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>
44 #include "transaction.h"
45 #include "btrfs_inode.h"
47 #include "print-tree.h"
49 #include "ordered-data.h"
52 #include "compression.h"
54 #include "free-space-cache.h"
55 #include "inode-map.h"
57 struct btrfs_iget_args {
59 struct btrfs_root *root;
62 static const struct inode_operations btrfs_dir_inode_operations;
63 static const struct inode_operations btrfs_symlink_inode_operations;
64 static const struct inode_operations btrfs_dir_ro_inode_operations;
65 static const struct inode_operations btrfs_special_inode_operations;
66 static const struct inode_operations btrfs_file_inode_operations;
67 static const struct address_space_operations btrfs_aops;
68 static const struct address_space_operations btrfs_symlink_aops;
69 static const struct file_operations btrfs_dir_file_operations;
70 static struct extent_io_ops btrfs_extent_io_ops;
72 static struct kmem_cache *btrfs_inode_cachep;
73 struct kmem_cache *btrfs_trans_handle_cachep;
74 struct kmem_cache *btrfs_transaction_cachep;
75 struct kmem_cache *btrfs_path_cachep;
76 struct kmem_cache *btrfs_free_space_cachep;
79 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
80 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
81 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
82 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
83 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
84 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
85 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
86 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
89 static int btrfs_setsize(struct inode *inode, loff_t newsize);
90 static int btrfs_truncate(struct inode *inode);
91 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end);
92 static noinline int cow_file_range(struct inode *inode,
93 struct page *locked_page,
94 u64 start, u64 end, int *page_started,
95 unsigned long *nr_written, int unlock);
97 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
98 struct inode *inode, struct inode *dir,
99 const struct qstr *qstr)
103 err = btrfs_init_acl(trans, inode, dir);
105 err = btrfs_xattr_security_init(trans, inode, dir, qstr);
110 * this does all the hard work for inserting an inline extent into
111 * the btree. The caller should have done a btrfs_drop_extents so that
112 * no overlapping inline items exist in the btree
114 static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
115 struct btrfs_root *root, struct inode *inode,
116 u64 start, size_t size, size_t compressed_size,
118 struct page **compressed_pages)
120 struct btrfs_key key;
121 struct btrfs_path *path;
122 struct extent_buffer *leaf;
123 struct page *page = NULL;
126 struct btrfs_file_extent_item *ei;
129 size_t cur_size = size;
131 unsigned long offset;
133 if (compressed_size && compressed_pages)
134 cur_size = compressed_size;
136 path = btrfs_alloc_path();
140 path->leave_spinning = 1;
142 key.objectid = btrfs_ino(inode);
144 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
145 datasize = btrfs_file_extent_calc_inline_size(cur_size);
147 inode_add_bytes(inode, size);
148 ret = btrfs_insert_empty_item(trans, root, path, &key,
155 leaf = path->nodes[0];
156 ei = btrfs_item_ptr(leaf, path->slots[0],
157 struct btrfs_file_extent_item);
158 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
159 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
160 btrfs_set_file_extent_encryption(leaf, ei, 0);
161 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
162 btrfs_set_file_extent_ram_bytes(leaf, ei, size);
163 ptr = btrfs_file_extent_inline_start(ei);
165 if (compress_type != BTRFS_COMPRESS_NONE) {
168 while (compressed_size > 0) {
169 cpage = compressed_pages[i];
170 cur_size = min_t(unsigned long, compressed_size,
173 kaddr = kmap_atomic(cpage, KM_USER0);
174 write_extent_buffer(leaf, kaddr, ptr, cur_size);
175 kunmap_atomic(kaddr, KM_USER0);
179 compressed_size -= cur_size;
181 btrfs_set_file_extent_compression(leaf, ei,
184 page = find_get_page(inode->i_mapping,
185 start >> PAGE_CACHE_SHIFT);
186 btrfs_set_file_extent_compression(leaf, ei, 0);
187 kaddr = kmap_atomic(page, KM_USER0);
188 offset = start & (PAGE_CACHE_SIZE - 1);
189 write_extent_buffer(leaf, kaddr + offset, ptr, size);
190 kunmap_atomic(kaddr, KM_USER0);
191 page_cache_release(page);
193 btrfs_mark_buffer_dirty(leaf);
194 btrfs_free_path(path);
197 * we're an inline extent, so nobody can
198 * extend the file past i_size without locking
199 * a page we already have locked.
201 * We must do any isize and inode updates
202 * before we unlock the pages. Otherwise we
203 * could end up racing with unlink.
205 BTRFS_I(inode)->disk_i_size = inode->i_size;
206 btrfs_update_inode(trans, root, inode);
210 btrfs_free_path(path);
216 * conditionally insert an inline extent into the file. This
217 * does the checks required to make sure the data is small enough
218 * to fit as an inline extent.
220 static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans,
221 struct btrfs_root *root,
222 struct inode *inode, u64 start, u64 end,
223 size_t compressed_size, int compress_type,
224 struct page **compressed_pages)
226 u64 isize = i_size_read(inode);
227 u64 actual_end = min(end + 1, isize);
228 u64 inline_len = actual_end - start;
229 u64 aligned_end = (end + root->sectorsize - 1) &
230 ~((u64)root->sectorsize - 1);
232 u64 data_len = inline_len;
236 data_len = compressed_size;
239 actual_end >= PAGE_CACHE_SIZE ||
240 data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
242 (actual_end & (root->sectorsize - 1)) == 0) ||
244 data_len > root->fs_info->max_inline) {
248 ret = btrfs_drop_extents(trans, inode, start, aligned_end,
252 if (isize > actual_end)
253 inline_len = min_t(u64, isize, actual_end);
254 ret = insert_inline_extent(trans, root, inode, start,
255 inline_len, compressed_size,
256 compress_type, compressed_pages);
258 btrfs_delalloc_release_metadata(inode, end + 1 - start);
259 btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0);
263 struct async_extent {
268 unsigned long nr_pages;
270 struct list_head list;
275 struct btrfs_root *root;
276 struct page *locked_page;
279 struct list_head extents;
280 struct btrfs_work work;
283 static noinline int add_async_extent(struct async_cow *cow,
284 u64 start, u64 ram_size,
287 unsigned long nr_pages,
290 struct async_extent *async_extent;
292 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
293 BUG_ON(!async_extent);
294 async_extent->start = start;
295 async_extent->ram_size = ram_size;
296 async_extent->compressed_size = compressed_size;
297 async_extent->pages = pages;
298 async_extent->nr_pages = nr_pages;
299 async_extent->compress_type = compress_type;
300 list_add_tail(&async_extent->list, &cow->extents);
305 * we create compressed extents in two phases. The first
306 * phase compresses a range of pages that have already been
307 * locked (both pages and state bits are locked).
309 * This is done inside an ordered work queue, and the compression
310 * is spread across many cpus. The actual IO submission is step
311 * two, and the ordered work queue takes care of making sure that
312 * happens in the same order things were put onto the queue by
313 * writepages and friends.
315 * If this code finds it can't get good compression, it puts an
316 * entry onto the work queue to write the uncompressed bytes. This
317 * makes sure that both compressed inodes and uncompressed inodes
318 * are written in the same order that pdflush sent them down.
320 static noinline int compress_file_range(struct inode *inode,
321 struct page *locked_page,
323 struct async_cow *async_cow,
326 struct btrfs_root *root = BTRFS_I(inode)->root;
327 struct btrfs_trans_handle *trans;
329 u64 blocksize = root->sectorsize;
331 u64 isize = i_size_read(inode);
333 struct page **pages = NULL;
334 unsigned long nr_pages;
335 unsigned long nr_pages_ret = 0;
336 unsigned long total_compressed = 0;
337 unsigned long total_in = 0;
338 unsigned long max_compressed = 128 * 1024;
339 unsigned long max_uncompressed = 128 * 1024;
342 int compress_type = root->fs_info->compress_type;
344 /* if this is a small write inside eof, kick off a defragbot */
345 if (end <= BTRFS_I(inode)->disk_i_size && (end - start + 1) < 16 * 1024)
346 btrfs_add_inode_defrag(NULL, inode);
348 actual_end = min_t(u64, isize, end + 1);
351 nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1;
352 nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE);
355 * we don't want to send crud past the end of i_size through
356 * compression, that's just a waste of CPU time. So, if the
357 * end of the file is before the start of our current
358 * requested range of bytes, we bail out to the uncompressed
359 * cleanup code that can deal with all of this.
361 * It isn't really the fastest way to fix things, but this is a
362 * very uncommon corner.
364 if (actual_end <= start)
365 goto cleanup_and_bail_uncompressed;
367 total_compressed = actual_end - start;
369 /* we want to make sure that amount of ram required to uncompress
370 * an extent is reasonable, so we limit the total size in ram
371 * of a compressed extent to 128k. This is a crucial number
372 * because it also controls how easily we can spread reads across
373 * cpus for decompression.
375 * We also want to make sure the amount of IO required to do
376 * a random read is reasonably small, so we limit the size of
377 * a compressed extent to 128k.
379 total_compressed = min(total_compressed, max_uncompressed);
380 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
381 num_bytes = max(blocksize, num_bytes);
386 * we do compression for mount -o compress and when the
387 * inode has not been flagged as nocompress. This flag can
388 * change at any time if we discover bad compression ratios.
390 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) &&
391 (btrfs_test_opt(root, COMPRESS) ||
392 (BTRFS_I(inode)->force_compress) ||
393 (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))) {
395 pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
398 if (BTRFS_I(inode)->force_compress)
399 compress_type = BTRFS_I(inode)->force_compress;
401 ret = btrfs_compress_pages(compress_type,
402 inode->i_mapping, start,
403 total_compressed, pages,
404 nr_pages, &nr_pages_ret,
410 unsigned long offset = total_compressed &
411 (PAGE_CACHE_SIZE - 1);
412 struct page *page = pages[nr_pages_ret - 1];
415 /* zero the tail end of the last page, we might be
416 * sending it down to disk
419 kaddr = kmap_atomic(page, KM_USER0);
420 memset(kaddr + offset, 0,
421 PAGE_CACHE_SIZE - offset);
422 kunmap_atomic(kaddr, KM_USER0);
428 trans = btrfs_join_transaction(root);
429 BUG_ON(IS_ERR(trans));
430 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
432 /* lets try to make an inline extent */
433 if (ret || total_in < (actual_end - start)) {
434 /* we didn't compress the entire range, try
435 * to make an uncompressed inline extent.
437 ret = cow_file_range_inline(trans, root, inode,
438 start, end, 0, 0, NULL);
440 /* try making a compressed inline extent */
441 ret = cow_file_range_inline(trans, root, inode,
444 compress_type, pages);
448 * inline extent creation worked, we don't need
449 * to create any more async work items. Unlock
450 * and free up our temp pages.
452 extent_clear_unlock_delalloc(inode,
453 &BTRFS_I(inode)->io_tree,
455 EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
456 EXTENT_CLEAR_DELALLOC |
457 EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK);
459 btrfs_end_transaction(trans, root);
462 btrfs_end_transaction(trans, root);
467 * we aren't doing an inline extent round the compressed size
468 * up to a block size boundary so the allocator does sane
471 total_compressed = (total_compressed + blocksize - 1) &
475 * one last check to make sure the compression is really a
476 * win, compare the page count read with the blocks on disk
478 total_in = (total_in + PAGE_CACHE_SIZE - 1) &
479 ~(PAGE_CACHE_SIZE - 1);
480 if (total_compressed >= total_in) {
483 num_bytes = total_in;
486 if (!will_compress && pages) {
488 * the compression code ran but failed to make things smaller,
489 * free any pages it allocated and our page pointer array
491 for (i = 0; i < nr_pages_ret; i++) {
492 WARN_ON(pages[i]->mapping);
493 page_cache_release(pages[i]);
497 total_compressed = 0;
500 /* flag the file so we don't compress in the future */
501 if (!btrfs_test_opt(root, FORCE_COMPRESS) &&
502 !(BTRFS_I(inode)->force_compress)) {
503 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
509 /* the async work queues will take care of doing actual
510 * allocation on disk for these compressed pages,
511 * and will submit them to the elevator.
513 add_async_extent(async_cow, start, num_bytes,
514 total_compressed, pages, nr_pages_ret,
517 if (start + num_bytes < end) {
524 cleanup_and_bail_uncompressed:
526 * No compression, but we still need to write the pages in
527 * the file we've been given so far. redirty the locked
528 * page if it corresponds to our extent and set things up
529 * for the async work queue to run cow_file_range to do
530 * the normal delalloc dance
532 if (page_offset(locked_page) >= start &&
533 page_offset(locked_page) <= end) {
534 __set_page_dirty_nobuffers(locked_page);
535 /* unlocked later on in the async handlers */
537 add_async_extent(async_cow, start, end - start + 1,
538 0, NULL, 0, BTRFS_COMPRESS_NONE);
546 for (i = 0; i < nr_pages_ret; i++) {
547 WARN_ON(pages[i]->mapping);
548 page_cache_release(pages[i]);
556 * phase two of compressed writeback. This is the ordered portion
557 * of the code, which only gets called in the order the work was
558 * queued. We walk all the async extents created by compress_file_range
559 * and send them down to the disk.
561 static noinline int submit_compressed_extents(struct inode *inode,
562 struct async_cow *async_cow)
564 struct async_extent *async_extent;
566 struct btrfs_trans_handle *trans;
567 struct btrfs_key ins;
568 struct extent_map *em;
569 struct btrfs_root *root = BTRFS_I(inode)->root;
570 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
571 struct extent_io_tree *io_tree;
574 if (list_empty(&async_cow->extents))
578 while (!list_empty(&async_cow->extents)) {
579 async_extent = list_entry(async_cow->extents.next,
580 struct async_extent, list);
581 list_del(&async_extent->list);
583 io_tree = &BTRFS_I(inode)->io_tree;
586 /* did the compression code fall back to uncompressed IO? */
587 if (!async_extent->pages) {
588 int page_started = 0;
589 unsigned long nr_written = 0;
591 lock_extent(io_tree, async_extent->start,
592 async_extent->start +
593 async_extent->ram_size - 1, GFP_NOFS);
595 /* allocate blocks */
596 ret = cow_file_range(inode, async_cow->locked_page,
598 async_extent->start +
599 async_extent->ram_size - 1,
600 &page_started, &nr_written, 0);
603 * if page_started, cow_file_range inserted an
604 * inline extent and took care of all the unlocking
605 * and IO for us. Otherwise, we need to submit
606 * all those pages down to the drive.
608 if (!page_started && !ret)
609 extent_write_locked_range(io_tree,
610 inode, async_extent->start,
611 async_extent->start +
612 async_extent->ram_size - 1,
620 lock_extent(io_tree, async_extent->start,
621 async_extent->start + async_extent->ram_size - 1,
624 trans = btrfs_join_transaction(root);
625 BUG_ON(IS_ERR(trans));
626 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
627 ret = btrfs_reserve_extent(trans, root,
628 async_extent->compressed_size,
629 async_extent->compressed_size,
632 btrfs_end_transaction(trans, root);
636 for (i = 0; i < async_extent->nr_pages; i++) {
637 WARN_ON(async_extent->pages[i]->mapping);
638 page_cache_release(async_extent->pages[i]);
640 kfree(async_extent->pages);
641 async_extent->nr_pages = 0;
642 async_extent->pages = NULL;
643 unlock_extent(io_tree, async_extent->start,
644 async_extent->start +
645 async_extent->ram_size - 1, GFP_NOFS);
650 * here we're doing allocation and writeback of the
653 btrfs_drop_extent_cache(inode, async_extent->start,
654 async_extent->start +
655 async_extent->ram_size - 1, 0);
657 em = alloc_extent_map();
659 em->start = async_extent->start;
660 em->len = async_extent->ram_size;
661 em->orig_start = em->start;
663 em->block_start = ins.objectid;
664 em->block_len = ins.offset;
665 em->bdev = root->fs_info->fs_devices->latest_bdev;
666 em->compress_type = async_extent->compress_type;
667 set_bit(EXTENT_FLAG_PINNED, &em->flags);
668 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
671 write_lock(&em_tree->lock);
672 ret = add_extent_mapping(em_tree, em);
673 write_unlock(&em_tree->lock);
674 if (ret != -EEXIST) {
678 btrfs_drop_extent_cache(inode, async_extent->start,
679 async_extent->start +
680 async_extent->ram_size - 1, 0);
683 ret = btrfs_add_ordered_extent_compress(inode,
686 async_extent->ram_size,
688 BTRFS_ORDERED_COMPRESSED,
689 async_extent->compress_type);
693 * clear dirty, set writeback and unlock the pages.
695 extent_clear_unlock_delalloc(inode,
696 &BTRFS_I(inode)->io_tree,
698 async_extent->start +
699 async_extent->ram_size - 1,
700 NULL, EXTENT_CLEAR_UNLOCK_PAGE |
701 EXTENT_CLEAR_UNLOCK |
702 EXTENT_CLEAR_DELALLOC |
703 EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK);
705 ret = btrfs_submit_compressed_write(inode,
707 async_extent->ram_size,
709 ins.offset, async_extent->pages,
710 async_extent->nr_pages);
713 alloc_hint = ins.objectid + ins.offset;
721 static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
724 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
725 struct extent_map *em;
728 read_lock(&em_tree->lock);
729 em = search_extent_mapping(em_tree, start, num_bytes);
732 * if block start isn't an actual block number then find the
733 * first block in this inode and use that as a hint. If that
734 * block is also bogus then just don't worry about it.
736 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
738 em = search_extent_mapping(em_tree, 0, 0);
739 if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
740 alloc_hint = em->block_start;
744 alloc_hint = em->block_start;
748 read_unlock(&em_tree->lock);
754 * when extent_io.c finds a delayed allocation range in the file,
755 * the call backs end up in this code. The basic idea is to
756 * allocate extents on disk for the range, and create ordered data structs
757 * in ram to track those extents.
759 * locked_page is the page that writepage had locked already. We use
760 * it to make sure we don't do extra locks or unlocks.
762 * *page_started is set to one if we unlock locked_page and do everything
763 * required to start IO on it. It may be clean and already done with
766 static noinline int cow_file_range(struct inode *inode,
767 struct page *locked_page,
768 u64 start, u64 end, int *page_started,
769 unsigned long *nr_written,
772 struct btrfs_root *root = BTRFS_I(inode)->root;
773 struct btrfs_trans_handle *trans;
776 unsigned long ram_size;
779 u64 blocksize = root->sectorsize;
780 struct btrfs_key ins;
781 struct extent_map *em;
782 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
785 BUG_ON(btrfs_is_free_space_inode(root, inode));
786 trans = btrfs_join_transaction(root);
787 BUG_ON(IS_ERR(trans));
788 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
790 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
791 num_bytes = max(blocksize, num_bytes);
792 disk_num_bytes = num_bytes;
795 /* if this is a small write inside eof, kick off defrag */
796 if (end <= BTRFS_I(inode)->disk_i_size && num_bytes < 64 * 1024)
797 btrfs_add_inode_defrag(trans, inode);
800 /* lets try to make an inline extent */
801 ret = cow_file_range_inline(trans, root, inode,
802 start, end, 0, 0, NULL);
804 extent_clear_unlock_delalloc(inode,
805 &BTRFS_I(inode)->io_tree,
807 EXTENT_CLEAR_UNLOCK_PAGE |
808 EXTENT_CLEAR_UNLOCK |
809 EXTENT_CLEAR_DELALLOC |
811 EXTENT_SET_WRITEBACK |
812 EXTENT_END_WRITEBACK);
814 *nr_written = *nr_written +
815 (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
822 BUG_ON(disk_num_bytes >
823 btrfs_super_total_bytes(&root->fs_info->super_copy));
825 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
826 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
828 while (disk_num_bytes > 0) {
831 cur_alloc_size = disk_num_bytes;
832 ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
833 root->sectorsize, 0, alloc_hint,
837 em = alloc_extent_map();
840 em->orig_start = em->start;
841 ram_size = ins.offset;
842 em->len = ins.offset;
844 em->block_start = ins.objectid;
845 em->block_len = ins.offset;
846 em->bdev = root->fs_info->fs_devices->latest_bdev;
847 set_bit(EXTENT_FLAG_PINNED, &em->flags);
850 write_lock(&em_tree->lock);
851 ret = add_extent_mapping(em_tree, em);
852 write_unlock(&em_tree->lock);
853 if (ret != -EEXIST) {
857 btrfs_drop_extent_cache(inode, start,
858 start + ram_size - 1, 0);
861 cur_alloc_size = ins.offset;
862 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
863 ram_size, cur_alloc_size, 0);
866 if (root->root_key.objectid ==
867 BTRFS_DATA_RELOC_TREE_OBJECTID) {
868 ret = btrfs_reloc_clone_csums(inode, start,
873 if (disk_num_bytes < cur_alloc_size)
876 /* we're not doing compressed IO, don't unlock the first
877 * page (which the caller expects to stay locked), don't
878 * clear any dirty bits and don't set any writeback bits
880 * Do set the Private2 bit so we know this page was properly
881 * setup for writepage
883 op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0;
884 op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
887 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
888 start, start + ram_size - 1,
890 disk_num_bytes -= cur_alloc_size;
891 num_bytes -= cur_alloc_size;
892 alloc_hint = ins.objectid + ins.offset;
893 start += cur_alloc_size;
897 btrfs_end_transaction(trans, root);
903 * work queue call back to started compression on a file and pages
905 static noinline void async_cow_start(struct btrfs_work *work)
907 struct async_cow *async_cow;
909 async_cow = container_of(work, struct async_cow, work);
911 compress_file_range(async_cow->inode, async_cow->locked_page,
912 async_cow->start, async_cow->end, async_cow,
915 async_cow->inode = NULL;
919 * work queue call back to submit previously compressed pages
921 static noinline void async_cow_submit(struct btrfs_work *work)
923 struct async_cow *async_cow;
924 struct btrfs_root *root;
925 unsigned long nr_pages;
927 async_cow = container_of(work, struct async_cow, work);
929 root = async_cow->root;
930 nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >>
933 atomic_sub(nr_pages, &root->fs_info->async_delalloc_pages);
935 if (atomic_read(&root->fs_info->async_delalloc_pages) <
937 waitqueue_active(&root->fs_info->async_submit_wait))
938 wake_up(&root->fs_info->async_submit_wait);
940 if (async_cow->inode)
941 submit_compressed_extents(async_cow->inode, async_cow);
944 static noinline void async_cow_free(struct btrfs_work *work)
946 struct async_cow *async_cow;
947 async_cow = container_of(work, struct async_cow, work);
951 static int cow_file_range_async(struct inode *inode, struct page *locked_page,
952 u64 start, u64 end, int *page_started,
953 unsigned long *nr_written)
955 struct async_cow *async_cow;
956 struct btrfs_root *root = BTRFS_I(inode)->root;
957 unsigned long nr_pages;
959 int limit = 10 * 1024 * 1042;
961 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
962 1, 0, NULL, GFP_NOFS);
963 while (start < end) {
964 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
966 async_cow->inode = inode;
967 async_cow->root = root;
968 async_cow->locked_page = locked_page;
969 async_cow->start = start;
971 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
974 cur_end = min(end, start + 512 * 1024 - 1);
976 async_cow->end = cur_end;
977 INIT_LIST_HEAD(&async_cow->extents);
979 async_cow->work.func = async_cow_start;
980 async_cow->work.ordered_func = async_cow_submit;
981 async_cow->work.ordered_free = async_cow_free;
982 async_cow->work.flags = 0;
984 nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >>
986 atomic_add(nr_pages, &root->fs_info->async_delalloc_pages);
988 btrfs_queue_worker(&root->fs_info->delalloc_workers,
991 if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) {
992 wait_event(root->fs_info->async_submit_wait,
993 (atomic_read(&root->fs_info->async_delalloc_pages) <
997 while (atomic_read(&root->fs_info->async_submit_draining) &&
998 atomic_read(&root->fs_info->async_delalloc_pages)) {
999 wait_event(root->fs_info->async_submit_wait,
1000 (atomic_read(&root->fs_info->async_delalloc_pages) ==
1004 *nr_written += nr_pages;
1005 start = cur_end + 1;
1011 static noinline int csum_exist_in_range(struct btrfs_root *root,
1012 u64 bytenr, u64 num_bytes)
1015 struct btrfs_ordered_sum *sums;
1018 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr,
1019 bytenr + num_bytes - 1, &list, 0);
1020 if (ret == 0 && list_empty(&list))
1023 while (!list_empty(&list)) {
1024 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
1025 list_del(&sums->list);
1032 * when nowcow writeback call back. This checks for snapshots or COW copies
1033 * of the extents that exist in the file, and COWs the file as required.
1035 * If no cow copies or snapshots exist, we write directly to the existing
1038 static noinline int run_delalloc_nocow(struct inode *inode,
1039 struct page *locked_page,
1040 u64 start, u64 end, int *page_started, int force,
1041 unsigned long *nr_written)
1043 struct btrfs_root *root = BTRFS_I(inode)->root;
1044 struct btrfs_trans_handle *trans;
1045 struct extent_buffer *leaf;
1046 struct btrfs_path *path;
1047 struct btrfs_file_extent_item *fi;
1048 struct btrfs_key found_key;
1061 u64 ino = btrfs_ino(inode);
1063 path = btrfs_alloc_path();
1067 nolock = btrfs_is_free_space_inode(root, inode);
1070 trans = btrfs_join_transaction_nolock(root);
1072 trans = btrfs_join_transaction(root);
1074 BUG_ON(IS_ERR(trans));
1075 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1077 cow_start = (u64)-1;
1080 ret = btrfs_lookup_file_extent(trans, root, path, ino,
1083 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1084 leaf = path->nodes[0];
1085 btrfs_item_key_to_cpu(leaf, &found_key,
1086 path->slots[0] - 1);
1087 if (found_key.objectid == ino &&
1088 found_key.type == BTRFS_EXTENT_DATA_KEY)
1093 leaf = path->nodes[0];
1094 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1095 ret = btrfs_next_leaf(root, path);
1100 leaf = path->nodes[0];
1106 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1108 if (found_key.objectid > ino ||
1109 found_key.type > BTRFS_EXTENT_DATA_KEY ||
1110 found_key.offset > end)
1113 if (found_key.offset > cur_offset) {
1114 extent_end = found_key.offset;
1119 fi = btrfs_item_ptr(leaf, path->slots[0],
1120 struct btrfs_file_extent_item);
1121 extent_type = btrfs_file_extent_type(leaf, fi);
1123 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1124 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1125 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1126 extent_offset = btrfs_file_extent_offset(leaf, fi);
1127 extent_end = found_key.offset +
1128 btrfs_file_extent_num_bytes(leaf, fi);
1129 if (extent_end <= start) {
1133 if (disk_bytenr == 0)
1135 if (btrfs_file_extent_compression(leaf, fi) ||
1136 btrfs_file_extent_encryption(leaf, fi) ||
1137 btrfs_file_extent_other_encoding(leaf, fi))
1139 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1141 if (btrfs_extent_readonly(root, disk_bytenr))
1143 if (btrfs_cross_ref_exist(trans, root, ino,
1145 extent_offset, disk_bytenr))
1147 disk_bytenr += extent_offset;
1148 disk_bytenr += cur_offset - found_key.offset;
1149 num_bytes = min(end + 1, extent_end) - cur_offset;
1151 * force cow if csum exists in the range.
1152 * this ensure that csum for a given extent are
1153 * either valid or do not exist.
1155 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
1158 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1159 extent_end = found_key.offset +
1160 btrfs_file_extent_inline_len(leaf, fi);
1161 extent_end = ALIGN(extent_end, root->sectorsize);
1166 if (extent_end <= start) {
1171 if (cow_start == (u64)-1)
1172 cow_start = cur_offset;
1173 cur_offset = extent_end;
1174 if (cur_offset > end)
1180 btrfs_release_path(path);
1181 if (cow_start != (u64)-1) {
1182 ret = cow_file_range(inode, locked_page, cow_start,
1183 found_key.offset - 1, page_started,
1186 cow_start = (u64)-1;
1189 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1190 struct extent_map *em;
1191 struct extent_map_tree *em_tree;
1192 em_tree = &BTRFS_I(inode)->extent_tree;
1193 em = alloc_extent_map();
1195 em->start = cur_offset;
1196 em->orig_start = em->start;
1197 em->len = num_bytes;
1198 em->block_len = num_bytes;
1199 em->block_start = disk_bytenr;
1200 em->bdev = root->fs_info->fs_devices->latest_bdev;
1201 set_bit(EXTENT_FLAG_PINNED, &em->flags);
1203 write_lock(&em_tree->lock);
1204 ret = add_extent_mapping(em_tree, em);
1205 write_unlock(&em_tree->lock);
1206 if (ret != -EEXIST) {
1207 free_extent_map(em);
1210 btrfs_drop_extent_cache(inode, em->start,
1211 em->start + em->len - 1, 0);
1213 type = BTRFS_ORDERED_PREALLOC;
1215 type = BTRFS_ORDERED_NOCOW;
1218 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr,
1219 num_bytes, num_bytes, type);
1222 if (root->root_key.objectid ==
1223 BTRFS_DATA_RELOC_TREE_OBJECTID) {
1224 ret = btrfs_reloc_clone_csums(inode, cur_offset,
1229 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
1230 cur_offset, cur_offset + num_bytes - 1,
1231 locked_page, EXTENT_CLEAR_UNLOCK_PAGE |
1232 EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
1233 EXTENT_SET_PRIVATE2);
1234 cur_offset = extent_end;
1235 if (cur_offset > end)
1238 btrfs_release_path(path);
1240 if (cur_offset <= end && cow_start == (u64)-1)
1241 cow_start = cur_offset;
1242 if (cow_start != (u64)-1) {
1243 ret = cow_file_range(inode, locked_page, cow_start, end,
1244 page_started, nr_written, 1);
1249 ret = btrfs_end_transaction_nolock(trans, root);
1252 ret = btrfs_end_transaction(trans, root);
1255 btrfs_free_path(path);
1260 * extent_io.c call back to do delayed allocation processing
1262 static int run_delalloc_range(struct inode *inode, struct page *locked_page,
1263 u64 start, u64 end, int *page_started,
1264 unsigned long *nr_written)
1267 struct btrfs_root *root = BTRFS_I(inode)->root;
1269 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW)
1270 ret = run_delalloc_nocow(inode, locked_page, start, end,
1271 page_started, 1, nr_written);
1272 else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)
1273 ret = run_delalloc_nocow(inode, locked_page, start, end,
1274 page_started, 0, nr_written);
1275 else if (!btrfs_test_opt(root, COMPRESS) &&
1276 !(BTRFS_I(inode)->force_compress) &&
1277 !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))
1278 ret = cow_file_range(inode, locked_page, start, end,
1279 page_started, nr_written, 1);
1281 ret = cow_file_range_async(inode, locked_page, start, end,
1282 page_started, nr_written);
1286 static void btrfs_split_extent_hook(struct inode *inode,
1287 struct extent_state *orig, u64 split)
1289 /* not delalloc, ignore it */
1290 if (!(orig->state & EXTENT_DELALLOC))
1293 spin_lock(&BTRFS_I(inode)->lock);
1294 BTRFS_I(inode)->outstanding_extents++;
1295 spin_unlock(&BTRFS_I(inode)->lock);
1299 * extent_io.c merge_extent_hook, used to track merged delayed allocation
1300 * extents so we can keep track of new extents that are just merged onto old
1301 * extents, such as when we are doing sequential writes, so we can properly
1302 * account for the metadata space we'll need.
1304 static void btrfs_merge_extent_hook(struct inode *inode,
1305 struct extent_state *new,
1306 struct extent_state *other)
1308 /* not delalloc, ignore it */
1309 if (!(other->state & EXTENT_DELALLOC))
1312 spin_lock(&BTRFS_I(inode)->lock);
1313 BTRFS_I(inode)->outstanding_extents--;
1314 spin_unlock(&BTRFS_I(inode)->lock);
1318 * extent_io.c set_bit_hook, used to track delayed allocation
1319 * bytes in this file, and to maintain the list of inodes that
1320 * have pending delalloc work to be done.
1322 static void btrfs_set_bit_hook(struct inode *inode,
1323 struct extent_state *state, int *bits)
1327 * set_bit and clear bit hooks normally require _irqsave/restore
1328 * but in this case, we are only testing for the DELALLOC
1329 * bit, which is only set or cleared with irqs on
1331 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1332 struct btrfs_root *root = BTRFS_I(inode)->root;
1333 u64 len = state->end + 1 - state->start;
1334 bool do_list = !btrfs_is_free_space_inode(root, inode);
1336 if (*bits & EXTENT_FIRST_DELALLOC) {
1337 *bits &= ~EXTENT_FIRST_DELALLOC;
1339 spin_lock(&BTRFS_I(inode)->lock);
1340 BTRFS_I(inode)->outstanding_extents++;
1341 spin_unlock(&BTRFS_I(inode)->lock);
1344 spin_lock(&root->fs_info->delalloc_lock);
1345 BTRFS_I(inode)->delalloc_bytes += len;
1346 root->fs_info->delalloc_bytes += len;
1347 if (do_list && list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1348 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1349 &root->fs_info->delalloc_inodes);
1351 spin_unlock(&root->fs_info->delalloc_lock);
1356 * extent_io.c clear_bit_hook, see set_bit_hook for why
1358 static void btrfs_clear_bit_hook(struct inode *inode,
1359 struct extent_state *state, int *bits)
1362 * set_bit and clear bit hooks normally require _irqsave/restore
1363 * but in this case, we are only testing for the DELALLOC
1364 * bit, which is only set or cleared with irqs on
1366 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1367 struct btrfs_root *root = BTRFS_I(inode)->root;
1368 u64 len = state->end + 1 - state->start;
1369 bool do_list = !btrfs_is_free_space_inode(root, inode);
1371 if (*bits & EXTENT_FIRST_DELALLOC) {
1372 *bits &= ~EXTENT_FIRST_DELALLOC;
1373 } else if (!(*bits & EXTENT_DO_ACCOUNTING)) {
1374 spin_lock(&BTRFS_I(inode)->lock);
1375 BTRFS_I(inode)->outstanding_extents--;
1376 spin_unlock(&BTRFS_I(inode)->lock);
1379 if (*bits & EXTENT_DO_ACCOUNTING)
1380 btrfs_delalloc_release_metadata(inode, len);
1382 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
1384 btrfs_free_reserved_data_space(inode, len);
1386 spin_lock(&root->fs_info->delalloc_lock);
1387 root->fs_info->delalloc_bytes -= len;
1388 BTRFS_I(inode)->delalloc_bytes -= len;
1390 if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 &&
1391 !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1392 list_del_init(&BTRFS_I(inode)->delalloc_inodes);
1394 spin_unlock(&root->fs_info->delalloc_lock);
1399 * extent_io.c merge_bio_hook, this must check the chunk tree to make sure
1400 * we don't create bios that span stripes or chunks
1402 int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
1403 size_t size, struct bio *bio,
1404 unsigned long bio_flags)
1406 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
1407 struct btrfs_mapping_tree *map_tree;
1408 u64 logical = (u64)bio->bi_sector << 9;
1413 if (bio_flags & EXTENT_BIO_COMPRESSED)
1416 length = bio->bi_size;
1417 map_tree = &root->fs_info->mapping_tree;
1418 map_length = length;
1419 ret = btrfs_map_block(map_tree, READ, logical,
1420 &map_length, NULL, 0);
1422 if (map_length < length + size)
1428 * in order to insert checksums into the metadata in large chunks,
1429 * we wait until bio submission time. All the pages in the bio are
1430 * checksummed and sums are attached onto the ordered extent record.
1432 * At IO completion time the cums attached on the ordered extent record
1433 * are inserted into the btree
1435 static int __btrfs_submit_bio_start(struct inode *inode, int rw,
1436 struct bio *bio, int mirror_num,
1437 unsigned long bio_flags,
1440 struct btrfs_root *root = BTRFS_I(inode)->root;
1443 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1449 * in order to insert checksums into the metadata in large chunks,
1450 * we wait until bio submission time. All the pages in the bio are
1451 * checksummed and sums are attached onto the ordered extent record.
1453 * At IO completion time the cums attached on the ordered extent record
1454 * are inserted into the btree
1456 static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
1457 int mirror_num, unsigned long bio_flags,
1460 struct btrfs_root *root = BTRFS_I(inode)->root;
1461 return btrfs_map_bio(root, rw, bio, mirror_num, 1);
1465 * extent_io.c submission hook. This does the right thing for csum calculation
1466 * on write, or reading the csums from the tree before a read
1468 static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
1469 int mirror_num, unsigned long bio_flags,
1472 struct btrfs_root *root = BTRFS_I(inode)->root;
1476 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
1478 if (btrfs_is_free_space_inode(root, inode))
1479 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 2);
1481 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
1484 if (!(rw & REQ_WRITE)) {
1485 if (bio_flags & EXTENT_BIO_COMPRESSED) {
1486 return btrfs_submit_compressed_read(inode, bio,
1487 mirror_num, bio_flags);
1488 } else if (!skip_sum) {
1489 ret = btrfs_lookup_bio_sums(root, inode, bio, NULL);
1494 } else if (!skip_sum) {
1495 /* csum items have already been cloned */
1496 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
1498 /* we're doing a write, do the async checksumming */
1499 return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
1500 inode, rw, bio, mirror_num,
1501 bio_flags, bio_offset,
1502 __btrfs_submit_bio_start,
1503 __btrfs_submit_bio_done);
1507 return btrfs_map_bio(root, rw, bio, mirror_num, 0);
1511 * given a list of ordered sums record them in the inode. This happens
1512 * at IO completion time based on sums calculated at bio submission time.
1514 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
1515 struct inode *inode, u64 file_offset,
1516 struct list_head *list)
1518 struct btrfs_ordered_sum *sum;
1520 list_for_each_entry(sum, list, list) {
1521 btrfs_csum_file_blocks(trans,
1522 BTRFS_I(inode)->root->fs_info->csum_root, sum);
1527 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
1528 struct extent_state **cached_state)
1530 if ((end & (PAGE_CACHE_SIZE - 1)) == 0)
1532 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
1533 cached_state, GFP_NOFS);
1536 /* see btrfs_writepage_start_hook for details on why this is required */
1537 struct btrfs_writepage_fixup {
1539 struct btrfs_work work;
1542 static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
1544 struct btrfs_writepage_fixup *fixup;
1545 struct btrfs_ordered_extent *ordered;
1546 struct extent_state *cached_state = NULL;
1548 struct inode *inode;
1552 fixup = container_of(work, struct btrfs_writepage_fixup, work);
1556 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
1557 ClearPageChecked(page);
1561 inode = page->mapping->host;
1562 page_start = page_offset(page);
1563 page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
1565 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 0,
1566 &cached_state, GFP_NOFS);
1568 /* already ordered? We're done */
1569 if (PagePrivate2(page))
1572 ordered = btrfs_lookup_ordered_extent(inode, page_start);
1574 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start,
1575 page_end, &cached_state, GFP_NOFS);
1577 btrfs_start_ordered_extent(inode, ordered, 1);
1582 btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state);
1583 ClearPageChecked(page);
1585 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
1586 &cached_state, GFP_NOFS);
1589 page_cache_release(page);
1594 * There are a few paths in the higher layers of the kernel that directly
1595 * set the page dirty bit without asking the filesystem if it is a
1596 * good idea. This causes problems because we want to make sure COW
1597 * properly happens and the data=ordered rules are followed.
1599 * In our case any range that doesn't have the ORDERED bit set
1600 * hasn't been properly setup for IO. We kick off an async process
1601 * to fix it up. The async helper will wait for ordered extents, set
1602 * the delalloc bit and make it safe to write the page.
1604 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
1606 struct inode *inode = page->mapping->host;
1607 struct btrfs_writepage_fixup *fixup;
1608 struct btrfs_root *root = BTRFS_I(inode)->root;
1610 /* this page is properly in the ordered list */
1611 if (TestClearPagePrivate2(page))
1614 if (PageChecked(page))
1617 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
1621 SetPageChecked(page);
1622 page_cache_get(page);
1623 fixup->work.func = btrfs_writepage_fixup_worker;
1625 btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
1629 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
1630 struct inode *inode, u64 file_pos,
1631 u64 disk_bytenr, u64 disk_num_bytes,
1632 u64 num_bytes, u64 ram_bytes,
1633 u8 compression, u8 encryption,
1634 u16 other_encoding, int extent_type)
1636 struct btrfs_root *root = BTRFS_I(inode)->root;
1637 struct btrfs_file_extent_item *fi;
1638 struct btrfs_path *path;
1639 struct extent_buffer *leaf;
1640 struct btrfs_key ins;
1644 path = btrfs_alloc_path();
1648 path->leave_spinning = 1;
1651 * we may be replacing one extent in the tree with another.
1652 * The new extent is pinned in the extent map, and we don't want
1653 * to drop it from the cache until it is completely in the btree.
1655 * So, tell btrfs_drop_extents to leave this extent in the cache.
1656 * the caller is expected to unpin it and allow it to be merged
1659 ret = btrfs_drop_extents(trans, inode, file_pos, file_pos + num_bytes,
1663 ins.objectid = btrfs_ino(inode);
1664 ins.offset = file_pos;
1665 ins.type = BTRFS_EXTENT_DATA_KEY;
1666 ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*fi));
1668 leaf = path->nodes[0];
1669 fi = btrfs_item_ptr(leaf, path->slots[0],
1670 struct btrfs_file_extent_item);
1671 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1672 btrfs_set_file_extent_type(leaf, fi, extent_type);
1673 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
1674 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
1675 btrfs_set_file_extent_offset(leaf, fi, 0);
1676 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
1677 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
1678 btrfs_set_file_extent_compression(leaf, fi, compression);
1679 btrfs_set_file_extent_encryption(leaf, fi, encryption);
1680 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
1682 btrfs_unlock_up_safe(path, 1);
1683 btrfs_set_lock_blocking(leaf);
1685 btrfs_mark_buffer_dirty(leaf);
1687 inode_add_bytes(inode, num_bytes);
1689 ins.objectid = disk_bytenr;
1690 ins.offset = disk_num_bytes;
1691 ins.type = BTRFS_EXTENT_ITEM_KEY;
1692 ret = btrfs_alloc_reserved_file_extent(trans, root,
1693 root->root_key.objectid,
1694 btrfs_ino(inode), file_pos, &ins);
1696 btrfs_free_path(path);
1702 * helper function for btrfs_finish_ordered_io, this
1703 * just reads in some of the csum leaves to prime them into ram
1704 * before we start the transaction. It limits the amount of btree
1705 * reads required while inside the transaction.
1707 /* as ordered data IO finishes, this gets called so we can finish
1708 * an ordered extent if the range of bytes in the file it covers are
1711 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
1713 struct btrfs_root *root = BTRFS_I(inode)->root;
1714 struct btrfs_trans_handle *trans = NULL;
1715 struct btrfs_ordered_extent *ordered_extent = NULL;
1716 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1717 struct extent_state *cached_state = NULL;
1718 int compress_type = 0;
1722 ret = btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
1726 BUG_ON(!ordered_extent);
1728 nolock = btrfs_is_free_space_inode(root, inode);
1730 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
1731 BUG_ON(!list_empty(&ordered_extent->list));
1732 ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
1735 trans = btrfs_join_transaction_nolock(root);
1737 trans = btrfs_join_transaction(root);
1738 BUG_ON(IS_ERR(trans));
1739 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1740 ret = btrfs_update_inode(trans, root, inode);
1746 lock_extent_bits(io_tree, ordered_extent->file_offset,
1747 ordered_extent->file_offset + ordered_extent->len - 1,
1748 0, &cached_state, GFP_NOFS);
1751 trans = btrfs_join_transaction_nolock(root);
1753 trans = btrfs_join_transaction(root);
1754 BUG_ON(IS_ERR(trans));
1755 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1757 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
1758 compress_type = ordered_extent->compress_type;
1759 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
1760 BUG_ON(compress_type);
1761 ret = btrfs_mark_extent_written(trans, inode,
1762 ordered_extent->file_offset,
1763 ordered_extent->file_offset +
1764 ordered_extent->len);
1767 BUG_ON(root == root->fs_info->tree_root);
1768 ret = insert_reserved_file_extent(trans, inode,
1769 ordered_extent->file_offset,
1770 ordered_extent->start,
1771 ordered_extent->disk_len,
1772 ordered_extent->len,
1773 ordered_extent->len,
1774 compress_type, 0, 0,
1775 BTRFS_FILE_EXTENT_REG);
1776 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
1777 ordered_extent->file_offset,
1778 ordered_extent->len);
1781 unlock_extent_cached(io_tree, ordered_extent->file_offset,
1782 ordered_extent->file_offset +
1783 ordered_extent->len - 1, &cached_state, GFP_NOFS);
1785 add_pending_csums(trans, inode, ordered_extent->file_offset,
1786 &ordered_extent->list);
1788 ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
1789 if (!ret || !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
1790 ret = btrfs_update_inode(trans, root, inode);
1797 btrfs_end_transaction_nolock(trans, root);
1799 btrfs_delalloc_release_metadata(inode, ordered_extent->len);
1801 btrfs_end_transaction(trans, root);
1805 btrfs_put_ordered_extent(ordered_extent);
1806 /* once for the tree */
1807 btrfs_put_ordered_extent(ordered_extent);
1812 static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
1813 struct extent_state *state, int uptodate)
1815 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate);
1817 ClearPagePrivate2(page);
1818 return btrfs_finish_ordered_io(page->mapping->host, start, end);
1822 * When IO fails, either with EIO or csum verification fails, we
1823 * try other mirrors that might have a good copy of the data. This
1824 * io_failure_record is used to record state as we go through all the
1825 * mirrors. If another mirror has good data, the page is set up to date
1826 * and things continue. If a good mirror can't be found, the original
1827 * bio end_io callback is called to indicate things have failed.
1829 struct io_failure_record {
1834 unsigned long bio_flags;
1838 static int btrfs_io_failed_hook(struct bio *failed_bio,
1839 struct page *page, u64 start, u64 end,
1840 struct extent_state *state)
1842 struct io_failure_record *failrec = NULL;
1844 struct extent_map *em;
1845 struct inode *inode = page->mapping->host;
1846 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
1847 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1854 ret = get_state_private(failure_tree, start, &private);
1856 failrec = kmalloc(sizeof(*failrec), GFP_NOFS);
1859 failrec->start = start;
1860 failrec->len = end - start + 1;
1861 failrec->last_mirror = 0;
1862 failrec->bio_flags = 0;
1864 read_lock(&em_tree->lock);
1865 em = lookup_extent_mapping(em_tree, start, failrec->len);
1866 if (em->start > start || em->start + em->len < start) {
1867 free_extent_map(em);
1870 read_unlock(&em_tree->lock);
1872 if (IS_ERR_OR_NULL(em)) {
1876 logical = start - em->start;
1877 logical = em->block_start + logical;
1878 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
1879 logical = em->block_start;
1880 failrec->bio_flags = EXTENT_BIO_COMPRESSED;
1881 extent_set_compress_type(&failrec->bio_flags,
1884 failrec->logical = logical;
1885 free_extent_map(em);
1886 set_extent_bits(failure_tree, start, end, EXTENT_LOCKED |
1887 EXTENT_DIRTY, GFP_NOFS);
1888 set_state_private(failure_tree, start,
1889 (u64)(unsigned long)failrec);
1891 failrec = (struct io_failure_record *)(unsigned long)private;
1893 num_copies = btrfs_num_copies(
1894 &BTRFS_I(inode)->root->fs_info->mapping_tree,
1895 failrec->logical, failrec->len);
1896 failrec->last_mirror++;
1898 spin_lock(&BTRFS_I(inode)->io_tree.lock);
1899 state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree,
1902 if (state && state->start != failrec->start)
1904 spin_unlock(&BTRFS_I(inode)->io_tree.lock);
1906 if (!state || failrec->last_mirror > num_copies) {
1907 set_state_private(failure_tree, failrec->start, 0);
1908 clear_extent_bits(failure_tree, failrec->start,
1909 failrec->start + failrec->len - 1,
1910 EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
1914 bio = bio_alloc(GFP_NOFS, 1);
1915 bio->bi_private = state;
1916 bio->bi_end_io = failed_bio->bi_end_io;
1917 bio->bi_sector = failrec->logical >> 9;
1918 bio->bi_bdev = failed_bio->bi_bdev;
1921 bio_add_page(bio, page, failrec->len, start - page_offset(page));
1922 if (failed_bio->bi_rw & REQ_WRITE)
1927 ret = BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio,
1928 failrec->last_mirror,
1929 failrec->bio_flags, 0);
1934 * each time an IO finishes, we do a fast check in the IO failure tree
1935 * to see if we need to process or clean up an io_failure_record
1937 static int btrfs_clean_io_failures(struct inode *inode, u64 start)
1940 u64 private_failure;
1941 struct io_failure_record *failure;
1945 if (count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
1946 (u64)-1, 1, EXTENT_DIRTY, 0)) {
1947 ret = get_state_private(&BTRFS_I(inode)->io_failure_tree,
1948 start, &private_failure);
1950 failure = (struct io_failure_record *)(unsigned long)
1952 set_state_private(&BTRFS_I(inode)->io_failure_tree,
1954 clear_extent_bits(&BTRFS_I(inode)->io_failure_tree,
1956 failure->start + failure->len - 1,
1957 EXTENT_DIRTY | EXTENT_LOCKED,
1966 * when reads are done, we need to check csums to verify the data is correct
1967 * if there's a match, we allow the bio to finish. If not, we go through
1968 * the io_failure_record routines to find good copies
1970 static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
1971 struct extent_state *state)
1973 size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
1974 struct inode *inode = page->mapping->host;
1975 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1977 u64 private = ~(u32)0;
1979 struct btrfs_root *root = BTRFS_I(inode)->root;
1982 if (PageChecked(page)) {
1983 ClearPageChecked(page);
1987 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
1990 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
1991 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
1992 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM,
1997 if (state && state->start == start) {
1998 private = state->private;
2001 ret = get_state_private(io_tree, start, &private);
2003 kaddr = kmap_atomic(page, KM_USER0);
2007 csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1);
2008 btrfs_csum_final(csum, (char *)&csum);
2009 if (csum != private)
2012 kunmap_atomic(kaddr, KM_USER0);
2014 /* if the io failure tree for this inode is non-empty,
2015 * check to see if we've recovered from a failed IO
2017 btrfs_clean_io_failures(inode, start);
2021 printk_ratelimited(KERN_INFO "btrfs csum failed ino %llu off %llu csum %u "
2023 (unsigned long long)btrfs_ino(page->mapping->host),
2024 (unsigned long long)start, csum,
2025 (unsigned long long)private);
2026 memset(kaddr + offset, 1, end - start + 1);
2027 flush_dcache_page(page);
2028 kunmap_atomic(kaddr, KM_USER0);
2034 struct delayed_iput {
2035 struct list_head list;
2036 struct inode *inode;
2039 void btrfs_add_delayed_iput(struct inode *inode)
2041 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2042 struct delayed_iput *delayed;
2044 if (atomic_add_unless(&inode->i_count, -1, 1))
2047 delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL);
2048 delayed->inode = inode;
2050 spin_lock(&fs_info->delayed_iput_lock);
2051 list_add_tail(&delayed->list, &fs_info->delayed_iputs);
2052 spin_unlock(&fs_info->delayed_iput_lock);
2055 void btrfs_run_delayed_iputs(struct btrfs_root *root)
2058 struct btrfs_fs_info *fs_info = root->fs_info;
2059 struct delayed_iput *delayed;
2062 spin_lock(&fs_info->delayed_iput_lock);
2063 empty = list_empty(&fs_info->delayed_iputs);
2064 spin_unlock(&fs_info->delayed_iput_lock);
2068 down_read(&root->fs_info->cleanup_work_sem);
2069 spin_lock(&fs_info->delayed_iput_lock);
2070 list_splice_init(&fs_info->delayed_iputs, &list);
2071 spin_unlock(&fs_info->delayed_iput_lock);
2073 while (!list_empty(&list)) {
2074 delayed = list_entry(list.next, struct delayed_iput, list);
2075 list_del(&delayed->list);
2076 iput(delayed->inode);
2079 up_read(&root->fs_info->cleanup_work_sem);
2082 enum btrfs_orphan_cleanup_state {
2083 ORPHAN_CLEANUP_STARTED = 1,
2084 ORPHAN_CLEANUP_DONE = 2,
2088 * This is called in transaction commmit time. If there are no orphan
2089 * files in the subvolume, it removes orphan item and frees block_rsv
2092 void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans,
2093 struct btrfs_root *root)
2097 if (!list_empty(&root->orphan_list) ||
2098 root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE)
2101 if (root->orphan_item_inserted &&
2102 btrfs_root_refs(&root->root_item) > 0) {
2103 ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root,
2104 root->root_key.objectid);
2106 root->orphan_item_inserted = 0;
2109 if (root->orphan_block_rsv) {
2110 WARN_ON(root->orphan_block_rsv->size > 0);
2111 btrfs_free_block_rsv(root, root->orphan_block_rsv);
2112 root->orphan_block_rsv = NULL;
2117 * This creates an orphan entry for the given inode in case something goes
2118 * wrong in the middle of an unlink/truncate.
2120 * NOTE: caller of this function should reserve 5 units of metadata for
2123 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
2125 struct btrfs_root *root = BTRFS_I(inode)->root;
2126 struct btrfs_block_rsv *block_rsv = NULL;
2131 if (!root->orphan_block_rsv) {
2132 block_rsv = btrfs_alloc_block_rsv(root);
2137 spin_lock(&root->orphan_lock);
2138 if (!root->orphan_block_rsv) {
2139 root->orphan_block_rsv = block_rsv;
2140 } else if (block_rsv) {
2141 btrfs_free_block_rsv(root, block_rsv);
2145 if (list_empty(&BTRFS_I(inode)->i_orphan)) {
2146 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
2149 * For proper ENOSPC handling, we should do orphan
2150 * cleanup when mounting. But this introduces backward
2151 * compatibility issue.
2153 if (!xchg(&root->orphan_item_inserted, 1))
2161 if (!BTRFS_I(inode)->orphan_meta_reserved) {
2162 BTRFS_I(inode)->orphan_meta_reserved = 1;
2165 spin_unlock(&root->orphan_lock);
2167 /* grab metadata reservation from transaction handle */
2169 ret = btrfs_orphan_reserve_metadata(trans, inode);
2173 /* insert an orphan item to track this unlinked/truncated file */
2175 ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode));
2179 /* insert an orphan item to track subvolume contains orphan files */
2181 ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
2182 root->root_key.objectid);
2189 * We have done the truncate/delete so we can go ahead and remove the orphan
2190 * item for this particular inode.
2192 int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode)
2194 struct btrfs_root *root = BTRFS_I(inode)->root;
2195 int delete_item = 0;
2196 int release_rsv = 0;
2199 spin_lock(&root->orphan_lock);
2200 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
2201 list_del_init(&BTRFS_I(inode)->i_orphan);
2205 if (BTRFS_I(inode)->orphan_meta_reserved) {
2206 BTRFS_I(inode)->orphan_meta_reserved = 0;
2209 spin_unlock(&root->orphan_lock);
2211 if (trans && delete_item) {
2212 ret = btrfs_del_orphan_item(trans, root, btrfs_ino(inode));
2217 btrfs_orphan_release_metadata(inode);
2223 * this cleans up any orphans that may be left on the list from the last use
2226 int btrfs_orphan_cleanup(struct btrfs_root *root)
2228 struct btrfs_path *path;
2229 struct extent_buffer *leaf;
2230 struct btrfs_key key, found_key;
2231 struct btrfs_trans_handle *trans;
2232 struct inode *inode;
2233 int ret = 0, nr_unlink = 0, nr_truncate = 0;
2235 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
2238 path = btrfs_alloc_path();
2245 key.objectid = BTRFS_ORPHAN_OBJECTID;
2246 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
2247 key.offset = (u64)-1;
2250 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2255 * if ret == 0 means we found what we were searching for, which
2256 * is weird, but possible, so only screw with path if we didn't
2257 * find the key and see if we have stuff that matches
2261 if (path->slots[0] == 0)
2266 /* pull out the item */
2267 leaf = path->nodes[0];
2268 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2270 /* make sure the item matches what we want */
2271 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
2273 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
2276 /* release the path since we're done with it */
2277 btrfs_release_path(path);
2280 * this is where we are basically btrfs_lookup, without the
2281 * crossing root thing. we store the inode number in the
2282 * offset of the orphan item.
2284 found_key.objectid = found_key.offset;
2285 found_key.type = BTRFS_INODE_ITEM_KEY;
2286 found_key.offset = 0;
2287 inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL);
2288 if (IS_ERR(inode)) {
2289 ret = PTR_ERR(inode);
2294 * add this inode to the orphan list so btrfs_orphan_del does
2295 * the proper thing when we hit it
2297 spin_lock(&root->orphan_lock);
2298 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
2299 spin_unlock(&root->orphan_lock);
2302 * if this is a bad inode, means we actually succeeded in
2303 * removing the inode, but not the orphan record, which means
2304 * we need to manually delete the orphan since iput will just
2305 * do a destroy_inode
2307 if (is_bad_inode(inode)) {
2308 trans = btrfs_start_transaction(root, 0);
2309 if (IS_ERR(trans)) {
2310 ret = PTR_ERR(trans);
2313 btrfs_orphan_del(trans, inode);
2314 btrfs_end_transaction(trans, root);
2319 /* if we have links, this was a truncate, lets do that */
2320 if (inode->i_nlink) {
2321 if (!S_ISREG(inode->i_mode)) {
2327 ret = btrfs_truncate(inode);
2332 /* this will do delete_inode and everything for us */
2337 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
2339 if (root->orphan_block_rsv)
2340 btrfs_block_rsv_release(root, root->orphan_block_rsv,
2343 if (root->orphan_block_rsv || root->orphan_item_inserted) {
2344 trans = btrfs_join_transaction(root);
2346 btrfs_end_transaction(trans, root);
2350 printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink);
2352 printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate);
2356 printk(KERN_CRIT "btrfs: could not do orphan cleanup %d\n", ret);
2357 btrfs_free_path(path);
2362 * very simple check to peek ahead in the leaf looking for xattrs. If we
2363 * don't find any xattrs, we know there can't be any acls.
2365 * slot is the slot the inode is in, objectid is the objectid of the inode
2367 static noinline int acls_after_inode_item(struct extent_buffer *leaf,
2368 int slot, u64 objectid)
2370 u32 nritems = btrfs_header_nritems(leaf);
2371 struct btrfs_key found_key;
2375 while (slot < nritems) {
2376 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2378 /* we found a different objectid, there must not be acls */
2379 if (found_key.objectid != objectid)
2382 /* we found an xattr, assume we've got an acl */
2383 if (found_key.type == BTRFS_XATTR_ITEM_KEY)
2387 * we found a key greater than an xattr key, there can't
2388 * be any acls later on
2390 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
2397 * it goes inode, inode backrefs, xattrs, extents,
2398 * so if there are a ton of hard links to an inode there can
2399 * be a lot of backrefs. Don't waste time searching too hard,
2400 * this is just an optimization
2405 /* we hit the end of the leaf before we found an xattr or
2406 * something larger than an xattr. We have to assume the inode
2413 * read an inode from the btree into the in-memory inode
2415 static void btrfs_read_locked_inode(struct inode *inode)
2417 struct btrfs_path *path;
2418 struct extent_buffer *leaf;
2419 struct btrfs_inode_item *inode_item;
2420 struct btrfs_timespec *tspec;
2421 struct btrfs_root *root = BTRFS_I(inode)->root;
2422 struct btrfs_key location;
2426 bool filled = false;
2428 ret = btrfs_fill_inode(inode, &rdev);
2432 path = btrfs_alloc_path();
2436 path->leave_spinning = 1;
2437 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
2439 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
2443 leaf = path->nodes[0];
2448 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2449 struct btrfs_inode_item);
2450 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
2451 inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
2452 inode->i_uid = btrfs_inode_uid(leaf, inode_item);
2453 inode->i_gid = btrfs_inode_gid(leaf, inode_item);
2454 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
2456 tspec = btrfs_inode_atime(inode_item);
2457 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2458 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2460 tspec = btrfs_inode_mtime(inode_item);
2461 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2462 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2464 tspec = btrfs_inode_ctime(inode_item);
2465 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2466 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2468 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
2469 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
2470 BTRFS_I(inode)->sequence = btrfs_inode_sequence(leaf, inode_item);
2471 inode->i_generation = BTRFS_I(inode)->generation;
2473 rdev = btrfs_inode_rdev(leaf, inode_item);
2475 BTRFS_I(inode)->index_cnt = (u64)-1;
2476 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
2479 * try to precache a NULL acl entry for files that don't have
2480 * any xattrs or acls
2482 maybe_acls = acls_after_inode_item(leaf, path->slots[0],
2485 cache_no_acl(inode);
2487 btrfs_free_path(path);
2489 switch (inode->i_mode & S_IFMT) {
2491 inode->i_mapping->a_ops = &btrfs_aops;
2492 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2493 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
2494 inode->i_fop = &btrfs_file_operations;
2495 inode->i_op = &btrfs_file_inode_operations;
2498 inode->i_fop = &btrfs_dir_file_operations;
2499 if (root == root->fs_info->tree_root)
2500 inode->i_op = &btrfs_dir_ro_inode_operations;
2502 inode->i_op = &btrfs_dir_inode_operations;
2505 inode->i_op = &btrfs_symlink_inode_operations;
2506 inode->i_mapping->a_ops = &btrfs_symlink_aops;
2507 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2510 inode->i_op = &btrfs_special_inode_operations;
2511 init_special_inode(inode, inode->i_mode, rdev);
2515 btrfs_update_iflags(inode);
2519 btrfs_free_path(path);
2520 make_bad_inode(inode);
2524 * given a leaf and an inode, copy the inode fields into the leaf
2526 static void fill_inode_item(struct btrfs_trans_handle *trans,
2527 struct extent_buffer *leaf,
2528 struct btrfs_inode_item *item,
2529 struct inode *inode)
2531 btrfs_set_inode_uid(leaf, item, inode->i_uid);
2532 btrfs_set_inode_gid(leaf, item, inode->i_gid);
2533 btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size);
2534 btrfs_set_inode_mode(leaf, item, inode->i_mode);
2535 btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
2537 btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
2538 inode->i_atime.tv_sec);
2539 btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
2540 inode->i_atime.tv_nsec);
2542 btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
2543 inode->i_mtime.tv_sec);
2544 btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
2545 inode->i_mtime.tv_nsec);
2547 btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
2548 inode->i_ctime.tv_sec);
2549 btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
2550 inode->i_ctime.tv_nsec);
2552 btrfs_set_inode_nbytes(leaf, item, inode_get_bytes(inode));
2553 btrfs_set_inode_generation(leaf, item, BTRFS_I(inode)->generation);
2554 btrfs_set_inode_sequence(leaf, item, BTRFS_I(inode)->sequence);
2555 btrfs_set_inode_transid(leaf, item, trans->transid);
2556 btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
2557 btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
2558 btrfs_set_inode_block_group(leaf, item, 0);
2562 * copy everything in the in-memory inode into the btree.
2564 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
2565 struct btrfs_root *root, struct inode *inode)
2567 struct btrfs_inode_item *inode_item;
2568 struct btrfs_path *path;
2569 struct extent_buffer *leaf;
2573 * If the inode is a free space inode, we can deadlock during commit
2574 * if we put it into the delayed code.
2576 * The data relocation inode should also be directly updated
2579 if (!btrfs_is_free_space_inode(root, inode)
2580 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID) {
2581 ret = btrfs_delayed_update_inode(trans, root, inode);
2583 btrfs_set_inode_last_trans(trans, inode);
2587 path = btrfs_alloc_path();
2591 path->leave_spinning = 1;
2592 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location,
2600 btrfs_unlock_up_safe(path, 1);
2601 leaf = path->nodes[0];
2602 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2603 struct btrfs_inode_item);
2605 fill_inode_item(trans, leaf, inode_item, inode);
2606 btrfs_mark_buffer_dirty(leaf);
2607 btrfs_set_inode_last_trans(trans, inode);
2610 btrfs_free_path(path);
2615 * unlink helper that gets used here in inode.c and in the tree logging
2616 * recovery code. It remove a link in a directory with a given name, and
2617 * also drops the back refs in the inode to the directory
2619 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
2620 struct btrfs_root *root,
2621 struct inode *dir, struct inode *inode,
2622 const char *name, int name_len)
2624 struct btrfs_path *path;
2626 struct extent_buffer *leaf;
2627 struct btrfs_dir_item *di;
2628 struct btrfs_key key;
2630 u64 ino = btrfs_ino(inode);
2631 u64 dir_ino = btrfs_ino(dir);
2633 path = btrfs_alloc_path();
2639 path->leave_spinning = 1;
2640 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
2641 name, name_len, -1);
2650 leaf = path->nodes[0];
2651 btrfs_dir_item_key_to_cpu(leaf, di, &key);
2652 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2655 btrfs_release_path(path);
2657 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino,
2660 printk(KERN_INFO "btrfs failed to delete reference to %.*s, "
2661 "inode %llu parent %llu\n", name_len, name,
2662 (unsigned long long)ino, (unsigned long long)dir_ino);
2666 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
2670 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
2672 BUG_ON(ret != 0 && ret != -ENOENT);
2674 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
2679 btrfs_free_path(path);
2683 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
2684 inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
2685 btrfs_update_inode(trans, root, dir);
2690 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
2691 struct btrfs_root *root,
2692 struct inode *dir, struct inode *inode,
2693 const char *name, int name_len)
2696 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
2698 btrfs_drop_nlink(inode);
2699 ret = btrfs_update_inode(trans, root, inode);
2705 /* helper to check if there is any shared block in the path */
2706 static int check_path_shared(struct btrfs_root *root,
2707 struct btrfs_path *path)
2709 struct extent_buffer *eb;
2713 for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
2716 if (!path->nodes[level])
2718 eb = path->nodes[level];
2719 if (!btrfs_block_can_be_shared(root, eb))
2721 ret = btrfs_lookup_extent_info(NULL, root, eb->start, eb->len,
2730 * helper to start transaction for unlink and rmdir.
2732 * unlink and rmdir are special in btrfs, they do not always free space.
2733 * so in enospc case, we should make sure they will free space before
2734 * allowing them to use the global metadata reservation.
2736 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir,
2737 struct dentry *dentry)
2739 struct btrfs_trans_handle *trans;
2740 struct btrfs_root *root = BTRFS_I(dir)->root;
2741 struct btrfs_path *path;
2742 struct btrfs_inode_ref *ref;
2743 struct btrfs_dir_item *di;
2744 struct inode *inode = dentry->d_inode;
2749 u64 ino = btrfs_ino(inode);
2750 u64 dir_ino = btrfs_ino(dir);
2752 trans = btrfs_start_transaction(root, 10);
2753 if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
2756 if (ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
2757 return ERR_PTR(-ENOSPC);
2759 /* check if there is someone else holds reference */
2760 if (S_ISDIR(inode->i_mode) && atomic_read(&inode->i_count) > 1)
2761 return ERR_PTR(-ENOSPC);
2763 if (atomic_read(&inode->i_count) > 2)
2764 return ERR_PTR(-ENOSPC);
2766 if (xchg(&root->fs_info->enospc_unlink, 1))
2767 return ERR_PTR(-ENOSPC);
2769 path = btrfs_alloc_path();
2771 root->fs_info->enospc_unlink = 0;
2772 return ERR_PTR(-ENOMEM);
2775 trans = btrfs_start_transaction(root, 0);
2776 if (IS_ERR(trans)) {
2777 btrfs_free_path(path);
2778 root->fs_info->enospc_unlink = 0;
2782 path->skip_locking = 1;
2783 path->search_commit_root = 1;
2785 ret = btrfs_lookup_inode(trans, root, path,
2786 &BTRFS_I(dir)->location, 0);
2792 if (check_path_shared(root, path))
2797 btrfs_release_path(path);
2799 ret = btrfs_lookup_inode(trans, root, path,
2800 &BTRFS_I(inode)->location, 0);
2806 if (check_path_shared(root, path))
2811 btrfs_release_path(path);
2813 if (ret == 0 && S_ISREG(inode->i_mode)) {
2814 ret = btrfs_lookup_file_extent(trans, root, path,
2821 if (check_path_shared(root, path))
2823 btrfs_release_path(path);
2831 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
2832 dentry->d_name.name, dentry->d_name.len, 0);
2838 if (check_path_shared(root, path))
2844 btrfs_release_path(path);
2846 ref = btrfs_lookup_inode_ref(trans, root, path,
2847 dentry->d_name.name, dentry->d_name.len,
2854 if (check_path_shared(root, path))
2856 index = btrfs_inode_ref_index(path->nodes[0], ref);
2857 btrfs_release_path(path);
2860 * This is a commit root search, if we can lookup inode item and other
2861 * relative items in the commit root, it means the transaction of
2862 * dir/file creation has been committed, and the dir index item that we
2863 * delay to insert has also been inserted into the commit root. So
2864 * we needn't worry about the delayed insertion of the dir index item
2867 di = btrfs_lookup_dir_index_item(trans, root, path, dir_ino, index,
2868 dentry->d_name.name, dentry->d_name.len, 0);
2873 BUG_ON(ret == -ENOENT);
2874 if (check_path_shared(root, path))
2879 btrfs_free_path(path);
2881 btrfs_end_transaction(trans, root);
2882 root->fs_info->enospc_unlink = 0;
2883 return ERR_PTR(err);
2886 trans->block_rsv = &root->fs_info->global_block_rsv;
2890 static void __unlink_end_trans(struct btrfs_trans_handle *trans,
2891 struct btrfs_root *root)
2893 if (trans->block_rsv == &root->fs_info->global_block_rsv) {
2894 BUG_ON(!root->fs_info->enospc_unlink);
2895 root->fs_info->enospc_unlink = 0;
2897 btrfs_end_transaction_throttle(trans, root);
2900 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
2902 struct btrfs_root *root = BTRFS_I(dir)->root;
2903 struct btrfs_trans_handle *trans;
2904 struct inode *inode = dentry->d_inode;
2906 unsigned long nr = 0;
2908 trans = __unlink_start_trans(dir, dentry);
2910 return PTR_ERR(trans);
2912 btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0);
2914 ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
2915 dentry->d_name.name, dentry->d_name.len);
2919 if (inode->i_nlink == 0) {
2920 ret = btrfs_orphan_add(trans, inode);
2926 nr = trans->blocks_used;
2927 __unlink_end_trans(trans, root);
2928 btrfs_btree_balance_dirty(root, nr);
2932 int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
2933 struct btrfs_root *root,
2934 struct inode *dir, u64 objectid,
2935 const char *name, int name_len)
2937 struct btrfs_path *path;
2938 struct extent_buffer *leaf;
2939 struct btrfs_dir_item *di;
2940 struct btrfs_key key;
2943 u64 dir_ino = btrfs_ino(dir);
2945 path = btrfs_alloc_path();
2949 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
2950 name, name_len, -1);
2951 BUG_ON(IS_ERR_OR_NULL(di));
2953 leaf = path->nodes[0];
2954 btrfs_dir_item_key_to_cpu(leaf, di, &key);
2955 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
2956 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2958 btrfs_release_path(path);
2960 ret = btrfs_del_root_ref(trans, root->fs_info->tree_root,
2961 objectid, root->root_key.objectid,
2962 dir_ino, &index, name, name_len);
2964 BUG_ON(ret != -ENOENT);
2965 di = btrfs_search_dir_index_item(root, path, dir_ino,
2967 BUG_ON(IS_ERR_OR_NULL(di));
2969 leaf = path->nodes[0];
2970 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2971 btrfs_release_path(path);
2974 btrfs_release_path(path);
2976 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
2979 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
2980 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
2981 ret = btrfs_update_inode(trans, root, dir);
2984 btrfs_free_path(path);
2988 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
2990 struct inode *inode = dentry->d_inode;
2992 struct btrfs_root *root = BTRFS_I(dir)->root;
2993 struct btrfs_trans_handle *trans;
2994 unsigned long nr = 0;
2996 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE ||
2997 btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID)
3000 trans = __unlink_start_trans(dir, dentry);
3002 return PTR_ERR(trans);
3004 if (unlikely(btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
3005 err = btrfs_unlink_subvol(trans, root, dir,
3006 BTRFS_I(inode)->location.objectid,
3007 dentry->d_name.name,
3008 dentry->d_name.len);
3012 err = btrfs_orphan_add(trans, inode);
3016 /* now the directory is empty */
3017 err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
3018 dentry->d_name.name, dentry->d_name.len);
3020 btrfs_i_size_write(inode, 0);
3022 nr = trans->blocks_used;
3023 __unlink_end_trans(trans, root);
3024 btrfs_btree_balance_dirty(root, nr);
3030 * this can truncate away extent items, csum items and directory items.
3031 * It starts at a high offset and removes keys until it can't find
3032 * any higher than new_size
3034 * csum items that cross the new i_size are truncated to the new size
3037 * min_type is the minimum key type to truncate down to. If set to 0, this
3038 * will kill all the items on this inode, including the INODE_ITEM_KEY.
3040 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
3041 struct btrfs_root *root,
3042 struct inode *inode,
3043 u64 new_size, u32 min_type)
3045 struct btrfs_path *path;
3046 struct extent_buffer *leaf;
3047 struct btrfs_file_extent_item *fi;
3048 struct btrfs_key key;
3049 struct btrfs_key found_key;
3050 u64 extent_start = 0;
3051 u64 extent_num_bytes = 0;
3052 u64 extent_offset = 0;
3054 u64 mask = root->sectorsize - 1;
3055 u32 found_type = (u8)-1;
3058 int pending_del_nr = 0;
3059 int pending_del_slot = 0;
3060 int extent_type = -1;
3064 u64 ino = btrfs_ino(inode);
3066 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
3068 path = btrfs_alloc_path();
3073 if (root->ref_cows || root == root->fs_info->tree_root)
3074 btrfs_drop_extent_cache(inode, new_size & (~mask), (u64)-1, 0);
3077 * This function is also used to drop the items in the log tree before
3078 * we relog the inode, so if root != BTRFS_I(inode)->root, it means
3079 * it is used to drop the loged items. So we shouldn't kill the delayed
3082 if (min_type == 0 && root == BTRFS_I(inode)->root)
3083 btrfs_kill_delayed_inode_items(inode);
3086 key.offset = (u64)-1;
3090 path->leave_spinning = 1;
3091 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3098 /* there are no items in the tree for us to truncate, we're
3101 if (path->slots[0] == 0)
3108 leaf = path->nodes[0];
3109 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3110 found_type = btrfs_key_type(&found_key);
3113 if (found_key.objectid != ino)
3116 if (found_type < min_type)
3119 item_end = found_key.offset;
3120 if (found_type == BTRFS_EXTENT_DATA_KEY) {
3121 fi = btrfs_item_ptr(leaf, path->slots[0],
3122 struct btrfs_file_extent_item);
3123 extent_type = btrfs_file_extent_type(leaf, fi);
3124 encoding = btrfs_file_extent_compression(leaf, fi);
3125 encoding |= btrfs_file_extent_encryption(leaf, fi);
3126 encoding |= btrfs_file_extent_other_encoding(leaf, fi);
3128 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
3130 btrfs_file_extent_num_bytes(leaf, fi);
3131 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
3132 item_end += btrfs_file_extent_inline_len(leaf,
3137 if (found_type > min_type) {
3140 if (item_end < new_size)
3142 if (found_key.offset >= new_size)
3148 /* FIXME, shrink the extent if the ref count is only 1 */
3149 if (found_type != BTRFS_EXTENT_DATA_KEY)
3152 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
3154 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
3155 if (!del_item && !encoding) {
3156 u64 orig_num_bytes =
3157 btrfs_file_extent_num_bytes(leaf, fi);
3158 extent_num_bytes = new_size -
3159 found_key.offset + root->sectorsize - 1;
3160 extent_num_bytes = extent_num_bytes &
3161 ~((u64)root->sectorsize - 1);
3162 btrfs_set_file_extent_num_bytes(leaf, fi,
3164 num_dec = (orig_num_bytes -
3166 if (root->ref_cows && extent_start != 0)
3167 inode_sub_bytes(inode, num_dec);
3168 btrfs_mark_buffer_dirty(leaf);
3171 btrfs_file_extent_disk_num_bytes(leaf,
3173 extent_offset = found_key.offset -
3174 btrfs_file_extent_offset(leaf, fi);
3176 /* FIXME blocksize != 4096 */
3177 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
3178 if (extent_start != 0) {
3181 inode_sub_bytes(inode, num_dec);
3184 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
3186 * we can't truncate inline items that have had
3190 btrfs_file_extent_compression(leaf, fi) == 0 &&
3191 btrfs_file_extent_encryption(leaf, fi) == 0 &&
3192 btrfs_file_extent_other_encoding(leaf, fi) == 0) {
3193 u32 size = new_size - found_key.offset;
3195 if (root->ref_cows) {
3196 inode_sub_bytes(inode, item_end + 1 -
3200 btrfs_file_extent_calc_inline_size(size);
3201 ret = btrfs_truncate_item(trans, root, path,
3203 } else if (root->ref_cows) {
3204 inode_sub_bytes(inode, item_end + 1 -
3210 if (!pending_del_nr) {
3211 /* no pending yet, add ourselves */
3212 pending_del_slot = path->slots[0];
3214 } else if (pending_del_nr &&
3215 path->slots[0] + 1 == pending_del_slot) {
3216 /* hop on the pending chunk */
3218 pending_del_slot = path->slots[0];
3225 if (found_extent && (root->ref_cows ||
3226 root == root->fs_info->tree_root)) {
3227 btrfs_set_path_blocking(path);
3228 ret = btrfs_free_extent(trans, root, extent_start,
3229 extent_num_bytes, 0,
3230 btrfs_header_owner(leaf),
3231 ino, extent_offset);
3235 if (found_type == BTRFS_INODE_ITEM_KEY)
3238 if (path->slots[0] == 0 ||
3239 path->slots[0] != pending_del_slot) {
3240 if (root->ref_cows &&
3241 BTRFS_I(inode)->location.objectid !=
3242 BTRFS_FREE_INO_OBJECTID) {
3246 if (pending_del_nr) {
3247 ret = btrfs_del_items(trans, root, path,
3253 btrfs_release_path(path);
3260 if (pending_del_nr) {
3261 ret = btrfs_del_items(trans, root, path, pending_del_slot,
3265 btrfs_free_path(path);
3270 * taken from block_truncate_page, but does cow as it zeros out
3271 * any bytes left in the last page in the file.
3273 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
3275 struct inode *inode = mapping->host;
3276 struct btrfs_root *root = BTRFS_I(inode)->root;
3277 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3278 struct btrfs_ordered_extent *ordered;
3279 struct extent_state *cached_state = NULL;
3281 u32 blocksize = root->sectorsize;
3282 pgoff_t index = from >> PAGE_CACHE_SHIFT;
3283 unsigned offset = from & (PAGE_CACHE_SIZE-1);
3289 if ((offset & (blocksize - 1)) == 0)
3291 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
3297 page = find_or_create_page(mapping, index, GFP_NOFS);
3299 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
3303 page_start = page_offset(page);
3304 page_end = page_start + PAGE_CACHE_SIZE - 1;
3306 if (!PageUptodate(page)) {
3307 ret = btrfs_readpage(NULL, page);
3309 if (page->mapping != mapping) {
3311 page_cache_release(page);
3314 if (!PageUptodate(page)) {
3319 wait_on_page_writeback(page);
3321 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state,
3323 set_page_extent_mapped(page);
3325 ordered = btrfs_lookup_ordered_extent(inode, page_start);
3327 unlock_extent_cached(io_tree, page_start, page_end,
3328 &cached_state, GFP_NOFS);
3330 page_cache_release(page);
3331 btrfs_start_ordered_extent(inode, ordered, 1);
3332 btrfs_put_ordered_extent(ordered);
3336 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
3337 EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
3338 0, 0, &cached_state, GFP_NOFS);
3340 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
3343 unlock_extent_cached(io_tree, page_start, page_end,
3344 &cached_state, GFP_NOFS);
3349 if (offset != PAGE_CACHE_SIZE) {
3351 memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
3352 flush_dcache_page(page);
3355 ClearPageChecked(page);
3356 set_page_dirty(page);
3357 unlock_extent_cached(io_tree, page_start, page_end, &cached_state,
3362 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
3364 page_cache_release(page);
3370 * This function puts in dummy file extents for the area we're creating a hole
3371 * for. So if we are truncating this file to a larger size we need to insert
3372 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
3373 * the range between oldsize and size
3375 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
3377 struct btrfs_trans_handle *trans;
3378 struct btrfs_root *root = BTRFS_I(inode)->root;
3379 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3380 struct extent_map *em = NULL;
3381 struct extent_state *cached_state = NULL;
3382 u64 mask = root->sectorsize - 1;
3383 u64 hole_start = (oldsize + mask) & ~mask;
3384 u64 block_end = (size + mask) & ~mask;
3390 if (size <= hole_start)
3394 struct btrfs_ordered_extent *ordered;
3395 btrfs_wait_ordered_range(inode, hole_start,
3396 block_end - hole_start);
3397 lock_extent_bits(io_tree, hole_start, block_end - 1, 0,
3398 &cached_state, GFP_NOFS);
3399 ordered = btrfs_lookup_ordered_extent(inode, hole_start);
3402 unlock_extent_cached(io_tree, hole_start, block_end - 1,
3403 &cached_state, GFP_NOFS);
3404 btrfs_put_ordered_extent(ordered);
3407 cur_offset = hole_start;
3409 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
3410 block_end - cur_offset, 0);
3411 BUG_ON(IS_ERR_OR_NULL(em));
3412 last_byte = min(extent_map_end(em), block_end);
3413 last_byte = (last_byte + mask) & ~mask;
3414 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
3416 hole_size = last_byte - cur_offset;
3418 trans = btrfs_start_transaction(root, 2);
3419 if (IS_ERR(trans)) {
3420 err = PTR_ERR(trans);
3424 err = btrfs_drop_extents(trans, inode, cur_offset,
3425 cur_offset + hole_size,
3428 btrfs_end_transaction(trans, root);
3432 err = btrfs_insert_file_extent(trans, root,
3433 btrfs_ino(inode), cur_offset, 0,
3434 0, hole_size, 0, hole_size,
3437 btrfs_end_transaction(trans, root);
3441 btrfs_drop_extent_cache(inode, hole_start,
3444 btrfs_end_transaction(trans, root);
3446 free_extent_map(em);
3448 cur_offset = last_byte;
3449 if (cur_offset >= block_end)
3453 free_extent_map(em);
3454 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state,
3459 static int btrfs_setsize(struct inode *inode, loff_t newsize)
3461 loff_t oldsize = i_size_read(inode);
3464 if (newsize == oldsize)
3467 if (newsize > oldsize) {
3468 i_size_write(inode, newsize);
3469 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL);
3470 truncate_pagecache(inode, oldsize, newsize);
3471 ret = btrfs_cont_expand(inode, oldsize, newsize);
3473 btrfs_setsize(inode, oldsize);
3477 mark_inode_dirty(inode);
3481 * We're truncating a file that used to have good data down to
3482 * zero. Make sure it gets into the ordered flush list so that
3483 * any new writes get down to disk quickly.
3486 BTRFS_I(inode)->ordered_data_close = 1;
3488 /* we don't support swapfiles, so vmtruncate shouldn't fail */
3489 truncate_setsize(inode, newsize);
3490 ret = btrfs_truncate(inode);
3496 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
3498 struct inode *inode = dentry->d_inode;
3499 struct btrfs_root *root = BTRFS_I(inode)->root;
3502 if (btrfs_root_readonly(root))
3505 err = inode_change_ok(inode, attr);
3509 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
3510 err = btrfs_setsize(inode, attr->ia_size);
3515 if (attr->ia_valid) {
3516 setattr_copy(inode, attr);
3517 mark_inode_dirty(inode);
3519 if (attr->ia_valid & ATTR_MODE)
3520 err = btrfs_acl_chmod(inode);
3526 void btrfs_evict_inode(struct inode *inode)
3528 struct btrfs_trans_handle *trans;
3529 struct btrfs_root *root = BTRFS_I(inode)->root;
3533 trace_btrfs_inode_evict(inode);
3535 truncate_inode_pages(&inode->i_data, 0);
3536 if (inode->i_nlink && (btrfs_root_refs(&root->root_item) != 0 ||
3537 btrfs_is_free_space_inode(root, inode)))
3540 if (is_bad_inode(inode)) {
3541 btrfs_orphan_del(NULL, inode);
3544 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */
3545 btrfs_wait_ordered_range(inode, 0, (u64)-1);
3547 if (root->fs_info->log_root_recovering) {
3548 BUG_ON(!list_empty(&BTRFS_I(inode)->i_orphan));
3552 if (inode->i_nlink > 0) {
3553 BUG_ON(btrfs_root_refs(&root->root_item) != 0);
3557 btrfs_i_size_write(inode, 0);
3560 trans = btrfs_join_transaction(root);
3561 BUG_ON(IS_ERR(trans));
3562 trans->block_rsv = root->orphan_block_rsv;
3564 ret = btrfs_block_rsv_check(trans, root,
3565 root->orphan_block_rsv, 0, 5);
3567 BUG_ON(ret != -EAGAIN);
3568 ret = btrfs_commit_transaction(trans, root);
3573 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
3577 nr = trans->blocks_used;
3578 btrfs_end_transaction(trans, root);
3580 btrfs_btree_balance_dirty(root, nr);
3585 ret = btrfs_orphan_del(trans, inode);
3589 if (!(root == root->fs_info->tree_root ||
3590 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
3591 btrfs_return_ino(root, btrfs_ino(inode));
3593 nr = trans->blocks_used;
3594 btrfs_end_transaction(trans, root);
3595 btrfs_btree_balance_dirty(root, nr);
3597 end_writeback(inode);
3602 * this returns the key found in the dir entry in the location pointer.
3603 * If no dir entries were found, location->objectid is 0.
3605 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
3606 struct btrfs_key *location)
3608 const char *name = dentry->d_name.name;
3609 int namelen = dentry->d_name.len;
3610 struct btrfs_dir_item *di;
3611 struct btrfs_path *path;
3612 struct btrfs_root *root = BTRFS_I(dir)->root;
3615 path = btrfs_alloc_path();
3619 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir), name,
3624 if (IS_ERR_OR_NULL(di))
3627 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
3629 btrfs_free_path(path);
3632 location->objectid = 0;
3637 * when we hit a tree root in a directory, the btrfs part of the inode
3638 * needs to be changed to reflect the root directory of the tree root. This
3639 * is kind of like crossing a mount point.
3641 static int fixup_tree_root_location(struct btrfs_root *root,
3643 struct dentry *dentry,
3644 struct btrfs_key *location,
3645 struct btrfs_root **sub_root)
3647 struct btrfs_path *path;
3648 struct btrfs_root *new_root;
3649 struct btrfs_root_ref *ref;
3650 struct extent_buffer *leaf;
3654 path = btrfs_alloc_path();
3661 ret = btrfs_find_root_ref(root->fs_info->tree_root, path,
3662 BTRFS_I(dir)->root->root_key.objectid,
3663 location->objectid);
3670 leaf = path->nodes[0];
3671 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
3672 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(dir) ||
3673 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
3676 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
3677 (unsigned long)(ref + 1),
3678 dentry->d_name.len);
3682 btrfs_release_path(path);
3684 new_root = btrfs_read_fs_root_no_name(root->fs_info, location);
3685 if (IS_ERR(new_root)) {
3686 err = PTR_ERR(new_root);
3690 if (btrfs_root_refs(&new_root->root_item) == 0) {
3695 *sub_root = new_root;
3696 location->objectid = btrfs_root_dirid(&new_root->root_item);
3697 location->type = BTRFS_INODE_ITEM_KEY;
3698 location->offset = 0;
3701 btrfs_free_path(path);
3705 static void inode_tree_add(struct inode *inode)
3707 struct btrfs_root *root = BTRFS_I(inode)->root;
3708 struct btrfs_inode *entry;
3710 struct rb_node *parent;
3711 u64 ino = btrfs_ino(inode);
3713 p = &root->inode_tree.rb_node;
3716 if (inode_unhashed(inode))
3719 spin_lock(&root->inode_lock);
3722 entry = rb_entry(parent, struct btrfs_inode, rb_node);
3724 if (ino < btrfs_ino(&entry->vfs_inode))
3725 p = &parent->rb_left;
3726 else if (ino > btrfs_ino(&entry->vfs_inode))
3727 p = &parent->rb_right;
3729 WARN_ON(!(entry->vfs_inode.i_state &
3730 (I_WILL_FREE | I_FREEING)));
3731 rb_erase(parent, &root->inode_tree);
3732 RB_CLEAR_NODE(parent);
3733 spin_unlock(&root->inode_lock);
3737 rb_link_node(&BTRFS_I(inode)->rb_node, parent, p);
3738 rb_insert_color(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3739 spin_unlock(&root->inode_lock);
3742 static void inode_tree_del(struct inode *inode)
3744 struct btrfs_root *root = BTRFS_I(inode)->root;
3747 spin_lock(&root->inode_lock);
3748 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
3749 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3750 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
3751 empty = RB_EMPTY_ROOT(&root->inode_tree);
3753 spin_unlock(&root->inode_lock);
3756 * Free space cache has inodes in the tree root, but the tree root has a
3757 * root_refs of 0, so this could end up dropping the tree root as a
3758 * snapshot, so we need the extra !root->fs_info->tree_root check to
3759 * make sure we don't drop it.
3761 if (empty && btrfs_root_refs(&root->root_item) == 0 &&
3762 root != root->fs_info->tree_root) {
3763 synchronize_srcu(&root->fs_info->subvol_srcu);
3764 spin_lock(&root->inode_lock);
3765 empty = RB_EMPTY_ROOT(&root->inode_tree);
3766 spin_unlock(&root->inode_lock);
3768 btrfs_add_dead_root(root);
3772 int btrfs_invalidate_inodes(struct btrfs_root *root)
3774 struct rb_node *node;
3775 struct rb_node *prev;
3776 struct btrfs_inode *entry;
3777 struct inode *inode;
3780 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
3782 spin_lock(&root->inode_lock);
3784 node = root->inode_tree.rb_node;
3788 entry = rb_entry(node, struct btrfs_inode, rb_node);
3790 if (objectid < btrfs_ino(&entry->vfs_inode))
3791 node = node->rb_left;
3792 else if (objectid > btrfs_ino(&entry->vfs_inode))
3793 node = node->rb_right;
3799 entry = rb_entry(prev, struct btrfs_inode, rb_node);
3800 if (objectid <= btrfs_ino(&entry->vfs_inode)) {
3804 prev = rb_next(prev);
3808 entry = rb_entry(node, struct btrfs_inode, rb_node);
3809 objectid = btrfs_ino(&entry->vfs_inode) + 1;
3810 inode = igrab(&entry->vfs_inode);
3812 spin_unlock(&root->inode_lock);
3813 if (atomic_read(&inode->i_count) > 1)
3814 d_prune_aliases(inode);
3816 * btrfs_drop_inode will have it removed from
3817 * the inode cache when its usage count
3822 spin_lock(&root->inode_lock);
3826 if (cond_resched_lock(&root->inode_lock))
3829 node = rb_next(node);
3831 spin_unlock(&root->inode_lock);
3835 static int btrfs_init_locked_inode(struct inode *inode, void *p)
3837 struct btrfs_iget_args *args = p;
3838 inode->i_ino = args->ino;
3839 BTRFS_I(inode)->root = args->root;
3840 btrfs_set_inode_space_info(args->root, inode);
3844 static int btrfs_find_actor(struct inode *inode, void *opaque)
3846 struct btrfs_iget_args *args = opaque;
3847 return args->ino == btrfs_ino(inode) &&
3848 args->root == BTRFS_I(inode)->root;
3851 static struct inode *btrfs_iget_locked(struct super_block *s,
3853 struct btrfs_root *root)
3855 struct inode *inode;
3856 struct btrfs_iget_args args;
3857 args.ino = objectid;
3860 inode = iget5_locked(s, objectid, btrfs_find_actor,
3861 btrfs_init_locked_inode,
3866 /* Get an inode object given its location and corresponding root.
3867 * Returns in *is_new if the inode was read from disk
3869 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
3870 struct btrfs_root *root, int *new)
3872 struct inode *inode;
3874 inode = btrfs_iget_locked(s, location->objectid, root);
3876 return ERR_PTR(-ENOMEM);
3878 if (inode->i_state & I_NEW) {
3879 BTRFS_I(inode)->root = root;
3880 memcpy(&BTRFS_I(inode)->location, location, sizeof(*location));
3881 btrfs_read_locked_inode(inode);
3882 if (!is_bad_inode(inode)) {
3883 inode_tree_add(inode);
3884 unlock_new_inode(inode);
3888 unlock_new_inode(inode);
3890 inode = ERR_PTR(-ESTALE);
3897 static struct inode *new_simple_dir(struct super_block *s,
3898 struct btrfs_key *key,
3899 struct btrfs_root *root)
3901 struct inode *inode = new_inode(s);
3904 return ERR_PTR(-ENOMEM);
3906 BTRFS_I(inode)->root = root;
3907 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
3908 BTRFS_I(inode)->dummy_inode = 1;
3910 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
3911 inode->i_op = &simple_dir_inode_operations;
3912 inode->i_fop = &simple_dir_operations;
3913 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
3914 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
3919 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
3921 struct inode *inode;
3922 struct btrfs_root *root = BTRFS_I(dir)->root;
3923 struct btrfs_root *sub_root = root;
3924 struct btrfs_key location;
3928 if (dentry->d_name.len > BTRFS_NAME_LEN)
3929 return ERR_PTR(-ENAMETOOLONG);
3931 if (unlikely(d_need_lookup(dentry))) {
3932 memcpy(&location, dentry->d_fsdata, sizeof(struct btrfs_key));
3933 kfree(dentry->d_fsdata);
3934 dentry->d_fsdata = NULL;
3935 /* This thing is hashed, drop it for now */
3938 ret = btrfs_inode_by_name(dir, dentry, &location);
3942 return ERR_PTR(ret);
3944 if (location.objectid == 0)
3947 if (location.type == BTRFS_INODE_ITEM_KEY) {
3948 inode = btrfs_iget(dir->i_sb, &location, root, NULL);
3952 BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY);
3954 index = srcu_read_lock(&root->fs_info->subvol_srcu);
3955 ret = fixup_tree_root_location(root, dir, dentry,
3956 &location, &sub_root);
3959 inode = ERR_PTR(ret);
3961 inode = new_simple_dir(dir->i_sb, &location, sub_root);
3963 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL);
3965 srcu_read_unlock(&root->fs_info->subvol_srcu, index);
3967 if (!IS_ERR(inode) && root != sub_root) {
3968 down_read(&root->fs_info->cleanup_work_sem);
3969 if (!(inode->i_sb->s_flags & MS_RDONLY))
3970 ret = btrfs_orphan_cleanup(sub_root);
3971 up_read(&root->fs_info->cleanup_work_sem);
3973 inode = ERR_PTR(ret);
3979 static int btrfs_dentry_delete(const struct dentry *dentry)
3981 struct btrfs_root *root;
3983 if (!dentry->d_inode && !IS_ROOT(dentry))
3984 dentry = dentry->d_parent;
3986 if (dentry->d_inode) {
3987 root = BTRFS_I(dentry->d_inode)->root;
3988 if (btrfs_root_refs(&root->root_item) == 0)
3994 static void btrfs_dentry_release(struct dentry *dentry)
3996 if (dentry->d_fsdata)
3997 kfree(dentry->d_fsdata);
4000 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
4001 struct nameidata *nd)
4005 ret = d_splice_alias(btrfs_lookup_dentry(dir, dentry), dentry);
4006 if (unlikely(d_need_lookup(dentry))) {
4007 spin_lock(&dentry->d_lock);
4008 dentry->d_flags &= ~DCACHE_NEED_LOOKUP;
4009 spin_unlock(&dentry->d_lock);
4014 unsigned char btrfs_filetype_table[] = {
4015 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
4018 static int btrfs_real_readdir(struct file *filp, void *dirent,
4021 struct inode *inode = filp->f_dentry->d_inode;
4022 struct btrfs_root *root = BTRFS_I(inode)->root;
4023 struct btrfs_item *item;
4024 struct btrfs_dir_item *di;
4025 struct btrfs_key key;
4026 struct btrfs_key found_key;
4027 struct btrfs_path *path;
4028 struct list_head ins_list;
4029 struct list_head del_list;
4032 struct extent_buffer *leaf;
4034 unsigned char d_type;
4039 int key_type = BTRFS_DIR_INDEX_KEY;
4043 int is_curr = 0; /* filp->f_pos points to the current index? */
4045 /* FIXME, use a real flag for deciding about the key type */
4046 if (root->fs_info->tree_root == root)
4047 key_type = BTRFS_DIR_ITEM_KEY;
4049 /* special case for "." */
4050 if (filp->f_pos == 0) {
4051 over = filldir(dirent, ".", 1,
4052 filp->f_pos, btrfs_ino(inode), DT_DIR);
4057 /* special case for .., just use the back ref */
4058 if (filp->f_pos == 1) {
4059 u64 pino = parent_ino(filp->f_path.dentry);
4060 over = filldir(dirent, "..", 2,
4061 filp->f_pos, pino, DT_DIR);
4066 path = btrfs_alloc_path();
4072 if (key_type == BTRFS_DIR_INDEX_KEY) {
4073 INIT_LIST_HEAD(&ins_list);
4074 INIT_LIST_HEAD(&del_list);
4075 btrfs_get_delayed_items(inode, &ins_list, &del_list);
4078 btrfs_set_key_type(&key, key_type);
4079 key.offset = filp->f_pos;
4080 key.objectid = btrfs_ino(inode);
4082 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4087 leaf = path->nodes[0];
4088 slot = path->slots[0];
4089 if (slot >= btrfs_header_nritems(leaf)) {
4090 ret = btrfs_next_leaf(root, path);
4098 item = btrfs_item_nr(leaf, slot);
4099 btrfs_item_key_to_cpu(leaf, &found_key, slot);
4101 if (found_key.objectid != key.objectid)
4103 if (btrfs_key_type(&found_key) != key_type)
4105 if (found_key.offset < filp->f_pos)
4107 if (key_type == BTRFS_DIR_INDEX_KEY &&
4108 btrfs_should_delete_dir_index(&del_list,
4112 filp->f_pos = found_key.offset;
4115 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
4117 di_total = btrfs_item_size(leaf, item);
4119 while (di_cur < di_total) {
4120 struct btrfs_key location;
4123 if (verify_dir_item(root, leaf, di))
4126 name_len = btrfs_dir_name_len(leaf, di);
4127 if (name_len <= sizeof(tmp_name)) {
4128 name_ptr = tmp_name;
4130 name_ptr = kmalloc(name_len, GFP_NOFS);
4136 read_extent_buffer(leaf, name_ptr,
4137 (unsigned long)(di + 1), name_len);
4139 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
4140 btrfs_dir_item_key_to_cpu(leaf, di, &location);
4144 q.hash = full_name_hash(q.name, q.len);
4145 tmp = d_lookup(filp->f_dentry, &q);
4147 struct btrfs_key *newkey;
4149 newkey = kzalloc(sizeof(struct btrfs_key),
4153 tmp = d_alloc(filp->f_dentry, &q);
4159 memcpy(newkey, &location,
4160 sizeof(struct btrfs_key));
4161 tmp->d_fsdata = newkey;
4162 tmp->d_flags |= DCACHE_NEED_LOOKUP;
4169 /* is this a reference to our own snapshot? If so
4172 if (location.type == BTRFS_ROOT_ITEM_KEY &&
4173 location.objectid == root->root_key.objectid) {
4177 over = filldir(dirent, name_ptr, name_len,
4178 found_key.offset, location.objectid,
4182 if (name_ptr != tmp_name)
4187 di_len = btrfs_dir_name_len(leaf, di) +
4188 btrfs_dir_data_len(leaf, di) + sizeof(*di);
4190 di = (struct btrfs_dir_item *)((char *)di + di_len);
4196 if (key_type == BTRFS_DIR_INDEX_KEY) {
4199 ret = btrfs_readdir_delayed_dir_index(filp, dirent, filldir,
4205 /* Reached end of directory/root. Bump pos past the last item. */
4206 if (key_type == BTRFS_DIR_INDEX_KEY)
4208 * 32-bit glibc will use getdents64, but then strtol -
4209 * so the last number we can serve is this.
4211 filp->f_pos = 0x7fffffff;
4217 if (key_type == BTRFS_DIR_INDEX_KEY)
4218 btrfs_put_delayed_items(&ins_list, &del_list);
4219 btrfs_free_path(path);
4223 int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc)
4225 struct btrfs_root *root = BTRFS_I(inode)->root;
4226 struct btrfs_trans_handle *trans;
4228 bool nolock = false;
4230 if (BTRFS_I(inode)->dummy_inode)
4233 if (btrfs_fs_closing(root->fs_info) && btrfs_is_free_space_inode(root, inode))
4236 if (wbc->sync_mode == WB_SYNC_ALL) {
4238 trans = btrfs_join_transaction_nolock(root);
4240 trans = btrfs_join_transaction(root);
4242 return PTR_ERR(trans);
4244 ret = btrfs_end_transaction_nolock(trans, root);
4246 ret = btrfs_commit_transaction(trans, root);
4252 * This is somewhat expensive, updating the tree every time the
4253 * inode changes. But, it is most likely to find the inode in cache.
4254 * FIXME, needs more benchmarking...there are no reasons other than performance
4255 * to keep or drop this code.
4257 void btrfs_dirty_inode(struct inode *inode, int flags)
4259 struct btrfs_root *root = BTRFS_I(inode)->root;
4260 struct btrfs_trans_handle *trans;
4263 if (BTRFS_I(inode)->dummy_inode)
4266 trans = btrfs_join_transaction(root);
4267 BUG_ON(IS_ERR(trans));
4269 ret = btrfs_update_inode(trans, root, inode);
4270 if (ret && ret == -ENOSPC) {
4271 /* whoops, lets try again with the full transaction */
4272 btrfs_end_transaction(trans, root);
4273 trans = btrfs_start_transaction(root, 1);
4274 if (IS_ERR(trans)) {
4275 printk_ratelimited(KERN_ERR "btrfs: fail to "
4276 "dirty inode %llu error %ld\n",
4277 (unsigned long long)btrfs_ino(inode),
4282 ret = btrfs_update_inode(trans, root, inode);
4284 printk_ratelimited(KERN_ERR "btrfs: fail to "
4285 "dirty inode %llu error %d\n",
4286 (unsigned long long)btrfs_ino(inode),
4290 btrfs_end_transaction(trans, root);
4291 if (BTRFS_I(inode)->delayed_node)
4292 btrfs_balance_delayed_items(root);
4296 * find the highest existing sequence number in a directory
4297 * and then set the in-memory index_cnt variable to reflect
4298 * free sequence numbers
4300 static int btrfs_set_inode_index_count(struct inode *inode)
4302 struct btrfs_root *root = BTRFS_I(inode)->root;
4303 struct btrfs_key key, found_key;
4304 struct btrfs_path *path;
4305 struct extent_buffer *leaf;
4308 key.objectid = btrfs_ino(inode);
4309 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
4310 key.offset = (u64)-1;
4312 path = btrfs_alloc_path();
4316 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4319 /* FIXME: we should be able to handle this */
4325 * MAGIC NUMBER EXPLANATION:
4326 * since we search a directory based on f_pos we have to start at 2
4327 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
4328 * else has to start at 2
4330 if (path->slots[0] == 0) {
4331 BTRFS_I(inode)->index_cnt = 2;
4337 leaf = path->nodes[0];
4338 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4340 if (found_key.objectid != btrfs_ino(inode) ||
4341 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
4342 BTRFS_I(inode)->index_cnt = 2;
4346 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
4348 btrfs_free_path(path);
4353 * helper to find a free sequence number in a given directory. This current
4354 * code is very simple, later versions will do smarter things in the btree
4356 int btrfs_set_inode_index(struct inode *dir, u64 *index)
4360 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
4361 ret = btrfs_inode_delayed_dir_index_count(dir);
4363 ret = btrfs_set_inode_index_count(dir);
4369 *index = BTRFS_I(dir)->index_cnt;
4370 BTRFS_I(dir)->index_cnt++;
4375 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
4376 struct btrfs_root *root,
4378 const char *name, int name_len,
4379 u64 ref_objectid, u64 objectid, int mode,
4382 struct inode *inode;
4383 struct btrfs_inode_item *inode_item;
4384 struct btrfs_key *location;
4385 struct btrfs_path *path;
4386 struct btrfs_inode_ref *ref;
4387 struct btrfs_key key[2];
4393 path = btrfs_alloc_path();
4395 return ERR_PTR(-ENOMEM);
4397 inode = new_inode(root->fs_info->sb);
4399 btrfs_free_path(path);
4400 return ERR_PTR(-ENOMEM);
4404 * we have to initialize this early, so we can reclaim the inode
4405 * number if we fail afterwards in this function.
4407 inode->i_ino = objectid;
4410 trace_btrfs_inode_request(dir);
4412 ret = btrfs_set_inode_index(dir, index);
4414 btrfs_free_path(path);
4416 return ERR_PTR(ret);
4420 * index_cnt is ignored for everything but a dir,
4421 * btrfs_get_inode_index_count has an explanation for the magic
4424 BTRFS_I(inode)->index_cnt = 2;
4425 BTRFS_I(inode)->root = root;
4426 BTRFS_I(inode)->generation = trans->transid;
4427 inode->i_generation = BTRFS_I(inode)->generation;
4428 btrfs_set_inode_space_info(root, inode);
4435 key[0].objectid = objectid;
4436 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
4439 key[1].objectid = objectid;
4440 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
4441 key[1].offset = ref_objectid;
4443 sizes[0] = sizeof(struct btrfs_inode_item);
4444 sizes[1] = name_len + sizeof(*ref);
4446 path->leave_spinning = 1;
4447 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
4451 inode_init_owner(inode, dir, mode);
4452 inode_set_bytes(inode, 0);
4453 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
4454 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
4455 struct btrfs_inode_item);
4456 fill_inode_item(trans, path->nodes[0], inode_item, inode);
4458 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
4459 struct btrfs_inode_ref);
4460 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
4461 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
4462 ptr = (unsigned long)(ref + 1);
4463 write_extent_buffer(path->nodes[0], name, ptr, name_len);
4465 btrfs_mark_buffer_dirty(path->nodes[0]);
4466 btrfs_free_path(path);
4468 location = &BTRFS_I(inode)->location;
4469 location->objectid = objectid;
4470 location->offset = 0;
4471 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
4473 btrfs_inherit_iflags(inode, dir);
4475 if (S_ISREG(mode)) {
4476 if (btrfs_test_opt(root, NODATASUM))
4477 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
4478 if (btrfs_test_opt(root, NODATACOW) ||
4479 (BTRFS_I(dir)->flags & BTRFS_INODE_NODATACOW))
4480 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
4483 insert_inode_hash(inode);
4484 inode_tree_add(inode);
4486 trace_btrfs_inode_new(inode);
4487 btrfs_set_inode_last_trans(trans, inode);
4492 BTRFS_I(dir)->index_cnt--;
4493 btrfs_free_path(path);
4495 return ERR_PTR(ret);
4498 static inline u8 btrfs_inode_type(struct inode *inode)
4500 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
4504 * utility function to add 'inode' into 'parent_inode' with
4505 * a give name and a given sequence number.
4506 * if 'add_backref' is true, also insert a backref from the
4507 * inode to the parent directory.
4509 int btrfs_add_link(struct btrfs_trans_handle *trans,
4510 struct inode *parent_inode, struct inode *inode,
4511 const char *name, int name_len, int add_backref, u64 index)
4514 struct btrfs_key key;
4515 struct btrfs_root *root = BTRFS_I(parent_inode)->root;
4516 u64 ino = btrfs_ino(inode);
4517 u64 parent_ino = btrfs_ino(parent_inode);
4519 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
4520 memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key));
4523 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
4527 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
4528 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
4529 key.objectid, root->root_key.objectid,
4530 parent_ino, index, name, name_len);
4531 } else if (add_backref) {
4532 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino,
4537 ret = btrfs_insert_dir_item(trans, root, name, name_len,
4539 btrfs_inode_type(inode), index);
4542 btrfs_i_size_write(parent_inode, parent_inode->i_size +
4544 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
4545 ret = btrfs_update_inode(trans, root, parent_inode);
4550 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
4551 struct inode *dir, struct dentry *dentry,
4552 struct inode *inode, int backref, u64 index)
4554 int err = btrfs_add_link(trans, dir, inode,
4555 dentry->d_name.name, dentry->d_name.len,
4558 d_instantiate(dentry, inode);
4566 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
4567 int mode, dev_t rdev)
4569 struct btrfs_trans_handle *trans;
4570 struct btrfs_root *root = BTRFS_I(dir)->root;
4571 struct inode *inode = NULL;
4575 unsigned long nr = 0;
4578 if (!new_valid_dev(rdev))
4582 * 2 for inode item and ref
4584 * 1 for xattr if selinux is on
4586 trans = btrfs_start_transaction(root, 5);
4588 return PTR_ERR(trans);
4590 err = btrfs_find_free_ino(root, &objectid);
4594 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4595 dentry->d_name.len, btrfs_ino(dir), objectid,
4597 if (IS_ERR(inode)) {
4598 err = PTR_ERR(inode);
4602 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4608 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
4612 inode->i_op = &btrfs_special_inode_operations;
4613 init_special_inode(inode, inode->i_mode, rdev);
4614 btrfs_update_inode(trans, root, inode);
4617 nr = trans->blocks_used;
4618 btrfs_end_transaction_throttle(trans, root);
4619 btrfs_btree_balance_dirty(root, nr);
4621 inode_dec_link_count(inode);
4627 static int btrfs_create(struct inode *dir, struct dentry *dentry,
4628 int mode, struct nameidata *nd)
4630 struct btrfs_trans_handle *trans;
4631 struct btrfs_root *root = BTRFS_I(dir)->root;
4632 struct inode *inode = NULL;
4635 unsigned long nr = 0;
4640 * 2 for inode item and ref
4642 * 1 for xattr if selinux is on
4644 trans = btrfs_start_transaction(root, 5);
4646 return PTR_ERR(trans);
4648 err = btrfs_find_free_ino(root, &objectid);
4652 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4653 dentry->d_name.len, btrfs_ino(dir), objectid,
4655 if (IS_ERR(inode)) {
4656 err = PTR_ERR(inode);
4660 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4666 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
4670 inode->i_mapping->a_ops = &btrfs_aops;
4671 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
4672 inode->i_fop = &btrfs_file_operations;
4673 inode->i_op = &btrfs_file_inode_operations;
4674 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
4677 nr = trans->blocks_used;
4678 btrfs_end_transaction_throttle(trans, root);
4680 inode_dec_link_count(inode);
4683 btrfs_btree_balance_dirty(root, nr);
4687 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
4688 struct dentry *dentry)
4690 struct btrfs_trans_handle *trans;
4691 struct btrfs_root *root = BTRFS_I(dir)->root;
4692 struct inode *inode = old_dentry->d_inode;
4694 unsigned long nr = 0;
4698 /* do not allow sys_link's with other subvols of the same device */
4699 if (root->objectid != BTRFS_I(inode)->root->objectid)
4702 if (inode->i_nlink == ~0U)
4705 err = btrfs_set_inode_index(dir, &index);
4710 * 2 items for inode and inode ref
4711 * 2 items for dir items
4712 * 1 item for parent inode
4714 trans = btrfs_start_transaction(root, 5);
4715 if (IS_ERR(trans)) {
4716 err = PTR_ERR(trans);
4720 btrfs_inc_nlink(inode);
4721 inode->i_ctime = CURRENT_TIME;
4724 err = btrfs_add_nondir(trans, dir, dentry, inode, 1, index);
4729 struct dentry *parent = dentry->d_parent;
4730 err = btrfs_update_inode(trans, root, inode);
4732 btrfs_log_new_name(trans, inode, NULL, parent);
4735 nr = trans->blocks_used;
4736 btrfs_end_transaction_throttle(trans, root);
4739 inode_dec_link_count(inode);
4742 btrfs_btree_balance_dirty(root, nr);
4746 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
4748 struct inode *inode = NULL;
4749 struct btrfs_trans_handle *trans;
4750 struct btrfs_root *root = BTRFS_I(dir)->root;
4752 int drop_on_err = 0;
4755 unsigned long nr = 1;
4758 * 2 items for inode and ref
4759 * 2 items for dir items
4760 * 1 for xattr if selinux is on
4762 trans = btrfs_start_transaction(root, 5);
4764 return PTR_ERR(trans);
4766 err = btrfs_find_free_ino(root, &objectid);
4770 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4771 dentry->d_name.len, btrfs_ino(dir), objectid,
4772 S_IFDIR | mode, &index);
4773 if (IS_ERR(inode)) {
4774 err = PTR_ERR(inode);
4780 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4784 inode->i_op = &btrfs_dir_inode_operations;
4785 inode->i_fop = &btrfs_dir_file_operations;
4787 btrfs_i_size_write(inode, 0);
4788 err = btrfs_update_inode(trans, root, inode);
4792 err = btrfs_add_link(trans, dir, inode, dentry->d_name.name,
4793 dentry->d_name.len, 0, index);
4797 d_instantiate(dentry, inode);
4801 nr = trans->blocks_used;
4802 btrfs_end_transaction_throttle(trans, root);
4805 btrfs_btree_balance_dirty(root, nr);
4809 /* helper for btfs_get_extent. Given an existing extent in the tree,
4810 * and an extent that you want to insert, deal with overlap and insert
4811 * the new extent into the tree.
4813 static int merge_extent_mapping(struct extent_map_tree *em_tree,
4814 struct extent_map *existing,
4815 struct extent_map *em,
4816 u64 map_start, u64 map_len)
4820 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
4821 start_diff = map_start - em->start;
4822 em->start = map_start;
4824 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
4825 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
4826 em->block_start += start_diff;
4827 em->block_len -= start_diff;
4829 return add_extent_mapping(em_tree, em);
4832 static noinline int uncompress_inline(struct btrfs_path *path,
4833 struct inode *inode, struct page *page,
4834 size_t pg_offset, u64 extent_offset,
4835 struct btrfs_file_extent_item *item)
4838 struct extent_buffer *leaf = path->nodes[0];
4841 unsigned long inline_size;
4845 WARN_ON(pg_offset != 0);
4846 compress_type = btrfs_file_extent_compression(leaf, item);
4847 max_size = btrfs_file_extent_ram_bytes(leaf, item);
4848 inline_size = btrfs_file_extent_inline_item_len(leaf,
4849 btrfs_item_nr(leaf, path->slots[0]));
4850 tmp = kmalloc(inline_size, GFP_NOFS);
4853 ptr = btrfs_file_extent_inline_start(item);
4855 read_extent_buffer(leaf, tmp, ptr, inline_size);
4857 max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size);
4858 ret = btrfs_decompress(compress_type, tmp, page,
4859 extent_offset, inline_size, max_size);
4861 char *kaddr = kmap_atomic(page, KM_USER0);
4862 unsigned long copy_size = min_t(u64,
4863 PAGE_CACHE_SIZE - pg_offset,
4864 max_size - extent_offset);
4865 memset(kaddr + pg_offset, 0, copy_size);
4866 kunmap_atomic(kaddr, KM_USER0);
4873 * a bit scary, this does extent mapping from logical file offset to the disk.
4874 * the ugly parts come from merging extents from the disk with the in-ram
4875 * representation. This gets more complex because of the data=ordered code,
4876 * where the in-ram extents might be locked pending data=ordered completion.
4878 * This also copies inline extents directly into the page.
4881 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
4882 size_t pg_offset, u64 start, u64 len,
4888 u64 extent_start = 0;
4890 u64 objectid = btrfs_ino(inode);
4892 struct btrfs_path *path = NULL;
4893 struct btrfs_root *root = BTRFS_I(inode)->root;
4894 struct btrfs_file_extent_item *item;
4895 struct extent_buffer *leaf;
4896 struct btrfs_key found_key;
4897 struct extent_map *em = NULL;
4898 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
4899 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4900 struct btrfs_trans_handle *trans = NULL;
4904 read_lock(&em_tree->lock);
4905 em = lookup_extent_mapping(em_tree, start, len);
4907 em->bdev = root->fs_info->fs_devices->latest_bdev;
4908 read_unlock(&em_tree->lock);
4911 if (em->start > start || em->start + em->len <= start)
4912 free_extent_map(em);
4913 else if (em->block_start == EXTENT_MAP_INLINE && page)
4914 free_extent_map(em);
4918 em = alloc_extent_map();
4923 em->bdev = root->fs_info->fs_devices->latest_bdev;
4924 em->start = EXTENT_MAP_HOLE;
4925 em->orig_start = EXTENT_MAP_HOLE;
4927 em->block_len = (u64)-1;
4930 path = btrfs_alloc_path();
4936 * Chances are we'll be called again, so go ahead and do
4942 ret = btrfs_lookup_file_extent(trans, root, path,
4943 objectid, start, trans != NULL);
4950 if (path->slots[0] == 0)
4955 leaf = path->nodes[0];
4956 item = btrfs_item_ptr(leaf, path->slots[0],
4957 struct btrfs_file_extent_item);
4958 /* are we inside the extent that was found? */
4959 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4960 found_type = btrfs_key_type(&found_key);
4961 if (found_key.objectid != objectid ||
4962 found_type != BTRFS_EXTENT_DATA_KEY) {
4966 found_type = btrfs_file_extent_type(leaf, item);
4967 extent_start = found_key.offset;
4968 compress_type = btrfs_file_extent_compression(leaf, item);
4969 if (found_type == BTRFS_FILE_EXTENT_REG ||
4970 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
4971 extent_end = extent_start +
4972 btrfs_file_extent_num_bytes(leaf, item);
4973 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
4975 size = btrfs_file_extent_inline_len(leaf, item);
4976 extent_end = (extent_start + size + root->sectorsize - 1) &
4977 ~((u64)root->sectorsize - 1);
4980 if (start >= extent_end) {
4982 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
4983 ret = btrfs_next_leaf(root, path);
4990 leaf = path->nodes[0];
4992 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4993 if (found_key.objectid != objectid ||
4994 found_key.type != BTRFS_EXTENT_DATA_KEY)
4996 if (start + len <= found_key.offset)
4999 em->len = found_key.offset - start;
5003 if (found_type == BTRFS_FILE_EXTENT_REG ||
5004 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
5005 em->start = extent_start;
5006 em->len = extent_end - extent_start;
5007 em->orig_start = extent_start -
5008 btrfs_file_extent_offset(leaf, item);
5009 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
5011 em->block_start = EXTENT_MAP_HOLE;
5014 if (compress_type != BTRFS_COMPRESS_NONE) {
5015 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
5016 em->compress_type = compress_type;
5017 em->block_start = bytenr;
5018 em->block_len = btrfs_file_extent_disk_num_bytes(leaf,
5021 bytenr += btrfs_file_extent_offset(leaf, item);
5022 em->block_start = bytenr;
5023 em->block_len = em->len;
5024 if (found_type == BTRFS_FILE_EXTENT_PREALLOC)
5025 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
5028 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
5032 size_t extent_offset;
5035 em->block_start = EXTENT_MAP_INLINE;
5036 if (!page || create) {
5037 em->start = extent_start;
5038 em->len = extent_end - extent_start;
5042 size = btrfs_file_extent_inline_len(leaf, item);
5043 extent_offset = page_offset(page) + pg_offset - extent_start;
5044 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
5045 size - extent_offset);
5046 em->start = extent_start + extent_offset;
5047 em->len = (copy_size + root->sectorsize - 1) &
5048 ~((u64)root->sectorsize - 1);
5049 em->orig_start = EXTENT_MAP_INLINE;
5050 if (compress_type) {
5051 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
5052 em->compress_type = compress_type;
5054 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
5055 if (create == 0 && !PageUptodate(page)) {
5056 if (btrfs_file_extent_compression(leaf, item) !=
5057 BTRFS_COMPRESS_NONE) {
5058 ret = uncompress_inline(path, inode, page,
5060 extent_offset, item);
5064 read_extent_buffer(leaf, map + pg_offset, ptr,
5066 if (pg_offset + copy_size < PAGE_CACHE_SIZE) {
5067 memset(map + pg_offset + copy_size, 0,
5068 PAGE_CACHE_SIZE - pg_offset -
5073 flush_dcache_page(page);
5074 } else if (create && PageUptodate(page)) {
5078 free_extent_map(em);
5081 btrfs_release_path(path);
5082 trans = btrfs_join_transaction(root);
5085 return ERR_CAST(trans);
5089 write_extent_buffer(leaf, map + pg_offset, ptr,
5092 btrfs_mark_buffer_dirty(leaf);
5094 set_extent_uptodate(io_tree, em->start,
5095 extent_map_end(em) - 1, NULL, GFP_NOFS);
5098 printk(KERN_ERR "btrfs unknown found_type %d\n", found_type);
5105 em->block_start = EXTENT_MAP_HOLE;
5106 set_bit(EXTENT_FLAG_VACANCY, &em->flags);
5108 btrfs_release_path(path);
5109 if (em->start > start || extent_map_end(em) <= start) {
5110 printk(KERN_ERR "Btrfs: bad extent! em: [%llu %llu] passed "
5111 "[%llu %llu]\n", (unsigned long long)em->start,
5112 (unsigned long long)em->len,
5113 (unsigned long long)start,
5114 (unsigned long long)len);
5120 write_lock(&em_tree->lock);
5121 ret = add_extent_mapping(em_tree, em);
5122 /* it is possible that someone inserted the extent into the tree
5123 * while we had the lock dropped. It is also possible that
5124 * an overlapping map exists in the tree
5126 if (ret == -EEXIST) {
5127 struct extent_map *existing;
5131 existing = lookup_extent_mapping(em_tree, start, len);
5132 if (existing && (existing->start > start ||
5133 existing->start + existing->len <= start)) {
5134 free_extent_map(existing);
5138 existing = lookup_extent_mapping(em_tree, em->start,
5141 err = merge_extent_mapping(em_tree, existing,
5144 free_extent_map(existing);
5146 free_extent_map(em);
5151 free_extent_map(em);
5155 free_extent_map(em);
5160 write_unlock(&em_tree->lock);
5163 trace_btrfs_get_extent(root, em);
5166 btrfs_free_path(path);
5168 ret = btrfs_end_transaction(trans, root);
5173 free_extent_map(em);
5174 return ERR_PTR(err);
5179 struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page,
5180 size_t pg_offset, u64 start, u64 len,
5183 struct extent_map *em;
5184 struct extent_map *hole_em = NULL;
5185 u64 range_start = start;
5191 em = btrfs_get_extent(inode, page, pg_offset, start, len, create);
5196 * if our em maps to a hole, there might
5197 * actually be delalloc bytes behind it
5199 if (em->block_start != EXTENT_MAP_HOLE)
5205 /* check to see if we've wrapped (len == -1 or similar) */
5214 /* ok, we didn't find anything, lets look for delalloc */
5215 found = count_range_bits(&BTRFS_I(inode)->io_tree, &range_start,
5216 end, len, EXTENT_DELALLOC, 1);
5217 found_end = range_start + found;
5218 if (found_end < range_start)
5219 found_end = (u64)-1;
5222 * we didn't find anything useful, return
5223 * the original results from get_extent()
5225 if (range_start > end || found_end <= start) {
5231 /* adjust the range_start to make sure it doesn't
5232 * go backwards from the start they passed in
5234 range_start = max(start,range_start);
5235 found = found_end - range_start;
5238 u64 hole_start = start;
5241 em = alloc_extent_map();
5247 * when btrfs_get_extent can't find anything it
5248 * returns one huge hole
5250 * make sure what it found really fits our range, and
5251 * adjust to make sure it is based on the start from
5255 u64 calc_end = extent_map_end(hole_em);
5257 if (calc_end <= start || (hole_em->start > end)) {
5258 free_extent_map(hole_em);
5261 hole_start = max(hole_em->start, start);
5262 hole_len = calc_end - hole_start;
5266 if (hole_em && range_start > hole_start) {
5267 /* our hole starts before our delalloc, so we
5268 * have to return just the parts of the hole
5269 * that go until the delalloc starts
5271 em->len = min(hole_len,
5272 range_start - hole_start);
5273 em->start = hole_start;
5274 em->orig_start = hole_start;
5276 * don't adjust block start at all,
5277 * it is fixed at EXTENT_MAP_HOLE
5279 em->block_start = hole_em->block_start;
5280 em->block_len = hole_len;
5282 em->start = range_start;
5284 em->orig_start = range_start;
5285 em->block_start = EXTENT_MAP_DELALLOC;
5286 em->block_len = found;
5288 } else if (hole_em) {
5293 free_extent_map(hole_em);
5295 free_extent_map(em);
5296 return ERR_PTR(err);
5301 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
5302 struct extent_map *em,
5305 struct btrfs_root *root = BTRFS_I(inode)->root;
5306 struct btrfs_trans_handle *trans;
5307 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
5308 struct btrfs_key ins;
5311 bool insert = false;
5314 * Ok if the extent map we looked up is a hole and is for the exact
5315 * range we want, there is no reason to allocate a new one, however if
5316 * it is not right then we need to free this one and drop the cache for
5319 if (em->block_start != EXTENT_MAP_HOLE || em->start != start ||
5321 free_extent_map(em);
5324 btrfs_drop_extent_cache(inode, start, start + len - 1, 0);
5327 trans = btrfs_join_transaction(root);
5329 return ERR_CAST(trans);
5331 if (start <= BTRFS_I(inode)->disk_i_size && len < 64 * 1024)
5332 btrfs_add_inode_defrag(trans, inode);
5334 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
5336 alloc_hint = get_extent_allocation_hint(inode, start, len);
5337 ret = btrfs_reserve_extent(trans, root, len, root->sectorsize, 0,
5338 alloc_hint, (u64)-1, &ins, 1);
5345 em = alloc_extent_map();
5347 em = ERR_PTR(-ENOMEM);
5353 em->orig_start = em->start;
5354 em->len = ins.offset;
5356 em->block_start = ins.objectid;
5357 em->block_len = ins.offset;
5358 em->bdev = root->fs_info->fs_devices->latest_bdev;
5361 * We need to do this because if we're using the original em we searched
5362 * for, we could have EXTENT_FLAG_VACANCY set, and we don't want that.
5365 set_bit(EXTENT_FLAG_PINNED, &em->flags);
5368 write_lock(&em_tree->lock);
5369 ret = add_extent_mapping(em_tree, em);
5370 write_unlock(&em_tree->lock);
5373 btrfs_drop_extent_cache(inode, start, start + em->len - 1, 0);
5376 ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
5377 ins.offset, ins.offset, 0);
5379 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
5383 btrfs_end_transaction(trans, root);
5388 * returns 1 when the nocow is safe, < 1 on error, 0 if the
5389 * block must be cow'd
5391 static noinline int can_nocow_odirect(struct btrfs_trans_handle *trans,
5392 struct inode *inode, u64 offset, u64 len)
5394 struct btrfs_path *path;
5396 struct extent_buffer *leaf;
5397 struct btrfs_root *root = BTRFS_I(inode)->root;
5398 struct btrfs_file_extent_item *fi;
5399 struct btrfs_key key;
5407 path = btrfs_alloc_path();
5411 ret = btrfs_lookup_file_extent(trans, root, path, btrfs_ino(inode),
5416 slot = path->slots[0];
5419 /* can't find the item, must cow */
5426 leaf = path->nodes[0];
5427 btrfs_item_key_to_cpu(leaf, &key, slot);
5428 if (key.objectid != btrfs_ino(inode) ||
5429 key.type != BTRFS_EXTENT_DATA_KEY) {
5430 /* not our file or wrong item type, must cow */
5434 if (key.offset > offset) {
5435 /* Wrong offset, must cow */
5439 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
5440 found_type = btrfs_file_extent_type(leaf, fi);
5441 if (found_type != BTRFS_FILE_EXTENT_REG &&
5442 found_type != BTRFS_FILE_EXTENT_PREALLOC) {
5443 /* not a regular extent, must cow */
5446 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
5447 backref_offset = btrfs_file_extent_offset(leaf, fi);
5449 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
5450 if (extent_end < offset + len) {
5451 /* extent doesn't include our full range, must cow */
5455 if (btrfs_extent_readonly(root, disk_bytenr))
5459 * look for other files referencing this extent, if we
5460 * find any we must cow
5462 if (btrfs_cross_ref_exist(trans, root, btrfs_ino(inode),
5463 key.offset - backref_offset, disk_bytenr))
5467 * adjust disk_bytenr and num_bytes to cover just the bytes
5468 * in this extent we are about to write. If there
5469 * are any csums in that range we have to cow in order
5470 * to keep the csums correct
5472 disk_bytenr += backref_offset;
5473 disk_bytenr += offset - key.offset;
5474 num_bytes = min(offset + len, extent_end) - offset;
5475 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
5478 * all of the above have passed, it is safe to overwrite this extent
5483 btrfs_free_path(path);
5487 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
5488 struct buffer_head *bh_result, int create)
5490 struct extent_map *em;
5491 struct btrfs_root *root = BTRFS_I(inode)->root;
5492 u64 start = iblock << inode->i_blkbits;
5493 u64 len = bh_result->b_size;
5494 struct btrfs_trans_handle *trans;
5496 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
5501 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered
5502 * io. INLINE is special, and we could probably kludge it in here, but
5503 * it's still buffered so for safety lets just fall back to the generic
5506 * For COMPRESSED we _have_ to read the entire extent in so we can
5507 * decompress it, so there will be buffering required no matter what we
5508 * do, so go ahead and fallback to buffered.
5510 * We return -ENOTBLK because thats what makes DIO go ahead and go back
5511 * to buffered IO. Don't blame me, this is the price we pay for using
5514 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
5515 em->block_start == EXTENT_MAP_INLINE) {
5516 free_extent_map(em);
5520 /* Just a good old fashioned hole, return */
5521 if (!create && (em->block_start == EXTENT_MAP_HOLE ||
5522 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
5523 free_extent_map(em);
5524 /* DIO will do one hole at a time, so just unlock a sector */
5525 unlock_extent(&BTRFS_I(inode)->io_tree, start,
5526 start + root->sectorsize - 1, GFP_NOFS);
5531 * We don't allocate a new extent in the following cases
5533 * 1) The inode is marked as NODATACOW. In this case we'll just use the
5535 * 2) The extent is marked as PREALLOC. We're good to go here and can
5536 * just use the extent.
5540 len = em->len - (start - em->start);
5544 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
5545 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
5546 em->block_start != EXTENT_MAP_HOLE)) {
5551 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
5552 type = BTRFS_ORDERED_PREALLOC;
5554 type = BTRFS_ORDERED_NOCOW;
5555 len = min(len, em->len - (start - em->start));
5556 block_start = em->block_start + (start - em->start);
5559 * we're not going to log anything, but we do need
5560 * to make sure the current transaction stays open
5561 * while we look for nocow cross refs
5563 trans = btrfs_join_transaction(root);
5567 if (can_nocow_odirect(trans, inode, start, len) == 1) {
5568 ret = btrfs_add_ordered_extent_dio(inode, start,
5569 block_start, len, len, type);
5570 btrfs_end_transaction(trans, root);
5572 free_extent_map(em);
5577 btrfs_end_transaction(trans, root);
5581 * this will cow the extent, reset the len in case we changed
5584 len = bh_result->b_size;
5585 em = btrfs_new_extent_direct(inode, em, start, len);
5588 len = min(len, em->len - (start - em->start));
5590 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, start + len - 1,
5591 EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DIRTY, 1,
5594 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
5596 bh_result->b_size = len;
5597 bh_result->b_bdev = em->bdev;
5598 set_buffer_mapped(bh_result);
5599 if (create && !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
5600 set_buffer_new(bh_result);
5602 free_extent_map(em);
5607 struct btrfs_dio_private {
5608 struct inode *inode;
5615 /* number of bios pending for this dio */
5616 atomic_t pending_bios;
5621 struct bio *orig_bio;
5624 static void btrfs_endio_direct_read(struct bio *bio, int err)
5626 struct btrfs_dio_private *dip = bio->bi_private;
5627 struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
5628 struct bio_vec *bvec = bio->bi_io_vec;
5629 struct inode *inode = dip->inode;
5630 struct btrfs_root *root = BTRFS_I(inode)->root;
5632 u32 *private = dip->csums;
5634 start = dip->logical_offset;
5636 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
5637 struct page *page = bvec->bv_page;
5640 unsigned long flags;
5642 local_irq_save(flags);
5643 kaddr = kmap_atomic(page, KM_IRQ0);
5644 csum = btrfs_csum_data(root, kaddr + bvec->bv_offset,
5645 csum, bvec->bv_len);
5646 btrfs_csum_final(csum, (char *)&csum);
5647 kunmap_atomic(kaddr, KM_IRQ0);
5648 local_irq_restore(flags);
5650 flush_dcache_page(bvec->bv_page);
5651 if (csum != *private) {
5652 printk(KERN_ERR "btrfs csum failed ino %llu off"
5653 " %llu csum %u private %u\n",
5654 (unsigned long long)btrfs_ino(inode),
5655 (unsigned long long)start,
5661 start += bvec->bv_len;
5664 } while (bvec <= bvec_end);
5666 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
5667 dip->logical_offset + dip->bytes - 1, GFP_NOFS);
5668 bio->bi_private = dip->private;
5673 /* If we had a csum failure make sure to clear the uptodate flag */
5675 clear_bit(BIO_UPTODATE, &bio->bi_flags);
5676 dio_end_io(bio, err);
5679 static void btrfs_endio_direct_write(struct bio *bio, int err)
5681 struct btrfs_dio_private *dip = bio->bi_private;
5682 struct inode *inode = dip->inode;
5683 struct btrfs_root *root = BTRFS_I(inode)->root;
5684 struct btrfs_trans_handle *trans;
5685 struct btrfs_ordered_extent *ordered = NULL;
5686 struct extent_state *cached_state = NULL;
5687 u64 ordered_offset = dip->logical_offset;
5688 u64 ordered_bytes = dip->bytes;
5694 ret = btrfs_dec_test_first_ordered_pending(inode, &ordered,
5702 trans = btrfs_join_transaction(root);
5703 if (IS_ERR(trans)) {
5707 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
5709 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags)) {
5710 ret = btrfs_ordered_update_i_size(inode, 0, ordered);
5712 ret = btrfs_update_inode(trans, root, inode);
5717 lock_extent_bits(&BTRFS_I(inode)->io_tree, ordered->file_offset,
5718 ordered->file_offset + ordered->len - 1, 0,
5719 &cached_state, GFP_NOFS);
5721 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags)) {
5722 ret = btrfs_mark_extent_written(trans, inode,
5723 ordered->file_offset,
5724 ordered->file_offset +
5731 ret = insert_reserved_file_extent(trans, inode,
5732 ordered->file_offset,
5738 BTRFS_FILE_EXTENT_REG);
5739 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
5740 ordered->file_offset, ordered->len);
5748 add_pending_csums(trans, inode, ordered->file_offset, &ordered->list);
5749 ret = btrfs_ordered_update_i_size(inode, 0, ordered);
5750 if (!ret || !test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags))
5751 btrfs_update_inode(trans, root, inode);
5754 unlock_extent_cached(&BTRFS_I(inode)->io_tree, ordered->file_offset,
5755 ordered->file_offset + ordered->len - 1,
5756 &cached_state, GFP_NOFS);
5758 btrfs_delalloc_release_metadata(inode, ordered->len);
5759 btrfs_end_transaction(trans, root);
5760 ordered_offset = ordered->file_offset + ordered->len;
5761 btrfs_put_ordered_extent(ordered);
5762 btrfs_put_ordered_extent(ordered);
5766 * our bio might span multiple ordered extents. If we haven't
5767 * completed the accounting for the whole dio, go back and try again
5769 if (ordered_offset < dip->logical_offset + dip->bytes) {
5770 ordered_bytes = dip->logical_offset + dip->bytes -
5775 bio->bi_private = dip->private;
5780 /* If we had an error make sure to clear the uptodate flag */
5782 clear_bit(BIO_UPTODATE, &bio->bi_flags);
5783 dio_end_io(bio, err);
5786 static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw,
5787 struct bio *bio, int mirror_num,
5788 unsigned long bio_flags, u64 offset)
5791 struct btrfs_root *root = BTRFS_I(inode)->root;
5792 ret = btrfs_csum_one_bio(root, inode, bio, offset, 1);
5797 static void btrfs_end_dio_bio(struct bio *bio, int err)
5799 struct btrfs_dio_private *dip = bio->bi_private;
5802 printk(KERN_ERR "btrfs direct IO failed ino %llu rw %lu "
5803 "sector %#Lx len %u err no %d\n",
5804 (unsigned long long)btrfs_ino(dip->inode), bio->bi_rw,
5805 (unsigned long long)bio->bi_sector, bio->bi_size, err);
5809 * before atomic variable goto zero, we must make sure
5810 * dip->errors is perceived to be set.
5812 smp_mb__before_atomic_dec();
5815 /* if there are more bios still pending for this dio, just exit */
5816 if (!atomic_dec_and_test(&dip->pending_bios))
5820 bio_io_error(dip->orig_bio);
5822 set_bit(BIO_UPTODATE, &dip->orig_bio->bi_flags);
5823 bio_endio(dip->orig_bio, 0);
5829 static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev,
5830 u64 first_sector, gfp_t gfp_flags)
5832 int nr_vecs = bio_get_nr_vecs(bdev);
5833 return btrfs_bio_alloc(bdev, first_sector, nr_vecs, gfp_flags);
5836 static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode,
5837 int rw, u64 file_offset, int skip_sum,
5838 u32 *csums, int async_submit)
5840 int write = rw & REQ_WRITE;
5841 struct btrfs_root *root = BTRFS_I(inode)->root;
5845 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
5852 if (write && async_submit) {
5853 ret = btrfs_wq_submit_bio(root->fs_info,
5854 inode, rw, bio, 0, 0,
5856 __btrfs_submit_bio_start_direct_io,
5857 __btrfs_submit_bio_done);
5861 * If we aren't doing async submit, calculate the csum of the
5864 ret = btrfs_csum_one_bio(root, inode, bio, file_offset, 1);
5867 } else if (!skip_sum) {
5868 ret = btrfs_lookup_bio_sums_dio(root, inode, bio,
5869 file_offset, csums);
5875 ret = btrfs_map_bio(root, rw, bio, 0, async_submit);
5881 static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip,
5884 struct inode *inode = dip->inode;
5885 struct btrfs_root *root = BTRFS_I(inode)->root;
5886 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
5888 struct bio *orig_bio = dip->orig_bio;
5889 struct bio_vec *bvec = orig_bio->bi_io_vec;
5890 u64 start_sector = orig_bio->bi_sector;
5891 u64 file_offset = dip->logical_offset;
5895 u32 *csums = dip->csums;
5897 int async_submit = 0;
5898 int write = rw & REQ_WRITE;
5900 map_length = orig_bio->bi_size;
5901 ret = btrfs_map_block(map_tree, READ, start_sector << 9,
5902 &map_length, NULL, 0);
5908 if (map_length >= orig_bio->bi_size) {
5914 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS);
5917 bio->bi_private = dip;
5918 bio->bi_end_io = btrfs_end_dio_bio;
5919 atomic_inc(&dip->pending_bios);
5921 while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) {
5922 if (unlikely(map_length < submit_len + bvec->bv_len ||
5923 bio_add_page(bio, bvec->bv_page, bvec->bv_len,
5924 bvec->bv_offset) < bvec->bv_len)) {
5926 * inc the count before we submit the bio so
5927 * we know the end IO handler won't happen before
5928 * we inc the count. Otherwise, the dip might get freed
5929 * before we're done setting it up
5931 atomic_inc(&dip->pending_bios);
5932 ret = __btrfs_submit_dio_bio(bio, inode, rw,
5933 file_offset, skip_sum,
5934 csums, async_submit);
5937 atomic_dec(&dip->pending_bios);
5941 /* Write's use the ordered csums */
5942 if (!write && !skip_sum)
5943 csums = csums + nr_pages;
5944 start_sector += submit_len >> 9;
5945 file_offset += submit_len;
5950 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev,
5951 start_sector, GFP_NOFS);
5954 bio->bi_private = dip;
5955 bio->bi_end_io = btrfs_end_dio_bio;
5957 map_length = orig_bio->bi_size;
5958 ret = btrfs_map_block(map_tree, READ, start_sector << 9,
5959 &map_length, NULL, 0);
5965 submit_len += bvec->bv_len;
5972 ret = __btrfs_submit_dio_bio(bio, inode, rw, file_offset, skip_sum,
5973 csums, async_submit);
5981 * before atomic variable goto zero, we must
5982 * make sure dip->errors is perceived to be set.
5984 smp_mb__before_atomic_dec();
5985 if (atomic_dec_and_test(&dip->pending_bios))
5986 bio_io_error(dip->orig_bio);
5988 /* bio_end_io() will handle error, so we needn't return it */
5992 static void btrfs_submit_direct(int rw, struct bio *bio, struct inode *inode,
5995 struct btrfs_root *root = BTRFS_I(inode)->root;
5996 struct btrfs_dio_private *dip;
5997 struct bio_vec *bvec = bio->bi_io_vec;
5999 int write = rw & REQ_WRITE;
6002 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
6004 dip = kmalloc(sizeof(*dip), GFP_NOFS);
6011 /* Write's use the ordered csum stuff, so we don't need dip->csums */
6012 if (!write && !skip_sum) {
6013 dip->csums = kmalloc(sizeof(u32) * bio->bi_vcnt, GFP_NOFS);
6021 dip->private = bio->bi_private;
6023 dip->logical_offset = file_offset;
6027 dip->bytes += bvec->bv_len;
6029 } while (bvec <= (bio->bi_io_vec + bio->bi_vcnt - 1));
6031 dip->disk_bytenr = (u64)bio->bi_sector << 9;
6032 bio->bi_private = dip;
6034 dip->orig_bio = bio;
6035 atomic_set(&dip->pending_bios, 0);
6038 bio->bi_end_io = btrfs_endio_direct_write;
6040 bio->bi_end_io = btrfs_endio_direct_read;
6042 ret = btrfs_submit_direct_hook(rw, dip, skip_sum);
6047 * If this is a write, we need to clean up the reserved space and kill
6048 * the ordered extent.
6051 struct btrfs_ordered_extent *ordered;
6052 ordered = btrfs_lookup_ordered_extent(inode, file_offset);
6053 if (!test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags) &&
6054 !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags))
6055 btrfs_free_reserved_extent(root, ordered->start,
6057 btrfs_put_ordered_extent(ordered);
6058 btrfs_put_ordered_extent(ordered);
6060 bio_endio(bio, ret);
6063 static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb,
6064 const struct iovec *iov, loff_t offset,
6065 unsigned long nr_segs)
6071 unsigned blocksize_mask = root->sectorsize - 1;
6072 ssize_t retval = -EINVAL;
6073 loff_t end = offset;
6075 if (offset & blocksize_mask)
6078 /* Check the memory alignment. Blocks cannot straddle pages */
6079 for (seg = 0; seg < nr_segs; seg++) {
6080 addr = (unsigned long)iov[seg].iov_base;
6081 size = iov[seg].iov_len;
6083 if ((addr & blocksize_mask) || (size & blocksize_mask))
6086 /* If this is a write we don't need to check anymore */
6091 * Check to make sure we don't have duplicate iov_base's in this
6092 * iovec, if so return EINVAL, otherwise we'll get csum errors
6093 * when reading back.
6095 for (i = seg + 1; i < nr_segs; i++) {
6096 if (iov[seg].iov_base == iov[i].iov_base)
6104 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
6105 const struct iovec *iov, loff_t offset,
6106 unsigned long nr_segs)
6108 struct file *file = iocb->ki_filp;
6109 struct inode *inode = file->f_mapping->host;
6110 struct btrfs_ordered_extent *ordered;
6111 struct extent_state *cached_state = NULL;
6112 u64 lockstart, lockend;
6114 int writing = rw & WRITE;
6116 size_t count = iov_length(iov, nr_segs);
6118 if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov,
6124 lockend = offset + count - 1;
6127 ret = btrfs_delalloc_reserve_space(inode, count);
6133 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6134 0, &cached_state, GFP_NOFS);
6136 * We're concerned with the entire range that we're going to be
6137 * doing DIO to, so we need to make sure theres no ordered
6138 * extents in this range.
6140 ordered = btrfs_lookup_ordered_range(inode, lockstart,
6141 lockend - lockstart + 1);
6144 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6145 &cached_state, GFP_NOFS);
6146 btrfs_start_ordered_extent(inode, ordered, 1);
6147 btrfs_put_ordered_extent(ordered);
6152 * we don't use btrfs_set_extent_delalloc because we don't want
6153 * the dirty or uptodate bits
6156 write_bits = EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING;
6157 ret = set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6158 EXTENT_DELALLOC, 0, NULL, &cached_state,
6161 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6162 lockend, EXTENT_LOCKED | write_bits,
6163 1, 0, &cached_state, GFP_NOFS);
6168 free_extent_state(cached_state);
6169 cached_state = NULL;
6171 ret = __blockdev_direct_IO(rw, iocb, inode,
6172 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev,
6173 iov, offset, nr_segs, btrfs_get_blocks_direct, NULL,
6174 btrfs_submit_direct, 0);
6176 if (ret < 0 && ret != -EIOCBQUEUED) {
6177 clear_extent_bit(&BTRFS_I(inode)->io_tree, offset,
6178 offset + iov_length(iov, nr_segs) - 1,
6179 EXTENT_LOCKED | write_bits, 1, 0,
6180 &cached_state, GFP_NOFS);
6181 } else if (ret >= 0 && ret < iov_length(iov, nr_segs)) {
6183 * We're falling back to buffered, unlock the section we didn't
6186 clear_extent_bit(&BTRFS_I(inode)->io_tree, offset + ret,
6187 offset + iov_length(iov, nr_segs) - 1,
6188 EXTENT_LOCKED | write_bits, 1, 0,
6189 &cached_state, GFP_NOFS);
6192 free_extent_state(cached_state);
6196 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
6197 __u64 start, __u64 len)
6199 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap);
6202 int btrfs_readpage(struct file *file, struct page *page)
6204 struct extent_io_tree *tree;
6205 tree = &BTRFS_I(page->mapping->host)->io_tree;
6206 return extent_read_full_page(tree, page, btrfs_get_extent);
6209 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
6211 struct extent_io_tree *tree;
6214 if (current->flags & PF_MEMALLOC) {
6215 redirty_page_for_writepage(wbc, page);
6219 tree = &BTRFS_I(page->mapping->host)->io_tree;
6220 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
6223 int btrfs_writepages(struct address_space *mapping,
6224 struct writeback_control *wbc)
6226 struct extent_io_tree *tree;
6228 tree = &BTRFS_I(mapping->host)->io_tree;
6229 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
6233 btrfs_readpages(struct file *file, struct address_space *mapping,
6234 struct list_head *pages, unsigned nr_pages)
6236 struct extent_io_tree *tree;
6237 tree = &BTRFS_I(mapping->host)->io_tree;
6238 return extent_readpages(tree, mapping, pages, nr_pages,
6241 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
6243 struct extent_io_tree *tree;
6244 struct extent_map_tree *map;
6247 tree = &BTRFS_I(page->mapping->host)->io_tree;
6248 map = &BTRFS_I(page->mapping->host)->extent_tree;
6249 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
6251 ClearPagePrivate(page);
6252 set_page_private(page, 0);
6253 page_cache_release(page);
6258 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
6260 if (PageWriteback(page) || PageDirty(page))
6262 return __btrfs_releasepage(page, gfp_flags & GFP_NOFS);
6265 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
6267 struct extent_io_tree *tree;
6268 struct btrfs_ordered_extent *ordered;
6269 struct extent_state *cached_state = NULL;
6270 u64 page_start = page_offset(page);
6271 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
6275 * we have the page locked, so new writeback can't start,
6276 * and the dirty bit won't be cleared while we are here.
6278 * Wait for IO on this page so that we can safely clear
6279 * the PagePrivate2 bit and do ordered accounting
6281 wait_on_page_writeback(page);
6283 tree = &BTRFS_I(page->mapping->host)->io_tree;
6285 btrfs_releasepage(page, GFP_NOFS);
6288 lock_extent_bits(tree, page_start, page_end, 0, &cached_state,
6290 ordered = btrfs_lookup_ordered_extent(page->mapping->host,
6294 * IO on this page will never be started, so we need
6295 * to account for any ordered extents now
6297 clear_extent_bit(tree, page_start, page_end,
6298 EXTENT_DIRTY | EXTENT_DELALLOC |
6299 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING, 1, 0,
6300 &cached_state, GFP_NOFS);
6302 * whoever cleared the private bit is responsible
6303 * for the finish_ordered_io
6305 if (TestClearPagePrivate2(page)) {
6306 btrfs_finish_ordered_io(page->mapping->host,
6307 page_start, page_end);
6309 btrfs_put_ordered_extent(ordered);
6310 cached_state = NULL;
6311 lock_extent_bits(tree, page_start, page_end, 0, &cached_state,
6314 clear_extent_bit(tree, page_start, page_end,
6315 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
6316 EXTENT_DO_ACCOUNTING, 1, 1, &cached_state, GFP_NOFS);
6317 __btrfs_releasepage(page, GFP_NOFS);
6319 ClearPageChecked(page);
6320 if (PagePrivate(page)) {
6321 ClearPagePrivate(page);
6322 set_page_private(page, 0);
6323 page_cache_release(page);
6328 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
6329 * called from a page fault handler when a page is first dirtied. Hence we must
6330 * be careful to check for EOF conditions here. We set the page up correctly
6331 * for a written page which means we get ENOSPC checking when writing into
6332 * holes and correct delalloc and unwritten extent mapping on filesystems that
6333 * support these features.
6335 * We are not allowed to take the i_mutex here so we have to play games to
6336 * protect against truncate races as the page could now be beyond EOF. Because
6337 * vmtruncate() writes the inode size before removing pages, once we have the
6338 * page lock we can determine safely if the page is beyond EOF. If it is not
6339 * beyond EOF, then the page is guaranteed safe against truncation until we
6342 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
6344 struct page *page = vmf->page;
6345 struct inode *inode = fdentry(vma->vm_file)->d_inode;
6346 struct btrfs_root *root = BTRFS_I(inode)->root;
6347 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6348 struct btrfs_ordered_extent *ordered;
6349 struct extent_state *cached_state = NULL;
6351 unsigned long zero_start;
6357 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
6361 else /* -ENOSPC, -EIO, etc */
6362 ret = VM_FAULT_SIGBUS;
6366 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
6369 size = i_size_read(inode);
6370 page_start = page_offset(page);
6371 page_end = page_start + PAGE_CACHE_SIZE - 1;
6373 if ((page->mapping != inode->i_mapping) ||
6374 (page_start >= size)) {
6375 /* page got truncated out from underneath us */
6378 wait_on_page_writeback(page);
6380 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state,
6382 set_page_extent_mapped(page);
6385 * we can't set the delalloc bits if there are pending ordered
6386 * extents. Drop our locks and wait for them to finish
6388 ordered = btrfs_lookup_ordered_extent(inode, page_start);
6390 unlock_extent_cached(io_tree, page_start, page_end,
6391 &cached_state, GFP_NOFS);
6393 btrfs_start_ordered_extent(inode, ordered, 1);
6394 btrfs_put_ordered_extent(ordered);
6399 * XXX - page_mkwrite gets called every time the page is dirtied, even
6400 * if it was already dirty, so for space accounting reasons we need to
6401 * clear any delalloc bits for the range we are fixing to save. There
6402 * is probably a better way to do this, but for now keep consistent with
6403 * prepare_pages in the normal write path.
6405 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
6406 EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
6407 0, 0, &cached_state, GFP_NOFS);
6409 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
6412 unlock_extent_cached(io_tree, page_start, page_end,
6413 &cached_state, GFP_NOFS);
6414 ret = VM_FAULT_SIGBUS;
6419 /* page is wholly or partially inside EOF */
6420 if (page_start + PAGE_CACHE_SIZE > size)
6421 zero_start = size & ~PAGE_CACHE_MASK;
6423 zero_start = PAGE_CACHE_SIZE;
6425 if (zero_start != PAGE_CACHE_SIZE) {
6427 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
6428 flush_dcache_page(page);
6431 ClearPageChecked(page);
6432 set_page_dirty(page);
6433 SetPageUptodate(page);
6435 BTRFS_I(inode)->last_trans = root->fs_info->generation;
6436 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
6438 unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS);
6442 return VM_FAULT_LOCKED;
6444 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
6449 static int btrfs_truncate(struct inode *inode)
6451 struct btrfs_root *root = BTRFS_I(inode)->root;
6452 struct btrfs_block_rsv *rsv;
6455 struct btrfs_trans_handle *trans;
6457 u64 mask = root->sectorsize - 1;
6459 ret = btrfs_truncate_page(inode->i_mapping, inode->i_size);
6463 btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
6464 btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
6467 * Yes ladies and gentelment, this is indeed ugly. The fact is we have
6468 * 3 things going on here
6470 * 1) We need to reserve space for our orphan item and the space to
6471 * delete our orphan item. Lord knows we don't want to have a dangling
6472 * orphan item because we didn't reserve space to remove it.
6474 * 2) We need to reserve space to update our inode.
6476 * 3) We need to have something to cache all the space that is going to
6477 * be free'd up by the truncate operation, but also have some slack
6478 * space reserved in case it uses space during the truncate (thank you
6479 * very much snapshotting).
6481 * And we need these to all be seperate. The fact is we can use alot of
6482 * space doing the truncate, and we have no earthly idea how much space
6483 * we will use, so we need the truncate reservation to be seperate so it
6484 * doesn't end up using space reserved for updating the inode or
6485 * removing the orphan item. We also need to be able to stop the
6486 * transaction and start a new one, which means we need to be able to
6487 * update the inode several times, and we have no idea of knowing how
6488 * many times that will be, so we can't just reserve 1 item for the
6489 * entirety of the opration, so that has to be done seperately as well.
6490 * Then there is the orphan item, which does indeed need to be held on
6491 * to for the whole operation, and we need nobody to touch this reserved
6492 * space except the orphan code.
6494 * So that leaves us with
6496 * 1) root->orphan_block_rsv - for the orphan deletion.
6497 * 2) rsv - for the truncate reservation, which we will steal from the
6498 * transaction reservation.
6499 * 3) fs_info->trans_block_rsv - this will have 1 items worth left for
6500 * updating the inode.
6502 rsv = btrfs_alloc_block_rsv(root);
6506 trans = btrfs_start_transaction(root, 4);
6507 if (IS_ERR(trans)) {
6508 err = PTR_ERR(trans);
6513 * Reserve space for the truncate process. Truncate should be adding
6514 * space, but if there are snapshots it may end up using space.
6516 ret = btrfs_truncate_reserve_metadata(trans, root, rsv);
6519 ret = btrfs_orphan_add(trans, inode);
6521 btrfs_end_transaction(trans, root);
6525 nr = trans->blocks_used;
6526 btrfs_end_transaction(trans, root);
6527 btrfs_btree_balance_dirty(root, nr);
6530 * Ok so we've already migrated our bytes over for the truncate, so here
6531 * just reserve the one slot we need for updating the inode.
6533 trans = btrfs_start_transaction(root, 1);
6534 if (IS_ERR(trans)) {
6535 err = PTR_ERR(trans);
6538 trans->block_rsv = rsv;
6541 * setattr is responsible for setting the ordered_data_close flag,
6542 * but that is only tested during the last file release. That
6543 * could happen well after the next commit, leaving a great big
6544 * window where new writes may get lost if someone chooses to write
6545 * to this file after truncating to zero
6547 * The inode doesn't have any dirty data here, and so if we commit
6548 * this is a noop. If someone immediately starts writing to the inode
6549 * it is very likely we'll catch some of their writes in this
6550 * transaction, and the commit will find this file on the ordered
6551 * data list with good things to send down.
6553 * This is a best effort solution, there is still a window where
6554 * using truncate to replace the contents of the file will
6555 * end up with a zero length file after a crash.
6557 if (inode->i_size == 0 && BTRFS_I(inode)->ordered_data_close)
6558 btrfs_add_ordered_operation(trans, root, inode);
6562 trans = btrfs_start_transaction(root, 3);
6563 if (IS_ERR(trans)) {
6564 err = PTR_ERR(trans);
6568 ret = btrfs_truncate_reserve_metadata(trans, root,
6572 trans->block_rsv = rsv;
6575 ret = btrfs_truncate_inode_items(trans, root, inode,
6577 BTRFS_EXTENT_DATA_KEY);
6578 if (ret != -EAGAIN) {
6583 trans->block_rsv = &root->fs_info->trans_block_rsv;
6584 ret = btrfs_update_inode(trans, root, inode);
6590 nr = trans->blocks_used;
6591 btrfs_end_transaction(trans, root);
6593 btrfs_btree_balance_dirty(root, nr);
6596 if (ret == 0 && inode->i_nlink > 0) {
6597 trans->block_rsv = root->orphan_block_rsv;
6598 ret = btrfs_orphan_del(trans, inode);
6601 } else if (ret && inode->i_nlink > 0) {
6603 * Failed to do the truncate, remove us from the in memory
6606 ret = btrfs_orphan_del(NULL, inode);
6609 trans->block_rsv = &root->fs_info->trans_block_rsv;
6610 ret = btrfs_update_inode(trans, root, inode);
6614 nr = trans->blocks_used;
6615 ret = btrfs_end_transaction_throttle(trans, root);
6616 btrfs_btree_balance_dirty(root, nr);
6619 btrfs_free_block_rsv(root, rsv);
6628 * create a new subvolume directory/inode (helper for the ioctl).
6630 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
6631 struct btrfs_root *new_root, u64 new_dirid)
6633 struct inode *inode;
6637 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid,
6638 new_dirid, S_IFDIR | 0700, &index);
6640 return PTR_ERR(inode);
6641 inode->i_op = &btrfs_dir_inode_operations;
6642 inode->i_fop = &btrfs_dir_file_operations;
6645 btrfs_i_size_write(inode, 0);
6647 err = btrfs_update_inode(trans, new_root, inode);
6654 struct inode *btrfs_alloc_inode(struct super_block *sb)
6656 struct btrfs_inode *ei;
6657 struct inode *inode;
6659 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
6664 ei->space_info = NULL;
6668 ei->last_sub_trans = 0;
6669 ei->logged_trans = 0;
6670 ei->delalloc_bytes = 0;
6671 ei->disk_i_size = 0;
6674 ei->index_cnt = (u64)-1;
6675 ei->last_unlink_trans = 0;
6677 spin_lock_init(&ei->lock);
6678 ei->outstanding_extents = 0;
6679 ei->reserved_extents = 0;
6681 ei->ordered_data_close = 0;
6682 ei->orphan_meta_reserved = 0;
6683 ei->dummy_inode = 0;
6685 ei->force_compress = BTRFS_COMPRESS_NONE;
6687 ei->delayed_node = NULL;
6689 inode = &ei->vfs_inode;
6690 extent_map_tree_init(&ei->extent_tree);
6691 extent_io_tree_init(&ei->io_tree, &inode->i_data);
6692 extent_io_tree_init(&ei->io_failure_tree, &inode->i_data);
6693 mutex_init(&ei->log_mutex);
6694 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
6695 INIT_LIST_HEAD(&ei->i_orphan);
6696 INIT_LIST_HEAD(&ei->delalloc_inodes);
6697 INIT_LIST_HEAD(&ei->ordered_operations);
6698 RB_CLEAR_NODE(&ei->rb_node);
6703 static void btrfs_i_callback(struct rcu_head *head)
6705 struct inode *inode = container_of(head, struct inode, i_rcu);
6706 INIT_LIST_HEAD(&inode->i_dentry);
6707 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
6710 void btrfs_destroy_inode(struct inode *inode)
6712 struct btrfs_ordered_extent *ordered;
6713 struct btrfs_root *root = BTRFS_I(inode)->root;
6715 WARN_ON(!list_empty(&inode->i_dentry));
6716 WARN_ON(inode->i_data.nrpages);
6717 WARN_ON(BTRFS_I(inode)->outstanding_extents);
6718 WARN_ON(BTRFS_I(inode)->reserved_extents);
6719 WARN_ON(BTRFS_I(inode)->delalloc_bytes);
6720 WARN_ON(BTRFS_I(inode)->csum_bytes);
6723 * This can happen where we create an inode, but somebody else also
6724 * created the same inode and we need to destroy the one we already
6731 * Make sure we're properly removed from the ordered operation
6735 if (!list_empty(&BTRFS_I(inode)->ordered_operations)) {
6736 spin_lock(&root->fs_info->ordered_extent_lock);
6737 list_del_init(&BTRFS_I(inode)->ordered_operations);
6738 spin_unlock(&root->fs_info->ordered_extent_lock);
6741 spin_lock(&root->orphan_lock);
6742 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
6743 printk(KERN_INFO "BTRFS: inode %llu still on the orphan list\n",
6744 (unsigned long long)btrfs_ino(inode));
6745 list_del_init(&BTRFS_I(inode)->i_orphan);
6747 spin_unlock(&root->orphan_lock);
6750 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
6754 printk(KERN_ERR "btrfs found ordered "
6755 "extent %llu %llu on inode cleanup\n",
6756 (unsigned long long)ordered->file_offset,
6757 (unsigned long long)ordered->len);
6758 btrfs_remove_ordered_extent(inode, ordered);
6759 btrfs_put_ordered_extent(ordered);
6760 btrfs_put_ordered_extent(ordered);
6763 inode_tree_del(inode);
6764 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
6766 btrfs_remove_delayed_node(inode);
6767 call_rcu(&inode->i_rcu, btrfs_i_callback);
6770 int btrfs_drop_inode(struct inode *inode)
6772 struct btrfs_root *root = BTRFS_I(inode)->root;
6774 if (btrfs_root_refs(&root->root_item) == 0 &&
6775 !btrfs_is_free_space_inode(root, inode))
6778 return generic_drop_inode(inode);
6781 static void init_once(void *foo)
6783 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
6785 inode_init_once(&ei->vfs_inode);
6788 void btrfs_destroy_cachep(void)
6790 if (btrfs_inode_cachep)
6791 kmem_cache_destroy(btrfs_inode_cachep);
6792 if (btrfs_trans_handle_cachep)
6793 kmem_cache_destroy(btrfs_trans_handle_cachep);
6794 if (btrfs_transaction_cachep)
6795 kmem_cache_destroy(btrfs_transaction_cachep);
6796 if (btrfs_path_cachep)
6797 kmem_cache_destroy(btrfs_path_cachep);
6798 if (btrfs_free_space_cachep)
6799 kmem_cache_destroy(btrfs_free_space_cachep);
6802 int btrfs_init_cachep(void)
6804 btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache",
6805 sizeof(struct btrfs_inode), 0,
6806 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once);
6807 if (!btrfs_inode_cachep)
6810 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache",
6811 sizeof(struct btrfs_trans_handle), 0,
6812 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6813 if (!btrfs_trans_handle_cachep)
6816 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache",
6817 sizeof(struct btrfs_transaction), 0,
6818 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6819 if (!btrfs_transaction_cachep)
6822 btrfs_path_cachep = kmem_cache_create("btrfs_path_cache",
6823 sizeof(struct btrfs_path), 0,
6824 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6825 if (!btrfs_path_cachep)
6828 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space_cache",
6829 sizeof(struct btrfs_free_space), 0,
6830 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6831 if (!btrfs_free_space_cachep)
6836 btrfs_destroy_cachep();
6840 static int btrfs_getattr(struct vfsmount *mnt,
6841 struct dentry *dentry, struct kstat *stat)
6843 struct inode *inode = dentry->d_inode;
6844 generic_fillattr(inode, stat);
6845 stat->dev = BTRFS_I(inode)->root->anon_dev;
6846 stat->blksize = PAGE_CACHE_SIZE;
6847 stat->blocks = (inode_get_bytes(inode) +
6848 BTRFS_I(inode)->delalloc_bytes) >> 9;
6853 * If a file is moved, it will inherit the cow and compression flags of the new
6856 static void fixup_inode_flags(struct inode *dir, struct inode *inode)
6858 struct btrfs_inode *b_dir = BTRFS_I(dir);
6859 struct btrfs_inode *b_inode = BTRFS_I(inode);
6861 if (b_dir->flags & BTRFS_INODE_NODATACOW)
6862 b_inode->flags |= BTRFS_INODE_NODATACOW;
6864 b_inode->flags &= ~BTRFS_INODE_NODATACOW;
6866 if (b_dir->flags & BTRFS_INODE_COMPRESS)
6867 b_inode->flags |= BTRFS_INODE_COMPRESS;
6869 b_inode->flags &= ~BTRFS_INODE_COMPRESS;
6872 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
6873 struct inode *new_dir, struct dentry *new_dentry)
6875 struct btrfs_trans_handle *trans;
6876 struct btrfs_root *root = BTRFS_I(old_dir)->root;
6877 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
6878 struct inode *new_inode = new_dentry->d_inode;
6879 struct inode *old_inode = old_dentry->d_inode;
6880 struct timespec ctime = CURRENT_TIME;
6884 u64 old_ino = btrfs_ino(old_inode);
6886 if (btrfs_ino(new_dir) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
6889 /* we only allow rename subvolume link between subvolumes */
6890 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
6893 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
6894 (new_inode && btrfs_ino(new_inode) == BTRFS_FIRST_FREE_OBJECTID))
6897 if (S_ISDIR(old_inode->i_mode) && new_inode &&
6898 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
6901 * we're using rename to replace one file with another.
6902 * and the replacement file is large. Start IO on it now so
6903 * we don't add too much work to the end of the transaction
6905 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size &&
6906 old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
6907 filemap_flush(old_inode->i_mapping);
6909 /* close the racy window with snapshot create/destroy ioctl */
6910 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
6911 down_read(&root->fs_info->subvol_sem);
6913 * We want to reserve the absolute worst case amount of items. So if
6914 * both inodes are subvols and we need to unlink them then that would
6915 * require 4 item modifications, but if they are both normal inodes it
6916 * would require 5 item modifications, so we'll assume their normal
6917 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
6918 * should cover the worst case number of items we'll modify.
6920 trans = btrfs_start_transaction(root, 20);
6921 if (IS_ERR(trans)) {
6922 ret = PTR_ERR(trans);
6927 btrfs_record_root_in_trans(trans, dest);
6929 ret = btrfs_set_inode_index(new_dir, &index);
6933 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
6934 /* force full log commit if subvolume involved. */
6935 root->fs_info->last_trans_log_full_commit = trans->transid;
6937 ret = btrfs_insert_inode_ref(trans, dest,
6938 new_dentry->d_name.name,
6939 new_dentry->d_name.len,
6941 btrfs_ino(new_dir), index);
6945 * this is an ugly little race, but the rename is required
6946 * to make sure that if we crash, the inode is either at the
6947 * old name or the new one. pinning the log transaction lets
6948 * us make sure we don't allow a log commit to come in after
6949 * we unlink the name but before we add the new name back in.
6951 btrfs_pin_log_trans(root);
6954 * make sure the inode gets flushed if it is replacing
6957 if (new_inode && new_inode->i_size && S_ISREG(old_inode->i_mode))
6958 btrfs_add_ordered_operation(trans, root, old_inode);
6960 old_dir->i_ctime = old_dir->i_mtime = ctime;
6961 new_dir->i_ctime = new_dir->i_mtime = ctime;
6962 old_inode->i_ctime = ctime;
6964 if (old_dentry->d_parent != new_dentry->d_parent)
6965 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1);
6967 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
6968 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
6969 ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid,
6970 old_dentry->d_name.name,
6971 old_dentry->d_name.len);
6973 ret = __btrfs_unlink_inode(trans, root, old_dir,
6974 old_dentry->d_inode,
6975 old_dentry->d_name.name,
6976 old_dentry->d_name.len);
6978 ret = btrfs_update_inode(trans, root, old_inode);
6983 new_inode->i_ctime = CURRENT_TIME;
6984 if (unlikely(btrfs_ino(new_inode) ==
6985 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
6986 root_objectid = BTRFS_I(new_inode)->location.objectid;
6987 ret = btrfs_unlink_subvol(trans, dest, new_dir,
6989 new_dentry->d_name.name,
6990 new_dentry->d_name.len);
6991 BUG_ON(new_inode->i_nlink == 0);
6993 ret = btrfs_unlink_inode(trans, dest, new_dir,
6994 new_dentry->d_inode,
6995 new_dentry->d_name.name,
6996 new_dentry->d_name.len);
6999 if (new_inode->i_nlink == 0) {
7000 ret = btrfs_orphan_add(trans, new_dentry->d_inode);
7005 fixup_inode_flags(new_dir, old_inode);
7007 ret = btrfs_add_link(trans, new_dir, old_inode,
7008 new_dentry->d_name.name,
7009 new_dentry->d_name.len, 0, index);
7012 if (old_ino != BTRFS_FIRST_FREE_OBJECTID) {
7013 struct dentry *parent = new_dentry->d_parent;
7014 btrfs_log_new_name(trans, old_inode, old_dir, parent);
7015 btrfs_end_log_trans(root);
7018 btrfs_end_transaction_throttle(trans, root);
7020 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
7021 up_read(&root->fs_info->subvol_sem);
7027 * some fairly slow code that needs optimization. This walks the list
7028 * of all the inodes with pending delalloc and forces them to disk.
7030 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
7032 struct list_head *head = &root->fs_info->delalloc_inodes;
7033 struct btrfs_inode *binode;
7034 struct inode *inode;
7036 if (root->fs_info->sb->s_flags & MS_RDONLY)
7039 spin_lock(&root->fs_info->delalloc_lock);
7040 while (!list_empty(head)) {
7041 binode = list_entry(head->next, struct btrfs_inode,
7043 inode = igrab(&binode->vfs_inode);
7045 list_del_init(&binode->delalloc_inodes);
7046 spin_unlock(&root->fs_info->delalloc_lock);
7048 filemap_flush(inode->i_mapping);
7050 btrfs_add_delayed_iput(inode);
7055 spin_lock(&root->fs_info->delalloc_lock);
7057 spin_unlock(&root->fs_info->delalloc_lock);
7059 /* the filemap_flush will queue IO into the worker threads, but
7060 * we have to make sure the IO is actually started and that
7061 * ordered extents get created before we return
7063 atomic_inc(&root->fs_info->async_submit_draining);
7064 while (atomic_read(&root->fs_info->nr_async_submits) ||
7065 atomic_read(&root->fs_info->async_delalloc_pages)) {
7066 wait_event(root->fs_info->async_submit_wait,
7067 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
7068 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
7070 atomic_dec(&root->fs_info->async_submit_draining);
7074 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
7075 const char *symname)
7077 struct btrfs_trans_handle *trans;
7078 struct btrfs_root *root = BTRFS_I(dir)->root;
7079 struct btrfs_path *path;
7080 struct btrfs_key key;
7081 struct inode *inode = NULL;
7089 struct btrfs_file_extent_item *ei;
7090 struct extent_buffer *leaf;
7091 unsigned long nr = 0;
7093 name_len = strlen(symname) + 1;
7094 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
7095 return -ENAMETOOLONG;
7098 * 2 items for inode item and ref
7099 * 2 items for dir items
7100 * 1 item for xattr if selinux is on
7102 trans = btrfs_start_transaction(root, 5);
7104 return PTR_ERR(trans);
7106 err = btrfs_find_free_ino(root, &objectid);
7110 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
7111 dentry->d_name.len, btrfs_ino(dir), objectid,
7112 S_IFLNK|S_IRWXUGO, &index);
7113 if (IS_ERR(inode)) {
7114 err = PTR_ERR(inode);
7118 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
7124 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
7128 inode->i_mapping->a_ops = &btrfs_aops;
7129 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
7130 inode->i_fop = &btrfs_file_operations;
7131 inode->i_op = &btrfs_file_inode_operations;
7132 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
7137 path = btrfs_alloc_path();
7143 key.objectid = btrfs_ino(inode);
7145 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
7146 datasize = btrfs_file_extent_calc_inline_size(name_len);
7147 err = btrfs_insert_empty_item(trans, root, path, &key,
7151 btrfs_free_path(path);
7154 leaf = path->nodes[0];
7155 ei = btrfs_item_ptr(leaf, path->slots[0],
7156 struct btrfs_file_extent_item);
7157 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
7158 btrfs_set_file_extent_type(leaf, ei,
7159 BTRFS_FILE_EXTENT_INLINE);
7160 btrfs_set_file_extent_encryption(leaf, ei, 0);
7161 btrfs_set_file_extent_compression(leaf, ei, 0);
7162 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
7163 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
7165 ptr = btrfs_file_extent_inline_start(ei);
7166 write_extent_buffer(leaf, symname, ptr, name_len);
7167 btrfs_mark_buffer_dirty(leaf);
7168 btrfs_free_path(path);
7170 inode->i_op = &btrfs_symlink_inode_operations;
7171 inode->i_mapping->a_ops = &btrfs_symlink_aops;
7172 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
7173 inode_set_bytes(inode, name_len);
7174 btrfs_i_size_write(inode, name_len - 1);
7175 err = btrfs_update_inode(trans, root, inode);
7180 nr = trans->blocks_used;
7181 btrfs_end_transaction_throttle(trans, root);
7183 inode_dec_link_count(inode);
7186 btrfs_btree_balance_dirty(root, nr);
7190 static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
7191 u64 start, u64 num_bytes, u64 min_size,
7192 loff_t actual_len, u64 *alloc_hint,
7193 struct btrfs_trans_handle *trans)
7195 struct btrfs_root *root = BTRFS_I(inode)->root;
7196 struct btrfs_key ins;
7197 u64 cur_offset = start;
7200 bool own_trans = true;
7204 while (num_bytes > 0) {
7206 trans = btrfs_start_transaction(root, 3);
7207 if (IS_ERR(trans)) {
7208 ret = PTR_ERR(trans);
7213 ret = btrfs_reserve_extent(trans, root, num_bytes, min_size,
7214 0, *alloc_hint, (u64)-1, &ins, 1);
7217 btrfs_end_transaction(trans, root);
7221 ret = insert_reserved_file_extent(trans, inode,
7222 cur_offset, ins.objectid,
7223 ins.offset, ins.offset,
7224 ins.offset, 0, 0, 0,
7225 BTRFS_FILE_EXTENT_PREALLOC);
7227 btrfs_drop_extent_cache(inode, cur_offset,
7228 cur_offset + ins.offset -1, 0);
7230 num_bytes -= ins.offset;
7231 cur_offset += ins.offset;
7232 *alloc_hint = ins.objectid + ins.offset;
7234 inode->i_ctime = CURRENT_TIME;
7235 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
7236 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
7237 (actual_len > inode->i_size) &&
7238 (cur_offset > inode->i_size)) {
7239 if (cur_offset > actual_len)
7240 i_size = actual_len;
7242 i_size = cur_offset;
7243 i_size_write(inode, i_size);
7244 btrfs_ordered_update_i_size(inode, i_size, NULL);
7247 ret = btrfs_update_inode(trans, root, inode);
7251 btrfs_end_transaction(trans, root);
7256 int btrfs_prealloc_file_range(struct inode *inode, int mode,
7257 u64 start, u64 num_bytes, u64 min_size,
7258 loff_t actual_len, u64 *alloc_hint)
7260 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
7261 min_size, actual_len, alloc_hint,
7265 int btrfs_prealloc_file_range_trans(struct inode *inode,
7266 struct btrfs_trans_handle *trans, int mode,
7267 u64 start, u64 num_bytes, u64 min_size,
7268 loff_t actual_len, u64 *alloc_hint)
7270 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
7271 min_size, actual_len, alloc_hint, trans);
7274 static int btrfs_set_page_dirty(struct page *page)
7276 return __set_page_dirty_nobuffers(page);
7279 static int btrfs_permission(struct inode *inode, int mask)
7281 struct btrfs_root *root = BTRFS_I(inode)->root;
7282 umode_t mode = inode->i_mode;
7284 if (mask & MAY_WRITE &&
7285 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) {
7286 if (btrfs_root_readonly(root))
7288 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
7291 return generic_permission(inode, mask);
7294 static const struct inode_operations btrfs_dir_inode_operations = {
7295 .getattr = btrfs_getattr,
7296 .lookup = btrfs_lookup,
7297 .create = btrfs_create,
7298 .unlink = btrfs_unlink,
7300 .mkdir = btrfs_mkdir,
7301 .rmdir = btrfs_rmdir,
7302 .rename = btrfs_rename,
7303 .symlink = btrfs_symlink,
7304 .setattr = btrfs_setattr,
7305 .mknod = btrfs_mknod,
7306 .setxattr = btrfs_setxattr,
7307 .getxattr = btrfs_getxattr,
7308 .listxattr = btrfs_listxattr,
7309 .removexattr = btrfs_removexattr,
7310 .permission = btrfs_permission,
7311 .get_acl = btrfs_get_acl,
7313 static const struct inode_operations btrfs_dir_ro_inode_operations = {
7314 .lookup = btrfs_lookup,
7315 .permission = btrfs_permission,
7316 .get_acl = btrfs_get_acl,
7319 static const struct file_operations btrfs_dir_file_operations = {
7320 .llseek = generic_file_llseek,
7321 .read = generic_read_dir,
7322 .readdir = btrfs_real_readdir,
7323 .unlocked_ioctl = btrfs_ioctl,
7324 #ifdef CONFIG_COMPAT
7325 .compat_ioctl = btrfs_ioctl,
7327 .release = btrfs_release_file,
7328 .fsync = btrfs_sync_file,
7331 static struct extent_io_ops btrfs_extent_io_ops = {
7332 .fill_delalloc = run_delalloc_range,
7333 .submit_bio_hook = btrfs_submit_bio_hook,
7334 .merge_bio_hook = btrfs_merge_bio_hook,
7335 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
7336 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
7337 .writepage_start_hook = btrfs_writepage_start_hook,
7338 .readpage_io_failed_hook = btrfs_io_failed_hook,
7339 .set_bit_hook = btrfs_set_bit_hook,
7340 .clear_bit_hook = btrfs_clear_bit_hook,
7341 .merge_extent_hook = btrfs_merge_extent_hook,
7342 .split_extent_hook = btrfs_split_extent_hook,
7346 * btrfs doesn't support the bmap operation because swapfiles
7347 * use bmap to make a mapping of extents in the file. They assume
7348 * these extents won't change over the life of the file and they
7349 * use the bmap result to do IO directly to the drive.
7351 * the btrfs bmap call would return logical addresses that aren't
7352 * suitable for IO and they also will change frequently as COW
7353 * operations happen. So, swapfile + btrfs == corruption.
7355 * For now we're avoiding this by dropping bmap.
7357 static const struct address_space_operations btrfs_aops = {
7358 .readpage = btrfs_readpage,
7359 .writepage = btrfs_writepage,
7360 .writepages = btrfs_writepages,
7361 .readpages = btrfs_readpages,
7362 .direct_IO = btrfs_direct_IO,
7363 .invalidatepage = btrfs_invalidatepage,
7364 .releasepage = btrfs_releasepage,
7365 .set_page_dirty = btrfs_set_page_dirty,
7366 .error_remove_page = generic_error_remove_page,
7369 static const struct address_space_operations btrfs_symlink_aops = {
7370 .readpage = btrfs_readpage,
7371 .writepage = btrfs_writepage,
7372 .invalidatepage = btrfs_invalidatepage,
7373 .releasepage = btrfs_releasepage,
7376 static const struct inode_operations btrfs_file_inode_operations = {
7377 .getattr = btrfs_getattr,
7378 .setattr = btrfs_setattr,
7379 .setxattr = btrfs_setxattr,
7380 .getxattr = btrfs_getxattr,
7381 .listxattr = btrfs_listxattr,
7382 .removexattr = btrfs_removexattr,
7383 .permission = btrfs_permission,
7384 .fiemap = btrfs_fiemap,
7385 .get_acl = btrfs_get_acl,
7387 static const struct inode_operations btrfs_special_inode_operations = {
7388 .getattr = btrfs_getattr,
7389 .setattr = btrfs_setattr,
7390 .permission = btrfs_permission,
7391 .setxattr = btrfs_setxattr,
7392 .getxattr = btrfs_getxattr,
7393 .listxattr = btrfs_listxattr,
7394 .removexattr = btrfs_removexattr,
7395 .get_acl = btrfs_get_acl,
7397 static const struct inode_operations btrfs_symlink_inode_operations = {
7398 .readlink = generic_readlink,
7399 .follow_link = page_follow_link_light,
7400 .put_link = page_put_link,
7401 .getattr = btrfs_getattr,
7402 .permission = btrfs_permission,
7403 .setxattr = btrfs_setxattr,
7404 .getxattr = btrfs_getxattr,
7405 .listxattr = btrfs_listxattr,
7406 .removexattr = btrfs_removexattr,
7407 .get_acl = btrfs_get_acl,
7410 const struct dentry_operations btrfs_dentry_operations = {
7411 .d_delete = btrfs_dentry_delete,
7412 .d_release = btrfs_dentry_release,