In case of subpage-blocksize, the file blocks to be punched may map only part of a page. For file blocks inside such pages, we need to check for the presence of BLK_STATE_UPTODATE flag.
Signed-off-by: Chandan Rajendra <chan...@linux.vnet.ibm.com> --- fs/btrfs/file.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 88 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 54602e6..6490e56 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -2350,6 +2350,8 @@ static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len) struct btrfs_path *path; struct btrfs_block_rsv *rsv; struct btrfs_trans_handle *trans; + struct address_space *mapping = inode->i_mapping; + pgoff_t start_index, end_index; u64 lockstart; u64 lockend; u64 tail_start; @@ -2362,6 +2364,7 @@ static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len) int err = 0; unsigned int rsv_count; bool same_block; + bool same_page; bool no_holes = btrfs_fs_incompat(root->fs_info, NO_HOLES); u64 ino_size; bool truncated_block = false; @@ -2458,11 +2461,45 @@ static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len) goto out_only_mutex; } + start_index = lockstart >> PAGE_SHIFT; + end_index = lockend >> PAGE_SHIFT; + + same_page = lockstart >> PAGE_SHIFT + == lockend >> PAGE_SHIFT; + while (1) { struct btrfs_ordered_extent *ordered; + struct page *start_page = NULL; + struct page *end_page = NULL; + u64 nr_pages; + int start_page_blks_uptodate; + int end_page_blks_uptodate; truncate_pagecache_range(inode, lockstart, lockend); + if (lockstart & (PAGE_SIZE - 1)) { + start_page = find_or_create_page(mapping, start_index, + GFP_NOFS); + if (!start_page) { + inode_unlock(inode); + return -ENOMEM; + } + } + + if (!same_page && ((lockend + 1) & (PAGE_SIZE - 1))) { + end_page = find_or_create_page(mapping, end_index, + GFP_NOFS); + if (!end_page) { + if (start_page) { + unlock_page(start_page); + put_page(start_page); + } + inode_unlock(inode); + return -ENOMEM; + } + } + + lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, &cached_state); ordered = btrfs_lookup_first_ordered_extent(inode, lockend); @@ -2472,18 +2509,68 @@ static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len) * and nobody raced in and read a page in this range, if we did * we need to try again. */ + nr_pages = round_up(lockend, PAGE_SIZE) + - round_down(lockstart, PAGE_SIZE); + nr_pages >>= PAGE_SHIFT; + + start_page_blks_uptodate = 0; + end_page_blks_uptodate = 0; + if (root->sectorsize < PAGE_SIZE) { + u64 page_end; + + page_end = round_down(lockstart, PAGE_SIZE) + + PAGE_SIZE - 1; + page_end = min(page_end, lockend); + if (start_page + && PagePrivate(start_page) + && test_page_blks_state(start_page, 1 << BLK_STATE_UPTODATE, + lockstart, page_end, 0)) + start_page_blks_uptodate = 1; + if (end_page + && PagePrivate(end_page) + && test_page_blks_state(end_page, 1 << BLK_STATE_UPTODATE, + page_offset(end_page), lockend, 0)) + end_page_blks_uptodate = 1; + } else { + if (start_page && PagePrivate(start_page) + && PageUptodate(start_page)) + start_page_blks_uptodate = 1; + if (end_page && PagePrivate(end_page) + && PageUptodate(end_page)) + end_page_blks_uptodate = 1; + } + if ((!ordered || (ordered->file_offset + ordered->len <= lockstart || ordered->file_offset > lockend)) && - !btrfs_page_exists_in_range(inode, lockstart, lockend)) { + (!start_page_blks_uptodate && !end_page_blks_uptodate && + !(nr_pages > 2 && btrfs_page_exists_in_range(inode, + round_up(lockstart, PAGE_SIZE), + round_down(lockend, PAGE_SIZE) - 1)))) { if (ordered) btrfs_put_ordered_extent(ordered); + if (end_page) { + unlock_page(end_page); + put_page(end_page); + } + if (start_page) { + unlock_page(start_page); + put_page(start_page); + } break; } if (ordered) btrfs_put_ordered_extent(ordered); unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, &cached_state, GFP_NOFS); + if (end_page) { + unlock_page(end_page); + put_page(end_page); + } + if (start_page) { + unlock_page(start_page); + put_page(start_page); + } ret = btrfs_wait_ordered_range(inode, lockstart, lockend - lockstart + 1); if (ret) { -- 2.5.5 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html