2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #include <linux/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.h>
24 #include <linux/pagemap.h>
25 #include <linux/highmem.h>
26 #include <linux/time.h>
27 #include <linux/init.h>
28 #include <linux/string.h>
29 #include <linux/backing-dev.h>
30 #include <linux/mpage.h>
31 #include <linux/swap.h>
32 #include <linux/writeback.h>
33 #include <linux/statfs.h>
34 #include <linux/compat.h>
35 #include <linux/bit_spinlock.h>
36 #include <linux/xattr.h>
37 #include <linux/posix_acl.h>
38 #include <linux/falloc.h>
39 #include <linux/slab.h>
40 #include <linux/ratelimit.h>
41 #include <linux/mount.h>
45 #include "transaction.h"
46 #include "btrfs_inode.h"
48 #include "print-tree.h"
49 #include "ordered-data.h"
53 #include "compression.h"
55 #include "free-space-cache.h"
56 #include "inode-map.h"
58 struct btrfs_iget_args {
59 struct btrfs_key *location;
60 struct btrfs_root *root;
63 static const struct inode_operations btrfs_dir_inode_operations;
64 static const struct inode_operations btrfs_symlink_inode_operations;
65 static const struct inode_operations btrfs_dir_ro_inode_operations;
66 static const struct inode_operations btrfs_special_inode_operations;
67 static const struct inode_operations btrfs_file_inode_operations;
68 static const struct address_space_operations btrfs_aops;
69 static const struct address_space_operations btrfs_symlink_aops;
70 static const struct file_operations btrfs_dir_file_operations;
71 static struct extent_io_ops btrfs_extent_io_ops;
73 static struct kmem_cache *btrfs_inode_cachep;
74 struct kmem_cache *btrfs_trans_handle_cachep;
75 struct kmem_cache *btrfs_transaction_cachep;
76 struct kmem_cache *btrfs_path_cachep;
77 struct kmem_cache *btrfs_free_space_cachep;
80 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
81 [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
82 [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
83 [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
84 [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
85 [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
86 [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
87 [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
90 static int btrfs_setsize(struct inode *inode, loff_t newsize);
91 static int btrfs_truncate(struct inode *inode);
92 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end);
93 static noinline int cow_file_range(struct inode *inode,
94 struct page *locked_page,
95 u64 start, u64 end, int *page_started,
96 unsigned long *nr_written, int unlock);
97 static noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
98 struct btrfs_root *root, struct inode *inode);
100 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
101 struct inode *inode, struct inode *dir,
102 const struct qstr *qstr)
106 err = btrfs_init_acl(trans, inode, dir);
108 err = btrfs_xattr_security_init(trans, inode, dir, qstr);
113 * this does all the hard work for inserting an inline extent into
114 * the btree. The caller should have done a btrfs_drop_extents so that
115 * no overlapping inline items exist in the btree
117 static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
118 struct btrfs_root *root, struct inode *inode,
119 u64 start, size_t size, size_t compressed_size,
121 struct page **compressed_pages)
123 struct btrfs_key key;
124 struct btrfs_path *path;
125 struct extent_buffer *leaf;
126 struct page *page = NULL;
129 struct btrfs_file_extent_item *ei;
132 size_t cur_size = size;
134 unsigned long offset;
136 if (compressed_size && compressed_pages)
137 cur_size = compressed_size;
139 path = btrfs_alloc_path();
143 path->leave_spinning = 1;
145 key.objectid = btrfs_ino(inode);
147 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
148 datasize = btrfs_file_extent_calc_inline_size(cur_size);
150 inode_add_bytes(inode, size);
151 ret = btrfs_insert_empty_item(trans, root, path, &key,
158 leaf = path->nodes[0];
159 ei = btrfs_item_ptr(leaf, path->slots[0],
160 struct btrfs_file_extent_item);
161 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
162 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
163 btrfs_set_file_extent_encryption(leaf, ei, 0);
164 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
165 btrfs_set_file_extent_ram_bytes(leaf, ei, size);
166 ptr = btrfs_file_extent_inline_start(ei);
168 if (compress_type != BTRFS_COMPRESS_NONE) {
171 while (compressed_size > 0) {
172 cpage = compressed_pages[i];
173 cur_size = min_t(unsigned long, compressed_size,
176 kaddr = kmap_atomic(cpage, KM_USER0);
177 write_extent_buffer(leaf, kaddr, ptr, cur_size);
178 kunmap_atomic(kaddr, KM_USER0);
182 compressed_size -= cur_size;
184 btrfs_set_file_extent_compression(leaf, ei,
187 page = find_get_page(inode->i_mapping,
188 start >> PAGE_CACHE_SHIFT);
189 btrfs_set_file_extent_compression(leaf, ei, 0);
190 kaddr = kmap_atomic(page, KM_USER0);
191 offset = start & (PAGE_CACHE_SIZE - 1);
192 write_extent_buffer(leaf, kaddr + offset, ptr, size);
193 kunmap_atomic(kaddr, KM_USER0);
194 page_cache_release(page);
196 btrfs_mark_buffer_dirty(leaf);
197 btrfs_free_path(path);
200 * we're an inline extent, so nobody can
201 * extend the file past i_size without locking
202 * a page we already have locked.
204 * We must do any isize and inode updates
205 * before we unlock the pages. Otherwise we
206 * could end up racing with unlink.
208 BTRFS_I(inode)->disk_i_size = inode->i_size;
209 btrfs_update_inode(trans, root, inode);
213 btrfs_free_path(path);
219 * conditionally insert an inline extent into the file. This
220 * does the checks required to make sure the data is small enough
221 * to fit as an inline extent.
223 static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans,
224 struct btrfs_root *root,
225 struct inode *inode, u64 start, u64 end,
226 size_t compressed_size, int compress_type,
227 struct page **compressed_pages)
229 u64 isize = i_size_read(inode);
230 u64 actual_end = min(end + 1, isize);
231 u64 inline_len = actual_end - start;
232 u64 aligned_end = (end + root->sectorsize - 1) &
233 ~((u64)root->sectorsize - 1);
235 u64 data_len = inline_len;
239 data_len = compressed_size;
242 actual_end >= PAGE_CACHE_SIZE ||
243 data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) ||
245 (actual_end & (root->sectorsize - 1)) == 0) ||
247 data_len > root->fs_info->max_inline) {
251 ret = btrfs_drop_extents(trans, inode, start, aligned_end,
255 if (isize > actual_end)
256 inline_len = min_t(u64, isize, actual_end);
257 ret = insert_inline_extent(trans, root, inode, start,
258 inline_len, compressed_size,
259 compress_type, compressed_pages);
261 btrfs_delalloc_release_metadata(inode, end + 1 - start);
262 btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0);
266 struct async_extent {
271 unsigned long nr_pages;
273 struct list_head list;
278 struct btrfs_root *root;
279 struct page *locked_page;
282 struct list_head extents;
283 struct btrfs_work work;
286 static noinline int add_async_extent(struct async_cow *cow,
287 u64 start, u64 ram_size,
290 unsigned long nr_pages,
293 struct async_extent *async_extent;
295 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
296 BUG_ON(!async_extent);
297 async_extent->start = start;
298 async_extent->ram_size = ram_size;
299 async_extent->compressed_size = compressed_size;
300 async_extent->pages = pages;
301 async_extent->nr_pages = nr_pages;
302 async_extent->compress_type = compress_type;
303 list_add_tail(&async_extent->list, &cow->extents);
308 * we create compressed extents in two phases. The first
309 * phase compresses a range of pages that have already been
310 * locked (both pages and state bits are locked).
312 * This is done inside an ordered work queue, and the compression
313 * is spread across many cpus. The actual IO submission is step
314 * two, and the ordered work queue takes care of making sure that
315 * happens in the same order things were put onto the queue by
316 * writepages and friends.
318 * If this code finds it can't get good compression, it puts an
319 * entry onto the work queue to write the uncompressed bytes. This
320 * makes sure that both compressed inodes and uncompressed inodes
321 * are written in the same order that pdflush sent them down.
323 static noinline int compress_file_range(struct inode *inode,
324 struct page *locked_page,
326 struct async_cow *async_cow,
329 struct btrfs_root *root = BTRFS_I(inode)->root;
330 struct btrfs_trans_handle *trans;
332 u64 blocksize = root->sectorsize;
334 u64 isize = i_size_read(inode);
336 struct page **pages = NULL;
337 unsigned long nr_pages;
338 unsigned long nr_pages_ret = 0;
339 unsigned long total_compressed = 0;
340 unsigned long total_in = 0;
341 unsigned long max_compressed = 128 * 1024;
342 unsigned long max_uncompressed = 128 * 1024;
345 int compress_type = root->fs_info->compress_type;
348 /* if this is a small write inside eof, kick off a defragbot */
349 if (end <= BTRFS_I(inode)->disk_i_size && (end - start + 1) < 16 * 1024)
350 btrfs_add_inode_defrag(NULL, inode);
352 actual_end = min_t(u64, isize, end + 1);
355 nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1;
356 nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_SIZE);
359 * we don't want to send crud past the end of i_size through
360 * compression, that's just a waste of CPU time. So, if the
361 * end of the file is before the start of our current
362 * requested range of bytes, we bail out to the uncompressed
363 * cleanup code that can deal with all of this.
365 * It isn't really the fastest way to fix things, but this is a
366 * very uncommon corner.
368 if (actual_end <= start)
369 goto cleanup_and_bail_uncompressed;
371 total_compressed = actual_end - start;
373 /* we want to make sure that amount of ram required to uncompress
374 * an extent is reasonable, so we limit the total size in ram
375 * of a compressed extent to 128k. This is a crucial number
376 * because it also controls how easily we can spread reads across
377 * cpus for decompression.
379 * We also want to make sure the amount of IO required to do
380 * a random read is reasonably small, so we limit the size of
381 * a compressed extent to 128k.
383 total_compressed = min(total_compressed, max_uncompressed);
384 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
385 num_bytes = max(blocksize, num_bytes);
390 * we do compression for mount -o compress and when the
391 * inode has not been flagged as nocompress. This flag can
392 * change at any time if we discover bad compression ratios.
394 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) &&
395 (btrfs_test_opt(root, COMPRESS) ||
396 (BTRFS_I(inode)->force_compress) ||
397 (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))) {
399 pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
401 /* just bail out to the uncompressed code */
405 if (BTRFS_I(inode)->force_compress)
406 compress_type = BTRFS_I(inode)->force_compress;
409 * we need to call clear_page_dirty_for_io on each
410 * page in the range. Otherwise applications with the file
411 * mmap'd can wander in and change the page contents while
412 * we are compressing them.
414 * If the compression fails for any reason, we set the pages
415 * dirty again later on.
417 extent_range_clear_dirty_for_io(inode, start, end);
419 ret = btrfs_compress_pages(compress_type,
420 inode->i_mapping, start,
421 total_compressed, pages,
422 nr_pages, &nr_pages_ret,
428 unsigned long offset = total_compressed &
429 (PAGE_CACHE_SIZE - 1);
430 struct page *page = pages[nr_pages_ret - 1];
433 /* zero the tail end of the last page, we might be
434 * sending it down to disk
437 kaddr = kmap_atomic(page, KM_USER0);
438 memset(kaddr + offset, 0,
439 PAGE_CACHE_SIZE - offset);
440 kunmap_atomic(kaddr, KM_USER0);
447 trans = btrfs_join_transaction(root);
448 BUG_ON(IS_ERR(trans));
449 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
451 /* lets try to make an inline extent */
452 if (ret || total_in < (actual_end - start)) {
453 /* we didn't compress the entire range, try
454 * to make an uncompressed inline extent.
456 ret = cow_file_range_inline(trans, root, inode,
457 start, end, 0, 0, NULL);
459 /* try making a compressed inline extent */
460 ret = cow_file_range_inline(trans, root, inode,
463 compress_type, pages);
467 * inline extent creation worked, we don't need
468 * to create any more async work items. Unlock
469 * and free up our temp pages.
471 extent_clear_unlock_delalloc(inode,
472 &BTRFS_I(inode)->io_tree,
474 EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
475 EXTENT_CLEAR_DELALLOC |
476 EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK);
478 btrfs_end_transaction(trans, root);
481 btrfs_end_transaction(trans, root);
486 * we aren't doing an inline extent round the compressed size
487 * up to a block size boundary so the allocator does sane
490 total_compressed = (total_compressed + blocksize - 1) &
494 * one last check to make sure the compression is really a
495 * win, compare the page count read with the blocks on disk
497 total_in = (total_in + PAGE_CACHE_SIZE - 1) &
498 ~(PAGE_CACHE_SIZE - 1);
499 if (total_compressed >= total_in) {
502 num_bytes = total_in;
505 if (!will_compress && pages) {
507 * the compression code ran but failed to make things smaller,
508 * free any pages it allocated and our page pointer array
510 for (i = 0; i < nr_pages_ret; i++) {
511 WARN_ON(pages[i]->mapping);
512 page_cache_release(pages[i]);
516 total_compressed = 0;
519 /* flag the file so we don't compress in the future */
520 if (!btrfs_test_opt(root, FORCE_COMPRESS) &&
521 !(BTRFS_I(inode)->force_compress)) {
522 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
528 /* the async work queues will take care of doing actual
529 * allocation on disk for these compressed pages,
530 * and will submit them to the elevator.
532 add_async_extent(async_cow, start, num_bytes,
533 total_compressed, pages, nr_pages_ret,
536 if (start + num_bytes < end) {
543 cleanup_and_bail_uncompressed:
545 * No compression, but we still need to write the pages in
546 * the file we've been given so far. redirty the locked
547 * page if it corresponds to our extent and set things up
548 * for the async work queue to run cow_file_range to do
549 * the normal delalloc dance
551 if (page_offset(locked_page) >= start &&
552 page_offset(locked_page) <= end) {
553 __set_page_dirty_nobuffers(locked_page);
554 /* unlocked later on in the async handlers */
557 extent_range_redirty_for_io(inode, start, end);
558 add_async_extent(async_cow, start, end - start + 1,
559 0, NULL, 0, BTRFS_COMPRESS_NONE);
567 for (i = 0; i < nr_pages_ret; i++) {
568 WARN_ON(pages[i]->mapping);
569 page_cache_release(pages[i]);
577 * phase two of compressed writeback. This is the ordered portion
578 * of the code, which only gets called in the order the work was
579 * queued. We walk all the async extents created by compress_file_range
580 * and send them down to the disk.
582 static noinline int submit_compressed_extents(struct inode *inode,
583 struct async_cow *async_cow)
585 struct async_extent *async_extent;
587 struct btrfs_trans_handle *trans;
588 struct btrfs_key ins;
589 struct extent_map *em;
590 struct btrfs_root *root = BTRFS_I(inode)->root;
591 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
592 struct extent_io_tree *io_tree;
595 if (list_empty(&async_cow->extents))
599 while (!list_empty(&async_cow->extents)) {
600 async_extent = list_entry(async_cow->extents.next,
601 struct async_extent, list);
602 list_del(&async_extent->list);
604 io_tree = &BTRFS_I(inode)->io_tree;
607 /* did the compression code fall back to uncompressed IO? */
608 if (!async_extent->pages) {
609 int page_started = 0;
610 unsigned long nr_written = 0;
612 lock_extent(io_tree, async_extent->start,
613 async_extent->start +
614 async_extent->ram_size - 1, GFP_NOFS);
616 /* allocate blocks */
617 ret = cow_file_range(inode, async_cow->locked_page,
619 async_extent->start +
620 async_extent->ram_size - 1,
621 &page_started, &nr_written, 0);
624 * if page_started, cow_file_range inserted an
625 * inline extent and took care of all the unlocking
626 * and IO for us. Otherwise, we need to submit
627 * all those pages down to the drive.
629 if (!page_started && !ret)
630 extent_write_locked_range(io_tree,
631 inode, async_extent->start,
632 async_extent->start +
633 async_extent->ram_size - 1,
641 lock_extent(io_tree, async_extent->start,
642 async_extent->start + async_extent->ram_size - 1,
645 trans = btrfs_join_transaction(root);
646 BUG_ON(IS_ERR(trans));
647 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
648 ret = btrfs_reserve_extent(trans, root,
649 async_extent->compressed_size,
650 async_extent->compressed_size,
653 btrfs_end_transaction(trans, root);
657 for (i = 0; i < async_extent->nr_pages; i++) {
658 WARN_ON(async_extent->pages[i]->mapping);
659 page_cache_release(async_extent->pages[i]);
661 kfree(async_extent->pages);
662 async_extent->nr_pages = 0;
663 async_extent->pages = NULL;
664 unlock_extent(io_tree, async_extent->start,
665 async_extent->start +
666 async_extent->ram_size - 1, GFP_NOFS);
671 * here we're doing allocation and writeback of the
674 btrfs_drop_extent_cache(inode, async_extent->start,
675 async_extent->start +
676 async_extent->ram_size - 1, 0);
678 em = alloc_extent_map();
680 em->start = async_extent->start;
681 em->len = async_extent->ram_size;
682 em->orig_start = em->start;
684 em->block_start = ins.objectid;
685 em->block_len = ins.offset;
686 em->bdev = root->fs_info->fs_devices->latest_bdev;
687 em->compress_type = async_extent->compress_type;
688 set_bit(EXTENT_FLAG_PINNED, &em->flags);
689 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
692 write_lock(&em_tree->lock);
693 ret = add_extent_mapping(em_tree, em);
694 write_unlock(&em_tree->lock);
695 if (ret != -EEXIST) {
699 btrfs_drop_extent_cache(inode, async_extent->start,
700 async_extent->start +
701 async_extent->ram_size - 1, 0);
704 ret = btrfs_add_ordered_extent_compress(inode,
707 async_extent->ram_size,
709 BTRFS_ORDERED_COMPRESSED,
710 async_extent->compress_type);
714 * clear dirty, set writeback and unlock the pages.
716 extent_clear_unlock_delalloc(inode,
717 &BTRFS_I(inode)->io_tree,
719 async_extent->start +
720 async_extent->ram_size - 1,
721 NULL, EXTENT_CLEAR_UNLOCK_PAGE |
722 EXTENT_CLEAR_UNLOCK |
723 EXTENT_CLEAR_DELALLOC |
724 EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK);
726 ret = btrfs_submit_compressed_write(inode,
728 async_extent->ram_size,
730 ins.offset, async_extent->pages,
731 async_extent->nr_pages);
734 alloc_hint = ins.objectid + ins.offset;
742 static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
745 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
746 struct extent_map *em;
749 read_lock(&em_tree->lock);
750 em = search_extent_mapping(em_tree, start, num_bytes);
753 * if block start isn't an actual block number then find the
754 * first block in this inode and use that as a hint. If that
755 * block is also bogus then just don't worry about it.
757 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
759 em = search_extent_mapping(em_tree, 0, 0);
760 if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
761 alloc_hint = em->block_start;
765 alloc_hint = em->block_start;
769 read_unlock(&em_tree->lock);
775 * when extent_io.c finds a delayed allocation range in the file,
776 * the call backs end up in this code. The basic idea is to
777 * allocate extents on disk for the range, and create ordered data structs
778 * in ram to track those extents.
780 * locked_page is the page that writepage had locked already. We use
781 * it to make sure we don't do extra locks or unlocks.
783 * *page_started is set to one if we unlock locked_page and do everything
784 * required to start IO on it. It may be clean and already done with
787 static noinline int cow_file_range(struct inode *inode,
788 struct page *locked_page,
789 u64 start, u64 end, int *page_started,
790 unsigned long *nr_written,
793 struct btrfs_root *root = BTRFS_I(inode)->root;
794 struct btrfs_trans_handle *trans;
797 unsigned long ram_size;
800 u64 blocksize = root->sectorsize;
801 struct btrfs_key ins;
802 struct extent_map *em;
803 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
806 BUG_ON(btrfs_is_free_space_inode(root, inode));
807 trans = btrfs_join_transaction(root);
808 BUG_ON(IS_ERR(trans));
809 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
811 num_bytes = (end - start + blocksize) & ~(blocksize - 1);
812 num_bytes = max(blocksize, num_bytes);
813 disk_num_bytes = num_bytes;
816 /* if this is a small write inside eof, kick off defrag */
817 if (end <= BTRFS_I(inode)->disk_i_size && num_bytes < 64 * 1024)
818 btrfs_add_inode_defrag(trans, inode);
821 /* lets try to make an inline extent */
822 ret = cow_file_range_inline(trans, root, inode,
823 start, end, 0, 0, NULL);
825 extent_clear_unlock_delalloc(inode,
826 &BTRFS_I(inode)->io_tree,
828 EXTENT_CLEAR_UNLOCK_PAGE |
829 EXTENT_CLEAR_UNLOCK |
830 EXTENT_CLEAR_DELALLOC |
832 EXTENT_SET_WRITEBACK |
833 EXTENT_END_WRITEBACK);
835 *nr_written = *nr_written +
836 (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
843 BUG_ON(disk_num_bytes >
844 btrfs_super_total_bytes(root->fs_info->super_copy));
846 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
847 btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
849 while (disk_num_bytes > 0) {
852 cur_alloc_size = disk_num_bytes;
853 ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
854 root->sectorsize, 0, alloc_hint,
858 em = alloc_extent_map();
861 em->orig_start = em->start;
862 ram_size = ins.offset;
863 em->len = ins.offset;
865 em->block_start = ins.objectid;
866 em->block_len = ins.offset;
867 em->bdev = root->fs_info->fs_devices->latest_bdev;
868 set_bit(EXTENT_FLAG_PINNED, &em->flags);
871 write_lock(&em_tree->lock);
872 ret = add_extent_mapping(em_tree, em);
873 write_unlock(&em_tree->lock);
874 if (ret != -EEXIST) {
878 btrfs_drop_extent_cache(inode, start,
879 start + ram_size - 1, 0);
882 cur_alloc_size = ins.offset;
883 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
884 ram_size, cur_alloc_size, 0);
887 if (root->root_key.objectid ==
888 BTRFS_DATA_RELOC_TREE_OBJECTID) {
889 ret = btrfs_reloc_clone_csums(inode, start,
894 if (disk_num_bytes < cur_alloc_size)
897 /* we're not doing compressed IO, don't unlock the first
898 * page (which the caller expects to stay locked), don't
899 * clear any dirty bits and don't set any writeback bits
901 * Do set the Private2 bit so we know this page was properly
902 * setup for writepage
904 op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0;
905 op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
908 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
909 start, start + ram_size - 1,
911 disk_num_bytes -= cur_alloc_size;
912 num_bytes -= cur_alloc_size;
913 alloc_hint = ins.objectid + ins.offset;
914 start += cur_alloc_size;
918 btrfs_end_transaction(trans, root);
924 * work queue call back to started compression on a file and pages
926 static noinline void async_cow_start(struct btrfs_work *work)
928 struct async_cow *async_cow;
930 async_cow = container_of(work, struct async_cow, work);
932 compress_file_range(async_cow->inode, async_cow->locked_page,
933 async_cow->start, async_cow->end, async_cow,
936 async_cow->inode = NULL;
940 * work queue call back to submit previously compressed pages
942 static noinline void async_cow_submit(struct btrfs_work *work)
944 struct async_cow *async_cow;
945 struct btrfs_root *root;
946 unsigned long nr_pages;
948 async_cow = container_of(work, struct async_cow, work);
950 root = async_cow->root;
951 nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >>
954 atomic_sub(nr_pages, &root->fs_info->async_delalloc_pages);
956 if (atomic_read(&root->fs_info->async_delalloc_pages) <
958 waitqueue_active(&root->fs_info->async_submit_wait))
959 wake_up(&root->fs_info->async_submit_wait);
961 if (async_cow->inode)
962 submit_compressed_extents(async_cow->inode, async_cow);
965 static noinline void async_cow_free(struct btrfs_work *work)
967 struct async_cow *async_cow;
968 async_cow = container_of(work, struct async_cow, work);
972 static int cow_file_range_async(struct inode *inode, struct page *locked_page,
973 u64 start, u64 end, int *page_started,
974 unsigned long *nr_written)
976 struct async_cow *async_cow;
977 struct btrfs_root *root = BTRFS_I(inode)->root;
978 unsigned long nr_pages;
980 int limit = 10 * 1024 * 1042;
982 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
983 1, 0, NULL, GFP_NOFS);
984 while (start < end) {
985 async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
987 async_cow->inode = inode;
988 async_cow->root = root;
989 async_cow->locked_page = locked_page;
990 async_cow->start = start;
992 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
995 cur_end = min(end, start + 512 * 1024 - 1);
997 async_cow->end = cur_end;
998 INIT_LIST_HEAD(&async_cow->extents);
1000 async_cow->work.func = async_cow_start;
1001 async_cow->work.ordered_func = async_cow_submit;
1002 async_cow->work.ordered_free = async_cow_free;
1003 async_cow->work.flags = 0;
1005 nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >>
1007 atomic_add(nr_pages, &root->fs_info->async_delalloc_pages);
1009 btrfs_queue_worker(&root->fs_info->delalloc_workers,
1012 if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) {
1013 wait_event(root->fs_info->async_submit_wait,
1014 (atomic_read(&root->fs_info->async_delalloc_pages) <
1018 while (atomic_read(&root->fs_info->async_submit_draining) &&
1019 atomic_read(&root->fs_info->async_delalloc_pages)) {
1020 wait_event(root->fs_info->async_submit_wait,
1021 (atomic_read(&root->fs_info->async_delalloc_pages) ==
1025 *nr_written += nr_pages;
1026 start = cur_end + 1;
1032 static noinline int csum_exist_in_range(struct btrfs_root *root,
1033 u64 bytenr, u64 num_bytes)
1036 struct btrfs_ordered_sum *sums;
1039 ret = btrfs_lookup_csums_range(root->fs_info->csum_root, bytenr,
1040 bytenr + num_bytes - 1, &list, 0);
1041 if (ret == 0 && list_empty(&list))
1044 while (!list_empty(&list)) {
1045 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
1046 list_del(&sums->list);
1053 * when nowcow writeback call back. This checks for snapshots or COW copies
1054 * of the extents that exist in the file, and COWs the file as required.
1056 * If no cow copies or snapshots exist, we write directly to the existing
1059 static noinline int run_delalloc_nocow(struct inode *inode,
1060 struct page *locked_page,
1061 u64 start, u64 end, int *page_started, int force,
1062 unsigned long *nr_written)
1064 struct btrfs_root *root = BTRFS_I(inode)->root;
1065 struct btrfs_trans_handle *trans;
1066 struct extent_buffer *leaf;
1067 struct btrfs_path *path;
1068 struct btrfs_file_extent_item *fi;
1069 struct btrfs_key found_key;
1082 u64 ino = btrfs_ino(inode);
1084 path = btrfs_alloc_path();
1088 nolock = btrfs_is_free_space_inode(root, inode);
1091 trans = btrfs_join_transaction_nolock(root);
1093 trans = btrfs_join_transaction(root);
1095 BUG_ON(IS_ERR(trans));
1096 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1098 cow_start = (u64)-1;
1101 ret = btrfs_lookup_file_extent(trans, root, path, ino,
1104 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1105 leaf = path->nodes[0];
1106 btrfs_item_key_to_cpu(leaf, &found_key,
1107 path->slots[0] - 1);
1108 if (found_key.objectid == ino &&
1109 found_key.type == BTRFS_EXTENT_DATA_KEY)
1114 leaf = path->nodes[0];
1115 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1116 ret = btrfs_next_leaf(root, path);
1121 leaf = path->nodes[0];
1127 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1129 if (found_key.objectid > ino ||
1130 found_key.type > BTRFS_EXTENT_DATA_KEY ||
1131 found_key.offset > end)
1134 if (found_key.offset > cur_offset) {
1135 extent_end = found_key.offset;
1140 fi = btrfs_item_ptr(leaf, path->slots[0],
1141 struct btrfs_file_extent_item);
1142 extent_type = btrfs_file_extent_type(leaf, fi);
1144 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1145 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1146 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1147 extent_offset = btrfs_file_extent_offset(leaf, fi);
1148 extent_end = found_key.offset +
1149 btrfs_file_extent_num_bytes(leaf, fi);
1150 if (extent_end <= start) {
1154 if (disk_bytenr == 0)
1156 if (btrfs_file_extent_compression(leaf, fi) ||
1157 btrfs_file_extent_encryption(leaf, fi) ||
1158 btrfs_file_extent_other_encoding(leaf, fi))
1160 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1162 if (btrfs_extent_readonly(root, disk_bytenr))
1164 if (btrfs_cross_ref_exist(trans, root, ino,
1166 extent_offset, disk_bytenr))
1168 disk_bytenr += extent_offset;
1169 disk_bytenr += cur_offset - found_key.offset;
1170 num_bytes = min(end + 1, extent_end) - cur_offset;
1172 * force cow if csum exists in the range.
1173 * this ensure that csum for a given extent are
1174 * either valid or do not exist.
1176 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
1179 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1180 extent_end = found_key.offset +
1181 btrfs_file_extent_inline_len(leaf,
1182 path->slots[0], fi);
1183 extent_end = ALIGN(extent_end, root->sectorsize);
1188 if (extent_end <= start) {
1193 if (cow_start == (u64)-1)
1194 cow_start = cur_offset;
1195 cur_offset = extent_end;
1196 if (cur_offset > end)
1202 btrfs_release_path(path);
1203 if (cow_start != (u64)-1) {
1204 ret = cow_file_range(inode, locked_page, cow_start,
1205 found_key.offset - 1, page_started,
1208 cow_start = (u64)-1;
1211 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1212 struct extent_map *em;
1213 struct extent_map_tree *em_tree;
1214 em_tree = &BTRFS_I(inode)->extent_tree;
1215 em = alloc_extent_map();
1217 em->start = cur_offset;
1218 em->orig_start = em->start;
1219 em->len = num_bytes;
1220 em->block_len = num_bytes;
1221 em->block_start = disk_bytenr;
1222 em->bdev = root->fs_info->fs_devices->latest_bdev;
1223 set_bit(EXTENT_FLAG_PINNED, &em->flags);
1225 write_lock(&em_tree->lock);
1226 ret = add_extent_mapping(em_tree, em);
1227 write_unlock(&em_tree->lock);
1228 if (ret != -EEXIST) {
1229 free_extent_map(em);
1232 btrfs_drop_extent_cache(inode, em->start,
1233 em->start + em->len - 1, 0);
1235 type = BTRFS_ORDERED_PREALLOC;
1237 type = BTRFS_ORDERED_NOCOW;
1240 ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr,
1241 num_bytes, num_bytes, type);
1244 if (root->root_key.objectid ==
1245 BTRFS_DATA_RELOC_TREE_OBJECTID) {
1246 ret = btrfs_reloc_clone_csums(inode, cur_offset,
1251 extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
1252 cur_offset, cur_offset + num_bytes - 1,
1253 locked_page, EXTENT_CLEAR_UNLOCK_PAGE |
1254 EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
1255 EXTENT_SET_PRIVATE2);
1256 cur_offset = extent_end;
1257 if (cur_offset > end)
1260 btrfs_release_path(path);
1262 if (cur_offset <= end && cow_start == (u64)-1)
1263 cow_start = cur_offset;
1264 if (cow_start != (u64)-1) {
1265 ret = cow_file_range(inode, locked_page, cow_start, end,
1266 page_started, nr_written, 1);
1271 ret = btrfs_end_transaction_nolock(trans, root);
1274 ret = btrfs_end_transaction(trans, root);
1277 btrfs_free_path(path);
1282 * extent_io.c call back to do delayed allocation processing
1284 static int run_delalloc_range(struct inode *inode, struct page *locked_page,
1285 u64 start, u64 end, int *page_started,
1286 unsigned long *nr_written)
1289 struct btrfs_root *root = BTRFS_I(inode)->root;
1291 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW)
1292 ret = run_delalloc_nocow(inode, locked_page, start, end,
1293 page_started, 1, nr_written);
1294 else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)
1295 ret = run_delalloc_nocow(inode, locked_page, start, end,
1296 page_started, 0, nr_written);
1297 else if (!btrfs_test_opt(root, COMPRESS) &&
1298 !(BTRFS_I(inode)->force_compress) &&
1299 !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))
1300 ret = cow_file_range(inode, locked_page, start, end,
1301 page_started, nr_written, 1);
1303 ret = cow_file_range_async(inode, locked_page, start, end,
1304 page_started, nr_written);
1308 static void btrfs_split_extent_hook(struct inode *inode,
1309 struct extent_state *orig, u64 split)
1311 /* not delalloc, ignore it */
1312 if (!(orig->state & EXTENT_DELALLOC))
1315 spin_lock(&BTRFS_I(inode)->lock);
1316 BTRFS_I(inode)->outstanding_extents++;
1317 spin_unlock(&BTRFS_I(inode)->lock);
1321 * extent_io.c merge_extent_hook, used to track merged delayed allocation
1322 * extents so we can keep track of new extents that are just merged onto old
1323 * extents, such as when we are doing sequential writes, so we can properly
1324 * account for the metadata space we'll need.
1326 static void btrfs_merge_extent_hook(struct inode *inode,
1327 struct extent_state *new,
1328 struct extent_state *other)
1330 /* not delalloc, ignore it */
1331 if (!(other->state & EXTENT_DELALLOC))
1334 spin_lock(&BTRFS_I(inode)->lock);
1335 BTRFS_I(inode)->outstanding_extents--;
1336 spin_unlock(&BTRFS_I(inode)->lock);
1340 * extent_io.c set_bit_hook, used to track delayed allocation
1341 * bytes in this file, and to maintain the list of inodes that
1342 * have pending delalloc work to be done.
1344 static void btrfs_set_bit_hook(struct inode *inode,
1345 struct extent_state *state, int *bits)
1349 * set_bit and clear bit hooks normally require _irqsave/restore
1350 * but in this case, we are only testing for the DELALLOC
1351 * bit, which is only set or cleared with irqs on
1353 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1354 struct btrfs_root *root = BTRFS_I(inode)->root;
1355 u64 len = state->end + 1 - state->start;
1356 bool do_list = !btrfs_is_free_space_inode(root, inode);
1358 if (*bits & EXTENT_FIRST_DELALLOC) {
1359 *bits &= ~EXTENT_FIRST_DELALLOC;
1361 spin_lock(&BTRFS_I(inode)->lock);
1362 BTRFS_I(inode)->outstanding_extents++;
1363 spin_unlock(&BTRFS_I(inode)->lock);
1366 spin_lock(&root->fs_info->delalloc_lock);
1367 BTRFS_I(inode)->delalloc_bytes += len;
1368 root->fs_info->delalloc_bytes += len;
1369 if (do_list && list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1370 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1371 &root->fs_info->delalloc_inodes);
1373 spin_unlock(&root->fs_info->delalloc_lock);
1378 * extent_io.c clear_bit_hook, see set_bit_hook for why
1380 static void btrfs_clear_bit_hook(struct inode *inode,
1381 struct extent_state *state, int *bits)
1384 * set_bit and clear bit hooks normally require _irqsave/restore
1385 * but in this case, we are only testing for the DELALLOC
1386 * bit, which is only set or cleared with irqs on
1388 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
1389 struct btrfs_root *root = BTRFS_I(inode)->root;
1390 u64 len = state->end + 1 - state->start;
1391 bool do_list = !btrfs_is_free_space_inode(root, inode);
1393 if (*bits & EXTENT_FIRST_DELALLOC) {
1394 *bits &= ~EXTENT_FIRST_DELALLOC;
1395 } else if (!(*bits & EXTENT_DO_ACCOUNTING)) {
1396 spin_lock(&BTRFS_I(inode)->lock);
1397 BTRFS_I(inode)->outstanding_extents--;
1398 spin_unlock(&BTRFS_I(inode)->lock);
1401 if (*bits & EXTENT_DO_ACCOUNTING)
1402 btrfs_delalloc_release_metadata(inode, len);
1404 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
1406 btrfs_free_reserved_data_space(inode, len);
1408 spin_lock(&root->fs_info->delalloc_lock);
1409 root->fs_info->delalloc_bytes -= len;
1410 BTRFS_I(inode)->delalloc_bytes -= len;
1412 if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 &&
1413 !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1414 list_del_init(&BTRFS_I(inode)->delalloc_inodes);
1416 spin_unlock(&root->fs_info->delalloc_lock);
1421 * extent_io.c merge_bio_hook, this must check the chunk tree to make sure
1422 * we don't create bios that span stripes or chunks
1424 int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
1425 size_t size, struct bio *bio,
1426 unsigned long bio_flags)
1428 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
1429 struct btrfs_mapping_tree *map_tree;
1430 u64 logical = (u64)bio->bi_sector << 9;
1435 if (bio_flags & EXTENT_BIO_COMPRESSED)
1438 length = bio->bi_size;
1439 map_tree = &root->fs_info->mapping_tree;
1440 map_length = length;
1441 ret = btrfs_map_block(map_tree, READ, logical,
1442 &map_length, NULL, 0);
1444 if (map_length < length + size)
1450 * in order to insert checksums into the metadata in large chunks,
1451 * we wait until bio submission time. All the pages in the bio are
1452 * checksummed and sums are attached onto the ordered extent record.
1454 * At IO completion time the cums attached on the ordered extent record
1455 * are inserted into the btree
1457 static int __btrfs_submit_bio_start(struct inode *inode, int rw,
1458 struct bio *bio, int mirror_num,
1459 unsigned long bio_flags,
1462 struct btrfs_root *root = BTRFS_I(inode)->root;
1465 ret = btrfs_csum_one_bio(root, inode, bio, 0, 0);
1471 * in order to insert checksums into the metadata in large chunks,
1472 * we wait until bio submission time. All the pages in the bio are
1473 * checksummed and sums are attached onto the ordered extent record.
1475 * At IO completion time the cums attached on the ordered extent record
1476 * are inserted into the btree
1478 static int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
1479 int mirror_num, unsigned long bio_flags,
1482 struct btrfs_root *root = BTRFS_I(inode)->root;
1483 return btrfs_map_bio(root, rw, bio, mirror_num, 1);
1487 * extent_io.c submission hook. This does the right thing for csum calculation
1488 * on write, or reading the csums from the tree before a read
1490 static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
1491 int mirror_num, unsigned long bio_flags,
1494 struct btrfs_root *root = BTRFS_I(inode)->root;
1498 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
1500 if (btrfs_is_free_space_inode(root, inode))
1501 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 2);
1503 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
1506 if (!(rw & REQ_WRITE)) {
1507 if (bio_flags & EXTENT_BIO_COMPRESSED) {
1508 return btrfs_submit_compressed_read(inode, bio,
1509 mirror_num, bio_flags);
1510 } else if (!skip_sum) {
1511 ret = btrfs_lookup_bio_sums(root, inode, bio, NULL);
1516 } else if (!skip_sum) {
1517 /* csum items have already been cloned */
1518 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
1520 /* we're doing a write, do the async checksumming */
1521 return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
1522 inode, rw, bio, mirror_num,
1523 bio_flags, bio_offset,
1524 __btrfs_submit_bio_start,
1525 __btrfs_submit_bio_done);
1529 return btrfs_map_bio(root, rw, bio, mirror_num, 0);
1533 * given a list of ordered sums record them in the inode. This happens
1534 * at IO completion time based on sums calculated at bio submission time.
1536 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
1537 struct inode *inode, u64 file_offset,
1538 struct list_head *list)
1540 struct btrfs_ordered_sum *sum;
1542 list_for_each_entry(sum, list, list) {
1543 btrfs_csum_file_blocks(trans,
1544 BTRFS_I(inode)->root->fs_info->csum_root, sum);
1549 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
1550 struct extent_state **cached_state)
1552 if ((end & (PAGE_CACHE_SIZE - 1)) == 0)
1554 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
1555 cached_state, GFP_NOFS);
1558 /* see btrfs_writepage_start_hook for details on why this is required */
1559 struct btrfs_writepage_fixup {
1561 struct btrfs_work work;
1564 static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
1566 struct btrfs_writepage_fixup *fixup;
1567 struct btrfs_ordered_extent *ordered;
1568 struct extent_state *cached_state = NULL;
1570 struct inode *inode;
1574 fixup = container_of(work, struct btrfs_writepage_fixup, work);
1578 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
1579 ClearPageChecked(page);
1583 inode = page->mapping->host;
1584 page_start = page_offset(page);
1585 page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
1587 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 0,
1588 &cached_state, GFP_NOFS);
1590 /* already ordered? We're done */
1591 if (PagePrivate2(page))
1594 ordered = btrfs_lookup_ordered_extent(inode, page_start);
1596 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start,
1597 page_end, &cached_state, GFP_NOFS);
1599 btrfs_start_ordered_extent(inode, ordered, 1);
1604 btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state);
1605 ClearPageChecked(page);
1607 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
1608 &cached_state, GFP_NOFS);
1611 page_cache_release(page);
1616 * There are a few paths in the higher layers of the kernel that directly
1617 * set the page dirty bit without asking the filesystem if it is a
1618 * good idea. This causes problems because we want to make sure COW
1619 * properly happens and the data=ordered rules are followed.
1621 * In our case any range that doesn't have the ORDERED bit set
1622 * hasn't been properly setup for IO. We kick off an async process
1623 * to fix it up. The async helper will wait for ordered extents, set
1624 * the delalloc bit and make it safe to write the page.
1626 static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
1628 struct inode *inode = page->mapping->host;
1629 struct btrfs_writepage_fixup *fixup;
1630 struct btrfs_root *root = BTRFS_I(inode)->root;
1632 /* this page is properly in the ordered list */
1633 if (TestClearPagePrivate2(page))
1636 if (PageChecked(page))
1639 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
1643 SetPageChecked(page);
1644 page_cache_get(page);
1645 fixup->work.func = btrfs_writepage_fixup_worker;
1647 btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
1651 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
1652 struct inode *inode, u64 file_pos,
1653 u64 disk_bytenr, u64 disk_num_bytes,
1654 u64 num_bytes, u64 ram_bytes,
1655 u8 compression, u8 encryption,
1656 u16 other_encoding, int extent_type)
1658 struct btrfs_root *root = BTRFS_I(inode)->root;
1659 struct btrfs_file_extent_item *fi;
1660 struct btrfs_path *path;
1661 struct extent_buffer *leaf;
1662 struct btrfs_key ins;
1666 path = btrfs_alloc_path();
1670 path->leave_spinning = 1;
1673 * we may be replacing one extent in the tree with another.
1674 * The new extent is pinned in the extent map, and we don't want
1675 * to drop it from the cache until it is completely in the btree.
1677 * So, tell btrfs_drop_extents to leave this extent in the cache.
1678 * the caller is expected to unpin it and allow it to be merged
1681 ret = btrfs_drop_extents(trans, inode, file_pos, file_pos + num_bytes,
1685 ins.objectid = btrfs_ino(inode);
1686 ins.offset = file_pos;
1687 ins.type = BTRFS_EXTENT_DATA_KEY;
1688 ret = btrfs_insert_empty_item(trans, root, path, &ins, sizeof(*fi));
1690 leaf = path->nodes[0];
1691 fi = btrfs_item_ptr(leaf, path->slots[0],
1692 struct btrfs_file_extent_item);
1693 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
1694 btrfs_set_file_extent_type(leaf, fi, extent_type);
1695 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
1696 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
1697 btrfs_set_file_extent_offset(leaf, fi, 0);
1698 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
1699 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
1700 btrfs_set_file_extent_compression(leaf, fi, compression);
1701 btrfs_set_file_extent_encryption(leaf, fi, encryption);
1702 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
1704 btrfs_unlock_up_safe(path, 1);
1705 btrfs_set_lock_blocking(leaf);
1707 btrfs_mark_buffer_dirty(leaf);
1709 inode_add_bytes(inode, num_bytes);
1711 ins.objectid = disk_bytenr;
1712 ins.offset = disk_num_bytes;
1713 ins.type = BTRFS_EXTENT_ITEM_KEY;
1714 ret = btrfs_alloc_reserved_file_extent(trans, root,
1715 root->root_key.objectid,
1716 btrfs_ino(inode), file_pos, &ins);
1718 btrfs_free_path(path);
1724 * helper function for btrfs_finish_ordered_io, this
1725 * just reads in some of the csum leaves to prime them into ram
1726 * before we start the transaction. It limits the amount of btree
1727 * reads required while inside the transaction.
1729 /* as ordered data IO finishes, this gets called so we can finish
1730 * an ordered extent if the range of bytes in the file it covers are
1733 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
1735 struct btrfs_root *root = BTRFS_I(inode)->root;
1736 struct btrfs_trans_handle *trans = NULL;
1737 struct btrfs_ordered_extent *ordered_extent = NULL;
1738 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1739 struct extent_state *cached_state = NULL;
1740 int compress_type = 0;
1744 ret = btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
1748 BUG_ON(!ordered_extent);
1750 nolock = btrfs_is_free_space_inode(root, inode);
1752 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
1753 BUG_ON(!list_empty(&ordered_extent->list));
1754 ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
1757 trans = btrfs_join_transaction_nolock(root);
1759 trans = btrfs_join_transaction(root);
1760 BUG_ON(IS_ERR(trans));
1761 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1762 ret = btrfs_update_inode_fallback(trans, root, inode);
1768 lock_extent_bits(io_tree, ordered_extent->file_offset,
1769 ordered_extent->file_offset + ordered_extent->len - 1,
1770 0, &cached_state, GFP_NOFS);
1773 trans = btrfs_join_transaction_nolock(root);
1775 trans = btrfs_join_transaction(root);
1776 BUG_ON(IS_ERR(trans));
1777 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
1779 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
1780 compress_type = ordered_extent->compress_type;
1781 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
1782 BUG_ON(compress_type);
1783 ret = btrfs_mark_extent_written(trans, inode,
1784 ordered_extent->file_offset,
1785 ordered_extent->file_offset +
1786 ordered_extent->len);
1789 BUG_ON(root == root->fs_info->tree_root);
1790 ret = insert_reserved_file_extent(trans, inode,
1791 ordered_extent->file_offset,
1792 ordered_extent->start,
1793 ordered_extent->disk_len,
1794 ordered_extent->len,
1795 ordered_extent->len,
1796 compress_type, 0, 0,
1797 BTRFS_FILE_EXTENT_REG);
1798 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
1799 ordered_extent->file_offset,
1800 ordered_extent->len);
1803 unlock_extent_cached(io_tree, ordered_extent->file_offset,
1804 ordered_extent->file_offset +
1805 ordered_extent->len - 1, &cached_state, GFP_NOFS);
1807 add_pending_csums(trans, inode, ordered_extent->file_offset,
1808 &ordered_extent->list);
1810 ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent);
1811 if (!ret || !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
1812 ret = btrfs_update_inode_fallback(trans, root, inode);
1817 if (root != root->fs_info->tree_root)
1818 btrfs_delalloc_release_metadata(inode, ordered_extent->len);
1821 btrfs_end_transaction_nolock(trans, root);
1823 btrfs_end_transaction(trans, root);
1827 btrfs_put_ordered_extent(ordered_extent);
1828 /* once for the tree */
1829 btrfs_put_ordered_extent(ordered_extent);
1834 static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
1835 struct extent_state *state, int uptodate)
1837 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate);
1839 ClearPagePrivate2(page);
1840 return btrfs_finish_ordered_io(page->mapping->host, start, end);
1844 * when reads are done, we need to check csums to verify the data is correct
1845 * if there's a match, we allow the bio to finish. If not, the code in
1846 * extent_io.c will try to find good copies for us.
1848 static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
1849 struct extent_state *state)
1851 size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
1852 struct inode *inode = page->mapping->host;
1853 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1855 u64 private = ~(u32)0;
1857 struct btrfs_root *root = BTRFS_I(inode)->root;
1860 if (PageChecked(page)) {
1861 ClearPageChecked(page);
1865 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
1868 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
1869 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
1870 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM,
1875 if (state && state->start == start) {
1876 private = state->private;
1879 ret = get_state_private(io_tree, start, &private);
1881 kaddr = kmap_atomic(page, KM_USER0);
1885 csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1);
1886 btrfs_csum_final(csum, (char *)&csum);
1887 if (csum != private)
1890 kunmap_atomic(kaddr, KM_USER0);
1895 printk_ratelimited(KERN_INFO "btrfs csum failed ino %llu off %llu csum %u "
1897 (unsigned long long)btrfs_ino(page->mapping->host),
1898 (unsigned long long)start, csum,
1899 (unsigned long long)private);
1900 memset(kaddr + offset, 1, end - start + 1);
1901 flush_dcache_page(page);
1902 kunmap_atomic(kaddr, KM_USER0);
1908 struct delayed_iput {
1909 struct list_head list;
1910 struct inode *inode;
1913 void btrfs_add_delayed_iput(struct inode *inode)
1915 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
1916 struct delayed_iput *delayed;
1918 if (atomic_add_unless(&inode->i_count, -1, 1))
1921 delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL);
1922 delayed->inode = inode;
1924 spin_lock(&fs_info->delayed_iput_lock);
1925 list_add_tail(&delayed->list, &fs_info->delayed_iputs);
1926 spin_unlock(&fs_info->delayed_iput_lock);
1929 void btrfs_run_delayed_iputs(struct btrfs_root *root)
1932 struct btrfs_fs_info *fs_info = root->fs_info;
1933 struct delayed_iput *delayed;
1936 spin_lock(&fs_info->delayed_iput_lock);
1937 empty = list_empty(&fs_info->delayed_iputs);
1938 spin_unlock(&fs_info->delayed_iput_lock);
1942 down_read(&root->fs_info->cleanup_work_sem);
1943 spin_lock(&fs_info->delayed_iput_lock);
1944 list_splice_init(&fs_info->delayed_iputs, &list);
1945 spin_unlock(&fs_info->delayed_iput_lock);
1947 while (!list_empty(&list)) {
1948 delayed = list_entry(list.next, struct delayed_iput, list);
1949 list_del(&delayed->list);
1950 iput(delayed->inode);
1953 up_read(&root->fs_info->cleanup_work_sem);
1956 enum btrfs_orphan_cleanup_state {
1957 ORPHAN_CLEANUP_STARTED = 1,
1958 ORPHAN_CLEANUP_DONE = 2,
1962 * This is called in transaction commmit time. If there are no orphan
1963 * files in the subvolume, it removes orphan item and frees block_rsv
1966 void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans,
1967 struct btrfs_root *root)
1971 if (!list_empty(&root->orphan_list) ||
1972 root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE)
1975 if (root->orphan_item_inserted &&
1976 btrfs_root_refs(&root->root_item) > 0) {
1977 ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root,
1978 root->root_key.objectid);
1980 root->orphan_item_inserted = 0;
1983 if (root->orphan_block_rsv) {
1984 WARN_ON(root->orphan_block_rsv->size > 0);
1985 btrfs_free_block_rsv(root, root->orphan_block_rsv);
1986 root->orphan_block_rsv = NULL;
1991 * This creates an orphan entry for the given inode in case something goes
1992 * wrong in the middle of an unlink/truncate.
1994 * NOTE: caller of this function should reserve 5 units of metadata for
1997 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
1999 struct btrfs_root *root = BTRFS_I(inode)->root;
2000 struct btrfs_block_rsv *block_rsv = NULL;
2005 if (!root->orphan_block_rsv) {
2006 block_rsv = btrfs_alloc_block_rsv(root);
2011 spin_lock(&root->orphan_lock);
2012 if (!root->orphan_block_rsv) {
2013 root->orphan_block_rsv = block_rsv;
2014 } else if (block_rsv) {
2015 btrfs_free_block_rsv(root, block_rsv);
2019 if (list_empty(&BTRFS_I(inode)->i_orphan)) {
2020 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
2023 * For proper ENOSPC handling, we should do orphan
2024 * cleanup when mounting. But this introduces backward
2025 * compatibility issue.
2027 if (!xchg(&root->orphan_item_inserted, 1))
2035 if (!BTRFS_I(inode)->orphan_meta_reserved) {
2036 BTRFS_I(inode)->orphan_meta_reserved = 1;
2039 spin_unlock(&root->orphan_lock);
2041 /* grab metadata reservation from transaction handle */
2043 ret = btrfs_orphan_reserve_metadata(trans, inode);
2047 /* insert an orphan item to track this unlinked/truncated file */
2049 ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode));
2050 BUG_ON(ret && ret != -EEXIST);
2053 /* insert an orphan item to track subvolume contains orphan files */
2055 ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
2056 root->root_key.objectid);
2063 * We have done the truncate/delete so we can go ahead and remove the orphan
2064 * item for this particular inode.
2066 int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode)
2068 struct btrfs_root *root = BTRFS_I(inode)->root;
2069 int delete_item = 0;
2070 int release_rsv = 0;
2073 spin_lock(&root->orphan_lock);
2074 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
2075 list_del_init(&BTRFS_I(inode)->i_orphan);
2079 if (BTRFS_I(inode)->orphan_meta_reserved) {
2080 BTRFS_I(inode)->orphan_meta_reserved = 0;
2083 spin_unlock(&root->orphan_lock);
2085 if (trans && delete_item) {
2086 ret = btrfs_del_orphan_item(trans, root, btrfs_ino(inode));
2091 btrfs_orphan_release_metadata(inode);
2097 * this cleans up any orphans that may be left on the list from the last use
2100 int btrfs_orphan_cleanup(struct btrfs_root *root)
2102 struct btrfs_path *path;
2103 struct extent_buffer *leaf;
2104 struct btrfs_key key, found_key;
2105 struct btrfs_trans_handle *trans;
2106 struct inode *inode;
2107 u64 last_objectid = 0;
2108 int ret = 0, nr_unlink = 0, nr_truncate = 0;
2110 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
2113 path = btrfs_alloc_path();
2120 key.objectid = BTRFS_ORPHAN_OBJECTID;
2121 btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
2122 key.offset = (u64)-1;
2125 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2130 * if ret == 0 means we found what we were searching for, which
2131 * is weird, but possible, so only screw with path if we didn't
2132 * find the key and see if we have stuff that matches
2136 if (path->slots[0] == 0)
2141 /* pull out the item */
2142 leaf = path->nodes[0];
2143 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2145 /* make sure the item matches what we want */
2146 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
2148 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
2151 /* release the path since we're done with it */
2152 btrfs_release_path(path);
2155 * this is where we are basically btrfs_lookup, without the
2156 * crossing root thing. we store the inode number in the
2157 * offset of the orphan item.
2160 if (found_key.offset == last_objectid) {
2161 printk(KERN_ERR "btrfs: Error removing orphan entry, "
2162 "stopping orphan cleanup\n");
2167 last_objectid = found_key.offset;
2169 found_key.objectid = found_key.offset;
2170 found_key.type = BTRFS_INODE_ITEM_KEY;
2171 found_key.offset = 0;
2172 inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL);
2173 ret = PTR_RET(inode);
2174 if (ret && ret != -ESTALE)
2177 if (ret == -ESTALE && root == root->fs_info->tree_root) {
2178 struct btrfs_root *dead_root;
2179 struct btrfs_fs_info *fs_info = root->fs_info;
2180 int is_dead_root = 0;
2183 * this is an orphan in the tree root. Currently these
2184 * could come from 2 sources:
2185 * a) a snapshot deletion in progress
2186 * b) a free space cache inode
2187 * We need to distinguish those two, as the snapshot
2188 * orphan must not get deleted.
2189 * find_dead_roots already ran before us, so if this
2190 * is a snapshot deletion, we should find the root
2191 * in the dead_roots list
2193 spin_lock(&fs_info->trans_lock);
2194 list_for_each_entry(dead_root, &fs_info->dead_roots,
2196 if (dead_root->root_key.objectid ==
2197 found_key.objectid) {
2202 spin_unlock(&fs_info->trans_lock);
2204 /* prevent this orphan from being found again */
2205 key.offset = found_key.objectid - 1;
2210 * Inode is already gone but the orphan item is still there,
2211 * kill the orphan item.
2213 if (ret == -ESTALE) {
2214 trans = btrfs_start_transaction(root, 1);
2215 if (IS_ERR(trans)) {
2216 ret = PTR_ERR(trans);
2219 ret = btrfs_del_orphan_item(trans, root,
2220 found_key.objectid);
2222 btrfs_end_transaction(trans, root);
2227 * add this inode to the orphan list so btrfs_orphan_del does
2228 * the proper thing when we hit it
2230 spin_lock(&root->orphan_lock);
2231 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
2232 spin_unlock(&root->orphan_lock);
2234 /* if we have links, this was a truncate, lets do that */
2235 if (inode->i_nlink) {
2236 if (!S_ISREG(inode->i_mode)) {
2243 * Need to hold the imutex for reservation purposes, not
2244 * a huge deal here but I have a WARN_ON in
2245 * btrfs_delalloc_reserve_space to catch offenders.
2247 mutex_lock(&inode->i_mutex);
2248 ret = btrfs_truncate(inode);
2249 mutex_unlock(&inode->i_mutex);
2254 /* this will do delete_inode and everything for us */
2259 /* release the path since we're done with it */
2260 btrfs_release_path(path);
2262 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
2264 if (root->orphan_block_rsv)
2265 btrfs_block_rsv_release(root, root->orphan_block_rsv,
2268 if (root->orphan_block_rsv || root->orphan_item_inserted) {
2269 trans = btrfs_join_transaction(root);
2271 btrfs_end_transaction(trans, root);
2275 printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink);
2277 printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate);
2281 printk(KERN_CRIT "btrfs: could not do orphan cleanup %d\n", ret);
2282 btrfs_free_path(path);
2287 * very simple check to peek ahead in the leaf looking for xattrs. If we
2288 * don't find any xattrs, we know there can't be any acls.
2290 * slot is the slot the inode is in, objectid is the objectid of the inode
2292 static noinline int acls_after_inode_item(struct extent_buffer *leaf,
2293 int slot, u64 objectid)
2295 u32 nritems = btrfs_header_nritems(leaf);
2296 struct btrfs_key found_key;
2300 while (slot < nritems) {
2301 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2303 /* we found a different objectid, there must not be acls */
2304 if (found_key.objectid != objectid)
2307 /* we found an xattr, assume we've got an acl */
2308 if (found_key.type == BTRFS_XATTR_ITEM_KEY)
2312 * we found a key greater than an xattr key, there can't
2313 * be any acls later on
2315 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
2322 * it goes inode, inode backrefs, xattrs, extents,
2323 * so if there are a ton of hard links to an inode there can
2324 * be a lot of backrefs. Don't waste time searching too hard,
2325 * this is just an optimization
2330 /* we hit the end of the leaf before we found an xattr or
2331 * something larger than an xattr. We have to assume the inode
2338 * read an inode from the btree into the in-memory inode
2340 static void btrfs_read_locked_inode(struct inode *inode)
2342 struct btrfs_path *path;
2343 struct extent_buffer *leaf;
2344 struct btrfs_inode_item *inode_item;
2345 struct btrfs_timespec *tspec;
2346 struct btrfs_root *root = BTRFS_I(inode)->root;
2347 struct btrfs_key location;
2351 bool filled = false;
2353 ret = btrfs_fill_inode(inode, &rdev);
2357 path = btrfs_alloc_path();
2361 path->leave_spinning = 1;
2362 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
2364 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
2368 leaf = path->nodes[0];
2373 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2374 struct btrfs_inode_item);
2375 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
2376 set_nlink(inode, btrfs_inode_nlink(leaf, inode_item));
2377 inode->i_uid = btrfs_inode_uid(leaf, inode_item);
2378 inode->i_gid = btrfs_inode_gid(leaf, inode_item);
2379 btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
2381 tspec = btrfs_inode_atime(inode_item);
2382 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2383 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2385 tspec = btrfs_inode_mtime(inode_item);
2386 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2387 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2389 tspec = btrfs_inode_ctime(inode_item);
2390 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
2391 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
2393 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
2394 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
2395 BTRFS_I(inode)->sequence = btrfs_inode_sequence(leaf, inode_item);
2396 inode->i_generation = BTRFS_I(inode)->generation;
2398 rdev = btrfs_inode_rdev(leaf, inode_item);
2400 BTRFS_I(inode)->index_cnt = (u64)-1;
2401 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
2404 * try to precache a NULL acl entry for files that don't have
2405 * any xattrs or acls
2407 maybe_acls = acls_after_inode_item(leaf, path->slots[0],
2410 cache_no_acl(inode);
2412 btrfs_free_path(path);
2414 switch (inode->i_mode & S_IFMT) {
2416 inode->i_mapping->a_ops = &btrfs_aops;
2417 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2418 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
2419 inode->i_fop = &btrfs_file_operations;
2420 inode->i_op = &btrfs_file_inode_operations;
2423 inode->i_fop = &btrfs_dir_file_operations;
2424 if (root == root->fs_info->tree_root)
2425 inode->i_op = &btrfs_dir_ro_inode_operations;
2427 inode->i_op = &btrfs_dir_inode_operations;
2430 inode->i_op = &btrfs_symlink_inode_operations;
2431 inode->i_mapping->a_ops = &btrfs_symlink_aops;
2432 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2435 inode->i_op = &btrfs_special_inode_operations;
2436 init_special_inode(inode, inode->i_mode, rdev);
2440 btrfs_update_iflags(inode);
2444 btrfs_free_path(path);
2445 make_bad_inode(inode);
2449 * given a leaf and an inode, copy the inode fields into the leaf
2451 static void fill_inode_item(struct btrfs_trans_handle *trans,
2452 struct extent_buffer *leaf,
2453 struct btrfs_inode_item *item,
2454 struct inode *inode)
2456 btrfs_set_inode_uid(leaf, item, inode->i_uid);
2457 btrfs_set_inode_gid(leaf, item, inode->i_gid);
2458 btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size);
2459 btrfs_set_inode_mode(leaf, item, inode->i_mode);
2460 btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
2462 btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
2463 inode->i_atime.tv_sec);
2464 btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
2465 inode->i_atime.tv_nsec);
2467 btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
2468 inode->i_mtime.tv_sec);
2469 btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
2470 inode->i_mtime.tv_nsec);
2472 btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
2473 inode->i_ctime.tv_sec);
2474 btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
2475 inode->i_ctime.tv_nsec);
2477 btrfs_set_inode_nbytes(leaf, item, inode_get_bytes(inode));
2478 btrfs_set_inode_generation(leaf, item, BTRFS_I(inode)->generation);
2479 btrfs_set_inode_sequence(leaf, item, BTRFS_I(inode)->sequence);
2480 btrfs_set_inode_transid(leaf, item, trans->transid);
2481 btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
2482 btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
2483 btrfs_set_inode_block_group(leaf, item, 0);
2487 * copy everything in the in-memory inode into the btree.
2489 static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans,
2490 struct btrfs_root *root, struct inode *inode)
2492 struct btrfs_inode_item *inode_item;
2493 struct btrfs_path *path;
2494 struct extent_buffer *leaf;
2497 path = btrfs_alloc_path();
2501 path->leave_spinning = 1;
2502 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location,
2510 btrfs_unlock_up_safe(path, 1);
2511 leaf = path->nodes[0];
2512 inode_item = btrfs_item_ptr(leaf, path->slots[0],
2513 struct btrfs_inode_item);
2515 fill_inode_item(trans, leaf, inode_item, inode);
2516 btrfs_mark_buffer_dirty(leaf);
2517 btrfs_set_inode_last_trans(trans, inode);
2520 btrfs_free_path(path);
2525 * copy everything in the in-memory inode into the btree.
2527 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
2528 struct btrfs_root *root, struct inode *inode)
2533 * If the inode is a free space inode, we can deadlock during commit
2534 * if we put it into the delayed code.
2536 * The data relocation inode should also be directly updated
2539 if (!btrfs_is_free_space_inode(root, inode)
2540 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID) {
2541 ret = btrfs_delayed_update_inode(trans, root, inode);
2543 btrfs_set_inode_last_trans(trans, inode);
2547 return btrfs_update_inode_item(trans, root, inode);
2550 static noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
2551 struct btrfs_root *root, struct inode *inode)
2555 ret = btrfs_update_inode(trans, root, inode);
2557 return btrfs_update_inode_item(trans, root, inode);
2562 * unlink helper that gets used here in inode.c and in the tree logging
2563 * recovery code. It remove a link in a directory with a given name, and
2564 * also drops the back refs in the inode to the directory
2566 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
2567 struct btrfs_root *root,
2568 struct inode *dir, struct inode *inode,
2569 const char *name, int name_len)
2571 struct btrfs_path *path;
2573 struct extent_buffer *leaf;
2574 struct btrfs_dir_item *di;
2575 struct btrfs_key key;
2577 u64 ino = btrfs_ino(inode);
2578 u64 dir_ino = btrfs_ino(dir);
2580 path = btrfs_alloc_path();
2586 path->leave_spinning = 1;
2587 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
2588 name, name_len, -1);
2597 leaf = path->nodes[0];
2598 btrfs_dir_item_key_to_cpu(leaf, di, &key);
2599 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2602 btrfs_release_path(path);
2604 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino,
2607 printk(KERN_INFO "btrfs failed to delete reference to %.*s, "
2608 "inode %llu parent %llu\n", name_len, name,
2609 (unsigned long long)ino, (unsigned long long)dir_ino);
2613 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
2617 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len,
2619 BUG_ON(ret != 0 && ret != -ENOENT);
2621 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len,
2626 btrfs_free_path(path);
2630 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
2631 inode->i_ctime = dir->i_mtime = dir->i_ctime = CURRENT_TIME;
2632 btrfs_update_inode(trans, root, dir);
2637 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
2638 struct btrfs_root *root,
2639 struct inode *dir, struct inode *inode,
2640 const char *name, int name_len)
2643 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
2645 btrfs_drop_nlink(inode);
2646 ret = btrfs_update_inode(trans, root, inode);
2652 /* helper to check if there is any shared block in the path */
2653 static int check_path_shared(struct btrfs_root *root,
2654 struct btrfs_path *path)
2656 struct extent_buffer *eb;
2660 for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
2663 if (!path->nodes[level])
2665 eb = path->nodes[level];
2666 if (!btrfs_block_can_be_shared(root, eb))
2668 ret = btrfs_lookup_extent_info(NULL, root, eb->start, eb->len,
2677 * helper to start transaction for unlink and rmdir.
2679 * unlink and rmdir are special in btrfs, they do not always free space.
2680 * so in enospc case, we should make sure they will free space before
2681 * allowing them to use the global metadata reservation.
2683 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir,
2684 struct dentry *dentry)
2686 struct btrfs_trans_handle *trans;
2687 struct btrfs_root *root = BTRFS_I(dir)->root;
2688 struct btrfs_path *path;
2689 struct btrfs_inode_ref *ref;
2690 struct btrfs_dir_item *di;
2691 struct inode *inode = dentry->d_inode;
2696 u64 ino = btrfs_ino(inode);
2697 u64 dir_ino = btrfs_ino(dir);
2700 * 1 for the possible orphan item
2701 * 1 for the dir item
2702 * 1 for the dir index
2703 * 1 for the inode ref
2704 * 1 for the inode ref in the tree log
2705 * 2 for the dir entries in the log
2708 trans = btrfs_start_transaction(root, 8);
2709 if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
2712 if (ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
2713 return ERR_PTR(-ENOSPC);
2715 /* check if there is someone else holds reference */
2716 if (S_ISDIR(inode->i_mode) && atomic_read(&inode->i_count) > 1)
2717 return ERR_PTR(-ENOSPC);
2719 if (atomic_read(&inode->i_count) > 2)
2720 return ERR_PTR(-ENOSPC);
2722 if (xchg(&root->fs_info->enospc_unlink, 1))
2723 return ERR_PTR(-ENOSPC);
2725 path = btrfs_alloc_path();
2727 root->fs_info->enospc_unlink = 0;
2728 return ERR_PTR(-ENOMEM);
2731 /* 1 for the orphan item */
2732 trans = btrfs_start_transaction(root, 1);
2733 if (IS_ERR(trans)) {
2734 btrfs_free_path(path);
2735 root->fs_info->enospc_unlink = 0;
2739 path->skip_locking = 1;
2740 path->search_commit_root = 1;
2742 ret = btrfs_lookup_inode(trans, root, path,
2743 &BTRFS_I(dir)->location, 0);
2749 if (check_path_shared(root, path))
2754 btrfs_release_path(path);
2756 ret = btrfs_lookup_inode(trans, root, path,
2757 &BTRFS_I(inode)->location, 0);
2763 if (check_path_shared(root, path))
2768 btrfs_release_path(path);
2770 if (ret == 0 && S_ISREG(inode->i_mode)) {
2771 ret = btrfs_lookup_file_extent(trans, root, path,
2778 if (check_path_shared(root, path))
2780 btrfs_release_path(path);
2788 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
2789 dentry->d_name.name, dentry->d_name.len, 0);
2795 if (check_path_shared(root, path))
2801 btrfs_release_path(path);
2803 ref = btrfs_lookup_inode_ref(trans, root, path,
2804 dentry->d_name.name, dentry->d_name.len,
2811 if (check_path_shared(root, path))
2813 index = btrfs_inode_ref_index(path->nodes[0], ref);
2814 btrfs_release_path(path);
2817 * This is a commit root search, if we can lookup inode item and other
2818 * relative items in the commit root, it means the transaction of
2819 * dir/file creation has been committed, and the dir index item that we
2820 * delay to insert has also been inserted into the commit root. So
2821 * we needn't worry about the delayed insertion of the dir index item
2824 di = btrfs_lookup_dir_index_item(trans, root, path, dir_ino, index,
2825 dentry->d_name.name, dentry->d_name.len, 0);
2830 BUG_ON(ret == -ENOENT);
2831 if (check_path_shared(root, path))
2836 btrfs_free_path(path);
2837 /* Migrate the orphan reservation over */
2839 err = btrfs_block_rsv_migrate(trans->block_rsv,
2840 &root->fs_info->global_block_rsv,
2841 trans->bytes_reserved);
2844 btrfs_end_transaction(trans, root);
2845 root->fs_info->enospc_unlink = 0;
2846 return ERR_PTR(err);
2849 trans->block_rsv = &root->fs_info->global_block_rsv;
2853 static void __unlink_end_trans(struct btrfs_trans_handle *trans,
2854 struct btrfs_root *root)
2856 if (trans->block_rsv == &root->fs_info->global_block_rsv) {
2857 btrfs_block_rsv_release(root, trans->block_rsv,
2858 trans->bytes_reserved);
2859 trans->block_rsv = &root->fs_info->trans_block_rsv;
2860 BUG_ON(!root->fs_info->enospc_unlink);
2861 root->fs_info->enospc_unlink = 0;
2863 btrfs_end_transaction_throttle(trans, root);
2866 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
2868 struct btrfs_root *root = BTRFS_I(dir)->root;
2869 struct btrfs_trans_handle *trans;
2870 struct inode *inode = dentry->d_inode;
2872 unsigned long nr = 0;
2874 trans = __unlink_start_trans(dir, dentry);
2876 return PTR_ERR(trans);
2878 btrfs_record_unlink_dir(trans, dir, dentry->d_inode, 0);
2880 ret = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
2881 dentry->d_name.name, dentry->d_name.len);
2885 if (inode->i_nlink == 0) {
2886 ret = btrfs_orphan_add(trans, inode);
2892 nr = trans->blocks_used;
2893 __unlink_end_trans(trans, root);
2894 btrfs_btree_balance_dirty(root, nr);
2898 int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
2899 struct btrfs_root *root,
2900 struct inode *dir, u64 objectid,
2901 const char *name, int name_len)
2903 struct btrfs_path *path;
2904 struct extent_buffer *leaf;
2905 struct btrfs_dir_item *di;
2906 struct btrfs_key key;
2909 u64 dir_ino = btrfs_ino(dir);
2911 path = btrfs_alloc_path();
2915 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
2916 name, name_len, -1);
2917 BUG_ON(IS_ERR_OR_NULL(di));
2919 leaf = path->nodes[0];
2920 btrfs_dir_item_key_to_cpu(leaf, di, &key);
2921 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
2922 ret = btrfs_delete_one_dir_name(trans, root, path, di);
2924 btrfs_release_path(path);
2926 ret = btrfs_del_root_ref(trans, root->fs_info->tree_root,
2927 objectid, root->root_key.objectid,
2928 dir_ino, &index, name, name_len);
2930 BUG_ON(ret != -ENOENT);
2931 di = btrfs_search_dir_index_item(root, path, dir_ino,
2933 BUG_ON(IS_ERR_OR_NULL(di));
2935 leaf = path->nodes[0];
2936 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2937 btrfs_release_path(path);
2940 btrfs_release_path(path);
2942 ret = btrfs_delete_delayed_dir_index(trans, root, dir, index);
2945 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
2946 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
2947 ret = btrfs_update_inode(trans, root, dir);
2950 btrfs_free_path(path);
2954 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
2956 struct inode *inode = dentry->d_inode;
2958 struct btrfs_root *root = BTRFS_I(dir)->root;
2959 struct btrfs_trans_handle *trans;
2960 unsigned long nr = 0;
2962 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE ||
2963 btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID)
2966 trans = __unlink_start_trans(dir, dentry);
2968 return PTR_ERR(trans);
2970 if (unlikely(btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
2971 err = btrfs_unlink_subvol(trans, root, dir,
2972 BTRFS_I(inode)->location.objectid,
2973 dentry->d_name.name,
2974 dentry->d_name.len);
2978 err = btrfs_orphan_add(trans, inode);
2982 /* now the directory is empty */
2983 err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
2984 dentry->d_name.name, dentry->d_name.len);
2986 btrfs_i_size_write(inode, 0);
2988 nr = trans->blocks_used;
2989 __unlink_end_trans(trans, root);
2990 btrfs_btree_balance_dirty(root, nr);
2996 * this can truncate away extent items, csum items and directory items.
2997 * It starts at a high offset and removes keys until it can't find
2998 * any higher than new_size
3000 * csum items that cross the new i_size are truncated to the new size
3003 * min_type is the minimum key type to truncate down to. If set to 0, this
3004 * will kill all the items on this inode, including the INODE_ITEM_KEY.
3006 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
3007 struct btrfs_root *root,
3008 struct inode *inode,
3009 u64 new_size, u32 min_type)
3011 struct btrfs_path *path;
3012 struct extent_buffer *leaf;
3013 struct btrfs_file_extent_item *fi;
3014 struct btrfs_key key;
3015 struct btrfs_key found_key;
3016 u64 extent_start = 0;
3017 u64 extent_num_bytes = 0;
3018 u64 extent_offset = 0;
3020 u64 mask = root->sectorsize - 1;
3021 u32 found_type = (u8)-1;
3024 int pending_del_nr = 0;
3025 int pending_del_slot = 0;
3026 int extent_type = -1;
3030 u64 ino = btrfs_ino(inode);
3032 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
3034 path = btrfs_alloc_path();
3039 if (root->ref_cows || root == root->fs_info->tree_root)
3040 btrfs_drop_extent_cache(inode, new_size & (~mask), (u64)-1, 0);
3043 * This function is also used to drop the items in the log tree before
3044 * we relog the inode, so if root != BTRFS_I(inode)->root, it means
3045 * it is used to drop the loged items. So we shouldn't kill the delayed
3048 if (min_type == 0 && root == BTRFS_I(inode)->root)
3049 btrfs_kill_delayed_inode_items(inode);
3052 key.offset = (u64)-1;
3056 path->leave_spinning = 1;
3057 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3064 /* there are no items in the tree for us to truncate, we're
3067 if (path->slots[0] == 0)
3074 leaf = path->nodes[0];
3075 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3076 found_type = btrfs_key_type(&found_key);
3079 if (found_key.objectid != ino)
3082 if (found_type < min_type)
3085 item_end = found_key.offset;
3086 if (found_type == BTRFS_EXTENT_DATA_KEY) {
3087 fi = btrfs_item_ptr(leaf, path->slots[0],
3088 struct btrfs_file_extent_item);
3089 extent_type = btrfs_file_extent_type(leaf, fi);
3090 encoding = btrfs_file_extent_compression(leaf, fi);
3091 encoding |= btrfs_file_extent_encryption(leaf, fi);
3092 encoding |= btrfs_file_extent_other_encoding(leaf, fi);
3094 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
3096 btrfs_file_extent_num_bytes(leaf, fi);
3097 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
3098 item_end += btrfs_file_extent_inline_len(leaf,
3099 path->slots[0], fi);
3103 if (found_type > min_type) {
3106 if (item_end < new_size)
3108 if (found_key.offset >= new_size)
3114 /* FIXME, shrink the extent if the ref count is only 1 */
3115 if (found_type != BTRFS_EXTENT_DATA_KEY)
3118 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
3120 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
3121 if (!del_item && !encoding) {
3122 u64 orig_num_bytes =
3123 btrfs_file_extent_num_bytes(leaf, fi);
3124 extent_num_bytes = new_size -
3125 found_key.offset + root->sectorsize - 1;
3126 extent_num_bytes = extent_num_bytes &
3127 ~((u64)root->sectorsize - 1);
3128 btrfs_set_file_extent_num_bytes(leaf, fi,
3130 num_dec = (orig_num_bytes -
3132 if (root->ref_cows && extent_start != 0)
3133 inode_sub_bytes(inode, num_dec);
3134 btrfs_mark_buffer_dirty(leaf);
3137 btrfs_file_extent_disk_num_bytes(leaf,
3139 extent_offset = found_key.offset -
3140 btrfs_file_extent_offset(leaf, fi);
3142 /* FIXME blocksize != 4096 */
3143 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
3144 if (extent_start != 0) {
3147 inode_sub_bytes(inode, num_dec);
3150 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
3152 * we can't truncate inline items that have had
3156 btrfs_file_extent_compression(leaf, fi) == 0 &&
3157 btrfs_file_extent_encryption(leaf, fi) == 0 &&
3158 btrfs_file_extent_other_encoding(leaf, fi) == 0) {
3159 u32 size = new_size - found_key.offset;
3161 if (root->ref_cows) {
3162 inode_sub_bytes(inode, item_end + 1 -
3167 * update the ram bytes to properly reflect
3168 * the new size of our item
3170 btrfs_set_file_extent_ram_bytes(leaf, fi, size);
3172 btrfs_file_extent_calc_inline_size(size);
3173 ret = btrfs_truncate_item(trans, root, path,
3175 } else if (root->ref_cows) {
3176 inode_sub_bytes(inode, item_end + 1 -
3182 if (!pending_del_nr) {
3183 /* no pending yet, add ourselves */
3184 pending_del_slot = path->slots[0];
3186 } else if (pending_del_nr &&
3187 path->slots[0] + 1 == pending_del_slot) {
3188 /* hop on the pending chunk */
3190 pending_del_slot = path->slots[0];
3197 if (found_extent && (root->ref_cows ||
3198 root == root->fs_info->tree_root)) {
3199 btrfs_set_path_blocking(path);
3200 ret = btrfs_free_extent(trans, root, extent_start,
3201 extent_num_bytes, 0,
3202 btrfs_header_owner(leaf),
3203 ino, extent_offset);
3207 if (found_type == BTRFS_INODE_ITEM_KEY)
3210 if (path->slots[0] == 0 ||
3211 path->slots[0] != pending_del_slot) {
3212 if (root->ref_cows &&
3213 BTRFS_I(inode)->location.objectid !=
3214 BTRFS_FREE_INO_OBJECTID) {
3218 if (pending_del_nr) {
3219 ret = btrfs_del_items(trans, root, path,
3225 btrfs_release_path(path);
3232 if (pending_del_nr) {
3233 ret = btrfs_del_items(trans, root, path, pending_del_slot,
3237 btrfs_free_path(path);
3242 * taken from block_truncate_page, but does cow as it zeros out
3243 * any bytes left in the last page in the file.
3245 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
3247 struct inode *inode = mapping->host;
3248 struct btrfs_root *root = BTRFS_I(inode)->root;
3249 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3250 struct btrfs_ordered_extent *ordered;
3251 struct extent_state *cached_state = NULL;
3253 u32 blocksize = root->sectorsize;
3254 pgoff_t index = from >> PAGE_CACHE_SHIFT;
3255 unsigned offset = from & (PAGE_CACHE_SIZE-1);
3257 gfp_t mask = btrfs_alloc_write_mask(mapping);
3262 if ((offset & (blocksize - 1)) == 0)
3264 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
3270 page = find_or_create_page(mapping, index, mask);
3272 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
3276 page_start = page_offset(page);
3277 page_end = page_start + PAGE_CACHE_SIZE - 1;
3279 if (!PageUptodate(page)) {
3280 ret = btrfs_readpage(NULL, page);
3282 if (page->mapping != mapping) {
3284 page_cache_release(page);
3287 if (!PageUptodate(page)) {
3292 wait_on_page_writeback(page);
3294 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state,
3296 set_page_extent_mapped(page);
3298 ordered = btrfs_lookup_ordered_extent(inode, page_start);
3300 unlock_extent_cached(io_tree, page_start, page_end,
3301 &cached_state, GFP_NOFS);
3303 page_cache_release(page);
3304 btrfs_start_ordered_extent(inode, ordered, 1);
3305 btrfs_put_ordered_extent(ordered);
3309 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
3310 EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
3311 0, 0, &cached_state, GFP_NOFS);
3313 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
3316 unlock_extent_cached(io_tree, page_start, page_end,
3317 &cached_state, GFP_NOFS);
3322 if (offset != PAGE_CACHE_SIZE) {
3324 memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
3325 flush_dcache_page(page);
3328 ClearPageChecked(page);
3329 set_page_dirty(page);
3330 unlock_extent_cached(io_tree, page_start, page_end, &cached_state,
3335 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
3337 page_cache_release(page);
3343 * This function puts in dummy file extents for the area we're creating a hole
3344 * for. So if we are truncating this file to a larger size we need to insert
3345 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
3346 * the range between oldsize and size
3348 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
3350 struct btrfs_trans_handle *trans;
3351 struct btrfs_root *root = BTRFS_I(inode)->root;
3352 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3353 struct extent_map *em = NULL;
3354 struct extent_state *cached_state = NULL;
3355 u64 mask = root->sectorsize - 1;
3356 u64 hole_start = (oldsize + mask) & ~mask;
3357 u64 block_end = (size + mask) & ~mask;
3363 if (size <= hole_start)
3367 struct btrfs_ordered_extent *ordered;
3368 btrfs_wait_ordered_range(inode, hole_start,
3369 block_end - hole_start);
3370 lock_extent_bits(io_tree, hole_start, block_end - 1, 0,
3371 &cached_state, GFP_NOFS);
3372 ordered = btrfs_lookup_ordered_extent(inode, hole_start);
3375 unlock_extent_cached(io_tree, hole_start, block_end - 1,
3376 &cached_state, GFP_NOFS);
3377 btrfs_put_ordered_extent(ordered);
3380 cur_offset = hole_start;
3382 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
3383 block_end - cur_offset, 0);
3384 BUG_ON(IS_ERR_OR_NULL(em));
3385 last_byte = min(extent_map_end(em), block_end);
3386 last_byte = (last_byte + mask) & ~mask;
3387 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
3389 hole_size = last_byte - cur_offset;
3391 trans = btrfs_start_transaction(root, 3);
3392 if (IS_ERR(trans)) {
3393 err = PTR_ERR(trans);
3397 err = btrfs_drop_extents(trans, inode, cur_offset,
3398 cur_offset + hole_size,
3401 btrfs_update_inode(trans, root, inode);
3402 btrfs_end_transaction(trans, root);
3406 err = btrfs_insert_file_extent(trans, root,
3407 btrfs_ino(inode), cur_offset, 0,
3408 0, hole_size, 0, hole_size,
3411 btrfs_update_inode(trans, root, inode);
3412 btrfs_end_transaction(trans, root);
3416 btrfs_drop_extent_cache(inode, hole_start,
3419 btrfs_update_inode(trans, root, inode);
3420 btrfs_end_transaction(trans, root);
3422 free_extent_map(em);
3424 cur_offset = last_byte;
3425 if (cur_offset >= block_end)
3429 free_extent_map(em);
3430 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state,
3435 static int btrfs_setsize(struct inode *inode, loff_t newsize)
3437 struct btrfs_root *root = BTRFS_I(inode)->root;
3438 struct btrfs_trans_handle *trans;
3439 loff_t oldsize = i_size_read(inode);
3442 if (newsize == oldsize)
3445 if (newsize > oldsize) {
3446 truncate_pagecache(inode, oldsize, newsize);
3447 ret = btrfs_cont_expand(inode, oldsize, newsize);
3451 trans = btrfs_start_transaction(root, 1);
3453 return PTR_ERR(trans);
3455 i_size_write(inode, newsize);
3456 btrfs_ordered_update_i_size(inode, i_size_read(inode), NULL);
3457 ret = btrfs_update_inode(trans, root, inode);
3458 btrfs_end_transaction_throttle(trans, root);
3462 * We're truncating a file that used to have good data down to
3463 * zero. Make sure it gets into the ordered flush list so that
3464 * any new writes get down to disk quickly.
3467 BTRFS_I(inode)->ordered_data_close = 1;
3469 /* we don't support swapfiles, so vmtruncate shouldn't fail */
3470 truncate_setsize(inode, newsize);
3471 ret = btrfs_truncate(inode);
3477 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
3479 struct inode *inode = dentry->d_inode;
3480 struct btrfs_root *root = BTRFS_I(inode)->root;
3483 if (btrfs_root_readonly(root))
3486 err = inode_change_ok(inode, attr);
3490 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
3491 err = btrfs_setsize(inode, attr->ia_size);
3496 if (attr->ia_valid) {
3497 setattr_copy(inode, attr);
3498 err = btrfs_dirty_inode(inode);
3500 if (!err && attr->ia_valid & ATTR_MODE)
3501 err = btrfs_acl_chmod(inode);
3507 void btrfs_evict_inode(struct inode *inode)
3509 struct btrfs_trans_handle *trans;
3510 struct btrfs_root *root = BTRFS_I(inode)->root;
3511 struct btrfs_block_rsv *rsv, *global_rsv;
3512 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
3516 trace_btrfs_inode_evict(inode);
3518 truncate_inode_pages(&inode->i_data, 0);
3519 if (inode->i_nlink && (btrfs_root_refs(&root->root_item) != 0 ||
3520 btrfs_is_free_space_inode(root, inode)))
3523 if (is_bad_inode(inode)) {
3524 btrfs_orphan_del(NULL, inode);
3527 /* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */
3528 if (!special_file(inode->i_mode))
3529 btrfs_wait_ordered_range(inode, 0, (u64)-1);
3531 if (root->fs_info->log_root_recovering) {
3532 BUG_ON(!list_empty(&BTRFS_I(inode)->i_orphan));
3536 if (inode->i_nlink > 0) {
3537 BUG_ON(btrfs_root_refs(&root->root_item) != 0);
3541 rsv = btrfs_alloc_block_rsv(root);
3543 btrfs_orphan_del(NULL, inode);
3546 rsv->size = min_size;
3547 global_rsv = &root->fs_info->global_block_rsv;
3549 btrfs_i_size_write(inode, 0);
3552 * This is a bit simpler than btrfs_truncate since
3554 * 1) We've already reserved our space for our orphan item in the
3556 * 2) We're going to delete the inode item, so we don't need to update
3559 * So we just need to reserve some slack space in case we add bytes when
3560 * doing the truncate.
3563 ret = btrfs_block_rsv_refill_noflush(root, rsv, min_size);
3566 * Try and steal from the global reserve since we will
3567 * likely not use this space anyway, we want to try as
3568 * hard as possible to get this to work.
3571 ret = btrfs_block_rsv_migrate(global_rsv, rsv, min_size);
3574 printk(KERN_WARNING "Could not get space for a "
3575 "delete, will truncate on mount %d\n", ret);
3576 btrfs_orphan_del(NULL, inode);
3577 btrfs_free_block_rsv(root, rsv);
3581 trans = btrfs_start_transaction(root, 0);
3582 if (IS_ERR(trans)) {
3583 btrfs_orphan_del(NULL, inode);
3584 btrfs_free_block_rsv(root, rsv);
3588 trans->block_rsv = rsv;
3590 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
3594 nr = trans->blocks_used;
3595 btrfs_end_transaction(trans, root);
3597 btrfs_btree_balance_dirty(root, nr);
3600 btrfs_free_block_rsv(root, rsv);
3603 trans->block_rsv = root->orphan_block_rsv;
3604 ret = btrfs_orphan_del(trans, inode);
3608 trans->block_rsv = &root->fs_info->trans_block_rsv;
3609 if (!(root == root->fs_info->tree_root ||
3610 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
3611 btrfs_return_ino(root, btrfs_ino(inode));
3613 nr = trans->blocks_used;
3614 btrfs_end_transaction(trans, root);
3615 btrfs_btree_balance_dirty(root, nr);
3617 end_writeback(inode);
3622 * this returns the key found in the dir entry in the location pointer.
3623 * If no dir entries were found, location->objectid is 0.
3625 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
3626 struct btrfs_key *location)
3628 const char *name = dentry->d_name.name;
3629 int namelen = dentry->d_name.len;
3630 struct btrfs_dir_item *di;
3631 struct btrfs_path *path;
3632 struct btrfs_root *root = BTRFS_I(dir)->root;
3635 path = btrfs_alloc_path();
3639 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir), name,
3644 if (IS_ERR_OR_NULL(di))
3647 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
3649 btrfs_free_path(path);
3652 location->objectid = 0;
3657 * when we hit a tree root in a directory, the btrfs part of the inode
3658 * needs to be changed to reflect the root directory of the tree root. This
3659 * is kind of like crossing a mount point.
3661 static int fixup_tree_root_location(struct btrfs_root *root,
3663 struct dentry *dentry,
3664 struct btrfs_key *location,
3665 struct btrfs_root **sub_root)
3667 struct btrfs_path *path;
3668 struct btrfs_root *new_root;
3669 struct btrfs_root_ref *ref;
3670 struct extent_buffer *leaf;
3674 path = btrfs_alloc_path();
3681 ret = btrfs_find_root_ref(root->fs_info->tree_root, path,
3682 BTRFS_I(dir)->root->root_key.objectid,
3683 location->objectid);
3690 leaf = path->nodes[0];
3691 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
3692 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(dir) ||
3693 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
3696 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
3697 (unsigned long)(ref + 1),
3698 dentry->d_name.len);
3702 btrfs_release_path(path);
3704 new_root = btrfs_read_fs_root_no_name(root->fs_info, location);
3705 if (IS_ERR(new_root)) {
3706 err = PTR_ERR(new_root);
3710 if (btrfs_root_refs(&new_root->root_item) == 0) {
3715 *sub_root = new_root;
3716 location->objectid = btrfs_root_dirid(&new_root->root_item);
3717 location->type = BTRFS_INODE_ITEM_KEY;
3718 location->offset = 0;
3721 btrfs_free_path(path);
3725 static void inode_tree_add(struct inode *inode)
3727 struct btrfs_root *root = BTRFS_I(inode)->root;
3728 struct btrfs_inode *entry;
3730 struct rb_node *parent;
3731 u64 ino = btrfs_ino(inode);
3733 p = &root->inode_tree.rb_node;
3736 if (inode_unhashed(inode))
3739 spin_lock(&root->inode_lock);
3742 entry = rb_entry(parent, struct btrfs_inode, rb_node);
3744 if (ino < btrfs_ino(&entry->vfs_inode))
3745 p = &parent->rb_left;
3746 else if (ino > btrfs_ino(&entry->vfs_inode))
3747 p = &parent->rb_right;
3749 WARN_ON(!(entry->vfs_inode.i_state &
3750 (I_WILL_FREE | I_FREEING)));
3751 rb_erase(parent, &root->inode_tree);
3752 RB_CLEAR_NODE(parent);
3753 spin_unlock(&root->inode_lock);
3757 rb_link_node(&BTRFS_I(inode)->rb_node, parent, p);
3758 rb_insert_color(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3759 spin_unlock(&root->inode_lock);
3762 static void inode_tree_del(struct inode *inode)
3764 struct btrfs_root *root = BTRFS_I(inode)->root;
3767 spin_lock(&root->inode_lock);
3768 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
3769 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
3770 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
3771 empty = RB_EMPTY_ROOT(&root->inode_tree);
3773 spin_unlock(&root->inode_lock);
3776 * Free space cache has inodes in the tree root, but the tree root has a
3777 * root_refs of 0, so this could end up dropping the tree root as a
3778 * snapshot, so we need the extra !root->fs_info->tree_root check to
3779 * make sure we don't drop it.
3781 if (empty && btrfs_root_refs(&root->root_item) == 0 &&
3782 root != root->fs_info->tree_root) {
3783 synchronize_srcu(&root->fs_info->subvol_srcu);
3784 spin_lock(&root->inode_lock);
3785 empty = RB_EMPTY_ROOT(&root->inode_tree);
3786 spin_unlock(&root->inode_lock);
3788 btrfs_add_dead_root(root);
3792 int btrfs_invalidate_inodes(struct btrfs_root *root)
3794 struct rb_node *node;
3795 struct rb_node *prev;
3796 struct btrfs_inode *entry;
3797 struct inode *inode;
3800 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
3802 spin_lock(&root->inode_lock);
3804 node = root->inode_tree.rb_node;
3808 entry = rb_entry(node, struct btrfs_inode, rb_node);
3810 if (objectid < btrfs_ino(&entry->vfs_inode))
3811 node = node->rb_left;
3812 else if (objectid > btrfs_ino(&entry->vfs_inode))
3813 node = node->rb_right;
3819 entry = rb_entry(prev, struct btrfs_inode, rb_node);
3820 if (objectid <= btrfs_ino(&entry->vfs_inode)) {
3824 prev = rb_next(prev);
3828 entry = rb_entry(node, struct btrfs_inode, rb_node);
3829 objectid = btrfs_ino(&entry->vfs_inode) + 1;
3830 inode = igrab(&entry->vfs_inode);
3832 spin_unlock(&root->inode_lock);
3833 if (atomic_read(&inode->i_count) > 1)
3834 d_prune_aliases(inode);
3836 * btrfs_drop_inode will have it removed from
3837 * the inode cache when its usage count
3842 spin_lock(&root->inode_lock);
3846 if (cond_resched_lock(&root->inode_lock))
3849 node = rb_next(node);
3851 spin_unlock(&root->inode_lock);
3855 static int btrfs_init_locked_inode(struct inode *inode, void *p)
3857 struct btrfs_iget_args *args = p;
3858 inode->i_ino = args->location->objectid;
3859 memcpy(&BTRFS_I(inode)->location, args->location,
3860 sizeof(*args->location));
3861 BTRFS_I(inode)->root = args->root;
3862 btrfs_set_inode_space_info(args->root, inode);
3866 static int btrfs_find_actor(struct inode *inode, void *opaque)
3868 struct btrfs_iget_args *args = opaque;
3869 return args->location->objectid == BTRFS_I(inode)->location.objectid &&
3870 args->root == BTRFS_I(inode)->root;
3873 static struct inode *btrfs_iget_locked(struct super_block *s,
3874 struct btrfs_key *location,
3875 struct btrfs_root *root)
3877 struct inode *inode;
3878 struct btrfs_iget_args args;
3879 args.location = location;
3882 inode = iget5_locked(s, location->objectid, btrfs_find_actor,
3883 btrfs_init_locked_inode,
3888 /* Get an inode object given its location and corresponding root.
3889 * Returns in *is_new if the inode was read from disk
3891 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
3892 struct btrfs_root *root, int *new)
3894 struct inode *inode;
3896 inode = btrfs_iget_locked(s, location, root);
3898 return ERR_PTR(-ENOMEM);
3900 if (inode->i_state & I_NEW) {
3901 btrfs_read_locked_inode(inode);
3902 if (!is_bad_inode(inode)) {
3903 inode_tree_add(inode);
3904 unlock_new_inode(inode);
3908 unlock_new_inode(inode);
3910 inode = ERR_PTR(-ESTALE);
3917 static struct inode *new_simple_dir(struct super_block *s,
3918 struct btrfs_key *key,
3919 struct btrfs_root *root)
3921 struct inode *inode = new_inode(s);
3924 return ERR_PTR(-ENOMEM);
3926 BTRFS_I(inode)->root = root;
3927 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
3928 BTRFS_I(inode)->dummy_inode = 1;
3930 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
3931 inode->i_op = &simple_dir_inode_operations;
3932 inode->i_fop = &simple_dir_operations;
3933 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
3934 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
3939 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
3941 struct inode *inode;
3942 struct btrfs_root *root = BTRFS_I(dir)->root;
3943 struct btrfs_root *sub_root = root;
3944 struct btrfs_key location;
3948 if (dentry->d_name.len > BTRFS_NAME_LEN)
3949 return ERR_PTR(-ENAMETOOLONG);
3951 if (unlikely(d_need_lookup(dentry))) {
3952 memcpy(&location, dentry->d_fsdata, sizeof(struct btrfs_key));
3953 kfree(dentry->d_fsdata);
3954 dentry->d_fsdata = NULL;
3955 /* This thing is hashed, drop it for now */
3958 ret = btrfs_inode_by_name(dir, dentry, &location);
3962 return ERR_PTR(ret);
3964 if (location.objectid == 0)
3967 if (location.type == BTRFS_INODE_ITEM_KEY) {
3968 inode = btrfs_iget(dir->i_sb, &location, root, NULL);
3972 BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY);
3974 index = srcu_read_lock(&root->fs_info->subvol_srcu);
3975 ret = fixup_tree_root_location(root, dir, dentry,
3976 &location, &sub_root);
3979 inode = ERR_PTR(ret);
3981 inode = new_simple_dir(dir->i_sb, &location, sub_root);
3983 inode = btrfs_iget(dir->i_sb, &location, sub_root, NULL);
3985 srcu_read_unlock(&root->fs_info->subvol_srcu, index);
3987 if (!IS_ERR(inode) && root != sub_root) {
3988 down_read(&root->fs_info->cleanup_work_sem);
3989 if (!(inode->i_sb->s_flags & MS_RDONLY))
3990 ret = btrfs_orphan_cleanup(sub_root);
3991 up_read(&root->fs_info->cleanup_work_sem);
3993 inode = ERR_PTR(ret);
3999 static int btrfs_dentry_delete(const struct dentry *dentry)
4001 struct btrfs_root *root;
4003 if (!dentry->d_inode && !IS_ROOT(dentry))
4004 dentry = dentry->d_parent;
4006 if (dentry->d_inode) {
4007 root = BTRFS_I(dentry->d_inode)->root;
4008 if (btrfs_root_refs(&root->root_item) == 0)
4014 static void btrfs_dentry_release(struct dentry *dentry)
4016 if (dentry->d_fsdata)
4017 kfree(dentry->d_fsdata);
4020 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
4021 struct nameidata *nd)
4025 ret = d_splice_alias(btrfs_lookup_dentry(dir, dentry), dentry);
4026 if (unlikely(d_need_lookup(dentry))) {
4027 spin_lock(&dentry->d_lock);
4028 dentry->d_flags &= ~DCACHE_NEED_LOOKUP;
4029 spin_unlock(&dentry->d_lock);
4034 unsigned char btrfs_filetype_table[] = {
4035 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
4038 static int btrfs_real_readdir(struct file *filp, void *dirent,
4041 struct inode *inode = filp->f_dentry->d_inode;
4042 struct btrfs_root *root = BTRFS_I(inode)->root;
4043 struct btrfs_item *item;
4044 struct btrfs_dir_item *di;
4045 struct btrfs_key key;
4046 struct btrfs_key found_key;
4047 struct btrfs_path *path;
4048 struct list_head ins_list;
4049 struct list_head del_list;
4052 struct extent_buffer *leaf;
4054 unsigned char d_type;
4059 int key_type = BTRFS_DIR_INDEX_KEY;
4063 int is_curr = 0; /* filp->f_pos points to the current index? */
4065 /* FIXME, use a real flag for deciding about the key type */
4066 if (root->fs_info->tree_root == root)
4067 key_type = BTRFS_DIR_ITEM_KEY;
4069 /* special case for "." */
4070 if (filp->f_pos == 0) {
4071 over = filldir(dirent, ".", 1,
4072 filp->f_pos, btrfs_ino(inode), DT_DIR);
4077 /* special case for .., just use the back ref */
4078 if (filp->f_pos == 1) {
4079 u64 pino = parent_ino(filp->f_path.dentry);
4080 over = filldir(dirent, "..", 2,
4081 filp->f_pos, pino, DT_DIR);
4086 path = btrfs_alloc_path();
4092 if (key_type == BTRFS_DIR_INDEX_KEY) {
4093 INIT_LIST_HEAD(&ins_list);
4094 INIT_LIST_HEAD(&del_list);
4095 btrfs_get_delayed_items(inode, &ins_list, &del_list);
4098 btrfs_set_key_type(&key, key_type);
4099 key.offset = filp->f_pos;
4100 key.objectid = btrfs_ino(inode);
4102 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4107 leaf = path->nodes[0];
4108 slot = path->slots[0];
4109 if (slot >= btrfs_header_nritems(leaf)) {
4110 ret = btrfs_next_leaf(root, path);
4118 item = btrfs_item_nr(leaf, slot);
4119 btrfs_item_key_to_cpu(leaf, &found_key, slot);
4121 if (found_key.objectid != key.objectid)
4123 if (btrfs_key_type(&found_key) != key_type)
4125 if (found_key.offset < filp->f_pos)
4127 if (key_type == BTRFS_DIR_INDEX_KEY &&
4128 btrfs_should_delete_dir_index(&del_list,
4132 filp->f_pos = found_key.offset;
4135 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
4137 di_total = btrfs_item_size(leaf, item);
4139 while (di_cur < di_total) {
4140 struct btrfs_key location;
4143 if (verify_dir_item(root, leaf, di))
4146 name_len = btrfs_dir_name_len(leaf, di);
4147 if (name_len <= sizeof(tmp_name)) {
4148 name_ptr = tmp_name;
4150 name_ptr = kmalloc(name_len, GFP_NOFS);
4156 read_extent_buffer(leaf, name_ptr,
4157 (unsigned long)(di + 1), name_len);
4159 d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
4160 btrfs_dir_item_key_to_cpu(leaf, di, &location);
4164 q.hash = full_name_hash(q.name, q.len);
4165 tmp = d_lookup(filp->f_dentry, &q);
4167 struct btrfs_key *newkey;
4169 newkey = kzalloc(sizeof(struct btrfs_key),
4173 tmp = d_alloc(filp->f_dentry, &q);
4179 memcpy(newkey, &location,
4180 sizeof(struct btrfs_key));
4181 tmp->d_fsdata = newkey;
4182 tmp->d_flags |= DCACHE_NEED_LOOKUP;
4189 /* is this a reference to our own snapshot? If so
4192 if (location.type == BTRFS_ROOT_ITEM_KEY &&
4193 location.objectid == root->root_key.objectid) {
4197 over = filldir(dirent, name_ptr, name_len,
4198 found_key.offset, location.objectid,
4202 if (name_ptr != tmp_name)
4207 di_len = btrfs_dir_name_len(leaf, di) +
4208 btrfs_dir_data_len(leaf, di) + sizeof(*di);
4210 di = (struct btrfs_dir_item *)((char *)di + di_len);
4216 if (key_type == BTRFS_DIR_INDEX_KEY) {
4219 ret = btrfs_readdir_delayed_dir_index(filp, dirent, filldir,
4225 /* Reached end of directory/root. Bump pos past the last item. */
4226 if (key_type == BTRFS_DIR_INDEX_KEY)
4228 * 32-bit glibc will use getdents64, but then strtol -
4229 * so the last number we can serve is this.
4231 filp->f_pos = 0x7fffffff;
4237 if (key_type == BTRFS_DIR_INDEX_KEY)
4238 btrfs_put_delayed_items(&ins_list, &del_list);
4239 btrfs_free_path(path);
4243 int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc)
4245 struct btrfs_root *root = BTRFS_I(inode)->root;
4246 struct btrfs_trans_handle *trans;
4248 bool nolock = false;
4250 if (BTRFS_I(inode)->dummy_inode)
4253 if (btrfs_fs_closing(root->fs_info) && btrfs_is_free_space_inode(root, inode))
4256 if (wbc->sync_mode == WB_SYNC_ALL) {
4258 trans = btrfs_join_transaction_nolock(root);
4260 trans = btrfs_join_transaction(root);
4262 return PTR_ERR(trans);
4264 ret = btrfs_end_transaction_nolock(trans, root);
4266 ret = btrfs_commit_transaction(trans, root);
4272 * This is somewhat expensive, updating the tree every time the
4273 * inode changes. But, it is most likely to find the inode in cache.
4274 * FIXME, needs more benchmarking...there are no reasons other than performance
4275 * to keep or drop this code.
4277 int btrfs_dirty_inode(struct inode *inode)
4279 struct btrfs_root *root = BTRFS_I(inode)->root;
4280 struct btrfs_trans_handle *trans;
4283 if (BTRFS_I(inode)->dummy_inode)
4286 trans = btrfs_join_transaction(root);
4288 return PTR_ERR(trans);
4290 ret = btrfs_update_inode(trans, root, inode);
4291 if (ret && ret == -ENOSPC) {
4292 /* whoops, lets try again with the full transaction */
4293 btrfs_end_transaction(trans, root);
4294 trans = btrfs_start_transaction(root, 1);
4296 return PTR_ERR(trans);
4298 ret = btrfs_update_inode(trans, root, inode);
4300 btrfs_end_transaction(trans, root);
4301 if (BTRFS_I(inode)->delayed_node)
4302 btrfs_balance_delayed_items(root);
4308 * This is a copy of file_update_time. We need this so we can return error on
4309 * ENOSPC for updating the inode in the case of file write and mmap writes.
4311 int btrfs_update_time(struct file *file)
4313 struct inode *inode = file->f_path.dentry->d_inode;
4314 struct timespec now;
4316 enum { S_MTIME = 1, S_CTIME = 2, S_VERSION = 4 } sync_it = 0;
4318 /* First try to exhaust all avenues to not sync */
4319 if (IS_NOCMTIME(inode))
4322 now = current_fs_time(inode->i_sb);
4323 if (!timespec_equal(&inode->i_mtime, &now))
4326 if (!timespec_equal(&inode->i_ctime, &now))
4329 if (IS_I_VERSION(inode))
4330 sync_it |= S_VERSION;
4335 /* Finally allowed to write? Takes lock. */
4336 if (mnt_want_write_file(file))
4339 /* Only change inode inside the lock region */
4340 if (sync_it & S_VERSION)
4341 inode_inc_iversion(inode);
4342 if (sync_it & S_CTIME)
4343 inode->i_ctime = now;
4344 if (sync_it & S_MTIME)
4345 inode->i_mtime = now;
4346 ret = btrfs_dirty_inode(inode);
4348 mark_inode_dirty_sync(inode);
4349 mnt_drop_write(file->f_path.mnt);
4354 * find the highest existing sequence number in a directory
4355 * and then set the in-memory index_cnt variable to reflect
4356 * free sequence numbers
4358 static int btrfs_set_inode_index_count(struct inode *inode)
4360 struct btrfs_root *root = BTRFS_I(inode)->root;
4361 struct btrfs_key key, found_key;
4362 struct btrfs_path *path;
4363 struct extent_buffer *leaf;
4366 key.objectid = btrfs_ino(inode);
4367 btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
4368 key.offset = (u64)-1;
4370 path = btrfs_alloc_path();
4374 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4377 /* FIXME: we should be able to handle this */
4383 * MAGIC NUMBER EXPLANATION:
4384 * since we search a directory based on f_pos we have to start at 2
4385 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
4386 * else has to start at 2
4388 if (path->slots[0] == 0) {
4389 BTRFS_I(inode)->index_cnt = 2;
4395 leaf = path->nodes[0];
4396 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4398 if (found_key.objectid != btrfs_ino(inode) ||
4399 btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
4400 BTRFS_I(inode)->index_cnt = 2;
4404 BTRFS_I(inode)->index_cnt = found_key.offset + 1;
4406 btrfs_free_path(path);
4411 * helper to find a free sequence number in a given directory. This current
4412 * code is very simple, later versions will do smarter things in the btree
4414 int btrfs_set_inode_index(struct inode *dir, u64 *index)
4418 if (BTRFS_I(dir)->index_cnt == (u64)-1) {
4419 ret = btrfs_inode_delayed_dir_index_count(dir);
4421 ret = btrfs_set_inode_index_count(dir);
4427 *index = BTRFS_I(dir)->index_cnt;
4428 BTRFS_I(dir)->index_cnt++;
4433 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
4434 struct btrfs_root *root,
4436 const char *name, int name_len,
4437 u64 ref_objectid, u64 objectid, int mode,
4440 struct inode *inode;
4441 struct btrfs_inode_item *inode_item;
4442 struct btrfs_key *location;
4443 struct btrfs_path *path;
4444 struct btrfs_inode_ref *ref;
4445 struct btrfs_key key[2];
4451 path = btrfs_alloc_path();
4453 return ERR_PTR(-ENOMEM);
4455 inode = new_inode(root->fs_info->sb);
4457 btrfs_free_path(path);
4458 return ERR_PTR(-ENOMEM);
4462 * we have to initialize this early, so we can reclaim the inode
4463 * number if we fail afterwards in this function.
4465 inode->i_ino = objectid;
4468 trace_btrfs_inode_request(dir);
4470 ret = btrfs_set_inode_index(dir, index);
4472 btrfs_free_path(path);
4474 return ERR_PTR(ret);
4478 * index_cnt is ignored for everything but a dir,
4479 * btrfs_get_inode_index_count has an explanation for the magic
4482 BTRFS_I(inode)->index_cnt = 2;
4483 BTRFS_I(inode)->root = root;
4484 BTRFS_I(inode)->generation = trans->transid;
4485 inode->i_generation = BTRFS_I(inode)->generation;
4486 btrfs_set_inode_space_info(root, inode);
4493 key[0].objectid = objectid;
4494 btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
4497 key[1].objectid = objectid;
4498 btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
4499 key[1].offset = ref_objectid;
4501 sizes[0] = sizeof(struct btrfs_inode_item);
4502 sizes[1] = name_len + sizeof(*ref);
4504 path->leave_spinning = 1;
4505 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
4509 inode_init_owner(inode, dir, mode);
4510 inode_set_bytes(inode, 0);
4511 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
4512 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
4513 struct btrfs_inode_item);
4514 fill_inode_item(trans, path->nodes[0], inode_item, inode);
4516 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
4517 struct btrfs_inode_ref);
4518 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
4519 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
4520 ptr = (unsigned long)(ref + 1);
4521 write_extent_buffer(path->nodes[0], name, ptr, name_len);
4523 btrfs_mark_buffer_dirty(path->nodes[0]);
4524 btrfs_free_path(path);
4526 location = &BTRFS_I(inode)->location;
4527 location->objectid = objectid;
4528 location->offset = 0;
4529 btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
4531 btrfs_inherit_iflags(inode, dir);
4533 if (S_ISREG(mode)) {
4534 if (btrfs_test_opt(root, NODATASUM))
4535 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
4536 if (btrfs_test_opt(root, NODATACOW) ||
4537 (BTRFS_I(dir)->flags & BTRFS_INODE_NODATACOW))
4538 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
4541 insert_inode_hash(inode);
4542 inode_tree_add(inode);
4544 trace_btrfs_inode_new(inode);
4545 btrfs_set_inode_last_trans(trans, inode);
4550 BTRFS_I(dir)->index_cnt--;
4551 btrfs_free_path(path);
4553 return ERR_PTR(ret);
4556 static inline u8 btrfs_inode_type(struct inode *inode)
4558 return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
4562 * utility function to add 'inode' into 'parent_inode' with
4563 * a give name and a given sequence number.
4564 * if 'add_backref' is true, also insert a backref from the
4565 * inode to the parent directory.
4567 int btrfs_add_link(struct btrfs_trans_handle *trans,
4568 struct inode *parent_inode, struct inode *inode,
4569 const char *name, int name_len, int add_backref, u64 index)
4572 struct btrfs_key key;
4573 struct btrfs_root *root = BTRFS_I(parent_inode)->root;
4574 u64 ino = btrfs_ino(inode);
4575 u64 parent_ino = btrfs_ino(parent_inode);
4577 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
4578 memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key));
4581 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
4585 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
4586 ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
4587 key.objectid, root->root_key.objectid,
4588 parent_ino, index, name, name_len);
4589 } else if (add_backref) {
4590 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino,
4595 ret = btrfs_insert_dir_item(trans, root, name, name_len,
4597 btrfs_inode_type(inode), index);
4600 btrfs_i_size_write(parent_inode, parent_inode->i_size +
4602 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
4603 ret = btrfs_update_inode(trans, root, parent_inode);
4608 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
4609 struct inode *dir, struct dentry *dentry,
4610 struct inode *inode, int backref, u64 index)
4612 int err = btrfs_add_link(trans, dir, inode,
4613 dentry->d_name.name, dentry->d_name.len,
4620 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
4621 int mode, dev_t rdev)
4623 struct btrfs_trans_handle *trans;
4624 struct btrfs_root *root = BTRFS_I(dir)->root;
4625 struct inode *inode = NULL;
4629 unsigned long nr = 0;
4632 if (!new_valid_dev(rdev))
4636 * 2 for inode item and ref
4638 * 1 for xattr if selinux is on
4640 trans = btrfs_start_transaction(root, 5);
4642 return PTR_ERR(trans);
4644 err = btrfs_find_free_ino(root, &objectid);
4648 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4649 dentry->d_name.len, btrfs_ino(dir), objectid,
4651 if (IS_ERR(inode)) {
4652 err = PTR_ERR(inode);
4656 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4663 * If the active LSM wants to access the inode during
4664 * d_instantiate it needs these. Smack checks to see
4665 * if the filesystem supports xattrs by looking at the
4669 inode->i_op = &btrfs_special_inode_operations;
4670 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
4674 init_special_inode(inode, inode->i_mode, rdev);
4675 btrfs_update_inode(trans, root, inode);
4676 d_instantiate(dentry, inode);
4679 nr = trans->blocks_used;
4680 btrfs_end_transaction_throttle(trans, root);
4681 btrfs_btree_balance_dirty(root, nr);
4683 inode_dec_link_count(inode);
4689 static int btrfs_create(struct inode *dir, struct dentry *dentry,
4690 int mode, struct nameidata *nd)
4692 struct btrfs_trans_handle *trans;
4693 struct btrfs_root *root = BTRFS_I(dir)->root;
4694 struct inode *inode = NULL;
4697 unsigned long nr = 0;
4702 * 2 for inode item and ref
4704 * 1 for xattr if selinux is on
4706 trans = btrfs_start_transaction(root, 5);
4708 return PTR_ERR(trans);
4710 err = btrfs_find_free_ino(root, &objectid);
4714 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4715 dentry->d_name.len, btrfs_ino(dir), objectid,
4717 if (IS_ERR(inode)) {
4718 err = PTR_ERR(inode);
4722 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4729 * If the active LSM wants to access the inode during
4730 * d_instantiate it needs these. Smack checks to see
4731 * if the filesystem supports xattrs by looking at the
4734 inode->i_fop = &btrfs_file_operations;
4735 inode->i_op = &btrfs_file_inode_operations;
4737 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
4741 inode->i_mapping->a_ops = &btrfs_aops;
4742 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
4743 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
4744 d_instantiate(dentry, inode);
4747 nr = trans->blocks_used;
4748 btrfs_end_transaction_throttle(trans, root);
4750 inode_dec_link_count(inode);
4753 btrfs_btree_balance_dirty(root, nr);
4757 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
4758 struct dentry *dentry)
4760 struct btrfs_trans_handle *trans;
4761 struct btrfs_root *root = BTRFS_I(dir)->root;
4762 struct inode *inode = old_dentry->d_inode;
4764 unsigned long nr = 0;
4768 /* do not allow sys_link's with other subvols of the same device */
4769 if (root->objectid != BTRFS_I(inode)->root->objectid)
4772 if (inode->i_nlink == ~0U)
4775 err = btrfs_set_inode_index(dir, &index);
4780 * 2 items for inode and inode ref
4781 * 2 items for dir items
4782 * 1 item for parent inode
4784 trans = btrfs_start_transaction(root, 5);
4785 if (IS_ERR(trans)) {
4786 err = PTR_ERR(trans);
4790 btrfs_inc_nlink(inode);
4791 inode->i_ctime = CURRENT_TIME;
4794 err = btrfs_add_nondir(trans, dir, dentry, inode, 1, index);
4799 struct dentry *parent = dentry->d_parent;
4800 err = btrfs_update_inode(trans, root, inode);
4802 d_instantiate(dentry, inode);
4803 btrfs_log_new_name(trans, inode, NULL, parent);
4806 nr = trans->blocks_used;
4807 btrfs_end_transaction_throttle(trans, root);
4810 inode_dec_link_count(inode);
4813 btrfs_btree_balance_dirty(root, nr);
4817 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
4819 struct inode *inode = NULL;
4820 struct btrfs_trans_handle *trans;
4821 struct btrfs_root *root = BTRFS_I(dir)->root;
4823 int drop_on_err = 0;
4826 unsigned long nr = 1;
4829 * 2 items for inode and ref
4830 * 2 items for dir items
4831 * 1 for xattr if selinux is on
4833 trans = btrfs_start_transaction(root, 5);
4835 return PTR_ERR(trans);
4837 err = btrfs_find_free_ino(root, &objectid);
4841 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
4842 dentry->d_name.len, btrfs_ino(dir), objectid,
4843 S_IFDIR | mode, &index);
4844 if (IS_ERR(inode)) {
4845 err = PTR_ERR(inode);
4851 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
4855 inode->i_op = &btrfs_dir_inode_operations;
4856 inode->i_fop = &btrfs_dir_file_operations;
4858 btrfs_i_size_write(inode, 0);
4859 err = btrfs_update_inode(trans, root, inode);
4863 err = btrfs_add_link(trans, dir, inode, dentry->d_name.name,
4864 dentry->d_name.len, 0, index);
4868 d_instantiate(dentry, inode);
4872 nr = trans->blocks_used;
4873 btrfs_end_transaction_throttle(trans, root);
4876 btrfs_btree_balance_dirty(root, nr);
4880 /* helper for btfs_get_extent. Given an existing extent in the tree,
4881 * and an extent that you want to insert, deal with overlap and insert
4882 * the new extent into the tree.
4884 static int merge_extent_mapping(struct extent_map_tree *em_tree,
4885 struct extent_map *existing,
4886 struct extent_map *em,
4887 u64 map_start, u64 map_len)
4891 BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
4892 start_diff = map_start - em->start;
4893 em->start = map_start;
4895 if (em->block_start < EXTENT_MAP_LAST_BYTE &&
4896 !test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
4897 em->block_start += start_diff;
4898 em->block_len -= start_diff;
4900 return add_extent_mapping(em_tree, em);
4903 static noinline int uncompress_inline(struct btrfs_path *path,
4904 struct inode *inode, struct page *page,
4905 size_t pg_offset, u64 extent_offset,
4906 struct btrfs_file_extent_item *item)
4909 struct extent_buffer *leaf = path->nodes[0];
4912 unsigned long inline_size;
4916 WARN_ON(pg_offset != 0);
4917 compress_type = btrfs_file_extent_compression(leaf, item);
4918 max_size = btrfs_file_extent_ram_bytes(leaf, item);
4919 inline_size = btrfs_file_extent_inline_item_len(leaf,
4920 btrfs_item_nr(leaf, path->slots[0]));
4921 tmp = kmalloc(inline_size, GFP_NOFS);
4924 ptr = btrfs_file_extent_inline_start(item);
4926 read_extent_buffer(leaf, tmp, ptr, inline_size);
4928 max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size);
4929 ret = btrfs_decompress(compress_type, tmp, page,
4930 extent_offset, inline_size, max_size);
4932 char *kaddr = kmap_atomic(page, KM_USER0);
4933 unsigned long copy_size = min_t(u64,
4934 PAGE_CACHE_SIZE - pg_offset,
4935 max_size - extent_offset);
4936 memset(kaddr + pg_offset, 0, copy_size);
4937 kunmap_atomic(kaddr, KM_USER0);
4944 * a bit scary, this does extent mapping from logical file offset to the disk.
4945 * the ugly parts come from merging extents from the disk with the in-ram
4946 * representation. This gets more complex because of the data=ordered code,
4947 * where the in-ram extents might be locked pending data=ordered completion.
4949 * This also copies inline extents directly into the page.
4952 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
4953 size_t pg_offset, u64 start, u64 len,
4959 u64 extent_start = 0;
4961 u64 objectid = btrfs_ino(inode);
4963 struct btrfs_path *path = NULL;
4964 struct btrfs_root *root = BTRFS_I(inode)->root;
4965 struct btrfs_file_extent_item *item;
4966 struct extent_buffer *leaf;
4967 struct btrfs_key found_key;
4968 struct extent_map *em = NULL;
4969 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
4970 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4971 struct btrfs_trans_handle *trans = NULL;
4975 read_lock(&em_tree->lock);
4976 em = lookup_extent_mapping(em_tree, start, len);
4978 em->bdev = root->fs_info->fs_devices->latest_bdev;
4979 read_unlock(&em_tree->lock);
4982 if (em->start > start || em->start + em->len <= start)
4983 free_extent_map(em);
4984 else if (em->block_start == EXTENT_MAP_INLINE && page)
4985 free_extent_map(em);
4989 em = alloc_extent_map();
4994 em->bdev = root->fs_info->fs_devices->latest_bdev;
4995 em->start = EXTENT_MAP_HOLE;
4996 em->orig_start = EXTENT_MAP_HOLE;
4998 em->block_len = (u64)-1;
5001 path = btrfs_alloc_path();
5007 * Chances are we'll be called again, so go ahead and do
5013 ret = btrfs_lookup_file_extent(trans, root, path,
5014 objectid, start, trans != NULL);
5021 if (path->slots[0] == 0)
5026 leaf = path->nodes[0];
5027 item = btrfs_item_ptr(leaf, path->slots[0],
5028 struct btrfs_file_extent_item);
5029 /* are we inside the extent that was found? */
5030 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5031 found_type = btrfs_key_type(&found_key);
5032 if (found_key.objectid != objectid ||
5033 found_type != BTRFS_EXTENT_DATA_KEY) {
5037 found_type = btrfs_file_extent_type(leaf, item);
5038 extent_start = found_key.offset;
5039 compress_type = btrfs_file_extent_compression(leaf, item);
5040 if (found_type == BTRFS_FILE_EXTENT_REG ||
5041 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
5042 extent_end = extent_start +
5043 btrfs_file_extent_num_bytes(leaf, item);
5044 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
5046 size = btrfs_file_extent_inline_len(leaf, path->slots[0], item);
5047 extent_end = (extent_start + size + root->sectorsize - 1) &
5048 ~((u64)root->sectorsize - 1);
5051 if (start >= extent_end) {
5053 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
5054 ret = btrfs_next_leaf(root, path);
5061 leaf = path->nodes[0];
5063 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5064 if (found_key.objectid != objectid ||
5065 found_key.type != BTRFS_EXTENT_DATA_KEY)
5067 if (start + len <= found_key.offset)
5070 em->len = found_key.offset - start;
5074 if (found_type == BTRFS_FILE_EXTENT_REG ||
5075 found_type == BTRFS_FILE_EXTENT_PREALLOC) {
5076 em->start = extent_start;
5077 em->len = extent_end - extent_start;
5078 em->orig_start = extent_start -
5079 btrfs_file_extent_offset(leaf, item);
5080 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
5082 em->block_start = EXTENT_MAP_HOLE;
5085 if (compress_type != BTRFS_COMPRESS_NONE) {
5086 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
5087 em->compress_type = compress_type;
5088 em->block_start = bytenr;
5089 em->block_len = btrfs_file_extent_disk_num_bytes(leaf,
5092 bytenr += btrfs_file_extent_offset(leaf, item);
5093 em->block_start = bytenr;
5094 em->block_len = em->len;
5095 if (found_type == BTRFS_FILE_EXTENT_PREALLOC)
5096 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
5099 } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
5103 size_t extent_offset;
5106 em->block_start = EXTENT_MAP_INLINE;
5107 if (!page || create) {
5108 em->start = extent_start;
5109 em->len = extent_end - extent_start;
5113 size = btrfs_file_extent_inline_len(leaf, path->slots[0], item);
5114 extent_offset = page_offset(page) + pg_offset - extent_start;
5115 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
5116 size - extent_offset);
5117 em->start = extent_start + extent_offset;
5118 em->len = (copy_size + root->sectorsize - 1) &
5119 ~((u64)root->sectorsize - 1);
5120 em->orig_start = EXTENT_MAP_INLINE;
5121 if (compress_type) {
5122 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
5123 em->compress_type = compress_type;
5125 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
5126 if (create == 0 && !PageUptodate(page)) {
5127 if (btrfs_file_extent_compression(leaf, item) !=
5128 BTRFS_COMPRESS_NONE) {
5129 ret = uncompress_inline(path, inode, page,
5131 extent_offset, item);
5135 read_extent_buffer(leaf, map + pg_offset, ptr,
5137 if (pg_offset + copy_size < PAGE_CACHE_SIZE) {
5138 memset(map + pg_offset + copy_size, 0,
5139 PAGE_CACHE_SIZE - pg_offset -
5144 flush_dcache_page(page);
5145 } else if (create && PageUptodate(page)) {
5149 free_extent_map(em);
5152 btrfs_release_path(path);
5153 trans = btrfs_join_transaction(root);
5156 return ERR_CAST(trans);
5160 write_extent_buffer(leaf, map + pg_offset, ptr,
5163 btrfs_mark_buffer_dirty(leaf);
5165 set_extent_uptodate(io_tree, em->start,
5166 extent_map_end(em) - 1, NULL, GFP_NOFS);
5169 printk(KERN_ERR "btrfs unknown found_type %d\n", found_type);
5176 em->block_start = EXTENT_MAP_HOLE;
5177 set_bit(EXTENT_FLAG_VACANCY, &em->flags);
5179 btrfs_release_path(path);
5180 if (em->start > start || extent_map_end(em) <= start) {
5181 printk(KERN_ERR "Btrfs: bad extent! em: [%llu %llu] passed "
5182 "[%llu %llu]\n", (unsigned long long)em->start,
5183 (unsigned long long)em->len,
5184 (unsigned long long)start,
5185 (unsigned long long)len);
5191 write_lock(&em_tree->lock);
5192 ret = add_extent_mapping(em_tree, em);
5193 /* it is possible that someone inserted the extent into the tree
5194 * while we had the lock dropped. It is also possible that
5195 * an overlapping map exists in the tree
5197 if (ret == -EEXIST) {
5198 struct extent_map *existing;
5202 existing = lookup_extent_mapping(em_tree, start, len);
5203 if (existing && (existing->start > start ||
5204 existing->start + existing->len <= start)) {
5205 free_extent_map(existing);
5209 existing = lookup_extent_mapping(em_tree, em->start,
5212 err = merge_extent_mapping(em_tree, existing,
5215 free_extent_map(existing);
5217 free_extent_map(em);
5222 free_extent_map(em);
5226 free_extent_map(em);
5231 write_unlock(&em_tree->lock);
5234 trace_btrfs_get_extent(root, em);
5237 btrfs_free_path(path);
5239 ret = btrfs_end_transaction(trans, root);
5244 free_extent_map(em);
5245 return ERR_PTR(err);
5250 struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page,
5251 size_t pg_offset, u64 start, u64 len,
5254 struct extent_map *em;
5255 struct extent_map *hole_em = NULL;
5256 u64 range_start = start;
5262 em = btrfs_get_extent(inode, page, pg_offset, start, len, create);
5267 * if our em maps to a hole, there might
5268 * actually be delalloc bytes behind it
5270 if (em->block_start != EXTENT_MAP_HOLE)
5276 /* check to see if we've wrapped (len == -1 or similar) */
5285 /* ok, we didn't find anything, lets look for delalloc */
5286 found = count_range_bits(&BTRFS_I(inode)->io_tree, &range_start,
5287 end, len, EXTENT_DELALLOC, 1);
5288 found_end = range_start + found;
5289 if (found_end < range_start)
5290 found_end = (u64)-1;
5293 * we didn't find anything useful, return
5294 * the original results from get_extent()
5296 if (range_start > end || found_end <= start) {
5302 /* adjust the range_start to make sure it doesn't
5303 * go backwards from the start they passed in
5305 range_start = max(start,range_start);
5306 found = found_end - range_start;
5309 u64 hole_start = start;
5312 em = alloc_extent_map();
5318 * when btrfs_get_extent can't find anything it
5319 * returns one huge hole
5321 * make sure what it found really fits our range, and
5322 * adjust to make sure it is based on the start from
5326 u64 calc_end = extent_map_end(hole_em);
5328 if (calc_end <= start || (hole_em->start > end)) {
5329 free_extent_map(hole_em);
5332 hole_start = max(hole_em->start, start);
5333 hole_len = calc_end - hole_start;
5337 if (hole_em && range_start > hole_start) {
5338 /* our hole starts before our delalloc, so we
5339 * have to return just the parts of the hole
5340 * that go until the delalloc starts
5342 em->len = min(hole_len,
5343 range_start - hole_start);
5344 em->start = hole_start;
5345 em->orig_start = hole_start;
5347 * don't adjust block start at all,
5348 * it is fixed at EXTENT_MAP_HOLE
5350 em->block_start = hole_em->block_start;
5351 em->block_len = hole_len;
5353 em->start = range_start;
5355 em->orig_start = range_start;
5356 em->block_start = EXTENT_MAP_DELALLOC;
5357 em->block_len = found;
5359 } else if (hole_em) {
5364 free_extent_map(hole_em);
5366 free_extent_map(em);
5367 return ERR_PTR(err);
5372 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
5373 struct extent_map *em,
5376 struct btrfs_root *root = BTRFS_I(inode)->root;
5377 struct btrfs_trans_handle *trans;
5378 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
5379 struct btrfs_key ins;
5382 bool insert = false;
5385 * Ok if the extent map we looked up is a hole and is for the exact
5386 * range we want, there is no reason to allocate a new one, however if
5387 * it is not right then we need to free this one and drop the cache for
5390 if (em->block_start != EXTENT_MAP_HOLE || em->start != start ||
5392 free_extent_map(em);
5395 btrfs_drop_extent_cache(inode, start, start + len - 1, 0);
5398 trans = btrfs_join_transaction(root);
5400 return ERR_CAST(trans);
5402 if (start <= BTRFS_I(inode)->disk_i_size && len < 64 * 1024)
5403 btrfs_add_inode_defrag(trans, inode);
5405 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
5407 alloc_hint = get_extent_allocation_hint(inode, start, len);
5408 ret = btrfs_reserve_extent(trans, root, len, root->sectorsize, 0,
5409 alloc_hint, (u64)-1, &ins, 1);
5416 em = alloc_extent_map();
5418 em = ERR_PTR(-ENOMEM);
5424 em->orig_start = em->start;
5425 em->len = ins.offset;
5427 em->block_start = ins.objectid;
5428 em->block_len = ins.offset;
5429 em->bdev = root->fs_info->fs_devices->latest_bdev;
5432 * We need to do this because if we're using the original em we searched
5433 * for, we could have EXTENT_FLAG_VACANCY set, and we don't want that.
5436 set_bit(EXTENT_FLAG_PINNED, &em->flags);
5439 write_lock(&em_tree->lock);
5440 ret = add_extent_mapping(em_tree, em);
5441 write_unlock(&em_tree->lock);
5444 btrfs_drop_extent_cache(inode, start, start + em->len - 1, 0);
5447 ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
5448 ins.offset, ins.offset, 0);
5450 btrfs_free_reserved_extent(root, ins.objectid, ins.offset);
5454 btrfs_end_transaction(trans, root);
5459 * returns 1 when the nocow is safe, < 1 on error, 0 if the
5460 * block must be cow'd
5462 static noinline int can_nocow_odirect(struct btrfs_trans_handle *trans,
5463 struct inode *inode, u64 offset, u64 len)
5465 struct btrfs_path *path;
5467 struct extent_buffer *leaf;
5468 struct btrfs_root *root = BTRFS_I(inode)->root;
5469 struct btrfs_file_extent_item *fi;
5470 struct btrfs_key key;
5478 path = btrfs_alloc_path();
5482 ret = btrfs_lookup_file_extent(trans, root, path, btrfs_ino(inode),
5487 slot = path->slots[0];
5490 /* can't find the item, must cow */
5497 leaf = path->nodes[0];
5498 btrfs_item_key_to_cpu(leaf, &key, slot);
5499 if (key.objectid != btrfs_ino(inode) ||
5500 key.type != BTRFS_EXTENT_DATA_KEY) {
5501 /* not our file or wrong item type, must cow */
5505 if (key.offset > offset) {
5506 /* Wrong offset, must cow */
5510 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
5511 found_type = btrfs_file_extent_type(leaf, fi);
5512 if (found_type != BTRFS_FILE_EXTENT_REG &&
5513 found_type != BTRFS_FILE_EXTENT_PREALLOC) {
5514 /* not a regular extent, must cow */
5517 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
5518 backref_offset = btrfs_file_extent_offset(leaf, fi);
5520 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
5521 if (extent_end < offset + len) {
5522 /* extent doesn't include our full range, must cow */
5526 if (btrfs_extent_readonly(root, disk_bytenr))
5530 * look for other files referencing this extent, if we
5531 * find any we must cow
5533 if (btrfs_cross_ref_exist(trans, root, btrfs_ino(inode),
5534 key.offset - backref_offset, disk_bytenr))
5538 * adjust disk_bytenr and num_bytes to cover just the bytes
5539 * in this extent we are about to write. If there
5540 * are any csums in that range we have to cow in order
5541 * to keep the csums correct
5543 disk_bytenr += backref_offset;
5544 disk_bytenr += offset - key.offset;
5545 num_bytes = min(offset + len, extent_end) - offset;
5546 if (csum_exist_in_range(root, disk_bytenr, num_bytes))
5549 * all of the above have passed, it is safe to overwrite this extent
5554 btrfs_free_path(path);
5558 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
5559 struct buffer_head *bh_result, int create)
5561 struct extent_map *em;
5562 struct btrfs_root *root = BTRFS_I(inode)->root;
5563 u64 start = iblock << inode->i_blkbits;
5564 u64 len = bh_result->b_size;
5565 struct btrfs_trans_handle *trans;
5567 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
5572 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered
5573 * io. INLINE is special, and we could probably kludge it in here, but
5574 * it's still buffered so for safety lets just fall back to the generic
5577 * For COMPRESSED we _have_ to read the entire extent in so we can
5578 * decompress it, so there will be buffering required no matter what we
5579 * do, so go ahead and fallback to buffered.
5581 * We return -ENOTBLK because thats what makes DIO go ahead and go back
5582 * to buffered IO. Don't blame me, this is the price we pay for using
5585 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
5586 em->block_start == EXTENT_MAP_INLINE) {
5587 free_extent_map(em);
5591 /* Just a good old fashioned hole, return */
5592 if (!create && (em->block_start == EXTENT_MAP_HOLE ||
5593 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
5594 free_extent_map(em);
5595 /* DIO will do one hole at a time, so just unlock a sector */
5596 unlock_extent(&BTRFS_I(inode)->io_tree, start,
5597 start + root->sectorsize - 1, GFP_NOFS);
5602 * We don't allocate a new extent in the following cases
5604 * 1) The inode is marked as NODATACOW. In this case we'll just use the
5606 * 2) The extent is marked as PREALLOC. We're good to go here and can
5607 * just use the extent.
5611 len = em->len - (start - em->start);
5615 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
5616 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
5617 em->block_start != EXTENT_MAP_HOLE)) {
5622 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
5623 type = BTRFS_ORDERED_PREALLOC;
5625 type = BTRFS_ORDERED_NOCOW;
5626 len = min(len, em->len - (start - em->start));
5627 block_start = em->block_start + (start - em->start);
5630 * we're not going to log anything, but we do need
5631 * to make sure the current transaction stays open
5632 * while we look for nocow cross refs
5634 trans = btrfs_join_transaction(root);
5638 if (can_nocow_odirect(trans, inode, start, len) == 1) {
5639 ret = btrfs_add_ordered_extent_dio(inode, start,
5640 block_start, len, len, type);
5641 btrfs_end_transaction(trans, root);
5643 free_extent_map(em);
5648 btrfs_end_transaction(trans, root);
5652 * this will cow the extent, reset the len in case we changed
5655 len = bh_result->b_size;
5656 em = btrfs_new_extent_direct(inode, em, start, len);
5659 len = min(len, em->len - (start - em->start));
5661 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, start + len - 1,
5662 EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DIRTY, 1,
5665 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
5667 bh_result->b_size = len;
5668 bh_result->b_bdev = em->bdev;
5669 set_buffer_mapped(bh_result);
5670 if (create && !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
5671 set_buffer_new(bh_result);
5673 free_extent_map(em);
5678 struct btrfs_dio_private {
5679 struct inode *inode;
5686 /* number of bios pending for this dio */
5687 atomic_t pending_bios;
5692 struct bio *orig_bio;
5695 static void btrfs_endio_direct_read(struct bio *bio, int err)
5697 struct btrfs_dio_private *dip = bio->bi_private;
5698 struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
5699 struct bio_vec *bvec = bio->bi_io_vec;
5700 struct inode *inode = dip->inode;
5701 struct btrfs_root *root = BTRFS_I(inode)->root;
5703 u32 *private = dip->csums;
5705 start = dip->logical_offset;
5707 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
5708 struct page *page = bvec->bv_page;
5711 unsigned long flags;
5713 local_irq_save(flags);
5714 kaddr = kmap_atomic(page, KM_IRQ0);
5715 csum = btrfs_csum_data(root, kaddr + bvec->bv_offset,
5716 csum, bvec->bv_len);
5717 btrfs_csum_final(csum, (char *)&csum);
5718 kunmap_atomic(kaddr, KM_IRQ0);
5719 local_irq_restore(flags);
5721 flush_dcache_page(bvec->bv_page);
5722 if (csum != *private) {
5723 printk(KERN_ERR "btrfs csum failed ino %llu off"
5724 " %llu csum %u private %u\n",
5725 (unsigned long long)btrfs_ino(inode),
5726 (unsigned long long)start,
5732 start += bvec->bv_len;
5735 } while (bvec <= bvec_end);
5737 unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
5738 dip->logical_offset + dip->bytes - 1, GFP_NOFS);
5739 bio->bi_private = dip->private;
5744 /* If we had a csum failure make sure to clear the uptodate flag */
5746 clear_bit(BIO_UPTODATE, &bio->bi_flags);
5747 dio_end_io(bio, err);
5750 static void btrfs_endio_direct_write(struct bio *bio, int err)
5752 struct btrfs_dio_private *dip = bio->bi_private;
5753 struct inode *inode = dip->inode;
5754 struct btrfs_root *root = BTRFS_I(inode)->root;
5755 struct btrfs_trans_handle *trans;
5756 struct btrfs_ordered_extent *ordered = NULL;
5757 struct extent_state *cached_state = NULL;
5758 u64 ordered_offset = dip->logical_offset;
5759 u64 ordered_bytes = dip->bytes;
5765 ret = btrfs_dec_test_first_ordered_pending(inode, &ordered,
5773 trans = btrfs_join_transaction(root);
5774 if (IS_ERR(trans)) {
5778 trans->block_rsv = &root->fs_info->delalloc_block_rsv;
5780 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags)) {
5781 ret = btrfs_ordered_update_i_size(inode, 0, ordered);
5783 err = btrfs_update_inode_fallback(trans, root, inode);
5787 lock_extent_bits(&BTRFS_I(inode)->io_tree, ordered->file_offset,
5788 ordered->file_offset + ordered->len - 1, 0,
5789 &cached_state, GFP_NOFS);
5791 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags)) {
5792 ret = btrfs_mark_extent_written(trans, inode,
5793 ordered->file_offset,
5794 ordered->file_offset +
5801 ret = insert_reserved_file_extent(trans, inode,
5802 ordered->file_offset,
5808 BTRFS_FILE_EXTENT_REG);
5809 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
5810 ordered->file_offset, ordered->len);
5818 add_pending_csums(trans, inode, ordered->file_offset, &ordered->list);
5819 ret = btrfs_ordered_update_i_size(inode, 0, ordered);
5820 if (!ret || !test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags))
5821 btrfs_update_inode_fallback(trans, root, inode);
5824 unlock_extent_cached(&BTRFS_I(inode)->io_tree, ordered->file_offset,
5825 ordered->file_offset + ordered->len - 1,
5826 &cached_state, GFP_NOFS);
5828 btrfs_delalloc_release_metadata(inode, ordered->len);
5829 btrfs_end_transaction(trans, root);
5830 ordered_offset = ordered->file_offset + ordered->len;
5831 btrfs_put_ordered_extent(ordered);
5832 btrfs_put_ordered_extent(ordered);
5836 * our bio might span multiple ordered extents. If we haven't
5837 * completed the accounting for the whole dio, go back and try again
5839 if (ordered_offset < dip->logical_offset + dip->bytes) {
5840 ordered_bytes = dip->logical_offset + dip->bytes -
5845 bio->bi_private = dip->private;
5850 /* If we had an error make sure to clear the uptodate flag */
5852 clear_bit(BIO_UPTODATE, &bio->bi_flags);
5853 dio_end_io(bio, err);
5856 static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw,
5857 struct bio *bio, int mirror_num,
5858 unsigned long bio_flags, u64 offset)
5861 struct btrfs_root *root = BTRFS_I(inode)->root;
5862 ret = btrfs_csum_one_bio(root, inode, bio, offset, 1);
5867 static void btrfs_end_dio_bio(struct bio *bio, int err)
5869 struct btrfs_dio_private *dip = bio->bi_private;
5872 printk(KERN_ERR "btrfs direct IO failed ino %llu rw %lu "
5873 "sector %#Lx len %u err no %d\n",
5874 (unsigned long long)btrfs_ino(dip->inode), bio->bi_rw,
5875 (unsigned long long)bio->bi_sector, bio->bi_size, err);
5879 * before atomic variable goto zero, we must make sure
5880 * dip->errors is perceived to be set.
5882 smp_mb__before_atomic_dec();
5885 /* if there are more bios still pending for this dio, just exit */
5886 if (!atomic_dec_and_test(&dip->pending_bios))
5890 bio_io_error(dip->orig_bio);
5892 set_bit(BIO_UPTODATE, &dip->orig_bio->bi_flags);
5893 bio_endio(dip->orig_bio, 0);
5899 static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev,
5900 u64 first_sector, gfp_t gfp_flags)
5902 int nr_vecs = bio_get_nr_vecs(bdev);
5903 return btrfs_bio_alloc(bdev, first_sector, nr_vecs, gfp_flags);
5906 static inline int __btrfs_submit_dio_bio(struct bio *bio, struct inode *inode,
5907 int rw, u64 file_offset, int skip_sum,
5908 u32 *csums, int async_submit)
5910 int write = rw & REQ_WRITE;
5911 struct btrfs_root *root = BTRFS_I(inode)->root;
5915 ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
5922 if (write && async_submit) {
5923 ret = btrfs_wq_submit_bio(root->fs_info,
5924 inode, rw, bio, 0, 0,
5926 __btrfs_submit_bio_start_direct_io,
5927 __btrfs_submit_bio_done);
5931 * If we aren't doing async submit, calculate the csum of the
5934 ret = btrfs_csum_one_bio(root, inode, bio, file_offset, 1);
5937 } else if (!skip_sum) {
5938 ret = btrfs_lookup_bio_sums_dio(root, inode, bio,
5939 file_offset, csums);
5945 ret = btrfs_map_bio(root, rw, bio, 0, async_submit);
5951 static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip,
5954 struct inode *inode = dip->inode;
5955 struct btrfs_root *root = BTRFS_I(inode)->root;
5956 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
5958 struct bio *orig_bio = dip->orig_bio;
5959 struct bio_vec *bvec = orig_bio->bi_io_vec;
5960 u64 start_sector = orig_bio->bi_sector;
5961 u64 file_offset = dip->logical_offset;
5965 u32 *csums = dip->csums;
5967 int async_submit = 0;
5968 int write = rw & REQ_WRITE;
5970 map_length = orig_bio->bi_size;
5971 ret = btrfs_map_block(map_tree, READ, start_sector << 9,
5972 &map_length, NULL, 0);
5978 if (map_length >= orig_bio->bi_size) {
5984 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev, start_sector, GFP_NOFS);
5987 bio->bi_private = dip;
5988 bio->bi_end_io = btrfs_end_dio_bio;
5989 atomic_inc(&dip->pending_bios);
5991 while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) {
5992 if (unlikely(map_length < submit_len + bvec->bv_len ||
5993 bio_add_page(bio, bvec->bv_page, bvec->bv_len,
5994 bvec->bv_offset) < bvec->bv_len)) {
5996 * inc the count before we submit the bio so
5997 * we know the end IO handler won't happen before
5998 * we inc the count. Otherwise, the dip might get freed
5999 * before we're done setting it up
6001 atomic_inc(&dip->pending_bios);
6002 ret = __btrfs_submit_dio_bio(bio, inode, rw,
6003 file_offset, skip_sum,
6004 csums, async_submit);
6007 atomic_dec(&dip->pending_bios);
6011 /* Write's use the ordered csums */
6012 if (!write && !skip_sum)
6013 csums = csums + nr_pages;
6014 start_sector += submit_len >> 9;
6015 file_offset += submit_len;
6020 bio = btrfs_dio_bio_alloc(orig_bio->bi_bdev,
6021 start_sector, GFP_NOFS);
6024 bio->bi_private = dip;
6025 bio->bi_end_io = btrfs_end_dio_bio;
6027 map_length = orig_bio->bi_size;
6028 ret = btrfs_map_block(map_tree, READ, start_sector << 9,
6029 &map_length, NULL, 0);
6035 submit_len += bvec->bv_len;
6042 ret = __btrfs_submit_dio_bio(bio, inode, rw, file_offset, skip_sum,
6043 csums, async_submit);
6051 * before atomic variable goto zero, we must
6052 * make sure dip->errors is perceived to be set.
6054 smp_mb__before_atomic_dec();
6055 if (atomic_dec_and_test(&dip->pending_bios))
6056 bio_io_error(dip->orig_bio);
6058 /* bio_end_io() will handle error, so we needn't return it */
6062 static void btrfs_submit_direct(int rw, struct bio *bio, struct inode *inode,
6065 struct btrfs_root *root = BTRFS_I(inode)->root;
6066 struct btrfs_dio_private *dip;
6067 struct bio_vec *bvec = bio->bi_io_vec;
6069 int write = rw & REQ_WRITE;
6072 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
6074 dip = kmalloc(sizeof(*dip), GFP_NOFS);
6081 /* Write's use the ordered csum stuff, so we don't need dip->csums */
6082 if (!write && !skip_sum) {
6083 dip->csums = kmalloc(sizeof(u32) * bio->bi_vcnt, GFP_NOFS);
6091 dip->private = bio->bi_private;
6093 dip->logical_offset = file_offset;
6097 dip->bytes += bvec->bv_len;
6099 } while (bvec <= (bio->bi_io_vec + bio->bi_vcnt - 1));
6101 dip->disk_bytenr = (u64)bio->bi_sector << 9;
6102 bio->bi_private = dip;
6104 dip->orig_bio = bio;
6105 atomic_set(&dip->pending_bios, 0);
6108 bio->bi_end_io = btrfs_endio_direct_write;
6110 bio->bi_end_io = btrfs_endio_direct_read;
6112 ret = btrfs_submit_direct_hook(rw, dip, skip_sum);
6117 * If this is a write, we need to clean up the reserved space and kill
6118 * the ordered extent.
6121 struct btrfs_ordered_extent *ordered;
6122 ordered = btrfs_lookup_ordered_extent(inode, file_offset);
6123 if (!test_bit(BTRFS_ORDERED_PREALLOC, &ordered->flags) &&
6124 !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags))
6125 btrfs_free_reserved_extent(root, ordered->start,
6127 btrfs_put_ordered_extent(ordered);
6128 btrfs_put_ordered_extent(ordered);
6130 bio_endio(bio, ret);
6133 static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb,
6134 const struct iovec *iov, loff_t offset,
6135 unsigned long nr_segs)
6141 unsigned blocksize_mask = root->sectorsize - 1;
6142 ssize_t retval = -EINVAL;
6143 loff_t end = offset;
6145 if (offset & blocksize_mask)
6148 /* Check the memory alignment. Blocks cannot straddle pages */
6149 for (seg = 0; seg < nr_segs; seg++) {
6150 addr = (unsigned long)iov[seg].iov_base;
6151 size = iov[seg].iov_len;
6153 if ((addr & blocksize_mask) || (size & blocksize_mask))
6156 /* If this is a write we don't need to check anymore */
6161 * Check to make sure we don't have duplicate iov_base's in this
6162 * iovec, if so return EINVAL, otherwise we'll get csum errors
6163 * when reading back.
6165 for (i = seg + 1; i < nr_segs; i++) {
6166 if (iov[seg].iov_base == iov[i].iov_base)
6174 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
6175 const struct iovec *iov, loff_t offset,
6176 unsigned long nr_segs)
6178 struct file *file = iocb->ki_filp;
6179 struct inode *inode = file->f_mapping->host;
6180 struct btrfs_ordered_extent *ordered;
6181 struct extent_state *cached_state = NULL;
6182 u64 lockstart, lockend;
6184 int writing = rw & WRITE;
6186 size_t count = iov_length(iov, nr_segs);
6188 if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov,
6194 lockend = offset + count - 1;
6197 ret = btrfs_delalloc_reserve_space(inode, count);
6203 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6204 0, &cached_state, GFP_NOFS);
6206 * We're concerned with the entire range that we're going to be
6207 * doing DIO to, so we need to make sure theres no ordered
6208 * extents in this range.
6210 ordered = btrfs_lookup_ordered_range(inode, lockstart,
6211 lockend - lockstart + 1);
6214 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6215 &cached_state, GFP_NOFS);
6216 btrfs_start_ordered_extent(inode, ordered, 1);
6217 btrfs_put_ordered_extent(ordered);
6222 * we don't use btrfs_set_extent_delalloc because we don't want
6223 * the dirty or uptodate bits
6226 write_bits = EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING;
6227 ret = set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
6228 EXTENT_DELALLOC, 0, NULL, &cached_state,
6231 clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
6232 lockend, EXTENT_LOCKED | write_bits,
6233 1, 0, &cached_state, GFP_NOFS);
6238 free_extent_state(cached_state);
6239 cached_state = NULL;
6241 ret = __blockdev_direct_IO(rw, iocb, inode,
6242 BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev,
6243 iov, offset, nr_segs, btrfs_get_blocks_direct, NULL,
6244 btrfs_submit_direct, 0);
6246 if (ret < 0 && ret != -EIOCBQUEUED) {
6247 clear_extent_bit(&BTRFS_I(inode)->io_tree, offset,
6248 offset + iov_length(iov, nr_segs) - 1,
6249 EXTENT_LOCKED | write_bits, 1, 0,
6250 &cached_state, GFP_NOFS);
6251 } else if (ret >= 0 && ret < iov_length(iov, nr_segs)) {
6253 * We're falling back to buffered, unlock the section we didn't
6256 clear_extent_bit(&BTRFS_I(inode)->io_tree, offset + ret,
6257 offset + iov_length(iov, nr_segs) - 1,
6258 EXTENT_LOCKED | write_bits, 1, 0,
6259 &cached_state, GFP_NOFS);
6262 free_extent_state(cached_state);
6266 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
6267 __u64 start, __u64 len)
6269 return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap);
6272 int btrfs_readpage(struct file *file, struct page *page)
6274 struct extent_io_tree *tree;
6275 tree = &BTRFS_I(page->mapping->host)->io_tree;
6276 return extent_read_full_page(tree, page, btrfs_get_extent, 0);
6279 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
6281 struct extent_io_tree *tree;
6284 if (current->flags & PF_MEMALLOC) {
6285 redirty_page_for_writepage(wbc, page);
6289 tree = &BTRFS_I(page->mapping->host)->io_tree;
6290 return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
6293 int btrfs_writepages(struct address_space *mapping,
6294 struct writeback_control *wbc)
6296 struct extent_io_tree *tree;
6298 tree = &BTRFS_I(mapping->host)->io_tree;
6299 return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
6303 btrfs_readpages(struct file *file, struct address_space *mapping,
6304 struct list_head *pages, unsigned nr_pages)
6306 struct extent_io_tree *tree;
6307 tree = &BTRFS_I(mapping->host)->io_tree;
6308 return extent_readpages(tree, mapping, pages, nr_pages,
6311 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
6313 struct extent_io_tree *tree;
6314 struct extent_map_tree *map;
6317 tree = &BTRFS_I(page->mapping->host)->io_tree;
6318 map = &BTRFS_I(page->mapping->host)->extent_tree;
6319 ret = try_release_extent_mapping(map, tree, page, gfp_flags);
6321 ClearPagePrivate(page);
6322 set_page_private(page, 0);
6323 page_cache_release(page);
6328 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
6330 if (PageWriteback(page) || PageDirty(page))
6332 return __btrfs_releasepage(page, gfp_flags & GFP_NOFS);
6335 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
6337 struct extent_io_tree *tree;
6338 struct btrfs_ordered_extent *ordered;
6339 struct extent_state *cached_state = NULL;
6340 u64 page_start = page_offset(page);
6341 u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
6345 * we have the page locked, so new writeback can't start,
6346 * and the dirty bit won't be cleared while we are here.
6348 * Wait for IO on this page so that we can safely clear
6349 * the PagePrivate2 bit and do ordered accounting
6351 wait_on_page_writeback(page);
6353 tree = &BTRFS_I(page->mapping->host)->io_tree;
6355 btrfs_releasepage(page, GFP_NOFS);
6358 lock_extent_bits(tree, page_start, page_end, 0, &cached_state,
6360 ordered = btrfs_lookup_ordered_extent(page->mapping->host,
6364 * IO on this page will never be started, so we need
6365 * to account for any ordered extents now
6367 clear_extent_bit(tree, page_start, page_end,
6368 EXTENT_DIRTY | EXTENT_DELALLOC |
6369 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING, 1, 0,
6370 &cached_state, GFP_NOFS);
6372 * whoever cleared the private bit is responsible
6373 * for the finish_ordered_io
6375 if (TestClearPagePrivate2(page)) {
6376 btrfs_finish_ordered_io(page->mapping->host,
6377 page_start, page_end);
6379 btrfs_put_ordered_extent(ordered);
6380 cached_state = NULL;
6381 lock_extent_bits(tree, page_start, page_end, 0, &cached_state,
6384 clear_extent_bit(tree, page_start, page_end,
6385 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
6386 EXTENT_DO_ACCOUNTING, 1, 1, &cached_state, GFP_NOFS);
6387 __btrfs_releasepage(page, GFP_NOFS);
6389 ClearPageChecked(page);
6390 if (PagePrivate(page)) {
6391 ClearPagePrivate(page);
6392 set_page_private(page, 0);
6393 page_cache_release(page);
6398 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
6399 * called from a page fault handler when a page is first dirtied. Hence we must
6400 * be careful to check for EOF conditions here. We set the page up correctly
6401 * for a written page which means we get ENOSPC checking when writing into
6402 * holes and correct delalloc and unwritten extent mapping on filesystems that
6403 * support these features.
6405 * We are not allowed to take the i_mutex here so we have to play games to
6406 * protect against truncate races as the page could now be beyond EOF. Because
6407 * vmtruncate() writes the inode size before removing pages, once we have the
6408 * page lock we can determine safely if the page is beyond EOF. If it is not
6409 * beyond EOF, then the page is guaranteed safe against truncation until we
6412 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
6414 struct page *page = vmf->page;
6415 struct inode *inode = fdentry(vma->vm_file)->d_inode;
6416 struct btrfs_root *root = BTRFS_I(inode)->root;
6417 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6418 struct btrfs_ordered_extent *ordered;
6419 struct extent_state *cached_state = NULL;
6421 unsigned long zero_start;
6427 /* Need this to keep space reservations serialized */
6428 mutex_lock(&inode->i_mutex);
6429 ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
6430 mutex_unlock(&inode->i_mutex);
6432 ret = btrfs_update_time(vma->vm_file);
6436 else /* -ENOSPC, -EIO, etc */
6437 ret = VM_FAULT_SIGBUS;
6441 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
6444 size = i_size_read(inode);
6445 page_start = page_offset(page);
6446 page_end = page_start + PAGE_CACHE_SIZE - 1;
6448 if ((page->mapping != inode->i_mapping) ||
6449 (page_start >= size)) {
6450 /* page got truncated out from underneath us */
6453 wait_on_page_writeback(page);
6455 lock_extent_bits(io_tree, page_start, page_end, 0, &cached_state,
6457 set_page_extent_mapped(page);
6460 * we can't set the delalloc bits if there are pending ordered
6461 * extents. Drop our locks and wait for them to finish
6463 ordered = btrfs_lookup_ordered_extent(inode, page_start);
6465 unlock_extent_cached(io_tree, page_start, page_end,
6466 &cached_state, GFP_NOFS);
6468 btrfs_start_ordered_extent(inode, ordered, 1);
6469 btrfs_put_ordered_extent(ordered);
6474 * XXX - page_mkwrite gets called every time the page is dirtied, even
6475 * if it was already dirty, so for space accounting reasons we need to
6476 * clear any delalloc bits for the range we are fixing to save. There
6477 * is probably a better way to do this, but for now keep consistent with
6478 * prepare_pages in the normal write path.
6480 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
6481 EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
6482 0, 0, &cached_state, GFP_NOFS);
6484 ret = btrfs_set_extent_delalloc(inode, page_start, page_end,
6487 unlock_extent_cached(io_tree, page_start, page_end,
6488 &cached_state, GFP_NOFS);
6489 ret = VM_FAULT_SIGBUS;
6494 /* page is wholly or partially inside EOF */
6495 if (page_start + PAGE_CACHE_SIZE > size)
6496 zero_start = size & ~PAGE_CACHE_MASK;
6498 zero_start = PAGE_CACHE_SIZE;
6500 if (zero_start != PAGE_CACHE_SIZE) {
6502 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
6503 flush_dcache_page(page);
6506 ClearPageChecked(page);
6507 set_page_dirty(page);
6508 SetPageUptodate(page);
6510 BTRFS_I(inode)->last_trans = root->fs_info->generation;
6511 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
6513 unlock_extent_cached(io_tree, page_start, page_end, &cached_state, GFP_NOFS);
6517 return VM_FAULT_LOCKED;
6519 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
6524 static int btrfs_truncate(struct inode *inode)
6526 struct btrfs_root *root = BTRFS_I(inode)->root;
6527 struct btrfs_block_rsv *rsv;
6530 struct btrfs_trans_handle *trans;
6532 u64 mask = root->sectorsize - 1;
6533 u64 min_size = btrfs_calc_trunc_metadata_size(root, 1);
6535 ret = btrfs_truncate_page(inode->i_mapping, inode->i_size);
6539 btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
6540 btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
6543 * Yes ladies and gentelment, this is indeed ugly. The fact is we have
6544 * 3 things going on here
6546 * 1) We need to reserve space for our orphan item and the space to
6547 * delete our orphan item. Lord knows we don't want to have a dangling
6548 * orphan item because we didn't reserve space to remove it.
6550 * 2) We need to reserve space to update our inode.
6552 * 3) We need to have something to cache all the space that is going to
6553 * be free'd up by the truncate operation, but also have some slack
6554 * space reserved in case it uses space during the truncate (thank you
6555 * very much snapshotting).
6557 * And we need these to all be seperate. The fact is we can use alot of
6558 * space doing the truncate, and we have no earthly idea how much space
6559 * we will use, so we need the truncate reservation to be seperate so it
6560 * doesn't end up using space reserved for updating the inode or
6561 * removing the orphan item. We also need to be able to stop the
6562 * transaction and start a new one, which means we need to be able to
6563 * update the inode several times, and we have no idea of knowing how
6564 * many times that will be, so we can't just reserve 1 item for the
6565 * entirety of the opration, so that has to be done seperately as well.
6566 * Then there is the orphan item, which does indeed need to be held on
6567 * to for the whole operation, and we need nobody to touch this reserved
6568 * space except the orphan code.
6570 * So that leaves us with
6572 * 1) root->orphan_block_rsv - for the orphan deletion.
6573 * 2) rsv - for the truncate reservation, which we will steal from the
6574 * transaction reservation.
6575 * 3) fs_info->trans_block_rsv - this will have 1 items worth left for
6576 * updating the inode.
6578 rsv = btrfs_alloc_block_rsv(root);
6581 rsv->size = min_size;
6584 * 1 for the truncate slack space
6585 * 1 for the orphan item we're going to add
6586 * 1 for the orphan item deletion
6587 * 1 for updating the inode.
6589 trans = btrfs_start_transaction(root, 4);
6590 if (IS_ERR(trans)) {
6591 err = PTR_ERR(trans);
6595 /* Migrate the slack space for the truncate to our reserve */
6596 ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv,
6600 ret = btrfs_orphan_add(trans, inode);
6602 btrfs_end_transaction(trans, root);
6607 * setattr is responsible for setting the ordered_data_close flag,
6608 * but that is only tested during the last file release. That
6609 * could happen well after the next commit, leaving a great big
6610 * window where new writes may get lost if someone chooses to write
6611 * to this file after truncating to zero
6613 * The inode doesn't have any dirty data here, and so if we commit
6614 * this is a noop. If someone immediately starts writing to the inode
6615 * it is very likely we'll catch some of their writes in this
6616 * transaction, and the commit will find this file on the ordered
6617 * data list with good things to send down.
6619 * This is a best effort solution, there is still a window where
6620 * using truncate to replace the contents of the file will
6621 * end up with a zero length file after a crash.
6623 if (inode->i_size == 0 && BTRFS_I(inode)->ordered_data_close)
6624 btrfs_add_ordered_operation(trans, root, inode);
6627 ret = btrfs_block_rsv_refill(root, rsv, min_size);
6630 * This can only happen with the original transaction we
6631 * started above, every other time we shouldn't have a
6632 * transaction started yet.
6641 /* Just need the 1 for updating the inode */
6642 trans = btrfs_start_transaction(root, 1);
6643 if (IS_ERR(trans)) {
6644 ret = err = PTR_ERR(trans);
6650 trans->block_rsv = rsv;
6652 ret = btrfs_truncate_inode_items(trans, root, inode,
6654 BTRFS_EXTENT_DATA_KEY);
6655 if (ret != -EAGAIN) {
6660 trans->block_rsv = &root->fs_info->trans_block_rsv;
6661 ret = btrfs_update_inode(trans, root, inode);
6667 nr = trans->blocks_used;
6668 btrfs_end_transaction(trans, root);
6670 btrfs_btree_balance_dirty(root, nr);
6673 if (ret == 0 && inode->i_nlink > 0) {
6674 trans->block_rsv = root->orphan_block_rsv;
6675 ret = btrfs_orphan_del(trans, inode);
6678 } else if (ret && inode->i_nlink > 0) {
6680 * Failed to do the truncate, remove us from the in memory
6683 ret = btrfs_orphan_del(NULL, inode);
6687 trans->block_rsv = &root->fs_info->trans_block_rsv;
6688 ret = btrfs_update_inode(trans, root, inode);
6692 nr = trans->blocks_used;
6693 ret = btrfs_end_transaction_throttle(trans, root);
6694 btrfs_btree_balance_dirty(root, nr);
6698 btrfs_free_block_rsv(root, rsv);
6707 * create a new subvolume directory/inode (helper for the ioctl).
6709 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
6710 struct btrfs_root *new_root, u64 new_dirid)
6712 struct inode *inode;
6716 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid,
6717 new_dirid, S_IFDIR | 0700, &index);
6719 return PTR_ERR(inode);
6720 inode->i_op = &btrfs_dir_inode_operations;
6721 inode->i_fop = &btrfs_dir_file_operations;
6723 set_nlink(inode, 1);
6724 btrfs_i_size_write(inode, 0);
6726 err = btrfs_update_inode(trans, new_root, inode);
6733 struct inode *btrfs_alloc_inode(struct super_block *sb)
6735 struct btrfs_inode *ei;
6736 struct inode *inode;
6738 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
6743 ei->space_info = NULL;
6747 ei->last_sub_trans = 0;
6748 ei->logged_trans = 0;
6749 ei->delalloc_bytes = 0;
6750 ei->disk_i_size = 0;
6753 ei->index_cnt = (u64)-1;
6754 ei->last_unlink_trans = 0;
6756 spin_lock_init(&ei->lock);
6757 ei->outstanding_extents = 0;
6758 ei->reserved_extents = 0;
6760 ei->ordered_data_close = 0;
6761 ei->orphan_meta_reserved = 0;
6762 ei->dummy_inode = 0;
6764 ei->delalloc_meta_reserved = 0;
6765 ei->force_compress = BTRFS_COMPRESS_NONE;
6767 ei->delayed_node = NULL;
6769 inode = &ei->vfs_inode;
6770 extent_map_tree_init(&ei->extent_tree);
6771 extent_io_tree_init(&ei->io_tree, &inode->i_data);
6772 extent_io_tree_init(&ei->io_failure_tree, &inode->i_data);
6773 mutex_init(&ei->log_mutex);
6774 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
6775 INIT_LIST_HEAD(&ei->i_orphan);
6776 INIT_LIST_HEAD(&ei->delalloc_inodes);
6777 INIT_LIST_HEAD(&ei->ordered_operations);
6778 RB_CLEAR_NODE(&ei->rb_node);
6783 static void btrfs_i_callback(struct rcu_head *head)
6785 struct inode *inode = container_of(head, struct inode, i_rcu);
6786 INIT_LIST_HEAD(&inode->i_dentry);
6787 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
6790 void btrfs_destroy_inode(struct inode *inode)
6792 struct btrfs_ordered_extent *ordered;
6793 struct btrfs_root *root = BTRFS_I(inode)->root;
6795 WARN_ON(!list_empty(&inode->i_dentry));
6796 WARN_ON(inode->i_data.nrpages);
6797 WARN_ON(BTRFS_I(inode)->outstanding_extents);
6798 WARN_ON(BTRFS_I(inode)->reserved_extents);
6799 WARN_ON(BTRFS_I(inode)->delalloc_bytes);
6800 WARN_ON(BTRFS_I(inode)->csum_bytes);
6803 * This can happen where we create an inode, but somebody else also
6804 * created the same inode and we need to destroy the one we already
6811 * Make sure we're properly removed from the ordered operation
6815 if (!list_empty(&BTRFS_I(inode)->ordered_operations)) {
6816 spin_lock(&root->fs_info->ordered_extent_lock);
6817 list_del_init(&BTRFS_I(inode)->ordered_operations);
6818 spin_unlock(&root->fs_info->ordered_extent_lock);
6821 spin_lock(&root->orphan_lock);
6822 if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
6823 printk(KERN_INFO "BTRFS: inode %llu still on the orphan list\n",
6824 (unsigned long long)btrfs_ino(inode));
6825 list_del_init(&BTRFS_I(inode)->i_orphan);
6827 spin_unlock(&root->orphan_lock);
6830 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
6834 printk(KERN_ERR "btrfs found ordered "
6835 "extent %llu %llu on inode cleanup\n",
6836 (unsigned long long)ordered->file_offset,
6837 (unsigned long long)ordered->len);
6838 btrfs_remove_ordered_extent(inode, ordered);
6839 btrfs_put_ordered_extent(ordered);
6840 btrfs_put_ordered_extent(ordered);
6843 inode_tree_del(inode);
6844 btrfs_drop_extent_cache(inode, 0, (u64)-1, 0);
6846 btrfs_remove_delayed_node(inode);
6847 call_rcu(&inode->i_rcu, btrfs_i_callback);
6850 int btrfs_drop_inode(struct inode *inode)
6852 struct btrfs_root *root = BTRFS_I(inode)->root;
6854 if (btrfs_root_refs(&root->root_item) == 0 &&
6855 !btrfs_is_free_space_inode(root, inode))
6858 return generic_drop_inode(inode);
6861 static void init_once(void *foo)
6863 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
6865 inode_init_once(&ei->vfs_inode);
6868 void btrfs_destroy_cachep(void)
6870 if (btrfs_inode_cachep)
6871 kmem_cache_destroy(btrfs_inode_cachep);
6872 if (btrfs_trans_handle_cachep)
6873 kmem_cache_destroy(btrfs_trans_handle_cachep);
6874 if (btrfs_transaction_cachep)
6875 kmem_cache_destroy(btrfs_transaction_cachep);
6876 if (btrfs_path_cachep)
6877 kmem_cache_destroy(btrfs_path_cachep);
6878 if (btrfs_free_space_cachep)
6879 kmem_cache_destroy(btrfs_free_space_cachep);
6882 int btrfs_init_cachep(void)
6884 btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache",
6885 sizeof(struct btrfs_inode), 0,
6886 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, init_once);
6887 if (!btrfs_inode_cachep)
6890 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache",
6891 sizeof(struct btrfs_trans_handle), 0,
6892 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6893 if (!btrfs_trans_handle_cachep)
6896 btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache",
6897 sizeof(struct btrfs_transaction), 0,
6898 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6899 if (!btrfs_transaction_cachep)
6902 btrfs_path_cachep = kmem_cache_create("btrfs_path_cache",
6903 sizeof(struct btrfs_path), 0,
6904 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6905 if (!btrfs_path_cachep)
6908 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space_cache",
6909 sizeof(struct btrfs_free_space), 0,
6910 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
6911 if (!btrfs_free_space_cachep)
6916 btrfs_destroy_cachep();
6920 static int btrfs_getattr(struct vfsmount *mnt,
6921 struct dentry *dentry, struct kstat *stat)
6923 struct inode *inode = dentry->d_inode;
6924 u32 blocksize = inode->i_sb->s_blocksize;
6926 generic_fillattr(inode, stat);
6927 stat->dev = BTRFS_I(inode)->root->anon_dev;
6928 stat->blksize = PAGE_CACHE_SIZE;
6929 stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) +
6930 ALIGN(BTRFS_I(inode)->delalloc_bytes, blocksize)) >> 9;
6935 * If a file is moved, it will inherit the cow and compression flags of the new
6938 static void fixup_inode_flags(struct inode *dir, struct inode *inode)
6940 struct btrfs_inode *b_dir = BTRFS_I(dir);
6941 struct btrfs_inode *b_inode = BTRFS_I(inode);
6943 if (b_dir->flags & BTRFS_INODE_NODATACOW)
6944 b_inode->flags |= BTRFS_INODE_NODATACOW;
6946 b_inode->flags &= ~BTRFS_INODE_NODATACOW;
6948 if (b_dir->flags & BTRFS_INODE_COMPRESS)
6949 b_inode->flags |= BTRFS_INODE_COMPRESS;
6951 b_inode->flags &= ~BTRFS_INODE_COMPRESS;
6954 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
6955 struct inode *new_dir, struct dentry *new_dentry)
6957 struct btrfs_trans_handle *trans;
6958 struct btrfs_root *root = BTRFS_I(old_dir)->root;
6959 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
6960 struct inode *new_inode = new_dentry->d_inode;
6961 struct inode *old_inode = old_dentry->d_inode;
6962 struct timespec ctime = CURRENT_TIME;
6966 u64 old_ino = btrfs_ino(old_inode);
6968 if (btrfs_ino(new_dir) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
6971 /* we only allow rename subvolume link between subvolumes */
6972 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
6975 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
6976 (new_inode && btrfs_ino(new_inode) == BTRFS_FIRST_FREE_OBJECTID))
6979 if (S_ISDIR(old_inode->i_mode) && new_inode &&
6980 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
6983 * we're using rename to replace one file with another.
6984 * and the replacement file is large. Start IO on it now so
6985 * we don't add too much work to the end of the transaction
6987 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size &&
6988 old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
6989 filemap_flush(old_inode->i_mapping);
6991 /* close the racy window with snapshot create/destroy ioctl */
6992 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
6993 down_read(&root->fs_info->subvol_sem);
6995 * We want to reserve the absolute worst case amount of items. So if
6996 * both inodes are subvols and we need to unlink them then that would
6997 * require 4 item modifications, but if they are both normal inodes it
6998 * would require 5 item modifications, so we'll assume their normal
6999 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
7000 * should cover the worst case number of items we'll modify.
7002 trans = btrfs_start_transaction(root, 20);
7003 if (IS_ERR(trans)) {
7004 ret = PTR_ERR(trans);
7009 btrfs_record_root_in_trans(trans, dest);
7011 ret = btrfs_set_inode_index(new_dir, &index);
7015 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
7016 /* force full log commit if subvolume involved. */
7017 root->fs_info->last_trans_log_full_commit = trans->transid;
7019 ret = btrfs_insert_inode_ref(trans, dest,
7020 new_dentry->d_name.name,
7021 new_dentry->d_name.len,
7023 btrfs_ino(new_dir), index);
7027 * this is an ugly little race, but the rename is required
7028 * to make sure that if we crash, the inode is either at the
7029 * old name or the new one. pinning the log transaction lets
7030 * us make sure we don't allow a log commit to come in after
7031 * we unlink the name but before we add the new name back in.
7033 btrfs_pin_log_trans(root);
7036 * make sure the inode gets flushed if it is replacing
7039 if (new_inode && new_inode->i_size && S_ISREG(old_inode->i_mode))
7040 btrfs_add_ordered_operation(trans, root, old_inode);
7042 old_dir->i_ctime = old_dir->i_mtime = ctime;
7043 new_dir->i_ctime = new_dir->i_mtime = ctime;
7044 old_inode->i_ctime = ctime;
7046 if (old_dentry->d_parent != new_dentry->d_parent)
7047 btrfs_record_unlink_dir(trans, old_dir, old_inode, 1);
7049 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
7050 root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
7051 ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid,
7052 old_dentry->d_name.name,
7053 old_dentry->d_name.len);
7055 ret = __btrfs_unlink_inode(trans, root, old_dir,
7056 old_dentry->d_inode,
7057 old_dentry->d_name.name,
7058 old_dentry->d_name.len);
7060 ret = btrfs_update_inode(trans, root, old_inode);
7065 new_inode->i_ctime = CURRENT_TIME;
7066 if (unlikely(btrfs_ino(new_inode) ==
7067 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
7068 root_objectid = BTRFS_I(new_inode)->location.objectid;
7069 ret = btrfs_unlink_subvol(trans, dest, new_dir,
7071 new_dentry->d_name.name,
7072 new_dentry->d_name.len);
7073 BUG_ON(new_inode->i_nlink == 0);
7075 ret = btrfs_unlink_inode(trans, dest, new_dir,
7076 new_dentry->d_inode,
7077 new_dentry->d_name.name,
7078 new_dentry->d_name.len);
7081 if (new_inode->i_nlink == 0) {
7082 ret = btrfs_orphan_add(trans, new_dentry->d_inode);
7087 fixup_inode_flags(new_dir, old_inode);
7089 ret = btrfs_add_link(trans, new_dir, old_inode,
7090 new_dentry->d_name.name,
7091 new_dentry->d_name.len, 0, index);
7094 if (old_ino != BTRFS_FIRST_FREE_OBJECTID) {
7095 struct dentry *parent = new_dentry->d_parent;
7096 btrfs_log_new_name(trans, old_inode, old_dir, parent);
7097 btrfs_end_log_trans(root);
7100 btrfs_end_transaction_throttle(trans, root);
7102 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
7103 up_read(&root->fs_info->subvol_sem);
7109 * some fairly slow code that needs optimization. This walks the list
7110 * of all the inodes with pending delalloc and forces them to disk.
7112 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput)
7114 struct list_head *head = &root->fs_info->delalloc_inodes;
7115 struct btrfs_inode *binode;
7116 struct inode *inode;
7118 if (root->fs_info->sb->s_flags & MS_RDONLY)
7121 spin_lock(&root->fs_info->delalloc_lock);
7122 while (!list_empty(head)) {
7123 binode = list_entry(head->next, struct btrfs_inode,
7125 inode = igrab(&binode->vfs_inode);
7127 list_del_init(&binode->delalloc_inodes);
7128 spin_unlock(&root->fs_info->delalloc_lock);
7130 filemap_flush(inode->i_mapping);
7132 btrfs_add_delayed_iput(inode);
7137 spin_lock(&root->fs_info->delalloc_lock);
7139 spin_unlock(&root->fs_info->delalloc_lock);
7141 /* the filemap_flush will queue IO into the worker threads, but
7142 * we have to make sure the IO is actually started and that
7143 * ordered extents get created before we return
7145 atomic_inc(&root->fs_info->async_submit_draining);
7146 while (atomic_read(&root->fs_info->nr_async_submits) ||
7147 atomic_read(&root->fs_info->async_delalloc_pages)) {
7148 wait_event(root->fs_info->async_submit_wait,
7149 (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
7150 atomic_read(&root->fs_info->async_delalloc_pages) == 0));
7152 atomic_dec(&root->fs_info->async_submit_draining);
7156 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
7157 const char *symname)
7159 struct btrfs_trans_handle *trans;
7160 struct btrfs_root *root = BTRFS_I(dir)->root;
7161 struct btrfs_path *path;
7162 struct btrfs_key key;
7163 struct inode *inode = NULL;
7171 struct btrfs_file_extent_item *ei;
7172 struct extent_buffer *leaf;
7173 unsigned long nr = 0;
7175 name_len = strlen(symname) + 1;
7176 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
7177 return -ENAMETOOLONG;
7180 * 2 items for inode item and ref
7181 * 2 items for dir items
7182 * 1 item for xattr if selinux is on
7184 trans = btrfs_start_transaction(root, 5);
7186 return PTR_ERR(trans);
7188 err = btrfs_find_free_ino(root, &objectid);
7192 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
7193 dentry->d_name.len, btrfs_ino(dir), objectid,
7194 S_IFLNK|S_IRWXUGO, &index);
7195 if (IS_ERR(inode)) {
7196 err = PTR_ERR(inode);
7200 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
7207 * If the active LSM wants to access the inode during
7208 * d_instantiate it needs these. Smack checks to see
7209 * if the filesystem supports xattrs by looking at the
7212 inode->i_fop = &btrfs_file_operations;
7213 inode->i_op = &btrfs_file_inode_operations;
7215 err = btrfs_add_nondir(trans, dir, dentry, inode, 0, index);
7219 inode->i_mapping->a_ops = &btrfs_aops;
7220 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
7221 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
7226 path = btrfs_alloc_path();
7232 key.objectid = btrfs_ino(inode);
7234 btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
7235 datasize = btrfs_file_extent_calc_inline_size(name_len);
7236 err = btrfs_insert_empty_item(trans, root, path, &key,
7240 btrfs_free_path(path);
7243 leaf = path->nodes[0];
7244 ei = btrfs_item_ptr(leaf, path->slots[0],
7245 struct btrfs_file_extent_item);
7246 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
7247 btrfs_set_file_extent_type(leaf, ei,
7248 BTRFS_FILE_EXTENT_INLINE);
7249 btrfs_set_file_extent_encryption(leaf, ei, 0);
7250 btrfs_set_file_extent_compression(leaf, ei, 0);
7251 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
7252 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
7254 ptr = btrfs_file_extent_inline_start(ei);
7255 write_extent_buffer(leaf, symname, ptr, name_len);
7256 btrfs_mark_buffer_dirty(leaf);
7257 btrfs_free_path(path);
7259 inode->i_op = &btrfs_symlink_inode_operations;
7260 inode->i_mapping->a_ops = &btrfs_symlink_aops;
7261 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
7262 inode_set_bytes(inode, name_len);
7263 btrfs_i_size_write(inode, name_len - 1);
7264 err = btrfs_update_inode(trans, root, inode);
7270 d_instantiate(dentry, inode);
7271 nr = trans->blocks_used;
7272 btrfs_end_transaction_throttle(trans, root);
7274 inode_dec_link_count(inode);
7277 btrfs_btree_balance_dirty(root, nr);
7281 static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
7282 u64 start, u64 num_bytes, u64 min_size,
7283 loff_t actual_len, u64 *alloc_hint,
7284 struct btrfs_trans_handle *trans)
7286 struct btrfs_root *root = BTRFS_I(inode)->root;
7287 struct btrfs_key ins;
7288 u64 cur_offset = start;
7291 bool own_trans = true;
7295 while (num_bytes > 0) {
7297 trans = btrfs_start_transaction(root, 3);
7298 if (IS_ERR(trans)) {
7299 ret = PTR_ERR(trans);
7304 ret = btrfs_reserve_extent(trans, root, num_bytes, min_size,
7305 0, *alloc_hint, (u64)-1, &ins, 1);
7308 btrfs_end_transaction(trans, root);
7312 ret = insert_reserved_file_extent(trans, inode,
7313 cur_offset, ins.objectid,
7314 ins.offset, ins.offset,
7315 ins.offset, 0, 0, 0,
7316 BTRFS_FILE_EXTENT_PREALLOC);
7318 btrfs_drop_extent_cache(inode, cur_offset,
7319 cur_offset + ins.offset -1, 0);
7321 num_bytes -= ins.offset;
7322 cur_offset += ins.offset;
7323 *alloc_hint = ins.objectid + ins.offset;
7325 inode->i_ctime = CURRENT_TIME;
7326 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
7327 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
7328 (actual_len > inode->i_size) &&
7329 (cur_offset > inode->i_size)) {
7330 if (cur_offset > actual_len)
7331 i_size = actual_len;
7333 i_size = cur_offset;
7334 i_size_write(inode, i_size);
7335 btrfs_ordered_update_i_size(inode, i_size, NULL);
7338 ret = btrfs_update_inode(trans, root, inode);
7342 btrfs_end_transaction(trans, root);
7347 int btrfs_prealloc_file_range(struct inode *inode, int mode,
7348 u64 start, u64 num_bytes, u64 min_size,
7349 loff_t actual_len, u64 *alloc_hint)
7351 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
7352 min_size, actual_len, alloc_hint,
7356 int btrfs_prealloc_file_range_trans(struct inode *inode,
7357 struct btrfs_trans_handle *trans, int mode,
7358 u64 start, u64 num_bytes, u64 min_size,
7359 loff_t actual_len, u64 *alloc_hint)
7361 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
7362 min_size, actual_len, alloc_hint, trans);
7365 static int btrfs_set_page_dirty(struct page *page)
7367 return __set_page_dirty_nobuffers(page);
7370 static int btrfs_permission(struct inode *inode, int mask)
7372 struct btrfs_root *root = BTRFS_I(inode)->root;
7373 umode_t mode = inode->i_mode;
7375 if (mask & MAY_WRITE &&
7376 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) {
7377 if (btrfs_root_readonly(root))
7379 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
7382 return generic_permission(inode, mask);
7385 static const struct inode_operations btrfs_dir_inode_operations = {
7386 .getattr = btrfs_getattr,
7387 .lookup = btrfs_lookup,
7388 .create = btrfs_create,
7389 .unlink = btrfs_unlink,
7391 .mkdir = btrfs_mkdir,
7392 .rmdir = btrfs_rmdir,
7393 .rename = btrfs_rename,
7394 .symlink = btrfs_symlink,
7395 .setattr = btrfs_setattr,
7396 .mknod = btrfs_mknod,
7397 .setxattr = btrfs_setxattr,
7398 .getxattr = btrfs_getxattr,
7399 .listxattr = btrfs_listxattr,
7400 .removexattr = btrfs_removexattr,
7401 .permission = btrfs_permission,
7402 .get_acl = btrfs_get_acl,
7404 static const struct inode_operations btrfs_dir_ro_inode_operations = {
7405 .lookup = btrfs_lookup,
7406 .permission = btrfs_permission,
7407 .get_acl = btrfs_get_acl,
7410 static const struct file_operations btrfs_dir_file_operations = {
7411 .llseek = generic_file_llseek,
7412 .read = generic_read_dir,
7413 .readdir = btrfs_real_readdir,
7414 .unlocked_ioctl = btrfs_ioctl,
7415 #ifdef CONFIG_COMPAT
7416 .compat_ioctl = btrfs_ioctl,
7418 .release = btrfs_release_file,
7419 .fsync = btrfs_sync_file,
7422 static struct extent_io_ops btrfs_extent_io_ops = {
7423 .fill_delalloc = run_delalloc_range,
7424 .submit_bio_hook = btrfs_submit_bio_hook,
7425 .merge_bio_hook = btrfs_merge_bio_hook,
7426 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
7427 .writepage_end_io_hook = btrfs_writepage_end_io_hook,
7428 .writepage_start_hook = btrfs_writepage_start_hook,
7429 .set_bit_hook = btrfs_set_bit_hook,
7430 .clear_bit_hook = btrfs_clear_bit_hook,
7431 .merge_extent_hook = btrfs_merge_extent_hook,
7432 .split_extent_hook = btrfs_split_extent_hook,
7436 * btrfs doesn't support the bmap operation because swapfiles
7437 * use bmap to make a mapping of extents in the file. They assume
7438 * these extents won't change over the life of the file and they
7439 * use the bmap result to do IO directly to the drive.
7441 * the btrfs bmap call would return logical addresses that aren't
7442 * suitable for IO and they also will change frequently as COW
7443 * operations happen. So, swapfile + btrfs == corruption.
7445 * For now we're avoiding this by dropping bmap.
7447 static const struct address_space_operations btrfs_aops = {
7448 .readpage = btrfs_readpage,
7449 .writepage = btrfs_writepage,
7450 .writepages = btrfs_writepages,
7451 .readpages = btrfs_readpages,
7452 .direct_IO = btrfs_direct_IO,
7453 .invalidatepage = btrfs_invalidatepage,
7454 .releasepage = btrfs_releasepage,
7455 .set_page_dirty = btrfs_set_page_dirty,
7456 .error_remove_page = generic_error_remove_page,
7459 static const struct address_space_operations btrfs_symlink_aops = {
7460 .readpage = btrfs_readpage,
7461 .writepage = btrfs_writepage,
7462 .invalidatepage = btrfs_invalidatepage,
7463 .releasepage = btrfs_releasepage,
7466 static const struct inode_operations btrfs_file_inode_operations = {
7467 .getattr = btrfs_getattr,
7468 .setattr = btrfs_setattr,
7469 .setxattr = btrfs_setxattr,
7470 .getxattr = btrfs_getxattr,
7471 .listxattr = btrfs_listxattr,
7472 .removexattr = btrfs_removexattr,
7473 .permission = btrfs_permission,
7474 .fiemap = btrfs_fiemap,
7475 .get_acl = btrfs_get_acl,
7477 static const struct inode_operations btrfs_special_inode_operations = {
7478 .getattr = btrfs_getattr,
7479 .setattr = btrfs_setattr,
7480 .permission = btrfs_permission,
7481 .setxattr = btrfs_setxattr,
7482 .getxattr = btrfs_getxattr,
7483 .listxattr = btrfs_listxattr,
7484 .removexattr = btrfs_removexattr,
7485 .get_acl = btrfs_get_acl,
7487 static const struct inode_operations btrfs_symlink_inode_operations = {
7488 .readlink = generic_readlink,
7489 .follow_link = page_follow_link_light,
7490 .put_link = page_put_link,
7491 .getattr = btrfs_getattr,
7492 .setattr = btrfs_setattr,
7493 .permission = btrfs_permission,
7494 .setxattr = btrfs_setxattr,
7495 .getxattr = btrfs_getxattr,
7496 .listxattr = btrfs_listxattr,
7497 .removexattr = btrfs_removexattr,
7498 .get_acl = btrfs_get_acl,
7501 const struct dentry_operations btrfs_dentry_operations = {
7502 .d_delete = btrfs_dentry_delete,
7503 .d_release = btrfs_dentry_release,