diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 7e68673..3f745fb 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -621,13 +621,13 @@
 {
 	int i;
 	struct ext2_sb_info *sbi = EXT2_SB(sb);
-	unsigned long first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
-	unsigned long last_block;
 
 	ext2_debug ("Checking group descriptors");
 
 	for (i = 0; i < sbi->s_groups_count; i++) {
 		struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
+		ext2_fsblk_t first_block = ext2_group_first_block_no(sb, i);
+		ext2_fsblk_t last_block;
 
 		if (i == sbi->s_groups_count - 1)
 			last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
@@ -663,7 +663,6 @@
 				    i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
 			return 0;
 		}
-		first_block += EXT2_BLOCKS_PER_GROUP(sb);
 	}
 	return 1;
 }
@@ -720,10 +719,9 @@
 				    int nr)
 {
 	struct ext2_sb_info *sbi = EXT2_SB(sb);
-	unsigned long bg, first_data_block, first_meta_bg;
+	unsigned long bg, first_meta_bg;
 	int has_super = 0;
 	
-	first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block);
 	first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
 
 	if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
@@ -732,7 +730,8 @@
 	bg = sbi->s_desc_per_block * nr;
 	if (ext2_bg_has_super(sb, bg))
 		has_super = 1;
-	return (first_data_block + has_super + (bg * sbi->s_blocks_per_group));
+
+	return ext2_group_first_block_no(sb, bg) + has_super;
 }
 
 static int ext2_fill_super(struct super_block *sb, void *data, int silent)