From f1b29bcae116409db5e543622aadab43041c9ae9 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Sat, 1 May 2010 18:09:05 -0700 Subject: md/raid4: permit raid0 takeover For consistency allow raid4 to takeover raid0 in addition to raid5 (with a raid4 layout). Signed-off-by: Dan Williams --- drivers/md/raid5.c | 32 +++++++++++++++++--------------- 1 file changed, 17 insertions(+), 15 deletions(-) (limited to 'drivers/md') diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 2882a26646f..81563b7c035 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5610,10 +5610,17 @@ static void raid5_quiesce(mddev_t *mddev, int state) } -static void *raid5_takeover_raid0(mddev_t *mddev) +static void *raid45_takeover_raid0(mddev_t *mddev, int level) { + struct raid0_private_data *raid0_priv = mddev->private; - mddev->new_level = 5; + /* for raid0 takeover only one zone is supported */ + if (raid0_priv->nr_strip_zones > 1) { + printk(KERN_ERR "md: cannot takeover raid0 with more than one zone.\n"); + return ERR_PTR(-EINVAL); + } + + mddev->new_level = level; mddev->new_layout = ALGORITHM_PARITY_N; mddev->new_chunk_sectors = mddev->chunk_sectors; mddev->raid_disks += 1; @@ -5749,22 +5756,13 @@ static int raid6_check_reshape(mddev_t *mddev) static void *raid5_takeover(mddev_t *mddev) { /* raid5 can take over: - * raid0 - if all devices are the same - make it a raid4 layout + * raid0 - if there is only one strip zone - make it a raid4 layout * raid1 - if there are two drives. We need to know the chunk size * raid4 - trivial - just use a raid4 layout. * raid6 - Providing it is a *_6 layout */ - if (mddev->level == 0) { - /* for raid0 takeover only one zone is supported */ - struct raid0_private_data *raid0_priv - = mddev->private; - if (raid0_priv->nr_strip_zones > 1) { - printk(KERN_ERR "md: cannot takeover raid 0 with more than one zone.\n"); - return ERR_PTR(-EINVAL); - } - return raid5_takeover_raid0(mddev); - } - + if (mddev->level == 0) + return raid45_takeover_raid0(mddev, 5); if (mddev->level == 1) return raid5_takeover_raid1(mddev); if (mddev->level == 4) { @@ -5780,8 +5778,12 @@ static void *raid5_takeover(mddev_t *mddev) static void *raid4_takeover(mddev_t *mddev) { - /* raid4 can take over raid5 if layout is right. + /* raid4 can take over: + * raid0 - if there is only one strip zone + * raid5 - if layout is right */ + if (mddev->level == 0) + return raid45_takeover_raid0(mddev, 4); if (mddev->level == 5 && mddev->layout == ALGORITHM_PARITY_N) { mddev->new_layout = 0; -- cgit v1.2.3