diff --git a/include/bb_e2fs_defs.h b/include/bb_e2fs_defs.h
index 7974497ca..071c660c5 100644
--- a/include/bb_e2fs_defs.h
+++ b/include/bb_e2fs_defs.h
@@ -463,6 +463,7 @@ struct ext2_super_block {
 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask)			\
 	( EXT2_SB(sb)->s_feature_incompat & (mask) )
 
+/* for s_feature_compat */
 #define EXT2_FEATURE_COMPAT_DIR_PREALLOC	0x0001
 #define EXT2_FEATURE_COMPAT_IMAGIC_INODES	0x0002
 #define EXT3_FEATURE_COMPAT_HAS_JOURNAL		0x0004
@@ -470,23 +471,45 @@ struct ext2_super_block {
 #define EXT2_FEATURE_COMPAT_RESIZE_INO		0x0010
 #define EXT2_FEATURE_COMPAT_DIR_INDEX		0x0020
 
+/* for s_feature_ro_compat */
 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
 #define EXT2_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
-/* #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR	0x0004 not used */
+#define EXT2_FEATURE_RO_COMPAT_BTREE_DIR	0x0004 /* not used */
+#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE	0x0008
+#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
+#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
+#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
 
+/* for s_feature_incompat */
 #define EXT2_FEATURE_INCOMPAT_COMPRESSION	0x0001
 #define EXT2_FEATURE_INCOMPAT_FILETYPE		0x0002
-#define EXT3_FEATURE_INCOMPAT_RECOVER		0x0004 /* Needs recovery */
-#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008 /* Journal device */
+#define EXT3_FEATURE_INCOMPAT_RECOVER		0x0004
+#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008
 #define EXT2_FEATURE_INCOMPAT_META_BG		0x0010
-#define EXT3_FEATURE_INCOMPAT_EXTENTS		0x0040
+#define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040
+#define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
+#define EXT4_FEATURE_INCOMPAT_MMP		0x0100
+#define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
 
 
 #define EXT2_FEATURE_COMPAT_SUPP	0
-#define EXT2_FEATURE_INCOMPAT_SUPP	(EXT2_FEATURE_INCOMPAT_FILETYPE)
 #define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
 					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
 					 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
+#define EXT2_FEATURE_INCOMPAT_SUPP	(EXT2_FEATURE_INCOMPAT_FILETYPE| \
+					 EXT2_FEATURE_INCOMPAT_META_BG)
+#define EXT2_FEATURE_INCOMPAT_UNSUPPORTED	(~EXT2_FEATURE_INCOMPAT_SUPP)
+#define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED	(~EXT2_FEATURE_RO_COMPAT_SUPP)
+
+#define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
+					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
+					 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
+#define EXT3_FEATURE_INCOMPAT_SUPP	(EXT2_FEATURE_INCOMPAT_FILETYPE| \
+					 EXT3_FEATURE_INCOMPAT_RECOVER| \
+					 EXT2_FEATURE_INCOMPAT_META_BG)
+#define EXT3_FEATURE_INCOMPAT_UNSUPPORTED	(~EXT3_FEATURE_INCOMPAT_SUPP)
+#define EXT3_FEATURE_RO_COMPAT_UNSUPPORTED	(~EXT3_FEATURE_RO_COMPAT_SUPP)
+
 
 /*
  * Default values for user and/or group using reserved blocks
diff --git a/util-linux/volume_id/ext.c b/util-linux/volume_id/ext.c
index aa23d1ebf..97451067f 100644
--- a/util-linux/volume_id/ext.c
+++ b/util-linux/volume_id/ext.c
@@ -19,70 +19,10 @@
  */
 
 #include "volume_id_internal.h"
-
-struct ext2_super_block {
-	uint32_t	inodes_count;
-	uint32_t	blocks_count;
-	uint32_t	r_blocks_count;
-	uint32_t	free_blocks_count;
-	uint32_t	free_inodes_count;
-	uint32_t	first_data_block;
-	uint32_t	log_block_size;
-	uint32_t	dummy3[7];
-	uint8_t	magic[2];
-	uint16_t	state;
-	uint32_t	dummy5[8];
-	uint32_t	feature_compat;
-	uint32_t	feature_incompat;
-	uint32_t	feature_ro_compat;
-	uint8_t	uuid[16];
-	uint8_t	volume_name[16];
-} PACKED;
+#include "bb_e2fs_defs.h"
 
 #define EXT_SUPERBLOCK_OFFSET			0x400
 
-/* for s_flags */
-#define EXT2_FLAGS_TEST_FILESYS			0x0004
-
-/* for s_feature_compat */
-#define EXT3_FEATURE_COMPAT_HAS_JOURNAL		0x0004
-
-/* for s_feature_ro_compat */
-#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
-#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE	0x0002
-#define EXT2_FEATURE_RO_COMPAT_BTREE_DIR	0x0004
-#define EXT4_FEATURE_RO_COMPAT_HUGE_FILE	0x0008
-#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM		0x0010
-#define EXT4_FEATURE_RO_COMPAT_DIR_NLINK	0x0020
-#define EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE	0x0040
-
-/* for s_feature_incompat */
-#define EXT2_FEATURE_INCOMPAT_FILETYPE		0x0002
-#define EXT3_FEATURE_INCOMPAT_RECOVER		0x0004
-#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008
-#define EXT2_FEATURE_INCOMPAT_META_BG		0x0010
-#define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
-#define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
-#define EXT4_FEATURE_INCOMPAT_MMP		0x0100
-#define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
-
-#define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
-					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
-					 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
-#define EXT2_FEATURE_INCOMPAT_SUPP	(EXT2_FEATURE_INCOMPAT_FILETYPE| \
-					 EXT2_FEATURE_INCOMPAT_META_BG)
-#define EXT2_FEATURE_INCOMPAT_UNSUPPORTED	~EXT2_FEATURE_INCOMPAT_SUPP
-#define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED	~EXT2_FEATURE_RO_COMPAT_SUPP
-
-#define EXT3_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
-					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
-					 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
-#define EXT3_FEATURE_INCOMPAT_SUPP	(EXT2_FEATURE_INCOMPAT_FILETYPE| \
-					 EXT3_FEATURE_INCOMPAT_RECOVER| \
-					 EXT2_FEATURE_INCOMPAT_META_BG)
-#define EXT3_FEATURE_INCOMPAT_UNSUPPORTED	~EXT3_FEATURE_INCOMPAT_SUPP
-#define EXT3_FEATURE_RO_COMPAT_UNSUPPORTED	~EXT3_FEATURE_RO_COMPAT_SUPP
-
 int FAST_FUNC volume_id_probe_ext(struct volume_id *id /*,uint64_t off*/)
 {
 #define off ((uint64_t)0)
@@ -94,24 +34,24 @@ int FAST_FUNC volume_id_probe_ext(struct volume_id *id /*,uint64_t off*/)
 	if (es == NULL)
 		return -1;
 
-	if (es->magic[0] != 0123 || es->magic[1] != 0357) {
+	if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
 		dbg("ext: no magic found");
 		return -1;
 	}
 
 //	volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
 //	volume_id_set_label_raw(id, es->volume_name, 16);
-	volume_id_set_label_string(id, es->volume_name, 16);
-	volume_id_set_uuid(id, es->uuid, UUID_DCE);
+	volume_id_set_label_string(id, (void*)es->s_volume_name, 16);
+	volume_id_set_uuid(id, es->s_uuid, UUID_DCE);
 	dbg("ext: label '%s' uuid '%s'", id->label, id->uuid);
 
 #if ENABLE_FEATURE_BLKID_TYPE
-	if ((es->feature_ro_compat & cpu_to_le32(EXT4_FEATURE_RO_COMPAT_HUGE_FILE | EXT4_FEATURE_RO_COMPAT_DIR_NLINK))
-	 || (es->feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_EXTENTS | EXT4_FEATURE_INCOMPAT_64BIT))
+	if ((es->s_feature_ro_compat & cpu_to_le32(EXT4_FEATURE_RO_COMPAT_HUGE_FILE | EXT4_FEATURE_RO_COMPAT_DIR_NLINK))
+	 || (es->s_feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_EXTENTS | EXT4_FEATURE_INCOMPAT_64BIT))
 	) {
 		id->type = "ext4";
 	}
-	else if (es->feature_compat & cpu_to_le32(EXT3_FEATURE_COMPAT_HAS_JOURNAL))
+	else if (es->s_feature_compat & cpu_to_le32(EXT3_FEATURE_COMPAT_HAS_JOURNAL))
 		id->type = "ext3";
 	else
 		id->type = "ext2";