Re: [md PATCH 3/5] md: Use added disks for external metadata case in start_reshape()
From: Neil Brown <hidden>
Date: 2010-06-16 04:58:18
On Wed, 9 Jun 2010 15:21:44 +0100 "Kwolek, Adam" [off-list ref] wrote:
(md: Online Capacity Expansion for IMSM) Disks added by mdadm for external metadata are not taken for configuration check before reshape. This causes configuration check fail. For reshape, we should check if added disks to volume by mdadm, will satisfy degradation condition after operation (comparing difference of target disk number and available disks number to mddev->max_degraded field). ---
I'm sorry but I don't understand what you are saying, and I think the required check is already in place. Could you please describe a specific circumstance where the current code fails? Thanks, NeilBrown
quoted hunk ↗ jump to hunk
drivers/md/raid5.c | 11 ++++++++++- 1 files changed, 10 insertions(+), 1 deletions(-)diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 546e23e..dc25a32 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c@@ -5411,6 +5411,7 @@ static int raid5_start_reshape(mddev_t *mddev) int spares = 0; int added_devices = 0; unsigned long flags; + int disk_count = 0; if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) return -EBUSY;@@ -5422,12 +5423,20 @@ static int raid5_start_reshape(mddev_t *mddev) if (rdev->raid_disk < 0 && !test_bit(Faulty, &rdev->flags)) spares++; + else + /* check reshape condition/spares are added already + */ + disk_count++; if (spares - mddev->degraded < mddev->delta_disks - conf->max_degraded) /* Not enough devices even to make a degraded array * of that size + * but check first if this is not reshape case + * if not reshape on degraded array /takeover/ than exit */ - return -EINVAL; + if ((conf->raid_disks + mddev->delta_disks) + > (disk_count + conf->max_degraded)) + return -EINVAL; /* Refuse to reduce size of the array. Any reductions in * array size must be through explicit setting of array_size