Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma

[mirror_ubuntu-bionic-kernel.git] / drivers / net / ethernet / broadcom / bnxt / bnxt_tc.c

/* Broadcom NetXtreme-C/E network driver.
 *
 * Copyright (c) 2017 Broadcom Limited
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation.
 */

#include <linux/netdevice.h>
#include <linux/inetdevice.h>
#include <linux/if_vlan.h>
#include <net/flow_dissector.h>
#include <net/pkt_cls.h>
#include <net/tc_act/tc_gact.h>
#include <net/tc_act/tc_skbedit.h>
#include <net/tc_act/tc_mirred.h>
#include <net/tc_act/tc_vlan.h>

#include "bnxt_hsi.h"
#include "bnxt.h"
#include "bnxt_sriov.h"
#include "bnxt_tc.h"
#include "bnxt_vfr.h"

#ifdef CONFIG_BNXT_FLOWER_OFFLOAD

#define BNXT_FID_INVALID                        0xffff
#define VLAN_TCI(vid, prio)     ((vid) | ((prio) << VLAN_PRIO_SHIFT))

/* Return the dst fid of the func for flow forwarding
 * For PFs: src_fid is the fid of the PF
 * For VF-reps: src_fid the fid of the VF
 */
static u16 bnxt_flow_get_dst_fid(struct bnxt *pf_bp, struct net_device *dev)
{
        struct bnxt *bp;

        /* check if dev belongs to the same switch */
        if (!switchdev_port_same_parent_id(pf_bp->dev, dev)) {
                netdev_info(pf_bp->dev, "dev(ifindex=%d) not on same switch",
                            dev->ifindex);
                return BNXT_FID_INVALID;
        }

        /* Is dev a VF-rep? */
        if (dev != pf_bp->dev)
                return bnxt_vf_rep_get_fid(dev);

        bp = netdev_priv(dev);
        return bp->pf.fw_fid;
}

static int bnxt_tc_parse_redir(struct bnxt *bp,
                               struct bnxt_tc_actions *actions,
                               const struct tc_action *tc_act)
{
        int ifindex = tcf_mirred_ifindex(tc_act);
        struct net_device *dev;
        u16 dst_fid;

        dev = __dev_get_by_index(dev_net(bp->dev), ifindex);
        if (!dev) {
                netdev_info(bp->dev, "no dev for ifindex=%d", ifindex);
                return -EINVAL;
        }

        /* find the FID from dev */
        dst_fid = bnxt_flow_get_dst_fid(bp, dev);
        if (dst_fid == BNXT_FID_INVALID) {
                netdev_info(bp->dev, "can't get fid for ifindex=%d", ifindex);
                return -EINVAL;
        }

        actions->flags |= BNXT_TC_ACTION_FLAG_FWD;
        actions->dst_fid = dst_fid;
        actions->dst_dev = dev;
        return 0;
}

static void bnxt_tc_parse_vlan(struct bnxt *bp,
                               struct bnxt_tc_actions *actions,
                               const struct tc_action *tc_act)
{
        if (tcf_vlan_action(tc_act) == TCA_VLAN_ACT_POP) {
                actions->flags |= BNXT_TC_ACTION_FLAG_POP_VLAN;
        } else if (tcf_vlan_action(tc_act) == TCA_VLAN_ACT_PUSH) {
                actions->flags |= BNXT_TC_ACTION_FLAG_PUSH_VLAN;
                actions->push_vlan_tci = htons(tcf_vlan_push_vid(tc_act));
                actions->push_vlan_tpid = tcf_vlan_push_proto(tc_act);
        }
}

static int bnxt_tc_parse_actions(struct bnxt *bp,
                                 struct bnxt_tc_actions *actions,
                                 struct tcf_exts *tc_exts)
{
        const struct tc_action *tc_act;
        LIST_HEAD(tc_actions);
        int rc;

        if (!tcf_exts_has_actions(tc_exts)) {
                netdev_info(bp->dev, "no actions");
                return -EINVAL;
        }

        tcf_exts_to_list(tc_exts, &tc_actions);
        list_for_each_entry(tc_act, &tc_actions, list) {
                /* Drop action */
                if (is_tcf_gact_shot(tc_act)) {
                        actions->flags |= BNXT_TC_ACTION_FLAG_DROP;
                        return 0; /* don't bother with other actions */
                }

                /* Redirect action */
                if (is_tcf_mirred_egress_redirect(tc_act)) {
                        rc = bnxt_tc_parse_redir(bp, actions, tc_act);
                        if (rc)
                                return rc;
                        continue;
                }

                /* Push/pop VLAN */
                if (is_tcf_vlan(tc_act)) {
                        bnxt_tc_parse_vlan(bp, actions, tc_act);
                        continue;
                }
        }

        return 0;
}

#define GET_KEY(flow_cmd, key_type)                                     \
                skb_flow_dissector_target((flow_cmd)->dissector, key_type,\
                                          (flow_cmd)->key)
#define GET_MASK(flow_cmd, key_type)                                    \
                skb_flow_dissector_target((flow_cmd)->dissector, key_type,\
                                          (flow_cmd)->mask)

static int bnxt_tc_parse_flow(struct bnxt *bp,
                              struct tc_cls_flower_offload *tc_flow_cmd,
                              struct bnxt_tc_flow *flow)
{
        struct flow_dissector *dissector = tc_flow_cmd->dissector;
        u16 addr_type = 0;

        /* KEY_CONTROL and KEY_BASIC are needed for forming a meaningful key */
        if ((dissector->used_keys & BIT(FLOW_DISSECTOR_KEY_CONTROL)) == 0 ||
            (dissector->used_keys & BIT(FLOW_DISSECTOR_KEY_BASIC)) == 0) {
                netdev_info(bp->dev, "cannot form TC key: used_keys = 0x%x",
                            dissector->used_keys);
                return -EOPNOTSUPP;
        }

        if (dissector_uses_key(dissector, FLOW_DISSECTOR_KEY_CONTROL)) {
                struct flow_dissector_key_control *key =
                        GET_KEY(tc_flow_cmd, FLOW_DISSECTOR_KEY_CONTROL);

                addr_type = key->addr_type;
        }

        if (dissector_uses_key(dissector, FLOW_DISSECTOR_KEY_BASIC)) {
                struct flow_dissector_key_basic *key =
                        GET_KEY(tc_flow_cmd, FLOW_DISSECTOR_KEY_BASIC);
                struct flow_dissector_key_basic *mask =
                        GET_MASK(tc_flow_cmd, FLOW_DISSECTOR_KEY_BASIC);

                flow->l2_key.ether_type = key->n_proto;
                flow->l2_mask.ether_type = mask->n_proto;

                if (key->n_proto == htons(ETH_P_IP) ||
                    key->n_proto == htons(ETH_P_IPV6)) {
                        flow->l4_key.ip_proto = key->ip_proto;
                        flow->l4_mask.ip_proto = mask->ip_proto;
                }
        }

        if (dissector_uses_key(dissector, FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
                struct flow_dissector_key_eth_addrs *key =
                        GET_KEY(tc_flow_cmd, FLOW_DISSECTOR_KEY_ETH_ADDRS);
                struct flow_dissector_key_eth_addrs *mask =
                        GET_MASK(tc_flow_cmd, FLOW_DISSECTOR_KEY_ETH_ADDRS);

                flow->flags |= BNXT_TC_FLOW_FLAGS_ETH_ADDRS;
                ether_addr_copy(flow->l2_key.dmac, key->dst);
                ether_addr_copy(flow->l2_mask.dmac, mask->dst);
                ether_addr_copy(flow->l2_key.smac, key->src);
                ether_addr_copy(flow->l2_mask.smac, mask->src);
        }

        if (dissector_uses_key(dissector, FLOW_DISSECTOR_KEY_VLAN)) {
                struct flow_dissector_key_vlan *key =
                        GET_KEY(tc_flow_cmd, FLOW_DISSECTOR_KEY_VLAN);
                struct flow_dissector_key_vlan *mask =
                        GET_MASK(tc_flow_cmd, FLOW_DISSECTOR_KEY_VLAN);

                flow->l2_key.inner_vlan_tci =
                   cpu_to_be16(VLAN_TCI(key->vlan_id, key->vlan_priority));
                flow->l2_mask.inner_vlan_tci =
                   cpu_to_be16((VLAN_TCI(mask->vlan_id, mask->vlan_priority)));
                flow->l2_key.inner_vlan_tpid = htons(ETH_P_8021Q);
                flow->l2_mask.inner_vlan_tpid = htons(0xffff);
                flow->l2_key.num_vlans = 1;
        }

        if (dissector_uses_key(dissector, FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
                struct flow_dissector_key_ipv4_addrs *key =
                        GET_KEY(tc_flow_cmd, FLOW_DISSECTOR_KEY_IPV4_ADDRS);
                struct flow_dissector_key_ipv4_addrs *mask =
                        GET_MASK(tc_flow_cmd, FLOW_DISSECTOR_KEY_IPV4_ADDRS);

                flow->flags |= BNXT_TC_FLOW_FLAGS_IPV4_ADDRS;
                flow->l3_key.ipv4.daddr.s_addr = key->dst;
                flow->l3_mask.ipv4.daddr.s_addr = mask->dst;
                flow->l3_key.ipv4.saddr.s_addr = key->src;
                flow->l3_mask.ipv4.saddr.s_addr = mask->src;
        } else if (dissector_uses_key(dissector,
                                      FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
                struct flow_dissector_key_ipv6_addrs *key =
                        GET_KEY(tc_flow_cmd, FLOW_DISSECTOR_KEY_IPV6_ADDRS);
                struct flow_dissector_key_ipv6_addrs *mask =
                        GET_MASK(tc_flow_cmd, FLOW_DISSECTOR_KEY_IPV6_ADDRS);

                flow->flags |= BNXT_TC_FLOW_FLAGS_IPV6_ADDRS;
                flow->l3_key.ipv6.daddr = key->dst;
                flow->l3_mask.ipv6.daddr = mask->dst;
                flow->l3_key.ipv6.saddr = key->src;
                flow->l3_mask.ipv6.saddr = mask->src;
        }

        if (dissector_uses_key(dissector, FLOW_DISSECTOR_KEY_PORTS)) {
                struct flow_dissector_key_ports *key =
                        GET_KEY(tc_flow_cmd, FLOW_DISSECTOR_KEY_PORTS);
                struct flow_dissector_key_ports *mask =
                        GET_MASK(tc_flow_cmd, FLOW_DISSECTOR_KEY_PORTS);

                flow->flags |= BNXT_TC_FLOW_FLAGS_PORTS;
                flow->l4_key.ports.dport = key->dst;
                flow->l4_mask.ports.dport = mask->dst;
                flow->l4_key.ports.sport = key->src;
                flow->l4_mask.ports.sport = mask->src;
        }

        if (dissector_uses_key(dissector, FLOW_DISSECTOR_KEY_ICMP)) {
                struct flow_dissector_key_icmp *key =
                        GET_KEY(tc_flow_cmd, FLOW_DISSECTOR_KEY_ICMP);
                struct flow_dissector_key_icmp *mask =
                        GET_MASK(tc_flow_cmd, FLOW_DISSECTOR_KEY_ICMP);

                flow->flags |= BNXT_TC_FLOW_FLAGS_ICMP;
                flow->l4_key.icmp.type = key->type;
                flow->l4_key.icmp.code = key->code;
                flow->l4_mask.icmp.type = mask->type;
                flow->l4_mask.icmp.code = mask->code;
        }

        return bnxt_tc_parse_actions(bp, &flow->actions, tc_flow_cmd->exts);
}

static int bnxt_hwrm_cfa_flow_free(struct bnxt *bp, __le16 flow_handle)
{
        struct hwrm_cfa_flow_free_input req = { 0 };
        int rc;

        bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_CFA_FLOW_FREE, -1, -1);
        req.flow_handle = flow_handle;

        rc = hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
        if (rc)
                netdev_info(bp->dev, "Error: %s: flow_handle=0x%x rc=%d",
                            __func__, flow_handle, rc);
        return rc;
}

static int ipv6_mask_len(struct in6_addr *mask)
{
        int mask_len = 0, i;

        for (i = 0; i < 4; i++)
                mask_len += inet_mask_len(mask->s6_addr32[i]);

        return mask_len;
}

static bool is_wildcard(void *mask, int len)
{
        const u8 *p = mask;
        int i;

        for (i = 0; i < len; i++) {
                if (p[i] != 0)
                        return false;
        }
        return true;
}

static int bnxt_hwrm_cfa_flow_alloc(struct bnxt *bp, struct bnxt_tc_flow *flow,
                                    __le16 ref_flow_handle, __le16 *flow_handle)
{
        struct hwrm_cfa_flow_alloc_output *resp = bp->hwrm_cmd_resp_addr;
        struct bnxt_tc_actions *actions = &flow->actions;
        struct bnxt_tc_l3_key *l3_mask = &flow->l3_mask;
        struct bnxt_tc_l3_key *l3_key = &flow->l3_key;
        struct hwrm_cfa_flow_alloc_input req = { 0 };
        u16 flow_flags = 0, action_flags = 0;
        int rc;

        bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_CFA_FLOW_ALLOC, -1, -1);

        req.src_fid = cpu_to_le16(flow->src_fid);
        req.ref_flow_handle = ref_flow_handle;
        req.ethertype = flow->l2_key.ether_type;
        req.ip_proto = flow->l4_key.ip_proto;

        if (flow->flags & BNXT_TC_FLOW_FLAGS_ETH_ADDRS) {
                memcpy(req.dmac, flow->l2_key.dmac, ETH_ALEN);
                memcpy(req.smac, flow->l2_key.smac, ETH_ALEN);
        }

        if (flow->l2_key.num_vlans > 0) {
                flow_flags |= CFA_FLOW_ALLOC_REQ_FLAGS_NUM_VLAN_ONE;
                /* FW expects the inner_vlan_tci value to be set
                 * in outer_vlan_tci when num_vlans is 1 (which is
                 * always the case in TC.)
                 */
                req.outer_vlan_tci = flow->l2_key.inner_vlan_tci;
        }

        /* If all IP and L4 fields are wildcarded then this is an L2 flow */
        if (is_wildcard(&l3_mask, sizeof(l3_mask)) &&
            is_wildcard(&flow->l4_mask, sizeof(flow->l4_mask))) {
                flow_flags |= CFA_FLOW_ALLOC_REQ_FLAGS_FLOWTYPE_L2;
        } else {
                flow_flags |= flow->l2_key.ether_type == htons(ETH_P_IP) ?
                                CFA_FLOW_ALLOC_REQ_FLAGS_FLOWTYPE_IPV4 :
                                CFA_FLOW_ALLOC_REQ_FLAGS_FLOWTYPE_IPV6;

                if (flow->flags & BNXT_TC_FLOW_FLAGS_IPV4_ADDRS) {
                        req.ip_dst[0] = l3_key->ipv4.daddr.s_addr;
                        req.ip_dst_mask_len =
                                inet_mask_len(l3_mask->ipv4.daddr.s_addr);
                        req.ip_src[0] = l3_key->ipv4.saddr.s_addr;
                        req.ip_src_mask_len =
                                inet_mask_len(l3_mask->ipv4.saddr.s_addr);
                } else if (flow->flags & BNXT_TC_FLOW_FLAGS_IPV6_ADDRS) {
                        memcpy(req.ip_dst, l3_key->ipv6.daddr.s6_addr32,
                               sizeof(req.ip_dst));
                        req.ip_dst_mask_len =
                                        ipv6_mask_len(&l3_mask->ipv6.daddr);
                        memcpy(req.ip_src, l3_key->ipv6.saddr.s6_addr32,
                               sizeof(req.ip_src));
                        req.ip_src_mask_len =
                                        ipv6_mask_len(&l3_mask->ipv6.saddr);
                }
        }

        if (flow->flags & BNXT_TC_FLOW_FLAGS_PORTS) {
                req.l4_src_port = flow->l4_key.ports.sport;
                req.l4_src_port_mask = flow->l4_mask.ports.sport;
                req.l4_dst_port = flow->l4_key.ports.dport;
                req.l4_dst_port_mask = flow->l4_mask.ports.dport;
        } else if (flow->flags & BNXT_TC_FLOW_FLAGS_ICMP) {
                /* l4 ports serve as type/code when ip_proto is ICMP */
                req.l4_src_port = htons(flow->l4_key.icmp.type);
                req.l4_src_port_mask = htons(flow->l4_mask.icmp.type);
                req.l4_dst_port = htons(flow->l4_key.icmp.code);
                req.l4_dst_port_mask = htons(flow->l4_mask.icmp.code);
        }
        req.flags = cpu_to_le16(flow_flags);

        if (actions->flags & BNXT_TC_ACTION_FLAG_DROP) {
                action_flags |= CFA_FLOW_ALLOC_REQ_ACTION_FLAGS_DROP;
        } else {
                if (actions->flags & BNXT_TC_ACTION_FLAG_FWD) {
                        action_flags |= CFA_FLOW_ALLOC_REQ_ACTION_FLAGS_FWD;
                        req.dst_fid = cpu_to_le16(actions->dst_fid);
                }
                if (actions->flags & BNXT_TC_ACTION_FLAG_PUSH_VLAN) {
                        action_flags |=
                            CFA_FLOW_ALLOC_REQ_ACTION_FLAGS_L2_HEADER_REWRITE;
                        req.l2_rewrite_vlan_tpid = actions->push_vlan_tpid;
                        req.l2_rewrite_vlan_tci = actions->push_vlan_tci;
                        memcpy(&req.l2_rewrite_dmac, &req.dmac, ETH_ALEN);
                        memcpy(&req.l2_rewrite_smac, &req.smac, ETH_ALEN);
                }
                if (actions->flags & BNXT_TC_ACTION_FLAG_POP_VLAN) {
                        action_flags |=
                            CFA_FLOW_ALLOC_REQ_ACTION_FLAGS_L2_HEADER_REWRITE;
                        /* Rewrite config with tpid = 0 implies vlan pop */
                        req.l2_rewrite_vlan_tpid = 0;
                        memcpy(&req.l2_rewrite_dmac, &req.dmac, ETH_ALEN);
                        memcpy(&req.l2_rewrite_smac, &req.smac, ETH_ALEN);
                }
        }
        req.action_flags = cpu_to_le16(action_flags);

        mutex_lock(&bp->hwrm_cmd_lock);

        rc = _hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
        if (!rc)
                *flow_handle = resp->flow_handle;

        mutex_unlock(&bp->hwrm_cmd_lock);

        return rc;
}

/* Add val to accum while handling a possible wraparound
 * of val. Eventhough val is of type u64, its actual width
 * is denoted by mask and will wrap-around beyond that width.
 */
static void accumulate_val(u64 *accum, u64 val, u64 mask)
{
#define low_bits(x, mask)               ((x) & (mask))
#define high_bits(x, mask)              ((x) & ~(mask))
        bool wrapped = val < low_bits(*accum, mask);

        *accum = high_bits(*accum, mask) + val;
        if (wrapped)
                *accum += (mask + 1);
}

/* The HW counters' width is much less than 64bits.
 * Handle possible wrap-around while updating the stat counters
 */
static void bnxt_flow_stats_fix_wraparound(struct bnxt_tc_info *tc_info,
                                           struct bnxt_tc_flow_stats *stats,
                                           struct bnxt_tc_flow_stats *hw_stats)
{
        accumulate_val(&stats->bytes, hw_stats->bytes, tc_info->bytes_mask);
        accumulate_val(&stats->packets, hw_stats->packets,
                       tc_info->packets_mask);
}

/* Fix possible wraparound of the stats queried from HW, calculate
 * the delta from prev_stats, and also update the prev_stats.
 * The HW flow stats are fetched under the hwrm_cmd_lock mutex.
 * This routine is best called while under the mutex so that the
 * stats processing happens atomically.
 */
static void bnxt_flow_stats_calc(struct bnxt_tc_info *tc_info,
                                 struct bnxt_tc_flow *flow,
                                 struct bnxt_tc_flow_stats *stats)
{
        struct bnxt_tc_flow_stats *acc_stats, *prev_stats;

        acc_stats = &flow->stats;
        bnxt_flow_stats_fix_wraparound(tc_info, acc_stats, stats);

        prev_stats = &flow->prev_stats;
        stats->bytes = acc_stats->bytes - prev_stats->bytes;
        stats->packets = acc_stats->packets - prev_stats->packets;
        *prev_stats = *acc_stats;
}

static int bnxt_hwrm_cfa_flow_stats_get(struct bnxt *bp,
                                        __le16 flow_handle,
                                        struct bnxt_tc_flow *flow,
                                        struct bnxt_tc_flow_stats *stats)
{
        struct hwrm_cfa_flow_stats_output *resp = bp->hwrm_cmd_resp_addr;
        struct hwrm_cfa_flow_stats_input req = { 0 };
        int rc;

        bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_CFA_FLOW_STATS, -1, -1);
        req.num_flows = cpu_to_le16(1);
        req.flow_handle_0 = flow_handle;

        mutex_lock(&bp->hwrm_cmd_lock);
        rc = _hwrm_send_message(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
        if (!rc) {
                stats->packets = le64_to_cpu(resp->packet_0);
                stats->bytes = le64_to_cpu(resp->byte_0);
                bnxt_flow_stats_calc(&bp->tc_info, flow, stats);
        } else {
                netdev_info(bp->dev, "error rc=%d", rc);
        }

        mutex_unlock(&bp->hwrm_cmd_lock);
        return rc;
}

static int bnxt_tc_put_l2_node(struct bnxt *bp,
                               struct bnxt_tc_flow_node *flow_node)
{
        struct bnxt_tc_l2_node *l2_node = flow_node->l2_node;
        struct bnxt_tc_info *tc_info = &bp->tc_info;
        int rc;

        /* remove flow_node from the L2 shared flow list */
        list_del(&flow_node->l2_list_node);
        if (--l2_node->refcount == 0) {
                rc =  rhashtable_remove_fast(&tc_info->l2_table, &l2_node->node,
                                             tc_info->l2_ht_params);
                if (rc)
                        netdev_err(bp->dev,
                                   "Error: %s: rhashtable_remove_fast: %d",
                                   __func__, rc);
                kfree_rcu(l2_node, rcu);
        }
        return 0;
}

static struct bnxt_tc_l2_node *
bnxt_tc_get_l2_node(struct bnxt *bp, struct rhashtable *l2_table,
                    struct rhashtable_params ht_params,
                    struct bnxt_tc_l2_key *l2_key)
{
        struct bnxt_tc_l2_node *l2_node;
        int rc;

        l2_node = rhashtable_lookup_fast(l2_table, l2_key, ht_params);
        if (!l2_node) {
                l2_node = kzalloc(sizeof(*l2_node), GFP_KERNEL);
                if (!l2_node) {
                        rc = -ENOMEM;
                        return NULL;
                }

                l2_node->key = *l2_key;
                rc = rhashtable_insert_fast(l2_table, &l2_node->node,
                                            ht_params);
                if (rc) {
                        kfree(l2_node);
                        netdev_err(bp->dev,
                                   "Error: %s: rhashtable_insert_fast: %d",
                                   __func__, rc);
                        return NULL;
                }
                INIT_LIST_HEAD(&l2_node->common_l2_flows);
        }
        return l2_node;
}

/* Get the ref_flow_handle for a flow by checking if there are any other
 * flows that share the same L2 key as this flow.
 */
static int
bnxt_tc_get_ref_flow_handle(struct bnxt *bp, struct bnxt_tc_flow *flow,
                            struct bnxt_tc_flow_node *flow_node,
                            __le16 *ref_flow_handle)
{
        struct bnxt_tc_info *tc_info = &bp->tc_info;
        struct bnxt_tc_flow_node *ref_flow_node;
        struct bnxt_tc_l2_node *l2_node;

        l2_node = bnxt_tc_get_l2_node(bp, &tc_info->l2_table,
                                      tc_info->l2_ht_params,
                                      &flow->l2_key);
        if (!l2_node)
                return -1;

        /* If any other flow is using this l2_node, use it's flow_handle
         * as the ref_flow_handle
         */
        if (l2_node->refcount > 0) {
                ref_flow_node = list_first_entry(&l2_node->common_l2_flows,
                                                 struct bnxt_tc_flow_node,
                                                 l2_list_node);
                *ref_flow_handle = ref_flow_node->flow_handle;
        } else {
                *ref_flow_handle = cpu_to_le16(0xffff);
        }

        /* Insert the l2_node into the flow_node so that subsequent flows
         * with a matching l2 key can use the flow_handle of this flow
         * as their ref_flow_handle
         */
        flow_node->l2_node = l2_node;
        list_add(&flow_node->l2_list_node, &l2_node->common_l2_flows);
        l2_node->refcount++;
        return 0;
}

/* After the flow parsing is done, this routine is used for checking
 * if there are any aspects of the flow that prevent it from being
 * offloaded.
 */
static bool bnxt_tc_can_offload(struct bnxt *bp, struct bnxt_tc_flow *flow)
{
        /* If L4 ports are specified then ip_proto must be TCP or UDP */
        if ((flow->flags & BNXT_TC_FLOW_FLAGS_PORTS) &&
            (flow->l4_key.ip_proto != IPPROTO_TCP &&
             flow->l4_key.ip_proto != IPPROTO_UDP)) {
                netdev_info(bp->dev, "Cannot offload non-TCP/UDP (%d) ports",
                            flow->l4_key.ip_proto);
                return false;
        }

        return true;
}

static int __bnxt_tc_del_flow(struct bnxt *bp,
                              struct bnxt_tc_flow_node *flow_node)
{
        struct bnxt_tc_info *tc_info = &bp->tc_info;
        int rc;

        /* send HWRM cmd to free the flow-id */
        bnxt_hwrm_cfa_flow_free(bp, flow_node->flow_handle);

        mutex_lock(&tc_info->lock);

        /* release reference to l2 node */
        bnxt_tc_put_l2_node(bp, flow_node);

        mutex_unlock(&tc_info->lock);

        rc = rhashtable_remove_fast(&tc_info->flow_table, &flow_node->node,
                                    tc_info->flow_ht_params);
        if (rc)
                netdev_err(bp->dev, "Error: %s: rhashtable_remove_fast rc=%d",
                           __func__, rc);

        kfree_rcu(flow_node, rcu);
        return 0;
}

/* Add a new flow or replace an existing flow.
 * Notes on locking:
 * There are essentially two critical sections here.
 * 1. while adding a new flow
 *    a) lookup l2-key
 *    b) issue HWRM cmd and get flow_handle
 *    c) link l2-key with flow
 * 2. while deleting a flow
 *    a) unlinking l2-key from flow
 * A lock is needed to protect these two critical sections.
 *
 * The hash-tables are already protected by the rhashtable API.
 */
static int bnxt_tc_add_flow(struct bnxt *bp, u16 src_fid,
                            struct tc_cls_flower_offload *tc_flow_cmd)
{
        struct bnxt_tc_flow_node *new_node, *old_node;
        struct bnxt_tc_info *tc_info = &bp->tc_info;
        struct bnxt_tc_flow *flow;
        __le16 ref_flow_handle;
        int rc;

        /* allocate memory for the new flow and it's node */
        new_node = kzalloc(sizeof(*new_node), GFP_KERNEL);
        if (!new_node) {
                rc = -ENOMEM;
                goto done;
        }
        new_node->cookie = tc_flow_cmd->cookie;
        flow = &new_node->flow;

        rc = bnxt_tc_parse_flow(bp, tc_flow_cmd, flow);
        if (rc)
                goto free_node;
        flow->src_fid = src_fid;

        if (!bnxt_tc_can_offload(bp, flow)) {
                rc = -ENOSPC;
                goto free_node;
        }

        /* If a flow exists with the same cookie, delete it */
        old_node = rhashtable_lookup_fast(&tc_info->flow_table,
                                          &tc_flow_cmd->cookie,
                                          tc_info->flow_ht_params);
        if (old_node)
                __bnxt_tc_del_flow(bp, old_node);

        /* Check if the L2 part of the flow has been offloaded already.
         * If so, bump up it's refcnt and get it's reference handle.
         */
        mutex_lock(&tc_info->lock);
        rc = bnxt_tc_get_ref_flow_handle(bp, flow, new_node, &ref_flow_handle);
        if (rc)
                goto unlock;

        /* send HWRM cmd to alloc the flow */
        rc = bnxt_hwrm_cfa_flow_alloc(bp, flow, ref_flow_handle,
                                      &new_node->flow_handle);
        if (rc)
                goto put_l2;

        /* add new flow to flow-table */
        rc = rhashtable_insert_fast(&tc_info->flow_table, &new_node->node,
                                    tc_info->flow_ht_params);
        if (rc)
                goto hwrm_flow_free;

        mutex_unlock(&tc_info->lock);
        return 0;

hwrm_flow_free:
        bnxt_hwrm_cfa_flow_free(bp, new_node->flow_handle);
put_l2:
        bnxt_tc_put_l2_node(bp, new_node);
unlock:
        mutex_unlock(&tc_info->lock);
free_node:
        kfree(new_node);
done:
        netdev_err(bp->dev, "Error: %s: cookie=0x%lx error=%d",
                   __func__, tc_flow_cmd->cookie, rc);
        return rc;
}

static int bnxt_tc_del_flow(struct bnxt *bp,
                            struct tc_cls_flower_offload *tc_flow_cmd)
{
        struct bnxt_tc_info *tc_info = &bp->tc_info;
        struct bnxt_tc_flow_node *flow_node;

        flow_node = rhashtable_lookup_fast(&tc_info->flow_table,
                                           &tc_flow_cmd->cookie,
                                           tc_info->flow_ht_params);
        if (!flow_node) {
                netdev_info(bp->dev, "ERROR: no flow_node for cookie %lx",
                            tc_flow_cmd->cookie);
                return -EINVAL;
        }

        return __bnxt_tc_del_flow(bp, flow_node);
}

static int bnxt_tc_get_flow_stats(struct bnxt *bp,
                                  struct tc_cls_flower_offload *tc_flow_cmd)
{
        struct bnxt_tc_info *tc_info = &bp->tc_info;
        struct bnxt_tc_flow_node *flow_node;
        struct bnxt_tc_flow_stats stats;
        int rc;

        flow_node = rhashtable_lookup_fast(&tc_info->flow_table,
                                           &tc_flow_cmd->cookie,
                                           tc_info->flow_ht_params);
        if (!flow_node) {
                netdev_info(bp->dev, "Error: no flow_node for cookie %lx",
                            tc_flow_cmd->cookie);
                return -1;
        }

        rc = bnxt_hwrm_cfa_flow_stats_get(bp, flow_node->flow_handle,
                                          &flow_node->flow, &stats);
        if (rc)
                return rc;

        tcf_exts_stats_update(tc_flow_cmd->exts, stats.bytes, stats.packets, 0);
        return 0;
}

int bnxt_tc_setup_flower(struct bnxt *bp, u16 src_fid,
                         struct tc_cls_flower_offload *cls_flower)
{
        int rc = 0;

        if (!is_classid_clsact_ingress(cls_flower->common.classid) ||
            cls_flower->common.chain_index)
                return -EOPNOTSUPP;

        switch (cls_flower->command) {
        case TC_CLSFLOWER_REPLACE:
                rc = bnxt_tc_add_flow(bp, src_fid, cls_flower);
                break;

        case TC_CLSFLOWER_DESTROY:
                rc = bnxt_tc_del_flow(bp, cls_flower);
                break;

        case TC_CLSFLOWER_STATS:
                rc = bnxt_tc_get_flow_stats(bp, cls_flower);
                break;
        }
        return rc;
}

static const struct rhashtable_params bnxt_tc_flow_ht_params = {
        .head_offset = offsetof(struct bnxt_tc_flow_node, node),
        .key_offset = offsetof(struct bnxt_tc_flow_node, cookie),
        .key_len = sizeof(((struct bnxt_tc_flow_node *)0)->cookie),
        .automatic_shrinking = true
};

static const struct rhashtable_params bnxt_tc_l2_ht_params = {
        .head_offset = offsetof(struct bnxt_tc_l2_node, node),
        .key_offset = offsetof(struct bnxt_tc_l2_node, key),
        .key_len = BNXT_TC_L2_KEY_LEN,
        .automatic_shrinking = true
};

/* convert counter width in bits to a mask */
#define mask(width)             ((u64)~0 >> (64 - (width)))

int bnxt_init_tc(struct bnxt *bp)
{
        struct bnxt_tc_info *tc_info = &bp->tc_info;
        int rc;

        if (bp->hwrm_spec_code < 0x10800) {
                netdev_warn(bp->dev,
                            "Firmware does not support TC flower offload.\n");
                return -ENOTSUPP;
        }
        mutex_init(&tc_info->lock);

        /* Counter widths are programmed by FW */
        tc_info->bytes_mask = mask(36);
        tc_info->packets_mask = mask(28);

        tc_info->flow_ht_params = bnxt_tc_flow_ht_params;
        rc = rhashtable_init(&tc_info->flow_table, &tc_info->flow_ht_params);
        if (rc)
                return rc;

        tc_info->l2_ht_params = bnxt_tc_l2_ht_params;
        rc = rhashtable_init(&tc_info->l2_table, &tc_info->l2_ht_params);
        if (rc)
                goto destroy_flow_table;

        tc_info->enabled = true;
        bp->dev->hw_features |= NETIF_F_HW_TC;
        bp->dev->features |= NETIF_F_HW_TC;
        return 0;

destroy_flow_table:
        rhashtable_destroy(&tc_info->flow_table);
        return rc;
}

void bnxt_shutdown_tc(struct bnxt *bp)
{
        struct bnxt_tc_info *tc_info = &bp->tc_info;

        if (!tc_info->enabled)
                return;

        rhashtable_destroy(&tc_info->flow_table);
        rhashtable_destroy(&tc_info->l2_table);
}

#else
#endif