1 files changed, 99 insertions, 66 deletions

diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c
index f761d98a4e90..9e91a2545fc8 100644
--- a/drivers/block/drbd/drbd_req.c
+++ b/drivers/block/drbd/drbd_req.c
@@ -59,17 +59,19 @@ static void _drbd_end_io_acct(struct drbd_conf *mdev, struct drbd_request *req)
 static void _req_is_done(struct drbd_conf *mdev, struct drbd_request *req, const int rw)
 {
 	const unsigned long s = req->rq_state;
+
+	/* remove it from the transfer log.
+	 * well, only if it had been there in the first
+	 * place... if it had not (local only or conflicting
+	 * and never sent), it should still be "empty" as
+	 * initialized in drbd_req_new(), so we can list_del() it
+	 * here unconditionally */
+	list_del(&req->tl_requests);
+
 	/* if it was a write, we may have to set the corresponding
 	 * bit(s) out-of-sync first. If it had a local part, we need to
 	 * release the reference to the activity log. */
 	if (rw == WRITE) {
-		/* remove it from the transfer log.
-		 * well, only if it had been there in the first
-		 * place... if it had not (local only or conflicting
-		 * and never sent), it should still be "empty" as
-		 * initialized in drbd_req_new(), so we can list_del() it
-		 * here unconditionally */
-		list_del(&req->tl_requests);
 		/* Set out-of-sync unless both OK flags are set
 		 * (local only or remote failed).
 		 * Other places where we set out-of-sync:
@@ -92,7 +94,8 @@ static void _req_is_done(struct drbd_conf *mdev, struct drbd_request *req, const
 		 */
 		if (s & RQ_LOCAL_MASK) {
 			if (get_ldev_if_state(mdev, D_FAILED)) {
-				drbd_al_complete_io(mdev, req->sector);
+				if (s & RQ_IN_ACT_LOG)
+					drbd_al_complete_io(mdev, req->sector);
 				put_ldev(mdev);
 			} else if (__ratelimit(&drbd_ratelimit_state)) {
 				dev_warn(DEV, "Should have called drbd_al_complete_io(, %llu), "
@@ -280,6 +283,14 @@ void _req_may_be_done(struct drbd_request *req, struct bio_and_error *m)
 	 * protocol A or B, barrier ack still pending... */
 }
 
+static void _req_may_be_done_not_susp(struct drbd_request *req, struct bio_and_error *m)
+{
+	struct drbd_conf *mdev = req->mdev;
+
+	if (!is_susp(mdev->state))
+		_req_may_be_done(req, m);
+}
+
 /*
  * checks whether there was an overlapping request
  * or ee already registered.
@@ -380,10 +391,11 @@ out_conflict:
  *  and it enforces that we have to think in a very structured manner
  *  about the "events" that may happen to a request during its life time ...
  */
-void __req_mod(struct drbd_request *req, enum drbd_req_event what,
+int __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		struct bio_and_error *m)
 {
 	struct drbd_conf *mdev = req->mdev;
+	int rv = 0;
 	m->bio = NULL;
 
 	switch (what) {
@@ -420,7 +432,7 @@ void __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		req->rq_state |= (RQ_LOCAL_COMPLETED|RQ_LOCAL_OK);
 		req->rq_state &= ~RQ_LOCAL_PENDING;
 
-		_req_may_be_done(req, m);
+		_req_may_be_done_not_susp(req, m);
 		put_ldev(mdev);
 		break;
 
@@ -429,7 +441,7 @@ void __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		req->rq_state &= ~RQ_LOCAL_PENDING;
 
 		__drbd_chk_io_error(mdev, FALSE);
-		_req_may_be_done(req, m);
+		_req_may_be_done_not_susp(req, m);
 		put_ldev(mdev);
 		break;
 
@@ -437,7 +449,7 @@ void __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		/* it is legal to fail READA */
 		req->rq_state |= RQ_LOCAL_COMPLETED;
 		req->rq_state &= ~RQ_LOCAL_PENDING;
-		_req_may_be_done(req, m);
+		_req_may_be_done_not_susp(req, m);
 		put_ldev(mdev);
 		break;
 
@@ -455,7 +467,7 @@ void __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		/* no point in retrying if there is no good remote data,
 		 * or we have no connection. */
 		if (mdev->state.pdsk != D_UP_TO_DATE) {
-			_req_may_be_done(req, m);
+			_req_may_be_done_not_susp(req, m);
 			break;
 		}
 
@@ -517,11 +529,9 @@ void __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		D_ASSERT(test_bit(CREATE_BARRIER, &mdev->flags) == 0);
 
 		req->epoch = mdev->newest_tle->br_number;
-		list_add_tail(&req->tl_requests,
-				&mdev->newest_tle->requests);
 
 		/* increment size of current epoch */
-		mdev->newest_tle->n_req++;
+		mdev->newest_tle->n_writes++;
 
 		/* queue work item to send data */
 		D_ASSERT(req->rq_state & RQ_NET_PENDING);
@@ -530,7 +540,7 @@ void __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		drbd_queue_work(&mdev->data.work, &req->w);
 
 		/* close the epoch, in case it outgrew the limit */
-		if (mdev->newest_tle->n_req >= mdev->net_conf->max_epoch_size)
+		if (mdev->newest_tle->n_writes >= mdev->net_conf->max_epoch_size)
 			queue_barrier(mdev);
 
 		break;
@@ -543,7 +553,7 @@ void __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		req->rq_state &= ~RQ_NET_QUEUED;
 		/* if we did it right, tl_clear should be scheduled only after
 		 * this, so this should not be necessary! */
-		_req_may_be_done(req, m);
+		_req_may_be_done_not_susp(req, m);
 		break;
 
 	case handed_over_to_network:
@@ -568,7 +578,7 @@ void __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		 * "completed_ok" events came in, once we return from
 		 * _drbd_send_zc_bio (drbd_send_dblock), we have to check
 		 * whether it is done already, and end it.  */
-		_req_may_be_done(req, m);
+		_req_may_be_done_not_susp(req, m);
 		break;
 
 	case read_retry_remote_canceled:
@@ -584,7 +594,7 @@ void __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		/* if it is still queued, we may not complete it here.
 		 * it will be canceled soon. */
 		if (!(req->rq_state & RQ_NET_QUEUED))
-			_req_may_be_done(req, m);
+			_req_may_be_done(req, m); /* Allowed while state.susp */
 		break;
 
 	case write_acked_by_peer_and_sis:
@@ -619,7 +629,7 @@ void __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		D_ASSERT(req->rq_state & RQ_NET_PENDING);
 		dec_ap_pending(mdev);
 		req->rq_state &= ~RQ_NET_PENDING;
-		_req_may_be_done(req, m);
+		_req_may_be_done_not_susp(req, m);
 		break;
 
 	case neg_acked:
@@ -629,11 +639,50 @@ void __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		req->rq_state &= ~(RQ_NET_OK|RQ_NET_PENDING);
 
 		req->rq_state |= RQ_NET_DONE;
-		_req_may_be_done(req, m);
+		_req_may_be_done_not_susp(req, m);
 		/* else: done by handed_over_to_network */
 		break;
 
+	case fail_frozen_disk_io:
+		if (!(req->rq_state & RQ_LOCAL_COMPLETED))
+			break;
+
+		_req_may_be_done(req, m); /* Allowed while state.susp */
+		break;
+
+	case restart_frozen_disk_io:
+		if (!(req->rq_state & RQ_LOCAL_COMPLETED))
+			break;
+
+		req->rq_state &= ~RQ_LOCAL_COMPLETED;
+
+		rv = MR_READ;
+		if (bio_data_dir(req->master_bio) == WRITE)
+			rv = MR_WRITE;
+
+		get_ldev(mdev);
+		req->w.cb = w_restart_disk_io;
+		drbd_queue_work(&mdev->data.work, &req->w);
+		break;
+
+	case resend:
+		/* 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
+		   We ensure that the peer was not rebooted */
+		if (!(req->rq_state & RQ_NET_OK)) {
+			if (req->w.cb) {
+				drbd_queue_work(&mdev->data.work, &req->w);
+				rv = req->rq_state & RQ_WRITE ? MR_WRITE : MR_READ;
+			}
+			break;
+		}
+		/* else, fall through to barrier_acked */
+
 	case barrier_acked:
+		if (!(req->rq_state & RQ_WRITE))
+			break;
+
 		if (req->rq_state & RQ_NET_PENDING) {
 			/* barrier came in before all requests have been acked.
 			 * this is bad, because if the connection is lost now,
@@ -643,7 +692,7 @@ void __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		}
 		D_ASSERT(req->rq_state & RQ_NET_SENT);
 		req->rq_state |= RQ_NET_DONE;
-		_req_may_be_done(req, m);
+		_req_may_be_done(req, m); /* Allowed while state.susp */
 		break;
 
 	case data_received:
@@ -651,9 +700,11 @@ void __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		dec_ap_pending(mdev);
 		req->rq_state &= ~RQ_NET_PENDING;
 		req->rq_state |= (RQ_NET_OK|RQ_NET_DONE);
-		_req_may_be_done(req, m);
+		_req_may_be_done_not_susp(req, m);
 		break;
 	};
+
+	return rv;
 }
 
 /* we may do a local read if:
@@ -752,14 +803,16 @@ static int drbd_make_request_common(struct drbd_conf *mdev, struct bio *bio)
 	 * resync extent to finish, and, if necessary, pulls in the target
 	 * extent into the activity log, which involves further disk io because
 	 * of transactional on-disk meta data updates. */
-	if (rw == WRITE && local)
+	if (rw == WRITE && local && !test_bit(AL_SUSPENDED, &mdev->flags)) {
+		req->rq_state |= RQ_IN_ACT_LOG;
 		drbd_al_begin_io(mdev, sector);
+	}
 
 	remote = remote && (mdev->state.pdsk == D_UP_TO_DATE ||
 			    (mdev->state.pdsk == D_INCONSISTENT &&
 			     mdev->state.conn >= C_CONNECTED));
 
-	if (!(local || remote) && !mdev->state.susp) {
+	if (!(local || remote) && !is_susp(mdev->state)) {
 		dev_err(DEV, "IO ERROR: neither local nor remote disk\n");
 		goto fail_free_complete;
 	}
@@ -785,7 +838,7 @@ allocate_barrier:
 	/* GOOD, everything prepared, grab the spin_lock */
 	spin_lock_irq(&mdev->req_lock);
 
-	if (mdev->state.susp) {
+	if (is_susp(mdev->state)) {
 		/* If we got suspended, use the retry mechanism of
 		   generic_make_request() to restart processing of this
 		   bio. In the next call to drbd_make_request_26
@@ -867,30 +920,10 @@ allocate_barrier:
 	/* check this request on the collision detection hash tables.
 	 * if we have a conflict, just complete it here.
 	 * THINK do we want to check reads, too? (I don't think so...) */
-	if (rw == WRITE && _req_conflicts(req)) {
-		/* this is a conflicting request.
-		 * even though it may have been only _partially_
-		 * overlapping with one of the currently pending requests,
-		 * without even submitting or sending it, we will
-		 * pretend that it was successfully served right now.
-		 */
-		if (local) {
-			bio_put(req->private_bio);
-			req->private_bio = NULL;
-			drbd_al_complete_io(mdev, req->sector);
-			put_ldev(mdev);
-			local = 0;
-		}
-		if (remote)
-			dec_ap_pending(mdev);
-		_drbd_end_io_acct(mdev, req);
-		/* THINK: do we want to fail it (-EIO), or pretend success? */
-		bio_endio(req->master_bio, 0);
-		req->master_bio = NULL;
-		dec_ap_bio(mdev);
-		drbd_req_free(req);
-		remote = 0;
-	}
+	if (rw == WRITE && _req_conflicts(req))
+		goto fail_conflicting;
+
+	list_add_tail(&req->tl_requests, &mdev->newest_tle->requests);
 
 	/* NOTE remote first: to get the concurrent write detection right,
 	 * we must register the request before start of local IO.  */
@@ -923,6 +956,21 @@ allocate_barrier:
 
 	return 0;
 
+fail_conflicting:
+	/* this is a conflicting request.
+	 * even though it may have been only _partially_
+	 * overlapping with one of the currently pending requests,
+	 * without even submitting or sending it, we will
+	 * pretend that it was successfully served right now.
+	 */
+	_drbd_end_io_acct(mdev, req);
+	spin_unlock_irq(&mdev->req_lock);
+	if (remote)
+		dec_ap_pending(mdev);
+	/* THINK: do we want to fail it (-EIO), or pretend success?
+	 * this pretends success. */
+	err = 0;
+
 fail_free_complete:
 	if (rw == WRITE && local)
 		drbd_al_complete_io(mdev, sector);
@@ -961,21 +1009,6 @@ static int drbd_fail_request_early(struct drbd_conf *mdev, int is_write)
 		return 1;
 	}
 
-	/*
-	 * Paranoia: we might have been primary, but sync target, or
-	 * even diskless, then lost the connection.
-	 * This should have been handled (panic? suspend?) somewhere
-	 * else. But maybe it was not, so check again here.
-	 * Caution: as long as we do not have a read/write lock on mdev,
-	 * to serialize state changes, this is racy, since we may lose
-	 * the connection *after* we test for the cstate.
-	 */
-	if (mdev->state.disk < D_UP_TO_DATE && mdev->state.pdsk < D_UP_TO_DATE) {
-		if (__ratelimit(&drbd_ratelimit_state))
-			dev_err(DEV, "Sorry, I have no access to good data anymore.\n");
-		return 1;
-	}
-
 	return 0;
 }