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btrfs_lookup_bio_sums seems broken, go back to the readpage_io_hook for now
[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/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.h>
23 #include <linux/fs.h>
24 #include <linux/pagemap.h>
25 #include <linux/highmem.h>
26 #include <linux/time.h>
27 #include <linux/init.h>
28 #include <linux/string.h>
29 #include <linux/smp_lock.h>
30 #include <linux/backing-dev.h>
31 #include <linux/mpage.h>
32 #include <linux/swap.h>
33 #include <linux/writeback.h>
34 #include <linux/statfs.h>
35 #include <linux/compat.h>
36 #include <linux/bit_spinlock.h>
37 #include <linux/version.h>
38 #include <linux/xattr.h>
39 #include <linux/posix_acl.h>
40 #include "ctree.h"
41 #include "disk-io.h"
42 #include "transaction.h"
43 #include "btrfs_inode.h"
44 #include "ioctl.h"
45 #include "print-tree.h"
46 #include "volumes.h"
47 #include "ordered-data.h"
48
49 struct btrfs_iget_args {
50 u64 ino;
51 struct btrfs_root *root;
52 };
53
54 static struct inode_operations btrfs_dir_inode_operations;
55 static struct inode_operations btrfs_symlink_inode_operations;
56 static struct inode_operations btrfs_dir_ro_inode_operations;
57 static struct inode_operations btrfs_special_inode_operations;
58 static struct inode_operations btrfs_file_inode_operations;
59 static struct address_space_operations btrfs_aops;
60 static struct address_space_operations btrfs_symlink_aops;
61 static struct file_operations btrfs_dir_file_operations;
62 static struct extent_io_ops btrfs_extent_io_ops;
63
64 static struct kmem_cache *btrfs_inode_cachep;
65 struct kmem_cache *btrfs_trans_handle_cachep;
66 struct kmem_cache *btrfs_transaction_cachep;
67 struct kmem_cache *btrfs_bit_radix_cachep;
68 struct kmem_cache *btrfs_path_cachep;
69
70 #define S_SHIFT 12
71 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
72 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
73 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
74 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
75 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
76 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
77 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
78 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
79 };
80
81 static void btrfs_truncate(struct inode *inode);
82
83 int btrfs_check_free_space(struct btrfs_root *root, u64 num_required,
84 int for_del)
85 {
86 u64 total;
87 u64 used;
88 u64 thresh;
89 unsigned long flags;
90 int ret = 0;
91
92 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
93 total = btrfs_super_total_bytes(&root->fs_info->super_copy);
94 used = btrfs_super_bytes_used(&root->fs_info->super_copy);
95 if (for_del)
96 thresh = total * 90;
97 else
98 thresh = total * 85;
99
100 do_div(thresh, 100);
101
102 if (used + root->fs_info->delalloc_bytes + num_required > thresh)
103 ret = -ENOSPC;
104 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
105 return ret;
106 }
107
108 static int cow_file_range(struct inode *inode, u64 start, u64 end)
109 {
110 struct btrfs_root *root = BTRFS_I(inode)->root;
111 struct btrfs_trans_handle *trans;
112 u64 alloc_hint = 0;
113 u64 num_bytes;
114 u64 cur_alloc_size;
115 u64 blocksize = root->sectorsize;
116 u64 orig_num_bytes;
117 struct btrfs_key ins;
118 struct extent_map *em;
119 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
120 int ret = 0;
121
122 trans = btrfs_join_transaction(root, 1);
123 BUG_ON(!trans);
124 btrfs_set_trans_block_group(trans, inode);
125
126 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
127 num_bytes = max(blocksize, num_bytes);
128 orig_num_bytes = num_bytes;
129
130 if (alloc_hint == EXTENT_MAP_INLINE)
131 goto out;
132
133 BUG_ON(num_bytes > btrfs_super_total_bytes(&root->fs_info->super_copy));
134 mutex_lock(&BTRFS_I(inode)->extent_mutex);
135 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1);
136 mutex_unlock(&BTRFS_I(inode)->extent_mutex);
137
138 while(num_bytes > 0) {
139 cur_alloc_size = min(num_bytes, root->fs_info->max_extent);
140 ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
141 root->sectorsize, 0, 0,
142 (u64)-1, &ins, 1);
143 if (ret) {
144 WARN_ON(1);
145 goto out;
146 }
147 em = alloc_extent_map(GFP_NOFS);
148 em->start = start;
149 em->len = ins.offset;
150 em->block_start = ins.objectid;
151 em->bdev = root->fs_info->fs_devices->latest_bdev;
152 mutex_lock(&BTRFS_I(inode)->extent_mutex);
153 set_bit(EXTENT_FLAG_PINNED, &em->flags);
154 while(1) {
155 spin_lock(&em_tree->lock);
156 ret = add_extent_mapping(em_tree, em);
157 spin_unlock(&em_tree->lock);
158 if (ret != -EEXIST) {
159 free_extent_map(em);
160 break;
161 }
162 btrfs_drop_extent_cache(inode, start,
163 start + ins.offset - 1);
164 }
165 mutex_unlock(&BTRFS_I(inode)->extent_mutex);
166
167 cur_alloc_size = ins.offset;
168 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
169 ins.offset);
170 BUG_ON(ret);
171 if (num_bytes < cur_alloc_size) {
172 printk("num_bytes %Lu cur_alloc %Lu\n", num_bytes,
173 cur_alloc_size);
174 break;
175 }
176 num_bytes -= cur_alloc_size;
177 alloc_hint = ins.objectid + ins.offset;
178 start += cur_alloc_size;
179 }
180 out:
181 btrfs_end_transaction(trans, root);
182 return ret;
183 }
184
185 static int run_delalloc_nocow(struct inode *inode, u64 start, u64 end)
186 {
187 u64 extent_start;
188 u64 extent_end;
189 u64 bytenr;
190 u64 cow_end;
191 u64 loops = 0;
192 u64 total_fs_bytes;
193 struct btrfs_root *root = BTRFS_I(inode)->root;
194 struct btrfs_block_group_cache *block_group;
195 struct extent_buffer *leaf;
196 int found_type;
197 struct btrfs_path *path;
198 struct btrfs_file_extent_item *item;
199 int ret;
200 int err;
201 struct btrfs_key found_key;
202
203 total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
204 path = btrfs_alloc_path();
205 BUG_ON(!path);
206 again:
207 ret = btrfs_lookup_file_extent(NULL, root, path,
208 inode->i_ino, start, 0);
209 if (ret < 0) {
210 btrfs_free_path(path);
211 return ret;
212 }
213
214 cow_end = end;
215 if (ret != 0) {
216 if (path->slots[0] == 0)
217 goto not_found;
218 path->slots[0]--;
219 }
220
221 leaf = path->nodes[0];
222 item = btrfs_item_ptr(leaf, path->slots[0],
223 struct btrfs_file_extent_item);
224
225 /* are we inside the extent that was found? */
226 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
227 found_type = btrfs_key_type(&found_key);
228 if (found_key.objectid != inode->i_ino ||
229 found_type != BTRFS_EXTENT_DATA_KEY)
230 goto not_found;
231
232 found_type = btrfs_file_extent_type(leaf, item);
233 extent_start = found_key.offset;
234 if (found_type == BTRFS_FILE_EXTENT_REG) {
235 u64 extent_num_bytes;
236
237 extent_num_bytes = btrfs_file_extent_num_bytes(leaf, item);
238 extent_end = extent_start + extent_num_bytes;
239 err = 0;
240
241 if (loops && start != extent_start)
242 goto not_found;
243
244 if (start < extent_start || start >= extent_end)
245 goto not_found;
246
247 cow_end = min(end, extent_end - 1);
248 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
249 if (bytenr == 0)
250 goto not_found;
251
252 if (btrfs_cross_ref_exists(root, &found_key, bytenr))
253 goto not_found;
254 /*
255 * we may be called by the resizer, make sure we're inside
256 * the limits of the FS
257 */
258 block_group = btrfs_lookup_block_group(root->fs_info,
259 bytenr);
260 if (!block_group || block_group->ro)
261 goto not_found;
262
263 start = extent_end;
264 } else {
265 goto not_found;
266 }
267 loop:
268 if (start > end) {
269 btrfs_free_path(path);
270 return 0;
271 }
272 btrfs_release_path(root, path);
273 loops++;
274 goto again;
275
276 not_found:
277 btrfs_release_path(root, path);
278 cow_file_range(inode, start, end);
279 start = end + 1;
280 goto loop;
281 }
282
283 static int run_delalloc_range(struct inode *inode, u64 start, u64 end)
284 {
285 struct btrfs_root *root = BTRFS_I(inode)->root;
286 int ret;
287
288 if (btrfs_test_opt(root, NODATACOW) ||
289 btrfs_test_flag(inode, NODATACOW))
290 ret = run_delalloc_nocow(inode, start, end);
291 else
292 ret = cow_file_range(inode, start, end);
293
294 return ret;
295 }
296
297 int btrfs_set_bit_hook(struct inode *inode, u64 start, u64 end,
298 unsigned long old, unsigned long bits)
299 {
300 unsigned long flags;
301 if (!(old & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
302 struct btrfs_root *root = BTRFS_I(inode)->root;
303 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
304 BTRFS_I(inode)->delalloc_bytes += end - start + 1;
305 root->fs_info->delalloc_bytes += end - start + 1;
306 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
307 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
308 &root->fs_info->delalloc_inodes);
309 }
310 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
311 }
312 return 0;
313 }
314
315 int btrfs_clear_bit_hook(struct inode *inode, u64 start, u64 end,
316 unsigned long old, unsigned long bits)
317 {
318 if ((old & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
319 struct btrfs_root *root = BTRFS_I(inode)->root;
320 unsigned long flags;
321
322 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
323 if (end - start + 1 > root->fs_info->delalloc_bytes) {
324 printk("warning: delalloc account %Lu %Lu\n",
325 end - start + 1, root->fs_info->delalloc_bytes);
326 root->fs_info->delalloc_bytes = 0;
327 BTRFS_I(inode)->delalloc_bytes = 0;
328 } else {
329 root->fs_info->delalloc_bytes -= end - start + 1;
330 BTRFS_I(inode)->delalloc_bytes -= end - start + 1;
331 }
332 if (BTRFS_I(inode)->delalloc_bytes == 0 &&
333 !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
334 list_del_init(&BTRFS_I(inode)->delalloc_inodes);
335 }
336 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
337 }
338 return 0;
339 }
340
341 int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
342 size_t size, struct bio *bio)
343 {
344 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
345 struct btrfs_mapping_tree *map_tree;
346 u64 logical = bio->bi_sector << 9;
347 u64 length = 0;
348 u64 map_length;
349 int ret;
350
351 length = bio->bi_size;
352 map_tree = &root->fs_info->mapping_tree;
353 map_length = length;
354 ret = btrfs_map_block(map_tree, READ, logical,
355 &map_length, NULL, 0);
356
357 if (map_length < length + size) {
358 return 1;
359 }
360 return 0;
361 }
362
363 int __btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
364 int mirror_num)
365 {
366 struct btrfs_root *root = BTRFS_I(inode)->root;
367 int ret = 0;
368
369 ret = btrfs_csum_one_bio(root, inode, bio);
370 BUG_ON(ret);
371
372 return btrfs_map_bio(root, rw, bio, mirror_num, 1);
373 }
374
375 int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
376 int mirror_num)
377 {
378 struct btrfs_root *root = BTRFS_I(inode)->root;
379 int ret = 0;
380
381 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
382 BUG_ON(ret);
383
384 if (!(rw & (1 << BIO_RW))) {
385 goto mapit;
386 }
387
388 return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
389 inode, rw, bio, mirror_num,
390 __btrfs_submit_bio_hook);
391 mapit:
392 return btrfs_map_bio(root, rw, bio, mirror_num, 0);
393 }
394
395 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
396 struct inode *inode, u64 file_offset,
397 struct list_head *list)
398 {
399 struct list_head *cur;
400 struct btrfs_ordered_sum *sum;
401
402 btrfs_set_trans_block_group(trans, inode);
403 list_for_each(cur, list) {
404 sum = list_entry(cur, struct btrfs_ordered_sum, list);
405 mutex_lock(&BTRFS_I(inode)->csum_mutex);
406 btrfs_csum_file_blocks(trans, BTRFS_I(inode)->root,
407 inode, sum);
408 mutex_unlock(&BTRFS_I(inode)->csum_mutex);
409 }
410 return 0;
411 }
412
413 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end)
414 {
415 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
416 GFP_NOFS);
417 }
418
419 struct btrfs_writepage_fixup {
420 struct page *page;
421 struct btrfs_work work;
422 };
423
424 /* see btrfs_writepage_start_hook for details on why this is required */
425 void btrfs_writepage_fixup_worker(struct btrfs_work *work)
426 {
427 struct btrfs_writepage_fixup *fixup;
428 struct btrfs_ordered_extent *ordered;
429 struct page *page;
430 struct inode *inode;
431 u64 page_start;
432 u64 page_end;
433
434 fixup = container_of(work, struct btrfs_writepage_fixup, work);
435 page = fixup->page;
436 again:
437 lock_page(page);
438 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
439 ClearPageChecked(page);
440 goto out_page;
441 }
442
443 inode = page->mapping->host;
444 page_start = page_offset(page);
445 page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
446
447 lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
448
449 /* already ordered? We're done */
450 if (test_range_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
451 EXTENT_ORDERED, 0)) {
452 goto out;
453 }
454
455 ordered = btrfs_lookup_ordered_extent(inode, page_start);
456 if (ordered) {
457 unlock_extent(&BTRFS_I(inode)->io_tree, page_start,
458 page_end, GFP_NOFS);
459 unlock_page(page);
460 btrfs_start_ordered_extent(inode, ordered, 1);
461 goto again;
462 }
463
464 btrfs_set_extent_delalloc(inode, page_start, page_end);
465 ClearPageChecked(page);
466 out:
467 unlock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
468 out_page:
469 unlock_page(page);
470 page_cache_release(page);
471 }
472
473 /*
474 * There are a few paths in the higher layers of the kernel that directly
475 * set the page dirty bit without asking the filesystem if it is a
476 * good idea. This causes problems because we want to make sure COW
477 * properly happens and the data=ordered rules are followed.
478 *
479 * In our case any range that doesn't have the EXTENT_ORDERED bit set
480 * hasn't been properly setup for IO. We kick off an async process
481 * to fix it up. The async helper will wait for ordered extents, set
482 * the delalloc bit and make it safe to write the page.
483 */
484 int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
485 {
486 struct inode *inode = page->mapping->host;
487 struct btrfs_writepage_fixup *fixup;
488 struct btrfs_root *root = BTRFS_I(inode)->root;
489 int ret;
490
491 ret = test_range_bit(&BTRFS_I(inode)->io_tree, start, end,
492 EXTENT_ORDERED, 0);
493 if (ret)
494 return 0;
495
496 if (PageChecked(page))
497 return -EAGAIN;
498
499 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
500 if (!fixup)
501 return -EAGAIN;
502
503 SetPageChecked(page);
504 page_cache_get(page);
505 fixup->work.func = btrfs_writepage_fixup_worker;
506 fixup->page = page;
507 btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
508 return -EAGAIN;
509 }
510
511 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
512 {
513 struct btrfs_root *root = BTRFS_I(inode)->root;
514 struct btrfs_trans_handle *trans;
515 struct btrfs_ordered_extent *ordered_extent;
516 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
517 u64 alloc_hint = 0;
518 struct list_head list;
519 struct btrfs_key ins;
520 int ret;
521
522 ret = btrfs_dec_test_ordered_pending(inode, start, end - start + 1);
523 if (!ret)
524 return 0;
525
526 trans = btrfs_join_transaction(root, 1);
527
528 ordered_extent = btrfs_lookup_ordered_extent(inode, start);
529 BUG_ON(!ordered_extent);
530
531 lock_extent(io_tree, ordered_extent->file_offset,
532 ordered_extent->file_offset + ordered_extent->len - 1,
533 GFP_NOFS);
534
535 INIT_LIST_HEAD(&list);
536
537 ins.objectid = ordered_extent->start;
538 ins.offset = ordered_extent->len;
539 ins.type = BTRFS_EXTENT_ITEM_KEY;
540
541 ret = btrfs_alloc_reserved_extent(trans, root, root->root_key.objectid,
542 trans->transid, inode->i_ino,
543 ordered_extent->file_offset, &ins);
544 BUG_ON(ret);
545
546 mutex_lock(&BTRFS_I(inode)->extent_mutex);
547
548 ret = btrfs_drop_extents(trans, root, inode,
549 ordered_extent->file_offset,
550 ordered_extent->file_offset +
551 ordered_extent->len,
552 ordered_extent->file_offset, &alloc_hint);
553 BUG_ON(ret);
554 ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
555 ordered_extent->file_offset,
556 ordered_extent->start,
557 ordered_extent->len,
558 ordered_extent->len, 0);
559 BUG_ON(ret);
560
561 btrfs_drop_extent_cache(inode, ordered_extent->file_offset,
562 ordered_extent->file_offset +
563 ordered_extent->len - 1);
564 mutex_unlock(&BTRFS_I(inode)->extent_mutex);
565
566 inode->i_blocks += ordered_extent->len >> 9;
567 unlock_extent(io_tree, ordered_extent->file_offset,
568 ordered_extent->file_offset + ordered_extent->len - 1,
569 GFP_NOFS);
570 add_pending_csums(trans, inode, ordered_extent->file_offset,
571 &ordered_extent->list);
572
573 btrfs_ordered_update_i_size(inode, ordered_extent);
574 btrfs_remove_ordered_extent(inode, ordered_extent);
575
576 /* once for us */
577 btrfs_put_ordered_extent(ordered_extent);
578 /* once for the tree */
579 btrfs_put_ordered_extent(ordered_extent);
580
581 btrfs_update_inode(trans, root, inode);
582 btrfs_end_transaction(trans, root);
583 return 0;
584 }
585
586 int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
587 struct extent_state *state, int uptodate)
588 {
589 return btrfs_finish_ordered_io(page->mapping->host, start, end);
590 }
591
592 int btrfs_readpage_io_hook(struct page *page, u64 start, u64 end)
593 {
594 int ret = 0;
595 struct inode *inode = page->mapping->host;
596 struct btrfs_root *root = BTRFS_I(inode)->root;
597 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
598 struct btrfs_csum_item *item;
599 struct btrfs_path *path = NULL;
600 u32 csum;
601
602 if (btrfs_test_opt(root, NODATASUM) ||
603 btrfs_test_flag(inode, NODATASUM))
604 return 0;
605
606 /*
607 * It is possible there is an ordered extent that has
608 * not yet finished for this range in the file. If so,
609 * that extent will have a csum cached, and it will insert
610 * the sum after all the blocks in the extent are fully
611 * on disk. So, look for an ordered extent and use the
612 * sum if found. We have to do this before looking in the
613 * btree because csum items are pre-inserted based on
614 * the file size. btrfs_lookup_csum might find an item
615 * that still hasn't been fully filled.
616 */
617 ret = btrfs_find_ordered_sum(inode, start, &csum);
618 if (ret == 0)
619 goto found;
620
621 ret = 0;
622 path = btrfs_alloc_path();
623 item = btrfs_lookup_csum(NULL, root, path, inode->i_ino, start, 0);
624 if (IS_ERR(item)) {
625 ret = PTR_ERR(item);
626 /* a csum that isn't present is a preallocated region. */
627 if (ret == -ENOENT || ret == -EFBIG)
628 ret = 0;
629 csum = 0;
630 printk("no csum found for inode %lu start %Lu\n", inode->i_ino,
631 start);
632 goto out;
633 }
634 read_extent_buffer(path->nodes[0], &csum, (unsigned long)item,
635 BTRFS_CRC32_SIZE);
636 found:
637 set_state_private(io_tree, start, csum);
638 out:
639 if (path)
640 btrfs_free_path(path);
641 return ret;
642 }
643
644 struct io_failure_record {
645 struct page *page;
646 u64 start;
647 u64 len;
648 u64 logical;
649 int last_mirror;
650 };
651
652 int btrfs_io_failed_hook(struct bio *failed_bio,
653 struct page *page, u64 start, u64 end,
654 struct extent_state *state)
655 {
656 struct io_failure_record *failrec = NULL;
657 u64 private;
658 struct extent_map *em;
659 struct inode *inode = page->mapping->host;
660 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
661 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
662 struct bio *bio;
663 int num_copies;
664 int ret;
665 int rw;
666 u64 logical;
667
668 ret = get_state_private(failure_tree, start, &private);
669 if (ret) {
670 failrec = kmalloc(sizeof(*failrec), GFP_NOFS);
671 if (!failrec)
672 return -ENOMEM;
673 failrec->start = start;
674 failrec->len = end - start + 1;
675 failrec->last_mirror = 0;
676
677 spin_lock(&em_tree->lock);
678 em = lookup_extent_mapping(em_tree, start, failrec->len);
679 if (em->start > start || em->start + em->len < start) {
680 free_extent_map(em);
681 em = NULL;
682 }
683 spin_unlock(&em_tree->lock);
684
685 if (!em || IS_ERR(em)) {
686 kfree(failrec);
687 return -EIO;
688 }
689 logical = start - em->start;
690 logical = em->block_start + logical;
691 failrec->logical = logical;
692 free_extent_map(em);
693 set_extent_bits(failure_tree, start, end, EXTENT_LOCKED |
694 EXTENT_DIRTY, GFP_NOFS);
695 set_state_private(failure_tree, start,
696 (u64)(unsigned long)failrec);
697 } else {
698 failrec = (struct io_failure_record *)(unsigned long)private;
699 }
700 num_copies = btrfs_num_copies(
701 &BTRFS_I(inode)->root->fs_info->mapping_tree,
702 failrec->logical, failrec->len);
703 failrec->last_mirror++;
704 if (!state) {
705 spin_lock_irq(&BTRFS_I(inode)->io_tree.lock);
706 state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree,
707 failrec->start,
708 EXTENT_LOCKED);
709 if (state && state->start != failrec->start)
710 state = NULL;
711 spin_unlock_irq(&BTRFS_I(inode)->io_tree.lock);
712 }
713 if (!state || failrec->last_mirror > num_copies) {
714 set_state_private(failure_tree, failrec->start, 0);
715 clear_extent_bits(failure_tree, failrec->start,
716 failrec->start + failrec->len - 1,
717 EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
718 kfree(failrec);
719 return -EIO;
720 }
721 bio = bio_alloc(GFP_NOFS, 1);
722 bio->bi_private = state;
723 bio->bi_end_io = failed_bio->bi_end_io;
724 bio->bi_sector = failrec->logical >> 9;
725 bio->bi_bdev = failed_bio->bi_bdev;
726 bio->bi_size = 0;
727 bio_add_page(bio, page, failrec->len, start - page_offset(page));
728 if (failed_bio->bi_rw & (1 << BIO_RW))
729 rw = WRITE;
730 else
731 rw = READ;
732
733 BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio,
734 failrec->last_mirror);
735 return 0;
736 }
737
738 int btrfs_clean_io_failures(struct inode *inode, u64 start)
739 {
740 u64 private;
741 u64 private_failure;
742 struct io_failure_record *failure;
743 int ret;
744
745 private = 0;
746 if (count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
747 (u64)-1, 1, EXTENT_DIRTY)) {
748 ret = get_state_private(&BTRFS_I(inode)->io_failure_tree,
749 start, &private_failure);
750 if (ret == 0) {
751 failure = (struct io_failure_record *)(unsigned long)
752 private_failure;
753 set_state_private(&BTRFS_I(inode)->io_failure_tree,
754 failure->start, 0);
755 clear_extent_bits(&BTRFS_I(inode)->io_failure_tree,
756 failure->start,
757 failure->start + failure->len - 1,
758 EXTENT_DIRTY | EXTENT_LOCKED,
759 GFP_NOFS);
760 kfree(failure);
761 }
762 }
763 return 0;
764 }
765
766 int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
767 struct extent_state *state)
768 {
769 size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
770 struct inode *inode = page->mapping->host;
771 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
772 char *kaddr;
773 u64 private = ~(u32)0;
774 int ret;
775 struct btrfs_root *root = BTRFS_I(inode)->root;
776 u32 csum = ~(u32)0;
777 unsigned long flags;
778
779 if (btrfs_test_opt(root, NODATASUM) ||
780 btrfs_test_flag(inode, NODATASUM))
781 return 0;
782 if (state && state->start == start) {
783 private = state->private;
784 ret = 0;
785 } else {
786 ret = get_state_private(io_tree, start, &private);
787 }
788 local_irq_save(flags);
789 kaddr = kmap_atomic(page, KM_IRQ0);
790 if (ret) {
791 goto zeroit;
792 }
793 csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1);
794 btrfs_csum_final(csum, (char *)&csum);
795 if (csum != private) {
796 goto zeroit;
797 }
798 kunmap_atomic(kaddr, KM_IRQ0);
799 local_irq_restore(flags);
800
801 /* if the io failure tree for this inode is non-empty,
802 * check to see if we've recovered from a failed IO
803 */
804 btrfs_clean_io_failures(inode, start);
805 return 0;
806
807 zeroit:
808 printk("btrfs csum failed ino %lu off %llu csum %u private %Lu\n",
809 page->mapping->host->i_ino, (unsigned long long)start, csum,
810 private);
811 memset(kaddr + offset, 1, end - start + 1);
812 flush_dcache_page(page);
813 kunmap_atomic(kaddr, KM_IRQ0);
814 local_irq_restore(flags);
815 if (private == 0)
816 return 0;
817 return -EIO;
818 }
819
820 /*
821 * This creates an orphan entry for the given inode in case something goes
822 * wrong in the middle of an unlink/truncate.
823 */
824 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
825 {
826 struct btrfs_root *root = BTRFS_I(inode)->root;
827 int ret = 0;
828
829 spin_lock(&root->list_lock);
830
831 /* already on the orphan list, we're good */
832 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
833 spin_unlock(&root->list_lock);
834 return 0;
835 }
836
837 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
838
839 spin_unlock(&root->list_lock);
840
841 /*
842 * insert an orphan item to track this unlinked/truncated file
843 */
844 ret = btrfs_insert_orphan_item(trans, root, inode->i_ino);
845
846 return ret;
847 }
848
849 /*
850 * We have done the truncate/delete so we can go ahead and remove the orphan
851 * item for this particular inode.
852 */
853 int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode)
854 {
855 struct btrfs_root *root = BTRFS_I(inode)->root;
856 int ret = 0;
857
858 spin_lock(&root->list_lock);
859
860 if (list_empty(&BTRFS_I(inode)->i_orphan)) {
861 spin_unlock(&root->list_lock);
862 return 0;
863 }
864
865 list_del_init(&BTRFS_I(inode)->i_orphan);
866 if (!trans) {
867 spin_unlock(&root->list_lock);
868 return 0;
869 }
870
871 spin_unlock(&root->list_lock);
872
873 ret = btrfs_del_orphan_item(trans, root, inode->i_ino);
874
875 return ret;
876 }
877
878 /*
879 * this cleans up any orphans that may be left on the list from the last use
880 * of this root.
881 */
882 void btrfs_orphan_cleanup(struct btrfs_root *root)
883 {
884 struct btrfs_path *path;
885 struct extent_buffer *leaf;
886 struct btrfs_item *item;
887 struct btrfs_key key, found_key;
888 struct btrfs_trans_handle *trans;
889 struct inode *inode;
890 int ret = 0, nr_unlink = 0, nr_truncate = 0;
891
892 /* don't do orphan cleanup if the fs is readonly. */
893 if (root->inode->i_sb->s_flags & MS_RDONLY)
894 return;
895
896 path = btrfs_alloc_path();
897 if (!path)
898 return;
899 path->reada = -1;
900
901 key.objectid = BTRFS_ORPHAN_OBJECTID;
902 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
903 key.offset = (u64)-1;
904
905 trans = btrfs_start_transaction(root, 1);
906 btrfs_set_trans_block_group(trans, root->inode);
907
908 while (1) {
909 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
910 if (ret < 0) {
911 printk(KERN_ERR "Error searching slot for orphan: %d"
912 "\n", ret);
913 break;
914 }
915
916 /*
917 * if ret == 0 means we found what we were searching for, which
918 * is weird, but possible, so only screw with path if we didnt
919 * find the key and see if we have stuff that matches
920 */
921 if (ret > 0) {
922 if (path->slots[0] == 0)
923 break;
924 path->slots[0]--;
925 }
926
927 /* pull out the item */
928 leaf = path->nodes[0];
929 item = btrfs_item_nr(leaf, path->slots[0]);
930 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
931
932 /* make sure the item matches what we want */
933 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
934 break;
935 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
936 break;
937
938 /* release the path since we're done with it */
939 btrfs_release_path(root, path);
940
941 /*
942 * this is where we are basically btrfs_lookup, without the
943 * crossing root thing. we store the inode number in the
944 * offset of the orphan item.
945 */
946 inode = btrfs_iget_locked(root->inode->i_sb,
947 found_key.offset, root);
948 if (!inode)
949 break;
950
951 if (inode->i_state & I_NEW) {
952 BTRFS_I(inode)->root = root;
953
954 /* have to set the location manually */
955 BTRFS_I(inode)->location.objectid = inode->i_ino;
956 BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
957 BTRFS_I(inode)->location.offset = 0;
958
959 btrfs_read_locked_inode(inode);
960 unlock_new_inode(inode);
961 }
962
963 /*
964 * add this inode to the orphan list so btrfs_orphan_del does
965 * the proper thing when we hit it
966 */
967 spin_lock(&root->list_lock);
968 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
969 spin_unlock(&root->list_lock);
970
971 /*
972 * if this is a bad inode, means we actually succeeded in
973 * removing the inode, but not the orphan record, which means
974 * we need to manually delete the orphan since iput will just
975 * do a destroy_inode
976 */
977 if (is_bad_inode(inode)) {
978 btrfs_orphan_del(trans, inode);
979 iput(inode);
980 continue;
981 }
982
983 /* if we have links, this was a truncate, lets do that */
984 if (inode->i_nlink) {
985 nr_truncate++;
986 btrfs_truncate(inode);
987 } else {
988 nr_unlink++;
989 }
990
991 /* this will do delete_inode and everything for us */
992 iput(inode);
993 }
994
995 if (nr_unlink)
996 printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink);
997 if (nr_truncate)
998 printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate);
999
1000 btrfs_free_path(path);
1001 btrfs_end_transaction(trans, root);
1002 }
1003
1004 void btrfs_read_locked_inode(struct inode *inode)
1005 {
1006 struct btrfs_path *path;
1007 struct extent_buffer *leaf;
1008 struct btrfs_inode_item *inode_item;
1009 struct btrfs_timespec *tspec;
1010 struct btrfs_root *root = BTRFS_I(inode)->root;
1011 struct btrfs_key location;
1012 u64 alloc_group_block;
1013 u32 rdev;
1014 int ret;
1015
1016 path = btrfs_alloc_path();
1017 BUG_ON(!path);
1018 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
1019
1020 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
1021 if (ret)
1022 goto make_bad;
1023
1024 leaf = path->nodes[0];
1025 inode_item = btrfs_item_ptr(leaf, path->slots[0],
1026 struct btrfs_inode_item);
1027
1028 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
1029 inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
1030 inode->i_uid = btrfs_inode_uid(leaf, inode_item);
1031 inode->i_gid = btrfs_inode_gid(leaf, inode_item);
1032 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
1033
1034 tspec = btrfs_inode_atime(inode_item);
1035 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
1036 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
1037
1038 tspec = btrfs_inode_mtime(inode_item);
1039 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
1040 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
1041
1042 tspec = btrfs_inode_ctime(inode_item);
1043 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
1044 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
1045
1046 inode->i_blocks = btrfs_inode_nblocks(leaf, inode_item);
1047 inode->i_generation = btrfs_inode_generation(leaf, inode_item);
1048 inode->i_rdev = 0;
1049 rdev = btrfs_inode_rdev(leaf, inode_item);
1050
1051 BTRFS_I(inode)->index_cnt = (u64)-1;
1052
1053 alloc_group_block = btrfs_inode_block_group(leaf, inode_item);
1054 BTRFS_I(inode)->block_group = btrfs_lookup_block_group(root->fs_info,
1055 alloc_group_block);
1056 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
1057 if (!BTRFS_I(inode)->block_group) {
1058 BTRFS_I(inode)->block_group = btrfs_find_block_group(root,
1059 NULL, 0,
1060 BTRFS_BLOCK_GROUP_METADATA, 0);
1061 }
1062 btrfs_free_path(path);
1063 inode_item = NULL;
1064
1065 switch (inode->i_mode & S_IFMT) {
1066 case S_IFREG:
1067 inode->i_mapping->a_ops = &btrfs_aops;
1068 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
1069 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
1070 inode->i_fop = &btrfs_file_operations;
1071 inode->i_op = &btrfs_file_inode_operations;
1072 break;
1073 case S_IFDIR:
1074 inode->i_fop = &btrfs_dir_file_operations;
1075 if (root == root->fs_info->tree_root)
1076 inode->i_op = &btrfs_dir_ro_inode_operations;
1077 else
1078 inode->i_op = &btrfs_dir_inode_operations;
1079 break;
1080 case S_IFLNK:
1081 inode->i_op = &btrfs_symlink_inode_operations;
1082 inode->i_mapping->a_ops = &btrfs_symlink_aops;
1083 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
1084 break;
1085 default:
1086 init_special_inode(inode, inode->i_mode, rdev);
1087 break;
1088 }
1089 return;
1090
1091 make_bad:
1092 btrfs_free_path(path);
1093 make_bad_inode(inode);
1094 }
1095
1096 static void fill_inode_item(struct extent_buffer *leaf,
1097 struct btrfs_inode_item *item,
1098 struct inode *inode)
1099 {
1100 btrfs_set_inode_uid(leaf, item, inode->i_uid);
1101 btrfs_set_inode_gid(leaf, item, inode->i_gid);
1102 btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size);
1103 btrfs_set_inode_mode(leaf, item, inode->i_mode);
1104 btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
1105
1106 btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
1107 inode->i_atime.tv_sec);
1108 btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
1109 inode->i_atime.tv_nsec);
1110
1111 btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
1112 inode->i_mtime.tv_sec);
1113 btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
1114 inode->i_mtime.tv_nsec);
1115
1116 btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
1117 inode->i_ctime.tv_sec);
1118 btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
1119 inode->i_ctime.tv_nsec);
1120
1121 btrfs_set_inode_nblocks(leaf, item, inode->i_blocks);
1122 btrfs_set_inode_generation(leaf, item, inode->i_generation);
1123 btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
1124 btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
1125 btrfs_set_inode_block_group(leaf, item,
1126 BTRFS_I(inode)->block_group->key.objectid);
1127 }
1128
1129 int noinline btrfs_update_inode(struct btrfs_trans_handle *trans,
1130 struct btrfs_root *root,
1131 struct inode *inode)
1132 {
1133 struct btrfs_inode_item *inode_item;
1134 struct btrfs_path *path;
1135 struct extent_buffer *leaf;
1136 int ret;
1137
1138 path = btrfs_alloc_path();
1139 BUG_ON(!path);
1140 ret = btrfs_lookup_inode(trans, root, path,
1141 &BTRFS_I(inode)->location, 1);
1142 if (ret) {
1143 if (ret > 0)
1144 ret = -ENOENT;
1145 goto failed;
1146 }
1147
1148 leaf = path->nodes[0];
1149 inode_item = btrfs_item_ptr(leaf, path->slots[0],
1150 struct btrfs_inode_item);
1151
1152 fill_inode_item(leaf, inode_item, inode);
1153 btrfs_mark_buffer_dirty(leaf);
1154 btrfs_set_inode_last_trans(trans, inode);
1155 ret = 0;
1156 failed:
1157 btrfs_free_path(path);
1158 return ret;
1159 }
1160
1161
1162 static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
1163 struct btrfs_root *root,
1164 struct inode *dir,
1165 struct dentry *dentry)
1166 {
1167 struct btrfs_path *path;
1168 const char *name = dentry->d_name.name;
1169 int name_len = dentry->d_name.len;
1170 int ret = 0;
1171 struct extent_buffer *leaf;
1172 struct btrfs_dir_item *di;
1173 struct btrfs_key key;
1174 u64 index;
1175
1176 path = btrfs_alloc_path();
1177 if (!path) {
1178 ret = -ENOMEM;
1179 goto err;
1180 }
1181
1182 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
1183 name, name_len, -1);
1184 if (IS_ERR(di)) {
1185 ret = PTR_ERR(di);
1186 goto err;
1187 }
1188 if (!di) {
1189 ret = -ENOENT;
1190 goto err;
1191 }
1192 leaf = path->nodes[0];
1193 btrfs_dir_item_key_to_cpu(leaf, di, &key);
1194 ret = btrfs_delete_one_dir_name(trans, root, path, di);
1195 if (ret)
1196 goto err;
1197 btrfs_release_path(root, path);
1198
1199 ret = btrfs_del_inode_ref(trans, root, name, name_len,
1200 dentry->d_inode->i_ino,
1201 dentry->d_parent->d_inode->i_ino, &index);
1202 if (ret) {
1203 printk("failed to delete reference to %.*s, "
1204 "inode %lu parent %lu\n", name_len, name,
1205 dentry->d_inode->i_ino,
1206 dentry->d_parent->d_inode->i_ino);
1207 goto err;
1208 }
1209
1210 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
1211 index, name, name_len, -1);
1212 if (IS_ERR(di)) {
1213 ret = PTR_ERR(di);
1214 goto err;
1215 }
1216 if (!di) {
1217 ret = -ENOENT;
1218 goto err;
1219 }
1220 ret = btrfs_delete_one_dir_name(trans, root, path, di);
1221 btrfs_release_path(root, path);
1222
1223 dentry->d_inode->i_ctime = dir->i_ctime;
1224 err:
1225 btrfs_free_path(path);
1226 if (!ret) {
1227 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
1228 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
1229 btrfs_update_inode(trans, root, dir);
1230 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
1231 dentry->d_inode->i_nlink--;
1232 #else
1233 drop_nlink(dentry->d_inode);
1234 #endif
1235 ret = btrfs_update_inode(trans, root, dentry->d_inode);
1236 dir->i_sb->s_dirt = 1;
1237 }
1238 return ret;
1239 }
1240
1241 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
1242 {
1243 struct btrfs_root *root;
1244 struct btrfs_trans_handle *trans;
1245 struct inode *inode = dentry->d_inode;
1246 int ret;
1247 unsigned long nr = 0;
1248
1249 root = BTRFS_I(dir)->root;
1250
1251 ret = btrfs_check_free_space(root, 1, 1);
1252 if (ret)
1253 goto fail;
1254
1255 trans = btrfs_start_transaction(root, 1);
1256
1257 btrfs_set_trans_block_group(trans, dir);
1258 ret = btrfs_unlink_trans(trans, root, dir, dentry);
1259
1260 if (inode->i_nlink == 0)
1261 ret = btrfs_orphan_add(trans, inode);
1262
1263 nr = trans->blocks_used;
1264
1265 btrfs_end_transaction_throttle(trans, root);
1266 fail:
1267 btrfs_btree_balance_dirty(root, nr);
1268 return ret;
1269 }
1270
1271 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
1272 {
1273 struct inode *inode = dentry->d_inode;
1274 int err = 0;
1275 int ret;
1276 struct btrfs_root *root = BTRFS_I(dir)->root;
1277 struct btrfs_trans_handle *trans;
1278 unsigned long nr = 0;
1279
1280 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
1281 return -ENOTEMPTY;
1282 }
1283
1284 ret = btrfs_check_free_space(root, 1, 1);
1285 if (ret)
1286 goto fail;
1287
1288 trans = btrfs_start_transaction(root, 1);
1289 btrfs_set_trans_block_group(trans, dir);
1290
1291 err = btrfs_orphan_add(trans, inode);
1292 if (err)
1293 goto fail_trans;
1294
1295 /* now the directory is empty */
1296 err = btrfs_unlink_trans(trans, root, dir, dentry);
1297 if (!err) {
1298 btrfs_i_size_write(inode, 0);
1299 }
1300
1301 fail_trans:
1302 nr = trans->blocks_used;
1303 ret = btrfs_end_transaction_throttle(trans, root);
1304 fail:
1305 btrfs_btree_balance_dirty(root, nr);
1306
1307 if (ret && !err)
1308 err = ret;
1309 return err;
1310 }
1311
1312 /*
1313 * this can truncate away extent items, csum items and directory items.
1314 * It starts at a high offset and removes keys until it can't find
1315 * any higher than i_size.
1316 *
1317 * csum items that cross the new i_size are truncated to the new size
1318 * as well.
1319 *
1320 * min_type is the minimum key type to truncate down to. If set to 0, this
1321 * will kill all the items on this inode, including the INODE_ITEM_KEY.
1322 */
1323 static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
1324 struct btrfs_root *root,
1325 struct inode *inode,
1326 u32 min_type)
1327 {
1328 int ret;
1329 struct btrfs_path *path;
1330 struct btrfs_key key;
1331 struct btrfs_key found_key;
1332 u32 found_type;
1333 struct extent_buffer *leaf;
1334 struct btrfs_file_extent_item *fi;
1335 u64 extent_start = 0;
1336 u64 extent_num_bytes = 0;
1337 u64 item_end = 0;
1338 u64 root_gen = 0;
1339 u64 root_owner = 0;
1340 int found_extent;
1341 int del_item;
1342 int pending_del_nr = 0;
1343 int pending_del_slot = 0;
1344 int extent_type = -1;
1345 u64 mask = root->sectorsize - 1;
1346
1347 btrfs_drop_extent_cache(inode, inode->i_size & (~mask), (u64)-1);
1348 path = btrfs_alloc_path();
1349 path->reada = -1;
1350 BUG_ON(!path);
1351
1352 /* FIXME, add redo link to tree so we don't leak on crash */
1353 key.objectid = inode->i_ino;
1354 key.offset = (u64)-1;
1355 key.type = (u8)-1;
1356
1357 btrfs_init_path(path);
1358 search_again:
1359 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1360 if (ret < 0) {
1361 goto error;
1362 }
1363 if (ret > 0) {
1364 BUG_ON(path->slots[0] == 0);
1365 path->slots[0]--;
1366 }
1367
1368 while(1) {
1369 fi = NULL;
1370 leaf = path->nodes[0];
1371 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1372 found_type = btrfs_key_type(&found_key);
1373
1374 if (found_key.objectid != inode->i_ino)
1375 break;
1376
1377 if (found_type < min_type)
1378 break;
1379
1380 item_end = found_key.offset;
1381 if (found_type == BTRFS_EXTENT_DATA_KEY) {
1382 fi = btrfs_item_ptr(leaf, path->slots[0],
1383 struct btrfs_file_extent_item);
1384 extent_type = btrfs_file_extent_type(leaf, fi);
1385 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
1386 item_end +=
1387 btrfs_file_extent_num_bytes(leaf, fi);
1388 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1389 struct btrfs_item *item = btrfs_item_nr(leaf,
1390 path->slots[0]);
1391 item_end += btrfs_file_extent_inline_len(leaf,
1392 item);
1393 }
1394 item_end--;
1395 }
1396 if (found_type == BTRFS_CSUM_ITEM_KEY) {
1397 ret = btrfs_csum_truncate(trans, root, path,
1398 inode->i_size);
1399 BUG_ON(ret);
1400 }
1401 if (item_end < inode->i_size) {
1402 if (found_type == BTRFS_DIR_ITEM_KEY) {
1403 found_type = BTRFS_INODE_ITEM_KEY;
1404 } else if (found_type == BTRFS_EXTENT_ITEM_KEY) {
1405 found_type = BTRFS_CSUM_ITEM_KEY;
1406 } else if (found_type == BTRFS_EXTENT_DATA_KEY) {
1407 found_type = BTRFS_XATTR_ITEM_KEY;
1408 } else if (found_type == BTRFS_XATTR_ITEM_KEY) {
1409 found_type = BTRFS_INODE_REF_KEY;
1410 } else if (found_type) {
1411 found_type--;
1412 } else {
1413 break;
1414 }
1415 btrfs_set_key_type(&key, found_type);
1416 goto next;
1417 }
1418 if (found_key.offset >= inode->i_size)
1419 del_item = 1;
1420 else
1421 del_item = 0;
1422 found_extent = 0;
1423
1424 /* FIXME, shrink the extent if the ref count is only 1 */
1425 if (found_type != BTRFS_EXTENT_DATA_KEY)
1426 goto delete;
1427
1428 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
1429 u64 num_dec;
1430 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
1431 if (!del_item) {
1432 u64 orig_num_bytes =
1433 btrfs_file_extent_num_bytes(leaf, fi);
1434 extent_num_bytes = inode->i_size -
1435 found_key.offset + root->sectorsize - 1;
1436 extent_num_bytes = extent_num_bytes &
1437 ~((u64)root->sectorsize - 1);
1438 btrfs_set_file_extent_num_bytes(leaf, fi,
1439 extent_num_bytes);
1440 num_dec = (orig_num_bytes -
1441 extent_num_bytes);
1442 if (extent_start != 0)
1443 dec_i_blocks(inode, num_dec);
1444 btrfs_mark_buffer_dirty(leaf);
1445 } else {
1446 extent_num_bytes =
1447 btrfs_file_extent_disk_num_bytes(leaf,
1448 fi);
1449 /* FIXME blocksize != 4096 */
1450 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
1451 if (extent_start != 0) {
1452 found_extent = 1;
1453 dec_i_blocks(inode, num_dec);
1454 }
1455 root_gen = btrfs_header_generation(leaf);
1456 root_owner = btrfs_header_owner(leaf);
1457 }
1458 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1459 if (!del_item) {
1460 u32 newsize = inode->i_size - found_key.offset;
1461 dec_i_blocks(inode, item_end + 1 -
1462 found_key.offset - newsize);
1463 newsize =
1464 btrfs_file_extent_calc_inline_size(newsize);
1465 ret = btrfs_truncate_item(trans, root, path,
1466 newsize, 1);
1467 BUG_ON(ret);
1468 } else {
1469 dec_i_blocks(inode, item_end + 1 -
1470 found_key.offset);
1471 }
1472 }
1473 delete:
1474 if (del_item) {
1475 if (!pending_del_nr) {
1476 /* no pending yet, add ourselves */
1477 pending_del_slot = path->slots[0];
1478 pending_del_nr = 1;
1479 } else if (pending_del_nr &&
1480 path->slots[0] + 1 == pending_del_slot) {
1481 /* hop on the pending chunk */
1482 pending_del_nr++;
1483 pending_del_slot = path->slots[0];
1484 } else {
1485 printk("bad pending slot %d pending_del_nr %d pending_del_slot %d\n", path->slots[0], pending_del_nr, pending_del_slot);
1486 }
1487 } else {
1488 break;
1489 }
1490 if (found_extent) {
1491 ret = btrfs_free_extent(trans, root, extent_start,
1492 extent_num_bytes,
1493 root_owner,
1494 root_gen, inode->i_ino,
1495 found_key.offset, 0);
1496 BUG_ON(ret);
1497 }
1498 next:
1499 if (path->slots[0] == 0) {
1500 if (pending_del_nr)
1501 goto del_pending;
1502 btrfs_release_path(root, path);
1503 goto search_again;
1504 }
1505
1506 path->slots[0]--;
1507 if (pending_del_nr &&
1508 path->slots[0] + 1 != pending_del_slot) {
1509 struct btrfs_key debug;
1510 del_pending:
1511 btrfs_item_key_to_cpu(path->nodes[0], &debug,
1512 pending_del_slot);
1513 ret = btrfs_del_items(trans, root, path,
1514 pending_del_slot,
1515 pending_del_nr);
1516 BUG_ON(ret);
1517 pending_del_nr = 0;
1518 btrfs_release_path(root, path);
1519 goto search_again;
1520 }
1521 }
1522 ret = 0;
1523 error:
1524 if (pending_del_nr) {
1525 ret = btrfs_del_items(trans, root, path, pending_del_slot,
1526 pending_del_nr);
1527 }
1528 btrfs_free_path(path);
1529 inode->i_sb->s_dirt = 1;
1530 return ret;
1531 }
1532
1533 /*
1534 * taken from block_truncate_page, but does cow as it zeros out
1535 * any bytes left in the last page in the file.
1536 */
1537 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
1538 {
1539 struct inode *inode = mapping->host;
1540 struct btrfs_root *root = BTRFS_I(inode)->root;
1541 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1542 struct btrfs_ordered_extent *ordered;
1543 char *kaddr;
1544 u32 blocksize = root->sectorsize;
1545 pgoff_t index = from >> PAGE_CACHE_SHIFT;
1546 unsigned offset = from & (PAGE_CACHE_SIZE-1);
1547 struct page *page;
1548 int ret = 0;
1549 u64 page_start;
1550 u64 page_end;
1551
1552 if ((offset & (blocksize - 1)) == 0)
1553 goto out;
1554
1555 ret = -ENOMEM;
1556 again:
1557 page = grab_cache_page(mapping, index);
1558 if (!page)
1559 goto out;
1560
1561 page_start = page_offset(page);
1562 page_end = page_start + PAGE_CACHE_SIZE - 1;
1563
1564 if (!PageUptodate(page)) {
1565 ret = btrfs_readpage(NULL, page);
1566 lock_page(page);
1567 if (page->mapping != mapping) {
1568 unlock_page(page);
1569 page_cache_release(page);
1570 goto again;
1571 }
1572 if (!PageUptodate(page)) {
1573 ret = -EIO;
1574 goto out_unlock;
1575 }
1576 }
1577 wait_on_page_writeback(page);
1578
1579 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
1580 set_page_extent_mapped(page);
1581
1582 ordered = btrfs_lookup_ordered_extent(inode, page_start);
1583 if (ordered) {
1584 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
1585 unlock_page(page);
1586 page_cache_release(page);
1587 btrfs_start_ordered_extent(inode, ordered, 1);
1588 btrfs_put_ordered_extent(ordered);
1589 goto again;
1590 }
1591
1592 btrfs_set_extent_delalloc(inode, page_start, page_end);
1593 ret = 0;
1594 if (offset != PAGE_CACHE_SIZE) {
1595 kaddr = kmap(page);
1596 memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
1597 flush_dcache_page(page);
1598 kunmap(page);
1599 }
1600 ClearPageChecked(page);
1601 set_page_dirty(page);
1602 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
1603
1604 out_unlock:
1605 unlock_page(page);
1606 page_cache_release(page);
1607 out:
1608 return ret;
1609 }
1610
1611 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
1612 {
1613 struct inode *inode = dentry->d_inode;
1614 int err;
1615
1616 err = inode_change_ok(inode, attr);
1617 if (err)
1618 return err;
1619
1620 if (S_ISREG(inode->i_mode) &&
1621 attr->ia_valid & ATTR_SIZE && attr->ia_size > inode->i_size) {
1622 struct btrfs_trans_handle *trans;
1623 struct btrfs_root *root = BTRFS_I(inode)->root;
1624 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1625
1626 u64 mask = root->sectorsize - 1;
1627 u64 hole_start = (inode->i_size + mask) & ~mask;
1628 u64 block_end = (attr->ia_size + mask) & ~mask;
1629 u64 hole_size;
1630 u64 alloc_hint = 0;
1631
1632 if (attr->ia_size <= hole_start)
1633 goto out;
1634
1635 err = btrfs_check_free_space(root, 1, 0);
1636 if (err)
1637 goto fail;
1638
1639 btrfs_truncate_page(inode->i_mapping, inode->i_size);
1640
1641 hole_size = block_end - hole_start;
1642 btrfs_wait_ordered_range(inode, hole_start, hole_size);
1643 lock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
1644
1645 trans = btrfs_start_transaction(root, 1);
1646 btrfs_set_trans_block_group(trans, inode);
1647 mutex_lock(&BTRFS_I(inode)->extent_mutex);
1648 err = btrfs_drop_extents(trans, root, inode,
1649 hole_start, block_end, hole_start,
1650 &alloc_hint);
1651
1652 if (alloc_hint != EXTENT_MAP_INLINE) {
1653 err = btrfs_insert_file_extent(trans, root,
1654 inode->i_ino,
1655 hole_start, 0, 0,
1656 hole_size, 0);
1657 btrfs_drop_extent_cache(inode, hole_start,
1658 (u64)-1);
1659 btrfs_check_file(root, inode);
1660 }
1661 mutex_unlock(&BTRFS_I(inode)->extent_mutex);
1662 btrfs_end_transaction(trans, root);
1663 unlock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
1664 if (err)
1665 return err;
1666 }
1667 out:
1668 err = inode_setattr(inode, attr);
1669
1670 if (!err && ((attr->ia_valid & ATTR_MODE)))
1671 err = btrfs_acl_chmod(inode);
1672 fail:
1673 return err;
1674 }
1675
1676 void btrfs_delete_inode(struct inode *inode)
1677 {
1678 struct btrfs_trans_handle *trans;
1679 struct btrfs_root *root = BTRFS_I(inode)->root;
1680 unsigned long nr;
1681 int ret;
1682
1683 truncate_inode_pages(&inode->i_data, 0);
1684 if (is_bad_inode(inode)) {
1685 btrfs_orphan_del(NULL, inode);
1686 goto no_delete;
1687 }
1688 btrfs_wait_ordered_range(inode, 0, (u64)-1);
1689
1690 btrfs_i_size_write(inode, 0);
1691 trans = btrfs_start_transaction(root, 1);
1692
1693 btrfs_set_trans_block_group(trans, inode);
1694 ret = btrfs_truncate_in_trans(trans, root, inode, 0);
1695 if (ret) {
1696 btrfs_orphan_del(NULL, inode);
1697 goto no_delete_lock;
1698 }
1699
1700 btrfs_orphan_del(trans, inode);
1701
1702 nr = trans->blocks_used;
1703 clear_inode(inode);
1704
1705 btrfs_end_transaction(trans, root);
1706 btrfs_btree_balance_dirty(root, nr);
1707 return;
1708
1709 no_delete_lock:
1710 nr = trans->blocks_used;
1711 btrfs_end_transaction(trans, root);
1712 btrfs_btree_balance_dirty(root, nr);
1713 no_delete:
1714 clear_inode(inode);
1715 }
1716
1717 /*
1718 * this returns the key found in the dir entry in the location pointer.
1719 * If no dir entries were found, location->objectid is 0.
1720 */
1721 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
1722 struct btrfs_key *location)
1723 {
1724 const char *name = dentry->d_name.name;
1725 int namelen = dentry->d_name.len;
1726 struct btrfs_dir_item *di;
1727 struct btrfs_path *path;
1728 struct btrfs_root *root = BTRFS_I(dir)->root;
1729 int ret = 0;
1730
1731 if (namelen == 1 && strcmp(name, ".") == 0) {
1732 location->objectid = dir->i_ino;
1733 location->type = BTRFS_INODE_ITEM_KEY;
1734 location->offset = 0;
1735 return 0;
1736 }
1737 path = btrfs_alloc_path();
1738 BUG_ON(!path);
1739
1740 if (namelen == 2 && strcmp(name, "..") == 0) {
1741 struct btrfs_key key;
1742 struct extent_buffer *leaf;
1743 int slot;
1744
1745 key.objectid = dir->i_ino;
1746 key.offset = (u64)-1;
1747 btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
1748 if (ret < 0 || path->slots[0] == 0)
1749 goto out_err;
1750 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1751 BUG_ON(ret == 0);
1752 ret = 0;
1753 leaf = path->nodes[0];
1754 slot = path->slots[0] - 1;
1755
1756 btrfs_item_key_to_cpu(leaf, &key, slot);
1757 if (key.objectid != dir->i_ino ||
1758 key.type != BTRFS_INODE_REF_KEY) {
1759 goto out_err;
1760 }
1761 location->objectid = key.offset;
1762 location->type = BTRFS_INODE_ITEM_KEY;
1763 location->offset = 0;
1764 goto out;
1765 }
1766
1767 di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
1768 namelen, 0);
1769 if (IS_ERR(di))
1770 ret = PTR_ERR(di);
1771 if (!di || IS_ERR(di)) {
1772 goto out_err;
1773 }
1774 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
1775 out:
1776 btrfs_free_path(path);
1777 return ret;
1778 out_err:
1779 location->objectid = 0;
1780 goto out;
1781 }
1782
1783 /*
1784 * when we hit a tree root in a directory, the btrfs part of the inode
1785 * needs to be changed to reflect the root directory of the tree root. This
1786 * is kind of like crossing a mount point.
1787 */
1788 static int fixup_tree_root_location(struct btrfs_root *root,
1789 struct btrfs_key *location,
1790 struct btrfs_root **sub_root,
1791 struct dentry *dentry)
1792 {
1793 struct btrfs_root_item *ri;
1794
1795 if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
1796 return 0;
1797 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1798 return 0;
1799
1800 *sub_root = btrfs_read_fs_root(root->fs_info, location,
1801 dentry->d_name.name,
1802 dentry->d_name.len);
1803 if (IS_ERR(*sub_root))
1804 return PTR_ERR(*sub_root);
1805
1806 ri = &(*sub_root)->root_item;
1807 location->objectid = btrfs_root_dirid(ri);
1808 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
1809 location->offset = 0;
1810
1811 return 0;
1812 }
1813
1814 static int btrfs_init_locked_inode(struct inode *inode, void *p)
1815 {
1816 struct btrfs_iget_args *args = p;
1817 inode->i_ino = args->ino;
1818 BTRFS_I(inode)->root = args->root;
1819 BTRFS_I(inode)->delalloc_bytes = 0;
1820 BTRFS_I(inode)->disk_i_size = 0;
1821 BTRFS_I(inode)->index_cnt = (u64)-1;
1822 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
1823 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
1824 inode->i_mapping, GFP_NOFS);
1825 extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
1826 inode->i_mapping, GFP_NOFS);
1827 INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
1828 btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
1829 mutex_init(&BTRFS_I(inode)->csum_mutex);
1830 mutex_init(&BTRFS_I(inode)->extent_mutex);
1831 return 0;
1832 }
1833
1834 static int btrfs_find_actor(struct inode *inode, void *opaque)
1835 {
1836 struct btrfs_iget_args *args = opaque;
1837 return (args->ino == inode->i_ino &&
1838 args->root == BTRFS_I(inode)->root);
1839 }
1840
1841 struct inode *btrfs_ilookup(struct super_block *s, u64 objectid,
1842 u64 root_objectid)
1843 {
1844 struct btrfs_iget_args args;
1845 args.ino = objectid;
1846 args.root = btrfs_lookup_fs_root(btrfs_sb(s)->fs_info, root_objectid);
1847
1848 if (!args.root)
1849 return NULL;
1850
1851 return ilookup5(s, objectid, btrfs_find_actor, (void *)&args);
1852 }
1853
1854 struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
1855 struct btrfs_root *root)
1856 {
1857 struct inode *inode;
1858 struct btrfs_iget_args args;
1859 args.ino = objectid;
1860 args.root = root;
1861
1862 inode = iget5_locked(s, objectid, btrfs_find_actor,
1863 btrfs_init_locked_inode,
1864 (void *)&args);
1865 return inode;
1866 }
1867
1868 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
1869 struct nameidata *nd)
1870 {
1871 struct inode * inode;
1872 struct btrfs_inode *bi = BTRFS_I(dir);
1873 struct btrfs_root *root = bi->root;
1874 struct btrfs_root *sub_root = root;
1875 struct btrfs_key location;
1876 int ret, do_orphan = 0;
1877
1878 if (dentry->d_name.len > BTRFS_NAME_LEN)
1879 return ERR_PTR(-ENAMETOOLONG);
1880
1881 ret = btrfs_inode_by_name(dir, dentry, &location);
1882
1883 if (ret < 0)
1884 return ERR_PTR(ret);
1885
1886 inode = NULL;
1887 if (location.objectid) {
1888 ret = fixup_tree_root_location(root, &location, &sub_root,
1889 dentry);
1890 if (ret < 0)
1891 return ERR_PTR(ret);
1892 if (ret > 0)
1893 return ERR_PTR(-ENOENT);
1894
1895 inode = btrfs_iget_locked(dir->i_sb, location.objectid,
1896 sub_root);
1897 if (!inode)
1898 return ERR_PTR(-EACCES);
1899 if (inode->i_state & I_NEW) {
1900 /* the inode and parent dir are two different roots */
1901 if (sub_root != root) {
1902 igrab(inode);
1903 sub_root->inode = inode;
1904 do_orphan = 1;
1905 }
1906 BTRFS_I(inode)->root = sub_root;
1907 memcpy(&BTRFS_I(inode)->location, &location,
1908 sizeof(location));
1909 btrfs_read_locked_inode(inode);
1910 unlock_new_inode(inode);
1911 }
1912 }
1913
1914 if (unlikely(do_orphan))
1915 btrfs_orphan_cleanup(sub_root);
1916
1917 return d_splice_alias(inode, dentry);
1918 }
1919
1920 static unsigned char btrfs_filetype_table[] = {
1921 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
1922 };
1923
1924 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
1925 {
1926 struct inode *inode = filp->f_dentry->d_inode;
1927 struct btrfs_root *root = BTRFS_I(inode)->root;
1928 struct btrfs_item *item;
1929 struct btrfs_dir_item *di;
1930 struct btrfs_key key;
1931 struct btrfs_key found_key;
1932 struct btrfs_path *path;
1933 int ret;
1934 u32 nritems;
1935 struct extent_buffer *leaf;
1936 int slot;
1937 int advance;
1938 unsigned char d_type;
1939 int over = 0;
1940 u32 di_cur;
1941 u32 di_total;
1942 u32 di_len;
1943 int key_type = BTRFS_DIR_INDEX_KEY;
1944 char tmp_name[32];
1945 char *name_ptr;
1946 int name_len;
1947
1948 /* FIXME, use a real flag for deciding about the key type */
1949 if (root->fs_info->tree_root == root)
1950 key_type = BTRFS_DIR_ITEM_KEY;
1951
1952 /* special case for "." */
1953 if (filp->f_pos == 0) {
1954 over = filldir(dirent, ".", 1,
1955 1, inode->i_ino,
1956 DT_DIR);
1957 if (over)
1958 return 0;
1959 filp->f_pos = 1;
1960 }
1961
1962 key.objectid = inode->i_ino;
1963 path = btrfs_alloc_path();
1964 path->reada = 2;
1965
1966 /* special case for .., just use the back ref */
1967 if (filp->f_pos == 1) {
1968 btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
1969 key.offset = (u64)-1;
1970 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1971 if (ret < 0 || path->slots[0] == 0) {
1972 btrfs_release_path(root, path);
1973 goto read_dir_items;
1974 }
1975 BUG_ON(ret == 0);
1976 leaf = path->nodes[0];
1977 slot = path->slots[0] - 1;
1978 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1979 btrfs_release_path(root, path);
1980 if (found_key.objectid != key.objectid ||
1981 found_key.type != BTRFS_INODE_REF_KEY)
1982 goto read_dir_items;
1983 over = filldir(dirent, "..", 2,
1984 2, found_key.offset, DT_DIR);
1985 if (over)
1986 goto nopos;
1987 filp->f_pos = 2;
1988 }
1989
1990 read_dir_items:
1991 btrfs_set_key_type(&key, key_type);
1992 key.offset = filp->f_pos;
1993
1994 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1995 if (ret < 0)
1996 goto err;
1997 advance = 0;
1998 while(1) {
1999 leaf = path->nodes[0];
2000 nritems = btrfs_header_nritems(leaf);
2001 slot = path->slots[0];
2002 if (advance || slot >= nritems) {
2003 if (slot >= nritems -1) {
2004 ret = btrfs_next_leaf(root, path);
2005 if (ret)
2006 break;
2007 leaf = path->nodes[0];
2008 nritems = btrfs_header_nritems(leaf);
2009 slot = path->slots[0];
2010 } else {
2011 slot++;
2012 path->slots[0]++;
2013 }
2014 }
2015 advance = 1;
2016 item = btrfs_item_nr(leaf, slot);
2017 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2018
2019 if (found_key.objectid != key.objectid)
2020 break;
2021 if (btrfs_key_type(&found_key) != key_type)
2022 break;
2023 if (found_key.offset < filp->f_pos)
2024 continue;
2025
2026 filp->f_pos = found_key.offset;
2027 advance = 1;
2028 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
2029 di_cur = 0;
2030 di_total = btrfs_item_size(leaf, item);
2031 while(di_cur < di_total) {
2032 struct btrfs_key location;
2033
2034 name_len = btrfs_dir_name_len(leaf, di);
2035 if (name_len < 32) {
2036 name_ptr = tmp_name;
2037 } else {
2038 name_ptr = kmalloc(name_len, GFP_NOFS);
2039 BUG_ON(!name_ptr);
2040 }
2041 read_extent_buffer(leaf, name_ptr,
2042 (unsigned long)(di + 1), name_len);
2043
2044 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
2045 btrfs_dir_item_key_to_cpu(leaf, di, &location);
2046 over = filldir(dirent, name_ptr, name_len,
2047 found_key.offset,
2048 location.objectid,
2049 d_type);
2050
2051 if (name_ptr != tmp_name)
2052 kfree(name_ptr);
2053
2054 if (over)
2055 goto nopos;
2056 di_len = btrfs_dir_name_len(leaf, di) +
2057 btrfs_dir_data_len(leaf, di) +sizeof(*di);
2058 di_cur += di_len;
2059 di = (struct btrfs_dir_item *)((char *)di + di_len);
2060 }
2061 }
2062 if (key_type == BTRFS_DIR_INDEX_KEY)
2063 filp->f_pos = INT_LIMIT(typeof(filp->f_pos));
2064 else
2065 filp->f_pos++;
2066 nopos:
2067 ret = 0;
2068 err:
2069 btrfs_free_path(path);
2070 return ret;
2071 }
2072
2073 int btrfs_write_inode(struct inode *inode, int wait)
2074 {
2075 struct btrfs_root *root = BTRFS_I(inode)->root;
2076 struct btrfs_trans_handle *trans;
2077 int ret = 0;
2078
2079 if (wait) {
2080 trans = btrfs_join_transaction(root, 1);
2081 btrfs_set_trans_block_group(trans, inode);
2082 ret = btrfs_commit_transaction(trans, root);
2083 }
2084 return ret;
2085 }
2086
2087 /*
2088 * This is somewhat expensive, updating the tree every time the
2089 * inode changes. But, it is most likely to find the inode in cache.
2090 * FIXME, needs more benchmarking...there are no reasons other than performance
2091 * to keep or drop this code.
2092 */
2093 void btrfs_dirty_inode(struct inode *inode)
2094 {
2095 struct btrfs_root *root = BTRFS_I(inode)->root;
2096 struct btrfs_trans_handle *trans;
2097
2098 trans = btrfs_join_transaction(root, 1);
2099 btrfs_set_trans_block_group(trans, inode);
2100 btrfs_update_inode(trans, root, inode);
2101 btrfs_end_transaction(trans, root);
2102 }
2103
2104 static int btrfs_set_inode_index_count(struct inode *inode)
2105 {
2106 struct btrfs_root *root = BTRFS_I(inode)->root;
2107 struct btrfs_key key, found_key;
2108 struct btrfs_path *path;
2109 struct extent_buffer *leaf;
2110 int ret;
2111
2112 key.objectid = inode->i_ino;
2113 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
2114 key.offset = (u64)-1;
2115
2116 path = btrfs_alloc_path();
2117 if (!path)
2118 return -ENOMEM;
2119
2120 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2121 if (ret < 0)
2122 goto out;
2123 /* FIXME: we should be able to handle this */
2124 if (ret == 0)
2125 goto out;
2126 ret = 0;
2127
2128 /*
2129 * MAGIC NUMBER EXPLANATION:
2130 * since we search a directory based on f_pos we have to start at 2
2131 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
2132 * else has to start at 2
2133 */
2134 if (path->slots[0] == 0) {
2135 BTRFS_I(inode)->index_cnt = 2;
2136 goto out;
2137 }
2138
2139 path->slots[0]--;
2140
2141 leaf = path->nodes[0];
2142 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2143
2144 if (found_key.objectid != inode->i_ino ||
2145 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
2146 BTRFS_I(inode)->index_cnt = 2;
2147 goto out;
2148 }
2149
2150 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
2151 out:
2152 btrfs_free_path(path);
2153 return ret;
2154 }
2155
2156 static int btrfs_set_inode_index(struct inode *dir, struct inode *inode)
2157 {
2158 int ret = 0;
2159
2160 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
2161 ret = btrfs_set_inode_index_count(dir);
2162 if (ret)
2163 return ret;
2164 }
2165
2166 BTRFS_I(inode)->index = BTRFS_I(dir)->index_cnt;
2167 BTRFS_I(dir)->index_cnt++;
2168
2169 return ret;
2170 }
2171
2172 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
2173 struct btrfs_root *root,
2174 struct inode *dir,
2175 const char *name, int name_len,
2176 u64 ref_objectid,
2177 u64 objectid,
2178 struct btrfs_block_group_cache *group,
2179 int mode)
2180 {
2181 struct inode *inode;
2182 struct btrfs_inode_item *inode_item;
2183 struct btrfs_block_group_cache *new_inode_group;
2184 struct btrfs_key *location;
2185 struct btrfs_path *path;
2186 struct btrfs_inode_ref *ref;
2187 struct btrfs_key key[2];
2188 u32 sizes[2];
2189 unsigned long ptr;
2190 int ret;
2191 int owner;
2192
2193 path = btrfs_alloc_path();
2194 BUG_ON(!path);
2195
2196 inode = new_inode(root->fs_info->sb);
2197 if (!inode)
2198 return ERR_PTR(-ENOMEM);
2199
2200 if (dir) {
2201 ret = btrfs_set_inode_index(dir, inode);
2202 if (ret)
2203 return ERR_PTR(ret);
2204 } else {
2205 BTRFS_I(inode)->index = 0;
2206 }
2207 /*
2208 * index_cnt is ignored for everything but a dir,
2209 * btrfs_get_inode_index_count has an explanation for the magic
2210 * number
2211 */
2212 BTRFS_I(inode)->index_cnt = 2;
2213
2214 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
2215 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
2216 inode->i_mapping, GFP_NOFS);
2217 extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
2218 inode->i_mapping, GFP_NOFS);
2219 btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
2220 INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
2221 mutex_init(&BTRFS_I(inode)->csum_mutex);
2222 mutex_init(&BTRFS_I(inode)->extent_mutex);
2223 BTRFS_I(inode)->delalloc_bytes = 0;
2224 BTRFS_I(inode)->disk_i_size = 0;
2225 BTRFS_I(inode)->root = root;
2226
2227 if (mode & S_IFDIR)
2228 owner = 0;
2229 else
2230 owner = 1;
2231 new_inode_group = btrfs_find_block_group(root, group, 0,
2232 BTRFS_BLOCK_GROUP_METADATA, owner);
2233 if (!new_inode_group) {
2234 printk("find_block group failed\n");
2235 new_inode_group = group;
2236 }
2237 BTRFS_I(inode)->block_group = new_inode_group;
2238 BTRFS_I(inode)->flags = 0;
2239
2240 key[0].objectid = objectid;
2241 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
2242 key[0].offset = 0;
2243
2244 key[1].objectid = objectid;
2245 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
2246 key[1].offset = ref_objectid;
2247
2248 sizes[0] = sizeof(struct btrfs_inode_item);
2249 sizes[1] = name_len + sizeof(*ref);
2250
2251 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
2252 if (ret != 0)
2253 goto fail;
2254
2255 if (objectid > root->highest_inode)
2256 root->highest_inode = objectid;
2257
2258 inode->i_uid = current->fsuid;
2259 inode->i_gid = current->fsgid;
2260 inode->i_mode = mode;
2261 inode->i_ino = objectid;
2262 inode->i_blocks = 0;
2263 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
2264 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2265 struct btrfs_inode_item);
2266 fill_inode_item(path->nodes[0], inode_item, inode);
2267
2268 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
2269 struct btrfs_inode_ref);
2270 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
2271 btrfs_set_inode_ref_index(path->nodes[0], ref, BTRFS_I(inode)->index);
2272 ptr = (unsigned long)(ref + 1);
2273 write_extent_buffer(path->nodes[0], name, ptr, name_len);
2274
2275 btrfs_mark_buffer_dirty(path->nodes[0]);
2276 btrfs_free_path(path);
2277
2278 location = &BTRFS_I(inode)->location;
2279 location->objectid = objectid;
2280 location->offset = 0;
2281 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
2282
2283 insert_inode_hash(inode);
2284 return inode;
2285 fail:
2286 if (dir)
2287 BTRFS_I(dir)->index_cnt--;
2288 btrfs_free_path(path);
2289 return ERR_PTR(ret);
2290 }
2291
2292 static inline u8 btrfs_inode_type(struct inode *inode)
2293 {
2294 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
2295 }
2296
2297 static int btrfs_add_link(struct btrfs_trans_handle *trans,
2298 struct dentry *dentry, struct inode *inode,
2299 int add_backref)
2300 {
2301 int ret;
2302 struct btrfs_key key;
2303 struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
2304 struct inode *parent_inode = dentry->d_parent->d_inode;
2305
2306 key.objectid = inode->i_ino;
2307 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
2308 key.offset = 0;
2309
2310 ret = btrfs_insert_dir_item(trans, root,
2311 dentry->d_name.name, dentry->d_name.len,
2312 dentry->d_parent->d_inode->i_ino,
2313 &key, btrfs_inode_type(inode),
2314 BTRFS_I(inode)->index);
2315 if (ret == 0) {
2316 if (add_backref) {
2317 ret = btrfs_insert_inode_ref(trans, root,
2318 dentry->d_name.name,
2319 dentry->d_name.len,
2320 inode->i_ino,
2321 parent_inode->i_ino,
2322 BTRFS_I(inode)->index);
2323 }
2324 btrfs_i_size_write(parent_inode, parent_inode->i_size +
2325 dentry->d_name.len * 2);
2326 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
2327 ret = btrfs_update_inode(trans, root,
2328 dentry->d_parent->d_inode);
2329 }
2330 return ret;
2331 }
2332
2333 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
2334 struct dentry *dentry, struct inode *inode,
2335 int backref)
2336 {
2337 int err = btrfs_add_link(trans, dentry, inode, backref);
2338 if (!err) {
2339 d_instantiate(dentry, inode);
2340 return 0;
2341 }
2342 if (err > 0)
2343 err = -EEXIST;
2344 return err;
2345 }
2346
2347 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
2348 int mode, dev_t rdev)
2349 {
2350 struct btrfs_trans_handle *trans;
2351 struct btrfs_root *root = BTRFS_I(dir)->root;
2352 struct inode *inode = NULL;
2353 int err;
2354 int drop_inode = 0;
2355 u64 objectid;
2356 unsigned long nr = 0;
2357
2358 if (!new_valid_dev(rdev))
2359 return -EINVAL;
2360
2361 err = btrfs_check_free_space(root, 1, 0);
2362 if (err)
2363 goto fail;
2364
2365 trans = btrfs_start_transaction(root, 1);
2366 btrfs_set_trans_block_group(trans, dir);
2367
2368 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2369 if (err) {
2370 err = -ENOSPC;
2371 goto out_unlock;
2372 }
2373
2374 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
2375 dentry->d_name.len,
2376 dentry->d_parent->d_inode->i_ino, objectid,
2377 BTRFS_I(dir)->block_group, mode);
2378 err = PTR_ERR(inode);
2379 if (IS_ERR(inode))
2380 goto out_unlock;
2381
2382 err = btrfs_init_acl(inode, dir);
2383 if (err) {
2384 drop_inode = 1;
2385 goto out_unlock;
2386 }
2387
2388 btrfs_set_trans_block_group(trans, inode);
2389 err = btrfs_add_nondir(trans, dentry, inode, 0);
2390 if (err)
2391 drop_inode = 1;
2392 else {
2393 inode->i_op = &btrfs_special_inode_operations;
2394 init_special_inode(inode, inode->i_mode, rdev);
2395 btrfs_update_inode(trans, root, inode);
2396 }
2397 dir->i_sb->s_dirt = 1;
2398 btrfs_update_inode_block_group(trans, inode);
2399 btrfs_update_inode_block_group(trans, dir);
2400 out_unlock:
2401 nr = trans->blocks_used;
2402 btrfs_end_transaction_throttle(trans, root);
2403 fail:
2404 if (drop_inode) {
2405 inode_dec_link_count(inode);
2406 iput(inode);
2407 }
2408 btrfs_btree_balance_dirty(root, nr);
2409 return err;
2410 }
2411
2412 static int btrfs_create(struct inode *dir, struct dentry *dentry,
2413 int mode, struct nameidata *nd)
2414 {
2415 struct btrfs_trans_handle *trans;
2416 struct btrfs_root *root = BTRFS_I(dir)->root;
2417 struct inode *inode = NULL;
2418 int err;
2419 int drop_inode = 0;
2420 unsigned long nr = 0;
2421 u64 objectid;
2422
2423 err = btrfs_check_free_space(root, 1, 0);
2424 if (err)
2425 goto fail;
2426 trans = btrfs_start_transaction(root, 1);
2427 btrfs_set_trans_block_group(trans, dir);
2428
2429 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2430 if (err) {
2431 err = -ENOSPC;
2432 goto out_unlock;
2433 }
2434
2435 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
2436 dentry->d_name.len,
2437 dentry->d_parent->d_inode->i_ino,
2438 objectid, BTRFS_I(dir)->block_group, mode);
2439 err = PTR_ERR(inode);
2440 if (IS_ERR(inode))
2441 goto out_unlock;
2442
2443 err = btrfs_init_acl(inode, dir);
2444 if (err) {
2445 drop_inode = 1;
2446 goto out_unlock;
2447 }
2448
2449 btrfs_set_trans_block_group(trans, inode);
2450 err = btrfs_add_nondir(trans, dentry, inode, 0);
2451 if (err)
2452 drop_inode = 1;
2453 else {
2454 inode->i_mapping->a_ops = &btrfs_aops;
2455 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2456 inode->i_fop = &btrfs_file_operations;
2457 inode->i_op = &btrfs_file_inode_operations;
2458 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
2459 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
2460 inode->i_mapping, GFP_NOFS);
2461 extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
2462 inode->i_mapping, GFP_NOFS);
2463 INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
2464 mutex_init(&BTRFS_I(inode)->csum_mutex);
2465 mutex_init(&BTRFS_I(inode)->extent_mutex);
2466 BTRFS_I(inode)->delalloc_bytes = 0;
2467 BTRFS_I(inode)->disk_i_size = 0;
2468 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
2469 btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
2470 }
2471 dir->i_sb->s_dirt = 1;
2472 btrfs_update_inode_block_group(trans, inode);
2473 btrfs_update_inode_block_group(trans, dir);
2474 out_unlock:
2475 nr = trans->blocks_used;
2476 btrfs_end_transaction_throttle(trans, root);
2477 fail:
2478 if (drop_inode) {
2479 inode_dec_link_count(inode);
2480 iput(inode);
2481 }
2482 btrfs_btree_balance_dirty(root, nr);
2483 return err;
2484 }
2485
2486 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
2487 struct dentry *dentry)
2488 {
2489 struct btrfs_trans_handle *trans;
2490 struct btrfs_root *root = BTRFS_I(dir)->root;
2491 struct inode *inode = old_dentry->d_inode;
2492 unsigned long nr = 0;
2493 int err;
2494 int drop_inode = 0;
2495
2496 if (inode->i_nlink == 0)
2497 return -ENOENT;
2498
2499 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
2500 inode->i_nlink++;
2501 #else
2502 inc_nlink(inode);
2503 #endif
2504 err = btrfs_check_free_space(root, 1, 0);
2505 if (err)
2506 goto fail;
2507 err = btrfs_set_inode_index(dir, inode);
2508 if (err)
2509 goto fail;
2510
2511 trans = btrfs_start_transaction(root, 1);
2512
2513 btrfs_set_trans_block_group(trans, dir);
2514 atomic_inc(&inode->i_count);
2515
2516 err = btrfs_add_nondir(trans, dentry, inode, 1);
2517
2518 if (err)
2519 drop_inode = 1;
2520
2521 dir->i_sb->s_dirt = 1;
2522 btrfs_update_inode_block_group(trans, dir);
2523 err = btrfs_update_inode(trans, root, inode);
2524
2525 if (err)
2526 drop_inode = 1;
2527
2528 nr = trans->blocks_used;
2529 btrfs_end_transaction_throttle(trans, root);
2530 fail:
2531 if (drop_inode) {
2532 inode_dec_link_count(inode);
2533 iput(inode);
2534 }
2535 btrfs_btree_balance_dirty(root, nr);
2536 return err;
2537 }
2538
2539 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
2540 {
2541 struct inode *inode = NULL;
2542 struct btrfs_trans_handle *trans;
2543 struct btrfs_root *root = BTRFS_I(dir)->root;
2544 int err = 0;
2545 int drop_on_err = 0;
2546 u64 objectid = 0;
2547 unsigned long nr = 1;
2548
2549 err = btrfs_check_free_space(root, 1, 0);
2550 if (err)
2551 goto out_unlock;
2552
2553 trans = btrfs_start_transaction(root, 1);
2554 btrfs_set_trans_block_group(trans, dir);
2555
2556 if (IS_ERR(trans)) {
2557 err = PTR_ERR(trans);
2558 goto out_unlock;
2559 }
2560
2561 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2562 if (err) {
2563 err = -ENOSPC;
2564 goto out_unlock;
2565 }
2566
2567 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
2568 dentry->d_name.len,
2569 dentry->d_parent->d_inode->i_ino, objectid,
2570 BTRFS_I(dir)->block_group, S_IFDIR | mode);
2571 if (IS_ERR(inode)) {
2572 err = PTR_ERR(inode);
2573 goto out_fail;
2574 }
2575
2576 drop_on_err = 1;
2577
2578 err = btrfs_init_acl(inode, dir);
2579 if (err)
2580 goto out_fail;
2581
2582 inode->i_op = &btrfs_dir_inode_operations;
2583 inode->i_fop = &btrfs_dir_file_operations;
2584 btrfs_set_trans_block_group(trans, inode);
2585
2586 btrfs_i_size_write(inode, 0);
2587 err = btrfs_update_inode(trans, root, inode);
2588 if (err)
2589 goto out_fail;
2590
2591 err = btrfs_add_link(trans, dentry, inode, 0);
2592 if (err)
2593 goto out_fail;
2594
2595 d_instantiate(dentry, inode);
2596 drop_on_err = 0;
2597 dir->i_sb->s_dirt = 1;
2598 btrfs_update_inode_block_group(trans, inode);
2599 btrfs_update_inode_block_group(trans, dir);
2600
2601 out_fail:
2602 nr = trans->blocks_used;
2603 btrfs_end_transaction_throttle(trans, root);
2604
2605 out_unlock:
2606 if (drop_on_err)
2607 iput(inode);
2608 btrfs_btree_balance_dirty(root, nr);
2609 return err;
2610 }
2611
2612 static int merge_extent_mapping(struct extent_map_tree *em_tree,
2613 struct extent_map *existing,
2614 struct extent_map *em,
2615 u64 map_start, u64 map_len)
2616 {
2617 u64 start_diff;
2618
2619 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
2620 start_diff = map_start - em->start;
2621 em->start = map_start;
2622 em->len = map_len;
2623 if (em->block_start < EXTENT_MAP_LAST_BYTE)
2624 em->block_start += start_diff;
2625 return add_extent_mapping(em_tree, em);
2626 }
2627
2628 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
2629 size_t pg_offset, u64 start, u64 len,
2630 int create)
2631 {
2632 int ret;
2633 int err = 0;
2634 u64 bytenr;
2635 u64 extent_start = 0;
2636 u64 extent_end = 0;
2637 u64 objectid = inode->i_ino;
2638 u32 found_type;
2639 struct btrfs_path *path = NULL;
2640 struct btrfs_root *root = BTRFS_I(inode)->root;
2641 struct btrfs_file_extent_item *item;
2642 struct extent_buffer *leaf;
2643 struct btrfs_key found_key;
2644 struct extent_map *em = NULL;
2645 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
2646 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2647 struct btrfs_trans_handle *trans = NULL;
2648
2649 again:
2650 spin_lock(&em_tree->lock);
2651 em = lookup_extent_mapping(em_tree, start, len);
2652 if (em)
2653 em->bdev = root->fs_info->fs_devices->latest_bdev;
2654 spin_unlock(&em_tree->lock);
2655
2656 if (em) {
2657 if (em->start > start || em->start + em->len <= start)
2658 free_extent_map(em);
2659 else if (em->block_start == EXTENT_MAP_INLINE && page)
2660 free_extent_map(em);
2661 else
2662 goto out;
2663 }
2664 em = alloc_extent_map(GFP_NOFS);
2665 if (!em) {
2666 err = -ENOMEM;
2667 goto out;
2668 }
2669 em->bdev = root->fs_info->fs_devices->latest_bdev;
2670 em->start = EXTENT_MAP_HOLE;
2671 em->len = (u64)-1;
2672
2673 if (!path) {
2674 path = btrfs_alloc_path();
2675 BUG_ON(!path);
2676 }
2677
2678 ret = btrfs_lookup_file_extent(trans, root, path,
2679 objectid, start, trans != NULL);
2680 if (ret < 0) {
2681 err = ret;
2682 goto out;
2683 }
2684
2685 if (ret != 0) {
2686 if (path->slots[0] == 0)
2687 goto not_found;
2688 path->slots[0]--;
2689 }
2690
2691 leaf = path->nodes[0];
2692 item = btrfs_item_ptr(leaf, path->slots[0],
2693 struct btrfs_file_extent_item);
2694 /* are we inside the extent that was found? */
2695 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2696 found_type = btrfs_key_type(&found_key);
2697 if (found_key.objectid != objectid ||
2698 found_type != BTRFS_EXTENT_DATA_KEY) {
2699 goto not_found;
2700 }
2701
2702 found_type = btrfs_file_extent_type(leaf, item);
2703 extent_start = found_key.offset;
2704 if (found_type == BTRFS_FILE_EXTENT_REG) {
2705 extent_end = extent_start +
2706 btrfs_file_extent_num_bytes(leaf, item);
2707 err = 0;
2708 if (start < extent_start || start >= extent_end) {
2709 em->start = start;
2710 if (start < extent_start) {
2711 if (start + len <= extent_start)
2712 goto not_found;
2713 em->len = extent_end - extent_start;
2714 } else {
2715 em->len = len;
2716 }
2717 goto not_found_em;
2718 }
2719 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
2720 if (bytenr == 0) {
2721 em->start = extent_start;
2722 em->len = extent_end - extent_start;
2723 em->block_start = EXTENT_MAP_HOLE;
2724 goto insert;
2725 }
2726 bytenr += btrfs_file_extent_offset(leaf, item);
2727 em->block_start = bytenr;
2728 em->start = extent_start;
2729 em->len = extent_end - extent_start;
2730 goto insert;
2731 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
2732 u64 page_start;
2733 unsigned long ptr;
2734 char *map;
2735 size_t size;
2736 size_t extent_offset;
2737 size_t copy_size;
2738
2739 size = btrfs_file_extent_inline_len(leaf, btrfs_item_nr(leaf,
2740 path->slots[0]));
2741 extent_end = (extent_start + size + root->sectorsize - 1) &
2742 ~((u64)root->sectorsize - 1);
2743 if (start < extent_start || start >= extent_end) {
2744 em->start = start;
2745 if (start < extent_start) {
2746 if (start + len <= extent_start)
2747 goto not_found;
2748 em->len = extent_end - extent_start;
2749 } else {
2750 em->len = len;
2751 }
2752 goto not_found_em;
2753 }
2754 em->block_start = EXTENT_MAP_INLINE;
2755
2756 if (!page) {
2757 em->start = extent_start;
2758 em->len = size;
2759 goto out;
2760 }
2761
2762 page_start = page_offset(page) + pg_offset;
2763 extent_offset = page_start - extent_start;
2764 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
2765 size - extent_offset);
2766 em->start = extent_start + extent_offset;
2767 em->len = (copy_size + root->sectorsize - 1) &
2768 ~((u64)root->sectorsize - 1);
2769 map = kmap(page);
2770 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
2771 if (create == 0 && !PageUptodate(page)) {
2772 read_extent_buffer(leaf, map + pg_offset, ptr,
2773 copy_size);
2774 flush_dcache_page(page);
2775 } else if (create && PageUptodate(page)) {
2776 if (!trans) {
2777 kunmap(page);
2778 free_extent_map(em);
2779 em = NULL;
2780 btrfs_release_path(root, path);
2781 trans = btrfs_join_transaction(root, 1);
2782 goto again;
2783 }
2784 write_extent_buffer(leaf, map + pg_offset, ptr,
2785 copy_size);
2786 btrfs_mark_buffer_dirty(leaf);
2787 }
2788 kunmap(page);
2789 set_extent_uptodate(io_tree, em->start,
2790 extent_map_end(em) - 1, GFP_NOFS);
2791 goto insert;
2792 } else {
2793 printk("unkknown found_type %d\n", found_type);
2794 WARN_ON(1);
2795 }
2796 not_found:
2797 em->start = start;
2798 em->len = len;
2799 not_found_em:
2800 em->block_start = EXTENT_MAP_HOLE;
2801 insert:
2802 btrfs_release_path(root, path);
2803 if (em->start > start || extent_map_end(em) <= start) {
2804 printk("bad extent! em: [%Lu %Lu] passed [%Lu %Lu]\n", em->start, em->len, start, len);
2805 err = -EIO;
2806 goto out;
2807 }
2808
2809 err = 0;
2810 spin_lock(&em_tree->lock);
2811 ret = add_extent_mapping(em_tree, em);
2812 /* it is possible that someone inserted the extent into the tree
2813 * while we had the lock dropped. It is also possible that
2814 * an overlapping map exists in the tree
2815 */
2816 if (ret == -EEXIST) {
2817 struct extent_map *existing;
2818
2819 ret = 0;
2820
2821 existing = lookup_extent_mapping(em_tree, start, len);
2822 if (existing && (existing->start > start ||
2823 existing->start + existing->len <= start)) {
2824 free_extent_map(existing);
2825 existing = NULL;
2826 }
2827 if (!existing) {
2828 existing = lookup_extent_mapping(em_tree, em->start,
2829 em->len);
2830 if (existing) {
2831 err = merge_extent_mapping(em_tree, existing,
2832 em, start,
2833 root->sectorsize);
2834 free_extent_map(existing);
2835 if (err) {
2836 free_extent_map(em);
2837 em = NULL;
2838 }
2839 } else {
2840 err = -EIO;
2841 printk("failing to insert %Lu %Lu\n",
2842 start, len);
2843 free_extent_map(em);
2844 em = NULL;
2845 }
2846 } else {
2847 free_extent_map(em);
2848 em = existing;
2849 err = 0;
2850 }
2851 }
2852 spin_unlock(&em_tree->lock);
2853 out:
2854 if (path)
2855 btrfs_free_path(path);
2856 if (trans) {
2857 ret = btrfs_end_transaction(trans, root);
2858 if (!err) {
2859 err = ret;
2860 }
2861 }
2862 if (err) {
2863 free_extent_map(em);
2864 WARN_ON(1);
2865 return ERR_PTR(err);
2866 }
2867 return em;
2868 }
2869
2870 #if 0 /* waiting for O_DIRECT reads */
2871 static int btrfs_get_block(struct inode *inode, sector_t iblock,
2872 struct buffer_head *bh_result, int create)
2873 {
2874 struct extent_map *em;
2875 u64 start = (u64)iblock << inode->i_blkbits;
2876 struct btrfs_multi_bio *multi = NULL;
2877 struct btrfs_root *root = BTRFS_I(inode)->root;
2878 u64 len;
2879 u64 logical;
2880 u64 map_length;
2881 int ret = 0;
2882
2883 em = btrfs_get_extent(inode, NULL, 0, start, bh_result->b_size, 0);
2884
2885 if (!em || IS_ERR(em))
2886 goto out;
2887
2888 if (em->start > start || em->start + em->len <= start) {
2889 goto out;
2890 }
2891
2892 if (em->block_start == EXTENT_MAP_INLINE) {
2893 ret = -EINVAL;
2894 goto out;
2895 }
2896
2897 len = em->start + em->len - start;
2898 len = min_t(u64, len, INT_LIMIT(typeof(bh_result->b_size)));
2899
2900 if (em->block_start == EXTENT_MAP_HOLE ||
2901 em->block_start == EXTENT_MAP_DELALLOC) {
2902 bh_result->b_size = len;
2903 goto out;
2904 }
2905
2906 logical = start - em->start;
2907 logical = em->block_start + logical;
2908
2909 map_length = len;
2910 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
2911 logical, &map_length, &multi, 0);
2912 BUG_ON(ret);
2913 bh_result->b_blocknr = multi->stripes[0].physical >> inode->i_blkbits;
2914 bh_result->b_size = min(map_length, len);
2915
2916 bh_result->b_bdev = multi->stripes[0].dev->bdev;
2917 set_buffer_mapped(bh_result);
2918 kfree(multi);
2919 out:
2920 free_extent_map(em);
2921 return ret;
2922 }
2923 #endif
2924
2925 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
2926 const struct iovec *iov, loff_t offset,
2927 unsigned long nr_segs)
2928 {
2929 return -EINVAL;
2930 #if 0
2931 struct file *file = iocb->ki_filp;
2932 struct inode *inode = file->f_mapping->host;
2933
2934 if (rw == WRITE)
2935 return -EINVAL;
2936
2937 return blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
2938 offset, nr_segs, btrfs_get_block, NULL);
2939 #endif
2940 }
2941
2942 static sector_t btrfs_bmap(struct address_space *mapping, sector_t iblock)
2943 {
2944 return extent_bmap(mapping, iblock, btrfs_get_extent);
2945 }
2946
2947 int btrfs_readpage(struct file *file, struct page *page)
2948 {
2949 struct extent_io_tree *tree;
2950 tree = &BTRFS_I(page->mapping->host)->io_tree;
2951 return extent_read_full_page(tree, page, btrfs_get_extent);
2952 }
2953
2954 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
2955 {
2956 struct extent_io_tree *tree;
2957
2958
2959 if (current->flags & PF_MEMALLOC) {
2960 redirty_page_for_writepage(wbc, page);
2961 unlock_page(page);
2962 return 0;
2963 }
2964 tree = &BTRFS_I(page->mapping->host)->io_tree;
2965 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
2966 }
2967
2968 int btrfs_writepages(struct address_space *mapping,
2969 struct writeback_control *wbc)
2970 {
2971 struct extent_io_tree *tree;
2972 tree = &BTRFS_I(mapping->host)->io_tree;
2973 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
2974 }
2975
2976 static int
2977 btrfs_readpages(struct file *file, struct address_space *mapping,
2978 struct list_head *pages, unsigned nr_pages)
2979 {
2980 struct extent_io_tree *tree;
2981 tree = &BTRFS_I(mapping->host)->io_tree;
2982 return extent_readpages(tree, mapping, pages, nr_pages,
2983 btrfs_get_extent);
2984 }
2985 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
2986 {
2987 struct extent_io_tree *tree;
2988 struct extent_map_tree *map;
2989 int ret;
2990
2991 tree = &BTRFS_I(page->mapping->host)->io_tree;
2992 map = &BTRFS_I(page->mapping->host)->extent_tree;
2993 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
2994 if (ret == 1) {
2995 ClearPagePrivate(page);
2996 set_page_private(page, 0);
2997 page_cache_release(page);
2998 }
2999 return ret;
3000 }
3001
3002 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
3003 {
3004 return __btrfs_releasepage(page, gfp_flags);
3005 }
3006
3007 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
3008 {
3009 struct extent_io_tree *tree;
3010 struct btrfs_ordered_extent *ordered;
3011 u64 page_start = page_offset(page);
3012 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
3013
3014 wait_on_page_writeback(page);
3015 tree = &BTRFS_I(page->mapping->host)->io_tree;
3016 if (offset) {
3017 btrfs_releasepage(page, GFP_NOFS);
3018 return;
3019 }
3020
3021 lock_extent(tree, page_start, page_end, GFP_NOFS);
3022 ordered = btrfs_lookup_ordered_extent(page->mapping->host,
3023 page_offset(page));
3024 if (ordered) {
3025 /*
3026 * IO on this page will never be started, so we need
3027 * to account for any ordered extents now
3028 */
3029 clear_extent_bit(tree, page_start, page_end,
3030 EXTENT_DIRTY | EXTENT_DELALLOC |
3031 EXTENT_LOCKED, 1, 0, GFP_NOFS);
3032 btrfs_finish_ordered_io(page->mapping->host,
3033 page_start, page_end);
3034 btrfs_put_ordered_extent(ordered);
3035 lock_extent(tree, page_start, page_end, GFP_NOFS);
3036 }
3037 clear_extent_bit(tree, page_start, page_end,
3038 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
3039 EXTENT_ORDERED,
3040 1, 1, GFP_NOFS);
3041 __btrfs_releasepage(page, GFP_NOFS);
3042
3043 ClearPageChecked(page);
3044 if (PagePrivate(page)) {
3045 ClearPagePrivate(page);
3046 set_page_private(page, 0);
3047 page_cache_release(page);
3048 }
3049 }
3050
3051 /*
3052 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
3053 * called from a page fault handler when a page is first dirtied. Hence we must
3054 * be careful to check for EOF conditions here. We set the page up correctly
3055 * for a written page which means we get ENOSPC checking when writing into
3056 * holes and correct delalloc and unwritten extent mapping on filesystems that
3057 * support these features.
3058 *
3059 * We are not allowed to take the i_mutex here so we have to play games to
3060 * protect against truncate races as the page could now be beyond EOF. Because
3061 * vmtruncate() writes the inode size before removing pages, once we have the
3062 * page lock we can determine safely if the page is beyond EOF. If it is not
3063 * beyond EOF, then the page is guaranteed safe against truncation until we
3064 * unlock the page.
3065 */
3066 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
3067 {
3068 struct inode *inode = fdentry(vma->vm_file)->d_inode;
3069 struct btrfs_root *root = BTRFS_I(inode)->root;
3070 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3071 struct btrfs_ordered_extent *ordered;
3072 char *kaddr;
3073 unsigned long zero_start;
3074 loff_t size;
3075 int ret;
3076 u64 page_start;
3077 u64 page_end;
3078
3079 ret = btrfs_check_free_space(root, PAGE_CACHE_SIZE, 0);
3080 if (ret)
3081 goto out;
3082
3083 ret = -EINVAL;
3084 again:
3085 lock_page(page);
3086 size = i_size_read(inode);
3087 page_start = page_offset(page);
3088 page_end = page_start + PAGE_CACHE_SIZE - 1;
3089
3090 if ((page->mapping != inode->i_mapping) ||
3091 (page_start >= size)) {
3092 /* page got truncated out from underneath us */
3093 goto out_unlock;
3094 }
3095 wait_on_page_writeback(page);
3096
3097 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
3098 set_page_extent_mapped(page);
3099
3100 /*
3101 * we can't set the delalloc bits if there are pending ordered
3102 * extents. Drop our locks and wait for them to finish
3103 */
3104 ordered = btrfs_lookup_ordered_extent(inode, page_start);
3105 if (ordered) {
3106 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
3107 unlock_page(page);
3108 btrfs_start_ordered_extent(inode, ordered, 1);
3109 btrfs_put_ordered_extent(ordered);
3110 goto again;
3111 }
3112
3113 btrfs_set_extent_delalloc(inode, page_start, page_end);
3114 ret = 0;
3115
3116 /* page is wholly or partially inside EOF */
3117 if (page_start + PAGE_CACHE_SIZE > size)
3118 zero_start = size & ~PAGE_CACHE_MASK;
3119 else
3120 zero_start = PAGE_CACHE_SIZE;
3121
3122 if (zero_start != PAGE_CACHE_SIZE) {
3123 kaddr = kmap(page);
3124 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
3125 flush_dcache_page(page);
3126 kunmap(page);
3127 }
3128 ClearPageChecked(page);
3129 set_page_dirty(page);
3130 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
3131
3132 out_unlock:
3133 unlock_page(page);
3134 out:
3135 return ret;
3136 }
3137
3138 static void btrfs_truncate(struct inode *inode)
3139 {
3140 struct btrfs_root *root = BTRFS_I(inode)->root;
3141 int ret;
3142 struct btrfs_trans_handle *trans;
3143 unsigned long nr;
3144 u64 mask = root->sectorsize - 1;
3145
3146 if (!S_ISREG(inode->i_mode))
3147 return;
3148 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
3149 return;
3150
3151 btrfs_truncate_page(inode->i_mapping, inode->i_size);
3152 btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
3153
3154 trans = btrfs_start_transaction(root, 1);
3155 btrfs_set_trans_block_group(trans, inode);
3156 btrfs_i_size_write(inode, inode->i_size);
3157
3158 ret = btrfs_orphan_add(trans, inode);
3159 if (ret)
3160 goto out;
3161 /* FIXME, add redo link to tree so we don't leak on crash */
3162 ret = btrfs_truncate_in_trans(trans, root, inode,
3163 BTRFS_EXTENT_DATA_KEY);
3164 btrfs_update_inode(trans, root, inode);
3165
3166 ret = btrfs_orphan_del(trans, inode);
3167 BUG_ON(ret);
3168
3169 out:
3170 nr = trans->blocks_used;
3171 ret = btrfs_end_transaction_throttle(trans, root);
3172 BUG_ON(ret);
3173 btrfs_btree_balance_dirty(root, nr);
3174 }
3175
3176 /*
3177 * Invalidate a single dcache entry at the root of the filesystem.
3178 * Needed after creation of snapshot or subvolume.
3179 */
3180 void btrfs_invalidate_dcache_root(struct btrfs_root *root, char *name,
3181 int namelen)
3182 {
3183 struct dentry *alias, *entry;
3184 struct qstr qstr;
3185
3186 alias = d_find_alias(root->fs_info->sb->s_root->d_inode);
3187 if (alias) {
3188 qstr.name = name;
3189 qstr.len = namelen;
3190 /* change me if btrfs ever gets a d_hash operation */
3191 qstr.hash = full_name_hash(qstr.name, qstr.len);
3192 entry = d_lookup(alias, &qstr);
3193 dput(alias);
3194 if (entry) {
3195 d_invalidate(entry);
3196 dput(entry);
3197 }
3198 }
3199 }
3200
3201 int btrfs_create_subvol_root(struct btrfs_root *new_root,
3202 struct btrfs_trans_handle *trans, u64 new_dirid,
3203 struct btrfs_block_group_cache *block_group)
3204 {
3205 struct inode *inode;
3206
3207 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid,
3208 new_dirid, block_group, S_IFDIR | 0700);
3209 if (IS_ERR(inode))
3210 return PTR_ERR(inode);
3211 inode->i_op = &btrfs_dir_inode_operations;
3212 inode->i_fop = &btrfs_dir_file_operations;
3213 new_root->inode = inode;
3214
3215 inode->i_nlink = 1;
3216 btrfs_i_size_write(inode, 0);
3217
3218 return btrfs_update_inode(trans, new_root, inode);
3219 }
3220
3221 unsigned long btrfs_force_ra(struct address_space *mapping,
3222 struct file_ra_state *ra, struct file *file,
3223 pgoff_t offset, pgoff_t last_index)
3224 {
3225 pgoff_t req_size = last_index - offset + 1;
3226
3227 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
3228 offset = page_cache_readahead(mapping, ra, file, offset, req_size);
3229 return offset;
3230 #else
3231 page_cache_sync_readahead(mapping, ra, file, offset, req_size);
3232 return offset + req_size;
3233 #endif
3234 }
3235
3236 struct inode *btrfs_alloc_inode(struct super_block *sb)
3237 {
3238 struct btrfs_inode *ei;
3239
3240 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
3241 if (!ei)
3242 return NULL;
3243 ei->last_trans = 0;
3244 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
3245 ei->i_acl = BTRFS_ACL_NOT_CACHED;
3246 ei->i_default_acl = BTRFS_ACL_NOT_CACHED;
3247 INIT_LIST_HEAD(&ei->i_orphan);
3248 return &ei->vfs_inode;
3249 }
3250
3251 void btrfs_destroy_inode(struct inode *inode)
3252 {
3253 struct btrfs_ordered_extent *ordered;
3254 WARN_ON(!list_empty(&inode->i_dentry));
3255 WARN_ON(inode->i_data.nrpages);
3256
3257 if (BTRFS_I(inode)->i_acl &&
3258 BTRFS_I(inode)->i_acl != BTRFS_ACL_NOT_CACHED)
3259 posix_acl_release(BTRFS_I(inode)->i_acl);
3260 if (BTRFS_I(inode)->i_default_acl &&
3261 BTRFS_I(inode)->i_default_acl != BTRFS_ACL_NOT_CACHED)
3262 posix_acl_release(BTRFS_I(inode)->i_default_acl);
3263
3264 spin_lock(&BTRFS_I(inode)->root->list_lock);
3265 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
3266 printk(KERN_ERR "BTRFS: inode %lu: inode still on the orphan"
3267 " list\n", inode->i_ino);
3268 dump_stack();
3269 }
3270 spin_unlock(&BTRFS_I(inode)->root->list_lock);
3271
3272 while(1) {
3273 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
3274 if (!ordered)
3275 break;
3276 else {
3277 printk("found ordered extent %Lu %Lu\n",
3278 ordered->file_offset, ordered->len);
3279 btrfs_remove_ordered_extent(inode, ordered);
3280 btrfs_put_ordered_extent(ordered);
3281 btrfs_put_ordered_extent(ordered);
3282 }
3283 }
3284 btrfs_drop_extent_cache(inode, 0, (u64)-1);
3285 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
3286 }
3287
3288 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
3289 static void init_once(void *foo)
3290 #elif LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
3291 static void init_once(struct kmem_cache * cachep, void *foo)
3292 #else
3293 static void init_once(void * foo, struct kmem_cache * cachep,
3294 unsigned long flags)
3295 #endif
3296 {
3297 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
3298
3299 inode_init_once(&ei->vfs_inode);
3300 }
3301
3302 void btrfs_destroy_cachep(void)
3303 {
3304 if (btrfs_inode_cachep)
3305 kmem_cache_destroy(btrfs_inode_cachep);
3306 if (btrfs_trans_handle_cachep)
3307 kmem_cache_destroy(btrfs_trans_handle_cachep);
3308 if (btrfs_transaction_cachep)
3309 kmem_cache_destroy(btrfs_transaction_cachep);
3310 if (btrfs_bit_radix_cachep)
3311 kmem_cache_destroy(btrfs_bit_radix_cachep);
3312 if (btrfs_path_cachep)
3313 kmem_cache_destroy(btrfs_path_cachep);
3314 }
3315
3316 struct kmem_cache *btrfs_cache_create(const char *name, size_t size,
3317 unsigned long extra_flags,
3318 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
3319 void (*ctor)(void *)
3320 #elif LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
3321 void (*ctor)(struct kmem_cache *, void *)
3322 #else
3323 void (*ctor)(void *, struct kmem_cache *,
3324 unsigned long)
3325 #endif
3326 )
3327 {
3328 return kmem_cache_create(name, size, 0, (SLAB_RECLAIM_ACCOUNT |
3329 SLAB_MEM_SPREAD | extra_flags), ctor
3330 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
3331 ,NULL
3332 #endif
3333 );
3334 }
3335
3336 int btrfs_init_cachep(void)
3337 {
3338 btrfs_inode_cachep = btrfs_cache_create("btrfs_inode_cache",
3339 sizeof(struct btrfs_inode),
3340 0, init_once);
3341 if (!btrfs_inode_cachep)
3342 goto fail;
3343 btrfs_trans_handle_cachep =
3344 btrfs_cache_create("btrfs_trans_handle_cache",
3345 sizeof(struct btrfs_trans_handle),
3346 0, NULL);
3347 if (!btrfs_trans_handle_cachep)
3348 goto fail;
3349 btrfs_transaction_cachep = btrfs_cache_create("btrfs_transaction_cache",
3350 sizeof(struct btrfs_transaction),
3351 0, NULL);
3352 if (!btrfs_transaction_cachep)
3353 goto fail;
3354 btrfs_path_cachep = btrfs_cache_create("btrfs_path_cache",
3355 sizeof(struct btrfs_path),
3356 0, NULL);
3357 if (!btrfs_path_cachep)
3358 goto fail;
3359 btrfs_bit_radix_cachep = btrfs_cache_create("btrfs_radix", 256,
3360 SLAB_DESTROY_BY_RCU, NULL);
3361 if (!btrfs_bit_radix_cachep)
3362 goto fail;
3363 return 0;
3364 fail:
3365 btrfs_destroy_cachep();
3366 return -ENOMEM;
3367 }
3368
3369 static int btrfs_getattr(struct vfsmount *mnt,
3370 struct dentry *dentry, struct kstat *stat)
3371 {
3372 struct inode *inode = dentry->d_inode;
3373 generic_fillattr(inode, stat);
3374 stat->blksize = PAGE_CACHE_SIZE;
3375 stat->blocks = inode->i_blocks + (BTRFS_I(inode)->delalloc_bytes >> 9);
3376 return 0;
3377 }
3378
3379 static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
3380 struct inode * new_dir,struct dentry *new_dentry)
3381 {
3382 struct btrfs_trans_handle *trans;
3383 struct btrfs_root *root = BTRFS_I(old_dir)->root;
3384 struct inode *new_inode = new_dentry->d_inode;
3385 struct inode *old_inode = old_dentry->d_inode;
3386 struct timespec ctime = CURRENT_TIME;
3387 int ret;
3388
3389 if (S_ISDIR(old_inode->i_mode) && new_inode &&
3390 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
3391 return -ENOTEMPTY;
3392 }
3393
3394 ret = btrfs_check_free_space(root, 1, 0);
3395 if (ret)
3396 goto out_unlock;
3397
3398 trans = btrfs_start_transaction(root, 1);
3399
3400 btrfs_set_trans_block_group(trans, new_dir);
3401
3402 old_dentry->d_inode->i_nlink++;
3403 old_dir->i_ctime = old_dir->i_mtime = ctime;
3404 new_dir->i_ctime = new_dir->i_mtime = ctime;
3405 old_inode->i_ctime = ctime;
3406
3407 ret = btrfs_unlink_trans(trans, root, old_dir, old_dentry);
3408 if (ret)
3409 goto out_fail;
3410
3411 if (new_inode) {
3412 new_inode->i_ctime = CURRENT_TIME;
3413 ret = btrfs_unlink_trans(trans, root, new_dir, new_dentry);
3414 if (ret)
3415 goto out_fail;
3416 if (new_inode->i_nlink == 0) {
3417 ret = btrfs_orphan_add(trans, new_inode);
3418 if (ret)
3419 goto out_fail;
3420 }
3421 }
3422 ret = btrfs_set_inode_index(new_dir, old_inode);
3423 if (ret)
3424 goto out_fail;
3425
3426 ret = btrfs_add_link(trans, new_dentry, old_inode, 1);
3427 if (ret)
3428 goto out_fail;
3429
3430 out_fail:
3431 btrfs_end_transaction_throttle(trans, root);
3432 out_unlock:
3433 return ret;
3434 }
3435
3436 int btrfs_start_delalloc_inodes(struct btrfs_root *root)
3437 {
3438 struct list_head *head = &root->fs_info->delalloc_inodes;
3439 struct btrfs_inode *binode;
3440 unsigned long flags;
3441
3442 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
3443 while(!list_empty(head)) {
3444 binode = list_entry(head->next, struct btrfs_inode,
3445 delalloc_inodes);
3446 atomic_inc(&binode->vfs_inode.i_count);
3447 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
3448 filemap_write_and_wait(binode->vfs_inode.i_mapping);
3449 iput(&binode->vfs_inode);
3450 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
3451 }
3452 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
3453 return 0;
3454 }
3455
3456 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
3457 const char *symname)
3458 {
3459 struct btrfs_trans_handle *trans;
3460 struct btrfs_root *root = BTRFS_I(dir)->root;
3461 struct btrfs_path *path;
3462 struct btrfs_key key;
3463 struct inode *inode = NULL;
3464 int err;
3465 int drop_inode = 0;
3466 u64 objectid;
3467 int name_len;
3468 int datasize;
3469 unsigned long ptr;
3470 struct btrfs_file_extent_item *ei;
3471 struct extent_buffer *leaf;
3472 unsigned long nr = 0;
3473
3474 name_len = strlen(symname) + 1;
3475 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
3476 return -ENAMETOOLONG;
3477
3478 err = btrfs_check_free_space(root, 1, 0);
3479 if (err)
3480 goto out_fail;
3481
3482 trans = btrfs_start_transaction(root, 1);
3483 btrfs_set_trans_block_group(trans, dir);
3484
3485 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
3486 if (err) {
3487 err = -ENOSPC;
3488 goto out_unlock;
3489 }
3490
3491 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
3492 dentry->d_name.len,
3493 dentry->d_parent->d_inode->i_ino, objectid,
3494 BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO);
3495 err = PTR_ERR(inode);
3496 if (IS_ERR(inode))
3497 goto out_unlock;
3498
3499 err = btrfs_init_acl(inode, dir);
3500 if (err) {
3501 drop_inode = 1;
3502 goto out_unlock;
3503 }
3504
3505 btrfs_set_trans_block_group(trans, inode);
3506 err = btrfs_add_nondir(trans, dentry, inode, 0);
3507 if (err)
3508 drop_inode = 1;
3509 else {
3510 inode->i_mapping->a_ops = &btrfs_aops;
3511 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3512 inode->i_fop = &btrfs_file_operations;
3513 inode->i_op = &btrfs_file_inode_operations;
3514 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
3515 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
3516 inode->i_mapping, GFP_NOFS);
3517 extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
3518 inode->i_mapping, GFP_NOFS);
3519 INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
3520 mutex_init(&BTRFS_I(inode)->csum_mutex);
3521 mutex_init(&BTRFS_I(inode)->extent_mutex);
3522 BTRFS_I(inode)->delalloc_bytes = 0;
3523 BTRFS_I(inode)->disk_i_size = 0;
3524 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
3525 btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
3526 }
3527 dir->i_sb->s_dirt = 1;
3528 btrfs_update_inode_block_group(trans, inode);
3529 btrfs_update_inode_block_group(trans, dir);
3530 if (drop_inode)
3531 goto out_unlock;
3532
3533 path = btrfs_alloc_path();
3534 BUG_ON(!path);
3535 key.objectid = inode->i_ino;
3536 key.offset = 0;
3537 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
3538 datasize = btrfs_file_extent_calc_inline_size(name_len);
3539 err = btrfs_insert_empty_item(trans, root, path, &key,
3540 datasize);
3541 if (err) {
3542 drop_inode = 1;
3543 goto out_unlock;
3544 }
3545 leaf = path->nodes[0];
3546 ei = btrfs_item_ptr(leaf, path->slots[0],
3547 struct btrfs_file_extent_item);
3548 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
3549 btrfs_set_file_extent_type(leaf, ei,
3550 BTRFS_FILE_EXTENT_INLINE);
3551 ptr = btrfs_file_extent_inline_start(ei);
3552 write_extent_buffer(leaf, symname, ptr, name_len);
3553 btrfs_mark_buffer_dirty(leaf);
3554 btrfs_free_path(path);
3555
3556 inode->i_op = &btrfs_symlink_inode_operations;
3557 inode->i_mapping->a_ops = &btrfs_symlink_aops;
3558 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3559 btrfs_i_size_write(inode, name_len - 1);
3560 err = btrfs_update_inode(trans, root, inode);
3561 if (err)
3562 drop_inode = 1;
3563
3564 out_unlock:
3565 nr = trans->blocks_used;
3566 btrfs_end_transaction_throttle(trans, root);
3567 out_fail:
3568 if (drop_inode) {
3569 inode_dec_link_count(inode);
3570 iput(inode);
3571 }
3572 btrfs_btree_balance_dirty(root, nr);
3573 return err;
3574 }
3575
3576 static int btrfs_set_page_dirty(struct page *page)
3577 {
3578 return __set_page_dirty_nobuffers(page);
3579 }
3580
3581 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
3582 static int btrfs_permission(struct inode *inode, int mask)
3583 #else
3584 static int btrfs_permission(struct inode *inode, int mask,
3585 struct nameidata *nd)
3586 #endif
3587 {
3588 if (btrfs_test_flag(inode, READONLY) && (mask & MAY_WRITE))
3589 return -EACCES;
3590 return generic_permission(inode, mask, btrfs_check_acl);
3591 }
3592
3593 static struct inode_operations btrfs_dir_inode_operations = {
3594 .lookup = btrfs_lookup,
3595 .create = btrfs_create,
3596 .unlink = btrfs_unlink,
3597 .link = btrfs_link,
3598 .mkdir = btrfs_mkdir,
3599 .rmdir = btrfs_rmdir,
3600 .rename = btrfs_rename,
3601 .symlink = btrfs_symlink,
3602 .setattr = btrfs_setattr,
3603 .mknod = btrfs_mknod,
3604 .setxattr = generic_setxattr,
3605 .getxattr = generic_getxattr,
3606 .listxattr = btrfs_listxattr,
3607 .removexattr = generic_removexattr,
3608 .permission = btrfs_permission,
3609 };
3610 static struct inode_operations btrfs_dir_ro_inode_operations = {
3611 .lookup = btrfs_lookup,
3612 .permission = btrfs_permission,
3613 };
3614 static struct file_operations btrfs_dir_file_operations = {
3615 .llseek = generic_file_llseek,
3616 .read = generic_read_dir,
3617 .readdir = btrfs_readdir,
3618 .unlocked_ioctl = btrfs_ioctl,
3619 #ifdef CONFIG_COMPAT
3620 .compat_ioctl = btrfs_ioctl,
3621 #endif
3622 .release = btrfs_release_file,
3623 };
3624
3625 static struct extent_io_ops btrfs_extent_io_ops = {
3626 .fill_delalloc = run_delalloc_range,
3627 .submit_bio_hook = btrfs_submit_bio_hook,
3628 .merge_bio_hook = btrfs_merge_bio_hook,
3629 .readpage_io_hook = btrfs_readpage_io_hook,
3630 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
3631 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
3632 .writepage_start_hook = btrfs_writepage_start_hook,
3633 .readpage_io_failed_hook = btrfs_io_failed_hook,
3634 .set_bit_hook = btrfs_set_bit_hook,
3635 .clear_bit_hook = btrfs_clear_bit_hook,
3636 };
3637
3638 static struct address_space_operations btrfs_aops = {
3639 .readpage = btrfs_readpage,
3640 .writepage = btrfs_writepage,
3641 .writepages = btrfs_writepages,
3642 .readpages = btrfs_readpages,
3643 .sync_page = block_sync_page,
3644 .bmap = btrfs_bmap,
3645 .direct_IO = btrfs_direct_IO,
3646 .invalidatepage = btrfs_invalidatepage,
3647 .releasepage = btrfs_releasepage,
3648 .set_page_dirty = btrfs_set_page_dirty,
3649 };
3650
3651 static struct address_space_operations btrfs_symlink_aops = {
3652 .readpage = btrfs_readpage,
3653 .writepage = btrfs_writepage,
3654 .invalidatepage = btrfs_invalidatepage,
3655 .releasepage = btrfs_releasepage,
3656 };
3657
3658 static struct inode_operations btrfs_file_inode_operations = {
3659 .truncate = btrfs_truncate,
3660 .getattr = btrfs_getattr,
3661 .setattr = btrfs_setattr,
3662 .setxattr = generic_setxattr,
3663 .getxattr = generic_getxattr,
3664 .listxattr = btrfs_listxattr,
3665 .removexattr = generic_removexattr,
3666 .permission = btrfs_permission,
3667 };
3668 static struct inode_operations btrfs_special_inode_operations = {
3669 .getattr = btrfs_getattr,
3670 .setattr = btrfs_setattr,
3671 .permission = btrfs_permission,
3672 .setxattr = generic_setxattr,
3673 .getxattr = generic_getxattr,
3674 .listxattr = btrfs_listxattr,
3675 .removexattr = generic_removexattr,
3676 };
3677 static struct inode_operations btrfs_symlink_inode_operations = {
3678 .readlink = generic_readlink,
3679 .follow_link = page_follow_link_light,
3680 .put_link = page_put_link,
3681 .permission = btrfs_permission,
3682 };
Linux kernel - Deliverables
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