* [PATCH md ] md: allow degraded raid1 array to resync after an unclean shutdown.
[not found] <20050323142016.12770.patches@notabene>
@ 2005-03-23 3:31 ` NeilBrown
2005-03-27 2:38 ` Molle Bestefich
0 siblings, 1 reply; 2+ messages in thread
From: NeilBrown @ 2005-03-23 3:31 UTC (permalink / raw)
To: Marcelo Tosatti; +Cc: linux-raid
The following is (I think) appropriate for 2.4.30. The bug it fixes
can result in data corruption in a fairly unusual circumstance (having
a 3 drive raid1 array running in degraded mode, and suffering a system
crash).
### Comments for Changeset
If a raid1 array has more than two devices, and not all are working,
then it will not resync after an unclean shutdown (as it will think
that it should reconstruct a failed drive, and will find there aren't
any spares...)
This patch fixes the problem.
Problem found by Mario Holbe <Mario.Holbe@TU-Ilmenau.DE> (thanks!)
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
### Diffstat output
./drivers/md/raid1.c | 13 ++++++++-----
1 files changed, 8 insertions(+), 5 deletions(-)
diff ./drivers/md/raid1.c~current~ ./drivers/md/raid1.c
--- ./drivers/md/raid1.c~current~ 2005-03-23 11:28:56.000000000 +1100
+++ ./drivers/md/raid1.c 2005-03-23 11:38:41.000000000 +1100
@@ -891,6 +891,8 @@ static int raid1_diskop(mddev_t *mddev,
mdp_disk_t *failed_desc, *spare_desc, *added_desc;
mdk_rdev_t *spare_rdev, *failed_rdev;
+ if (conf->resync_mirrors)
+ return 1; /* Cannot do any diskops during a resync */
switch (state) {
case DISKOP_SPARE_ACTIVE:
@@ -1333,6 +1335,8 @@ static void raid1syncd (void *data)
up(&mddev->recovery_sem);
raid1_shrink_buffers(conf);
+
+ md_recover_arrays(); /* incase we are degraded and a spare is available */
}
/*
@@ -1741,10 +1745,6 @@ static int raid1_run (mddev_t *mddev)
conf->last_used = j;
- if (conf->working_disks != sb->raid_disks) {
- printk(KERN_ALERT "raid1: md%d, not all disks are operational -- trying to recover array\n", mdidx(mddev));
- start_recovery = 1;
- }
{
const char * name = "raid1d";
@@ -1756,7 +1756,7 @@ static int raid1_run (mddev_t *mddev)
}
}
- if (!start_recovery && !(sb->state & (1 << MD_SB_CLEAN)) &&
+ if (!(sb->state & (1 << MD_SB_CLEAN)) &&
(conf->working_disks > 1)) {
const char * name = "raid1syncd";
@@ -1769,6 +1769,9 @@ static int raid1_run (mddev_t *mddev)
printk(START_RESYNC, mdidx(mddev));
conf->resync_mirrors = 1;
md_wakeup_thread(conf->resync_thread);
+ } else if (conf->working_disks != sb->raid_disks) {
+ printk(KERN_ALERT "raid1: md%d, not all disks are operational -- trying to recover array\n", mdidx(mddev));
+ start_recovery = 1;
}
/*
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