drbd: Do not allow a fencing-policy of resource-and-stonith with protocol A

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

2 files changed, 20 insertions, 2 deletions

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 563a6ade0179..5288bd72cd27 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -806,6 +806,15 @@ static int drbd_nl_disk_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp
                 goto fail;
         }
 
+        if (get_net_conf(mdev)) {
+                int prot = mdev->net_conf->wire_protocol;
+                put_net_conf(mdev);
+                if (nbc->dc.fencing == FP_STONITH && prot == DRBD_PROT_A) {
+                        retcode = ERR_STONITH_AND_PROT_A;
+                        goto fail;
+                }
+        }
+
         nbc->lo_file = filp_open(nbc->dc.backing_dev, O_RDWR, 0);
         if (IS_ERR(nbc->lo_file)) {
                 dev_err(DEV, "open(\"%s\") failed with %ld\n", nbc->dc.backing_dev,
@@ -1238,7 +1247,16 @@ static int drbd_nl_net_conf(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp,
             && (new_conf->wire_protocol != DRBD_PROT_C)) {
                 retcode = ERR_NOT_PROTO_C;
                 goto fail;
-        };
+        }
+
+        if (get_ldev(mdev)) {
+                enum drbd_fencing_p fp = mdev->ldev->dc.fencing;
+                put_ldev(mdev);
+                if (new_conf->wire_protocol == DRBD_PROT_A && fp == FP_STONITH) {
+                        retcode = ERR_STONITH_AND_PROT_A;
+                        goto fail;
+                }
+        }
 
         if (mdev->state.role == R_PRIMARY && new_conf->want_lose) {
                 retcode = ERR_DISCARD;
diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c
index 8259d4f77285..fbe027886bad 100644
--- a/drivers/block/drbd/drbd_req.c
+++ b/drivers/block/drbd/drbd_req.c
@@ -660,7 +660,7 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what,
 
         case resend:
                 /* If RQ_NET_OK is already set, we got a P_WRITE_ACK or P_RECV_ACK
-                   before the connection loss; only P_BARRIER_ACK was missing.
+                   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
                    TODO: Either resync them, or ensure peer was not rebooted. */
                 if (!(req->rq_state & RQ_NET_OK)) {