From: Filipe Manana <fdmanana@xxxxxxxx> If we create a symlink, fsync its parent directory, crash/power fail and mount the filesystem, we end up with an empty symlink, which not only is useless it's also not allowed in linux (the man page symlink(2) is well explicit about that). So we just need to make sure to fully log an inode if it's a symlink, to ensure its inline extent gets logged, ensuring the same behaviour as ext3, ext4, xfs, reiserfs, f2fs, nilfs2, etc. Example reproducer: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ mkdir /mnt/testdir $ sync $ ln -s /mnt/foo /mnt/testdir/bar $ xfs_io -c fsync /mnt/testdir <power fail> $ mount /dev/sdb /mnt $ readlink /mnt/testdir/bar <empty string> A test case for fstests follows soon. Signed-off-by: Filipe Manana <fdmanana@xxxxxxxx> --- fs/btrfs/tree-log.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 4709932..a24a0ba 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -5158,7 +5158,7 @@ process_leaf: } ctx->log_new_dentries = false; - if (type == BTRFS_FT_DIR) + if (type == BTRFS_FT_DIR || type == BTRFS_FT_SYMLINK) log_mode = LOG_INODE_ALL; btrfs_release_path(path); ret = btrfs_log_inode(trans, root, di_inode, -- 2.7.0.rc3 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
