1 files changed, 217 insertions, 0 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/pool.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/pool.c
new file mode 100644
index 000000000000..71e8d66fa150
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xsk/pool.c
@@ -0,0 +1,217 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/* Copyright (c) 2019-2020, Mellanox Technologies inc. All rights reserved. */
+
+#include <net/xdp_sock_drv.h>
+#include "pool.h"
+#include "setup.h"
+#include "en/params.h"
+
+static int mlx5e_xsk_map_pool(struct mlx5e_priv *priv,
+			      struct xsk_buff_pool *pool)
+{
+	struct device *dev = mlx5_core_dma_dev(priv->mdev);
+
+	return xsk_pool_dma_map(pool, dev, 0);
+}
+
+static void mlx5e_xsk_unmap_pool(struct mlx5e_priv *priv,
+				 struct xsk_buff_pool *pool)
+{
+	return xsk_pool_dma_unmap(pool, 0);
+}
+
+static int mlx5e_xsk_get_pools(struct mlx5e_xsk *xsk)
+{
+	if (!xsk->pools) {
+		xsk->pools = kcalloc(MLX5E_MAX_NUM_CHANNELS,
+				     sizeof(*xsk->pools), GFP_KERNEL);
+		if (unlikely(!xsk->pools))
+			return -ENOMEM;
+	}
+
+	xsk->refcnt++;
+	xsk->ever_used = true;
+
+	return 0;
+}
+
+static void mlx5e_xsk_put_pools(struct mlx5e_xsk *xsk)
+{
+	if (!--xsk->refcnt) {
+		kfree(xsk->pools);
+		xsk->pools = NULL;
+	}
+}
+
+static int mlx5e_xsk_add_pool(struct mlx5e_xsk *xsk, struct xsk_buff_pool *pool, u16 ix)
+{
+	int err;
+
+	err = mlx5e_xsk_get_pools(xsk);
+	if (unlikely(err))
+		return err;
+
+	xsk->pools[ix] = pool;
+	return 0;
+}
+
+static void mlx5e_xsk_remove_pool(struct mlx5e_xsk *xsk, u16 ix)
+{
+	xsk->pools[ix] = NULL;
+
+	mlx5e_xsk_put_pools(xsk);
+}
+
+static bool mlx5e_xsk_is_pool_sane(struct xsk_buff_pool *pool)
+{
+	return xsk_pool_get_headroom(pool) <= 0xffff &&
+		xsk_pool_get_chunk_size(pool) <= 0xffff;
+}
+
+void mlx5e_build_xsk_param(struct xsk_buff_pool *pool, struct mlx5e_xsk_param *xsk)
+{
+	xsk->headroom = xsk_pool_get_headroom(pool);
+	xsk->chunk_size = xsk_pool_get_chunk_size(pool);
+}
+
+static int mlx5e_xsk_enable_locked(struct mlx5e_priv *priv,
+				   struct xsk_buff_pool *pool, u16 ix)
+{
+	struct mlx5e_params *params = &priv->channels.params;
+	struct mlx5e_xsk_param xsk;
+	struct mlx5e_channel *c;
+	int err;
+
+	if (unlikely(mlx5e_xsk_get_pool(&priv->channels.params, &priv->xsk, ix)))
+		return -EBUSY;
+
+	if (unlikely(!mlx5e_xsk_is_pool_sane(pool)))
+		return -EINVAL;
+
+	err = mlx5e_xsk_map_pool(priv, pool);
+	if (unlikely(err))
+		return err;
+
+	err = mlx5e_xsk_add_pool(&priv->xsk, pool, ix);
+	if (unlikely(err))
+		goto err_unmap_pool;
+
+	mlx5e_build_xsk_param(pool, &xsk);
+
+	if (!test_bit(MLX5E_STATE_OPENED, &priv->state)) {
+		/* XSK objects will be created on open. */
+		goto validate_closed;
+	}
+
+	if (!params->xdp_prog) {
+		/* XSK objects will be created when an XDP program is set,
+		 * and the channels are reopened.
+		 */
+		goto validate_closed;
+	}
+
+	c = priv->channels.c[ix];
+
+	err = mlx5e_open_xsk(priv, params, &xsk, pool, c);
+	if (unlikely(err))
+		goto err_remove_pool;
+
+	mlx5e_activate_xsk(c);
+
+	/* Don't wait for WQEs, because the newer xdpsock sample doesn't provide
+	 * any Fill Ring entries at the setup stage.
+	 */
+
+	err = mlx5e_xsk_redirect_rqt_to_channel(priv, priv->channels.c[ix]);
+	if (unlikely(err))
+		goto err_deactivate;
+
+	return 0;
+
+err_deactivate:
+	mlx5e_deactivate_xsk(c);
+	mlx5e_close_xsk(c);
+
+err_remove_pool:
+	mlx5e_xsk_remove_pool(&priv->xsk, ix);
+
+err_unmap_pool:
+	mlx5e_xsk_unmap_pool(priv, pool);
+
+	return err;
+
+validate_closed:
+	/* Check the configuration in advance, rather than fail at a later stage
+	 * (in mlx5e_xdp_set or on open) and end up with no channels.
+	 */
+	if (!mlx5e_validate_xsk_param(params, &xsk, priv->mdev)) {
+		err = -EINVAL;
+		goto err_remove_pool;
+	}
+
+	return 0;
+}
+
+static int mlx5e_xsk_disable_locked(struct mlx5e_priv *priv, u16 ix)
+{
+	struct xsk_buff_pool *pool = mlx5e_xsk_get_pool(&priv->channels.params,
+						   &priv->xsk, ix);
+	struct mlx5e_channel *c;
+
+	if (unlikely(!pool))
+		return -EINVAL;
+
+	if (!test_bit(MLX5E_STATE_OPENED, &priv->state))
+		goto remove_pool;
+
+	/* XSK RQ and SQ are only created if XDP program is set. */
+	if (!priv->channels.params.xdp_prog)
+		goto remove_pool;
+
+	c = priv->channels.c[ix];
+	mlx5e_xsk_redirect_rqt_to_drop(priv, ix);
+	mlx5e_deactivate_xsk(c);
+	mlx5e_close_xsk(c);
+
+remove_pool:
+	mlx5e_xsk_remove_pool(&priv->xsk, ix);
+	mlx5e_xsk_unmap_pool(priv, pool);
+
+	return 0;
+}
+
+static int mlx5e_xsk_enable_pool(struct mlx5e_priv *priv, struct xsk_buff_pool *pool,
+				 u16 ix)
+{
+	int err;
+
+	mutex_lock(&priv->state_lock);
+	err = mlx5e_xsk_enable_locked(priv, pool, ix);
+	mutex_unlock(&priv->state_lock);
+
+	return err;
+}
+
+static int mlx5e_xsk_disable_pool(struct mlx5e_priv *priv, u16 ix)
+{
+	int err;
+
+	mutex_lock(&priv->state_lock);
+	err = mlx5e_xsk_disable_locked(priv, ix);
+	mutex_unlock(&priv->state_lock);
+
+	return err;
+}
+
+int mlx5e_xsk_setup_pool(struct net_device *dev, struct xsk_buff_pool *pool, u16 qid)
+{
+	struct mlx5e_priv *priv = netdev_priv(dev);
+	struct mlx5e_params *params = &priv->channels.params;
+	u16 ix;
+
+	if (unlikely(!mlx5e_qid_get_ch_if_in_group(params, qid, MLX5E_RQ_GROUP_XSK, &ix)))
+		return -EINVAL;
+
+	return pool ? mlx5e_xsk_enable_pool(priv, pool, ix) :
+		      mlx5e_xsk_disable_pool(priv, ix);
+}