/*
 * Copyright (c) 2014, 2015, 2016, 2017 Nicira, Inc.
 * Copyright (c) 2019 Mellanox Technologies, Ltd.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#include <config.h>

#include <rte_flow.h>

#include "cmap.h"
#include "dpif-netdev.h"
#include "netdev-offload-provider.h"
#include "netdev-provider.h"
#include "openvswitch/match.h"
#include "openvswitch/vlog.h"
#include "packets.h"
#include "uuid.h"

VLOG_DEFINE_THIS_MODULE(netdev_offload_dpdk);

/* Thread-safety
 * =============
 *
 * Below API is NOT thread safe in following terms:
 *
 *  - The caller must be sure that none of these functions will be called
 *    simultaneously.  Even for different 'netdev's.
 *
 *  - The caller must be sure that 'netdev' will not be destructed/deallocated.
 *
 *  - The caller must be sure that 'netdev' configuration will not be changed.
 *    For example, simultaneous call of 'netdev_reconfigure()' for the same
 *    'netdev' is forbidden.
 *
 * For current implementation all above restrictions could be fulfilled by
 * taking the datapath 'port_mutex' in lib/dpif-netdev.c.  */

/*
 * A mapping from ufid to dpdk rte_flow.
 */
static struct cmap ufid_to_rte_flow = CMAP_INITIALIZER;

struct ufid_to_rte_flow_data {
    struct cmap_node node;
    ovs_u128 ufid;
    struct rte_flow *rte_flow;
};

/* Find rte_flow with @ufid. */
static struct rte_flow *
ufid_to_rte_flow_find(const ovs_u128 *ufid)
{
    size_t hash = hash_bytes(ufid, sizeof *ufid, 0);
    struct ufid_to_rte_flow_data *data;

    CMAP_FOR_EACH_WITH_HASH (data, node, hash, &ufid_to_rte_flow) {
        if (ovs_u128_equals(*ufid, data->ufid)) {
            return data->rte_flow;
        }
    }

    return NULL;
}

static inline void
ufid_to_rte_flow_associate(const ovs_u128 *ufid,
                           struct rte_flow *rte_flow)
{
    size_t hash = hash_bytes(ufid, sizeof *ufid, 0);
    struct ufid_to_rte_flow_data *data = xzalloc(sizeof *data);

    /*
     * We should not simply overwrite an existing rte flow.
     * We should have deleted it first before re-adding it.
     * Thus, if following assert triggers, something is wrong:
     * the rte_flow is not destroyed.
     */
    ovs_assert(ufid_to_rte_flow_find(ufid) == NULL);

    data->ufid = *ufid;
    data->rte_flow = rte_flow;

    cmap_insert(&ufid_to_rte_flow,
                CONST_CAST(struct cmap_node *, &data->node), hash);
}

static inline void
ufid_to_rte_flow_disassociate(const ovs_u128 *ufid)
{
    size_t hash = hash_bytes(ufid, sizeof *ufid, 0);
    struct ufid_to_rte_flow_data *data;

    CMAP_FOR_EACH_WITH_HASH (data, node, hash, &ufid_to_rte_flow) {
        if (ovs_u128_equals(*ufid, data->ufid)) {
            cmap_remove(&ufid_to_rte_flow,
                        CONST_CAST(struct cmap_node *, &data->node), hash);
            ovsrcu_postpone(free, data);
            return;
        }
    }

    VLOG_WARN("ufid "UUID_FMT" is not associated with an rte flow\n",
              UUID_ARGS((struct uuid *) ufid));
}

/*
 * To avoid individual xrealloc calls for each new element, a 'curent_max'
 * is used to keep track of current allocated number of elements. Starts
 * by 8 and doubles on each xrealloc call.
 */
struct flow_patterns {
    struct rte_flow_item *items;
    int cnt;
    int current_max;
};

struct flow_actions {
    struct rte_flow_action *actions;
    int cnt;
    int current_max;
};

static void
dump_flow_pattern(struct rte_flow_item *item)
{
    struct ds s;

    if (!VLOG_IS_DBG_ENABLED() || item->type == RTE_FLOW_ITEM_TYPE_END) {
        return;
    }

    ds_init(&s);

    if (item->type == RTE_FLOW_ITEM_TYPE_ETH) {
        const struct rte_flow_item_eth *eth_spec = item->spec;
        const struct rte_flow_item_eth *eth_mask = item->mask;

        ds_put_cstr(&s, "rte flow eth pattern:\n");
        if (eth_spec) {
            ds_put_format(&s,
                          "  Spec: src="ETH_ADDR_FMT", dst="ETH_ADDR_FMT", "
                          "type=0x%04" PRIx16"\n",
                          ETH_ADDR_BYTES_ARGS(eth_spec->src.addr_bytes),
                          ETH_ADDR_BYTES_ARGS(eth_spec->dst.addr_bytes),
                          ntohs(eth_spec->type));
        } else {
            ds_put_cstr(&s, "  Spec = null\n");
        }
        if (eth_mask) {
            ds_put_format(&s,
                          "  Mask: src="ETH_ADDR_FMT", dst="ETH_ADDR_FMT", "
                          "type=0x%04"PRIx16"\n",
                          ETH_ADDR_BYTES_ARGS(eth_mask->src.addr_bytes),
                          ETH_ADDR_BYTES_ARGS(eth_mask->dst.addr_bytes),
                          ntohs(eth_mask->type));
        } else {
            ds_put_cstr(&s, "  Mask = null\n");
        }
    }

    if (item->type == RTE_FLOW_ITEM_TYPE_VLAN) {
        const struct rte_flow_item_vlan *vlan_spec = item->spec;
        const struct rte_flow_item_vlan *vlan_mask = item->mask;

        ds_put_cstr(&s, "rte flow vlan pattern:\n");
        if (vlan_spec) {
            ds_put_format(&s,
                          "  Spec: inner_type=0x%"PRIx16", tci=0x%"PRIx16"\n",
                          ntohs(vlan_spec->inner_type), ntohs(vlan_spec->tci));
        } else {
            ds_put_cstr(&s, "  Spec = null\n");
        }

        if (vlan_mask) {
            ds_put_format(&s,
                          "  Mask: inner_type=0x%"PRIx16", tci=0x%"PRIx16"\n",
                          ntohs(vlan_mask->inner_type), ntohs(vlan_mask->tci));
        } else {
            ds_put_cstr(&s, "  Mask = null\n");
        }
    }

    if (item->type == RTE_FLOW_ITEM_TYPE_IPV4) {
        const struct rte_flow_item_ipv4 *ipv4_spec = item->spec;
        const struct rte_flow_item_ipv4 *ipv4_mask = item->mask;

        ds_put_cstr(&s, "rte flow ipv4 pattern:\n");
        if (ipv4_spec) {
            ds_put_format(&s,
                          "  Spec: tos=0x%"PRIx8", ttl=%"PRIx8
                          ", proto=0x%"PRIx8
                          ", src="IP_FMT", dst="IP_FMT"\n",
                          ipv4_spec->hdr.type_of_service,
                          ipv4_spec->hdr.time_to_live,
                          ipv4_spec->hdr.next_proto_id,
                          IP_ARGS(ipv4_spec->hdr.src_addr),
                          IP_ARGS(ipv4_spec->hdr.dst_addr));
        } else {
            ds_put_cstr(&s, "  Spec = null\n");
        }
        if (ipv4_mask) {
            ds_put_format(&s,
                          "  Mask: tos=0x%"PRIx8", ttl=%"PRIx8
                          ", proto=0x%"PRIx8
                          ", src="IP_FMT", dst="IP_FMT"\n",
                          ipv4_mask->hdr.type_of_service,
                          ipv4_mask->hdr.time_to_live,
                          ipv4_mask->hdr.next_proto_id,
                          IP_ARGS(ipv4_mask->hdr.src_addr),
                          IP_ARGS(ipv4_mask->hdr.dst_addr));
        } else {
            ds_put_cstr(&s, "  Mask = null\n");
        }
    }

    if (item->type == RTE_FLOW_ITEM_TYPE_UDP) {
        const struct rte_flow_item_udp *udp_spec = item->spec;
        const struct rte_flow_item_udp *udp_mask = item->mask;

        ds_put_cstr(&s, "rte flow udp pattern:\n");
        if (udp_spec) {
            ds_put_format(&s,
                          "  Spec: src_port=%"PRIu16", dst_port=%"PRIu16"\n",
                          ntohs(udp_spec->hdr.src_port),
                          ntohs(udp_spec->hdr.dst_port));
        } else {
            ds_put_cstr(&s, "  Spec = null\n");
        }
        if (udp_mask) {
            ds_put_format(&s,
                          "  Mask: src_port=0x%"PRIx16
                          ", dst_port=0x%"PRIx16"\n",
                          ntohs(udp_mask->hdr.src_port),
                          ntohs(udp_mask->hdr.dst_port));
        } else {
            ds_put_cstr(&s, "  Mask = null\n");
        }
    }

    if (item->type == RTE_FLOW_ITEM_TYPE_SCTP) {
        const struct rte_flow_item_sctp *sctp_spec = item->spec;
        const struct rte_flow_item_sctp *sctp_mask = item->mask;

        ds_put_cstr(&s, "rte flow sctp pattern:\n");
        if (sctp_spec) {
            ds_put_format(&s,
                          "  Spec: src_port=%"PRIu16", dst_port=%"PRIu16"\n",
                          ntohs(sctp_spec->hdr.src_port),
                          ntohs(sctp_spec->hdr.dst_port));
        } else {
            ds_put_cstr(&s, "  Spec = null\n");
        }
        if (sctp_mask) {
            ds_put_format(&s,
                          "  Mask: src_port=0x%"PRIx16
                          ", dst_port=0x%"PRIx16"\n",
                          ntohs(sctp_mask->hdr.src_port),
                          ntohs(sctp_mask->hdr.dst_port));
        } else {
            ds_put_cstr(&s, "  Mask = null\n");
        }
    }

    if (item->type == RTE_FLOW_ITEM_TYPE_ICMP) {
        const struct rte_flow_item_icmp *icmp_spec = item->spec;
        const struct rte_flow_item_icmp *icmp_mask = item->mask;

        ds_put_cstr(&s, "rte flow icmp pattern:\n");
        if (icmp_spec) {
            ds_put_format(&s,
                          "  Spec: icmp_type=%"PRIu8", icmp_code=%"PRIu8"\n",
                          icmp_spec->hdr.icmp_type,
                          icmp_spec->hdr.icmp_code);
        } else {
            ds_put_cstr(&s, "  Spec = null\n");
        }
        if (icmp_mask) {
            ds_put_format(&s,
                          "  Mask: icmp_type=0x%"PRIx8
                          ", icmp_code=0x%"PRIx8"\n",
                          icmp_spec->hdr.icmp_type,
                          icmp_spec->hdr.icmp_code);
        } else {
            ds_put_cstr(&s, "  Mask = null\n");
        }
    }

    if (item->type == RTE_FLOW_ITEM_TYPE_TCP) {
        const struct rte_flow_item_tcp *tcp_spec = item->spec;
        const struct rte_flow_item_tcp *tcp_mask = item->mask;

        ds_put_cstr(&s, "rte flow tcp pattern:\n");
        if (tcp_spec) {
            ds_put_format(&s,
                          "  Spec: src_port=%"PRIu16", dst_port=%"PRIu16
                          ", data_off=0x%"PRIx8", tcp_flags=0x%"PRIx8"\n",
                          ntohs(tcp_spec->hdr.src_port),
                          ntohs(tcp_spec->hdr.dst_port),
                          tcp_spec->hdr.data_off,
                          tcp_spec->hdr.tcp_flags);
        } else {
            ds_put_cstr(&s, "  Spec = null\n");
        }
        if (tcp_mask) {
            ds_put_format(&s,
                          "  Mask: src_port=%"PRIx16", dst_port=%"PRIx16
                          ", data_off=0x%"PRIx8", tcp_flags=0x%"PRIx8"\n",
                          ntohs(tcp_mask->hdr.src_port),
                          ntohs(tcp_mask->hdr.dst_port),
                          tcp_mask->hdr.data_off,
                          tcp_mask->hdr.tcp_flags);
        } else {
            ds_put_cstr(&s, "  Mask = null\n");
        }
    }

    VLOG_DBG("%s", ds_cstr(&s));
    ds_destroy(&s);
}

static void
add_flow_pattern(struct flow_patterns *patterns, enum rte_flow_item_type type,
                 const void *spec, const void *mask)
{
    int cnt = patterns->cnt;

    if (cnt == 0) {
        patterns->current_max = 8;
        patterns->items = xcalloc(patterns->current_max,
                                  sizeof *patterns->items);
    } else if (cnt == patterns->current_max) {
        patterns->current_max *= 2;
        patterns->items = xrealloc(patterns->items, patterns->current_max *
                                   sizeof *patterns->items);
    }

    patterns->items[cnt].type = type;
    patterns->items[cnt].spec = spec;
    patterns->items[cnt].mask = mask;
    patterns->items[cnt].last = NULL;
    dump_flow_pattern(&patterns->items[cnt]);
    patterns->cnt++;
}

static void
add_flow_action(struct flow_actions *actions, enum rte_flow_action_type type,
                const void *conf)
{
    int cnt = actions->cnt;

    if (cnt == 0) {
        actions->current_max = 8;
        actions->actions = xcalloc(actions->current_max,
                                   sizeof *actions->actions);
    } else if (cnt == actions->current_max) {
        actions->current_max *= 2;
        actions->actions = xrealloc(actions->actions, actions->current_max *
                                    sizeof *actions->actions);
    }

    actions->actions[cnt].type = type;
    actions->actions[cnt].conf = conf;
    actions->cnt++;
}

struct action_rss_data {
    struct rte_flow_action_rss conf;
    uint16_t queue[0];
};

static struct action_rss_data *
add_flow_rss_action(struct flow_actions *actions,
                    struct netdev *netdev)
{
    int i;
    struct action_rss_data *rss_data;

    rss_data = xmalloc(sizeof *rss_data +
                       netdev_n_rxq(netdev) * sizeof rss_data->queue[0]);
    *rss_data = (struct action_rss_data) {
        .conf = (struct rte_flow_action_rss) {
            .func = RTE_ETH_HASH_FUNCTION_DEFAULT,
            .level = 0,
            .types = 0,
            .queue_num = netdev_n_rxq(netdev),
            .queue = rss_data->queue,
            .key_len = 0,
            .key  = NULL
        },
    };

    /* Override queue array with default. */
    for (i = 0; i < netdev_n_rxq(netdev); i++) {
       rss_data->queue[i] = i;
    }

    add_flow_action(actions, RTE_FLOW_ACTION_TYPE_RSS, &rss_data->conf);

    return rss_data;
}

static int
netdev_offload_dpdk_add_flow(struct netdev *netdev,
                             const struct match *match,
                             struct nlattr *nl_actions OVS_UNUSED,
                             size_t actions_len OVS_UNUSED,
                             const ovs_u128 *ufid,
                             struct offload_info *info)
{
    const struct rte_flow_attr flow_attr = {
        .group = 0,
        .priority = 0,
        .ingress = 1,
        .egress = 0
    };
    struct flow_patterns patterns = { .items = NULL, .cnt = 0 };
    struct flow_actions actions = { .actions = NULL, .cnt = 0 };
    struct rte_flow *flow;
    struct rte_flow_error error;
    uint8_t proto = 0;
    int ret = 0;
    struct flow_items {
        struct rte_flow_item_eth  eth;
        struct rte_flow_item_vlan vlan;
        struct rte_flow_item_ipv4 ipv4;
        union {
            struct rte_flow_item_tcp  tcp;
            struct rte_flow_item_udp  udp;
            struct rte_flow_item_sctp sctp;
            struct rte_flow_item_icmp icmp;
        };
    } spec, mask;

    memset(&spec, 0, sizeof spec);
    memset(&mask, 0, sizeof mask);

    /* Eth */
    if (match->wc.masks.dl_type ||
        !eth_addr_is_zero(match->wc.masks.dl_src) ||
        !eth_addr_is_zero(match->wc.masks.dl_dst)) {
        memcpy(&spec.eth.dst, &match->flow.dl_dst, sizeof spec.eth.dst);
        memcpy(&spec.eth.src, &match->flow.dl_src, sizeof spec.eth.src);
        spec.eth.type = match->flow.dl_type;

        memcpy(&mask.eth.dst, &match->wc.masks.dl_dst, sizeof mask.eth.dst);
        memcpy(&mask.eth.src, &match->wc.masks.dl_src, sizeof mask.eth.src);
        mask.eth.type = match->wc.masks.dl_type;

        add_flow_pattern(&patterns, RTE_FLOW_ITEM_TYPE_ETH,
                         &spec.eth, &mask.eth);
    }

    /* VLAN */
    if (match->wc.masks.vlans[0].tci && match->flow.vlans[0].tci) {
        spec.vlan.tci  = match->flow.vlans[0].tci & ~htons(VLAN_CFI);
        mask.vlan.tci  = match->wc.masks.vlans[0].tci & ~htons(VLAN_CFI);

        /* Match any protocols. */
        mask.vlan.inner_type = 0;

        add_flow_pattern(&patterns, RTE_FLOW_ITEM_TYPE_VLAN,
                         &spec.vlan, &mask.vlan);
    }

    /* IP v4 */
    if (match->flow.dl_type == htons(ETH_TYPE_IP)) {
        spec.ipv4.hdr.type_of_service = match->flow.nw_tos;
        spec.ipv4.hdr.time_to_live    = match->flow.nw_ttl;
        spec.ipv4.hdr.next_proto_id   = match->flow.nw_proto;
        spec.ipv4.hdr.src_addr        = match->flow.nw_src;
        spec.ipv4.hdr.dst_addr        = match->flow.nw_dst;

        mask.ipv4.hdr.type_of_service = match->wc.masks.nw_tos;
        mask.ipv4.hdr.time_to_live    = match->wc.masks.nw_ttl;
        mask.ipv4.hdr.next_proto_id   = match->wc.masks.nw_proto;
        mask.ipv4.hdr.src_addr        = match->wc.masks.nw_src;
        mask.ipv4.hdr.dst_addr        = match->wc.masks.nw_dst;

        add_flow_pattern(&patterns, RTE_FLOW_ITEM_TYPE_IPV4,
                         &spec.ipv4, &mask.ipv4);

        /* Save proto for L4 protocol setup. */
        proto = spec.ipv4.hdr.next_proto_id &
                mask.ipv4.hdr.next_proto_id;
    }

    if (proto != IPPROTO_ICMP && proto != IPPROTO_UDP  &&
        proto != IPPROTO_SCTP && proto != IPPROTO_TCP  &&
        (match->wc.masks.tp_src ||
         match->wc.masks.tp_dst ||
         match->wc.masks.tcp_flags)) {
        VLOG_DBG("L4 Protocol (%u) not supported", proto);
        ret = -1;
        goto out;
    }

    if ((match->wc.masks.tp_src && match->wc.masks.tp_src != OVS_BE16_MAX) ||
        (match->wc.masks.tp_dst && match->wc.masks.tp_dst != OVS_BE16_MAX)) {
        ret = -1;
        goto out;
    }

    switch (proto) {
    case IPPROTO_TCP:
        spec.tcp.hdr.src_port  = match->flow.tp_src;
        spec.tcp.hdr.dst_port  = match->flow.tp_dst;
        spec.tcp.hdr.data_off  = ntohs(match->flow.tcp_flags) >> 8;
        spec.tcp.hdr.tcp_flags = ntohs(match->flow.tcp_flags) & 0xff;

        mask.tcp.hdr.src_port  = match->wc.masks.tp_src;
        mask.tcp.hdr.dst_port  = match->wc.masks.tp_dst;
        mask.tcp.hdr.data_off  = ntohs(match->wc.masks.tcp_flags) >> 8;
        mask.tcp.hdr.tcp_flags = ntohs(match->wc.masks.tcp_flags) & 0xff;

        add_flow_pattern(&patterns, RTE_FLOW_ITEM_TYPE_TCP,
                         &spec.tcp, &mask.tcp);

        /* proto == TCP and ITEM_TYPE_TCP, thus no need for proto match. */
        mask.ipv4.hdr.next_proto_id = 0;
        break;

    case IPPROTO_UDP:
        spec.udp.hdr.src_port = match->flow.tp_src;
        spec.udp.hdr.dst_port = match->flow.tp_dst;

        mask.udp.hdr.src_port = match->wc.masks.tp_src;
        mask.udp.hdr.dst_port = match->wc.masks.tp_dst;

        add_flow_pattern(&patterns, RTE_FLOW_ITEM_TYPE_UDP,
                         &spec.udp, &mask.udp);

        /* proto == UDP and ITEM_TYPE_UDP, thus no need for proto match. */
        mask.ipv4.hdr.next_proto_id = 0;
        break;

    case IPPROTO_SCTP:
        spec.sctp.hdr.src_port = match->flow.tp_src;
        spec.sctp.hdr.dst_port = match->flow.tp_dst;

        mask.sctp.hdr.src_port = match->wc.masks.tp_src;
        mask.sctp.hdr.dst_port = match->wc.masks.tp_dst;

        add_flow_pattern(&patterns, RTE_FLOW_ITEM_TYPE_SCTP,
                         &spec.sctp, &mask.sctp);

        /* proto == SCTP and ITEM_TYPE_SCTP, thus no need for proto match. */
        mask.ipv4.hdr.next_proto_id = 0;
        break;

    case IPPROTO_ICMP:
        spec.icmp.hdr.icmp_type = (uint8_t) ntohs(match->flow.tp_src);
        spec.icmp.hdr.icmp_code = (uint8_t) ntohs(match->flow.tp_dst);

        mask.icmp.hdr.icmp_type = (uint8_t) ntohs(match->wc.masks.tp_src);
        mask.icmp.hdr.icmp_code = (uint8_t) ntohs(match->wc.masks.tp_dst);

        add_flow_pattern(&patterns, RTE_FLOW_ITEM_TYPE_ICMP,
                         &spec.icmp, &mask.icmp);

        /* proto == ICMP and ITEM_TYPE_ICMP, thus no need for proto match. */
        mask.ipv4.hdr.next_proto_id = 0;
        break;
    }

    add_flow_pattern(&patterns, RTE_FLOW_ITEM_TYPE_END, NULL, NULL);

    struct rte_flow_action_mark mark;
    struct action_rss_data *rss;

    mark.id = info->flow_mark;
    add_flow_action(&actions, RTE_FLOW_ACTION_TYPE_MARK, &mark);

    rss = add_flow_rss_action(&actions, netdev);
    add_flow_action(&actions, RTE_FLOW_ACTION_TYPE_END, NULL);

    flow = netdev_dpdk_rte_flow_create(netdev, &flow_attr,
                                       patterns.items,
                                       actions.actions, &error);

    free(rss);
    if (!flow) {
        VLOG_ERR("%s: rte flow creat error: %u : message : %s\n",
                 netdev_get_name(netdev), error.type, error.message);
        ret = -1;
        goto out;
    }
    ufid_to_rte_flow_associate(ufid, flow);
    VLOG_DBG("%s: installed flow %p by ufid "UUID_FMT"\n",
             netdev_get_name(netdev), flow, UUID_ARGS((struct uuid *)ufid));

out:
    free(patterns.items);
    free(actions.actions);
    return ret;
}

/*
 * Check if any unsupported flow patterns are specified.
 */
static int
netdev_offload_dpdk_validate_flow(const struct match *match)
{
    struct match match_zero_wc;
    const struct flow *masks = &match->wc.masks;

    /* Create a wc-zeroed version of flow. */
    match_init(&match_zero_wc, &match->flow, &match->wc);

    if (!is_all_zeros(&match_zero_wc.flow.tunnel,
                      sizeof match_zero_wc.flow.tunnel)) {
        goto err;
    }

    if (masks->metadata || masks->skb_priority ||
        masks->pkt_mark || masks->dp_hash) {
        goto err;
    }

    /* recirc id must be zero. */
    if (match_zero_wc.flow.recirc_id) {
        goto err;
    }

    if (masks->ct_state || masks->ct_nw_proto ||
        masks->ct_zone  || masks->ct_mark     ||
        !ovs_u128_is_zero(masks->ct_label)) {
        goto err;
    }

    if (masks->conj_id || masks->actset_output) {
        goto err;
    }

    /* Unsupported L2. */
    if (!is_all_zeros(masks->mpls_lse, sizeof masks->mpls_lse)) {
        goto err;
    }

    /* Unsupported L3. */
    if (masks->ipv6_label || masks->ct_nw_src || masks->ct_nw_dst     ||
        !is_all_zeros(&masks->ipv6_src,    sizeof masks->ipv6_src)    ||
        !is_all_zeros(&masks->ipv6_dst,    sizeof masks->ipv6_dst)    ||
        !is_all_zeros(&masks->ct_ipv6_src, sizeof masks->ct_ipv6_src) ||
        !is_all_zeros(&masks->ct_ipv6_dst, sizeof masks->ct_ipv6_dst) ||
        !is_all_zeros(&masks->nd_target,   sizeof masks->nd_target)   ||
        !is_all_zeros(&masks->nsh,         sizeof masks->nsh)         ||
        !is_all_zeros(&masks->arp_sha,     sizeof masks->arp_sha)     ||
        !is_all_zeros(&masks->arp_tha,     sizeof masks->arp_tha)) {
        goto err;
    }

    /* If fragmented, then don't HW accelerate - for now. */
    if (match_zero_wc.flow.nw_frag) {
        goto err;
    }

    /* Unsupported L4. */
    if (masks->igmp_group_ip4 || masks->ct_tp_src || masks->ct_tp_dst) {
        goto err;
    }

    return 0;

err:
    VLOG_ERR("cannot HW accelerate this flow due to unsupported protocols");
    return -1;
}

static int
netdev_offload_dpdk_destroy_flow(struct netdev *netdev,
                                 const ovs_u128 *ufid,
                                 struct rte_flow *rte_flow)
{
    struct rte_flow_error error;
    int ret = netdev_dpdk_rte_flow_destroy(netdev, rte_flow, &error);

    if (ret == 0) {
        ufid_to_rte_flow_disassociate(ufid);
        VLOG_DBG("%s: removed rte flow %p associated with ufid " UUID_FMT "\n",
                 netdev_get_name(netdev), rte_flow,
                 UUID_ARGS((struct uuid *)ufid));
    } else {
        VLOG_ERR("%s: rte flow destroy error: %u : message : %s\n",
                 netdev_get_name(netdev), error.type, error.message);
    }

    return ret;
}

static int
netdev_offload_dpdk_flow_put(struct netdev *netdev, struct match *match,
                             struct nlattr *actions, size_t actions_len,
                             const ovs_u128 *ufid, struct offload_info *info,
                             struct dpif_flow_stats *stats)
{
    struct rte_flow *rte_flow;
    int ret;

    /*
     * If an old rte_flow exists, it means it's a flow modification.
     * Here destroy the old rte flow first before adding a new one.
     */
    rte_flow = ufid_to_rte_flow_find(ufid);
    if (rte_flow) {
        ret = netdev_offload_dpdk_destroy_flow(netdev, ufid, rte_flow);
        if (ret < 0) {
            return ret;
        }
    }

    ret = netdev_offload_dpdk_validate_flow(match);
    if (ret < 0) {
        return ret;
    }

    if (stats) {
        memset(stats, 0, sizeof *stats);
    }
    return netdev_offload_dpdk_add_flow(netdev, match, actions,
                                        actions_len, ufid, info);
}

static int
netdev_offload_dpdk_flow_del(struct netdev *netdev, const ovs_u128 *ufid,
                             struct dpif_flow_stats *stats)
{
    struct rte_flow *rte_flow = ufid_to_rte_flow_find(ufid);

    if (!rte_flow) {
        return -1;
    }

    if (stats) {
        memset(stats, 0, sizeof *stats);
    }
    return netdev_offload_dpdk_destroy_flow(netdev, ufid, rte_flow);
}

static int
netdev_offload_dpdk_init_flow_api(struct netdev *netdev)
{
    return netdev_dpdk_flow_api_supported(netdev) ? 0 : EOPNOTSUPP;
}

const struct netdev_flow_api netdev_offload_dpdk = {
    .type = "dpdk_flow_api",
    .flow_put = netdev_offload_dpdk_flow_put,
    .flow_del = netdev_offload_dpdk_flow_del,
    .init_flow_api = netdev_offload_dpdk_init_flow_api,
};
