drbd: Finish requests that completed while IO was frozen
Requests of an acked epoch are stored on the barrier_acked_requests list. In
case the private bio of such a request completes while IO on the drbd device
is suspended [req_mod(completed_ok)] then the request stays there.
When thawing IO because the fence_peer handler returned, then we use
tl_clear() to apply the connection_lost_while_pending event to all requests
on the transfer-log and the barrier_acked_requests list.
Up to now the connection_lost_while_pending event was not applied
on requests on the barrier_acked_requests list. Fixed that.
I.e. now the connection_lost_while_pending and resend events are
applied to requests on the barrier_acked_requests list. For that
it is necessary that the resend event finishes (local only)
READS correctly.
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 2e0e7fc..136db95 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -79,6 +79,7 @@
static void md_sync_timer_fn(unsigned long data);
static int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused);
static int w_go_diskless(struct drbd_conf *mdev, struct drbd_work *w, int unused);
+static void _tl_clear(struct drbd_conf *mdev);
MODULE_AUTHOR("Philipp Reisner <phil@linbit.com>, "
"Lars Ellenberg <lars@linbit.com>");
@@ -432,19 +433,10 @@
/* Actions operating on the disk state, also want to work on
requests that got barrier acked. */
- switch (what) {
- case fail_frozen_disk_io:
- case restart_frozen_disk_io:
- list_for_each_safe(le, tle, &mdev->barrier_acked_requests) {
- req = list_entry(le, struct drbd_request, tl_requests);
- _req_mod(req, what);
- }
- case connection_lost_while_pending:
- case resend:
- break;
- default:
- dev_err(DEV, "what = %d in _tl_restart()\n", what);
+ list_for_each_safe(le, tle, &mdev->barrier_acked_requests) {
+ req = list_entry(le, struct drbd_request, tl_requests);
+ _req_mod(req, what);
}
}
@@ -459,11 +451,16 @@
*/
void tl_clear(struct drbd_conf *mdev)
{
+ spin_lock_irq(&mdev->req_lock);
+ _tl_clear(mdev);
+ spin_unlock_irq(&mdev->req_lock);
+}
+
+static void _tl_clear(struct drbd_conf *mdev)
+{
struct list_head *le, *tle;
struct drbd_request *r;
- spin_lock_irq(&mdev->req_lock);
-
_tl_restart(mdev, connection_lost_while_pending);
/* we expect this list to be empty. */
@@ -482,7 +479,6 @@
memset(mdev->app_reads_hash, 0, APP_R_HSIZE*sizeof(void *));
- spin_unlock_irq(&mdev->req_lock);
}
void tl_restart(struct drbd_conf *mdev, enum drbd_req_event what)
@@ -1476,12 +1472,12 @@
if (ns.susp_fen) {
/* case1: The outdate peer handler is successful: */
if (os.pdsk > D_OUTDATED && ns.pdsk <= D_OUTDATED) {
- tl_clear(mdev);
if (test_bit(NEW_CUR_UUID, &mdev->flags)) {
drbd_uuid_new_current(mdev);
clear_bit(NEW_CUR_UUID, &mdev->flags);
}
spin_lock_irq(&mdev->req_lock);
+ _tl_clear(mdev);
_drbd_set_state(_NS(mdev, susp_fen, 0), CS_VERBOSE, NULL);
spin_unlock_irq(&mdev->req_lock);
}
diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c
index 0bb1e41..01b2ac6 100644
--- a/drivers/block/drbd/drbd_req.c
+++ b/drivers/block/drbd/drbd_req.c
@@ -695,6 +695,12 @@
break;
case resend:
+ /* Simply complete (local only) READs. */
+ if (!(req->rq_state & RQ_WRITE) && !req->w.cb) {
+ _req_may_be_done(req, m);
+ break;
+ }
+
/* If RQ_NET_OK is already set, we got a P_WRITE_ACK or P_RECV_ACK
before the connection loss (B&C only); only P_BARRIER_ACK was missing.
Trowing them out of the TL here by pretending we got a BARRIER_ACK