RDMA/mlx5: Expose private query port

Expose a non standard query port via IOCTL that will be used to expose
port attributes that are specific to mlx5 devices.

The new interface receives a port number to query and returns a structure
that contains the available attributes for that port.  This will be used
to fill the gap between pure DEVX use cases and use cases where a kernel
needs to inform userspace about various kernel driver configurations that
userspace must use in order to work correctly.

Flags is used to indicate which fields are valid on return.

MLX5_IB_UAPI_QUERY_PORT_VPORT:
	The vport number of the queered port.

MLX5_IB_UAPI_QUERY_PORT_VPORT_VHCA_ID:
	The VHCA ID of the vport of the queered port.

MLX5_IB_UAPI_QUERY_PORT_VPORT_STEERING_ICM_RX:
	The vport's RX ICM address used for sw steering.

MLX5_IB_UAPI_QUERY_PORT_VPORT_STEERING_ICM_TX:
	The vport's TX ICM address used for sw steering.

MLX5_IB_UAPI_QUERY_PORT_VPORT_REG_C0:
	The metadata used to tag egress packets of the vport.

MLX5_IB_UAPI_QUERY_PORT_ESW_OWNER_VHCA_ID:
	The E-Switch owner vhca id of the vport.

Link: https://lore.kernel.org/r/6e2ef13e5a266a6c037eb0105eb1564c7bb52f23.1618743394.git.leonro@nvidia.com
Reviewed-by: Maor Gottlieb <maorg@nvidia.com>
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/hw/mlx5/std_types.c

@@ -7,6 +7,8 @@
 #include <rdma/mlx5_user_ioctl_cmds.h>
 #include <rdma/mlx5_user_ioctl_verbs.h>
 #include <linux/mlx5/driver.h>
+#include <linux/mlx5/eswitch.h>
+#include <linux/mlx5/vport.h>
 #include "mlx5_ib.h"
 
 #define UVERBS_MODULE_NAME mlx5_ib
@@ -23,6 +25,174 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_PD_QUERY)(
 			      &mpd->pdn, sizeof(mpd->pdn));
 }
 
+static int fill_vport_icm_addr(struct mlx5_core_dev *mdev, u16 vport,
+			       struct mlx5_ib_uapi_query_port *info)
+{
+	u32 out[MLX5_ST_SZ_DW(query_esw_vport_context_out)] = {};
+	u32 in[MLX5_ST_SZ_DW(query_esw_vport_context_in)] = {};
+	bool sw_owner_supp;
+	u64 icm_rx;
+	u64 icm_tx;
+	int err;
+
+	sw_owner_supp = MLX5_CAP_ESW_FLOWTABLE_FDB(mdev, sw_owner) ||
+			MLX5_CAP_ESW_FLOWTABLE_FDB(mdev, sw_owner_v2);
+
+	if (vport == MLX5_VPORT_UPLINK) {
+		icm_rx = MLX5_CAP64_ESW_FLOWTABLE(mdev,
+			sw_steering_uplink_icm_address_rx);
+		icm_tx = MLX5_CAP64_ESW_FLOWTABLE(mdev,
+			sw_steering_uplink_icm_address_tx);
+	} else {
+		MLX5_SET(query_esw_vport_context_in, in, opcode,
+			 MLX5_CMD_OP_QUERY_ESW_VPORT_CONTEXT);
+		MLX5_SET(query_esw_vport_context_in, in, vport_number, vport);
+		MLX5_SET(query_esw_vport_context_in, in, other_vport, true);
+
+		err = mlx5_cmd_exec_inout(mdev, query_esw_vport_context, in,
+					  out);
+
+		if (err)
+			return err;
+
+		icm_rx = MLX5_GET64(
+			query_esw_vport_context_out, out,
+			esw_vport_context.sw_steering_vport_icm_address_rx);
+
+		icm_tx = MLX5_GET64(
+			query_esw_vport_context_out, out,
+			esw_vport_context.sw_steering_vport_icm_address_tx);
+	}
+
+	if (sw_owner_supp && icm_rx) {
+		info->vport_steering_icm_rx = icm_rx;
+		info->flags |=
+			MLX5_IB_UAPI_QUERY_PORT_VPORT_STEERING_ICM_RX;
+	}
+
+	if (sw_owner_supp && icm_tx) {
+		info->vport_steering_icm_tx = icm_tx;
+		info->flags |=
+			MLX5_IB_UAPI_QUERY_PORT_VPORT_STEERING_ICM_TX;
+	}
+
+	return 0;
+}
+
+static int fill_vport_vhca_id(struct mlx5_core_dev *mdev, u16 vport,
+			      struct mlx5_ib_uapi_query_port *info)
+{
+	size_t out_sz = MLX5_ST_SZ_BYTES(query_hca_cap_out);
+	u32 in[MLX5_ST_SZ_DW(query_hca_cap_in)] = {};
+	void *out;
+	int err;
+
+	out = kzalloc(out_sz, GFP_KERNEL);
+	if (!out)
+		return -ENOMEM;
+
+	MLX5_SET(query_hca_cap_in, in, opcode, MLX5_CMD_OP_QUERY_HCA_CAP);
+	MLX5_SET(query_hca_cap_in, in, other_function, true);
+	MLX5_SET(query_hca_cap_in, in, function_id, vport);
+	MLX5_SET(query_hca_cap_in, in, op_mod,
+		 MLX5_SET_HCA_CAP_OP_MOD_GENERAL_DEVICE |
+		 HCA_CAP_OPMOD_GET_CUR);
+
+	err = mlx5_cmd_exec(mdev, in, sizeof(in), out, out_sz);
+	if (err)
+		goto out;
+
+	info->vport_vhca_id = MLX5_GET(query_hca_cap_out, out,
+				       capability.cmd_hca_cap.vhca_id);
+
+	info->flags |= MLX5_IB_UAPI_QUERY_PORT_VPORT_VHCA_ID;
+out:
+	kfree(out);
+	return err;
+}
+
+static int fill_switchdev_info(struct mlx5_ib_dev *dev, u32 port_num,
+			       struct mlx5_ib_uapi_query_port *info)
+{
+	struct mlx5_core_dev *mdev = dev->mdev;
+	struct mlx5_eswitch_rep *rep;
+	int err;
+
+	rep = dev->port[port_num - 1].rep;
+	if (!rep)
+		return -EOPNOTSUPP;
+
+	info->vport = rep->vport;
+	info->flags |= MLX5_IB_UAPI_QUERY_PORT_VPORT;
+
+	if (rep->vport != MLX5_VPORT_UPLINK) {
+		err = fill_vport_vhca_id(mdev, rep->vport, info);
+		if (err)
+			return err;
+	}
+
+	info->esw_owner_vhca_id = MLX5_CAP_GEN(mdev, vhca_id);
+	info->flags |= MLX5_IB_UAPI_QUERY_PORT_ESW_OWNER_VHCA_ID;
+
+	err = fill_vport_icm_addr(mdev, rep->vport, info);
+	if (err)
+		return err;
+
+	if (mlx5_eswitch_vport_match_metadata_enabled(mdev->priv.eswitch)) {
+		info->reg_c0.value = mlx5_eswitch_get_vport_metadata_for_match(
+			mdev->priv.eswitch, rep->vport);
+		info->reg_c0.mask = mlx5_eswitch_get_vport_metadata_mask();
+		info->flags |= MLX5_IB_UAPI_QUERY_PORT_VPORT_REG_C0;
+	}
+
+	return 0;
+}
+
+static int UVERBS_HANDLER(MLX5_IB_METHOD_QUERY_PORT)(
+	struct uverbs_attr_bundle *attrs)
+{
+	struct mlx5_ib_uapi_query_port info = {};
+	struct mlx5_ib_ucontext *c;
+	struct mlx5_ib_dev *dev;
+	u32 port_num;
+	int ret;
+
+	if (uverbs_copy_from(&port_num, attrs,
+			     MLX5_IB_ATTR_QUERY_PORT_PORT_NUM))
+		return -EFAULT;
+
+	c = to_mucontext(ib_uverbs_get_ucontext(attrs));
+	if (IS_ERR(c))
+		return PTR_ERR(c);
+	dev = to_mdev(c->ibucontext.device);
+
+	if (!rdma_is_port_valid(&dev->ib_dev, port_num))
+		return -EINVAL;
+
+	if (mlx5_eswitch_mode(dev->mdev) == MLX5_ESWITCH_OFFLOADS) {
+		ret = fill_switchdev_info(dev, port_num, &info);
+		if (ret)
+			return ret;
+	}
+
+	return uverbs_copy_to_struct_or_zero(attrs, MLX5_IB_ATTR_QUERY_PORT, &info,
+					     sizeof(info));
+}
+
+DECLARE_UVERBS_NAMED_METHOD(
+	MLX5_IB_METHOD_QUERY_PORT,
+	UVERBS_ATTR_PTR_IN(MLX5_IB_ATTR_QUERY_PORT_PORT_NUM,
+			   UVERBS_ATTR_TYPE(u32), UA_MANDATORY),
+	UVERBS_ATTR_PTR_OUT(
+		MLX5_IB_ATTR_QUERY_PORT,
+		UVERBS_ATTR_STRUCT(struct mlx5_ib_uapi_query_port,
+				   reg_c0),
+		UA_MANDATORY));
+
+ADD_UVERBS_METHODS(mlx5_ib_device,
+		   UVERBS_OBJECT_DEVICE,
+		   &UVERBS_METHOD(MLX5_IB_METHOD_QUERY_PORT));
+
 DECLARE_UVERBS_NAMED_METHOD(
 	MLX5_IB_METHOD_PD_QUERY,
 	UVERBS_ATTR_IDR(MLX5_IB_ATTR_QUERY_PD_HANDLE,
@@ -41,5 +211,8 @@ const struct uapi_definition mlx5_ib_std_types_defs[] = {
 	UAPI_DEF_CHAIN_OBJ_TREE(
 		UVERBS_OBJECT_PD,
 		&mlx5_ib_pd),
+	UAPI_DEF_CHAIN_OBJ_TREE(
+		UVERBS_OBJECT_DEVICE,
+		&mlx5_ib_device),
 	{},
 };

include/uapi/rdma/mlx5_user_ioctl_cmds.h

@@ -320,4 +320,13 @@ enum mlx5_ib_pd_methods {
 
 };
 
+enum mlx5_ib_device_methods {
+	MLX5_IB_METHOD_QUERY_PORT = (1U << UVERBS_ID_NS_SHIFT),
+};
+
+enum mlx5_ib_query_port_attrs {
+	MLX5_IB_ATTR_QUERY_PORT_PORT_NUM = (1U << UVERBS_ID_NS_SHIFT),
+	MLX5_IB_ATTR_QUERY_PORT,
+};
+
 #endif

include/uapi/rdma/mlx5_user_ioctl_verbs.h

@@ -83,5 +83,30 @@ enum mlx5_ib_uapi_uar_alloc_type {
 	MLX5_IB_UAPI_UAR_ALLOC_TYPE_NC = 0x1,
 };
 
+enum mlx5_ib_uapi_query_port_flags {
+	MLX5_IB_UAPI_QUERY_PORT_VPORT			= 1 << 0,
+	MLX5_IB_UAPI_QUERY_PORT_VPORT_VHCA_ID		= 1 << 1,
+	MLX5_IB_UAPI_QUERY_PORT_VPORT_STEERING_ICM_RX	= 1 << 2,
+	MLX5_IB_UAPI_QUERY_PORT_VPORT_STEERING_ICM_TX	= 1 << 3,
+	MLX5_IB_UAPI_QUERY_PORT_VPORT_REG_C0		= 1 << 4,
+	MLX5_IB_UAPI_QUERY_PORT_ESW_OWNER_VHCA_ID	= 1 << 5,
+};
+
+struct mlx5_ib_uapi_reg {
+	__u32 value;
+	__u32 mask;
+};
+
+struct mlx5_ib_uapi_query_port {
+	__aligned_u64 flags;
+	__u16 vport;
+	__u16 vport_vhca_id;
+	__u16 esw_owner_vhca_id;
+	__u16 rsvd0;
+	__aligned_u64 vport_steering_icm_rx;
+	__aligned_u64 vport_steering_icm_tx;
+	struct mlx5_ib_uapi_reg reg_c0;
+};
+
 #endif