2 * Copyright (C) 2007 Oracle. All rights reserved.
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.
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.
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.
19 #include <linux/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.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/backing-dev.h>
30 #include <linux/mpage.h>
31 #include <linux/swap.h>
32 #include <linux/writeback.h>
33 #include <linux/statfs.h>
34 #include <linux/compat.h>
35 #include <linux/bit_spinlock.h>
36 #include <linux/xattr.h>
37 #include <linux/posix_acl.h>
38 #include <linux/falloc.h>
39 #include <linux/slab.h>
40 #include <linux/ratelimit.h>
41 #include <linux/mount.h>
45 #include "transaction.h"
46 #include "btrfs_inode.h"
48 #include "print-tree.h"
49 #include "ordered-data.h"
53 #include "compression.h"
55 #include "free-space-cache.h"
56 #include "inode-map.h"
58 struct btrfs_iget_args {
60 struct btrfs_root *root;
63 static const struct inode_operations btrfs_dir_inode_operations;
64 static const struct inode_operations btrfs_symlink_inode_operations;
65 static const struct inode_operations btrfs_dir_ro_inode_operations;
66 static const struct inode_operations btrfs_special_inode_operations;
67 static const struct inode_operations btrfs_file_inode_operations;
68 static const struct address_space_operations btrfs_aops;
69 static const struct address_space_operations btrfs_symlink_aops;
70 static const struct file_operations btrfs_dir_file_operations;
71 static struct extent_io_ops btrfs_extent_io_ops;
73 static struct kmem_cache *btrfs_inode_cachep;
74 struct kmem_cache *btrfs_trans_handle_cachep;
75 struct kmem_cache *btrfs_transaction_cachep;
76 struct kmem_cache *btrfs_path_cachep;
77 struct kmem_cache *btrfs_free_space_cachep;
80 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
81 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
82 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
83 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
84 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
85 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
86 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
87 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
90 static int btrfs_setsize(struct inode *inode, loff_t newsize);
91 static int btrfs_truncate(struct inode *inode);
92 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end);
93 static noinline int cow_file_range(struct inode *inode,
94 struct page *locked_page,
95 u64 start, u64 end, int *page_started,
96 unsigned long *nr_written, int unlock);
97 static noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
98 struct btrfs_root *root, struct inode *inode);
100 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
101 struct inode *inode, struct inode *dir,
102 const struct qstr *qstr)
106 err = btrfs_init_acl(trans, inode, dir);
108 err = btrfs_xattr_security_init(trans, inode, dir, qstr);
113 * this does all the hard work for inserting an inline extent into
114 * the btree. The caller should have done a btrfs_drop_extents so that
115 * no overlapping inline items exist in the btree
117 static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
118 struct btrfs_root *root, struct inode *inode,
119 u64 start, size_t size, size_t compressed_size,
121 struct page **compressed_pages)
123 struct btrfs_key key;
124 struct btrfs_path *path;
125 struct extent_buffer *leaf;
126 struct page *page = NULL;
129 struct btrfs_file_extent_item *ei;
132 size_t cur_size = size;
134 unsigned long offset;
136 if (compressed_size && compressed_pages)
137 cur_size = compressed_size;
139 path = btrfs_alloc_path();
143 path->leave_spinning = 1;
145 key.objectid = btrfs_ino(inode);
147 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
148 datasize = btrfs_file_extent_calc_inline_size(cur_size);
150 inode_add_bytes(inode, size);
151 ret = btrfs_insert_empty_item(trans, root, path, &key,
158 leaf = path->nodes[0];
159 ei = btrfs_item_ptr(leaf, path->slots[0],
160 struct btrfs_file_extent_item);
161 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
162 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
163 btrfs_set_file_extent_encryption(leaf, ei, 0);
164 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
165 btrfs_set_file_extent_ram_bytes(leaf, ei, size);
166 ptr = btrfs_file_extent_inline_start(ei);
168 if (compress_type != BTRFS_COMPRESS_NONE) {
171 while (compressed_size > 0) {
172 cpage = compressed_pages[i];
173 cur_size = min_t(unsigned long, compressed_size,
176 kaddr = kmap_atomic(cpage, KM_USER0);
177 write_extent_buffer(leaf, kaddr, ptr, cur_size);
178 kunmap_atomic(kaddr, KM_USER0);
182 compressed_size -= cur_size;
184 btrfs_set_file_extent_compression(leaf, ei,
187 page = find_get_page(inode->i_mapping,
188 start >> PAGE_CACHE_SHIFT);
189 btrfs_set_file_extent_compression(leaf, ei, 0);
190 kaddr = kmap_atomic(page, KM_USER0);
191 offset = start & (PAGE_CACHE_SIZE - 1);
192 write_extent_buffer(leaf, kaddr + offset, ptr, size);
193 kunmap_atomic(kaddr, KM_USER0);
194 page_cache_release(page);
196 btrfs_mark_buffer_dirty(leaf);
197 btrfs_free_path(path);
200 * we're an inline extent, so nobody can
201 * extend the file past i_size without locking
202 * a page we already have locked.
204 * We must do any isize and inode updates
205 * before we unlock the pages. Otherwise we
206 * could end up racing with unlink.
208 BTRFS_I(inode)->disk_i_size = inode->i_size;
209 btrfs_update_inode(trans, root, inode);
213 btrfs_free_path(path);
219 * conditionally insert an inline extent into the file. This
220 * does the checks required to make sure the data is small enough
221 * to fit as an inline extent.
223 static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans,
224 struct btrfs_root *root,
225 struct inode *inode, u64 start, u64 end,
226 size_t compressed_size, int compress_type,
227 struct page **compressed_pages)
229 u64 isize = i_size_read(inode);
230 u64 actual_end = min(end + 1, isize);
231 u64 inline_len = actual_end - start;
232 u64 aligned_end = (end + root->sectorsize - 1) &
233 ~((u64)root->sectorsize - 1);
235 u64 data_len = inline_len;
239 data_len = compressed_size;
242 actual_end >= PAGE_CACHE_SIZE ||
243 data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
245 (actual_end & (root->sectorsize - 1)) == 0) ||
247 data_len > root->fs_info->max_inline) {
251 ret = btrfs_drop_extents(trans, inode, start, aligned_end,
255 if (isize > actual_end)
256 inline_len = min_t(u64, isize, actual_end);
257 ret = insert_inline_extent(trans, root, inode, start,
258 inline_len, compressed_size,
259 compress_type, compressed_pages);
261 btrfs_delalloc_release_metadata(inode, end + 1 - start);
262 btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0);
266 struct async_extent {
271 unsigned long nr_pages;
273 struct list_head list;
278 struct btrfs_root *root;
279 struct page *locked_page;
282 struct list_head extents;
283 struct btrfs_work work;
286 static noinline int add_async_extent(struct async_cow *cow,
287 u64 start, u64 ram_size,
290 unsigned long nr_pages,
293 struct async_extent *async_extent;
295 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
296 BUG_ON(!async_extent);
297 async_extent->start = start;
298 async_extent->ram_size = ram_size;
299 async_extent->compressed_size = compressed_size;
300 async_extent->pages = pages;
301 async_extent->nr_pages = nr_pages;
302 async_extent->compress_type = compress_type;
303 list_add_tail(&async_extent->list, &cow->extents);
308 * we create compressed extents in two phases. The first
309 * phase compresses a range of pages that have already been
310 * locked (both pages and state bits are locked).
312 * This is done inside an ordered work queue, and the compression
313 * is spread across many cpus. The actual IO submission is step
314 * two, and the ordered work queue takes care of making sure that
315 * happens in the same order things were put onto the queue by
316 * writepages and friends.
318 * If this code finds it can't get good compression, it puts an
319 * entry onto the work queue to write the uncompressed bytes. This
320 * makes sure that both compressed inodes and uncompressed inodes
321 * are written in the same order that pdflush sent them down.
323 static noinline int compress_file_range(struct inode *inode,
324 struct page *locked_page,
326 struct async_cow *async_cow,
329 struct btrfs_root *root = BTRFS_I(inode)->root;
330 struct btrfs_trans_handle *trans;
332 u64 blocksize = root->sectorsize;
334 u64 isize = i_size_read(inode);
336 struct page **pages = NULL;
337 unsigned long nr_pages;
338 unsigned long nr_pages_ret = 0;
339 unsigned long total_compressed = 0;
340 unsigned long total_in = 0;
341 unsigned long max_compressed = 128 * 1024;
342 unsigned long max_uncompressed = 128 * 1024;
345 int compress_type = root->fs_info->compress_type;
347 /* if this is a small write inside eof, kick off a defragbot */
348 if (end <= BTRFS_I(inode)->disk_i_size && (end - start + 1) < 16 * 1024)
349 btrfs_add_inode_defrag(NULL, inode);
351 actual_end = min_t(u64, isize, end + 1);
354 nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1;
355 nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE);
358 * we don't want to send crud past the end of i_size through
359 * compression, that's just a waste of CPU time. So, if the
360 * end of the file is before the start of our current
361 * requested range of bytes, we bail out to the uncompressed
362 * cleanup code that can deal with all of this.
364 * It isn't really the fastest way to fix things, but this is a
365 * very uncommon corner.
367 if (actual_end <= start)
368 goto cleanup_and_bail_uncompressed;
370 total_compressed = actual_end - start;
372 /* we want to make sure that amount of ram required to uncompress
373 * an extent is reasonable, so we limit the total size in ram
374 * of a compressed extent to 128k. This is a crucial number
375 * because it also controls how easily we can spread reads across
376 * cpus for decompression.
378 * We also want to make sure the amount of IO required to do
379 * a random read is reasonably small, so we limit the size of
380 * a compressed extent to 128k.
382 total_compressed = min(total_compressed, max_uncompressed);
383 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
384 num_bytes = max(blocksize, num_bytes);
389 * we do compression for mount -o compress and when the
390 * inode has not been flagged as nocompress. This flag can
391 * change at any time if we discover bad compression ratios.
393 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) &&
394 (btrfs_test_opt(root, COMPRESS) ||
395 (BTRFS_I(inode)->force_compress) ||
396 (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))) {
398 pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
400 /* just bail out to the uncompressed code */
404 if (BTRFS_I(inode)->force_compress)
405 compress_type = BTRFS_I(inode)->force_compress;
407 ret = btrfs_compress_pages(compress_type,
408 inode->i_mapping, start,
409 total_compressed, pages,
410 nr_pages, &nr_pages_ret,
416 unsigned long offset = total_compressed &
417 (PAGE_CACHE_SIZE - 1);
418 struct page *page = pages[nr_pages_ret - 1];
421 /* zero the tail end of the last page, we might be
422 * sending it down to disk
425 kaddr = kmap_atomic(page, KM_USER0);
426 memset(kaddr + offset, 0,
427 PAGE_CACHE_SIZE - offset);
428 kunmap_atomic(kaddr, KM_USER0);
435 trans = btrfs_join_transaction(root);
436 BUG_ON(IS_ERR(trans));
437 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
439 /* lets try to make an inline extent */
440 if (ret || total_in < (actual_end - start)) {
441 /* we didn't compress the entire range, try
442 * to make an uncompressed inline extent.
444 ret = cow_file_range_inline(trans, root, inode,
445 start, end, 0, 0, NULL);
447 /* try making a compressed inline extent */
448 ret = cow_file_range_inline(trans, root, inode,
451 compress_type, pages);
455 * inline extent creation worked, we don't need
456 * to create any more async work items. Unlock
457 * and free up our temp pages.
459 extent_clear_unlock_delalloc(inode,
460 &BTRFS_I(inode)->io_tree,
462 EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
463 EXTENT_CLEAR_DELALLOC |
464 EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK);
466 btrfs_end_transaction(trans, root);
469 btrfs_end_transaction(trans, root);
474 * we aren't doing an inline extent round the compressed size
475 * up to a block size boundary so the allocator does sane
478 total_compressed = (total_compressed + blocksize - 1) &
482 * one last check to make sure the compression is really a
483 * win, compare the page count read with the blocks on disk
485 total_in = (total_in + PAGE_CACHE_SIZE - 1) &
486 ~(PAGE_CACHE_SIZE - 1);
487 if (total_compressed >= total_in) {
490 num_bytes = total_in;
493 if (!will_compress && pages) {
495 * the compression code ran but failed to make things smaller,
496 * free any pages it allocated and our page pointer array
498 for (i = 0; i < nr_pages_ret; i++) {
499 WARN_ON(pages[i]->mapping);
500 page_cache_release(pages[i]);
504 total_compressed = 0;
507 /* flag the file so we don't compress in the future */
508 if (!btrfs_test_opt(root, FORCE_COMPRESS) &&
509 !(BTRFS_I(inode)->force_compress)) {
510 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
516 /* the async work queues will take care of doing actual
517 * allocation on disk for these compressed pages,
518 * and will submit them to the elevator.
520 add_async_extent(async_cow, start, num_bytes,
521 total_compressed, pages, nr_pages_ret,
524 if (start + num_bytes < end) {
531 cleanup_and_bail_uncompressed:
533 * No compression, but we still need to write the pages in
534 * the file we've been given so far. redirty the locked
535 * page if it corresponds to our extent and set things up
536 * for the async work queue to run cow_file_range to do
537 * the normal delalloc dance
539 if (page_offset(locked_page) >= start &&
540 page_offset(locked_page) <= end) {
541 __set_page_dirty_nobuffers(locked_page);
542 /* unlocked later on in the async handlers */
544 add_async_extent(async_cow, start, end - start + 1,
545 0, NULL, 0, BTRFS_COMPRESS_NONE);
553 for (i = 0; i < nr_pages_ret; i++) {
554 WARN_ON(pages[i]->mapping);
555 page_cache_release(pages[i]);
563 * phase two of compressed writeback. This is the ordered portion
564 * of the code, which only gets called in the order the work was
565 * queued. We walk all the async extents created by compress_file_range
566 * and send them down to the disk.
568 static noinline int submit_compressed_extents(struct inode *inode,
569 struct async_cow *async_cow)
571 struct async_extent *async_extent;
573 struct btrfs_trans_handle *trans;
574 struct btrfs_key ins;
575 struct extent_map *em;
576 struct btrfs_root *root = BTRFS_I(inode)->root;
577 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
578 struct extent_io_tree *io_tree;
581 if (list_empty(&async_cow->extents))
585 while (!list_empty(&async_cow->extents)) {
586 async_extent = list_entry(async_cow->extents.next,
587 struct async_extent, list);
588 list_del(&async_extent->list);
590 io_tree = &BTRFS_I(inode)->io_tree;
593 /* did the compression code fall back to uncompressed IO? */
594 if (!async_extent->pages) {
595 int page_started = 0;
596 unsigned long nr_written = 0;
598 lock_extent(io_tree, async_extent->start,
599 async_extent->start +
600 async_extent->ram_size - 1, GFP_NOFS);
602 /* allocate blocks */
603 ret = cow_file_range(inode, async_cow->locked_page,
605 async_extent->start +
606 async_extent->ram_size - 1,
607 &page_started, &nr_written, 0);
610 * if page_started, cow_file_range inserted an
611 * inline extent and took care of all the unlocking
612 * and IO for us. Otherwise, we need to submit
613 * all those pages down to the drive.
615 if (!page_started && !ret)
616 extent_write_locked_range(io_tree,
617 inode, async_extent->start,
618 async_extent->start +
619 async_extent->ram_size - 1,
627 lock_extent(io_tree, async_extent->start,
628 async_extent->start + async_extent->ram_size - 1,
631 trans = btrfs_join_transaction(root);
632 BUG_ON(IS_ERR(trans));
633 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
634 ret = btrfs_reserve_extent(trans, root,
635 async_extent->compressed_size,
636 async_extent->compressed_size,
639 btrfs_end_transaction(trans, root);
643 for (i = 0; i < async_extent->nr_pages; i++) {
644 WARN_ON(async_extent->pages[i]->mapping);
645 page_cache_release(async_extent->pages[i]);
647 kfree(async_extent->pages);
648 async_extent->nr_pages = 0;
649 async_extent->pages = NULL;
650 unlock_extent(io_tree, async_extent->start,
651 async_extent->start +
652 async_extent->ram_size - 1, GFP_NOFS);
657 * here we're doing allocation and writeback of the
660 btrfs_drop_extent_cache(inode, async_extent->start,
661 async_extent->start +
662 async_extent->ram_size - 1, 0);
664 em = alloc_extent_map();
666 em->start = async_extent->start;
667 em->len = async_extent->ram_size;
668 em->orig_start = em->start;
670 em->block_start = ins.objectid;
671 em->block_len = ins.offset;
672 em->bdev = root->fs_info->fs_devices->latest_bdev;
673 em->compress_type = async_extent->compress_type;
674 set_bit(EXTENT_FLAG_PINNED, &em->flags);
675 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
678 write_lock(&em_tree->lock);
679 ret = add_extent_mapping(em_tree, em);
680 write_unlock(&em_tree->lock);
681 if (ret != -EEXIST) {
685 btrfs_drop_extent_cache(inode, async_extent->start,
686 async_extent->start +
687 async_extent->ram_size - 1, 0);
690 ret = btrfs_add_ordered_extent_compress(inode,
693 async_extent->ram_size,
695 BTRFS_ORDERED_COMPRESSED,
696 async_extent->compress_type);
700 * clear dirty, set writeback and unlock the pages.
702 extent_clear_unlock_delalloc(inode,
703 &BTRFS_I(inode)->io_tree,
705 async_extent->start +
706 async_extent->ram_size - 1,
707 NULL, EXTENT_CLEAR_UNLOCK_PAGE |
708 EXTENT_CLEAR_UNLOCK |
709 EXTENT_CLEAR_DELALLOC |
710 EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK);
712 ret = btrfs_submit_compressed_write(inode,
714 async_extent->ram_size,
716 ins.offset, async_extent->pages,
717 async_extent->nr_pages);
720 alloc_hint = ins.objectid + ins.offset;
728 static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
731 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
732 struct extent_map *em;
735 read_lock(&em_tree->lock);
736 em = search_extent_mapping(em_tree, start, num_bytes);
739 * if block start isn't an actual block number then find the
740 * first block in this inode and use that as a hint. If that
741 * block is also bogus then just don't worry about it.
743 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
745 em = search_extent_mapping(em_tree, 0, 0);
746 if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
747 alloc_hint = em->block_start;
751 alloc_hint = em->block_start;
755 read_unlock(&em_tree->lock);
761 * when extent_io.c finds a delayed allocation range in the file,
762 * the call backs end up in this code. The basic idea is to
763 * allocate extents on disk for the range, and create ordered data structs
764 * in ram to track those extents.
766 * locked_page is the page that writepage had locked already. We use
767 * it to make sure we don't do extra locks or unlocks.
769 * *page_started is set to one if we unlock locked_page and do everything
770 * required to start IO on it. It may be clean and already done with
773 static noinline int cow_file_range(struct inode *inode,
774 struct page *locked_page,
775 u64 start, u64 end, int *page_started,
776 unsigned long *nr_written,
779 struct btrfs_root *root = BTRFS_I(inode)->root;
780 struct btrfs_trans_handle *trans;
783 unsigned long ram_size;
786 u64 blocksize = root->sectorsize;
787 struct btrfs_key ins;
788 struct extent_map *em;
789 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
792 BUG_ON(btrfs_is_free_space_inode(root, inode));
793 trans = btrfs_join_transaction(root);
794 BUG_ON(IS_ERR(trans));
795 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
797 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
798 num_bytes = max(blocksize, num_bytes);
799 disk_num_bytes = num_bytes;
802 /* if this is a small write inside eof, kick off defrag */
803 if (end <= BTRFS_I(inode)->disk_i_size && num_bytes < 64 * 1024)
804 btrfs_add_inode_defrag(trans, inode);
807 /* lets try to make an inline extent */
808 ret = cow_file_range_inline(trans, root, inode,
809 start, end, 0, 0, NULL);
811 extent_clear_unlock_delalloc(inode,
812 &BTRFS_I(inode)->io_tree,
814 EXTENT_CLEAR_UNLOCK_PAGE |
815 EXTENT_CLEAR_UNLOCK |
816 EXTENT_CLEAR_DELALLOC |
818 EXTENT_SET_WRITEBACK |
819 EXTENT_END_WRITEBACK);
821 *nr_written = *nr_written +
822 (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
829 BUG_ON(disk_num_bytes >
830 btrfs_super_total_bytes(root->fs_info->super_copy));
832 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
833 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
835 while (disk_num_bytes > 0) {
838 cur_alloc_size = disk_num_bytes;
839 ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
840 root->sectorsize, 0, alloc_hint,
844 em = alloc_extent_map();
847 em->orig_start = em->start;
848 ram_size = ins.offset;
849 em->len = ins.offset;
851 em->block_start = ins.objectid;
852 em->block_len = ins.offset;
853 em->bdev = root->fs_info->fs_devices->latest_bdev;
854 set_bit(EXTENT_FLAG_PINNED, &em->flags);
857 write_lock(&em_tree->lock);
858 ret = add_extent_mapping(em_tree, em);
859 write_unlock(&em_tree->lock);
860 if (ret != -EEXIST) {
864 btrfs_drop_extent_cache(inode, start,
865 start + ram_size - 1, 0);
868 cur_alloc_size = ins.offset;
869 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
870 ram_size, cur_alloc_size, 0);
873 if (root->root_key.objectid ==
874 BTRFS_DATA_RELOC_TREE_OBJECTID) {
875 ret = btrfs_reloc_clone_csums(inode, start,
880 if (disk_num_bytes < cur_alloc_size)
883 /* we're not doing compressed IO, don't unlock the first
884 * page (which the caller expects to stay locked), don't
885 * clear any dirty bits and don't set any writeback bits
887 * Do set the Private2 bit so we know this page was properly
888 * setup for writepage
890 op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0;
891 op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
894 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
895 start, start + ram_size - 1,
897 disk_num_bytes -= cur_alloc_size;
898 num_bytes -= cur_alloc_size;
899 alloc_hint = ins.objectid + ins.offset;
900 start += cur_alloc_size;
904 btrfs_end_transaction(trans, root);
910 * work queue call back to started compression on a file and pages
912 static noinline void async_cow_start(struct btrfs_work *work)
914 struct async_cow *async_cow;
916 async_cow = container_of(work, struct async_cow, work);
918 compress_file_range(async_cow->inode, async_cow->locked_page,
919 async_cow->start, async_cow->end, async_cow,
922 async_cow->inode = NULL;
926 * work queue call back to submit previously compressed pages
928 static noinline void async_cow_submit(struct btrfs_work *work)
930 struct async_cow *async_cow;
931 struct btrfs_root *root;
932 unsigned long nr_pages;
934 async_cow = container_of(work, struct async_cow, work);
936 root = async_cow->root;
937 nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >>
940 atomic_sub(nr_pages, &root->fs_info->async_delalloc_pages);
942 if (atomic_read(&root->fs_info->async_delalloc_pages) <
944 waitqueue_active(&root->fs_info->async_submit_wait))
945 wake_up(&root->fs_info->async_submit_wait);
947 if (async_cow->inode)
948 submit_compressed_extents(async_cow->inode, async_cow);
951 static noinline void async_cow_free(struct btrfs_work *work)
953 struct async_cow *async_cow;
954 async_cow = container_of(work, struct async_cow, work);
958 static int cow_file_range_async(struct inode *inode, struct page *locked_page,
959 u64 start, u64 end, int *page_started,
960 unsigned long *nr_written)
962 struct async_cow *async_cow;
963 struct btrfs_root *root = BTRFS_I(inode)->root;
964 unsigned long nr_pages;
966 int limit = 10 * 1024 * 1042;
968 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
969 1, 0, NULL, GFP_NOFS);
970 while (start < end) {
971 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
973 async_cow->inode = inode;
974 async_cow->root = root;
975 async_cow->locked_page = locked_page;
976 async_cow->start = start;
978 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
981 cur_end = min(end, start + 512 * 1024 - 1);
983 async_cow->end = cur_end;
984 INIT_LIST_HEAD(&async_cow->extents);
986 async_cow->work.func = async_cow_start;
987 async_cow->work.ordered_func = async_cow_submit;
988 async_cow->work.ordered_free = async_cow_free;
989 async_cow->work.flags = 0;
991 nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >>
993 atomic_add(nr_pages, &root->fs_info->async_delalloc_pages);
995 btrfs_queue_worker(&root->fs_info->delalloc_workers,
998 if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) {
999 wait_event(root->fs_info->async_submit_wait,
1000 (atomic_read(&root->fs_info->async_delalloc_pages) <
1004 while (atomic_read(&root->fs_info->async_submit_draining) &&
1005 atomic_read(&root->fs_info->async_delalloc_pages)) {
1006 wait_event(root->fs_info->async_submit_wait,
1007 (atomic_read(&root->fs_info->async_delalloc_pages) ==
1011 *nr_written += nr_pages;
1012 start = cur_end + 1;
1018 static noinline int csum_exist_in_range(struct btrfs_root *root,
1019 u64 bytenr, u64 num_bytes)
1022 struct btrfs_ordered_sum *sums;
1025 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr,
1026 bytenr + num_bytes - 1, &list, 0);
1027 if (ret == 0 && list_empty(&list))
1030 while (!list_empty(&list)) {
1031 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
1032 list_del(&sums->list);
1039 * when nowcow writeback call back. This checks for snapshots or COW copies
1040 * of the extents that exist in the file, and COWs the file as required.
1042 * If no cow copies or snapshots exist, we write directly to the existing
1045 static noinline int run_delalloc_nocow(struct inode *inode,
1046 struct page *locked_page,
1047 u64 start, u64 end, int *page_started, int force,
1048 unsigned long *nr_written)
1050 struct btrfs_root *root = BTRFS_I(inode)->root;
1051 struct btrfs_trans_handle *trans;
1052 struct extent_buffer *leaf;
1053 struct btrfs_path *path;
1054 struct btrfs_file_extent_item *fi;
1055 struct btrfs_key found_key;
1068 u64 ino = btrfs_ino(inode);
1070 path = btrfs_alloc_path();
1074 nolock = btrfs_is_free_space_inode(root, inode);
1077 trans = btrfs_join_transaction_nolock(root);
1079 trans = btrfs_join_transaction(root);
1081 BUG_ON(IS_ERR(trans));
1082 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1084 cow_start = (u64)-1;
1087 ret = btrfs_lookup_file_extent(trans, root, path, ino,
1090 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1091 leaf = path->nodes[0];
1092 btrfs_item_key_to_cpu(leaf, &found_key,
1093 path->slots[0] - 1);
1094 if (found_key.objectid == ino &&
1095 found_key.type == BTRFS_EXTENT_DATA_KEY)
1100 leaf = path->nodes[0];
1101 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1102 ret = btrfs_next_leaf(root, path);
1107 leaf = path->nodes[0];
1113 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1115 if (found_key.objectid > ino ||
1116 found_key.type > BTRFS_EXTENT_DATA_KEY ||
1117 found_key.offset > end)
1120 if (found_key.offset > cur_offset) {
1121 extent_end = found_key.offset;
1126 fi = btrfs_item_ptr(leaf, path->slots[0],
1127 struct btrfs_file_extent_item);
1128 extent_type = btrfs_file_extent_type(leaf, fi);
1130 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1131 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1132 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1133 extent_offset = btrfs_file_extent_offset(leaf, fi);
1134 extent_end = found_key.offset +
1135 btrfs_file_extent_num_bytes(leaf, fi);
1136 if (extent_end <= start) {
1140 if (disk_bytenr == 0)
1142 if (btrfs_file_extent_compression(leaf, fi) ||
1143 btrfs_file_extent_encryption(leaf, fi) ||
1144 btrfs_file_extent_other_encoding(leaf, fi))
1146 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1148 if (btrfs_extent_readonly(root, disk_bytenr))
1150 if (btrfs_cross_ref_exist(trans, root, ino,
1152 extent_offset, disk_bytenr))
1154 disk_bytenr += extent_offset;
1155 disk_bytenr += cur_offset - found_key.offset;
1156 num_bytes = min(end + 1, extent_end) - cur_offset;
1158 * force cow if csum exists in the range.
1159 * this ensure that csum for a given extent are
1160 * either valid or do not exist.
1162 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
1165 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1166 extent_end = found_key.offset +
1167 btrfs_file_extent_inline_len(leaf, fi);
1168 extent_end = ALIGN(extent_end, root->sectorsize);
1173 if (extent_end <= start) {
1178 if (cow_start == (u64)-1)
1179 cow_start = cur_offset;
1180 cur_offset = extent_end;
1181 if (cur_offset > end)
1187 btrfs_release_path(path);
1188 if (cow_start != (u64)-1) {
1189 ret = cow_file_range(inode, locked_page, cow_start,
1190 found_key.offset - 1, page_started,
1193 cow_start = (u64)-1;
1196 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1197 struct extent_map *em;
1198 struct extent_map_tree *em_tree;
1199 em_tree = &BTRFS_I(inode)->extent_tree;
1200 em = alloc_extent_map();
1202 em->start = cur_offset;
1203 em->orig_start = em->start;
1204 em->len = num_bytes;
1205 em->block_len = num_bytes;
1206 em->block_start = disk_bytenr;
1207 em->bdev = root->fs_info->fs_devices->latest_bdev;
1208 set_bit(EXTENT_FLAG_PINNED, &em->flags);
1210 write_lock(&em_tree->lock);
1211 ret = add_extent_mapping(em_tree, em);
1212 write_unlock(&em_tree->lock);
1213 if (ret != -EEXIST) {
1214 free_extent_map(em);
1217 btrfs_drop_extent_cache(inode, em->start,
1218 em->start + em->len - 1, 0);
1220 type = BTRFS_ORDERED_PREALLOC;
1222 type = BTRFS_ORDERED_NOCOW;
1225 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr,
1226 num_bytes, num_bytes, type);
1229 if (root->root_key.objectid ==
1230 BTRFS_DATA_RELOC_TREE_OBJECTID) {
1231 ret = btrfs_reloc_clone_csums(inode, cur_offset,
1236 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
1237 cur_offset, cur_offset + num_bytes - 1,
1238 locked_page, EXTENT_CLEAR_UNLOCK_PAGE |
1239 EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
1240 EXTENT_SET_PRIVATE2);
1241 cur_offset = extent_end;
1242 if (cur_offset > end)
1245 btrfs_release_path(path);
1247 if (cur_offset <= end && cow_start == (u64)-1)
1248 cow_start = cur_offset;
1249 if (cow_start != (u64)-1) {
1250 ret = cow_file_range(inode, locked_page, cow_start, end,
1251 page_started, nr_written, 1);
1256 ret = btrfs_end_transaction_nolock(trans, root);
1259 ret = btrfs_end_transaction(trans, root);
1262 btrfs_free_path(path);
1267 * extent_io.c call back to do delayed allocation processing
1269 static int run_delalloc_range(struct inode *inode, struct page *locked_page,
1270 u64 start, u64 end, int *page_started,
1271 unsigned long *nr_written)
1274 struct btrfs_root *root = BTRFS_I(inode)->root;
1276 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW)
1277 ret = run_delalloc_nocow(inode, locked_page, start, end,
1278 page_started, 1, nr_written);
1279 else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)
1280 ret = run_delalloc_nocow(inode, locked_page, start, end,
1281 page_started, 0, nr_written);
1282 else if (!btrfs_test_opt(root, COMPRESS) &&
1283 !(BTRFS_I(inode)->force_compress) &&
1284 !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))
1285 ret = cow_file_range(inode, locked_page, start, end,
1286 page_started, nr_written, 1);
1288 ret = cow_file_range_async(inode, locked_page, start, end,
1289 page_started, nr_written);
1293 static void btrfs_split_extent_hook(struct inode *inode,
1294 struct extent_state *orig, u64 split)
1296 /* not delalloc, ignore it */
1297 if (!(orig->state & EXTENT_DELALLOC))
1300 spin_lock(&BTRFS_I(inode)->lock);
1301 BTRFS_I(inode)->outstanding_extents++;
1302 spin_unlock(&BTRFS_I(inode)->lock);
1306 * extent_io.c merge_extent_hook, used to track merged delayed allocation
1307 * extents so we can keep track of new extents that are just merged onto old
1308 * extents, such as when we are doing sequential writes, so we can properly
1309 * account for the metadata space we'll need.
1311 static void btrfs_merge_extent_hook(struct inode *inode,
1312 struct extent_state *new,
1313 struct extent_state *other)
1315 /* not delalloc, ignore it */
1316 if (!(other->state & EXTENT_DELALLOC))
1319 spin_lock(&BTRFS_I(inode)->lock);
1320 BTRFS_I(inode)->outstanding_extents--;
1321 spin_unlock(&BTRFS_I(inode)->lock);
1325 * extent_io.c set_bit_hook, used to track delayed allocation
1326 * bytes in this file, and to maintain the list of inodes that
1327 * have pending delalloc work to be done.
1329 static void btrfs_set_bit_hook(struct inode *inode,
1330 struct extent_state *state, int *bits)
1334 * set_bit and clear bit hooks normally require _irqsave/restore
1335 * but in this case, we are only testing for the DELALLOC
1336 * bit, which is only set or cleared with irqs on
1338 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1339 struct btrfs_root *root = BTRFS_I(inode)->root;
1340 u64 len = state->end + 1 - state->start;
1341 bool do_list = !btrfs_is_free_space_inode(root, inode);
1343 if (*bits & EXTENT_FIRST_DELALLOC) {
1344 *bits &= ~EXTENT_FIRST_DELALLOC;
1346 spin_lock(&BTRFS_I(inode)->lock);
1347 BTRFS_I(inode)->outstanding_extents++;
1348 spin_unlock(&BTRFS_I(inode)->lock);
1351 spin_lock(&root->fs_info->delalloc_lock);
1352 BTRFS_I(inode)->delalloc_bytes += len;
1353 root->fs_info->delalloc_bytes += len;
1354 if (do_list && list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1355 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1356 &root->fs_info->delalloc_inodes);
1358 spin_unlock(&root->fs_info->delalloc_lock);
1363 * extent_io.c clear_bit_hook, see set_bit_hook for why
1365 static void btrfs_clear_bit_hook(struct inode *inode,
1366 struct extent_state *state, int *bits)
1369 * set_bit and clear bit hooks normally require _irqsave/restore
1370 * but in this case, we are only testing for the DELALLOC
1371 * bit, which is only set or cleared with irqs on
1373 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1374 struct btrfs_root *root = BTRFS_I(inode)->root;
1375 u64 len = state->end + 1 - state->start;
1376 bool do_list = !btrfs_is_free_space_inode(root, inode);
1378 if (*bits & EXTENT_FIRST_DELALLOC) {
1379 *bits &= ~EXTENT_FIRST_DELALLOC;
1380 } else if (!(*bits & EXTENT_DO_ACCOUNTING)) {
1381 spin_lock(&BTRFS_I(inode)->lock);
1382 BTRFS_I(inode)->outstanding_extents--;
1383 spin_unlock(&BTRFS_I(inode)->lock);
1386 if (*bits & EXTENT_DO_ACCOUNTING)
1387 btrfs_delalloc_release_metadata(inode, len);
1389 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
1391 btrfs_free_reserved_data_space(inode, len);
1393 spin_lock(&root->fs_info->delalloc_lock);
1394 root->fs_info->delalloc_bytes -= len;
1395 BTRFS_I(inode)->delalloc_bytes -= len;
1397 if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 &&
1398 !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1399 list_del_init(&BTRFS_I(inode)->delalloc_inodes);
1401 spin_unlock(&root->fs_info->delalloc_lock);
1406 * extent_io.c merge_bio_hook, this must check the chunk tree to make sure
1407 * we don't create bios that span stripes or chunks
1409 int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
1410 size_t size, struct bio *bio,
1411 unsigned long bio_flags)
1413 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
1414 struct btrfs_mapping_tree *map_tree;
1415 u64 logical = (u64)bio->bi_sector << 9;
1420 if (bio_flags & EXTENT_BIO_COMPRESSED)
1423 length = bio->bi_size;
1424 map_tree = &root->fs_info->mapping_tree;
1425 map_length = length;
1426 ret = btrfs_map_block(map_tree, READ, logical,
1427 &map_length, NULL, 0);
1429 if (map_length < length + size)
1435 * in order to insert checksums into the metadata in large chunks,
1436 * we wait until bio submission time. All the pages in the bio are
1437 * checksummed and sums are attached onto the ordered extent record.
1439 * At IO completion time the cums attached on the ordered extent record
1440 * are inserted into the btree
1442 static int __btrfs_submit_bio_start(struct inode *inode, int rw,
1443 struct bio *bio, int mirror_num,
1444 unsigned long bio_flags,
1447 struct btrfs_root *root = BTRFS_I(inode)->root;
1450 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1456 * in order to insert checksums into the metadata in large chunks,
1457 * we wait until bio submission time. All the pages in the bio are
1458 * checksummed and sums are attached onto the ordered extent record.
1460 * At IO completion time the cums attached on the ordered extent record
1461 * are inserted into the btree
1463 static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
1464 int mirror_num, unsigned long bio_flags,
1467 struct btrfs_root *root = BTRFS_I(inode)->root;
1468 return btrfs_map_bio(root, rw, bio, mirror_num, 1);
1472 * extent_io.c submission hook. This does the right thing for csum calculation
1473 * on write, or reading the csums from the tree before a read
1475 static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
1476 int mirror_num, unsigned long bio_flags,
1479 struct btrfs_root *root = BTRFS_I(inode)->root;
1483 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
1485 if (btrfs_is_free_space_inode(root, inode))
1486 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 2);
1488 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
1491 if (!(rw & REQ_WRITE)) {
1492 if (bio_flags & EXTENT_BIO_COMPRESSED) {
1493 return btrfs_submit_compressed_read(inode, bio,
1494 mirror_num, bio_flags);
1495 } else if (!skip_sum) {
1496 ret = btrfs_lookup_bio_sums(root, inode, bio, NULL);
1501 } else if (!skip_sum) {
1502 /* csum items have already been cloned */
1503 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
1505 /* we're doing a write, do the async checksumming */
1506 return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
1507 inode, rw, bio, mirror_num,
1508 bio_flags, bio_offset,
1509 __btrfs_submit_bio_start,
1510 __btrfs_submit_bio_done);
1514 return btrfs_map_bio(root, rw, bio, mirror_num, 0);
1518 * given a list of ordered sums record them in the inode. This happens
1519 * at IO completion time based on sums calculated at bio submission time.
1521 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
1522 struct inode *inode, u64 file_offset,
1523 struct list_head *list)
1525 struct btrfs_ordered_sum *sum;
1527 list_for_each_entry(sum, list, list) {
1528 btrfs_csum_file_blocks(trans,
1529 BTRFS_I(inode)->root->fs_info->csum_root, sum);
1534 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
1535 struct extent_state **cached_state)
1537 if ((end & (PAGE_CACHE_SIZE - 1)) == 0)
1539 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
1540 cached_state, GFP_NOFS);
1543 /* see btrfs_writepage_start_hook for details on why this is required */
1544 struct btrfs_writepage_fixup {
1546 struct btrfs_work work;
1549 static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
1551 struct btrfs_writepage_fixup *fixup;
1552 struct btrfs_ordered_extent *ordered;
1553 struct extent_state *cached_state = NULL;
1555 struct inode *inode;
1559 fixup = container_of(work, struct btrfs_writepage_fixup, work);
1563 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
1564 ClearPageChecked(page);
1568 inode = page->mapping->host;
1569 page_start = page_offset(page);
1570 page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
1572 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 0,
1573 &cached_state, GFP_NOFS);
1575 /* already ordered? We're done */
1576 if (PagePrivate2(page))
1579 ordered = btrfs_lookup_ordered_extent(inode, page_start);
1581 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start,
1582 page_end, &cached_state, GFP_NOFS);
1584 btrfs_start_ordered_extent(inode, ordered, 1);
1589 btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state);
1590 ClearPageChecked(page);
1592 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
1593 &cached_state, GFP_NOFS);
1596 page_cache_release(page);
1601 * There are a few paths in the higher layers of the kernel that directly
1602 * set the page dirty bit without asking the filesystem if it is a
1603 * good idea. This causes problems because we want to make sure COW
1604 * properly happens and the data=ordered rules are followed.
1606 * In our case any range that doesn't have the ORDERED bit set
1607 * hasn't been properly setup for IO. We kick off an async process
1608 * to fix it up. The async helper will wait for ordered extents, set
1609 * the delalloc bit and make it safe to write the page.
1611 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
1613 struct inode *inode = page->mapping->host;
1614 struct btrfs_writepage_fixup *fixup;
1615 struct btrfs_root *root = BTRFS_I(inode)->root;
1617 /* this page is properly in the ordered list */
1618 if (TestClearPagePrivate2(page))
1621 if (PageChecked(page))
1624 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
1628 SetPageChecked(page);
1629 page_cache_get(page);
1630 fixup->work.func = btrfs_writepage_fixup_worker;
1632 btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
1636 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
1637 struct inode *inode, u64 file_pos,
1638 u64 disk_bytenr, u64 disk_num_bytes,
1639 u64 num_bytes, u64 ram_bytes,
1640 u8 compression, u8 encryption,
1641 u16 other_encoding, int extent_type)
1643 struct btrfs_root *root = BTRFS_I(inode)->root;
1644 struct btrfs_file_extent_item *fi;
1645 struct btrfs_path *path;
1646 struct extent_buffer *leaf;
1647 struct btrfs_key ins;
1651 path = btrfs_alloc_path();
1655 path->leave_spinning = 1;
1658 * we may be replacing one extent in the tree with another.
1659 * The new extent is pinned in the extent map, and we don't want
1660 * to drop it from the cache until it is completely in the btree.
1662 * So, tell btrfs_drop_extents to leave this extent in the cache.
1663 * the caller is expected to unpin it and allow it to be merged
1666 ret = btrfs_drop_extents(trans, inode, file_pos, file_pos + num_bytes,
1670 ins.objectid = btrfs_ino(inode);
1671 ins.offset = file_pos;
1672 ins.type = BTRFS_EXTENT_DATA_KEY;
1673 ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*fi));
1675 leaf = path->nodes[0];
1676 fi = btrfs_item_ptr(leaf, path->slots[0],
1677 struct btrfs_file_extent_item);
1678 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1679 btrfs_set_file_extent_type(leaf, fi, extent_type);
1680 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
1681 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
1682 btrfs_set_file_extent_offset(leaf, fi, 0);
1683 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
1684 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
1685 btrfs_set_file_extent_compression(leaf, fi, compression);
1686 btrfs_set_file_extent_encryption(leaf, fi, encryption);
1687 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
1689 btrfs_unlock_up_safe(path, 1);
1690 btrfs_set_lock_blocking(leaf);
1692 btrfs_mark_buffer_dirty(leaf);
1694 inode_add_bytes(inode, num_bytes);
1696 ins.objectid = disk_bytenr;
1697 ins.offset = disk_num_bytes;
1698 ins.type = BTRFS_EXTENT_ITEM_KEY;
1699 ret = btrfs_alloc_reserved_file_extent(trans, root,
1700 root->root_key.objectid,
1701 btrfs_ino(inode), file_pos, &ins);
1703 btrfs_free_path(path);
1709 * helper function for btrfs_finish_ordered_io, this
1710 * just reads in some of the csum leaves to prime them into ram
1711 * before we start the transaction. It limits the amount of btree
1712 * reads required while inside the transaction.
1714 /* as ordered data IO finishes, this gets called so we can finish
1715 * an ordered extent if the range of bytes in the file it covers are
1718 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
1720 struct btrfs_root *root = BTRFS_I(inode)->root;
1721 struct btrfs_trans_handle *trans = NULL;
1722 struct btrfs_ordered_extent *ordered_extent = NULL;
1723 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1724 struct extent_state *cached_state = NULL;
1725 int compress_type = 0;
1729 ret = btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
1733 BUG_ON(!ordered_extent);
1735 nolock = btrfs_is_free_space_inode(root, inode);
1737 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
1738 BUG_ON(!list_empty(&ordered_extent->list));
1739 ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
1742 trans = btrfs_join_transaction_nolock(root);
1744 trans = btrfs_join_transaction(root);
1745 BUG_ON(IS_ERR(trans));
1746 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1747 ret = btrfs_update_inode_fallback(trans, root, inode);
1753 lock_extent_bits(io_tree, ordered_extent->file_offset,
1754 ordered_extent->file_offset + ordered_extent->len - 1,
1755 0, &cached_state, GFP_NOFS);
1758 trans = btrfs_join_transaction_nolock(root);
1760 trans = btrfs_join_transaction(root);
1761 BUG_ON(IS_ERR(trans));
1762 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1764 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
1765 compress_type = ordered_extent->compress_type;
1766 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
1767 BUG_ON(compress_type);
1768 ret = btrfs_mark_extent_written(trans, inode,
1769 ordered_extent->file_offset,
1770 ordered_extent->file_offset +
1771 ordered_extent->len);
1774 BUG_ON(root == root->fs_info->tree_root);
1775 ret = insert_reserved_file_extent(trans, inode,
1776 ordered_extent->file_offset,
1777 ordered_extent->start,
1778 ordered_extent->disk_len,
1779 ordered_extent->len,
1780 ordered_extent->len,
1781 compress_type, 0, 0,
1782 BTRFS_FILE_EXTENT_REG);
1783 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
1784 ordered_extent->file_offset,
1785 ordered_extent->len);
1788 unlock_extent_cached(io_tree, ordered_extent->file_offset,
1789 ordered_extent->file_offset +
1790 ordered_extent->len - 1, &cached_state, GFP_NOFS);
1792 add_pending_csums(trans, inode, ordered_extent->file_offset,
1793 &ordered_extent->list);
1795 ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
1796 if (!ret || !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
1797 ret = btrfs_update_inode_fallback(trans, root, inode);
1802 if (root != root->fs_info->tree_root)
1803 btrfs_delalloc_release_metadata(inode, ordered_extent->len);
1806 btrfs_end_transaction_nolock(trans, root);
1808 btrfs_end_transaction(trans, root);
1812 btrfs_put_ordered_extent(ordered_extent);
1813 /* once for the tree */
1814 btrfs_put_ordered_extent(ordered_extent);
1819 static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
1820 struct extent_state *state, int uptodate)
1822 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate);
1824 ClearPagePrivate2(page);
1825 return btrfs_finish_ordered_io(page->mapping->host, start, end);
1829 * when reads are done, we need to check csums to verify the data is correct
1830 * if there's a match, we allow the bio to finish. If not, the code in
1831 * extent_io.c will try to find good copies for us.
1833 static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
1834 struct extent_state *state)
1836 size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
1837 struct inode *inode = page->mapping->host;
1838 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1840 u64 private = ~(u32)0;
1842 struct btrfs_root *root = BTRFS_I(inode)->root;
1845 if (PageChecked(page)) {
1846 ClearPageChecked(page);
1850 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
1853 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
1854 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
1855 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM,
1860 if (state && state->start == start) {
1861 private = state->private;
1864 ret = get_state_private(io_tree, start, &private);
1866 kaddr = kmap_atomic(page, KM_USER0);
1870 csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1);
1871 btrfs_csum_final(csum, (char *)&csum);
1872 if (csum != private)
1875 kunmap_atomic(kaddr, KM_USER0);
1880 printk_ratelimited(KERN_INFO "btrfs csum failed ino %llu off %llu csum %u "
1882 (unsigned long long)btrfs_ino(page->mapping->host),
1883 (unsigned long long)start, csum,
1884 (unsigned long long)private);
1885 memset(kaddr + offset, 1, end - start + 1);
1886 flush_dcache_page(page);
1887 kunmap_atomic(kaddr, KM_USER0);
1893 struct delayed_iput {
1894 struct list_head list;
1895 struct inode *inode;
1898 void btrfs_add_delayed_iput(struct inode *inode)
1900 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
1901 struct delayed_iput *delayed;
1903 if (atomic_add_unless(&inode->i_count, -1, 1))
1906 delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL);
1907 delayed->inode = inode;
1909 spin_lock(&fs_info->delayed_iput_lock);
1910 list_add_tail(&delayed->list, &fs_info->delayed_iputs);
1911 spin_unlock(&fs_info->delayed_iput_lock);
1914 void btrfs_run_delayed_iputs(struct btrfs_root *root)
1917 struct btrfs_fs_info *fs_info = root->fs_info;
1918 struct delayed_iput *delayed;
1921 spin_lock(&fs_info->delayed_iput_lock);
1922 empty = list_empty(&fs_info->delayed_iputs);
1923 spin_unlock(&fs_info->delayed_iput_lock);
1927 down_read(&root->fs_info->cleanup_work_sem);
1928 spin_lock(&fs_info->delayed_iput_lock);
1929 list_splice_init(&fs_info->delayed_iputs, &list);
1930 spin_unlock(&fs_info->delayed_iput_lock);
1932 while (!list_empty(&list)) {
1933 delayed = list_entry(list.next, struct delayed_iput, list);
1934 list_del(&delayed->list);
1935 iput(delayed->inode);
1938 up_read(&root->fs_info->cleanup_work_sem);
1941 enum btrfs_orphan_cleanup_state {
1942 ORPHAN_CLEANUP_STARTED = 1,
1943 ORPHAN_CLEANUP_DONE = 2,
1947 * This is called in transaction commmit time. If there are no orphan
1948 * files in the subvolume, it removes orphan item and frees block_rsv
1951 void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans,
1952 struct btrfs_root *root)
1956 if (!list_empty(&root->orphan_list) ||
1957 root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE)
1960 if (root->orphan_item_inserted &&
1961 btrfs_root_refs(&root->root_item) > 0) {
1962 ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root,
1963 root->root_key.objectid);
1965 root->orphan_item_inserted = 0;
1968 if (root->orphan_block_rsv) {
1969 WARN_ON(root->orphan_block_rsv->size > 0);
1970 btrfs_free_block_rsv(root, root->orphan_block_rsv);
1971 root->orphan_block_rsv = NULL;
1976 * This creates an orphan entry for the given inode in case something goes
1977 * wrong in the middle of an unlink/truncate.
1979 * NOTE: caller of this function should reserve 5 units of metadata for
1982 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
1984 struct btrfs_root *root = BTRFS_I(inode)->root;
1985 struct btrfs_block_rsv *block_rsv = NULL;
1990 if (!root->orphan_block_rsv) {
1991 block_rsv = btrfs_alloc_block_rsv(root);
1996 spin_lock(&root->orphan_lock);
1997 if (!root->orphan_block_rsv) {
1998 root->orphan_block_rsv = block_rsv;
1999 } else if (block_rsv) {
2000 btrfs_free_block_rsv(root, block_rsv);
2004 if (list_empty(&BTRFS_I(inode)->i_orphan)) {
2005 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
2008 * For proper ENOSPC handling, we should do orphan
2009 * cleanup when mounting. But this introduces backward
2010 * compatibility issue.
2012 if (!xchg(&root->orphan_item_inserted, 1))
2020 if (!BTRFS_I(inode)->orphan_meta_reserved) {
2021 BTRFS_I(inode)->orphan_meta_reserved = 1;
2024 spin_unlock(&root->orphan_lock);
2026 /* grab metadata reservation from transaction handle */
2028 ret = btrfs_orphan_reserve_metadata(trans, inode);
2032 /* insert an orphan item to track this unlinked/truncated file */
2034 ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode));
2035 BUG_ON(ret && ret != -EEXIST);
2038 /* insert an orphan item to track subvolume contains orphan files */
2040 ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
2041 root->root_key.objectid);
2048 * We have done the truncate/delete so we can go ahead and remove the orphan
2049 * item for this particular inode.
2051 int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode)
2053 struct btrfs_root *root = BTRFS_I(inode)->root;
2054 int delete_item = 0;
2055 int release_rsv = 0;
2058 spin_lock(&root->orphan_lock);
2059 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
2060 list_del_init(&BTRFS_I(inode)->i_orphan);
2064 if (BTRFS_I(inode)->orphan_meta_reserved) {
2065 BTRFS_I(inode)->orphan_meta_reserved = 0;
2068 spin_unlock(&root->orphan_lock);
2070 if (trans && delete_item) {
2071 ret = btrfs_del_orphan_item(trans, root, btrfs_ino(inode));
2076 btrfs_orphan_release_metadata(inode);
2082 * this cleans up any orphans that may be left on the list from the last use
2085 int btrfs_orphan_cleanup(struct btrfs_root *root)
2087 struct btrfs_path *path;
2088 struct extent_buffer *leaf;
2089 struct btrfs_key key, found_key;
2090 struct btrfs_trans_handle *trans;
2091 struct inode *inode;
2092 u64 last_objectid = 0;
2093 int ret = 0, nr_unlink = 0, nr_truncate = 0;
2095 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
2098 path = btrfs_alloc_path();
2105 key.objectid = BTRFS_ORPHAN_OBJECTID;
2106 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
2107 key.offset = (u64)-1;
2110 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2115 * if ret == 0 means we found what we were searching for, which
2116 * is weird, but possible, so only screw with path if we didn't
2117 * find the key and see if we have stuff that matches
2121 if (path->slots[0] == 0)
2126 /* pull out the item */
2127 leaf = path->nodes[0];
2128 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2130 /* make sure the item matches what we want */
2131 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
2133 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
2136 /* release the path since we're done with it */
2137 btrfs_release_path(path);
2140 * this is where we are basically btrfs_lookup, without the
2141 * crossing root thing. we store the inode number in the
2142 * offset of the orphan item.
2145 if (found_key.offset == last_objectid) {
2146 printk(KERN_ERR "btrfs: Error removing orphan entry, "
2147 "stopping orphan cleanup\n");
2152 last_objectid = found_key.offset;
2154 found_key.objectid = found_key.offset;
2155 found_key.type = BTRFS_INODE_ITEM_KEY;
2156 found_key.offset = 0;
2157 inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL);
2158 ret = PTR_RET(inode);
2159 if (ret && ret != -ESTALE)
2162 if (ret == -ESTALE && root == root->fs_info->tree_root) {
2163 struct btrfs_root *dead_root;
2164 struct btrfs_fs_info *fs_info = root->fs_info;
2165 int is_dead_root = 0;
2168 * this is an orphan in the tree root. Currently these
2169 * could come from 2 sources:
2170 * a) a snapshot deletion in progress
2171 * b) a free space cache inode
2172 * We need to distinguish those two, as the snapshot
2173 * orphan must not get deleted.
2174 * find_dead_roots already ran before us, so if this
2175 * is a snapshot deletion, we should find the root
2176 * in the dead_roots list
2178 spin_lock(&fs_info->trans_lock);
2179 list_for_each_entry(dead_root, &fs_info->dead_roots,
2181 if (dead_root->root_key.objectid ==
2182 found_key.objectid) {
2187 spin_unlock(&fs_info->trans_lock);
2189 /* prevent this orphan from being found again */
2190 key.offset = found_key.objectid - 1;
2195 * Inode is already gone but the orphan item is still there,
2196 * kill the orphan item.
2198 if (ret == -ESTALE) {
2199 trans = btrfs_start_transaction(root, 1);
2200 if (IS_ERR(trans)) {
2201 ret = PTR_ERR(trans);
2204 ret = btrfs_del_orphan_item(trans, root,
2205 found_key.objectid);
2207 btrfs_end_transaction(trans, root);
2212 * add this inode to the orphan list so btrfs_orphan_del does
2213 * the proper thing when we hit it
2215 spin_lock(&root->orphan_lock);
2216 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
2217 spin_unlock(&root->orphan_lock);
2219 /* if we have links, this was a truncate, lets do that */
2220 if (inode->i_nlink) {
2221 if (!S_ISREG(inode->i_mode)) {
2228 * Need to hold the imutex for reservation purposes, not
2229 * a huge deal here but I have a WARN_ON in
2230 * btrfs_delalloc_reserve_space to catch offenders.
2232 mutex_lock(&inode->i_mutex);
2233 ret = btrfs_truncate(inode);
2234 mutex_unlock(&inode->i_mutex);
2239 /* this will do delete_inode and everything for us */
2244 /* release the path since we're done with it */
2245 btrfs_release_path(path);
2247 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
2249 if (root->orphan_block_rsv)
2250 btrfs_block_rsv_release(root, root->orphan_block_rsv,
2253 if (root->orphan_block_rsv || root->orphan_item_inserted) {
2254 trans = btrfs_join_transaction(root);
2256 btrfs_end_transaction(trans, root);
2260 printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink);
2262 printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate);
2266 printk(KERN_CRIT "btrfs: could not do orphan cleanup %d\n", ret);
2267 btrfs_free_path(path);
2272 * very simple check to peek ahead in the leaf looking for xattrs. If we
2273 * don't find any xattrs, we know there can't be any acls.
2275 * slot is the slot the inode is in, objectid is the objectid of the inode
2277 static noinline int acls_after_inode_item(struct extent_buffer *leaf,
2278 int slot, u64 objectid)
2280 u32 nritems = btrfs_header_nritems(leaf);
2281 struct btrfs_key found_key;
2285 while (slot < nritems) {
2286 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2288 /* we found a different objectid, there must not be acls */
2289 if (found_key.objectid != objectid)
2292 /* we found an xattr, assume we've got an acl */
2293 if (found_key.type == BTRFS_XATTR_ITEM_KEY)
2297 * we found a key greater than an xattr key, there can't
2298 * be any acls later on
2300 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
2307 * it goes inode, inode backrefs, xattrs, extents,
2308 * so if there are a ton of hard links to an inode there can
2309 * be a lot of backrefs. Don't waste time searching too hard,
2310 * this is just an optimization
2315 /* we hit the end of the leaf before we found an xattr or
2316 * something larger than an xattr. We have to assume the inode
2323 * read an inode from the btree into the in-memory inode
2325 static void btrfs_read_locked_inode(struct inode *inode)
2327 struct btrfs_path *path;
2328 struct extent_buffer *leaf;
2329 struct btrfs_inode_item *inode_item;
2330 struct btrfs_timespec *tspec;
2331 struct btrfs_root *root = BTRFS_I(inode)->root;
2332 struct btrfs_key location;
2336 bool filled = false;
2338 ret = btrfs_fill_inode(inode, &rdev);
2342 path = btrfs_alloc_path();
2346 path->leave_spinning = 1;
2347 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
2349 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
2353 leaf = path->nodes[0];
2358 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2359 struct btrfs_inode_item);
2360 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
2361 set_nlink(inode, btrfs_inode_nlink(leaf, inode_item));
2362 inode->i_uid = btrfs_inode_uid(leaf, inode_item);
2363 inode->i_gid = btrfs_inode_gid(leaf, inode_item);
2364 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
2366 tspec = btrfs_inode_atime(inode_item);
2367 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2368 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2370 tspec = btrfs_inode_mtime(inode_item);
2371 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2372 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2374 tspec = btrfs_inode_ctime(inode_item);
2375 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2376 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2378 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
2379 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
2380 BTRFS_I(inode)->sequence = btrfs_inode_sequence(leaf, inode_item);
2381 inode->i_generation = BTRFS_I(inode)->generation;
2383 rdev = btrfs_inode_rdev(leaf, inode_item);
2385 BTRFS_I(inode)->index_cnt = (u64)-1;
2386 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
2389 * try to precache a NULL acl entry for files that don't have
2390 * any xattrs or acls
2392 maybe_acls = acls_after_inode_item(leaf, path->slots[0],
2395 cache_no_acl(inode);
2397 btrfs_free_path(path);
2399 switch (inode->i_mode & S_IFMT) {
2401 inode->i_mapping->a_ops = &btrfs_aops;
2402 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2403 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
2404 inode->i_fop = &btrfs_file_operations;
2405 inode->i_op = &btrfs_file_inode_operations;
2408 inode->i_fop = &btrfs_dir_file_operations;
2409 if (root == root->fs_info->tree_root)
2410 inode->i_op = &btrfs_dir_ro_inode_operations;
2412 inode->i_op = &btrfs_dir_inode_operations;
2415 inode->i_op = &btrfs_symlink_inode_operations;
2416 inode->i_mapping->a_ops = &btrfs_symlink_aops;
2417 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2420 inode->i_op = &btrfs_special_inode_operations;
2421 init_special_inode(inode, inode->i_mode, rdev);
2425 btrfs_update_iflags(inode);
2429 btrfs_free_path(path);
2430 make_bad_inode(inode);
2434 * given a leaf and an inode, copy the inode fields into the leaf
2436 static void fill_inode_item(struct btrfs_trans_handle *trans,
2437 struct extent_buffer *leaf,
2438 struct btrfs_inode_item *item,
2439 struct inode *inode)
2441 btrfs_set_inode_uid(leaf, item, inode->i_uid);
2442 btrfs_set_inode_gid(leaf, item, inode->i_gid);
2443 btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size);
2444 btrfs_set_inode_mode(leaf, item, inode->i_mode);
2445 btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
2447 btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
2448 inode->i_atime.tv_sec);
2449 btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
2450 inode->i_atime.tv_nsec);
2452 btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
2453 inode->i_mtime.tv_sec);
2454 btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
2455 inode->i_mtime.tv_nsec);
2457 btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
2458 inode->i_ctime.tv_sec);
2459 btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
2460 inode->i_ctime.tv_nsec);
2462 btrfs_set_inode_nbytes(leaf, item, inode_get_bytes(inode));
2463 btrfs_set_inode_generation(leaf, item, BTRFS_I(inode)->generation);
2464 btrfs_set_inode_sequence(leaf, item, BTRFS_I(inode)->sequence);
2465 btrfs_set_inode_transid(leaf, item, trans->transid);
2466 btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
2467 btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
2468 btrfs_set_inode_block_group(leaf, item, 0);
2472 * copy everything in the in-memory inode into the btree.
2474 static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans,
2475 struct btrfs_root *root, struct inode *inode)
2477 struct btrfs_inode_item *inode_item;
2478 struct btrfs_path *path;
2479 struct extent_buffer *leaf;
2482 path = btrfs_alloc_path();
2486 path->leave_spinning = 1;
2487 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location,
2495 btrfs_unlock_up_safe(path, 1);
2496 leaf = path->nodes[0];
2497 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2498 struct btrfs_inode_item);
2500 fill_inode_item(trans, leaf, inode_item, inode);
2501 btrfs_mark_buffer_dirty(leaf);
2502 btrfs_set_inode_last_trans(trans, inode);
2505 btrfs_free_path(path);
2510 * copy everything in the in-memory inode into the btree.
2512 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
2513 struct btrfs_root *root, struct inode *inode)
2518 * If the inode is a free space inode, we can deadlock during commit
2519 * if we put it into the delayed code.
2521 * The data relocation inode should also be directly updated
2524 if (!btrfs_is_free_space_inode(root, inode)
2525 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID) {
2526 ret = btrfs_delayed_update_inode(trans, root, inode);
2528 btrfs_set_inode_last_trans(trans, inode);
2532 return btrfs_update_inode_item(trans, root, inode);
2535 static noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
2536 struct btrfs_root *root, struct inode *inode)
2540 ret = btrfs_update_inode(trans, root, inode);
2542 return btrfs_update_inode_item(trans, root, inode);
2547 * unlink helper that gets used here in inode.c and in the tree logging
2548 * recovery code. It remove a link in a directory with a given name, and
2549 * also drops the back refs in the inode to the directory
2551 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
2552 struct btrfs_root *root,
2553 struct inode *dir, struct inode *inode,
2554 const char *name, int name_len)
2556 struct btrfs_path *path;
2558 struct extent_buffer *leaf;
2559 struct btrfs_dir_item *di;
2560 struct btrfs_key key;
2562 u64 ino = btrfs_ino(inode);
2563 u64 dir_ino = btrfs_ino(dir);
2565 path = btrfs_alloc_path();
2571 path->leave_spinning = 1;
2572 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
2573 name, name_len, -1);
2582 leaf = path->nodes[0];
2583 btrfs_dir_item_key_to_cpu(leaf, di, &key);
2584 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2587 btrfs_release_path(path);
2589 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino,
2592 printk(KERN_INFO "btrfs failed to delete reference to %.*s, "
2593 "inode %llu parent %llu\n", name_len, name,
2594 (unsigned long long)ino, (unsigned long long)dir_ino);
2598 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
2602 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
2604 BUG_ON(ret != 0 && ret != -ENOENT);
2606 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
2611 btrfs_free_path(path);
2615 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
2616 inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
2617 btrfs_update_inode(trans, root, dir);
2622 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
2623 struct btrfs_root *root,
2624 struct inode *dir, struct inode *inode,
2625 const char *name, int name_len)
2628 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
2630 btrfs_drop_nlink(inode);
2631 ret = btrfs_update_inode(trans, root, inode);
2637 /* helper to check if there is any shared block in the path */
2638 static int check_path_shared(struct btrfs_root *root,
2639 struct btrfs_path *path)
2641 struct extent_buffer *eb;
2645 for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
2648 if (!path->nodes[level])
2650 eb = path->nodes[level];
2651 if (!btrfs_block_can_be_shared(root, eb))
2653 ret = btrfs_lookup_extent_info(NULL, root, eb->start, eb->len,
2662 * helper to start transaction for unlink and rmdir.
2664 * unlink and rmdir are special in btrfs, they do not always free space.
2665 * so in enospc case, we should make sure they will free space before
2666 * allowing them to use the global metadata reservation.
2668 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir,
2669 struct dentry *dentry)
2671 struct btrfs_trans_handle *trans;
2672 struct btrfs_root *root = BTRFS_I(dir)->root;
2673 struct btrfs_path *path;
2674 struct btrfs_inode_ref *ref;
2675 struct btrfs_dir_item *di;
2676 struct inode *inode = dentry->d_inode;
2681 u64 ino = btrfs_ino(inode);
2682 u64 dir_ino = btrfs_ino(dir);
2685 * 1 for the possible orphan item
2686 * 1 for the dir item
2687 * 1 for the dir index
2688 * 1 for the inode ref
2689 * 1 for the inode ref in the tree log
2690 * 2 for the dir entries in the log
2693 trans = btrfs_start_transaction(root, 8);
2694 if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
2697 if (ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
2698 return ERR_PTR(-ENOSPC);
2700 /* check if there is someone else holds reference */
2701 if (S_ISDIR(inode->i_mode) && atomic_read(&inode->i_count) > 1)
2702 return ERR_PTR(-ENOSPC);
2704 if (atomic_read(&inode->i_count) > 2)
2705 return ERR_PTR(-ENOSPC);
2707 if (xchg(&root->fs_info->enospc_unlink, 1))
2708 return ERR_PTR(-ENOSPC);
2710 path = btrfs_alloc_path();
2712 root->fs_info->enospc_unlink = 0;
2713 return ERR_PTR(-ENOMEM);
2716 /* 1 for the orphan item */
2717 trans = btrfs_start_transaction(root, 1);
2718 if (IS_ERR(trans)) {
2719 btrfs_free_path(path);
2720 root->fs_info->enospc_unlink = 0;
2724 path->skip_locking = 1;
2725 path->search_commit_root = 1;
2727 ret = btrfs_lookup_inode(trans, root, path,
2728 &BTRFS_I(dir)->location, 0);
2734 if (check_path_shared(root, path))
2739 btrfs_release_path(path);
2741 ret = btrfs_lookup_inode(trans, root, path,
2742 &BTRFS_I(inode)->location, 0);
2748 if (check_path_shared(root, path))
2753 btrfs_release_path(path);
2755 if (ret == 0 && S_ISREG(inode->i_mode)) {
2756 ret = btrfs_lookup_file_extent(trans, root, path,
2763 if (check_path_shared(root, path))
2765 btrfs_release_path(path);
2773 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
2774 dentry->d_name.name, dentry->d_name.len, 0);
2780 if (check_path_shared(root, path))
2786 btrfs_release_path(path);
2788 ref = btrfs_lookup_inode_ref(trans, root, path,
2789 dentry->d_name.name, dentry->d_name.len,
2796 if (check_path_shared(root, path))
2798 index = btrfs_inode_ref_index(path->nodes[0], ref);
2799 btrfs_release_path(path);
2802 * This is a commit root search, if we can lookup inode item and other
2803 * relative items in the commit root, it means the transaction of
2804 * dir/file creation has been committed, and the dir index item that we
2805 * delay to insert has also been inserted into the commit root. So
2806 * we needn't worry about the delayed insertion of the dir index item
2809 di = btrfs_lookup_dir_index_item(trans, root, path, dir_ino, index,
2810 dentry->d_name.name, dentry->d_name.len, 0);
2815 BUG_ON(ret == -ENOENT);
2816 if (check_path_shared(root, path))
2821 btrfs_free_path(path);
2822 /* Migrate the orphan reservation over */
2824 err = btrfs_block_rsv_migrate(trans->block_rsv,
2825 &root->fs_info->global_block_rsv,
2826 trans->bytes_reserved);
2829 btrfs_end_transaction(trans, root);
2830 root->fs_info->enospc_unlink = 0;
2831 return ERR_PTR(err);
2834 trans->block_rsv = &root->fs_info->global_block_rsv;
2838 static void __unlink_end_trans(struct btrfs_trans_handle *trans,
2839 struct btrfs_root *root)
2841 if (trans->block_rsv == &root->fs_info->global_block_rsv) {
2842 btrfs_block_rsv_release(root, trans->block_rsv,
2843 trans->bytes_reserved);
2844 trans->block_rsv = &root->fs_info->trans_block_rsv;
2845 BUG_ON(!root->fs_info->enospc_unlink);
2846 root->fs_info->enospc_unlink = 0;
2848 btrfs_end_transaction(trans, root);
2851 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
2853 struct btrfs_root *root = BTRFS_I(dir)->root;
2854 struct btrfs_trans_handle *trans;
2855 struct inode *inode = dentry->d_inode;
2857 unsigned long nr = 0;
2859 trans = __unlink_start_trans(dir, dentry);
2861 return PTR_ERR(trans);
2863 btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0);
2865 ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
2866 dentry->d_name.name, dentry->d_name.len);
2870 if (inode->i_nlink == 0) {
2871 ret = btrfs_orphan_add(trans, inode);
2877 nr = trans->blocks_used;
2878 __unlink_end_trans(trans, root);
2879 btrfs_btree_balance_dirty(root, nr);
2883 int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
2884 struct btrfs_root *root,
2885 struct inode *dir, u64 objectid,
2886 const char *name, int name_len)
2888 struct btrfs_path *path;
2889 struct extent_buffer *leaf;
2890 struct btrfs_dir_item *di;
2891 struct btrfs_key key;
2894 u64 dir_ino = btrfs_ino(dir);
2896 path = btrfs_alloc_path();
2900 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
2901 name, name_len, -1);
2902 BUG_ON(IS_ERR_OR_NULL(di));
2904 leaf = path->nodes[0];
2905 btrfs_dir_item_key_to_cpu(leaf, di, &key);
2906 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
2907 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2909 btrfs_release_path(path);
2911 ret = btrfs_del_root_ref(trans, root->fs_info->tree_root,
2912 objectid, root->root_key.objectid,
2913 dir_ino, &index, name, name_len);
2915 BUG_ON(ret != -ENOENT);
2916 di = btrfs_search_dir_index_item(root, path, dir_ino,
2918 BUG_ON(IS_ERR_OR_NULL(di));
2920 leaf = path->nodes[0];
2921 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2922 btrfs_release_path(path);
2925 btrfs_release_path(path);
2927 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
2930 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
2931 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
2932 ret = btrfs_update_inode(trans, root, dir);
2935 btrfs_free_path(path);
2939 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
2941 struct inode *inode = dentry->d_inode;
2943 struct btrfs_root *root = BTRFS_I(dir)->root;
2944 struct btrfs_trans_handle *trans;
2945 unsigned long nr = 0;
2947 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE ||
2948 btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID)
2951 trans = __unlink_start_trans(dir, dentry);
2953 return PTR_ERR(trans);
2955 if (unlikely(btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
2956 err = btrfs_unlink_subvol(trans, root, dir,
2957 BTRFS_I(inode)->location.objectid,
2958 dentry->d_name.name,
2959 dentry->d_name.len);
2963 err = btrfs_orphan_add(trans, inode);
2967 /* now the directory is empty */
2968 err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
2969 dentry->d_name.name, dentry->d_name.len);
2971 btrfs_i_size_write(inode, 0);
2973 nr = trans->blocks_used;
2974 __unlink_end_trans(trans, root);
2975 btrfs_btree_balance_dirty(root, nr);
2981 * this can truncate away extent items, csum items and directory items.
2982 * It starts at a high offset and removes keys until it can't find
2983 * any higher than new_size
2985 * csum items that cross the new i_size are truncated to the new size
2988 * min_type is the minimum key type to truncate down to. If set to 0, this
2989 * will kill all the items on this inode, including the INODE_ITEM_KEY.
2991 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
2992 struct btrfs_root *root,
2993 struct inode *inode,
2994 u64 new_size, u32 min_type)
2996 struct btrfs_path *path;
2997 struct extent_buffer *leaf;
2998 struct btrfs_file_extent_item *fi;
2999 struct btrfs_key key;
3000 struct btrfs_key found_key;
3001 u64 extent_start = 0;
3002 u64 extent_num_bytes = 0;
3003 u64 extent_offset = 0;
3005 u64 mask = root->sectorsize - 1;
3006 u32 found_type = (u8)-1;
3009 int pending_del_nr = 0;
3010 int pending_del_slot = 0;
3011 int extent_type = -1;
3014 u64 ino = btrfs_ino(inode);
3016 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
3018 path = btrfs_alloc_path();
3023 if (root->ref_cows || root == root->fs_info->tree_root)
3024 btrfs_drop_extent_cache(inode, new_size & (~mask), (u64)-1, 0);
3027 * This function is also used to drop the items in the log tree before
3028 * we relog the inode, so if root != BTRFS_I(inode)->root, it means
3029 * it is used to drop the loged items. So we shouldn't kill the delayed
3032 if (min_type == 0 && root == BTRFS_I(inode)->root)
3033 btrfs_kill_delayed_inode_items(inode);
3036 key.offset = (u64)-1;
3040 path->leave_spinning = 1;
3041 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3048 /* there are no items in the tree for us to truncate, we're
3051 if (path->slots[0] == 0)
3058 leaf = path->nodes[0];
3059 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3060 found_type = btrfs_key_type(&found_key);
3062 if (found_key.objectid != ino)
3065 if (found_type < min_type)
3068 item_end = found_key.offset;
3069 if (found_type == BTRFS_EXTENT_DATA_KEY) {
3070 fi = btrfs_item_ptr(leaf, path->slots[0],
3071 struct btrfs_file_extent_item);
3072 extent_type = btrfs_file_extent_type(leaf, fi);
3073 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
3075 btrfs_file_extent_num_bytes(leaf, fi);
3076 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
3077 item_end += btrfs_file_extent_inline_len(leaf,
3082 if (found_type > min_type) {
3085 if (item_end < new_size)
3087 if (found_key.offset >= new_size)
3093 /* FIXME, shrink the extent if the ref count is only 1 */
3094 if (found_type != BTRFS_EXTENT_DATA_KEY)
3097 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
3099 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
3101 u64 orig_num_bytes =
3102 btrfs_file_extent_num_bytes(leaf, fi);
3103 extent_num_bytes = new_size -
3104 found_key.offset + root->sectorsize - 1;
3105 extent_num_bytes = extent_num_bytes &
3106 ~((u64)root->sectorsize - 1);
3107 btrfs_set_file_extent_num_bytes(leaf, fi,
3109 num_dec = (orig_num_bytes -
3111 if (root->ref_cows && extent_start != 0)
3112 inode_sub_bytes(inode, num_dec);
3113 btrfs_mark_buffer_dirty(leaf);
3116 btrfs_file_extent_disk_num_bytes(leaf,
3118 extent_offset = found_key.offset -
3119 btrfs_file_extent_offset(leaf, fi);
3121 /* FIXME blocksize != 4096 */
3122 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
3123 if (extent_start != 0) {
3126 inode_sub_bytes(inode, num_dec);
3129 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
3131 * we can't truncate inline items that have had
3135 btrfs_file_extent_compression(leaf, fi) == 0 &&
3136 btrfs_file_extent_encryption(leaf, fi) == 0 &&
3137 btrfs_file_extent_other_encoding(leaf, fi) == 0) {
3138 u32 size = new_size - found_key.offset;
3140 if (root->ref_cows) {
3141 inode_sub_bytes(inode, item_end + 1 -
3145 btrfs_file_extent_calc_inline_size(size);
3146 ret = btrfs_truncate_item(trans, root, path,
3148 } else if (root->ref_cows) {
3149 inode_sub_bytes(inode, item_end + 1 -
3155 if (!pending_del_nr) {
3156 /* no pending yet, add ourselves */
3157 pending_del_slot = path->slots[0];
3159 } else if (pending_del_nr &&
3160 path->slots[0] + 1 == pending_del_slot) {
3161 /* hop on the pending chunk */
3163 pending_del_slot = path->slots[0];
3170 if (found_extent && (root->ref_cows ||
3171 root == root->fs_info->tree_root)) {
3172 btrfs_set_path_blocking(path);
3173 ret = btrfs_free_extent(trans, root, extent_start,
3174 extent_num_bytes, 0,
3175 btrfs_header_owner(leaf),
3176 ino, extent_offset, 0);
3180 if (found_type == BTRFS_INODE_ITEM_KEY)
3183 if (path->slots[0] == 0 ||
3184 path->slots[0] != pending_del_slot) {
3185 if (root->ref_cows &&
3186 BTRFS_I(inode)->location.objectid !=
3187 BTRFS_FREE_INO_OBJECTID) {
3191 if (pending_del_nr) {
3192 ret = btrfs_del_items(trans, root, path,
3198 btrfs_release_path(path);
3205 if (pending_del_nr) {
3206 ret = btrfs_del_items(trans, root, path, pending_del_slot,
3210 btrfs_free_path(path);
3215 * taken from block_truncate_page, but does cow as it zeros out
3216 * any bytes left in the last page in the file.
3218 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
3220 struct inode *inode = mapping->host;
3221 struct btrfs_root *root = BTRFS_I(inode)->root;
3222 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3223 struct btrfs_ordered_extent *ordered;
3224 struct extent_state *cached_state = NULL;
3226 u32 blocksize = root->sectorsize;
3227 pgoff_t index = from >> PAGE_CACHE_SHIFT;
3228 unsigned offset = from & (PAGE_CACHE_SIZE-1);
3230 gfp_t mask = btrfs_alloc_write_mask(mapping);
3235 if ((offset & (blocksize - 1)) == 0)
3237 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
3243 page = find_or_create_page(mapping, index, mask);
3245 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
3249 page_start = page_offset(page);
3250 page_end = page_start + PAGE_CACHE_SIZE - 1;
3252 if (!PageUptodate(page)) {
3253 ret = btrfs_readpage(NULL, page);
3255 if (page->mapping != mapping) {
3257 page_cache_release(page);
3260 if (!PageUptodate(page)) {
3265 wait_on_page_writeback(page);
3267 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state,
3269 set_page_extent_mapped(page);
3271 ordered = btrfs_lookup_ordered_extent(inode, page_start);
3273 unlock_extent_cached(io_tree, page_start, page_end,
3274 &cached_state, GFP_NOFS);
3276 page_cache_release(page);
3277 btrfs_start_ordered_extent(inode, ordered, 1);
3278 btrfs_put_ordered_extent(ordered);
3282 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
3283 EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
3284 0, 0, &cached_state, GFP_NOFS);
3286 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
3289 unlock_extent_cached(io_tree, page_start, page_end,
3290 &cached_state, GFP_NOFS);
3295 if (offset != PAGE_CACHE_SIZE) {
3297 memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
3298 flush_dcache_page(page);
3301 ClearPageChecked(page);
3302 set_page_dirty(page);
3303 unlock_extent_cached(io_tree, page_start, page_end, &cached_state,
3308 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
3310 page_cache_release(page);
3316 * This function puts in dummy file extents for the area we're creating a hole
3317 * for. So if we are truncating this file to a larger size we need to insert
3318 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
3319 * the range between oldsize and size
3321 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
3323 struct btrfs_trans_handle *trans;
3324 struct btrfs_root *root = BTRFS_I(inode)->root;
3325 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3326 struct extent_map *em = NULL;
3327 struct extent_state *cached_state = NULL;
3328 u64 mask = root->sectorsize - 1;
3329 u64 hole_start = (oldsize + mask) & ~mask;
3330 u64 block_end = (size + mask) & ~mask;
3336 if (size <= hole_start)
3340 struct btrfs_ordered_extent *ordered;
3341 btrfs_wait_ordered_range(inode, hole_start,
3342 block_end - hole_start);
3343 lock_extent_bits(io_tree, hole_start, block_end - 1, 0,
3344 &cached_state, GFP_NOFS);
3345 ordered = btrfs_lookup_ordered_extent(inode, hole_start);
3348 unlock_extent_cached(io_tree, hole_start, block_end - 1,
3349 &cached_state, GFP_NOFS);
3350 btrfs_put_ordered_extent(ordered);
3353 cur_offset = hole_start;
3355 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
3356 block_end - cur_offset, 0);
3357 BUG_ON(IS_ERR_OR_NULL(em));
3358 last_byte = min(extent_map_end(em), block_end);
3359 last_byte = (last_byte + mask) & ~mask;
3360 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
3362 hole_size = last_byte - cur_offset;
3364 trans = btrfs_start_transaction(root, 3);
3365 if (IS_ERR(trans)) {
3366 err = PTR_ERR(trans);
3370 err = btrfs_drop_extents(trans, inode, cur_offset,
3371 cur_offset + hole_size,
3374 btrfs_update_inode(trans, root, inode);
3375 btrfs_end_transaction(trans, root);
3379 err = btrfs_insert_file_extent(trans, root,
3380 btrfs_ino(inode), cur_offset, 0,
3381 0, hole_size, 0, hole_size,
3384 btrfs_update_inode(trans, root, inode);
3385 btrfs_end_transaction(trans, root);
3389 btrfs_drop_extent_cache(inode, hole_start,
3392 btrfs_update_inode(trans, root, inode);
3393 btrfs_end_transaction(trans, root);
3395 free_extent_map(em);
3397 cur_offset = last_byte;
3398 if (cur_offset >= block_end)
3402 free_extent_map(em);
3403 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state,
3408 static int btrfs_setsize(struct inode *inode, loff_t newsize)
3410 struct btrfs_root *root = BTRFS_I(inode)->root;
3411 struct btrfs_trans_handle *trans;
3412 loff_t oldsize = i_size_read(inode);
3415 if (newsize == oldsize)
3418 if (newsize > oldsize) {
3419 truncate_pagecache(inode, oldsize, newsize);
3420 ret = btrfs_cont_expand(inode, oldsize, newsize);
3424 trans = btrfs_start_transaction(root, 1);
3426 return PTR_ERR(trans);
3428 i_size_write(inode, newsize);
3429 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL);
3430 ret = btrfs_update_inode(trans, root, inode);
3431 btrfs_end_transaction(trans, root);
3435 * We're truncating a file that used to have good data down to
3436 * zero. Make sure it gets into the ordered flush list so that
3437 * any new writes get down to disk quickly.
3440 BTRFS_I(inode)->ordered_data_close = 1;
3442 /* we don't support swapfiles, so vmtruncate shouldn't fail */
3443 truncate_setsize(inode, newsize);
3444 ret = btrfs_truncate(inode);
3450 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
3452 struct inode *inode = dentry->d_inode;
3453 struct btrfs_root *root = BTRFS_I(inode)->root;
3456 if (btrfs_root_readonly(root))
3459 err = inode_change_ok(inode, attr);
3463 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
3464 err = btrfs_setsize(inode, attr->ia_size);
3469 if (attr->ia_valid) {
3470 setattr_copy(inode, attr);
3471 err = btrfs_dirty_inode(inode);
3473 if (!err && attr->ia_valid & ATTR_MODE)
3474 err = btrfs_acl_chmod(inode);
3480 void btrfs_evict_inode(struct inode *inode)
3482 struct btrfs_trans_handle *trans;
3483 struct btrfs_root *root = BTRFS_I(inode)->root;
3484 struct btrfs_block_rsv *rsv, *global_rsv;
3485 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
3489 trace_btrfs_inode_evict(inode);
3491 truncate_inode_pages(&inode->i_data, 0);
3492 if (inode->i_nlink && (btrfs_root_refs(&root->root_item) != 0 ||
3493 btrfs_is_free_space_inode(root, inode)))
3496 if (is_bad_inode(inode)) {
3497 btrfs_orphan_del(NULL, inode);
3500 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */
3501 btrfs_wait_ordered_range(inode, 0, (u64)-1);
3503 if (root->fs_info->log_root_recovering) {
3504 BUG_ON(!list_empty(&BTRFS_I(inode)->i_orphan));
3508 if (inode->i_nlink > 0) {
3509 BUG_ON(btrfs_root_refs(&root->root_item) != 0);
3513 rsv = btrfs_alloc_block_rsv(root);
3515 btrfs_orphan_del(NULL, inode);
3518 rsv->size = min_size;
3519 global_rsv = &root->fs_info->global_block_rsv;
3521 btrfs_i_size_write(inode, 0);
3524 * This is a bit simpler than btrfs_truncate since
3526 * 1) We've already reserved our space for our orphan item in the
3528 * 2) We're going to delete the inode item, so we don't need to update
3531 * So we just need to reserve some slack space in case we add bytes when
3532 * doing the truncate.
3535 ret = btrfs_block_rsv_refill_noflush(root, rsv, min_size);
3538 * Try and steal from the global reserve since we will
3539 * likely not use this space anyway, we want to try as
3540 * hard as possible to get this to work.
3543 ret = btrfs_block_rsv_migrate(global_rsv, rsv, min_size);
3546 printk(KERN_WARNING "Could not get space for a "
3547 "delete, will truncate on mount %d\n", ret);
3548 btrfs_orphan_del(NULL, inode);
3549 btrfs_free_block_rsv(root, rsv);
3553 trans = btrfs_start_transaction(root, 0);
3554 if (IS_ERR(trans)) {
3555 btrfs_orphan_del(NULL, inode);
3556 btrfs_free_block_rsv(root, rsv);
3560 trans->block_rsv = rsv;
3562 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
3566 nr = trans->blocks_used;
3567 btrfs_end_transaction(trans, root);
3569 btrfs_btree_balance_dirty(root, nr);
3572 btrfs_free_block_rsv(root, rsv);
3575 trans->block_rsv = root->orphan_block_rsv;
3576 ret = btrfs_orphan_del(trans, inode);
3580 trans->block_rsv = &root->fs_info->trans_block_rsv;
3581 if (!(root == root->fs_info->tree_root ||
3582 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
3583 btrfs_return_ino(root, btrfs_ino(inode));
3585 nr = trans->blocks_used;
3586 btrfs_end_transaction(trans, root);
3587 btrfs_btree_balance_dirty(root, nr);
3589 end_writeback(inode);
3594 * this returns the key found in the dir entry in the location pointer.
3595 * If no dir entries were found, location->objectid is 0.
3597 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
3598 struct btrfs_key *location)
3600 const char *name = dentry->d_name.name;
3601 int namelen = dentry->d_name.len;
3602 struct btrfs_dir_item *di;
3603 struct btrfs_path *path;
3604 struct btrfs_root *root = BTRFS_I(dir)->root;
3607 path = btrfs_alloc_path();
3611 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir), name,
3616 if (IS_ERR_OR_NULL(di))
3619 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
3621 btrfs_free_path(path);
3624 location->objectid = 0;
3629 * when we hit a tree root in a directory, the btrfs part of the inode
3630 * needs to be changed to reflect the root directory of the tree root. This
3631 * is kind of like crossing a mount point.
3633 static int fixup_tree_root_location(struct btrfs_root *root,
3635 struct dentry *dentry,
3636 struct btrfs_key *location,
3637 struct btrfs_root **sub_root)
3639 struct btrfs_path *path;
3640 struct btrfs_root *new_root;
3641 struct btrfs_root_ref *ref;
3642 struct extent_buffer *leaf;
3646 path = btrfs_alloc_path();
3653 ret = btrfs_find_root_ref(root->fs_info->tree_root, path,
3654 BTRFS_I(dir)->root->root_key.objectid,
3655 location->objectid);
3662 leaf = path->nodes[0];
3663 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
3664 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(dir) ||
3665 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
3668 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
3669 (unsigned long)(ref + 1),
3670 dentry->d_name.len);
3674 btrfs_release_path(path);
3676 new_root = btrfs_read_fs_root_no_name(root->fs_info, location);
3677 if (IS_ERR(new_root)) {
3678 err = PTR_ERR(new_root);
3682 if (btrfs_root_refs(&new_root->root_item) == 0) {
3687 *sub_root = new_root;
3688 location->objectid = btrfs_root_dirid(&new_root->root_item);
3689 location->type = BTRFS_INODE_ITEM_KEY;
3690 location->offset = 0;
3693 btrfs_free_path(path);
3697 static void inode_tree_add(struct inode *inode)
3699 struct btrfs_root *root = BTRFS_I(inode)->root;
3700 struct btrfs_inode *entry;
3702 struct rb_node *parent;
3703 u64 ino = btrfs_ino(inode);
3705 p = &root->inode_tree.rb_node;
3708 if (inode_unhashed(inode))
3711 spin_lock(&root->inode_lock);
3714 entry = rb_entry(parent, struct btrfs_inode, rb_node);
3716 if (ino < btrfs_ino(&entry->vfs_inode))
3717 p = &parent->rb_left;
3718 else if (ino > btrfs_ino(&entry->vfs_inode))
3719 p = &parent->rb_right;
3721 WARN_ON(!(entry->vfs_inode.i_state &
3722 (I_WILL_FREE | I_FREEING)));
3723 rb_erase(parent, &root->inode_tree);
3724 RB_CLEAR_NODE(parent);
3725 spin_unlock(&root->inode_lock);
3729 rb_link_node(&BTRFS_I(inode)->rb_node, parent, p);
3730 rb_insert_color(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3731 spin_unlock(&root->inode_lock);
3734 static void inode_tree_del(struct inode *inode)
3736 struct btrfs_root *root = BTRFS_I(inode)->root;
3739 spin_lock(&root->inode_lock);
3740 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
3741 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3742 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
3743 empty = RB_EMPTY_ROOT(&root->inode_tree);
3745 spin_unlock(&root->inode_lock);
3748 * Free space cache has inodes in the tree root, but the tree root has a
3749 * root_refs of 0, so this could end up dropping the tree root as a
3750 * snapshot, so we need the extra !root->fs_info->tree_root check to
3751 * make sure we don't drop it.
3753 if (empty && btrfs_root_refs(&root->root_item) == 0 &&
3754 root != root->fs_info->tree_root) {
3755 synchronize_srcu(&root->fs_info->subvol_srcu);
3756 spin_lock(&root->inode_lock);
3757 empty = RB_EMPTY_ROOT(&root->inode_tree);
3758 spin_unlock(&root->inode_lock);
3760 btrfs_add_dead_root(root);
3764 int btrfs_invalidate_inodes(struct btrfs_root *root)
3766 struct rb_node *node;
3767 struct rb_node *prev;
3768 struct btrfs_inode *entry;
3769 struct inode *inode;
3772 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
3774 spin_lock(&root->inode_lock);
3776 node = root->inode_tree.rb_node;
3780 entry = rb_entry(node, struct btrfs_inode, rb_node);
3782 if (objectid < btrfs_ino(&entry->vfs_inode))
3783 node = node->rb_left;
3784 else if (objectid > btrfs_ino(&entry->vfs_inode))
3785 node = node->rb_right;
3791 entry = rb_entry(prev, struct btrfs_inode, rb_node);
3792 if (objectid <= btrfs_ino(&entry->vfs_inode)) {
3796 prev = rb_next(prev);
3800 entry = rb_entry(node, struct btrfs_inode, rb_node);
3801 objectid = btrfs_ino(&entry->vfs_inode) + 1;
3802 inode = igrab(&entry->vfs_inode);
3804 spin_unlock(&root->inode_lock);
3805 if (atomic_read(&inode->i_count) > 1)
3806 d_prune_aliases(inode);
3808 * btrfs_drop_inode will have it removed from
3809 * the inode cache when its usage count
3814 spin_lock(&root->inode_lock);
3818 if (cond_resched_lock(&root->inode_lock))
3821 node = rb_next(node);
3823 spin_unlock(&root->inode_lock);
3827 static int btrfs_init_locked_inode(struct inode *inode, void *p)
3829 struct btrfs_iget_args *args = p;
3830 inode->i_ino = args->ino;
3831 BTRFS_I(inode)->root = args->root;
3832 btrfs_set_inode_space_info(args->root, inode);
3836 static int btrfs_find_actor(struct inode *inode, void *opaque)
3838 struct btrfs_iget_args *args = opaque;
3839 return args->ino == btrfs_ino(inode) &&
3840 args->root == BTRFS_I(inode)->root;
3843 static struct inode *btrfs_iget_locked(struct super_block *s,
3845 struct btrfs_root *root)
3847 struct inode *inode;
3848 struct btrfs_iget_args args;
3849 args.ino = objectid;
3852 inode = iget5_locked(s, objectid, btrfs_find_actor,
3853 btrfs_init_locked_inode,
3858 /* Get an inode object given its location and corresponding root.
3859 * Returns in *is_new if the inode was read from disk
3861 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
3862 struct btrfs_root *root, int *new)
3864 struct inode *inode;
3866 inode = btrfs_iget_locked(s, location->objectid, root);
3868 return ERR_PTR(-ENOMEM);
3870 if (inode->i_state & I_NEW) {
3871 BTRFS_I(inode)->root = root;
3872 memcpy(&BTRFS_I(inode)->location, location, sizeof(*location));
3873 btrfs_read_locked_inode(inode);
3874 if (!is_bad_inode(inode)) {
3875 inode_tree_add(inode);
3876 unlock_new_inode(inode);
3880 unlock_new_inode(inode);
3882 inode = ERR_PTR(-ESTALE);
3889 static struct inode *new_simple_dir(struct super_block *s,
3890 struct btrfs_key *key,
3891 struct btrfs_root *root)
3893 struct inode *inode = new_inode(s);
3896 return ERR_PTR(-ENOMEM);
3898 BTRFS_I(inode)->root = root;
3899 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
3900 BTRFS_I(inode)->dummy_inode = 1;
3902 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
3903 inode->i_op = &simple_dir_inode_operations;
3904 inode->i_fop = &simple_dir_operations;
3905 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
3906 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
3911 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
3913 struct inode *inode;
3914 struct btrfs_root *root = BTRFS_I(dir)->root;
3915 struct btrfs_root *sub_root = root;
3916 struct btrfs_key location;
3920 if (dentry->d_name.len > BTRFS_NAME_LEN)
3921 return ERR_PTR(-ENAMETOOLONG);
3923 if (unlikely(d_need_lookup(dentry))) {
3924 memcpy(&location, dentry->d_fsdata, sizeof(struct btrfs_key));
3925 kfree(dentry->d_fsdata);
3926 dentry->d_fsdata = NULL;
3927 /* This thing is hashed, drop it for now */
3930 ret = btrfs_inode_by_name(dir, dentry, &location);
3934 return ERR_PTR(ret);
3936 if (location.objectid == 0)
3939 if (location.type == BTRFS_INODE_ITEM_KEY) {
3940 inode = btrfs_iget(dir->i_sb, &location, root, NULL);
3944 BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY);
3946 index = srcu_read_lock(&root->fs_info->subvol_srcu);
3947 ret = fixup_tree_root_location(root, dir, dentry,
3948 &location, &sub_root);
3951 inode = ERR_PTR(ret);
3953 inode = new_simple_dir(dir->i_sb, &location, sub_root);
3955 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL);
3957 srcu_read_unlock(&root->fs_info->subvol_srcu, index);
3959 if (!IS_ERR(inode) && root != sub_root) {
3960 down_read(&root->fs_info->cleanup_work_sem);
3961 if (!(inode->i_sb->s_flags & MS_RDONLY))
3962 ret = btrfs_orphan_cleanup(sub_root);
3963 up_read(&root->fs_info->cleanup_work_sem);
3965 inode = ERR_PTR(ret);
3971 static int btrfs_dentry_delete(const struct dentry *dentry)
3973 struct btrfs_root *root;
3975 if (!dentry->d_inode && !IS_ROOT(dentry))
3976 dentry = dentry->d_parent;
3978 if (dentry->d_inode) {
3979 root = BTRFS_I(dentry->d_inode)->root;
3980 if (btrfs_root_refs(&root->root_item) == 0)
3986 static void btrfs_dentry_release(struct dentry *dentry)
3988 if (dentry->d_fsdata)
3989 kfree(dentry->d_fsdata);
3992 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
3993 struct nameidata *nd)
3997 ret = d_splice_alias(btrfs_lookup_dentry(dir, dentry), dentry);
3998 if (unlikely(d_need_lookup(dentry))) {
3999 spin_lock(&dentry->d_lock);
4000 dentry->d_flags &= ~DCACHE_NEED_LOOKUP;
4001 spin_unlock(&dentry->d_lock);
4006 unsigned char btrfs_filetype_table[] = {
4007 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
4010 static int btrfs_real_readdir(struct file *filp, void *dirent,
4013 struct inode *inode = filp->f_dentry->d_inode;
4014 struct btrfs_root *root = BTRFS_I(inode)->root;
4015 struct btrfs_item *item;
4016 struct btrfs_dir_item *di;
4017 struct btrfs_key key;
4018 struct btrfs_key found_key;
4019 struct btrfs_path *path;
4020 struct list_head ins_list;
4021 struct list_head del_list;
4024 struct extent_buffer *leaf;
4026 unsigned char d_type;
4031 int key_type = BTRFS_DIR_INDEX_KEY;
4035 int is_curr = 0; /* filp->f_pos points to the current index? */
4037 /* FIXME, use a real flag for deciding about the key type */
4038 if (root->fs_info->tree_root == root)
4039 key_type = BTRFS_DIR_ITEM_KEY;
4041 /* special case for "." */
4042 if (filp->f_pos == 0) {
4043 over = filldir(dirent, ".", 1,
4044 filp->f_pos, btrfs_ino(inode), DT_DIR);
4049 /* special case for .., just use the back ref */
4050 if (filp->f_pos == 1) {
4051 u64 pino = parent_ino(filp->f_path.dentry);
4052 over = filldir(dirent, "..", 2,
4053 filp->f_pos, pino, DT_DIR);
4058 path = btrfs_alloc_path();
4064 if (key_type == BTRFS_DIR_INDEX_KEY) {
4065 INIT_LIST_HEAD(&ins_list);
4066 INIT_LIST_HEAD(&del_list);
4067 btrfs_get_delayed_items(inode, &ins_list, &del_list);
4070 btrfs_set_key_type(&key, key_type);
4071 key.offset = filp->f_pos;
4072 key.objectid = btrfs_ino(inode);
4074 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4079 leaf = path->nodes[0];
4080 slot = path->slots[0];
4081 if (slot >= btrfs_header_nritems(leaf)) {
4082 ret = btrfs_next_leaf(root, path);
4090 item = btrfs_item_nr(leaf, slot);
4091 btrfs_item_key_to_cpu(leaf, &found_key, slot);
4093 if (found_key.objectid != key.objectid)
4095 if (btrfs_key_type(&found_key) != key_type)
4097 if (found_key.offset < filp->f_pos)
4099 if (key_type == BTRFS_DIR_INDEX_KEY &&
4100 btrfs_should_delete_dir_index(&del_list,
4104 filp->f_pos = found_key.offset;
4107 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
4109 di_total = btrfs_item_size(leaf, item);
4111 while (di_cur < di_total) {
4112 struct btrfs_key location;
4115 if (verify_dir_item(root, leaf, di))
4118 name_len = btrfs_dir_name_len(leaf, di);
4119 if (name_len <= sizeof(tmp_name)) {
4120 name_ptr = tmp_name;
4122 name_ptr = kmalloc(name_len, GFP_NOFS);
4128 read_extent_buffer(leaf, name_ptr,
4129 (unsigned long)(di + 1), name_len);
4131 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
4132 btrfs_dir_item_key_to_cpu(leaf, di, &location);
4136 q.hash = full_name_hash(q.name, q.len);
4137 tmp = d_lookup(filp->f_dentry, &q);
4139 struct btrfs_key *newkey;
4141 newkey = kzalloc(sizeof(struct btrfs_key),
4145 tmp = d_alloc(filp->f_dentry, &q);
4151 memcpy(newkey, &location,
4152 sizeof(struct btrfs_key));
4153 tmp->d_fsdata = newkey;
4154 tmp->d_flags |= DCACHE_NEED_LOOKUP;
4161 /* is this a reference to our own snapshot? If so
4164 if (location.type == BTRFS_ROOT_ITEM_KEY &&
4165 location.objectid == root->root_key.objectid) {
4169 over = filldir(dirent, name_ptr, name_len,
4170 found_key.offset, location.objectid,
4174 if (name_ptr != tmp_name)
4179 di_len = btrfs_dir_name_len(leaf, di) +
4180 btrfs_dir_data_len(leaf, di) + sizeof(*di);
4182 di = (struct btrfs_dir_item *)((char *)di + di_len);
4188 if (key_type == BTRFS_DIR_INDEX_KEY) {
4191 ret = btrfs_readdir_delayed_dir_index(filp, dirent, filldir,
4197 /* Reached end of directory/root. Bump pos past the last item. */
4198 if (key_type == BTRFS_DIR_INDEX_KEY)
4200 * 32-bit glibc will use getdents64, but then strtol -
4201 * so the last number we can serve is this.
4203 filp->f_pos = 0x7fffffff;
4209 if (key_type == BTRFS_DIR_INDEX_KEY)
4210 btrfs_put_delayed_items(&ins_list, &del_list);
4211 btrfs_free_path(path);
4215 int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc)
4217 struct btrfs_root *root = BTRFS_I(inode)->root;
4218 struct btrfs_trans_handle *trans;
4220 bool nolock = false;
4222 if (BTRFS_I(inode)->dummy_inode)
4225 if (btrfs_fs_closing(root->fs_info) && btrfs_is_free_space_inode(root, inode))
4228 if (wbc->sync_mode == WB_SYNC_ALL) {
4230 trans = btrfs_join_transaction_nolock(root);
4232 trans = btrfs_join_transaction(root);
4234 return PTR_ERR(trans);
4236 ret = btrfs_end_transaction_nolock(trans, root);
4238 ret = btrfs_commit_transaction(trans, root);
4244 * This is somewhat expensive, updating the tree every time the
4245 * inode changes. But, it is most likely to find the inode in cache.
4246 * FIXME, needs more benchmarking...there are no reasons other than performance
4247 * to keep or drop this code.
4249 int btrfs_dirty_inode(struct inode *inode)
4251 struct btrfs_root *root = BTRFS_I(inode)->root;
4252 struct btrfs_trans_handle *trans;
4255 if (BTRFS_I(inode)->dummy_inode)
4258 trans = btrfs_join_transaction(root);
4260 return PTR_ERR(trans);
4262 ret = btrfs_update_inode(trans, root, inode);
4263 if (ret && ret == -ENOSPC) {
4264 /* whoops, lets try again with the full transaction */
4265 btrfs_end_transaction(trans, root);
4266 trans = btrfs_start_transaction(root, 1);
4268 return PTR_ERR(trans);
4270 ret = btrfs_update_inode(trans, root, inode);
4272 btrfs_end_transaction(trans, root);
4273 if (BTRFS_I(inode)->delayed_node)
4274 btrfs_balance_delayed_items(root);
4280 * This is a copy of file_update_time. We need this so we can return error on
4281 * ENOSPC for updating the inode in the case of file write and mmap writes.
4283 int btrfs_update_time(struct file *file)
4285 struct inode *inode = file->f_path.dentry->d_inode;
4286 struct timespec now;
4288 enum { S_MTIME = 1, S_CTIME = 2, S_VERSION = 4 } sync_it = 0;
4290 /* First try to exhaust all avenues to not sync */
4291 if (IS_NOCMTIME(inode))
4294 now = current_fs_time(inode->i_sb);
4295 if (!timespec_equal(&inode->i_mtime, &now))
4298 if (!timespec_equal(&inode->i_ctime, &now))
4301 if (IS_I_VERSION(inode))
4302 sync_it |= S_VERSION;
4307 /* Finally allowed to write? Takes lock. */
4308 if (mnt_want_write_file(file))
4311 /* Only change inode inside the lock region */
4312 if (sync_it & S_VERSION)
4313 inode_inc_iversion(inode);
4314 if (sync_it & S_CTIME)
4315 inode->i_ctime = now;
4316 if (sync_it & S_MTIME)
4317 inode->i_mtime = now;
4318 ret = btrfs_dirty_inode(inode);
4320 mark_inode_dirty_sync(inode);
4321 mnt_drop_write(file->f_path.mnt);
4326 * find the highest existing sequence number in a directory
4327 * and then set the in-memory index_cnt variable to reflect
4328 * free sequence numbers
4330 static int btrfs_set_inode_index_count(struct inode *inode)
4332 struct btrfs_root *root = BTRFS_I(inode)->root;
4333 struct btrfs_key key, found_key;
4334 struct btrfs_path *path;
4335 struct extent_buffer *leaf;
4338 key.objectid = btrfs_ino(inode);
4339 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
4340 key.offset = (u64)-1;
4342 path = btrfs_alloc_path();
4346 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4349 /* FIXME: we should be able to handle this */
4355 * MAGIC NUMBER EXPLANATION:
4356 * since we search a directory based on f_pos we have to start at 2
4357 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
4358 * else has to start at 2
4360 if (path->slots[0] == 0) {
4361 BTRFS_I(inode)->index_cnt = 2;
4367 leaf = path->nodes[0];
4368 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4370 if (found_key.objectid != btrfs_ino(inode) ||
4371 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
4372 BTRFS_I(inode)->index_cnt = 2;
4376 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
4378 btrfs_free_path(path);
4383 * helper to find a free sequence number in a given directory. This current
4384 * code is very simple, later versions will do smarter things in the btree
4386 int btrfs_set_inode_index(struct inode *dir, u64 *index)
4390 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
4391 ret = btrfs_inode_delayed_dir_index_count(dir);
4393 ret = btrfs_set_inode_index_count(dir);
4399 *index = BTRFS_I(dir)->index_cnt;
4400 BTRFS_I(dir)->index_cnt++;
4405 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
4406 struct btrfs_root *root,
4408 const char *name, int name_len,
4409 u64 ref_objectid, u64 objectid, int mode,
4412 struct inode *inode;
4413 struct btrfs_inode_item *inode_item;
4414 struct btrfs_key *location;
4415 struct btrfs_path *path;
4416 struct btrfs_inode_ref *ref;
4417 struct btrfs_key key[2];
4423 path = btrfs_alloc_path();
4425 return ERR_PTR(-ENOMEM);
4427 inode = new_inode(root->fs_info->sb);
4429 btrfs_free_path(path);
4430 return ERR_PTR(-ENOMEM);
4434 * we have to initialize this early, so we can reclaim the inode
4435 * number if we fail afterwards in this function.
4437 inode->i_ino = objectid;
4440 trace_btrfs_inode_request(dir);
4442 ret = btrfs_set_inode_index(dir, index);
4444 btrfs_free_path(path);
4446 return ERR_PTR(ret);
4450 * index_cnt is ignored for everything but a dir,
4451 * btrfs_get_inode_index_count has an explanation for the magic
4454 BTRFS_I(inode)->index_cnt = 2;
4455 BTRFS_I(inode)->root = root;
4456 BTRFS_I(inode)->generation = trans->transid;
4457 inode->i_generation = BTRFS_I(inode)->generation;
4458 btrfs_set_inode_space_info(root, inode);
4465 key[0].objectid = objectid;
4466 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
4469 key[1].objectid = objectid;
4470 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
4471 key[1].offset = ref_objectid;
4473 sizes[0] = sizeof(struct btrfs_inode_item);
4474 sizes[1] = name_len + sizeof(*ref);
4476 path->leave_spinning = 1;
4477 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
4481 inode_init_owner(inode, dir, mode);
4482 inode_set_bytes(inode, 0);
4483 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
4484 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
4485 struct btrfs_inode_item);
4486 fill_inode_item(trans, path->nodes[0], inode_item, inode);
4488 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
4489 struct btrfs_inode_ref);
4490 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
4491 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
4492 ptr = (unsigned long)(ref + 1);
4493 write_extent_buffer(path->nodes[0], name, ptr, name_len);
4495 btrfs_mark_buffer_dirty(path->nodes[0]);
4496 btrfs_free_path(path);
4498 location = &BTRFS_I(inode)->location;
4499 location->objectid = objectid;
4500 location->offset = 0;
4501 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
4503 btrfs_inherit_iflags(inode, dir);
4505 if (S_ISREG(mode)) {
4506 if (btrfs_test_opt(root, NODATASUM))
4507 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
4508 if (btrfs_test_opt(root, NODATACOW) ||
4509 (BTRFS_I(dir)->flags & BTRFS_INODE_NODATACOW))
4510 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
4513 insert_inode_hash(inode);
4514 inode_tree_add(inode);
4516 trace_btrfs_inode_new(inode);
4517 btrfs_set_inode_last_trans(trans, inode);
4522 BTRFS_I(dir)->index_cnt--;
4523 btrfs_free_path(path);
4525 return ERR_PTR(ret);
4528 static inline u8 btrfs_inode_type(struct inode *inode)
4530 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
4534 * utility function to add 'inode' into 'parent_inode' with
4535 * a give name and a given sequence number.
4536 * if 'add_backref' is true, also insert a backref from the
4537 * inode to the parent directory.
4539 int btrfs_add_link(struct btrfs_trans_handle *trans,
4540 struct inode *parent_inode, struct inode *inode,
4541 const char *name, int name_len, int add_backref, u64 index)
4544 struct btrfs_key key;
4545 struct btrfs_root *root = BTRFS_I(parent_inode)->root;
4546 u64 ino = btrfs_ino(inode);
4547 u64 parent_ino = btrfs_ino(parent_inode);
4549 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
4550 memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key));
4553 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
4557 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
4558 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
4559 key.objectid, root->root_key.objectid,
4560 parent_ino, index, name, name_len);
4561 } else if (add_backref) {
4562 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino,
4567 ret = btrfs_insert_dir_item(trans, root, name, name_len,
4569 btrfs_inode_type(inode), index);
4572 btrfs_i_size_write(parent_inode, parent_inode->i_size +
4574 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
4575 ret = btrfs_update_inode(trans, root, parent_inode);
4580 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
4581 struct inode *dir, struct dentry *dentry,
4582 struct inode *inode, int backref, u64 index)
4584 int err = btrfs_add_link(trans, dir, inode,
4585 dentry->d_name.name, dentry->d_name.len,
4592 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
4593 int mode, dev_t rdev)
4595 struct btrfs_trans_handle *trans;
4596 struct btrfs_root *root = BTRFS_I(dir)->root;
4597 struct inode *inode = NULL;
4601 unsigned long nr = 0;
4604 if (!new_valid_dev(rdev))
4608 * 2 for inode item and ref
4610 * 1 for xattr if selinux is on
4612 trans = btrfs_start_transaction(root, 5);
4614 return PTR_ERR(trans);
4616 err = btrfs_find_free_ino(root, &objectid);
4620 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4621 dentry->d_name.len, btrfs_ino(dir), objectid,
4623 if (IS_ERR(inode)) {
4624 err = PTR_ERR(inode);
4628 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4635 * If the active LSM wants to access the inode during
4636 * d_instantiate it needs these. Smack checks to see
4637 * if the filesystem supports xattrs by looking at the
4641 inode->i_op = &btrfs_special_inode_operations;
4642 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
4646 init_special_inode(inode, inode->i_mode, rdev);
4647 btrfs_update_inode(trans, root, inode);
4648 d_instantiate(dentry, inode);
4651 nr = trans->blocks_used;
4652 btrfs_end_transaction(trans, root);
4653 btrfs_btree_balance_dirty(root, nr);
4655 inode_dec_link_count(inode);
4661 static int btrfs_create(struct inode *dir, struct dentry *dentry,
4662 int mode, struct nameidata *nd)
4664 struct btrfs_trans_handle *trans;
4665 struct btrfs_root *root = BTRFS_I(dir)->root;
4666 struct inode *inode = NULL;
4669 unsigned long nr = 0;
4674 * 2 for inode item and ref
4676 * 1 for xattr if selinux is on
4678 trans = btrfs_start_transaction(root, 5);
4680 return PTR_ERR(trans);
4682 err = btrfs_find_free_ino(root, &objectid);
4686 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4687 dentry->d_name.len, btrfs_ino(dir), objectid,
4689 if (IS_ERR(inode)) {
4690 err = PTR_ERR(inode);
4694 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4701 * If the active LSM wants to access the inode during
4702 * d_instantiate it needs these. Smack checks to see
4703 * if the filesystem supports xattrs by looking at the
4706 inode->i_fop = &btrfs_file_operations;
4707 inode->i_op = &btrfs_file_inode_operations;
4709 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
4713 inode->i_mapping->a_ops = &btrfs_aops;
4714 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
4715 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
4716 d_instantiate(dentry, inode);
4719 nr = trans->blocks_used;
4720 btrfs_end_transaction(trans, root);
4722 inode_dec_link_count(inode);
4725 btrfs_btree_balance_dirty(root, nr);
4729 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
4730 struct dentry *dentry)
4732 struct btrfs_trans_handle *trans;
4733 struct btrfs_root *root = BTRFS_I(dir)->root;
4734 struct inode *inode = old_dentry->d_inode;
4736 unsigned long nr = 0;
4740 /* do not allow sys_link's with other subvols of the same device */
4741 if (root->objectid != BTRFS_I(inode)->root->objectid)
4744 if (inode->i_nlink == ~0U)
4747 err = btrfs_set_inode_index(dir, &index);
4752 * 2 items for inode and inode ref
4753 * 2 items for dir items
4754 * 1 item for parent inode
4756 trans = btrfs_start_transaction(root, 5);
4757 if (IS_ERR(trans)) {
4758 err = PTR_ERR(trans);
4762 btrfs_inc_nlink(inode);
4763 inode->i_ctime = CURRENT_TIME;
4766 err = btrfs_add_nondir(trans, dir, dentry, inode, 1, index);
4771 struct dentry *parent = dentry->d_parent;
4772 err = btrfs_update_inode(trans, root, inode);
4774 d_instantiate(dentry, inode);
4775 btrfs_log_new_name(trans, inode, NULL, parent);
4778 nr = trans->blocks_used;
4779 btrfs_end_transaction(trans, root);
4782 inode_dec_link_count(inode);
4785 btrfs_btree_balance_dirty(root, nr);
4789 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
4791 struct inode *inode = NULL;
4792 struct btrfs_trans_handle *trans;
4793 struct btrfs_root *root = BTRFS_I(dir)->root;
4795 int drop_on_err = 0;
4798 unsigned long nr = 1;
4801 * 2 items for inode and ref
4802 * 2 items for dir items
4803 * 1 for xattr if selinux is on
4805 trans = btrfs_start_transaction(root, 5);
4807 return PTR_ERR(trans);
4809 err = btrfs_find_free_ino(root, &objectid);
4813 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4814 dentry->d_name.len, btrfs_ino(dir), objectid,
4815 S_IFDIR | mode, &index);
4816 if (IS_ERR(inode)) {
4817 err = PTR_ERR(inode);
4823 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4827 inode->i_op = &btrfs_dir_inode_operations;
4828 inode->i_fop = &btrfs_dir_file_operations;
4830 btrfs_i_size_write(inode, 0);
4831 err = btrfs_update_inode(trans, root, inode);
4835 err = btrfs_add_link(trans, dir, inode, dentry->d_name.name,
4836 dentry->d_name.len, 0, index);
4840 d_instantiate(dentry, inode);
4844 nr = trans->blocks_used;
4845 btrfs_end_transaction(trans, root);
4848 btrfs_btree_balance_dirty(root, nr);
4852 /* helper for btfs_get_extent. Given an existing extent in the tree,
4853 * and an extent that you want to insert, deal with overlap and insert
4854 * the new extent into the tree.
4856 static int merge_extent_mapping(struct extent_map_tree *em_tree,
4857 struct extent_map *existing,
4858 struct extent_map *em,
4859 u64 map_start, u64 map_len)
4863 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
4864 start_diff = map_start - em->start;
4865 em->start = map_start;
4867 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
4868 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
4869 em->block_start += start_diff;
4870 em->block_len -= start_diff;
4872 return add_extent_mapping(em_tree, em);
4875 static noinline int uncompress_inline(struct btrfs_path *path,
4876 struct inode *inode, struct page *page,
4877 size_t pg_offset, u64 extent_offset,
4878 struct btrfs_file_extent_item *item)
4881 struct extent_buffer *leaf = path->nodes[0];
4884 unsigned long inline_size;
4888 WARN_ON(pg_offset != 0);
4889 compress_type = btrfs_file_extent_compression(leaf, item);
4890 max_size = btrfs_file_extent_ram_bytes(leaf, item);
4891 inline_size = btrfs_file_extent_inline_item_len(leaf,
4892 btrfs_item_nr(leaf, path->slots[0]));
4893 tmp = kmalloc(inline_size, GFP_NOFS);
4896 ptr = btrfs_file_extent_inline_start(item);
4898 read_extent_buffer(leaf, tmp, ptr, inline_size);
4900 max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size);
4901 ret = btrfs_decompress(compress_type, tmp, page,
4902 extent_offset, inline_size, max_size);
4904 char *kaddr = kmap_atomic(page, KM_USER0);
4905 unsigned long copy_size = min_t(u64,
4906 PAGE_CACHE_SIZE - pg_offset,
4907 max_size - extent_offset);
4908 memset(kaddr + pg_offset, 0, copy_size);
4909 kunmap_atomic(kaddr, KM_USER0);
4916 * a bit scary, this does extent mapping from logical file offset to the disk.
4917 * the ugly parts come from merging extents from the disk with the in-ram
4918 * representation. This gets more complex because of the data=ordered code,
4919 * where the in-ram extents might be locked pending data=ordered completion.
4921 * This also copies inline extents directly into the page.
4924 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
4925 size_t pg_offset, u64 start, u64 len,
4931 u64 extent_start = 0;
4933 u64 objectid = btrfs_ino(inode);
4935 struct btrfs_path *path = NULL;
4936 struct btrfs_root *root = BTRFS_I(inode)->root;
4937 struct btrfs_file_extent_item *item;
4938 struct extent_buffer *leaf;
4939 struct btrfs_key found_key;
4940 struct extent_map *em = NULL;
4941 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
4942 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4943 struct btrfs_trans_handle *trans = NULL;
4947 read_lock(&em_tree->lock);
4948 em = lookup_extent_mapping(em_tree, start, len);
4950 em->bdev = root->fs_info->fs_devices->latest_bdev;
4951 read_unlock(&em_tree->lock);
4954 if (em->start > start || em->start + em->len <= start)
4955 free_extent_map(em);
4956 else if (em->block_start == EXTENT_MAP_INLINE && page)
4957 free_extent_map(em);
4961 em = alloc_extent_map();
4966 em->bdev = root->fs_info->fs_devices->latest_bdev;
4967 em->start = EXTENT_MAP_HOLE;
4968 em->orig_start = EXTENT_MAP_HOLE;
4970 em->block_len = (u64)-1;
4973 path = btrfs_alloc_path();
4979 * Chances are we'll be called again, so go ahead and do
4985 ret = btrfs_lookup_file_extent(trans, root, path,
4986 objectid, start, trans != NULL);
4993 if (path->slots[0] == 0)
4998 leaf = path->nodes[0];
4999 item = btrfs_item_ptr(leaf, path->slots[0],
5000 struct btrfs_file_extent_item);
5001 /* are we inside the extent that was found? */
5002 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5003 found_type = btrfs_key_type(&found_key);
5004 if (found_key.objectid != objectid ||
5005 found_type != BTRFS_EXTENT_DATA_KEY) {
5009 found_type = btrfs_file_extent_type(leaf, item);
5010 extent_start = found_key.offset;
5011 compress_type = btrfs_file_extent_compression(leaf, item);
5012 if (found_type == BTRFS_FILE_EXTENT_REG ||
5013 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
5014 extent_end = extent_start +
5015 btrfs_file_extent_num_bytes(leaf, item);
5016 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
5018 size = btrfs_file_extent_inline_len(leaf, item);
5019 extent_end = (extent_start + size + root->sectorsize - 1) &
5020 ~((u64)root->sectorsize - 1);
5023 if (start >= extent_end) {
5025 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
5026 ret = btrfs_next_leaf(root, path);
5033 leaf = path->nodes[0];
5035 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5036 if (found_key.objectid != objectid ||
5037 found_key.type != BTRFS_EXTENT_DATA_KEY)
5039 if (start + len <= found_key.offset)
5042 em->len = found_key.offset - start;
5046 if (found_type == BTRFS_FILE_EXTENT_REG ||
5047 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
5048 em->start = extent_start;
5049 em->len = extent_end - extent_start;
5050 em->orig_start = extent_start -
5051 btrfs_file_extent_offset(leaf, item);
5052 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
5054 em->block_start = EXTENT_MAP_HOLE;
5057 if (compress_type != BTRFS_COMPRESS_NONE) {
5058 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
5059 em->compress_type = compress_type;
5060 em->block_start = bytenr;
5061 em->block_len = btrfs_file_extent_disk_num_bytes(leaf,
5064 bytenr += btrfs_file_extent_offset(leaf, item);
5065 em->block_start = bytenr;
5066 em->block_len = em->len;
5067 if (found_type == BTRFS_FILE_EXTENT_PREALLOC)
5068 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
5071 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
5075 size_t extent_offset;
5078 em->block_start = EXTENT_MAP_INLINE;
5079 if (!page || create) {
5080 em->start = extent_start;
5081 em->len = extent_end - extent_start;
5085 size = btrfs_file_extent_inline_len(leaf, item);
5086 extent_offset = page_offset(page) + pg_offset - extent_start;
5087 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
5088 size - extent_offset);
5089 em->start = extent_start + extent_offset;
5090 em->len = (copy_size + root->sectorsize - 1) &
5091 ~((u64)root->sectorsize - 1);
5092 em->orig_start = EXTENT_MAP_INLINE;
5093 if (compress_type) {
5094 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
5095 em->compress_type = compress_type;
5097 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
5098 if (create == 0 && !PageUptodate(page)) {
5099 if (btrfs_file_extent_compression(leaf, item) !=
5100 BTRFS_COMPRESS_NONE) {
5101 ret = uncompress_inline(path, inode, page,
5103 extent_offset, item);
5107 read_extent_buffer(leaf, map + pg_offset, ptr,
5109 if (pg_offset + copy_size < PAGE_CACHE_SIZE) {
5110 memset(map + pg_offset + copy_size, 0,
5111 PAGE_CACHE_SIZE - pg_offset -
5116 flush_dcache_page(page);
5117 } else if (create && PageUptodate(page)) {
5121 free_extent_map(em);
5124 btrfs_release_path(path);
5125 trans = btrfs_join_transaction(root);
5128 return ERR_CAST(trans);
5132 write_extent_buffer(leaf, map + pg_offset, ptr,
5135 btrfs_mark_buffer_dirty(leaf);
5137 set_extent_uptodate(io_tree, em->start,
5138 extent_map_end(em) - 1, NULL, GFP_NOFS);
5141 printk(KERN_ERR "btrfs unknown found_type %d\n", found_type);
5148 em->block_start = EXTENT_MAP_HOLE;
5149 set_bit(EXTENT_FLAG_VACANCY, &em->flags);
5151 btrfs_release_path(path);
5152 if (em->start > start || extent_map_end(em) <= start) {
5153 printk(KERN_ERR "Btrfs: bad extent! em: [%llu %llu] passed "
5154 "[%llu %llu]\n", (unsigned long long)em->start,
5155 (unsigned long long)em->len,
5156 (unsigned long long)start,
5157 (unsigned long long)len);
5163 write_lock(&em_tree->lock);
5164 ret = add_extent_mapping(em_tree, em);
5165 /* it is possible that someone inserted the extent into the tree
5166 * while we had the lock dropped. It is also possible that
5167 * an overlapping map exists in the tree
5169 if (ret == -EEXIST) {
5170 struct extent_map *existing;
5174 existing = lookup_extent_mapping(em_tree, start, len);
5175 if (existing && (existing->start > start ||
5176 existing->start + existing->len <= start)) {
5177 free_extent_map(existing);
5181 existing = lookup_extent_mapping(em_tree, em->start,
5184 err = merge_extent_mapping(em_tree, existing,
5187 free_extent_map(existing);
5189 free_extent_map(em);
5194 free_extent_map(em);
5198 free_extent_map(em);
5203 write_unlock(&em_tree->lock);
5206 trace_btrfs_get_extent(root, em);
5209 btrfs_free_path(path);
5211 ret = btrfs_end_transaction(trans, root);
5216 free_extent_map(em);
5217 return ERR_PTR(err);
5222 struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page,
5223 size_t pg_offset, u64 start, u64 len,
5226 struct extent_map *em;
5227 struct extent_map *hole_em = NULL;
5228 u64 range_start = start;
5234 em = btrfs_get_extent(inode, page, pg_offset, start, len, create);
5239 * if our em maps to a hole, there might
5240 * actually be delalloc bytes behind it
5242 if (em->block_start != EXTENT_MAP_HOLE)
5248 /* check to see if we've wrapped (len == -1 or similar) */
5257 /* ok, we didn't find anything, lets look for delalloc */
5258 found = count_range_bits(&BTRFS_I(inode)->io_tree, &range_start,
5259 end, len, EXTENT_DELALLOC, 1);
5260 found_end = range_start + found;
5261 if (found_end < range_start)
5262 found_end = (u64)-1;
5265 * we didn't find anything useful, return
5266 * the original results from get_extent()
5268 if (range_start > end || found_end <= start) {
5274 /* adjust the range_start to make sure it doesn't
5275 * go backwards from the start they passed in
5277 range_start = max(start,range_start);
5278 found = found_end - range_start;
5281 u64 hole_start = start;
5284 em = alloc_extent_map();
5290 * when btrfs_get_extent can't find anything it
5291 * returns one huge hole
5293 * make sure what it found really fits our range, and
5294 * adjust to make sure it is based on the start from
5298 u64 calc_end = extent_map_end(hole_em);
5300 if (calc_end <= start || (hole_em->start > end)) {
5301 free_extent_map(hole_em);
5304 hole_start = max(hole_em->start, start);
5305 hole_len = calc_end - hole_start;
5309 if (hole_em && range_start > hole_start) {
5310 /* our hole starts before our delalloc, so we
5311 * have to return just the parts of the hole
5312 * that go until the delalloc starts
5314 em->len = min(hole_len,
5315 range_start - hole_start);
5316 em->start = hole_start;
5317 em->orig_start = hole_start;
5319 * don't adjust block start at all,
5320 * it is fixed at EXTENT_MAP_HOLE
5322 em->block_start = hole_em->block_start;
5323 em->block_len = hole_len;
5325 em->start = range_start;
5327 em->orig_start = range_start;
5328 em->block_start = EXTENT_MAP_DELALLOC;
5329 em->block_len = found;
5331 } else if (hole_em) {
5336 free_extent_map(hole_em);
5338 free_extent_map(em);
5339 return ERR_PTR(err);
5344 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
5345 struct extent_map *em,
5348 struct btrfs_root *root = BTRFS_I(inode)->root;
5349 struct btrfs_trans_handle *trans;
5350 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
5351 struct btrfs_key ins;
5354 bool insert = false;
5357 * Ok if the extent map we looked up is a hole and is for the exact
5358 * range we want, there is no reason to allocate a new one, however if
5359 * it is not right then we need to free this one and drop the cache for
5362 if (em->block_start != EXTENT_MAP_HOLE || em->start != start ||
5364 free_extent_map(em);
5367 btrfs_drop_extent_cache(inode, start, start + len - 1, 0);
5370 trans = btrfs_join_transaction(root);
5372 return ERR_CAST(trans);
5374 if (start <= BTRFS_I(inode)->disk_i_size && len < 64 * 1024)
5375 btrfs_add_inode_defrag(trans, inode);
5377 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
5379 alloc_hint = get_extent_allocation_hint(inode, start, len);
5380 ret = btrfs_reserve_extent(trans, root, len, root->sectorsize, 0,
5381 alloc_hint, (u64)-1, &ins, 1);
5388 em = alloc_extent_map();
5390 em = ERR_PTR(-ENOMEM);
5396 em->orig_start = em->start;
5397 em->len = ins.offset;
5399 em->block_start = ins.objectid;
5400 em->block_len = ins.offset;
5401 em->bdev = root->fs_info->fs_devices->latest_bdev;
5404 * We need to do this because if we're using the original em we searched
5405 * for, we could have EXTENT_FLAG_VACANCY set, and we don't want that.
5408 set_bit(EXTENT_FLAG_PINNED, &em->flags);
5411 write_lock(&em_tree->lock);
5412 ret = add_extent_mapping(em_tree, em);
5413 write_unlock(&em_tree->lock);
5416 btrfs_drop_extent_cache(inode, start, start + em->len - 1, 0);
5419 ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
5420 ins.offset, ins.offset, 0);
5422 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
5426 btrfs_end_transaction(trans, root);
5431 * returns 1 when the nocow is safe, < 1 on error, 0 if the
5432 * block must be cow'd
5434 static noinline int can_nocow_odirect(struct btrfs_trans_handle *trans,
5435 struct inode *inode, u64 offset, u64 len)
5437 struct btrfs_path *path;
5439 struct extent_buffer *leaf;
5440 struct btrfs_root *root = BTRFS_I(inode)->root;
5441 struct btrfs_file_extent_item *fi;
5442 struct btrfs_key key;
5450 path = btrfs_alloc_path();
5454 ret = btrfs_lookup_file_extent(trans, root, path, btrfs_ino(inode),
5459 slot = path->slots[0];
5462 /* can't find the item, must cow */
5469 leaf = path->nodes[0];
5470 btrfs_item_key_to_cpu(leaf, &key, slot);
5471 if (key.objectid != btrfs_ino(inode) ||
5472 key.type != BTRFS_EXTENT_DATA_KEY) {
5473 /* not our file or wrong item type, must cow */
5477 if (key.offset > offset) {
5478 /* Wrong offset, must cow */
5482 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
5483 found_type = btrfs_file_extent_type(leaf, fi);
5484 if (found_type != BTRFS_FILE_EXTENT_REG &&
5485 found_type != BTRFS_FILE_EXTENT_PREALLOC) {
5486 /* not a regular extent, must cow */
5489 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
5490 backref_offset = btrfs_file_extent_offset(leaf, fi);
5492 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
5493 if (extent_end < offset + len) {
5494 /* extent doesn't include our full range, must cow */
5498 if (btrfs_extent_readonly(root, disk_bytenr))
5502 * look for other files referencing this extent, if we
5503 * find any we must cow
5505 if (btrfs_cross_ref_exist(trans, root, btrfs_ino(inode),
5506 key.offset - backref_offset, disk_bytenr))
5510 * adjust disk_bytenr and num_bytes to cover just the bytes
5511 * in this extent we are about to write. If there
5512 * are any csums in that range we have to cow in order
5513 * to keep the csums correct
5515 disk_bytenr += backref_offset;
5516 disk_bytenr += offset - key.offset;
5517 num_bytes = min(offset + len, extent_end) - offset;
5518 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
5521 * all of the above have passed, it is safe to overwrite this extent
5526 btrfs_free_path(path);
5530 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
5531 struct buffer_head *bh_result, int create)
5533 struct extent_map *em;
5534 struct btrfs_root *root = BTRFS_I(inode)->root;
5535 u64 start = iblock << inode->i_blkbits;
5536 u64 len = bh_result->b_size;
5537 struct btrfs_trans_handle *trans;
5539 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
5544 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered
5545 * io. INLINE is special, and we could probably kludge it in here, but
5546 * it's still buffered so for safety lets just fall back to the generic
5549 * For COMPRESSED we _have_ to read the entire extent in so we can
5550 * decompress it, so there will be buffering required no matter what we
5551 * do, so go ahead and fallback to buffered.
5553 * We return -ENOTBLK because thats what makes DIO go ahead and go back
5554 * to buffered IO. Don't blame me, this is the price we pay for using
5557 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
5558 em->block_start == EXTENT_MAP_INLINE) {
5559 free_extent_map(em);
5563 /* Just a good old fashioned hole, return */
5564 if (!create && (em->block_start == EXTENT_MAP_HOLE ||
5565 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
5566 free_extent_map(em);
5567 /* DIO will do one hole at a time, so just unlock a sector */
5568 unlock_extent(&BTRFS_I(inode)->io_tree, start,
5569 start + root->sectorsize - 1, GFP_NOFS);
5574 * We don't allocate a new extent in the following cases
5576 * 1) The inode is marked as NODATACOW. In this case we'll just use the
5578 * 2) The extent is marked as PREALLOC. We're good to go here and can
5579 * just use the extent.
5583 len = em->len - (start - em->start);
5587 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
5588 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
5589 em->block_start != EXTENT_MAP_HOLE)) {
5594 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
5595 type = BTRFS_ORDERED_PREALLOC;
5597 type = BTRFS_ORDERED_NOCOW;
5598 len = min(len, em->len - (start - em->start));
5599 block_start = em->block_start + (start - em->start);
5602 * we're not going to log anything, but we do need
5603 * to make sure the current transaction stays open
5604 * while we look for nocow cross refs
5606 trans = btrfs_join_transaction(root);
5610 if (can_nocow_odirect(trans, inode, start, len) == 1) {
5611 ret = btrfs_add_ordered_extent_dio(inode, start,
5612 block_start, len, len, type);
5613 btrfs_end_transaction(trans, root);
5615 free_extent_map(em);
5620 btrfs_end_transaction(trans, root);
5624 * this will cow the extent, reset the len in case we changed
5627 len = bh_result->b_size;
5628 em = btrfs_new_extent_direct(inode, em, start, len);
5631 len = min(len, em->len - (start - em->start));
5633 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, start + len - 1,
5634 EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DIRTY, 1,
5637 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
5639 bh_result->b_size = len;
5640 bh_result->b_bdev = em->bdev;
5641 set_buffer_mapped(bh_result);
5642 if (create && !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
5643 set_buffer_new(bh_result);
5645 free_extent_map(em);
5650 struct btrfs_dio_private {
5651 struct inode *inode;
5658 /* number of bios pending for this dio */
5659 atomic_t pending_bios;
5664 struct bio *orig_bio;
5667 static void btrfs_endio_direct_read(struct bio *bio, int err)
5669 struct btrfs_dio_private *dip = bio->bi_private;
5670 struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
5671 struct bio_vec *bvec = bio->bi_io_vec;
5672 struct inode *inode = dip->inode;
5673 struct btrfs_root *root = BTRFS_I(inode)->root;
5675 u32 *private = dip->csums;
5677 start = dip->logical_offset;
5679 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
5680 struct page *page = bvec->bv_page;
5683 unsigned long flags;
5685 local_irq_save(flags);
5686 kaddr = kmap_atomic(page, KM_IRQ0);
5687 csum = btrfs_csum_data(root, kaddr + bvec->bv_offset,
5688 csum, bvec->bv_len);
5689 btrfs_csum_final(csum, (char *)&csum);
5690 kunmap_atomic(kaddr, KM_IRQ0);
5691 local_irq_restore(flags);
5693 flush_dcache_page(bvec->bv_page);
5694 if (csum != *private) {
5695 printk(KERN_ERR "btrfs csum failed ino %llu off"
5696 " %llu csum %u private %u\n",
5697 (unsigned long long)btrfs_ino(inode),
5698 (unsigned long long)start,
5704 start += bvec->bv_len;
5707 } while (bvec <= bvec_end);
5709 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
5710 dip->logical_offset + dip->bytes - 1, GFP_NOFS);
5711 bio->bi_private = dip->private;
5716 /* If we had a csum failure make sure to clear the uptodate flag */
5718 clear_bit(BIO_UPTODATE, &bio->bi_flags);
5719 dio_end_io(bio, err);
5722 static void btrfs_endio_direct_write(struct bio *bio, int err)
5724 struct btrfs_dio_private *dip = bio->bi_private;
5725 struct inode *inode = dip->inode;
5726 struct btrfs_root *root = BTRFS_I(inode)->root;
5727 struct btrfs_trans_handle *trans;
5728 struct btrfs_ordered_extent *ordered = NULL;
5729 struct extent_state *cached_state = NULL;
5730 u64 ordered_offset = dip->logical_offset;
5731 u64 ordered_bytes = dip->bytes;
5737 ret = btrfs_dec_test_first_ordered_pending(inode, &ordered,
5745 trans = btrfs_join_transaction(root);
5746 if (IS_ERR(trans)) {
5750 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
5752 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags)) {
5753 ret = btrfs_ordered_update_i_size(inode, 0, ordered);
5755 err = btrfs_update_inode_fallback(trans, root, inode);
5759 lock_extent_bits(&BTRFS_I(inode)->io_tree, ordered->file_offset,
5760 ordered->file_offset + ordered->len - 1, 0,
5761 &cached_state, GFP_NOFS);
5763 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags)) {
5764 ret = btrfs_mark_extent_written(trans, inode,
5765 ordered->file_offset,
5766 ordered->file_offset +
5773 ret = insert_reserved_file_extent(trans, inode,
5774 ordered->file_offset,
5780 BTRFS_FILE_EXTENT_REG);
5781 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
5782 ordered->file_offset, ordered->len);
5790 add_pending_csums(trans, inode, ordered->file_offset, &ordered->list);
5791 ret = btrfs_ordered_update_i_size(inode, 0, ordered);
5792 if (!ret || !test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags))
5793 btrfs_update_inode_fallback(trans, root, inode);
5796 unlock_extent_cached(&BTRFS_I(inode)->io_tree, ordered->file_offset,
5797 ordered->file_offset + ordered->len - 1,
5798 &cached_state, GFP_NOFS);
5800 btrfs_delalloc_release_metadata(inode, ordered->len);
5801 btrfs_end_transaction(trans, root);
5802 ordered_offset = ordered->file_offset + ordered->len;
5803 btrfs_put_ordered_extent(ordered);
5804 btrfs_put_ordered_extent(ordered);
5808 * our bio might span multiple ordered extents. If we haven't
5809 * completed the accounting for the whole dio, go back and try again
5811 if (ordered_offset < dip->logical_offset + dip->bytes) {
5812 ordered_bytes = dip->logical_offset + dip->bytes -
5817 bio->bi_private = dip->private;
5822 /* If we had an error make sure to clear the uptodate flag */
5824 clear_bit(BIO_UPTODATE, &bio->bi_flags);
5825 dio_end_io(bio, err);
5828 static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw,
5829 struct bio *bio, int mirror_num,
5830 unsigned long bio_flags, u64 offset)
5833 struct btrfs_root *root = BTRFS_I(inode)->root;
5834 ret = btrfs_csum_one_bio(root, inode, bio, offset, 1);
5839 static void btrfs_end_dio_bio(struct bio *bio, int err)
5841 struct btrfs_dio_private *dip = bio->bi_private;
5844 printk(KERN_ERR "btrfs direct IO failed ino %llu rw %lu "
5845 "sector %#Lx len %u err no %d\n",
5846 (unsigned long long)btrfs_ino(dip->inode), bio->bi_rw,
5847 (unsigned long long)bio->bi_sector, bio->bi_size, err);
5851 * before atomic variable goto zero, we must make sure
5852 * dip->errors is perceived to be set.
5854 smp_mb__before_atomic_dec();
5857 /* if there are more bios still pending for this dio, just exit */
5858 if (!atomic_dec_and_test(&dip->pending_bios))
5862 bio_io_error(dip->orig_bio);
5864 set_bit(BIO_UPTODATE, &dip->orig_bio->bi_flags);
5865 bio_endio(dip->orig_bio, 0);
5871 static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev,
5872 u64 first_sector, gfp_t gfp_flags)
5874 int nr_vecs = bio_get_nr_vecs(bdev);
5875 return btrfs_bio_alloc(bdev, first_sector, nr_vecs, gfp_flags);
5878 static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode,
5879 int rw, u64 file_offset, int skip_sum,
5880 u32 *csums, int async_submit)
5882 int write = rw & REQ_WRITE;
5883 struct btrfs_root *root = BTRFS_I(inode)->root;
5887 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
5894 if (write && async_submit) {
5895 ret = btrfs_wq_submit_bio(root->fs_info,
5896 inode, rw, bio, 0, 0,
5898 __btrfs_submit_bio_start_direct_io,
5899 __btrfs_submit_bio_done);
5903 * If we aren't doing async submit, calculate the csum of the
5906 ret = btrfs_csum_one_bio(root, inode, bio, file_offset, 1);
5909 } else if (!skip_sum) {
5910 ret = btrfs_lookup_bio_sums_dio(root, inode, bio,
5911 file_offset, csums);
5917 ret = btrfs_map_bio(root, rw, bio, 0, async_submit);
5923 static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip,
5926 struct inode *inode = dip->inode;
5927 struct btrfs_root *root = BTRFS_I(inode)->root;
5928 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
5930 struct bio *orig_bio = dip->orig_bio;
5931 struct bio_vec *bvec = orig_bio->bi_io_vec;
5932 u64 start_sector = orig_bio->bi_sector;
5933 u64 file_offset = dip->logical_offset;
5937 u32 *csums = dip->csums;
5939 int async_submit = 0;
5940 int write = rw & REQ_WRITE;
5942 map_length = orig_bio->bi_size;
5943 ret = btrfs_map_block(map_tree, READ, start_sector << 9,
5944 &map_length, NULL, 0);
5950 if (map_length >= orig_bio->bi_size) {
5956 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS);
5959 bio->bi_private = dip;
5960 bio->bi_end_io = btrfs_end_dio_bio;
5961 atomic_inc(&dip->pending_bios);
5963 while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) {
5964 if (unlikely(map_length < submit_len + bvec->bv_len ||
5965 bio_add_page(bio, bvec->bv_page, bvec->bv_len,
5966 bvec->bv_offset) < bvec->bv_len)) {
5968 * inc the count before we submit the bio so
5969 * we know the end IO handler won't happen before
5970 * we inc the count. Otherwise, the dip might get freed
5971 * before we're done setting it up
5973 atomic_inc(&dip->pending_bios);
5974 ret = __btrfs_submit_dio_bio(bio, inode, rw,
5975 file_offset, skip_sum,
5976 csums, async_submit);
5979 atomic_dec(&dip->pending_bios);
5983 /* Write's use the ordered csums */
5984 if (!write && !skip_sum)
5985 csums = csums + nr_pages;
5986 start_sector += submit_len >> 9;
5987 file_offset += submit_len;
5992 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev,
5993 start_sector, GFP_NOFS);
5996 bio->bi_private = dip;
5997 bio->bi_end_io = btrfs_end_dio_bio;
5999 map_length = orig_bio->bi_size;
6000 ret = btrfs_map_block(map_tree, READ, start_sector << 9,
6001 &map_length, NULL, 0);
6007 submit_len += bvec->bv_len;
6014 ret = __btrfs_submit_dio_bio(bio, inode, rw, file_offset, skip_sum,
6015 csums, async_submit);
6023 * before atomic variable goto zero, we must
6024 * make sure dip->errors is perceived to be set.
6026 smp_mb__before_atomic_dec();
6027 if (atomic_dec_and_test(&dip->pending_bios))
6028 bio_io_error(dip->orig_bio);
6030 /* bio_end_io() will handle error, so we needn't return it */
6034 static void btrfs_submit_direct(int rw, struct bio *bio, struct inode *inode,
6037 struct btrfs_root *root = BTRFS_I(inode)->root;
6038 struct btrfs_dio_private *dip;
6039 struct bio_vec *bvec = bio->bi_io_vec;
6041 int write = rw & REQ_WRITE;
6044 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
6046 dip = kmalloc(sizeof(*dip), GFP_NOFS);
6053 /* Write's use the ordered csum stuff, so we don't need dip->csums */
6054 if (!write && !skip_sum) {
6055 dip->csums = kmalloc(sizeof(u32) * bio->bi_vcnt, GFP_NOFS);
6063 dip->private = bio->bi_private;
6065 dip->logical_offset = file_offset;
6069 dip->bytes += bvec->bv_len;
6071 } while (bvec <= (bio->bi_io_vec + bio->bi_vcnt - 1));
6073 dip->disk_bytenr = (u64)bio->bi_sector << 9;
6074 bio->bi_private = dip;
6076 dip->orig_bio = bio;
6077 atomic_set(&dip->pending_bios, 0);
6080 bio->bi_end_io = btrfs_endio_direct_write;
6082 bio->bi_end_io = btrfs_endio_direct_read;
6084 ret = btrfs_submit_direct_hook(rw, dip, skip_sum);
6089 * If this is a write, we need to clean up the reserved space and kill
6090 * the ordered extent.
6093 struct btrfs_ordered_extent *ordered;
6094 ordered = btrfs_lookup_ordered_extent(inode, file_offset);
6095 if (!test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags) &&
6096 !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags))
6097 btrfs_free_reserved_extent(root, ordered->start,
6099 btrfs_put_ordered_extent(ordered);
6100 btrfs_put_ordered_extent(ordered);
6102 bio_endio(bio, ret);
6105 static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb,
6106 const struct iovec *iov, loff_t offset,
6107 unsigned long nr_segs)
6113 unsigned blocksize_mask = root->sectorsize - 1;
6114 ssize_t retval = -EINVAL;
6115 loff_t end = offset;
6117 if (offset & blocksize_mask)
6120 /* Check the memory alignment. Blocks cannot straddle pages */
6121 for (seg = 0; seg < nr_segs; seg++) {
6122 addr = (unsigned long)iov[seg].iov_base;
6123 size = iov[seg].iov_len;
6125 if ((addr & blocksize_mask) || (size & blocksize_mask))
6128 /* If this is a write we don't need to check anymore */
6133 * Check to make sure we don't have duplicate iov_base's in this
6134 * iovec, if so return EINVAL, otherwise we'll get csum errors
6135 * when reading back.
6137 for (i = seg + 1; i < nr_segs; i++) {
6138 if (iov[seg].iov_base == iov[i].iov_base)
6146 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
6147 const struct iovec *iov, loff_t offset,
6148 unsigned long nr_segs)
6150 struct file *file = iocb->ki_filp;
6151 struct inode *inode = file->f_mapping->host;
6152 struct btrfs_ordered_extent *ordered;
6153 struct extent_state *cached_state = NULL;
6154 u64 lockstart, lockend;
6156 int writing = rw & WRITE;
6158 size_t count = iov_length(iov, nr_segs);
6160 if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov,
6166 lockend = offset + count - 1;
6169 ret = btrfs_delalloc_reserve_space(inode, count);
6175 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6176 0, &cached_state, GFP_NOFS);
6178 * We're concerned with the entire range that we're going to be
6179 * doing DIO to, so we need to make sure theres no ordered
6180 * extents in this range.
6182 ordered = btrfs_lookup_ordered_range(inode, lockstart,
6183 lockend - lockstart + 1);
6186 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6187 &cached_state, GFP_NOFS);
6188 btrfs_start_ordered_extent(inode, ordered, 1);
6189 btrfs_put_ordered_extent(ordered);
6194 * we don't use btrfs_set_extent_delalloc because we don't want
6195 * the dirty or uptodate bits
6198 write_bits = EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING;
6199 ret = set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6200 EXTENT_DELALLOC, 0, NULL, &cached_state,
6203 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6204 lockend, EXTENT_LOCKED | write_bits,
6205 1, 0, &cached_state, GFP_NOFS);
6210 free_extent_state(cached_state);
6211 cached_state = NULL;
6213 ret = __blockdev_direct_IO(rw, iocb, inode,
6214 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev,
6215 iov, offset, nr_segs, btrfs_get_blocks_direct, NULL,
6216 btrfs_submit_direct, 0);
6218 if (ret < 0 && ret != -EIOCBQUEUED) {
6219 clear_extent_bit(&BTRFS_I(inode)->io_tree, offset,
6220 offset + iov_length(iov, nr_segs) - 1,
6221 EXTENT_LOCKED | write_bits, 1, 0,
6222 &cached_state, GFP_NOFS);
6223 } else if (ret >= 0 && ret < iov_length(iov, nr_segs)) {
6225 * We're falling back to buffered, unlock the section we didn't
6228 clear_extent_bit(&BTRFS_I(inode)->io_tree, offset + ret,
6229 offset + iov_length(iov, nr_segs) - 1,
6230 EXTENT_LOCKED | write_bits, 1, 0,
6231 &cached_state, GFP_NOFS);
6234 free_extent_state(cached_state);
6238 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
6239 __u64 start, __u64 len)
6241 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap);
6244 int btrfs_readpage(struct file *file, struct page *page)
6246 struct extent_io_tree *tree;
6247 tree = &BTRFS_I(page->mapping->host)->io_tree;
6248 return extent_read_full_page(tree, page, btrfs_get_extent, 0);
6251 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
6253 struct extent_io_tree *tree;
6256 if (current->flags & PF_MEMALLOC) {
6257 redirty_page_for_writepage(wbc, page);
6261 tree = &BTRFS_I(page->mapping->host)->io_tree;
6262 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
6265 int btrfs_writepages(struct address_space *mapping,
6266 struct writeback_control *wbc)
6268 struct extent_io_tree *tree;
6270 tree = &BTRFS_I(mapping->host)->io_tree;
6271 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
6275 btrfs_readpages(struct file *file, struct address_space *mapping,
6276 struct list_head *pages, unsigned nr_pages)
6278 struct extent_io_tree *tree;
6279 tree = &BTRFS_I(mapping->host)->io_tree;
6280 return extent_readpages(tree, mapping, pages, nr_pages,
6283 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
6285 struct extent_io_tree *tree;
6286 struct extent_map_tree *map;
6289 tree = &BTRFS_I(page->mapping->host)->io_tree;
6290 map = &BTRFS_I(page->mapping->host)->extent_tree;
6291 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
6293 ClearPagePrivate(page);
6294 set_page_private(page, 0);
6295 page_cache_release(page);
6300 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
6302 if (PageWriteback(page) || PageDirty(page))
6304 return __btrfs_releasepage(page, gfp_flags & GFP_NOFS);
6307 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
6309 struct extent_io_tree *tree;
6310 struct btrfs_ordered_extent *ordered;
6311 struct extent_state *cached_state = NULL;
6312 u64 page_start = page_offset(page);
6313 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
6317 * we have the page locked, so new writeback can't start,
6318 * and the dirty bit won't be cleared while we are here.
6320 * Wait for IO on this page so that we can safely clear
6321 * the PagePrivate2 bit and do ordered accounting
6323 wait_on_page_writeback(page);
6325 tree = &BTRFS_I(page->mapping->host)->io_tree;
6327 btrfs_releasepage(page, GFP_NOFS);
6330 lock_extent_bits(tree, page_start, page_end, 0, &cached_state,
6332 ordered = btrfs_lookup_ordered_extent(page->mapping->host,
6336 * IO on this page will never be started, so we need
6337 * to account for any ordered extents now
6339 clear_extent_bit(tree, page_start, page_end,
6340 EXTENT_DIRTY | EXTENT_DELALLOC |
6341 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING, 1, 0,
6342 &cached_state, GFP_NOFS);
6344 * whoever cleared the private bit is responsible
6345 * for the finish_ordered_io
6347 if (TestClearPagePrivate2(page)) {
6348 btrfs_finish_ordered_io(page->mapping->host,
6349 page_start, page_end);
6351 btrfs_put_ordered_extent(ordered);
6352 cached_state = NULL;
6353 lock_extent_bits(tree, page_start, page_end, 0, &cached_state,
6356 clear_extent_bit(tree, page_start, page_end,
6357 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
6358 EXTENT_DO_ACCOUNTING, 1, 1, &cached_state, GFP_NOFS);
6359 __btrfs_releasepage(page, GFP_NOFS);
6361 ClearPageChecked(page);
6362 if (PagePrivate(page)) {
6363 ClearPagePrivate(page);
6364 set_page_private(page, 0);
6365 page_cache_release(page);
6370 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
6371 * called from a page fault handler when a page is first dirtied. Hence we must
6372 * be careful to check for EOF conditions here. We set the page up correctly
6373 * for a written page which means we get ENOSPC checking when writing into
6374 * holes and correct delalloc and unwritten extent mapping on filesystems that
6375 * support these features.
6377 * We are not allowed to take the i_mutex here so we have to play games to
6378 * protect against truncate races as the page could now be beyond EOF. Because
6379 * vmtruncate() writes the inode size before removing pages, once we have the
6380 * page lock we can determine safely if the page is beyond EOF. If it is not
6381 * beyond EOF, then the page is guaranteed safe against truncation until we
6384 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
6386 struct page *page = vmf->page;
6387 struct inode *inode = fdentry(vma->vm_file)->d_inode;
6388 struct btrfs_root *root = BTRFS_I(inode)->root;
6389 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6390 struct btrfs_ordered_extent *ordered;
6391 struct extent_state *cached_state = NULL;
6393 unsigned long zero_start;
6399 /* Need this to keep space reservations serialized */
6400 mutex_lock(&inode->i_mutex);
6401 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
6402 mutex_unlock(&inode->i_mutex);
6404 ret = btrfs_update_time(vma->vm_file);
6408 else /* -ENOSPC, -EIO, etc */
6409 ret = VM_FAULT_SIGBUS;
6413 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
6416 size = i_size_read(inode);
6417 page_start = page_offset(page);
6418 page_end = page_start + PAGE_CACHE_SIZE - 1;
6420 if ((page->mapping != inode->i_mapping) ||
6421 (page_start >= size)) {
6422 /* page got truncated out from underneath us */
6425 wait_on_page_writeback(page);
6427 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state,
6429 set_page_extent_mapped(page);
6432 * we can't set the delalloc bits if there are pending ordered
6433 * extents. Drop our locks and wait for them to finish
6435 ordered = btrfs_lookup_ordered_extent(inode, page_start);
6437 unlock_extent_cached(io_tree, page_start, page_end,
6438 &cached_state, GFP_NOFS);
6440 btrfs_start_ordered_extent(inode, ordered, 1);
6441 btrfs_put_ordered_extent(ordered);
6446 * XXX - page_mkwrite gets called every time the page is dirtied, even
6447 * if it was already dirty, so for space accounting reasons we need to
6448 * clear any delalloc bits for the range we are fixing to save. There
6449 * is probably a better way to do this, but for now keep consistent with
6450 * prepare_pages in the normal write path.
6452 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
6453 EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
6454 0, 0, &cached_state, GFP_NOFS);
6456 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
6459 unlock_extent_cached(io_tree, page_start, page_end,
6460 &cached_state, GFP_NOFS);
6461 ret = VM_FAULT_SIGBUS;
6466 /* page is wholly or partially inside EOF */
6467 if (page_start + PAGE_CACHE_SIZE > size)
6468 zero_start = size & ~PAGE_CACHE_MASK;
6470 zero_start = PAGE_CACHE_SIZE;
6472 if (zero_start != PAGE_CACHE_SIZE) {
6474 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
6475 flush_dcache_page(page);
6478 ClearPageChecked(page);
6479 set_page_dirty(page);
6480 SetPageUptodate(page);
6482 BTRFS_I(inode)->last_trans = root->fs_info->generation;
6483 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
6485 unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS);
6489 return VM_FAULT_LOCKED;
6491 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
6496 static int btrfs_truncate(struct inode *inode)
6498 struct btrfs_root *root = BTRFS_I(inode)->root;
6499 struct btrfs_block_rsv *rsv;
6502 struct btrfs_trans_handle *trans;
6504 u64 mask = root->sectorsize - 1;
6505 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
6507 ret = btrfs_truncate_page(inode->i_mapping, inode->i_size);
6511 btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
6512 btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
6515 * Yes ladies and gentelment, this is indeed ugly. The fact is we have
6516 * 3 things going on here
6518 * 1) We need to reserve space for our orphan item and the space to
6519 * delete our orphan item. Lord knows we don't want to have a dangling
6520 * orphan item because we didn't reserve space to remove it.
6522 * 2) We need to reserve space to update our inode.
6524 * 3) We need to have something to cache all the space that is going to
6525 * be free'd up by the truncate operation, but also have some slack
6526 * space reserved in case it uses space during the truncate (thank you
6527 * very much snapshotting).
6529 * And we need these to all be seperate. The fact is we can use alot of
6530 * space doing the truncate, and we have no earthly idea how much space
6531 * we will use, so we need the truncate reservation to be seperate so it
6532 * doesn't end up using space reserved for updating the inode or
6533 * removing the orphan item. We also need to be able to stop the
6534 * transaction and start a new one, which means we need to be able to
6535 * update the inode several times, and we have no idea of knowing how
6536 * many times that will be, so we can't just reserve 1 item for the
6537 * entirety of the opration, so that has to be done seperately as well.
6538 * Then there is the orphan item, which does indeed need to be held on
6539 * to for the whole operation, and we need nobody to touch this reserved
6540 * space except the orphan code.
6542 * So that leaves us with
6544 * 1) root->orphan_block_rsv - for the orphan deletion.
6545 * 2) rsv - for the truncate reservation, which we will steal from the
6546 * transaction reservation.
6547 * 3) fs_info->trans_block_rsv - this will have 1 items worth left for
6548 * updating the inode.
6550 rsv = btrfs_alloc_block_rsv(root);
6553 rsv->size = min_size;
6556 * 1 for the truncate slack space
6557 * 1 for the orphan item we're going to add
6558 * 1 for the orphan item deletion
6559 * 1 for updating the inode.
6561 trans = btrfs_start_transaction(root, 4);
6562 if (IS_ERR(trans)) {
6563 err = PTR_ERR(trans);
6567 /* Migrate the slack space for the truncate to our reserve */
6568 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv,
6572 ret = btrfs_orphan_add(trans, inode);
6574 btrfs_end_transaction(trans, root);
6579 * setattr is responsible for setting the ordered_data_close flag,
6580 * but that is only tested during the last file release. That
6581 * could happen well after the next commit, leaving a great big
6582 * window where new writes may get lost if someone chooses to write
6583 * to this file after truncating to zero
6585 * The inode doesn't have any dirty data here, and so if we commit
6586 * this is a noop. If someone immediately starts writing to the inode
6587 * it is very likely we'll catch some of their writes in this
6588 * transaction, and the commit will find this file on the ordered
6589 * data list with good things to send down.
6591 * This is a best effort solution, there is still a window where
6592 * using truncate to replace the contents of the file will
6593 * end up with a zero length file after a crash.
6595 if (inode->i_size == 0 && BTRFS_I(inode)->ordered_data_close)
6596 btrfs_add_ordered_operation(trans, root, inode);
6599 ret = btrfs_block_rsv_refill(root, rsv, min_size);
6602 * This can only happen with the original transaction we
6603 * started above, every other time we shouldn't have a
6604 * transaction started yet.
6613 /* Just need the 1 for updating the inode */
6614 trans = btrfs_start_transaction(root, 1);
6615 if (IS_ERR(trans)) {
6616 ret = err = PTR_ERR(trans);
6622 trans->block_rsv = rsv;
6624 ret = btrfs_truncate_inode_items(trans, root, inode,
6626 BTRFS_EXTENT_DATA_KEY);
6627 if (ret != -EAGAIN) {
6632 trans->block_rsv = &root->fs_info->trans_block_rsv;
6633 ret = btrfs_update_inode(trans, root, inode);
6639 nr = trans->blocks_used;
6640 btrfs_end_transaction(trans, root);
6642 btrfs_btree_balance_dirty(root, nr);
6645 if (ret == 0 && inode->i_nlink > 0) {
6646 trans->block_rsv = root->orphan_block_rsv;
6647 ret = btrfs_orphan_del(trans, inode);
6650 } else if (ret && inode->i_nlink > 0) {
6652 * Failed to do the truncate, remove us from the in memory
6655 ret = btrfs_orphan_del(NULL, inode);
6659 trans->block_rsv = &root->fs_info->trans_block_rsv;
6660 ret = btrfs_update_inode(trans, root, inode);
6664 nr = trans->blocks_used;
6665 ret = btrfs_end_transaction(trans, root);
6666 btrfs_btree_balance_dirty(root, nr);
6670 btrfs_free_block_rsv(root, rsv);
6679 * create a new subvolume directory/inode (helper for the ioctl).
6681 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
6682 struct btrfs_root *new_root, u64 new_dirid)
6684 struct inode *inode;
6688 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid,
6689 new_dirid, S_IFDIR | 0700, &index);
6691 return PTR_ERR(inode);
6692 inode->i_op = &btrfs_dir_inode_operations;
6693 inode->i_fop = &btrfs_dir_file_operations;
6695 set_nlink(inode, 1);
6696 btrfs_i_size_write(inode, 0);
6698 err = btrfs_update_inode(trans, new_root, inode);
6705 struct inode *btrfs_alloc_inode(struct super_block *sb)
6707 struct btrfs_inode *ei;
6708 struct inode *inode;
6710 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
6715 ei->space_info = NULL;
6719 ei->last_sub_trans = 0;
6720 ei->logged_trans = 0;
6721 ei->delalloc_bytes = 0;
6722 ei->disk_i_size = 0;
6725 ei->index_cnt = (u64)-1;
6726 ei->last_unlink_trans = 0;
6728 spin_lock_init(&ei->lock);
6729 ei->outstanding_extents = 0;
6730 ei->reserved_extents = 0;
6732 ei->ordered_data_close = 0;
6733 ei->orphan_meta_reserved = 0;
6734 ei->dummy_inode = 0;
6736 ei->delalloc_meta_reserved = 0;
6737 ei->force_compress = BTRFS_COMPRESS_NONE;
6739 ei->delayed_node = NULL;
6741 inode = &ei->vfs_inode;
6742 extent_map_tree_init(&ei->extent_tree);
6743 extent_io_tree_init(&ei->io_tree, &inode->i_data);
6744 extent_io_tree_init(&ei->io_failure_tree, &inode->i_data);
6745 mutex_init(&ei->log_mutex);
6746 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
6747 INIT_LIST_HEAD(&ei->i_orphan);
6748 INIT_LIST_HEAD(&ei->delalloc_inodes);
6749 INIT_LIST_HEAD(&ei->ordered_operations);
6750 RB_CLEAR_NODE(&ei->rb_node);
6755 static void btrfs_i_callback(struct rcu_head *head)
6757 struct inode *inode = container_of(head, struct inode, i_rcu);
6758 INIT_LIST_HEAD(&inode->i_dentry);
6759 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
6762 void btrfs_destroy_inode(struct inode *inode)
6764 struct btrfs_ordered_extent *ordered;
6765 struct btrfs_root *root = BTRFS_I(inode)->root;
6767 WARN_ON(!list_empty(&inode->i_dentry));
6768 WARN_ON(inode->i_data.nrpages);
6769 WARN_ON(BTRFS_I(inode)->outstanding_extents);
6770 WARN_ON(BTRFS_I(inode)->reserved_extents);
6771 WARN_ON(BTRFS_I(inode)->delalloc_bytes);
6772 WARN_ON(BTRFS_I(inode)->csum_bytes);
6775 * This can happen where we create an inode, but somebody else also
6776 * created the same inode and we need to destroy the one we already
6783 * Make sure we're properly removed from the ordered operation
6787 if (!list_empty(&BTRFS_I(inode)->ordered_operations)) {
6788 spin_lock(&root->fs_info->ordered_extent_lock);
6789 list_del_init(&BTRFS_I(inode)->ordered_operations);
6790 spin_unlock(&root->fs_info->ordered_extent_lock);
6793 spin_lock(&root->orphan_lock);
6794 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
6795 printk(KERN_INFO "BTRFS: inode %llu still on the orphan list\n",
6796 (unsigned long long)btrfs_ino(inode));
6797 list_del_init(&BTRFS_I(inode)->i_orphan);
6799 spin_unlock(&root->orphan_lock);
6802 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
6806 printk(KERN_ERR "btrfs found ordered "
6807 "extent %llu %llu on inode cleanup\n",
6808 (unsigned long long)ordered->file_offset,
6809 (unsigned long long)ordered->len);
6810 btrfs_remove_ordered_extent(inode, ordered);
6811 btrfs_put_ordered_extent(ordered);
6812 btrfs_put_ordered_extent(ordered);
6815 inode_tree_del(inode);
6816 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
6818 btrfs_remove_delayed_node(inode);
6819 call_rcu(&inode->i_rcu, btrfs_i_callback);
6822 int btrfs_drop_inode(struct inode *inode)
6824 struct btrfs_root *root = BTRFS_I(inode)->root;
6826 if (btrfs_root_refs(&root->root_item) == 0 &&
6827 !btrfs_is_free_space_inode(root, inode))
6830 return generic_drop_inode(inode);
6833 static void init_once(void *foo)
6835 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
6837 inode_init_once(&ei->vfs_inode);
6840 void btrfs_destroy_cachep(void)
6842 if (btrfs_inode_cachep)
6843 kmem_cache_destroy(btrfs_inode_cachep);
6844 if (btrfs_trans_handle_cachep)
6845 kmem_cache_destroy(btrfs_trans_handle_cachep);
6846 if (btrfs_transaction_cachep)
6847 kmem_cache_destroy(btrfs_transaction_cachep);
6848 if (btrfs_path_cachep)
6849 kmem_cache_destroy(btrfs_path_cachep);
6850 if (btrfs_free_space_cachep)
6851 kmem_cache_destroy(btrfs_free_space_cachep);
6854 int btrfs_init_cachep(void)
6856 btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache",
6857 sizeof(struct btrfs_inode), 0,
6858 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once);
6859 if (!btrfs_inode_cachep)
6862 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache",
6863 sizeof(struct btrfs_trans_handle), 0,
6864 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6865 if (!btrfs_trans_handle_cachep)
6868 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache",
6869 sizeof(struct btrfs_transaction), 0,
6870 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6871 if (!btrfs_transaction_cachep)
6874 btrfs_path_cachep = kmem_cache_create("btrfs_path_cache",
6875 sizeof(struct btrfs_path), 0,
6876 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6877 if (!btrfs_path_cachep)
6880 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space_cache",
6881 sizeof(struct btrfs_free_space), 0,
6882 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6883 if (!btrfs_free_space_cachep)
6888 btrfs_destroy_cachep();
6892 static int btrfs_getattr(struct vfsmount *mnt,
6893 struct dentry *dentry, struct kstat *stat)
6895 struct inode *inode = dentry->d_inode;
6896 u32 blocksize = inode->i_sb->s_blocksize;
6898 generic_fillattr(inode, stat);
6899 stat->dev = BTRFS_I(inode)->root->anon_dev;
6900 stat->blksize = PAGE_CACHE_SIZE;
6901 stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) +
6902 ALIGN(BTRFS_I(inode)->delalloc_bytes, blocksize)) >> 9;
6907 * If a file is moved, it will inherit the cow and compression flags of the new
6910 static void fixup_inode_flags(struct inode *dir, struct inode *inode)
6912 struct btrfs_inode *b_dir = BTRFS_I(dir);
6913 struct btrfs_inode *b_inode = BTRFS_I(inode);
6915 if (b_dir->flags & BTRFS_INODE_NODATACOW)
6916 b_inode->flags |= BTRFS_INODE_NODATACOW;
6918 b_inode->flags &= ~BTRFS_INODE_NODATACOW;
6920 if (b_dir->flags & BTRFS_INODE_COMPRESS)
6921 b_inode->flags |= BTRFS_INODE_COMPRESS;
6923 b_inode->flags &= ~BTRFS_INODE_COMPRESS;
6926 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
6927 struct inode *new_dir, struct dentry *new_dentry)
6929 struct btrfs_trans_handle *trans;
6930 struct btrfs_root *root = BTRFS_I(old_dir)->root;
6931 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
6932 struct inode *new_inode = new_dentry->d_inode;
6933 struct inode *old_inode = old_dentry->d_inode;
6934 struct timespec ctime = CURRENT_TIME;
6938 u64 old_ino = btrfs_ino(old_inode);
6940 if (btrfs_ino(new_dir) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
6943 /* we only allow rename subvolume link between subvolumes */
6944 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
6947 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
6948 (new_inode && btrfs_ino(new_inode) == BTRFS_FIRST_FREE_OBJECTID))
6951 if (S_ISDIR(old_inode->i_mode) && new_inode &&
6952 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
6955 * we're using rename to replace one file with another.
6956 * and the replacement file is large. Start IO on it now so
6957 * we don't add too much work to the end of the transaction
6959 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size &&
6960 old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
6961 filemap_flush(old_inode->i_mapping);
6963 /* close the racy window with snapshot create/destroy ioctl */
6964 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
6965 down_read(&root->fs_info->subvol_sem);
6967 * We want to reserve the absolute worst case amount of items. So if
6968 * both inodes are subvols and we need to unlink them then that would
6969 * require 4 item modifications, but if they are both normal inodes it
6970 * would require 5 item modifications, so we'll assume their normal
6971 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
6972 * should cover the worst case number of items we'll modify.
6974 trans = btrfs_start_transaction(root, 20);
6975 if (IS_ERR(trans)) {
6976 ret = PTR_ERR(trans);
6981 btrfs_record_root_in_trans(trans, dest);
6983 ret = btrfs_set_inode_index(new_dir, &index);
6987 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
6988 /* force full log commit if subvolume involved. */
6989 root->fs_info->last_trans_log_full_commit = trans->transid;
6991 ret = btrfs_insert_inode_ref(trans, dest,
6992 new_dentry->d_name.name,
6993 new_dentry->d_name.len,
6995 btrfs_ino(new_dir), index);
6999 * this is an ugly little race, but the rename is required
7000 * to make sure that if we crash, the inode is either at the
7001 * old name or the new one. pinning the log transaction lets
7002 * us make sure we don't allow a log commit to come in after
7003 * we unlink the name but before we add the new name back in.
7005 btrfs_pin_log_trans(root);
7008 * make sure the inode gets flushed if it is replacing
7011 if (new_inode && new_inode->i_size && S_ISREG(old_inode->i_mode))
7012 btrfs_add_ordered_operation(trans, root, old_inode);
7014 old_dir->i_ctime = old_dir->i_mtime = ctime;
7015 new_dir->i_ctime = new_dir->i_mtime = ctime;
7016 old_inode->i_ctime = ctime;
7018 if (old_dentry->d_parent != new_dentry->d_parent)
7019 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1);
7021 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
7022 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
7023 ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid,
7024 old_dentry->d_name.name,
7025 old_dentry->d_name.len);
7027 ret = __btrfs_unlink_inode(trans, root, old_dir,
7028 old_dentry->d_inode,
7029 old_dentry->d_name.name,
7030 old_dentry->d_name.len);
7032 ret = btrfs_update_inode(trans, root, old_inode);
7037 new_inode->i_ctime = CURRENT_TIME;
7038 if (unlikely(btrfs_ino(new_inode) ==
7039 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
7040 root_objectid = BTRFS_I(new_inode)->location.objectid;
7041 ret = btrfs_unlink_subvol(trans, dest, new_dir,
7043 new_dentry->d_name.name,
7044 new_dentry->d_name.len);
7045 BUG_ON(new_inode->i_nlink == 0);
7047 ret = btrfs_unlink_inode(trans, dest, new_dir,
7048 new_dentry->d_inode,
7049 new_dentry->d_name.name,
7050 new_dentry->d_name.len);
7053 if (new_inode->i_nlink == 0) {
7054 ret = btrfs_orphan_add(trans, new_dentry->d_inode);
7059 fixup_inode_flags(new_dir, old_inode);
7061 ret = btrfs_add_link(trans, new_dir, old_inode,
7062 new_dentry->d_name.name,
7063 new_dentry->d_name.len, 0, index);
7066 if (old_ino != BTRFS_FIRST_FREE_OBJECTID) {
7067 struct dentry *parent = new_dentry->d_parent;
7068 btrfs_log_new_name(trans, old_inode, old_dir, parent);
7069 btrfs_end_log_trans(root);
7072 btrfs_end_transaction(trans, root);
7074 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
7075 up_read(&root->fs_info->subvol_sem);
7081 * some fairly slow code that needs optimization. This walks the list
7082 * of all the inodes with pending delalloc and forces them to disk.
7084 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
7086 struct list_head *head = &root->fs_info->delalloc_inodes;
7087 struct btrfs_inode *binode;
7088 struct inode *inode;
7090 if (root->fs_info->sb->s_flags & MS_RDONLY)
7093 spin_lock(&root->fs_info->delalloc_lock);
7094 while (!list_empty(head)) {
7095 binode = list_entry(head->next, struct btrfs_inode,
7097 inode = igrab(&binode->vfs_inode);
7099 list_del_init(&binode->delalloc_inodes);
7100 spin_unlock(&root->fs_info->delalloc_lock);
7102 filemap_flush(inode->i_mapping);
7104 btrfs_add_delayed_iput(inode);
7109 spin_lock(&root->fs_info->delalloc_lock);
7111 spin_unlock(&root->fs_info->delalloc_lock);
7113 /* the filemap_flush will queue IO into the worker threads, but
7114 * we have to make sure the IO is actually started and that
7115 * ordered extents get created before we return
7117 atomic_inc(&root->fs_info->async_submit_draining);
7118 while (atomic_read(&root->fs_info->nr_async_submits) ||
7119 atomic_read(&root->fs_info->async_delalloc_pages)) {
7120 wait_event(root->fs_info->async_submit_wait,
7121 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
7122 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
7124 atomic_dec(&root->fs_info->async_submit_draining);
7128 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
7129 const char *symname)
7131 struct btrfs_trans_handle *trans;
7132 struct btrfs_root *root = BTRFS_I(dir)->root;
7133 struct btrfs_path *path;
7134 struct btrfs_key key;
7135 struct inode *inode = NULL;
7143 struct btrfs_file_extent_item *ei;
7144 struct extent_buffer *leaf;
7145 unsigned long nr = 0;
7147 name_len = strlen(symname) + 1;
7148 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
7149 return -ENAMETOOLONG;
7152 * 2 items for inode item and ref
7153 * 2 items for dir items
7154 * 1 item for xattr if selinux is on
7156 trans = btrfs_start_transaction(root, 5);
7158 return PTR_ERR(trans);
7160 err = btrfs_find_free_ino(root, &objectid);
7164 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
7165 dentry->d_name.len, btrfs_ino(dir), objectid,
7166 S_IFLNK|S_IRWXUGO, &index);
7167 if (IS_ERR(inode)) {
7168 err = PTR_ERR(inode);
7172 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
7179 * If the active LSM wants to access the inode during
7180 * d_instantiate it needs these. Smack checks to see
7181 * if the filesystem supports xattrs by looking at the
7184 inode->i_fop = &btrfs_file_operations;
7185 inode->i_op = &btrfs_file_inode_operations;
7187 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
7191 inode->i_mapping->a_ops = &btrfs_aops;
7192 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
7193 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
7198 path = btrfs_alloc_path();
7204 key.objectid = btrfs_ino(inode);
7206 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
7207 datasize = btrfs_file_extent_calc_inline_size(name_len);
7208 err = btrfs_insert_empty_item(trans, root, path, &key,
7212 btrfs_free_path(path);
7215 leaf = path->nodes[0];
7216 ei = btrfs_item_ptr(leaf, path->slots[0],
7217 struct btrfs_file_extent_item);
7218 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
7219 btrfs_set_file_extent_type(leaf, ei,
7220 BTRFS_FILE_EXTENT_INLINE);
7221 btrfs_set_file_extent_encryption(leaf, ei, 0);
7222 btrfs_set_file_extent_compression(leaf, ei, 0);
7223 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
7224 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
7226 ptr = btrfs_file_extent_inline_start(ei);
7227 write_extent_buffer(leaf, symname, ptr, name_len);
7228 btrfs_mark_buffer_dirty(leaf);
7229 btrfs_free_path(path);
7231 inode->i_op = &btrfs_symlink_inode_operations;
7232 inode->i_mapping->a_ops = &btrfs_symlink_aops;
7233 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
7234 inode_set_bytes(inode, name_len);
7235 btrfs_i_size_write(inode, name_len - 1);
7236 err = btrfs_update_inode(trans, root, inode);
7242 d_instantiate(dentry, inode);
7243 nr = trans->blocks_used;
7244 btrfs_end_transaction(trans, root);
7246 inode_dec_link_count(inode);
7249 btrfs_btree_balance_dirty(root, nr);
7253 static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
7254 u64 start, u64 num_bytes, u64 min_size,
7255 loff_t actual_len, u64 *alloc_hint,
7256 struct btrfs_trans_handle *trans)
7258 struct btrfs_root *root = BTRFS_I(inode)->root;
7259 struct btrfs_key ins;
7260 u64 cur_offset = start;
7263 bool own_trans = true;
7267 while (num_bytes > 0) {
7269 trans = btrfs_start_transaction(root, 3);
7270 if (IS_ERR(trans)) {
7271 ret = PTR_ERR(trans);
7276 ret = btrfs_reserve_extent(trans, root, num_bytes, min_size,
7277 0, *alloc_hint, (u64)-1, &ins, 1);
7280 btrfs_end_transaction(trans, root);
7284 ret = insert_reserved_file_extent(trans, inode,
7285 cur_offset, ins.objectid,
7286 ins.offset, ins.offset,
7287 ins.offset, 0, 0, 0,
7288 BTRFS_FILE_EXTENT_PREALLOC);
7290 btrfs_drop_extent_cache(inode, cur_offset,
7291 cur_offset + ins.offset -1, 0);
7293 num_bytes -= ins.offset;
7294 cur_offset += ins.offset;
7295 *alloc_hint = ins.objectid + ins.offset;
7297 inode->i_ctime = CURRENT_TIME;
7298 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
7299 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
7300 (actual_len > inode->i_size) &&
7301 (cur_offset > inode->i_size)) {
7302 if (cur_offset > actual_len)
7303 i_size = actual_len;
7305 i_size = cur_offset;
7306 i_size_write(inode, i_size);
7307 btrfs_ordered_update_i_size(inode, i_size, NULL);
7310 ret = btrfs_update_inode(trans, root, inode);
7314 btrfs_end_transaction(trans, root);
7319 int btrfs_prealloc_file_range(struct inode *inode, int mode,
7320 u64 start, u64 num_bytes, u64 min_size,
7321 loff_t actual_len, u64 *alloc_hint)
7323 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
7324 min_size, actual_len, alloc_hint,
7328 int btrfs_prealloc_file_range_trans(struct inode *inode,
7329 struct btrfs_trans_handle *trans, int mode,
7330 u64 start, u64 num_bytes, u64 min_size,
7331 loff_t actual_len, u64 *alloc_hint)
7333 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
7334 min_size, actual_len, alloc_hint, trans);
7337 static int btrfs_set_page_dirty(struct page *page)
7339 return __set_page_dirty_nobuffers(page);
7342 static int btrfs_permission(struct inode *inode, int mask)
7344 struct btrfs_root *root = BTRFS_I(inode)->root;
7345 umode_t mode = inode->i_mode;
7347 if (mask & MAY_WRITE &&
7348 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) {
7349 if (btrfs_root_readonly(root))
7351 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
7354 return generic_permission(inode, mask);
7357 static const struct inode_operations btrfs_dir_inode_operations = {
7358 .getattr = btrfs_getattr,
7359 .lookup = btrfs_lookup,
7360 .create = btrfs_create,
7361 .unlink = btrfs_unlink,
7363 .mkdir = btrfs_mkdir,
7364 .rmdir = btrfs_rmdir,
7365 .rename = btrfs_rename,
7366 .symlink = btrfs_symlink,
7367 .setattr = btrfs_setattr,
7368 .mknod = btrfs_mknod,
7369 .setxattr = btrfs_setxattr,
7370 .getxattr = btrfs_getxattr,
7371 .listxattr = btrfs_listxattr,
7372 .removexattr = btrfs_removexattr,
7373 .permission = btrfs_permission,
7374 .get_acl = btrfs_get_acl,
7376 static const struct inode_operations btrfs_dir_ro_inode_operations = {
7377 .lookup = btrfs_lookup,
7378 .permission = btrfs_permission,
7379 .get_acl = btrfs_get_acl,
7382 static const struct file_operations btrfs_dir_file_operations = {
7383 .llseek = generic_file_llseek,
7384 .read = generic_read_dir,
7385 .readdir = btrfs_real_readdir,
7386 .unlocked_ioctl = btrfs_ioctl,
7387 #ifdef CONFIG_COMPAT
7388 .compat_ioctl = btrfs_ioctl,
7390 .release = btrfs_release_file,
7391 .fsync = btrfs_sync_file,
7394 static struct extent_io_ops btrfs_extent_io_ops = {
7395 .fill_delalloc = run_delalloc_range,
7396 .submit_bio_hook = btrfs_submit_bio_hook,
7397 .merge_bio_hook = btrfs_merge_bio_hook,
7398 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
7399 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
7400 .writepage_start_hook = btrfs_writepage_start_hook,
7401 .set_bit_hook = btrfs_set_bit_hook,
7402 .clear_bit_hook = btrfs_clear_bit_hook,
7403 .merge_extent_hook = btrfs_merge_extent_hook,
7404 .split_extent_hook = btrfs_split_extent_hook,
7408 * btrfs doesn't support the bmap operation because swapfiles
7409 * use bmap to make a mapping of extents in the file. They assume
7410 * these extents won't change over the life of the file and they
7411 * use the bmap result to do IO directly to the drive.
7413 * the btrfs bmap call would return logical addresses that aren't
7414 * suitable for IO and they also will change frequently as COW
7415 * operations happen. So, swapfile + btrfs == corruption.
7417 * For now we're avoiding this by dropping bmap.
7419 static const struct address_space_operations btrfs_aops = {
7420 .readpage = btrfs_readpage,
7421 .writepage = btrfs_writepage,
7422 .writepages = btrfs_writepages,
7423 .readpages = btrfs_readpages,
7424 .direct_IO = btrfs_direct_IO,
7425 .invalidatepage = btrfs_invalidatepage,
7426 .releasepage = btrfs_releasepage,
7427 .set_page_dirty = btrfs_set_page_dirty,
7428 .error_remove_page = generic_error_remove_page,
7431 static const struct address_space_operations btrfs_symlink_aops = {
7432 .readpage = btrfs_readpage,
7433 .writepage = btrfs_writepage,
7434 .invalidatepage = btrfs_invalidatepage,
7435 .releasepage = btrfs_releasepage,
7438 static const struct inode_operations btrfs_file_inode_operations = {
7439 .getattr = btrfs_getattr,
7440 .setattr = btrfs_setattr,
7441 .setxattr = btrfs_setxattr,
7442 .getxattr = btrfs_getxattr,
7443 .listxattr = btrfs_listxattr,
7444 .removexattr = btrfs_removexattr,
7445 .permission = btrfs_permission,
7446 .fiemap = btrfs_fiemap,
7447 .get_acl = btrfs_get_acl,
7449 static const struct inode_operations btrfs_special_inode_operations = {
7450 .getattr = btrfs_getattr,
7451 .setattr = btrfs_setattr,
7452 .permission = btrfs_permission,
7453 .setxattr = btrfs_setxattr,
7454 .getxattr = btrfs_getxattr,
7455 .listxattr = btrfs_listxattr,
7456 .removexattr = btrfs_removexattr,
7457 .get_acl = btrfs_get_acl,
7459 static const struct inode_operations btrfs_symlink_inode_operations = {
7460 .readlink = generic_readlink,
7461 .follow_link = page_follow_link_light,
7462 .put_link = page_put_link,
7463 .getattr = btrfs_getattr,
7464 .setattr = btrfs_setattr,
7465 .permission = btrfs_permission,
7466 .setxattr = btrfs_setxattr,
7467 .getxattr = btrfs_getxattr,
7468 .listxattr = btrfs_listxattr,
7469 .removexattr = btrfs_removexattr,
7470 .get_acl = btrfs_get_acl,
7473 const struct dentry_operations btrfs_dentry_operations = {
7474 .d_delete = btrfs_dentry_delete,
7475 .d_release = btrfs_dentry_release,