1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2007 Oracle. All rights reserved.
6 #include <linux/kernel.h>
8 #include <linux/buffer_head.h>
9 #include <linux/file.h>
11 #include <linux/pagemap.h>
12 #include <linux/highmem.h>
13 #include <linux/time.h>
14 #include <linux/init.h>
15 #include <linux/string.h>
16 #include <linux/backing-dev.h>
17 #include <linux/writeback.h>
18 #include <linux/compat.h>
19 #include <linux/xattr.h>
20 #include <linux/posix_acl.h>
21 #include <linux/falloc.h>
22 #include <linux/slab.h>
23 #include <linux/ratelimit.h>
24 #include <linux/btrfs.h>
25 #include <linux/blkdev.h>
26 #include <linux/posix_acl_xattr.h>
27 #include <linux/uio.h>
28 #include <linux/magic.h>
29 #include <linux/iversion.h>
30 #include <linux/swap.h>
31 #include <linux/migrate.h>
32 #include <linux/sched/mm.h>
33 #include <asm/unaligned.h>
37 #include "transaction.h"
38 #include "btrfs_inode.h"
39 #include "print-tree.h"
40 #include "ordered-data.h"
44 #include "compression.h"
46 #include "free-space-cache.h"
47 #include "inode-map.h"
50 #include "delalloc-space.h"
51 #include "block-group.h"
52 #include "space-info.h"
54 struct btrfs_iget_args {
56 struct btrfs_root *root;
59 struct btrfs_dio_data {
61 u64 unsubmitted_oe_range_start;
62 u64 unsubmitted_oe_range_end;
66 static const struct inode_operations btrfs_dir_inode_operations;
67 static const struct inode_operations btrfs_symlink_inode_operations;
68 static const struct inode_operations btrfs_special_inode_operations;
69 static const struct inode_operations btrfs_file_inode_operations;
70 static const struct address_space_operations btrfs_aops;
71 static const struct file_operations btrfs_dir_file_operations;
72 static const struct extent_io_ops btrfs_extent_io_ops;
74 static struct kmem_cache *btrfs_inode_cachep;
75 struct kmem_cache *btrfs_trans_handle_cachep;
76 struct kmem_cache *btrfs_path_cachep;
77 struct kmem_cache *btrfs_free_space_cachep;
78 struct kmem_cache *btrfs_free_space_bitmap_cachep;
80 static int btrfs_setsize(struct inode *inode, struct iattr *attr);
81 static int btrfs_truncate(struct inode *inode, bool skip_writeback);
82 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent);
83 static noinline int cow_file_range(struct inode *inode,
84 struct page *locked_page,
85 u64 start, u64 end, int *page_started,
86 unsigned long *nr_written, int unlock);
87 static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len,
88 u64 orig_start, u64 block_start,
89 u64 block_len, u64 orig_block_len,
90 u64 ram_bytes, int compress_type,
93 static void __endio_write_update_ordered(struct inode *inode,
94 const u64 offset, const u64 bytes,
98 * Cleanup all submitted ordered extents in specified range to handle errors
99 * from the btrfs_run_delalloc_range() callback.
101 * NOTE: caller must ensure that when an error happens, it can not call
102 * extent_clear_unlock_delalloc() to clear both the bits EXTENT_DO_ACCOUNTING
103 * and EXTENT_DELALLOC simultaneously, because that causes the reserved metadata
104 * to be released, which we want to happen only when finishing the ordered
105 * extent (btrfs_finish_ordered_io()).
107 static inline void btrfs_cleanup_ordered_extents(struct inode *inode,
108 struct page *locked_page,
109 u64 offset, u64 bytes)
111 unsigned long index = offset >> PAGE_SHIFT;
112 unsigned long end_index = (offset + bytes - 1) >> PAGE_SHIFT;
113 u64 page_start = page_offset(locked_page);
114 u64 page_end = page_start + PAGE_SIZE - 1;
118 while (index <= end_index) {
119 page = find_get_page(inode->i_mapping, index);
123 ClearPagePrivate2(page);
128 * In case this page belongs to the delalloc range being instantiated
129 * then skip it, since the first page of a range is going to be
130 * properly cleaned up by the caller of run_delalloc_range
132 if (page_start >= offset && page_end <= (offset + bytes - 1)) {
137 return __endio_write_update_ordered(inode, offset, bytes, false);
140 static int btrfs_dirty_inode(struct inode *inode);
142 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
143 void btrfs_test_inode_set_ops(struct inode *inode)
145 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
149 static int btrfs_init_inode_security(struct btrfs_trans_handle *trans,
150 struct inode *inode, struct inode *dir,
151 const struct qstr *qstr)
155 err = btrfs_init_acl(trans, inode, dir);
157 err = btrfs_xattr_security_init(trans, inode, dir, qstr);
162 * this does all the hard work for inserting an inline extent into
163 * the btree. The caller should have done a btrfs_drop_extents so that
164 * no overlapping inline items exist in the btree
166 static int insert_inline_extent(struct btrfs_trans_handle *trans,
167 struct btrfs_path *path, int extent_inserted,
168 struct btrfs_root *root, struct inode *inode,
169 u64 start, size_t size, size_t compressed_size,
171 struct page **compressed_pages)
173 struct extent_buffer *leaf;
174 struct page *page = NULL;
177 struct btrfs_file_extent_item *ei;
179 size_t cur_size = size;
180 unsigned long offset;
182 ASSERT((compressed_size > 0 && compressed_pages) ||
183 (compressed_size == 0 && !compressed_pages));
185 if (compressed_size && compressed_pages)
186 cur_size = compressed_size;
188 inode_add_bytes(inode, size);
190 if (!extent_inserted) {
191 struct btrfs_key key;
194 key.objectid = btrfs_ino(BTRFS_I(inode));
196 key.type = BTRFS_EXTENT_DATA_KEY;
198 datasize = btrfs_file_extent_calc_inline_size(cur_size);
199 path->leave_spinning = 1;
200 ret = btrfs_insert_empty_item(trans, root, path, &key,
205 leaf = path->nodes[0];
206 ei = btrfs_item_ptr(leaf, path->slots[0],
207 struct btrfs_file_extent_item);
208 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
209 btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE);
210 btrfs_set_file_extent_encryption(leaf, ei, 0);
211 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
212 btrfs_set_file_extent_ram_bytes(leaf, ei, size);
213 ptr = btrfs_file_extent_inline_start(ei);
215 if (compress_type != BTRFS_COMPRESS_NONE) {
218 while (compressed_size > 0) {
219 cpage = compressed_pages[i];
220 cur_size = min_t(unsigned long, compressed_size,
223 kaddr = kmap_atomic(cpage);
224 write_extent_buffer(leaf, kaddr, ptr, cur_size);
225 kunmap_atomic(kaddr);
229 compressed_size -= cur_size;
231 btrfs_set_file_extent_compression(leaf, ei,
234 page = find_get_page(inode->i_mapping,
235 start >> PAGE_SHIFT);
236 btrfs_set_file_extent_compression(leaf, ei, 0);
237 kaddr = kmap_atomic(page);
238 offset = offset_in_page(start);
239 write_extent_buffer(leaf, kaddr + offset, ptr, size);
240 kunmap_atomic(kaddr);
243 btrfs_mark_buffer_dirty(leaf);
244 btrfs_release_path(path);
247 * We align size to sectorsize for inline extents just for simplicity
250 size = ALIGN(size, root->fs_info->sectorsize);
251 ret = btrfs_inode_set_file_extent_range(BTRFS_I(inode), start, size);
256 * we're an inline extent, so nobody can
257 * extend the file past i_size without locking
258 * a page we already have locked.
260 * We must do any isize and inode updates
261 * before we unlock the pages. Otherwise we
262 * could end up racing with unlink.
264 BTRFS_I(inode)->disk_i_size = inode->i_size;
265 ret = btrfs_update_inode(trans, root, inode);
273 * conditionally insert an inline extent into the file. This
274 * does the checks required to make sure the data is small enough
275 * to fit as an inline extent.
277 static noinline int cow_file_range_inline(struct inode *inode, u64 start,
278 u64 end, size_t compressed_size,
280 struct page **compressed_pages)
282 struct btrfs_root *root = BTRFS_I(inode)->root;
283 struct btrfs_fs_info *fs_info = root->fs_info;
284 struct btrfs_trans_handle *trans;
285 u64 isize = i_size_read(inode);
286 u64 actual_end = min(end + 1, isize);
287 u64 inline_len = actual_end - start;
288 u64 aligned_end = ALIGN(end, fs_info->sectorsize);
289 u64 data_len = inline_len;
291 struct btrfs_path *path;
292 int extent_inserted = 0;
293 u32 extent_item_size;
296 data_len = compressed_size;
299 actual_end > fs_info->sectorsize ||
300 data_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info) ||
302 (actual_end & (fs_info->sectorsize - 1)) == 0) ||
304 data_len > fs_info->max_inline) {
308 path = btrfs_alloc_path();
312 trans = btrfs_join_transaction(root);
314 btrfs_free_path(path);
315 return PTR_ERR(trans);
317 trans->block_rsv = &BTRFS_I(inode)->block_rsv;
319 if (compressed_size && compressed_pages)
320 extent_item_size = btrfs_file_extent_calc_inline_size(
323 extent_item_size = btrfs_file_extent_calc_inline_size(
326 ret = __btrfs_drop_extents(trans, root, inode, path,
327 start, aligned_end, NULL,
328 1, 1, extent_item_size, &extent_inserted);
330 btrfs_abort_transaction(trans, ret);
334 if (isize > actual_end)
335 inline_len = min_t(u64, isize, actual_end);
336 ret = insert_inline_extent(trans, path, extent_inserted,
338 inline_len, compressed_size,
339 compress_type, compressed_pages);
340 if (ret && ret != -ENOSPC) {
341 btrfs_abort_transaction(trans, ret);
343 } else if (ret == -ENOSPC) {
348 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
349 btrfs_drop_extent_cache(BTRFS_I(inode), start, aligned_end - 1, 0);
352 * Don't forget to free the reserved space, as for inlined extent
353 * it won't count as data extent, free them directly here.
354 * And at reserve time, it's always aligned to page size, so
355 * just free one page here.
357 btrfs_qgroup_free_data(inode, NULL, 0, PAGE_SIZE);
358 btrfs_free_path(path);
359 btrfs_end_transaction(trans);
363 struct async_extent {
368 unsigned long nr_pages;
370 struct list_head list;
375 struct page *locked_page;
378 unsigned int write_flags;
379 struct list_head extents;
380 struct cgroup_subsys_state *blkcg_css;
381 struct btrfs_work work;
386 /* Number of chunks in flight; must be first in the structure */
388 struct async_chunk chunks[];
391 static noinline int add_async_extent(struct async_chunk *cow,
392 u64 start, u64 ram_size,
395 unsigned long nr_pages,
398 struct async_extent *async_extent;
400 async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
401 BUG_ON(!async_extent); /* -ENOMEM */
402 async_extent->start = start;
403 async_extent->ram_size = ram_size;
404 async_extent->compressed_size = compressed_size;
405 async_extent->pages = pages;
406 async_extent->nr_pages = nr_pages;
407 async_extent->compress_type = compress_type;
408 list_add_tail(&async_extent->list, &cow->extents);
413 * Check if the inode has flags compatible with compression
415 static inline bool inode_can_compress(struct inode *inode)
417 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW ||
418 BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
424 * Check if the inode needs to be submitted to compression, based on mount
425 * options, defragmentation, properties or heuristics.
427 static inline int inode_need_compress(struct inode *inode, u64 start, u64 end)
429 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
431 if (!inode_can_compress(inode)) {
432 WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG),
433 KERN_ERR "BTRFS: unexpected compression for ino %llu\n",
434 btrfs_ino(BTRFS_I(inode)));
438 if (btrfs_test_opt(fs_info, FORCE_COMPRESS))
441 if (BTRFS_I(inode)->defrag_compress)
443 /* bad compression ratios */
444 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS)
446 if (btrfs_test_opt(fs_info, COMPRESS) ||
447 BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS ||
448 BTRFS_I(inode)->prop_compress)
449 return btrfs_compress_heuristic(inode, start, end);
453 static inline void inode_should_defrag(struct btrfs_inode *inode,
454 u64 start, u64 end, u64 num_bytes, u64 small_write)
456 /* If this is a small write inside eof, kick off a defrag */
457 if (num_bytes < small_write &&
458 (start > 0 || end + 1 < inode->disk_i_size))
459 btrfs_add_inode_defrag(NULL, inode);
463 * we create compressed extents in two phases. The first
464 * phase compresses a range of pages that have already been
465 * locked (both pages and state bits are locked).
467 * This is done inside an ordered work queue, and the compression
468 * is spread across many cpus. The actual IO submission is step
469 * two, and the ordered work queue takes care of making sure that
470 * happens in the same order things were put onto the queue by
471 * writepages and friends.
473 * If this code finds it can't get good compression, it puts an
474 * entry onto the work queue to write the uncompressed bytes. This
475 * makes sure that both compressed inodes and uncompressed inodes
476 * are written in the same order that the flusher thread sent them
479 static noinline int compress_file_range(struct async_chunk *async_chunk)
481 struct inode *inode = async_chunk->inode;
482 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
483 u64 blocksize = fs_info->sectorsize;
484 u64 start = async_chunk->start;
485 u64 end = async_chunk->end;
489 struct page **pages = NULL;
490 unsigned long nr_pages;
491 unsigned long total_compressed = 0;
492 unsigned long total_in = 0;
495 int compress_type = fs_info->compress_type;
496 int compressed_extents = 0;
499 inode_should_defrag(BTRFS_I(inode), start, end, end - start + 1,
503 * We need to save i_size before now because it could change in between
504 * us evaluating the size and assigning it. This is because we lock and
505 * unlock the page in truncate and fallocate, and then modify the i_size
508 * The barriers are to emulate READ_ONCE, remove that once i_size_read
512 i_size = i_size_read(inode);
514 actual_end = min_t(u64, i_size, end + 1);
517 nr_pages = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1;
518 BUILD_BUG_ON((BTRFS_MAX_COMPRESSED % PAGE_SIZE) != 0);
519 nr_pages = min_t(unsigned long, nr_pages,
520 BTRFS_MAX_COMPRESSED / PAGE_SIZE);
523 * we don't want to send crud past the end of i_size through
524 * compression, that's just a waste of CPU time. So, if the
525 * end of the file is before the start of our current
526 * requested range of bytes, we bail out to the uncompressed
527 * cleanup code that can deal with all of this.
529 * It isn't really the fastest way to fix things, but this is a
530 * very uncommon corner.
532 if (actual_end <= start)
533 goto cleanup_and_bail_uncompressed;
535 total_compressed = actual_end - start;
538 * skip compression for a small file range(<=blocksize) that
539 * isn't an inline extent, since it doesn't save disk space at all.
541 if (total_compressed <= blocksize &&
542 (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size))
543 goto cleanup_and_bail_uncompressed;
545 total_compressed = min_t(unsigned long, total_compressed,
546 BTRFS_MAX_UNCOMPRESSED);
551 * we do compression for mount -o compress and when the
552 * inode has not been flagged as nocompress. This flag can
553 * change at any time if we discover bad compression ratios.
555 if (inode_need_compress(inode, start, end)) {
557 pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS);
559 /* just bail out to the uncompressed code */
564 if (BTRFS_I(inode)->defrag_compress)
565 compress_type = BTRFS_I(inode)->defrag_compress;
566 else if (BTRFS_I(inode)->prop_compress)
567 compress_type = BTRFS_I(inode)->prop_compress;
570 * we need to call clear_page_dirty_for_io on each
571 * page in the range. Otherwise applications with the file
572 * mmap'd can wander in and change the page contents while
573 * we are compressing them.
575 * If the compression fails for any reason, we set the pages
576 * dirty again later on.
578 * Note that the remaining part is redirtied, the start pointer
579 * has moved, the end is the original one.
582 extent_range_clear_dirty_for_io(inode, start, end);
586 /* Compression level is applied here and only here */
587 ret = btrfs_compress_pages(
588 compress_type | (fs_info->compress_level << 4),
589 inode->i_mapping, start,
596 unsigned long offset = offset_in_page(total_compressed);
597 struct page *page = pages[nr_pages - 1];
600 /* zero the tail end of the last page, we might be
601 * sending it down to disk
604 kaddr = kmap_atomic(page);
605 memset(kaddr + offset, 0,
607 kunmap_atomic(kaddr);
614 /* lets try to make an inline extent */
615 if (ret || total_in < actual_end) {
616 /* we didn't compress the entire range, try
617 * to make an uncompressed inline extent.
619 ret = cow_file_range_inline(inode, start, end, 0,
620 BTRFS_COMPRESS_NONE, NULL);
622 /* try making a compressed inline extent */
623 ret = cow_file_range_inline(inode, start, end,
625 compress_type, pages);
628 unsigned long clear_flags = EXTENT_DELALLOC |
629 EXTENT_DELALLOC_NEW | EXTENT_DEFRAG |
630 EXTENT_DO_ACCOUNTING;
631 unsigned long page_error_op;
633 page_error_op = ret < 0 ? PAGE_SET_ERROR : 0;
636 * inline extent creation worked or returned error,
637 * we don't need to create any more async work items.
638 * Unlock and free up our temp pages.
640 * We use DO_ACCOUNTING here because we need the
641 * delalloc_release_metadata to be done _after_ we drop
642 * our outstanding extent for clearing delalloc for this
645 extent_clear_unlock_delalloc(inode, start, end, NULL,
653 for (i = 0; i < nr_pages; i++) {
654 WARN_ON(pages[i]->mapping);
665 * we aren't doing an inline extent round the compressed size
666 * up to a block size boundary so the allocator does sane
669 total_compressed = ALIGN(total_compressed, blocksize);
672 * one last check to make sure the compression is really a
673 * win, compare the page count read with the blocks on disk,
674 * compression must free at least one sector size
676 total_in = ALIGN(total_in, PAGE_SIZE);
677 if (total_compressed + blocksize <= total_in) {
678 compressed_extents++;
681 * The async work queues will take care of doing actual
682 * allocation on disk for these compressed pages, and
683 * will submit them to the elevator.
685 add_async_extent(async_chunk, start, total_in,
686 total_compressed, pages, nr_pages,
689 if (start + total_in < end) {
695 return compressed_extents;
700 * the compression code ran but failed to make things smaller,
701 * free any pages it allocated and our page pointer array
703 for (i = 0; i < nr_pages; i++) {
704 WARN_ON(pages[i]->mapping);
709 total_compressed = 0;
712 /* flag the file so we don't compress in the future */
713 if (!btrfs_test_opt(fs_info, FORCE_COMPRESS) &&
714 !(BTRFS_I(inode)->prop_compress)) {
715 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
718 cleanup_and_bail_uncompressed:
720 * No compression, but we still need to write the pages in the file
721 * we've been given so far. redirty the locked page if it corresponds
722 * to our extent and set things up for the async work queue to run
723 * cow_file_range to do the normal delalloc dance.
725 if (async_chunk->locked_page &&
726 (page_offset(async_chunk->locked_page) >= start &&
727 page_offset(async_chunk->locked_page)) <= end) {
728 __set_page_dirty_nobuffers(async_chunk->locked_page);
729 /* unlocked later on in the async handlers */
733 extent_range_redirty_for_io(inode, start, end);
734 add_async_extent(async_chunk, start, end - start + 1, 0, NULL, 0,
735 BTRFS_COMPRESS_NONE);
736 compressed_extents++;
738 return compressed_extents;
741 static void free_async_extent_pages(struct async_extent *async_extent)
745 if (!async_extent->pages)
748 for (i = 0; i < async_extent->nr_pages; i++) {
749 WARN_ON(async_extent->pages[i]->mapping);
750 put_page(async_extent->pages[i]);
752 kfree(async_extent->pages);
753 async_extent->nr_pages = 0;
754 async_extent->pages = NULL;
758 * phase two of compressed writeback. This is the ordered portion
759 * of the code, which only gets called in the order the work was
760 * queued. We walk all the async extents created by compress_file_range
761 * and send them down to the disk.
763 static noinline void submit_compressed_extents(struct async_chunk *async_chunk)
765 struct inode *inode = async_chunk->inode;
766 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
767 struct async_extent *async_extent;
769 struct btrfs_key ins;
770 struct extent_map *em;
771 struct btrfs_root *root = BTRFS_I(inode)->root;
772 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
776 while (!list_empty(&async_chunk->extents)) {
777 async_extent = list_entry(async_chunk->extents.next,
778 struct async_extent, list);
779 list_del(&async_extent->list);
782 lock_extent(io_tree, async_extent->start,
783 async_extent->start + async_extent->ram_size - 1);
784 /* did the compression code fall back to uncompressed IO? */
785 if (!async_extent->pages) {
786 int page_started = 0;
787 unsigned long nr_written = 0;
789 /* allocate blocks */
790 ret = cow_file_range(inode, async_chunk->locked_page,
792 async_extent->start +
793 async_extent->ram_size - 1,
794 &page_started, &nr_written, 0);
799 * if page_started, cow_file_range inserted an
800 * inline extent and took care of all the unlocking
801 * and IO for us. Otherwise, we need to submit
802 * all those pages down to the drive.
804 if (!page_started && !ret)
805 extent_write_locked_range(inode,
807 async_extent->start +
808 async_extent->ram_size - 1,
810 else if (ret && async_chunk->locked_page)
811 unlock_page(async_chunk->locked_page);
817 ret = btrfs_reserve_extent(root, async_extent->ram_size,
818 async_extent->compressed_size,
819 async_extent->compressed_size,
820 0, alloc_hint, &ins, 1, 1);
822 free_async_extent_pages(async_extent);
824 if (ret == -ENOSPC) {
825 unlock_extent(io_tree, async_extent->start,
826 async_extent->start +
827 async_extent->ram_size - 1);
830 * we need to redirty the pages if we decide to
831 * fallback to uncompressed IO, otherwise we
832 * will not submit these pages down to lower
835 extent_range_redirty_for_io(inode,
837 async_extent->start +
838 async_extent->ram_size - 1);
845 * here we're doing allocation and writeback of the
848 em = create_io_em(inode, async_extent->start,
849 async_extent->ram_size, /* len */
850 async_extent->start, /* orig_start */
851 ins.objectid, /* block_start */
852 ins.offset, /* block_len */
853 ins.offset, /* orig_block_len */
854 async_extent->ram_size, /* ram_bytes */
855 async_extent->compress_type,
856 BTRFS_ORDERED_COMPRESSED);
858 /* ret value is not necessary due to void function */
859 goto out_free_reserve;
862 ret = btrfs_add_ordered_extent_compress(inode,
865 async_extent->ram_size,
867 BTRFS_ORDERED_COMPRESSED,
868 async_extent->compress_type);
870 btrfs_drop_extent_cache(BTRFS_I(inode),
872 async_extent->start +
873 async_extent->ram_size - 1, 0);
874 goto out_free_reserve;
876 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
879 * clear dirty, set writeback and unlock the pages.
881 extent_clear_unlock_delalloc(inode, async_extent->start,
882 async_extent->start +
883 async_extent->ram_size - 1,
884 NULL, EXTENT_LOCKED | EXTENT_DELALLOC,
885 PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
887 if (btrfs_submit_compressed_write(inode,
889 async_extent->ram_size,
891 ins.offset, async_extent->pages,
892 async_extent->nr_pages,
893 async_chunk->write_flags,
894 async_chunk->blkcg_css)) {
895 struct page *p = async_extent->pages[0];
896 const u64 start = async_extent->start;
897 const u64 end = start + async_extent->ram_size - 1;
899 p->mapping = inode->i_mapping;
900 btrfs_writepage_endio_finish_ordered(p, start, end, 0);
903 extent_clear_unlock_delalloc(inode, start, end,
907 free_async_extent_pages(async_extent);
909 alloc_hint = ins.objectid + ins.offset;
915 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
916 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1);
918 extent_clear_unlock_delalloc(inode, async_extent->start,
919 async_extent->start +
920 async_extent->ram_size - 1,
921 NULL, EXTENT_LOCKED | EXTENT_DELALLOC |
922 EXTENT_DELALLOC_NEW |
923 EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING,
924 PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
925 PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK |
927 free_async_extent_pages(async_extent);
932 static u64 get_extent_allocation_hint(struct inode *inode, u64 start,
935 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
936 struct extent_map *em;
939 read_lock(&em_tree->lock);
940 em = search_extent_mapping(em_tree, start, num_bytes);
943 * if block start isn't an actual block number then find the
944 * first block in this inode and use that as a hint. If that
945 * block is also bogus then just don't worry about it.
947 if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
949 em = search_extent_mapping(em_tree, 0, 0);
950 if (em && em->block_start < EXTENT_MAP_LAST_BYTE)
951 alloc_hint = em->block_start;
955 alloc_hint = em->block_start;
959 read_unlock(&em_tree->lock);
965 * when extent_io.c finds a delayed allocation range in the file,
966 * the call backs end up in this code. The basic idea is to
967 * allocate extents on disk for the range, and create ordered data structs
968 * in ram to track those extents.
970 * locked_page is the page that writepage had locked already. We use
971 * it to make sure we don't do extra locks or unlocks.
973 * *page_started is set to one if we unlock locked_page and do everything
974 * required to start IO on it. It may be clean and already done with
977 static noinline int cow_file_range(struct inode *inode,
978 struct page *locked_page,
979 u64 start, u64 end, int *page_started,
980 unsigned long *nr_written, int unlock)
982 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
983 struct btrfs_root *root = BTRFS_I(inode)->root;
986 unsigned long ram_size;
987 u64 cur_alloc_size = 0;
989 u64 blocksize = fs_info->sectorsize;
990 struct btrfs_key ins;
991 struct extent_map *em;
993 unsigned long page_ops;
994 bool extent_reserved = false;
997 if (btrfs_is_free_space_inode(BTRFS_I(inode))) {
1003 num_bytes = ALIGN(end - start + 1, blocksize);
1004 num_bytes = max(blocksize, num_bytes);
1005 ASSERT(num_bytes <= btrfs_super_total_bytes(fs_info->super_copy));
1007 inode_should_defrag(BTRFS_I(inode), start, end, num_bytes, SZ_64K);
1010 /* lets try to make an inline extent */
1011 ret = cow_file_range_inline(inode, start, end, 0,
1012 BTRFS_COMPRESS_NONE, NULL);
1015 * We use DO_ACCOUNTING here because we need the
1016 * delalloc_release_metadata to be run _after_ we drop
1017 * our outstanding extent for clearing delalloc for this
1020 extent_clear_unlock_delalloc(inode, start, end, NULL,
1021 EXTENT_LOCKED | EXTENT_DELALLOC |
1022 EXTENT_DELALLOC_NEW | EXTENT_DEFRAG |
1023 EXTENT_DO_ACCOUNTING, PAGE_UNLOCK |
1024 PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK |
1025 PAGE_END_WRITEBACK);
1026 *nr_written = *nr_written +
1027 (end - start + PAGE_SIZE) / PAGE_SIZE;
1030 } else if (ret < 0) {
1035 alloc_hint = get_extent_allocation_hint(inode, start, num_bytes);
1036 btrfs_drop_extent_cache(BTRFS_I(inode), start,
1037 start + num_bytes - 1, 0);
1040 * Relocation relies on the relocated extents to have exactly the same
1041 * size as the original extents. Normally writeback for relocation data
1042 * extents follows a NOCOW path because relocation preallocates the
1043 * extents. However, due to an operation such as scrub turning a block
1044 * group to RO mode, it may fallback to COW mode, so we must make sure
1045 * an extent allocated during COW has exactly the requested size and can
1046 * not be split into smaller extents, otherwise relocation breaks and
1047 * fails during the stage where it updates the bytenr of file extent
1050 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
1051 min_alloc_size = num_bytes;
1053 min_alloc_size = fs_info->sectorsize;
1055 while (num_bytes > 0) {
1056 cur_alloc_size = num_bytes;
1057 ret = btrfs_reserve_extent(root, cur_alloc_size, cur_alloc_size,
1058 min_alloc_size, 0, alloc_hint,
1062 cur_alloc_size = ins.offset;
1063 extent_reserved = true;
1065 ram_size = ins.offset;
1066 em = create_io_em(inode, start, ins.offset, /* len */
1067 start, /* orig_start */
1068 ins.objectid, /* block_start */
1069 ins.offset, /* block_len */
1070 ins.offset, /* orig_block_len */
1071 ram_size, /* ram_bytes */
1072 BTRFS_COMPRESS_NONE, /* compress_type */
1073 BTRFS_ORDERED_REGULAR /* type */);
1078 free_extent_map(em);
1080 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
1081 ram_size, cur_alloc_size, 0);
1083 goto out_drop_extent_cache;
1085 if (root->root_key.objectid ==
1086 BTRFS_DATA_RELOC_TREE_OBJECTID) {
1087 ret = btrfs_reloc_clone_csums(inode, start,
1090 * Only drop cache here, and process as normal.
1092 * We must not allow extent_clear_unlock_delalloc()
1093 * at out_unlock label to free meta of this ordered
1094 * extent, as its meta should be freed by
1095 * btrfs_finish_ordered_io().
1097 * So we must continue until @start is increased to
1098 * skip current ordered extent.
1101 btrfs_drop_extent_cache(BTRFS_I(inode), start,
1102 start + ram_size - 1, 0);
1105 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
1107 /* we're not doing compressed IO, don't unlock the first
1108 * page (which the caller expects to stay locked), don't
1109 * clear any dirty bits and don't set any writeback bits
1111 * Do set the Private2 bit so we know this page was properly
1112 * setup for writepage
1114 page_ops = unlock ? PAGE_UNLOCK : 0;
1115 page_ops |= PAGE_SET_PRIVATE2;
1117 extent_clear_unlock_delalloc(inode, start,
1118 start + ram_size - 1,
1120 EXTENT_LOCKED | EXTENT_DELALLOC,
1122 if (num_bytes < cur_alloc_size)
1125 num_bytes -= cur_alloc_size;
1126 alloc_hint = ins.objectid + ins.offset;
1127 start += cur_alloc_size;
1128 extent_reserved = false;
1131 * btrfs_reloc_clone_csums() error, since start is increased
1132 * extent_clear_unlock_delalloc() at out_unlock label won't
1133 * free metadata of current ordered extent, we're OK to exit.
1141 out_drop_extent_cache:
1142 btrfs_drop_extent_cache(BTRFS_I(inode), start, start + ram_size - 1, 0);
1144 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
1145 btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1);
1147 clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW |
1148 EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV;
1149 page_ops = PAGE_UNLOCK | PAGE_CLEAR_DIRTY | PAGE_SET_WRITEBACK |
1152 * If we reserved an extent for our delalloc range (or a subrange) and
1153 * failed to create the respective ordered extent, then it means that
1154 * when we reserved the extent we decremented the extent's size from
1155 * the data space_info's bytes_may_use counter and incremented the
1156 * space_info's bytes_reserved counter by the same amount. We must make
1157 * sure extent_clear_unlock_delalloc() does not try to decrement again
1158 * the data space_info's bytes_may_use counter, therefore we do not pass
1159 * it the flag EXTENT_CLEAR_DATA_RESV.
1161 if (extent_reserved) {
1162 extent_clear_unlock_delalloc(inode, start,
1163 start + cur_alloc_size - 1,
1167 start += cur_alloc_size;
1171 extent_clear_unlock_delalloc(inode, start, end, locked_page,
1172 clear_bits | EXTENT_CLEAR_DATA_RESV,
1178 * work queue call back to started compression on a file and pages
1180 static noinline void async_cow_start(struct btrfs_work *work)
1182 struct async_chunk *async_chunk;
1183 int compressed_extents;
1185 async_chunk = container_of(work, struct async_chunk, work);
1187 compressed_extents = compress_file_range(async_chunk);
1188 if (compressed_extents == 0) {
1189 btrfs_add_delayed_iput(async_chunk->inode);
1190 async_chunk->inode = NULL;
1195 * work queue call back to submit previously compressed pages
1197 static noinline void async_cow_submit(struct btrfs_work *work)
1199 struct async_chunk *async_chunk = container_of(work, struct async_chunk,
1201 struct btrfs_fs_info *fs_info = btrfs_work_owner(work);
1202 unsigned long nr_pages;
1204 nr_pages = (async_chunk->end - async_chunk->start + PAGE_SIZE) >>
1207 /* atomic_sub_return implies a barrier */
1208 if (atomic_sub_return(nr_pages, &fs_info->async_delalloc_pages) <
1210 cond_wake_up_nomb(&fs_info->async_submit_wait);
1213 * ->inode could be NULL if async_chunk_start has failed to compress,
1214 * in which case we don't have anything to submit, yet we need to
1215 * always adjust ->async_delalloc_pages as its paired with the init
1216 * happening in cow_file_range_async
1218 if (async_chunk->inode)
1219 submit_compressed_extents(async_chunk);
1222 static noinline void async_cow_free(struct btrfs_work *work)
1224 struct async_chunk *async_chunk;
1226 async_chunk = container_of(work, struct async_chunk, work);
1227 if (async_chunk->inode)
1228 btrfs_add_delayed_iput(async_chunk->inode);
1229 if (async_chunk->blkcg_css)
1230 css_put(async_chunk->blkcg_css);
1232 * Since the pointer to 'pending' is at the beginning of the array of
1233 * async_chunk's, freeing it ensures the whole array has been freed.
1235 if (atomic_dec_and_test(async_chunk->pending))
1236 kvfree(async_chunk->pending);
1239 static int cow_file_range_async(struct inode *inode,
1240 struct writeback_control *wbc,
1241 struct page *locked_page,
1242 u64 start, u64 end, int *page_started,
1243 unsigned long *nr_written)
1245 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1246 struct cgroup_subsys_state *blkcg_css = wbc_blkcg_css(wbc);
1247 struct async_cow *ctx;
1248 struct async_chunk *async_chunk;
1249 unsigned long nr_pages;
1251 u64 num_chunks = DIV_ROUND_UP(end - start, SZ_512K);
1253 bool should_compress;
1255 const unsigned int write_flags = wbc_to_write_flags(wbc);
1257 unlock_extent(&BTRFS_I(inode)->io_tree, start, end);
1259 if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS &&
1260 !btrfs_test_opt(fs_info, FORCE_COMPRESS)) {
1262 should_compress = false;
1264 should_compress = true;
1267 nofs_flag = memalloc_nofs_save();
1268 ctx = kvmalloc(struct_size(ctx, chunks, num_chunks), GFP_KERNEL);
1269 memalloc_nofs_restore(nofs_flag);
1272 unsigned clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC |
1273 EXTENT_DELALLOC_NEW | EXTENT_DEFRAG |
1274 EXTENT_DO_ACCOUNTING;
1275 unsigned long page_ops = PAGE_UNLOCK | PAGE_CLEAR_DIRTY |
1276 PAGE_SET_WRITEBACK | PAGE_END_WRITEBACK |
1279 extent_clear_unlock_delalloc(inode, start, end, locked_page,
1280 clear_bits, page_ops);
1284 async_chunk = ctx->chunks;
1285 atomic_set(&ctx->num_chunks, num_chunks);
1287 for (i = 0; i < num_chunks; i++) {
1288 if (should_compress)
1289 cur_end = min(end, start + SZ_512K - 1);
1294 * igrab is called higher up in the call chain, take only the
1295 * lightweight reference for the callback lifetime
1298 async_chunk[i].pending = &ctx->num_chunks;
1299 async_chunk[i].inode = inode;
1300 async_chunk[i].start = start;
1301 async_chunk[i].end = cur_end;
1302 async_chunk[i].write_flags = write_flags;
1303 INIT_LIST_HEAD(&async_chunk[i].extents);
1306 * The locked_page comes all the way from writepage and its
1307 * the original page we were actually given. As we spread
1308 * this large delalloc region across multiple async_chunk
1309 * structs, only the first struct needs a pointer to locked_page
1311 * This way we don't need racey decisions about who is supposed
1316 * Depending on the compressibility, the pages might or
1317 * might not go through async. We want all of them to
1318 * be accounted against wbc once. Let's do it here
1319 * before the paths diverge. wbc accounting is used
1320 * only for foreign writeback detection and doesn't
1321 * need full accuracy. Just account the whole thing
1322 * against the first page.
1324 wbc_account_cgroup_owner(wbc, locked_page,
1326 async_chunk[i].locked_page = locked_page;
1329 async_chunk[i].locked_page = NULL;
1332 if (blkcg_css != blkcg_root_css) {
1334 async_chunk[i].blkcg_css = blkcg_css;
1336 async_chunk[i].blkcg_css = NULL;
1339 btrfs_init_work(&async_chunk[i].work, async_cow_start,
1340 async_cow_submit, async_cow_free);
1342 nr_pages = DIV_ROUND_UP(cur_end - start, PAGE_SIZE);
1343 atomic_add(nr_pages, &fs_info->async_delalloc_pages);
1345 btrfs_queue_work(fs_info->delalloc_workers, &async_chunk[i].work);
1347 *nr_written += nr_pages;
1348 start = cur_end + 1;
1354 static noinline int csum_exist_in_range(struct btrfs_fs_info *fs_info,
1355 u64 bytenr, u64 num_bytes)
1358 struct btrfs_ordered_sum *sums;
1361 ret = btrfs_lookup_csums_range(fs_info->csum_root, bytenr,
1362 bytenr + num_bytes - 1, &list, 0);
1363 if (ret == 0 && list_empty(&list))
1366 while (!list_empty(&list)) {
1367 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
1368 list_del(&sums->list);
1376 static int fallback_to_cow(struct inode *inode, struct page *locked_page,
1377 const u64 start, const u64 end,
1378 int *page_started, unsigned long *nr_written)
1380 const bool is_space_ino = btrfs_is_free_space_inode(BTRFS_I(inode));
1381 const u64 range_bytes = end + 1 - start;
1382 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1383 u64 range_start = start;
1387 * If EXTENT_NORESERVE is set it means that when the buffered write was
1388 * made we had not enough available data space and therefore we did not
1389 * reserve data space for it, since we though we could do NOCOW for the
1390 * respective file range (either there is prealloc extent or the inode
1391 * has the NOCOW bit set).
1393 * However when we need to fallback to COW mode (because for example the
1394 * block group for the corresponding extent was turned to RO mode by a
1395 * scrub or relocation) we need to do the following:
1397 * 1) We increment the bytes_may_use counter of the data space info.
1398 * If COW succeeds, it allocates a new data extent and after doing
1399 * that it decrements the space info's bytes_may_use counter and
1400 * increments its bytes_reserved counter by the same amount (we do
1401 * this at btrfs_add_reserved_bytes()). So we need to increment the
1402 * bytes_may_use counter to compensate (when space is reserved at
1403 * buffered write time, the bytes_may_use counter is incremented);
1405 * 2) We clear the EXTENT_NORESERVE bit from the range. We do this so
1406 * that if the COW path fails for any reason, it decrements (through
1407 * extent_clear_unlock_delalloc()) the bytes_may_use counter of the
1408 * data space info, which we incremented in the step above.
1410 * If we need to fallback to cow and the inode corresponds to a free
1411 * space cache inode, we must also increment bytes_may_use of the data
1412 * space_info for the same reason. Space caches always get a prealloc
1413 * extent for them, however scrub or balance may have set the block
1414 * group that contains that extent to RO mode.
1416 count = count_range_bits(io_tree, &range_start, end, range_bytes,
1417 EXTENT_NORESERVE, 0);
1418 if (count > 0 || is_space_ino) {
1419 const u64 bytes = is_space_ino ? range_bytes : count;
1420 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
1421 struct btrfs_space_info *sinfo = fs_info->data_sinfo;
1423 spin_lock(&sinfo->lock);
1424 btrfs_space_info_update_bytes_may_use(fs_info, sinfo, bytes);
1425 spin_unlock(&sinfo->lock);
1428 clear_extent_bit(io_tree, start, end, EXTENT_NORESERVE,
1432 return cow_file_range(inode, locked_page, start, end, page_started,
1437 * when nowcow writeback call back. This checks for snapshots or COW copies
1438 * of the extents that exist in the file, and COWs the file as required.
1440 * If no cow copies or snapshots exist, we write directly to the existing
1443 static noinline int run_delalloc_nocow(struct inode *inode,
1444 struct page *locked_page,
1445 const u64 start, const u64 end,
1446 int *page_started, int force,
1447 unsigned long *nr_written)
1449 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1450 struct btrfs_root *root = BTRFS_I(inode)->root;
1451 struct btrfs_path *path;
1452 u64 cow_start = (u64)-1;
1453 u64 cur_offset = start;
1455 bool check_prev = true;
1456 const bool freespace_inode = btrfs_is_free_space_inode(BTRFS_I(inode));
1457 u64 ino = btrfs_ino(BTRFS_I(inode));
1459 u64 disk_bytenr = 0;
1461 path = btrfs_alloc_path();
1463 extent_clear_unlock_delalloc(inode, start, end, locked_page,
1464 EXTENT_LOCKED | EXTENT_DELALLOC |
1465 EXTENT_DO_ACCOUNTING |
1466 EXTENT_DEFRAG, PAGE_UNLOCK |
1468 PAGE_SET_WRITEBACK |
1469 PAGE_END_WRITEBACK);
1474 struct btrfs_key found_key;
1475 struct btrfs_file_extent_item *fi;
1476 struct extent_buffer *leaf;
1486 ret = btrfs_lookup_file_extent(NULL, root, path, ino,
1492 * If there is no extent for our range when doing the initial
1493 * search, then go back to the previous slot as it will be the
1494 * one containing the search offset
1496 if (ret > 0 && path->slots[0] > 0 && check_prev) {
1497 leaf = path->nodes[0];
1498 btrfs_item_key_to_cpu(leaf, &found_key,
1499 path->slots[0] - 1);
1500 if (found_key.objectid == ino &&
1501 found_key.type == BTRFS_EXTENT_DATA_KEY)
1506 /* Go to next leaf if we have exhausted the current one */
1507 leaf = path->nodes[0];
1508 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1509 ret = btrfs_next_leaf(root, path);
1511 if (cow_start != (u64)-1)
1512 cur_offset = cow_start;
1517 leaf = path->nodes[0];
1520 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1522 /* Didn't find anything for our INO */
1523 if (found_key.objectid > ino)
1526 * Keep searching until we find an EXTENT_ITEM or there are no
1527 * more extents for this inode
1529 if (WARN_ON_ONCE(found_key.objectid < ino) ||
1530 found_key.type < BTRFS_EXTENT_DATA_KEY) {
1535 /* Found key is not EXTENT_DATA_KEY or starts after req range */
1536 if (found_key.type > BTRFS_EXTENT_DATA_KEY ||
1537 found_key.offset > end)
1541 * If the found extent starts after requested offset, then
1542 * adjust extent_end to be right before this extent begins
1544 if (found_key.offset > cur_offset) {
1545 extent_end = found_key.offset;
1551 * Found extent which begins before our range and potentially
1554 fi = btrfs_item_ptr(leaf, path->slots[0],
1555 struct btrfs_file_extent_item);
1556 extent_type = btrfs_file_extent_type(leaf, fi);
1558 ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
1559 if (extent_type == BTRFS_FILE_EXTENT_REG ||
1560 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1561 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1562 extent_offset = btrfs_file_extent_offset(leaf, fi);
1563 extent_end = found_key.offset +
1564 btrfs_file_extent_num_bytes(leaf, fi);
1566 btrfs_file_extent_disk_num_bytes(leaf, fi);
1568 * If the extent we got ends before our current offset,
1569 * skip to the next extent.
1571 if (extent_end <= cur_offset) {
1576 if (disk_bytenr == 0)
1578 /* Skip compressed/encrypted/encoded extents */
1579 if (btrfs_file_extent_compression(leaf, fi) ||
1580 btrfs_file_extent_encryption(leaf, fi) ||
1581 btrfs_file_extent_other_encoding(leaf, fi))
1584 * If extent is created before the last volume's snapshot
1585 * this implies the extent is shared, hence we can't do
1586 * nocow. This is the same check as in
1587 * btrfs_cross_ref_exist but without calling
1588 * btrfs_search_slot.
1590 if (!freespace_inode &&
1591 btrfs_file_extent_generation(leaf, fi) <=
1592 btrfs_root_last_snapshot(&root->root_item))
1594 if (extent_type == BTRFS_FILE_EXTENT_REG && !force)
1596 /* If extent is RO, we must COW it */
1597 if (btrfs_extent_readonly(fs_info, disk_bytenr))
1599 ret = btrfs_cross_ref_exist(root, ino,
1601 extent_offset, disk_bytenr);
1604 * ret could be -EIO if the above fails to read
1608 if (cow_start != (u64)-1)
1609 cur_offset = cow_start;
1613 WARN_ON_ONCE(freespace_inode);
1616 disk_bytenr += extent_offset;
1617 disk_bytenr += cur_offset - found_key.offset;
1618 num_bytes = min(end + 1, extent_end) - cur_offset;
1620 * If there are pending snapshots for this root, we
1621 * fall into common COW way
1623 if (!freespace_inode && atomic_read(&root->snapshot_force_cow))
1626 * force cow if csum exists in the range.
1627 * this ensure that csum for a given extent are
1628 * either valid or do not exist.
1630 ret = csum_exist_in_range(fs_info, disk_bytenr,
1634 * ret could be -EIO if the above fails to read
1638 if (cow_start != (u64)-1)
1639 cur_offset = cow_start;
1642 WARN_ON_ONCE(freespace_inode);
1645 if (!btrfs_inc_nocow_writers(fs_info, disk_bytenr))
1648 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1649 extent_end = found_key.offset + ram_bytes;
1650 extent_end = ALIGN(extent_end, fs_info->sectorsize);
1651 /* Skip extents outside of our requested range */
1652 if (extent_end <= start) {
1657 /* If this triggers then we have a memory corruption */
1662 * If nocow is false then record the beginning of the range
1663 * that needs to be COWed
1666 if (cow_start == (u64)-1)
1667 cow_start = cur_offset;
1668 cur_offset = extent_end;
1669 if (cur_offset > end)
1675 btrfs_release_path(path);
1678 * COW range from cow_start to found_key.offset - 1. As the key
1679 * will contain the beginning of the first extent that can be
1680 * NOCOW, following one which needs to be COW'ed
1682 if (cow_start != (u64)-1) {
1683 ret = fallback_to_cow(inode, locked_page, cow_start,
1684 found_key.offset - 1,
1685 page_started, nr_written);
1688 btrfs_dec_nocow_writers(fs_info,
1692 cow_start = (u64)-1;
1695 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
1696 u64 orig_start = found_key.offset - extent_offset;
1697 struct extent_map *em;
1699 em = create_io_em(inode, cur_offset, num_bytes,
1701 disk_bytenr, /* block_start */
1702 num_bytes, /* block_len */
1703 disk_num_bytes, /* orig_block_len */
1704 ram_bytes, BTRFS_COMPRESS_NONE,
1705 BTRFS_ORDERED_PREALLOC);
1708 btrfs_dec_nocow_writers(fs_info,
1713 free_extent_map(em);
1714 ret = btrfs_add_ordered_extent(inode, cur_offset,
1715 disk_bytenr, num_bytes,
1717 BTRFS_ORDERED_PREALLOC);
1719 btrfs_drop_extent_cache(BTRFS_I(inode),
1721 cur_offset + num_bytes - 1,
1726 ret = btrfs_add_ordered_extent(inode, cur_offset,
1727 disk_bytenr, num_bytes,
1729 BTRFS_ORDERED_NOCOW);
1735 btrfs_dec_nocow_writers(fs_info, disk_bytenr);
1738 if (root->root_key.objectid ==
1739 BTRFS_DATA_RELOC_TREE_OBJECTID)
1741 * Error handled later, as we must prevent
1742 * extent_clear_unlock_delalloc() in error handler
1743 * from freeing metadata of created ordered extent.
1745 ret = btrfs_reloc_clone_csums(inode, cur_offset,
1748 extent_clear_unlock_delalloc(inode, cur_offset,
1749 cur_offset + num_bytes - 1,
1750 locked_page, EXTENT_LOCKED |
1752 EXTENT_CLEAR_DATA_RESV,
1753 PAGE_UNLOCK | PAGE_SET_PRIVATE2);
1755 cur_offset = extent_end;
1758 * btrfs_reloc_clone_csums() error, now we're OK to call error
1759 * handler, as metadata for created ordered extent will only
1760 * be freed by btrfs_finish_ordered_io().
1764 if (cur_offset > end)
1767 btrfs_release_path(path);
1769 if (cur_offset <= end && cow_start == (u64)-1)
1770 cow_start = cur_offset;
1772 if (cow_start != (u64)-1) {
1774 ret = fallback_to_cow(inode, locked_page, cow_start, end,
1775 page_started, nr_written);
1782 btrfs_dec_nocow_writers(fs_info, disk_bytenr);
1784 if (ret && cur_offset < end)
1785 extent_clear_unlock_delalloc(inode, cur_offset, end,
1786 locked_page, EXTENT_LOCKED |
1787 EXTENT_DELALLOC | EXTENT_DEFRAG |
1788 EXTENT_DO_ACCOUNTING, PAGE_UNLOCK |
1790 PAGE_SET_WRITEBACK |
1791 PAGE_END_WRITEBACK);
1792 btrfs_free_path(path);
1796 static inline int need_force_cow(struct inode *inode, u64 start, u64 end)
1799 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
1800 !(BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC))
1804 * @defrag_bytes is a hint value, no spinlock held here,
1805 * if is not zero, it means the file is defragging.
1806 * Force cow if given extent needs to be defragged.
1808 if (BTRFS_I(inode)->defrag_bytes &&
1809 test_range_bit(&BTRFS_I(inode)->io_tree, start, end,
1810 EXTENT_DEFRAG, 0, NULL))
1817 * Function to process delayed allocation (create CoW) for ranges which are
1818 * being touched for the first time.
1820 int btrfs_run_delalloc_range(struct inode *inode, struct page *locked_page,
1821 u64 start, u64 end, int *page_started, unsigned long *nr_written,
1822 struct writeback_control *wbc)
1825 int force_cow = need_force_cow(inode, start, end);
1827 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW && !force_cow) {
1828 ret = run_delalloc_nocow(inode, locked_page, start, end,
1829 page_started, 1, nr_written);
1830 } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC && !force_cow) {
1831 ret = run_delalloc_nocow(inode, locked_page, start, end,
1832 page_started, 0, nr_written);
1833 } else if (!inode_can_compress(inode) ||
1834 !inode_need_compress(inode, start, end)) {
1835 ret = cow_file_range(inode, locked_page, start, end,
1836 page_started, nr_written, 1);
1838 set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1839 &BTRFS_I(inode)->runtime_flags);
1840 ret = cow_file_range_async(inode, wbc, locked_page, start, end,
1841 page_started, nr_written);
1844 btrfs_cleanup_ordered_extents(inode, locked_page, start,
1849 void btrfs_split_delalloc_extent(struct inode *inode,
1850 struct extent_state *orig, u64 split)
1854 /* not delalloc, ignore it */
1855 if (!(orig->state & EXTENT_DELALLOC))
1858 size = orig->end - orig->start + 1;
1859 if (size > BTRFS_MAX_EXTENT_SIZE) {
1864 * See the explanation in btrfs_merge_delalloc_extent, the same
1865 * applies here, just in reverse.
1867 new_size = orig->end - split + 1;
1868 num_extents = count_max_extents(new_size);
1869 new_size = split - orig->start;
1870 num_extents += count_max_extents(new_size);
1871 if (count_max_extents(size) >= num_extents)
1875 spin_lock(&BTRFS_I(inode)->lock);
1876 btrfs_mod_outstanding_extents(BTRFS_I(inode), 1);
1877 spin_unlock(&BTRFS_I(inode)->lock);
1881 * Handle merged delayed allocation extents so we can keep track of new extents
1882 * that are just merged onto old extents, such as when we are doing sequential
1883 * writes, so we can properly account for the metadata space we'll need.
1885 void btrfs_merge_delalloc_extent(struct inode *inode, struct extent_state *new,
1886 struct extent_state *other)
1888 u64 new_size, old_size;
1891 /* not delalloc, ignore it */
1892 if (!(other->state & EXTENT_DELALLOC))
1895 if (new->start > other->start)
1896 new_size = new->end - other->start + 1;
1898 new_size = other->end - new->start + 1;
1900 /* we're not bigger than the max, unreserve the space and go */
1901 if (new_size <= BTRFS_MAX_EXTENT_SIZE) {
1902 spin_lock(&BTRFS_I(inode)->lock);
1903 btrfs_mod_outstanding_extents(BTRFS_I(inode), -1);
1904 spin_unlock(&BTRFS_I(inode)->lock);
1909 * We have to add up either side to figure out how many extents were
1910 * accounted for before we merged into one big extent. If the number of
1911 * extents we accounted for is <= the amount we need for the new range
1912 * then we can return, otherwise drop. Think of it like this
1916 * So we've grown the extent by a MAX_SIZE extent, this would mean we
1917 * need 2 outstanding extents, on one side we have 1 and the other side
1918 * we have 1 so they are == and we can return. But in this case
1920 * [MAX_SIZE+4k][MAX_SIZE+4k]
1922 * Each range on their own accounts for 2 extents, but merged together
1923 * they are only 3 extents worth of accounting, so we need to drop in
1926 old_size = other->end - other->start + 1;
1927 num_extents = count_max_extents(old_size);
1928 old_size = new->end - new->start + 1;
1929 num_extents += count_max_extents(old_size);
1930 if (count_max_extents(new_size) >= num_extents)
1933 spin_lock(&BTRFS_I(inode)->lock);
1934 btrfs_mod_outstanding_extents(BTRFS_I(inode), -1);
1935 spin_unlock(&BTRFS_I(inode)->lock);
1938 static void btrfs_add_delalloc_inodes(struct btrfs_root *root,
1939 struct inode *inode)
1941 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1943 spin_lock(&root->delalloc_lock);
1944 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
1945 list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
1946 &root->delalloc_inodes);
1947 set_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1948 &BTRFS_I(inode)->runtime_flags);
1949 root->nr_delalloc_inodes++;
1950 if (root->nr_delalloc_inodes == 1) {
1951 spin_lock(&fs_info->delalloc_root_lock);
1952 BUG_ON(!list_empty(&root->delalloc_root));
1953 list_add_tail(&root->delalloc_root,
1954 &fs_info->delalloc_roots);
1955 spin_unlock(&fs_info->delalloc_root_lock);
1958 spin_unlock(&root->delalloc_lock);
1962 void __btrfs_del_delalloc_inode(struct btrfs_root *root,
1963 struct btrfs_inode *inode)
1965 struct btrfs_fs_info *fs_info = root->fs_info;
1967 if (!list_empty(&inode->delalloc_inodes)) {
1968 list_del_init(&inode->delalloc_inodes);
1969 clear_bit(BTRFS_INODE_IN_DELALLOC_LIST,
1970 &inode->runtime_flags);
1971 root->nr_delalloc_inodes--;
1972 if (!root->nr_delalloc_inodes) {
1973 ASSERT(list_empty(&root->delalloc_inodes));
1974 spin_lock(&fs_info->delalloc_root_lock);
1975 BUG_ON(list_empty(&root->delalloc_root));
1976 list_del_init(&root->delalloc_root);
1977 spin_unlock(&fs_info->delalloc_root_lock);
1982 static void btrfs_del_delalloc_inode(struct btrfs_root *root,
1983 struct btrfs_inode *inode)
1985 spin_lock(&root->delalloc_lock);
1986 __btrfs_del_delalloc_inode(root, inode);
1987 spin_unlock(&root->delalloc_lock);
1991 * Properly track delayed allocation bytes in the inode and to maintain the
1992 * list of inodes that have pending delalloc work to be done.
1994 void btrfs_set_delalloc_extent(struct inode *inode, struct extent_state *state,
1997 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1999 if ((*bits & EXTENT_DEFRAG) && !(*bits & EXTENT_DELALLOC))
2002 * set_bit and clear bit hooks normally require _irqsave/restore
2003 * but in this case, we are only testing for the DELALLOC
2004 * bit, which is only set or cleared with irqs on
2006 if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
2007 struct btrfs_root *root = BTRFS_I(inode)->root;
2008 u64 len = state->end + 1 - state->start;
2009 u32 num_extents = count_max_extents(len);
2010 bool do_list = !btrfs_is_free_space_inode(BTRFS_I(inode));
2012 spin_lock(&BTRFS_I(inode)->lock);
2013 btrfs_mod_outstanding_extents(BTRFS_I(inode), num_extents);
2014 spin_unlock(&BTRFS_I(inode)->lock);
2016 /* For sanity tests */
2017 if (btrfs_is_testing(fs_info))
2020 percpu_counter_add_batch(&fs_info->delalloc_bytes, len,
2021 fs_info->delalloc_batch);
2022 spin_lock(&BTRFS_I(inode)->lock);
2023 BTRFS_I(inode)->delalloc_bytes += len;
2024 if (*bits & EXTENT_DEFRAG)
2025 BTRFS_I(inode)->defrag_bytes += len;
2026 if (do_list && !test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
2027 &BTRFS_I(inode)->runtime_flags))
2028 btrfs_add_delalloc_inodes(root, inode);
2029 spin_unlock(&BTRFS_I(inode)->lock);
2032 if (!(state->state & EXTENT_DELALLOC_NEW) &&
2033 (*bits & EXTENT_DELALLOC_NEW)) {
2034 spin_lock(&BTRFS_I(inode)->lock);
2035 BTRFS_I(inode)->new_delalloc_bytes += state->end + 1 -
2037 spin_unlock(&BTRFS_I(inode)->lock);
2042 * Once a range is no longer delalloc this function ensures that proper
2043 * accounting happens.
2045 void btrfs_clear_delalloc_extent(struct inode *vfs_inode,
2046 struct extent_state *state, unsigned *bits)
2048 struct btrfs_inode *inode = BTRFS_I(vfs_inode);
2049 struct btrfs_fs_info *fs_info = btrfs_sb(vfs_inode->i_sb);
2050 u64 len = state->end + 1 - state->start;
2051 u32 num_extents = count_max_extents(len);
2053 if ((state->state & EXTENT_DEFRAG) && (*bits & EXTENT_DEFRAG)) {
2054 spin_lock(&inode->lock);
2055 inode->defrag_bytes -= len;
2056 spin_unlock(&inode->lock);
2060 * set_bit and clear bit hooks normally require _irqsave/restore
2061 * but in this case, we are only testing for the DELALLOC
2062 * bit, which is only set or cleared with irqs on
2064 if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) {
2065 struct btrfs_root *root = inode->root;
2066 bool do_list = !btrfs_is_free_space_inode(inode);
2068 spin_lock(&inode->lock);
2069 btrfs_mod_outstanding_extents(inode, -num_extents);
2070 spin_unlock(&inode->lock);
2073 * We don't reserve metadata space for space cache inodes so we
2074 * don't need to call delalloc_release_metadata if there is an
2077 if (*bits & EXTENT_CLEAR_META_RESV &&
2078 root != fs_info->tree_root)
2079 btrfs_delalloc_release_metadata(inode, len, false);
2081 /* For sanity tests. */
2082 if (btrfs_is_testing(fs_info))
2085 if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID &&
2086 do_list && !(state->state & EXTENT_NORESERVE) &&
2087 (*bits & EXTENT_CLEAR_DATA_RESV))
2088 btrfs_free_reserved_data_space_noquota(
2092 percpu_counter_add_batch(&fs_info->delalloc_bytes, -len,
2093 fs_info->delalloc_batch);
2094 spin_lock(&inode->lock);
2095 inode->delalloc_bytes -= len;
2096 if (do_list && inode->delalloc_bytes == 0 &&
2097 test_bit(BTRFS_INODE_IN_DELALLOC_LIST,
2098 &inode->runtime_flags))
2099 btrfs_del_delalloc_inode(root, inode);
2100 spin_unlock(&inode->lock);
2103 if ((state->state & EXTENT_DELALLOC_NEW) &&
2104 (*bits & EXTENT_DELALLOC_NEW)) {
2105 spin_lock(&inode->lock);
2106 ASSERT(inode->new_delalloc_bytes >= len);
2107 inode->new_delalloc_bytes -= len;
2108 spin_unlock(&inode->lock);
2113 * btrfs_bio_fits_in_stripe - Checks whether the size of the given bio will fit
2114 * in a chunk's stripe. This function ensures that bios do not span a
2117 * @page - The page we are about to add to the bio
2118 * @size - size we want to add to the bio
2119 * @bio - bio we want to ensure is smaller than a stripe
2120 * @bio_flags - flags of the bio
2122 * return 1 if page cannot be added to the bio
2123 * return 0 if page can be added to the bio
2124 * return error otherwise
2126 int btrfs_bio_fits_in_stripe(struct page *page, size_t size, struct bio *bio,
2127 unsigned long bio_flags)
2129 struct inode *inode = page->mapping->host;
2130 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2131 u64 logical = (u64)bio->bi_iter.bi_sector << 9;
2135 struct btrfs_io_geometry geom;
2137 if (bio_flags & EXTENT_BIO_COMPRESSED)
2140 length = bio->bi_iter.bi_size;
2141 map_length = length;
2142 ret = btrfs_get_io_geometry(fs_info, btrfs_op(bio), logical, map_length,
2147 if (geom.len < length + size)
2153 * in order to insert checksums into the metadata in large chunks,
2154 * we wait until bio submission time. All the pages in the bio are
2155 * checksummed and sums are attached onto the ordered extent record.
2157 * At IO completion time the cums attached on the ordered extent record
2158 * are inserted into the btree
2160 static blk_status_t btrfs_submit_bio_start(void *private_data, struct bio *bio,
2163 struct inode *inode = private_data;
2164 blk_status_t ret = 0;
2166 ret = btrfs_csum_one_bio(inode, bio, 0, 0);
2167 BUG_ON(ret); /* -ENOMEM */
2172 * extent_io.c submission hook. This does the right thing for csum calculation
2173 * on write, or reading the csums from the tree before a read.
2175 * Rules about async/sync submit,
2176 * a) read: sync submit
2178 * b) write without checksum: sync submit
2180 * c) write with checksum:
2181 * c-1) if bio is issued by fsync: sync submit
2182 * (sync_writers != 0)
2184 * c-2) if root is reloc root: sync submit
2185 * (only in case of buffered IO)
2187 * c-3) otherwise: async submit
2189 static blk_status_t btrfs_submit_bio_hook(struct inode *inode, struct bio *bio,
2191 unsigned long bio_flags)
2194 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2195 struct btrfs_root *root = BTRFS_I(inode)->root;
2196 enum btrfs_wq_endio_type metadata = BTRFS_WQ_ENDIO_DATA;
2197 blk_status_t ret = 0;
2199 int async = !atomic_read(&BTRFS_I(inode)->sync_writers);
2201 skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
2203 if (btrfs_is_free_space_inode(BTRFS_I(inode)))
2204 metadata = BTRFS_WQ_ENDIO_FREE_SPACE;
2206 if (bio_op(bio) != REQ_OP_WRITE) {
2207 ret = btrfs_bio_wq_end_io(fs_info, bio, metadata);
2211 if (bio_flags & EXTENT_BIO_COMPRESSED) {
2212 ret = btrfs_submit_compressed_read(inode, bio,
2216 } else if (!skip_sum) {
2217 ret = btrfs_lookup_bio_sums(inode, bio, (u64)-1, NULL);
2222 } else if (async && !skip_sum) {
2223 /* csum items have already been cloned */
2224 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID)
2226 /* we're doing a write, do the async checksumming */
2227 ret = btrfs_wq_submit_bio(fs_info, bio, mirror_num, bio_flags,
2228 0, inode, btrfs_submit_bio_start);
2230 } else if (!skip_sum) {
2231 ret = btrfs_csum_one_bio(inode, bio, 0, 0);
2237 ret = btrfs_map_bio(fs_info, bio, mirror_num);
2241 bio->bi_status = ret;
2248 * given a list of ordered sums record them in the inode. This happens
2249 * at IO completion time based on sums calculated at bio submission time.
2251 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
2252 struct inode *inode, struct list_head *list)
2254 struct btrfs_ordered_sum *sum;
2257 list_for_each_entry(sum, list, list) {
2258 trans->adding_csums = true;
2259 ret = btrfs_csum_file_blocks(trans,
2260 BTRFS_I(inode)->root->fs_info->csum_root, sum);
2261 trans->adding_csums = false;
2268 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
2269 unsigned int extra_bits,
2270 struct extent_state **cached_state)
2272 WARN_ON(PAGE_ALIGNED(end));
2273 return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
2274 extra_bits, cached_state);
2277 /* see btrfs_writepage_start_hook for details on why this is required */
2278 struct btrfs_writepage_fixup {
2280 struct inode *inode;
2281 struct btrfs_work work;
2284 static void btrfs_writepage_fixup_worker(struct btrfs_work *work)
2286 struct btrfs_writepage_fixup *fixup;
2287 struct btrfs_ordered_extent *ordered;
2288 struct extent_state *cached_state = NULL;
2289 struct extent_changeset *data_reserved = NULL;
2291 struct inode *inode;
2295 bool free_delalloc_space = true;
2297 fixup = container_of(work, struct btrfs_writepage_fixup, work);
2299 inode = fixup->inode;
2300 page_start = page_offset(page);
2301 page_end = page_offset(page) + PAGE_SIZE - 1;
2304 * This is similar to page_mkwrite, we need to reserve the space before
2305 * we take the page lock.
2307 ret = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start,
2313 * Before we queued this fixup, we took a reference on the page.
2314 * page->mapping may go NULL, but it shouldn't be moved to a different
2317 if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
2319 * Unfortunately this is a little tricky, either
2321 * 1) We got here and our page had already been dealt with and
2322 * we reserved our space, thus ret == 0, so we need to just
2323 * drop our space reservation and bail. This can happen the
2324 * first time we come into the fixup worker, or could happen
2325 * while waiting for the ordered extent.
2326 * 2) Our page was already dealt with, but we happened to get an
2327 * ENOSPC above from the btrfs_delalloc_reserve_space. In
2328 * this case we obviously don't have anything to release, but
2329 * because the page was already dealt with we don't want to
2330 * mark the page with an error, so make sure we're resetting
2331 * ret to 0. This is why we have this check _before_ the ret
2332 * check, because we do not want to have a surprise ENOSPC
2333 * when the page was already properly dealt with.
2336 btrfs_delalloc_release_extents(BTRFS_I(inode),
2338 btrfs_delalloc_release_space(inode, data_reserved,
2339 page_start, PAGE_SIZE,
2347 * We can't mess with the page state unless it is locked, so now that
2348 * it is locked bail if we failed to make our space reservation.
2353 lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end,
2356 /* already ordered? We're done */
2357 if (PagePrivate2(page))
2360 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), page_start,
2363 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start,
2364 page_end, &cached_state);
2366 btrfs_start_ordered_extent(inode, ordered, 1);
2367 btrfs_put_ordered_extent(ordered);
2371 ret = btrfs_set_extent_delalloc(inode, page_start, page_end, 0,
2377 * Everything went as planned, we're now the owner of a dirty page with
2378 * delayed allocation bits set and space reserved for our COW
2381 * The page was dirty when we started, nothing should have cleaned it.
2383 BUG_ON(!PageDirty(page));
2384 free_delalloc_space = false;
2386 btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE);
2387 if (free_delalloc_space)
2388 btrfs_delalloc_release_space(inode, data_reserved, page_start,
2390 unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end,
2395 * We hit ENOSPC or other errors. Update the mapping and page
2396 * to reflect the errors and clean the page.
2398 mapping_set_error(page->mapping, ret);
2399 end_extent_writepage(page, ret, page_start, page_end);
2400 clear_page_dirty_for_io(page);
2403 ClearPageChecked(page);
2407 extent_changeset_free(data_reserved);
2409 * As a precaution, do a delayed iput in case it would be the last iput
2410 * that could need flushing space. Recursing back to fixup worker would
2413 btrfs_add_delayed_iput(inode);
2417 * There are a few paths in the higher layers of the kernel that directly
2418 * set the page dirty bit without asking the filesystem if it is a
2419 * good idea. This causes problems because we want to make sure COW
2420 * properly happens and the data=ordered rules are followed.
2422 * In our case any range that doesn't have the ORDERED bit set
2423 * hasn't been properly setup for IO. We kick off an async process
2424 * to fix it up. The async helper will wait for ordered extents, set
2425 * the delalloc bit and make it safe to write the page.
2427 int btrfs_writepage_cow_fixup(struct page *page, u64 start, u64 end)
2429 struct inode *inode = page->mapping->host;
2430 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2431 struct btrfs_writepage_fixup *fixup;
2433 /* this page is properly in the ordered list */
2434 if (TestClearPagePrivate2(page))
2438 * PageChecked is set below when we create a fixup worker for this page,
2439 * don't try to create another one if we're already PageChecked()
2441 * The extent_io writepage code will redirty the page if we send back
2444 if (PageChecked(page))
2447 fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
2452 * We are already holding a reference to this inode from
2453 * write_cache_pages. We need to hold it because the space reservation
2454 * takes place outside of the page lock, and we can't trust
2455 * page->mapping outside of the page lock.
2458 SetPageChecked(page);
2460 btrfs_init_work(&fixup->work, btrfs_writepage_fixup_worker, NULL, NULL);
2462 fixup->inode = inode;
2463 btrfs_queue_work(fs_info->fixup_workers, &fixup->work);
2468 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
2469 struct inode *inode, u64 file_pos,
2470 u64 disk_bytenr, u64 disk_num_bytes,
2471 u64 num_bytes, u64 ram_bytes,
2472 u8 compression, u8 encryption,
2473 u16 other_encoding, int extent_type)
2475 struct btrfs_root *root = BTRFS_I(inode)->root;
2476 struct btrfs_file_extent_item *fi;
2477 struct btrfs_path *path;
2478 struct extent_buffer *leaf;
2479 struct btrfs_key ins;
2481 int extent_inserted = 0;
2484 path = btrfs_alloc_path();
2489 * we may be replacing one extent in the tree with another.
2490 * The new extent is pinned in the extent map, and we don't want
2491 * to drop it from the cache until it is completely in the btree.
2493 * So, tell btrfs_drop_extents to leave this extent in the cache.
2494 * the caller is expected to unpin it and allow it to be merged
2497 ret = __btrfs_drop_extents(trans, root, inode, path, file_pos,
2498 file_pos + num_bytes, NULL, 0,
2499 1, sizeof(*fi), &extent_inserted);
2503 if (!extent_inserted) {
2504 ins.objectid = btrfs_ino(BTRFS_I(inode));
2505 ins.offset = file_pos;
2506 ins.type = BTRFS_EXTENT_DATA_KEY;
2508 path->leave_spinning = 1;
2509 ret = btrfs_insert_empty_item(trans, root, path, &ins,
2514 leaf = path->nodes[0];
2515 fi = btrfs_item_ptr(leaf, path->slots[0],
2516 struct btrfs_file_extent_item);
2517 btrfs_set_file_extent_generation(leaf, fi, trans->transid);
2518 btrfs_set_file_extent_type(leaf, fi, extent_type);
2519 btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr);
2520 btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes);
2521 btrfs_set_file_extent_offset(leaf, fi, 0);
2522 btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes);
2523 btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes);
2524 btrfs_set_file_extent_compression(leaf, fi, compression);
2525 btrfs_set_file_extent_encryption(leaf, fi, encryption);
2526 btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding);
2528 btrfs_mark_buffer_dirty(leaf);
2529 btrfs_release_path(path);
2531 inode_add_bytes(inode, num_bytes);
2533 ins.objectid = disk_bytenr;
2534 ins.offset = disk_num_bytes;
2535 ins.type = BTRFS_EXTENT_ITEM_KEY;
2537 ret = btrfs_inode_set_file_extent_range(BTRFS_I(inode), file_pos,
2543 * Release the reserved range from inode dirty range map, as it is
2544 * already moved into delayed_ref_head
2546 ret = btrfs_qgroup_release_data(inode, file_pos, ram_bytes);
2550 ret = btrfs_alloc_reserved_file_extent(trans, root,
2551 btrfs_ino(BTRFS_I(inode)),
2552 file_pos, qg_released, &ins);
2554 btrfs_free_path(path);
2559 static void btrfs_release_delalloc_bytes(struct btrfs_fs_info *fs_info,
2562 struct btrfs_block_group *cache;
2564 cache = btrfs_lookup_block_group(fs_info, start);
2567 spin_lock(&cache->lock);
2568 cache->delalloc_bytes -= len;
2569 spin_unlock(&cache->lock);
2571 btrfs_put_block_group(cache);
2574 /* as ordered data IO finishes, this gets called so we can finish
2575 * an ordered extent if the range of bytes in the file it covers are
2578 static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
2580 struct inode *inode = ordered_extent->inode;
2581 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2582 struct btrfs_root *root = BTRFS_I(inode)->root;
2583 struct btrfs_trans_handle *trans = NULL;
2584 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2585 struct extent_state *cached_state = NULL;
2587 int compress_type = 0;
2589 u64 logical_len = ordered_extent->num_bytes;
2590 bool freespace_inode;
2591 bool truncated = false;
2592 bool range_locked = false;
2593 bool clear_new_delalloc_bytes = false;
2594 bool clear_reserved_extent = true;
2595 unsigned int clear_bits;
2597 start = ordered_extent->file_offset;
2598 end = start + ordered_extent->num_bytes - 1;
2600 if (!test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) &&
2601 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags) &&
2602 !test_bit(BTRFS_ORDERED_DIRECT, &ordered_extent->flags))
2603 clear_new_delalloc_bytes = true;
2605 freespace_inode = btrfs_is_free_space_inode(BTRFS_I(inode));
2607 if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) {
2612 btrfs_free_io_failure_record(BTRFS_I(inode), start, end);
2614 if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) {
2616 logical_len = ordered_extent->truncated_len;
2617 /* Truncated the entire extent, don't bother adding */
2622 if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) {
2623 BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */
2626 * For mwrite(mmap + memset to write) case, we still reserve
2627 * space for NOCOW range.
2628 * As NOCOW won't cause a new delayed ref, just free the space
2630 btrfs_qgroup_free_data(inode, NULL, start,
2631 ordered_extent->num_bytes);
2632 btrfs_inode_safe_disk_i_size_write(inode, 0);
2633 if (freespace_inode)
2634 trans = btrfs_join_transaction_spacecache(root);
2636 trans = btrfs_join_transaction(root);
2637 if (IS_ERR(trans)) {
2638 ret = PTR_ERR(trans);
2642 trans->block_rsv = &BTRFS_I(inode)->block_rsv;
2643 ret = btrfs_update_inode_fallback(trans, root, inode);
2644 if (ret) /* -ENOMEM or corruption */
2645 btrfs_abort_transaction(trans, ret);
2649 range_locked = true;
2650 lock_extent_bits(io_tree, start, end, &cached_state);
2652 if (freespace_inode)
2653 trans = btrfs_join_transaction_spacecache(root);
2655 trans = btrfs_join_transaction(root);
2656 if (IS_ERR(trans)) {
2657 ret = PTR_ERR(trans);
2662 trans->block_rsv = &BTRFS_I(inode)->block_rsv;
2664 if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
2665 compress_type = ordered_extent->compress_type;
2666 if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
2667 BUG_ON(compress_type);
2668 btrfs_qgroup_free_data(inode, NULL, start,
2669 ordered_extent->num_bytes);
2670 ret = btrfs_mark_extent_written(trans, BTRFS_I(inode),
2671 ordered_extent->file_offset,
2672 ordered_extent->file_offset +
2675 BUG_ON(root == fs_info->tree_root);
2676 ret = insert_reserved_file_extent(trans, inode, start,
2677 ordered_extent->disk_bytenr,
2678 ordered_extent->disk_num_bytes,
2679 logical_len, logical_len,
2680 compress_type, 0, 0,
2681 BTRFS_FILE_EXTENT_REG);
2683 clear_reserved_extent = false;
2684 btrfs_release_delalloc_bytes(fs_info,
2685 ordered_extent->disk_bytenr,
2686 ordered_extent->disk_num_bytes);
2689 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
2690 ordered_extent->file_offset,
2691 ordered_extent->num_bytes, trans->transid);
2693 btrfs_abort_transaction(trans, ret);
2697 ret = add_pending_csums(trans, inode, &ordered_extent->list);
2699 btrfs_abort_transaction(trans, ret);
2703 btrfs_inode_safe_disk_i_size_write(inode, 0);
2704 ret = btrfs_update_inode_fallback(trans, root, inode);
2705 if (ret) { /* -ENOMEM or corruption */
2706 btrfs_abort_transaction(trans, ret);
2711 clear_bits = EXTENT_DEFRAG;
2713 clear_bits |= EXTENT_LOCKED;
2714 if (clear_new_delalloc_bytes)
2715 clear_bits |= EXTENT_DELALLOC_NEW;
2716 clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, clear_bits,
2717 (clear_bits & EXTENT_LOCKED) ? 1 : 0, 0,
2721 btrfs_end_transaction(trans);
2723 if (ret || truncated) {
2724 u64 unwritten_start = start;
2727 unwritten_start += logical_len;
2728 clear_extent_uptodate(io_tree, unwritten_start, end, NULL);
2730 /* Drop the cache for the part of the extent we didn't write. */
2731 btrfs_drop_extent_cache(BTRFS_I(inode), unwritten_start, end, 0);
2734 * If the ordered extent had an IOERR or something else went
2735 * wrong we need to return the space for this ordered extent
2736 * back to the allocator. We only free the extent in the
2737 * truncated case if we didn't write out the extent at all.
2739 * If we made it past insert_reserved_file_extent before we
2740 * errored out then we don't need to do this as the accounting
2741 * has already been done.
2743 if ((ret || !logical_len) &&
2744 clear_reserved_extent &&
2745 !test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) &&
2746 !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
2748 * Discard the range before returning it back to the
2751 if (ret && btrfs_test_opt(fs_info, DISCARD_SYNC))
2752 btrfs_discard_extent(fs_info,
2753 ordered_extent->disk_bytenr,
2754 ordered_extent->disk_num_bytes,
2756 btrfs_free_reserved_extent(fs_info,
2757 ordered_extent->disk_bytenr,
2758 ordered_extent->disk_num_bytes, 1);
2763 * This needs to be done to make sure anybody waiting knows we are done
2764 * updating everything for this ordered extent.
2766 btrfs_remove_ordered_extent(inode, ordered_extent);
2769 btrfs_put_ordered_extent(ordered_extent);
2770 /* once for the tree */
2771 btrfs_put_ordered_extent(ordered_extent);
2776 static void finish_ordered_fn(struct btrfs_work *work)
2778 struct btrfs_ordered_extent *ordered_extent;
2779 ordered_extent = container_of(work, struct btrfs_ordered_extent, work);
2780 btrfs_finish_ordered_io(ordered_extent);
2783 void btrfs_writepage_endio_finish_ordered(struct page *page, u64 start,
2784 u64 end, int uptodate)
2786 struct inode *inode = page->mapping->host;
2787 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2788 struct btrfs_ordered_extent *ordered_extent = NULL;
2789 struct btrfs_workqueue *wq;
2791 trace_btrfs_writepage_end_io_hook(page, start, end, uptodate);
2793 ClearPagePrivate2(page);
2794 if (!btrfs_dec_test_ordered_pending(inode, &ordered_extent, start,
2795 end - start + 1, uptodate))
2798 if (btrfs_is_free_space_inode(BTRFS_I(inode)))
2799 wq = fs_info->endio_freespace_worker;
2801 wq = fs_info->endio_write_workers;
2803 btrfs_init_work(&ordered_extent->work, finish_ordered_fn, NULL, NULL);
2804 btrfs_queue_work(wq, &ordered_extent->work);
2807 static int check_data_csum(struct inode *inode, struct btrfs_io_bio *io_bio,
2808 int icsum, struct page *page, int pgoff, u64 start,
2811 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2812 SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
2814 u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
2816 u8 csum[BTRFS_CSUM_SIZE];
2818 csum_expected = ((u8 *)io_bio->csum) + icsum * csum_size;
2820 kaddr = kmap_atomic(page);
2821 shash->tfm = fs_info->csum_shash;
2823 crypto_shash_digest(shash, kaddr + pgoff, len, csum);
2825 if (memcmp(csum, csum_expected, csum_size))
2828 kunmap_atomic(kaddr);
2831 btrfs_print_data_csum_error(BTRFS_I(inode), start, csum, csum_expected,
2832 io_bio->mirror_num);
2833 memset(kaddr + pgoff, 1, len);
2834 flush_dcache_page(page);
2835 kunmap_atomic(kaddr);
2840 * when reads are done, we need to check csums to verify the data is correct
2841 * if there's a match, we allow the bio to finish. If not, the code in
2842 * extent_io.c will try to find good copies for us.
2844 static int btrfs_readpage_end_io_hook(struct btrfs_io_bio *io_bio,
2845 u64 phy_offset, struct page *page,
2846 u64 start, u64 end, int mirror)
2848 size_t offset = start - page_offset(page);
2849 struct inode *inode = page->mapping->host;
2850 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2851 struct btrfs_root *root = BTRFS_I(inode)->root;
2853 if (PageChecked(page)) {
2854 ClearPageChecked(page);
2858 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
2861 if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
2862 test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
2863 clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM);
2867 phy_offset >>= inode->i_sb->s_blocksize_bits;
2868 return check_data_csum(inode, io_bio, phy_offset, page, offset, start,
2869 (size_t)(end - start + 1));
2873 * btrfs_add_delayed_iput - perform a delayed iput on @inode
2875 * @inode: The inode we want to perform iput on
2877 * This function uses the generic vfs_inode::i_count to track whether we should
2878 * just decrement it (in case it's > 1) or if this is the last iput then link
2879 * the inode to the delayed iput machinery. Delayed iputs are processed at
2880 * transaction commit time/superblock commit/cleaner kthread.
2882 void btrfs_add_delayed_iput(struct inode *inode)
2884 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2885 struct btrfs_inode *binode = BTRFS_I(inode);
2887 if (atomic_add_unless(&inode->i_count, -1, 1))
2890 atomic_inc(&fs_info->nr_delayed_iputs);
2891 spin_lock(&fs_info->delayed_iput_lock);
2892 ASSERT(list_empty(&binode->delayed_iput));
2893 list_add_tail(&binode->delayed_iput, &fs_info->delayed_iputs);
2894 spin_unlock(&fs_info->delayed_iput_lock);
2895 if (!test_bit(BTRFS_FS_CLEANER_RUNNING, &fs_info->flags))
2896 wake_up_process(fs_info->cleaner_kthread);
2899 static void run_delayed_iput_locked(struct btrfs_fs_info *fs_info,
2900 struct btrfs_inode *inode)
2902 list_del_init(&inode->delayed_iput);
2903 spin_unlock(&fs_info->delayed_iput_lock);
2904 iput(&inode->vfs_inode);
2905 if (atomic_dec_and_test(&fs_info->nr_delayed_iputs))
2906 wake_up(&fs_info->delayed_iputs_wait);
2907 spin_lock(&fs_info->delayed_iput_lock);
2910 static void btrfs_run_delayed_iput(struct btrfs_fs_info *fs_info,
2911 struct btrfs_inode *inode)
2913 if (!list_empty(&inode->delayed_iput)) {
2914 spin_lock(&fs_info->delayed_iput_lock);
2915 if (!list_empty(&inode->delayed_iput))
2916 run_delayed_iput_locked(fs_info, inode);
2917 spin_unlock(&fs_info->delayed_iput_lock);
2921 void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info)
2924 spin_lock(&fs_info->delayed_iput_lock);
2925 while (!list_empty(&fs_info->delayed_iputs)) {
2926 struct btrfs_inode *inode;
2928 inode = list_first_entry(&fs_info->delayed_iputs,
2929 struct btrfs_inode, delayed_iput);
2930 run_delayed_iput_locked(fs_info, inode);
2932 spin_unlock(&fs_info->delayed_iput_lock);
2936 * btrfs_wait_on_delayed_iputs - wait on the delayed iputs to be done running
2937 * @fs_info - the fs_info for this fs
2938 * @return - EINTR if we were killed, 0 if nothing's pending
2940 * This will wait on any delayed iputs that are currently running with KILLABLE
2941 * set. Once they are all done running we will return, unless we are killed in
2942 * which case we return EINTR. This helps in user operations like fallocate etc
2943 * that might get blocked on the iputs.
2945 int btrfs_wait_on_delayed_iputs(struct btrfs_fs_info *fs_info)
2947 int ret = wait_event_killable(fs_info->delayed_iputs_wait,
2948 atomic_read(&fs_info->nr_delayed_iputs) == 0);
2955 * This creates an orphan entry for the given inode in case something goes wrong
2956 * in the middle of an unlink.
2958 int btrfs_orphan_add(struct btrfs_trans_handle *trans,
2959 struct btrfs_inode *inode)
2963 ret = btrfs_insert_orphan_item(trans, inode->root, btrfs_ino(inode));
2964 if (ret && ret != -EEXIST) {
2965 btrfs_abort_transaction(trans, ret);
2973 * We have done the delete so we can go ahead and remove the orphan item for
2974 * this particular inode.
2976 static int btrfs_orphan_del(struct btrfs_trans_handle *trans,
2977 struct btrfs_inode *inode)
2979 return btrfs_del_orphan_item(trans, inode->root, btrfs_ino(inode));
2983 * this cleans up any orphans that may be left on the list from the last use
2986 int btrfs_orphan_cleanup(struct btrfs_root *root)
2988 struct btrfs_fs_info *fs_info = root->fs_info;
2989 struct btrfs_path *path;
2990 struct extent_buffer *leaf;
2991 struct btrfs_key key, found_key;
2992 struct btrfs_trans_handle *trans;
2993 struct inode *inode;
2994 u64 last_objectid = 0;
2995 int ret = 0, nr_unlink = 0;
2997 if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
3000 path = btrfs_alloc_path();
3005 path->reada = READA_BACK;
3007 key.objectid = BTRFS_ORPHAN_OBJECTID;
3008 key.type = BTRFS_ORPHAN_ITEM_KEY;
3009 key.offset = (u64)-1;
3012 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3017 * if ret == 0 means we found what we were searching for, which
3018 * is weird, but possible, so only screw with path if we didn't
3019 * find the key and see if we have stuff that matches
3023 if (path->slots[0] == 0)
3028 /* pull out the item */
3029 leaf = path->nodes[0];
3030 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
3032 /* make sure the item matches what we want */
3033 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
3035 if (found_key.type != BTRFS_ORPHAN_ITEM_KEY)
3038 /* release the path since we're done with it */
3039 btrfs_release_path(path);
3042 * this is where we are basically btrfs_lookup, without the
3043 * crossing root thing. we store the inode number in the
3044 * offset of the orphan item.
3047 if (found_key.offset == last_objectid) {
3049 "Error removing orphan entry, stopping orphan cleanup");
3054 last_objectid = found_key.offset;
3056 found_key.objectid = found_key.offset;
3057 found_key.type = BTRFS_INODE_ITEM_KEY;
3058 found_key.offset = 0;
3059 inode = btrfs_iget(fs_info->sb, last_objectid, root);
3060 ret = PTR_ERR_OR_ZERO(inode);
3061 if (ret && ret != -ENOENT)
3064 if (ret == -ENOENT && root == fs_info->tree_root) {
3065 struct btrfs_root *dead_root;
3066 struct btrfs_fs_info *fs_info = root->fs_info;
3067 int is_dead_root = 0;
3070 * this is an orphan in the tree root. Currently these
3071 * could come from 2 sources:
3072 * a) a snapshot deletion in progress
3073 * b) a free space cache inode
3074 * We need to distinguish those two, as the snapshot
3075 * orphan must not get deleted.
3076 * find_dead_roots already ran before us, so if this
3077 * is a snapshot deletion, we should find the root
3078 * in the fs_roots radix tree.
3081 spin_lock(&fs_info->fs_roots_radix_lock);
3082 dead_root = radix_tree_lookup(&fs_info->fs_roots_radix,
3083 (unsigned long)found_key.objectid);
3084 if (dead_root && btrfs_root_refs(&dead_root->root_item) == 0)
3086 spin_unlock(&fs_info->fs_roots_radix_lock);
3089 /* prevent this orphan from being found again */
3090 key.offset = found_key.objectid - 1;
3097 * If we have an inode with links, there are a couple of
3098 * possibilities. Old kernels (before v3.12) used to create an
3099 * orphan item for truncate indicating that there were possibly
3100 * extent items past i_size that needed to be deleted. In v3.12,
3101 * truncate was changed to update i_size in sync with the extent
3102 * items, but the (useless) orphan item was still created. Since
3103 * v4.18, we don't create the orphan item for truncate at all.
3105 * So, this item could mean that we need to do a truncate, but
3106 * only if this filesystem was last used on a pre-v3.12 kernel
3107 * and was not cleanly unmounted. The odds of that are quite
3108 * slim, and it's a pain to do the truncate now, so just delete
3111 * It's also possible that this orphan item was supposed to be
3112 * deleted but wasn't. The inode number may have been reused,
3113 * but either way, we can delete the orphan item.
3115 if (ret == -ENOENT || inode->i_nlink) {
3118 trans = btrfs_start_transaction(root, 1);
3119 if (IS_ERR(trans)) {
3120 ret = PTR_ERR(trans);
3123 btrfs_debug(fs_info, "auto deleting %Lu",
3124 found_key.objectid);
3125 ret = btrfs_del_orphan_item(trans, root,
3126 found_key.objectid);
3127 btrfs_end_transaction(trans);
3135 /* this will do delete_inode and everything for us */
3138 /* release the path since we're done with it */
3139 btrfs_release_path(path);
3141 root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
3143 if (test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state)) {
3144 trans = btrfs_join_transaction(root);
3146 btrfs_end_transaction(trans);
3150 btrfs_debug(fs_info, "unlinked %d orphans", nr_unlink);
3154 btrfs_err(fs_info, "could not do orphan cleanup %d", ret);
3155 btrfs_free_path(path);
3160 * very simple check to peek ahead in the leaf looking for xattrs. If we
3161 * don't find any xattrs, we know there can't be any acls.
3163 * slot is the slot the inode is in, objectid is the objectid of the inode
3165 static noinline int acls_after_inode_item(struct extent_buffer *leaf,
3166 int slot, u64 objectid,
3167 int *first_xattr_slot)
3169 u32 nritems = btrfs_header_nritems(leaf);
3170 struct btrfs_key found_key;
3171 static u64 xattr_access = 0;
3172 static u64 xattr_default = 0;
3175 if (!xattr_access) {
3176 xattr_access = btrfs_name_hash(XATTR_NAME_POSIX_ACL_ACCESS,
3177 strlen(XATTR_NAME_POSIX_ACL_ACCESS));
3178 xattr_default = btrfs_name_hash(XATTR_NAME_POSIX_ACL_DEFAULT,
3179 strlen(XATTR_NAME_POSIX_ACL_DEFAULT));
3183 *first_xattr_slot = -1;
3184 while (slot < nritems) {
3185 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3187 /* we found a different objectid, there must not be acls */
3188 if (found_key.objectid != objectid)
3191 /* we found an xattr, assume we've got an acl */
3192 if (found_key.type == BTRFS_XATTR_ITEM_KEY) {
3193 if (*first_xattr_slot == -1)
3194 *first_xattr_slot = slot;
3195 if (found_key.offset == xattr_access ||
3196 found_key.offset == xattr_default)
3201 * we found a key greater than an xattr key, there can't
3202 * be any acls later on
3204 if (found_key.type > BTRFS_XATTR_ITEM_KEY)
3211 * it goes inode, inode backrefs, xattrs, extents,
3212 * so if there are a ton of hard links to an inode there can
3213 * be a lot of backrefs. Don't waste time searching too hard,
3214 * this is just an optimization
3219 /* we hit the end of the leaf before we found an xattr or
3220 * something larger than an xattr. We have to assume the inode
3223 if (*first_xattr_slot == -1)
3224 *first_xattr_slot = slot;
3229 * read an inode from the btree into the in-memory inode
3231 static int btrfs_read_locked_inode(struct inode *inode,
3232 struct btrfs_path *in_path)
3234 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3235 struct btrfs_path *path = in_path;
3236 struct extent_buffer *leaf;
3237 struct btrfs_inode_item *inode_item;
3238 struct btrfs_root *root = BTRFS_I(inode)->root;
3239 struct btrfs_key location;
3244 bool filled = false;
3245 int first_xattr_slot;
3247 ret = btrfs_fill_inode(inode, &rdev);
3252 path = btrfs_alloc_path();
3257 memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
3259 ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
3261 if (path != in_path)
3262 btrfs_free_path(path);
3266 leaf = path->nodes[0];
3271 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3272 struct btrfs_inode_item);
3273 inode->i_mode = btrfs_inode_mode(leaf, inode_item);
3274 set_nlink(inode, btrfs_inode_nlink(leaf, inode_item));
3275 i_uid_write(inode, btrfs_inode_uid(leaf, inode_item));
3276 i_gid_write(inode, btrfs_inode_gid(leaf, inode_item));
3277 btrfs_i_size_write(BTRFS_I(inode), btrfs_inode_size(leaf, inode_item));
3278 btrfs_inode_set_file_extent_range(BTRFS_I(inode), 0,
3279 round_up(i_size_read(inode), fs_info->sectorsize));
3281 inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->atime);
3282 inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->atime);
3284 inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->mtime);
3285 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->mtime);
3287 inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, &inode_item->ctime);
3288 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, &inode_item->ctime);
3290 BTRFS_I(inode)->i_otime.tv_sec =
3291 btrfs_timespec_sec(leaf, &inode_item->otime);
3292 BTRFS_I(inode)->i_otime.tv_nsec =
3293 btrfs_timespec_nsec(leaf, &inode_item->otime);
3295 inode_set_bytes(inode, btrfs_inode_nbytes(leaf, inode_item));
3296 BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
3297 BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item);
3299 inode_set_iversion_queried(inode,
3300 btrfs_inode_sequence(leaf, inode_item));
3301 inode->i_generation = BTRFS_I(inode)->generation;
3303 rdev = btrfs_inode_rdev(leaf, inode_item);
3305 BTRFS_I(inode)->index_cnt = (u64)-1;
3306 BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
3310 * If we were modified in the current generation and evicted from memory
3311 * and then re-read we need to do a full sync since we don't have any
3312 * idea about which extents were modified before we were evicted from
3315 * This is required for both inode re-read from disk and delayed inode
3316 * in delayed_nodes_tree.
3318 if (BTRFS_I(inode)->last_trans == fs_info->generation)
3319 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3320 &BTRFS_I(inode)->runtime_flags);
3323 * We don't persist the id of the transaction where an unlink operation
3324 * against the inode was last made. So here we assume the inode might
3325 * have been evicted, and therefore the exact value of last_unlink_trans
3326 * lost, and set it to last_trans to avoid metadata inconsistencies
3327 * between the inode and its parent if the inode is fsync'ed and the log
3328 * replayed. For example, in the scenario:
3331 * ln mydir/foo mydir/bar
3334 * echo 2 > /proc/sys/vm/drop_caches # evicts inode
3335 * xfs_io -c fsync mydir/foo
3337 * mount fs, triggers fsync log replay
3339 * We must make sure that when we fsync our inode foo we also log its
3340 * parent inode, otherwise after log replay the parent still has the
3341 * dentry with the "bar" name but our inode foo has a link count of 1
3342 * and doesn't have an inode ref with the name "bar" anymore.
3344 * Setting last_unlink_trans to last_trans is a pessimistic approach,
3345 * but it guarantees correctness at the expense of occasional full
3346 * transaction commits on fsync if our inode is a directory, or if our
3347 * inode is not a directory, logging its parent unnecessarily.
3349 BTRFS_I(inode)->last_unlink_trans = BTRFS_I(inode)->last_trans;
3352 if (inode->i_nlink != 1 ||
3353 path->slots[0] >= btrfs_header_nritems(leaf))
3356 btrfs_item_key_to_cpu(leaf, &location, path->slots[0]);
3357 if (location.objectid != btrfs_ino(BTRFS_I(inode)))
3360 ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
3361 if (location.type == BTRFS_INODE_REF_KEY) {
3362 struct btrfs_inode_ref *ref;
3364 ref = (struct btrfs_inode_ref *)ptr;
3365 BTRFS_I(inode)->dir_index = btrfs_inode_ref_index(leaf, ref);
3366 } else if (location.type == BTRFS_INODE_EXTREF_KEY) {
3367 struct btrfs_inode_extref *extref;
3369 extref = (struct btrfs_inode_extref *)ptr;
3370 BTRFS_I(inode)->dir_index = btrfs_inode_extref_index(leaf,
3375 * try to precache a NULL acl entry for files that don't have
3376 * any xattrs or acls
3378 maybe_acls = acls_after_inode_item(leaf, path->slots[0],
3379 btrfs_ino(BTRFS_I(inode)), &first_xattr_slot);
3380 if (first_xattr_slot != -1) {
3381 path->slots[0] = first_xattr_slot;
3382 ret = btrfs_load_inode_props(inode, path);
3385 "error loading props for ino %llu (root %llu): %d",
3386 btrfs_ino(BTRFS_I(inode)),
3387 root->root_key.objectid, ret);
3389 if (path != in_path)
3390 btrfs_free_path(path);
3393 cache_no_acl(inode);
3395 switch (inode->i_mode & S_IFMT) {
3397 inode->i_mapping->a_ops = &btrfs_aops;
3398 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
3399 inode->i_fop = &btrfs_file_operations;
3400 inode->i_op = &btrfs_file_inode_operations;
3403 inode->i_fop = &btrfs_dir_file_operations;
3404 inode->i_op = &btrfs_dir_inode_operations;
3407 inode->i_op = &btrfs_symlink_inode_operations;
3408 inode_nohighmem(inode);
3409 inode->i_mapping->a_ops = &btrfs_aops;
3412 inode->i_op = &btrfs_special_inode_operations;
3413 init_special_inode(inode, inode->i_mode, rdev);
3417 btrfs_sync_inode_flags_to_i_flags(inode);
3422 * given a leaf and an inode, copy the inode fields into the leaf
3424 static void fill_inode_item(struct btrfs_trans_handle *trans,
3425 struct extent_buffer *leaf,
3426 struct btrfs_inode_item *item,
3427 struct inode *inode)
3429 struct btrfs_map_token token;
3431 btrfs_init_map_token(&token, leaf);
3433 btrfs_set_token_inode_uid(&token, item, i_uid_read(inode));
3434 btrfs_set_token_inode_gid(&token, item, i_gid_read(inode));
3435 btrfs_set_token_inode_size(&token, item, BTRFS_I(inode)->disk_i_size);
3436 btrfs_set_token_inode_mode(&token, item, inode->i_mode);
3437 btrfs_set_token_inode_nlink(&token, item, inode->i_nlink);
3439 btrfs_set_token_timespec_sec(&token, &item->atime,
3440 inode->i_atime.tv_sec);
3441 btrfs_set_token_timespec_nsec(&token, &item->atime,
3442 inode->i_atime.tv_nsec);
3444 btrfs_set_token_timespec_sec(&token, &item->mtime,
3445 inode->i_mtime.tv_sec);
3446 btrfs_set_token_timespec_nsec(&token, &item->mtime,
3447 inode->i_mtime.tv_nsec);
3449 btrfs_set_token_timespec_sec(&token, &item->ctime,
3450 inode->i_ctime.tv_sec);
3451 btrfs_set_token_timespec_nsec(&token, &item->ctime,
3452 inode->i_ctime.tv_nsec);
3454 btrfs_set_token_timespec_sec(&token, &item->otime,
3455 BTRFS_I(inode)->i_otime.tv_sec);
3456 btrfs_set_token_timespec_nsec(&token, &item->otime,
3457 BTRFS_I(inode)->i_otime.tv_nsec);
3459 btrfs_set_token_inode_nbytes(&token, item, inode_get_bytes(inode));
3460 btrfs_set_token_inode_generation(&token, item,
3461 BTRFS_I(inode)->generation);
3462 btrfs_set_token_inode_sequence(&token, item, inode_peek_iversion(inode));
3463 btrfs_set_token_inode_transid(&token, item, trans->transid);
3464 btrfs_set_token_inode_rdev(&token, item, inode->i_rdev);
3465 btrfs_set_token_inode_flags(&token, item, BTRFS_I(inode)->flags);
3466 btrfs_set_token_inode_block_group(&token, item, 0);
3470 * copy everything in the in-memory inode into the btree.
3472 static noinline int btrfs_update_inode_item(struct btrfs_trans_handle *trans,
3473 struct btrfs_root *root, struct inode *inode)
3475 struct btrfs_inode_item *inode_item;
3476 struct btrfs_path *path;
3477 struct extent_buffer *leaf;
3480 path = btrfs_alloc_path();
3484 path->leave_spinning = 1;
3485 ret = btrfs_lookup_inode(trans, root, path, &BTRFS_I(inode)->location,
3493 leaf = path->nodes[0];
3494 inode_item = btrfs_item_ptr(leaf, path->slots[0],
3495 struct btrfs_inode_item);
3497 fill_inode_item(trans, leaf, inode_item, inode);
3498 btrfs_mark_buffer_dirty(leaf);
3499 btrfs_set_inode_last_trans(trans, inode);
3502 btrfs_free_path(path);
3507 * copy everything in the in-memory inode into the btree.
3509 noinline int btrfs_update_inode(struct btrfs_trans_handle *trans,
3510 struct btrfs_root *root, struct inode *inode)
3512 struct btrfs_fs_info *fs_info = root->fs_info;
3516 * If the inode is a free space inode, we can deadlock during commit
3517 * if we put it into the delayed code.
3519 * The data relocation inode should also be directly updated
3522 if (!btrfs_is_free_space_inode(BTRFS_I(inode))
3523 && root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID
3524 && !test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags)) {
3525 btrfs_update_root_times(trans, root);
3527 ret = btrfs_delayed_update_inode(trans, root, inode);
3529 btrfs_set_inode_last_trans(trans, inode);
3533 return btrfs_update_inode_item(trans, root, inode);
3536 noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
3537 struct btrfs_root *root,
3538 struct inode *inode)
3542 ret = btrfs_update_inode(trans, root, inode);
3544 return btrfs_update_inode_item(trans, root, inode);
3549 * unlink helper that gets used here in inode.c and in the tree logging
3550 * recovery code. It remove a link in a directory with a given name, and
3551 * also drops the back refs in the inode to the directory
3553 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3554 struct btrfs_root *root,
3555 struct btrfs_inode *dir,
3556 struct btrfs_inode *inode,
3557 const char *name, int name_len)
3559 struct btrfs_fs_info *fs_info = root->fs_info;
3560 struct btrfs_path *path;
3562 struct btrfs_dir_item *di;
3564 u64 ino = btrfs_ino(inode);
3565 u64 dir_ino = btrfs_ino(dir);
3567 path = btrfs_alloc_path();
3573 path->leave_spinning = 1;
3574 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3575 name, name_len, -1);
3576 if (IS_ERR_OR_NULL(di)) {
3577 ret = di ? PTR_ERR(di) : -ENOENT;
3580 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3583 btrfs_release_path(path);
3586 * If we don't have dir index, we have to get it by looking up
3587 * the inode ref, since we get the inode ref, remove it directly,
3588 * it is unnecessary to do delayed deletion.
3590 * But if we have dir index, needn't search inode ref to get it.
3591 * Since the inode ref is close to the inode item, it is better
3592 * that we delay to delete it, and just do this deletion when
3593 * we update the inode item.
3595 if (inode->dir_index) {
3596 ret = btrfs_delayed_delete_inode_ref(inode);
3598 index = inode->dir_index;
3603 ret = btrfs_del_inode_ref(trans, root, name, name_len, ino,
3607 "failed to delete reference to %.*s, inode %llu parent %llu",
3608 name_len, name, ino, dir_ino);
3609 btrfs_abort_transaction(trans, ret);
3613 ret = btrfs_delete_delayed_dir_index(trans, dir, index);
3615 btrfs_abort_transaction(trans, ret);
3619 ret = btrfs_del_inode_ref_in_log(trans, root, name, name_len, inode,
3621 if (ret != 0 && ret != -ENOENT) {
3622 btrfs_abort_transaction(trans, ret);
3626 ret = btrfs_del_dir_entries_in_log(trans, root, name, name_len, dir,
3631 btrfs_abort_transaction(trans, ret);
3634 * If we have a pending delayed iput we could end up with the final iput
3635 * being run in btrfs-cleaner context. If we have enough of these built
3636 * up we can end up burning a lot of time in btrfs-cleaner without any
3637 * way to throttle the unlinks. Since we're currently holding a ref on
3638 * the inode we can run the delayed iput here without any issues as the
3639 * final iput won't be done until after we drop the ref we're currently
3642 btrfs_run_delayed_iput(fs_info, inode);
3644 btrfs_free_path(path);
3648 btrfs_i_size_write(dir, dir->vfs_inode.i_size - name_len * 2);
3649 inode_inc_iversion(&inode->vfs_inode);
3650 inode_inc_iversion(&dir->vfs_inode);
3651 inode->vfs_inode.i_ctime = dir->vfs_inode.i_mtime =
3652 dir->vfs_inode.i_ctime = current_time(&inode->vfs_inode);
3653 ret = btrfs_update_inode(trans, root, &dir->vfs_inode);
3658 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3659 struct btrfs_root *root,
3660 struct btrfs_inode *dir, struct btrfs_inode *inode,
3661 const char *name, int name_len)
3664 ret = __btrfs_unlink_inode(trans, root, dir, inode, name, name_len);
3666 drop_nlink(&inode->vfs_inode);
3667 ret = btrfs_update_inode(trans, root, &inode->vfs_inode);
3673 * helper to start transaction for unlink and rmdir.
3675 * unlink and rmdir are special in btrfs, they do not always free space, so
3676 * if we cannot make our reservations the normal way try and see if there is
3677 * plenty of slack room in the global reserve to migrate, otherwise we cannot
3678 * allow the unlink to occur.
3680 static struct btrfs_trans_handle *__unlink_start_trans(struct inode *dir)
3682 struct btrfs_root *root = BTRFS_I(dir)->root;
3685 * 1 for the possible orphan item
3686 * 1 for the dir item
3687 * 1 for the dir index
3688 * 1 for the inode ref
3691 return btrfs_start_transaction_fallback_global_rsv(root, 5);
3694 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
3696 struct btrfs_root *root = BTRFS_I(dir)->root;
3697 struct btrfs_trans_handle *trans;
3698 struct inode *inode = d_inode(dentry);
3701 trans = __unlink_start_trans(dir);
3703 return PTR_ERR(trans);
3705 btrfs_record_unlink_dir(trans, BTRFS_I(dir), BTRFS_I(d_inode(dentry)),
3708 ret = btrfs_unlink_inode(trans, root, BTRFS_I(dir),
3709 BTRFS_I(d_inode(dentry)), dentry->d_name.name,
3710 dentry->d_name.len);
3714 if (inode->i_nlink == 0) {
3715 ret = btrfs_orphan_add(trans, BTRFS_I(inode));
3721 btrfs_end_transaction(trans);
3722 btrfs_btree_balance_dirty(root->fs_info);
3726 static int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
3727 struct inode *dir, struct dentry *dentry)
3729 struct btrfs_root *root = BTRFS_I(dir)->root;
3730 struct btrfs_inode *inode = BTRFS_I(d_inode(dentry));
3731 struct btrfs_path *path;
3732 struct extent_buffer *leaf;
3733 struct btrfs_dir_item *di;
3734 struct btrfs_key key;
3735 const char *name = dentry->d_name.name;
3736 int name_len = dentry->d_name.len;
3740 u64 dir_ino = btrfs_ino(BTRFS_I(dir));
3742 if (btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID) {
3743 objectid = inode->root->root_key.objectid;
3744 } else if (btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) {
3745 objectid = inode->location.objectid;
3751 path = btrfs_alloc_path();
3755 di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
3756 name, name_len, -1);
3757 if (IS_ERR_OR_NULL(di)) {
3758 ret = di ? PTR_ERR(di) : -ENOENT;
3762 leaf = path->nodes[0];
3763 btrfs_dir_item_key_to_cpu(leaf, di, &key);
3764 WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
3765 ret = btrfs_delete_one_dir_name(trans, root, path, di);
3767 btrfs_abort_transaction(trans, ret);
3770 btrfs_release_path(path);
3773 * This is a placeholder inode for a subvolume we didn't have a
3774 * reference to at the time of the snapshot creation. In the meantime
3775 * we could have renamed the real subvol link into our snapshot, so
3776 * depending on btrfs_del_root_ref to return -ENOENT here is incorret.
3777 * Instead simply lookup the dir_index_item for this entry so we can
3778 * remove it. Otherwise we know we have a ref to the root and we can
3779 * call btrfs_del_root_ref, and it _shouldn't_ fail.
3781 if (btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) {
3782 di = btrfs_search_dir_index_item(root, path, dir_ino,
3784 if (IS_ERR_OR_NULL(di)) {
3789 btrfs_abort_transaction(trans, ret);
3793 leaf = path->nodes[0];
3794 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
3796 btrfs_release_path(path);
3798 ret = btrfs_del_root_ref(trans, objectid,
3799 root->root_key.objectid, dir_ino,
3800 &index, name, name_len);
3802 btrfs_abort_transaction(trans, ret);
3807 ret = btrfs_delete_delayed_dir_index(trans, BTRFS_I(dir), index);
3809 btrfs_abort_transaction(trans, ret);
3813 btrfs_i_size_write(BTRFS_I(dir), dir->i_size - name_len * 2);
3814 inode_inc_iversion(dir);
3815 dir->i_mtime = dir->i_ctime = current_time(dir);
3816 ret = btrfs_update_inode_fallback(trans, root, dir);
3818 btrfs_abort_transaction(trans, ret);
3820 btrfs_free_path(path);
3825 * Helper to check if the subvolume references other subvolumes or if it's
3828 static noinline int may_destroy_subvol(struct btrfs_root *root)
3830 struct btrfs_fs_info *fs_info = root->fs_info;
3831 struct btrfs_path *path;
3832 struct btrfs_dir_item *di;
3833 struct btrfs_key key;
3837 path = btrfs_alloc_path();
3841 /* Make sure this root isn't set as the default subvol */
3842 dir_id = btrfs_super_root_dir(fs_info->super_copy);
3843 di = btrfs_lookup_dir_item(NULL, fs_info->tree_root, path,
3844 dir_id, "default", 7, 0);
3845 if (di && !IS_ERR(di)) {
3846 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
3847 if (key.objectid == root->root_key.objectid) {
3850 "deleting default subvolume %llu is not allowed",
3854 btrfs_release_path(path);
3857 key.objectid = root->root_key.objectid;
3858 key.type = BTRFS_ROOT_REF_KEY;
3859 key.offset = (u64)-1;
3861 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
3867 if (path->slots[0] > 0) {
3869 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
3870 if (key.objectid == root->root_key.objectid &&
3871 key.type == BTRFS_ROOT_REF_KEY)
3875 btrfs_free_path(path);
3879 /* Delete all dentries for inodes belonging to the root */
3880 static void btrfs_prune_dentries(struct btrfs_root *root)
3882 struct btrfs_fs_info *fs_info = root->fs_info;
3883 struct rb_node *node;
3884 struct rb_node *prev;
3885 struct btrfs_inode *entry;
3886 struct inode *inode;
3889 if (!test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
3890 WARN_ON(btrfs_root_refs(&root->root_item) != 0);
3892 spin_lock(&root->inode_lock);
3894 node = root->inode_tree.rb_node;
3898 entry = rb_entry(node, struct btrfs_inode, rb_node);
3900 if (objectid < btrfs_ino(entry))
3901 node = node->rb_left;
3902 else if (objectid > btrfs_ino(entry))
3903 node = node->rb_right;
3909 entry = rb_entry(prev, struct btrfs_inode, rb_node);
3910 if (objectid <= btrfs_ino(entry)) {
3914 prev = rb_next(prev);
3918 entry = rb_entry(node, struct btrfs_inode, rb_node);
3919 objectid = btrfs_ino(entry) + 1;
3920 inode = igrab(&entry->vfs_inode);
3922 spin_unlock(&root->inode_lock);
3923 if (atomic_read(&inode->i_count) > 1)
3924 d_prune_aliases(inode);
3926 * btrfs_drop_inode will have it removed from the inode
3927 * cache when its usage count hits zero.
3931 spin_lock(&root->inode_lock);
3935 if (cond_resched_lock(&root->inode_lock))
3938 node = rb_next(node);
3940 spin_unlock(&root->inode_lock);
3943 int btrfs_delete_subvolume(struct inode *dir, struct dentry *dentry)
3945 struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb);
3946 struct btrfs_root *root = BTRFS_I(dir)->root;
3947 struct inode *inode = d_inode(dentry);
3948 struct btrfs_root *dest = BTRFS_I(inode)->root;
3949 struct btrfs_trans_handle *trans;
3950 struct btrfs_block_rsv block_rsv;
3956 * Don't allow to delete a subvolume with send in progress. This is
3957 * inside the inode lock so the error handling that has to drop the bit
3958 * again is not run concurrently.
3960 spin_lock(&dest->root_item_lock);
3961 if (dest->send_in_progress) {
3962 spin_unlock(&dest->root_item_lock);
3964 "attempt to delete subvolume %llu during send",
3965 dest->root_key.objectid);
3968 root_flags = btrfs_root_flags(&dest->root_item);
3969 btrfs_set_root_flags(&dest->root_item,
3970 root_flags | BTRFS_ROOT_SUBVOL_DEAD);
3971 spin_unlock(&dest->root_item_lock);
3973 down_write(&fs_info->subvol_sem);
3975 err = may_destroy_subvol(dest);
3979 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
3981 * One for dir inode,
3982 * two for dir entries,
3983 * two for root ref/backref.
3985 err = btrfs_subvolume_reserve_metadata(root, &block_rsv, 5, true);
3989 trans = btrfs_start_transaction(root, 0);
3990 if (IS_ERR(trans)) {
3991 err = PTR_ERR(trans);
3994 trans->block_rsv = &block_rsv;
3995 trans->bytes_reserved = block_rsv.size;
3997 btrfs_record_snapshot_destroy(trans, BTRFS_I(dir));
3999 ret = btrfs_unlink_subvol(trans, dir, dentry);
4002 btrfs_abort_transaction(trans, ret);
4006 btrfs_record_root_in_trans(trans, dest);
4008 memset(&dest->root_item.drop_progress, 0,
4009 sizeof(dest->root_item.drop_progress));
4010 dest->root_item.drop_level = 0;
4011 btrfs_set_root_refs(&dest->root_item, 0);
4013 if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
4014 ret = btrfs_insert_orphan_item(trans,
4016 dest->root_key.objectid);
4018 btrfs_abort_transaction(trans, ret);
4024 ret = btrfs_uuid_tree_remove(trans, dest->root_item.uuid,
4025 BTRFS_UUID_KEY_SUBVOL,
4026 dest->root_key.objectid);
4027 if (ret && ret != -ENOENT) {
4028 btrfs_abort_transaction(trans, ret);
4032 if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
4033 ret = btrfs_uuid_tree_remove(trans,
4034 dest->root_item.received_uuid,
4035 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4036 dest->root_key.objectid);
4037 if (ret && ret != -ENOENT) {
4038 btrfs_abort_transaction(trans, ret);
4045 trans->block_rsv = NULL;
4046 trans->bytes_reserved = 0;
4047 ret = btrfs_end_transaction(trans);
4050 inode->i_flags |= S_DEAD;
4052 btrfs_subvolume_release_metadata(fs_info, &block_rsv);
4054 up_write(&fs_info->subvol_sem);
4056 spin_lock(&dest->root_item_lock);
4057 root_flags = btrfs_root_flags(&dest->root_item);
4058 btrfs_set_root_flags(&dest->root_item,
4059 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
4060 spin_unlock(&dest->root_item_lock);
4062 d_invalidate(dentry);
4063 btrfs_prune_dentries(dest);
4064 ASSERT(dest->send_in_progress == 0);
4067 if (dest->ino_cache_inode) {
4068 iput(dest->ino_cache_inode);
4069 dest->ino_cache_inode = NULL;
4076 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
4078 struct inode *inode = d_inode(dentry);
4080 struct btrfs_root *root = BTRFS_I(dir)->root;
4081 struct btrfs_trans_handle *trans;
4082 u64 last_unlink_trans;
4084 if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
4086 if (btrfs_ino(BTRFS_I(inode)) == BTRFS_FIRST_FREE_OBJECTID)
4087 return btrfs_delete_subvolume(dir, dentry);
4089 trans = __unlink_start_trans(dir);
4091 return PTR_ERR(trans);
4093 if (unlikely(btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
4094 err = btrfs_unlink_subvol(trans, dir, dentry);
4098 err = btrfs_orphan_add(trans, BTRFS_I(inode));
4102 last_unlink_trans = BTRFS_I(inode)->last_unlink_trans;
4104 /* now the directory is empty */
4105 err = btrfs_unlink_inode(trans, root, BTRFS_I(dir),
4106 BTRFS_I(d_inode(dentry)), dentry->d_name.name,
4107 dentry->d_name.len);
4109 btrfs_i_size_write(BTRFS_I(inode), 0);
4111 * Propagate the last_unlink_trans value of the deleted dir to
4112 * its parent directory. This is to prevent an unrecoverable
4113 * log tree in the case we do something like this:
4115 * 2) create snapshot under dir foo
4116 * 3) delete the snapshot
4119 * 6) fsync foo or some file inside foo
4121 if (last_unlink_trans >= trans->transid)
4122 BTRFS_I(dir)->last_unlink_trans = last_unlink_trans;
4125 btrfs_end_transaction(trans);
4126 btrfs_btree_balance_dirty(root->fs_info);
4132 * Return this if we need to call truncate_block for the last bit of the
4135 #define NEED_TRUNCATE_BLOCK 1
4138 * this can truncate away extent items, csum items and directory items.
4139 * It starts at a high offset and removes keys until it can't find
4140 * any higher than new_size
4142 * csum items that cross the new i_size are truncated to the new size
4145 * min_type is the minimum key type to truncate down to. If set to 0, this
4146 * will kill all the items on this inode, including the INODE_ITEM_KEY.
4148 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
4149 struct btrfs_root *root,
4150 struct inode *inode,
4151 u64 new_size, u32 min_type)
4153 struct btrfs_fs_info *fs_info = root->fs_info;
4154 struct btrfs_path *path;
4155 struct extent_buffer *leaf;
4156 struct btrfs_file_extent_item *fi;
4157 struct btrfs_key key;
4158 struct btrfs_key found_key;
4159 u64 extent_start = 0;
4160 u64 extent_num_bytes = 0;
4161 u64 extent_offset = 0;
4163 u64 last_size = new_size;
4164 u32 found_type = (u8)-1;
4167 int pending_del_nr = 0;
4168 int pending_del_slot = 0;
4169 int extent_type = -1;
4171 u64 ino = btrfs_ino(BTRFS_I(inode));
4172 u64 bytes_deleted = 0;
4173 bool be_nice = false;
4174 bool should_throttle = false;
4175 const u64 lock_start = ALIGN_DOWN(new_size, fs_info->sectorsize);
4176 struct extent_state *cached_state = NULL;
4178 BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY);
4181 * For non-free space inodes and non-shareable roots, we want to back
4182 * off from time to time. This means all inodes in subvolume roots,
4183 * reloc roots, and data reloc roots.
4185 if (!btrfs_is_free_space_inode(BTRFS_I(inode)) &&
4186 test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
4189 path = btrfs_alloc_path();
4192 path->reada = READA_BACK;
4194 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4195 lock_extent_bits(&BTRFS_I(inode)->io_tree, lock_start, (u64)-1,
4199 * We want to drop from the next block forward in case this
4200 * new size is not block aligned since we will be keeping the
4201 * last block of the extent just the way it is.
4203 btrfs_drop_extent_cache(BTRFS_I(inode), ALIGN(new_size,
4204 fs_info->sectorsize),
4209 * This function is also used to drop the items in the log tree before
4210 * we relog the inode, so if root != BTRFS_I(inode)->root, it means
4211 * it is used to drop the logged items. So we shouldn't kill the delayed
4214 if (min_type == 0 && root == BTRFS_I(inode)->root)
4215 btrfs_kill_delayed_inode_items(BTRFS_I(inode));
4218 key.offset = (u64)-1;
4223 * with a 16K leaf size and 128MB extents, you can actually queue
4224 * up a huge file in a single leaf. Most of the time that
4225 * bytes_deleted is > 0, it will be huge by the time we get here
4227 if (be_nice && bytes_deleted > SZ_32M &&
4228 btrfs_should_end_transaction(trans)) {
4233 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
4239 /* there are no items in the tree for us to truncate, we're
4242 if (path->slots[0] == 0)
4248 u64 clear_start = 0, clear_len = 0;
4251 leaf = path->nodes[0];
4252 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
4253 found_type = found_key.type;
4255 if (found_key.objectid != ino)
4258 if (found_type < min_type)
4261 item_end = found_key.offset;
4262 if (found_type == BTRFS_EXTENT_DATA_KEY) {
4263 fi = btrfs_item_ptr(leaf, path->slots[0],
4264 struct btrfs_file_extent_item);
4265 extent_type = btrfs_file_extent_type(leaf, fi);
4266 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
4268 btrfs_file_extent_num_bytes(leaf, fi);
4270 trace_btrfs_truncate_show_fi_regular(
4271 BTRFS_I(inode), leaf, fi,
4273 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
4274 item_end += btrfs_file_extent_ram_bytes(leaf,
4277 trace_btrfs_truncate_show_fi_inline(
4278 BTRFS_I(inode), leaf, fi, path->slots[0],
4283 if (found_type > min_type) {
4286 if (item_end < new_size)
4288 if (found_key.offset >= new_size)
4294 /* FIXME, shrink the extent if the ref count is only 1 */
4295 if (found_type != BTRFS_EXTENT_DATA_KEY)
4298 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
4301 clear_start = found_key.offset;
4302 extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
4304 u64 orig_num_bytes =
4305 btrfs_file_extent_num_bytes(leaf, fi);
4306 extent_num_bytes = ALIGN(new_size -
4308 fs_info->sectorsize);
4309 clear_start = ALIGN(new_size, fs_info->sectorsize);
4310 btrfs_set_file_extent_num_bytes(leaf, fi,
4312 num_dec = (orig_num_bytes -
4314 if (test_bit(BTRFS_ROOT_SHAREABLE,
4317 inode_sub_bytes(inode, num_dec);
4318 btrfs_mark_buffer_dirty(leaf);
4321 btrfs_file_extent_disk_num_bytes(leaf,
4323 extent_offset = found_key.offset -
4324 btrfs_file_extent_offset(leaf, fi);
4326 /* FIXME blocksize != 4096 */
4327 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
4328 if (extent_start != 0) {
4330 if (test_bit(BTRFS_ROOT_SHAREABLE,
4332 inode_sub_bytes(inode, num_dec);
4335 clear_len = num_dec;
4336 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
4338 * we can't truncate inline items that have had
4342 btrfs_file_extent_encryption(leaf, fi) == 0 &&
4343 btrfs_file_extent_other_encoding(leaf, fi) == 0 &&
4344 btrfs_file_extent_compression(leaf, fi) == 0) {
4345 u32 size = (u32)(new_size - found_key.offset);
4347 btrfs_set_file_extent_ram_bytes(leaf, fi, size);
4348 size = btrfs_file_extent_calc_inline_size(size);
4349 btrfs_truncate_item(path, size, 1);
4350 } else if (!del_item) {
4352 * We have to bail so the last_size is set to
4353 * just before this extent.
4355 ret = NEED_TRUNCATE_BLOCK;
4359 * Inline extents are special, we just treat
4360 * them as a full sector worth in the file
4361 * extent tree just for simplicity sake.
4363 clear_len = fs_info->sectorsize;
4366 if (test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
4367 inode_sub_bytes(inode, item_end + 1 - new_size);
4371 * We use btrfs_truncate_inode_items() to clean up log trees for
4372 * multiple fsyncs, and in this case we don't want to clear the
4373 * file extent range because it's just the log.
4375 if (root == BTRFS_I(inode)->root) {
4376 ret = btrfs_inode_clear_file_extent_range(BTRFS_I(inode),
4377 clear_start, clear_len);
4379 btrfs_abort_transaction(trans, ret);
4385 last_size = found_key.offset;
4387 last_size = new_size;
4389 if (!pending_del_nr) {
4390 /* no pending yet, add ourselves */
4391 pending_del_slot = path->slots[0];
4393 } else if (pending_del_nr &&
4394 path->slots[0] + 1 == pending_del_slot) {
4395 /* hop on the pending chunk */
4397 pending_del_slot = path->slots[0];
4404 should_throttle = false;
4407 root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4408 struct btrfs_ref ref = { 0 };
4410 bytes_deleted += extent_num_bytes;
4412 btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF,
4413 extent_start, extent_num_bytes, 0);
4414 ref.real_root = root->root_key.objectid;
4415 btrfs_init_data_ref(&ref, btrfs_header_owner(leaf),
4416 ino, extent_offset);
4417 ret = btrfs_free_extent(trans, &ref);
4419 btrfs_abort_transaction(trans, ret);
4423 if (btrfs_should_throttle_delayed_refs(trans))
4424 should_throttle = true;
4428 if (found_type == BTRFS_INODE_ITEM_KEY)
4431 if (path->slots[0] == 0 ||
4432 path->slots[0] != pending_del_slot ||
4434 if (pending_del_nr) {
4435 ret = btrfs_del_items(trans, root, path,
4439 btrfs_abort_transaction(trans, ret);
4444 btrfs_release_path(path);
4447 * We can generate a lot of delayed refs, so we need to
4448 * throttle every once and a while and make sure we're
4449 * adding enough space to keep up with the work we are
4450 * generating. Since we hold a transaction here we
4451 * can't flush, and we don't want to FLUSH_LIMIT because
4452 * we could have generated too many delayed refs to
4453 * actually allocate, so just bail if we're short and
4454 * let the normal reservation dance happen higher up.
4456 if (should_throttle) {
4457 ret = btrfs_delayed_refs_rsv_refill(fs_info,
4458 BTRFS_RESERVE_NO_FLUSH);
4470 if (ret >= 0 && pending_del_nr) {
4473 err = btrfs_del_items(trans, root, path, pending_del_slot,
4476 btrfs_abort_transaction(trans, err);
4480 if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) {
4481 ASSERT(last_size >= new_size);
4482 if (!ret && last_size > new_size)
4483 last_size = new_size;
4484 btrfs_inode_safe_disk_i_size_write(inode, last_size);
4485 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lock_start,
4486 (u64)-1, &cached_state);
4489 btrfs_free_path(path);
4494 * btrfs_truncate_block - read, zero a chunk and write a block
4495 * @inode - inode that we're zeroing
4496 * @from - the offset to start zeroing
4497 * @len - the length to zero, 0 to zero the entire range respective to the
4499 * @front - zero up to the offset instead of from the offset on
4501 * This will find the block for the "from" offset and cow the block and zero the
4502 * part we want to zero. This is used with truncate and hole punching.
4504 int btrfs_truncate_block(struct inode *inode, loff_t from, loff_t len,
4507 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4508 struct address_space *mapping = inode->i_mapping;
4509 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4510 struct btrfs_ordered_extent *ordered;
4511 struct extent_state *cached_state = NULL;
4512 struct extent_changeset *data_reserved = NULL;
4514 u32 blocksize = fs_info->sectorsize;
4515 pgoff_t index = from >> PAGE_SHIFT;
4516 unsigned offset = from & (blocksize - 1);
4518 gfp_t mask = btrfs_alloc_write_mask(mapping);
4523 if (IS_ALIGNED(offset, blocksize) &&
4524 (!len || IS_ALIGNED(len, blocksize)))
4527 block_start = round_down(from, blocksize);
4528 block_end = block_start + blocksize - 1;
4530 ret = btrfs_delalloc_reserve_space(inode, &data_reserved,
4531 block_start, blocksize);
4536 page = find_or_create_page(mapping, index, mask);
4538 btrfs_delalloc_release_space(inode, data_reserved,
4539 block_start, blocksize, true);
4540 btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize);
4545 if (!PageUptodate(page)) {
4546 ret = btrfs_readpage(NULL, page);
4548 if (page->mapping != mapping) {
4553 if (!PageUptodate(page)) {
4558 wait_on_page_writeback(page);
4560 lock_extent_bits(io_tree, block_start, block_end, &cached_state);
4561 set_page_extent_mapped(page);
4563 ordered = btrfs_lookup_ordered_extent(inode, block_start);
4565 unlock_extent_cached(io_tree, block_start, block_end,
4569 btrfs_start_ordered_extent(inode, ordered, 1);
4570 btrfs_put_ordered_extent(ordered);
4574 clear_extent_bit(&BTRFS_I(inode)->io_tree, block_start, block_end,
4575 EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG,
4576 0, 0, &cached_state);
4578 ret = btrfs_set_extent_delalloc(inode, block_start, block_end, 0,
4581 unlock_extent_cached(io_tree, block_start, block_end,
4586 if (offset != blocksize) {
4588 len = blocksize - offset;
4591 memset(kaddr + (block_start - page_offset(page)),
4594 memset(kaddr + (block_start - page_offset(page)) + offset,
4596 flush_dcache_page(page);
4599 ClearPageChecked(page);
4600 set_page_dirty(page);
4601 unlock_extent_cached(io_tree, block_start, block_end, &cached_state);
4605 btrfs_delalloc_release_space(inode, data_reserved, block_start,
4607 btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize);
4611 extent_changeset_free(data_reserved);
4615 static int maybe_insert_hole(struct btrfs_root *root, struct inode *inode,
4616 u64 offset, u64 len)
4618 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4619 struct btrfs_trans_handle *trans;
4623 * Still need to make sure the inode looks like it's been updated so
4624 * that any holes get logged if we fsync.
4626 if (btrfs_fs_incompat(fs_info, NO_HOLES)) {
4627 BTRFS_I(inode)->last_trans = fs_info->generation;
4628 BTRFS_I(inode)->last_sub_trans = root->log_transid;
4629 BTRFS_I(inode)->last_log_commit = root->last_log_commit;
4634 * 1 - for the one we're dropping
4635 * 1 - for the one we're adding
4636 * 1 - for updating the inode.
4638 trans = btrfs_start_transaction(root, 3);
4640 return PTR_ERR(trans);
4642 ret = btrfs_drop_extents(trans, root, inode, offset, offset + len, 1);
4644 btrfs_abort_transaction(trans, ret);
4645 btrfs_end_transaction(trans);
4649 ret = btrfs_insert_file_extent(trans, root, btrfs_ino(BTRFS_I(inode)),
4650 offset, 0, 0, len, 0, len, 0, 0, 0);
4652 btrfs_abort_transaction(trans, ret);
4654 btrfs_update_inode(trans, root, inode);
4655 btrfs_end_transaction(trans);
4660 * This function puts in dummy file extents for the area we're creating a hole
4661 * for. So if we are truncating this file to a larger size we need to insert
4662 * these file extents so that btrfs_get_extent will return a EXTENT_MAP_HOLE for
4663 * the range between oldsize and size
4665 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
4667 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4668 struct btrfs_root *root = BTRFS_I(inode)->root;
4669 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4670 struct extent_map *em = NULL;
4671 struct extent_state *cached_state = NULL;
4672 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
4673 u64 hole_start = ALIGN(oldsize, fs_info->sectorsize);
4674 u64 block_end = ALIGN(size, fs_info->sectorsize);
4681 * If our size started in the middle of a block we need to zero out the
4682 * rest of the block before we expand the i_size, otherwise we could
4683 * expose stale data.
4685 err = btrfs_truncate_block(inode, oldsize, 0, 0);
4689 if (size <= hole_start)
4692 btrfs_lock_and_flush_ordered_range(BTRFS_I(inode), hole_start,
4693 block_end - 1, &cached_state);
4694 cur_offset = hole_start;
4696 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, cur_offset,
4697 block_end - cur_offset);
4703 last_byte = min(extent_map_end(em), block_end);
4704 last_byte = ALIGN(last_byte, fs_info->sectorsize);
4705 hole_size = last_byte - cur_offset;
4707 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags)) {
4708 struct extent_map *hole_em;
4710 err = maybe_insert_hole(root, inode, cur_offset,
4715 err = btrfs_inode_set_file_extent_range(BTRFS_I(inode),
4716 cur_offset, hole_size);
4720 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset,
4721 cur_offset + hole_size - 1, 0);
4722 hole_em = alloc_extent_map();
4724 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
4725 &BTRFS_I(inode)->runtime_flags);
4728 hole_em->start = cur_offset;
4729 hole_em->len = hole_size;
4730 hole_em->orig_start = cur_offset;
4732 hole_em->block_start = EXTENT_MAP_HOLE;
4733 hole_em->block_len = 0;
4734 hole_em->orig_block_len = 0;
4735 hole_em->ram_bytes = hole_size;
4736 hole_em->compress_type = BTRFS_COMPRESS_NONE;
4737 hole_em->generation = fs_info->generation;
4740 write_lock(&em_tree->lock);
4741 err = add_extent_mapping(em_tree, hole_em, 1);
4742 write_unlock(&em_tree->lock);
4745 btrfs_drop_extent_cache(BTRFS_I(inode),
4750 free_extent_map(hole_em);
4752 err = btrfs_inode_set_file_extent_range(BTRFS_I(inode),
4753 cur_offset, hole_size);
4758 free_extent_map(em);
4760 cur_offset = last_byte;
4761 if (cur_offset >= block_end)
4764 free_extent_map(em);
4765 unlock_extent_cached(io_tree, hole_start, block_end - 1, &cached_state);
4769 static int btrfs_setsize(struct inode *inode, struct iattr *attr)
4771 struct btrfs_root *root = BTRFS_I(inode)->root;
4772 struct btrfs_trans_handle *trans;
4773 loff_t oldsize = i_size_read(inode);
4774 loff_t newsize = attr->ia_size;
4775 int mask = attr->ia_valid;
4779 * The regular truncate() case without ATTR_CTIME and ATTR_MTIME is a
4780 * special case where we need to update the times despite not having
4781 * these flags set. For all other operations the VFS set these flags
4782 * explicitly if it wants a timestamp update.
4784 if (newsize != oldsize) {
4785 inode_inc_iversion(inode);
4786 if (!(mask & (ATTR_CTIME | ATTR_MTIME)))
4787 inode->i_ctime = inode->i_mtime =
4788 current_time(inode);
4791 if (newsize > oldsize) {
4793 * Don't do an expanding truncate while snapshotting is ongoing.
4794 * This is to ensure the snapshot captures a fully consistent
4795 * state of this file - if the snapshot captures this expanding
4796 * truncation, it must capture all writes that happened before
4799 btrfs_drew_write_lock(&root->snapshot_lock);
4800 ret = btrfs_cont_expand(inode, oldsize, newsize);
4802 btrfs_drew_write_unlock(&root->snapshot_lock);
4806 trans = btrfs_start_transaction(root, 1);
4807 if (IS_ERR(trans)) {
4808 btrfs_drew_write_unlock(&root->snapshot_lock);
4809 return PTR_ERR(trans);
4812 i_size_write(inode, newsize);
4813 btrfs_inode_safe_disk_i_size_write(inode, 0);
4814 pagecache_isize_extended(inode, oldsize, newsize);
4815 ret = btrfs_update_inode(trans, root, inode);
4816 btrfs_drew_write_unlock(&root->snapshot_lock);
4817 btrfs_end_transaction(trans);
4821 * We're truncating a file that used to have good data down to
4822 * zero. Make sure it gets into the ordered flush list so that
4823 * any new writes get down to disk quickly.
4826 set_bit(BTRFS_INODE_ORDERED_DATA_CLOSE,
4827 &BTRFS_I(inode)->runtime_flags);
4829 truncate_setsize(inode, newsize);
4831 /* Disable nonlocked read DIO to avoid the endless truncate */
4832 btrfs_inode_block_unlocked_dio(BTRFS_I(inode));
4833 inode_dio_wait(inode);
4834 btrfs_inode_resume_unlocked_dio(BTRFS_I(inode));
4836 ret = btrfs_truncate(inode, newsize == oldsize);
4837 if (ret && inode->i_nlink) {
4841 * Truncate failed, so fix up the in-memory size. We
4842 * adjusted disk_i_size down as we removed extents, so
4843 * wait for disk_i_size to be stable and then update the
4844 * in-memory size to match.
4846 err = btrfs_wait_ordered_range(inode, 0, (u64)-1);
4849 i_size_write(inode, BTRFS_I(inode)->disk_i_size);
4856 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
4858 struct inode *inode = d_inode(dentry);
4859 struct btrfs_root *root = BTRFS_I(inode)->root;
4862 if (btrfs_root_readonly(root))
4865 err = setattr_prepare(dentry, attr);
4869 if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
4870 err = btrfs_setsize(inode, attr);
4875 if (attr->ia_valid) {
4876 setattr_copy(inode, attr);
4877 inode_inc_iversion(inode);
4878 err = btrfs_dirty_inode(inode);
4880 if (!err && attr->ia_valid & ATTR_MODE)
4881 err = posix_acl_chmod(inode, inode->i_mode);
4888 * While truncating the inode pages during eviction, we get the VFS calling
4889 * btrfs_invalidatepage() against each page of the inode. This is slow because
4890 * the calls to btrfs_invalidatepage() result in a huge amount of calls to
4891 * lock_extent_bits() and clear_extent_bit(), which keep merging and splitting
4892 * extent_state structures over and over, wasting lots of time.
4894 * Therefore if the inode is being evicted, let btrfs_invalidatepage() skip all
4895 * those expensive operations on a per page basis and do only the ordered io
4896 * finishing, while we release here the extent_map and extent_state structures,
4897 * without the excessive merging and splitting.
4899 static void evict_inode_truncate_pages(struct inode *inode)
4901 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
4902 struct extent_map_tree *map_tree = &BTRFS_I(inode)->extent_tree;
4903 struct rb_node *node;
4905 ASSERT(inode->i_state & I_FREEING);
4906 truncate_inode_pages_final(&inode->i_data);
4908 write_lock(&map_tree->lock);
4909 while (!RB_EMPTY_ROOT(&map_tree->map.rb_root)) {
4910 struct extent_map *em;
4912 node = rb_first_cached(&map_tree->map);
4913 em = rb_entry(node, struct extent_map, rb_node);
4914 clear_bit(EXTENT_FLAG_PINNED, &em->flags);
4915 clear_bit(EXTENT_FLAG_LOGGING, &em->flags);
4916 remove_extent_mapping(map_tree, em);
4917 free_extent_map(em);
4918 if (need_resched()) {
4919 write_unlock(&map_tree->lock);
4921 write_lock(&map_tree->lock);
4924 write_unlock(&map_tree->lock);
4927 * Keep looping until we have no more ranges in the io tree.
4928 * We can have ongoing bios started by readpages (called from readahead)
4929 * that have their endio callback (extent_io.c:end_bio_extent_readpage)
4930 * still in progress (unlocked the pages in the bio but did not yet
4931 * unlocked the ranges in the io tree). Therefore this means some
4932 * ranges can still be locked and eviction started because before
4933 * submitting those bios, which are executed by a separate task (work
4934 * queue kthread), inode references (inode->i_count) were not taken
4935 * (which would be dropped in the end io callback of each bio).
4936 * Therefore here we effectively end up waiting for those bios and
4937 * anyone else holding locked ranges without having bumped the inode's
4938 * reference count - if we don't do it, when they access the inode's
4939 * io_tree to unlock a range it may be too late, leading to an
4940 * use-after-free issue.
4942 spin_lock(&io_tree->lock);
4943 while (!RB_EMPTY_ROOT(&io_tree->state)) {
4944 struct extent_state *state;
4945 struct extent_state *cached_state = NULL;
4948 unsigned state_flags;
4950 node = rb_first(&io_tree->state);
4951 state = rb_entry(node, struct extent_state, rb_node);
4952 start = state->start;
4954 state_flags = state->state;
4955 spin_unlock(&io_tree->lock);
4957 lock_extent_bits(io_tree, start, end, &cached_state);
4960 * If still has DELALLOC flag, the extent didn't reach disk,
4961 * and its reserved space won't be freed by delayed_ref.
4962 * So we need to free its reserved space here.
4963 * (Refer to comment in btrfs_invalidatepage, case 2)
4965 * Note, end is the bytenr of last byte, so we need + 1 here.
4967 if (state_flags & EXTENT_DELALLOC)
4968 btrfs_qgroup_free_data(inode, NULL, start, end - start + 1);
4970 clear_extent_bit(io_tree, start, end,
4971 EXTENT_LOCKED | EXTENT_DELALLOC |
4972 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 1, 1,
4976 spin_lock(&io_tree->lock);
4978 spin_unlock(&io_tree->lock);
4981 static struct btrfs_trans_handle *evict_refill_and_join(struct btrfs_root *root,
4982 struct btrfs_block_rsv *rsv)
4984 struct btrfs_fs_info *fs_info = root->fs_info;
4985 struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
4986 struct btrfs_trans_handle *trans;
4987 u64 delayed_refs_extra = btrfs_calc_insert_metadata_size(fs_info, 1);
4991 * Eviction should be taking place at some place safe because of our
4992 * delayed iputs. However the normal flushing code will run delayed
4993 * iputs, so we cannot use FLUSH_ALL otherwise we'll deadlock.
4995 * We reserve the delayed_refs_extra here again because we can't use
4996 * btrfs_start_transaction(root, 0) for the same deadlocky reason as
4997 * above. We reserve our extra bit here because we generate a ton of
4998 * delayed refs activity by truncating.
5000 * If we cannot make our reservation we'll attempt to steal from the
5001 * global reserve, because we really want to be able to free up space.
5003 ret = btrfs_block_rsv_refill(root, rsv, rsv->size + delayed_refs_extra,
5004 BTRFS_RESERVE_FLUSH_EVICT);
5007 * Try to steal from the global reserve if there is space for
5010 if (btrfs_check_space_for_delayed_refs(fs_info) ||
5011 btrfs_block_rsv_migrate(global_rsv, rsv, rsv->size, 0)) {
5013 "could not allocate space for delete; will truncate on mount");
5014 return ERR_PTR(-ENOSPC);
5016 delayed_refs_extra = 0;
5019 trans = btrfs_join_transaction(root);
5023 if (delayed_refs_extra) {
5024 trans->block_rsv = &fs_info->trans_block_rsv;
5025 trans->bytes_reserved = delayed_refs_extra;
5026 btrfs_block_rsv_migrate(rsv, trans->block_rsv,
5027 delayed_refs_extra, 1);
5032 void btrfs_evict_inode(struct inode *inode)
5034 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5035 struct btrfs_trans_handle *trans;
5036 struct btrfs_root *root = BTRFS_I(inode)->root;
5037 struct btrfs_block_rsv *rsv;
5040 trace_btrfs_inode_evict(inode);
5047 evict_inode_truncate_pages(inode);
5049 if (inode->i_nlink &&
5050 ((btrfs_root_refs(&root->root_item) != 0 &&
5051 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID) ||
5052 btrfs_is_free_space_inode(BTRFS_I(inode))))
5055 if (is_bad_inode(inode))
5058 btrfs_free_io_failure_record(BTRFS_I(inode), 0, (u64)-1);
5060 if (test_bit(BTRFS_FS_LOG_RECOVERING, &fs_info->flags))
5063 if (inode->i_nlink > 0) {
5064 BUG_ON(btrfs_root_refs(&root->root_item) != 0 &&
5065 root->root_key.objectid != BTRFS_ROOT_TREE_OBJECTID);
5069 ret = btrfs_commit_inode_delayed_inode(BTRFS_I(inode));
5073 rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP);
5076 rsv->size = btrfs_calc_metadata_size(fs_info, 1);
5079 btrfs_i_size_write(BTRFS_I(inode), 0);
5082 trans = evict_refill_and_join(root, rsv);
5086 trans->block_rsv = rsv;
5088 ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
5089 trans->block_rsv = &fs_info->trans_block_rsv;
5090 btrfs_end_transaction(trans);
5091 btrfs_btree_balance_dirty(fs_info);
5092 if (ret && ret != -ENOSPC && ret != -EAGAIN)
5099 * Errors here aren't a big deal, it just means we leave orphan items in
5100 * the tree. They will be cleaned up on the next mount. If the inode
5101 * number gets reused, cleanup deletes the orphan item without doing
5102 * anything, and unlink reuses the existing orphan item.
5104 * If it turns out that we are dropping too many of these, we might want
5105 * to add a mechanism for retrying these after a commit.
5107 trans = evict_refill_and_join(root, rsv);
5108 if (!IS_ERR(trans)) {
5109 trans->block_rsv = rsv;
5110 btrfs_orphan_del(trans, BTRFS_I(inode));
5111 trans->block_rsv = &fs_info->trans_block_rsv;
5112 btrfs_end_transaction(trans);
5115 if (!(root == fs_info->tree_root ||
5116 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID))
5117 btrfs_return_ino(root, btrfs_ino(BTRFS_I(inode)));
5120 btrfs_free_block_rsv(fs_info, rsv);
5123 * If we didn't successfully delete, the orphan item will still be in
5124 * the tree and we'll retry on the next mount. Again, we might also want
5125 * to retry these periodically in the future.
5127 btrfs_remove_delayed_node(BTRFS_I(inode));
5132 * Return the key found in the dir entry in the location pointer, fill @type
5133 * with BTRFS_FT_*, and return 0.
5135 * If no dir entries were found, returns -ENOENT.
5136 * If found a corrupted location in dir entry, returns -EUCLEAN.
5138 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
5139 struct btrfs_key *location, u8 *type)
5141 const char *name = dentry->d_name.name;
5142 int namelen = dentry->d_name.len;
5143 struct btrfs_dir_item *di;
5144 struct btrfs_path *path;
5145 struct btrfs_root *root = BTRFS_I(dir)->root;
5148 path = btrfs_alloc_path();
5152 di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(BTRFS_I(dir)),
5154 if (IS_ERR_OR_NULL(di)) {
5155 ret = di ? PTR_ERR(di) : -ENOENT;
5159 btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
5160 if (location->type != BTRFS_INODE_ITEM_KEY &&
5161 location->type != BTRFS_ROOT_ITEM_KEY) {
5163 btrfs_warn(root->fs_info,
5164 "%s gets something invalid in DIR_ITEM (name %s, directory ino %llu, location(%llu %u %llu))",
5165 __func__, name, btrfs_ino(BTRFS_I(dir)),
5166 location->objectid, location->type, location->offset);
5169 *type = btrfs_dir_type(path->nodes[0], di);
5171 btrfs_free_path(path);
5176 * when we hit a tree root in a directory, the btrfs part of the inode
5177 * needs to be changed to reflect the root directory of the tree root. This
5178 * is kind of like crossing a mount point.
5180 static int fixup_tree_root_location(struct btrfs_fs_info *fs_info,
5182 struct dentry *dentry,
5183 struct btrfs_key *location,
5184 struct btrfs_root **sub_root)
5186 struct btrfs_path *path;
5187 struct btrfs_root *new_root;
5188 struct btrfs_root_ref *ref;
5189 struct extent_buffer *leaf;
5190 struct btrfs_key key;
5194 path = btrfs_alloc_path();
5201 key.objectid = BTRFS_I(dir)->root->root_key.objectid;
5202 key.type = BTRFS_ROOT_REF_KEY;
5203 key.offset = location->objectid;
5205 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
5212 leaf = path->nodes[0];
5213 ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
5214 if (btrfs_root_ref_dirid(leaf, ref) != btrfs_ino(BTRFS_I(dir)) ||
5215 btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
5218 ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
5219 (unsigned long)(ref + 1),
5220 dentry->d_name.len);
5224 btrfs_release_path(path);
5226 new_root = btrfs_get_fs_root(fs_info, location->objectid, true);
5227 if (IS_ERR(new_root)) {
5228 err = PTR_ERR(new_root);
5232 *sub_root = new_root;
5233 location->objectid = btrfs_root_dirid(&new_root->root_item);
5234 location->type = BTRFS_INODE_ITEM_KEY;
5235 location->offset = 0;
5238 btrfs_free_path(path);
5242 static void inode_tree_add(struct inode *inode)
5244 struct btrfs_root *root = BTRFS_I(inode)->root;
5245 struct btrfs_inode *entry;
5247 struct rb_node *parent;
5248 struct rb_node *new = &BTRFS_I(inode)->rb_node;
5249 u64 ino = btrfs_ino(BTRFS_I(inode));
5251 if (inode_unhashed(inode))
5254 spin_lock(&root->inode_lock);
5255 p = &root->inode_tree.rb_node;
5258 entry = rb_entry(parent, struct btrfs_inode, rb_node);
5260 if (ino < btrfs_ino(entry))
5261 p = &parent->rb_left;
5262 else if (ino > btrfs_ino(entry))
5263 p = &parent->rb_right;
5265 WARN_ON(!(entry->vfs_inode.i_state &
5266 (I_WILL_FREE | I_FREEING)));
5267 rb_replace_node(parent, new, &root->inode_tree);
5268 RB_CLEAR_NODE(parent);
5269 spin_unlock(&root->inode_lock);
5273 rb_link_node(new, parent, p);
5274 rb_insert_color(new, &root->inode_tree);
5275 spin_unlock(&root->inode_lock);
5278 static void inode_tree_del(struct inode *inode)
5280 struct btrfs_root *root = BTRFS_I(inode)->root;
5283 spin_lock(&root->inode_lock);
5284 if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
5285 rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
5286 RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
5287 empty = RB_EMPTY_ROOT(&root->inode_tree);
5289 spin_unlock(&root->inode_lock);
5291 if (empty && btrfs_root_refs(&root->root_item) == 0) {
5292 spin_lock(&root->inode_lock);
5293 empty = RB_EMPTY_ROOT(&root->inode_tree);
5294 spin_unlock(&root->inode_lock);
5296 btrfs_add_dead_root(root);
5301 static int btrfs_init_locked_inode(struct inode *inode, void *p)
5303 struct btrfs_iget_args *args = p;
5305 inode->i_ino = args->ino;
5306 BTRFS_I(inode)->location.objectid = args->ino;
5307 BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
5308 BTRFS_I(inode)->location.offset = 0;
5309 BTRFS_I(inode)->root = btrfs_grab_root(args->root);
5310 BUG_ON(args->root && !BTRFS_I(inode)->root);
5314 static int btrfs_find_actor(struct inode *inode, void *opaque)
5316 struct btrfs_iget_args *args = opaque;
5318 return args->ino == BTRFS_I(inode)->location.objectid &&
5319 args->root == BTRFS_I(inode)->root;
5322 static struct inode *btrfs_iget_locked(struct super_block *s, u64 ino,
5323 struct btrfs_root *root)
5325 struct inode *inode;
5326 struct btrfs_iget_args args;
5327 unsigned long hashval = btrfs_inode_hash(ino, root);
5332 inode = iget5_locked(s, hashval, btrfs_find_actor,
5333 btrfs_init_locked_inode,
5339 * Get an inode object given its inode number and corresponding root.
5340 * Path can be preallocated to prevent recursing back to iget through
5341 * allocator. NULL is also valid but may require an additional allocation
5344 struct inode *btrfs_iget_path(struct super_block *s, u64 ino,
5345 struct btrfs_root *root, struct btrfs_path *path)
5347 struct inode *inode;
5349 inode = btrfs_iget_locked(s, ino, root);
5351 return ERR_PTR(-ENOMEM);
5353 if (inode->i_state & I_NEW) {
5356 ret = btrfs_read_locked_inode(inode, path);
5358 inode_tree_add(inode);
5359 unlock_new_inode(inode);
5363 * ret > 0 can come from btrfs_search_slot called by
5364 * btrfs_read_locked_inode, this means the inode item
5369 inode = ERR_PTR(ret);
5376 struct inode *btrfs_iget(struct super_block *s, u64 ino, struct btrfs_root *root)
5378 return btrfs_iget_path(s, ino, root, NULL);
5381 static struct inode *new_simple_dir(struct super_block *s,
5382 struct btrfs_key *key,
5383 struct btrfs_root *root)
5385 struct inode *inode = new_inode(s);
5388 return ERR_PTR(-ENOMEM);
5390 BTRFS_I(inode)->root = btrfs_grab_root(root);
5391 memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
5392 set_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags);
5394 inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
5396 * We only need lookup, the rest is read-only and there's no inode
5397 * associated with the dentry
5399 inode->i_op = &simple_dir_inode_operations;
5400 inode->i_opflags &= ~IOP_XATTR;
5401 inode->i_fop = &simple_dir_operations;
5402 inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
5403 inode->i_mtime = current_time(inode);
5404 inode->i_atime = inode->i_mtime;
5405 inode->i_ctime = inode->i_mtime;
5406 BTRFS_I(inode)->i_otime = inode->i_mtime;
5411 static inline u8 btrfs_inode_type(struct inode *inode)
5414 * Compile-time asserts that generic FT_* types still match
5417 BUILD_BUG_ON(BTRFS_FT_UNKNOWN != FT_UNKNOWN);
5418 BUILD_BUG_ON(BTRFS_FT_REG_FILE != FT_REG_FILE);
5419 BUILD_BUG_ON(BTRFS_FT_DIR != FT_DIR);
5420 BUILD_BUG_ON(BTRFS_FT_CHRDEV != FT_CHRDEV);
5421 BUILD_BUG_ON(BTRFS_FT_BLKDEV != FT_BLKDEV);
5422 BUILD_BUG_ON(BTRFS_FT_FIFO != FT_FIFO);
5423 BUILD_BUG_ON(BTRFS_FT_SOCK != FT_SOCK);
5424 BUILD_BUG_ON(BTRFS_FT_SYMLINK != FT_SYMLINK);
5426 return fs_umode_to_ftype(inode->i_mode);
5429 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
5431 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
5432 struct inode *inode;
5433 struct btrfs_root *root = BTRFS_I(dir)->root;
5434 struct btrfs_root *sub_root = root;
5435 struct btrfs_key location;
5439 if (dentry->d_name.len > BTRFS_NAME_LEN)
5440 return ERR_PTR(-ENAMETOOLONG);
5442 ret = btrfs_inode_by_name(dir, dentry, &location, &di_type);
5444 return ERR_PTR(ret);
5446 if (location.type == BTRFS_INODE_ITEM_KEY) {
5447 inode = btrfs_iget(dir->i_sb, location.objectid, root);
5451 /* Do extra check against inode mode with di_type */
5452 if (btrfs_inode_type(inode) != di_type) {
5454 "inode mode mismatch with dir: inode mode=0%o btrfs type=%u dir type=%u",
5455 inode->i_mode, btrfs_inode_type(inode),
5458 return ERR_PTR(-EUCLEAN);
5463 ret = fixup_tree_root_location(fs_info, dir, dentry,
5464 &location, &sub_root);
5467 inode = ERR_PTR(ret);
5469 inode = new_simple_dir(dir->i_sb, &location, sub_root);
5471 inode = btrfs_iget(dir->i_sb, location.objectid, sub_root);
5473 if (root != sub_root)
5474 btrfs_put_root(sub_root);
5476 if (!IS_ERR(inode) && root != sub_root) {
5477 down_read(&fs_info->cleanup_work_sem);
5478 if (!sb_rdonly(inode->i_sb))
5479 ret = btrfs_orphan_cleanup(sub_root);
5480 up_read(&fs_info->cleanup_work_sem);
5483 inode = ERR_PTR(ret);
5490 static int btrfs_dentry_delete(const struct dentry *dentry)
5492 struct btrfs_root *root;
5493 struct inode *inode = d_inode(dentry);
5495 if (!inode && !IS_ROOT(dentry))
5496 inode = d_inode(dentry->d_parent);
5499 root = BTRFS_I(inode)->root;
5500 if (btrfs_root_refs(&root->root_item) == 0)
5503 if (btrfs_ino(BTRFS_I(inode)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
5509 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
5512 struct inode *inode = btrfs_lookup_dentry(dir, dentry);
5514 if (inode == ERR_PTR(-ENOENT))
5516 return d_splice_alias(inode, dentry);
5520 * All this infrastructure exists because dir_emit can fault, and we are holding
5521 * the tree lock when doing readdir. For now just allocate a buffer and copy
5522 * our information into that, and then dir_emit from the buffer. This is
5523 * similar to what NFS does, only we don't keep the buffer around in pagecache
5524 * because I'm afraid I'll mess that up. Long term we need to make filldir do
5525 * copy_to_user_inatomic so we don't have to worry about page faulting under the
5528 static int btrfs_opendir(struct inode *inode, struct file *file)
5530 struct btrfs_file_private *private;
5532 private = kzalloc(sizeof(struct btrfs_file_private), GFP_KERNEL);
5535 private->filldir_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
5536 if (!private->filldir_buf) {
5540 file->private_data = private;
5551 static int btrfs_filldir(void *addr, int entries, struct dir_context *ctx)
5554 struct dir_entry *entry = addr;
5555 char *name = (char *)(entry + 1);
5557 ctx->pos = get_unaligned(&entry->offset);
5558 if (!dir_emit(ctx, name, get_unaligned(&entry->name_len),
5559 get_unaligned(&entry->ino),
5560 get_unaligned(&entry->type)))
5562 addr += sizeof(struct dir_entry) +
5563 get_unaligned(&entry->name_len);
5569 static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
5571 struct inode *inode = file_inode(file);
5572 struct btrfs_root *root = BTRFS_I(inode)->root;
5573 struct btrfs_file_private *private = file->private_data;
5574 struct btrfs_dir_item *di;
5575 struct btrfs_key key;
5576 struct btrfs_key found_key;
5577 struct btrfs_path *path;
5579 struct list_head ins_list;
5580 struct list_head del_list;
5582 struct extent_buffer *leaf;
5589 struct btrfs_key location;
5591 if (!dir_emit_dots(file, ctx))
5594 path = btrfs_alloc_path();
5598 addr = private->filldir_buf;
5599 path->reada = READA_FORWARD;
5601 INIT_LIST_HEAD(&ins_list);
5602 INIT_LIST_HEAD(&del_list);
5603 put = btrfs_readdir_get_delayed_items(inode, &ins_list, &del_list);
5606 key.type = BTRFS_DIR_INDEX_KEY;
5607 key.offset = ctx->pos;
5608 key.objectid = btrfs_ino(BTRFS_I(inode));
5610 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5615 struct dir_entry *entry;
5617 leaf = path->nodes[0];
5618 slot = path->slots[0];
5619 if (slot >= btrfs_header_nritems(leaf)) {
5620 ret = btrfs_next_leaf(root, path);
5628 btrfs_item_key_to_cpu(leaf, &found_key, slot);
5630 if (found_key.objectid != key.objectid)
5632 if (found_key.type != BTRFS_DIR_INDEX_KEY)
5634 if (found_key.offset < ctx->pos)
5636 if (btrfs_should_delete_dir_index(&del_list, found_key.offset))
5638 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
5639 name_len = btrfs_dir_name_len(leaf, di);
5640 if ((total_len + sizeof(struct dir_entry) + name_len) >=
5642 btrfs_release_path(path);
5643 ret = btrfs_filldir(private->filldir_buf, entries, ctx);
5646 addr = private->filldir_buf;
5653 put_unaligned(name_len, &entry->name_len);
5654 name_ptr = (char *)(entry + 1);
5655 read_extent_buffer(leaf, name_ptr, (unsigned long)(di + 1),
5657 put_unaligned(fs_ftype_to_dtype(btrfs_dir_type(leaf, di)),
5659 btrfs_dir_item_key_to_cpu(leaf, di, &location);
5660 put_unaligned(location.objectid, &entry->ino);
5661 put_unaligned(found_key.offset, &entry->offset);
5663 addr += sizeof(struct dir_entry) + name_len;
5664 total_len += sizeof(struct dir_entry) + name_len;
5668 btrfs_release_path(path);
5670 ret = btrfs_filldir(private->filldir_buf, entries, ctx);
5674 ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list);
5679 * Stop new entries from being returned after we return the last
5682 * New directory entries are assigned a strictly increasing
5683 * offset. This means that new entries created during readdir
5684 * are *guaranteed* to be seen in the future by that readdir.
5685 * This has broken buggy programs which operate on names as
5686 * they're returned by readdir. Until we re-use freed offsets
5687 * we have this hack to stop new entries from being returned
5688 * under the assumption that they'll never reach this huge
5691 * This is being careful not to overflow 32bit loff_t unless the
5692 * last entry requires it because doing so has broken 32bit apps
5695 if (ctx->pos >= INT_MAX)
5696 ctx->pos = LLONG_MAX;
5703 btrfs_readdir_put_delayed_items(inode, &ins_list, &del_list);
5704 btrfs_free_path(path);
5709 * This is somewhat expensive, updating the tree every time the
5710 * inode changes. But, it is most likely to find the inode in cache.
5711 * FIXME, needs more benchmarking...there are no reasons other than performance
5712 * to keep or drop this code.
5714 static int btrfs_dirty_inode(struct inode *inode)
5716 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
5717 struct btrfs_root *root = BTRFS_I(inode)->root;
5718 struct btrfs_trans_handle *trans;
5721 if (test_bit(BTRFS_INODE_DUMMY, &BTRFS_I(inode)->runtime_flags))
5724 trans = btrfs_join_transaction(root);
5726 return PTR_ERR(trans);
5728 ret = btrfs_update_inode(trans, root, inode);
5729 if (ret && ret == -ENOSPC) {
5730 /* whoops, lets try again with the full transaction */
5731 btrfs_end_transaction(trans);
5732 trans = btrfs_start_transaction(root, 1);
5734 return PTR_ERR(trans);
5736 ret = btrfs_update_inode(trans, root, inode);
5738 btrfs_end_transaction(trans);
5739 if (BTRFS_I(inode)->delayed_node)
5740 btrfs_balance_delayed_items(fs_info);
5746 * This is a copy of file_update_time. We need this so we can return error on
5747 * ENOSPC for updating the inode in the case of file write and mmap writes.
5749 static int btrfs_update_time(struct inode *inode, struct timespec64 *now,
5752 struct btrfs_root *root = BTRFS_I(inode)->root;
5753 bool dirty = flags & ~S_VERSION;
5755 if (btrfs_root_readonly(root))
5758 if (flags & S_VERSION)
5759 dirty |= inode_maybe_inc_iversion(inode, dirty);
5760 if (flags & S_CTIME)
5761 inode->i_ctime = *now;
5762 if (flags & S_MTIME)
5763 inode->i_mtime = *now;
5764 if (flags & S_ATIME)
5765 inode->i_atime = *now;
5766 return dirty ? btrfs_dirty_inode(inode) : 0;
5770 * find the highest existing sequence number in a directory
5771 * and then set the in-memory index_cnt variable to reflect
5772 * free sequence numbers
5774 static int btrfs_set_inode_index_count(struct btrfs_inode *inode)
5776 struct btrfs_root *root = inode->root;
5777 struct btrfs_key key, found_key;
5778 struct btrfs_path *path;
5779 struct extent_buffer *leaf;
5782 key.objectid = btrfs_ino(inode);
5783 key.type = BTRFS_DIR_INDEX_KEY;
5784 key.offset = (u64)-1;
5786 path = btrfs_alloc_path();
5790 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5793 /* FIXME: we should be able to handle this */
5799 * MAGIC NUMBER EXPLANATION:
5800 * since we search a directory based on f_pos we have to start at 2
5801 * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
5802 * else has to start at 2
5804 if (path->slots[0] == 0) {
5805 inode->index_cnt = 2;
5811 leaf = path->nodes[0];
5812 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
5814 if (found_key.objectid != btrfs_ino(inode) ||
5815 found_key.type != BTRFS_DIR_INDEX_KEY) {
5816 inode->index_cnt = 2;
5820 inode->index_cnt = found_key.offset + 1;
5822 btrfs_free_path(path);
5827 * helper to find a free sequence number in a given directory. This current
5828 * code is very simple, later versions will do smarter things in the btree
5830 int btrfs_set_inode_index(struct btrfs_inode *dir, u64 *index)
5834 if (dir->index_cnt == (u64)-1) {
5835 ret = btrfs_inode_delayed_dir_index_count(dir);
5837 ret = btrfs_set_inode_index_count(dir);
5843 *index = dir->index_cnt;
5849 static int btrfs_insert_inode_locked(struct inode *inode)
5851 struct btrfs_iget_args args;
5853 args.ino = BTRFS_I(inode)->location.objectid;
5854 args.root = BTRFS_I(inode)->root;
5856 return insert_inode_locked4(inode,
5857 btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root),
5858 btrfs_find_actor, &args);
5862 * Inherit flags from the parent inode.
5864 * Currently only the compression flags and the cow flags are inherited.
5866 static void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
5873 flags = BTRFS_I(dir)->flags;
5875 if (flags & BTRFS_INODE_NOCOMPRESS) {
5876 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
5877 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
5878 } else if (flags & BTRFS_INODE_COMPRESS) {
5879 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
5880 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
5883 if (flags & BTRFS_INODE_NODATACOW) {
5884 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
5885 if (S_ISREG(inode->i_mode))
5886 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
5889 btrfs_sync_inode_flags_to_i_flags(inode);
5892 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
5893 struct btrfs_root *root,
5895 const char *name, int name_len,
5896 u64 ref_objectid, u64 objectid,
5897 umode_t mode, u64 *index)
5899 struct btrfs_fs_info *fs_info = root->fs_info;
5900 struct inode *inode;
5901 struct btrfs_inode_item *inode_item;
5902 struct btrfs_key *location;
5903 struct btrfs_path *path;
5904 struct btrfs_inode_ref *ref;
5905 struct btrfs_key key[2];
5907 int nitems = name ? 2 : 1;
5909 unsigned int nofs_flag;
5912 path = btrfs_alloc_path();
5914 return ERR_PTR(-ENOMEM);
5916 nofs_flag = memalloc_nofs_save();
5917 inode = new_inode(fs_info->sb);
5918 memalloc_nofs_restore(nofs_flag);
5920 btrfs_free_path(path);
5921 return ERR_PTR(-ENOMEM);
5925 * O_TMPFILE, set link count to 0, so that after this point,
5926 * we fill in an inode item with the correct link count.
5929 set_nlink(inode, 0);
5932 * we have to initialize this early, so we can reclaim the inode
5933 * number if we fail afterwards in this function.
5935 inode->i_ino = objectid;
5938 trace_btrfs_inode_request(dir);
5940 ret = btrfs_set_inode_index(BTRFS_I(dir), index);
5942 btrfs_free_path(path);
5944 return ERR_PTR(ret);
5950 * index_cnt is ignored for everything but a dir,
5951 * btrfs_set_inode_index_count has an explanation for the magic
5954 BTRFS_I(inode)->index_cnt = 2;
5955 BTRFS_I(inode)->dir_index = *index;
5956 BTRFS_I(inode)->root = btrfs_grab_root(root);
5957 BTRFS_I(inode)->generation = trans->transid;
5958 inode->i_generation = BTRFS_I(inode)->generation;
5961 * We could have gotten an inode number from somebody who was fsynced
5962 * and then removed in this same transaction, so let's just set full
5963 * sync since it will be a full sync anyway and this will blow away the
5964 * old info in the log.
5966 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
5968 key[0].objectid = objectid;
5969 key[0].type = BTRFS_INODE_ITEM_KEY;
5972 sizes[0] = sizeof(struct btrfs_inode_item);
5976 * Start new inodes with an inode_ref. This is slightly more
5977 * efficient for small numbers of hard links since they will
5978 * be packed into one item. Extended refs will kick in if we
5979 * add more hard links than can fit in the ref item.
5981 key[1].objectid = objectid;
5982 key[1].type = BTRFS_INODE_REF_KEY;
5983 key[1].offset = ref_objectid;
5985 sizes[1] = name_len + sizeof(*ref);
5988 location = &BTRFS_I(inode)->location;
5989 location->objectid = objectid;
5990 location->offset = 0;
5991 location->type = BTRFS_INODE_ITEM_KEY;
5993 ret = btrfs_insert_inode_locked(inode);
5999 path->leave_spinning = 1;
6000 ret = btrfs_insert_empty_items(trans, root, path, key, sizes, nitems);
6004 inode_init_owner(inode, dir, mode);
6005 inode_set_bytes(inode, 0);
6007 inode->i_mtime = current_time(inode);
6008 inode->i_atime = inode->i_mtime;
6009 inode->i_ctime = inode->i_mtime;
6010 BTRFS_I(inode)->i_otime = inode->i_mtime;
6012 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
6013 struct btrfs_inode_item);
6014 memzero_extent_buffer(path->nodes[0], (unsigned long)inode_item,
6015 sizeof(*inode_item));
6016 fill_inode_item(trans, path->nodes[0], inode_item, inode);
6019 ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
6020 struct btrfs_inode_ref);
6021 btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
6022 btrfs_set_inode_ref_index(path->nodes[0], ref, *index);
6023 ptr = (unsigned long)(ref + 1);
6024 write_extent_buffer(path->nodes[0], name, ptr, name_len);
6027 btrfs_mark_buffer_dirty(path->nodes[0]);
6028 btrfs_free_path(path);
6030 btrfs_inherit_iflags(inode, dir);
6032 if (S_ISREG(mode)) {
6033 if (btrfs_test_opt(fs_info, NODATASUM))
6034 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
6035 if (btrfs_test_opt(fs_info, NODATACOW))
6036 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW |
6037 BTRFS_INODE_NODATASUM;
6040 inode_tree_add(inode);
6042 trace_btrfs_inode_new(inode);
6043 btrfs_set_inode_last_trans(trans, inode);
6045 btrfs_update_root_times(trans, root);
6047 ret = btrfs_inode_inherit_props(trans, inode, dir);
6050 "error inheriting props for ino %llu (root %llu): %d",
6051 btrfs_ino(BTRFS_I(inode)), root->root_key.objectid, ret);
6056 discard_new_inode(inode);
6059 BTRFS_I(dir)->index_cnt--;
6060 btrfs_free_path(path);
6061 return ERR_PTR(ret);
6065 * utility function to add 'inode' into 'parent_inode' with
6066 * a give name and a given sequence number.
6067 * if 'add_backref' is true, also insert a backref from the
6068 * inode to the parent directory.
6070 int btrfs_add_link(struct btrfs_trans_handle *trans,
6071 struct btrfs_inode *parent_inode, struct btrfs_inode *inode,
6072 const char *name, int name_len, int add_backref, u64 index)
6075 struct btrfs_key key;
6076 struct btrfs_root *root = parent_inode->root;
6077 u64 ino = btrfs_ino(inode);
6078 u64 parent_ino = btrfs_ino(parent_inode);
6080 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
6081 memcpy(&key, &inode->root->root_key, sizeof(key));
6084 key.type = BTRFS_INODE_ITEM_KEY;
6088 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
6089 ret = btrfs_add_root_ref(trans, key.objectid,
6090 root->root_key.objectid, parent_ino,
6091 index, name, name_len);
6092 } else if (add_backref) {
6093 ret = btrfs_insert_inode_ref(trans, root, name, name_len, ino,
6097 /* Nothing to clean up yet */
6101 ret = btrfs_insert_dir_item(trans, name, name_len, parent_inode, &key,
6102 btrfs_inode_type(&inode->vfs_inode), index);
6103 if (ret == -EEXIST || ret == -EOVERFLOW)
6106 btrfs_abort_transaction(trans, ret);
6110 btrfs_i_size_write(parent_inode, parent_inode->vfs_inode.i_size +
6112 inode_inc_iversion(&parent_inode->vfs_inode);
6114 * If we are replaying a log tree, we do not want to update the mtime
6115 * and ctime of the parent directory with the current time, since the
6116 * log replay procedure is responsible for setting them to their correct
6117 * values (the ones it had when the fsync was done).
6119 if (!test_bit(BTRFS_FS_LOG_RECOVERING, &root->fs_info->flags)) {
6120 struct timespec64 now = current_time(&parent_inode->vfs_inode);
6122 parent_inode->vfs_inode.i_mtime = now;
6123 parent_inode->vfs_inode.i_ctime = now;
6125 ret = btrfs_update_inode(trans, root, &parent_inode->vfs_inode);
6127 btrfs_abort_transaction(trans, ret);
6131 if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
6134 err = btrfs_del_root_ref(trans, key.objectid,
6135 root->root_key.objectid, parent_ino,
6136 &local_index, name, name_len);
6138 btrfs_abort_transaction(trans, err);
6139 } else if (add_backref) {
6143 err = btrfs_del_inode_ref(trans, root, name, name_len,
6144 ino, parent_ino, &local_index);
6146 btrfs_abort_transaction(trans, err);
6149 /* Return the original error code */
6153 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
6154 struct btrfs_inode *dir, struct dentry *dentry,
6155 struct btrfs_inode *inode, int backref, u64 index)
6157 int err = btrfs_add_link(trans, dir, inode,
6158 dentry->d_name.name, dentry->d_name.len,
6165 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
6166 umode_t mode, dev_t rdev)
6168 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
6169 struct btrfs_trans_handle *trans;
6170 struct btrfs_root *root = BTRFS_I(dir)->root;
6171 struct inode *inode = NULL;
6177 * 2 for inode item and ref
6179 * 1 for xattr if selinux is on
6181 trans = btrfs_start_transaction(root, 5);
6183 return PTR_ERR(trans);
6185 err = btrfs_find_free_ino(root, &objectid);
6189 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
6190 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid,
6192 if (IS_ERR(inode)) {
6193 err = PTR_ERR(inode);
6199 * If the active LSM wants to access the inode during
6200 * d_instantiate it needs these. Smack checks to see
6201 * if the filesystem supports xattrs by looking at the
6204 inode->i_op = &btrfs_special_inode_operations;
6205 init_special_inode(inode, inode->i_mode, rdev);
6207 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
6211 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode),
6216 btrfs_update_inode(trans, root, inode);
6217 d_instantiate_new(dentry, inode);
6220 btrfs_end_transaction(trans);
6221 btrfs_btree_balance_dirty(fs_info);
6223 inode_dec_link_count(inode);
6224 discard_new_inode(inode);
6229 static int btrfs_create(struct inode *dir, struct dentry *dentry,
6230 umode_t mode, bool excl)
6232 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
6233 struct btrfs_trans_handle *trans;
6234 struct btrfs_root *root = BTRFS_I(dir)->root;
6235 struct inode *inode = NULL;
6241 * 2 for inode item and ref
6243 * 1 for xattr if selinux is on
6245 trans = btrfs_start_transaction(root, 5);
6247 return PTR_ERR(trans);
6249 err = btrfs_find_free_ino(root, &objectid);
6253 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
6254 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid,
6256 if (IS_ERR(inode)) {
6257 err = PTR_ERR(inode);
6262 * If the active LSM wants to access the inode during
6263 * d_instantiate it needs these. Smack checks to see
6264 * if the filesystem supports xattrs by looking at the
6267 inode->i_fop = &btrfs_file_operations;
6268 inode->i_op = &btrfs_file_inode_operations;
6269 inode->i_mapping->a_ops = &btrfs_aops;
6271 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
6275 err = btrfs_update_inode(trans, root, inode);
6279 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode),
6284 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
6285 d_instantiate_new(dentry, inode);
6288 btrfs_end_transaction(trans);
6290 inode_dec_link_count(inode);
6291 discard_new_inode(inode);
6293 btrfs_btree_balance_dirty(fs_info);
6297 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
6298 struct dentry *dentry)
6300 struct btrfs_trans_handle *trans = NULL;
6301 struct btrfs_root *root = BTRFS_I(dir)->root;
6302 struct inode *inode = d_inode(old_dentry);
6303 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
6308 /* do not allow sys_link's with other subvols of the same device */
6309 if (root->root_key.objectid != BTRFS_I(inode)->root->root_key.objectid)
6312 if (inode->i_nlink >= BTRFS_LINK_MAX)
6315 err = btrfs_set_inode_index(BTRFS_I(dir), &index);
6320 * 2 items for inode and inode ref
6321 * 2 items for dir items
6322 * 1 item for parent inode
6323 * 1 item for orphan item deletion if O_TMPFILE
6325 trans = btrfs_start_transaction(root, inode->i_nlink ? 5 : 6);
6326 if (IS_ERR(trans)) {
6327 err = PTR_ERR(trans);
6332 /* There are several dir indexes for this inode, clear the cache. */
6333 BTRFS_I(inode)->dir_index = 0ULL;
6335 inode_inc_iversion(inode);
6336 inode->i_ctime = current_time(inode);
6338 set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags);
6340 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry, BTRFS_I(inode),
6346 struct dentry *parent = dentry->d_parent;
6349 err = btrfs_update_inode(trans, root, inode);
6352 if (inode->i_nlink == 1) {
6354 * If new hard link count is 1, it's a file created
6355 * with open(2) O_TMPFILE flag.
6357 err = btrfs_orphan_del(trans, BTRFS_I(inode));
6361 d_instantiate(dentry, inode);
6362 ret = btrfs_log_new_name(trans, BTRFS_I(inode), NULL, parent,
6364 if (ret == BTRFS_NEED_TRANS_COMMIT) {
6365 err = btrfs_commit_transaction(trans);
6372 btrfs_end_transaction(trans);
6374 inode_dec_link_count(inode);
6377 btrfs_btree_balance_dirty(fs_info);
6381 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
6383 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
6384 struct inode *inode = NULL;
6385 struct btrfs_trans_handle *trans;
6386 struct btrfs_root *root = BTRFS_I(dir)->root;
6392 * 2 items for inode and ref
6393 * 2 items for dir items
6394 * 1 for xattr if selinux is on
6396 trans = btrfs_start_transaction(root, 5);
6398 return PTR_ERR(trans);
6400 err = btrfs_find_free_ino(root, &objectid);
6404 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
6405 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)), objectid,
6406 S_IFDIR | mode, &index);
6407 if (IS_ERR(inode)) {
6408 err = PTR_ERR(inode);
6413 /* these must be set before we unlock the inode */
6414 inode->i_op = &btrfs_dir_inode_operations;
6415 inode->i_fop = &btrfs_dir_file_operations;
6417 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
6421 btrfs_i_size_write(BTRFS_I(inode), 0);
6422 err = btrfs_update_inode(trans, root, inode);
6426 err = btrfs_add_link(trans, BTRFS_I(dir), BTRFS_I(inode),
6427 dentry->d_name.name,
6428 dentry->d_name.len, 0, index);
6432 d_instantiate_new(dentry, inode);
6435 btrfs_end_transaction(trans);
6437 inode_dec_link_count(inode);
6438 discard_new_inode(inode);
6440 btrfs_btree_balance_dirty(fs_info);
6444 static noinline int uncompress_inline(struct btrfs_path *path,
6446 size_t pg_offset, u64 extent_offset,
6447 struct btrfs_file_extent_item *item)
6450 struct extent_buffer *leaf = path->nodes[0];
6453 unsigned long inline_size;
6457 WARN_ON(pg_offset != 0);
6458 compress_type = btrfs_file_extent_compression(leaf, item);
6459 max_size = btrfs_file_extent_ram_bytes(leaf, item);
6460 inline_size = btrfs_file_extent_inline_item_len(leaf,
6461 btrfs_item_nr(path->slots[0]));
6462 tmp = kmalloc(inline_size, GFP_NOFS);
6465 ptr = btrfs_file_extent_inline_start(item);
6467 read_extent_buffer(leaf, tmp, ptr, inline_size);
6469 max_size = min_t(unsigned long, PAGE_SIZE, max_size);
6470 ret = btrfs_decompress(compress_type, tmp, page,
6471 extent_offset, inline_size, max_size);
6474 * decompression code contains a memset to fill in any space between the end
6475 * of the uncompressed data and the end of max_size in case the decompressed
6476 * data ends up shorter than ram_bytes. That doesn't cover the hole between
6477 * the end of an inline extent and the beginning of the next block, so we
6478 * cover that region here.
6481 if (max_size + pg_offset < PAGE_SIZE) {
6482 char *map = kmap(page);
6483 memset(map + pg_offset + max_size, 0, PAGE_SIZE - max_size - pg_offset);
6491 * btrfs_get_extent - Lookup the first extent overlapping a range in a file.
6492 * @inode: file to search in
6493 * @page: page to read extent data into if the extent is inline
6494 * @pg_offset: offset into @page to copy to
6495 * @start: file offset
6496 * @len: length of range starting at @start
6498 * This returns the first &struct extent_map which overlaps with the given
6499 * range, reading it from the B-tree and caching it if necessary. Note that
6500 * there may be more extents which overlap the given range after the returned
6503 * If @page is not NULL and the extent is inline, this also reads the extent
6504 * data directly into the page and marks the extent up to date in the io_tree.
6506 * Return: ERR_PTR on error, non-NULL extent_map on success.
6508 struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
6509 struct page *page, size_t pg_offset,
6512 struct btrfs_fs_info *fs_info = inode->root->fs_info;
6515 u64 extent_start = 0;
6517 u64 objectid = btrfs_ino(inode);
6518 int extent_type = -1;
6519 struct btrfs_path *path = NULL;
6520 struct btrfs_root *root = inode->root;
6521 struct btrfs_file_extent_item *item;
6522 struct extent_buffer *leaf;
6523 struct btrfs_key found_key;
6524 struct extent_map *em = NULL;
6525 struct extent_map_tree *em_tree = &inode->extent_tree;
6526 struct extent_io_tree *io_tree = &inode->io_tree;
6528 read_lock(&em_tree->lock);
6529 em = lookup_extent_mapping(em_tree, start, len);
6530 read_unlock(&em_tree->lock);
6533 if (em->start > start || em->start + em->len <= start)
6534 free_extent_map(em);
6535 else if (em->block_start == EXTENT_MAP_INLINE && page)
6536 free_extent_map(em);
6540 em = alloc_extent_map();
6545 em->start = EXTENT_MAP_HOLE;
6546 em->orig_start = EXTENT_MAP_HOLE;
6548 em->block_len = (u64)-1;
6550 path = btrfs_alloc_path();
6556 /* Chances are we'll be called again, so go ahead and do readahead */
6557 path->reada = READA_FORWARD;
6560 * Unless we're going to uncompress the inline extent, no sleep would
6563 path->leave_spinning = 1;
6565 ret = btrfs_lookup_file_extent(NULL, root, path, objectid, start, 0);
6569 } else if (ret > 0) {
6570 if (path->slots[0] == 0)
6575 leaf = path->nodes[0];
6576 item = btrfs_item_ptr(leaf, path->slots[0],
6577 struct btrfs_file_extent_item);
6578 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6579 if (found_key.objectid != objectid ||
6580 found_key.type != BTRFS_EXTENT_DATA_KEY) {
6582 * If we backup past the first extent we want to move forward
6583 * and see if there is an extent in front of us, otherwise we'll
6584 * say there is a hole for our whole search range which can
6591 extent_type = btrfs_file_extent_type(leaf, item);
6592 extent_start = found_key.offset;
6593 extent_end = btrfs_file_extent_end(path);
6594 if (extent_type == BTRFS_FILE_EXTENT_REG ||
6595 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
6596 /* Only regular file could have regular/prealloc extent */
6597 if (!S_ISREG(inode->vfs_inode.i_mode)) {
6600 "regular/prealloc extent found for non-regular inode %llu",
6604 trace_btrfs_get_extent_show_fi_regular(inode, leaf, item,
6606 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
6607 trace_btrfs_get_extent_show_fi_inline(inode, leaf, item,
6612 if (start >= extent_end) {
6614 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
6615 ret = btrfs_next_leaf(root, path);
6619 } else if (ret > 0) {
6622 leaf = path->nodes[0];
6624 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
6625 if (found_key.objectid != objectid ||
6626 found_key.type != BTRFS_EXTENT_DATA_KEY)
6628 if (start + len <= found_key.offset)
6630 if (start > found_key.offset)
6633 /* New extent overlaps with existing one */
6635 em->orig_start = start;
6636 em->len = found_key.offset - start;
6637 em->block_start = EXTENT_MAP_HOLE;
6641 btrfs_extent_item_to_extent_map(inode, path, item, !page, em);
6643 if (extent_type == BTRFS_FILE_EXTENT_REG ||
6644 extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
6646 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
6650 size_t extent_offset;
6656 size = btrfs_file_extent_ram_bytes(leaf, item);
6657 extent_offset = page_offset(page) + pg_offset - extent_start;
6658 copy_size = min_t(u64, PAGE_SIZE - pg_offset,
6659 size - extent_offset);
6660 em->start = extent_start + extent_offset;
6661 em->len = ALIGN(copy_size, fs_info->sectorsize);
6662 em->orig_block_len = em->len;
6663 em->orig_start = em->start;
6664 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
6666 btrfs_set_path_blocking(path);
6667 if (!PageUptodate(page)) {
6668 if (btrfs_file_extent_compression(leaf, item) !=
6669 BTRFS_COMPRESS_NONE) {
6670 ret = uncompress_inline(path, page, pg_offset,
6671 extent_offset, item);
6678 read_extent_buffer(leaf, map + pg_offset, ptr,
6680 if (pg_offset + copy_size < PAGE_SIZE) {
6681 memset(map + pg_offset + copy_size, 0,
6682 PAGE_SIZE - pg_offset -
6687 flush_dcache_page(page);
6689 set_extent_uptodate(io_tree, em->start,
6690 extent_map_end(em) - 1, NULL, GFP_NOFS);
6695 em->orig_start = start;
6697 em->block_start = EXTENT_MAP_HOLE;
6699 btrfs_release_path(path);
6700 if (em->start > start || extent_map_end(em) <= start) {
6702 "bad extent! em: [%llu %llu] passed [%llu %llu]",
6703 em->start, em->len, start, len);
6709 write_lock(&em_tree->lock);
6710 err = btrfs_add_extent_mapping(fs_info, em_tree, &em, start, len);
6711 write_unlock(&em_tree->lock);
6713 btrfs_free_path(path);
6715 trace_btrfs_get_extent(root, inode, em);
6718 free_extent_map(em);
6719 return ERR_PTR(err);
6721 BUG_ON(!em); /* Error is always set */
6725 struct extent_map *btrfs_get_extent_fiemap(struct btrfs_inode *inode,
6728 struct extent_map *em;
6729 struct extent_map *hole_em = NULL;
6730 u64 delalloc_start = start;
6736 em = btrfs_get_extent(inode, NULL, 0, start, len);
6740 * If our em maps to:
6742 * - a pre-alloc extent,
6743 * there might actually be delalloc bytes behind it.
6745 if (em->block_start != EXTENT_MAP_HOLE &&
6746 !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
6751 /* check to see if we've wrapped (len == -1 or similar) */
6760 /* ok, we didn't find anything, lets look for delalloc */
6761 delalloc_len = count_range_bits(&inode->io_tree, &delalloc_start,
6762 end, len, EXTENT_DELALLOC, 1);
6763 delalloc_end = delalloc_start + delalloc_len;
6764 if (delalloc_end < delalloc_start)
6765 delalloc_end = (u64)-1;
6768 * We didn't find anything useful, return the original results from
6771 if (delalloc_start > end || delalloc_end <= start) {
6778 * Adjust the delalloc_start to make sure it doesn't go backwards from
6779 * the start they passed in
6781 delalloc_start = max(start, delalloc_start);
6782 delalloc_len = delalloc_end - delalloc_start;
6784 if (delalloc_len > 0) {
6787 const u64 hole_end = extent_map_end(hole_em);
6789 em = alloc_extent_map();
6797 * When btrfs_get_extent can't find anything it returns one
6800 * Make sure what it found really fits our range, and adjust to
6801 * make sure it is based on the start from the caller
6803 if (hole_end <= start || hole_em->start > end) {
6804 free_extent_map(hole_em);
6807 hole_start = max(hole_em->start, start);
6808 hole_len = hole_end - hole_start;
6811 if (hole_em && delalloc_start > hole_start) {
6813 * Our hole starts before our delalloc, so we have to
6814 * return just the parts of the hole that go until the
6817 em->len = min(hole_len, delalloc_start - hole_start);
6818 em->start = hole_start;
6819 em->orig_start = hole_start;
6821 * Don't adjust block start at all, it is fixed at
6824 em->block_start = hole_em->block_start;
6825 em->block_len = hole_len;
6826 if (test_bit(EXTENT_FLAG_PREALLOC, &hole_em->flags))
6827 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
6830 * Hole is out of passed range or it starts after
6833 em->start = delalloc_start;
6834 em->len = delalloc_len;
6835 em->orig_start = delalloc_start;
6836 em->block_start = EXTENT_MAP_DELALLOC;
6837 em->block_len = delalloc_len;
6844 free_extent_map(hole_em);
6846 free_extent_map(em);
6847 return ERR_PTR(err);
6852 static struct extent_map *btrfs_create_dio_extent(struct inode *inode,
6855 const u64 orig_start,
6856 const u64 block_start,
6857 const u64 block_len,
6858 const u64 orig_block_len,
6859 const u64 ram_bytes,
6862 struct extent_map *em = NULL;
6865 if (type != BTRFS_ORDERED_NOCOW) {
6866 em = create_io_em(inode, start, len, orig_start,
6867 block_start, block_len, orig_block_len,
6869 BTRFS_COMPRESS_NONE, /* compress_type */
6874 ret = btrfs_add_ordered_extent_dio(inode, start, block_start,
6875 len, block_len, type);
6878 free_extent_map(em);
6879 btrfs_drop_extent_cache(BTRFS_I(inode), start,
6880 start + len - 1, 0);
6889 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
6892 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
6893 struct btrfs_root *root = BTRFS_I(inode)->root;
6894 struct extent_map *em;
6895 struct btrfs_key ins;
6899 alloc_hint = get_extent_allocation_hint(inode, start, len);
6900 ret = btrfs_reserve_extent(root, len, len, fs_info->sectorsize,
6901 0, alloc_hint, &ins, 1, 1);
6903 return ERR_PTR(ret);
6905 em = btrfs_create_dio_extent(inode, start, ins.offset, start,
6906 ins.objectid, ins.offset, ins.offset,
6907 ins.offset, BTRFS_ORDERED_REGULAR);
6908 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
6910 btrfs_free_reserved_extent(fs_info, ins.objectid,
6917 * returns 1 when the nocow is safe, < 1 on error, 0 if the
6918 * block must be cow'd
6920 noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
6921 u64 *orig_start, u64 *orig_block_len,
6924 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
6925 struct btrfs_path *path;
6927 struct extent_buffer *leaf;
6928 struct btrfs_root *root = BTRFS_I(inode)->root;
6929 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
6930 struct btrfs_file_extent_item *fi;
6931 struct btrfs_key key;
6938 bool nocow = (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW);
6940 path = btrfs_alloc_path();
6944 ret = btrfs_lookup_file_extent(NULL, root, path,
6945 btrfs_ino(BTRFS_I(inode)), offset, 0);
6949 slot = path->slots[0];
6952 /* can't find the item, must cow */
6959 leaf = path->nodes[0];
6960 btrfs_item_key_to_cpu(leaf, &key, slot);
6961 if (key.objectid != btrfs_ino(BTRFS_I(inode)) ||
6962 key.type != BTRFS_EXTENT_DATA_KEY) {
6963 /* not our file or wrong item type, must cow */
6967 if (key.offset > offset) {
6968 /* Wrong offset, must cow */
6972 fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
6973 found_type = btrfs_file_extent_type(leaf, fi);
6974 if (found_type != BTRFS_FILE_EXTENT_REG &&
6975 found_type != BTRFS_FILE_EXTENT_PREALLOC) {
6976 /* not a regular extent, must cow */
6980 if (!nocow && found_type == BTRFS_FILE_EXTENT_REG)
6983 extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
6984 if (extent_end <= offset)
6987 disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
6988 if (disk_bytenr == 0)
6991 if (btrfs_file_extent_compression(leaf, fi) ||
6992 btrfs_file_extent_encryption(leaf, fi) ||
6993 btrfs_file_extent_other_encoding(leaf, fi))
6997 * Do the same check as in btrfs_cross_ref_exist but without the
6998 * unnecessary search.
7000 if (btrfs_file_extent_generation(leaf, fi) <=
7001 btrfs_root_last_snapshot(&root->root_item))
7004 backref_offset = btrfs_file_extent_offset(leaf, fi);
7007 *orig_start = key.offset - backref_offset;
7008 *orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi);
7009 *ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi);
7012 if (btrfs_extent_readonly(fs_info, disk_bytenr))
7015 num_bytes = min(offset + *len, extent_end) - offset;
7016 if (!nocow && found_type == BTRFS_FILE_EXTENT_PREALLOC) {
7019 range_end = round_up(offset + num_bytes,
7020 root->fs_info->sectorsize) - 1;
7021 ret = test_range_bit(io_tree, offset, range_end,
7022 EXTENT_DELALLOC, 0, NULL);
7029 btrfs_release_path(path);
7032 * look for other files referencing this extent, if we
7033 * find any we must cow
7036 ret = btrfs_cross_ref_exist(root, btrfs_ino(BTRFS_I(inode)),
7037 key.offset - backref_offset, disk_bytenr);
7044 * adjust disk_bytenr and num_bytes to cover just the bytes
7045 * in this extent we are about to write. If there
7046 * are any csums in that range we have to cow in order
7047 * to keep the csums correct
7049 disk_bytenr += backref_offset;
7050 disk_bytenr += offset - key.offset;
7051 if (csum_exist_in_range(fs_info, disk_bytenr, num_bytes))
7054 * all of the above have passed, it is safe to overwrite this extent
7060 btrfs_free_path(path);
7064 static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
7065 struct extent_state **cached_state, int writing)
7067 struct btrfs_ordered_extent *ordered;
7071 lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend,
7074 * We're concerned with the entire range that we're going to be
7075 * doing DIO to, so we need to make sure there's no ordered
7076 * extents in this range.
7078 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), lockstart,
7079 lockend - lockstart + 1);
7082 * We need to make sure there are no buffered pages in this
7083 * range either, we could have raced between the invalidate in
7084 * generic_file_direct_write and locking the extent. The
7085 * invalidate needs to happen so that reads after a write do not
7089 (!writing || !filemap_range_has_page(inode->i_mapping,
7090 lockstart, lockend)))
7093 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
7098 * If we are doing a DIO read and the ordered extent we
7099 * found is for a buffered write, we can not wait for it
7100 * to complete and retry, because if we do so we can
7101 * deadlock with concurrent buffered writes on page
7102 * locks. This happens only if our DIO read covers more
7103 * than one extent map, if at this point has already
7104 * created an ordered extent for a previous extent map
7105 * and locked its range in the inode's io tree, and a
7106 * concurrent write against that previous extent map's
7107 * range and this range started (we unlock the ranges
7108 * in the io tree only when the bios complete and
7109 * buffered writes always lock pages before attempting
7110 * to lock range in the io tree).
7113 test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags))
7114 btrfs_start_ordered_extent(inode, ordered, 1);
7117 btrfs_put_ordered_extent(ordered);
7120 * We could trigger writeback for this range (and wait
7121 * for it to complete) and then invalidate the pages for
7122 * this range (through invalidate_inode_pages2_range()),
7123 * but that can lead us to a deadlock with a concurrent
7124 * call to readpages() (a buffered read or a defrag call
7125 * triggered a readahead) on a page lock due to an
7126 * ordered dio extent we created before but did not have
7127 * yet a corresponding bio submitted (whence it can not
7128 * complete), which makes readpages() wait for that
7129 * ordered extent to complete while holding a lock on
7144 /* The callers of this must take lock_extent() */
7145 static struct extent_map *create_io_em(struct inode *inode, u64 start, u64 len,
7146 u64 orig_start, u64 block_start,
7147 u64 block_len, u64 orig_block_len,
7148 u64 ram_bytes, int compress_type,
7151 struct extent_map_tree *em_tree;
7152 struct extent_map *em;
7155 ASSERT(type == BTRFS_ORDERED_PREALLOC ||
7156 type == BTRFS_ORDERED_COMPRESSED ||
7157 type == BTRFS_ORDERED_NOCOW ||
7158 type == BTRFS_ORDERED_REGULAR);
7160 em_tree = &BTRFS_I(inode)->extent_tree;
7161 em = alloc_extent_map();
7163 return ERR_PTR(-ENOMEM);
7166 em->orig_start = orig_start;
7168 em->block_len = block_len;
7169 em->block_start = block_start;
7170 em->orig_block_len = orig_block_len;
7171 em->ram_bytes = ram_bytes;
7172 em->generation = -1;
7173 set_bit(EXTENT_FLAG_PINNED, &em->flags);
7174 if (type == BTRFS_ORDERED_PREALLOC) {
7175 set_bit(EXTENT_FLAG_FILLING, &em->flags);
7176 } else if (type == BTRFS_ORDERED_COMPRESSED) {
7177 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
7178 em->compress_type = compress_type;
7182 btrfs_drop_extent_cache(BTRFS_I(inode), em->start,
7183 em->start + em->len - 1, 0);
7184 write_lock(&em_tree->lock);
7185 ret = add_extent_mapping(em_tree, em, 1);
7186 write_unlock(&em_tree->lock);
7188 * The caller has taken lock_extent(), who could race with us
7191 } while (ret == -EEXIST);
7194 free_extent_map(em);
7195 return ERR_PTR(ret);
7198 /* em got 2 refs now, callers needs to do free_extent_map once. */
7203 static int btrfs_get_blocks_direct_read(struct extent_map *em,
7204 struct buffer_head *bh_result,
7205 struct inode *inode,
7208 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7210 if (em->block_start == EXTENT_MAP_HOLE ||
7211 test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
7214 len = min(len, em->len - (start - em->start));
7216 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
7218 bh_result->b_size = len;
7219 bh_result->b_bdev = fs_info->fs_devices->latest_bdev;
7220 set_buffer_mapped(bh_result);
7225 static int btrfs_get_blocks_direct_write(struct extent_map **map,
7226 struct buffer_head *bh_result,
7227 struct inode *inode,
7228 struct btrfs_dio_data *dio_data,
7231 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7232 struct extent_map *em = *map;
7236 * We don't allocate a new extent in the following cases
7238 * 1) The inode is marked as NODATACOW. In this case we'll just use the
7240 * 2) The extent is marked as PREALLOC. We're good to go here and can
7241 * just use the extent.
7244 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
7245 ((BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) &&
7246 em->block_start != EXTENT_MAP_HOLE)) {
7248 u64 block_start, orig_start, orig_block_len, ram_bytes;
7250 if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
7251 type = BTRFS_ORDERED_PREALLOC;
7253 type = BTRFS_ORDERED_NOCOW;
7254 len = min(len, em->len - (start - em->start));
7255 block_start = em->block_start + (start - em->start);
7257 if (can_nocow_extent(inode, start, &len, &orig_start,
7258 &orig_block_len, &ram_bytes) == 1 &&
7259 btrfs_inc_nocow_writers(fs_info, block_start)) {
7260 struct extent_map *em2;
7262 em2 = btrfs_create_dio_extent(inode, start, len,
7263 orig_start, block_start,
7264 len, orig_block_len,
7266 btrfs_dec_nocow_writers(fs_info, block_start);
7267 if (type == BTRFS_ORDERED_PREALLOC) {
7268 free_extent_map(em);
7272 if (em2 && IS_ERR(em2)) {
7277 * For inode marked NODATACOW or extent marked PREALLOC,
7278 * use the existing or preallocated extent, so does not
7279 * need to adjust btrfs_space_info's bytes_may_use.
7281 btrfs_free_reserved_data_space_noquota(inode, start,
7287 /* this will cow the extent */
7288 len = bh_result->b_size;
7289 free_extent_map(em);
7290 *map = em = btrfs_new_extent_direct(inode, start, len);
7296 len = min(len, em->len - (start - em->start));
7299 bh_result->b_blocknr = (em->block_start + (start - em->start)) >>
7301 bh_result->b_size = len;
7302 bh_result->b_bdev = fs_info->fs_devices->latest_bdev;
7303 set_buffer_mapped(bh_result);
7305 if (!test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
7306 set_buffer_new(bh_result);
7309 * Need to update the i_size under the extent lock so buffered
7310 * readers will get the updated i_size when we unlock.
7312 if (!dio_data->overwrite && start + len > i_size_read(inode))
7313 i_size_write(inode, start + len);
7315 WARN_ON(dio_data->reserve < len);
7316 dio_data->reserve -= len;
7317 dio_data->unsubmitted_oe_range_end = start + len;
7318 current->journal_info = dio_data;
7323 static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
7324 struct buffer_head *bh_result, int create)
7326 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7327 struct extent_map *em;
7328 struct extent_state *cached_state = NULL;
7329 struct btrfs_dio_data *dio_data = NULL;
7330 u64 start = iblock << inode->i_blkbits;
7331 u64 lockstart, lockend;
7332 u64 len = bh_result->b_size;
7336 len = min_t(u64, len, fs_info->sectorsize);
7339 lockend = start + len - 1;
7341 if (current->journal_info) {
7343 * Need to pull our outstanding extents and set journal_info to NULL so
7344 * that anything that needs to check if there's a transaction doesn't get
7347 dio_data = current->journal_info;
7348 current->journal_info = NULL;
7352 * If this errors out it's because we couldn't invalidate pagecache for
7353 * this range and we need to fallback to buffered.
7355 if (lock_extent_direct(inode, lockstart, lockend, &cached_state,
7361 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len);
7368 * Ok for INLINE and COMPRESSED extents we need to fallback on buffered
7369 * io. INLINE is special, and we could probably kludge it in here, but
7370 * it's still buffered so for safety lets just fall back to the generic
7373 * For COMPRESSED we _have_ to read the entire extent in so we can
7374 * decompress it, so there will be buffering required no matter what we
7375 * do, so go ahead and fallback to buffered.
7377 * We return -ENOTBLK because that's what makes DIO go ahead and go back
7378 * to buffered IO. Don't blame me, this is the price we pay for using
7381 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags) ||
7382 em->block_start == EXTENT_MAP_INLINE) {
7383 free_extent_map(em);
7389 ret = btrfs_get_blocks_direct_write(&em, bh_result, inode,
7390 dio_data, start, len);
7394 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart,
7395 lockend, &cached_state);
7397 ret = btrfs_get_blocks_direct_read(em, bh_result, inode,
7399 /* Can be negative only if we read from a hole */
7402 free_extent_map(em);
7406 * We need to unlock only the end area that we aren't using.
7407 * The rest is going to be unlocked by the endio routine.
7409 lockstart = start + bh_result->b_size;
7410 if (lockstart < lockend) {
7411 unlock_extent_cached(&BTRFS_I(inode)->io_tree,
7412 lockstart, lockend, &cached_state);
7414 free_extent_state(cached_state);
7418 free_extent_map(em);
7423 unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
7427 current->journal_info = dio_data;
7431 static void btrfs_dio_private_put(struct btrfs_dio_private *dip)
7434 * This implies a barrier so that stores to dio_bio->bi_status before
7435 * this and loads of dio_bio->bi_status after this are fully ordered.
7437 if (!refcount_dec_and_test(&dip->refs))
7440 if (bio_op(dip->dio_bio) == REQ_OP_WRITE) {
7441 __endio_write_update_ordered(dip->inode, dip->logical_offset,
7443 !dip->dio_bio->bi_status);
7445 unlock_extent(&BTRFS_I(dip->inode)->io_tree,
7446 dip->logical_offset,
7447 dip->logical_offset + dip->bytes - 1);
7450 dio_end_io(dip->dio_bio);
7454 static blk_status_t submit_dio_repair_bio(struct inode *inode, struct bio *bio,
7456 unsigned long bio_flags)
7458 struct btrfs_dio_private *dip = bio->bi_private;
7459 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7462 BUG_ON(bio_op(bio) == REQ_OP_WRITE);
7464 ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DATA);
7468 refcount_inc(&dip->refs);
7469 ret = btrfs_map_bio(fs_info, bio, mirror_num);
7471 refcount_dec(&dip->refs);
7475 static blk_status_t btrfs_check_read_dio_bio(struct inode *inode,
7476 struct btrfs_io_bio *io_bio,
7477 const bool uptodate)
7479 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
7480 const u32 sectorsize = fs_info->sectorsize;
7481 struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
7482 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
7483 const bool csum = !(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM);
7484 struct bio_vec bvec;
7485 struct bvec_iter iter;
7486 u64 start = io_bio->logical;
7488 blk_status_t err = BLK_STS_OK;
7490 __bio_for_each_segment(bvec, &io_bio->bio, iter, io_bio->iter) {
7491 unsigned int i, nr_sectors, pgoff;
7493 nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec.bv_len);
7494 pgoff = bvec.bv_offset;
7495 for (i = 0; i < nr_sectors; i++) {
7496 ASSERT(pgoff < PAGE_SIZE);
7498 (!csum || !check_data_csum(inode, io_bio, icsum,
7499 bvec.bv_page, pgoff,
7500 start, sectorsize))) {
7501 clean_io_failure(fs_info, failure_tree, io_tree,
7502 start, bvec.bv_page,
7503 btrfs_ino(BTRFS_I(inode)),
7506 blk_status_t status;
7508 status = btrfs_submit_read_repair(inode,
7510 start - io_bio->logical,
7511 bvec.bv_page, pgoff,
7513 start + sectorsize - 1,
7515 submit_dio_repair_bio);
7519 start += sectorsize;
7521 pgoff += sectorsize;
7527 static void __endio_write_update_ordered(struct inode *inode,
7528 const u64 offset, const u64 bytes,
7529 const bool uptodate)
7531 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7532 struct btrfs_ordered_extent *ordered = NULL;
7533 struct btrfs_workqueue *wq;
7534 u64 ordered_offset = offset;
7535 u64 ordered_bytes = bytes;
7538 if (btrfs_is_free_space_inode(BTRFS_I(inode)))
7539 wq = fs_info->endio_freespace_worker;
7541 wq = fs_info->endio_write_workers;
7543 while (ordered_offset < offset + bytes) {
7544 last_offset = ordered_offset;
7545 if (btrfs_dec_test_first_ordered_pending(inode, &ordered,
7549 btrfs_init_work(&ordered->work, finish_ordered_fn, NULL,
7551 btrfs_queue_work(wq, &ordered->work);
7554 * If btrfs_dec_test_ordered_pending does not find any ordered
7555 * extent in the range, we can exit.
7557 if (ordered_offset == last_offset)
7560 * Our bio might span multiple ordered extents. In this case
7561 * we keep going until we have accounted the whole dio.
7563 if (ordered_offset < offset + bytes) {
7564 ordered_bytes = offset + bytes - ordered_offset;
7570 static blk_status_t btrfs_submit_bio_start_direct_io(void *private_data,
7571 struct bio *bio, u64 offset)
7573 struct inode *inode = private_data;
7575 ret = btrfs_csum_one_bio(inode, bio, offset, 1);
7576 BUG_ON(ret); /* -ENOMEM */
7580 static void btrfs_end_dio_bio(struct bio *bio)
7582 struct btrfs_dio_private *dip = bio->bi_private;
7583 blk_status_t err = bio->bi_status;
7586 btrfs_warn(BTRFS_I(dip->inode)->root->fs_info,
7587 "direct IO failed ino %llu rw %d,%u sector %#Lx len %u err no %d",
7588 btrfs_ino(BTRFS_I(dip->inode)), bio_op(bio),
7590 (unsigned long long)bio->bi_iter.bi_sector,
7591 bio->bi_iter.bi_size, err);
7593 if (bio_op(bio) == REQ_OP_READ) {
7594 err = btrfs_check_read_dio_bio(dip->inode, btrfs_io_bio(bio),
7599 dip->dio_bio->bi_status = err;
7602 btrfs_dio_private_put(dip);
7605 static inline blk_status_t btrfs_submit_dio_bio(struct bio *bio,
7606 struct inode *inode, u64 file_offset, int async_submit)
7608 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7609 struct btrfs_dio_private *dip = bio->bi_private;
7610 bool write = bio_op(bio) == REQ_OP_WRITE;
7613 /* Check btrfs_submit_bio_hook() for rules about async submit. */
7615 async_submit = !atomic_read(&BTRFS_I(inode)->sync_writers);
7618 ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DATA);
7623 if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
7626 if (write && async_submit) {
7627 ret = btrfs_wq_submit_bio(fs_info, bio, 0, 0,
7629 btrfs_submit_bio_start_direct_io);
7633 * If we aren't doing async submit, calculate the csum of the
7636 ret = btrfs_csum_one_bio(inode, bio, file_offset, 1);
7642 csum_offset = file_offset - dip->logical_offset;
7643 csum_offset >>= inode->i_sb->s_blocksize_bits;
7644 csum_offset *= btrfs_super_csum_size(fs_info->super_copy);
7645 btrfs_io_bio(bio)->csum = dip->csums + csum_offset;
7648 ret = btrfs_map_bio(fs_info, bio, 0);
7654 * If this succeeds, the btrfs_dio_private is responsible for cleaning up locked
7655 * or ordered extents whether or not we submit any bios.
7657 static struct btrfs_dio_private *btrfs_create_dio_private(struct bio *dio_bio,
7658 struct inode *inode,
7661 const bool write = (bio_op(dio_bio) == REQ_OP_WRITE);
7662 const bool csum = !(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM);
7664 struct btrfs_dio_private *dip;
7666 dip_size = sizeof(*dip);
7667 if (!write && csum) {
7668 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7669 const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
7672 nblocks = dio_bio->bi_iter.bi_size >> inode->i_sb->s_blocksize_bits;
7673 dip_size += csum_size * nblocks;
7676 dip = kzalloc(dip_size, GFP_NOFS);
7681 dip->logical_offset = file_offset;
7682 dip->bytes = dio_bio->bi_iter.bi_size;
7683 dip->disk_bytenr = (u64)dio_bio->bi_iter.bi_sector << 9;
7684 dip->dio_bio = dio_bio;
7685 refcount_set(&dip->refs, 1);
7688 struct btrfs_dio_data *dio_data = current->journal_info;
7691 * Setting range start and end to the same value means that
7692 * no cleanup will happen in btrfs_direct_IO
7694 dio_data->unsubmitted_oe_range_end = dip->logical_offset +
7696 dio_data->unsubmitted_oe_range_start =
7697 dio_data->unsubmitted_oe_range_end;
7702 static void btrfs_submit_direct(struct bio *dio_bio, struct inode *inode,
7705 const bool write = (bio_op(dio_bio) == REQ_OP_WRITE);
7706 const bool csum = !(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM);
7707 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7708 const bool raid56 = (btrfs_data_alloc_profile(fs_info) &
7709 BTRFS_BLOCK_GROUP_RAID56_MASK);
7710 struct btrfs_dio_private *dip;
7713 int async_submit = 0;
7715 int clone_offset = 0;
7718 blk_status_t status;
7719 struct btrfs_io_geometry geom;
7721 dip = btrfs_create_dio_private(dio_bio, inode, file_offset);
7724 unlock_extent(&BTRFS_I(inode)->io_tree, file_offset,
7725 file_offset + dio_bio->bi_iter.bi_size - 1);
7727 dio_bio->bi_status = BLK_STS_RESOURCE;
7728 dio_end_io(dio_bio);
7732 if (!write && csum) {
7734 * Load the csums up front to reduce csum tree searches and
7735 * contention when submitting bios.
7737 status = btrfs_lookup_bio_sums(inode, dio_bio, file_offset,
7739 if (status != BLK_STS_OK)
7743 start_sector = dio_bio->bi_iter.bi_sector;
7744 submit_len = dio_bio->bi_iter.bi_size;
7747 ret = btrfs_get_io_geometry(fs_info, btrfs_op(dio_bio),
7748 start_sector << 9, submit_len,
7751 status = errno_to_blk_status(ret);
7754 ASSERT(geom.len <= INT_MAX);
7756 clone_len = min_t(int, submit_len, geom.len);
7759 * This will never fail as it's passing GPF_NOFS and
7760 * the allocation is backed by btrfs_bioset.
7762 bio = btrfs_bio_clone_partial(dio_bio, clone_offset, clone_len);
7763 bio->bi_private = dip;
7764 bio->bi_end_io = btrfs_end_dio_bio;
7765 btrfs_io_bio(bio)->logical = file_offset;
7767 ASSERT(submit_len >= clone_len);
7768 submit_len -= clone_len;
7771 * Increase the count before we submit the bio so we know
7772 * the end IO handler won't happen before we increase the
7773 * count. Otherwise, the dip might get freed before we're
7774 * done setting it up.
7776 * We transfer the initial reference to the last bio, so we
7777 * don't need to increment the reference count for the last one.
7779 if (submit_len > 0) {
7780 refcount_inc(&dip->refs);
7782 * If we are submitting more than one bio, submit them
7783 * all asynchronously. The exception is RAID 5 or 6, as
7784 * asynchronous checksums make it difficult to collect
7785 * full stripe writes.
7791 status = btrfs_submit_dio_bio(bio, inode, file_offset,
7796 refcount_dec(&dip->refs);
7800 clone_offset += clone_len;
7801 start_sector += clone_len >> 9;
7802 file_offset += clone_len;
7803 } while (submit_len > 0);
7807 dip->dio_bio->bi_status = status;
7808 btrfs_dio_private_put(dip);
7811 static ssize_t check_direct_IO(struct btrfs_fs_info *fs_info,
7812 const struct iov_iter *iter, loff_t offset)
7816 unsigned int blocksize_mask = fs_info->sectorsize - 1;
7817 ssize_t retval = -EINVAL;
7819 if (offset & blocksize_mask)
7822 if (iov_iter_alignment(iter) & blocksize_mask)
7825 /* If this is a write we don't need to check anymore */
7826 if (iov_iter_rw(iter) != READ || !iter_is_iovec(iter))
7829 * Check to make sure we don't have duplicate iov_base's in this
7830 * iovec, if so return EINVAL, otherwise we'll get csum errors
7831 * when reading back.
7833 for (seg = 0; seg < iter->nr_segs; seg++) {
7834 for (i = seg + 1; i < iter->nr_segs; i++) {
7835 if (iter->iov[seg].iov_base == iter->iov[i].iov_base)
7844 static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
7846 struct file *file = iocb->ki_filp;
7847 struct inode *inode = file->f_mapping->host;
7848 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
7849 struct btrfs_dio_data dio_data = { 0 };
7850 struct extent_changeset *data_reserved = NULL;
7851 loff_t offset = iocb->ki_pos;
7855 bool relock = false;
7858 if (check_direct_IO(fs_info, iter, offset))
7861 inode_dio_begin(inode);
7864 * The generic stuff only does filemap_write_and_wait_range, which
7865 * isn't enough if we've written compressed pages to this area, so
7866 * we need to flush the dirty pages again to make absolutely sure
7867 * that any outstanding dirty pages are on disk.
7869 count = iov_iter_count(iter);
7870 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
7871 &BTRFS_I(inode)->runtime_flags))
7872 filemap_fdatawrite_range(inode->i_mapping, offset,
7873 offset + count - 1);
7875 if (iov_iter_rw(iter) == WRITE) {
7877 * If the write DIO is beyond the EOF, we need update
7878 * the isize, but it is protected by i_mutex. So we can
7879 * not unlock the i_mutex at this case.
7881 if (offset + count <= inode->i_size) {
7882 dio_data.overwrite = 1;
7883 inode_unlock(inode);
7885 } else if (iocb->ki_flags & IOCB_NOWAIT) {
7889 ret = btrfs_delalloc_reserve_space(inode, &data_reserved,
7895 * We need to know how many extents we reserved so that we can
7896 * do the accounting properly if we go over the number we
7897 * originally calculated. Abuse current->journal_info for this.
7899 dio_data.reserve = round_up(count,
7900 fs_info->sectorsize);
7901 dio_data.unsubmitted_oe_range_start = (u64)offset;
7902 dio_data.unsubmitted_oe_range_end = (u64)offset;
7903 current->journal_info = &dio_data;
7904 down_read(&BTRFS_I(inode)->dio_sem);
7905 } else if (test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
7906 &BTRFS_I(inode)->runtime_flags)) {
7907 inode_dio_end(inode);
7908 flags = DIO_LOCKING | DIO_SKIP_HOLES;
7912 ret = __blockdev_direct_IO(iocb, inode,
7913 fs_info->fs_devices->latest_bdev,
7914 iter, btrfs_get_blocks_direct, NULL,
7915 btrfs_submit_direct, flags);
7916 if (iov_iter_rw(iter) == WRITE) {
7917 up_read(&BTRFS_I(inode)->dio_sem);
7918 current->journal_info = NULL;
7919 if (ret < 0 && ret != -EIOCBQUEUED) {
7920 if (dio_data.reserve)
7921 btrfs_delalloc_release_space(inode, data_reserved,
7922 offset, dio_data.reserve, true);
7924 * On error we might have left some ordered extents
7925 * without submitting corresponding bios for them, so
7926 * cleanup them up to avoid other tasks getting them
7927 * and waiting for them to complete forever.
7929 if (dio_data.unsubmitted_oe_range_start <
7930 dio_data.unsubmitted_oe_range_end)
7931 __endio_write_update_ordered(inode,
7932 dio_data.unsubmitted_oe_range_start,
7933 dio_data.unsubmitted_oe_range_end -
7934 dio_data.unsubmitted_oe_range_start,
7936 } else if (ret >= 0 && (size_t)ret < count)
7937 btrfs_delalloc_release_space(inode, data_reserved,
7938 offset, count - (size_t)ret, true);
7939 btrfs_delalloc_release_extents(BTRFS_I(inode), count);
7943 inode_dio_end(inode);
7947 extent_changeset_free(data_reserved);
7951 #define BTRFS_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC)
7953 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
7954 __u64 start, __u64 len)
7958 ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS);
7962 return extent_fiemap(inode, fieinfo, start, len);
7965 int btrfs_readpage(struct file *file, struct page *page)
7967 return extent_read_full_page(page, btrfs_get_extent, 0);
7970 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
7972 struct inode *inode = page->mapping->host;
7975 if (current->flags & PF_MEMALLOC) {
7976 redirty_page_for_writepage(wbc, page);
7982 * If we are under memory pressure we will call this directly from the
7983 * VM, we need to make sure we have the inode referenced for the ordered
7984 * extent. If not just return like we didn't do anything.
7986 if (!igrab(inode)) {
7987 redirty_page_for_writepage(wbc, page);
7988 return AOP_WRITEPAGE_ACTIVATE;
7990 ret = extent_write_full_page(page, wbc);
7991 btrfs_add_delayed_iput(inode);
7995 static int btrfs_writepages(struct address_space *mapping,
7996 struct writeback_control *wbc)
7998 return extent_writepages(mapping, wbc);
8002 btrfs_readpages(struct file *file, struct address_space *mapping,
8003 struct list_head *pages, unsigned nr_pages)
8005 return extent_readpages(mapping, pages, nr_pages);
8008 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
8010 int ret = try_release_extent_mapping(page, gfp_flags);
8012 ClearPagePrivate(page);
8013 set_page_private(page, 0);
8019 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
8021 if (PageWriteback(page) || PageDirty(page))
8023 return __btrfs_releasepage(page, gfp_flags);
8026 #ifdef CONFIG_MIGRATION
8027 static int btrfs_migratepage(struct address_space *mapping,
8028 struct page *newpage, struct page *page,
8029 enum migrate_mode mode)
8033 ret = migrate_page_move_mapping(mapping, newpage, page, 0);
8034 if (ret != MIGRATEPAGE_SUCCESS)
8037 if (page_has_private(page)) {
8038 ClearPagePrivate(page);
8040 set_page_private(newpage, page_private(page));
8041 set_page_private(page, 0);
8043 SetPagePrivate(newpage);
8046 if (PagePrivate2(page)) {
8047 ClearPagePrivate2(page);
8048 SetPagePrivate2(newpage);
8051 if (mode != MIGRATE_SYNC_NO_COPY)
8052 migrate_page_copy(newpage, page);
8054 migrate_page_states(newpage, page);
8055 return MIGRATEPAGE_SUCCESS;
8059 static void btrfs_invalidatepage(struct page *page, unsigned int offset,
8060 unsigned int length)
8062 struct inode *inode = page->mapping->host;
8063 struct extent_io_tree *tree;
8064 struct btrfs_ordered_extent *ordered;
8065 struct extent_state *cached_state = NULL;
8066 u64 page_start = page_offset(page);
8067 u64 page_end = page_start + PAGE_SIZE - 1;
8070 int inode_evicting = inode->i_state & I_FREEING;
8073 * we have the page locked, so new writeback can't start,
8074 * and the dirty bit won't be cleared while we are here.
8076 * Wait for IO on this page so that we can safely clear
8077 * the PagePrivate2 bit and do ordered accounting
8079 wait_on_page_writeback(page);
8081 tree = &BTRFS_I(inode)->io_tree;
8083 btrfs_releasepage(page, GFP_NOFS);
8087 if (!inode_evicting)
8088 lock_extent_bits(tree, page_start, page_end, &cached_state);
8091 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), start,
8092 page_end - start + 1);
8095 ordered->file_offset + ordered->num_bytes - 1);
8097 * IO on this page will never be started, so we need
8098 * to account for any ordered extents now
8100 if (!inode_evicting)
8101 clear_extent_bit(tree, start, end,
8102 EXTENT_DELALLOC | EXTENT_DELALLOC_NEW |
8103 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING |
8104 EXTENT_DEFRAG, 1, 0, &cached_state);
8106 * whoever cleared the private bit is responsible
8107 * for the finish_ordered_io
8109 if (TestClearPagePrivate2(page)) {
8110 struct btrfs_ordered_inode_tree *tree;
8113 tree = &BTRFS_I(inode)->ordered_tree;
8115 spin_lock_irq(&tree->lock);
8116 set_bit(BTRFS_ORDERED_TRUNCATED, &ordered->flags);
8117 new_len = start - ordered->file_offset;
8118 if (new_len < ordered->truncated_len)
8119 ordered->truncated_len = new_len;
8120 spin_unlock_irq(&tree->lock);
8122 if (btrfs_dec_test_ordered_pending(inode, &ordered,
8124 end - start + 1, 1))
8125 btrfs_finish_ordered_io(ordered);
8127 btrfs_put_ordered_extent(ordered);
8128 if (!inode_evicting) {
8129 cached_state = NULL;
8130 lock_extent_bits(tree, start, end,
8135 if (start < page_end)
8140 * Qgroup reserved space handler
8141 * Page here will be either
8142 * 1) Already written to disk
8143 * In this case, its reserved space is released from data rsv map
8144 * and will be freed by delayed_ref handler finally.
8145 * So even we call qgroup_free_data(), it won't decrease reserved
8147 * 2) Not written to disk
8148 * This means the reserved space should be freed here. However,
8149 * if a truncate invalidates the page (by clearing PageDirty)
8150 * and the page is accounted for while allocating extent
8151 * in btrfs_check_data_free_space() we let delayed_ref to
8152 * free the entire extent.
8154 if (PageDirty(page))
8155 btrfs_qgroup_free_data(inode, NULL, page_start, PAGE_SIZE);
8156 if (!inode_evicting) {
8157 clear_extent_bit(tree, page_start, page_end, EXTENT_LOCKED |
8158 EXTENT_DELALLOC | EXTENT_DELALLOC_NEW |
8159 EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 1, 1,
8162 __btrfs_releasepage(page, GFP_NOFS);
8165 ClearPageChecked(page);
8166 if (PagePrivate(page)) {
8167 ClearPagePrivate(page);
8168 set_page_private(page, 0);
8174 * btrfs_page_mkwrite() is not allowed to change the file size as it gets
8175 * called from a page fault handler when a page is first dirtied. Hence we must
8176 * be careful to check for EOF conditions here. We set the page up correctly
8177 * for a written page which means we get ENOSPC checking when writing into
8178 * holes and correct delalloc and unwritten extent mapping on filesystems that
8179 * support these features.
8181 * We are not allowed to take the i_mutex here so we have to play games to
8182 * protect against truncate races as the page could now be beyond EOF. Because
8183 * truncate_setsize() writes the inode size before removing pages, once we have
8184 * the page lock we can determine safely if the page is beyond EOF. If it is not
8185 * beyond EOF, then the page is guaranteed safe against truncation until we
8188 vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf)
8190 struct page *page = vmf->page;
8191 struct inode *inode = file_inode(vmf->vma->vm_file);
8192 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8193 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
8194 struct btrfs_ordered_extent *ordered;
8195 struct extent_state *cached_state = NULL;
8196 struct extent_changeset *data_reserved = NULL;
8198 unsigned long zero_start;
8208 reserved_space = PAGE_SIZE;
8210 sb_start_pagefault(inode->i_sb);
8211 page_start = page_offset(page);
8212 page_end = page_start + PAGE_SIZE - 1;
8216 * Reserving delalloc space after obtaining the page lock can lead to
8217 * deadlock. For example, if a dirty page is locked by this function
8218 * and the call to btrfs_delalloc_reserve_space() ends up triggering
8219 * dirty page write out, then the btrfs_writepage() function could
8220 * end up waiting indefinitely to get a lock on the page currently
8221 * being processed by btrfs_page_mkwrite() function.
8223 ret2 = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start,
8226 ret2 = file_update_time(vmf->vma->vm_file);
8230 ret = vmf_error(ret2);
8236 ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
8239 size = i_size_read(inode);
8241 if ((page->mapping != inode->i_mapping) ||
8242 (page_start >= size)) {
8243 /* page got truncated out from underneath us */
8246 wait_on_page_writeback(page);
8248 lock_extent_bits(io_tree, page_start, page_end, &cached_state);
8249 set_page_extent_mapped(page);
8252 * we can't set the delalloc bits if there are pending ordered
8253 * extents. Drop our locks and wait for them to finish
8255 ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), page_start,
8258 unlock_extent_cached(io_tree, page_start, page_end,
8261 btrfs_start_ordered_extent(inode, ordered, 1);
8262 btrfs_put_ordered_extent(ordered);
8266 if (page->index == ((size - 1) >> PAGE_SHIFT)) {
8267 reserved_space = round_up(size - page_start,
8268 fs_info->sectorsize);
8269 if (reserved_space < PAGE_SIZE) {
8270 end = page_start + reserved_space - 1;
8271 btrfs_delalloc_release_space(inode, data_reserved,
8272 page_start, PAGE_SIZE - reserved_space,
8278 * page_mkwrite gets called when the page is firstly dirtied after it's
8279 * faulted in, but write(2) could also dirty a page and set delalloc
8280 * bits, thus in this case for space account reason, we still need to
8281 * clear any delalloc bits within this page range since we have to
8282 * reserve data&meta space before lock_page() (see above comments).
8284 clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, end,
8285 EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |
8286 EXTENT_DEFRAG, 0, 0, &cached_state);
8288 ret2 = btrfs_set_extent_delalloc(inode, page_start, end, 0,
8291 unlock_extent_cached(io_tree, page_start, page_end,
8293 ret = VM_FAULT_SIGBUS;
8297 /* page is wholly or partially inside EOF */
8298 if (page_start + PAGE_SIZE > size)
8299 zero_start = offset_in_page(size);
8301 zero_start = PAGE_SIZE;
8303 if (zero_start != PAGE_SIZE) {
8305 memset(kaddr + zero_start, 0, PAGE_SIZE - zero_start);
8306 flush_dcache_page(page);
8309 ClearPageChecked(page);
8310 set_page_dirty(page);
8311 SetPageUptodate(page);
8313 BTRFS_I(inode)->last_trans = fs_info->generation;
8314 BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
8315 BTRFS_I(inode)->last_log_commit = BTRFS_I(inode)->root->last_log_commit;
8317 unlock_extent_cached(io_tree, page_start, page_end, &cached_state);
8319 btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE);
8320 sb_end_pagefault(inode->i_sb);
8321 extent_changeset_free(data_reserved);
8322 return VM_FAULT_LOCKED;
8327 btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE);
8328 btrfs_delalloc_release_space(inode, data_reserved, page_start,
8329 reserved_space, (ret != 0));
8331 sb_end_pagefault(inode->i_sb);
8332 extent_changeset_free(data_reserved);
8336 static int btrfs_truncate(struct inode *inode, bool skip_writeback)
8338 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8339 struct btrfs_root *root = BTRFS_I(inode)->root;
8340 struct btrfs_block_rsv *rsv;
8342 struct btrfs_trans_handle *trans;
8343 u64 mask = fs_info->sectorsize - 1;
8344 u64 min_size = btrfs_calc_metadata_size(fs_info, 1);
8346 if (!skip_writeback) {
8347 ret = btrfs_wait_ordered_range(inode, inode->i_size & (~mask),
8354 * Yes ladies and gentlemen, this is indeed ugly. We have a couple of
8355 * things going on here:
8357 * 1) We need to reserve space to update our inode.
8359 * 2) We need to have something to cache all the space that is going to
8360 * be free'd up by the truncate operation, but also have some slack
8361 * space reserved in case it uses space during the truncate (thank you
8362 * very much snapshotting).
8364 * And we need these to be separate. The fact is we can use a lot of
8365 * space doing the truncate, and we have no earthly idea how much space
8366 * we will use, so we need the truncate reservation to be separate so it
8367 * doesn't end up using space reserved for updating the inode. We also
8368 * need to be able to stop the transaction and start a new one, which
8369 * means we need to be able to update the inode several times, and we
8370 * have no idea of knowing how many times that will be, so we can't just
8371 * reserve 1 item for the entirety of the operation, so that has to be
8372 * done separately as well.
8374 * So that leaves us with
8376 * 1) rsv - for the truncate reservation, which we will steal from the
8377 * transaction reservation.
8378 * 2) fs_info->trans_block_rsv - this will have 1 items worth left for
8379 * updating the inode.
8381 rsv = btrfs_alloc_block_rsv(fs_info, BTRFS_BLOCK_RSV_TEMP);
8384 rsv->size = min_size;
8388 * 1 for the truncate slack space
8389 * 1 for updating the inode.
8391 trans = btrfs_start_transaction(root, 2);
8392 if (IS_ERR(trans)) {
8393 ret = PTR_ERR(trans);
8397 /* Migrate the slack space for the truncate to our reserve */
8398 ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv, rsv,
8403 * So if we truncate and then write and fsync we normally would just
8404 * write the extents that changed, which is a problem if we need to
8405 * first truncate that entire inode. So set this flag so we write out
8406 * all of the extents in the inode to the sync log so we're completely
8409 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags);
8410 trans->block_rsv = rsv;
8413 ret = btrfs_truncate_inode_items(trans, root, inode,
8415 BTRFS_EXTENT_DATA_KEY);
8416 trans->block_rsv = &fs_info->trans_block_rsv;
8417 if (ret != -ENOSPC && ret != -EAGAIN)
8420 ret = btrfs_update_inode(trans, root, inode);
8424 btrfs_end_transaction(trans);
8425 btrfs_btree_balance_dirty(fs_info);
8427 trans = btrfs_start_transaction(root, 2);
8428 if (IS_ERR(trans)) {
8429 ret = PTR_ERR(trans);
8434 btrfs_block_rsv_release(fs_info, rsv, -1, NULL);
8435 ret = btrfs_block_rsv_migrate(&fs_info->trans_block_rsv,
8436 rsv, min_size, false);
8437 BUG_ON(ret); /* shouldn't happen */
8438 trans->block_rsv = rsv;
8442 * We can't call btrfs_truncate_block inside a trans handle as we could
8443 * deadlock with freeze, if we got NEED_TRUNCATE_BLOCK then we know
8444 * we've truncated everything except the last little bit, and can do
8445 * btrfs_truncate_block and then update the disk_i_size.
8447 if (ret == NEED_TRUNCATE_BLOCK) {
8448 btrfs_end_transaction(trans);
8449 btrfs_btree_balance_dirty(fs_info);
8451 ret = btrfs_truncate_block(inode, inode->i_size, 0, 0);
8454 trans = btrfs_start_transaction(root, 1);
8455 if (IS_ERR(trans)) {
8456 ret = PTR_ERR(trans);
8459 btrfs_inode_safe_disk_i_size_write(inode, 0);
8465 trans->block_rsv = &fs_info->trans_block_rsv;
8466 ret2 = btrfs_update_inode(trans, root, inode);
8470 ret2 = btrfs_end_transaction(trans);
8473 btrfs_btree_balance_dirty(fs_info);
8476 btrfs_free_block_rsv(fs_info, rsv);
8482 * create a new subvolume directory/inode (helper for the ioctl).
8484 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
8485 struct btrfs_root *new_root,
8486 struct btrfs_root *parent_root,
8489 struct inode *inode;
8493 inode = btrfs_new_inode(trans, new_root, NULL, "..", 2,
8494 new_dirid, new_dirid,
8495 S_IFDIR | (~current_umask() & S_IRWXUGO),
8498 return PTR_ERR(inode);
8499 inode->i_op = &btrfs_dir_inode_operations;
8500 inode->i_fop = &btrfs_dir_file_operations;
8502 set_nlink(inode, 1);
8503 btrfs_i_size_write(BTRFS_I(inode), 0);
8504 unlock_new_inode(inode);
8506 err = btrfs_subvol_inherit_props(trans, new_root, parent_root);
8508 btrfs_err(new_root->fs_info,
8509 "error inheriting subvolume %llu properties: %d",
8510 new_root->root_key.objectid, err);
8512 err = btrfs_update_inode(trans, new_root, inode);
8518 struct inode *btrfs_alloc_inode(struct super_block *sb)
8520 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
8521 struct btrfs_inode *ei;
8522 struct inode *inode;
8524 ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_KERNEL);
8531 ei->last_sub_trans = 0;
8532 ei->logged_trans = 0;
8533 ei->delalloc_bytes = 0;
8534 ei->new_delalloc_bytes = 0;
8535 ei->defrag_bytes = 0;
8536 ei->disk_i_size = 0;
8539 ei->index_cnt = (u64)-1;
8541 ei->last_unlink_trans = 0;
8542 ei->last_log_commit = 0;
8544 spin_lock_init(&ei->lock);
8545 ei->outstanding_extents = 0;
8546 if (sb->s_magic != BTRFS_TEST_MAGIC)
8547 btrfs_init_metadata_block_rsv(fs_info, &ei->block_rsv,
8548 BTRFS_BLOCK_RSV_DELALLOC);
8549 ei->runtime_flags = 0;
8550 ei->prop_compress = BTRFS_COMPRESS_NONE;
8551 ei->defrag_compress = BTRFS_COMPRESS_NONE;
8553 ei->delayed_node = NULL;
8555 ei->i_otime.tv_sec = 0;
8556 ei->i_otime.tv_nsec = 0;
8558 inode = &ei->vfs_inode;
8559 extent_map_tree_init(&ei->extent_tree);
8560 extent_io_tree_init(fs_info, &ei->io_tree, IO_TREE_INODE_IO, inode);
8561 extent_io_tree_init(fs_info, &ei->io_failure_tree,
8562 IO_TREE_INODE_IO_FAILURE, inode);
8563 extent_io_tree_init(fs_info, &ei->file_extent_tree,
8564 IO_TREE_INODE_FILE_EXTENT, inode);
8565 ei->io_tree.track_uptodate = true;
8566 ei->io_failure_tree.track_uptodate = true;
8567 atomic_set(&ei->sync_writers, 0);
8568 mutex_init(&ei->log_mutex);
8569 btrfs_ordered_inode_tree_init(&ei->ordered_tree);
8570 INIT_LIST_HEAD(&ei->delalloc_inodes);
8571 INIT_LIST_HEAD(&ei->delayed_iput);
8572 RB_CLEAR_NODE(&ei->rb_node);
8573 init_rwsem(&ei->dio_sem);
8578 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
8579 void btrfs_test_destroy_inode(struct inode *inode)
8581 btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0);
8582 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
8586 void btrfs_free_inode(struct inode *inode)
8588 kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
8591 void btrfs_destroy_inode(struct inode *inode)
8593 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
8594 struct btrfs_ordered_extent *ordered;
8595 struct btrfs_root *root = BTRFS_I(inode)->root;
8597 WARN_ON(!hlist_empty(&inode->i_dentry));
8598 WARN_ON(inode->i_data.nrpages);
8599 WARN_ON(BTRFS_I(inode)->block_rsv.reserved);
8600 WARN_ON(BTRFS_I(inode)->block_rsv.size);
8601 WARN_ON(BTRFS_I(inode)->outstanding_extents);
8602 WARN_ON(BTRFS_I(inode)->delalloc_bytes);
8603 WARN_ON(BTRFS_I(inode)->new_delalloc_bytes);
8604 WARN_ON(BTRFS_I(inode)->csum_bytes);
8605 WARN_ON(BTRFS_I(inode)->defrag_bytes);
8608 * This can happen where we create an inode, but somebody else also
8609 * created the same inode and we need to destroy the one we already
8616 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
8621 "found ordered extent %llu %llu on inode cleanup",
8622 ordered->file_offset, ordered->num_bytes);
8623 btrfs_remove_ordered_extent(inode, ordered);
8624 btrfs_put_ordered_extent(ordered);
8625 btrfs_put_ordered_extent(ordered);
8628 btrfs_qgroup_check_reserved_leak(inode);
8629 inode_tree_del(inode);
8630 btrfs_drop_extent_cache(BTRFS_I(inode), 0, (u64)-1, 0);
8631 btrfs_inode_clear_file_extent_range(BTRFS_I(inode), 0, (u64)-1);
8632 btrfs_put_root(BTRFS_I(inode)->root);
8635 int btrfs_drop_inode(struct inode *inode)
8637 struct btrfs_root *root = BTRFS_I(inode)->root;
8642 /* the snap/subvol tree is on deleting */
8643 if (btrfs_root_refs(&root->root_item) == 0)
8646 return generic_drop_inode(inode);
8649 static void init_once(void *foo)
8651 struct btrfs_inode *ei = (struct btrfs_inode *) foo;
8653 inode_init_once(&ei->vfs_inode);
8656 void __cold btrfs_destroy_cachep(void)
8659 * Make sure all delayed rcu free inodes are flushed before we
8663 kmem_cache_destroy(btrfs_inode_cachep);
8664 kmem_cache_destroy(btrfs_trans_handle_cachep);
8665 kmem_cache_destroy(btrfs_path_cachep);
8666 kmem_cache_destroy(btrfs_free_space_cachep);
8667 kmem_cache_destroy(btrfs_free_space_bitmap_cachep);
8670 int __init btrfs_init_cachep(void)
8672 btrfs_inode_cachep = kmem_cache_create("btrfs_inode",
8673 sizeof(struct btrfs_inode), 0,
8674 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD | SLAB_ACCOUNT,
8676 if (!btrfs_inode_cachep)
8679 btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle",
8680 sizeof(struct btrfs_trans_handle), 0,
8681 SLAB_TEMPORARY | SLAB_MEM_SPREAD, NULL);
8682 if (!btrfs_trans_handle_cachep)
8685 btrfs_path_cachep = kmem_cache_create("btrfs_path",
8686 sizeof(struct btrfs_path), 0,
8687 SLAB_MEM_SPREAD, NULL);
8688 if (!btrfs_path_cachep)
8691 btrfs_free_space_cachep = kmem_cache_create("btrfs_free_space",
8692 sizeof(struct btrfs_free_space), 0,
8693 SLAB_MEM_SPREAD, NULL);
8694 if (!btrfs_free_space_cachep)
8697 btrfs_free_space_bitmap_cachep = kmem_cache_create("btrfs_free_space_bitmap",
8698 PAGE_SIZE, PAGE_SIZE,
8699 SLAB_RED_ZONE, NULL);
8700 if (!btrfs_free_space_bitmap_cachep)
8705 btrfs_destroy_cachep();
8709 static int btrfs_getattr(const struct path *path, struct kstat *stat,
8710 u32 request_mask, unsigned int flags)
8713 struct inode *inode = d_inode(path->dentry);
8714 u32 blocksize = inode->i_sb->s_blocksize;
8715 u32 bi_flags = BTRFS_I(inode)->flags;
8717 stat->result_mask |= STATX_BTIME;
8718 stat->btime.tv_sec = BTRFS_I(inode)->i_otime.tv_sec;
8719 stat->btime.tv_nsec = BTRFS_I(inode)->i_otime.tv_nsec;
8720 if (bi_flags & BTRFS_INODE_APPEND)
8721 stat->attributes |= STATX_ATTR_APPEND;
8722 if (bi_flags & BTRFS_INODE_COMPRESS)
8723 stat->attributes |= STATX_ATTR_COMPRESSED;
8724 if (bi_flags & BTRFS_INODE_IMMUTABLE)
8725 stat->attributes |= STATX_ATTR_IMMUTABLE;
8726 if (bi_flags & BTRFS_INODE_NODUMP)
8727 stat->attributes |= STATX_ATTR_NODUMP;
8729 stat->attributes_mask |= (STATX_ATTR_APPEND |
8730 STATX_ATTR_COMPRESSED |
8731 STATX_ATTR_IMMUTABLE |
8734 generic_fillattr(inode, stat);
8735 stat->dev = BTRFS_I(inode)->root->anon_dev;
8737 spin_lock(&BTRFS_I(inode)->lock);
8738 delalloc_bytes = BTRFS_I(inode)->new_delalloc_bytes;
8739 spin_unlock(&BTRFS_I(inode)->lock);
8740 stat->blocks = (ALIGN(inode_get_bytes(inode), blocksize) +
8741 ALIGN(delalloc_bytes, blocksize)) >> 9;
8745 static int btrfs_rename_exchange(struct inode *old_dir,
8746 struct dentry *old_dentry,
8747 struct inode *new_dir,
8748 struct dentry *new_dentry)
8750 struct btrfs_fs_info *fs_info = btrfs_sb(old_dir->i_sb);
8751 struct btrfs_trans_handle *trans;
8752 struct btrfs_root *root = BTRFS_I(old_dir)->root;
8753 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
8754 struct inode *new_inode = new_dentry->d_inode;
8755 struct inode *old_inode = old_dentry->d_inode;
8756 struct timespec64 ctime = current_time(old_inode);
8757 struct dentry *parent;
8758 u64 old_ino = btrfs_ino(BTRFS_I(old_inode));
8759 u64 new_ino = btrfs_ino(BTRFS_I(new_inode));
8763 bool root_log_pinned = false;
8764 bool dest_log_pinned = false;
8765 struct btrfs_log_ctx ctx_root;
8766 struct btrfs_log_ctx ctx_dest;
8767 bool sync_log_root = false;
8768 bool sync_log_dest = false;
8769 bool commit_transaction = false;
8771 /* we only allow rename subvolume link between subvolumes */
8772 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
8775 btrfs_init_log_ctx(&ctx_root, old_inode);
8776 btrfs_init_log_ctx(&ctx_dest, new_inode);
8778 /* close the race window with snapshot create/destroy ioctl */
8779 if (old_ino == BTRFS_FIRST_FREE_OBJECTID ||
8780 new_ino == BTRFS_FIRST_FREE_OBJECTID)
8781 down_read(&fs_info->subvol_sem);
8784 * We want to reserve the absolute worst case amount of items. So if
8785 * both inodes are subvols and we need to unlink them then that would
8786 * require 4 item modifications, but if they are both normal inodes it
8787 * would require 5 item modifications, so we'll assume their normal
8788 * inodes. So 5 * 2 is 10, plus 2 for the new links, so 12 total items
8789 * should cover the worst case number of items we'll modify.
8791 trans = btrfs_start_transaction(root, 12);
8792 if (IS_ERR(trans)) {
8793 ret = PTR_ERR(trans);
8798 btrfs_record_root_in_trans(trans, dest);
8801 * We need to find a free sequence number both in the source and
8802 * in the destination directory for the exchange.
8804 ret = btrfs_set_inode_index(BTRFS_I(new_dir), &old_idx);
8807 ret = btrfs_set_inode_index(BTRFS_I(old_dir), &new_idx);
8811 BTRFS_I(old_inode)->dir_index = 0ULL;
8812 BTRFS_I(new_inode)->dir_index = 0ULL;
8814 /* Reference for the source. */
8815 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) {
8816 /* force full log commit if subvolume involved. */
8817 btrfs_set_log_full_commit(trans);
8819 btrfs_pin_log_trans(root);
8820 root_log_pinned = true;
8821 ret = btrfs_insert_inode_ref(trans, dest,
8822 new_dentry->d_name.name,
8823 new_dentry->d_name.len,
8825 btrfs_ino(BTRFS_I(new_dir)),
8831 /* And now for the dest. */
8832 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) {
8833 /* force full log commit if subvolume involved. */
8834 btrfs_set_log_full_commit(trans);
8836 btrfs_pin_log_trans(dest);
8837 dest_log_pinned = true;
8838 ret = btrfs_insert_inode_ref(trans, root,
8839 old_dentry->d_name.name,
8840 old_dentry->d_name.len,
8842 btrfs_ino(BTRFS_I(old_dir)),
8848 /* Update inode version and ctime/mtime. */
8849 inode_inc_iversion(old_dir);
8850 inode_inc_iversion(new_dir);
8851 inode_inc_iversion(old_inode);
8852 inode_inc_iversion(new_inode);
8853 old_dir->i_ctime = old_dir->i_mtime = ctime;
8854 new_dir->i_ctime = new_dir->i_mtime = ctime;
8855 old_inode->i_ctime = ctime;
8856 new_inode->i_ctime = ctime;
8858 if (old_dentry->d_parent != new_dentry->d_parent) {
8859 btrfs_record_unlink_dir(trans, BTRFS_I(old_dir),
8860 BTRFS_I(old_inode), 1);
8861 btrfs_record_unlink_dir(trans, BTRFS_I(new_dir),
8862 BTRFS_I(new_inode), 1);
8865 /* src is a subvolume */
8866 if (old_ino == BTRFS_FIRST_FREE_OBJECTID) {
8867 ret = btrfs_unlink_subvol(trans, old_dir, old_dentry);
8868 } else { /* src is an inode */
8869 ret = __btrfs_unlink_inode(trans, root, BTRFS_I(old_dir),
8870 BTRFS_I(old_dentry->d_inode),
8871 old_dentry->d_name.name,
8872 old_dentry->d_name.len);
8874 ret = btrfs_update_inode(trans, root, old_inode);
8877 btrfs_abort_transaction(trans, ret);
8881 /* dest is a subvolume */
8882 if (new_ino == BTRFS_FIRST_FREE_OBJECTID) {
8883 ret = btrfs_unlink_subvol(trans, new_dir, new_dentry);
8884 } else { /* dest is an inode */
8885 ret = __btrfs_unlink_inode(trans, dest, BTRFS_I(new_dir),
8886 BTRFS_I(new_dentry->d_inode),
8887 new_dentry->d_name.name,
8888 new_dentry->d_name.len);
8890 ret = btrfs_update_inode(trans, dest, new_inode);
8893 btrfs_abort_transaction(trans, ret);
8897 ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode),
8898 new_dentry->d_name.name,
8899 new_dentry->d_name.len, 0, old_idx);
8901 btrfs_abort_transaction(trans, ret);
8905 ret = btrfs_add_link(trans, BTRFS_I(old_dir), BTRFS_I(new_inode),
8906 old_dentry->d_name.name,
8907 old_dentry->d_name.len, 0, new_idx);
8909 btrfs_abort_transaction(trans, ret);
8913 if (old_inode->i_nlink == 1)
8914 BTRFS_I(old_inode)->dir_index = old_idx;
8915 if (new_inode->i_nlink == 1)
8916 BTRFS_I(new_inode)->dir_index = new_idx;
8918 if (root_log_pinned) {
8919 parent = new_dentry->d_parent;
8920 ret = btrfs_log_new_name(trans, BTRFS_I(old_inode),
8921 BTRFS_I(old_dir), parent,
8923 if (ret == BTRFS_NEED_LOG_SYNC)
8924 sync_log_root = true;
8925 else if (ret == BTRFS_NEED_TRANS_COMMIT)
8926 commit_transaction = true;
8928 btrfs_end_log_trans(root);
8929 root_log_pinned = false;
8931 if (dest_log_pinned) {
8932 if (!commit_transaction) {
8933 parent = old_dentry->d_parent;
8934 ret = btrfs_log_new_name(trans, BTRFS_I(new_inode),
8935 BTRFS_I(new_dir), parent,
8937 if (ret == BTRFS_NEED_LOG_SYNC)
8938 sync_log_dest = true;
8939 else if (ret == BTRFS_NEED_TRANS_COMMIT)
8940 commit_transaction = true;
8943 btrfs_end_log_trans(dest);
8944 dest_log_pinned = false;
8948 * If we have pinned a log and an error happened, we unpin tasks
8949 * trying to sync the log and force them to fallback to a transaction
8950 * commit if the log currently contains any of the inodes involved in
8951 * this rename operation (to ensure we do not persist a log with an
8952 * inconsistent state for any of these inodes or leading to any
8953 * inconsistencies when replayed). If the transaction was aborted, the
8954 * abortion reason is propagated to userspace when attempting to commit
8955 * the transaction. If the log does not contain any of these inodes, we
8956 * allow the tasks to sync it.
8958 if (ret && (root_log_pinned || dest_log_pinned)) {
8959 if (btrfs_inode_in_log(BTRFS_I(old_dir), fs_info->generation) ||
8960 btrfs_inode_in_log(BTRFS_I(new_dir), fs_info->generation) ||
8961 btrfs_inode_in_log(BTRFS_I(old_inode), fs_info->generation) ||
8963 btrfs_inode_in_log(BTRFS_I(new_inode), fs_info->generation)))
8964 btrfs_set_log_full_commit(trans);
8966 if (root_log_pinned) {
8967 btrfs_end_log_trans(root);
8968 root_log_pinned = false;
8970 if (dest_log_pinned) {
8971 btrfs_end_log_trans(dest);
8972 dest_log_pinned = false;
8975 if (!ret && sync_log_root && !commit_transaction) {
8976 ret = btrfs_sync_log(trans, BTRFS_I(old_inode)->root,
8979 commit_transaction = true;
8981 if (!ret && sync_log_dest && !commit_transaction) {
8982 ret = btrfs_sync_log(trans, BTRFS_I(new_inode)->root,
8985 commit_transaction = true;
8987 if (commit_transaction) {
8989 * We may have set commit_transaction when logging the new name
8990 * in the destination root, in which case we left the source
8991 * root context in the list of log contextes. So make sure we
8992 * remove it to avoid invalid memory accesses, since the context
8993 * was allocated in our stack frame.
8995 if (sync_log_root) {
8996 mutex_lock(&root->log_mutex);
8997 list_del_init(&ctx_root.list);
8998 mutex_unlock(&root->log_mutex);
9000 ret = btrfs_commit_transaction(trans);
9004 ret2 = btrfs_end_transaction(trans);
9005 ret = ret ? ret : ret2;
9008 if (new_ino == BTRFS_FIRST_FREE_OBJECTID ||
9009 old_ino == BTRFS_FIRST_FREE_OBJECTID)
9010 up_read(&fs_info->subvol_sem);
9012 ASSERT(list_empty(&ctx_root.list));
9013 ASSERT(list_empty(&ctx_dest.list));
9018 static int btrfs_whiteout_for_rename(struct btrfs_trans_handle *trans,
9019 struct btrfs_root *root,
9021 struct dentry *dentry)
9024 struct inode *inode;
9028 ret = btrfs_find_free_ino(root, &objectid);
9032 inode = btrfs_new_inode(trans, root, dir,
9033 dentry->d_name.name,
9035 btrfs_ino(BTRFS_I(dir)),
9037 S_IFCHR | WHITEOUT_MODE,
9040 if (IS_ERR(inode)) {
9041 ret = PTR_ERR(inode);
9045 inode->i_op = &btrfs_special_inode_operations;
9046 init_special_inode(inode, inode->i_mode,
9049 ret = btrfs_init_inode_security(trans, inode, dir,
9054 ret = btrfs_add_nondir(trans, BTRFS_I(dir), dentry,
9055 BTRFS_I(inode), 0, index);
9059 ret = btrfs_update_inode(trans, root, inode);
9061 unlock_new_inode(inode);
9063 inode_dec_link_count(inode);
9069 static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
9070 struct inode *new_dir, struct dentry *new_dentry,
9073 struct btrfs_fs_info *fs_info = btrfs_sb(old_dir->i_sb);
9074 struct btrfs_trans_handle *trans;
9075 unsigned int trans_num_items;
9076 struct btrfs_root *root = BTRFS_I(old_dir)->root;
9077 struct btrfs_root *dest = BTRFS_I(new_dir)->root;
9078 struct inode *new_inode = d_inode(new_dentry);
9079 struct inode *old_inode = d_inode(old_dentry);
9082 u64 old_ino = btrfs_ino(BTRFS_I(old_inode));
9083 bool log_pinned = false;
9084 struct btrfs_log_ctx ctx;
9085 bool sync_log = false;
9086 bool commit_transaction = false;
9088 if (btrfs_ino(BTRFS_I(new_dir)) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
9091 /* we only allow rename subvolume link between subvolumes */
9092 if (old_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
9095 if (old_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
9096 (new_inode && btrfs_ino(BTRFS_I(new_inode)) == BTRFS_FIRST_FREE_OBJECTID))
9099 if (S_ISDIR(old_inode->i_mode) && new_inode &&
9100 new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
9104 /* check for collisions, even if the name isn't there */
9105 ret = btrfs_check_dir_item_collision(dest, new_dir->i_ino,
9106 new_dentry->d_name.name,
9107 new_dentry->d_name.len);
9110 if (ret == -EEXIST) {
9112 * eexist without a new_inode */
9113 if (WARN_ON(!new_inode)) {
9117 /* maybe -EOVERFLOW */
9124 * we're using rename to replace one file with another. Start IO on it
9125 * now so we don't add too much work to the end of the transaction
9127 if (new_inode && S_ISREG(old_inode->i_mode) && new_inode->i_size)
9128 filemap_flush(old_inode->i_mapping);
9130 /* close the racy window with snapshot create/destroy ioctl */
9131 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
9132 down_read(&fs_info->subvol_sem);
9134 * We want to reserve the absolute worst case amount of items. So if
9135 * both inodes are subvols and we need to unlink them then that would
9136 * require 4 item modifications, but if they are both normal inodes it
9137 * would require 5 item modifications, so we'll assume they are normal
9138 * inodes. So 5 * 2 is 10, plus 1 for the new link, so 11 total items
9139 * should cover the worst case number of items we'll modify.
9140 * If our rename has the whiteout flag, we need more 5 units for the
9141 * new inode (1 inode item, 1 inode ref, 2 dir items and 1 xattr item
9142 * when selinux is enabled).
9144 trans_num_items = 11;
9145 if (flags & RENAME_WHITEOUT)
9146 trans_num_items += 5;
9147 trans = btrfs_start_transaction(root, trans_num_items);
9148 if (IS_ERR(trans)) {
9149 ret = PTR_ERR(trans);
9154 btrfs_record_root_in_trans(trans, dest);
9156 ret = btrfs_set_inode_index(BTRFS_I(new_dir), &index);
9160 BTRFS_I(old_inode)->dir_index = 0ULL;
9161 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
9162 /* force full log commit if subvolume involved. */
9163 btrfs_set_log_full_commit(trans);
9165 btrfs_pin_log_trans(root);
9167 ret = btrfs_insert_inode_ref(trans, dest,
9168 new_dentry->d_name.name,
9169 new_dentry->d_name.len,
9171 btrfs_ino(BTRFS_I(new_dir)), index);
9176 inode_inc_iversion(old_dir);
9177 inode_inc_iversion(new_dir);
9178 inode_inc_iversion(old_inode);
9179 old_dir->i_ctime = old_dir->i_mtime =
9180 new_dir->i_ctime = new_dir->i_mtime =
9181 old_inode->i_ctime = current_time(old_dir);
9183 if (old_dentry->d_parent != new_dentry->d_parent)
9184 btrfs_record_unlink_dir(trans, BTRFS_I(old_dir),
9185 BTRFS_I(old_inode), 1);
9187 if (unlikely(old_ino == BTRFS_FIRST_FREE_OBJECTID)) {
9188 ret = btrfs_unlink_subvol(trans, old_dir, old_dentry);
9190 ret = __btrfs_unlink_inode(trans, root, BTRFS_I(old_dir),
9191 BTRFS_I(d_inode(old_dentry)),
9192 old_dentry->d_name.name,
9193 old_dentry->d_name.len);
9195 ret = btrfs_update_inode(trans, root, old_inode);
9198 btrfs_abort_transaction(trans, ret);
9203 inode_inc_iversion(new_inode);
9204 new_inode->i_ctime = current_time(new_inode);
9205 if (unlikely(btrfs_ino(BTRFS_I(new_inode)) ==
9206 BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
9207 ret = btrfs_unlink_subvol(trans, new_dir, new_dentry);
9208 BUG_ON(new_inode->i_nlink == 0);
9210 ret = btrfs_unlink_inode(trans, dest, BTRFS_I(new_dir),
9211 BTRFS_I(d_inode(new_dentry)),
9212 new_dentry->d_name.name,
9213 new_dentry->d_name.len);
9215 if (!ret && new_inode->i_nlink == 0)
9216 ret = btrfs_orphan_add(trans,
9217 BTRFS_I(d_inode(new_dentry)));
9219 btrfs_abort_transaction(trans, ret);
9224 ret = btrfs_add_link(trans, BTRFS_I(new_dir), BTRFS_I(old_inode),
9225 new_dentry->d_name.name,
9226 new_dentry->d_name.len, 0, index);
9228 btrfs_abort_transaction(trans, ret);
9232 if (old_inode->i_nlink == 1)
9233 BTRFS_I(old_inode)->dir_index = index;
9236 struct dentry *parent = new_dentry->d_parent;
9238 btrfs_init_log_ctx(&ctx, old_inode);
9239 ret = btrfs_log_new_name(trans, BTRFS_I(old_inode),
9240 BTRFS_I(old_dir), parent,
9242 if (ret == BTRFS_NEED_LOG_SYNC)
9244 else if (ret == BTRFS_NEED_TRANS_COMMIT)
9245 commit_transaction = true;
9247 btrfs_end_log_trans(root);
9251 if (flags & RENAME_WHITEOUT) {
9252 ret = btrfs_whiteout_for_rename(trans, root, old_dir,
9256 btrfs_abort_transaction(trans, ret);
9262 * If we have pinned the log and an error happened, we unpin tasks
9263 * trying to sync the log and force them to fallback to a transaction
9264 * commit if the log currently contains any of the inodes involved in
9265 * this rename operation (to ensure we do not persist a log with an
9266 * inconsistent state for any of these inodes or leading to any
9267 * inconsistencies when replayed). If the transaction was aborted, the
9268 * abortion reason is propagated to userspace when attempting to commit
9269 * the transaction. If the log does not contain any of these inodes, we
9270 * allow the tasks to sync it.
9272 if (ret && log_pinned) {
9273 if (btrfs_inode_in_log(BTRFS_I(old_dir), fs_info->generation) ||
9274 btrfs_inode_in_log(BTRFS_I(new_dir), fs_info->generation) ||
9275 btrfs_inode_in_log(BTRFS_I(old_inode), fs_info->generation) ||
9277 btrfs_inode_in_log(BTRFS_I(new_inode), fs_info->generation)))
9278 btrfs_set_log_full_commit(trans);
9280 btrfs_end_log_trans(root);
9283 if (!ret && sync_log) {
9284 ret = btrfs_sync_log(trans, BTRFS_I(old_inode)->root, &ctx);
9286 commit_transaction = true;
9287 } else if (sync_log) {
9288 mutex_lock(&root->log_mutex);
9289 list_del(&ctx.list);
9290 mutex_unlock(&root->log_mutex);
9292 if (commit_transaction) {
9293 ret = btrfs_commit_transaction(trans);
9297 ret2 = btrfs_end_transaction(trans);
9298 ret = ret ? ret : ret2;
9301 if (old_ino == BTRFS_FIRST_FREE_OBJECTID)
9302 up_read(&fs_info->subvol_sem);
9307 static int btrfs_rename2(struct inode *old_dir, struct dentry *old_dentry,
9308 struct inode *new_dir, struct dentry *new_dentry,
9311 if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
9314 if (flags & RENAME_EXCHANGE)
9315 return btrfs_rename_exchange(old_dir, old_dentry, new_dir,
9318 return btrfs_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
9321 struct btrfs_delalloc_work {
9322 struct inode *inode;
9323 struct completion completion;
9324 struct list_head list;
9325 struct btrfs_work work;
9328 static void btrfs_run_delalloc_work(struct btrfs_work *work)
9330 struct btrfs_delalloc_work *delalloc_work;
9331 struct inode *inode;
9333 delalloc_work = container_of(work, struct btrfs_delalloc_work,
9335 inode = delalloc_work->inode;
9336 filemap_flush(inode->i_mapping);
9337 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
9338 &BTRFS_I(inode)->runtime_flags))
9339 filemap_flush(inode->i_mapping);
9342 complete(&delalloc_work->completion);
9345 static struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode)
9347 struct btrfs_delalloc_work *work;
9349 work = kmalloc(sizeof(*work), GFP_NOFS);
9353 init_completion(&work->completion);
9354 INIT_LIST_HEAD(&work->list);
9355 work->inode = inode;
9356 btrfs_init_work(&work->work, btrfs_run_delalloc_work, NULL, NULL);
9362 * some fairly slow code that needs optimization. This walks the list
9363 * of all the inodes with pending delalloc and forces them to disk.
9365 static int start_delalloc_inodes(struct btrfs_root *root, int nr, bool snapshot)
9367 struct btrfs_inode *binode;
9368 struct inode *inode;
9369 struct btrfs_delalloc_work *work, *next;
9370 struct list_head works;
9371 struct list_head splice;
9374 INIT_LIST_HEAD(&works);
9375 INIT_LIST_HEAD(&splice);
9377 mutex_lock(&root->delalloc_mutex);
9378 spin_lock(&root->delalloc_lock);
9379 list_splice_init(&root->delalloc_inodes, &splice);
9380 while (!list_empty(&splice)) {
9381 binode = list_entry(splice.next, struct btrfs_inode,
9384 list_move_tail(&binode->delalloc_inodes,
9385 &root->delalloc_inodes);
9386 inode = igrab(&binode->vfs_inode);
9388 cond_resched_lock(&root->delalloc_lock);
9391 spin_unlock(&root->delalloc_lock);
9394 set_bit(BTRFS_INODE_SNAPSHOT_FLUSH,
9395 &binode->runtime_flags);
9396 work = btrfs_alloc_delalloc_work(inode);
9402 list_add_tail(&work->list, &works);
9403 btrfs_queue_work(root->fs_info->flush_workers,
9406 if (nr != -1 && ret >= nr)
9409 spin_lock(&root->delalloc_lock);
9411 spin_unlock(&root->delalloc_lock);
9414 list_for_each_entry_safe(work, next, &works, list) {
9415 list_del_init(&work->list);
9416 wait_for_completion(&work->completion);
9420 if (!list_empty(&splice)) {
9421 spin_lock(&root->delalloc_lock);
9422 list_splice_tail(&splice, &root->delalloc_inodes);
9423 spin_unlock(&root->delalloc_lock);
9425 mutex_unlock(&root->delalloc_mutex);
9429 int btrfs_start_delalloc_snapshot(struct btrfs_root *root)
9431 struct btrfs_fs_info *fs_info = root->fs_info;
9434 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
9437 ret = start_delalloc_inodes(root, -1, true);
9443 int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, int nr)
9445 struct btrfs_root *root;
9446 struct list_head splice;
9449 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
9452 INIT_LIST_HEAD(&splice);
9454 mutex_lock(&fs_info->delalloc_root_mutex);
9455 spin_lock(&fs_info->delalloc_root_lock);
9456 list_splice_init(&fs_info->delalloc_roots, &splice);
9457 while (!list_empty(&splice) && nr) {
9458 root = list_first_entry(&splice, struct btrfs_root,
9460 root = btrfs_grab_root(root);
9462 list_move_tail(&root->delalloc_root,
9463 &fs_info->delalloc_roots);
9464 spin_unlock(&fs_info->delalloc_root_lock);
9466 ret = start_delalloc_inodes(root, nr, false);
9467 btrfs_put_root(root);
9475 spin_lock(&fs_info->delalloc_root_lock);
9477 spin_unlock(&fs_info->delalloc_root_lock);
9481 if (!list_empty(&splice)) {
9482 spin_lock(&fs_info->delalloc_root_lock);
9483 list_splice_tail(&splice, &fs_info->delalloc_roots);
9484 spin_unlock(&fs_info->delalloc_root_lock);
9486 mutex_unlock(&fs_info->delalloc_root_mutex);
9490 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
9491 const char *symname)
9493 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
9494 struct btrfs_trans_handle *trans;
9495 struct btrfs_root *root = BTRFS_I(dir)->root;
9496 struct btrfs_path *path;
9497 struct btrfs_key key;
9498 struct inode *inode = NULL;
9505 struct btrfs_file_extent_item *ei;
9506 struct extent_buffer *leaf;
9508 name_len = strlen(symname);
9509 if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info))
9510 return -ENAMETOOLONG;
9513 * 2 items for inode item and ref
9514 * 2 items for dir items
9515 * 1 item for updating parent inode item
9516 * 1 item for the inline extent item
9517 * 1 item for xattr if selinux is on
9519 trans = btrfs_start_transaction(root, 7);
9521 return PTR_ERR(trans);
9523 err = btrfs_find_free_ino(root, &objectid);
9527 inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
9528 dentry->d_name.len, btrfs_ino(BTRFS_I(dir)),
9529 objectid, S_IFLNK|S_IRWXUGO, &index);
9530 if (IS_ERR(inode)) {
9531 err = PTR_ERR(inode);
9537 * If the active LSM wants to access the inode during
9538 * d_instantiate it needs these. Smack checks to see
9539 * if the filesystem supports xattrs by looking at the
9542 inode->i_fop = &btrfs_file_operations;
9543 inode->i_op = &btrfs_file_inode_operations;
9544 inode->i_mapping->a_ops = &btrfs_aops;
9545 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
9547 err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
9551 path = btrfs_alloc_path();
9556 key.objectid = btrfs_ino(BTRFS_I(inode));
9558 key.type = BTRFS_EXTENT_DATA_KEY;
9559 datasize = btrfs_file_extent_calc_inline_size(name_len);
9560 err = btrfs_insert_empty_item(trans, root, path, &key,
9563 btrfs_free_path(path);
9566 leaf = path->nodes[0];
9567 ei = btrfs_item_ptr(leaf, path->slots[0],
9568 struct btrfs_file_extent_item);
9569 btrfs_set_file_extent_generation(leaf, ei, trans->transid);
9570 btrfs_set_file_extent_type(leaf, ei,
9571 BTRFS_FILE_EXTENT_INLINE);
9572 btrfs_set_file_extent_encryption(leaf, ei, 0);
9573 btrfs_set_file_extent_compression(leaf, ei, 0);
9574 btrfs_set_file_extent_other_encoding(leaf, ei, 0);
9575 btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
9577 ptr = btrfs_file_extent_inline_start(ei);
9578 write_extent_buffer(leaf, symname, ptr, name_len);
9579 btrfs_mark_buffer_dirty(leaf);
9580 btrfs_free_path(path);
9582 inode->i_op = &btrfs_symlink_inode_operations;
9583 inode_nohighmem(inode);
9584 inode_set_bytes(inode, name_len);
9585 btrfs_i_size_write(BTRFS_I(inode), name_len);
9586 err = btrfs_update_inode(trans, root, inode);
9588 * Last step, add directory indexes for our symlink inode. This is the
9589 * last step to avoid extra cleanup of these indexes if an error happens
9593 err = btrfs_add_nondir(trans, BTRFS_I(dir), dentry,
9594 BTRFS_I(inode), 0, index);
9598 d_instantiate_new(dentry, inode);
9601 btrfs_end_transaction(trans);
9603 inode_dec_link_count(inode);
9604 discard_new_inode(inode);
9606 btrfs_btree_balance_dirty(fs_info);
9610 static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
9611 u64 start, u64 num_bytes, u64 min_size,
9612 loff_t actual_len, u64 *alloc_hint,
9613 struct btrfs_trans_handle *trans)
9615 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
9616 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
9617 struct extent_map *em;
9618 struct btrfs_root *root = BTRFS_I(inode)->root;
9619 struct btrfs_key ins;
9620 u64 cur_offset = start;
9621 u64 clear_offset = start;
9624 u64 last_alloc = (u64)-1;
9626 bool own_trans = true;
9627 u64 end = start + num_bytes - 1;
9631 while (num_bytes > 0) {
9633 trans = btrfs_start_transaction(root, 3);
9634 if (IS_ERR(trans)) {
9635 ret = PTR_ERR(trans);
9640 cur_bytes = min_t(u64, num_bytes, SZ_256M);
9641 cur_bytes = max(cur_bytes, min_size);
9643 * If we are severely fragmented we could end up with really
9644 * small allocations, so if the allocator is returning small
9645 * chunks lets make its job easier by only searching for those
9648 cur_bytes = min(cur_bytes, last_alloc);
9649 ret = btrfs_reserve_extent(root, cur_bytes, cur_bytes,
9650 min_size, 0, *alloc_hint, &ins, 1, 0);
9653 btrfs_end_transaction(trans);
9658 * We've reserved this space, and thus converted it from
9659 * ->bytes_may_use to ->bytes_reserved. Any error that happens
9660 * from here on out we will only need to clear our reservation
9661 * for the remaining unreserved area, so advance our
9662 * clear_offset by our extent size.
9664 clear_offset += ins.offset;
9665 btrfs_dec_block_group_reservations(fs_info, ins.objectid);
9667 last_alloc = ins.offset;
9668 ret = insert_reserved_file_extent(trans, inode,
9669 cur_offset, ins.objectid,
9670 ins.offset, ins.offset,
9671 ins.offset, 0, 0, 0,
9672 BTRFS_FILE_EXTENT_PREALLOC);
9674 btrfs_free_reserved_extent(fs_info, ins.objectid,
9676 btrfs_abort_transaction(trans, ret);
9678 btrfs_end_transaction(trans);
9682 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset,
9683 cur_offset + ins.offset -1, 0);
9685 em = alloc_extent_map();
9687 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
9688 &BTRFS_I(inode)->runtime_flags);
9692 em->start = cur_offset;
9693 em->orig_start = cur_offset;
9694 em->len = ins.offset;
9695 em->block_start = ins.objectid;
9696 em->block_len = ins.offset;
9697 em->orig_block_len = ins.offset;
9698 em->ram_bytes = ins.offset;
9699 set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
9700 em->generation = trans->transid;
9703 write_lock(&em_tree->lock);
9704 ret = add_extent_mapping(em_tree, em, 1);
9705 write_unlock(&em_tree->lock);
9708 btrfs_drop_extent_cache(BTRFS_I(inode), cur_offset,
9709 cur_offset + ins.offset - 1,
9712 free_extent_map(em);
9714 num_bytes -= ins.offset;
9715 cur_offset += ins.offset;
9716 *alloc_hint = ins.objectid + ins.offset;
9718 inode_inc_iversion(inode);
9719 inode->i_ctime = current_time(inode);
9720 BTRFS_I(inode)->flags |= BTRFS_INODE_PREALLOC;
9721 if (!(mode & FALLOC_FL_KEEP_SIZE) &&
9722 (actual_len > inode->i_size) &&
9723 (cur_offset > inode->i_size)) {
9724 if (cur_offset > actual_len)
9725 i_size = actual_len;
9727 i_size = cur_offset;
9728 i_size_write(inode, i_size);
9729 btrfs_inode_safe_disk_i_size_write(inode, 0);
9732 ret = btrfs_update_inode(trans, root, inode);
9735 btrfs_abort_transaction(trans, ret);
9737 btrfs_end_transaction(trans);
9742 btrfs_end_transaction(trans);
9744 if (clear_offset < end)
9745 btrfs_free_reserved_data_space(inode, NULL, clear_offset,
9746 end - clear_offset + 1);
9750 int btrfs_prealloc_file_range(struct inode *inode, int mode,
9751 u64 start, u64 num_bytes, u64 min_size,
9752 loff_t actual_len, u64 *alloc_hint)
9754 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
9755 min_size, actual_len, alloc_hint,
9759 int btrfs_prealloc_file_range_trans(struct inode *inode,
9760 struct btrfs_trans_handle *trans, int mode,
9761 u64 start, u64 num_bytes, u64 min_size,
9762 loff_t actual_len, u64 *alloc_hint)
9764 return __btrfs_prealloc_file_range(inode, mode, start, num_bytes,
9765 min_size, actual_len, alloc_hint, trans);
9768 static int btrfs_set_page_dirty(struct page *page)
9770 return __set_page_dirty_nobuffers(page);
9773 static int btrfs_permission(struct inode *inode, int mask)
9775 struct btrfs_root *root = BTRFS_I(inode)->root;
9776 umode_t mode = inode->i_mode;
9778 if (mask & MAY_WRITE &&
9779 (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) {
9780 if (btrfs_root_readonly(root))
9782 if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
9785 return generic_permission(inode, mask);
9788 static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
9790 struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
9791 struct btrfs_trans_handle *trans;
9792 struct btrfs_root *root = BTRFS_I(dir)->root;
9793 struct inode *inode = NULL;
9799 * 5 units required for adding orphan entry
9801 trans = btrfs_start_transaction(root, 5);
9803 return PTR_ERR(trans);
9805 ret = btrfs_find_free_ino(root, &objectid);
9809 inode = btrfs_new_inode(trans, root, dir, NULL, 0,
9810 btrfs_ino(BTRFS_I(dir)), objectid, mode, &index);
9811 if (IS_ERR(inode)) {
9812 ret = PTR_ERR(inode);
9817 inode->i_fop = &btrfs_file_operations;
9818 inode->i_op = &btrfs_file_inode_operations;
9820 inode->i_mapping->a_ops = &btrfs_aops;
9821 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
9823 ret = btrfs_init_inode_security(trans, inode, dir, NULL);
9827 ret = btrfs_update_inode(trans, root, inode);
9830 ret = btrfs_orphan_add(trans, BTRFS_I(inode));
9835 * We set number of links to 0 in btrfs_new_inode(), and here we set
9836 * it to 1 because d_tmpfile() will issue a warning if the count is 0,
9839 * d_tmpfile() -> inode_dec_link_count() -> drop_nlink()
9841 set_nlink(inode, 1);
9842 d_tmpfile(dentry, inode);
9843 unlock_new_inode(inode);
9844 mark_inode_dirty(inode);
9846 btrfs_end_transaction(trans);
9848 discard_new_inode(inode);
9849 btrfs_btree_balance_dirty(fs_info);
9853 void btrfs_set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end)
9855 struct inode *inode = tree->private_data;
9856 unsigned long index = start >> PAGE_SHIFT;
9857 unsigned long end_index = end >> PAGE_SHIFT;
9860 while (index <= end_index) {
9861 page = find_get_page(inode->i_mapping, index);
9862 ASSERT(page); /* Pages should be in the extent_io_tree */
9863 set_page_writeback(page);
9871 * Add an entry indicating a block group or device which is pinned by a
9872 * swapfile. Returns 0 on success, 1 if there is already an entry for it, or a
9873 * negative errno on failure.
9875 static int btrfs_add_swapfile_pin(struct inode *inode, void *ptr,
9876 bool is_block_group)
9878 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
9879 struct btrfs_swapfile_pin *sp, *entry;
9881 struct rb_node *parent = NULL;
9883 sp = kmalloc(sizeof(*sp), GFP_NOFS);
9888 sp->is_block_group = is_block_group;
9890 spin_lock(&fs_info->swapfile_pins_lock);
9891 p = &fs_info->swapfile_pins.rb_node;
9894 entry = rb_entry(parent, struct btrfs_swapfile_pin, node);
9895 if (sp->ptr < entry->ptr ||
9896 (sp->ptr == entry->ptr && sp->inode < entry->inode)) {
9898 } else if (sp->ptr > entry->ptr ||
9899 (sp->ptr == entry->ptr && sp->inode > entry->inode)) {
9900 p = &(*p)->rb_right;
9902 spin_unlock(&fs_info->swapfile_pins_lock);
9907 rb_link_node(&sp->node, parent, p);
9908 rb_insert_color(&sp->node, &fs_info->swapfile_pins);
9909 spin_unlock(&fs_info->swapfile_pins_lock);
9913 /* Free all of the entries pinned by this swapfile. */
9914 static void btrfs_free_swapfile_pins(struct inode *inode)
9916 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
9917 struct btrfs_swapfile_pin *sp;
9918 struct rb_node *node, *next;
9920 spin_lock(&fs_info->swapfile_pins_lock);
9921 node = rb_first(&fs_info->swapfile_pins);
9923 next = rb_next(node);
9924 sp = rb_entry(node, struct btrfs_swapfile_pin, node);
9925 if (sp->inode == inode) {
9926 rb_erase(&sp->node, &fs_info->swapfile_pins);
9927 if (sp->is_block_group)
9928 btrfs_put_block_group(sp->ptr);
9933 spin_unlock(&fs_info->swapfile_pins_lock);
9936 struct btrfs_swap_info {
9942 unsigned long nr_pages;
9946 static int btrfs_add_swap_extent(struct swap_info_struct *sis,
9947 struct btrfs_swap_info *bsi)
9949 unsigned long nr_pages;
9950 u64 first_ppage, first_ppage_reported, next_ppage;
9953 first_ppage = ALIGN(bsi->block_start, PAGE_SIZE) >> PAGE_SHIFT;
9954 next_ppage = ALIGN_DOWN(bsi->block_start + bsi->block_len,
9955 PAGE_SIZE) >> PAGE_SHIFT;
9957 if (first_ppage >= next_ppage)
9959 nr_pages = next_ppage - first_ppage;
9961 first_ppage_reported = first_ppage;
9962 if (bsi->start == 0)
9963 first_ppage_reported++;
9964 if (bsi->lowest_ppage > first_ppage_reported)
9965 bsi->lowest_ppage = first_ppage_reported;
9966 if (bsi->highest_ppage < (next_ppage - 1))
9967 bsi->highest_ppage = next_ppage - 1;
9969 ret = add_swap_extent(sis, bsi->nr_pages, nr_pages, first_ppage);
9972 bsi->nr_extents += ret;
9973 bsi->nr_pages += nr_pages;
9977 static void btrfs_swap_deactivate(struct file *file)
9979 struct inode *inode = file_inode(file);
9981 btrfs_free_swapfile_pins(inode);
9982 atomic_dec(&BTRFS_I(inode)->root->nr_swapfiles);
9985 static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
9988 struct inode *inode = file_inode(file);
9989 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
9990 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
9991 struct extent_state *cached_state = NULL;
9992 struct extent_map *em = NULL;
9993 struct btrfs_device *device = NULL;
9994 struct btrfs_swap_info bsi = {
9995 .lowest_ppage = (sector_t)-1ULL,
10002 * If the swap file was just created, make sure delalloc is done. If the
10003 * file changes again after this, the user is doing something stupid and
10004 * we don't really care.
10006 ret = btrfs_wait_ordered_range(inode, 0, (u64)-1);
10011 * The inode is locked, so these flags won't change after we check them.
10013 if (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS) {
10014 btrfs_warn(fs_info, "swapfile must not be compressed");
10017 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW)) {
10018 btrfs_warn(fs_info, "swapfile must not be copy-on-write");
10021 if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
10022 btrfs_warn(fs_info, "swapfile must not be checksummed");
10027 * Balance or device remove/replace/resize can move stuff around from
10028 * under us. The EXCL_OP flag makes sure they aren't running/won't run
10029 * concurrently while we are mapping the swap extents, and
10030 * fs_info->swapfile_pins prevents them from running while the swap file
10031 * is active and moving the extents. Note that this also prevents a
10032 * concurrent device add which isn't actually necessary, but it's not
10033 * really worth the trouble to allow it.
10035 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
10036 btrfs_warn(fs_info,
10037 "cannot activate swapfile while exclusive operation is running");
10041 * Snapshots can create extents which require COW even if NODATACOW is
10042 * set. We use this counter to prevent snapshots. We must increment it
10043 * before walking the extents because we don't want a concurrent
10044 * snapshot to run after we've already checked the extents.
10046 atomic_inc(&BTRFS_I(inode)->root->nr_swapfiles);
10048 isize = ALIGN_DOWN(inode->i_size, fs_info->sectorsize);
10050 lock_extent_bits(io_tree, 0, isize - 1, &cached_state);
10052 while (start < isize) {
10053 u64 logical_block_start, physical_block_start;
10054 struct btrfs_block_group *bg;
10055 u64 len = isize - start;
10057 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len);
10063 if (em->block_start == EXTENT_MAP_HOLE) {
10064 btrfs_warn(fs_info, "swapfile must not have holes");
10068 if (em->block_start == EXTENT_MAP_INLINE) {
10070 * It's unlikely we'll ever actually find ourselves
10071 * here, as a file small enough to fit inline won't be
10072 * big enough to store more than the swap header, but in
10073 * case something changes in the future, let's catch it
10074 * here rather than later.
10076 btrfs_warn(fs_info, "swapfile must not be inline");
10080 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
10081 btrfs_warn(fs_info, "swapfile must not be compressed");
10086 logical_block_start = em->block_start + (start - em->start);
10087 len = min(len, em->len - (start - em->start));
10088 free_extent_map(em);
10091 ret = can_nocow_extent(inode, start, &len, NULL, NULL, NULL);
10097 btrfs_warn(fs_info,
10098 "swapfile must not be copy-on-write");
10103 em = btrfs_get_chunk_map(fs_info, logical_block_start, len);
10109 if (em->map_lookup->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
10110 btrfs_warn(fs_info,
10111 "swapfile must have single data profile");
10116 if (device == NULL) {
10117 device = em->map_lookup->stripes[0].dev;
10118 ret = btrfs_add_swapfile_pin(inode, device, false);
10123 } else if (device != em->map_lookup->stripes[0].dev) {
10124 btrfs_warn(fs_info, "swapfile must be on one device");
10129 physical_block_start = (em->map_lookup->stripes[0].physical +
10130 (logical_block_start - em->start));
10131 len = min(len, em->len - (logical_block_start - em->start));
10132 free_extent_map(em);
10135 bg = btrfs_lookup_block_group(fs_info, logical_block_start);
10137 btrfs_warn(fs_info,
10138 "could not find block group containing swapfile");
10143 ret = btrfs_add_swapfile_pin(inode, bg, true);
10145 btrfs_put_block_group(bg);
10152 if (bsi.block_len &&
10153 bsi.block_start + bsi.block_len == physical_block_start) {
10154 bsi.block_len += len;
10156 if (bsi.block_len) {
10157 ret = btrfs_add_swap_extent(sis, &bsi);
10162 bsi.block_start = physical_block_start;
10163 bsi.block_len = len;
10170 ret = btrfs_add_swap_extent(sis, &bsi);
10173 if (!IS_ERR_OR_NULL(em))
10174 free_extent_map(em);
10176 unlock_extent_cached(io_tree, 0, isize - 1, &cached_state);
10179 btrfs_swap_deactivate(file);
10181 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
10187 sis->bdev = device->bdev;
10188 *span = bsi.highest_ppage - bsi.lowest_ppage + 1;
10189 sis->max = bsi.nr_pages;
10190 sis->pages = bsi.nr_pages - 1;
10191 sis->highest_bit = bsi.nr_pages - 1;
10192 return bsi.nr_extents;
10195 static void btrfs_swap_deactivate(struct file *file)
10199 static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
10202 return -EOPNOTSUPP;
10206 static const struct inode_operations btrfs_dir_inode_operations = {
10207 .getattr = btrfs_getattr,
10208 .lookup = btrfs_lookup,
10209 .create = btrfs_create,
10210 .unlink = btrfs_unlink,
10211 .link = btrfs_link,
10212 .mkdir = btrfs_mkdir,
10213 .rmdir = btrfs_rmdir,
10214 .rename = btrfs_rename2,
10215 .symlink = btrfs_symlink,
10216 .setattr = btrfs_setattr,
10217 .mknod = btrfs_mknod,
10218 .listxattr = btrfs_listxattr,
10219 .permission = btrfs_permission,
10220 .get_acl = btrfs_get_acl,
10221 .set_acl = btrfs_set_acl,
10222 .update_time = btrfs_update_time,
10223 .tmpfile = btrfs_tmpfile,
10226 static const struct file_operations btrfs_dir_file_operations = {
10227 .llseek = generic_file_llseek,
10228 .read = generic_read_dir,
10229 .iterate_shared = btrfs_real_readdir,
10230 .open = btrfs_opendir,
10231 .unlocked_ioctl = btrfs_ioctl,
10232 #ifdef CONFIG_COMPAT
10233 .compat_ioctl = btrfs_compat_ioctl,
10235 .release = btrfs_release_file,
10236 .fsync = btrfs_sync_file,
10239 static const struct extent_io_ops btrfs_extent_io_ops = {
10240 /* mandatory callbacks */
10241 .submit_bio_hook = btrfs_submit_bio_hook,
10242 .readpage_end_io_hook = btrfs_readpage_end_io_hook,
10246 * btrfs doesn't support the bmap operation because swapfiles
10247 * use bmap to make a mapping of extents in the file. They assume
10248 * these extents won't change over the life of the file and they
10249 * use the bmap result to do IO directly to the drive.
10251 * the btrfs bmap call would return logical addresses that aren't
10252 * suitable for IO and they also will change frequently as COW
10253 * operations happen. So, swapfile + btrfs == corruption.
10255 * For now we're avoiding this by dropping bmap.
10257 static const struct address_space_operations btrfs_aops = {
10258 .readpage = btrfs_readpage,
10259 .writepage = btrfs_writepage,
10260 .writepages = btrfs_writepages,
10261 .readpages = btrfs_readpages,
10262 .direct_IO = btrfs_direct_IO,
10263 .invalidatepage = btrfs_invalidatepage,
10264 .releasepage = btrfs_releasepage,
10265 #ifdef CONFIG_MIGRATION
10266 .migratepage = btrfs_migratepage,
10268 .set_page_dirty = btrfs_set_page_dirty,
10269 .error_remove_page = generic_error_remove_page,
10270 .swap_activate = btrfs_swap_activate,
10271 .swap_deactivate = btrfs_swap_deactivate,
10274 static const struct inode_operations btrfs_file_inode_operations = {
10275 .getattr = btrfs_getattr,
10276 .setattr = btrfs_setattr,
10277 .listxattr = btrfs_listxattr,
10278 .permission = btrfs_permission,
10279 .fiemap = btrfs_fiemap,
10280 .get_acl = btrfs_get_acl,
10281 .set_acl = btrfs_set_acl,
10282 .update_time = btrfs_update_time,
10284 static const struct inode_operations btrfs_special_inode_operations = {
10285 .getattr = btrfs_getattr,
10286 .setattr = btrfs_setattr,
10287 .permission = btrfs_permission,
10288 .listxattr = btrfs_listxattr,
10289 .get_acl = btrfs_get_acl,
10290 .set_acl = btrfs_set_acl,
10291 .update_time = btrfs_update_time,
10293 static const struct inode_operations btrfs_symlink_inode_operations = {
10294 .get_link = page_get_link,
10295 .getattr = btrfs_getattr,
10296 .setattr = btrfs_setattr,
10297 .permission = btrfs_permission,
10298 .listxattr = btrfs_listxattr,
10299 .update_time = btrfs_update_time,
10302 const struct dentry_operations btrfs_dentry_operations = {
10303 .d_delete = btrfs_dentry_delete,