md: add takeover support for converting raid6 back into raid5

If a raid6 is still in the layout that comes from converting raid5
into a raid6. this will allow us to convert it back again.

Signed-off-by: NeilBrown <neilb@suse.de>
This commit is contained in:
NeilBrown 2009-03-31 14:57:20 +11:00
parent e9d4758f6e
commit fc9739c6d6

View File

@ -4912,6 +4912,39 @@ static void *raid5_takeover_raid1(mddev_t *mddev)
return setup_conf(mddev);
}
static void *raid5_takeover_raid6(mddev_t *mddev)
{
int new_layout;
switch (mddev->layout) {
case ALGORITHM_LEFT_ASYMMETRIC_6:
new_layout = ALGORITHM_LEFT_ASYMMETRIC;
break;
case ALGORITHM_RIGHT_ASYMMETRIC_6:
new_layout = ALGORITHM_RIGHT_ASYMMETRIC;
break;
case ALGORITHM_LEFT_SYMMETRIC_6:
new_layout = ALGORITHM_LEFT_SYMMETRIC;
break;
case ALGORITHM_RIGHT_SYMMETRIC_6:
new_layout = ALGORITHM_RIGHT_SYMMETRIC;
break;
case ALGORITHM_PARITY_0_6:
new_layout = ALGORITHM_PARITY_0;
break;
case ALGORITHM_PARITY_N:
new_layout = ALGORITHM_PARITY_N;
break;
default:
return ERR_PTR(-EINVAL);
}
mddev->new_level = 5;
mddev->new_layout = new_layout;
mddev->delta_disks = -1;
mddev->raid_disks -= 1;
return setup_conf(mddev);
}
static int raid5_reconfig(mddev_t *mddev, int new_layout, int new_chunk)
{
@ -4972,6 +5005,8 @@ static void *raid5_takeover(mddev_t *mddev)
mddev->new_level = 5;
return setup_conf(mddev);
}
if (mddev->level == 6)
return raid5_takeover_raid6(mddev);
return ERR_PTR(-EINVAL);
}