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>
This commit is contained in:
Philipp Reisner 2012-08-07 13:28:00 +02:00
parent e959d08d3e
commit 8a0bab2a6d
2 changed files with 13 additions and 5 deletions

View File

@ -683,6 +683,12 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what,
break;
case RESEND:
/* Simply complete (local only) READs. */
if (!(req->rq_state & RQ_WRITE) && !req->w.cb) {
mod_rq_state(req, m, RQ_COMPLETION_SUSP, 0);
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
(or the local completion?) was missing when we suspended.

View File

@ -1503,7 +1503,6 @@ static int w_after_conn_state_ch(struct drbd_work *w, int unused)
if (ns_max.susp_fen) {
/* case1: The outdate peer handler is successful: */
if (ns_max.pdsk <= D_OUTDATED) {
tl_clear(tconn);
rcu_read_lock();
idr_for_each_entry(&tconn->volumes, mdev, vnr) {
if (test_bit(NEW_CUR_UUID, &mdev->flags)) {
@ -1512,10 +1511,13 @@ static int w_after_conn_state_ch(struct drbd_work *w, int unused)
}
}
rcu_read_unlock();
conn_request_state(tconn,
(union drbd_state) { { .susp_fen = 1 } },
(union drbd_state) { { .susp_fen = 0 } },
CS_VERBOSE);
spin_lock_irq(&tconn->req_lock);
_tl_restart(tconn, CONNECTION_LOST_WHILE_PENDING);
_conn_request_state(tconn,
(union drbd_state) { { .susp_fen = 1 } },
(union drbd_state) { { .susp_fen = 0 } },
CS_VERBOSE);
spin_unlock_irq(&tconn->req_lock);
}
/* case2: The connection was established again: */
if (ns_min.conn >= C_CONNECTED) {