RDMA/efa: Support QP with unsolicited write w/ imm. receive

Add a new EFA flags attribute for QP creation, and support unsolicited
write with immediate flag. QPs created with this flag set will not
consume receive work requests for incoming RDMA write with immediate.
Expose device capability bit for this feature support.

Reviewed-by: Daniel Kranzdorf <[email protected]>
Reviewed-by: Firas Jahjah <[email protected]>
Signed-off-by: Michael Margolin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Leon Romanovsky <[email protected]>

Author: mrgolin

drivers/infiniband/hw/efa/efa_admin_cmds_defs.h

@@ -110,7 +110,10 @@ struct efa_admin_create_qp_cmd {
 	 *    virtual (IOVA returned by MR registration)
 	 * 1 : rq_virt - If set, RQ ring base address is
 	 *    virtual (IOVA returned by MR registration)
-	 * 7:2 : reserved - MBZ
+	 * 2 : unsolicited_write_recv - If set, work requests
+	 *    will not be consumed for incoming RDMA write with
+	 *    immediate
+	 * 7:3 : reserved - MBZ
 	 */
 	u8 flags;
 
@@ -663,7 +666,9 @@ struct efa_admin_feature_device_attr_desc {
 	 *    polling is supported
 	 * 3 : rdma_write - If set, RDMA Write is supported
 	 *    on TX queues
-	 * 31:4 : reserved - MBZ
+	 * 4 : unsolicited_write_recv - If set, unsolicited
+	 *    write with imm. receive is supported
+	 * 31:5 : reserved - MBZ
 	 */
 	u32 device_caps;
 
@@ -1009,6 +1014,7 @@ struct efa_admin_host_info {
 /* create_qp_cmd */
 #define EFA_ADMIN_CREATE_QP_CMD_SQ_VIRT_MASK                BIT(0)
 #define EFA_ADMIN_CREATE_QP_CMD_RQ_VIRT_MASK                BIT(1)
+#define EFA_ADMIN_CREATE_QP_CMD_UNSOLICITED_WRITE_RECV_MASK BIT(2)
 
 /* modify_qp_cmd */
 #define EFA_ADMIN_MODIFY_QP_CMD_QP_STATE_MASK               BIT(0)
@@ -1044,6 +1050,7 @@ struct efa_admin_host_info {
 #define EFA_ADMIN_FEATURE_DEVICE_ATTR_DESC_RNR_RETRY_MASK   BIT(1)
 #define EFA_ADMIN_FEATURE_DEVICE_ATTR_DESC_DATA_POLLING_128_MASK BIT(2)
 #define EFA_ADMIN_FEATURE_DEVICE_ATTR_DESC_RDMA_WRITE_MASK  BIT(3)
+#define EFA_ADMIN_FEATURE_DEVICE_ATTR_DESC_UNSOLICITED_WRITE_RECV_MASK BIT(4)
 
 /* create_eq_cmd */
 #define EFA_ADMIN_CREATE_EQ_CMD_ENTRY_SIZE_WORDS_MASK       GENMASK(4, 0)

drivers/infiniband/hw/efa/efa_com_cmd.c

@@ -32,6 +32,9 @@ int efa_com_create_qp(struct efa_com_dev *edev,
 			params->rq_depth;
 	create_qp_cmd.uar = params->uarn;
 
+	if (params->unsolicited_write_recv)
+		EFA_SET(&create_qp_cmd.flags, EFA_ADMIN_CREATE_QP_CMD_UNSOLICITED_WRITE_RECV, 1);
+
 	err = efa_com_cmd_exec(aq,
 			       (struct efa_admin_aq_entry *)&create_qp_cmd,
 			       sizeof(create_qp_cmd),

drivers/infiniband/hw/efa/efa_com_cmd.h

@@ -27,6 +27,7 @@ struct efa_com_create_qp_params {
 	u16 pd;
 	u16 uarn;
 	u8 qp_type;
+	u8 unsolicited_write_recv : 1;
 };
 
 struct efa_com_create_qp_result {

drivers/infiniband/hw/efa/efa_verbs.c

@@ -263,6 +263,9 @@ int efa_query_device(struct ib_device *ibdev,
 		if (EFA_DEV_CAP(dev, RDMA_WRITE))
 			resp.device_caps |= EFA_QUERY_DEVICE_CAPS_RDMA_WRITE;
 
+		if (EFA_DEV_CAP(dev, UNSOLICITED_WRITE_RECV))
+			resp.device_caps |= EFA_QUERY_DEVICE_CAPS_UNSOLICITED_WRITE_RECV;
+
 		if (dev->neqs)
 			resp.device_caps |= EFA_QUERY_DEVICE_CAPS_CQ_NOTIFICATIONS;
 
@@ -639,6 +642,7 @@ int efa_create_qp(struct ib_qp *ibqp, struct ib_qp_init_attr *init_attr,
 	struct efa_ibv_create_qp cmd = {};
 	struct efa_qp *qp = to_eqp(ibqp);
 	struct efa_ucontext *ucontext;
+	u16 supported_efa_flags = 0;
 	int err;
 
 	ucontext = rdma_udata_to_drv_context(udata, struct efa_ucontext,
@@ -676,13 +680,23 @@ int efa_create_qp(struct ib_qp *ibqp, struct ib_qp_init_attr *init_attr,
 		goto err_out;
 	}
 
-	if (cmd.comp_mask) {
+	if (cmd.comp_mask || !is_reserved_cleared(cmd.reserved_90)) {
 		ibdev_dbg(&dev->ibdev,
 			  "Incompatible ABI params, unknown fields in udata\n");
 		err = -EINVAL;
 		goto err_out;
 	}
 
+	if (EFA_DEV_CAP(dev, UNSOLICITED_WRITE_RECV))
+		supported_efa_flags |= EFA_CREATE_QP_WITH_UNSOLICITED_WRITE_RECV;
+
+	if (cmd.flags & ~supported_efa_flags) {
+		ibdev_dbg(&dev->ibdev, "Unsupported EFA QP create flags[%#x], supported[%#x]\n",
+			  cmd.flags, supported_efa_flags);
+		err = -EOPNOTSUPP;
+		goto err_out;
+	}
+
 	create_qp_params.uarn = ucontext->uarn;
 	create_qp_params.pd = to_epd(ibqp->pd)->pdn;
 
@@ -722,6 +736,9 @@ int efa_create_qp(struct ib_qp *ibqp, struct ib_qp_init_attr *init_attr,
 		create_qp_params.rq_base_addr = qp->rq_dma_addr;
 	}
 
+	if (cmd.flags & EFA_CREATE_QP_WITH_UNSOLICITED_WRITE_RECV)
+		create_qp_params.unsolicited_write_recv = true;
+
 	err = efa_com_create_qp(&dev->edev, &create_qp_params,
 				&create_qp_resp);
 	if (err)

include/uapi/rdma/efa-abi.h

@@ -85,11 +85,17 @@ enum {
 	EFA_QP_DRIVER_TYPE_SRD = 0,
 };
 
+enum {
+	EFA_CREATE_QP_WITH_UNSOLICITED_WRITE_RECV = 1 << 0,
+};
+
 struct efa_ibv_create_qp {
 	__u32 comp_mask;
 	__u32 rq_ring_size; /* bytes */
 	__u32 sq_ring_size; /* bytes */
 	__u32 driver_qp_type;
+	__u16 flags;
+	__u8 reserved_90[6];
 };
 
 struct efa_ibv_create_qp_resp {
@@ -123,6 +129,7 @@ enum {
 	EFA_QUERY_DEVICE_CAPS_CQ_WITH_SGID     = 1 << 3,
 	EFA_QUERY_DEVICE_CAPS_DATA_POLLING_128 = 1 << 4,
 	EFA_QUERY_DEVICE_CAPS_RDMA_WRITE = 1 << 5,
+	EFA_QUERY_DEVICE_CAPS_UNSOLICITED_WRITE_RECV = 1 << 6,
 };
 
 struct efa_ibv_ex_query_device_resp {