drbd: call local-io-error handler early

In case we want to hard-reset from the local-io-error handler,
we need to call it before notifying the peer or aborting local IO.
Otherwise the peer will advance its data generation UUIDs even
if secondary.

This way, local io error looks like a "regular" node crash,
which reduces the number of different failure cases.
This may be useful in a bigger picture where crashed or otherwise
"misbehaving" nodes are automatically re-deployed.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 91a4853..29a2764 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -1637,6 +1637,9 @@
 			eh = mdev->ldev->dc.on_io_error;
 			was_io_error = test_and_clear_bit(WAS_IO_ERROR, &mdev->flags);
 
+			if (was_io_error && eh == EP_CALL_HELPER)
+				drbd_khelper(mdev, "local-io-error");
+
 			/* Immediately allow completion of all application IO,
 			 * that waits for completion from the local disk,
 			 * if this was a force-detach due to disk_timeout
@@ -1672,9 +1675,6 @@
 			drbd_md_sync(mdev);
 		}
 		put_ldev(mdev);
-
-		if (was_io_error && eh == EP_CALL_HELPER)
-			drbd_khelper(mdev, "local-io-error");
 	}
 
         /* second half of local IO error, failure to attach,