);
140 num_bytes -= cur_alloc_size;
141 alloc_hint = ins.objectid + ins.offset;
142 start += cur_alloc_size;
143 }
144 btrfs_drop_extent_cache(inode, orig_start,
145 orig_start + orig_num_bytes - 1);
146 btrfs_add_ordered_inode(inode);
147 out:
148 btrfs_end_transaction(trans, root);
149 return ret;
150 }
151
152 static int run_delalloc_nocow(struct inode *inode, u64 start, u64 end)
153 {
154 u64 extent_start;
155 u64 extent_end;
156 u64 bytenr;
157 u64 cow_end;
158 u64 loops = 0;
159 u64 total_fs_bytes;
160 struct btrfs_root *root = BTRFS_I(inode)->root;
161 struct extent_buffer *leaf;
162 int found_type;
163 struct btrfs_path *path;
164 struct btrfs_file_extent_item *item;
165 int ret;
166 int err;
167 struct btrfs_key found_key;
168
169 total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
170 path = btrfs_alloc_path();
171 BUG_ON(!path);
172 again:
173 ret = btrfs_lookup_file_extent(NULL, root, path,
174 inode->i_ino, start, 0);
175 if (ret < 0) {
176 btrfs_free_path(path);
177 return ret;
178 }
179
180 cow_end = end;
181 if (ret != 0) {
182 if (path->slots[0] == 0)
183 goto not_found;
184 path->slots[0]--;
185 }
186
187 leaf = path->nodes[0];
188 item = btrfs_item_ptr(leaf, path->slots[0],
189 struct btrfs_file_extent_item);
190
191 /* are we inside the extent that was found? */
192 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
193 found_type = btrfs_key_type(&found_key);
194 if (found_key.objectid != inode->i_ino ||
195 found_type != BTRFS_EXTENT_DATA_KEY) {
196 goto not_found;
197 }
198
199 found_type = btrfs_file_extent_type(leaf, item);
200 extent_start = found_key.offset;
201 if (found_type == BTRFS_FILE_EXTENT_REG) {
202 u64 extent_num_bytes;
203
204 extent_num_bytes = btrfs_file_extent_num_bytes(leaf, item);
205 extent_end = extent_start + extent_num_bytes;
206 err = 0;
207
208 if (loops && start != extent_start)
209 goto not_found;
210
211 if (start < extent_start || start >= extent_end)
212 goto not_found;
213
214 cow_end = min(end, extent_end - 1);
215 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
216 if (bytenr == 0)
217 goto not_found;
218
219 /*
220 * we may be called by the resizer, make sure we're inside
221 * the limits of the FS
222 */
223 if (bytenr + extent_num_bytes > total_fs_bytes)
224 goto not_found;
225
226 if (btrfs_count_snapshots_in_path(root, path, bytenr) != 1) {
227 goto not_found;
228 }
229
230 start = extent_end;
231 } else {
232 goto not_found;
233 }
234 loop:
235 if (start > end) {
236 btrfs_free_path(path);
237 return 0;
238 }
239 btrfs_release_path(root, path);
240 loops++;
241 goto again;
242
243 not_found:
244 cow_file_range(inode, start, cow_end);
245 start = cow_end + 1;
246 goto loop;
247 }
248
249 static int run_delalloc_range(struct inode *inode, u64 start, u64 end)
250 {
251 struct btrfs_root *root = BTRFS_I(inode)->root;
252 u64 num_bytes;
253 int ret;
254 mutex_lock(&root->fs_info->fs_mutex);
255 if (btrfs_test_opt(root, NODATACOW) ||
256 btrfs_test_flag(inode, NODATACOW))
257 ret = run_delalloc_nocow(inode, start, end);
258 else
259 ret = cow_file_range(inode, start, end);
260
261 spin_lock(&root->fs_info->delalloc_lock);
262 num_bytes = end + 1 - start;
263 if (root->fs_info->delalloc_bytes < num_bytes) {
264 printk("delalloc accounting error total %llu sub %llu\n",
265 root->fs_info->delalloc_bytes, num_bytes);
266 } else {
267 root->fs_info->delalloc_bytes -= num_bytes;
268 }
269 spin_unlock(&root->fs_info->delalloc_lock);
270
271 mutex_unlock(&root->fs_info->fs_mutex);
272 return ret;
273 }
274
275 int btrfs_writepage_io_hook(struct page *page, u64 start, u64 end)
276 {
277 struct inode *inode = page->mapping->host;
278 struct btrfs_root *root = BTRFS_I(inode)->root;
279 struct btrfs_trans_handle *trans;
280 char *kaddr;
281 int ret = 0;
282 u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
283 size_t offset = start - page_start;
284 if (btrfs_test_opt(root, NODATASUM) ||
285 btrfs_test_flag(inode, NODATASUM))
286 return 0;
287 mutex_lock(&root->fs_info->fs_mutex);
288 trans = btrfs_start_transaction(root, 1);
289 btrfs_set_trans_block_group(trans, inode);
290 kaddr = kmap(page);
291 btrfs_csum_file_block(trans, root, inode, inode->i_ino,
292 start, kaddr + offset, end - start + 1);
293 kunmap(page);
294 ret = btrfs_end_transaction(trans, root);
295 BUG_ON(ret);
296 mutex_unlock(&root->fs_info->fs_mutex);
297 return ret;
298 }
299
300 int btrfs_readpage_io_hook(struct page *page, u64 start, u64 end)
301 {
302 int ret = 0;
303 struct inode *inode = page->mapping->host;
304 struct btrfs_root *root = BTRFS_I(inode)->root;
305 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
306 struct btrfs_csum_item *item;
307 struct btrfs_path *path = NULL;
308 u32 csum;
309 if (btrfs_test_opt(root, NODATASUM) ||
310 btrfs_test_flag(inode, NODATASUM))
311 return 0;
312 mutex_lock(&root->fs_info->fs_mutex);
313 path = btrfs_alloc_path();
314 item = btrfs_lookup_csum(NULL, root, path, inode->i_ino, start, 0);
315 if (IS_ERR(item)) {
316 ret = PTR_ERR(item);
317 /* a csum that isn't present is a preallocated region. */
318 if (ret == -ENOENT || ret == -EFBIG)
319 ret = 0;
320 csum = 0;
321 printk("no csum found for inode %lu start %Lu\n", inode->i_ino, start);
322 goto out;
323 }
324 read_extent_buffer(path->nodes[0], &csum, (unsigned long)item,
325 BTRFS_CRC32_SIZE);
326 set_state_private(io_tree, start, csum);
327 out:
328 if (path)
329 btrfs_free_path(path);
330 mutex_unlock(&root->fs_info->fs_mutex);
331 return ret;
332 }
333
334 int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
335 struct extent_state *state)
336 {
337 size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
338 struct inode *inode = page->mapping->host;
339 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
340 char *kaddr;
341 u64 private = ~(u32)0;
342 int ret;
343 struct btrfs_root *root = BTRFS_I(inode)->root;
344 u32 csum = ~(u32)0;
345 unsigned long flags;
346
347 if (btrfs_test_opt(root, NODATASUM) ||
348 btrfs_test_flag(inode, NODATASUM))
349 return 0;
350
351 if (state->start == start) {
352 private = state->private;
353 ret = 0;
354 } else {
355 ret = get_state_private(io_tree, start, &private);
356 }
357 local_irq_save(flags);
358 kaddr = kmap_atomic(page, KM_IRQ0);
359 if (ret) {
360 goto zeroit;
361 }
362 csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1);
363 btrfs_csum_final(csum, (char *)&csum);
364 if (csum != private) {
365 goto zeroit;
366 }
367 kunmap_atomic(kaddr, KM_IRQ0);
368 local_irq_restore(flags);
369 return 0;
370
371 zeroit:
372 printk("btrfs csum failed ino %lu off %llu csum %u private %Lu\n",
373 page->mapping->host->i_ino, (unsigned long long)start, csum,
374 private);
375 memset(kaddr + offset, 1, end - start + 1);
376 flush_dcache_page(page);
377 kunmap_atomic(kaddr, KM_IRQ0);
378 local_irq_restore(flags);
379 return 0;
380 }
381
382 void btrfs_read_locked_inode(struct inode *inode)
383 {
384 struct btrfs_path *path;
385 struct extent_buffer *leaf;
386 struct btrfs_inode_item *inode_item;
387 struct btrfs_inode_timespec *tspec;
388 struct btrfs_root *root = BTRFS_I(inode)->root;
389 struct btrfs_key location;
390 u64 alloc_group_block;
391 u32 rdev;
392 int ret;
393
394 path = btrfs_alloc_path();
395 BUG_ON(!path);
396 mutex_lock(&root->fs_info->fs_mutex);
397 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
398
399 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
400 if (ret)
401 goto make_bad;
402
403 leaf = path->nodes[0];
404 inode_item = btrfs_item_ptr(leaf, path->slots[0],
405 struct btrfs_inode_item);
406
407 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
408 inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
409 inode->i_uid = btrfs_inode_uid(leaf, inode_item);
410 inode->i_gid = btrfs_inode_gid(leaf, inode_item);
411 inode->i_size = btrfs_inode_size(leaf, inode_item);
412
413 tspec = btrfs_inode_atime(inode_item);
414 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
415 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
416
417 tspec = btrfs_inode_mtime(inode_item);
418 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
419 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
420
421 tspec = btrfs_inode_ctime(inode_item);
422 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
423 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
424
425 inode->i_blocks = btrfs_inode_nblocks(leaf, inode_item);
426 inode->i_generation = btrfs_inode_generation(leaf, inode_item);
427 inode->i_rdev = 0;
428 rdev = btrfs_inode_rdev(leaf, inode_item);
429
430 alloc_group_block = btrfs_inode_block_group(leaf, inode_item);
431 BTRFS_I(inode)->block_group = btrfs_lookup_block_group(root->fs_info,
432 alloc_group_block);
433 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
434 if (!BTRFS_I(inode)->block_group) {
435 BTRFS_I(inode)->block_group = btrfs_find_block_group(root,
436 NULL, 0, 0, 0);
437 }
438 btrfs_free_path(path);
439 inode_item = NULL;
440
441 mutex_unlock(&root->fs_info->fs_mutex);
442
443 switch (inode->i_mode & S_IFMT) {
444 case S_IFREG:
445 inode->i_mapping->a_ops = &btrfs_aops;
446 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
447 inode->i_fop = &btrfs_file_operations;
448 inode->i_op = &btrfs_file_inode_operations;
449 break;
450 case S_IFDIR:
451 inode->i_fop = &btrfs_dir_file_operations;
452 if (root == root->fs_info->tree_root)
453 inode->i_op = &btrfs_dir_ro_inode_operations;
454 else
455 inode->i_op = &btrfs_dir_inode_operations;
456 break;
457 case S_IFLNK:
458 inode->i_op = &btrfs_symlink_inode_operations;
459 inode->i_mapping->a_ops = &btrfs_symlink_aops;
460 break;
461 default:
462 init_special_inode(inode, inode->i_mode, rdev);
463 break;
464 }
465 return;
466
467 make_bad:
468 btrfs_release_path(root, path);
469 btrfs_free_path(path);
470 mutex_unlock(&root->fs_info->fs_mutex);
471 make_bad_inode(inode);
472 }
473
474 static void fill_inode_item(struct extent_buffer *leaf,
475 struct btrfs_inode_item *item,
476 struct inode *inode)
477 {
478 btrfs_set_inode_uid(leaf, item, inode->i_uid);
479 btrfs_set_inode_gid(leaf, item, inode->i_gid);
480 btrfs_set_inode_size(leaf, item, inode->i_size);
481 btrfs_set_inode_mode(leaf, item, inode->i_mode);
482 btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
483
484 btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
485 inode->i_atime.tv_sec);
486 btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
487 inode->i_atime.tv_nsec);
488
489 btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
490 inode->i_mtime.tv_sec);
491 btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
492 inode->i_mtime.tv_nsec);
493
494 btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
495 inode->i_ctime.tv_sec);
496 btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
497 inode->i_ctime.tv_nsec);
498
499 btrfs_set_inode_nblocks(leaf, item, inode->i_blocks);
500 btrfs_set_inode_generation(leaf, item, inode->i_generation);
501 btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
502 btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
503 btrfs_set_inode_block_group(leaf, item,
504 BTRFS_I(inode)->block_group->key.objectid);
505 }
506
507 int btrfs_update_inode(struct btrfs_trans_handle *trans,
508 struct btrfs_root *root,
509 struct inode *inode)
510 {
511 struct btrfs_inode_item *inode_item;
512 struct btrfs_path *path;
513 struct extent_buffer *leaf;
514 int ret;
515
516 path = btrfs_alloc_path();
517 BUG_ON(!path);
518 ret = btrfs_lookup_inode(trans, root, path,
519 &BTRFS_I(inode)->location, 1);
520 if (ret) {
521 if (ret > 0)
522 ret = -ENOENT;
523 goto failed;
524 }
525
526 leaf = path->nodes[0];
527 inode_item = btrfs_item_ptr(leaf, path->slots[0],
528 struct btrfs_inode_item);
529
530 fill_inode_item(leaf, inode_item, inode);
531 btrfs_mark_buffer_dirty(leaf);
532 btrfs_set_inode_last_trans(trans, inode);
533 ret = 0;
534 failed:
535 btrfs_release_path(root, path);
536 btrfs_free_path(path);
537 return ret;
538 }
539
540
541 static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
542 struct btrfs_root *root,
543 struct inode *dir,
544 struct dentry *dentry)
545 {
546 struct btrfs_path *path;
547 const char *name = dentry->d_name.name;
548 int name_len = dentry->d_name.len;
549 int ret = 0;
550 struct extent_buffer *leaf;
551 struct btrfs_dir_item *di;
552 struct btrfs_key key;
553
554 path = btrfs_alloc_path();
555 if (!path) {
556 ret = -ENOMEM;
557 goto err;
558 }
559
560 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
561 name, name_len, -1);
562 if (IS_ERR(di)) {
563 ret = PTR_ERR(di);
564 goto err;
565 }
566 if (!di) {
567 ret = -ENOENT;
568 goto err;
569 }
570 leaf = path->nodes[0];
571 btrfs_dir_item_key_to_cpu(leaf, di, &key);
572 ret = btrfs_delete_one_dir_name(trans, root, path, di);
573 if (ret)
574 goto err;
575 btrfs_release_path(root, path);
576
577 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
578 key.objectid, name, name_len, -1);
579 if (IS_ERR(di)) {
580 ret = PTR_ERR(di);
581 goto err;
582 }
583 if (!di) {
584 ret = -ENOENT;
585 goto err;
586 }
587 ret = btrfs_delete_one_dir_name(trans, root, path, di);
588
589 dentry->d_inode->i_ctime = dir->i_ctime;
590 ret = btrfs_del_inode_ref(trans, root, name, name_len,
591 dentry->d_inode->i_ino,
592 dentry->d_parent->d_inode->i_ino);
593 if (ret) {
594 printk("failed to delete reference to %.*s, "
595 "inode %lu parent %lu\n", name_len, name,
596 dentry->d_inode->i_ino,
597 dentry->d_parent->d_inode->i_ino);
598 }
599 err:
600 btrfs_free_path(path);
601 if (!ret) {
602 dir->i_size -= name_len * 2;
603 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
604 btrfs_update_inode(trans, root, dir);
605 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
606 dentry->d_inode->i_nlink--;
607 #else
608 drop_nlink(dentry->d_inode);
609 #endif
610 ret = btrfs_update_inode(trans, root, dentry->d_inode);
611 dir->i_sb->s_dirt = 1;
612 }
613 return ret;
614 }
615
616 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
617 {
618 struct btrfs_root *root;
619 struct btrfs_trans_handle *trans;
620 struct inode *inode = dentry->d_inode;
621 int ret;
622 unsigned long nr = 0;
623
624 root = BTRFS_I(dir)->root;
625 mutex_lock(&root->fs_info->fs_mutex);
626
627 ret = btrfs_check_free_space(root, 1, 1);
628 if (ret)
629 goto fail;
630
631 trans = btrfs_start_transaction(root, 1);
632
633 btrfs_set_trans_block_group(trans, dir);
634 ret = btrfs_unlink_trans(trans, root, dir, dentry);
635 nr = trans->blocks_used;
636
637 if (inode->i_nlink == 0) {
638 int found;
639 /* if the inode isn't linked anywhere,
640 * we don't need to worry about
641 * data=ordered
642 */
643 found = btrfs_del_ordered_inode(inode);
644 if (found == 1) {
645 atomic_dec(&inode->i_count);
646 }
647 }
648
649 btrfs_end_transaction(trans, root);
650 fail:
651 mutex_unlock(&root->fs_info->fs_mutex);
652 btrfs_btree_balance_dirty(root, nr);
653 btrfs_throttle(root);
654 return ret;
655 }
656
657 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
658 {
659 struct inode *inode = dentry->d_inode;
660 int err = 0;
661 int ret;
662 struct btrfs_root *root = BTRFS_I(dir)->root;
663 struct btrfs_trans_handle *trans;
664 unsigned long nr = 0;
665
666 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
667 return -ENOTEMPTY;
668
669 mutex_lock(&root->fs_info->fs_mutex);
670 ret = btrfs_check_free_space(root, 1, 1);
671 if (ret)
672 goto fail;
673
674 trans = btrfs_start_transaction(root, 1);
675 btrfs_set_trans_block_group(trans, dir);
676
677 /* now the directory is empty */
678 err = btrfs_unlink_trans(trans, root, dir, dentry);
679 if (!err) {
680 inode->i_size = 0;
681 }
682
683 nr = trans->blocks_used;
684 ret = btrfs_end_transaction(trans, root);
685 fail:
686 mutex_unlock(&root->fs_info->fs_mutex);
687 btrfs_btree_balance_dirty(root, nr);
688 btrfs_throttle(root);
689
690 if (ret && !err)
691 err = ret;
692 return err;
693 }
694
695 /*
696 * this can truncate away extent items, csum items and directory items.
697 * It starts at a high offset and removes keys until it can't find
698 * any higher than i_size.
699 *
700 * csum items that cross the new i_size are truncated to the new size
701 * as well.
702 */
703 static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
704 struct btrfs_root *root,
705 struct inode *inode,
706 u32 min_type)
707 {
708 int ret;
709 struct btrfs_path *path;
710 struct btrfs_key key;
711 struct btrfs_key found_key;
712 u32 found_type;
713 struct extent_buffer *leaf;
714 struct btrfs_file_extent_item *fi;
715 u64 extent_start = 0;
716 u64 extent_num_bytes = 0;
717 u64 item_end = 0;
718 u64 root_gen = 0;
719 u64 root_owner = 0;
720 int found_extent;
721 int del_item;
722 int pending_del_nr = 0;
723 int pending_del_slot = 0;
724 int extent_type = -1;
725
726 btrfs_drop_extent_cache(inode, inode->i_size, (u64)-1);
727 path = btrfs_alloc_path();
728 path->reada = -1;
729 BUG_ON(!path);
730
731 /* FIXME, add redo link to tree so we don't leak on crash */
732 key.objectid = inode->i_ino;
733 key.offset = (u64)-1;
734 key.type = (u8)-1;
735
736 btrfs_init_path(path);
737 search_again:
738 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
739 if (ret < 0) {
740 goto error;
741 }
742 if (ret > 0) {
743 BUG_ON(path->slots[0] == 0);
744 path->slots[0]--;
745 }
746
747 while(1) {
748 fi = NULL;
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 < min_type)
757 break;
758
759 item_end = found_key.offset;
760 if (found_type == BTRFS_EXTENT_DATA_KEY) {
761 fi = btrfs_item_ptr(leaf, path->slots[0],
762 struct btrfs_file_extent_item);
763 extent_type = btrfs_file_extent_type(leaf, fi);
764 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
765 item_end +=
766 btrfs_file_extent_num_bytes(leaf, fi);
767 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
768 struct btrfs_item *item = btrfs_item_nr(leaf,
769 path->slots[0]);
770 item_end += btrfs_file_extent_inline_len(leaf,
771 item);
772 }
773 item_end--;
774 }
775 if (found_type == BTRFS_CSUM_ITEM_KEY) {
776 ret = btrfs_csum_truncate(trans, root, path,
777 inode->i_size);
778 BUG_ON(ret);
779 }
780 if (item_end < inode->i_size) {
781 if (found_type == BTRFS_DIR_ITEM_KEY) {
782 found_type = BTRFS_INODE_ITEM_KEY;
783 } else if (found_type == BTRFS_EXTENT_ITEM_KEY) {
784 found_type = BTRFS_CSUM_ITEM_KEY;
785 } else if (found_type == BTRFS_EXTENT_DATA_KEY) {
786 found_type = BTRFS_XATTR_ITEM_KEY;
787 } else if (found_type == BTRFS_XATTR_ITEM_KEY) {
788 found_type = BTRFS_INODE_REF_KEY;
789 } else if (found_type) {
790 found_type--;
791 } else {
792 break;
793 }
794 btrfs_set_key_type(&key, found_type);
795 goto next;
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 if (!pending_del_nr) {
848 /* no pending yet, add ourselves */
849 pending_del_slot = path->slots[0];
850 pending_del_nr = 1;
851 } else if (pending_del_nr &&
852 path->slots[0] + 1 == pending_del_slot) {
853 /* hop on the pending chunk */
854 pending_del_nr++;
855 pending_del_slot = path->slots[0];
856 } else {
857 printk("bad pending slot %d pending_del_nr %d pending_del_slot %d\n", path->slots[0], pending_del_nr, pending_del_slot);
858 }
859 } else {
860 break;
861 }
862 if (found_extent) {
863 ret = btrfs_free_extent(trans, root, extent_start,
864 extent_num_bytes,
865 root_owner,
866 root_gen, inode->i_ino,
867 found_key.offset, 0);
868 BUG_ON(ret);
869 }
870 next:
871 if (path->slots[0] == 0) {
872 if (pending_del_nr)
873 goto del_pending;
874 btrfs_release_path(root, path);
875 goto search_again;
876 }
877
878 path->slots[0]--;
879 if (pending_del_nr &&
880 path->slots[0] + 1 != pending_del_slot) {
881 struct btrfs_key debug;
882 del_pending:
883 btrfs_item_key_to_cpu(path->nodes[0], &debug,
884 pending_del_slot);
885 ret = btrfs_del_items(trans, root, path,
886 pending_del_slot,
887 pending_del_nr);
888 BUG_ON(ret);
889 pending_del_nr = 0;
890 btrfs_release_path(root, path);
891 goto search_again;
892 }
893 }
894 ret = 0;
895 error:
896 if (pending_del_nr) {
897 ret = btrfs_del_items(trans, root, path, pending_del_slot,
898 pending_del_nr);
899 }
900 btrfs_release_path(root, path);
901 btrfs_free_path(path);
902 inode->i_sb->s_dirt = 1;
903 return ret;
904 }
905
906 static int btrfs_cow_one_page(struct inode *inode, struct page *page,
907 size_t zero_start)
908 {
909 char *kaddr;
910 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
911 struct btrfs_root *root = BTRFS_I(inode)->root;
912 u64 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
913 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
914 u64 existing_delalloc;
915 u64 delalloc_start;
916 int ret = 0;
917
918 WARN_ON(!PageLocked(page));
919 set_page_extent_mapped(page);
920
921 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
922 delalloc_start = page_start;
923 existing_delalloc = count_range_bits(&BTRFS_I(inode)->io_tree,
924 &delalloc_start, page_end,
925 PAGE_CACHE_SIZE, EXTENT_DELALLOC);
926 set_extent_delalloc(&BTRFS_I(inode)->io_tree, page_start,
927 page_end, GFP_NOFS);
928
929 spin_lock(&root->fs_info->delalloc_lock);
930 root->fs_info->delalloc_bytes += PAGE_CACHE_SIZE - existing_delalloc;
931 spin_unlock(&root->fs_info->delalloc_lock);
932
933 if (zero_start != PAGE_CACHE_SIZE) {
934 kaddr = kmap(page);
935 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
936 flush_dcache_page(page);
937 kunmap(page);
938 }
939 set_page_dirty(page);
940 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
941
942 return ret;
943 }
944
945 /*
946 * taken from block_truncate_page, but does cow as it zeros out
947 * any bytes left in the last page in the file.
948 */
949 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
950 {
951 struct inode *inode = mapping->host;
952 struct btrfs_root *root = BTRFS_I(inode)->root;
953 u32 blocksize = root->sectorsize;
954 pgoff_t index = from >> PAGE_CACHE_SHIFT;
955 unsigned offset = from & (PAGE_CACHE_SIZE-1);
956 struct page *page;
957 int ret = 0;
958 u64 page_start;
959
960 if ((offset & (blocksize - 1)) == 0)
961 goto out;
962
963 ret = -ENOMEM;
964 page = grab_cache_page(mapping, index);
965 if (!page)
966 goto out;
967 if (!PageUptodate(page)) {
968 ret = btrfs_readpage(NULL, page);
969 lock_page(page);
970 if (!PageUptodate(page)) {
971 ret = -EIO;
972 goto out;
973 }
974 }
975 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
976
977 ret = btrfs_cow_one_page(inode, page, offset);
978
979 unlock_page(page);
980 page_cache_release(page);
981 out:
982 return ret;
983 }
984
985 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
986 {
987 struct inode *inode = dentry->d_inode;
988 int err;
989
990 err = inode_change_ok(inode, attr);
991 if (err)
992 return err;
993
994 if (S_ISREG(inode->i_mode) &&
995 attr->ia_valid & ATTR_SIZE && attr->ia_size > inode->i_size) {
996 struct btrfs_trans_handle *trans;
997 struct btrfs_root *root = BTRFS_I(inode)->root;
998 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
999
1000 u64 mask = root->sectorsize - 1;
1001 u64 pos = (inode->i_size + mask) & ~mask;
1002 u64 block_end = attr->ia_size | mask;
1003 u64 hole_start;
1004 u64 hole_size;
1005 u64 alloc_hint = 0;
1006
1007 if (attr->ia_size <= pos)
1008 goto out;
1009
1010 if (pos != inode->i_size)
1011 hole_start = pos + root->sectorsize;
1012 else
1013 hole_start = pos;
1014
1015 mutex_lock(&root->fs_info->fs_mutex);
1016 err = btrfs_check_free_space(root, 1, 0);
1017 mutex_unlock(&root->fs_info->fs_mutex);
1018 if (err)
1019 goto fail;
1020
1021 btrfs_truncate_page(inode->i_mapping, inode->i_size);
1022
1023 lock_extent(io_tree, pos, block_end, GFP_NOFS);
1024 hole_size = block_end - hole_start;
1025
1026 mutex_lock(&root->fs_info->fs_mutex);
1027 trans = btrfs_start_transaction(root, 1);
1028 btrfs_set_trans_block_group(trans, inode);
1029 err = btrfs_drop_extents(trans, root, inode,
1030 pos, block_end, pos,
1031 &alloc_hint);
1032
1033 if (alloc_hint != EXTENT_MAP_INLINE) {
1034 err = btrfs_insert_file_extent(trans, root,
1035 inode->i_ino,
1036 hole_start, 0, 0,
1037 hole_size);
1038 btrfs_drop_extent_cache(inode, hole_start,
1039 hole_size - 1);
1040 btrfs_check_file(root, inode);
1041 }
1042 btrfs_end_transaction(trans, root);
1043 mutex_unlock(&root->fs_info->fs_mutex);
1044 unlock_extent(io_tree, pos, block_end, GFP_NOFS);
1045 if (err)
1046 return err;
1047 }
1048 out:
1049 err = inode_setattr(inode, attr);
1050 fail:
1051 return err;
1052 }
1053
1054 void btrfs_put_inode(struct inode *inode)
1055 {
1056 int ret;
1057
1058 if (!BTRFS_I(inode)->ordered_trans) {
1059 return;
1060 }
1061
1062 if (mapping_tagged(inode->i_mapping, PAGECACHE_TAG_DIRTY) ||
1063 mapping_tagged(inode->i_mapping, PAGECACHE_TAG_WRITEBACK))
1064 return;
1065
1066 ret = btrfs_del_ordered_inode(inode);
1067 if (ret == 1) {
1068 atomic_dec(&inode->i_count);
1069 }
1070 }
1071
1072 void btrfs_delete_inode(struct inode *inode)
1073 {
1074 struct btrfs_trans_handle *trans;
1075 struct btrfs_root *root = BTRFS_I(inode)->root;
1076 unsigned long nr;
1077 int ret;
1078
1079 truncate_inode_pages(&inode->i_data, 0);
1080 if (is_bad_inode(inode)) {
1081 goto no_delete;
1082 }
1083
1084 inode->i_size = 0;
1085 mutex_lock(&root->fs_info->fs_mutex);
1086 trans = btrfs_start_transaction(root, 1);
1087
1088 btrfs_set_trans_block_group(trans, inode);
1089 ret = btrfs_truncate_in_trans(trans, root, inode, 0);
1090 if (ret)
1091 goto no_delete_lock;
1092
1093 nr = trans->blocks_used;
1094 clear_inode(inode);
1095
1096 btrfs_end_transaction(trans, root);
1097 mutex_unlock(&root->fs_info->fs_mutex);
1098 btrfs_btree_balance_dirty(root, nr);
1099 btrfs_throttle(root);
1100 return;
1101
1102 no_delete_lock:
1103 nr = trans->blocks_used;
1104 btrfs_end_transaction(trans, root);
1105 mutex_unlock(&root->fs_info->fs_mutex);
1106 btrfs_btree_balance_dirty(root, nr);
1107 btrfs_throttle(root);
1108 no_delete:
1109 clear_inode(inode);
1110 }
1111
1112 /*
1113 * this returns the key found in the dir entry in the location pointer.
1114 * If no dir entries were found, location->objectid is 0.
1115 */
1116 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
1117 struct btrfs_key *location)
1118 {
1119 const char *name = dentry->d_name.name;
1120 int namelen = dentry->d_name.len;
1121 struct btrfs_dir_item *di;
1122 struct btrfs_path *path;
1123 struct btrfs_root *root = BTRFS_I(dir)->root;
1124 int ret = 0;
1125
1126 if (namelen == 1 && strcmp(name, ".") == 0) {
1127 location->objectid = dir->i_ino;
1128 location->type = BTRFS_INODE_ITEM_KEY;
1129 location->offset = 0;
1130 return 0;
1131 }
1132 path = btrfs_alloc_path();
1133 BUG_ON(!path);
1134
1135 if (namelen == 2 && strcmp(name, "..") == 0) {
1136 struct btrfs_key key;
1137 struct extent_buffer *leaf;
1138 u32 nritems;
1139 int slot;
1140
1141 key.objectid = dir->i_ino;
1142 btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
1143 key.offset = 0;
1144 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1145 BUG_ON(ret == 0);
1146 ret = 0;
1147
1148 leaf = path->nodes[0];
1149 slot = path->slots[0];
1150 nritems = btrfs_header_nritems(leaf);
1151 if (slot >= nritems)
1152 goto out_err;
1153
1154 btrfs_item_key_to_cpu(leaf, &key, slot);
1155 if (key.objectid != dir->i_ino ||
1156 key.type != BTRFS_INODE_REF_KEY) {
1157 goto out_err;
1158 }
1159 location->objectid = key.offset;
1160 location->type = BTRFS_INODE_ITEM_KEY;
1161 location->offset = 0;
1162 goto out;
1163 }
1164
1165 di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
1166 namelen, 0);
1167 if (IS_ERR(di))
1168 ret = PTR_ERR(di);
1169 if (!di || IS_ERR(di)) {
1170 goto out_err;
1171 }
1172 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
1173 out:
1174 btrfs_free_path(path);
1175 return ret;
1176 out_err:
1177 location->objectid = 0;
1178 goto out;
1179 }
1180
1181 /*
1182 * when we hit a tree root in a directory, the btrfs part of the inode
1183 * needs to be changed to reflect the root directory of the tree root. This
1184 * is kind of like crossing a mount point.
1185 */
1186 static int fixup_tree_root_location(struct btrfs_root *root,
1187 struct btrfs_key *location,
1188 struct btrfs_root **sub_root,
1189 struct dentry *dentry)
1190 {
1191 struct btrfs_path *path;
1192 struct btrfs_root_item *ri;
1193
1194 if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
1195 return 0;
1196 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1197 return 0;
1198
1199 path = btrfs_alloc_path();
1200 BUG_ON(!path);
1201 mutex_lock(&root->fs_info->fs_mutex);
1202
1203 *sub_root = btrfs_read_fs_root(root->fs_info, location,
1204 dentry->d_name.name,
1205 dentry->d_name.len);
1206 if (IS_ERR(*sub_root))
1207 return PTR_ERR(*sub_root);
1208
1209 ri = &(*sub_root)->root_item;
1210 location->objectid = btrfs_root_dirid(ri);
1211 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
1212 location->offset = 0;
1213
1214 btrfs_free_path(path);
1215 mutex_unlock(&root->fs_info->fs_mutex);
1216 return 0;
1217 }
1218
1219 static int btrfs_init_locked_inode(struct inode *inode, void *p)
1220 {
1221 struct btrfs_iget_args *args = p;
1222 inode->i_ino = args->ino;
1223 BTRFS_I(inode)->root = args->root;
1224 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
1225 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
1226 inode->i_mapping, GFP_NOFS);
1227 return 0;
1228 }
1229
1230 static int btrfs_find_actor(struct inode *inode, void *opaque)
1231 {
1232 struct btrfs_iget_args *args = opaque;
1233 return (args->ino == inode->i_ino &&
1234 args->root == BTRFS_I(inode)->root);
1235 }
1236
1237 struct inode *btrfs_ilookup(struct super_block *s, u64 objectid,
1238 u64 root_objectid)
1239 {
1240 struct btrfs_iget_args args;
1241 args.ino = objectid;
1242 args.root = btrfs_lookup_fs_root(btrfs_sb(s)->fs_info, root_objectid);
1243
1244 if (!args.root)
1245 return NULL;
1246
1247 return ilookup5(s, objectid, btrfs_find_actor, (void *)&args);
1248 }
1249
1250 struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
1251 struct btrfs_root *root)
1252 {
1253 struct inode *inode;
1254 struct btrfs_iget_args args;
1255 args.ino = objectid;
1256 args.root = root;
1257
1258 inode = iget5_locked(s, objectid, btrfs_find_actor,
1259 btrfs_init_locked_inode,
1260 (void *)&args);
1261 return inode;
1262 }
1263
1264 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
1265 struct nameidata *nd)
1266 {
1267 struct inode * inode;
1268 struct btrfs_inode *bi = BTRFS_I(dir);
1269 struct btrfs_root *root = bi->root;
1270 struct btrfs_root *sub_root = root;
1271 struct btrfs_key location;
1272 int ret;
1273
1274 if (dentry->d_name.len > BTRFS_NAME_LEN)
1275 return ERR_PTR(-ENAMETOOLONG);
1276
1277 mutex_lock(&root->fs_info->fs_mutex);
1278 ret = btrfs_inode_by_name(dir, dentry, &location);
1279 mutex_unlock(&root->fs_info->fs_mutex);
1280
1281 if (ret < 0)
1282 return ERR_PTR(ret);
1283
1284 inode = NULL;
1285 if (location.objectid) {
1286 ret = fixup_tree_root_location(root, &location, &sub_root,
1287 dentry);
1288 if (ret < 0)
1289 return ERR_PTR(ret);
1290 if (ret > 0)
1291 return ERR_PTR(-ENOENT);
1292 inode = btrfs_iget_locked(dir->i_sb, location.objectid,
1293 sub_root);
1294 if (!inode)
1295 return ERR_PTR(-EACCES);
1296 if (inode->i_state & I_NEW) {
1297 /* the inode and parent dir are two different roots */
1298 if (sub_root != root) {
1299 igrab(inode);
1300 sub_root->inode = inode;
1301 }
1302 BTRFS_I(inode)->root = sub_root;
1303 memcpy(&BTRFS_I(inode)->location, &location,
1304 sizeof(location));
1305 btrfs_read_locked_inode(inode);
1306 unlock_new_inode(inode);
1307 }
1308 }
1309 return d_splice_alias(inode, dentry);
1310 }
1311
1312 static unsigned char btrfs_filetype_table[] = {
1313 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
1314 };
1315
1316 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
1317 {
1318 struct inode *inode = filp->f_dentry->d_inode;
1319 struct btrfs_root *root = BTRFS_I(inode)->root;
1320 struct btrfs_item *item;
1321 struct btrfs_dir_item *di;
1322 struct btrfs_key key;
1323 struct btrfs_key found_key;
1324 struct btrfs_path *path;
1325 int ret;
1326 u32 nritems;
1327 struct extent_buffer *leaf;
1328 int slot;
1329 int advance;
1330 unsigned char d_type;
1331 int over = 0;
1332 u32 di_cur;
1333 u32 di_total;
1334 u32 di_len;
1335 int key_type = BTRFS_DIR_INDEX_KEY;
1336 char tmp_name[32];
1337 char *name_ptr;
1338 int name_len;
1339
1340 /* FIXME, use a real flag for deciding about the key type */
1341 if (root->fs_info->tree_root == root)
1342 key_type = BTRFS_DIR_ITEM_KEY;
1343
1344 /* special case for "." */
1345 if (filp->f_pos == 0) {
1346 over = filldir(dirent, ".", 1,
1347 1, inode->i_ino,
1348 DT_DIR);
1349 if (over)
1350 return 0;
1351 filp->f_pos = 1;
1352 }
1353
1354 mutex_lock(&root->fs_info->fs_mutex);
1355 key.objectid = inode->i_ino;
1356 path = btrfs_alloc_path();
1357 path->reada = 2;
1358
1359 /* special case for .., just use the back ref */
1360 if (filp->f_pos == 1) {
1361 btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
1362 key.offset = 0;
1363 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1364 BUG_ON(ret == 0);
1365 leaf = path->nodes[0];
1366 slot = path->slots[0];
1367 nritems = btrfs_header_nritems(leaf);
1368 if (slot >= nritems) {
1369 btrfs_release_path(root, path);
1370 goto read_dir_items;
1371 }
1372 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1373 btrfs_release_path(root, path);
1374 if (found_key.objectid != key.objectid ||
1375 found_key.type != BTRFS_INODE_REF_KEY)
1376 goto read_dir_items;
1377 over = filldir(dirent, "..", 2,
1378 2, found_key.offset, DT_DIR);
1379 if (over)
1380 goto nopos;
1381 filp->f_pos = 2;
1382 }
1383
1384 read_dir_items:
1385 btrfs_set_key_type(&key, key_type);
1386 key.offset = filp->f_pos;
1387
1388 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1389 if (ret < 0)
1390 goto err;
1391 advance = 0;
1392 while(1) {
1393 leaf = path->nodes[0];
1394 nritems = btrfs_header_nritems(leaf);
1395 slot = path->slots[0];
1396 if (advance || slot >= nritems) {
1397 if (slot >= nritems -1) {
1398 ret = btrfs_next_leaf(root, path);
1399 if (ret)
1400 break;
1401 leaf = path->nodes[0];
1402 nritems = btrfs_header_nritems(leaf);
1403 slot = path->slots[0];
1404 } else {
1405 slot++;
1406 path->slots[0]++;
1407 }
1408 }
1409 advance = 1;
1410 item = btrfs_item_nr(leaf, slot);
1411 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1412
1413 if (found_key.objectid != key.objectid)
1414 break;
1415 if (btrfs_key_type(&found_key) != key_type)
1416 break;
1417 if (found_key.offset < filp->f_pos)
1418 continue;
1419
1420 filp->f_pos = found_key.offset;
1421 advance = 1;
1422 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
1423 di_cur = 0;
1424 di_total = btrfs_item_size(leaf, item);
1425 while(di_cur < di_total) {
1426 struct btrfs_key location;
1427
1428 name_len = btrfs_dir_name_len(leaf, di);
1429 if (name_len < 32) {
1430 name_ptr = tmp_name;
1431 } else {
1432 name_ptr = kmalloc(name_len, GFP_NOFS);
1433 BUG_ON(!name_ptr);
1434 }
1435 read_extent_buffer(leaf, name_ptr,
1436 (unsigned long)(di + 1), name_len);
1437
1438 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
1439 btrfs_dir_item_key_to_cpu(leaf, di, &location);
1440 over = filldir(dirent, name_ptr, name_len,
1441 found_key.offset,
1442 location.objectid,
1443 d_type);
1444
1445 if (name_ptr != tmp_name)
1446 kfree(name_ptr);
1447
1448 if (over)
1449 goto nopos;
1450 di_len = btrfs_dir_name_len(leaf, di) +
1451 btrfs_dir_data_len(leaf, di) +sizeof(*di);
1452 di_cur += di_len;
1453 di = (struct btrfs_dir_item *)((char *)di + di_len);
1454 }
1455 }
1456 filp->f_pos = INT_LIMIT(typeof(filp->f_pos));
1457 nopos:
1458 ret = 0;
1459 err:
1460 btrfs_release_path(root, path);
1461 btrfs_free_path(path);
1462 mutex_unlock(&root->fs_info->fs_mutex);
1463 return ret;
1464 }
1465
1466 int btrfs_write_inode(struct inode *inode, int wait)
1467 {
1468 struct btrfs_root *root = BTRFS_I(inode)->root;
1469 struct btrfs_trans_handle *trans;
1470 int ret = 0;
1471
1472 if (wait) {
1473 mutex_lock(&root->fs_info->fs_mutex);
1474 trans = btrfs_start_transaction(root, 1);
1475 btrfs_set_trans_block_group(trans, inode);
1476 ret = btrfs_commit_transaction(trans, root);
1477 mutex_unlock(&root->fs_info->fs_mutex);
1478 }
1479 return ret;
1480 }
1481
1482 /*
1483 * This is somewhat expensive, updating the tree every time the
1484 * inode changes. But, it is most likely to find the inode in cache.
1485 * FIXME, needs more benchmarking...there are no reasons other than performance
1486 * to keep or drop this code.
1487 */
1488 void btrfs_dirty_inode(struct inode *inode)
1489 {
1490 struct btrfs_root *root = BTRFS_I(inode)->root;
1491 struct btrfs_trans_handle *trans;
1492
1493 mutex_lock(&root->fs_info->fs_mutex);
1494 trans = btrfs_start_transaction(root, 1);
1495 btrfs_set_trans_block_group(trans, inode);
1496 btrfs_update_inode(trans, root, inode);
1497 btrfs_end_transaction(trans, root);
1498 mutex_unlock(&root->fs_info->fs_mutex);
1499 }
1500
1501 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
1502 struct btrfs_root *root,
1503 u64 objectid,
1504 struct btrfs_block_group_cache *group,
1505 int mode)
1506 {
1507 struct inode *inode;
1508 struct btrfs_inode_item *inode_item;
1509 struct btrfs_key *location;
1510 struct btrfs_path *path;
1511 int ret;
1512 int owner;
1513
1514 path = btrfs_alloc_path();
1515 BUG_ON(!path);
1516
1517 inode = new_inode(root->fs_info->sb);
1518 if (!inode)
1519 return ERR_PTR(-ENOMEM);
1520
1521 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
1522 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
1523 inode->i_mapping, GFP_NOFS);
1524 BTRFS_I(inode)->root = root;
1525
1526 if (mode & S_IFDIR)
1527 owner = 0;
1528 else
1529 owner = 1;
1530 group = btrfs_find_block_group(root, group, 0, 0, owner);
1531 BTRFS_I(inode)->block_group = group;
1532 BTRFS_I(inode)->flags = 0;
1533 ret = btrfs_insert_empty_inode(trans, root, path, objectid);
1534 if (ret)
1535 goto fail;
1536
1537 inode->i_uid = current->fsuid;
1538 inode->i_gid = current->fsgid;
1539 inode->i_mode = mode;
1540 inode->i_ino = objectid;
1541 inode->i_blocks = 0;
1542 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1543 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1544 struct btrfs_inode_item);
1545 fill_inode_item(path->nodes[0], inode_item, inode);
1546 btrfs_mark_buffer_dirty(path->nodes[0]);
1547 btrfs_free_path(path);
1548
1549 location = &BTRFS_I(inode)->location;
1550 location->objectid = objectid;
1551 location->offset = 0;
1552 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
1553
1554 insert_inode_hash(inode);
1555 return inode;
1556 fail:
1557 btrfs_free_path(path);
1558 return ERR_PTR(ret);
1559 }
1560
1561 static inline u8 btrfs_inode_type(struct inode *inode)
1562 {
1563 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
1564 }
1565
1566 static int btrfs_add_link(struct btrfs_trans_handle *trans,
1567 struct dentry *dentry, struct inode *inode)
1568 {
1569 int ret;
1570 struct btrfs_key key;
1571 struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
1572 struct inode *parent_inode;
1573
1574 key.objectid = inode->i_ino;
1575 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
1576 key.offset = 0;
1577
1578 ret = btrfs_insert_dir_item(trans, root,
1579 dentry->d_name.name, dentry->d_name.len,
1580 dentry->d_parent->d_inode->i_ino,
1581 &key, btrfs_inode_type(inode));
1582 if (ret == 0) {
1583 ret = btrfs_insert_inode_ref(trans, root,
1584 dentry->d_name.name,
1585 dentry->d_name.len,
1586 inode->i_ino,
1587 dentry->d_parent->d_inode->i_ino);
1588 parent_inode = dentry->d_parent->d_inode;
1589 parent_inode->i_size += dentry->d_name.len * 2;
1590 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
1591 ret = btrfs_update_inode(trans, root,
1592 dentry->d_parent->d_inode);
1593 }
1594 return ret;
1595 }
1596
1597 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
1598 struct dentry *dentry, struct inode *inode)
1599 {
1600 int err = btrfs_add_link(trans, dentry, inode);
1601 if (!err) {
1602 d_instantiate(dentry, inode);
1603 return 0;
1604 }
1605 if (err > 0)
1606 err = -EEXIST;
1607 return err;
1608 }
1609
1610 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
1611 int mode, dev_t rdev)
1612 {
1613 struct btrfs_trans_handle *trans;
1614 struct btrfs_root *root = BTRFS_I(dir)->root;
1615 struct inode *inode = NULL;
1616 int err;
1617 int drop_inode = 0;
1618 u64 objectid;
1619 unsigned long nr = 0;
1620
1621 if (!new_valid_dev(rdev))
1622 return -EINVAL;
1623
1624 mutex_lock(&root->fs_info->fs_mutex);
1625 err = btrfs_check_free_space(root, 1, 0);
1626 if (err)
1627 goto fail;
1628
1629 trans = btrfs_start_transaction(root, 1);
1630 btrfs_set_trans_block_group(trans, dir);
1631
1632 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1633 if (err) {
1634 err = -ENOSPC;
1635 goto out_unlock;
1636 }
1637
1638 inode = btrfs_new_inode(trans, root, objectid,
1639 BTRFS_I(dir)->block_group, mode);
1640 err = PTR_ERR(inode);
1641 if (IS_ERR(inode))
1642 goto out_unlock;
1643
1644 btrfs_set_trans_block_group(trans, inode);
1645 err = btrfs_add_nondir(trans, dentry, inode);
1646 if (err)
1647 drop_inode = 1;
1648 else {
1649 inode->i_op = &btrfs_special_inode_operations;
1650 init_special_inode(inode, inode->i_mode, rdev);
1651 btrfs_update_inode(trans, root, inode);
1652 }
1653 dir->i_sb->s_dirt = 1;
1654 btrfs_update_inode_block_group(trans, inode);
1655 btrfs_update_inode_block_group(trans, dir);
1656 out_unlock:
1657 nr = trans->blocks_used;
1658 btrfs_end_transaction(trans, root);
1659 fail:
1660 mutex_unlock(&root->fs_info->fs_mutex);
1661
1662 if (drop_inode) {
1663 inode_dec_link_count(inode);
1664 iput(inode);
1665 }
1666 btrfs_btree_balance_dirty(root, nr);
1667 btrfs_throttle(root);
1668 return err;
1669 }
1670
1671 static int btrfs_create(struct inode *dir, struct dentry *dentry,
1672 int mode, struct nameidata *nd)
1673 {
1674 struct btrfs_trans_handle *trans;
1675 struct btrfs_root *root = BTRFS_I(dir)->root;
1676 struct inode *inode = NULL;
1677 int err;
1678 int drop_inode = 0;
1679 unsigned long nr = 0;
1680 u64 objectid;
1681
1682 mutex_lock(&root->fs_info->fs_mutex);
1683 err = btrfs_check_free_space(root, 1, 0);
1684 if (err)
1685 goto fail;
1686 trans = btrfs_start_transaction(root, 1);
1687 btrfs_set_trans_block_group(trans, dir);
1688
1689 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1690 if (err) {
1691 err = -ENOSPC;
1692 goto out_unlock;
1693 }
1694
1695 inode = btrfs_new_inode(trans, root, objectid,
1696 BTRFS_I(dir)->block_group, mode);
1697 err = PTR_ERR(inode);
1698 if (IS_ERR(inode))
1699 goto out_unlock;
1700
1701 btrfs_set_trans_block_group(trans, inode);
1702 err = btrfs_add_nondir(trans, dentry, inode);
1703 if (err)
1704 drop_inode = 1;
1705 else {
1706 inode->i_mapping->a_ops = &btrfs_aops;
1707 inode->i_fop = &btrfs_file_operations;
1708 inode->i_op = &btrfs_file_inode_operations;
1709 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
1710 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
1711 inode->i_mapping, GFP_NOFS);
1712 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
1713 }
1714 dir->i_sb->s_dirt = 1;
1715 btrfs_update_inode_block_group(trans, inode);
1716 btrfs_update_inode_block_group(trans, dir);
1717 out_unlock:
1718 nr = trans->blocks_used;
1719 btrfs_end_transaction(trans, root);
1720 fail:
1721 mutex_unlock(&root->fs_info->fs_mutex);
1722
1723 if (drop_inode) {
1724 inode_dec_link_count(inode);
1725 iput(inode);
1726 }
1727 btrfs_btree_balance_dirty(root, nr);
1728 btrfs_throttle(root);
1729 return err;
1730 }
1731
1732 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
1733 struct dentry *dentry)
1734 {
1735 struct btrfs_trans_handle *trans;
1736 struct btrfs_root *root = BTRFS_I(dir)->root;
1737 struct inode *inode = old_dentry->d_inode;
1738 unsigned long nr = 0;
1739 int err;
1740 int drop_inode = 0;
1741
1742 if (inode->i_nlink == 0)
1743 return -ENOENT;
1744
1745 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
1746 inode->i_nlink++;
1747 #else
1748 inc_nlink(inode);
1749 #endif
1750 mutex_lock(&root->fs_info->fs_mutex);
1751 err = btrfs_check_free_space(root, 1, 0);
1752 if (err)
1753 goto fail;
1754 trans = btrfs_start_transaction(root, 1);
1755
1756 btrfs_set_trans_block_group(trans, dir);
1757 atomic_inc(&inode->i_count);
1758 err = btrfs_add_nondir(trans, dentry, inode);
1759
1760 if (err)
1761 drop_inode = 1;
1762
1763 dir->i_sb->s_dirt = 1;
1764 btrfs_update_inode_block_group(trans, dir);
1765 err = btrfs_update_inode(trans, root, inode);
1766
1767 if (err)
1768 drop_inode = 1;
1769
1770 nr = trans->blocks_used;
1771 btrfs_end_transaction(trans, root);
1772 fail:
1773 mutex_unlock(&root->fs_info->fs_mutex);
1774
1775 if (drop_inode) {
1776 inode_dec_link_count(inode);
1777 iput(inode);
1778 }
1779 btrfs_btree_balance_dirty(root, nr);
1780 btrfs_throttle(root);
1781 return err;
1782 }
1783
1784 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
1785 {
1786 struct inode *inode;
1787 struct btrfs_trans_handle *trans;
1788 struct btrfs_root *root = BTRFS_I(dir)->root;
1789 int err = 0;
1790 int drop_on_err = 0;
1791 u64 objectid;
1792 unsigned long nr = 1;
1793
1794 mutex_lock(&root->fs_info->fs_mutex);
1795 err = btrfs_check_free_space(root, 1, 0);
1796 if (err)
1797 goto out_unlock;
1798
1799 trans = btrfs_start_transaction(root, 1);
1800 btrfs_set_trans_block_group(trans, dir);
1801
1802 if (IS_ERR(trans)) {
1803 err = PTR_ERR(trans);
1804 goto out_unlock;
1805 }
1806
1807 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1808 if (err) {
1809 err = -ENOSPC;
1810 goto out_unlock;
1811 }
1812
1813 inode = btrfs_new_inode(trans, root, objectid,
1814 BTRFS_I(dir)->block_group, S_IFDIR | mode);
1815 if (IS_ERR(inode)) {
1816 err = PTR_ERR(inode);
1817 goto out_fail;
1818 }
1819
1820 drop_on_err = 1;
1821 inode->i_op = &btrfs_dir_inode_operations;
1822 inode->i_fop = &btrfs_dir_file_operations;
1823 btrfs_set_trans_block_group(trans, inode);
1824
1825 inode->i_size = 0;
1826 err = btrfs_update_inode(trans, root, inode);
1827 if (err)
1828 goto out_fail;
1829
1830 err = btrfs_add_link(trans, dentry, inode);
1831 if (err)
1832 goto out_fail;
1833
1834 d_instantiate(dentry, inode);
1835 drop_on_err = 0;
1836 dir->i_sb->s_dirt = 1;
1837 btrfs_update_inode_block_group(trans, inode);
1838 btrfs_update_inode_block_group(trans, dir);
1839
1840 out_fail:
1841 nr = trans->blocks_used;
1842 btrfs_end_transaction(trans, root);
1843
1844 out_unlock:
1845 mutex_unlock(&root->fs_info->fs_mutex);
1846 if (drop_on_err)
1847 iput(inode);
1848 btrfs_btree_balance_dirty(root, nr);
1849 btrfs_throttle(root);
1850 return err;
1851 }
1852
1853 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
1854 size_t pg_offset, u64 start, u64 len,
1855 int create)
1856 {
1857 int ret;
1858 int err = 0;
1859 u64 bytenr;
1860 u64 extent_start = 0;
1861 u64 extent_end = 0;
1862 u64 objectid = inode->i_ino;
1863 u32 found_type;
1864 struct btrfs_path *path;
1865 struct btrfs_root *root = BTRFS_I(inode)->root;
1866 struct btrfs_file_extent_item *item;
1867 struct extent_buffer *leaf;
1868 struct btrfs_key found_key;
1869 struct extent_map *em = NULL;
1870 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1871 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1872 struct btrfs_trans_handle *trans = NULL;
1873
1874 path = btrfs_alloc_path();
1875 BUG_ON(!path);
1876 mutex_lock(&root->fs_info->fs_mutex);
1877
1878 again:
1879 spin_lock(&em_tree->lock);
1880 em = lookup_extent_mapping(em_tree, start, len);
1881 spin_unlock(&em_tree->lock);
1882
1883 if (em) {
1884 if (em->start > start) {
1885 printk("get_extent lookup [%Lu %Lu] em [%Lu %Lu]\n",
1886 start, len, em->start, em->len);
1887 WARN_ON(1);
1888 }
1889 if (em->block_start == EXTENT_MAP_INLINE && page)
1890 free_extent_map(em);
1891 else
1892 goto out;
1893 }
1894 em = alloc_extent_map(GFP_NOFS);
1895 if (!em) {
1896 err = -ENOMEM;
1897 goto out;
1898 }
1899
1900 em->start = EXTENT_MAP_HOLE;
1901 em->len = (u64)-1;
1902 em->bdev = inode->i_sb->s_bdev;
1903 ret = btrfs_lookup_file_extent(trans, root, path,
1904 objectid, start, trans != NULL);
1905 if (ret < 0) {
1906 err = ret;
1907 goto out;
1908 }
1909
1910 if (ret != 0) {
1911 if (path->slots[0] == 0)
1912 goto not_found;
1913 path->slots[0]--;
1914 }
1915
1916 leaf = path->nodes[0];
1917 item = btrfs_item_ptr(leaf, path->slots[0],
1918 struct btrfs_file_extent_item);
1919 /* are we inside the extent that was found? */
1920 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1921 found_type = btrfs_key_type(&found_key);
1922 if (found_key.objectid != objectid ||
1923 found_type != BTRFS_EXTENT_DATA_KEY) {
1924 goto not_found;
1925 }
1926
1927 found_type = btrfs_file_extent_type(leaf, item);
1928 extent_start = found_key.offset;
1929 if (found_type == BTRFS_FILE_EXTENT_REG) {
1930 extent_end = extent_start +
1931 btrfs_file_extent_num_bytes(leaf, item);
1932 err = 0;
1933 if (start < extent_start || start >= extent_end) {
1934 em->start = start;
1935 if (start < extent_start) {
1936 if (start + len <= extent_start)
1937 goto not_found;
1938 em->len = extent_end - extent_start;
1939 } else {
1940 em->len = len;
1941 }
1942 goto not_found_em;
1943 }
1944 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
1945 if (bytenr == 0) {
1946 em->start = extent_start;
1947 em->len = extent_end - extent_start;
1948 em->block_start = EXTENT_MAP_HOLE;
1949 goto insert;
1950 }
1951 bytenr += btrfs_file_extent_offset(leaf, item);
1952 em->block_start = bytenr;
1953 em->start = extent_start;
1954 em->len = extent_end - extent_start;
1955 goto insert;
1956 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
1957 u64 page_start;
1958 unsigned long ptr;
1959 char *map;
1960 size_t size;
1961 size_t extent_offset;
1962 size_t copy_size;
1963
1964 size = btrfs_file_extent_inline_len(leaf, btrfs_item_nr(leaf,
1965 path->slots[0]));
1966 extent_end = (extent_start + size + root->sectorsize - 1) &
1967 ~((u64)root->sectorsize - 1);
1968 if (start < extent_start || start >= extent_end) {
1969 em->start = start;
1970 if (start < extent_start) {
1971 if (start + len <= extent_start)
1972 goto not_found;
1973 em->len = extent_end - extent_start;
1974 } else {
1975 em->len = len;
1976 }
1977 goto not_found_em;
1978 }
1979 em->block_start = EXTENT_MAP_INLINE;
1980
1981 if (!page) {
1982 em->start = extent_start;
1983 em->len = size;
1984 goto out;
1985 }
1986
1987 page_start = page_offset(page) + pg_offset;
1988 extent_offset = page_start - extent_start;
1989 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
1990 size - extent_offset);
1991 em->start = extent_start + extent_offset;
1992 em->len = (copy_size + root->sectorsize - 1) &
1993 ~((u64)root->sectorsize - 1);
1994 map = kmap(page);
1995 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
1996 if (create == 0 && !PageUptodate(page)) {
1997 read_extent_buffer(leaf, map + pg_offset, ptr,
1998 copy_size);
1999 flush_dcache_page(page);
2000 } else if (create && PageUptodate(page)) {
2001 if (!trans) {
2002 kunmap(page);
2003 free_extent_map(em);
2004 em = NULL;
2005 btrfs_release_path(root, path);
2006 trans = btrfs_start_transaction(root, 1);
2007 goto again;
2008 }
2009 write_extent_buffer(leaf, map + pg_offset, ptr,
2010 copy_size);
2011 btrfs_mark_buffer_dirty(leaf);
2012 }
2013 kunmap(page);
2014 set_extent_uptodate(io_tree, em->start,
2015 extent_map_end(em) - 1, GFP_NOFS);
2016 goto insert;
2017 } else {
2018 printk("unkknown found_type %d\n", found_type);
2019 WARN_ON(1);
2020 }
2021 not_found:
2022 em->start = start;
2023 em->len = len;
2024 not_found_em:
2025 em->block_start = EXTENT_MAP_HOLE;
2026 insert:
2027 btrfs_release_path(root, path);
2028 if (em->start > start || extent_map_end(em) <= start) {
2029 printk("bad extent! em: [%Lu %Lu] passed [%Lu %Lu]\n", em->start, em->len, start, len);
2030 err = -EIO;
2031 goto out;
2032 }
2033
2034 err = 0;
2035 spin_lock(&em_tree->lock);
2036 ret = add_extent_mapping(em_tree, em);
2037 if (ret == -EEXIST) {
2038 free_extent_map(em);
2039 em = lookup_extent_mapping(em_tree, start, len);
2040 if (!em) {
2041 err = -EIO;
2042 printk("failing to insert %Lu %Lu\n", start, len);
2043 }
2044 }
2045 spin_unlock(&em_tree->lock);
2046 out:
2047 btrfs_free_path(path);
2048 if (trans) {
2049 ret = btrfs_end_transaction(trans, root);
2050 if (!err)
2051 err = ret;
2052 }
2053 mutex_unlock(&root->fs_info->fs_mutex);
2054 if (err) {
2055 free_extent_map(em);
2056 WARN_ON(1);
2057 return ERR_PTR(err);
2058 }
2059 return em;
2060 }
2061
2062 static sector_t btrfs_bmap(struct address_space *mapping, sector_t iblock)
2063 {
2064 return extent_bmap(mapping, iblock, btrfs_get_extent);
2065 }
2066
2067 int btrfs_readpage(struct file *file, struct page *page)
2068 {
2069 struct extent_io_tree *tree;
2070 tree = &BTRFS_I(page->mapping->host)->io_tree;
2071 return extent_read_full_page(tree, page, btrfs_get_extent);
2072 }
2073
2074 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
2075 {
2076 struct extent_io_tree *tree;
2077
2078
2079 if (current->flags & PF_MEMALLOC) {
2080 redirty_page_for_writepage(wbc, page);
2081 unlock_page(page);
2082 return 0;
2083 }
2084 tree = &BTRFS_I(page->mapping->host)->io_tree;
2085 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
2086 }
2087
2088 static int btrfs_writepages(struct address_space *mapping,
2089 struct writeback_control *wbc)
2090 {
2091 struct extent_io_tree *tree;
2092 tree = &BTRFS_I(mapping->host)->io_tree;
2093 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
2094 }
2095
2096 static int
2097 btrfs_readpages(struct file *file, struct address_space *mapping,
2098 struct list_head *pages, unsigned nr_pages)
2099 {
2100 struct extent_io_tree *tree;
2101 tree = &BTRFS_I(mapping->host)->io_tree;
2102 return extent_readpages(tree, mapping, pages, nr_pages,
2103 btrfs_get_extent);
2104 }
2105
2106 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
2107 {
2108 struct extent_io_tree *tree;
2109 struct extent_map_tree *map;
2110 int ret;
2111
2112 tree = &BTRFS_I(page->mapping->host)->io_tree;
2113 map = &BTRFS_I(page->mapping->host)->extent_tree;
2114 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
2115 if (ret == 1) {
2116 ClearPagePrivate(page);
2117 set_page_private(page, 0);
2118 page_cache_release(page);
2119 }
2120 return ret;
2121 }
2122
2123 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
2124 {
2125 struct extent_io_tree *tree;
2126
2127 tree = &BTRFS_I(page->mapping->host)->io_tree;
2128 extent_invalidatepage(tree, page, offset);
2129 btrfs_releasepage(page, GFP_NOFS);
2130 }
2131
2132 /*
2133 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
2134 * called from a page fault handler when a page is first dirtied. Hence we must
2135 * be careful to check for EOF conditions here. We set the page up correctly
2136 * for a written page which means we get ENOSPC checking when writing into
2137 * holes and correct delalloc and unwritten extent mapping on filesystems that
2138 * support these features.
2139 *
2140 * We are not allowed to take the i_mutex here so we have to play games to
2141 * protect against truncate races as the page could now be beyond EOF. Because
2142 * vmtruncate() writes the inode size before removing pages, once we have the
2143 * page lock we can determine safely if the page is beyond EOF. If it is not
2144 * beyond EOF, then the page is guaranteed safe against truncation until we
2145 * unlock the page.
2146 */
2147 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
2148 {
2149 struct inode *inode = fdentry(vma->vm_file)->d_inode;
2150 struct btrfs_root *root = BTRFS_I(inode)->root;
2151 unsigned long end;
2152 loff_t size;
2153 int ret;
2154 u64 page_start;
2155
2156 mutex_lock(&root->fs_info->fs_mutex);
2157 ret = btrfs_check_free_space(root, PAGE_CACHE_SIZE, 0);
2158 mutex_unlock(&root->fs_info->fs_mutex);
2159 if (ret)
2160 goto out;
2161
2162 ret = -EINVAL;
2163
2164 lock_page(page);
2165 wait_on_page_writeback(page);
2166 size = i_size_read(inode);
2167 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2168
2169 if ((page->mapping != inode->i_mapping) ||
2170 (page_start > size)) {
2171 /* page got truncated out from underneath us */
2172 goto out_unlock;
2173 }
2174
2175 /* page is wholly or partially inside EOF */
2176 if (page_start + PAGE_CACHE_SIZE > size)
2177 end = size & ~PAGE_CACHE_MASK;
2178 else
2179 end = PAGE_CACHE_SIZE;
2180
2181 ret = btrfs_cow_one_page(inode, page, end);
2182
2183 out_unlock:
2184 unlock_page(page);
2185 out:
2186 return ret;
2187 }
2188
2189 static void btrfs_truncate(struct inode *inode)
2190 {
2191 struct btrfs_root *root = BTRFS_I(inode)->root;
2192 int ret;
2193 struct btrfs_trans_handle *trans;
2194 unsigned long nr;
2195
2196 if (!S_ISREG(inode->i_mode))
2197 return;
2198 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
2199 return;
2200
2201 btrfs_truncate_page(inode->i_mapping, inode->i_size);
2202
2203 mutex_lock(&root->fs_info->fs_mutex);
2204 trans = btrfs_start_transaction(root, 1);
2205 btrfs_set_trans_block_group(trans, inode);
2206
2207 /* FIXME, add redo link to tree so we don't leak on crash */
2208 ret = btrfs_truncate_in_trans(trans, root, inode,
2209 BTRFS_EXTENT_DATA_KEY);
2210 btrfs_update_inode(trans, root, inode);
2211 nr = trans->blocks_used;
2212
2213 ret = btrfs_end_transaction(trans, root);
2214 BUG_ON(ret);
2215 mutex_unlock(&root->fs_info->fs_mutex);
2216 btrfs_btree_balance_dirty(root, nr);
2217 btrfs_throttle(root);
2218 }
2219
2220 static int noinline create_subvol(struct btrfs_root *root, char *name,
2221 int namelen)
2222 {
2223 struct btrfs_trans_handle *trans;
2224 struct btrfs_key key;
2225 struct btrfs_root_item root_item;
2226 struct btrfs_inode_item *inode_item;
2227 struct extent_buffer *leaf;
2228 struct btrfs_root *new_root = root;
2229 struct inode *inode;
2230 struct inode *dir;
2231 int ret;
2232 int err;
2233 u64 objectid;
2234 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
2235 unsigned long nr = 1;
2236
2237 mutex_lock(&root->fs_info->fs_mutex);
2238 ret = btrfs_check_free_space(root, 1, 0);
2239 if (ret)
2240 goto fail_commit;
2241
2242 trans = btrfs_start_transaction(root, 1);
2243 BUG_ON(!trans);
2244
2245 ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
2246 0, &objectid);
2247 if (ret)
2248 goto fail;
2249
2250 leaf = __btrfs_alloc_free_block(trans, root, root->leafsize,
2251 objectid, trans->transid, 0, 0,
2252 0, 0);
2253 if (IS_ERR(leaf))
2254 return PTR_ERR(leaf);
2255
2256 btrfs_set_header_nritems(leaf, 0);
2257 btrfs_set_header_level(leaf, 0);
2258 btrfs_set_header_bytenr(leaf, leaf->start);
2259 btrfs_set_header_generation(leaf, trans->transid);
2260 btrfs_set_header_owner(leaf, objectid);
2261
2262 write_extent_buffer(leaf, root->fs_info->fsid,
2263 (unsigned long)btrfs_header_fsid(leaf),
2264 BTRFS_FSID_SIZE);
2265 btrfs_mark_buffer_dirty(leaf);
2266
2267 inode_item = &root_item.inode;
2268 memset(inode_item, 0, sizeof(*inode_item));
2269 inode_item->generation = cpu_to_le64(1);
2270 inode_item->size = cpu_to_le64(3);
2271 inode_item->nlink = cpu_to_le32(1);
2272 inode_item->nblocks = cpu_to_le64(1);
2273 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
2274
2275 btrfs_set_root_bytenr(&root_item, leaf->start);
2276 btrfs_set_root_level(&root_item, 0);
2277 btrfs_set_root_refs(&root_item, 1);
2278 btrfs_set_root_used(&root_item, 0);
2279
2280 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
2281 root_item.drop_level = 0;
2282
2283 free_extent_buffer(leaf);
2284 leaf = NULL;
2285
2286 btrfs_set_root_dirid(&root_item, new_dirid);
2287
2288 key.objectid = objectid;
2289 key.offset = 1;
2290 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
2291 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
2292 &root_item);
2293 if (ret)
2294 goto fail;
2295
2296 /*
2297 * insert the directory item
2298 */
2299 key.offset = (u64)-1;
2300 dir = root->fs_info->sb->s_root->d_inode;
2301 ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
2302 name, namelen, dir->i_ino, &key,
2303 BTRFS_FT_DIR);
2304 if (ret)
2305 goto fail;
2306
2307 ret = btrfs_insert_inode_ref(trans, root->fs_info->tree_root,
2308 name, namelen, objectid,
2309 root->fs_info->sb->s_root->d_inode->i_ino);
2310 if (ret)
2311 goto fail;
2312
2313 ret = btrfs_commit_transaction(trans, root);
2314 if (ret)
2315 goto fail_commit;
2316
2317 new_root = btrfs_read_fs_root(root->fs_info, &key, name, namelen);
2318 BUG_ON(!new_root);
2319
2320 trans = btrfs_start_transaction(new_root, 1);
2321 BUG_ON(!trans);
2322
2323 inode = btrfs_new_inode(trans, new_root, new_dirid,
2324 BTRFS_I(dir)->block_group, S_IFDIR | 0700);
2325 if (IS_ERR(inode))
2326 goto fail;
2327 inode->i_op = &btrfs_dir_inode_operations;
2328 inode->i_fop = &btrfs_dir_file_operations;
2329 new_root->inode = inode;
2330
2331 ret = btrfs_insert_inode_ref(trans, new_root, "..", 2, new_dirid,
2332 new_dirid);
2333 inode->i_nlink = 1;
2334 inode->i_size = 0;
2335 ret = btrfs_update_inode(trans, new_root, inode);
2336 if (ret)
2337 goto fail;
2338 fail:
2339 nr = trans->blocks_used;
2340 err = btrfs_commit_transaction(trans, new_root);
2341 if (err && !ret)
2342 ret = err;
2343 fail_commit:
2344 mutex_unlock(&root->fs_info->fs_mutex);
2345 btrfs_btree_balance_dirty(root, nr);
2346 btrfs_throttle(root);
2347 return ret;
2348 }
2349
2350 static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
2351 {
2352 struct btrfs_pending_snapshot *pending_snapshot;
2353 struct btrfs_trans_handle *trans;
2354 int ret;
2355 int err;
2356 unsigned long nr = 0;
2357
2358 if (!root->ref_cows)
2359 return -EINVAL;
2360
2361 mutex_lock(&root->fs_info->fs_mutex);
2362 ret = btrfs_check_free_space(root, 1, 0);
2363 if (ret)
2364 goto fail_unlock;
2365
2366 pending_snapshot = kmalloc(sizeof(*pending_snapshot), GFP_NOFS);
2367 if (!pending_snapshot) {
2368 ret = -ENOMEM;
2369 goto fail_unlock;
2370 }
2371 pending_snapshot->name = kmalloc(namelen + 1, GFP_NOFS);
2372 if (!pending_snapshot->name) {
2373 ret = -ENOMEM;
2374 kfree(pending_snapshot);
2375 goto fail_unlock;
2376 }
2377 memcpy(pending_snapshot->name, name, namelen);
2378 pending_snapshot->name[namelen] = '\0';
2379 trans = btrfs_start_transaction(root, 1);
2380 BUG_ON(!trans);
2381 pending_snapshot->root = root;
2382 list_add(&pending_snapshot->list,
2383 &trans->transaction->pending_snapshots);
2384 ret = btrfs_update_inode(trans, root, root->inode);
2385 err = btrfs_commit_transaction(trans, root);
2386
2387 fail_unlock:
2388 mutex_unlock(&root->fs_info->fs_mutex);
2389 btrfs_btree_balance_dirty(root, nr);
2390 btrfs_throttle(root);
2391 return ret;
2392 }
2393
2394 unsigned long btrfs_force_ra(struct address_space *mapping,
2395 struct file_ra_state *ra, struct file *file,
2396 pgoff_t offset, pgoff_t last_index)
2397 {
2398 pgoff_t req_size;
2399
2400 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
2401 req_size = last_index - offset + 1;
2402 offset = page_cache_readahead(mapping, ra, file, offset, req_size);
2403 return offset;
2404 #else
2405 req_size = min(last_index - offset + 1, (pgoff_t)128);
2406 page_cache_sync_readahead(mapping, ra, file, offset, req_size);
2407 return offset + req_size;
2408 #endif
2409 }
2410
2411 int btrfs_defrag_file(struct file *file) {
2412 struct inode *inode = fdentry(file)->d_inode;
2413 struct btrfs_root *root = BTRFS_I(inode)->root;
2414 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2415 struct page *page;
2416 unsigned long last_index;
2417 unsigned long ra_index = 0;
2418 u64 page_start;
2419 u64 page_end;
2420 u64 delalloc_start;
2421 u64 existing_delalloc;
2422 unsigned long i;
2423 int ret;
2424
2425 mutex_lock(&root->fs_info->fs_mutex);
2426 ret = btrfs_check_free_space(root, inode->i_size, 0);
2427 mutex_unlock(&root->fs_info->fs_mutex);
2428 if (ret)
2429 return -ENOSPC;
2430
2431 mutex_lock(&inode->i_mutex);
2432 last_index = inode->i_size >> PAGE_CACHE_SHIFT;
2433 for (i = 0; i <= last_index; i++) {
2434 if (i == ra_index) {
2435 ra_index = btrfs_force_ra(inode->i_mapping,
2436 &file->f_ra,
2437 file, ra_index, last_index);
2438 }
2439 page = grab_cache_page(inode->i_mapping, i);
2440 if (!page)
2441 goto out_unlock;
2442 if (!PageUptodate(page)) {
2443 btrfs_readpage(NULL, page);
2444 lock_page(page);
2445 if (!PageUptodate(page)) {
2446 unlock_page(page);
2447 page_cache_release(page);
2448 goto out_unlock;
2449 }
2450 }
2451 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2452 page_end = page_start + PAGE_CACHE_SIZE - 1;
2453
2454 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
2455 delalloc_start = page_start;
2456 existing_delalloc =
2457 count_range_bits(&BTRFS_I(inode)->io_tree,
2458 &delalloc_start, page_end,
2459 PAGE_CACHE_SIZE, EXTENT_DELALLOC);
2460 set_extent_delalloc(io_tree, page_start,
2461 page_end, GFP_NOFS);
2462
2463 spin_lock(&root->fs_info->delalloc_lock);
2464 root->fs_info->delalloc_bytes += PAGE_CACHE_SIZE -
2465 existing_delalloc;
2466 spin_unlock(&root->fs_info->delalloc_lock);
2467
2468 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
2469 set_page_dirty(page);
2470 unlock_page(page);
2471 page_cache_release(page);
2472 balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);
2473 }
2474
2475 out_unlock:
2476 mutex_unlock(&inode->i_mutex);
2477 return 0;
2478 }
2479
2480 static int btrfs_ioctl_resize(struct btrfs_root *root, void __user *arg)
2481 {
2482 u64 new_size;
2483 u64 old_size;
2484 struct btrfs_ioctl_vol_args *vol_args;
2485 struct btrfs_trans_handle *trans;
2486 char *sizestr;
2487 int ret = 0;
2488 int namelen;
2489 int mod = 0;
2490
2491 vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS);
2492
2493 if (!vol_args)
2494 return -ENOMEM;
2495
2496 if (copy_from_user(vol_args, arg, sizeof(*vol_args))) {
2497 ret = -EFAULT;
2498 goto out;
2499 }
2500 namelen = strlen(vol_args->name);
2501 if (namelen > BTRFS_VOL_NAME_MAX) {
2502 ret = -EINVAL;
2503 goto out;
2504 }
2505
2506 sizestr = vol_args->name;
2507 if (!strcmp(sizestr, "max"))
2508 new_size = root->fs_info->sb->s_bdev->bd_inode->i_size;
2509 else {
2510 if (sizestr[0] == '-') {
2511 mod = -1;
2512 sizestr++;
2513 } else if (sizestr[0] == '+') {
2514 mod = 1;
2515 sizestr++;
2516 }
2517 new_size = btrfs_parse_size(sizestr);
2518 if (new_size == 0) {
2519 ret = -EINVAL;
2520 goto out;
2521 }
2522 }
2523
2524 mutex_lock(&root->fs_info->fs_mutex);
2525 old_size = btrfs_super_total_bytes(&root->fs_info->super_copy);
2526
2527 if (mod < 0) {
2528 if (new_size > old_size) {
2529 ret = -EINVAL;
2530 goto out_unlock;
2531 }
2532 new_size = old_size - new_size;
2533 } else if (mod > 0) {
2534 new_size = old_size + new_size;
2535 }
2536
2537 if (new_size < 256 * 1024 * 1024) {
2538 ret = -EINVAL;
2539 goto out_unlock;
2540 }
2541 if (new_size > root->fs_info->sb->s_bdev->bd_inode->i_size) {
2542 ret = -EFBIG;
2543 goto out_unlock;
2544 }
2545
2546 do_div(new_size, root->sectorsize);
2547 new_size *= root->sectorsize;
2548
2549 printk("new size is %Lu\n", new_size);
2550 if (new_size > old_size) {
2551 trans = btrfs_start_transaction(root, 1);
2552 ret = btrfs_grow_extent_tree(trans, root, new_size);
2553 btrfs_commit_transaction(trans, root);
2554 } else {
2555 ret = btrfs_shrink_extent_tree(root, new_size);
2556 }
2557
2558 out_unlock:
2559 mutex_unlock(&root->fs_info->fs_mutex);
2560 out:
2561 kfree(vol_args);
2562 return ret;
2563 }
2564
2565 static int noinline btrfs_ioctl_snap_create(struct btrfs_root *root,
2566 void __user *arg)
2567 {
2568 struct btrfs_ioctl_vol_args *vol_args;
2569 struct btrfs_dir_item *di;
2570 struct btrfs_path *path;
2571 u64 root_dirid;
2572 int namelen;
2573 int ret;
2574
2575 vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS);
2576
2577 if (!vol_args)
2578 return -ENOMEM;
2579
2580 if (copy_from_user(vol_args, arg, sizeof(*vol_args))) {
2581 ret = -EFAULT;
2582 goto out;
2583 }
2584
2585 namelen = strlen(vol_args->name);
2586 if (namelen > BTRFS_VOL_NAME_MAX) {
2587 ret = -EINVAL;
2588 goto out;
2589 }
2590 if (strchr(vol_args->name, '/')) {
2591 ret = -EINVAL;
2592 goto out;
2593 }
2594
2595 path = btrfs_alloc_path();
2596 if (!path) {
2597 ret = -ENOMEM;
2598 goto out;
2599 }
2600
2601 root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
2602 mutex_lock(&root->fs_info->fs_mutex);
2603 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
2604 path, root_dirid,
2605 vol_args->name, namelen, 0);
2606 mutex_unlock(&root->fs_info->fs_mutex);
2607 btrfs_free_path(path);
2608
2609 if (di && !IS_ERR(di)) {
2610 ret = -EEXIST;
2611 goto out;
2612 }
2613
2614 if (IS_ERR(di)) {
2615 ret = PTR_ERR(di);
2616 goto out;
2617 }
2618
2619 if (root == root->fs_info->tree_root)
2620 ret = create_subvol(root, vol_args->name, namelen);
2621 else
2622 ret = create_snapshot(root, vol_args->name, namelen);
2623 out:
2624 kfree(vol_args);
2625 return ret;
2626 }
2627
2628 static int btrfs_ioctl_defrag(struct file *file)
2629 {
2630 struct inode *inode = fdentry(file)->d_inode;
2631 struct btrfs_root *root = BTRFS_I(inode)->root;
2632
2633 switch (inode->i_mode & S_IFMT) {
2634 case S_IFDIR:
2635 mutex_lock(&root->fs_info->fs_mutex);
2636 btrfs_defrag_root(root, 0);
2637 btrfs_defrag_root(root->fs_info->extent_root, 0);
2638 mutex_unlock(&root->fs_info->fs_mutex);
2639 break;
2640 case S_IFREG:
2641 btrfs_defrag_file(file);
2642 break;
2643 }
2644
2645 return 0;
2646 }
2647
2648 long btrfs_ioctl(struct file *file, unsigned int
2649 cmd, unsigned long arg)
2650 {
2651 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2652
2653 switch (cmd) {
2654 case BTRFS_IOC_SNAP_CREATE:
2655 return btrfs_ioctl_snap_create(root, (void __user *)arg);
2656 case BTRFS_IOC_DEFRAG:
2657 return btrfs_ioctl_defrag(file);
2658 case BTRFS_IOC_RESIZE:
2659 return btrfs_ioctl_resize(root, (void __user *)arg);
2660 }
2661
2662 return -ENOTTY;
2663 }
2664
2665 /*
2666 * Called inside transaction, so use GFP_NOFS
2667 */
2668 struct inode *btrfs_alloc_inode(struct super_block *sb)
2669 {
2670 struct btrfs_inode *ei;
2671
2672 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
2673 if (!ei)
2674 return NULL;
2675 ei->last_trans = 0;
2676 ei->ordered_trans = 0;
2677 return &ei->vfs_inode;
2678 }
2679
2680 void btrfs_destroy_inode(struct inode *inode)
2681 {
2682 WARN_ON(!list_empty(&inode->i_dentry));
2683 WARN_ON(inode->i_data.nrpages);
2684
2685 btrfs_drop_extent_cache(inode, 0, (u64)-1);
2686 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
2687 }
2688
2689 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
2690 static void init_once(struct kmem_cache * cachep, void *foo)
2691 #else
2692 static void init_once(void * foo, struct kmem_cache * cachep,
2693 unsigned long flags)
2694 #endif
2695 {
2696 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
2697
2698 inode_init_once(&ei->vfs_inode);
2699 }
2700
2701 void btrfs_destroy_cachep(void)
2702 {
2703 if (btrfs_inode_cachep)
2704 kmem_cache_destroy(btrfs_inode_cachep);
2705 if (btrfs_trans_handle_cachep)
2706 kmem_cache_destroy(btrfs_trans_handle_cachep);
2707 if (btrfs_transaction_cachep)
2708 kmem_cache_destroy(btrfs_transaction_cachep);
2709 if (btrfs_bit_radix_cachep)
2710 kmem_cache_destroy(btrfs_bit_radix_cachep);
2711 if (btrfs_path_cachep)
2712 kmem_cache_destroy(btrfs_path_cachep);
2713 }
2714
2715 struct kmem_cache *btrfs_cache_create(const char *name, size_t size,
2716 unsigned long extra_flags,
2717 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
2718 void (*ctor)(struct kmem_cache *, void *)
2719 #else
2720 void (*ctor)(void *, struct kmem_cache *,
2721 unsigned long)
2722 #endif
2723 )
2724 {
2725 return kmem_cache_create(name, size, 0, (SLAB_RECLAIM_ACCOUNT |
2726 SLAB_MEM_SPREAD | extra_flags), ctor
2727 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
2728 ,NULL
2729 #endif
2730 );
2731 }
2732
2733 int btrfs_init_cachep(void)
2734 {
2735 btrfs_inode_cachep = btrfs_cache_create("btrfs_inode_cache",
2736 sizeof(struct btrfs_inode),
2737 0, init_once);
2738 if (!btrfs_inode_cachep)
2739 goto fail;
2740 btrfs_trans_handle_cachep =
2741 btrfs_cache_create("btrfs_trans_handle_cache",
2742 sizeof(struct btrfs_trans_handle),
2743 0, NULL);
2744 if (!btrfs_trans_handle_cachep)
2745 goto fail;
2746 btrfs_transaction_cachep = btrfs_cache_create("btrfs_transaction_cache",
2747 sizeof(struct btrfs_transaction),
2748 0, NULL);
2749 if (!btrfs_transaction_cachep)
2750 goto fail;
2751 btrfs_path_cachep = btrfs_cache_create("btrfs_path_cache",
2752 sizeof(struct btrfs_path),
2753 0, NULL);
2754 if (!btrfs_path_cachep)
2755 goto fail;
2756 btrfs_bit_radix_cachep = btrfs_cache_create("btrfs_radix", 256,
2757 SLAB_DESTROY_BY_RCU, NULL);
2758 if (!btrfs_bit_radix_cachep)
2759 goto fail;
2760 return 0;
2761 fail:
2762 btrfs_destroy_cachep();
2763 return -ENOMEM;
2764 }
2765
2766 static int btrfs_getattr(struct vfsmount *mnt,
2767 struct dentry *dentry, struct kstat *stat)
2768 {
2769 struct inode *inode = dentry->d_inode;
2770 generic_fillattr(inode, stat);
2771 stat->blksize = PAGE_CACHE_SIZE;
2772 return 0;
2773 }
2774
2775 static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
2776 struct inode * new_dir,struct dentry *new_dentry)
2777 {
2778 struct btrfs_trans_handle *trans;
2779 struct btrfs_root *root = BTRFS_I(old_dir)->root;
2780 struct inode *new_inode = new_dentry->d_inode;
2781 struct inode *old_inode = old_dentry->d_inode;
2782 struct timespec ctime = CURRENT_TIME;
2783 struct btrfs_path *path;
2784 int ret;
2785
2786 if (S_ISDIR(old_inode->i_mode) && new_inode &&
2787 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
2788 return -ENOTEMPTY;
2789 }
2790
2791 mutex_lock(&root->fs_info->fs_mutex);
2792 ret = btrfs_check_free_space(root, 1, 0);
2793 if (ret)
2794 goto out_unlock;
2795
2796 trans = btrfs_start_transaction(root, 1);
2797
2798 btrfs_set_trans_block_group(trans, new_dir);
2799 path = btrfs_alloc_path();
2800 if (!path) {
2801 ret = -ENOMEM;
2802 goto out_fail;
2803 }
2804
2805 old_dentry->d_inode->i_nlink++;
2806 old_dir->i_ctime = old_dir->i_mtime = ctime;
2807 new_dir->i_ctime = new_dir->i_mtime = ctime;
2808 old_inode->i_ctime = ctime;
2809
2810 ret = btrfs_unlink_trans(trans, root, old_dir, old_dentry);
2811 if (ret)
2812 goto out_fail;
2813
2814 if (new_inode) {
2815 new_inode->i_ctime = CURRENT_TIME;
2816 ret = btrfs_unlink_trans(trans, root, new_dir, new_dentry);
2817 if (ret)
2818 goto out_fail;
2819 }
2820 ret = btrfs_add_link(trans, new_dentry, old_inode);
2821 if (ret)
2822 goto out_fail;
2823
2824 out_fail:
2825 btrfs_free_path(path);
2826 btrfs_end_transaction(trans, root);
2827 out_unlock:
2828 mutex_unlock(&root->fs_info->fs_mutex);
2829 return ret;
2830 }
2831
2832 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
2833 const char *symname)
2834 {
2835 struct btrfs_trans_handle *trans;
2836 struct btrfs_root *root = BTRFS_I(dir)->root;
2837 struct btrfs_path *path;
2838 struct btrfs_key key;
2839 struct inode *inode = NULL;
2840 int err;
2841 int drop_inode = 0;
2842 u64 objectid;
2843 int name_len;
2844 int datasize;
2845 unsigned long ptr;
2846 struct btrfs_file_extent_item *ei;
2847 struct extent_buffer *leaf;
2848 unsigned long nr = 0;
2849
2850 name_len = strlen(symname) + 1;
2851 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
2852 return -ENAMETOOLONG;
2853
2854 mutex_lock(&root->fs_info->fs_mutex);
2855 err = btrfs_check_free_space(root, 1, 0);
2856 if (err)
2857 goto out_fail;
2858
2859 trans = btrfs_start_transaction(root, 1);
2860 btrfs_set_trans_block_group(trans, dir);
2861
2862 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2863 if (err) {
2864 err = -ENOSPC;
2865 goto out_unlock;
2866 }
2867
2868 inode = btrfs_new_inode(trans, root, objectid,
2869 BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO);
2870 err = PTR_ERR(inode);
2871 if (IS_ERR(inode))
2872 goto out_unlock;
2873
2874 btrfs_set_trans_block_group(trans, inode);
2875 err = btrfs_add_nondir(trans, dentry, inode);
2876 if (err)
2877 drop_inode = 1;
2878 else {
2879 inode->i_mapping->a_ops = &btrfs_aops;
2880 inode->i_fop = &btrfs_file_operations;
2881 inode->i_op = &btrfs_file_inode_operations;
2882 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
2883 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
2884 inode->i_mapping, GFP_NOFS);
2885 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
2886 }
2887 dir->i_sb->s_dirt = 1;
2888 btrfs_update_inode_block_group(trans, inode);
2889 btrfs_update_inode_block_group(trans, dir);
2890 if (drop_inode)
2891 goto out_unlock;
2892
2893 path = btrfs_alloc_path();
2894 BUG_ON(!path);
2895 key.objectid = inode->i_ino;
2896 key.offset = 0;
2897 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
2898 datasize = btrfs_file_extent_calc_inline_size(name_len);
2899 err = btrfs_insert_empty_item(trans, root, path, &key,
2900 datasize);
2901 if (err) {
2902 drop_inode = 1;
2903 goto out_unlock;
2904 }
2905 leaf = path->nodes[0];
2906 ei = btrfs_item_ptr(leaf, path->slots[0],
2907 struct btrfs_file_extent_item);
2908 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
2909 btrfs_set_file_extent_type(leaf, ei,
2910 BTRFS_FILE_EXTENT_INLINE);
2911 ptr = btrfs_file_extent_inline_start(ei);
2912 write_extent_buffer(leaf, symname, ptr, name_len);
2913 btrfs_mark_buffer_dirty(leaf);
2914 btrfs_free_path(path);
2915
2916 inode->i_op = &btrfs_symlink_inode_operations;
2917 inode->i_mapping->a_ops = &btrfs_symlink_aops;
2918 inode->i_size = name_len - 1;
2919 err = btrfs_update_inode(trans, root, inode);
2920 if (err)
2921 drop_inode = 1;
2922
2923 out_unlock:
2924 nr = trans->blocks_used;
2925 btrfs_end_transaction(trans, root);
2926 out_fail:
2927 mutex_unlock(&root->fs_info->fs_mutex);
2928 if (drop_inode) {
2929 inode_dec_link_count(inode);
2930 iput(inode);
2931 }
2932 btrfs_btree_balance_dirty(root, nr);
2933 btrfs_throttle(root);
2934 return err;
2935 }
2936 static int btrfs_permission(struct inode *inode, int mask,
2937 struct nameidata *nd)
2938 {
2939 if (btrfs_test_flag(inode, READONLY) && (mask & MAY_WRITE))
2940 return -EACCES;
2941 return generic_permission(inode, mask, NULL);
2942 }
2943
2944 static struct inode_operations btrfs_dir_inode_operations = {
2945 .lookup = btrfs_lookup,
2946 .create = btrfs_create,
2947 .unlink = btrfs_unlink,
2948 .link = btrfs_link,
2949 .mkdir = btrfs_mkdir,
2950 .rmdir = btrfs_rmdir,
2951 .rename = btrfs_rename,
2952 .symlink = btrfs_symlink,
2953 .setattr = btrfs_setattr,
2954 .mknod = btrfs_mknod,
2955 .setxattr = generic_setxattr,
2956 .getxattr = generic_getxattr,
2957 .listxattr = btrfs_listxattr,
2958 .removexattr = generic_removexattr,
2959 .permission = btrfs_permission,
2960 };
2961 static struct inode_operations btrfs_dir_ro_inode_operations = {
2962 .lookup = btrfs_lookup,
2963 .permission = btrfs_permission,
2964 };
2965 static struct file_operations btrfs_dir_file_operations = {
2966 .llseek = generic_file_llseek,
2967 .read = generic_read_dir,
2968 .readdir = btrfs_readdir,
2969 .unlocked_ioctl = btrfs_ioctl,
2970 #ifdef CONFIG_COMPAT
2971 .compat_ioctl = btrfs_ioctl,
2972 #endif
2973 };
2974
2975 static struct extent_io_ops btrfs_extent_io_ops = {
2976 .fill_delalloc = run_delalloc_range,
2977 .writepage_io_hook = btrfs_writepage_io_hook,
2978 .readpage_io_hook = btrfs_readpage_io_hook,
2979 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
2980 };
2981
2982 static struct address_space_operations btrfs_aops = {
2983 .readpage = btrfs_readpage,
2984 .writepage = btrfs_writepage,
2985 .writepages = btrfs_writepages,
2986 .readpages = btrfs_readpages,
2987 .sync_page = block_sync_page,
2988 .bmap = btrfs_bmap,
2989 .invalidatepage = btrfs_invalidatepage,
2990 .releasepage = btrfs_releasepage,
2991 .set_page_dirty = __set_page_dirty_nobuffers,
2992 };
2993
2994 static struct address_space_operations btrfs_symlink_aops = {
2995 .readpage = btrfs_readpage,
2996 .writepage = btrfs_writepage,
2997 .invalidatepage = btrfs_invalidatepage,
2998 .releasepage = btrfs_releasepage,
2999 };
3000
3001 static struct inode_operations btrfs_file_inode_operations = {
3002 .truncate = btrfs_truncate,
3003 .getattr = btrfs_getattr,
3004 .setattr = btrfs_setattr,
3005 .setxattr = generic_setxattr,
3006 .getxattr = generic_getxattr,
3007 .listxattr = btrfs_listxattr,
3008 .removexattr = generic_removexattr,
3009 .permission = btrfs_permission,
3010 };
3011 static struct inode_operations btrfs_special_inode_operations = {
3012 .getattr = btrfs_getattr,
3013 .setattr = btrfs_setattr,
3014 .permission = btrfs_permission,
3015 };
3016 static struct inode_operations btrfs_symlink_inode_operations = {
3017 .readlink = generic_readlink,
3018 .follow_link = page_follow_link_light,
3019 .put_link = page_put_link,
3020 .permission = btrfs_permission,
3021 };
Linux kernel - Deliverables
This page took 0.127208 seconds and 6 git commands to generate.