RDMA/nes: Fixes for IRD/ORD negotiation with MPA v2

Fixes to enable the negotiation of the supported IRD/ORD sizes with
the peer when exchanging MPA v2 messages in connection establishment.

Signed-off-by: Tatyana Nikolova <tatyana.e.nikolova@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

2 files changed, 93 insertions, 29 deletions

diff --git a/drivers/infiniband/hw/nes/nes_cm.c b/drivers/infiniband/hw/nes/nes_cm.c
index 9c9f2f57e960..e852a3a42b9e 100644
--- a/drivers/infiniband/hw/nes/nes_cm.c
+++ b/drivers/infiniband/hw/nes/nes_cm.c
@@ -128,6 +128,7 @@ static void build_mpa_v1(struct nes_cm_node *, void *, u8);
 static void build_rdma0_msg(struct nes_cm_node *, struct nes_qp **);
 
 static void print_core(struct nes_cm_core *core);
+static void record_ird_ord(struct nes_cm_node *, u16, u16);
 
 /* External CM API Interface */
 /* instance of function pointers for client API */
@@ -317,7 +318,6 @@ static int parse_mpa(struct nes_cm_node *cm_node, u8 *buffer, u32 *type,
                 }
         }
 
-
         if (priv_data_len + mpa_hdr_len != len) {
                 nes_debug(NES_DBG_CM, "The received ietf buffer was not right"
                         " complete (%x + %x != %x)\n",
@@ -356,25 +356,57 @@ static int parse_mpa(struct nes_cm_node *cm_node, u8 *buffer, u32 *type,
                         /* send reset */
                         return -EINVAL;
                 }
+                if (ird_size == IETF_NO_IRD_ORD || ord_size == IETF_NO_IRD_ORD)
+                        cm_node->mpav2_ird_ord = IETF_NO_IRD_ORD;
 
-                if (cm_node->state != NES_CM_STATE_MPAREQ_SENT) {
+                if (cm_node->mpav2_ird_ord != IETF_NO_IRD_ORD) {
                         /* responder */
-                        if (cm_node->ord_size > ird_size)
-                                cm_node->ord_size = ird_size;
-                } else {
-                        /* initiator */
-                        if (cm_node->ord_size > ird_size)
-                                cm_node->ord_size = ird_size;
-
-                        if (cm_node->ird_size < ord_size) {
-                                /* no resources available */
-                                /* send terminate message */
-                                return -EINVAL;
+                        if (cm_node->state != NES_CM_STATE_MPAREQ_SENT) {
+                                /* we are still negotiating */
+                                if (ord_size > NES_MAX_IRD) {
+                                        cm_node->ird_size = NES_MAX_IRD;
+                                } else {
+                                        cm_node->ird_size = ord_size;
+                                        if (ord_size == 0 &&
+                                        (rtr_ctrl_ord & IETF_RDMA0_READ)) {
+                                                cm_node->ird_size = 1;
+                                                nes_debug(NES_DBG_CM,
+                                                "%s: Remote peer doesn't support RDMA0_READ (ord=%u)\n",
+                                                        __func__, ord_size);
+                                        }
+                                }
+                                if (ird_size > NES_MAX_ORD)
+                                        cm_node->ord_size = NES_MAX_ORD;
+                                else
+                                        cm_node->ord_size = ird_size;
+                        } else { /* initiator */
+                                if (ord_size > NES_MAX_IRD) {
+                                        nes_debug(NES_DBG_CM,
+                                        "%s: Unable to support the requested (ord =%u)\n",
+                                                        __func__, ord_size);
+                                        return -EINVAL;
+                                }
+                                cm_node->ird_size = ord_size;
+
+                                if (ird_size > NES_MAX_ORD) {
+                                        cm_node->ord_size = NES_MAX_ORD;
+                                } else {
+                                        if (ird_size == 0 &&
+                                        (rtr_ctrl_ord & IETF_RDMA0_READ)) {
+                                                nes_debug(NES_DBG_CM,
+                                                "%s: Remote peer doesn't support RDMA0_READ (ird=%u)\n",
+                                                        __func__, ird_size);
+                                                return -EINVAL;
+                                        } else {
+                                                cm_node->ord_size = ird_size;
+                                        }
+                                }
                         }
                 }
 
                 if (rtr_ctrl_ord & IETF_RDMA0_READ) {
                         cm_node->send_rdma0_op = SEND_RDMA_READ_ZERO;
+
                 } else if (rtr_ctrl_ord & IETF_RDMA0_WRITE) {
                         cm_node->send_rdma0_op = SEND_RDMA_WRITE_ZERO;
                 } else {        /* Not supported RDMA0 operation */
@@ -514,6 +546,19 @@ static void print_core(struct nes_cm_core *core)
         nes_debug(NES_DBG_CM, "-------------- end core ---------------\n");
 }
 
+static void record_ird_ord(struct nes_cm_node *cm_node,
+                                        u16 conn_ird, u16 conn_ord)
+{
+        if (conn_ird > NES_MAX_IRD)
+                conn_ird = NES_MAX_IRD;
+
+        if (conn_ord > NES_MAX_ORD)
+                conn_ord = NES_MAX_ORD;
+
+        cm_node->ird_size = conn_ird;
+        cm_node->ord_size = conn_ord;
+}
+
 /**
  * cm_build_mpa_frame - build a MPA V1 frame or MPA V2 frame
  */
@@ -557,11 +602,13 @@ static void build_mpa_v2(struct nes_cm_node *cm_node,
         mpa_frame->priv_data_len += htons(IETF_RTR_MSG_SIZE);
 
         /* initialize RTR msg */
-        ctrl_ird = (cm_node->ird_size > IETF_NO_IRD_ORD) ?
-                            IETF_NO_IRD_ORD : cm_node->ird_size;
-        ctrl_ord = (cm_node->ord_size > IETF_NO_IRD_ORD) ?
-                            IETF_NO_IRD_ORD : cm_node->ord_size;
-
+        if (cm_node->mpav2_ird_ord == IETF_NO_IRD_ORD) {
+                ctrl_ird = IETF_NO_IRD_ORD;
+                ctrl_ord = IETF_NO_IRD_ORD;
+        } else {
+                ctrl_ird = cm_node->ird_size & IETF_NO_IRD_ORD;
+                ctrl_ord = cm_node->ord_size & IETF_NO_IRD_ORD;
+        }
         ctrl_ird |= IETF_PEER_TO_PEER;
         ctrl_ird |= IETF_FLPDU_ZERO_LEN;
 
@@ -1409,8 +1456,9 @@ static struct nes_cm_node *make_cm_node(struct nes_cm_core *cm_core,
 
         cm_node->mpa_frame_rev = mpa_version;
         cm_node->send_rdma0_op = SEND_RDMA_READ_ZERO;
-        cm_node->ird_size = IETF_NO_IRD_ORD;
-        cm_node->ord_size = IETF_NO_IRD_ORD;
+        cm_node->mpav2_ird_ord = 0;
+        cm_node->ird_size = 0;
+        cm_node->ord_size = 0;
 
         nes_debug(NES_DBG_CM, "Make node addresses : loc = %pI4:%x, rem = %pI4:%x\n",
                   &cm_node->loc_addr, cm_node->loc_port,
@@ -3027,11 +3075,11 @@ int nes_accept(struct iw_cm_id *cm_id, struct iw_cm_conn_param *conn_param)
                 rem_ref_cm_node(cm_node->cm_core, cm_node);
                 return -ECONNRESET;
         }
-
         /* associate the node with the QP */
         nesqp->cm_node = (void *)cm_node;
         cm_node->nesqp = nesqp;
 
+
         nes_debug(NES_DBG_CM, "QP%u, cm_node=%p, jiffies = %lu listener = %p\n",
                 nesqp->hwqp.qp_id, cm_node, jiffies, cm_node->listener);
         atomic_inc(&cm_accepts);
@@ -3054,6 +3102,11 @@ int nes_accept(struct iw_cm_id *cm_id, struct iw_cm_conn_param *conn_param)
         if (cm_node->mpa_frame_rev == IETF_MPA_V1)
                 mpa_frame_offset = 4;
 
+        if (cm_node->mpa_frame_rev == IETF_MPA_V1 ||
+                        cm_node->mpav2_ird_ord == IETF_NO_IRD_ORD) {
+                record_ird_ord(cm_node, (u16)conn_param->ird, (u16)conn_param->ord);
+        }