From 3d850dd44889d3aa67d0b8007c2cdd259bff7da4 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Thu, 12 Mar 2015 23:23:13 +0000 Subject: [PATCH] Btrfs: add missing inode item update in fallocate() If we fallocate(), without the keep size flag, into an area already covered by an extent previously fallocated, we were updating the inode's i_size but we weren't updating the inode item in the fs/subvol tree. A following umount + mount would result in a loss of the inode's size (and an fsync would miss too the fact that the inode changed). Reproducer: $ mkfs.btrfs -f /dev/sdd $ mount /dev/sdd /mnt $ fallocate -n -l 1M /mnt/foobar $ fallocate -l 512K /mnt/foobar $ umount /mnt $ mount /dev/sdd /mnt $ od -t x1 /mnt/foobar 0000000 The expected result is: $ od -t x1 /mnt/foobar 0000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 * 2000000 A test case for fstests follows soon. Signed-off-by: Filipe Manana Reviewed-by: Liu Bo Signed-off-by: Chris Mason --- fs/btrfs/file.c | 29 ++++++++++++++++++++--------- 1 file changed, 20 insertions(+), 9 deletions(-) diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 7d4bb3b6fbc2..150db5e50c2d 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -2669,23 +2669,34 @@ static long btrfs_fallocate(struct file *file, int mode, 1 << inode->i_blkbits, offset + len, &alloc_hint); - - if (ret < 0) { - free_extent_map(em); - break; - } } else if (actual_end > inode->i_size && !(mode & FALLOC_FL_KEEP_SIZE)) { + struct btrfs_trans_handle *trans; + /* * We didn't need to allocate any more space, but we * still extended the size of the file so we need to - * update i_size. + * update i_size and the inode item. */ - inode->i_ctime = CURRENT_TIME; - i_size_write(inode, actual_end); - btrfs_ordered_update_i_size(inode, actual_end, NULL); + trans = btrfs_start_transaction(root, 1); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + } else { + inode->i_ctime = CURRENT_TIME; + i_size_write(inode, actual_end); + btrfs_ordered_update_i_size(inode, actual_end, + NULL); + ret = btrfs_update_inode(trans, root, inode); + if (ret) + btrfs_end_transaction(trans, root); + else + ret = btrfs_end_transaction(trans, + root); + } } free_extent_map(em); + if (ret < 0) + break; cur_offset = last_byte; if (cur_offset >= alloc_end) { -- 2.34.1