projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Btrfs: Add inode item and backref in one insert, reducing cpu usage
[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 const char *name, int name_len,
1504 u64 ref_objectid,
1505 u64 objectid,
1506 struct btrfs_block_group_cache *group,
1507 int mode)
1508 {
1509 struct inode *inode;
1510 struct btrfs_inode_item *inode_item;
1511 struct btrfs_key *location;
1512 struct btrfs_path *path;
1513 struct btrfs_inode_ref *ref;
1514 struct btrfs_key key[2];
1515 u32 sizes[2];
1516 unsigned long ptr;
1517 int ret;
1518 int owner;
1519
1520 path = btrfs_alloc_path();
1521 BUG_ON(!path);
1522
1523 inode = new_inode(root->fs_info->sb);
1524 if (!inode)
1525 return ERR_PTR(-ENOMEM);
1526
1527 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
1528 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
1529 inode->i_mapping, GFP_NOFS);
1530 BTRFS_I(inode)->root = root;
1531
1532 if (mode & S_IFDIR)
1533 owner = 0;
1534 else
1535 owner = 1;
1536 group = btrfs_find_block_group(root, group, 0, 0, owner);
1537 BTRFS_I(inode)->block_group = group;
1538 BTRFS_I(inode)->flags = 0;
1539
1540 key[0].objectid = objectid;
1541 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
1542 key[0].offset = 0;
1543
1544 key[1].objectid = objectid;
1545 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
1546 key[1].offset = ref_objectid;
1547
1548 sizes[0] = sizeof(struct btrfs_inode_item);
1549 sizes[1] = name_len + sizeof(*ref);
1550
1551 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
1552 if (ret != 0)
1553 goto fail;
1554
1555 if (objectid > root->highest_inode)
1556 root->highest_inode = objectid;
1557
1558 inode->i_uid = current->fsuid;
1559 inode->i_gid = current->fsgid;
1560 inode->i_mode = mode;
1561 inode->i_ino = objectid;
1562 inode->i_blocks = 0;
1563 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1564 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
1565 struct btrfs_inode_item);
1566 fill_inode_item(path->nodes[0], inode_item, inode);
1567
1568 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
1569 struct btrfs_inode_ref);
1570 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
1571 ptr = (unsigned long)(ref + 1);
1572 write_extent_buffer(path->nodes[0], name, ptr, name_len);
1573
1574 btrfs_mark_buffer_dirty(path->nodes[0]);
1575 btrfs_free_path(path);
1576
1577 location = &BTRFS_I(inode)->location;
1578 location->objectid = objectid;
1579 location->offset = 0;
1580 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
1581
1582 insert_inode_hash(inode);
1583 return inode;
1584 fail:
1585 btrfs_free_path(path);
1586 return ERR_PTR(ret);
1587 }
1588
1589 static inline u8 btrfs_inode_type(struct inode *inode)
1590 {
1591 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
1592 }
1593
1594 static int btrfs_add_link(struct btrfs_trans_handle *trans,
1595 struct dentry *dentry, struct inode *inode,
1596 int add_backref)
1597 {
1598 int ret;
1599 struct btrfs_key key;
1600 struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
1601 struct inode *parent_inode;
1602
1603 key.objectid = inode->i_ino;
1604 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
1605 key.offset = 0;
1606
1607 ret = btrfs_insert_dir_item(trans, root,
1608 dentry->d_name.name, dentry->d_name.len,
1609 dentry->d_parent->d_inode->i_ino,
1610 &key, btrfs_inode_type(inode));
1611 if (ret == 0) {
1612 if (add_backref) {
1613 ret = btrfs_insert_inode_ref(trans, root,
1614 dentry->d_name.name,
1615 dentry->d_name.len,
1616 inode->i_ino,
1617 dentry->d_parent->d_inode->i_ino);
1618 }
1619 parent_inode = dentry->d_parent->d_inode;
1620 parent_inode->i_size += dentry->d_name.len * 2;
1621 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
1622 ret = btrfs_update_inode(trans, root,
1623 dentry->d_parent->d_inode);
1624 }
1625 return ret;
1626 }
1627
1628 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
1629 struct dentry *dentry, struct inode *inode,
1630 int backref)
1631 {
1632 int err = btrfs_add_link(trans, dentry, inode, backref);
1633 if (!err) {
1634 d_instantiate(dentry, inode);
1635 return 0;
1636 }
1637 if (err > 0)
1638 err = -EEXIST;
1639 return err;
1640 }
1641
1642 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
1643 int mode, dev_t rdev)
1644 {
1645 struct btrfs_trans_handle *trans;
1646 struct btrfs_root *root = BTRFS_I(dir)->root;
1647 struct inode *inode = NULL;
1648 int err;
1649 int drop_inode = 0;
1650 u64 objectid;
1651 unsigned long nr = 0;
1652
1653 if (!new_valid_dev(rdev))
1654 return -EINVAL;
1655
1656 mutex_lock(&root->fs_info->fs_mutex);
1657 err = btrfs_check_free_space(root, 1, 0);
1658 if (err)
1659 goto fail;
1660
1661 trans = btrfs_start_transaction(root, 1);
1662 btrfs_set_trans_block_group(trans, dir);
1663
1664 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1665 if (err) {
1666 err = -ENOSPC;
1667 goto out_unlock;
1668 }
1669
1670 inode = btrfs_new_inode(trans, root, dentry->d_name.name,
1671 dentry->d_name.len,
1672 dentry->d_parent->d_inode->i_ino, objectid,
1673 BTRFS_I(dir)->block_group, mode);
1674 err = PTR_ERR(inode);
1675 if (IS_ERR(inode))
1676 goto out_unlock;
1677
1678 btrfs_set_trans_block_group(trans, inode);
1679 err = btrfs_add_nondir(trans, dentry, inode, 0);
1680 if (err)
1681 drop_inode = 1;
1682 else {
1683 inode->i_op = &btrfs_special_inode_operations;
1684 init_special_inode(inode, inode->i_mode, rdev);
1685 btrfs_update_inode(trans, root, inode);
1686 }
1687 dir->i_sb->s_dirt = 1;
1688 btrfs_update_inode_block_group(trans, inode);
1689 btrfs_update_inode_block_group(trans, dir);
1690 out_unlock:
1691 nr = trans->blocks_used;
1692 btrfs_end_transaction(trans, root);
1693 fail:
1694 mutex_unlock(&root->fs_info->fs_mutex);
1695
1696 if (drop_inode) {
1697 inode_dec_link_count(inode);
1698 iput(inode);
1699 }
1700 btrfs_btree_balance_dirty(root, nr);
1701 btrfs_throttle(root);
1702 return err;
1703 }
1704
1705 static int btrfs_create(struct inode *dir, struct dentry *dentry,
1706 int mode, struct nameidata *nd)
1707 {
1708 struct btrfs_trans_handle *trans;
1709 struct btrfs_root *root = BTRFS_I(dir)->root;
1710 struct inode *inode = NULL;
1711 int err;
1712 int drop_inode = 0;
1713 unsigned long nr = 0;
1714 u64 objectid;
1715
1716 mutex_lock(&root->fs_info->fs_mutex);
1717 err = btrfs_check_free_space(root, 1, 0);
1718 if (err)
1719 goto fail;
1720 trans = btrfs_start_transaction(root, 1);
1721 btrfs_set_trans_block_group(trans, dir);
1722
1723 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1724 if (err) {
1725 err = -ENOSPC;
1726 goto out_unlock;
1727 }
1728
1729 inode = btrfs_new_inode(trans, root, dentry->d_name.name,
1730 dentry->d_name.len,
1731 dentry->d_parent->d_inode->i_ino,
1732 objectid, BTRFS_I(dir)->block_group, mode);
1733 err = PTR_ERR(inode);
1734 if (IS_ERR(inode))
1735 goto out_unlock;
1736
1737 btrfs_set_trans_block_group(trans, inode);
1738 err = btrfs_add_nondir(trans, dentry, inode, 0);
1739 if (err)
1740 drop_inode = 1;
1741 else {
1742 inode->i_mapping->a_ops = &btrfs_aops;
1743 inode->i_fop = &btrfs_file_operations;
1744 inode->i_op = &btrfs_file_inode_operations;
1745 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
1746 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
1747 inode->i_mapping, GFP_NOFS);
1748 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
1749 }
1750 dir->i_sb->s_dirt = 1;
1751 btrfs_update_inode_block_group(trans, inode);
1752 btrfs_update_inode_block_group(trans, dir);
1753 out_unlock:
1754 nr = trans->blocks_used;
1755 btrfs_end_transaction(trans, root);
1756 fail:
1757 mutex_unlock(&root->fs_info->fs_mutex);
1758
1759 if (drop_inode) {
1760 inode_dec_link_count(inode);
1761 iput(inode);
1762 }
1763 btrfs_btree_balance_dirty(root, nr);
1764 btrfs_throttle(root);
1765 return err;
1766 }
1767
1768 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
1769 struct dentry *dentry)
1770 {
1771 struct btrfs_trans_handle *trans;
1772 struct btrfs_root *root = BTRFS_I(dir)->root;
1773 struct inode *inode = old_dentry->d_inode;
1774 unsigned long nr = 0;
1775 int err;
1776 int drop_inode = 0;
1777
1778 if (inode->i_nlink == 0)
1779 return -ENOENT;
1780
1781 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
1782 inode->i_nlink++;
1783 #else
1784 inc_nlink(inode);
1785 #endif
1786 mutex_lock(&root->fs_info->fs_mutex);
1787 err = btrfs_check_free_space(root, 1, 0);
1788 if (err)
1789 goto fail;
1790 trans = btrfs_start_transaction(root, 1);
1791
1792 btrfs_set_trans_block_group(trans, dir);
1793 atomic_inc(&inode->i_count);
1794 err = btrfs_add_nondir(trans, dentry, inode, 1);
1795
1796 if (err)
1797 drop_inode = 1;
1798
1799 dir->i_sb->s_dirt = 1;
1800 btrfs_update_inode_block_group(trans, dir);
1801 err = btrfs_update_inode(trans, root, inode);
1802
1803 if (err)
1804 drop_inode = 1;
1805
1806 nr = trans->blocks_used;
1807 btrfs_end_transaction(trans, root);
1808 fail:
1809 mutex_unlock(&root->fs_info->fs_mutex);
1810
1811 if (drop_inode) {
1812 inode_dec_link_count(inode);
1813 iput(inode);
1814 }
1815 btrfs_btree_balance_dirty(root, nr);
1816 btrfs_throttle(root);
1817 return err;
1818 }
1819
1820 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
1821 {
1822 struct inode *inode;
1823 struct btrfs_trans_handle *trans;
1824 struct btrfs_root *root = BTRFS_I(dir)->root;
1825 int err = 0;
1826 int drop_on_err = 0;
1827 u64 objectid;
1828 unsigned long nr = 1;
1829
1830 mutex_lock(&root->fs_info->fs_mutex);
1831 err = btrfs_check_free_space(root, 1, 0);
1832 if (err)
1833 goto out_unlock;
1834
1835 trans = btrfs_start_transaction(root, 1);
1836 btrfs_set_trans_block_group(trans, dir);
1837
1838 if (IS_ERR(trans)) {
1839 err = PTR_ERR(trans);
1840 goto out_unlock;
1841 }
1842
1843 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
1844 if (err) {
1845 err = -ENOSPC;
1846 goto out_unlock;
1847 }
1848
1849 inode = btrfs_new_inode(trans, root, dentry->d_name.name,
1850 dentry->d_name.len,
1851 dentry->d_parent->d_inode->i_ino, objectid,
1852 BTRFS_I(dir)->block_group, S_IFDIR | mode);
1853 if (IS_ERR(inode)) {
1854 err = PTR_ERR(inode);
1855 goto out_fail;
1856 }
1857
1858 drop_on_err = 1;
1859 inode->i_op = &btrfs_dir_inode_operations;
1860 inode->i_fop = &btrfs_dir_file_operations;
1861 btrfs_set_trans_block_group(trans, inode);
1862
1863 inode->i_size = 0;
1864 err = btrfs_update_inode(trans, root, inode);
1865 if (err)
1866 goto out_fail;
1867
1868 err = btrfs_add_link(trans, dentry, inode, 0);
1869 if (err)
1870 goto out_fail;
1871
1872 d_instantiate(dentry, inode);
1873 drop_on_err = 0;
1874 dir->i_sb->s_dirt = 1;
1875 btrfs_update_inode_block_group(trans, inode);
1876 btrfs_update_inode_block_group(trans, dir);
1877
1878 out_fail:
1879 nr = trans->blocks_used;
1880 btrfs_end_transaction(trans, root);
1881
1882 out_unlock:
1883 mutex_unlock(&root->fs_info->fs_mutex);
1884 if (drop_on_err)
1885 iput(inode);
1886 btrfs_btree_balance_dirty(root, nr);
1887 btrfs_throttle(root);
1888 return err;
1889 }
1890
1891 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
1892 size_t pg_offset, u64 start, u64 len,
1893 int create)
1894 {
1895 int ret;
1896 int err = 0;
1897 u64 bytenr;
1898 u64 extent_start = 0;
1899 u64 extent_end = 0;
1900 u64 objectid = inode->i_ino;
1901 u32 found_type;
1902 struct btrfs_path *path;
1903 struct btrfs_root *root = BTRFS_I(inode)->root;
1904 struct btrfs_file_extent_item *item;
1905 struct extent_buffer *leaf;
1906 struct btrfs_key found_key;
1907 struct extent_map *em = NULL;
1908 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1909 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1910 struct btrfs_trans_handle *trans = NULL;
1911
1912 path = btrfs_alloc_path();
1913 BUG_ON(!path);
1914 mutex_lock(&root->fs_info->fs_mutex);
1915
1916 again:
1917 spin_lock(&em_tree->lock);
1918 em = lookup_extent_mapping(em_tree, start, len);
1919 spin_unlock(&em_tree->lock);
1920
1921 if (em) {
1922 if (em->start > start) {
1923 printk("get_extent lookup [%Lu %Lu] em [%Lu %Lu]\n",
1924 start, len, em->start, em->len);
1925 WARN_ON(1);
1926 }
1927 if (em->block_start == EXTENT_MAP_INLINE && page)
1928 free_extent_map(em);
1929 else
1930 goto out;
1931 }
1932 em = alloc_extent_map(GFP_NOFS);
1933 if (!em) {
1934 err = -ENOMEM;
1935 goto out;
1936 }
1937
1938 em->start = EXTENT_MAP_HOLE;
1939 em->len = (u64)-1;
1940 em->bdev = inode->i_sb->s_bdev;
1941 ret = btrfs_lookup_file_extent(trans, root, path,
1942 objectid, start, trans != NULL);
1943 if (ret < 0) {
1944 err = ret;
1945 goto out;
1946 }
1947
1948 if (ret != 0) {
1949 if (path->slots[0] == 0)
1950 goto not_found;
1951 path->slots[0]--;
1952 }
1953
1954 leaf = path->nodes[0];
1955 item = btrfs_item_ptr(leaf, path->slots[0],
1956 struct btrfs_file_extent_item);
1957 /* are we inside the extent that was found? */
1958 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1959 found_type = btrfs_key_type(&found_key);
1960 if (found_key.objectid != objectid ||
1961 found_type != BTRFS_EXTENT_DATA_KEY) {
1962 goto not_found;
1963 }
1964
1965 found_type = btrfs_file_extent_type(leaf, item);
1966 extent_start = found_key.offset;
1967 if (found_type == BTRFS_FILE_EXTENT_REG) {
1968 extent_end = extent_start +
1969 btrfs_file_extent_num_bytes(leaf, item);
1970 err = 0;
1971 if (start < extent_start || start >= extent_end) {
1972 em->start = start;
1973 if (start < extent_start) {
1974 if (start + len <= extent_start)
1975 goto not_found;
1976 em->len = extent_end - extent_start;
1977 } else {
1978 em->len = len;
1979 }
1980 goto not_found_em;
1981 }
1982 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
1983 if (bytenr == 0) {
1984 em->start = extent_start;
1985 em->len = extent_end - extent_start;
1986 em->block_start = EXTENT_MAP_HOLE;
1987 goto insert;
1988 }
1989 bytenr += btrfs_file_extent_offset(leaf, item);
1990 em->block_start = bytenr;
1991 em->start = extent_start;
1992 em->len = extent_end - extent_start;
1993 goto insert;
1994 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
1995 u64 page_start;
1996 unsigned long ptr;
1997 char *map;
1998 size_t size;
1999 size_t extent_offset;
2000 size_t copy_size;
2001
2002 size = btrfs_file_extent_inline_len(leaf, btrfs_item_nr(leaf,
2003 path->slots[0]));
2004 extent_end = (extent_start + size + root->sectorsize - 1) &
2005 ~((u64)root->sectorsize - 1);
2006 if (start < extent_start || start >= extent_end) {
2007 em->start = start;
2008 if (start < extent_start) {
2009 if (start + len <= extent_start)
2010 goto not_found;
2011 em->len = extent_end - extent_start;
2012 } else {
2013 em->len = len;
2014 }
2015 goto not_found_em;
2016 }
2017 em->block_start = EXTENT_MAP_INLINE;
2018
2019 if (!page) {
2020 em->start = extent_start;
2021 em->len = size;
2022 goto out;
2023 }
2024
2025 page_start = page_offset(page) + pg_offset;
2026 extent_offset = page_start - extent_start;
2027 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
2028 size - extent_offset);
2029 em->start = extent_start + extent_offset;
2030 em->len = (copy_size + root->sectorsize - 1) &
2031 ~((u64)root->sectorsize - 1);
2032 map = kmap(page);
2033 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
2034 if (create == 0 && !PageUptodate(page)) {
2035 read_extent_buffer(leaf, map + pg_offset, ptr,
2036 copy_size);
2037 flush_dcache_page(page);
2038 } else if (create && PageUptodate(page)) {
2039 if (!trans) {
2040 kunmap(page);
2041 free_extent_map(em);
2042 em = NULL;
2043 btrfs_release_path(root, path);
2044 trans = btrfs_start_transaction(root, 1);
2045 goto again;
2046 }
2047 write_extent_buffer(leaf, map + pg_offset, ptr,
2048 copy_size);
2049 btrfs_mark_buffer_dirty(leaf);
2050 }
2051 kunmap(page);
2052 set_extent_uptodate(io_tree, em->start,
2053 extent_map_end(em) - 1, GFP_NOFS);
2054 goto insert;
2055 } else {
2056 printk("unkknown found_type %d\n", found_type);
2057 WARN_ON(1);
2058 }
2059 not_found:
2060 em->start = start;
2061 em->len = len;
2062 not_found_em:
2063 em->block_start = EXTENT_MAP_HOLE;
2064 insert:
2065 btrfs_release_path(root, path);
2066 if (em->start > start || extent_map_end(em) <= start) {
2067 printk("bad extent! em: [%Lu %Lu] passed [%Lu %Lu]\n", em->start, em->len, start, len);
2068 err = -EIO;
2069 goto out;
2070 }
2071
2072 err = 0;
2073 spin_lock(&em_tree->lock);
2074 ret = add_extent_mapping(em_tree, em);
2075 if (ret == -EEXIST) {
2076 free_extent_map(em);
2077 em = lookup_extent_mapping(em_tree, start, len);
2078 if (!em) {
2079 err = -EIO;
2080 printk("failing to insert %Lu %Lu\n", start, len);
2081 }
2082 }
2083 spin_unlock(&em_tree->lock);
2084 out:
2085 btrfs_free_path(path);
2086 if (trans) {
2087 ret = btrfs_end_transaction(trans, root);
2088 if (!err)
2089 err = ret;
2090 }
2091 mutex_unlock(&root->fs_info->fs_mutex);
2092 if (err) {
2093 free_extent_map(em);
2094 WARN_ON(1);
2095 return ERR_PTR(err);
2096 }
2097 return em;
2098 }
2099
2100 static sector_t btrfs_bmap(struct address_space *mapping, sector_t iblock)
2101 {
2102 return extent_bmap(mapping, iblock, btrfs_get_extent);
2103 }
2104
2105 int btrfs_readpage(struct file *file, struct page *page)
2106 {
2107 struct extent_io_tree *tree;
2108 tree = &BTRFS_I(page->mapping->host)->io_tree;
2109 return extent_read_full_page(tree, page, btrfs_get_extent);
2110 }
2111
2112 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
2113 {
2114 struct extent_io_tree *tree;
2115
2116
2117 if (current->flags & PF_MEMALLOC) {
2118 redirty_page_for_writepage(wbc, page);
2119 unlock_page(page);
2120 return 0;
2121 }
2122 tree = &BTRFS_I(page->mapping->host)->io_tree;
2123 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
2124 }
2125
2126 static int btrfs_writepages(struct address_space *mapping,
2127 struct writeback_control *wbc)
2128 {
2129 struct extent_io_tree *tree;
2130 tree = &BTRFS_I(mapping->host)->io_tree;
2131 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
2132 }
2133
2134 static int
2135 btrfs_readpages(struct file *file, struct address_space *mapping,
2136 struct list_head *pages, unsigned nr_pages)
2137 {
2138 struct extent_io_tree *tree;
2139 tree = &BTRFS_I(mapping->host)->io_tree;
2140 return extent_readpages(tree, mapping, pages, nr_pages,
2141 btrfs_get_extent);
2142 }
2143
2144 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
2145 {
2146 struct extent_io_tree *tree;
2147 struct extent_map_tree *map;
2148 int ret;
2149
2150 tree = &BTRFS_I(page->mapping->host)->io_tree;
2151 map = &BTRFS_I(page->mapping->host)->extent_tree;
2152 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
2153 if (ret == 1) {
2154 ClearPagePrivate(page);
2155 set_page_private(page, 0);
2156 page_cache_release(page);
2157 }
2158 return ret;
2159 }
2160
2161 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
2162 {
2163 struct extent_io_tree *tree;
2164
2165 tree = &BTRFS_I(page->mapping->host)->io_tree;
2166 extent_invalidatepage(tree, page, offset);
2167 btrfs_releasepage(page, GFP_NOFS);
2168 }
2169
2170 /*
2171 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
2172 * called from a page fault handler when a page is first dirtied. Hence we must
2173 * be careful to check for EOF conditions here. We set the page up correctly
2174 * for a written page which means we get ENOSPC checking when writing into
2175 * holes and correct delalloc and unwritten extent mapping on filesystems that
2176 * support these features.
2177 *
2178 * We are not allowed to take the i_mutex here so we have to play games to
2179 * protect against truncate races as the page could now be beyond EOF. Because
2180 * vmtruncate() writes the inode size before removing pages, once we have the
2181 * page lock we can determine safely if the page is beyond EOF. If it is not
2182 * beyond EOF, then the page is guaranteed safe against truncation until we
2183 * unlock the page.
2184 */
2185 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
2186 {
2187 struct inode *inode = fdentry(vma->vm_file)->d_inode;
2188 struct btrfs_root *root = BTRFS_I(inode)->root;
2189 unsigned long end;
2190 loff_t size;
2191 int ret;
2192 u64 page_start;
2193
2194 mutex_lock(&root->fs_info->fs_mutex);
2195 ret = btrfs_check_free_space(root, PAGE_CACHE_SIZE, 0);
2196 mutex_unlock(&root->fs_info->fs_mutex);
2197 if (ret)
2198 goto out;
2199
2200 ret = -EINVAL;
2201
2202 lock_page(page);
2203 wait_on_page_writeback(page);
2204 size = i_size_read(inode);
2205 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2206
2207 if ((page->mapping != inode->i_mapping) ||
2208 (page_start > size)) {
2209 /* page got truncated out from underneath us */
2210 goto out_unlock;
2211 }
2212
2213 /* page is wholly or partially inside EOF */
2214 if (page_start + PAGE_CACHE_SIZE > size)
2215 end = size & ~PAGE_CACHE_MASK;
2216 else
2217 end = PAGE_CACHE_SIZE;
2218
2219 ret = btrfs_cow_one_page(inode, page, end);
2220
2221 out_unlock:
2222 unlock_page(page);
2223 out:
2224 return ret;
2225 }
2226
2227 static void btrfs_truncate(struct inode *inode)
2228 {
2229 struct btrfs_root *root = BTRFS_I(inode)->root;
2230 int ret;
2231 struct btrfs_trans_handle *trans;
2232 unsigned long nr;
2233
2234 if (!S_ISREG(inode->i_mode))
2235 return;
2236 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
2237 return;
2238
2239 btrfs_truncate_page(inode->i_mapping, inode->i_size);
2240
2241 mutex_lock(&root->fs_info->fs_mutex);
2242 trans = btrfs_start_transaction(root, 1);
2243 btrfs_set_trans_block_group(trans, inode);
2244
2245 /* FIXME, add redo link to tree so we don't leak on crash */
2246 ret = btrfs_truncate_in_trans(trans, root, inode,
2247 BTRFS_EXTENT_DATA_KEY);
2248 btrfs_update_inode(trans, root, inode);
2249 nr = trans->blocks_used;
2250
2251 ret = btrfs_end_transaction(trans, root);
2252 BUG_ON(ret);
2253 mutex_unlock(&root->fs_info->fs_mutex);
2254 btrfs_btree_balance_dirty(root, nr);
2255 btrfs_throttle(root);
2256 }
2257
2258 static int noinline create_subvol(struct btrfs_root *root, char *name,
2259 int namelen)
2260 {
2261 struct btrfs_trans_handle *trans;
2262 struct btrfs_key key;
2263 struct btrfs_root_item root_item;
2264 struct btrfs_inode_item *inode_item;
2265 struct extent_buffer *leaf;
2266 struct btrfs_root *new_root = root;
2267 struct inode *inode;
2268 struct inode *dir;
2269 int ret;
2270 int err;
2271 u64 objectid;
2272 u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
2273 unsigned long nr = 1;
2274
2275 mutex_lock(&root->fs_info->fs_mutex);
2276 ret = btrfs_check_free_space(root, 1, 0);
2277 if (ret)
2278 goto fail_commit;
2279
2280 trans = btrfs_start_transaction(root, 1);
2281 BUG_ON(!trans);
2282
2283 ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
2284 0, &objectid);
2285 if (ret)
2286 goto fail;
2287
2288 leaf = __btrfs_alloc_free_block(trans, root, root->leafsize,
2289 objectid, trans->transid, 0, 0,
2290 0, 0);
2291 if (IS_ERR(leaf))
2292 return PTR_ERR(leaf);
2293
2294 btrfs_set_header_nritems(leaf, 0);
2295 btrfs_set_header_level(leaf, 0);
2296 btrfs_set_header_bytenr(leaf, leaf->start);
2297 btrfs_set_header_generation(leaf, trans->transid);
2298 btrfs_set_header_owner(leaf, objectid);
2299
2300 write_extent_buffer(leaf, root->fs_info->fsid,
2301 (unsigned long)btrfs_header_fsid(leaf),
2302 BTRFS_FSID_SIZE);
2303 btrfs_mark_buffer_dirty(leaf);
2304
2305 inode_item = &root_item.inode;
2306 memset(inode_item, 0, sizeof(*inode_item));
2307 inode_item->generation = cpu_to_le64(1);
2308 inode_item->size = cpu_to_le64(3);
2309 inode_item->nlink = cpu_to_le32(1);
2310 inode_item->nblocks = cpu_to_le64(1);
2311 inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
2312
2313 btrfs_set_root_bytenr(&root_item, leaf->start);
2314 btrfs_set_root_level(&root_item, 0);
2315 btrfs_set_root_refs(&root_item, 1);
2316 btrfs_set_root_used(&root_item, 0);
2317
2318 memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
2319 root_item.drop_level = 0;
2320
2321 free_extent_buffer(leaf);
2322 leaf = NULL;
2323
2324 btrfs_set_root_dirid(&root_item, new_dirid);
2325
2326 key.objectid = objectid;
2327 key.offset = 1;
2328 btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
2329 ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
2330 &root_item);
2331 if (ret)
2332 goto fail;
2333
2334 /*
2335 * insert the directory item
2336 */
2337 key.offset = (u64)-1;
2338 dir = root->fs_info->sb->s_root->d_inode;
2339 ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
2340 name, namelen, dir->i_ino, &key,
2341 BTRFS_FT_DIR);
2342 if (ret)
2343 goto fail;
2344
2345 ret = btrfs_insert_inode_ref(trans, root->fs_info->tree_root,
2346 name, namelen, objectid,
2347 root->fs_info->sb->s_root->d_inode->i_ino);
2348 if (ret)
2349 goto fail;
2350
2351 ret = btrfs_commit_transaction(trans, root);
2352 if (ret)
2353 goto fail_commit;
2354
2355 new_root = btrfs_read_fs_root(root->fs_info, &key, name, namelen);
2356 BUG_ON(!new_root);
2357
2358 trans = btrfs_start_transaction(new_root, 1);
2359 BUG_ON(!trans);
2360
2361 inode = btrfs_new_inode(trans, new_root, "..", 2, new_dirid,
2362 new_dirid,
2363 BTRFS_I(dir)->block_group, S_IFDIR | 0700);
2364 if (IS_ERR(inode))
2365 goto fail;
2366 inode->i_op = &btrfs_dir_inode_operations;
2367 inode->i_fop = &btrfs_dir_file_operations;
2368 new_root->inode = inode;
2369
2370 ret = btrfs_insert_inode_ref(trans, new_root, "..", 2, new_dirid,
2371 new_dirid);
2372 inode->i_nlink = 1;
2373 inode->i_size = 0;
2374 ret = btrfs_update_inode(trans, new_root, inode);
2375 if (ret)
2376 goto fail;
2377 fail:
2378 nr = trans->blocks_used;
2379 err = btrfs_commit_transaction(trans, new_root);
2380 if (err && !ret)
2381 ret = err;
2382 fail_commit:
2383 mutex_unlock(&root->fs_info->fs_mutex);
2384 btrfs_btree_balance_dirty(root, nr);
2385 btrfs_throttle(root);
2386 return ret;
2387 }
2388
2389 static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
2390 {
2391 struct btrfs_pending_snapshot *pending_snapshot;
2392 struct btrfs_trans_handle *trans;
2393 int ret;
2394 int err;
2395 unsigned long nr = 0;
2396
2397 if (!root->ref_cows)
2398 return -EINVAL;
2399
2400 mutex_lock(&root->fs_info->fs_mutex);
2401 ret = btrfs_check_free_space(root, 1, 0);
2402 if (ret)
2403 goto fail_unlock;
2404
2405 pending_snapshot = kmalloc(sizeof(*pending_snapshot), GFP_NOFS);
2406 if (!pending_snapshot) {
2407 ret = -ENOMEM;
2408 goto fail_unlock;
2409 }
2410 pending_snapshot->name = kmalloc(namelen + 1, GFP_NOFS);
2411 if (!pending_snapshot->name) {
2412 ret = -ENOMEM;
2413 kfree(pending_snapshot);
2414 goto fail_unlock;
2415 }
2416 memcpy(pending_snapshot->name, name, namelen);
2417 pending_snapshot->name[namelen] = '\0';
2418 trans = btrfs_start_transaction(root, 1);
2419 BUG_ON(!trans);
2420 pending_snapshot->root = root;
2421 list_add(&pending_snapshot->list,
2422 &trans->transaction->pending_snapshots);
2423 ret = btrfs_update_inode(trans, root, root->inode);
2424 err = btrfs_commit_transaction(trans, root);
2425
2426 fail_unlock:
2427 mutex_unlock(&root->fs_info->fs_mutex);
2428 btrfs_btree_balance_dirty(root, nr);
2429 btrfs_throttle(root);
2430 return ret;
2431 }
2432
2433 unsigned long btrfs_force_ra(struct address_space *mapping,
2434 struct file_ra_state *ra, struct file *file,
2435 pgoff_t offset, pgoff_t last_index)
2436 {
2437 pgoff_t req_size;
2438
2439 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
2440 req_size = last_index - offset + 1;
2441 offset = page_cache_readahead(mapping, ra, file, offset, req_size);
2442 return offset;
2443 #else
2444 req_size = min(last_index - offset + 1, (pgoff_t)128);
2445 page_cache_sync_readahead(mapping, ra, file, offset, req_size);
2446 return offset + req_size;
2447 #endif
2448 }
2449
2450 int btrfs_defrag_file(struct file *file) {
2451 struct inode *inode = fdentry(file)->d_inode;
2452 struct btrfs_root *root = BTRFS_I(inode)->root;
2453 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2454 struct page *page;
2455 unsigned long last_index;
2456 unsigned long ra_index = 0;
2457 u64 page_start;
2458 u64 page_end;
2459 u64 delalloc_start;
2460 u64 existing_delalloc;
2461 unsigned long i;
2462 int ret;
2463
2464 mutex_lock(&root->fs_info->fs_mutex);
2465 ret = btrfs_check_free_space(root, inode->i_size, 0);
2466 mutex_unlock(&root->fs_info->fs_mutex);
2467 if (ret)
2468 return -ENOSPC;
2469
2470 mutex_lock(&inode->i_mutex);
2471 last_index = inode->i_size >> PAGE_CACHE_SHIFT;
2472 for (i = 0; i <= last_index; i++) {
2473 if (i == ra_index) {
2474 ra_index = btrfs_force_ra(inode->i_mapping,
2475 &file->f_ra,
2476 file, ra_index, last_index);
2477 }
2478 page = grab_cache_page(inode->i_mapping, i);
2479 if (!page)
2480 goto out_unlock;
2481 if (!PageUptodate(page)) {
2482 btrfs_readpage(NULL, page);
2483 lock_page(page);
2484 if (!PageUptodate(page)) {
2485 unlock_page(page);
2486 page_cache_release(page);
2487 goto out_unlock;
2488 }
2489 }
2490 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
2491 page_end = page_start + PAGE_CACHE_SIZE - 1;
2492
2493 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
2494 delalloc_start = page_start;
2495 existing_delalloc =
2496 count_range_bits(&BTRFS_I(inode)->io_tree,
2497 &delalloc_start, page_end,
2498 PAGE_CACHE_SIZE, EXTENT_DELALLOC);
2499 set_extent_delalloc(io_tree, page_start,
2500 page_end, GFP_NOFS);
2501
2502 spin_lock(&root->fs_info->delalloc_lock);
2503 root->fs_info->delalloc_bytes += PAGE_CACHE_SIZE -
2504 existing_delalloc;
2505 spin_unlock(&root->fs_info->delalloc_lock);
2506
2507 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
2508 set_page_dirty(page);
2509 unlock_page(page);
2510 page_cache_release(page);
2511 balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);
2512 }
2513
2514 out_unlock:
2515 mutex_unlock(&inode->i_mutex);
2516 return 0;
2517 }
2518
2519 static int btrfs_ioctl_resize(struct btrfs_root *root, void __user *arg)
2520 {
2521 u64 new_size;
2522 u64 old_size;
2523 struct btrfs_ioctl_vol_args *vol_args;
2524 struct btrfs_trans_handle *trans;
2525 char *sizestr;
2526 int ret = 0;
2527 int namelen;
2528 int mod = 0;
2529
2530 vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS);
2531
2532 if (!vol_args)
2533 return -ENOMEM;
2534
2535 if (copy_from_user(vol_args, arg, sizeof(*vol_args))) {
2536 ret = -EFAULT;
2537 goto out;
2538 }
2539 namelen = strlen(vol_args->name);
2540 if (namelen > BTRFS_VOL_NAME_MAX) {
2541 ret = -EINVAL;
2542 goto out;
2543 }
2544
2545 sizestr = vol_args->name;
2546 if (!strcmp(sizestr, "max"))
2547 new_size = root->fs_info->sb->s_bdev->bd_inode->i_size;
2548 else {
2549 if (sizestr[0] == '-') {
2550 mod = -1;
2551 sizestr++;
2552 } else if (sizestr[0] == '+') {
2553 mod = 1;
2554 sizestr++;
2555 }
2556 new_size = btrfs_parse_size(sizestr);
2557 if (new_size == 0) {
2558 ret = -EINVAL;
2559 goto out;
2560 }
2561 }
2562
2563 mutex_lock(&root->fs_info->fs_mutex);
2564 old_size = btrfs_super_total_bytes(&root->fs_info->super_copy);
2565
2566 if (mod < 0) {
2567 if (new_size > old_size) {
2568 ret = -EINVAL;
2569 goto out_unlock;
2570 }
2571 new_size = old_size - new_size;
2572 } else if (mod > 0) {
2573 new_size = old_size + new_size;
2574 }
2575
2576 if (new_size < 256 * 1024 * 1024) {
2577 ret = -EINVAL;
2578 goto out_unlock;
2579 }
2580 if (new_size > root->fs_info->sb->s_bdev->bd_inode->i_size) {
2581 ret = -EFBIG;
2582 goto out_unlock;
2583 }
2584
2585 do_div(new_size, root->sectorsize);
2586 new_size *= root->sectorsize;
2587
2588 printk("new size is %Lu\n", new_size);
2589 if (new_size > old_size) {
2590 trans = btrfs_start_transaction(root, 1);
2591 ret = btrfs_grow_extent_tree(trans, root, new_size);
2592 btrfs_commit_transaction(trans, root);
2593 } else {
2594 ret = btrfs_shrink_extent_tree(root, new_size);
2595 }
2596
2597 out_unlock:
2598 mutex_unlock(&root->fs_info->fs_mutex);
2599 out:
2600 kfree(vol_args);
2601 return ret;
2602 }
2603
2604 static int noinline btrfs_ioctl_snap_create(struct btrfs_root *root,
2605 void __user *arg)
2606 {
2607 struct btrfs_ioctl_vol_args *vol_args;
2608 struct btrfs_dir_item *di;
2609 struct btrfs_path *path;
2610 u64 root_dirid;
2611 int namelen;
2612 int ret;
2613
2614 vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS);
2615
2616 if (!vol_args)
2617 return -ENOMEM;
2618
2619 if (copy_from_user(vol_args, arg, sizeof(*vol_args))) {
2620 ret = -EFAULT;
2621 goto out;
2622 }
2623
2624 namelen = strlen(vol_args->name);
2625 if (namelen > BTRFS_VOL_NAME_MAX) {
2626 ret = -EINVAL;
2627 goto out;
2628 }
2629 if (strchr(vol_args->name, '/')) {
2630 ret = -EINVAL;
2631 goto out;
2632 }
2633
2634 path = btrfs_alloc_path();
2635 if (!path) {
2636 ret = -ENOMEM;
2637 goto out;
2638 }
2639
2640 root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
2641 mutex_lock(&root->fs_info->fs_mutex);
2642 di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
2643 path, root_dirid,
2644 vol_args->name, namelen, 0);
2645 mutex_unlock(&root->fs_info->fs_mutex);
2646 btrfs_free_path(path);
2647
2648 if (di && !IS_ERR(di)) {
2649 ret = -EEXIST;
2650 goto out;
2651 }
2652
2653 if (IS_ERR(di)) {
2654 ret = PTR_ERR(di);
2655 goto out;
2656 }
2657
2658 if (root == root->fs_info->tree_root)
2659 ret = create_subvol(root, vol_args->name, namelen);
2660 else
2661 ret = create_snapshot(root, vol_args->name, namelen);
2662 out:
2663 kfree(vol_args);
2664 return ret;
2665 }
2666
2667 static int btrfs_ioctl_defrag(struct file *file)
2668 {
2669 struct inode *inode = fdentry(file)->d_inode;
2670 struct btrfs_root *root = BTRFS_I(inode)->root;
2671
2672 switch (inode->i_mode & S_IFMT) {
2673 case S_IFDIR:
2674 mutex_lock(&root->fs_info->fs_mutex);
2675 btrfs_defrag_root(root, 0);
2676 btrfs_defrag_root(root->fs_info->extent_root, 0);
2677 mutex_unlock(&root->fs_info->fs_mutex);
2678 break;
2679 case S_IFREG:
2680 btrfs_defrag_file(file);
2681 break;
2682 }
2683
2684 return 0;
2685 }
2686
2687 long btrfs_ioctl(struct file *file, unsigned int
2688 cmd, unsigned long arg)
2689 {
2690 struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2691
2692 switch (cmd) {
2693 case BTRFS_IOC_SNAP_CREATE:
2694 return btrfs_ioctl_snap_create(root, (void __user *)arg);
2695 case BTRFS_IOC_DEFRAG:
2696 return btrfs_ioctl_defrag(file);
2697 case BTRFS_IOC_RESIZE:
2698 return btrfs_ioctl_resize(root, (void __user *)arg);
2699 }
2700
2701 return -ENOTTY;
2702 }
2703
2704 /*
2705 * Called inside transaction, so use GFP_NOFS
2706 */
2707 struct inode *btrfs_alloc_inode(struct super_block *sb)
2708 {
2709 struct btrfs_inode *ei;
2710
2711 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
2712 if (!ei)
2713 return NULL;
2714 ei->last_trans = 0;
2715 ei->ordered_trans = 0;
2716 return &ei->vfs_inode;
2717 }
2718
2719 void btrfs_destroy_inode(struct inode *inode)
2720 {
2721 WARN_ON(!list_empty(&inode->i_dentry));
2722 WARN_ON(inode->i_data.nrpages);
2723
2724 btrfs_drop_extent_cache(inode, 0, (u64)-1);
2725 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
2726 }
2727
2728 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
2729 static void init_once(struct kmem_cache * cachep, void *foo)
2730 #else
2731 static void init_once(void * foo, struct kmem_cache * cachep,
2732 unsigned long flags)
2733 #endif
2734 {
2735 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
2736
2737 inode_init_once(&ei->vfs_inode);
2738 }
2739
2740 void btrfs_destroy_cachep(void)
2741 {
2742 if (btrfs_inode_cachep)
2743 kmem_cache_destroy(btrfs_inode_cachep);
2744 if (btrfs_trans_handle_cachep)
2745 kmem_cache_destroy(btrfs_trans_handle_cachep);
2746 if (btrfs_transaction_cachep)
2747 kmem_cache_destroy(btrfs_transaction_cachep);
2748 if (btrfs_bit_radix_cachep)
2749 kmem_cache_destroy(btrfs_bit_radix_cachep);
2750 if (btrfs_path_cachep)
2751 kmem_cache_destroy(btrfs_path_cachep);
2752 }
2753
2754 struct kmem_cache *btrfs_cache_create(const char *name, size_t size,
2755 unsigned long extra_flags,
2756 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
2757 void (*ctor)(struct kmem_cache *, void *)
2758 #else
2759 void (*ctor)(void *, struct kmem_cache *,
2760 unsigned long)
2761 #endif
2762 )
2763 {
2764 return kmem_cache_create(name, size, 0, (SLAB_RECLAIM_ACCOUNT |
2765 SLAB_MEM_SPREAD | extra_flags), ctor
2766 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
2767 ,NULL
2768 #endif
2769 );
2770 }
2771
2772 int btrfs_init_cachep(void)
2773 {
2774 btrfs_inode_cachep = btrfs_cache_create("btrfs_inode_cache",
2775 sizeof(struct btrfs_inode),
2776 0, init_once);
2777 if (!btrfs_inode_cachep)
2778 goto fail;
2779 btrfs_trans_handle_cachep =
2780 btrfs_cache_create("btrfs_trans_handle_cache",
2781 sizeof(struct btrfs_trans_handle),
2782 0, NULL);
2783 if (!btrfs_trans_handle_cachep)
2784 goto fail;
2785 btrfs_transaction_cachep = btrfs_cache_create("btrfs_transaction_cache",
2786 sizeof(struct btrfs_transaction),
2787 0, NULL);
2788 if (!btrfs_transaction_cachep)
2789 goto fail;
2790 btrfs_path_cachep = btrfs_cache_create("btrfs_path_cache",
2791 sizeof(struct btrfs_path),
2792 0, NULL);
2793 if (!btrfs_path_cachep)
2794 goto fail;
2795 btrfs_bit_radix_cachep = btrfs_cache_create("btrfs_radix", 256,
2796 SLAB_DESTROY_BY_RCU, NULL);
2797 if (!btrfs_bit_radix_cachep)
2798 goto fail;
2799 return 0;
2800 fail:
2801 btrfs_destroy_cachep();
2802 return -ENOMEM;
2803 }
2804
2805 static int btrfs_getattr(struct vfsmount *mnt,
2806 struct dentry *dentry, struct kstat *stat)
2807 {
2808 struct inode *inode = dentry->d_inode;
2809 generic_fillattr(inode, stat);
2810 stat->blksize = PAGE_CACHE_SIZE;
2811 return 0;
2812 }
2813
2814 static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
2815 struct inode * new_dir,struct dentry *new_dentry)
2816 {
2817 struct btrfs_trans_handle *trans;
2818 struct btrfs_root *root = BTRFS_I(old_dir)->root;
2819 struct inode *new_inode = new_dentry->d_inode;
2820 struct inode *old_inode = old_dentry->d_inode;
2821 struct timespec ctime = CURRENT_TIME;
2822 struct btrfs_path *path;
2823 int ret;
2824
2825 if (S_ISDIR(old_inode->i_mode) && new_inode &&
2826 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
2827 return -ENOTEMPTY;
2828 }
2829
2830 mutex_lock(&root->fs_info->fs_mutex);
2831 ret = btrfs_check_free_space(root, 1, 0);
2832 if (ret)
2833 goto out_unlock;
2834
2835 trans = btrfs_start_transaction(root, 1);
2836
2837 btrfs_set_trans_block_group(trans, new_dir);
2838 path = btrfs_alloc_path();
2839 if (!path) {
2840 ret = -ENOMEM;
2841 goto out_fail;
2842 }
2843
2844 old_dentry->d_inode->i_nlink++;
2845 old_dir->i_ctime = old_dir->i_mtime = ctime;
2846 new_dir->i_ctime = new_dir->i_mtime = ctime;
2847 old_inode->i_ctime = ctime;
2848
2849 ret = btrfs_unlink_trans(trans, root, old_dir, old_dentry);
2850 if (ret)
2851 goto out_fail;
2852
2853 if (new_inode) {
2854 new_inode->i_ctime = CURRENT_TIME;
2855 ret = btrfs_unlink_trans(trans, root, new_dir, new_dentry);
2856 if (ret)
2857 goto out_fail;
2858 }
2859 ret = btrfs_add_link(trans, new_dentry, old_inode, 1);
2860 if (ret)
2861 goto out_fail;
2862
2863 out_fail:
2864 btrfs_free_path(path);
2865 btrfs_end_transaction(trans, root);
2866 out_unlock:
2867 mutex_unlock(&root->fs_info->fs_mutex);
2868 return ret;
2869 }
2870
2871 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
2872 const char *symname)
2873 {
2874 struct btrfs_trans_handle *trans;
2875 struct btrfs_root *root = BTRFS_I(dir)->root;
2876 struct btrfs_path *path;
2877 struct btrfs_key key;
2878 struct inode *inode = NULL;
2879 int err;
2880 int drop_inode = 0;
2881 u64 objectid;
2882 int name_len;
2883 int datasize;
2884 unsigned long ptr;
2885 struct btrfs_file_extent_item *ei;
2886 struct extent_buffer *leaf;
2887 unsigned long nr = 0;
2888
2889 name_len = strlen(symname) + 1;
2890 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
2891 return -ENAMETOOLONG;
2892
2893 mutex_lock(&root->fs_info->fs_mutex);
2894 err = btrfs_check_free_space(root, 1, 0);
2895 if (err)
2896 goto out_fail;
2897
2898 trans = btrfs_start_transaction(root, 1);
2899 btrfs_set_trans_block_group(trans, dir);
2900
2901 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2902 if (err) {
2903 err = -ENOSPC;
2904 goto out_unlock;
2905 }
2906
2907 inode = btrfs_new_inode(trans, root, dentry->d_name.name,
2908 dentry->d_name.len,
2909 dentry->d_parent->d_inode->i_ino, objectid,
2910 BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO);
2911 err = PTR_ERR(inode);
2912 if (IS_ERR(inode))
2913 goto out_unlock;
2914
2915 btrfs_set_trans_block_group(trans, inode);
2916 err = btrfs_add_nondir(trans, dentry, inode, 0);
2917 if (err)
2918 drop_inode = 1;
2919 else {
2920 inode->i_mapping->a_ops = &btrfs_aops;
2921 inode->i_fop = &btrfs_file_operations;
2922 inode->i_op = &btrfs_file_inode_operations;
2923 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
2924 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
2925 inode->i_mapping, GFP_NOFS);
2926 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
2927 }
2928 dir->i_sb->s_dirt = 1;
2929 btrfs_update_inode_block_group(trans, inode);
2930 btrfs_update_inode_block_group(trans, dir);
2931 if (drop_inode)
2932 goto out_unlock;
2933
2934 path = btrfs_alloc_path();
2935 BUG_ON(!path);
2936 key.objectid = inode->i_ino;
2937 key.offset = 0;
2938 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
2939 datasize = btrfs_file_extent_calc_inline_size(name_len);
2940 err = btrfs_insert_empty_item(trans, root, path, &key,
2941 datasize);
2942 if (err) {
2943 drop_inode = 1;
2944 goto out_unlock;
2945 }
2946 leaf = path->nodes[0];
2947 ei = btrfs_item_ptr(leaf, path->slots[0],
2948 struct btrfs_file_extent_item);
2949 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
2950 btrfs_set_file_extent_type(leaf, ei,
2951 BTRFS_FILE_EXTENT_INLINE);
2952 ptr = btrfs_file_extent_inline_start(ei);
2953 write_extent_buffer(leaf, symname, ptr, name_len);
2954 btrfs_mark_buffer_dirty(leaf);
2955 btrfs_free_path(path);
2956
2957 inode->i_op = &btrfs_symlink_inode_operations;
2958 inode->i_mapping->a_ops = &btrfs_symlink_aops;
2959 inode->i_size = name_len - 1;
2960 err = btrfs_update_inode(trans, root, inode);
2961 if (err)
2962 drop_inode = 1;
2963
2964 out_unlock:
2965 nr = trans->blocks_used;
2966 btrfs_end_transaction(trans, root);
2967 out_fail:
2968 mutex_unlock(&root->fs_info->fs_mutex);
2969 if (drop_inode) {
2970 inode_dec_link_count(inode);
2971 iput(inode);
2972 }
2973 btrfs_btree_balance_dirty(root, nr);
2974 btrfs_throttle(root);
2975 return err;
2976 }
2977 static int btrfs_permission(struct inode *inode, int mask,
2978 struct nameidata *nd)
2979 {
2980 if (btrfs_test_flag(inode, READONLY) && (mask & MAY_WRITE))
2981 return -EACCES;
2982 return generic_permission(inode, mask, NULL);
2983 }
2984
2985 static struct inode_operations btrfs_dir_inode_operations = {
2986 .lookup = btrfs_lookup,
2987 .create = btrfs_create,
2988 .unlink = btrfs_unlink,
2989 .link = btrfs_link,
2990 .mkdir = btrfs_mkdir,
2991 .rmdir = btrfs_rmdir,
2992 .rename = btrfs_rename,
2993 .symlink = btrfs_symlink,
2994 .setattr = btrfs_setattr,
2995 .mknod = btrfs_mknod,
2996 .setxattr = generic_setxattr,
2997 .getxattr = generic_getxattr,
2998 .listxattr = btrfs_listxattr,
2999 .removexattr = generic_removexattr,
3000 .permission = btrfs_permission,
3001 };
3002 static struct inode_operations btrfs_dir_ro_inode_operations = {
3003 .lookup = btrfs_lookup,
3004 .permission = btrfs_permission,
3005 };
3006 static struct file_operations btrfs_dir_file_operations = {
3007 .llseek = generic_file_llseek,
3008 .read = generic_read_dir,
3009 .readdir = btrfs_readdir,
3010 .unlocked_ioctl = btrfs_ioctl,
3011 #ifdef CONFIG_COMPAT
3012 .compat_ioctl = btrfs_ioctl,
3013 #endif
3014 };
3015
3016 static struct extent_io_ops btrfs_extent_io_ops = {
3017 .fill_delalloc = run_delalloc_range,
3018 .writepage_io_hook = btrfs_writepage_io_hook,
3019 .readpage_io_hook = btrfs_readpage_io_hook,
3020 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
3021 };
3022
3023 static struct address_space_operations btrfs_aops = {
3024 .readpage = btrfs_readpage,
3025 .writepage = btrfs_writepage,
3026 .writepages = btrfs_writepages,
3027 .readpages = btrfs_readpages,
3028 .sync_page = block_sync_page,
3029 .bmap = btrfs_bmap,
3030 .invalidatepage = btrfs_invalidatepage,
3031 .releasepage = btrfs_releasepage,
3032 .set_page_dirty = __set_page_dirty_nobuffers,
3033 };
3034
3035 static struct address_space_operations btrfs_symlink_aops = {
3036 .readpage = btrfs_readpage,
3037 .writepage = btrfs_writepage,
3038 .invalidatepage = btrfs_invalidatepage,
3039 .releasepage = btrfs_releasepage,
3040 };
3041
3042 static struct inode_operations btrfs_file_inode_operations = {
3043 .truncate = btrfs_truncate,
3044 .getattr = btrfs_getattr,
3045 .setattr = btrfs_setattr,
3046 .setxattr = generic_setxattr,
3047 .getxattr = generic_getxattr,
3048 .listxattr = btrfs_listxattr,
3049 .removexattr = generic_removexattr,
3050 .permission = btrfs_permission,
3051 };
3052 static struct inode_operations btrfs_special_inode_operations = {
3053 .getattr = btrfs_getattr,
3054 .setattr = btrfs_setattr,
3055 .permission = btrfs_permission,
3056 };
3057 static struct inode_operations btrfs_symlink_inode_operations = {
3058 .readlink = generic_readlink,
3059 .follow_link = page_follow_link_light,
3060 .put_link = page_put_link,
3061 .permission = btrfs_permission,
3062 };
Linux kernel - Deliverables
This page took 0.165161 seconds and 6 git commands to generate.