[SCSI] libiscsi, iser, tcp: remove recv_lock

The recv lock was defined so the iscsi layer could block
the recv path from processing IO during recovery. It
turns out iser just set a lock to that pointer which was pointless.

We now disconnect the transport connection before doing recovery
so we do not need the recv lock. For iscsi_tcp we still stop
the recv path incase older tools are being used.

This patch also has iscsi_itt_to_ctask user grab the session lock
and has the caller access the task with the lock or get a ref
to it in case the target is broken and sends a tmf success response
then sends data or a response for the command that was supposed to
be affected bty the tmf.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

3 files changed, 16 insertions, 12 deletions

diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.c b/drivers/infiniband/ulp/iser/iscsi_iser.c
index 08edbaf8922..c02eabd383a 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.c
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.c
@@ -281,9 +281,6 @@ iscsi_iser_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
         conn->max_recv_dlength = 128;
 
         iser_conn = conn->dd_data;
-        /* currently this is the only field which need to be initiated */
-        rwlock_init(&iser_conn->lock);
-
         conn->dd_data = iser_conn;
         iser_conn->iscsi_conn = conn;
 
@@ -342,9 +339,6 @@ iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session,
         ib_conn->iser_conn = iser_conn;
         iser_conn->ib_conn  = ib_conn;
         iser_conn_get(ib_conn);
-
-        conn->recv_lock = &iser_conn->lock;
-
         return 0;
 }
 
@@ -355,12 +349,18 @@ iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
         struct iscsi_iser_conn *iser_conn = conn->dd_data;
         struct iser_conn *ib_conn = iser_conn->ib_conn;
 
-        iscsi_conn_stop(cls_conn, flag);
         /*
-         * There is no unbind event so the stop callback
-         * must release the ref from the bind.
+         * Userspace may have goofed up and not bound the connection or
+         * might have only partially setup the connection.
          */
-        iser_conn_put(ib_conn);
+        if (ib_conn) {
+                iscsi_conn_stop(cls_conn, flag);
+                /*
+                 * There is no unbind event so the stop callback
+                 * must release the ref from the bind.
+                 */
+                iser_conn_put(ib_conn);
+        }
         iser_conn->ib_conn = NULL;
 }
 
diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.h b/drivers/infiniband/ulp/iser/iscsi_iser.h
index cdf48763b08..a547edeea96 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.h
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.h
@@ -263,8 +263,6 @@ struct iser_conn {
 struct iscsi_iser_conn {
         struct iscsi_conn            *iscsi_conn;/* ptr to iscsi conn */
         struct iser_conn             *ib_conn;   /* iSER IB conn      */
-
-        rwlock_t                     lock;
 };
 
 struct iscsi_iser_task {
diff --git a/drivers/infiniband/ulp/iser/iser_initiator.c b/drivers/infiniband/ulp/iser/iser_initiator.c
index 35af60a23c6..c3608392213 100644
--- a/drivers/infiniband/ulp/iser/iser_initiator.c
+++ b/drivers/infiniband/ulp/iser/iser_initiator.c
@@ -558,7 +558,12 @@ void iser_rcv_completion(struct iser_desc *rx_desc,
         opcode = hdr->opcode & ISCSI_OPCODE_MASK;
 
         if (opcode == ISCSI_OP_SCSI_CMD_RSP) {
+                spin_lock(&conn->iscsi_conn->session->lock);
                 task = iscsi_itt_to_ctask(conn->iscsi_conn, hdr->itt);
+                if (task)
+                        __iscsi_get_task(task);
+                spin_unlock(&conn->iscsi_conn->session->lock);
+
                 if (!task)
                         iser_err("itt can't be matched to task!!! "
                                  "conn %p opcode %d itt %d\n",
@@ -568,6 +573,7 @@ void iser_rcv_completion(struct iser_desc *rx_desc,
                         iser_dbg("itt %d task %p\n",hdr->itt, task);
                         iser_task->status = ISER_TASK_STATUS_COMPLETED;
                         iser_task_rdma_finalize(iser_task);
+                        iscsi_put_task(task);
                 }
         }
         iser_dto_buffs_release(dto);