diff options
| author | NeilBrown <neilb@cse.unsw.edu.au> | 2005-06-21 17:17:27 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-06-21 19:07:47 -0700 |
| commit | a654b9d8f851f4ca02649d5825cbe6c608adb10c (patch) | |
| tree | 747301647f619a9f1dd48f4d6be96b5e35d2484c /include/linux/raid/md_p.h | |
| parent | 3d310eb7b3df1252e8595d059d982b0a9825a137 (diff) | |
[PATCH] md: allow md intent bitmap to be stored near the superblock.
This provides an alternate to storing the bitmap in a separate file. The
bitmap can be stored at a given offset from the superblock. Obviously the
creator of the array must make sure this doesn't intersect with data....
After is good for version-0.90 superblocks.
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include/linux/raid/md_p.h')
| -rw-r--r-- | include/linux/raid/md_p.h | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/include/linux/raid/md_p.h b/include/linux/raid/md_p.h index 8ba95d67329..8e592a25a8b 100644 --- a/include/linux/raid/md_p.h +++ b/include/linux/raid/md_p.h @@ -96,6 +96,7 @@ typedef struct mdp_device_descriptor_s { #define MD_SB_CLEAN 0 #define MD_SB_ERRORS 1 +#define MD_SB_BITMAP_PRESENT 8 /* bitmap may be present nearby */ typedef struct mdp_superblock_s { /* * Constant generic information @@ -184,7 +185,7 @@ struct mdp_superblock_1 { /* constant array information - 128 bytes */ __u32 magic; /* MD_SB_MAGIC: 0xa92b4efc - little endian */ __u32 major_version; /* 1 */ - __u32 feature_map; /* 0 for now */ + __u32 feature_map; /* bit 0 set if 'bitmap_offset' is meaningful */ __u32 pad0; /* always set to 0 when writing */ __u8 set_uuid[16]; /* user-space generated. */ @@ -197,6 +198,10 @@ struct mdp_superblock_1 { __u32 chunksize; /* in 512byte sectors */ __u32 raid_disks; + __u32 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[128-96]; /* set to 0 when written */ /* constant this-device information - 64 bytes */ |