Btrfs: Introduce BTRFS_BLOCK_GROUP_RAID56_MASK to check raid56 simply

So we can check raid56 with:
 (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
instead of long:
 (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6))

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 19781e9..1ae527c 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -1273,7 +1273,7 @@
 {
 	int i;
 
-	if (map_type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) {
+	if (map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
 		/* RAID5/6 */
 		for (i = 0; i < nstripes; i++) {
 			if (raid_map[i] == RAID6_Q_STRIPE ||
@@ -1420,8 +1420,7 @@
 static inline int scrub_is_page_on_raid56(struct scrub_page *page)
 {
 	return page->recover &&
-	       (page->recover->bbio->map_type & (BTRFS_BLOCK_GROUP_RAID5 |
-	       BTRFS_BLOCK_GROUP_RAID6));
+	       (page->recover->bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK);
 }
 
 static int scrub_submit_raid56_bio_wait(struct btrfs_fs_info *fs_info,
@@ -2994,8 +2993,7 @@
 	} else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
 		increment = map->stripe_len;
 		mirror_num = num % map->num_stripes + 1;
-	} else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
-				BTRFS_BLOCK_GROUP_RAID6)) {
+	} else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
 		get_raid56_logic_offset(physical, num, map, &offset, NULL);
 		increment = map->stripe_len * nr_data_stripes(map);
 		mirror_num = 1;
@@ -3029,8 +3027,7 @@
 	 */
 	logical = base + offset;
 	physical_end = physical + nstripes * map->stripe_len;
-	if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
-			 BTRFS_BLOCK_GROUP_RAID6)) {
+	if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
 		get_raid56_logic_offset(physical_end, num,
 					map, &logic_end, NULL);
 		logic_end += base;
@@ -3076,8 +3073,7 @@
 	ret = 0;
 	while (physical < physical_end) {
 		/* for raid56, we skip parity stripe */
-		if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
-				BTRFS_BLOCK_GROUP_RAID6)) {
+		if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
 			ret = get_raid56_logic_offset(physical, num,
 					map, &logical, &stripe_logical);
 			logical += base;
@@ -3235,8 +3231,7 @@
 			scrub_free_csums(sctx);
 			if (extent_logical + extent_len <
 			    key.objectid + bytes) {
-				if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
-					BTRFS_BLOCK_GROUP_RAID6)) {
+				if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
 					/*
 					 * loop until we find next data stripe
 					 * or we have finished all stripes.