IB/cm: Update protocol to support XRC

Update the REQ and REP messages to support XRC connection setup
according to the XRC Annex.  Several existing fields must be set to 0 or
1 when connecting XRC QPs, and a reserved field is changed to an
extended transport type.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

2 files changed, 43 insertions, 16 deletions

diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c
index fc0f2bd9ca8..d2e1cfb206b 100644
--- a/drivers/infiniband/core/cm.c
+++ b/drivers/infiniband/core/cm.c
@@ -1008,7 +1008,6 @@ static void cm_format_req(struct cm_req_msg *req_msg,
         req_msg->service_id = param->service_id;
         req_msg->local_ca_guid = cm_id_priv->id.device->node_guid;
         cm_req_set_local_qpn(req_msg, cpu_to_be32(param->qp_num));
-        cm_req_set_resp_res(req_msg, param->responder_resources);
         cm_req_set_init_depth(req_msg, param->initiator_depth);
         cm_req_set_remote_resp_timeout(req_msg,
                                        param->remote_cm_response_timeout);
@@ -1017,12 +1016,16 @@ static void cm_format_req(struct cm_req_msg *req_msg,
         cm_req_set_starting_psn(req_msg, cpu_to_be32(param->starting_psn));
         cm_req_set_local_resp_timeout(req_msg,
                                       param->local_cm_response_timeout);
-        cm_req_set_retry_count(req_msg, param->retry_count);
         req_msg->pkey = param->primary_path->pkey;
         cm_req_set_path_mtu(req_msg, param->primary_path->mtu);
-        cm_req_set_rnr_retry_count(req_msg, param->rnr_retry_count);
         cm_req_set_max_cm_retries(req_msg, param->max_cm_retries);
-        cm_req_set_srq(req_msg, param->srq);
+
+        if (param->qp_type != IB_QPT_XRC_INI) {
+                cm_req_set_resp_res(req_msg, param->responder_resources);
+                cm_req_set_retry_count(req_msg, param->retry_count);
+                cm_req_set_rnr_retry_count(req_msg, param->rnr_retry_count);
+                cm_req_set_srq(req_msg, param->srq);
+        }
 
         if (pri_path->hop_limit <= 1) {
                 req_msg->primary_local_lid = pri_path->slid;
@@ -1080,7 +1083,8 @@ static int cm_validate_req_param(struct ib_cm_req_param *param)
         if (!param->primary_path)
                 return -EINVAL;
 
-        if (param->qp_type != IB_QPT_RC && param->qp_type != IB_QPT_UC)
+        if (param->qp_type != IB_QPT_RC && param->qp_type != IB_QPT_UC &&
+            param->qp_type != IB_QPT_XRC_INI)
                 return -EINVAL;
 
         if (param->private_data &&
@@ -1604,15 +1608,20 @@ static void cm_format_rep(struct cm_rep_msg *rep_msg,
         cm_rep_set_local_qpn(rep_msg, cpu_to_be32(param->qp_num));
         cm_rep_set_starting_psn(rep_msg, cpu_to_be32(param->starting_psn));
         rep_msg->resp_resources = param->responder_resources;
-        rep_msg->initiator_depth = param->initiator_depth;
         cm_rep_set_target_ack_delay(rep_msg,
                                     cm_id_priv->av.port->cm_dev->ack_delay);
         cm_rep_set_failover(rep_msg, param->failover_accepted);
-        cm_rep_set_flow_ctrl(rep_msg, param->flow_control);
         cm_rep_set_rnr_retry_count(rep_msg, param->rnr_retry_count);
-        cm_rep_set_srq(rep_msg, param->srq);
         rep_msg->local_ca_guid = cm_id_priv->id.device->node_guid;
 
+        if (cm_id_priv->qp_type != IB_QPT_XRC_TGT) {
+                rep_msg->initiator_depth = param->initiator_depth;
+                cm_rep_set_flow_ctrl(rep_msg, param->flow_control);
+                cm_rep_set_srq(rep_msg, param->srq);
+        } else {
+                cm_rep_set_srq(rep_msg, 1);
+        }
+
         if (param->private_data && param->private_data_len)
                 memcpy(rep_msg->private_data, param->private_data,
                        param->private_data_len);
@@ -3492,7 +3501,8 @@ static int cm_init_qp_rtr_attr(struct cm_id_private *cm_id_priv,
                 qp_attr->path_mtu = cm_id_priv->path_mtu;
                 qp_attr->dest_qp_num = be32_to_cpu(cm_id_priv->remote_qpn);
                 qp_attr->rq_psn = be32_to_cpu(cm_id_priv->rq_psn);
-                if (cm_id_priv->qp_type == IB_QPT_RC) {
+                if (cm_id_priv->qp_type == IB_QPT_RC ||
+                    cm_id_priv->qp_type == IB_QPT_XRC_TGT) {
                         *qp_attr_mask |= IB_QP_MAX_DEST_RD_ATOMIC |
                                          IB_QP_MIN_RNR_TIMER;
                         qp_attr->max_dest_rd_atomic =
@@ -3537,15 +3547,21 @@ static int cm_init_qp_rts_attr(struct cm_id_private *cm_id_priv,
                 if (cm_id_priv->id.lap_state == IB_CM_LAP_UNINIT) {
                         *qp_attr_mask = IB_QP_STATE | IB_QP_SQ_PSN;
                         qp_attr->sq_psn = be32_to_cpu(cm_id_priv->sq_psn);
-                        if (cm_id_priv->qp_type == IB_QPT_RC) {
-                                *qp_attr_mask |= IB_QP_TIMEOUT | IB_QP_RETRY_CNT |
-                                                 IB_QP_RNR_RETRY |
+                        switch (cm_id_priv->qp_type) {
+                        case IB_QPT_RC:
+                        case IB_QPT_XRC_INI:
+                                *qp_attr_mask |= IB_QP_RETRY_CNT | IB_QP_RNR_RETRY |
                                                  IB_QP_MAX_QP_RD_ATOMIC;
-                                qp_attr->timeout = cm_id_priv->av.timeout;
                                 qp_attr->retry_cnt = cm_id_priv->retry_count;
                                 qp_attr->rnr_retry = cm_id_priv->rnr_retry_count;
-                                qp_attr->max_rd_atomic =
-                                        cm_id_priv->initiator_depth;
+                                qp_attr->max_rd_atomic = cm_id_priv->initiator_depth;
+                                /* fall through */
+                        case IB_QPT_XRC_TGT:
+                                *qp_attr_mask |= IB_QP_TIMEOUT;
+                                qp_attr->timeout = cm_id_priv->av.timeout;
+                                break;
+                        default:
+                                break;
                         }
                         if (cm_id_priv->alt_av.ah_attr.dlid) {
                                 *qp_attr_mask |= IB_QP_PATH_MIG_STATE;
diff --git a/drivers/infiniband/core/cm_msgs.h b/drivers/infiniband/core/cm_msgs.h
index 7e63c08f697..3ade3202597 100644
--- a/drivers/infiniband/core/cm_msgs.h
+++ b/drivers/infiniband/core/cm_msgs.h
@@ -86,7 +86,7 @@ struct cm_req_msg {
         __be16 pkey;
         /* path MTU:4, RDC exists:1, RNR retry count:3. */
         u8 offset50;
-        /* max CM Retries:4, SRQ:1, rsvd:3 */
+        /* max CM Retries:4, SRQ:1, extended transport type:3 */
         u8 offset51;
 
         __be16 primary_local_lid;
@@ -175,6 +175,11 @@ static inline enum ib_qp_type cm_req_get_qp_type(struct cm_req_msg *req_msg)
         switch(transport_type) {
         case 0: return IB_QPT_RC;
         case 1: return IB_QPT_UC;
+        case 3:
+                switch (req_msg->offset51 & 0x7) {
+                case 1: return IB_QPT_XRC_TGT;
+                default: return 0;
+                }
         default: return 0;
         }
 }
@@ -188,6 +193,12 @@ static inline void cm_req_set_qp_type(struct cm_req_msg *req_msg,
                                                   req_msg->offset40) &
                                                    0xFFFFFFF9) | 0x2);
                 break;
+        case IB_QPT_XRC_INI:
+                req_msg->offset40 = cpu_to_be32((be32_to_cpu(
+                                                 req_msg->offset40) &
+                                                   0xFFFFFFF9) | 0x6);
+                req_msg->offset51 = (req_msg->offset51 & 0xF8) | 1;
+                break;
         default:
                 req_msg->offset40 = cpu_to_be32(be32_to_cpu(
                                                  req_msg->offset40) &