IB/mlx4: Add support for RSS QP

Add support to work with a RSS QP by using an indirection table object
upon QP creation. Other related QP verbs (e.g. modify/destroy/query) were
updated as well for that QP mode.

Notes:
- The RX hash properties are supplied as driver private data.
- The RSS QP port is used on the associated WQs in its indirection
  table. Applying different ports during WQ life time is not allowed.
- The expected RSS QP flow is: create, modify(RST->INIT),
  modify(RST->RTR), destroy.
Signed-off-by: Guy Levi <guyle@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/mlx4/mlx4_ib.h

@@ -46,6 +46,7 @@
 
 #include <linux/mlx4/device.h>
 #include <linux/mlx4/doorbell.h>
+#include <linux/mlx4/qp.h>
 
 #define MLX4_IB_DRV_NAME	"mlx4_ib"
 
@@ -299,6 +300,12 @@ struct mlx4_wqn_range {
 	struct list_head	list;
 };
 
+struct mlx4_ib_rss {
+	unsigned int		base_qpn_tbl_sz;
+	u8			flags;
+	u8			rss_key[MLX4_EN_RSS_KEY_SIZE];
+};
+
 struct mlx4_ib_qp {
 	union {
 		struct ib_qp	ibqp;
@@ -345,6 +352,7 @@ struct mlx4_ib_qp {
 	struct mlx4_wqn_range	*wqn_range;
 	/* Number of RSS QP parents that uses this WQ */
 	u32			rss_usecnt;
+	struct mlx4_ib_rss	*rss_ctx;
 };
 
 struct mlx4_ib_srq {

drivers/infiniband/hw/mlx4/qp.c

@@ -53,6 +53,7 @@ static void mlx4_ib_lock_cqs(struct mlx4_ib_cq *send_cq,
 			     struct mlx4_ib_cq *recv_cq);
 static void mlx4_ib_unlock_cqs(struct mlx4_ib_cq *send_cq,
 			       struct mlx4_ib_cq *recv_cq);
+static int _mlx4_ib_modify_wq(struct ib_wq *ibwq, enum ib_wq_state new_state);
 
 enum {
 	MLX4_IB_ACK_REQ_FREQ	= 8,
@@ -650,6 +651,212 @@ static void mlx4_ib_free_qp_counter(struct mlx4_ib_dev *dev,
 	qp->counter_index = NULL;
 }
 
+static int set_qp_rss(struct mlx4_ib_dev *dev, struct mlx4_ib_rss *rss_ctx,
+		      struct ib_qp_init_attr *init_attr,
+		      struct mlx4_ib_create_qp_rss *ucmd)
+{
+	rss_ctx->base_qpn_tbl_sz = init_attr->rwq_ind_tbl->ind_tbl[0]->wq_num |
+		(init_attr->rwq_ind_tbl->log_ind_tbl_size << 24);
+
+	if ((ucmd->rx_hash_function == MLX4_IB_RX_HASH_FUNC_TOEPLITZ) &&
+	    (dev->dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_RSS_TOP)) {
+		memcpy(rss_ctx->rss_key, ucmd->rx_hash_key,
+		       MLX4_EN_RSS_KEY_SIZE);
+	} else {
+		pr_debug("RX Hash function is not supported\n");
+		return (-EOPNOTSUPP);
+	}
+
+	if ((ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_SRC_IPV4) &&
+	    (ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_DST_IPV4)) {
+		rss_ctx->flags = MLX4_RSS_IPV4;
+	} else if ((ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_SRC_IPV4) ||
+		   (ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_DST_IPV4)) {
+		pr_debug("RX Hash fields_mask is not supported - both IPv4 SRC and DST must be set\n");
+		return (-EOPNOTSUPP);
+	}
+
+	if ((ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_SRC_IPV6) &&
+	    (ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_DST_IPV6)) {
+		rss_ctx->flags |= MLX4_RSS_IPV6;
+	} else if ((ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_SRC_IPV6) ||
+		   (ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_DST_IPV6)) {
+		pr_debug("RX Hash fields_mask is not supported - both IPv6 SRC and DST must be set\n");
+		return (-EOPNOTSUPP);
+	}
+
+	if ((ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_SRC_PORT_UDP) &&
+	    (ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_DST_PORT_UDP)) {
+		if (!(dev->dev->caps.flags & MLX4_DEV_CAP_FLAG_UDP_RSS)) {
+			pr_debug("RX Hash fields_mask for UDP is not supported\n");
+			return (-EOPNOTSUPP);
+		}
+
+		if (rss_ctx->flags & MLX4_RSS_IPV4) {
+			rss_ctx->flags |= MLX4_RSS_UDP_IPV4;
+		} else if (rss_ctx->flags & MLX4_RSS_IPV6) {
+			rss_ctx->flags |= MLX4_RSS_UDP_IPV6;
+		} else {
+			pr_debug("RX Hash fields_mask is not supported - UDP must be set with IPv4 or IPv6\n");
+			return (-EOPNOTSUPP);
+		}
+	} else if ((ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_SRC_PORT_UDP) ||
+		   (ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_DST_PORT_UDP)) {
+		pr_debug("RX Hash fields_mask is not supported - both UDP SRC and DST must be set\n");
+		return (-EOPNOTSUPP);
+	}
+
+	if ((ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_SRC_PORT_TCP) &&
+	    (ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_DST_PORT_TCP)) {
+		if (rss_ctx->flags & MLX4_RSS_IPV4) {
+			rss_ctx->flags |= MLX4_RSS_TCP_IPV4;
+		} else if (rss_ctx->flags & MLX4_RSS_IPV6) {
+			rss_ctx->flags |= MLX4_RSS_TCP_IPV6;
+		} else {
+			pr_debug("RX Hash fields_mask is not supported - TCP must be set with IPv4 or IPv6\n");
+			return (-EOPNOTSUPP);
+		}
+
+	} else if ((ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_SRC_PORT_TCP) ||
+		   (ucmd->rx_hash_fields_mask & MLX4_IB_RX_HASH_DST_PORT_TCP)) {
+		pr_debug("RX Hash fields_mask is not supported - both TCP SRC and DST must be set\n");
+		return (-EOPNOTSUPP);
+	}
+
+	return 0;
+}
+
+static int create_qp_rss(struct mlx4_ib_dev *dev, struct ib_pd *ibpd,
+			 struct ib_qp_init_attr *init_attr,
+			 struct mlx4_ib_create_qp_rss *ucmd,
+			 struct mlx4_ib_qp *qp)
+{
+	int qpn;
+	int err;
+
+	qp->mqp.usage = MLX4_RES_USAGE_USER_VERBS;
+
+	err = mlx4_qp_reserve_range(dev->dev, 1, 1, &qpn, 0, qp->mqp.usage);
+	if (err)
+		return err;
+
+	err = mlx4_qp_alloc(dev->dev, qpn, &qp->mqp);
+	if (err)
+		goto err_qpn;
+
+	mutex_init(&qp->mutex);
+
+	INIT_LIST_HEAD(&qp->gid_list);
+	INIT_LIST_HEAD(&qp->steering_rules);
+
+	qp->mlx4_ib_qp_type = MLX4_IB_QPT_RAW_ETHERTYPE;
+	qp->state = IB_QPS_RESET;
+
+	/* Set dummy send resources to be compatible with HV and PRM */
+	qp->sq_no_prefetch = 1;
+	qp->sq.wqe_cnt = 1;
+	qp->sq.wqe_shift = MLX4_IB_MIN_SQ_STRIDE;
+	qp->buf_size = qp->sq.wqe_cnt << MLX4_IB_MIN_SQ_STRIDE;
+	qp->mtt = (to_mqp(
+		   (struct ib_qp *)init_attr->rwq_ind_tbl->ind_tbl[0]))->mtt;
+
+	qp->rss_ctx = kzalloc(sizeof(*qp->rss_ctx), GFP_KERNEL);
+	if (!qp->rss_ctx) {
+		err = -ENOMEM;
+		goto err_qp_alloc;
+	}
+
+	err = set_qp_rss(dev, qp->rss_ctx, init_attr, ucmd);
+	if (err)
+		goto err;
+
+	return 0;
+
+err:
+	kfree(qp->rss_ctx);
+
+err_qp_alloc:
+	mlx4_qp_remove(dev->dev, &qp->mqp);
+	mlx4_qp_free(dev->dev, &qp->mqp);
+
+err_qpn:
+	mlx4_qp_release_range(dev->dev, qpn, 1);
+	return err;
+}
+
+static struct ib_qp *_mlx4_ib_create_qp_rss(struct ib_pd *pd,
+					    struct ib_qp_init_attr *init_attr,
+					    struct ib_udata *udata)
+{
+	struct mlx4_ib_qp *qp;
+	struct mlx4_ib_create_qp_rss ucmd = {};
+	size_t required_cmd_sz;
+	int err;
+
+	if (!udata) {
+		pr_debug("RSS QP with NULL udata\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (udata->outlen)
+		return ERR_PTR(-EOPNOTSUPP);
+
+	required_cmd_sz = offsetof(typeof(ucmd), reserved1) +
+					sizeof(ucmd.reserved1);
+	if (udata->inlen < required_cmd_sz) {
+		pr_debug("invalid inlen\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (ib_copy_from_udata(&ucmd, udata, min(sizeof(ucmd), udata->inlen))) {
+		pr_debug("copy failed\n");
+		return ERR_PTR(-EFAULT);
+	}
+
+	if (ucmd.comp_mask || ucmd.reserved1)
+		return ERR_PTR(-EOPNOTSUPP);
+
+	if (udata->inlen > sizeof(ucmd) &&
+	    !ib_is_udata_cleared(udata, sizeof(ucmd),
+				 udata->inlen - sizeof(ucmd))) {
+		pr_debug("inlen is not supported\n");
+		return ERR_PTR(-EOPNOTSUPP);
+	}
+
+	if (init_attr->qp_type != IB_QPT_RAW_PACKET) {
+		pr_debug("RSS QP with unsupported QP type %d\n",
+			 init_attr->qp_type);
+		return ERR_PTR(-EOPNOTSUPP);
+	}
+
+	if (init_attr->create_flags) {
+		pr_debug("RSS QP doesn't support create flags\n");
+		return ERR_PTR(-EOPNOTSUPP);
+	}
+
+	if (init_attr->send_cq || init_attr->cap.max_send_wr) {
+		pr_debug("RSS QP with unsupported send attributes\n");
+		return ERR_PTR(-EOPNOTSUPP);
+	}
+
+	qp = kzalloc(sizeof(*qp), GFP_KERNEL);
+	if (!qp)
+		return ERR_PTR(-ENOMEM);
+
+	qp->pri.vid = 0xFFFF;
+	qp->alt.vid = 0xFFFF;
+
+	err = create_qp_rss(to_mdev(pd->device), pd, init_attr, &ucmd, qp);
+	if (err) {
+		kfree(qp);
+		return ERR_PTR(err);
+	}
+
+	qp->ibqp.qp_num = qp->mqp.qpn;
+
+	return &qp->ibqp;
+}
+
 /*
  * This function allocates a WQN from a range which is consecutive and aligned
  * to its size. In case the range is full, then it creates a new range and
@@ -1186,6 +1393,36 @@ static void get_cqs(struct mlx4_ib_qp *qp, enum mlx4_ib_source_type src,
 	}
 }
 
+static void destroy_qp_rss(struct mlx4_ib_dev *dev, struct mlx4_ib_qp *qp)
+{
+	if (qp->state != IB_QPS_RESET) {
+		int i;
+
+		for (i = 0; i < (1 << qp->ibqp.rwq_ind_tbl->log_ind_tbl_size);
+		     i++) {
+			struct ib_wq *ibwq = qp->ibqp.rwq_ind_tbl->ind_tbl[i];
+			struct mlx4_ib_qp *wq =	to_mqp((struct ib_qp *)ibwq);
+
+			mutex_lock(&wq->mutex);
+
+			wq->rss_usecnt--;
+
+			mutex_unlock(&wq->mutex);
+		}
+
+		if (mlx4_qp_modify(dev->dev, NULL, to_mlx4_state(qp->state),
+				   MLX4_QP_STATE_RST, NULL, 0, 0, &qp->mqp))
+			pr_warn("modify QP %06x to RESET failed.\n",
+				qp->mqp.qpn);
+	}
+
+	mlx4_qp_remove(dev->dev, &qp->mqp);
+	mlx4_qp_free(dev->dev, &qp->mqp);
+	mlx4_qp_release_range(dev->dev, qp->mqp.qpn, 1);
+	del_gid_entries(qp);
+	kfree(qp->rss_ctx);
+}
+
 static void destroy_qp_common(struct mlx4_ib_dev *dev, struct mlx4_ib_qp *qp,
 			      enum mlx4_ib_source_type src, int is_user)
 {
@@ -1303,6 +1540,9 @@ static struct ib_qp *_mlx4_ib_create_qp(struct ib_pd *pd,
 	int sup_u_create_flags = MLX4_IB_QP_BLOCK_MULTICAST_LOOPBACK;
 	u16 xrcdn = 0;
 
+	if (init_attr->rwq_ind_tbl)
+		return _mlx4_ib_create_qp_rss(pd, init_attr, udata);
+
 	/*
 	 * We only support LSO, vendor flag1, and multicast loopback blocking,
 	 * and only for kernel UD QPs.
@@ -1444,7 +1684,6 @@ static int _mlx4_ib_destroy_qp(struct ib_qp *qp)
 {
 	struct mlx4_ib_dev *dev = to_mdev(qp->device);
 	struct mlx4_ib_qp *mqp = to_mqp(qp);
-	struct mlx4_ib_pd *pd;
 
 	if (is_qp0(dev, mqp))
 		mlx4_CLOSE_PORT(dev->dev, mqp->port);
@@ -1459,8 +1698,14 @@ static int _mlx4_ib_destroy_qp(struct ib_qp *qp)
 	if (mqp->counter_index)
 		mlx4_ib_free_qp_counter(dev, mqp);
 
+	if (qp->rwq_ind_tbl) {
+		destroy_qp_rss(dev, mqp);
+	} else {
+		struct mlx4_ib_pd *pd;
+
 		pd = get_pd(mqp);
 		destroy_qp_common(dev, mqp, MLX4_IB_QP_SRC, !!pd->ibpd.uobject);
+	}
 
 	if (is_sqp(dev, mqp))
 		kfree(to_msqp(mqp));
@@ -1783,12 +2028,116 @@ static u8 gid_type_to_qpc(enum ib_gid_type gid_type)
 	}
 }
 
+/*
+ * Go over all RSS QP's childes (WQs) and apply their HW state according to
+ * their logic state if the RSS QP is the first RSS QP associated for the WQ.
+ */
+static int bringup_rss_rwqs(struct ib_rwq_ind_table *ind_tbl, u8 port_num)
+{
+	int i;
+	int err;
+
+	for (i = 0; i < (1 << ind_tbl->log_ind_tbl_size); i++) {
+		struct ib_wq *ibwq = ind_tbl->ind_tbl[i];
+		struct mlx4_ib_qp *wq = to_mqp((struct ib_qp *)ibwq);
+
+		mutex_lock(&wq->mutex);
+
+		/* Mlx4_ib restrictions:
+		 * WQ's is associated to a port according to the RSS QP it is
+		 * associates to.
+		 * In case the WQ is associated to a different port by another
+		 * RSS QP, return a failure.
+		 */
+		if ((wq->rss_usecnt > 0) && (wq->port != port_num)) {
+			err = -EINVAL;
+			mutex_unlock(&wq->mutex);
+			break;
+		}
+		wq->port = port_num;
+		if ((wq->rss_usecnt == 0) && (ibwq->state == IB_WQS_RDY)) {
+			err = _mlx4_ib_modify_wq(ibwq, IB_WQS_RDY);
+			if (err) {
+				mutex_unlock(&wq->mutex);
+				break;
+			}
+		}
+		wq->rss_usecnt++;
+
+		mutex_unlock(&wq->mutex);
+	}
+
+	if (i && err) {
+		int j;
+
+		for (j = (i - 1); j >= 0; j--) {
+			struct ib_wq *ibwq = ind_tbl->ind_tbl[j];
+			struct mlx4_ib_qp *wq = to_mqp((struct ib_qp *)ibwq);
+
+			mutex_lock(&wq->mutex);
+
+			if ((wq->rss_usecnt == 1) &&
+			    (ibwq->state == IB_WQS_RDY))
+				if (_mlx4_ib_modify_wq(ibwq, IB_WQS_RESET))
+					pr_warn("failed to reverse WQN=0x%06x\n",
+						ibwq->wq_num);
+			wq->rss_usecnt--;
+
+			mutex_unlock(&wq->mutex);
+		}
+	}
+
+	return err;
+}
+
+static void bring_down_rss_rwqs(struct ib_rwq_ind_table *ind_tbl)
+{
+	int i;
+
+	for (i = 0; i < (1 << ind_tbl->log_ind_tbl_size); i++) {
+		struct ib_wq *ibwq = ind_tbl->ind_tbl[i];
+		struct mlx4_ib_qp *wq = to_mqp((struct ib_qp *)ibwq);
+
+		mutex_lock(&wq->mutex);
+
+		if ((wq->rss_usecnt == 1) && (ibwq->state == IB_WQS_RDY))
+			if (_mlx4_ib_modify_wq(ibwq, IB_WQS_RESET))
+				pr_warn("failed to reverse WQN=%x\n",
+					ibwq->wq_num);
+		wq->rss_usecnt--;
+
+		mutex_unlock(&wq->mutex);
+	}
+}
+
+static void fill_qp_rss_context(struct mlx4_qp_context *context,
+				struct mlx4_ib_qp *qp)
+{
+	struct mlx4_rss_context *rss_context;
+
+	rss_context = (void *)context + offsetof(struct mlx4_qp_context,
+			pri_path) + MLX4_RSS_OFFSET_IN_QPC_PRI_PATH;
+
+	rss_context->base_qpn = cpu_to_be32(qp->rss_ctx->base_qpn_tbl_sz);
+	rss_context->default_qpn =
+		cpu_to_be32(qp->rss_ctx->base_qpn_tbl_sz & 0xffffff);
+	if (qp->rss_ctx->flags & (MLX4_RSS_UDP_IPV4 | MLX4_RSS_UDP_IPV6))
+		rss_context->base_qpn_udp = rss_context->default_qpn;
+	rss_context->flags = qp->rss_ctx->flags;
+	/* Currently support just toeplitz */
+	rss_context->hash_fn = MLX4_RSS_HASH_TOP;
+
+	memcpy(rss_context->rss_key, qp->rss_ctx->rss_key,
+	       MLX4_EN_RSS_KEY_SIZE);
+}
+
 static int __mlx4_ib_modify_qp(void *src, enum mlx4_ib_source_type src_type,
 			       const struct ib_qp_attr *attr, int attr_mask,
 			       enum ib_qp_state cur_state, enum ib_qp_state new_state)
 {
 	struct ib_uobject *ibuobject;
 	struct ib_srq  *ibsrq;
+	struct ib_rwq_ind_table *rwq_ind_tbl;
 	enum ib_qp_type qp_type;
 	struct mlx4_ib_dev *dev;
 	struct mlx4_ib_qp *qp;
@@ -1807,6 +2156,7 @@ static int __mlx4_ib_modify_qp(void *src, enum mlx4_ib_source_type src_type,
 		ibwq	    = (struct ib_wq *)src;
 		ibuobject   = ibwq->uobject;
 		ibsrq	    = NULL;
+		rwq_ind_tbl = NULL;
 		qp_type     = IB_QPT_RAW_PACKET;
 		qp	    = to_mqp((struct ib_qp *)ibwq);
 		dev	    = to_mdev(ibwq->device);
@@ -1817,6 +2167,7 @@ static int __mlx4_ib_modify_qp(void *src, enum mlx4_ib_source_type src_type,
 		ibqp	    = (struct ib_qp *)src;
 		ibuobject   = ibqp->uobject;
 		ibsrq	    = ibqp->srq;
+		rwq_ind_tbl = ibqp->rwq_ind_tbl;
 		qp_type     = ibqp->qp_type;
 		qp	    = to_mqp(ibqp);
 		dev	    = to_mdev(ibqp->device);
@@ -1836,6 +2187,11 @@ static int __mlx4_ib_modify_qp(void *src, enum mlx4_ib_source_type src_type,
 	context->flags = cpu_to_be32((to_mlx4_state(new_state) << 28) |
 				     (to_mlx4_st(dev, qp->mlx4_ib_qp_type) << 16));
 
+	if (rwq_ind_tbl) {
+		fill_qp_rss_context(context, qp);
+		context->flags |= cpu_to_be32(1 << MLX4_RSS_QPC_FLAG_OFFSET);
+	}
+
 	if (!(attr_mask & IB_QP_PATH_MIG_STATE))
 		context->flags |= cpu_to_be32(MLX4_QP_PM_MIGRATED << 11);
 	else {
@@ -1876,9 +2232,11 @@ static int __mlx4_ib_modify_qp(void *src, enum mlx4_ib_source_type src_type,
 			ilog2(dev->dev->caps.max_msg_sz);
 	}
 
+	if (!rwq_ind_tbl) { /* PRM RSS receive side should be left zeros */
 		if (qp->rq.wqe_cnt)
 			context->rq_size_stride = ilog2(qp->rq.wqe_cnt) << 3;
 		context->rq_size_stride |= qp->rq.wqe_shift - 4;
+	}
 
 	if (qp->sq.wqe_cnt)
 		context->sq_size_stride = ilog2(qp->sq.wqe_cnt) << 3;
@@ -2031,8 +2389,14 @@ static int __mlx4_ib_modify_qp(void *src, enum mlx4_ib_source_type src_type,
 		optpar |= MLX4_QP_OPTPAR_ALT_ADDR_PATH;
 	}
 
-	get_cqs(qp, src_type, &send_cq, &recv_cq);
 	context->pd = cpu_to_be32(pd->pdn);
+
+	if (!rwq_ind_tbl) {
+		get_cqs(qp, src_type, &send_cq, &recv_cq);
+	} else { /* Set dummy CQs to be compatible with HV and PRM */
+		send_cq = to_mcq(rwq_ind_tbl->ind_tbl[0]->cq);
+		recv_cq = send_cq;
+	}
 	context->cqn_send = cpu_to_be32(send_cq->mcq.cqn);
 	context->cqn_recv = cpu_to_be32(recv_cq->mcq.cqn);
 	context->params1  = cpu_to_be32(MLX4_IB_ACK_REQ_FREQ << 28);
@@ -2358,6 +2722,11 @@ static int __mlx4_ib_modify_qp(void *src, enum mlx4_ib_source_type src_type,
 	return err;
 }
 
+enum {
+	MLX4_IB_MODIFY_QP_RSS_SUP_ATTR_MSK = (IB_QP_STATE	|
+					      IB_QP_PORT),
+};
+
 static int _mlx4_ib_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 			      int attr_mask, struct ib_udata *udata)
 {
@@ -2388,6 +2757,27 @@ static int _mlx4_ib_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 		goto out;
 	}
 
+	if (ibqp->rwq_ind_tbl) {
+		if (!(((cur_state == IB_QPS_RESET) &&
+		       (new_state == IB_QPS_INIT)) ||
+		      ((cur_state == IB_QPS_INIT)  &&
+		       (new_state == IB_QPS_RTR)))) {
+			pr_debug("qpn 0x%x: RSS QP unsupported transition %d to %d\n",
+				 ibqp->qp_num, cur_state, new_state);
+
+			err = -EOPNOTSUPP;
+			goto out;
+		}
+
+		if (attr_mask & ~MLX4_IB_MODIFY_QP_RSS_SUP_ATTR_MSK) {
+			pr_debug("qpn 0x%x: RSS QP unsupported attribute mask 0x%x for transition %d to %d\n",
+				 ibqp->qp_num, attr_mask, cur_state, new_state);
+
+			err = -EOPNOTSUPP;
+			goto out;
+		}
+	}
+
 	if (mlx4_is_bonded(dev->dev) && (attr_mask & IB_QP_PORT)) {
 		if ((cur_state == IB_QPS_RESET) && (new_state == IB_QPS_INIT)) {
 			if ((ibqp->qp_type == IB_QPT_RC) ||
@@ -2452,9 +2842,18 @@ static int _mlx4_ib_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 		goto out;
 	}
 
+	if (ibqp->rwq_ind_tbl && (new_state == IB_QPS_INIT)) {
+		err = bringup_rss_rwqs(ibqp->rwq_ind_tbl, attr->port_num);
+		if (err)
+			goto out;
+	}
+
 	err = __mlx4_ib_modify_qp(ibqp, MLX4_IB_QP_SRC, attr, attr_mask,
 				  cur_state, new_state);
 
+	if (ibqp->rwq_ind_tbl && err)
+		bring_down_rss_rwqs(ibqp->rwq_ind_tbl);
+
 	if (mlx4_is_bonded(dev->dev) && (attr_mask & IB_QP_PORT))
 		attr->port_num = 1;
 
@@ -3643,6 +4042,9 @@ int mlx4_ib_query_qp(struct ib_qp *ibqp, struct ib_qp_attr *qp_attr, int qp_attr
 	int mlx4_state;
 	int err = 0;
 
+	if (ibqp->rwq_ind_tbl)
+		return -EOPNOTSUPP;
+
 	mutex_lock(&qp->mutex);
 
 	if (qp->state == IB_QPS_RESET) {
@@ -3917,6 +4319,11 @@ int mlx4_ib_modify_wq(struct ib_wq *ibwq, struct ib_wq_attr *wq_attr,
 	if ((new_state == IB_WQS_ERR) && (cur_state == IB_WQS_RESET))
 		return -EINVAL;
 
+	/* Need to protect against the parent RSS which also may modify WQ
+	 * state.
+	 */
+	mutex_lock(&qp->mutex);
+
 	/* Can update HW state only if a RSS QP has already associated to this
 	 * WQ, so we can apply its port on the WQ.
 	 */
@@ -3926,6 +4333,8 @@ int mlx4_ib_modify_wq(struct ib_wq *ibwq, struct ib_wq_attr *wq_attr,
 	if (!err)
 		ibwq->state = new_state;
 
+	mutex_unlock(&qp->mutex);
+
 	return err;
 }
 

include/uapi/rdma/mlx4-abi.h

@@ -95,6 +95,16 @@ struct mlx4_ib_create_srq_resp {
 	__u32	reserved;
 };
 
+struct mlx4_ib_create_qp_rss {
+	__u64   rx_hash_fields_mask;
+	__u8    rx_hash_function;
+	__u8    rx_key_len;
+	__u8    reserved[6];
+	__u8    rx_hash_key[40];
+	__u32   comp_mask;
+	__u32   reserved1;
+};
+
 struct mlx4_ib_create_qp {
 	__u64	buf_addr;
 	__u64	db_addr;
@@ -123,4 +133,27 @@ struct mlx4_ib_create_rwq_ind_tbl_resp {
 	__u32	response_length;
 	__u32	reserved;
 };
+
+/* RX Hash function flags */
+enum mlx4_ib_rx_hash_function_flags {
+	MLX4_IB_RX_HASH_FUNC_TOEPLITZ	= 1 << 0,
+};
+
+/*
+ * RX Hash flags, these flags allows to set which incoming packet's field should
+ * participates in RX Hash. Each flag represent certain packet's field,
+ * when the flag is set the field that is represented by the flag will
+ * participate in RX Hash calculation.
+ */
+enum mlx4_ib_rx_hash_fields {
+	MLX4_IB_RX_HASH_SRC_IPV4	= 1 << 0,
+	MLX4_IB_RX_HASH_DST_IPV4	= 1 << 1,
+	MLX4_IB_RX_HASH_SRC_IPV6	= 1 << 2,
+	MLX4_IB_RX_HASH_DST_IPV6	= 1 << 3,
+	MLX4_IB_RX_HASH_SRC_PORT_TCP	= 1 << 4,
+	MLX4_IB_RX_HASH_DST_PORT_TCP	= 1 << 5,
+	MLX4_IB_RX_HASH_SRC_PORT_UDP	= 1 << 6,
+	MLX4_IB_RX_HASH_DST_PORT_UDP	= 1 << 7
+};
+
 #endif /* MLX4_ABI_USER_H */