diff options
| author | Paul Clements | 2006-10-03 01:15:49 -0700 |
|---|---|---|
| committer | Linus Torvalds | 2006-10-03 08:04:17 -0700 |
| commit | 9b1d1dac181d8c1b9492e05cee660a985d035a06 (patch) | |
| tree | af12b1eaac4e0f7f3528ec26a223faeabed35845 /include/linux/raid | |
| parent | 76186dd8b73d2b7b9b4c8629b89c845e97009801 (diff) | |
[PATCH] md: new sysfs interface for setting bits in the write-intent-bitmap
Add a new sysfs interface that allows the bitmap of an array to be dirtied.
The interface is write-only, and is used as follows:
echo "1000" > /sys/block/md2/md/bitmap
(dirty the bit for chunk 1000 [offset 0] in the in-memory and on-disk
bitmaps of array md2)
echo "1000-2000" > /sys/block/md1/md/bitmap
(dirty the bits for chunks 1000-2000 in md1's bitmap)
This is useful, for example, in cluster environments where you may need to
combine two disjoint bitmaps into one (following a server failure, after a
secondary server has taken over the array). By combining the bitmaps on
the two servers, a full resync can be avoided (This was discussed on the
list back on March 18, 2005, "[PATCH 1/2] md bitmap bug fixes" thread).
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include/linux/raid')
| -rw-r--r-- | include/linux/raid/bitmap.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/linux/raid/bitmap.h b/include/linux/raid/bitmap.h index 63df898fe2e9..84d887751855 100644 --- a/include/linux/raid/bitmap.h +++ b/include/linux/raid/bitmap.h @@ -265,6 +265,8 @@ int bitmap_update_sb(struct bitmap *bitmap); int bitmap_setallbits(struct bitmap *bitmap); void bitmap_write_all(struct bitmap *bitmap); +void bitmap_dirty_bits(struct bitmap *bitmap, unsigned long s, unsigned long e); + /* these are exported */ int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors, int behind); |