#define MD_DISK_SYNC 2 /* disk is in sync with the raid set */
#define MD_DISK_REMOVED 3 /* disk is in sync with the raid set */
+#define MD_DISK_WRITEMOSTLY 9 /* disk is "write-mostly" is RAID1 config.
+ * read requests will only be sent here in
+ * dire need
+ */
+
typedef struct mdp_device_descriptor_s {
__u32 number; /* 0 Device number in the entire set */
__u32 major; /* 1 Device major number */
#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
*/
struct mdp_superblock_1 {
/* constant array information - 128 bytes */
- __u32 magic; /* MD_SB_MAGIC: 0xa92b4efc - little endian */
- __u32 major_version; /* 1 */
- __u32 feature_map; /* bit 0 set if 'bitmap_offset' is meaningful */
- __u32 pad0; /* always set to 0 when writing */
+ __le32 magic; /* MD_SB_MAGIC: 0xa92b4efc - little endian */
+ __le32 major_version; /* 1 */
+ __le32 feature_map; /* bit 0 set if 'bitmap_offset' is meaningful */
+ __le32 pad0; /* always set to 0 when writing */
__u8 set_uuid[16]; /* user-space generated. */
char set_name[32]; /* set and interpreted by user-space */
- __u64 ctime; /* lo 40 bits are seconds, top 24 are microseconds or 0*/
- __u32 level; /* -4 (multipath), -1 (linear), 0,1,4,5 */
- __u32 layout; /* only for raid5 currently */
- __u64 size; /* used size of component devices, in 512byte sectors */
+ __le64 ctime; /* lo 40 bits are seconds, top 24 are microseconds or 0*/
+ __le32 level; /* -4 (multipath), -1 (linear), 0,1,4,5 */
+ __le32 layout; /* only for raid5 and raid10 currently */
+ __le64 size; /* used size of component devices, in 512byte sectors */
- __u32 chunksize; /* in 512byte sectors */
- __u32 raid_disks;
- __u32 bitmap_offset; /* sectors after start of superblock that bitmap starts
+ __le32 chunksize; /* in 512byte sectors */
+ __le32 raid_disks;
+ __le32 bitmap_offset; /* sectors after start of superblock that bitmap starts
* 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' */
+ __le32 new_level; /* new level we are reshaping to */
+ __le64 reshape_position; /* next address in array-space for reshape */
+ __le32 delta_disks; /* change in number of raid_disks */
+ __le32 new_layout; /* new layout */
+ __le32 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 */
- __u64 data_size; /* sectors in this device that can be used for data */
- __u64 super_offset; /* sector start of this superblock */
- __u64 recovery_offset;/* sectors before this offset (from data_offset) have been recovered */
- __u32 dev_number; /* permanent identifier of this device - not role in raid */
- __u32 cnt_corrected_read; /* number of read errors that were corrected by re-writing */
+ __le64 data_offset; /* sector start of data, often 0 */
+ __le64 data_size; /* sectors in this device that can be used for data */
+ __le64 super_offset; /* sector start of this superblock */
+ __le64 recovery_offset;/* sectors before this offset (from data_offset) have been recovered */
+ __le32 dev_number; /* permanent identifier of this device - not role in raid */
+ __le32 cnt_corrected_read; /* number of read errors that were corrected by re-writing */
__u8 device_uuid[16]; /* user-space setable, ignored by kernel */
- __u8 pad2[64-56]; /* set to 0 when writing */
+ __u8 devflags; /* per-device flags. Only one defined...*/
+#define WriteMostly1 1 /* mask for writemostly flag in above */
+ __u8 pad2[64-57]; /* set to 0 when writing */
/* array state information - 64 bytes */
- __u64 utime; /* 40 bits second, 24 btes microseconds */
- __u64 events; /* incremented when superblock updated */
- __u64 resync_offset; /* data before this offset (from data_offset) known to be in sync */
- __u32 sb_csum; /* checksum upto devs[max_dev] */
- __u32 max_dev; /* size of devs[] array to consider */
+ __le64 utime; /* 40 bits second, 24 btes microseconds */
+ __le64 events; /* incremented when superblock updated */
+ __le64 resync_offset; /* data before this offset (from data_offset) known to be in sync */
+ __le32 sb_csum; /* checksum upto devs[max_dev] */
+ __le32 max_dev; /* size of devs[] array to consider */
__u8 pad3[64-32]; /* set to 0 when writing */
/* device state information. Indexed by dev_number.
* into the 'roles' value. If a device is spare or faulty, then it doesn't
* have a meaningful role.
*/
- __u16 dev_roles[0]; /* role in array, or 0xffff for a spare, or 0xfffe for faulty */
+ __le16 dev_roles[0]; /* role in array, or 0xffff for a spare, or 0xfffe for faulty */
};
+/* 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|2|4)
+
#endif