X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=volumes.h;h=5bcaae7f03d2ef54d249ec0efbd179b049b1f755;hb=30b852cd7e2299ba7795cd302d783724d88e101f;hp=bc3516aa3d782aca029f891720a82a146901cedb;hpb=12becfe1220bb4e45e529d4d2363394431605deb;p=platform%2Fupstream%2Fbtrfs-progs.git

diff --git a/volumes.h b/volumes.h
index bc3516a..5bcaae7 100644
--- a/volumes.h
+++ b/volumes.h
@@ -209,6 +209,28 @@ static inline int check_crossing_stripes(struct btrfs_fs_info *fs_info,
 		(bg_offset + len - 1) / BTRFS_STRIPE_LEN);
 }
 
+static inline u64 calc_stripe_length(u64 type, u64 length, int num_stripes)
+{
+	u64 stripe_size;
+
+	if (type & BTRFS_BLOCK_GROUP_RAID0) {
+		stripe_size = length;
+		stripe_size /= num_stripes;
+	} else if (type & BTRFS_BLOCK_GROUP_RAID10) {
+		stripe_size = length * 2;
+		stripe_size /= num_stripes;
+	} else if (type & BTRFS_BLOCK_GROUP_RAID5) {
+		stripe_size = length;
+		stripe_size /= (num_stripes - 1);
+	} else if (type & BTRFS_BLOCK_GROUP_RAID6) {
+		stripe_size = length;
+		stripe_size /= (num_stripes - 2);
+	} else {
+		stripe_size = length;
+	}
+	return stripe_size;
+}
+
 int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 		      u64 logical, u64 *length, u64 *type,
 		      struct btrfs_multi_bio **multi_ret, int mirror_num,