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Btrfs: free space accounting redo
[mirror_ubuntu-bionic-kernel.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 #include "xattr.h"
49 #include "compat.h"
50 #include "tree-log.h"
51
52 struct btrfs_iget_args {
53 u64 ino;
54 struct btrfs_root *root;
55 };
56
57 static struct inode_operations btrfs_dir_inode_operations;
58 static struct inode_operations btrfs_symlink_inode_operations;
59 static struct inode_operations btrfs_dir_ro_inode_operations;
60 static struct inode_operations btrfs_special_inode_operations;
61 static struct inode_operations btrfs_file_inode_operations;
62 static struct address_space_operations btrfs_aops;
63 static struct address_space_operations btrfs_symlink_aops;
64 static struct file_operations btrfs_dir_file_operations;
65 static struct extent_io_ops btrfs_extent_io_ops;
66
67 static struct kmem_cache *btrfs_inode_cachep;
68 struct kmem_cache *btrfs_trans_handle_cachep;
69 struct kmem_cache *btrfs_transaction_cachep;
70 struct kmem_cache *btrfs_bit_radix_cachep;
71 struct kmem_cache *btrfs_path_cachep;
72
73 #define S_SHIFT 12
74 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
75 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
76 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
77 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
78 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
79 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
80 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
81 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
82 };
83
84 static void btrfs_truncate(struct inode *inode);
85
86 int btrfs_check_free_space(struct btrfs_root *root, u64 num_required,
87 int for_del)
88 {
89 u64 total;
90 u64 used;
91 u64 thresh;
92 unsigned long flags;
93 int ret = 0;
94
95 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
96 total = btrfs_super_total_bytes(&root->fs_info->super_copy);
97 used = btrfs_super_bytes_used(&root->fs_info->super_copy);
98 if (for_del)
99 thresh = total * 90;
100 else
101 thresh = total * 85;
102
103 do_div(thresh, 100);
104
105 if (used + root->fs_info->delalloc_bytes + num_required > thresh)
106 ret = -ENOSPC;
107 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
108 return ret;
109 }
110
111 static int cow_file_range(struct inode *inode, u64 start, u64 end)
112 {
113 struct btrfs_root *root = BTRFS_I(inode)->root;
114 struct btrfs_trans_handle *trans;
115 u64 alloc_hint = 0;
116 u64 num_bytes;
117 u64 cur_alloc_size;
118 u64 blocksize = root->sectorsize;
119 u64 orig_num_bytes;
120 struct btrfs_key ins;
121 struct extent_map *em;
122 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
123 int ret = 0;
124
125 trans = btrfs_join_transaction(root, 1);
126 BUG_ON(!trans);
127 btrfs_set_trans_block_group(trans, inode);
128
129 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
130 num_bytes = max(blocksize, num_bytes);
131 orig_num_bytes = num_bytes;
132
133 if (alloc_hint == EXTENT_MAP_INLINE)
134 goto out;
135
136 BUG_ON(num_bytes > btrfs_super_total_bytes(&root->fs_info->super_copy));
137 mutex_lock(&BTRFS_I(inode)->extent_mutex);
138 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1);
139 mutex_unlock(&BTRFS_I(inode)->extent_mutex);
140
141 while(num_bytes > 0) {
142 cur_alloc_size = min(num_bytes, root->fs_info->max_extent);
143 ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
144 root->sectorsize, 0, alloc_hint,
145 (u64)-1, &ins, 1);
146 if (ret) {
147 WARN_ON(1);
148 goto out;
149 }
150 em = alloc_extent_map(GFP_NOFS);
151 em->start = start;
152 em->len = ins.offset;
153 em->block_start = ins.objectid;
154 em->bdev = root->fs_info->fs_devices->latest_bdev;
155 mutex_lock(&BTRFS_I(inode)->extent_mutex);
156 set_bit(EXTENT_FLAG_PINNED, &em->flags);
157 while(1) {
158 spin_lock(&em_tree->lock);
159 ret = add_extent_mapping(em_tree, em);
160 spin_unlock(&em_tree->lock);
161 if (ret != -EEXIST) {
162 free_extent_map(em);
163 break;
164 }
165 btrfs_drop_extent_cache(inode, start,
166 start + ins.offset - 1);
167 }
168 mutex_unlock(&BTRFS_I(inode)->extent_mutex);
169
170 cur_alloc_size = ins.offset;
171 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
172 ins.offset, 0);
173 BUG_ON(ret);
174 if (num_bytes < cur_alloc_size) {
175 printk("num_bytes %Lu cur_alloc %Lu\n", num_bytes,
176 cur_alloc_size);
177 break;
178 }
179 num_bytes -= cur_alloc_size;
180 alloc_hint = ins.objectid + ins.offset;
181 start += cur_alloc_size;
182 }
183 out:
184 btrfs_end_transaction(trans, root);
185 return ret;
186 }
187
188 static int run_delalloc_nocow(struct inode *inode, u64 start, u64 end)
189 {
190 u64 extent_start;
191 u64 extent_end;
192 u64 bytenr;
193 u64 loops = 0;
194 u64 total_fs_bytes;
195 struct btrfs_root *root = BTRFS_I(inode)->root;
196 struct btrfs_block_group_cache *block_group;
197 struct btrfs_trans_handle *trans;
198 struct extent_buffer *leaf;
199 int found_type;
200 struct btrfs_path *path;
201 struct btrfs_file_extent_item *item;
202 int ret;
203 int err = 0;
204 struct btrfs_key found_key;
205
206 total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
207 path = btrfs_alloc_path();
208 BUG_ON(!path);
209 trans = btrfs_join_transaction(root, 1);
210 BUG_ON(!trans);
211 again:
212 ret = btrfs_lookup_file_extent(NULL, root, path,
213 inode->i_ino, start, 0);
214 if (ret < 0) {
215 err = ret;
216 goto out;
217 }
218
219 if (ret != 0) {
220 if (path->slots[0] == 0)
221 goto not_found;
222 path->slots[0]--;
223 }
224
225 leaf = path->nodes[0];
226 item = btrfs_item_ptr(leaf, path->slots[0],
227 struct btrfs_file_extent_item);
228
229 /* are we inside the extent that was found? */
230 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
231 found_type = btrfs_key_type(&found_key);
232 if (found_key.objectid != inode->i_ino ||
233 found_type != BTRFS_EXTENT_DATA_KEY)
234 goto not_found;
235
236 found_type = btrfs_file_extent_type(leaf, item);
237 extent_start = found_key.offset;
238 if (found_type == BTRFS_FILE_EXTENT_REG) {
239 u64 extent_num_bytes;
240
241 extent_num_bytes = btrfs_file_extent_num_bytes(leaf, item);
242 extent_end = extent_start + extent_num_bytes;
243 err = 0;
244
245 if (loops && start != extent_start)
246 goto not_found;
247
248 if (start < extent_start || start >= extent_end)
249 goto not_found;
250
251 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
252 if (bytenr == 0)
253 goto not_found;
254
255 if (btrfs_cross_ref_exists(trans, root, &found_key, bytenr))
256 goto not_found;
257 /*
258 * we may be called by the resizer, make sure we're inside
259 * the limits of the FS
260 */
261 block_group = btrfs_lookup_block_group(root->fs_info,
262 bytenr);
263 if (!block_group || block_group->ro)
264 goto not_found;
265
266 bytenr += btrfs_file_extent_offset(leaf, item);
267 extent_num_bytes = min(end + 1, extent_end) - start;
268 ret = btrfs_add_ordered_extent(inode, start, bytenr,
269 extent_num_bytes, 1);
270 if (ret) {
271 err = ret;
272 goto out;
273 }
274
275 btrfs_release_path(root, path);
276 start = extent_end;
277 if (start <= end) {
278 loops++;
279 goto again;
280 }
281 } else {
282 not_found:
283 btrfs_end_transaction(trans, root);
284 btrfs_free_path(path);
285 return cow_file_range(inode, start, end);
286 }
287 out:
288 WARN_ON(err);
289 btrfs_end_transaction(trans, root);
290 btrfs_free_path(path);
291 return err;
292 }
293
294 static int run_delalloc_range(struct inode *inode, u64 start, u64 end)
295 {
296 struct btrfs_root *root = BTRFS_I(inode)->root;
297 int ret;
298
299 if (btrfs_test_opt(root, NODATACOW) ||
300 btrfs_test_flag(inode, NODATACOW))
301 ret = run_delalloc_nocow(inode, start, end);
302 else
303 ret = cow_file_range(inode, start, end);
304
305 return ret;
306 }
307
308 int btrfs_set_bit_hook(struct inode *inode, u64 start, u64 end,
309 unsigned long old, unsigned long bits)
310 {
311 unsigned long flags;
312 if (!(old & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
313 struct btrfs_root *root = BTRFS_I(inode)->root;
314 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
315 BTRFS_I(inode)->delalloc_bytes += end - start + 1;
316 root->fs_info->delalloc_bytes += end - start + 1;
317 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
318 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
319 &root->fs_info->delalloc_inodes);
320 }
321 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
322 }
323 return 0;
324 }
325
326 int btrfs_clear_bit_hook(struct inode *inode, u64 start, u64 end,
327 unsigned long old, unsigned long bits)
328 {
329 if ((old & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
330 struct btrfs_root *root = BTRFS_I(inode)->root;
331 unsigned long flags;
332
333 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
334 if (end - start + 1 > root->fs_info->delalloc_bytes) {
335 printk("warning: delalloc account %Lu %Lu\n",
336 end - start + 1, root->fs_info->delalloc_bytes);
337 root->fs_info->delalloc_bytes = 0;
338 BTRFS_I(inode)->delalloc_bytes = 0;
339 } else {
340 root->fs_info->delalloc_bytes -= end - start + 1;
341 BTRFS_I(inode)->delalloc_bytes -= end - start + 1;
342 }
343 if (BTRFS_I(inode)->delalloc_bytes == 0 &&
344 !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
345 list_del_init(&BTRFS_I(inode)->delalloc_inodes);
346 }
347 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
348 }
349 return 0;
350 }
351
352 int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
353 size_t size, struct bio *bio)
354 {
355 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
356 struct btrfs_mapping_tree *map_tree;
357 u64 logical = bio->bi_sector << 9;
358 u64 length = 0;
359 u64 map_length;
360 int ret;
361
362 length = bio->bi_size;
363 map_tree = &root->fs_info->mapping_tree;
364 map_length = length;
365 ret = btrfs_map_block(map_tree, READ, logical,
366 &map_length, NULL, 0);
367
368 if (map_length < length + size) {
369 return 1;
370 }
371 return 0;
372 }
373
374 int __btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
375 int mirror_num)
376 {
377 struct btrfs_root *root = BTRFS_I(inode)->root;
378 int ret = 0;
379
380 ret = btrfs_csum_one_bio(root, inode, bio);
381 BUG_ON(ret);
382
383 return btrfs_map_bio(root, rw, bio, mirror_num, 1);
384 }
385
386 int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
387 int mirror_num)
388 {
389 struct btrfs_root *root = BTRFS_I(inode)->root;
390 int ret = 0;
391
392 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
393 BUG_ON(ret);
394
395 if (btrfs_test_opt(root, NODATASUM) ||
396 btrfs_test_flag(inode, NODATASUM)) {
397 goto mapit;
398 }
399
400 if (!(rw & (1 << BIO_RW))) {
401 btrfs_lookup_bio_sums(root, inode, bio);
402 goto mapit;
403 }
404 return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
405 inode, rw, bio, mirror_num,
406 __btrfs_submit_bio_hook);
407 mapit:
408 return btrfs_map_bio(root, rw, bio, mirror_num, 0);
409 }
410
411 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
412 struct inode *inode, u64 file_offset,
413 struct list_head *list)
414 {
415 struct list_head *cur;
416 struct btrfs_ordered_sum *sum;
417
418 btrfs_set_trans_block_group(trans, inode);
419 list_for_each(cur, list) {
420 sum = list_entry(cur, struct btrfs_ordered_sum, list);
421 btrfs_csum_file_blocks(trans, BTRFS_I(inode)->root,
422 inode, sum);
423 }
424 return 0;
425 }
426
427 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end)
428 {
429 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
430 GFP_NOFS);
431 }
432
433 struct btrfs_writepage_fixup {
434 struct page *page;
435 struct btrfs_work work;
436 };
437
438 /* see btrfs_writepage_start_hook for details on why this is required */
439 void btrfs_writepage_fixup_worker(struct btrfs_work *work)
440 {
441 struct btrfs_writepage_fixup *fixup;
442 struct btrfs_ordered_extent *ordered;
443 struct page *page;
444 struct inode *inode;
445 u64 page_start;
446 u64 page_end;
447
448 fixup = container_of(work, struct btrfs_writepage_fixup, work);
449 page = fixup->page;
450 again:
451 lock_page(page);
452 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
453 ClearPageChecked(page);
454 goto out_page;
455 }
456
457 inode = page->mapping->host;
458 page_start = page_offset(page);
459 page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
460
461 lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
462
463 /* already ordered? We're done */
464 if (test_range_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
465 EXTENT_ORDERED, 0)) {
466 goto out;
467 }
468
469 ordered = btrfs_lookup_ordered_extent(inode, page_start);
470 if (ordered) {
471 unlock_extent(&BTRFS_I(inode)->io_tree, page_start,
472 page_end, GFP_NOFS);
473 unlock_page(page);
474 btrfs_start_ordered_extent(inode, ordered, 1);
475 goto again;
476 }
477
478 btrfs_set_extent_delalloc(inode, page_start, page_end);
479 ClearPageChecked(page);
480 out:
481 unlock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
482 out_page:
483 unlock_page(page);
484 page_cache_release(page);
485 }
486
487 /*
488 * There are a few paths in the higher layers of the kernel that directly
489 * set the page dirty bit without asking the filesystem if it is a
490 * good idea. This causes problems because we want to make sure COW
491 * properly happens and the data=ordered rules are followed.
492 *
493 * In our case any range that doesn't have the EXTENT_ORDERED bit set
494 * hasn't been properly setup for IO. We kick off an async process
495 * to fix it up. The async helper will wait for ordered extents, set
496 * the delalloc bit and make it safe to write the page.
497 */
498 int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
499 {
500 struct inode *inode = page->mapping->host;
501 struct btrfs_writepage_fixup *fixup;
502 struct btrfs_root *root = BTRFS_I(inode)->root;
503 int ret;
504
505 ret = test_range_bit(&BTRFS_I(inode)->io_tree, start, end,
506 EXTENT_ORDERED, 0);
507 if (ret)
508 return 0;
509
510 if (PageChecked(page))
511 return -EAGAIN;
512
513 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
514 if (!fixup)
515 return -EAGAIN;
516
517 SetPageChecked(page);
518 page_cache_get(page);
519 fixup->work.func = btrfs_writepage_fixup_worker;
520 fixup->page = page;
521 btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
522 return -EAGAIN;
523 }
524
525 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
526 {
527 struct btrfs_root *root = BTRFS_I(inode)->root;
528 struct btrfs_trans_handle *trans;
529 struct btrfs_ordered_extent *ordered_extent;
530 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
531 u64 alloc_hint = 0;
532 struct list_head list;
533 struct btrfs_key ins;
534 int ret;
535
536 ret = btrfs_dec_test_ordered_pending(inode, start, end - start + 1);
537 if (!ret)
538 return 0;
539
540 trans = btrfs_join_transaction(root, 1);
541
542 ordered_extent = btrfs_lookup_ordered_extent(inode, start);
543 BUG_ON(!ordered_extent);
544 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags))
545 goto nocow;
546
547 lock_extent(io_tree, ordered_extent->file_offset,
548 ordered_extent->file_offset + ordered_extent->len - 1,
549 GFP_NOFS);
550
551 INIT_LIST_HEAD(&list);
552
553 ins.objectid = ordered_extent->start;
554 ins.offset = ordered_extent->len;
555 ins.type = BTRFS_EXTENT_ITEM_KEY;
556
557 ret = btrfs_alloc_reserved_extent(trans, root, root->root_key.objectid,
558 trans->transid, inode->i_ino,
559 ordered_extent->file_offset, &ins);
560 BUG_ON(ret);
561 mutex_lock(&BTRFS_I(inode)->extent_mutex);
562
563 ret = btrfs_drop_extents(trans, root, inode,
564 ordered_extent->file_offset,
565 ordered_extent->file_offset +
566 ordered_extent->len,
567 ordered_extent->file_offset, &alloc_hint);
568 BUG_ON(ret);
569 ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
570 ordered_extent->file_offset,
571 ordered_extent->start,
572 ordered_extent->len,
573 ordered_extent->len, 0);
574 BUG_ON(ret);
575
576 btrfs_drop_extent_cache(inode, ordered_extent->file_offset,
577 ordered_extent->file_offset +
578 ordered_extent->len - 1);
579 mutex_unlock(&BTRFS_I(inode)->extent_mutex);
580
581 inode->i_blocks += ordered_extent->len >> 9;
582 unlock_extent(io_tree, ordered_extent->file_offset,
583 ordered_extent->file_offset + ordered_extent->len - 1,
584 GFP_NOFS);
585 nocow:
586 add_pending_csums(trans, inode, ordered_extent->file_offset,
587 &ordered_extent->list);
588
589 btrfs_ordered_update_i_size(inode, ordered_extent);
590 btrfs_update_inode(trans, root, inode);
591 btrfs_remove_ordered_extent(inode, ordered_extent);
592
593 /* once for us */
594 btrfs_put_ordered_extent(ordered_extent);
595 /* once for the tree */
596 btrfs_put_ordered_extent(ordered_extent);
597
598 btrfs_end_transaction(trans, root);
599 return 0;
600 }
601
602 int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
603 struct extent_state *state, int uptodate)
604 {
605 return btrfs_finish_ordered_io(page->mapping->host, start, end);
606 }
607
608 struct io_failure_record {
609 struct page *page;
610 u64 start;
611 u64 len;
612 u64 logical;
613 int last_mirror;
614 };
615
616 int btrfs_io_failed_hook(struct bio *failed_bio,
617 struct page *page, u64 start, u64 end,
618 struct extent_state *state)
619 {
620 struct io_failure_record *failrec = NULL;
621 u64 private;
622 struct extent_map *em;
623 struct inode *inode = page->mapping->host;
624 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
625 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
626 struct bio *bio;
627 int num_copies;
628 int ret;
629 int rw;
630 u64 logical;
631
632 ret = get_state_private(failure_tree, start, &private);
633 if (ret) {
634 failrec = kmalloc(sizeof(*failrec), GFP_NOFS);
635 if (!failrec)
636 return -ENOMEM;
637 failrec->start = start;
638 failrec->len = end - start + 1;
639 failrec->last_mirror = 0;
640
641 spin_lock(&em_tree->lock);
642 em = lookup_extent_mapping(em_tree, start, failrec->len);
643 if (em->start > start || em->start + em->len < start) {
644 free_extent_map(em);
645 em = NULL;
646 }
647 spin_unlock(&em_tree->lock);
648
649 if (!em || IS_ERR(em)) {
650 kfree(failrec);
651 return -EIO;
652 }
653 logical = start - em->start;
654 logical = em->block_start + logical;
655 failrec->logical = logical;
656 free_extent_map(em);
657 set_extent_bits(failure_tree, start, end, EXTENT_LOCKED |
658 EXTENT_DIRTY, GFP_NOFS);
659 set_state_private(failure_tree, start,
660 (u64)(unsigned long)failrec);
661 } else {
662 failrec = (struct io_failure_record *)(unsigned long)private;
663 }
664 num_copies = btrfs_num_copies(
665 &BTRFS_I(inode)->root->fs_info->mapping_tree,
666 failrec->logical, failrec->len);
667 failrec->last_mirror++;
668 if (!state) {
669 spin_lock_irq(&BTRFS_I(inode)->io_tree.lock);
670 state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree,
671 failrec->start,
672 EXTENT_LOCKED);
673 if (state && state->start != failrec->start)
674 state = NULL;
675 spin_unlock_irq(&BTRFS_I(inode)->io_tree.lock);
676 }
677 if (!state || failrec->last_mirror > num_copies) {
678 set_state_private(failure_tree, failrec->start, 0);
679 clear_extent_bits(failure_tree, failrec->start,
680 failrec->start + failrec->len - 1,
681 EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
682 kfree(failrec);
683 return -EIO;
684 }
685 bio = bio_alloc(GFP_NOFS, 1);
686 bio->bi_private = state;
687 bio->bi_end_io = failed_bio->bi_end_io;
688 bio->bi_sector = failrec->logical >> 9;
689 bio->bi_bdev = failed_bio->bi_bdev;
690 bio->bi_size = 0;
691 bio_add_page(bio, page, failrec->len, start - page_offset(page));
692 if (failed_bio->bi_rw & (1 << BIO_RW))
693 rw = WRITE;
694 else
695 rw = READ;
696
697 BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio,
698 failrec->last_mirror);
699 return 0;
700 }
701
702 int btrfs_clean_io_failures(struct inode *inode, u64 start)
703 {
704 u64 private;
705 u64 private_failure;
706 struct io_failure_record *failure;
707 int ret;
708
709 private = 0;
710 if (count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
711 (u64)-1, 1, EXTENT_DIRTY)) {
712 ret = get_state_private(&BTRFS_I(inode)->io_failure_tree,
713 start, &private_failure);
714 if (ret == 0) {
715 failure = (struct io_failure_record *)(unsigned long)
716 private_failure;
717 set_state_private(&BTRFS_I(inode)->io_failure_tree,
718 failure->start, 0);
719 clear_extent_bits(&BTRFS_I(inode)->io_failure_tree,
720 failure->start,
721 failure->start + failure->len - 1,
722 EXTENT_DIRTY | EXTENT_LOCKED,
723 GFP_NOFS);
724 kfree(failure);
725 }
726 }
727 return 0;
728 }
729
730 int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
731 struct extent_state *state)
732 {
733 size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
734 struct inode *inode = page->mapping->host;
735 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
736 char *kaddr;
737 u64 private = ~(u32)0;
738 int ret;
739 struct btrfs_root *root = BTRFS_I(inode)->root;
740 u32 csum = ~(u32)0;
741 unsigned long flags;
742
743 if (btrfs_test_opt(root, NODATASUM) ||
744 btrfs_test_flag(inode, NODATASUM))
745 return 0;
746 if (state && state->start == start) {
747 private = state->private;
748 ret = 0;
749 } else {
750 ret = get_state_private(io_tree, start, &private);
751 }
752 local_irq_save(flags);
753 kaddr = kmap_atomic(page, KM_IRQ0);
754 if (ret) {
755 goto zeroit;
756 }
757 csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1);
758 btrfs_csum_final(csum, (char *)&csum);
759 if (csum != private) {
760 goto zeroit;
761 }
762 kunmap_atomic(kaddr, KM_IRQ0);
763 local_irq_restore(flags);
764
765 /* if the io failure tree for this inode is non-empty,
766 * check to see if we've recovered from a failed IO
767 */
768 btrfs_clean_io_failures(inode, start);
769 return 0;
770
771 zeroit:
772 printk("btrfs csum failed ino %lu off %llu csum %u private %Lu\n",
773 page->mapping->host->i_ino, (unsigned long long)start, csum,
774 private);
775 memset(kaddr + offset, 1, end - start + 1);
776 flush_dcache_page(page);
777 kunmap_atomic(kaddr, KM_IRQ0);
778 local_irq_restore(flags);
779 if (private == 0)
780 return 0;
781 return -EIO;
782 }
783
784 /*
785 * This creates an orphan entry for the given inode in case something goes
786 * wrong in the middle of an unlink/truncate.
787 */
788 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
789 {
790 struct btrfs_root *root = BTRFS_I(inode)->root;
791 int ret = 0;
792
793 spin_lock(&root->list_lock);
794
795 /* already on the orphan list, we're good */
796 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
797 spin_unlock(&root->list_lock);
798 return 0;
799 }
800
801 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
802
803 spin_unlock(&root->list_lock);
804
805 /*
806 * insert an orphan item to track this unlinked/truncated file
807 */
808 ret = btrfs_insert_orphan_item(trans, root, inode->i_ino);
809
810 return ret;
811 }
812
813 /*
814 * We have done the truncate/delete so we can go ahead and remove the orphan
815 * item for this particular inode.
816 */
817 int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode)
818 {
819 struct btrfs_root *root = BTRFS_I(inode)->root;
820 int ret = 0;
821
822 spin_lock(&root->list_lock);
823
824 if (list_empty(&BTRFS_I(inode)->i_orphan)) {
825 spin_unlock(&root->list_lock);
826 return 0;
827 }
828
829 list_del_init(&BTRFS_I(inode)->i_orphan);
830 if (!trans) {
831 spin_unlock(&root->list_lock);
832 return 0;
833 }
834
835 spin_unlock(&root->list_lock);
836
837 ret = btrfs_del_orphan_item(trans, root, inode->i_ino);
838
839 return ret;
840 }
841
842 /*
843 * this cleans up any orphans that may be left on the list from the last use
844 * of this root.
845 */
846 void btrfs_orphan_cleanup(struct btrfs_root *root)
847 {
848 struct btrfs_path *path;
849 struct extent_buffer *leaf;
850 struct btrfs_item *item;
851 struct btrfs_key key, found_key;
852 struct btrfs_trans_handle *trans;
853 struct inode *inode;
854 int ret = 0, nr_unlink = 0, nr_truncate = 0;
855
856 /* don't do orphan cleanup if the fs is readonly. */
857 if (root->inode->i_sb->s_flags & MS_RDONLY)
858 return;
859
860 path = btrfs_alloc_path();
861 if (!path)
862 return;
863 path->reada = -1;
864
865 key.objectid = BTRFS_ORPHAN_OBJECTID;
866 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
867 key.offset = (u64)-1;
868
869 trans = btrfs_start_transaction(root, 1);
870 btrfs_set_trans_block_group(trans, root->inode);
871
872 while (1) {
873 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
874 if (ret < 0) {
875 printk(KERN_ERR "Error searching slot for orphan: %d"
876 "\n", ret);
877 break;
878 }
879
880 /*
881 * if ret == 0 means we found what we were searching for, which
882 * is weird, but possible, so only screw with path if we didnt
883 * find the key and see if we have stuff that matches
884 */
885 if (ret > 0) {
886 if (path->slots[0] == 0)
887 break;
888 path->slots[0]--;
889 }
890
891 /* pull out the item */
892 leaf = path->nodes[0];
893 item = btrfs_item_nr(leaf, path->slots[0]);
894 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
895
896 /* make sure the item matches what we want */
897 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
898 break;
899 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
900 break;
901
902 /* release the path since we're done with it */
903 btrfs_release_path(root, path);
904
905 /*
906 * this is where we are basically btrfs_lookup, without the
907 * crossing root thing. we store the inode number in the
908 * offset of the orphan item.
909 */
910 inode = btrfs_iget_locked(root->inode->i_sb,
911 found_key.offset, root);
912 if (!inode)
913 break;
914
915 if (inode->i_state & I_NEW) {
916 BTRFS_I(inode)->root = root;
917
918 /* have to set the location manually */
919 BTRFS_I(inode)->location.objectid = inode->i_ino;
920 BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
921 BTRFS_I(inode)->location.offset = 0;
922
923 btrfs_read_locked_inode(inode);
924 unlock_new_inode(inode);
925 }
926
927 /*
928 * add this inode to the orphan list so btrfs_orphan_del does
929 * the proper thing when we hit it
930 */
931 spin_lock(&root->list_lock);
932 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
933 spin_unlock(&root->list_lock);
934
935 /*
936 * if this is a bad inode, means we actually succeeded in
937 * removing the inode, but not the orphan record, which means
938 * we need to manually delete the orphan since iput will just
939 * do a destroy_inode
940 */
941 if (is_bad_inode(inode)) {
942 btrfs_orphan_del(trans, inode);
943 iput(inode);
944 continue;
945 }
946
947 /* if we have links, this was a truncate, lets do that */
948 if (inode->i_nlink) {
949 nr_truncate++;
950 btrfs_truncate(inode);
951 } else {
952 nr_unlink++;
953 }
954
955 /* this will do delete_inode and everything for us */
956 iput(inode);
957 }
958
959 if (nr_unlink)
960 printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink);
961 if (nr_truncate)
962 printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate);
963
964 btrfs_free_path(path);
965 btrfs_end_transaction(trans, root);
966 }
967
968 void btrfs_read_locked_inode(struct inode *inode)
969 {
970 struct btrfs_path *path;
971 struct extent_buffer *leaf;
972 struct btrfs_inode_item *inode_item;
973 struct btrfs_timespec *tspec;
974 struct btrfs_root *root = BTRFS_I(inode)->root;
975 struct btrfs_key location;
976 u64 alloc_group_block;
977 u32 rdev;
978 int ret;
979
980 path = btrfs_alloc_path();
981 BUG_ON(!path);
982 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
983
984 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
985 if (ret)
986 goto make_bad;
987
988 leaf = path->nodes[0];
989 inode_item = btrfs_item_ptr(leaf, path->slots[0],
990 struct btrfs_inode_item);
991
992 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
993 inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
994 inode->i_uid = btrfs_inode_uid(leaf, inode_item);
995 inode->i_gid = btrfs_inode_gid(leaf, inode_item);
996 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
997
998 tspec = btrfs_inode_atime(inode_item);
999 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
1000 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
1001
1002 tspec = btrfs_inode_mtime(inode_item);
1003 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
1004 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
1005
1006 tspec = btrfs_inode_ctime(inode_item);
1007 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
1008 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
1009
1010 inode->i_blocks = btrfs_inode_nblocks(leaf, inode_item);
1011 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
1012 inode->i_generation = BTRFS_I(inode)->generation;
1013 inode->i_rdev = 0;
1014 rdev = btrfs_inode_rdev(leaf, inode_item);
1015
1016 BTRFS_I(inode)->index_cnt = (u64)-1;
1017
1018 alloc_group_block = btrfs_inode_block_group(leaf, inode_item);
1019 BTRFS_I(inode)->block_group = btrfs_lookup_block_group(root->fs_info,
1020 alloc_group_block);
1021 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
1022 if (!BTRFS_I(inode)->block_group) {
1023 BTRFS_I(inode)->block_group = btrfs_find_block_group(root,
1024 NULL, 0,
1025 BTRFS_BLOCK_GROUP_METADATA, 0);
1026 }
1027 btrfs_free_path(path);
1028 inode_item = NULL;
1029
1030 switch (inode->i_mode & S_IFMT) {
1031 case S_IFREG:
1032 inode->i_mapping->a_ops = &btrfs_aops;
1033 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
1034 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
1035 inode->i_fop = &btrfs_file_operations;
1036 inode->i_op = &btrfs_file_inode_operations;
1037 break;
1038 case S_IFDIR:
1039 inode->i_fop = &btrfs_dir_file_operations;
1040 if (root == root->fs_info->tree_root)
1041 inode->i_op = &btrfs_dir_ro_inode_operations;
1042 else
1043 inode->i_op = &btrfs_dir_inode_operations;
1044 break;
1045 case S_IFLNK:
1046 inode->i_op = &btrfs_symlink_inode_operations;
1047 inode->i_mapping->a_ops = &btrfs_symlink_aops;
1048 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
1049 break;
1050 default:
1051 init_special_inode(inode, inode->i_mode, rdev);
1052 break;
1053 }
1054 return;
1055
1056 make_bad:
1057 btrfs_free_path(path);
1058 make_bad_inode(inode);
1059 }
1060
1061 static void fill_inode_item(struct btrfs_trans_handle *trans,
1062 struct extent_buffer *leaf,
1063 struct btrfs_inode_item *item,
1064 struct inode *inode)
1065 {
1066 btrfs_set_inode_uid(leaf, item, inode->i_uid);
1067 btrfs_set_inode_gid(leaf, item, inode->i_gid);
1068 btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size);
1069 btrfs_set_inode_mode(leaf, item, inode->i_mode);
1070 btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
1071
1072 btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
1073 inode->i_atime.tv_sec);
1074 btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
1075 inode->i_atime.tv_nsec);
1076
1077 btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
1078 inode->i_mtime.tv_sec);
1079 btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
1080 inode->i_mtime.tv_nsec);
1081
1082 btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
1083 inode->i_ctime.tv_sec);
1084 btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
1085 inode->i_ctime.tv_nsec);
1086
1087 btrfs_set_inode_nblocks(leaf, item, inode->i_blocks);
1088 btrfs_set_inode_generation(leaf, item, BTRFS_I(inode)->generation);
1089 btrfs_set_inode_transid(leaf, item, trans->transid);
1090 btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
1091 btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
1092 btrfs_set_inode_block_group(leaf, item,
1093 BTRFS_I(inode)->block_group->key.objectid);
1094 }
1095
1096 int noinline btrfs_update_inode(struct btrfs_trans_handle *trans,
1097 struct btrfs_root *root,
1098 struct inode *inode)
1099 {
1100 struct btrfs_inode_item *inode_item;
1101 struct btrfs_path *path;
1102 struct extent_buffer *leaf;
1103 int ret;
1104
1105 path = btrfs_alloc_path();
1106 BUG_ON(!path);
1107 ret = btrfs_lookup_inode(trans, root, path,
1108 &BTRFS_I(inode)->location, 1);
1109 if (ret) {
1110 if (ret > 0)
1111 ret = -ENOENT;
1112 goto failed;
1113 }
1114
1115 leaf = path->nodes[0];
1116 inode_item = btrfs_item_ptr(leaf, path->slots[0],
1117 struct btrfs_inode_item);
1118
1119 fill_inode_item(trans, leaf, inode_item, inode);
1120 btrfs_mark_buffer_dirty(leaf);
1121 btrfs_set_inode_last_trans(trans, inode);
1122 ret = 0;
1123 failed:
1124 btrfs_free_path(path);
1125 return ret;
1126 }
1127
1128
1129 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
1130 struct btrfs_root *root,
1131 struct inode *dir, struct inode *inode,
1132 const char *name, int name_len)
1133 {
1134 struct btrfs_path *path;
1135 int ret = 0;
1136 struct extent_buffer *leaf;
1137 struct btrfs_dir_item *di;
1138 struct btrfs_key key;
1139 u64 index;
1140
1141 path = btrfs_alloc_path();
1142 if (!path) {
1143 ret = -ENOMEM;
1144 goto err;
1145 }
1146
1147 di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
1148 name, name_len, -1);
1149 if (IS_ERR(di)) {
1150 ret = PTR_ERR(di);
1151 goto err;
1152 }
1153 if (!di) {
1154 ret = -ENOENT;
1155 goto err;
1156 }
1157 leaf = path->nodes[0];
1158 btrfs_dir_item_key_to_cpu(leaf, di, &key);
1159 ret = btrfs_delete_one_dir_name(trans, root, path, di);
1160 if (ret)
1161 goto err;
1162 btrfs_release_path(root, path);
1163
1164 ret = btrfs_del_inode_ref(trans, root, name, name_len,
1165 inode->i_ino,
1166 dir->i_ino, &index);
1167 if (ret) {
1168 printk("failed to delete reference to %.*s, "
1169 "inode %lu parent %lu\n", name_len, name,
1170 inode->i_ino, dir->i_ino);
1171 goto err;
1172 }
1173
1174 di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
1175 index, name, name_len, -1);
1176 if (IS_ERR(di)) {
1177 ret = PTR_ERR(di);
1178 goto err;
1179 }
1180 if (!di) {
1181 ret = -ENOENT;
1182 goto err;
1183 }
1184 ret = btrfs_delete_one_dir_name(trans, root, path, di);
1185 btrfs_release_path(root, path);
1186
1187 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
1188 inode, dir->i_ino);
1189 BUG_ON(ret != 0 && ret != -ENOENT);
1190 if (ret != -ENOENT)
1191 BTRFS_I(dir)->log_dirty_trans = trans->transid;
1192
1193 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
1194 dir, index);
1195 BUG_ON(ret);
1196 err:
1197 btrfs_free_path(path);
1198 if (ret)
1199 goto out;
1200
1201 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
1202 inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
1203 btrfs_update_inode(trans, root, dir);
1204 btrfs_drop_nlink(inode);
1205 ret = btrfs_update_inode(trans, root, inode);
1206 dir->i_sb->s_dirt = 1;
1207 out:
1208 return ret;
1209 }
1210
1211 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
1212 {
1213 struct btrfs_root *root;
1214 struct btrfs_trans_handle *trans;
1215 struct inode *inode = dentry->d_inode;
1216 int ret;
1217 unsigned long nr = 0;
1218
1219 root = BTRFS_I(dir)->root;
1220
1221 ret = btrfs_check_free_space(root, 1, 1);
1222 if (ret)
1223 goto fail;
1224
1225 trans = btrfs_start_transaction(root, 1);
1226
1227 btrfs_set_trans_block_group(trans, dir);
1228 ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
1229 dentry->d_name.name, dentry->d_name.len);
1230
1231 if (inode->i_nlink == 0)
1232 ret = btrfs_orphan_add(trans, inode);
1233
1234 nr = trans->blocks_used;
1235
1236 btrfs_end_transaction_throttle(trans, root);
1237 fail:
1238 btrfs_btree_balance_dirty(root, nr);
1239 return ret;
1240 }
1241
1242 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
1243 {
1244 struct inode *inode = dentry->d_inode;
1245 int err = 0;
1246 int ret;
1247 struct btrfs_root *root = BTRFS_I(dir)->root;
1248 struct btrfs_trans_handle *trans;
1249 unsigned long nr = 0;
1250
1251 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
1252 return -ENOTEMPTY;
1253 }
1254
1255 ret = btrfs_check_free_space(root, 1, 1);
1256 if (ret)
1257 goto fail;
1258
1259 trans = btrfs_start_transaction(root, 1);
1260 btrfs_set_trans_block_group(trans, dir);
1261
1262 err = btrfs_orphan_add(trans, inode);
1263 if (err)
1264 goto fail_trans;
1265
1266 /* now the directory is empty */
1267 err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
1268 dentry->d_name.name, dentry->d_name.len);
1269 if (!err) {
1270 btrfs_i_size_write(inode, 0);
1271 }
1272
1273 fail_trans:
1274 nr = trans->blocks_used;
1275 ret = btrfs_end_transaction_throttle(trans, root);
1276 fail:
1277 btrfs_btree_balance_dirty(root, nr);
1278
1279 if (ret && !err)
1280 err = ret;
1281 return err;
1282 }
1283
1284 /*
1285 * this can truncate away extent items, csum items and directory items.
1286 * It starts at a high offset and removes keys until it can't find
1287 * any higher than i_size.
1288 *
1289 * csum items that cross the new i_size are truncated to the new size
1290 * as well.
1291 *
1292 * min_type is the minimum key type to truncate down to. If set to 0, this
1293 * will kill all the items on this inode, including the INODE_ITEM_KEY.
1294 */
1295 noinline int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
1296 struct btrfs_root *root,
1297 struct inode *inode,
1298 u64 new_size, u32 min_type)
1299 {
1300 int ret;
1301 struct btrfs_path *path;
1302 struct btrfs_key key;
1303 struct btrfs_key found_key;
1304 u32 found_type;
1305 struct extent_buffer *leaf;
1306 struct btrfs_file_extent_item *fi;
1307 u64 extent_start = 0;
1308 u64 extent_num_bytes = 0;
1309 u64 item_end = 0;
1310 u64 root_gen = 0;
1311 u64 root_owner = 0;
1312 int found_extent;
1313 int del_item;
1314 int pending_del_nr = 0;
1315 int pending_del_slot = 0;
1316 int extent_type = -1;
1317 u64 mask = root->sectorsize - 1;
1318
1319 if (root->ref_cows)
1320 btrfs_drop_extent_cache(inode,
1321 new_size & (~mask), (u64)-1);
1322 path = btrfs_alloc_path();
1323 path->reada = -1;
1324 BUG_ON(!path);
1325
1326 /* FIXME, add redo link to tree so we don't leak on crash */
1327 key.objectid = inode->i_ino;
1328 key.offset = (u64)-1;
1329 key.type = (u8)-1;
1330
1331 btrfs_init_path(path);
1332 search_again:
1333 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1334 if (ret < 0) {
1335 goto error;
1336 }
1337 if (ret > 0) {
1338 /* there are no items in the tree for us to truncate, we're
1339 * done
1340 */
1341 if (path->slots[0] == 0) {
1342 ret = 0;
1343 goto error;
1344 }
1345 path->slots[0]--;
1346 }
1347
1348 while(1) {
1349 fi = NULL;
1350 leaf = path->nodes[0];
1351 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1352 found_type = btrfs_key_type(&found_key);
1353
1354 if (found_key.objectid != inode->i_ino)
1355 break;
1356
1357 if (found_type < min_type)
1358 break;
1359
1360 item_end = found_key.offset;
1361 if (found_type == BTRFS_EXTENT_DATA_KEY) {
1362 fi = btrfs_item_ptr(leaf, path->slots[0],
1363 struct btrfs_file_extent_item);
1364 extent_type = btrfs_file_extent_type(leaf, fi);
1365 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
1366 item_end +=
1367 btrfs_file_extent_num_bytes(leaf, fi);
1368 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1369 struct btrfs_item *item = btrfs_item_nr(leaf,
1370 path->slots[0]);
1371 item_end += btrfs_file_extent_inline_len(leaf,
1372 item);
1373 }
1374 item_end--;
1375 }
1376 if (found_type == BTRFS_CSUM_ITEM_KEY) {
1377 ret = btrfs_csum_truncate(trans, root, path,
1378 new_size);
1379 BUG_ON(ret);
1380 }
1381 if (item_end < new_size) {
1382 if (found_type == BTRFS_DIR_ITEM_KEY) {
1383 found_type = BTRFS_INODE_ITEM_KEY;
1384 } else if (found_type == BTRFS_EXTENT_ITEM_KEY) {
1385 found_type = BTRFS_CSUM_ITEM_KEY;
1386 } else if (found_type == BTRFS_EXTENT_DATA_KEY) {
1387 found_type = BTRFS_XATTR_ITEM_KEY;
1388 } else if (found_type == BTRFS_XATTR_ITEM_KEY) {
1389 found_type = BTRFS_INODE_REF_KEY;
1390 } else if (found_type) {
1391 found_type--;
1392 } else {
1393 break;
1394 }
1395 btrfs_set_key_type(&key, found_type);
1396 goto next;
1397 }
1398 if (found_key.offset >= new_size)
1399 del_item = 1;
1400 else
1401 del_item = 0;
1402 found_extent = 0;
1403
1404 /* FIXME, shrink the extent if the ref count is only 1 */
1405 if (found_type != BTRFS_EXTENT_DATA_KEY)
1406 goto delete;
1407
1408 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
1409 u64 num_dec;
1410 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
1411 if (!del_item) {
1412 u64 orig_num_bytes =
1413 btrfs_file_extent_num_bytes(leaf, fi);
1414 extent_num_bytes = new_size -
1415 found_key.offset + root->sectorsize - 1;
1416 extent_num_bytes = extent_num_bytes &
1417 ~((u64)root->sectorsize - 1);
1418 btrfs_set_file_extent_num_bytes(leaf, fi,
1419 extent_num_bytes);
1420 num_dec = (orig_num_bytes -
1421 extent_num_bytes);
1422 if (root->ref_cows && extent_start != 0)
1423 dec_i_blocks(inode, num_dec);
1424 btrfs_mark_buffer_dirty(leaf);
1425 } else {
1426 extent_num_bytes =
1427 btrfs_file_extent_disk_num_bytes(leaf,
1428 fi);
1429 /* FIXME blocksize != 4096 */
1430 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
1431 if (extent_start != 0) {
1432 found_extent = 1;
1433 if (root->ref_cows)
1434 dec_i_blocks(inode, num_dec);
1435 }
1436 if (root->ref_cows) {
1437 root_gen =
1438 btrfs_header_generation(leaf);
1439 }
1440 root_owner = btrfs_header_owner(leaf);
1441 }
1442 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1443 if (!del_item) {
1444 u32 size = new_size - found_key.offset;
1445
1446 if (root->ref_cows) {
1447 dec_i_blocks(inode, item_end + 1 -
1448 found_key.offset - size);
1449 }
1450 size =
1451 btrfs_file_extent_calc_inline_size(size);
1452 ret = btrfs_truncate_item(trans, root, path,
1453 size, 1);
1454 BUG_ON(ret);
1455 } else if (root->ref_cows) {
1456 dec_i_blocks(inode, item_end + 1 -
1457 found_key.offset);
1458 }
1459 }
1460 delete:
1461 if (del_item) {
1462 if (!pending_del_nr) {
1463 /* no pending yet, add ourselves */
1464 pending_del_slot = path->slots[0];
1465 pending_del_nr = 1;
1466 } else if (pending_del_nr &&
1467 path->slots[0] + 1 == pending_del_slot) {
1468 /* hop on the pending chunk */
1469 pending_del_nr++;
1470 pending_del_slot = path->slots[0];
1471 } else {
1472 printk("bad pending slot %d pending_del_nr %d pending_del_slot %d\n", path->slots[0], pending_del_nr, pending_del_slot);
1473 }
1474 } else {
1475 break;
1476 }
1477 if (found_extent) {
1478 ret = btrfs_free_extent(trans, root, extent_start,
1479 extent_num_bytes,
1480 root_owner,
1481 root_gen, inode->i_ino,
1482 found_key.offset, 0);
1483 BUG_ON(ret);
1484 }
1485 next:
1486 if (path->slots[0] == 0) {
1487 if (pending_del_nr)
1488 goto del_pending;
1489 btrfs_release_path(root, path);
1490 goto search_again;
1491 }
1492
1493 path->slots[0]--;
1494 if (pending_del_nr &&
1495 path->slots[0] + 1 != pending_del_slot) {
1496 struct btrfs_key debug;
1497 del_pending:
1498 btrfs_item_key_to_cpu(path->nodes[0], &debug,
1499 pending_del_slot);
1500 ret = btrfs_del_items(trans, root, path,
1501 pending_del_slot,
1502 pending_del_nr);
1503 BUG_ON(ret);
1504 pending_del_nr = 0;
1505 btrfs_release_path(root, path);
1506 goto search_again;
1507 }
1508 }
1509 ret = 0;
1510 error:
1511 if (pending_del_nr) {
1512 ret = btrfs_del_items(trans, root, path, pending_del_slot,
1513 pending_del_nr);
1514 }
1515 btrfs_free_path(path);
1516 inode->i_sb->s_dirt = 1;
1517 return ret;
1518 }
1519
1520 /*
1521 * taken from block_truncate_page, but does cow as it zeros out
1522 * any bytes left in the last page in the file.
1523 */
1524 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
1525 {
1526 struct inode *inode = mapping->host;
1527 struct btrfs_root *root = BTRFS_I(inode)->root;
1528 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1529 struct btrfs_ordered_extent *ordered;
1530 char *kaddr;
1531 u32 blocksize = root->sectorsize;
1532 pgoff_t index = from >> PAGE_CACHE_SHIFT;
1533 unsigned offset = from & (PAGE_CACHE_SIZE-1);
1534 struct page *page;
1535 int ret = 0;
1536 u64 page_start;
1537 u64 page_end;
1538
1539 if ((offset & (blocksize - 1)) == 0)
1540 goto out;
1541
1542 ret = -ENOMEM;
1543 again:
1544 page = grab_cache_page(mapping, index);
1545 if (!page)
1546 goto out;
1547
1548 page_start = page_offset(page);
1549 page_end = page_start + PAGE_CACHE_SIZE - 1;
1550
1551 if (!PageUptodate(page)) {
1552 ret = btrfs_readpage(NULL, page);
1553 lock_page(page);
1554 if (page->mapping != mapping) {
1555 unlock_page(page);
1556 page_cache_release(page);
1557 goto again;
1558 }
1559 if (!PageUptodate(page)) {
1560 ret = -EIO;
1561 goto out_unlock;
1562 }
1563 }
1564 wait_on_page_writeback(page);
1565
1566 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
1567 set_page_extent_mapped(page);
1568
1569 ordered = btrfs_lookup_ordered_extent(inode, page_start);
1570 if (ordered) {
1571 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
1572 unlock_page(page);
1573 page_cache_release(page);
1574 btrfs_start_ordered_extent(inode, ordered, 1);
1575 btrfs_put_ordered_extent(ordered);
1576 goto again;
1577 }
1578
1579 btrfs_set_extent_delalloc(inode, page_start, page_end);
1580 ret = 0;
1581 if (offset != PAGE_CACHE_SIZE) {
1582 kaddr = kmap(page);
1583 memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
1584 flush_dcache_page(page);
1585 kunmap(page);
1586 }
1587 ClearPageChecked(page);
1588 set_page_dirty(page);
1589 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
1590
1591 out_unlock:
1592 unlock_page(page);
1593 page_cache_release(page);
1594 out:
1595 return ret;
1596 }
1597
1598 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
1599 {
1600 struct inode *inode = dentry->d_inode;
1601 int err;
1602
1603 err = inode_change_ok(inode, attr);
1604 if (err)
1605 return err;
1606
1607 if (S_ISREG(inode->i_mode) &&
1608 attr->ia_valid & ATTR_SIZE && attr->ia_size > inode->i_size) {
1609 struct btrfs_trans_handle *trans;
1610 struct btrfs_root *root = BTRFS_I(inode)->root;
1611 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1612
1613 u64 mask = root->sectorsize - 1;
1614 u64 hole_start = (inode->i_size + mask) & ~mask;
1615 u64 block_end = (attr->ia_size + mask) & ~mask;
1616 u64 hole_size;
1617 u64 alloc_hint = 0;
1618
1619 if (attr->ia_size <= hole_start)
1620 goto out;
1621
1622 err = btrfs_check_free_space(root, 1, 0);
1623 if (err)
1624 goto fail;
1625
1626 btrfs_truncate_page(inode->i_mapping, inode->i_size);
1627
1628 hole_size = block_end - hole_start;
1629 while(1) {
1630 struct btrfs_ordered_extent *ordered;
1631 btrfs_wait_ordered_range(inode, hole_start, hole_size);
1632
1633 lock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
1634 ordered = btrfs_lookup_ordered_extent(inode, hole_start);
1635 if (ordered) {
1636 unlock_extent(io_tree, hole_start,
1637 block_end - 1, GFP_NOFS);
1638 btrfs_put_ordered_extent(ordered);
1639 } else {
1640 break;
1641 }
1642 }
1643
1644 trans = btrfs_start_transaction(root, 1);
1645 btrfs_set_trans_block_group(trans, inode);
1646 mutex_lock(&BTRFS_I(inode)->extent_mutex);
1647 err = btrfs_drop_extents(trans, root, inode,
1648 hole_start, block_end, hole_start,
1649 &alloc_hint);
1650
1651 if (alloc_hint != EXTENT_MAP_INLINE) {
1652 err = btrfs_insert_file_extent(trans, root,
1653 inode->i_ino,
1654 hole_start, 0, 0,
1655 hole_size, 0);
1656 btrfs_drop_extent_cache(inode, hole_start,
1657 (u64)-1);
1658 btrfs_check_file(root, inode);
1659 }
1660 mutex_unlock(&BTRFS_I(inode)->extent_mutex);
1661 btrfs_end_transaction(trans, root);
1662 unlock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
1663 if (err)
1664 return err;
1665 }
1666 out:
1667 err = inode_setattr(inode, attr);
1668
1669 if (!err && ((attr->ia_valid & ATTR_MODE)))
1670 err = btrfs_acl_chmod(inode);
1671 fail:
1672 return err;
1673 }
1674
1675 void btrfs_delete_inode(struct inode *inode)
1676 {
1677 struct btrfs_trans_handle *trans;
1678 struct btrfs_root *root = BTRFS_I(inode)->root;
1679 unsigned long nr;
1680 int ret;
1681
1682 truncate_inode_pages(&inode->i_data, 0);
1683 if (is_bad_inode(inode)) {
1684 btrfs_orphan_del(NULL, inode);
1685 goto no_delete;
1686 }
1687 btrfs_wait_ordered_range(inode, 0, (u64)-1);
1688
1689 btrfs_i_size_write(inode, 0);
1690 trans = btrfs_start_transaction(root, 1);
1691
1692 btrfs_set_trans_block_group(trans, inode);
1693 ret = btrfs_truncate_inode_items(trans, root, inode, inode->i_size, 0);
1694 if (ret) {
1695 btrfs_orphan_del(NULL, inode);
1696 goto no_delete_lock;
1697 }
1698
1699 btrfs_orphan_del(trans, inode);
1700
1701 nr = trans->blocks_used;
1702 clear_inode(inode);
1703
1704 btrfs_end_transaction(trans, root);
1705 btrfs_btree_balance_dirty(root, nr);
1706 return;
1707
1708 no_delete_lock:
1709 nr = trans->blocks_used;
1710 btrfs_end_transaction(trans, root);
1711 btrfs_btree_balance_dirty(root, nr);
1712 no_delete:
1713 clear_inode(inode);
1714 }
1715
1716 /*
1717 * this returns the key found in the dir entry in the location pointer.
1718 * If no dir entries were found, location->objectid is 0.
1719 */
1720 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
1721 struct btrfs_key *location)
1722 {
1723 const char *name = dentry->d_name.name;
1724 int namelen = dentry->d_name.len;
1725 struct btrfs_dir_item *di;
1726 struct btrfs_path *path;
1727 struct btrfs_root *root = BTRFS_I(dir)->root;
1728 int ret = 0;
1729
1730 path = btrfs_alloc_path();
1731 BUG_ON(!path);
1732
1733 di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
1734 namelen, 0);
1735 if (IS_ERR(di))
1736 ret = PTR_ERR(di);
1737 if (!di || IS_ERR(di)) {
1738 goto out_err;
1739 }
1740 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
1741 out:
1742 btrfs_free_path(path);
1743 return ret;
1744 out_err:
1745 location->objectid = 0;
1746 goto out;
1747 }
1748
1749 /*
1750 * when we hit a tree root in a directory, the btrfs part of the inode
1751 * needs to be changed to reflect the root directory of the tree root. This
1752 * is kind of like crossing a mount point.
1753 */
1754 static int fixup_tree_root_location(struct btrfs_root *root,
1755 struct btrfs_key *location,
1756 struct btrfs_root **sub_root,
1757 struct dentry *dentry)
1758 {
1759 struct btrfs_root_item *ri;
1760
1761 if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
1762 return 0;
1763 if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1764 return 0;
1765
1766 *sub_root = btrfs_read_fs_root(root->fs_info, location,
1767 dentry->d_name.name,
1768 dentry->d_name.len);
1769 if (IS_ERR(*sub_root))
1770 return PTR_ERR(*sub_root);
1771
1772 ri = &(*sub_root)->root_item;
1773 location->objectid = btrfs_root_dirid(ri);
1774 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
1775 location->offset = 0;
1776
1777 return 0;
1778 }
1779
1780 static noinline void init_btrfs_i(struct inode *inode)
1781 {
1782 struct btrfs_inode *bi = BTRFS_I(inode);
1783
1784 bi->i_acl = NULL;
1785 bi->i_default_acl = NULL;
1786
1787 bi->generation = 0;
1788 bi->last_trans = 0;
1789 bi->logged_trans = 0;
1790 bi->delalloc_bytes = 0;
1791 bi->disk_i_size = 0;
1792 bi->flags = 0;
1793 bi->index_cnt = (u64)-1;
1794 bi->log_dirty_trans = 0;
1795 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
1796 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
1797 inode->i_mapping, GFP_NOFS);
1798 extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
1799 inode->i_mapping, GFP_NOFS);
1800 INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
1801 btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
1802 mutex_init(&BTRFS_I(inode)->csum_mutex);
1803 mutex_init(&BTRFS_I(inode)->extent_mutex);
1804 mutex_init(&BTRFS_I(inode)->log_mutex);
1805 }
1806
1807 static int btrfs_init_locked_inode(struct inode *inode, void *p)
1808 {
1809 struct btrfs_iget_args *args = p;
1810 inode->i_ino = args->ino;
1811 init_btrfs_i(inode);
1812 BTRFS_I(inode)->root = args->root;
1813 return 0;
1814 }
1815
1816 static int btrfs_find_actor(struct inode *inode, void *opaque)
1817 {
1818 struct btrfs_iget_args *args = opaque;
1819 return (args->ino == inode->i_ino &&
1820 args->root == BTRFS_I(inode)->root);
1821 }
1822
1823 struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
1824 struct btrfs_root *root)
1825 {
1826 struct inode *inode;
1827 struct btrfs_iget_args args;
1828 args.ino = objectid;
1829 args.root = root;
1830
1831 inode = iget5_locked(s, objectid, btrfs_find_actor,
1832 btrfs_init_locked_inode,
1833 (void *)&args);
1834 return inode;
1835 }
1836
1837 /* Get an inode object given its location and corresponding root.
1838 * Returns in *is_new if the inode was read from disk
1839 */
1840 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
1841 struct btrfs_root *root, int *is_new)
1842 {
1843 struct inode *inode;
1844
1845 inode = btrfs_iget_locked(s, location->objectid, root);
1846 if (!inode)
1847 return ERR_PTR(-EACCES);
1848
1849 if (inode->i_state & I_NEW) {
1850 BTRFS_I(inode)->root = root;
1851 memcpy(&BTRFS_I(inode)->location, location, sizeof(*location));
1852 btrfs_read_locked_inode(inode);
1853 unlock_new_inode(inode);
1854 if (is_new)
1855 *is_new = 1;
1856 } else {
1857 if (is_new)
1858 *is_new = 0;
1859 }
1860
1861 return inode;
1862 }
1863
1864 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
1865 struct nameidata *nd)
1866 {
1867 struct inode * inode;
1868 struct btrfs_inode *bi = BTRFS_I(dir);
1869 struct btrfs_root *root = bi->root;
1870 struct btrfs_root *sub_root = root;
1871 struct btrfs_key location;
1872 int ret, new, do_orphan = 0;
1873
1874 if (dentry->d_name.len > BTRFS_NAME_LEN)
1875 return ERR_PTR(-ENAMETOOLONG);
1876
1877 ret = btrfs_inode_by_name(dir, dentry, &location);
1878
1879 if (ret < 0)
1880 return ERR_PTR(ret);
1881
1882 inode = NULL;
1883 if (location.objectid) {
1884 ret = fixup_tree_root_location(root, &location, &sub_root,
1885 dentry);
1886 if (ret < 0)
1887 return ERR_PTR(ret);
1888 if (ret > 0)
1889 return ERR_PTR(-ENOENT);
1890 inode = btrfs_iget(dir->i_sb, &location, sub_root, &new);
1891 if (IS_ERR(inode))
1892 return ERR_CAST(inode);
1893
1894 /* the inode and parent dir are two different roots */
1895 if (new && root != sub_root) {
1896 igrab(inode);
1897 sub_root->inode = inode;
1898 do_orphan = 1;
1899 }
1900 }
1901
1902 if (unlikely(do_orphan))
1903 btrfs_orphan_cleanup(sub_root);
1904
1905 return d_splice_alias(inode, dentry);
1906 }
1907
1908 static unsigned char btrfs_filetype_table[] = {
1909 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
1910 };
1911
1912 static int btrfs_real_readdir(struct file *filp, void *dirent,
1913 filldir_t filldir)
1914 {
1915 struct inode *inode = filp->f_dentry->d_inode;
1916 struct btrfs_root *root = BTRFS_I(inode)->root;
1917 struct btrfs_item *item;
1918 struct btrfs_dir_item *di;
1919 struct btrfs_key key;
1920 struct btrfs_key found_key;
1921 struct btrfs_path *path;
1922 int ret;
1923 u32 nritems;
1924 struct extent_buffer *leaf;
1925 int slot;
1926 int advance;
1927 unsigned char d_type;
1928 int over = 0;
1929 u32 di_cur;
1930 u32 di_total;
1931 u32 di_len;
1932 int key_type = BTRFS_DIR_INDEX_KEY;
1933 char tmp_name[32];
1934 char *name_ptr;
1935 int name_len;
1936
1937 /* FIXME, use a real flag for deciding about the key type */
1938 if (root->fs_info->tree_root == root)
1939 key_type = BTRFS_DIR_ITEM_KEY;
1940
1941 /* special case for "." */
1942 if (filp->f_pos == 0) {
1943 over = filldir(dirent, ".", 1,
1944 1, inode->i_ino,
1945 DT_DIR);
1946 if (over)
1947 return 0;
1948 filp->f_pos = 1;
1949 }
1950 /* special case for .., just use the back ref */
1951 if (filp->f_pos == 1) {
1952 u64 pino = parent_ino(filp->f_path.dentry);
1953 over = filldir(dirent, "..", 2,
1954 2, pino, DT_DIR);
1955 if (over)
1956 return 0;
1957 filp->f_pos = 2;
1958 }
1959
1960 path = btrfs_alloc_path();
1961 path->reada = 2;
1962
1963 btrfs_set_key_type(&key, key_type);
1964 key.offset = filp->f_pos;
1965 key.objectid = inode->i_ino;
1966
1967 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1968 if (ret < 0)
1969 goto err;
1970 advance = 0;
1971
1972 while (1) {
1973 leaf = path->nodes[0];
1974 nritems = btrfs_header_nritems(leaf);
1975 slot = path->slots[0];
1976 if (advance || slot >= nritems) {
1977 if (slot >= nritems - 1) {
1978 ret = btrfs_next_leaf(root, path);
1979 if (ret)
1980 break;
1981 leaf = path->nodes[0];
1982 nritems = btrfs_header_nritems(leaf);
1983 slot = path->slots[0];
1984 } else {
1985 slot++;
1986 path->slots[0]++;
1987 }
1988 }
1989 advance = 1;
1990 item = btrfs_item_nr(leaf, slot);
1991 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1992
1993 if (found_key.objectid != key.objectid)
1994 break;
1995 if (btrfs_key_type(&found_key) != key_type)
1996 break;
1997 if (found_key.offset < filp->f_pos)
1998 continue;
1999
2000 filp->f_pos = found_key.offset;
2001
2002 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
2003 di_cur = 0;
2004 di_total = btrfs_item_size(leaf, item);
2005
2006 while (di_cur < di_total) {
2007 struct btrfs_key location;
2008
2009 name_len = btrfs_dir_name_len(leaf, di);
2010 if (name_len <= sizeof(tmp_name)) {
2011 name_ptr = tmp_name;
2012 } else {
2013 name_ptr = kmalloc(name_len, GFP_NOFS);
2014 if (!name_ptr) {
2015 ret = -ENOMEM;
2016 goto err;
2017 }
2018 }
2019 read_extent_buffer(leaf, name_ptr,
2020 (unsigned long)(di + 1), name_len);
2021
2022 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
2023 btrfs_dir_item_key_to_cpu(leaf, di, &location);
2024 over = filldir(dirent, name_ptr, name_len,
2025 found_key.offset, location.objectid,
2026 d_type);
2027
2028 if (name_ptr != tmp_name)
2029 kfree(name_ptr);
2030
2031 if (over)
2032 goto nopos;
2033
2034 di_len = btrfs_dir_name_len(leaf, di) +
2035 btrfs_dir_data_len(leaf, di) + sizeof(*di);
2036 di_cur += di_len;
2037 di = (struct btrfs_dir_item *)((char *)di + di_len);
2038 }
2039 }
2040
2041 /* Reached end of directory/root. Bump pos past the last item. */
2042 if (key_type == BTRFS_DIR_INDEX_KEY)
2043 filp->f_pos = INT_LIMIT(typeof(filp->f_pos));
2044 else
2045 filp->f_pos++;
2046 nopos:
2047 ret = 0;
2048 err:
2049 btrfs_free_path(path);
2050 return ret;
2051 }
2052
2053 /* Kernels earlier than 2.6.28 still have the NFS deadlock where nfsd
2054 will call the file system's ->lookup() method from within its
2055 filldir callback, which in turn was called from the file system's
2056 ->readdir() method. And will deadlock for many file systems. */
2057 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,28)
2058
2059 struct nfshack_dirent {
2060 u64 ino;
2061 loff_t offset;
2062 int namlen;
2063 unsigned int d_type;
2064 char name[];
2065 };
2066
2067 struct nfshack_readdir {
2068 char *dirent;
2069 size_t used;
2070 int full;
2071 };
2072
2073
2074
2075 static int btrfs_nfshack_filldir(void *__buf, const char *name, int namlen,
2076 loff_t offset, u64 ino, unsigned int d_type)
2077 {
2078 struct nfshack_readdir *buf = __buf;
2079 struct nfshack_dirent *de = (void *)(buf->dirent + buf->used);
2080 unsigned int reclen;
2081
2082 reclen = ALIGN(sizeof(struct nfshack_dirent) + namlen, sizeof(u64));
2083 if (buf->used + reclen > PAGE_SIZE) {
2084 buf->full = 1;
2085 return -EINVAL;
2086 }
2087
2088 de->namlen = namlen;
2089 de->offset = offset;
2090 de->ino = ino;
2091 de->d_type = d_type;
2092 memcpy(de->name, name, namlen);
2093 buf->used += reclen;
2094
2095 return 0;
2096 }
2097
2098 static int btrfs_nfshack_readdir(struct file *file, void *dirent,
2099 filldir_t filldir)
2100 {
2101 struct nfshack_readdir buf;
2102 struct nfshack_dirent *de;
2103 int err;
2104 int size;
2105 loff_t offset;
2106
2107 buf.dirent = (void *)__get_free_page(GFP_KERNEL);
2108 if (!buf.dirent)
2109 return -ENOMEM;
2110
2111 offset = file->f_pos;
2112
2113 do {
2114 unsigned int reclen;
2115
2116 buf.used = 0;
2117 buf.full = 0;
2118 err = btrfs_real_readdir(file, &buf, btrfs_nfshack_filldir);
2119 if (err)
2120 break;
2121
2122 size = buf.used;
2123
2124 if (!size)
2125 break;
2126
2127 de = (struct nfshack_dirent *)buf.dirent;
2128 while (size > 0) {
2129 offset = de->offset;
2130
2131 if (filldir(dirent, de->name, de->namlen, de->offset,
2132 de->ino, de->d_type))
2133 goto done;
2134 offset = file->f_pos;
2135
2136 reclen = ALIGN(sizeof(*de) + de->namlen,
2137 sizeof(u64));
2138 size -= reclen;
2139 de = (struct nfshack_dirent *)((char *)de + reclen);
2140 }
2141 } while (buf.full);
2142
2143 done:
2144 free_page((unsigned long)buf.dirent);
2145 file->f_pos = offset;
2146
2147 return err;
2148 }
2149 #endif
2150
2151 int btrfs_write_inode(struct inode *inode, int wait)
2152 {
2153 struct btrfs_root *root = BTRFS_I(inode)->root;
2154 struct btrfs_trans_handle *trans;
2155 int ret = 0;
2156
2157 if (root->fs_info->closing > 1)
2158 return 0;
2159
2160 if (wait) {
2161 trans = btrfs_join_transaction(root, 1);
2162 btrfs_set_trans_block_group(trans, inode);
2163 ret = btrfs_commit_transaction(trans, root);
2164 }
2165 return ret;
2166 }
2167
2168 /*
2169 * This is somewhat expensive, updating the tree every time the
2170 * inode changes. But, it is most likely to find the inode in cache.
2171 * FIXME, needs more benchmarking...there are no reasons other than performance
2172 * to keep or drop this code.
2173 */
2174 void btrfs_dirty_inode(struct inode *inode)
2175 {
2176 struct btrfs_root *root = BTRFS_I(inode)->root;
2177 struct btrfs_trans_handle *trans;
2178
2179 trans = btrfs_join_transaction(root, 1);
2180 btrfs_set_trans_block_group(trans, inode);
2181 btrfs_update_inode(trans, root, inode);
2182 btrfs_end_transaction(trans, root);
2183 }
2184
2185 static int btrfs_set_inode_index_count(struct inode *inode)
2186 {
2187 struct btrfs_root *root = BTRFS_I(inode)->root;
2188 struct btrfs_key key, found_key;
2189 struct btrfs_path *path;
2190 struct extent_buffer *leaf;
2191 int ret;
2192
2193 key.objectid = inode->i_ino;
2194 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
2195 key.offset = (u64)-1;
2196
2197 path = btrfs_alloc_path();
2198 if (!path)
2199 return -ENOMEM;
2200
2201 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2202 if (ret < 0)
2203 goto out;
2204 /* FIXME: we should be able to handle this */
2205 if (ret == 0)
2206 goto out;
2207 ret = 0;
2208
2209 /*
2210 * MAGIC NUMBER EXPLANATION:
2211 * since we search a directory based on f_pos we have to start at 2
2212 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
2213 * else has to start at 2
2214 */
2215 if (path->slots[0] == 0) {
2216 BTRFS_I(inode)->index_cnt = 2;
2217 goto out;
2218 }
2219
2220 path->slots[0]--;
2221
2222 leaf = path->nodes[0];
2223 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2224
2225 if (found_key.objectid != inode->i_ino ||
2226 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
2227 BTRFS_I(inode)->index_cnt = 2;
2228 goto out;
2229 }
2230
2231 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
2232 out:
2233 btrfs_free_path(path);
2234 return ret;
2235 }
2236
2237 static int btrfs_set_inode_index(struct inode *dir, struct inode *inode,
2238 u64 *index)
2239 {
2240 int ret = 0;
2241
2242 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
2243 ret = btrfs_set_inode_index_count(dir);
2244 if (ret) {
2245 return ret;
2246 }
2247 }
2248
2249 *index = BTRFS_I(dir)->index_cnt;
2250 BTRFS_I(dir)->index_cnt++;
2251
2252 return ret;
2253 }
2254
2255 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
2256 struct btrfs_root *root,
2257 struct inode *dir,
2258 const char *name, int name_len,
2259 u64 ref_objectid,
2260 u64 objectid,
2261 struct btrfs_block_group_cache *group,
2262 int mode, u64 *index)
2263 {
2264 struct inode *inode;
2265 struct btrfs_inode_item *inode_item;
2266 struct btrfs_block_group_cache *new_inode_group;
2267 struct btrfs_key *location;
2268 struct btrfs_path *path;
2269 struct btrfs_inode_ref *ref;
2270 struct btrfs_key key[2];
2271 u32 sizes[2];
2272 unsigned long ptr;
2273 int ret;
2274 int owner;
2275
2276 path = btrfs_alloc_path();
2277 BUG_ON(!path);
2278
2279 inode = new_inode(root->fs_info->sb);
2280 if (!inode)
2281 return ERR_PTR(-ENOMEM);
2282
2283 if (dir) {
2284 ret = btrfs_set_inode_index(dir, inode, index);
2285 if (ret)
2286 return ERR_PTR(ret);
2287 }
2288 /*
2289 * index_cnt is ignored for everything but a dir,
2290 * btrfs_get_inode_index_count has an explanation for the magic
2291 * number
2292 */
2293 init_btrfs_i(inode);
2294 BTRFS_I(inode)->index_cnt = 2;
2295 BTRFS_I(inode)->root = root;
2296 BTRFS_I(inode)->generation = trans->transid;
2297
2298 if (mode & S_IFDIR)
2299 owner = 0;
2300 else
2301 owner = 1;
2302 new_inode_group = btrfs_find_block_group(root, group, 0,
2303 BTRFS_BLOCK_GROUP_METADATA, owner);
2304 if (!new_inode_group) {
2305 printk("find_block group failed\n");
2306 new_inode_group = group;
2307 }
2308 BTRFS_I(inode)->block_group = new_inode_group;
2309
2310 key[0].objectid = objectid;
2311 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
2312 key[0].offset = 0;
2313
2314 key[1].objectid = objectid;
2315 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
2316 key[1].offset = ref_objectid;
2317
2318 sizes[0] = sizeof(struct btrfs_inode_item);
2319 sizes[1] = name_len + sizeof(*ref);
2320
2321 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
2322 if (ret != 0)
2323 goto fail;
2324
2325 if (objectid > root->highest_inode)
2326 root->highest_inode = objectid;
2327
2328 inode->i_uid = current->fsuid;
2329 inode->i_gid = current->fsgid;
2330 inode->i_mode = mode;
2331 inode->i_ino = objectid;
2332 inode->i_blocks = 0;
2333 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
2334 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2335 struct btrfs_inode_item);
2336 fill_inode_item(trans, path->nodes[0], inode_item, inode);
2337
2338 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
2339 struct btrfs_inode_ref);
2340 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
2341 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
2342 ptr = (unsigned long)(ref + 1);
2343 write_extent_buffer(path->nodes[0], name, ptr, name_len);
2344
2345 btrfs_mark_buffer_dirty(path->nodes[0]);
2346 btrfs_free_path(path);
2347
2348 location = &BTRFS_I(inode)->location;
2349 location->objectid = objectid;
2350 location->offset = 0;
2351 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
2352
2353 insert_inode_hash(inode);
2354 return inode;
2355 fail:
2356 if (dir)
2357 BTRFS_I(dir)->index_cnt--;
2358 btrfs_free_path(path);
2359 return ERR_PTR(ret);
2360 }
2361
2362 static inline u8 btrfs_inode_type(struct inode *inode)
2363 {
2364 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
2365 }
2366
2367 int btrfs_add_link(struct btrfs_trans_handle *trans,
2368 struct inode *parent_inode, struct inode *inode,
2369 const char *name, int name_len, int add_backref, u64 index)
2370 {
2371 int ret;
2372 struct btrfs_key key;
2373 struct btrfs_root *root = BTRFS_I(parent_inode)->root;
2374
2375 key.objectid = inode->i_ino;
2376 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
2377 key.offset = 0;
2378
2379 ret = btrfs_insert_dir_item(trans, root, name, name_len,
2380 parent_inode->i_ino,
2381 &key, btrfs_inode_type(inode),
2382 index);
2383 if (ret == 0) {
2384 if (add_backref) {
2385 ret = btrfs_insert_inode_ref(trans, root,
2386 name, name_len,
2387 inode->i_ino,
2388 parent_inode->i_ino,
2389 index);
2390 }
2391 btrfs_i_size_write(parent_inode, parent_inode->i_size +
2392 name_len * 2);
2393 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
2394 ret = btrfs_update_inode(trans, root, parent_inode);
2395 }
2396 return ret;
2397 }
2398
2399 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
2400 struct dentry *dentry, struct inode *inode,
2401 int backref, u64 index)
2402 {
2403 int err = btrfs_add_link(trans, dentry->d_parent->d_inode,
2404 inode, dentry->d_name.name,
2405 dentry->d_name.len, backref, index);
2406 if (!err) {
2407 d_instantiate(dentry, inode);
2408 return 0;
2409 }
2410 if (err > 0)
2411 err = -EEXIST;
2412 return err;
2413 }
2414
2415 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
2416 int mode, dev_t rdev)
2417 {
2418 struct btrfs_trans_handle *trans;
2419 struct btrfs_root *root = BTRFS_I(dir)->root;
2420 struct inode *inode = NULL;
2421 int err;
2422 int drop_inode = 0;
2423 u64 objectid;
2424 unsigned long nr = 0;
2425 u64 index = 0;
2426
2427 if (!new_valid_dev(rdev))
2428 return -EINVAL;
2429
2430 err = btrfs_check_free_space(root, 1, 0);
2431 if (err)
2432 goto fail;
2433
2434 trans = btrfs_start_transaction(root, 1);
2435 btrfs_set_trans_block_group(trans, dir);
2436
2437 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2438 if (err) {
2439 err = -ENOSPC;
2440 goto out_unlock;
2441 }
2442
2443 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
2444 dentry->d_name.len,
2445 dentry->d_parent->d_inode->i_ino, objectid,
2446 BTRFS_I(dir)->block_group, mode, &index);
2447 err = PTR_ERR(inode);
2448 if (IS_ERR(inode))
2449 goto out_unlock;
2450
2451 err = btrfs_init_acl(inode, dir);
2452 if (err) {
2453 drop_inode = 1;
2454 goto out_unlock;
2455 }
2456
2457 btrfs_set_trans_block_group(trans, inode);
2458 err = btrfs_add_nondir(trans, dentry, inode, 0, index);
2459 if (err)
2460 drop_inode = 1;
2461 else {
2462 inode->i_op = &btrfs_special_inode_operations;
2463 init_special_inode(inode, inode->i_mode, rdev);
2464 btrfs_update_inode(trans, root, inode);
2465 }
2466 dir->i_sb->s_dirt = 1;
2467 btrfs_update_inode_block_group(trans, inode);
2468 btrfs_update_inode_block_group(trans, dir);
2469 out_unlock:
2470 nr = trans->blocks_used;
2471 btrfs_end_transaction_throttle(trans, root);
2472 fail:
2473 if (drop_inode) {
2474 inode_dec_link_count(inode);
2475 iput(inode);
2476 }
2477 btrfs_btree_balance_dirty(root, nr);
2478 return err;
2479 }
2480
2481 static int btrfs_create(struct inode *dir, struct dentry *dentry,
2482 int mode, struct nameidata *nd)
2483 {
2484 struct btrfs_trans_handle *trans;
2485 struct btrfs_root *root = BTRFS_I(dir)->root;
2486 struct inode *inode = NULL;
2487 int err;
2488 int drop_inode = 0;
2489 unsigned long nr = 0;
2490 u64 objectid;
2491 u64 index = 0;
2492
2493 err = btrfs_check_free_space(root, 1, 0);
2494 if (err)
2495 goto fail;
2496 trans = btrfs_start_transaction(root, 1);
2497 btrfs_set_trans_block_group(trans, dir);
2498
2499 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2500 if (err) {
2501 err = -ENOSPC;
2502 goto out_unlock;
2503 }
2504
2505 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
2506 dentry->d_name.len,
2507 dentry->d_parent->d_inode->i_ino,
2508 objectid, BTRFS_I(dir)->block_group, mode,
2509 &index);
2510 err = PTR_ERR(inode);
2511 if (IS_ERR(inode))
2512 goto out_unlock;
2513
2514 err = btrfs_init_acl(inode, dir);
2515 if (err) {
2516 drop_inode = 1;
2517 goto out_unlock;
2518 }
2519
2520 btrfs_set_trans_block_group(trans, inode);
2521 err = btrfs_add_nondir(trans, dentry, inode, 0, index);
2522 if (err)
2523 drop_inode = 1;
2524 else {
2525 inode->i_mapping->a_ops = &btrfs_aops;
2526 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2527 inode->i_fop = &btrfs_file_operations;
2528 inode->i_op = &btrfs_file_inode_operations;
2529 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
2530 }
2531 dir->i_sb->s_dirt = 1;
2532 btrfs_update_inode_block_group(trans, inode);
2533 btrfs_update_inode_block_group(trans, dir);
2534 out_unlock:
2535 nr = trans->blocks_used;
2536 btrfs_end_transaction_throttle(trans, root);
2537 fail:
2538 if (drop_inode) {
2539 inode_dec_link_count(inode);
2540 iput(inode);
2541 }
2542 btrfs_btree_balance_dirty(root, nr);
2543 return err;
2544 }
2545
2546 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
2547 struct dentry *dentry)
2548 {
2549 struct btrfs_trans_handle *trans;
2550 struct btrfs_root *root = BTRFS_I(dir)->root;
2551 struct inode *inode = old_dentry->d_inode;
2552 u64 index;
2553 unsigned long nr = 0;
2554 int err;
2555 int drop_inode = 0;
2556
2557 if (inode->i_nlink == 0)
2558 return -ENOENT;
2559
2560 btrfs_inc_nlink(inode);
2561 err = btrfs_check_free_space(root, 1, 0);
2562 if (err)
2563 goto fail;
2564 err = btrfs_set_inode_index(dir, inode, &index);
2565 if (err)
2566 goto fail;
2567
2568 trans = btrfs_start_transaction(root, 1);
2569
2570 btrfs_set_trans_block_group(trans, dir);
2571 atomic_inc(&inode->i_count);
2572
2573 err = btrfs_add_nondir(trans, dentry, inode, 1, index);
2574
2575 if (err)
2576 drop_inode = 1;
2577
2578 dir->i_sb->s_dirt = 1;
2579 btrfs_update_inode_block_group(trans, dir);
2580 err = btrfs_update_inode(trans, root, inode);
2581
2582 if (err)
2583 drop_inode = 1;
2584
2585 nr = trans->blocks_used;
2586 btrfs_end_transaction_throttle(trans, root);
2587 fail:
2588 if (drop_inode) {
2589 inode_dec_link_count(inode);
2590 iput(inode);
2591 }
2592 btrfs_btree_balance_dirty(root, nr);
2593 return err;
2594 }
2595
2596 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
2597 {
2598 struct inode *inode = NULL;
2599 struct btrfs_trans_handle *trans;
2600 struct btrfs_root *root = BTRFS_I(dir)->root;
2601 int err = 0;
2602 int drop_on_err = 0;
2603 u64 objectid = 0;
2604 u64 index = 0;
2605 unsigned long nr = 1;
2606
2607 err = btrfs_check_free_space(root, 1, 0);
2608 if (err)
2609 goto out_unlock;
2610
2611 trans = btrfs_start_transaction(root, 1);
2612 btrfs_set_trans_block_group(trans, dir);
2613
2614 if (IS_ERR(trans)) {
2615 err = PTR_ERR(trans);
2616 goto out_unlock;
2617 }
2618
2619 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2620 if (err) {
2621 err = -ENOSPC;
2622 goto out_unlock;
2623 }
2624
2625 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
2626 dentry->d_name.len,
2627 dentry->d_parent->d_inode->i_ino, objectid,
2628 BTRFS_I(dir)->block_group, S_IFDIR | mode,
2629 &index);
2630 if (IS_ERR(inode)) {
2631 err = PTR_ERR(inode);
2632 goto out_fail;
2633 }
2634
2635 drop_on_err = 1;
2636
2637 err = btrfs_init_acl(inode, dir);
2638 if (err)
2639 goto out_fail;
2640
2641 inode->i_op = &btrfs_dir_inode_operations;
2642 inode->i_fop = &btrfs_dir_file_operations;
2643 btrfs_set_trans_block_group(trans, inode);
2644
2645 btrfs_i_size_write(inode, 0);
2646 err = btrfs_update_inode(trans, root, inode);
2647 if (err)
2648 goto out_fail;
2649
2650 err = btrfs_add_link(trans, dentry->d_parent->d_inode,
2651 inode, dentry->d_name.name,
2652 dentry->d_name.len, 0, index);
2653 if (err)
2654 goto out_fail;
2655
2656 d_instantiate(dentry, inode);
2657 drop_on_err = 0;
2658 dir->i_sb->s_dirt = 1;
2659 btrfs_update_inode_block_group(trans, inode);
2660 btrfs_update_inode_block_group(trans, dir);
2661
2662 out_fail:
2663 nr = trans->blocks_used;
2664 btrfs_end_transaction_throttle(trans, root);
2665
2666 out_unlock:
2667 if (drop_on_err)
2668 iput(inode);
2669 btrfs_btree_balance_dirty(root, nr);
2670 return err;
2671 }
2672
2673 static int merge_extent_mapping(struct extent_map_tree *em_tree,
2674 struct extent_map *existing,
2675 struct extent_map *em,
2676 u64 map_start, u64 map_len)
2677 {
2678 u64 start_diff;
2679
2680 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
2681 start_diff = map_start - em->start;
2682 em->start = map_start;
2683 em->len = map_len;
2684 if (em->block_start < EXTENT_MAP_LAST_BYTE)
2685 em->block_start += start_diff;
2686 return add_extent_mapping(em_tree, em);
2687 }
2688
2689 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
2690 size_t pg_offset, u64 start, u64 len,
2691 int create)
2692 {
2693 int ret;
2694 int err = 0;
2695 u64 bytenr;
2696 u64 extent_start = 0;
2697 u64 extent_end = 0;
2698 u64 objectid = inode->i_ino;
2699 u32 found_type;
2700 struct btrfs_path *path = NULL;
2701 struct btrfs_root *root = BTRFS_I(inode)->root;
2702 struct btrfs_file_extent_item *item;
2703 struct extent_buffer *leaf;
2704 struct btrfs_key found_key;
2705 struct extent_map *em = NULL;
2706 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
2707 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2708 struct btrfs_trans_handle *trans = NULL;
2709
2710 again:
2711 spin_lock(&em_tree->lock);
2712 em = lookup_extent_mapping(em_tree, start, len);
2713 if (em)
2714 em->bdev = root->fs_info->fs_devices->latest_bdev;
2715 spin_unlock(&em_tree->lock);
2716
2717 if (em) {
2718 if (em->start > start || em->start + em->len <= start)
2719 free_extent_map(em);
2720 else if (em->block_start == EXTENT_MAP_INLINE && page)
2721 free_extent_map(em);
2722 else
2723 goto out;
2724 }
2725 em = alloc_extent_map(GFP_NOFS);
2726 if (!em) {
2727 err = -ENOMEM;
2728 goto out;
2729 }
2730 em->bdev = root->fs_info->fs_devices->latest_bdev;
2731 em->start = EXTENT_MAP_HOLE;
2732 em->len = (u64)-1;
2733
2734 if (!path) {
2735 path = btrfs_alloc_path();
2736 BUG_ON(!path);
2737 }
2738
2739 ret = btrfs_lookup_file_extent(trans, root, path,
2740 objectid, start, trans != NULL);
2741 if (ret < 0) {
2742 err = ret;
2743 goto out;
2744 }
2745
2746 if (ret != 0) {
2747 if (path->slots[0] == 0)
2748 goto not_found;
2749 path->slots[0]--;
2750 }
2751
2752 leaf = path->nodes[0];
2753 item = btrfs_item_ptr(leaf, path->slots[0],
2754 struct btrfs_file_extent_item);
2755 /* are we inside the extent that was found? */
2756 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2757 found_type = btrfs_key_type(&found_key);
2758 if (found_key.objectid != objectid ||
2759 found_type != BTRFS_EXTENT_DATA_KEY) {
2760 goto not_found;
2761 }
2762
2763 found_type = btrfs_file_extent_type(leaf, item);
2764 extent_start = found_key.offset;
2765 if (found_type == BTRFS_FILE_EXTENT_REG) {
2766 extent_end = extent_start +
2767 btrfs_file_extent_num_bytes(leaf, item);
2768 err = 0;
2769 if (start < extent_start || start >= extent_end) {
2770 em->start = start;
2771 if (start < extent_start) {
2772 if (start + len <= extent_start)
2773 goto not_found;
2774 em->len = extent_end - extent_start;
2775 } else {
2776 em->len = len;
2777 }
2778 goto not_found_em;
2779 }
2780 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
2781 if (bytenr == 0) {
2782 em->start = extent_start;
2783 em->len = extent_end - extent_start;
2784 em->block_start = EXTENT_MAP_HOLE;
2785 goto insert;
2786 }
2787 bytenr += btrfs_file_extent_offset(leaf, item);
2788 em->block_start = bytenr;
2789 em->start = extent_start;
2790 em->len = extent_end - extent_start;
2791 goto insert;
2792 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
2793 u64 page_start;
2794 unsigned long ptr;
2795 char *map;
2796 size_t size;
2797 size_t extent_offset;
2798 size_t copy_size;
2799
2800 size = btrfs_file_extent_inline_len(leaf, btrfs_item_nr(leaf,
2801 path->slots[0]));
2802 extent_end = (extent_start + size + root->sectorsize - 1) &
2803 ~((u64)root->sectorsize - 1);
2804 if (start < extent_start || start >= extent_end) {
2805 em->start = start;
2806 if (start < extent_start) {
2807 if (start + len <= extent_start)
2808 goto not_found;
2809 em->len = extent_end - extent_start;
2810 } else {
2811 em->len = len;
2812 }
2813 goto not_found_em;
2814 }
2815 em->block_start = EXTENT_MAP_INLINE;
2816
2817 if (!page) {
2818 em->start = extent_start;
2819 em->len = size;
2820 goto out;
2821 }
2822
2823 page_start = page_offset(page) + pg_offset;
2824 extent_offset = page_start - extent_start;
2825 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
2826 size - extent_offset);
2827 em->start = extent_start + extent_offset;
2828 em->len = (copy_size + root->sectorsize - 1) &
2829 ~((u64)root->sectorsize - 1);
2830 map = kmap(page);
2831 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
2832 if (create == 0 && !PageUptodate(page)) {
2833 read_extent_buffer(leaf, map + pg_offset, ptr,
2834 copy_size);
2835 flush_dcache_page(page);
2836 } else if (create && PageUptodate(page)) {
2837 if (!trans) {
2838 kunmap(page);
2839 free_extent_map(em);
2840 em = NULL;
2841 btrfs_release_path(root, path);
2842 trans = btrfs_join_transaction(root, 1);
2843 goto again;
2844 }
2845 write_extent_buffer(leaf, map + pg_offset, ptr,
2846 copy_size);
2847 btrfs_mark_buffer_dirty(leaf);
2848 }
2849 kunmap(page);
2850 set_extent_uptodate(io_tree, em->start,
2851 extent_map_end(em) - 1, GFP_NOFS);
2852 goto insert;
2853 } else {
2854 printk("unkknown found_type %d\n", found_type);
2855 WARN_ON(1);
2856 }
2857 not_found:
2858 em->start = start;
2859 em->len = len;
2860 not_found_em:
2861 em->block_start = EXTENT_MAP_HOLE;
2862 insert:
2863 btrfs_release_path(root, path);
2864 if (em->start > start || extent_map_end(em) <= start) {
2865 printk("bad extent! em: [%Lu %Lu] passed [%Lu %Lu]\n", em->start, em->len, start, len);
2866 err = -EIO;
2867 goto out;
2868 }
2869
2870 err = 0;
2871 spin_lock(&em_tree->lock);
2872 ret = add_extent_mapping(em_tree, em);
2873 /* it is possible that someone inserted the extent into the tree
2874 * while we had the lock dropped. It is also possible that
2875 * an overlapping map exists in the tree
2876 */
2877 if (ret == -EEXIST) {
2878 struct extent_map *existing;
2879
2880 ret = 0;
2881
2882 existing = lookup_extent_mapping(em_tree, start, len);
2883 if (existing && (existing->start > start ||
2884 existing->start + existing->len <= start)) {
2885 free_extent_map(existing);
2886 existing = NULL;
2887 }
2888 if (!existing) {
2889 existing = lookup_extent_mapping(em_tree, em->start,
2890 em->len);
2891 if (existing) {
2892 err = merge_extent_mapping(em_tree, existing,
2893 em, start,
2894 root->sectorsize);
2895 free_extent_map(existing);
2896 if (err) {
2897 free_extent_map(em);
2898 em = NULL;
2899 }
2900 } else {
2901 err = -EIO;
2902 printk("failing to insert %Lu %Lu\n",
2903 start, len);
2904 free_extent_map(em);
2905 em = NULL;
2906 }
2907 } else {
2908 free_extent_map(em);
2909 em = existing;
2910 err = 0;
2911 }
2912 }
2913 spin_unlock(&em_tree->lock);
2914 out:
2915 if (path)
2916 btrfs_free_path(path);
2917 if (trans) {
2918 ret = btrfs_end_transaction(trans, root);
2919 if (!err) {
2920 err = ret;
2921 }
2922 }
2923 if (err) {
2924 free_extent_map(em);
2925 WARN_ON(1);
2926 return ERR_PTR(err);
2927 }
2928 return em;
2929 }
2930
2931 #if 0 /* waiting for O_DIRECT reads */
2932 static int btrfs_get_block(struct inode *inode, sector_t iblock,
2933 struct buffer_head *bh_result, int create)
2934 {
2935 struct extent_map *em;
2936 u64 start = (u64)iblock << inode->i_blkbits;
2937 struct btrfs_multi_bio *multi = NULL;
2938 struct btrfs_root *root = BTRFS_I(inode)->root;
2939 u64 len;
2940 u64 logical;
2941 u64 map_length;
2942 int ret = 0;
2943
2944 em = btrfs_get_extent(inode, NULL, 0, start, bh_result->b_size, 0);
2945
2946 if (!em || IS_ERR(em))
2947 goto out;
2948
2949 if (em->start > start || em->start + em->len <= start) {
2950 goto out;
2951 }
2952
2953 if (em->block_start == EXTENT_MAP_INLINE) {
2954 ret = -EINVAL;
2955 goto out;
2956 }
2957
2958 len = em->start + em->len - start;
2959 len = min_t(u64, len, INT_LIMIT(typeof(bh_result->b_size)));
2960
2961 if (em->block_start == EXTENT_MAP_HOLE ||
2962 em->block_start == EXTENT_MAP_DELALLOC) {
2963 bh_result->b_size = len;
2964 goto out;
2965 }
2966
2967 logical = start - em->start;
2968 logical = em->block_start + logical;
2969
2970 map_length = len;
2971 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
2972 logical, &map_length, &multi, 0);
2973 BUG_ON(ret);
2974 bh_result->b_blocknr = multi->stripes[0].physical >> inode->i_blkbits;
2975 bh_result->b_size = min(map_length, len);
2976
2977 bh_result->b_bdev = multi->stripes[0].dev->bdev;
2978 set_buffer_mapped(bh_result);
2979 kfree(multi);
2980 out:
2981 free_extent_map(em);
2982 return ret;
2983 }
2984 #endif
2985
2986 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
2987 const struct iovec *iov, loff_t offset,
2988 unsigned long nr_segs)
2989 {
2990 return -EINVAL;
2991 #if 0
2992 struct file *file = iocb->ki_filp;
2993 struct inode *inode = file->f_mapping->host;
2994
2995 if (rw == WRITE)
2996 return -EINVAL;
2997
2998 return blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
2999 offset, nr_segs, btrfs_get_block, NULL);
3000 #endif
3001 }
3002
3003 static sector_t btrfs_bmap(struct address_space *mapping, sector_t iblock)
3004 {
3005 return extent_bmap(mapping, iblock, btrfs_get_extent);
3006 }
3007
3008 int btrfs_readpage(struct file *file, struct page *page)
3009 {
3010 struct extent_io_tree *tree;
3011 tree = &BTRFS_I(page->mapping->host)->io_tree;
3012 return extent_read_full_page(tree, page, btrfs_get_extent);
3013 }
3014
3015 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
3016 {
3017 struct extent_io_tree *tree;
3018
3019
3020 if (current->flags & PF_MEMALLOC) {
3021 redirty_page_for_writepage(wbc, page);
3022 unlock_page(page);
3023 return 0;
3024 }
3025 tree = &BTRFS_I(page->mapping->host)->io_tree;
3026 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
3027 }
3028
3029 int btrfs_writepages(struct address_space *mapping,
3030 struct writeback_control *wbc)
3031 {
3032 struct extent_io_tree *tree;
3033 tree = &BTRFS_I(mapping->host)->io_tree;
3034 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
3035 }
3036
3037 static int
3038 btrfs_readpages(struct file *file, struct address_space *mapping,
3039 struct list_head *pages, unsigned nr_pages)
3040 {
3041 struct extent_io_tree *tree;
3042 tree = &BTRFS_I(mapping->host)->io_tree;
3043 return extent_readpages(tree, mapping, pages, nr_pages,
3044 btrfs_get_extent);
3045 }
3046 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
3047 {
3048 struct extent_io_tree *tree;
3049 struct extent_map_tree *map;
3050 int ret;
3051
3052 tree = &BTRFS_I(page->mapping->host)->io_tree;
3053 map = &BTRFS_I(page->mapping->host)->extent_tree;
3054 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
3055 if (ret == 1) {
3056 ClearPagePrivate(page);
3057 set_page_private(page, 0);
3058 page_cache_release(page);
3059 }
3060 return ret;
3061 }
3062
3063 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
3064 {
3065 if (PageWriteback(page) || PageDirty(page))
3066 return 0;
3067 return __btrfs_releasepage(page, gfp_flags);
3068 }
3069
3070 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
3071 {
3072 struct extent_io_tree *tree;
3073 struct btrfs_ordered_extent *ordered;
3074 u64 page_start = page_offset(page);
3075 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
3076
3077 wait_on_page_writeback(page);
3078 tree = &BTRFS_I(page->mapping->host)->io_tree;
3079 if (offset) {
3080 btrfs_releasepage(page, GFP_NOFS);
3081 return;
3082 }
3083
3084 lock_extent(tree, page_start, page_end, GFP_NOFS);
3085 ordered = btrfs_lookup_ordered_extent(page->mapping->host,
3086 page_offset(page));
3087 if (ordered) {
3088 /*
3089 * IO on this page will never be started, so we need
3090 * to account for any ordered extents now
3091 */
3092 clear_extent_bit(tree, page_start, page_end,
3093 EXTENT_DIRTY | EXTENT_DELALLOC |
3094 EXTENT_LOCKED, 1, 0, GFP_NOFS);
3095 btrfs_finish_ordered_io(page->mapping->host,
3096 page_start, page_end);
3097 btrfs_put_ordered_extent(ordered);
3098 lock_extent(tree, page_start, page_end, GFP_NOFS);
3099 }
3100 clear_extent_bit(tree, page_start, page_end,
3101 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
3102 EXTENT_ORDERED,
3103 1, 1, GFP_NOFS);
3104 __btrfs_releasepage(page, GFP_NOFS);
3105
3106 ClearPageChecked(page);
3107 if (PagePrivate(page)) {
3108 ClearPagePrivate(page);
3109 set_page_private(page, 0);
3110 page_cache_release(page);
3111 }
3112 }
3113
3114 /*
3115 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
3116 * called from a page fault handler when a page is first dirtied. Hence we must
3117 * be careful to check for EOF conditions here. We set the page up correctly
3118 * for a written page which means we get ENOSPC checking when writing into
3119 * holes and correct delalloc and unwritten extent mapping on filesystems that
3120 * support these features.
3121 *
3122 * We are not allowed to take the i_mutex here so we have to play games to
3123 * protect against truncate races as the page could now be beyond EOF. Because
3124 * vmtruncate() writes the inode size before removing pages, once we have the
3125 * page lock we can determine safely if the page is beyond EOF. If it is not
3126 * beyond EOF, then the page is guaranteed safe against truncation until we
3127 * unlock the page.
3128 */
3129 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
3130 {
3131 struct inode *inode = fdentry(vma->vm_file)->d_inode;
3132 struct btrfs_root *root = BTRFS_I(inode)->root;
3133 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3134 struct btrfs_ordered_extent *ordered;
3135 char *kaddr;
3136 unsigned long zero_start;
3137 loff_t size;
3138 int ret;
3139 u64 page_start;
3140 u64 page_end;
3141
3142 ret = btrfs_check_free_space(root, PAGE_CACHE_SIZE, 0);
3143 if (ret)
3144 goto out;
3145
3146 ret = -EINVAL;
3147 again:
3148 lock_page(page);
3149 size = i_size_read(inode);
3150 page_start = page_offset(page);
3151 page_end = page_start + PAGE_CACHE_SIZE - 1;
3152
3153 if ((page->mapping != inode->i_mapping) ||
3154 (page_start >= size)) {
3155 /* page got truncated out from underneath us */
3156 goto out_unlock;
3157 }
3158 wait_on_page_writeback(page);
3159
3160 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
3161 set_page_extent_mapped(page);
3162
3163 /*
3164 * we can't set the delalloc bits if there are pending ordered
3165 * extents. Drop our locks and wait for them to finish
3166 */
3167 ordered = btrfs_lookup_ordered_extent(inode, page_start);
3168 if (ordered) {
3169 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
3170 unlock_page(page);
3171 btrfs_start_ordered_extent(inode, ordered, 1);
3172 btrfs_put_ordered_extent(ordered);
3173 goto again;
3174 }
3175
3176 btrfs_set_extent_delalloc(inode, page_start, page_end);
3177 ret = 0;
3178
3179 /* page is wholly or partially inside EOF */
3180 if (page_start + PAGE_CACHE_SIZE > size)
3181 zero_start = size & ~PAGE_CACHE_MASK;
3182 else
3183 zero_start = PAGE_CACHE_SIZE;
3184
3185 if (zero_start != PAGE_CACHE_SIZE) {
3186 kaddr = kmap(page);
3187 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
3188 flush_dcache_page(page);
3189 kunmap(page);
3190 }
3191 ClearPageChecked(page);
3192 set_page_dirty(page);
3193 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
3194
3195 out_unlock:
3196 unlock_page(page);
3197 out:
3198 return ret;
3199 }
3200
3201 static void btrfs_truncate(struct inode *inode)
3202 {
3203 struct btrfs_root *root = BTRFS_I(inode)->root;
3204 int ret;
3205 struct btrfs_trans_handle *trans;
3206 unsigned long nr;
3207 u64 mask = root->sectorsize - 1;
3208
3209 if (!S_ISREG(inode->i_mode))
3210 return;
3211 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
3212 return;
3213
3214 btrfs_truncate_page(inode->i_mapping, inode->i_size);
3215 btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
3216
3217 trans = btrfs_start_transaction(root, 1);
3218 btrfs_set_trans_block_group(trans, inode);
3219 btrfs_i_size_write(inode, inode->i_size);
3220
3221 ret = btrfs_orphan_add(trans, inode);
3222 if (ret)
3223 goto out;
3224 /* FIXME, add redo link to tree so we don't leak on crash */
3225 ret = btrfs_truncate_inode_items(trans, root, inode, inode->i_size,
3226 BTRFS_EXTENT_DATA_KEY);
3227 btrfs_update_inode(trans, root, inode);
3228
3229 ret = btrfs_orphan_del(trans, inode);
3230 BUG_ON(ret);
3231
3232 out:
3233 nr = trans->blocks_used;
3234 ret = btrfs_end_transaction_throttle(trans, root);
3235 BUG_ON(ret);
3236 btrfs_btree_balance_dirty(root, nr);
3237 }
3238
3239 /*
3240 * Invalidate a single dcache entry at the root of the filesystem.
3241 * Needed after creation of snapshot or subvolume.
3242 */
3243 void btrfs_invalidate_dcache_root(struct btrfs_root *root, char *name,
3244 int namelen)
3245 {
3246 struct dentry *alias, *entry;
3247 struct qstr qstr;
3248
3249 alias = d_find_alias(root->fs_info->sb->s_root->d_inode);
3250 if (alias) {
3251 qstr.name = name;
3252 qstr.len = namelen;
3253 /* change me if btrfs ever gets a d_hash operation */
3254 qstr.hash = full_name_hash(qstr.name, qstr.len);
3255 entry = d_lookup(alias, &qstr);
3256 dput(alias);
3257 if (entry) {
3258 d_invalidate(entry);
3259 dput(entry);
3260 }
3261 }
3262 }
3263
3264 int btrfs_create_subvol_root(struct btrfs_root *new_root,
3265 struct btrfs_trans_handle *trans, u64 new_dirid,
3266 struct btrfs_block_group_cache *block_group)
3267 {
3268 struct inode *inode;
3269 u64 index = 0;
3270
3271 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid,
3272 new_dirid, block_group, S_IFDIR | 0700, &index);
3273 if (IS_ERR(inode))
3274 return PTR_ERR(inode);
3275 inode->i_op = &btrfs_dir_inode_operations;
3276 inode->i_fop = &btrfs_dir_file_operations;
3277 new_root->inode = inode;
3278
3279 inode->i_nlink = 1;
3280 btrfs_i_size_write(inode, 0);
3281
3282 return btrfs_update_inode(trans, new_root, inode);
3283 }
3284
3285 unsigned long btrfs_force_ra(struct address_space *mapping,
3286 struct file_ra_state *ra, struct file *file,
3287 pgoff_t offset, pgoff_t last_index)
3288 {
3289 pgoff_t req_size = last_index - offset + 1;
3290
3291 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
3292 offset = page_cache_readahead(mapping, ra, file, offset, req_size);
3293 return offset;
3294 #else
3295 page_cache_sync_readahead(mapping, ra, file, offset, req_size);
3296 return offset + req_size;
3297 #endif
3298 }
3299
3300 struct inode *btrfs_alloc_inode(struct super_block *sb)
3301 {
3302 struct btrfs_inode *ei;
3303
3304 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
3305 if (!ei)
3306 return NULL;
3307 ei->last_trans = 0;
3308 ei->logged_trans = 0;
3309 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
3310 ei->i_acl = BTRFS_ACL_NOT_CACHED;
3311 ei->i_default_acl = BTRFS_ACL_NOT_CACHED;
3312 INIT_LIST_HEAD(&ei->i_orphan);
3313 return &ei->vfs_inode;
3314 }
3315
3316 void btrfs_destroy_inode(struct inode *inode)
3317 {
3318 struct btrfs_ordered_extent *ordered;
3319 WARN_ON(!list_empty(&inode->i_dentry));
3320 WARN_ON(inode->i_data.nrpages);
3321
3322 if (BTRFS_I(inode)->i_acl &&
3323 BTRFS_I(inode)->i_acl != BTRFS_ACL_NOT_CACHED)
3324 posix_acl_release(BTRFS_I(inode)->i_acl);
3325 if (BTRFS_I(inode)->i_default_acl &&
3326 BTRFS_I(inode)->i_default_acl != BTRFS_ACL_NOT_CACHED)
3327 posix_acl_release(BTRFS_I(inode)->i_default_acl);
3328
3329 spin_lock(&BTRFS_I(inode)->root->list_lock);
3330 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
3331 printk(KERN_ERR "BTRFS: inode %lu: inode still on the orphan"
3332 " list\n", inode->i_ino);
3333 dump_stack();
3334 }
3335 spin_unlock(&BTRFS_I(inode)->root->list_lock);
3336
3337 while(1) {
3338 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
3339 if (!ordered)
3340 break;
3341 else {
3342 printk("found ordered extent %Lu %Lu\n",
3343 ordered->file_offset, ordered->len);
3344 btrfs_remove_ordered_extent(inode, ordered);
3345 btrfs_put_ordered_extent(ordered);
3346 btrfs_put_ordered_extent(ordered);
3347 }
3348 }
3349 btrfs_drop_extent_cache(inode, 0, (u64)-1);
3350 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
3351 }
3352
3353 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
3354 static void init_once(void *foo)
3355 #elif LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
3356 static void init_once(struct kmem_cache * cachep, void *foo)
3357 #else
3358 static void init_once(void * foo, struct kmem_cache * cachep,
3359 unsigned long flags)
3360 #endif
3361 {
3362 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
3363
3364 inode_init_once(&ei->vfs_inode);
3365 }
3366
3367 void btrfs_destroy_cachep(void)
3368 {
3369 if (btrfs_inode_cachep)
3370 kmem_cache_destroy(btrfs_inode_cachep);
3371 if (btrfs_trans_handle_cachep)
3372 kmem_cache_destroy(btrfs_trans_handle_cachep);
3373 if (btrfs_transaction_cachep)
3374 kmem_cache_destroy(btrfs_transaction_cachep);
3375 if (btrfs_bit_radix_cachep)
3376 kmem_cache_destroy(btrfs_bit_radix_cachep);
3377 if (btrfs_path_cachep)
3378 kmem_cache_destroy(btrfs_path_cachep);
3379 }
3380
3381 struct kmem_cache *btrfs_cache_create(const char *name, size_t size,
3382 unsigned long extra_flags,
3383 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
3384 void (*ctor)(void *)
3385 #elif LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
3386 void (*ctor)(struct kmem_cache *, void *)
3387 #else
3388 void (*ctor)(void *, struct kmem_cache *,
3389 unsigned long)
3390 #endif
3391 )
3392 {
3393 return kmem_cache_create(name, size, 0, (SLAB_RECLAIM_ACCOUNT |
3394 SLAB_MEM_SPREAD | extra_flags), ctor
3395 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
3396 ,NULL
3397 #endif
3398 );
3399 }
3400
3401 int btrfs_init_cachep(void)
3402 {
3403 btrfs_inode_cachep = btrfs_cache_create("btrfs_inode_cache",
3404 sizeof(struct btrfs_inode),
3405 0, init_once);
3406 if (!btrfs_inode_cachep)
3407 goto fail;
3408 btrfs_trans_handle_cachep =
3409 btrfs_cache_create("btrfs_trans_handle_cache",
3410 sizeof(struct btrfs_trans_handle),
3411 0, NULL);
3412 if (!btrfs_trans_handle_cachep)
3413 goto fail;
3414 btrfs_transaction_cachep = btrfs_cache_create("btrfs_transaction_cache",
3415 sizeof(struct btrfs_transaction),
3416 0, NULL);
3417 if (!btrfs_transaction_cachep)
3418 goto fail;
3419 btrfs_path_cachep = btrfs_cache_create("btrfs_path_cache",
3420 sizeof(struct btrfs_path),
3421 0, NULL);
3422 if (!btrfs_path_cachep)
3423 goto fail;
3424 btrfs_bit_radix_cachep = btrfs_cache_create("btrfs_radix", 256,
3425 SLAB_DESTROY_BY_RCU, NULL);
3426 if (!btrfs_bit_radix_cachep)
3427 goto fail;
3428 return 0;
3429 fail:
3430 btrfs_destroy_cachep();
3431 return -ENOMEM;
3432 }
3433
3434 static int btrfs_getattr(struct vfsmount *mnt,
3435 struct dentry *dentry, struct kstat *stat)
3436 {
3437 struct inode *inode = dentry->d_inode;
3438 generic_fillattr(inode, stat);
3439 stat->blksize = PAGE_CACHE_SIZE;
3440 stat->blocks = inode->i_blocks + (BTRFS_I(inode)->delalloc_bytes >> 9);
3441 return 0;
3442 }
3443
3444 static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
3445 struct inode * new_dir,struct dentry *new_dentry)
3446 {
3447 struct btrfs_trans_handle *trans;
3448 struct btrfs_root *root = BTRFS_I(old_dir)->root;
3449 struct inode *new_inode = new_dentry->d_inode;
3450 struct inode *old_inode = old_dentry->d_inode;
3451 struct timespec ctime = CURRENT_TIME;
3452 u64 index = 0;
3453 int ret;
3454
3455 if (S_ISDIR(old_inode->i_mode) && new_inode &&
3456 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
3457 return -ENOTEMPTY;
3458 }
3459
3460 ret = btrfs_check_free_space(root, 1, 0);
3461 if (ret)
3462 goto out_unlock;
3463
3464 trans = btrfs_start_transaction(root, 1);
3465
3466 btrfs_set_trans_block_group(trans, new_dir);
3467
3468 btrfs_inc_nlink(old_dentry->d_inode);
3469 old_dir->i_ctime = old_dir->i_mtime = ctime;
3470 new_dir->i_ctime = new_dir->i_mtime = ctime;
3471 old_inode->i_ctime = ctime;
3472
3473 ret = btrfs_unlink_inode(trans, root, old_dir, old_dentry->d_inode,
3474 old_dentry->d_name.name,
3475 old_dentry->d_name.len);
3476 if (ret)
3477 goto out_fail;
3478
3479 if (new_inode) {
3480 new_inode->i_ctime = CURRENT_TIME;
3481 ret = btrfs_unlink_inode(trans, root, new_dir,
3482 new_dentry->d_inode,
3483 new_dentry->d_name.name,
3484 new_dentry->d_name.len);
3485 if (ret)
3486 goto out_fail;
3487 if (new_inode->i_nlink == 0) {
3488 ret = btrfs_orphan_add(trans, new_dentry->d_inode);
3489 if (ret)
3490 goto out_fail;
3491 }
3492
3493 }
3494 ret = btrfs_set_inode_index(new_dir, old_inode, &index);
3495 if (ret)
3496 goto out_fail;
3497
3498 ret = btrfs_add_link(trans, new_dentry->d_parent->d_inode,
3499 old_inode, new_dentry->d_name.name,
3500 new_dentry->d_name.len, 1, index);
3501 if (ret)
3502 goto out_fail;
3503
3504 out_fail:
3505 btrfs_end_transaction_throttle(trans, root);
3506 out_unlock:
3507 return ret;
3508 }
3509
3510 int btrfs_start_delalloc_inodes(struct btrfs_root *root)
3511 {
3512 struct list_head *head = &root->fs_info->delalloc_inodes;
3513 struct btrfs_inode *binode;
3514 unsigned long flags;
3515
3516 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
3517 while(!list_empty(head)) {
3518 binode = list_entry(head->next, struct btrfs_inode,
3519 delalloc_inodes);
3520 atomic_inc(&binode->vfs_inode.i_count);
3521 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
3522 filemap_write_and_wait(binode->vfs_inode.i_mapping);
3523 iput(&binode->vfs_inode);
3524 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
3525 }
3526 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
3527 return 0;
3528 }
3529
3530 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
3531 const char *symname)
3532 {
3533 struct btrfs_trans_handle *trans;
3534 struct btrfs_root *root = BTRFS_I(dir)->root;
3535 struct btrfs_path *path;
3536 struct btrfs_key key;
3537 struct inode *inode = NULL;
3538 int err;
3539 int drop_inode = 0;
3540 u64 objectid;
3541 u64 index = 0 ;
3542 int name_len;
3543 int datasize;
3544 unsigned long ptr;
3545 struct btrfs_file_extent_item *ei;
3546 struct extent_buffer *leaf;
3547 unsigned long nr = 0;
3548
3549 name_len = strlen(symname) + 1;
3550 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
3551 return -ENAMETOOLONG;
3552
3553 err = btrfs_check_free_space(root, 1, 0);
3554 if (err)
3555 goto out_fail;
3556
3557 trans = btrfs_start_transaction(root, 1);
3558 btrfs_set_trans_block_group(trans, dir);
3559
3560 err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
3561 if (err) {
3562 err = -ENOSPC;
3563 goto out_unlock;
3564 }
3565
3566 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
3567 dentry->d_name.len,
3568 dentry->d_parent->d_inode->i_ino, objectid,
3569 BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO,
3570 &index);
3571 err = PTR_ERR(inode);
3572 if (IS_ERR(inode))
3573 goto out_unlock;
3574
3575 err = btrfs_init_acl(inode, dir);
3576 if (err) {
3577 drop_inode = 1;
3578 goto out_unlock;
3579 }
3580
3581 btrfs_set_trans_block_group(trans, inode);
3582 err = btrfs_add_nondir(trans, dentry, inode, 0, index);
3583 if (err)
3584 drop_inode = 1;
3585 else {
3586 inode->i_mapping->a_ops = &btrfs_aops;
3587 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3588 inode->i_fop = &btrfs_file_operations;
3589 inode->i_op = &btrfs_file_inode_operations;
3590 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
3591 }
3592 dir->i_sb->s_dirt = 1;
3593 btrfs_update_inode_block_group(trans, inode);
3594 btrfs_update_inode_block_group(trans, dir);
3595 if (drop_inode)
3596 goto out_unlock;
3597
3598 path = btrfs_alloc_path();
3599 BUG_ON(!path);
3600 key.objectid = inode->i_ino;
3601 key.offset = 0;
3602 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
3603 datasize = btrfs_file_extent_calc_inline_size(name_len);
3604 err = btrfs_insert_empty_item(trans, root, path, &key,
3605 datasize);
3606 if (err) {
3607 drop_inode = 1;
3608 goto out_unlock;
3609 }
3610 leaf = path->nodes[0];
3611 ei = btrfs_item_ptr(leaf, path->slots[0],
3612 struct btrfs_file_extent_item);
3613 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
3614 btrfs_set_file_extent_type(leaf, ei,
3615 BTRFS_FILE_EXTENT_INLINE);
3616 ptr = btrfs_file_extent_inline_start(ei);
3617 write_extent_buffer(leaf, symname, ptr, name_len);
3618 btrfs_mark_buffer_dirty(leaf);
3619 btrfs_free_path(path);
3620
3621 inode->i_op = &btrfs_symlink_inode_operations;
3622 inode->i_mapping->a_ops = &btrfs_symlink_aops;
3623 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3624 btrfs_i_size_write(inode, name_len - 1);
3625 err = btrfs_update_inode(trans, root, inode);
3626 if (err)
3627 drop_inode = 1;
3628
3629 out_unlock:
3630 nr = trans->blocks_used;
3631 btrfs_end_transaction_throttle(trans, root);
3632 out_fail:
3633 if (drop_inode) {
3634 inode_dec_link_count(inode);
3635 iput(inode);
3636 }
3637 btrfs_btree_balance_dirty(root, nr);
3638 return err;
3639 }
3640
3641 static int btrfs_set_page_dirty(struct page *page)
3642 {
3643 return __set_page_dirty_nobuffers(page);
3644 }
3645
3646 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
3647 static int btrfs_permission(struct inode *inode, int mask)
3648 #else
3649 static int btrfs_permission(struct inode *inode, int mask,
3650 struct nameidata *nd)
3651 #endif
3652 {
3653 if (btrfs_test_flag(inode, READONLY) && (mask & MAY_WRITE))
3654 return -EACCES;
3655 return generic_permission(inode, mask, btrfs_check_acl);
3656 }
3657
3658 static struct inode_operations btrfs_dir_inode_operations = {
3659 .lookup = btrfs_lookup,
3660 .create = btrfs_create,
3661 .unlink = btrfs_unlink,
3662 .link = btrfs_link,
3663 .mkdir = btrfs_mkdir,
3664 .rmdir = btrfs_rmdir,
3665 .rename = btrfs_rename,
3666 .symlink = btrfs_symlink,
3667 .setattr = btrfs_setattr,
3668 .mknod = btrfs_mknod,
3669 .setxattr = btrfs_setxattr,
3670 .getxattr = btrfs_getxattr,
3671 .listxattr = btrfs_listxattr,
3672 .removexattr = btrfs_removexattr,
3673 .permission = btrfs_permission,
3674 };
3675 static struct inode_operations btrfs_dir_ro_inode_operations = {
3676 .lookup = btrfs_lookup,
3677 .permission = btrfs_permission,
3678 };
3679 static struct file_operations btrfs_dir_file_operations = {
3680 .llseek = generic_file_llseek,
3681 .read = generic_read_dir,
3682 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,28)
3683 .readdir = btrfs_nfshack_readdir,
3684 #else /* NFSd readdir/lookup deadlock is fixed */
3685 .readdir = btrfs_real_readdir,
3686 #endif
3687 .unlocked_ioctl = btrfs_ioctl,
3688 #ifdef CONFIG_COMPAT
3689 .compat_ioctl = btrfs_ioctl,
3690 #endif
3691 .release = btrfs_release_file,
3692 .fsync = btrfs_sync_file,
3693 };
3694
3695 static struct extent_io_ops btrfs_extent_io_ops = {
3696 .fill_delalloc = run_delalloc_range,
3697 .submit_bio_hook = btrfs_submit_bio_hook,
3698 .merge_bio_hook = btrfs_merge_bio_hook,
3699 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
3700 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
3701 .writepage_start_hook = btrfs_writepage_start_hook,
3702 .readpage_io_failed_hook = btrfs_io_failed_hook,
3703 .set_bit_hook = btrfs_set_bit_hook,
3704 .clear_bit_hook = btrfs_clear_bit_hook,
3705 };
3706
3707 static struct address_space_operations btrfs_aops = {
3708 .readpage = btrfs_readpage,
3709 .writepage = btrfs_writepage,
3710 .writepages = btrfs_writepages,
3711 .readpages = btrfs_readpages,
3712 .sync_page = block_sync_page,
3713 .bmap = btrfs_bmap,
3714 .direct_IO = btrfs_direct_IO,
3715 .invalidatepage = btrfs_invalidatepage,
3716 .releasepage = btrfs_releasepage,
3717 .set_page_dirty = btrfs_set_page_dirty,
3718 };
3719
3720 static struct address_space_operations btrfs_symlink_aops = {
3721 .readpage = btrfs_readpage,
3722 .writepage = btrfs_writepage,
3723 .invalidatepage = btrfs_invalidatepage,
3724 .releasepage = btrfs_releasepage,
3725 };
3726
3727 static struct inode_operations btrfs_file_inode_operations = {
3728 .truncate = btrfs_truncate,
3729 .getattr = btrfs_getattr,
3730 .setattr = btrfs_setattr,
3731 .setxattr = btrfs_setxattr,
3732 .getxattr = btrfs_getxattr,
3733 .listxattr = btrfs_listxattr,
3734 .removexattr = btrfs_removexattr,
3735 .permission = btrfs_permission,
3736 };
3737 static struct inode_operations btrfs_special_inode_operations = {
3738 .getattr = btrfs_getattr,
3739 .setattr = btrfs_setattr,
3740 .permission = btrfs_permission,
3741 .setxattr = btrfs_setxattr,
3742 .getxattr = btrfs_getxattr,
3743 .listxattr = btrfs_listxattr,
3744 .removexattr = btrfs_removexattr,
3745 };
3746 static struct inode_operations btrfs_symlink_inode_operations = {
3747 .readlink = generic_readlink,
3748 .follow_link = page_follow_link_light,
3749 .put_link = page_put_link,
3750 .permission = btrfs_permission,
3751 };
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