// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
// Copyright (c) 2021 Mellanox Technologies.

#include "eswitch.h"

/* This struct is used as a key to the hash table and we need it to be packed
 * so hash result is consistent
 */
struct mlx5_vport_key {
        u32 chain;
        u16 prio;
        u16 vport;
        u16 vhca_id;
        struct esw_vport_tbl_namespace *vport_ns;
} __packed;

struct mlx5_vport_table {
        struct hlist_node hlist;
        struct mlx5_flow_table *fdb;
        u32 num_rules;
        struct mlx5_vport_key key;
};

static void
esw_vport_tbl_init(struct mlx5_eswitch *esw, struct esw_vport_tbl_namespace *ns)
{
        if (esw->offloads.encap != DEVLINK_ESWITCH_ENCAP_MODE_NONE)
                ns->flags |= (MLX5_FLOW_TABLE_TUNNEL_EN_REFORMAT |
                              MLX5_FLOW_TABLE_TUNNEL_EN_DECAP);
}

static struct mlx5_flow_table *
esw_vport_tbl_create(struct mlx5_eswitch *esw, struct mlx5_flow_namespace *ns,
                     const struct esw_vport_tbl_namespace *vport_ns)
{
        struct mlx5_flow_table_attr ft_attr = {};
        struct mlx5_flow_table *fdb;

        if (vport_ns->max_num_groups)
                ft_attr.autogroup.max_num_groups = vport_ns->max_num_groups;
        else
                ft_attr.autogroup.max_num_groups = esw->params.large_group_num;
        ft_attr.max_fte = vport_ns->max_fte;
        ft_attr.prio = FDB_PER_VPORT;
        ft_attr.flags = vport_ns->flags;
        fdb = mlx5_create_auto_grouped_flow_table(ns, &ft_attr);
        if (IS_ERR(fdb)) {
                esw_warn(esw->dev, "Failed to create per vport FDB Table err %pe\n",
                         fdb);
        }

        return fdb;
}

static u32 flow_attr_to_vport_key(struct mlx5_eswitch *esw,
                                  struct mlx5_vport_tbl_attr *attr,
                                  struct mlx5_vport_key *key)
{
        key->vport = attr->vport;
        key->chain = attr->chain;
        key->prio = attr->prio;
        key->vhca_id = MLX5_CAP_GEN(esw->dev, vhca_id);
        key->vport_ns  = attr->vport_ns;
        return jhash(key, sizeof(*key), 0);
}

/* caller must hold vports.lock */
static struct mlx5_vport_table *
esw_vport_tbl_lookup(struct mlx5_eswitch *esw, struct mlx5_vport_key *skey, u32 key)
{
        struct mlx5_vport_table *e;

        hash_for_each_possible(esw->fdb_table.offloads.vports.table, e, hlist, key)
                if (!memcmp(&e->key, skey, sizeof(*skey)))
                        return e;

        return NULL;
}

struct mlx5_flow_table *
mlx5_esw_vporttbl_get(struct mlx5_eswitch *esw, struct mlx5_vport_tbl_attr *attr)
{
        struct mlx5_core_dev *dev = esw->dev;
        struct mlx5_flow_namespace *ns;
        struct mlx5_flow_table *fdb;
        struct mlx5_vport_table *e;
        struct mlx5_vport_key skey;
        u32 hkey;

        mutex_lock(&esw->fdb_table.offloads.vports.lock);
        esw_vport_tbl_init(esw, attr->vport_ns);
        hkey = flow_attr_to_vport_key(esw, attr, &skey);
        e = esw_vport_tbl_lookup(esw, &skey, hkey);
        if (e) {
                e->num_rules++;
                goto out;
        }

        e = kzalloc_obj(*e);
        if (!e) {
                fdb = ERR_PTR(-ENOMEM);
                goto err_alloc;
        }

        ns = mlx5_get_flow_namespace(dev, MLX5_FLOW_NAMESPACE_FDB);
        if (!ns) {
                esw_warn(dev, "Failed to get FDB namespace\n");
                fdb = ERR_PTR(-ENOENT);
                goto err_ns;
        }

        fdb = esw_vport_tbl_create(esw, ns, attr->vport_ns);
        if (IS_ERR(fdb))
                goto err_ns;

        e->fdb = fdb;
        e->num_rules = 1;
        e->key = skey;
        hash_add(esw->fdb_table.offloads.vports.table, &e->hlist, hkey);
out:
        mutex_unlock(&esw->fdb_table.offloads.vports.lock);
        return e->fdb;

err_ns:
        kfree(e);
err_alloc:
        mutex_unlock(&esw->fdb_table.offloads.vports.lock);
        return fdb;
}

void
mlx5_esw_vporttbl_put(struct mlx5_eswitch *esw, struct mlx5_vport_tbl_attr *attr)
{
        struct mlx5_vport_table *e;
        struct mlx5_vport_key key;
        u32 hkey;

        mutex_lock(&esw->fdb_table.offloads.vports.lock);
        esw_vport_tbl_init(esw, attr->vport_ns);
        hkey = flow_attr_to_vport_key(esw, attr, &key);
        e = esw_vport_tbl_lookup(esw, &key, hkey);
        if (!e || --e->num_rules)
                goto out;

        hash_del(&e->hlist);
        mlx5_destroy_flow_table(e->fdb);
        kfree(e);
out:
        mutex_unlock(&esw->fdb_table.offloads.vports.lock);
}