// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/*
 * Copyright(c) 2017 - 2020 Intel Corporation.
 */

/*
 * This file contains HFI1 support for VNIC functionality
 */

#include <linux/io.h>
#include <linux/if_vlan.h>

#include "vnic.h"
#include "netdev.h"

#define HFI_TX_TIMEOUT_MS 1000

#define HFI1_VNIC_RCV_Q_SIZE   1024

#define HFI1_VNIC_UP 0

static DEFINE_SPINLOCK(vport_cntr_lock);

#define SUM_GRP_COUNTERS(stats, qstats, x_grp) do {            \
                u64 *src64, *dst64;                            \
                for (src64 = &qstats->x_grp.unicast,           \
                        dst64 = &stats->x_grp.unicast;         \
                        dst64 <= &stats->x_grp.s_1519_max;) {  \
                        *dst64++ += *src64++;                  \
                }                                              \
        } while (0)

#define VNIC_MASK (0xFF)
#define VNIC_ID(val) ((1ull << 24) | ((val) & VNIC_MASK))

/* hfi1_vnic_update_stats - update statistics */
static void hfi1_vnic_update_stats(struct hfi1_vnic_vport_info *vinfo,
                                   struct opa_vnic_stats *stats)
{
        struct net_device *netdev = vinfo->netdev;
        u8 i;

        /* add tx counters on different queues */
        for (i = 0; i < vinfo->num_tx_q; i++) {
                struct opa_vnic_stats *qstats = &vinfo->stats[i];
                struct rtnl_link_stats64 *qnstats = &vinfo->stats[i].netstats;

                stats->netstats.tx_fifo_errors += qnstats->tx_fifo_errors;
                stats->netstats.tx_carrier_errors += qnstats->tx_carrier_errors;
                stats->tx_drop_state += qstats->tx_drop_state;
                stats->tx_dlid_zero += qstats->tx_dlid_zero;

                SUM_GRP_COUNTERS(stats, qstats, tx_grp);
                stats->netstats.tx_packets += qnstats->tx_packets;
                stats->netstats.tx_bytes += qnstats->tx_bytes;
        }

        /* add rx counters on different queues */
        for (i = 0; i < vinfo->num_rx_q; i++) {
                struct opa_vnic_stats *qstats = &vinfo->stats[i];
                struct rtnl_link_stats64 *qnstats = &vinfo->stats[i].netstats;

                stats->netstats.rx_fifo_errors += qnstats->rx_fifo_errors;
                stats->netstats.rx_nohandler += qnstats->rx_nohandler;
                stats->rx_drop_state += qstats->rx_drop_state;
                stats->rx_oversize += qstats->rx_oversize;
                stats->rx_runt += qstats->rx_runt;

                SUM_GRP_COUNTERS(stats, qstats, rx_grp);
                stats->netstats.rx_packets += qnstats->rx_packets;
                stats->netstats.rx_bytes += qnstats->rx_bytes;
        }

        stats->netstats.tx_errors = stats->netstats.tx_fifo_errors +
                                    stats->netstats.tx_carrier_errors +
                                    stats->tx_drop_state + stats->tx_dlid_zero;
        stats->netstats.tx_dropped = stats->netstats.tx_errors;

        stats->netstats.rx_errors = stats->netstats.rx_fifo_errors +
                                    stats->netstats.rx_nohandler +
                                    stats->rx_drop_state + stats->rx_oversize +
                                    stats->rx_runt;
        stats->netstats.rx_dropped = stats->netstats.rx_errors;

        netdev->stats.tx_packets = stats->netstats.tx_packets;
        netdev->stats.tx_bytes = stats->netstats.tx_bytes;
        netdev->stats.tx_fifo_errors = stats->netstats.tx_fifo_errors;
        netdev->stats.tx_carrier_errors = stats->netstats.tx_carrier_errors;
        netdev->stats.tx_errors = stats->netstats.tx_errors;
        netdev->stats.tx_dropped = stats->netstats.tx_dropped;

        netdev->stats.rx_packets = stats->netstats.rx_packets;
        netdev->stats.rx_bytes = stats->netstats.rx_bytes;
        netdev->stats.rx_fifo_errors = stats->netstats.rx_fifo_errors;
        netdev->stats.multicast = stats->rx_grp.mcastbcast;
        netdev->stats.rx_length_errors = stats->rx_oversize + stats->rx_runt;
        netdev->stats.rx_errors = stats->netstats.rx_errors;
        netdev->stats.rx_dropped = stats->netstats.rx_dropped;
}

/* update_len_counters - update pkt's len histogram counters */
static inline void update_len_counters(struct opa_vnic_grp_stats *grp,
                                       int len)
{
        /* account for 4 byte FCS */
        if (len >= 1515)
                grp->s_1519_max++;
        else if (len >= 1020)
                grp->s_1024_1518++;
        else if (len >= 508)
                grp->s_512_1023++;
        else if (len >= 252)
                grp->s_256_511++;
        else if (len >= 124)
                grp->s_128_255++;
        else if (len >= 61)
                grp->s_65_127++;
        else
                grp->s_64++;
}

/* hfi1_vnic_update_tx_counters - update transmit counters */
static void hfi1_vnic_update_tx_counters(struct hfi1_vnic_vport_info *vinfo,
                                         u8 q_idx, struct sk_buff *skb, int err)
{
        struct ethhdr *mac_hdr = (struct ethhdr *)skb_mac_header(skb);
        struct opa_vnic_stats *stats = &vinfo->stats[q_idx];
        struct opa_vnic_grp_stats *tx_grp = &stats->tx_grp;
        u16 vlan_tci;

        stats->netstats.tx_packets++;
        stats->netstats.tx_bytes += skb->len + ETH_FCS_LEN;

        update_len_counters(tx_grp, skb->len);

        /* rest of the counts are for good packets only */
        if (unlikely(err))
                return;

        if (is_multicast_ether_addr(mac_hdr->h_dest))
                tx_grp->mcastbcast++;
        else
                tx_grp->unicast++;

        if (!__vlan_get_tag(skb, &vlan_tci))
                tx_grp->vlan++;
        else
                tx_grp->untagged++;
}

/* hfi1_vnic_update_rx_counters - update receive counters */
static void hfi1_vnic_update_rx_counters(struct hfi1_vnic_vport_info *vinfo,
                                         u8 q_idx, struct sk_buff *skb, int err)
{
        struct ethhdr *mac_hdr = (struct ethhdr *)skb->data;
        struct opa_vnic_stats *stats = &vinfo->stats[q_idx];
        struct opa_vnic_grp_stats *rx_grp = &stats->rx_grp;
        u16 vlan_tci;

        stats->netstats.rx_packets++;
        stats->netstats.rx_bytes += skb->len + ETH_FCS_LEN;

        update_len_counters(rx_grp, skb->len);

        /* rest of the counts are for good packets only */
        if (unlikely(err))
                return;

        if (is_multicast_ether_addr(mac_hdr->h_dest))
                rx_grp->mcastbcast++;
        else
                rx_grp->unicast++;

        if (!__vlan_get_tag(skb, &vlan_tci))
                rx_grp->vlan++;
        else
                rx_grp->untagged++;
}

/* This function is overloaded for opa_vnic specific implementation */
static void hfi1_vnic_get_stats64(struct net_device *netdev,
                                  struct rtnl_link_stats64 *stats)
{
        struct opa_vnic_stats *vstats = (struct opa_vnic_stats *)stats;
        struct hfi1_vnic_vport_info *vinfo = opa_vnic_dev_priv(netdev);

        hfi1_vnic_update_stats(vinfo, vstats);
}

static u64 create_bypass_pbc(u32 vl, u32 dw_len)
{
        u64 pbc;

        pbc = ((u64)PBC_IHCRC_NONE << PBC_INSERT_HCRC_SHIFT)
                | PBC_INSERT_BYPASS_ICRC | PBC_CREDIT_RETURN
                | PBC_PACKET_BYPASS
                | ((vl & PBC_VL_MASK) << PBC_VL_SHIFT)
                | (dw_len & PBC_LENGTH_DWS_MASK) << PBC_LENGTH_DWS_SHIFT;

        return pbc;
}

/* hfi1_vnic_maybe_stop_tx - stop tx queue if required */
static void hfi1_vnic_maybe_stop_tx(struct hfi1_vnic_vport_info *vinfo,
                                    u8 q_idx)
{
        netif_stop_subqueue(vinfo->netdev, q_idx);
        if (!hfi1_vnic_sdma_write_avail(vinfo, q_idx))
                return;

        netif_start_subqueue(vinfo->netdev, q_idx);
}

static netdev_tx_t hfi1_netdev_start_xmit(struct sk_buff *skb,
                                          struct net_device *netdev)
{
        struct hfi1_vnic_vport_info *vinfo = opa_vnic_dev_priv(netdev);
        u8 pad_len, q_idx = skb->queue_mapping;
        struct hfi1_devdata *dd = vinfo->dd;
        struct opa_vnic_skb_mdata *mdata;
        u32 pkt_len, total_len;
        int err = -EINVAL;
        u64 pbc;

        v_dbg("xmit: queue %d skb len %d\n", q_idx, skb->len);
        if (unlikely(!netif_oper_up(netdev))) {
                vinfo->stats[q_idx].tx_drop_state++;
                goto tx_finish;
        }

        /* take out meta data */
        mdata = (struct opa_vnic_skb_mdata *)skb->data;
        skb_pull(skb, sizeof(*mdata));
        if (unlikely(mdata->flags & OPA_VNIC_SKB_MDATA_ENCAP_ERR)) {
                vinfo->stats[q_idx].tx_dlid_zero++;
                goto tx_finish;
        }

        /* add tail padding (for 8 bytes size alignment) and icrc */
        pad_len = -(skb->len + OPA_VNIC_ICRC_TAIL_LEN) & 0x7;
        pad_len += OPA_VNIC_ICRC_TAIL_LEN;

        /*
         * pkt_len is how much data we have to write, includes header and data.
         * total_len is length of the packet in Dwords plus the PBC should not
         * include the CRC.
         */
        pkt_len = (skb->len + pad_len) >> 2;
        total_len = pkt_len + 2; /* PBC + packet */

        pbc = create_bypass_pbc(mdata->vl, total_len);

        skb_get(skb);
        v_dbg("pbc 0x%016llX len %d pad_len %d\n", pbc, skb->len, pad_len);
        err = dd->process_vnic_dma_send(dd, q_idx, vinfo, skb, pbc, pad_len);
        if (unlikely(err)) {
                if (err == -ENOMEM)
                        vinfo->stats[q_idx].netstats.tx_fifo_errors++;
                else if (err != -EBUSY)
                        vinfo->stats[q_idx].netstats.tx_carrier_errors++;
        }
        /* remove the header before updating tx counters */
        skb_pull(skb, OPA_VNIC_HDR_LEN);

        if (unlikely(err == -EBUSY)) {
                hfi1_vnic_maybe_stop_tx(vinfo, q_idx);
                dev_kfree_skb_any(skb);
                return NETDEV_TX_BUSY;
        }

tx_finish:
        /* update tx counters */
        hfi1_vnic_update_tx_counters(vinfo, q_idx, skb, err);
        dev_kfree_skb_any(skb);
        return NETDEV_TX_OK;
}

static u16 hfi1_vnic_select_queue(struct net_device *netdev,
                                  struct sk_buff *skb,
                                  struct net_device *sb_dev)
{
        struct hfi1_vnic_vport_info *vinfo = opa_vnic_dev_priv(netdev);
        struct opa_vnic_skb_mdata *mdata;
        struct sdma_engine *sde;

        mdata = (struct opa_vnic_skb_mdata *)skb->data;
        sde = sdma_select_engine_vl(vinfo->dd, mdata->entropy, mdata->vl);
        return sde->this_idx;
}

/* hfi1_vnic_decap_skb - strip OPA header from the skb (ethernet) packet */
static inline int hfi1_vnic_decap_skb(struct hfi1_vnic_rx_queue *rxq,
                                      struct sk_buff *skb)
{
        struct hfi1_vnic_vport_info *vinfo = rxq->vinfo;
        int max_len = vinfo->netdev->mtu + VLAN_ETH_HLEN;
        int rc = -EFAULT;

        skb_pull(skb, OPA_VNIC_HDR_LEN);

        /* Validate Packet length */
        if (unlikely(skb->len > max_len))
                vinfo->stats[rxq->idx].rx_oversize++;
        else if (unlikely(skb->len < ETH_ZLEN))
                vinfo->stats[rxq->idx].rx_runt++;
        else
                rc = 0;
        return rc;
}

static struct hfi1_vnic_vport_info *get_vnic_port(struct hfi1_devdata *dd,
                                                  int vesw_id)
{
        int vnic_id = VNIC_ID(vesw_id);

        return hfi1_netdev_get_data(dd, vnic_id);
}

static struct hfi1_vnic_vport_info *get_first_vnic_port(struct hfi1_devdata *dd)
{
        struct hfi1_vnic_vport_info *vinfo;
        int next_id = VNIC_ID(0);

        vinfo = hfi1_netdev_get_first_data(dd, &next_id);

        if (next_id > VNIC_ID(VNIC_MASK))
                return NULL;

        return vinfo;
}

void hfi1_vnic_bypass_rcv(struct hfi1_packet *packet)
{
        struct hfi1_devdata *dd = packet->rcd->dd;
        struct hfi1_vnic_vport_info *vinfo = NULL;
        struct hfi1_vnic_rx_queue *rxq;
        struct sk_buff *skb;
        int l4_type, vesw_id = -1, rc;
        u8 q_idx;
        unsigned char *pad_info;

        l4_type = hfi1_16B_get_l4(packet->ebuf);
        if (likely(l4_type == OPA_16B_L4_ETHR)) {
                vesw_id = HFI1_VNIC_GET_VESWID(packet->ebuf);
                vinfo = get_vnic_port(dd, vesw_id);

                /*
                 * In case of invalid vesw id, count the error on
                 * the first available vport.
                 */
                if (unlikely(!vinfo)) {
                        struct hfi1_vnic_vport_info *vinfo_tmp;

                        vinfo_tmp = get_first_vnic_port(dd);
                        if (vinfo_tmp) {
                                spin_lock(&vport_cntr_lock);
                                vinfo_tmp->stats[0].netstats.rx_nohandler++;
                                spin_unlock(&vport_cntr_lock);
                        }
                }
        }

        if (unlikely(!vinfo)) {
                dd_dev_warn(dd, "vnic rcv err: l4 %d vesw id %d ctx %d\n",
                            l4_type, vesw_id, packet->rcd->ctxt);
                return;
        }

        q_idx = packet->rcd->vnic_q_idx;
        rxq = &vinfo->rxq[q_idx];
        if (unlikely(!netif_oper_up(vinfo->netdev))) {
                vinfo->stats[q_idx].rx_drop_state++;
                return;
        }

        skb = netdev_alloc_skb(vinfo->netdev, packet->tlen);
        if (unlikely(!skb)) {
                vinfo->stats[q_idx].netstats.rx_fifo_errors++;
                return;
        }

        memcpy(skb->data, packet->ebuf, packet->tlen);
        skb_put(skb, packet->tlen);

        pad_info = skb->data + skb->len - 1;
        skb_trim(skb, (skb->len - OPA_VNIC_ICRC_TAIL_LEN -
                       ((*pad_info) & 0x7)));

        rc = hfi1_vnic_decap_skb(rxq, skb);

        /* update rx counters */
        hfi1_vnic_update_rx_counters(vinfo, rxq->idx, skb, rc);
        if (unlikely(rc)) {
                dev_kfree_skb_any(skb);
                return;
        }

        skb_checksum_none_assert(skb);
        skb->protocol = eth_type_trans(skb, rxq->netdev);

        napi_gro_receive(&rxq->napi, skb);
}

static int hfi1_vnic_up(struct hfi1_vnic_vport_info *vinfo)
{
        struct hfi1_devdata *dd = vinfo->dd;
        struct net_device *netdev = vinfo->netdev;
        int rc;

        /* ensure virtual eth switch id is valid */
        if (!vinfo->vesw_id)
                return -EINVAL;

        rc = hfi1_netdev_add_data(dd, VNIC_ID(vinfo->vesw_id), vinfo);
        if (rc < 0)
                return rc;

        rc = hfi1_netdev_rx_init(dd);
        if (rc)
                goto err_remove;

        netif_carrier_on(netdev);
        netif_tx_start_all_queues(netdev);
        set_bit(HFI1_VNIC_UP, &vinfo->flags);

        return 0;

err_remove:
        hfi1_netdev_remove_data(dd, VNIC_ID(vinfo->vesw_id));
        return rc;
}

static void hfi1_vnic_down(struct hfi1_vnic_vport_info *vinfo)
{
        struct hfi1_devdata *dd = vinfo->dd;

        clear_bit(HFI1_VNIC_UP, &vinfo->flags);
        netif_carrier_off(vinfo->netdev);
        netif_tx_disable(vinfo->netdev);
        hfi1_netdev_remove_data(dd, VNIC_ID(vinfo->vesw_id));

        hfi1_netdev_rx_destroy(dd);
}

static int hfi1_netdev_open(struct net_device *netdev)
{
        struct hfi1_vnic_vport_info *vinfo = opa_vnic_dev_priv(netdev);
        int rc;

        mutex_lock(&vinfo->lock);
        rc = hfi1_vnic_up(vinfo);
        mutex_unlock(&vinfo->lock);
        return rc;
}

static int hfi1_netdev_close(struct net_device *netdev)
{
        struct hfi1_vnic_vport_info *vinfo = opa_vnic_dev_priv(netdev);

        mutex_lock(&vinfo->lock);
        if (test_bit(HFI1_VNIC_UP, &vinfo->flags))
                hfi1_vnic_down(vinfo);
        mutex_unlock(&vinfo->lock);
        return 0;
}

static int hfi1_vnic_init(struct hfi1_vnic_vport_info *vinfo)
{
        struct hfi1_devdata *dd = vinfo->dd;
        int rc = 0;

        mutex_lock(&hfi1_mutex);
        if (!dd->vnic_num_vports) {
                rc = hfi1_vnic_txreq_init(dd);
                if (rc)
                        goto txreq_fail;
        }

        rc = hfi1_netdev_rx_init(dd);
        if (rc) {
                dd_dev_err(dd, "Unable to initialize netdev contexts\n");
                goto alloc_fail;
        }

        hfi1_init_vnic_rsm(dd);

        dd->vnic_num_vports++;
        hfi1_vnic_sdma_init(vinfo);

alloc_fail:
        if (!dd->vnic_num_vports)
                hfi1_vnic_txreq_deinit(dd);
txreq_fail:
        mutex_unlock(&hfi1_mutex);
        return rc;
}

static void hfi1_vnic_deinit(struct hfi1_vnic_vport_info *vinfo)
{
        struct hfi1_devdata *dd = vinfo->dd;

        mutex_lock(&hfi1_mutex);
        if (--dd->vnic_num_vports == 0) {
                hfi1_deinit_vnic_rsm(dd);
                hfi1_vnic_txreq_deinit(dd);
        }
        mutex_unlock(&hfi1_mutex);
        hfi1_netdev_rx_destroy(dd);
}

static void hfi1_vnic_set_vesw_id(struct net_device *netdev, int id)
{
        struct hfi1_vnic_vport_info *vinfo = opa_vnic_dev_priv(netdev);
        bool reopen = false;

        /*
         * If vesw_id is being changed, and if the vnic port is up,
         * reset the vnic port to ensure new vesw_id gets picked up
         */
        if (id != vinfo->vesw_id) {
                mutex_lock(&vinfo->lock);
                if (test_bit(HFI1_VNIC_UP, &vinfo->flags)) {
                        hfi1_vnic_down(vinfo);
                        reopen = true;
                }

                vinfo->vesw_id = id;
                if (reopen)
                        hfi1_vnic_up(vinfo);

                mutex_unlock(&vinfo->lock);
        }
}

/* netdev ops */
static const struct net_device_ops hfi1_netdev_ops = {
        .ndo_open = hfi1_netdev_open,
        .ndo_stop = hfi1_netdev_close,
        .ndo_start_xmit = hfi1_netdev_start_xmit,
        .ndo_select_queue = hfi1_vnic_select_queue,
        .ndo_get_stats64 = hfi1_vnic_get_stats64,
};

static void hfi1_vnic_free_rn(struct net_device *netdev)
{
        struct hfi1_vnic_vport_info *vinfo = opa_vnic_dev_priv(netdev);

        hfi1_vnic_deinit(vinfo);
        mutex_destroy(&vinfo->lock);
        free_netdev(netdev);
}

struct net_device *hfi1_vnic_alloc_rn(struct ib_device *device,
                                      u32 port_num,
                                      enum rdma_netdev_t type,
                                      const char *name,
                                      unsigned char name_assign_type,
                                      void (*setup)(struct net_device *))
{
        struct hfi1_devdata *dd = dd_from_ibdev(device);
        struct hfi1_vnic_vport_info *vinfo;
        struct net_device *netdev;
        struct rdma_netdev *rn;
        int i, size, rc;

        if (!dd->num_netdev_contexts)
                return ERR_PTR(-ENOMEM);

        if (!port_num || (port_num > dd->num_pports))
                return ERR_PTR(-EINVAL);

        if (type != RDMA_NETDEV_OPA_VNIC)
                return ERR_PTR(-EOPNOTSUPP);

        size = sizeof(struct opa_vnic_rdma_netdev) + sizeof(*vinfo);
        netdev = alloc_netdev_mqs(size, name, name_assign_type, setup,
                                  chip_sdma_engines(dd),
                                  dd->num_netdev_contexts);
        if (!netdev)
                return ERR_PTR(-ENOMEM);

        rn = netdev_priv(netdev);
        vinfo = opa_vnic_dev_priv(netdev);
        vinfo->dd = dd;
        vinfo->num_tx_q = chip_sdma_engines(dd);
        vinfo->num_rx_q = dd->num_netdev_contexts;
        vinfo->netdev = netdev;
        rn->free_rdma_netdev = hfi1_vnic_free_rn;
        rn->set_id = hfi1_vnic_set_vesw_id;

        netdev->features = NETIF_F_HIGHDMA | NETIF_F_SG;
        netdev->hw_features = netdev->features;
        netdev->vlan_features = netdev->features;
        netdev->watchdog_timeo = msecs_to_jiffies(HFI_TX_TIMEOUT_MS);
        netdev->netdev_ops = &hfi1_netdev_ops;
        mutex_init(&vinfo->lock);

        for (i = 0; i < vinfo->num_rx_q; i++) {
                struct hfi1_vnic_rx_queue *rxq = &vinfo->rxq[i];

                rxq->idx = i;
                rxq->vinfo = vinfo;
                rxq->netdev = netdev;
        }

        rc = hfi1_vnic_init(vinfo);
        if (rc)
                goto init_fail;

        return netdev;
init_fail:
        mutex_destroy(&vinfo->lock);
        free_netdev(netdev);
        return ERR_PTR(rc);
}