root/drivers/net/ethernet/mellanox/mlxsw/spectrum_flow.c
// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/* Copyright (c) 2017-2020 Mellanox Technologies. All rights reserved */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <net/net_namespace.h>

#include "spectrum.h"

struct mlxsw_sp_flow_block *
mlxsw_sp_flow_block_create(struct mlxsw_sp *mlxsw_sp, struct net *net)
{
        struct mlxsw_sp_flow_block *block;

        block = kzalloc_obj(*block);
        if (!block)
                return NULL;
        INIT_LIST_HEAD(&block->binding_list);
        INIT_LIST_HEAD(&block->mall.list);
        block->mlxsw_sp = mlxsw_sp;
        block->net = net;
        return block;
}

void mlxsw_sp_flow_block_destroy(struct mlxsw_sp_flow_block *block)
{
        WARN_ON(!list_empty(&block->binding_list));
        kfree(block);
}

static struct mlxsw_sp_flow_block_binding *
mlxsw_sp_flow_block_lookup(struct mlxsw_sp_flow_block *block,
                           struct mlxsw_sp_port *mlxsw_sp_port, bool ingress)
{
        struct mlxsw_sp_flow_block_binding *binding;

        list_for_each_entry(binding, &block->binding_list, list)
                if (binding->mlxsw_sp_port == mlxsw_sp_port &&
                    binding->ingress == ingress)
                        return binding;
        return NULL;
}

static bool
mlxsw_sp_flow_block_ruleset_bound(const struct mlxsw_sp_flow_block *block)
{
        return block->ruleset_zero;
}

static int mlxsw_sp_flow_block_bind(struct mlxsw_sp *mlxsw_sp,
                                    struct mlxsw_sp_flow_block *block,
                                    struct mlxsw_sp_port *mlxsw_sp_port,
                                    bool ingress,
                                    struct netlink_ext_ack *extack)
{
        struct mlxsw_sp_flow_block_binding *binding;
        int err;

        if (WARN_ON(mlxsw_sp_flow_block_lookup(block, mlxsw_sp_port, ingress)))
                return -EEXIST;

        if (ingress && block->ingress_blocker_rule_count) {
                NL_SET_ERR_MSG_MOD(extack, "Block cannot be bound to ingress because it contains unsupported rules");
                return -EOPNOTSUPP;
        }

        if (!ingress && block->egress_blocker_rule_count) {
                NL_SET_ERR_MSG_MOD(extack, "Block cannot be bound to egress because it contains unsupported rules");
                return -EOPNOTSUPP;
        }

        err = mlxsw_sp_mall_port_bind(block, mlxsw_sp_port, extack);
        if (err)
                return err;

        binding = kzalloc_obj(*binding);
        if (!binding) {
                err = -ENOMEM;
                goto err_binding_alloc;
        }
        binding->mlxsw_sp_port = mlxsw_sp_port;
        binding->ingress = ingress;

        if (mlxsw_sp_flow_block_ruleset_bound(block)) {
                err = mlxsw_sp_acl_ruleset_bind(mlxsw_sp, block, binding);
                if (err)
                        goto err_ruleset_bind;
        }

        if (ingress)
                block->ingress_binding_count++;
        else
                block->egress_binding_count++;
        list_add(&binding->list, &block->binding_list);
        return 0;

err_ruleset_bind:
        kfree(binding);
err_binding_alloc:
        mlxsw_sp_mall_port_unbind(block, mlxsw_sp_port);

        return err;
}

static int mlxsw_sp_flow_block_unbind(struct mlxsw_sp *mlxsw_sp,
                                      struct mlxsw_sp_flow_block *block,
                                      struct mlxsw_sp_port *mlxsw_sp_port,
                                      bool ingress)
{
        struct mlxsw_sp_flow_block_binding *binding;

        binding = mlxsw_sp_flow_block_lookup(block, mlxsw_sp_port, ingress);
        if (!binding)
                return -ENOENT;

        list_del(&binding->list);

        if (ingress)
                block->ingress_binding_count--;
        else
                block->egress_binding_count--;

        if (mlxsw_sp_flow_block_ruleset_bound(block))
                mlxsw_sp_acl_ruleset_unbind(mlxsw_sp, block, binding);

        kfree(binding);

        mlxsw_sp_mall_port_unbind(block, mlxsw_sp_port);

        return 0;
}

static int mlxsw_sp_flow_block_mall_cb(struct mlxsw_sp_flow_block *flow_block,
                                       struct tc_cls_matchall_offload *f)
{
        struct mlxsw_sp *mlxsw_sp = mlxsw_sp_flow_block_mlxsw_sp(flow_block);

        switch (f->command) {
        case TC_CLSMATCHALL_REPLACE:
                return mlxsw_sp_mall_replace(mlxsw_sp, flow_block, f);
        case TC_CLSMATCHALL_DESTROY:
                mlxsw_sp_mall_destroy(flow_block, f);
                return 0;
        default:
                return -EOPNOTSUPP;
        }
}

static int mlxsw_sp_flow_block_flower_cb(struct mlxsw_sp_flow_block *flow_block,
                                         struct flow_cls_offload *f)
{
        struct mlxsw_sp *mlxsw_sp = mlxsw_sp_flow_block_mlxsw_sp(flow_block);

        switch (f->command) {
        case FLOW_CLS_REPLACE:
                return mlxsw_sp_flower_replace(mlxsw_sp, flow_block, f);
        case FLOW_CLS_DESTROY:
                mlxsw_sp_flower_destroy(mlxsw_sp, flow_block, f);
                return 0;
        case FLOW_CLS_STATS:
                return mlxsw_sp_flower_stats(mlxsw_sp, flow_block, f);
        case FLOW_CLS_TMPLT_CREATE:
                return mlxsw_sp_flower_tmplt_create(mlxsw_sp, flow_block, f);
        case FLOW_CLS_TMPLT_DESTROY:
                mlxsw_sp_flower_tmplt_destroy(mlxsw_sp, flow_block, f);
                return 0;
        default:
                return -EOPNOTSUPP;
        }
}

static int mlxsw_sp_flow_block_cb(enum tc_setup_type type,
                                  void *type_data, void *cb_priv)
{
        struct mlxsw_sp_flow_block *flow_block = cb_priv;

        if (mlxsw_sp_flow_block_disabled(flow_block))
                return -EOPNOTSUPP;

        switch (type) {
        case TC_SETUP_CLSMATCHALL:
                return mlxsw_sp_flow_block_mall_cb(flow_block, type_data);
        case TC_SETUP_CLSFLOWER:
                return mlxsw_sp_flow_block_flower_cb(flow_block, type_data);
        default:
                return -EOPNOTSUPP;
        }
}

static void mlxsw_sp_tc_block_release(void *cb_priv)
{
        struct mlxsw_sp_flow_block *flow_block = cb_priv;

        mlxsw_sp_flow_block_destroy(flow_block);
}

static LIST_HEAD(mlxsw_sp_block_cb_list);

static int mlxsw_sp_setup_tc_block_bind(struct mlxsw_sp_port *mlxsw_sp_port,
                                        struct flow_block_offload *f,
                                        bool ingress)
{
        struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
        struct mlxsw_sp_flow_block *flow_block;
        struct flow_block_cb *block_cb;
        bool register_block = false;
        int err;

        block_cb = flow_block_cb_lookup(f->block, mlxsw_sp_flow_block_cb,
                                        mlxsw_sp);
        if (!block_cb) {
                flow_block = mlxsw_sp_flow_block_create(mlxsw_sp, f->net);
                if (!flow_block)
                        return -ENOMEM;
                block_cb = flow_block_cb_alloc(mlxsw_sp_flow_block_cb,
                                               mlxsw_sp, flow_block,
                                               mlxsw_sp_tc_block_release);
                if (IS_ERR(block_cb)) {
                        mlxsw_sp_flow_block_destroy(flow_block);
                        return PTR_ERR(block_cb);
                }
                register_block = true;
        } else {
                flow_block = flow_block_cb_priv(block_cb);
        }
        flow_block_cb_incref(block_cb);
        err = mlxsw_sp_flow_block_bind(mlxsw_sp, flow_block,
                                       mlxsw_sp_port, ingress, f->extack);
        if (err)
                goto err_block_bind;

        if (ingress)
                mlxsw_sp_port->ing_flow_block = flow_block;
        else
                mlxsw_sp_port->eg_flow_block = flow_block;

        if (register_block) {
                flow_block_cb_add(block_cb, f);
                list_add_tail(&block_cb->driver_list, &mlxsw_sp_block_cb_list);
        }

        return 0;

err_block_bind:
        if (!flow_block_cb_decref(block_cb))
                flow_block_cb_free(block_cb);
        return err;
}

static void mlxsw_sp_setup_tc_block_unbind(struct mlxsw_sp_port *mlxsw_sp_port,
                                           struct flow_block_offload *f,
                                           bool ingress)
{
        struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
        struct mlxsw_sp_flow_block *flow_block;
        struct flow_block_cb *block_cb;
        int err;

        block_cb = flow_block_cb_lookup(f->block, mlxsw_sp_flow_block_cb,
                                        mlxsw_sp);
        if (!block_cb)
                return;

        if (ingress)
                mlxsw_sp_port->ing_flow_block = NULL;
        else
                mlxsw_sp_port->eg_flow_block = NULL;

        flow_block = flow_block_cb_priv(block_cb);
        err = mlxsw_sp_flow_block_unbind(mlxsw_sp, flow_block,
                                         mlxsw_sp_port, ingress);
        if (!err && !flow_block_cb_decref(block_cb)) {
                flow_block_cb_remove(block_cb, f);
                list_del(&block_cb->driver_list);
        }
}

int mlxsw_sp_setup_tc_block_clsact(struct mlxsw_sp_port *mlxsw_sp_port,
                                   struct flow_block_offload *f,
                                   bool ingress)
{
        f->driver_block_list = &mlxsw_sp_block_cb_list;

        switch (f->command) {
        case FLOW_BLOCK_BIND:
                return mlxsw_sp_setup_tc_block_bind(mlxsw_sp_port, f, ingress);
        case FLOW_BLOCK_UNBIND:
                mlxsw_sp_setup_tc_block_unbind(mlxsw_sp_port, f, ingress);
                return 0;
        default:
                return -EOPNOTSUPP;
        }
}