[PATCH v2 10/13] btrfs: btrfs: untagle if else maze in btrfs_map_block

[Johannes Thumshirn]

Untangle the if-else maze in btrfs_map_block into a switch statement,
checking the different block-group profile types and call out into the
per-profile block mapping helpers.

Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
---
 fs/btrfs/volumes.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index e23c7d2842a6..efb31c3005b7 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6578,28 +6578,38 @@ int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
 	if (!dev_replace_is_ongoing)
 		up_read(&dev_replace->rwsem);
 
-	if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
+	switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
+	case BTRFS_BLOCK_GROUP_RAID0:
 		map_blocks_raid0(map, &io_geom);
-	} else if (map->type & BTRFS_BLOCK_GROUP_RAID1_MASK) {
+		break;
+	case BTRFS_BLOCK_GROUP_RAID1:
+	case BTRFS_BLOCK_GROUP_RAID1C3:
+	case BTRFS_BLOCK_GROUP_RAID1C4:
 		map_blocks_raid1(fs_info, map, &io_geom,
 				 dev_replace_is_ongoing);
-	} else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
+		break;
+	case BTRFS_BLOCK_GROUP_DUP:
 		map_blocks_dup(map, &io_geom);
-	} else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
+		break;
+	case BTRFS_BLOCK_GROUP_RAID10:
 		map_blocks_raid10(fs_info, map, &io_geom,
 				  dev_replace_is_ongoing);
-	} else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
+		break;
+	case BTRFS_BLOCK_GROUP_RAID5:
+	case BTRFS_BLOCK_GROUP_RAID6:
 		if (op != BTRFS_MAP_READ || io_geom.mirror_num > 1)
 			map_blocks_raid56_write(map, &io_geom, logical, length);
 		else
 			map_blocks_raid56_read(map, &io_geom);
-	} else {
+		break;
+	default:
 		/*
 		 * After this, stripe_nr is the number of stripes on this
 		 * device we have to walk to find the data, and stripe_index is
 		 * the number of our device in the stripe array
 		 */
 		map_blocks_single(map, &io_geom);
+		break;
 	}
 	if (io_geom.stripe_index >= map->num_stripes) {
 		btrfs_crit(fs_info,

-- 
2.43.0