md: make error_handler functions more uniform and correct.
- there is no need to test_bit Faulty, as that was already done in
md_error which is the only caller of these functions.
- MD_CHANGE_DEVS should be set *after* faulty is set to ensure
metadata is updated correctly.
- spinlock should be held while updating ->degraded.
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index 0254712..3535c23 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -186,6 +186,7 @@
static void multipath_error (mddev_t *mddev, mdk_rdev_t *rdev)
{
multipath_conf_t *conf = mddev->private;
+ char b[BDEVNAME_SIZE];
if (conf->raid_disks - mddev->degraded <= 1) {
/*
@@ -194,26 +195,27 @@
* which has just failed.
*/
printk(KERN_ALERT
- "multipath: only one IO path left and IO error.\n");
+ "multipath: only one IO path left and IO error.\n");
/* leave it active... it's all we have */
- } else {
- /*
- * Mark disk as unusable
- */
- if (!test_bit(Faulty, &rdev->flags)) {
- char b[BDEVNAME_SIZE];
- clear_bit(In_sync, &rdev->flags);
- set_bit(Faulty, &rdev->flags);
- set_bit(MD_CHANGE_DEVS, &mddev->flags);
- mddev->degraded++;
- printk(KERN_ALERT "multipath: IO failure on %s,"
- " disabling IO path.\n"
- "multipath: Operation continuing"
- " on %d IO paths.\n",
- bdevname (rdev->bdev,b),
- conf->raid_disks - mddev->degraded);
- }
+ return;
}
+ /*
+ * Mark disk as unusable
+ */
+ if (test_and_clear_bit(In_sync, &rdev->flags)) {
+ unsigned long flags;
+ spin_lock_irqsave(&conf->device_lock, flags);
+ mddev->degraded++;
+ spin_unlock_irqrestore(&conf->device_lock, flags);
+ }
+ set_bit(Faulty, &rdev->flags);
+ set_bit(MD_CHANGE_DEVS, &mddev->flags);
+ printk(KERN_ALERT "multipath: IO failure on %s,"
+ " disabling IO path.\n"
+ "multipath: Operation continuing"
+ " on %d IO paths.\n",
+ bdevname(rdev->bdev, b),
+ conf->raid_disks - mddev->degraded);
}
static void print_multipath_conf (multipath_conf_t *conf)
@@ -273,9 +275,11 @@
PAGE_CACHE_SIZE - 1);
}
+ spin_lock_irq(&conf->device_lock);
mddev->degraded--;
rdev->raid_disk = path;
set_bit(In_sync, &rdev->flags);
+ spin_unlock_irq(&conf->device_lock);
rcu_assign_pointer(p->rdev, rdev);
err = 0;
md_integrity_add_rdev(rdev, mddev);