Btrfs: make raid attr array more readable

The current code of raid attr arry is hard to understand and it is easy to
introduce some problem if we modify the array. So I changed it and made it
more readable.

Cc: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

1 files changed, 9 insertions, 1 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 9ee099f3f834..541ce9a9949e 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -953,7 +953,15 @@ struct btrfs_dev_replace_item {
 #define BTRFS_BLOCK_GROUP_DUP           (1ULL << 5)
 #define BTRFS_BLOCK_GROUP_RAID10        (1ULL << 6)
 #define BTRFS_BLOCK_GROUP_RESERVED      BTRFS_AVAIL_ALLOC_BIT_SINGLE
-#define BTRFS_NR_RAID_TYPES             5
+
+enum btrfs_raid_types {
+        BTRFS_RAID_RAID10,
+        BTRFS_RAID_RAID1,
+        BTRFS_RAID_DUP,
+        BTRFS_RAID_RAID0,
+        BTRFS_RAID_SINGLE,
+        BTRFS_NR_RAID_TYPES
+};
 
 #define BTRFS_BLOCK_GROUP_TYPE_MASK     (BTRFS_BLOCK_GROUP_DATA |    \
                                          BTRFS_BLOCK_GROUP_SYSTEM |  \