Btrfs: Check INCOMPAT flags on remount and add helper function

In support of the recently added capability to remount with lzo
compression, provide a helper function to check the compression
INCOMPAT flags when remounting with lzo compression, and set
the flags if necessary.

Also, implement the new helper function when defragmenting with
explicit lzo compression and when setting the default subvolume.

Signed-off-by: Mitch Harder <mitch.harder@sabayonlinux.org>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 26da344231ac..75ee2c7791f0 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -401,6 +401,7 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
                                 compress_type = "lzo";
                                 info->compress_type = BTRFS_COMPRESS_LZO;
                                 btrfs_set_opt(info->mount_opt, COMPRESS);
+                                btrfs_set_fs_incompat(info, COMPRESS_LZO);
                         } else if (strncmp(args[0].from, "no", 2) == 0) {
                                 compress_type = "no";
                                 info->compress_type = BTRFS_COMPRESS_NONE;