diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 6d19a0a..7bb2869 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -238,7 +238,7 @@
 	return em;
 }
 
-u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
+u32 btrfs_csum_data(char *data, u32 seed, size_t len)
 {
 	return crc32c(seed, data, len);
 }
@@ -274,7 +274,7 @@
 		if (err)
 			return 1;
 		cur_len = min(len, map_len - (offset - map_start));
-		crc = btrfs_csum_data(root, kaddr + offset - map_start,
+		crc = btrfs_csum_data(kaddr + offset - map_start,
 				      crc, cur_len);
 		len -= cur_len;
 		offset += cur_len;
@@ -2919,7 +2919,7 @@
 			btrfs_set_super_bytenr(sb, bytenr);
 
 			crc = ~(u32)0;
-			crc = btrfs_csum_data(NULL, (char *)sb +
+			crc = btrfs_csum_data((char *)sb +
 					      BTRFS_CSUM_SIZE, crc,
 					      BTRFS_SUPER_INFO_SIZE -
 					      BTRFS_CSUM_SIZE);