md: Handle growth of v1.x metadata correctly.

The v1.x metadata does not have a fixed size and can grow
when devices are added.
If it grows enough to require an extra sector of storage,
we need to update the 'sb_size' to match.

Without this, md can write out an incomplete superblock with a
bad checksum, which will be rejected when trying to re-assemble
the array.

Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
This commit is contained in:
NeilBrown 2009-08-03 10:59:57 +10:00
parent 3673f305fa
commit 70471dafe3

View File

@ -1399,8 +1399,14 @@ static void super_1_sync(mddev_t *mddev, mdk_rdev_t *rdev)
if (rdev2->desc_nr+1 > max_dev)
max_dev = rdev2->desc_nr+1;
if (max_dev > le32_to_cpu(sb->max_dev))
if (max_dev > le32_to_cpu(sb->max_dev)) {
int bmask;
sb->max_dev = cpu_to_le32(max_dev);
rdev->sb_size = max_dev * 2 + 256;
bmask = queue_logical_block_size(rdev->bdev->bd_disk->queue)-1;
if (rdev->sb_size & bmask)
rdev->sb_size = (rdev->sb_size | bmask) + 1;
}
for (i=0; i<max_dev;i++)
sb->dev_roles[i] = cpu_to_le16(0xfffe);