Target/iscsi,iser: Avoid accepting transport connections during stop stage

When the target is in stop stage, iSER transport initiates RDMA disconnects.
The iSER initiator may wish to establish a new connection over the
still existing network portal. In this case iSER transport should not
accept and resume new RDMA connections. In order to learn that, iscsi_np
is added with enabled flag so the iSER transport can check when deciding
weather to accept and resume a new connection request.

The iscsi_np is enabled after successful transport setup, and disabled
before iscsi_np login threads are cleaned up.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 10 insertions, 1 deletions

diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c
index 826eaf5741f6..a1710465faaf 100644
--- a/drivers/infiniband/ulp/isert/ib_isert.c
+++ b/drivers/infiniband/ulp/isert/ib_isert.c
@@ -562,7 +562,15 @@ isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
         struct isert_device *device;
         struct ib_device *ib_dev = cma_id->device;
         int ret = 0;
-        u8 pi_support = np->tpg_np->tpg->tpg_attrib.t10_pi;
+        u8 pi_support;
+
+        spin_lock_bh(&np->np_thread_lock);
+        if (!np->enabled) {
+                spin_unlock_bh(&np->np_thread_lock);
+                pr_debug("iscsi_np is not enabled, reject connect request\n");
+                return rdma_reject(cma_id, NULL, 0);
+        }
+        spin_unlock_bh(&np->np_thread_lock);
 
         pr_debug("Entering isert_connect_request cma_id: %p, context: %p\n",
                  cma_id, cma_id->context);
@@ -653,6 +661,7 @@ isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
                 goto out_mr;
         }
 
+        pi_support = np->tpg_np->tpg->tpg_attrib.t10_pi;
         if (pi_support && !device->pi_capable) {
                 pr_err("Protection information requested but not supported\n");
                 ret = -EINVAL;