#define MD_SB_ERRORS 1
#define MD_SB_BITMAP_PRESENT 8 /* bitmap may be present nearby */
+
+/*
+ * Notes:
+ * - if an array is being reshaped (restriped) in order to change the
+ * the number of active devices in the array, 'raid_disks' will be
+ * the larger of the old and new numbers. 'delta_disks' will
+ * be the "new - old". So if +ve, raid_disks is the new value, and
+ * "raid_disks-delta_disks" is the old. If -ve, raid_disks is the
+ * old value and "raid_disks+delta_disks" is the new (smaller) value.
+ */
+
+
typedef struct mdp_superblock_s {
/*
* Constant generic information
__u32 cp_events_hi; /* 10 high-order of checkpoint update count */
#endif
__u32 recovery_cp; /* 11 recovery checkpoint sector count */
- __u32 gstate_sreserved[MD_SB_GENERIC_STATE_WORDS - 12];
+ /* There are only valid for minor_version > 90 */
+ __u64 reshape_position; /* 12,13 next address in array-space for reshape */
+ __u32 new_level; /* 14 new level we are reshaping to */
+ __u32 delta_disks; /* 15 change in number of raid_disks */
+ __u32 new_layout; /* 16 new layout */
+ __u32 new_chunk; /* 17 new chunk size (bytes) */
+ __u32 gstate_sreserved[MD_SB_GENERIC_STATE_WORDS - 18];
/*
* Personality information
* NOTE: signed, so bitmap can be before superblock
* only meaningful of feature_map[0] is set.
*/
- __u8 pad1[128-100]; /* set to 0 when written */
+
+ /* These are only valid with feature bit '4' */
+ __u32 new_level; /* new level we are reshaping to */
+ __u64 reshape_position; /* next address in array-space for reshape */
+ __u32 delta_disks; /* change in number of raid_disks */
+ __u32 new_layout; /* new layout */
+ __u32 new_chunk; /* new chunk size (bytes) */
+ __u8 pad1[128-124]; /* set to 0 when written */
/* constant this-device information - 64 bytes */
__u64 data_offset; /* sector start of data, often 0 */
/* feature_map bits */
#define MD_FEATURE_BITMAP_OFFSET 1
+#define MD_FEATURE_RECOVERY_OFFSET 2 /* recovery_offset is present and
+ * must be honoured
+ */
+#define MD_FEATURE_RESHAPE_ACTIVE 4
-#define MD_FEATURE_ALL 1
+#define MD_FEATURE_ALL (1|2|4)
#endif