+/*
+ * In directories inode numbers are stored as unaligned arrays of unsigned
+ * 8bit integers on disk.
+ *
+ * For v1 directories or v2 directories that contain inode numbers that
+ * do not fit into 32bit the array has eight members, but the first member
+ * is always zero:
+ *
+ * |unused|48-55|40-47|32-39|24-31|16-23| 8-15| 0- 7|
+ *
+ * For v2 directories that only contain entries with inode numbers that fit
+ * into 32bits a four-member array is used:
+ *
+ * |24-31|16-23| 8-15| 0- 7|
+ */
+
+#define XFS_GET_DIR_INO4(di) \
+ (((__u32)(di).i[0] << 24) | ((di).i[1] << 16) | ((di).i[2] << 8) | ((di).i[3]))
+
+#define XFS_PUT_DIR_INO4(from, di) \
+do { \
+ (di).i[0] = (((from) & 0xff000000ULL) >> 24); \
+ (di).i[1] = (((from) & 0x00ff0000ULL) >> 16); \
+ (di).i[2] = (((from) & 0x0000ff00ULL) >> 8); \
+ (di).i[3] = ((from) & 0x000000ffULL); \
+} while (0)
+
+#define XFS_DI_HI(di) \
+ (((__u32)(di).i[1] << 16) | ((di).i[2] << 8) | ((di).i[3]))
+#define XFS_DI_LO(di) \
+ (((__u32)(di).i[4] << 24) | ((di).i[5] << 16) | ((di).i[6] << 8) | ((di).i[7]))
+
+#define XFS_GET_DIR_INO8(di) \
+ (((xfs_ino_t)XFS_DI_LO(di) & 0xffffffffULL) | \
+ ((xfs_ino_t)XFS_DI_HI(di) << 32))
+
+#define XFS_PUT_DIR_INO8(from, di) \
+do { \
+ (di).i[0] = 0; \
+ (di).i[1] = (((from) & 0x00ff000000000000ULL) >> 48); \
+ (di).i[2] = (((from) & 0x0000ff0000000000ULL) >> 40); \
+ (di).i[3] = (((from) & 0x000000ff00000000ULL) >> 32); \
+ (di).i[4] = (((from) & 0x00000000ff000000ULL) >> 24); \
+ (di).i[5] = (((from) & 0x0000000000ff0000ULL) >> 16); \
+ (di).i[6] = (((from) & 0x000000000000ff00ULL) >> 8); \
+ (di).i[7] = ((from) & 0x00000000000000ffULL); \
+} while (0)
+