raid5-cache: IO error handling
There are 3 places the raid5-cache dispatches IO. The discard IO error
doesn't matter, so we ignore it. The superblock write IO error can be
handled in MD core. The remaining are log write and flush. When the IO
error happens, we mark log disk faulty and fail all write IO. Read IO is
still allowed to run. Userspace will get a notification too and
corresponding daemon can choose setting raid array readonly for example.
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 693c000..68c36ce 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -3147,6 +3147,7 @@
* the data has not reached the cache yet.
*/
if (!test_bit(R5_Wantfill, &sh->dev[i].flags) &&
+ s->failed > conf->max_degraded &&
(!test_bit(R5_Insync, &sh->dev[i].flags) ||
test_bit(R5_ReadError, &sh->dev[i].flags))) {
spin_lock_irq(&sh->stripe_lock);
@@ -4015,6 +4016,7 @@
s->expanded = test_bit(STRIPE_EXPAND_READY, &sh->state) && !sh->batch_head;
s->failed_num[0] = -1;
s->failed_num[1] = -1;
+ s->log_failed = r5l_log_disk_error(conf);
/* Now to look around and see what can be done */
rcu_read_lock();
@@ -4358,7 +4360,7 @@
/* check if the array has lost more than max_degraded devices and,
* if so, some requests might need to be failed.
*/
- if (s.failed > conf->max_degraded) {
+ if (s.failed > conf->max_degraded || s.log_failed) {
sh->check_state = 0;
sh->reconstruct_state = 0;
break_stripe_batch_list(sh, 0);