net/mlx5e: Add fragmented memory support for RX multi packet WQE

If the allocation of a linear (physically continuous) MPWQE fails,
we allocate a fragmented MPWQE.

This is implemented via device's UMR (User Memory Registration)
which allows to register multiple memory fragments into ConnectX
hardware as a continuous buffer.
UMR registration is an asynchronous operation and is done via
ICO SQs.

Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 60 insertions, 4 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index b25b429ebabb..942829e6d8ba 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -179,6 +179,7 @@ void mlx5e_update_stats(struct mlx5e_priv *priv)
 	s->rx_csum_sw		= 0;
 	s->rx_wqe_err		= 0;
 	s->rx_mpwqe_filler	= 0;
+	s->rx_mpwqe_frag	= 0;
 	for (i = 0; i < priv->params.num_channels; i++) {
 		rq_stats = &priv->channel[i]->rq.stats;
 
@@ -190,6 +191,7 @@ void mlx5e_update_stats(struct mlx5e_priv *priv)
 		s->rx_csum_sw	+= rq_stats->csum_sw;
 		s->rx_wqe_err   += rq_stats->wqe_err;
 		s->rx_mpwqe_filler += rq_stats->mpwqe_filler;
+		s->rx_mpwqe_frag   += rq_stats->mpwqe_frag;
 
 		for (j = 0; j < priv->params.num_tc; j++) {
 			sq_stats = &priv->channel[i]->sq[j].stats;
@@ -379,7 +381,6 @@ static int mlx5e_create_rq(struct mlx5e_channel *c,
 	for (i = 0; i < wq_sz; i++) {
 		struct mlx5e_rx_wqe *wqe = mlx5_wq_ll_get_wqe(&rq->wq, i);
 
-		wqe->data.lkey       = c->mkey_be;
 		wqe->data.byte_count = cpu_to_be32(byte_count);
 	}
 
@@ -390,6 +391,8 @@ static int mlx5e_create_rq(struct mlx5e_channel *c,
 	rq->channel = c;
 	rq->ix      = c->ix;
 	rq->priv    = c->priv;
+	rq->mkey_be = c->mkey_be;
+	rq->umr_mkey_be = cpu_to_be32(c->priv->umr_mkey.key);
 
 	return 0;
 
@@ -1256,6 +1259,7 @@ static void mlx5e_build_icosq_param(struct mlx5e_priv *priv,
 	mlx5e_build_sq_param_common(priv, param);
 
 	MLX5_SET(wq, wq, log_wq_sz, log_wq_size);
+	MLX5_SET(sqc, sqc, reg_umr, MLX5_CAP_ETH(priv->mdev, reg_umr_sq));
 
 	param->icosq = true;
 }
@@ -1263,7 +1267,7 @@ static void mlx5e_build_icosq_param(struct mlx5e_priv *priv,
 static void mlx5e_build_channel_param(struct mlx5e_priv *priv,
 				      struct mlx5e_channel_param *cparam)
 {
-	u8 icosq_log_wq_sz = 0;
+	u8 icosq_log_wq_sz = MLX5E_PARAMS_MINIMUM_LOG_SQ_SIZE;
 
 	memset(cparam, 0, sizeof(*cparam));
 
@@ -2458,6 +2462,13 @@ void mlx5e_build_default_indir_rqt(struct mlx5_core_dev *mdev,
 		indirection_rqt[i] = i % num_channels;
 }
 
+static bool mlx5e_check_fragmented_striding_rq_cap(struct mlx5_core_dev *mdev)
+{
+	return MLX5_CAP_GEN(mdev, striding_rq) &&
+		MLX5_CAP_GEN(mdev, umr_ptr_rlky) &&
+		MLX5_CAP_ETH(mdev, reg_umr_sq);
+}
+
 static void mlx5e_build_netdev_priv(struct mlx5_core_dev *mdev,
 				    struct net_device *netdev,
 				    int num_channels)
@@ -2466,7 +2477,7 @@ static void mlx5e_build_netdev_priv(struct mlx5_core_dev *mdev,
 
 	priv->params.log_sq_size           =
 		MLX5E_PARAMS_DEFAULT_LOG_SQ_SIZE;
-	priv->params.rq_wq_type = MLX5_CAP_GEN(mdev, striding_rq) ?
+	priv->params.rq_wq_type = mlx5e_check_fragmented_striding_rq_cap(mdev) ?
 		MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ :
 		MLX5_WQ_TYPE_LINKED_LIST;
 
@@ -2639,6 +2650,41 @@ static void mlx5e_destroy_q_counter(struct mlx5e_priv *priv)
 	mlx5_core_dealloc_q_counter(priv->mdev, priv->q_counter);
 }
 
+static int mlx5e_create_umr_mkey(struct mlx5e_priv *priv)
+{
+	struct mlx5_core_dev *mdev = priv->mdev;
+	struct mlx5_create_mkey_mbox_in *in;
+	struct mlx5_mkey_seg *mkc;
+	int inlen = sizeof(*in);
+	u64 npages =
+		mlx5e_get_max_num_channels(mdev) * MLX5_CHANNEL_MAX_NUM_MTTS;
+	int err;
+
+	in = mlx5_vzalloc(inlen);
+	if (!in)
+		return -ENOMEM;
+
+	mkc = &in->seg;
+	mkc->status = MLX5_MKEY_STATUS_FREE;
+	mkc->flags = MLX5_PERM_UMR_EN |
+		     MLX5_PERM_LOCAL_READ |
+		     MLX5_PERM_LOCAL_WRITE |
+		     MLX5_ACCESS_MODE_MTT;
+
+	mkc->qpn_mkey7_0 = cpu_to_be32(0xffffff << 8);
+	mkc->flags_pd = cpu_to_be32(priv->pdn);
+	mkc->len = cpu_to_be64(npages << PAGE_SHIFT);
+	mkc->xlt_oct_size = cpu_to_be32(mlx5e_get_mtt_octw(npages));
+	mkc->log2_page_size = PAGE_SHIFT;
+
+	err = mlx5_core_create_mkey(mdev, &priv->umr_mkey, in, inlen, NULL,
+				    NULL, NULL);
+
+	kvfree(in);
+
+	return err;
+}
+
 static void *mlx5e_create_netdev(struct mlx5_core_dev *mdev)
 {
 	struct net_device *netdev;
@@ -2688,10 +2734,16 @@ static void *mlx5e_create_netdev(struct mlx5_core_dev *mdev)
 		goto err_dealloc_transport_domain;
 	}
 
+	err = mlx5e_create_umr_mkey(priv);
+	if (err) {
+		mlx5_core_err(mdev, "create umr mkey failed, %d\n", err);
+		goto err_destroy_mkey;
+	}
+
 	err = mlx5e_create_tises(priv);
 	if (err) {
 		mlx5_core_warn(mdev, "create tises failed, %d\n", err);
-		goto err_destroy_mkey;
+		goto err_destroy_umr_mkey;
 	}
 
 	err = mlx5e_open_drop_rq(priv);
@@ -2774,6 +2826,9 @@ err_close_drop_rq:
 err_destroy_tises:
 	mlx5e_destroy_tises(priv);
 
+err_destroy_umr_mkey:
+	mlx5_core_destroy_mkey(mdev, &priv->umr_mkey);
+
 err_destroy_mkey:
 	mlx5_core_destroy_mkey(mdev, &priv->mkey);
 
@@ -2812,6 +2867,7 @@ static void mlx5e_destroy_netdev(struct mlx5_core_dev *mdev, void *vpriv)
 	mlx5e_destroy_rqt(priv, MLX5E_INDIRECTION_RQT);
 	mlx5e_close_drop_rq(priv);
 	mlx5e_destroy_tises(priv);
+	mlx5_core_destroy_mkey(priv->mdev, &priv->umr_mkey);
 	mlx5_core_destroy_mkey(priv->mdev, &priv->mkey);
 	mlx5_core_dealloc_transport_domain(priv->mdev, priv->tdn);
 	mlx5_core_dealloc_pd(priv->mdev, priv->pdn);