diff options
| -rw-r--r-- | fs/btrfs/extent_io.c | 36 | ||||
| -rw-r--r-- | fs/btrfs/inode.c | 7 | ||||
| -rw-r--r-- | fs/btrfs/tests/extent-io-tests.c | 12 |
3 files changed, 40 insertions, 15 deletions
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 18ef234fe3dc..d022654af420 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -1975,10 +1975,18 @@ static noinline int lock_delalloc_pages(struct inode *inode, /* * Find and lock a contiguous range of bytes in the file marked as delalloc, no - * more than @max_bytes. @Start and @end are used to return the range, + * more than @max_bytes. * - * Return: true if we find something - * false if nothing was in the tree + * @start: The original start bytenr to search. + * Will store the extent range start bytenr. + * @end: The original end bytenr of the search range + * Will store the extent range end bytenr. + * + * Return true if we find a delalloc range which starts inside the original + * range, and @start/@end will store the delalloc range start/end. + * + * Return false if we can't find any delalloc range which starts inside the + * original range, and @start/@end will be the non-delalloc range start/end. */ EXPORT_FOR_TESTS noinline_for_stack bool find_lock_delalloc_range(struct inode *inode, @@ -1986,6 +1994,8 @@ noinline_for_stack bool find_lock_delalloc_range(struct inode *inode, u64 *end) { struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree; + const u64 orig_start = *start; + const u64 orig_end = *end; u64 max_bytes = BTRFS_MAX_EXTENT_SIZE; u64 delalloc_start; u64 delalloc_end; @@ -1994,15 +2004,23 @@ noinline_for_stack bool find_lock_delalloc_range(struct inode *inode, int ret; int loops = 0; + /* Caller should pass a valid @end to indicate the search range end */ + ASSERT(orig_end > orig_start); + + /* The range should at least cover part of the page */ + ASSERT(!(orig_start >= page_offset(locked_page) + PAGE_SIZE || + orig_end <= page_offset(locked_page))); again: /* step one, find a bunch of delalloc bytes starting at start */ delalloc_start = *start; delalloc_end = 0; found = btrfs_find_delalloc_range(tree, &delalloc_start, &delalloc_end, max_bytes, &cached_state); - if (!found || delalloc_end <= *start) { + if (!found || delalloc_end <= *start || delalloc_start > orig_end) { *start = delalloc_start; - *end = delalloc_end; + + /* @delalloc_end can be -1, never go beyond @orig_end */ + *end = min(delalloc_end, orig_end); free_extent_state(cached_state); return false; } @@ -3771,16 +3789,16 @@ static noinline_for_stack int writepage_delalloc(struct btrfs_inode *inode, struct page *page, struct writeback_control *wbc, unsigned long *nr_written) { - u64 page_end = page_offset(page) + PAGE_SIZE - 1; - bool found; + const u64 page_end = page_offset(page) + PAGE_SIZE - 1; u64 delalloc_start = page_offset(page); u64 delalloc_to_write = 0; - u64 delalloc_end = 0; int ret; int page_started = 0; + while (delalloc_start < page_end) { + u64 delalloc_end = page_end; + bool found; - while (delalloc_end < page_end) { found = find_lock_delalloc_range(&inode->vfs_inode, page, &delalloc_start, &delalloc_end); diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 57a2bc25b4d2..0276fa951641 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1955,6 +1955,13 @@ int btrfs_run_delalloc_range(struct btrfs_inode *inode, struct page *locked_page int ret; const bool zoned = btrfs_is_zoned(inode->root->fs_info); + /* + * The range must cover part of the @locked_page, or the returned + * @page_started can confuse the caller. + */ + ASSERT(!(end <= page_offset(locked_page) || + start >= page_offset(locked_page) + PAGE_SIZE)); + if (should_nocow(inode, start, end)) { /* * Normally on a zoned device we're only doing COW writes, but diff --git a/fs/btrfs/tests/extent-io-tests.c b/fs/btrfs/tests/extent-io-tests.c index 73e96d505f4f..c2e72e7a8ff0 100644 --- a/fs/btrfs/tests/extent-io-tests.c +++ b/fs/btrfs/tests/extent-io-tests.c @@ -112,7 +112,7 @@ static int test_find_delalloc(u32 sectorsize) */ set_extent_delalloc(tmp, 0, sectorsize - 1, 0, NULL); start = 0; - end = 0; + end = start + PAGE_SIZE - 1; found = find_lock_delalloc_range(inode, locked_page, &start, &end); if (!found) { @@ -143,7 +143,7 @@ static int test_find_delalloc(u32 sectorsize) } set_extent_delalloc(tmp, sectorsize, max_bytes - 1, 0, NULL); start = test_start; - end = 0; + end = start + PAGE_SIZE - 1; found = find_lock_delalloc_range(inode, locked_page, &start, &end); if (!found) { @@ -177,14 +177,14 @@ static int test_find_delalloc(u32 sectorsize) goto out_bits; } start = test_start; - end = 0; + end = start + PAGE_SIZE - 1; found = find_lock_delalloc_range(inode, locked_page, &start, &end); if (found) { test_err("found range when we shouldn't have"); goto out_bits; } - if (end != (u64)-1) { + if (end != test_start + PAGE_SIZE - 1) { test_err("did not return the proper end offset"); goto out_bits; } @@ -198,7 +198,7 @@ static int test_find_delalloc(u32 sectorsize) */ set_extent_delalloc(tmp, max_bytes, total_dirty - 1, 0, NULL); start = test_start; - end = 0; + end = start + PAGE_SIZE - 1; found = find_lock_delalloc_range(inode, locked_page, &start, &end); if (!found) { @@ -233,7 +233,7 @@ static int test_find_delalloc(u32 sectorsize) /* We unlocked it in the previous test */ lock_page(locked_page); start = test_start; - end = 0; + end = start + PAGE_SIZE - 1; /* * Currently if we fail to find dirty pages in the delalloc range we * will adjust max_bytes down to PAGE_SIZE and then re-search. If |