siena_sriov.c

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/****************************************************************************
 * Driver for Solarflare Solarstorm network controllers and boards
 * Copyright 2010-2011 Solarflare Communications Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation, incorporated herein by reference.
 */
#include <linux/pci.h>
#include <linux/module.h>
#include "net_driver.h"
#include "efx.h"
#include "nic.h"
#include "io.h"
#include "mcdi.h"
#include "filter.h"
#include "mcdi_pcol.h"
#include "regs.h"
#include "vfdi.h"

/* Number of longs required to track all the VIs in a VF */
#define VI_MASK_LENGTH BITS_TO_LONGS(1 << EFX_VI_SCALE_MAX)

/* Maximum number of RX queues supported */
#define VF_MAX_RX_QUEUES 63

enum efx_vf_tx_filter_mode {
    VF_TX_FILTER_OFF,
    VF_TX_FILTER_AUTO,
    VF_TX_FILTER_ON,
};

struct efx_vf {
    struct efx_nic *efx;
    unsigned int pci_rid;
    char pci_name[13]; /* dddd:bb:dd.f */
    unsigned int index;
    struct work_struct req;
    u64 req_addr;
    int req_type;
    unsigned req_seqno;
    unsigned msg_seqno;
    bool busy;
    struct efx_buffer buf;
    unsigned buftbl_base;
    bool rx_filtering;
    enum efx_filter_flags rx_filter_flags;
    unsigned rx_filter_qid;
    int rx_filter_id;
    enum efx_vf_tx_filter_mode tx_filter_mode;
    int tx_filter_id;
    struct vfdi_endpoint addr;
    u64 status_addr;
    struct mutex status_lock;
    u64 *peer_page_addrs;
    unsigned peer_page_count;
    u64 evq0_addrs[EFX_MAX_VF_EVQ_SIZE * sizeof(efx_qword_t) /
               EFX_BUF_SIZE];
    unsigned evq0_count;
    wait_queue_head_t flush_waitq;
    struct mutex txq_lock;
    unsigned long txq_mask[VI_MASK_LENGTH];
    unsigned txq_count;
    unsigned long rxq_mask[VI_MASK_LENGTH];
    unsigned rxq_count;
    unsigned long rxq_retry_mask[VI_MASK_LENGTH];
    atomic_t rxq_retry_count;
    struct work_struct reset_work;
};

struct efx_memcpy_req {
    unsigned int from_rid;
    void *from_buf;
    u64 from_addr;
    unsigned int to_rid;
    u64 to_addr;
    unsigned length;
};

struct efx_local_addr {
    struct list_head link;
    u8 addr[ETH_ALEN];
};

struct efx_endpoint_page {
    struct list_head link;
    void *ptr;
    dma_addr_t addr;
};

/* Buffer table entries are reserved txq0,rxq0,evq0,txq1,rxq1,evq1 */
#define EFX_BUFTBL_TXQ_BASE(_vf, _qid)                  \
    ((_vf)->buftbl_base + EFX_VF_BUFTBL_PER_VI * (_qid))
#define EFX_BUFTBL_RXQ_BASE(_vf, _qid)                  \
    (EFX_BUFTBL_TXQ_BASE(_vf, _qid) +               \
     (EFX_MAX_DMAQ_SIZE * sizeof(efx_qword_t) / EFX_BUF_SIZE))
#define EFX_BUFTBL_EVQ_BASE(_vf, _qid)                  \
    (EFX_BUFTBL_TXQ_BASE(_vf, _qid) +               \
     (2 * EFX_MAX_DMAQ_SIZE * sizeof(efx_qword_t) / EFX_BUF_SIZE))

#define EFX_FIELD_MASK(_field)          \
    ((1 << _field ## _WIDTH) - 1)

/* VFs can only use this many transmit channels */
static unsigned int vf_max_tx_channels = 2;
module_param(vf_max_tx_channels, uint, 0444);
MODULE_PARM_DESC(vf_max_tx_channels,
         "Limit the number of TX channels VFs can use");

static int max_vfs = -1;
module_param(max_vfs, int, 0444);
MODULE_PARM_DESC(max_vfs,
         "Reduce the number of VFs initialized by the driver");

/* Workqueue used by VFDI communication.  We can't use the global
 * workqueue because it may be running the VF driver's probe()
 * routine, which will be blocked there waiting for a VFDI response.
 */
static struct workqueue_struct *vfdi_workqueue;

static unsigned abs_index(struct efx_vf *vf, unsigned index)
{
    return EFX_VI_BASE + vf->index * efx_vf_size(vf->efx) + index;
}

static int efx_sriov_cmd(struct efx_nic *efx, bool enable,
             unsigned *vi_scale_out, unsigned *vf_total_out)
{
    u8 inbuf[MC_CMD_SRIOV_IN_LEN];
    u8 outbuf[MC_CMD_SRIOV_OUT_LEN];
    unsigned vi_scale, vf_total;
    size_t outlen;
    int rc;

    MCDI_SET_DWORD(inbuf, SRIOV_IN_ENABLE, enable ? 1 : 0);
    MCDI_SET_DWORD(inbuf, SRIOV_IN_VI_BASE, EFX_VI_BASE);
    MCDI_SET_DWORD(inbuf, SRIOV_IN_VF_COUNT, efx->vf_count);

    rc = efx_mcdi_rpc(efx, MC_CMD_SRIOV, inbuf, MC_CMD_SRIOV_IN_LEN,
              outbuf, MC_CMD_SRIOV_OUT_LEN, &outlen);
    if (rc)
        return rc;
    if (outlen < MC_CMD_SRIOV_OUT_LEN)
        return -EIO;

    vf_total = MCDI_DWORD(outbuf, SRIOV_OUT_VF_TOTAL);
    vi_scale = MCDI_DWORD(outbuf, SRIOV_OUT_VI_SCALE);
    if (vi_scale > EFX_VI_SCALE_MAX)
        return -EOPNOTSUPP;

    if (vi_scale_out)
        *vi_scale_out = vi_scale;
    if (vf_total_out)
        *vf_total_out = vf_total;

    return 0;
}

static void efx_sriov_usrev(struct efx_nic *efx, bool enabled)
{
    efx_oword_t reg;

    EFX_POPULATE_OWORD_2(reg,
                 FRF_CZ_USREV_DIS, enabled ? 0 : 1,
                 FRF_CZ_DFLT_EVQ, efx->vfdi_channel->channel);
    efx_writeo(efx, &reg, FR_CZ_USR_EV_CFG);
}

static int efx_sriov_memcpy(struct efx_nic *efx, struct efx_memcpy_req *req,
                unsigned int count)
{
    u8 *inbuf, *record;
    unsigned int used;
    u32 from_rid, from_hi, from_lo;
    int rc;

    mb();   /* Finish writing source/reading dest before DMA starts */

    used = MC_CMD_MEMCPY_IN_LEN(count);
    if (WARN_ON(used > MCDI_CTL_SDU_LEN_MAX))
        return -ENOBUFS;

    /* Allocate room for the largest request */
    inbuf = kzalloc(MCDI_CTL_SDU_LEN_MAX, GFP_KERNEL);
    if (inbuf == NULL)
        return -ENOMEM;

    record = inbuf;
    MCDI_SET_DWORD(record, MEMCPY_IN_RECORD, count);
    while (count-- > 0) {
        MCDI_SET_DWORD(record, MEMCPY_RECORD_TYPEDEF_TO_RID,
                   req->to_rid);
        MCDI_SET_DWORD(record, MEMCPY_RECORD_TYPEDEF_TO_ADDR_LO,
                   (u32)req->to_addr);
        MCDI_SET_DWORD(record, MEMCPY_RECORD_TYPEDEF_TO_ADDR_HI,
                   (u32)(req->to_addr >> 32));
        if (req->from_buf == NULL) {
            from_rid = req->from_rid;
            from_lo = (u32)req->from_addr;
            from_hi = (u32)(req->from_addr >> 32);
        } else {
            if (WARN_ON(used + req->length > MCDI_CTL_SDU_LEN_MAX)) {
                rc = -ENOBUFS;
                goto out;
            }

            from_rid = MC_CMD_MEMCPY_RECORD_TYPEDEF_RID_INLINE;
            from_lo = used;
            from_hi = 0;
            memcpy(inbuf + used, req->from_buf, req->length);
            used += req->length;
        }

        MCDI_SET_DWORD(record, MEMCPY_RECORD_TYPEDEF_FROM_RID, from_rid);
        MCDI_SET_DWORD(record, MEMCPY_RECORD_TYPEDEF_FROM_ADDR_LO,
                   from_lo);
        MCDI_SET_DWORD(record, MEMCPY_RECORD_TYPEDEF_FROM_ADDR_HI,
                   from_hi);
        MCDI_SET_DWORD(record, MEMCPY_RECORD_TYPEDEF_LENGTH,
                   req->length);

        ++req;
        record += MC_CMD_MEMCPY_IN_RECORD_LEN;
    }

    rc = efx_mcdi_rpc(efx, MC_CMD_MEMCPY, inbuf, used, NULL, 0, NULL);
out:
    kfree(inbuf);

    mb();   /* Don't write source/read dest before DMA is complete */

    return rc;
}

/* The TX filter is entirely controlled by this driver, and is modified
 * underneath the feet of the VF
 */
static void efx_sriov_reset_tx_filter(struct efx_vf *vf)
{
    struct efx_nic *efx = vf->efx;
    struct efx_filter_spec filter;
    u16 vlan;
    int rc;

    if (vf->tx_filter_id != -1) {
        efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED,
                      vf->tx_filter_id);
        netif_dbg(efx, hw, efx->net_dev, "Removed vf %s tx filter %d\n",
              vf->pci_name, vf->tx_filter_id);
        vf->tx_filter_id = -1;
    }

    if (is_zero_ether_addr(vf->addr.mac_addr))
        return;

    /* Turn on TX filtering automatically if not explicitly
     * enabled or disabled.
     */
    if (vf->tx_filter_mode == VF_TX_FILTER_AUTO && vf_max_tx_channels <= 2)
        vf->tx_filter_mode = VF_TX_FILTER_ON;

    vlan = ntohs(vf->addr.tci) & VLAN_VID_MASK;
    efx_filter_init_tx(&filter, abs_index(vf, 0));
    rc = efx_filter_set_eth_local(&filter,
                      vlan ? vlan : EFX_FILTER_VID_UNSPEC,
                      vf->addr.mac_addr);
    BUG_ON(rc);

    rc = efx_filter_insert_filter(efx, &filter, true);
    if (rc < 0) {
        netif_warn(efx, hw, efx->net_dev,
               "Unable to migrate tx filter for vf %s\n",
               vf->pci_name);
    } else {
        netif_dbg(efx, hw, efx->net_dev, "Inserted vf %s tx filter %d\n",
              vf->pci_name, rc);
        vf->tx_filter_id = rc;
    }
}

/* The RX filter is managed here on behalf of the VF driver */
static void efx_sriov_reset_rx_filter(struct efx_vf *vf)
{
    struct efx_nic *efx = vf->efx;
    struct efx_filter_spec filter;
    u16 vlan;
    int rc;

    if (vf->rx_filter_id != -1) {
        efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED,
                      vf->rx_filter_id);
        netif_dbg(efx, hw, efx->net_dev, "Removed vf %s rx filter %d\n",
              vf->pci_name, vf->rx_filter_id);
        vf->rx_filter_id = -1;
    }

    if (!vf->rx_filtering || is_zero_ether_addr(vf->addr.mac_addr))
        return;

    vlan = ntohs(vf->addr.tci) & VLAN_VID_MASK;
    efx_filter_init_rx(&filter, EFX_FILTER_PRI_REQUIRED,
               vf->rx_filter_flags,
               abs_index(vf, vf->rx_filter_qid));
    rc = efx_filter_set_eth_local(&filter,
                      vlan ? vlan : EFX_FILTER_VID_UNSPEC,
                      vf->addr.mac_addr);
    BUG_ON(rc);

    rc = efx_filter_insert_filter(efx, &filter, true);
    if (rc < 0) {
        netif_warn(efx, hw, efx->net_dev,
               "Unable to insert rx filter for vf %s\n",
               vf->pci_name);
    } else {
        netif_dbg(efx, hw, efx->net_dev, "Inserted vf %s rx filter %d\n",
              vf->pci_name, rc);
        vf->rx_filter_id = rc;
    }
}

static void __efx_sriov_update_vf_addr(struct efx_vf *vf)
{
    efx_sriov_reset_tx_filter(vf);
    efx_sriov_reset_rx_filter(vf);
    queue_work(vfdi_workqueue, &vf->efx->peer_work);
}

/* Push the peer list to this VF. The caller must hold status_lock to interlock
 * with VFDI requests, and they must be serialised against manipulation of
 * local_page_list, either by acquiring local_lock or by running from
 * efx_sriov_peer_work()
 */
static void __efx_sriov_push_vf_status(struct efx_vf *vf)
{
    struct efx_nic *efx = vf->efx;
    struct vfdi_status *status = efx->vfdi_status.addr;
    struct efx_memcpy_req copy[4];
    struct efx_endpoint_page *epp;
    unsigned int pos, count;
    unsigned data_offset;
    efx_qword_t event;

    WARN_ON(!mutex_is_locked(&vf->status_lock));
    WARN_ON(!vf->status_addr);

    status->local = vf->addr;
    status->generation_end = ++status->generation_start;

    memset(copy, '\0', sizeof(copy));
    /* Write generation_start */
    copy[0].from_buf = &status->generation_start;
    copy[0].to_rid = vf->pci_rid;
    copy[0].to_addr = vf->status_addr + offsetof(struct vfdi_status,
                             generation_start);
    copy[0].length = sizeof(status->generation_start);
    /* DMA the rest of the structure (excluding the generations). This
     * assumes that the non-generation portion of vfdi_status is in
     * one chunk starting at the version member.
     */
    data_offset = offsetof(struct vfdi_status, version);
    copy[1].from_rid = efx->pci_dev->devfn;
    copy[1].from_addr = efx->vfdi_status.dma_addr + data_offset;
    copy[1].to_rid = vf->pci_rid;
    copy[1].to_addr = vf->status_addr + data_offset;
    copy[1].length =  status->length - data_offset;

    /* Copy the peer pages */
    pos = 2;
    count = 0;
    list_for_each_entry(epp, &efx->local_page_list, link) {
        if (count == vf->peer_page_count) {
            /* The VF driver will know they need to provide more
             * pages because peer_addr_count is too large.
             */
            break;
        }
        copy[pos].from_buf = NULL;
        copy[pos].from_rid = efx->pci_dev->devfn;
        copy[pos].from_addr = epp->addr;
        copy[pos].to_rid = vf->pci_rid;
        copy[pos].to_addr = vf->peer_page_addrs[count];
        copy[pos].length = EFX_PAGE_SIZE;

        if (++pos == ARRAY_SIZE(copy)) {
            efx_sriov_memcpy(efx, copy, ARRAY_SIZE(copy));
            pos = 0;
        }
        ++count;
    }

    /* Write generation_end */
    copy[pos].from_buf = &status->generation_end;
    copy[pos].to_rid = vf->pci_rid;
    copy[pos].to_addr = vf->status_addr + offsetof(struct vfdi_status,
                               generation_end);
    copy[pos].length = sizeof(status->generation_end);
    efx_sriov_memcpy(efx, copy, pos + 1);

    /* Notify the guest */
    EFX_POPULATE_QWORD_3(event,
                 FSF_AZ_EV_CODE, FSE_CZ_EV_CODE_USER_EV,
                 VFDI_EV_SEQ, (vf->msg_seqno & 0xff),
                 VFDI_EV_TYPE, VFDI_EV_TYPE_STATUS);
    ++vf->msg_seqno;
    efx_generate_event(efx, EFX_VI_BASE + vf->index * efx_vf_size(efx),
                  &event);
}

static void efx_sriov_bufs(struct efx_nic *efx, unsigned offset,
               u64 *addr, unsigned count)
{
    efx_qword_t buf;
    unsigned pos;

    for (pos = 0; pos < count; ++pos) {
        EFX_POPULATE_QWORD_3(buf,
                     FRF_AZ_BUF_ADR_REGION, 0,
                     FRF_AZ_BUF_ADR_FBUF,
                     addr ? addr[pos] >> 12 : 0,
                     FRF_AZ_BUF_OWNER_ID_FBUF, 0);
        efx_sram_writeq(efx, efx->membase + FR_BZ_BUF_FULL_TBL,
                &buf, offset + pos);
    }
}

static bool bad_vf_index(struct efx_nic *efx, unsigned index)
{
    return index >= efx_vf_size(efx);
}

static bool bad_buf_count(unsigned buf_count, unsigned max_entry_count)
{
    unsigned max_buf_count = max_entry_count *
        sizeof(efx_qword_t) / EFX_BUF_SIZE;

    return ((buf_count & (buf_count - 1)) || buf_count > max_buf_count);
}

/* Check that VI specified by per-port index belongs to a VF.
 * Optionally set VF index and VI index within the VF.
 */
static bool map_vi_index(struct efx_nic *efx, unsigned abs_index,
             struct efx_vf **vf_out, unsigned *rel_index_out)
{
    unsigned vf_i;

    if (abs_index < EFX_VI_BASE)
        return true;
    vf_i = (abs_index - EFX_VI_BASE) / efx_vf_size(efx);
    if (vf_i >= efx->vf_init_count)
        return true;

    if (vf_out)
        *vf_out = efx->vf + vf_i;
    if (rel_index_out)
        *rel_index_out = abs_index % efx_vf_size(efx);
    return false;
}

static int efx_vfdi_init_evq(struct efx_vf *vf)
{
    struct efx_nic *efx = vf->efx;
    struct vfdi_req *req = vf->buf.addr;
    unsigned vf_evq = req->u.init_evq.index;
    unsigned buf_count = req->u.init_evq.buf_count;
    unsigned abs_evq = abs_index(vf, vf_evq);
    unsigned buftbl = EFX_BUFTBL_EVQ_BASE(vf, vf_evq);
    efx_oword_t reg;

    if (bad_vf_index(efx, vf_evq) ||
        bad_buf_count(buf_count, EFX_MAX_VF_EVQ_SIZE)) {
        if (net_ratelimit())
            netif_err(efx, hw, efx->net_dev,
                  "ERROR: Invalid INIT_EVQ from %s: evq %d bufs %d\n",
                  vf->pci_name, vf_evq, buf_count);
        return VFDI_RC_EINVAL;
    }

    efx_sriov_bufs(efx, buftbl, req->u.init_evq.addr, buf_count);

    EFX_POPULATE_OWORD_3(reg,
                 FRF_CZ_TIMER_Q_EN, 1,
                 FRF_CZ_HOST_NOTIFY_MODE, 0,
                 FRF_CZ_TIMER_MODE, FFE_CZ_TIMER_MODE_DIS);
    efx_writeo_table(efx, &reg, FR_BZ_TIMER_TBL, abs_evq);
    EFX_POPULATE_OWORD_3(reg,
                 FRF_AZ_EVQ_EN, 1,
                 FRF_AZ_EVQ_SIZE, __ffs(buf_count),
                 FRF_AZ_EVQ_BUF_BASE_ID, buftbl);
    efx_writeo_table(efx, &reg, FR_BZ_EVQ_PTR_TBL, abs_evq);

    if (vf_evq == 0) {
        memcpy(vf->evq0_addrs, req->u.init_evq.addr,
               buf_count * sizeof(u64));
        vf->evq0_count = buf_count;
    }

    return VFDI_RC_SUCCESS;
}

static int efx_vfdi_init_rxq(struct efx_vf *vf)
{
    struct efx_nic *efx = vf->efx;
    struct vfdi_req *req = vf->buf.addr;
    unsigned vf_rxq = req->u.init_rxq.index;
    unsigned vf_evq = req->u.init_rxq.evq;
    unsigned buf_count = req->u.init_rxq.buf_count;
    unsigned buftbl = EFX_BUFTBL_RXQ_BASE(vf, vf_rxq);
    unsigned label;
    efx_oword_t reg;

    if (bad_vf_index(efx, vf_evq) || bad_vf_index(efx, vf_rxq) ||
        vf_rxq >= VF_MAX_RX_QUEUES ||
        bad_buf_count(buf_count, EFX_MAX_DMAQ_SIZE)) {
        if (net_ratelimit())
            netif_err(efx, hw, efx->net_dev,
                  "ERROR: Invalid INIT_RXQ from %s: rxq %d evq %d "
                  "buf_count %d\n", vf->pci_name, vf_rxq,
                  vf_evq, buf_count);
        return VFDI_RC_EINVAL;
    }
    if (__test_and_set_bit(req->u.init_rxq.index, vf->rxq_mask))
        ++vf->rxq_count;
    efx_sriov_bufs(efx, buftbl, req->u.init_rxq.addr, buf_count);

    label = req->u.init_rxq.label & EFX_FIELD_MASK(FRF_AZ_RX_DESCQ_LABEL);
    EFX_POPULATE_OWORD_6(reg,
                 FRF_AZ_RX_DESCQ_BUF_BASE_ID, buftbl,
                 FRF_AZ_RX_DESCQ_EVQ_ID, abs_index(vf, vf_evq),
                 FRF_AZ_RX_DESCQ_LABEL, label,
                 FRF_AZ_RX_DESCQ_SIZE, __ffs(buf_count),
                 FRF_AZ_RX_DESCQ_JUMBO,
                 !!(req->u.init_rxq.flags &
                VFDI_RXQ_FLAG_SCATTER_EN),
                 FRF_AZ_RX_DESCQ_EN, 1);
    efx_writeo_table(efx, &reg, FR_BZ_RX_DESC_PTR_TBL,
             abs_index(vf, vf_rxq));

    return VFDI_RC_SUCCESS;
}

static int efx_vfdi_init_txq(struct efx_vf *vf)
{
    struct efx_nic *efx = vf->efx;
    struct vfdi_req *req = vf->buf.addr;
    unsigned vf_txq = req->u.init_txq.index;
    unsigned vf_evq = req->u.init_txq.evq;
    unsigned buf_count = req->u.init_txq.buf_count;
    unsigned buftbl = EFX_BUFTBL_TXQ_BASE(vf, vf_txq);
    unsigned label, eth_filt_en;
    efx_oword_t reg;

    if (bad_vf_index(efx, vf_evq) || bad_vf_index(efx, vf_txq) ||
        vf_txq >= vf_max_tx_channels ||
        bad_buf_count(buf_count, EFX_MAX_DMAQ_SIZE)) {
        if (net_ratelimit())
            netif_err(efx, hw, efx->net_dev,
                  "ERROR: Invalid INIT_TXQ from %s: txq %d evq %d "
                  "buf_count %d\n", vf->pci_name, vf_txq,
                  vf_evq, buf_count);
        return VFDI_RC_EINVAL;
    }

    mutex_lock(&vf->txq_lock);
    if (__test_and_set_bit(req->u.init_txq.index, vf->txq_mask))
        ++vf->txq_count;
    mutex_unlock(&vf->txq_lock);
    efx_sriov_bufs(efx, buftbl, req->u.init_txq.addr, buf_count);

    eth_filt_en = vf->tx_filter_mode == VF_TX_FILTER_ON;

    label = req->u.init_txq.label & EFX_FIELD_MASK(FRF_AZ_TX_DESCQ_LABEL);
    EFX_POPULATE_OWORD_8(reg,
                 FRF_CZ_TX_DPT_Q_MASK_WIDTH, min(efx->vi_scale, 1U),
                 FRF_CZ_TX_DPT_ETH_FILT_EN, eth_filt_en,
                 FRF_AZ_TX_DESCQ_EN, 1,
                 FRF_AZ_TX_DESCQ_BUF_BASE_ID, buftbl,
                 FRF_AZ_TX_DESCQ_EVQ_ID, abs_index(vf, vf_evq),
                 FRF_AZ_TX_DESCQ_LABEL, label,
                 FRF_AZ_TX_DESCQ_SIZE, __ffs(buf_count),
                 FRF_BZ_TX_NON_IP_DROP_DIS, 1);
    efx_writeo_table(efx, &reg, FR_BZ_TX_DESC_PTR_TBL,
             abs_index(vf, vf_txq));

    return VFDI_RC_SUCCESS;
}

/* Returns true when efx_vfdi_fini_all_queues should wake */
static bool efx_vfdi_flush_wake(struct efx_vf *vf)
{
    /* Ensure that all updates are visible to efx_vfdi_fini_all_queues() */
    smp_mb();

    return (!vf->txq_count && !vf->rxq_count) ||
        atomic_read(&vf->rxq_retry_count);
}

static void efx_vfdi_flush_clear(struct efx_vf *vf)
{
    memset(vf->txq_mask, 0, sizeof(vf->txq_mask));
    vf->txq_count = 0;
    memset(vf->rxq_mask, 0, sizeof(vf->rxq_mask));
    vf->rxq_count = 0;
    memset(vf->rxq_retry_mask, 0, sizeof(vf->rxq_retry_mask));
    atomic_set(&vf->rxq_retry_count, 0);
}

static int efx_vfdi_fini_all_queues(struct efx_vf *vf)
{
    struct efx_nic *efx = vf->efx;
    efx_oword_t reg;
    unsigned count = efx_vf_size(efx);
    unsigned vf_offset = EFX_VI_BASE + vf->index * efx_vf_size(efx);
    unsigned timeout = HZ;
    unsigned index, rxqs_count;
    __le32 *rxqs;
    int rc;

    BUILD_BUG_ON(VF_MAX_RX_QUEUES >
             MC_CMD_FLUSH_RX_QUEUES_IN_QID_OFST_MAXNUM);

    rxqs = kmalloc(count * sizeof(*rxqs), GFP_KERNEL);
    if (rxqs == NULL)
        return VFDI_RC_ENOMEM;

    rtnl_lock();
    if (efx->fc_disable++ == 0)
        efx_mcdi_set_mac(efx);
    rtnl_unlock();

    /* Flush all the initialized queues */
    rxqs_count = 0;
    for (index = 0; index < count; ++index) {
        if (test_bit(index, vf->txq_mask)) {
            EFX_POPULATE_OWORD_2(reg,
                         FRF_AZ_TX_FLUSH_DESCQ_CMD, 1,
                         FRF_AZ_TX_FLUSH_DESCQ,
                         vf_offset + index);
            efx_writeo(efx, &reg, FR_AZ_TX_FLUSH_DESCQ);
        }
        if (test_bit(index, vf->rxq_mask))
            rxqs[rxqs_count++] = cpu_to_le32(vf_offset + index);
    }

    atomic_set(&vf->rxq_retry_count, 0);
    while (timeout && (vf->rxq_count || vf->txq_count)) {
        rc = efx_mcdi_rpc(efx, MC_CMD_FLUSH_RX_QUEUES, (u8 *)rxqs,
                  rxqs_count * sizeof(*rxqs), NULL, 0, NULL);
        WARN_ON(rc < 0);

        timeout = wait_event_timeout(vf->flush_waitq,
                         efx_vfdi_flush_wake(vf),
                         timeout);
        rxqs_count = 0;
        for (index = 0; index < count; ++index) {
            if (test_and_clear_bit(index, vf->rxq_retry_mask)) {
                atomic_dec(&vf->rxq_retry_count);
                rxqs[rxqs_count++] =
                    cpu_to_le32(vf_offset + index);
            }
        }
    }

    rtnl_lock();
    if (--efx->fc_disable == 0)
        efx_mcdi_set_mac(efx);
    rtnl_unlock();

    /* Irrespective of success/failure, fini the queues */
    EFX_ZERO_OWORD(reg);
    for (index = 0; index < count; ++index) {
        efx_writeo_table(efx, &reg, FR_BZ_RX_DESC_PTR_TBL,
                 vf_offset + index);
        efx_writeo_table(efx, &reg, FR_BZ_TX_DESC_PTR_TBL,
                 vf_offset + index);
        efx_writeo_table(efx, &reg, FR_BZ_EVQ_PTR_TBL,
                 vf_offset + index);
        efx_writeo_table(efx, &reg, FR_BZ_TIMER_TBL,
                 vf_offset + index);
    }
    efx_sriov_bufs(efx, vf->buftbl_base, NULL,
               EFX_VF_BUFTBL_PER_VI * efx_vf_size(efx));
    kfree(rxqs);
    efx_vfdi_flush_clear(vf);

    vf->evq0_count = 0;

    return timeout ? 0 : VFDI_RC_ETIMEDOUT;
}

static int efx_vfdi_insert_filter(struct efx_vf *vf)
{
    struct efx_nic *efx = vf->efx;
    struct vfdi_req *req = vf->buf.addr;
    unsigned vf_rxq = req->u.mac_filter.rxq;
    unsigned flags;

    if (bad_vf_index(efx, vf_rxq) || vf->rx_filtering) {
        if (net_ratelimit())
            netif_err(efx, hw, efx->net_dev,
                  "ERROR: Invalid INSERT_FILTER from %s: rxq %d "
                  "flags 0x%x\n", vf->pci_name, vf_rxq,
                  req->u.mac_filter.flags);
        return VFDI_RC_EINVAL;
    }

    flags = 0;
    if (req->u.mac_filter.flags & VFDI_MAC_FILTER_FLAG_RSS)
        flags |= EFX_FILTER_FLAG_RX_RSS;
    if (req->u.mac_filter.flags & VFDI_MAC_FILTER_FLAG_SCATTER)
        flags |= EFX_FILTER_FLAG_RX_SCATTER;
    vf->rx_filter_flags = flags;
    vf->rx_filter_qid = vf_rxq;
    vf->rx_filtering = true;

    efx_sriov_reset_rx_filter(vf);
    queue_work(vfdi_workqueue, &efx->peer_work);

    return VFDI_RC_SUCCESS;
}

static int efx_vfdi_remove_all_filters(struct efx_vf *vf)
{
    vf->rx_filtering = false;
    efx_sriov_reset_rx_filter(vf);
    queue_work(vfdi_workqueue, &vf->efx->peer_work);

    return VFDI_RC_SUCCESS;
}

static int efx_vfdi_set_status_page(struct efx_vf *vf)
{
    struct efx_nic *efx = vf->efx;
    struct vfdi_req *req = vf->buf.addr;
    u64 page_count = req->u.set_status_page.peer_page_count;
    u64 max_page_count =
        (EFX_PAGE_SIZE -
         offsetof(struct vfdi_req, u.set_status_page.peer_page_addr[0]))
        / sizeof(req->u.set_status_page.peer_page_addr[0]);

    if (!req->u.set_status_page.dma_addr || page_count > max_page_count) {
        if (net_ratelimit())
            netif_err(efx, hw, efx->net_dev,
                  "ERROR: Invalid SET_STATUS_PAGE from %s\n",
                  vf->pci_name);
        return VFDI_RC_EINVAL;
    }

    mutex_lock(&efx->local_lock);
    mutex_lock(&vf->status_lock);
    vf->status_addr = req->u.set_status_page.dma_addr;

    kfree(vf->peer_page_addrs);
    vf->peer_page_addrs = NULL;
    vf->peer_page_count = 0;

    if (page_count) {
        vf->peer_page_addrs = kcalloc(page_count, sizeof(u64),
                          GFP_KERNEL);
        if (vf->peer_page_addrs) {
            memcpy(vf->peer_page_addrs,
                   req->u.set_status_page.peer_page_addr,
                   page_count * sizeof(u64));
            vf->peer_page_count = page_count;
        }
    }

    __efx_sriov_push_vf_status(vf);
    mutex_unlock(&vf->status_lock);
    mutex_unlock(&efx->local_lock);

    return VFDI_RC_SUCCESS;
}

static int efx_vfdi_clear_status_page(struct efx_vf *vf)
{
    mutex_lock(&vf->status_lock);
    vf->status_addr = 0;
    mutex_unlock(&vf->status_lock);

    return VFDI_RC_SUCCESS;
}

typedef int (*efx_vfdi_op_t)(struct efx_vf *vf);

static const efx_vfdi_op_t vfdi_ops[VFDI_OP_LIMIT] = {
    [VFDI_OP_INIT_EVQ] = efx_vfdi_init_evq,
    [VFDI_OP_INIT_TXQ] = efx_vfdi_init_txq,
    [VFDI_OP_INIT_RXQ] = efx_vfdi_init_rxq,
    [VFDI_OP_FINI_ALL_QUEUES] = efx_vfdi_fini_all_queues,
    [VFDI_OP_INSERT_FILTER] = efx_vfdi_insert_filter,
    [VFDI_OP_REMOVE_ALL_FILTERS] = efx_vfdi_remove_all_filters,
    [VFDI_OP_SET_STATUS_PAGE] = efx_vfdi_set_status_page,
    [VFDI_OP_CLEAR_STATUS_PAGE] = efx_vfdi_clear_status_page,
};

static void efx_sriov_vfdi(struct work_struct *work)
{
    struct efx_vf *vf = container_of(work, struct efx_vf, req);
    struct efx_nic *efx = vf->efx;
    struct vfdi_req *req = vf->buf.addr;
    struct efx_memcpy_req copy[2];
    int rc;

    /* Copy this page into the local address space */
    memset(copy, '\0', sizeof(copy));
    copy[0].from_rid = vf->pci_rid;
    copy[0].from_addr = vf->req_addr;
    copy[0].to_rid = efx->pci_dev->devfn;
    copy[0].to_addr = vf->buf.dma_addr;
    copy[0].length = EFX_PAGE_SIZE;
    rc = efx_sriov_memcpy(efx, copy, 1);
    if (rc) {
        /* If we can't get the request, we can't reply to the caller */
        if (net_ratelimit())
            netif_err(efx, hw, efx->net_dev,
                  "ERROR: Unable to fetch VFDI request from %s rc %d\n",
                  vf->pci_name, -rc);
        vf->busy = false;
        return;
    }

    if (req->op < VFDI_OP_LIMIT && vfdi_ops[req->op] != NULL) {
        rc = vfdi_ops[req->op](vf);
        if (rc == 0) {
            netif_dbg(efx, hw, efx->net_dev,
                  "vfdi request %d from %s ok\n",
                  req->op, vf->pci_name);
        }
    } else {
        netif_dbg(efx, hw, efx->net_dev,
              "ERROR: Unrecognised request %d from VF %s addr "
              "%llx\n", req->op, vf->pci_name,
              (unsigned long long)vf->req_addr);
        rc = VFDI_RC_EOPNOTSUPP;
    }

    /* Allow subsequent VF requests */
    vf->busy = false;
    smp_wmb();

    /* Respond to the request */
    req->rc = rc;
    req->op = VFDI_OP_RESPONSE;

    memset(copy, '\0', sizeof(copy));
    copy[0].from_buf = &req->rc;
    copy[0].to_rid = vf->pci_rid;
    copy[0].to_addr = vf->req_addr + offsetof(struct vfdi_req, rc);
    copy[0].length = sizeof(req->rc);
    copy[1].from_buf = &req->op;
    copy[1].to_rid = vf->pci_rid;
    copy[1].to_addr = vf->req_addr + offsetof(struct vfdi_req, op);
    copy[1].length = sizeof(req->op);

    (void) efx_sriov_memcpy(efx, copy, ARRAY_SIZE(copy));
}



/* After a reset the event queues inside the guests no longer exist. Fill the
 * event ring in guest memory with VFDI reset events, then (re-initialise) the
 * event queue to raise an interrupt. The guest driver will then recover.
 */
static void efx_sriov_reset_vf(struct efx_vf *vf, struct efx_buffer *buffer)
{
    struct efx_nic *efx = vf->efx;
    struct efx_memcpy_req copy_req[4];
    efx_qword_t event;
    unsigned int pos, count, k, buftbl, abs_evq;
    efx_oword_t reg;
    efx_dword_t ptr;
    int rc;

    BUG_ON(buffer->len != EFX_PAGE_SIZE);

    if (!vf->evq0_count)
        return;
    BUG_ON(vf->evq0_count & (vf->evq0_count - 1));

    mutex_lock(&vf->status_lock);
    EFX_POPULATE_QWORD_3(event,
                 FSF_AZ_EV_CODE, FSE_CZ_EV_CODE_USER_EV,
                 VFDI_EV_SEQ, vf->msg_seqno,
                 VFDI_EV_TYPE, VFDI_EV_TYPE_RESET);
    vf->msg_seqno++;
    for (pos = 0; pos < EFX_PAGE_SIZE; pos += sizeof(event))
        memcpy(buffer->addr + pos, &event, sizeof(event));

    for (pos = 0; pos < vf->evq0_count; pos += count) {
        count = min_t(unsigned, vf->evq0_count - pos,
                  ARRAY_SIZE(copy_req));
        for (k = 0; k < count; k++) {
            copy_req[k].from_buf = NULL;
            copy_req[k].from_rid = efx->pci_dev->devfn;
            copy_req[k].from_addr = buffer->dma_addr;
            copy_req[k].to_rid = vf->pci_rid;
            copy_req[k].to_addr = vf->evq0_addrs[pos + k];
            copy_req[k].length = EFX_PAGE_SIZE;
        }
        rc = efx_sriov_memcpy(efx, copy_req, count);
        if (rc) {
            if (net_ratelimit())
                netif_err(efx, hw, efx->net_dev,
                      "ERROR: Unable to notify %s of reset"
                      ": %d\n", vf->pci_name, -rc);
            break;
        }
    }

    /* Reinitialise, arm and trigger evq0 */
    abs_evq = abs_index(vf, 0);
    buftbl = EFX_BUFTBL_EVQ_BASE(vf, 0);
    efx_sriov_bufs(efx, buftbl, vf->evq0_addrs, vf->evq0_count);

    EFX_POPULATE_OWORD_3(reg,
                 FRF_CZ_TIMER_Q_EN, 1,
                 FRF_CZ_HOST_NOTIFY_MODE, 0,
                 FRF_CZ_TIMER_MODE, FFE_CZ_TIMER_MODE_DIS);
    efx_writeo_table(efx, &reg, FR_BZ_TIMER_TBL, abs_evq);
    EFX_POPULATE_OWORD_3(reg,
                 FRF_AZ_EVQ_EN, 1,
                 FRF_AZ_EVQ_SIZE, __ffs(vf->evq0_count),
                 FRF_AZ_EVQ_BUF_BASE_ID, buftbl);
    efx_writeo_table(efx, &reg, FR_BZ_EVQ_PTR_TBL, abs_evq);
    EFX_POPULATE_DWORD_1(ptr, FRF_AZ_EVQ_RPTR, 0);
    efx_writed_table(efx, &ptr, FR_BZ_EVQ_RPTR, abs_evq);

    mutex_unlock(&vf->status_lock);
}

static void efx_sriov_reset_vf_work(struct work_struct *work)
{
    struct efx_vf *vf = container_of(work, struct efx_vf, req);
    struct efx_nic *efx = vf->efx;
    struct efx_buffer buf;

    if (!efx_nic_alloc_buffer(efx, &buf, EFX_PAGE_SIZE)) {
        efx_sriov_reset_vf(vf, &buf);
        efx_nic_free_buffer(efx, &buf);
    }
}

static void efx_sriov_handle_no_channel(struct efx_nic *efx)
{
    netif_err(efx, drv, efx->net_dev,
          "ERROR: IOV requires MSI-X and 1 additional interrupt"
          "vector. IOV disabled\n");
    efx->vf_count = 0;
}

static int efx_sriov_probe_channel(struct efx_channel *channel)
{
    channel->efx->vfdi_channel = channel;
    return 0;
}

static void
efx_sriov_get_channel_name(struct efx_channel *channel, char *buf, size_t len)
{
    snprintf(buf, len, "%s-iov", channel->efx->name);
}

static const struct efx_channel_type efx_sriov_channel_type = {
    .handle_no_channel  = efx_sriov_handle_no_channel,
    .pre_probe      = efx_sriov_probe_channel,
    .post_remove        = efx_channel_dummy_op_void,
    .get_name       = efx_sriov_get_channel_name,
    /* no copy operation; channel must not be reallocated */
    .keep_eventq        = true,
};

void efx_sriov_probe(struct efx_nic *efx)
{
    unsigned count;

    if (!max_vfs)
        return;

    if (efx_sriov_cmd(efx, false, &efx->vi_scale, &count))
        return;
    if (count > 0 && count > max_vfs)
        count = max_vfs;

    /* efx_nic_dimension_resources() will reduce vf_count as appopriate */
    efx->vf_count = count;

    efx->extra_channel_type[EFX_EXTRA_CHANNEL_IOV] = &efx_sriov_channel_type;
}

/* Copy the list of individual addresses into the vfdi_status.peers
 * array and auxillary pages, protected by %local_lock. Drop that lock
 * and then broadcast the address list to every VF.
 */
static void efx_sriov_peer_work(struct work_struct *data)
{
    struct efx_nic *efx = container_of(data, struct efx_nic, peer_work);
    struct vfdi_status *vfdi_status = efx->vfdi_status.addr;
    struct efx_vf *vf;
    struct efx_local_addr *local_addr;
    struct vfdi_endpoint *peer;
    struct efx_endpoint_page *epp;
    struct list_head pages;
    unsigned int peer_space;
    unsigned int peer_count;
    unsigned int pos;

    mutex_lock(&efx->local_lock);

    /* Move the existing peer pages off %local_page_list */
    INIT_LIST_HEAD(&pages);
    list_splice_tail_init(&efx->local_page_list, &pages);

    /* Populate the VF addresses starting from entry 1 (entry 0 is
     * the PF address)
     */
    peer = vfdi_status->peers + 1;
    peer_space = ARRAY_SIZE(vfdi_status->peers) - 1;
    peer_count = 1;
    for (pos = 0; pos < efx->vf_count; ++pos) {
        vf = efx->vf + pos;

        mutex_lock(&vf->status_lock);
        if (vf->rx_filtering && !is_zero_ether_addr(vf->addr.mac_addr)) {
            *peer++ = vf->addr;
            ++peer_count;
            --peer_space;
            BUG_ON(peer_space == 0);
        }
        mutex_unlock(&vf->status_lock);
    }

    /* Fill the remaining addresses */
    list_for_each_entry(local_addr, &efx->local_addr_list, link) {
        memcpy(peer->mac_addr, local_addr->addr, ETH_ALEN);
        peer->tci = 0;
        ++peer;
        ++peer_count;
        if (--peer_space == 0) {
            if (list_empty(&pages)) {
                epp = kmalloc(sizeof(*epp), GFP_KERNEL);
                if (!epp)
                    break;
                epp->ptr = dma_alloc_coherent(
                    &efx->pci_dev->dev, EFX_PAGE_SIZE,
                    &epp->addr, GFP_KERNEL);
                if (!epp->ptr) {
                    kfree(epp);
                    break;
                }
            } else {
                epp = list_first_entry(
                    &pages, struct efx_endpoint_page, link);
                list_del(&epp->link);
            }

            list_add_tail(&epp->link, &efx->local_page_list);
            peer = (struct vfdi_endpoint *)epp->ptr;
            peer_space = EFX_PAGE_SIZE / sizeof(struct vfdi_endpoint);
        }
    }
    vfdi_status->peer_count = peer_count;
    mutex_unlock(&efx->local_lock);

    /* Free any now unused endpoint pages */
    while (!list_empty(&pages)) {
        epp = list_first_entry(
            &pages, struct efx_endpoint_page, link);
        list_del(&epp->link);
        dma_free_coherent(&efx->pci_dev->dev, EFX_PAGE_SIZE,
                  epp->ptr, epp->addr);
        kfree(epp);
    }

    /* Finally, push the pages */
    for (pos = 0; pos < efx->vf_count; ++pos) {
        vf = efx->vf + pos;

        mutex_lock(&vf->status_lock);
        if (vf->status_addr)
            __efx_sriov_push_vf_status(vf);
        mutex_unlock(&vf->status_lock);
    }
}

static void efx_sriov_free_local(struct efx_nic *efx)
{
    struct efx_local_addr *local_addr;
    struct efx_endpoint_page *epp;

    while (!list_empty(&efx->local_addr_list)) {
        local_addr = list_first_entry(&efx->local_addr_list,
                          struct efx_local_addr, link);
        list_del(&local_addr->link);
        kfree(local_addr);
    }

    while (!list_empty(&efx->local_page_list)) {
        epp = list_first_entry(&efx->local_page_list,
                       struct efx_endpoint_page, link);
        list_del(&epp->link);
        dma_free_coherent(&efx->pci_dev->dev, EFX_PAGE_SIZE,
                  epp->ptr, epp->addr);
        kfree(epp);
    }
}

static int efx_sriov_vf_alloc(struct efx_nic *efx)
{
    unsigned index;
    struct efx_vf *vf;

    efx->vf = kzalloc(sizeof(struct efx_vf) * efx->vf_count, GFP_KERNEL);
    if (!efx->vf)
        return -ENOMEM;

    for (index = 0; index < efx->vf_count; ++index) {
        vf = efx->vf + index;

        vf->efx = efx;
        vf->index = index;
        vf->rx_filter_id = -1;
        vf->tx_filter_mode = VF_TX_FILTER_AUTO;
        vf->tx_filter_id = -1;
        INIT_WORK(&vf->req, efx_sriov_vfdi);
        INIT_WORK(&vf->reset_work, efx_sriov_reset_vf_work);
        init_waitqueue_head(&vf->flush_waitq);
        mutex_init(&vf->status_lock);
        mutex_init(&vf->txq_lock);
    }

    return 0;
}

static void efx_sriov_vfs_fini(struct efx_nic *efx)
{
    struct efx_vf *vf;
    unsigned int pos;

    for (pos = 0; pos < efx->vf_count; ++pos) {
        vf = efx->vf + pos;

        efx_nic_free_buffer(efx, &vf->buf);
        kfree(vf->peer_page_addrs);
        vf->peer_page_addrs = NULL;
        vf->peer_page_count = 0;

        vf->evq0_count = 0;
    }
}

static int efx_sriov_vfs_init(struct efx_nic *efx)
{
    struct pci_dev *pci_dev = efx->pci_dev;
    unsigned index, devfn, sriov, buftbl_base;
    u16 offset, stride;
    struct efx_vf *vf;
    int rc;

    sriov = pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV);
    if (!sriov)
        return -ENOENT;

    pci_read_config_word(pci_dev, sriov + PCI_SRIOV_VF_OFFSET, &offset);
    pci_read_config_word(pci_dev, sriov + PCI_SRIOV_VF_STRIDE, &stride);

    buftbl_base = efx->vf_buftbl_base;
    devfn = pci_dev->devfn + offset;
    for (index = 0; index < efx->vf_count; ++index) {
        vf = efx->vf + index;

        /* Reserve buffer entries */
        vf->buftbl_base = buftbl_base;
        buftbl_base += EFX_VF_BUFTBL_PER_VI * efx_vf_size(efx);

        vf->pci_rid = devfn;
        snprintf(vf->pci_name, sizeof(vf->pci_name),
             "%04x:%02x:%02x.%d",
             pci_domain_nr(pci_dev->bus), pci_dev->bus->number,
             PCI_SLOT(devfn), PCI_FUNC(devfn));

        rc = efx_nic_alloc_buffer(efx, &vf->buf, EFX_PAGE_SIZE);
        if (rc)
            goto fail;

        devfn += stride;
    }

    return 0;

fail:
    efx_sriov_vfs_fini(efx);
    return rc;
}

int efx_sriov_init(struct efx_nic *efx)
{
    struct net_device *net_dev = efx->net_dev;
    struct vfdi_status *vfdi_status;
    int rc;

    /* Ensure there's room for vf_channel */
    BUILD_BUG_ON(EFX_MAX_CHANNELS + 1 >= EFX_VI_BASE);
    /* Ensure that VI_BASE is aligned on VI_SCALE */
    BUILD_BUG_ON(EFX_VI_BASE & ((1 << EFX_VI_SCALE_MAX) - 1));

    if (efx->vf_count == 0)
        return 0;

    rc = efx_sriov_cmd(efx, true, NULL, NULL);
    if (rc)
        goto fail_cmd;

    rc = efx_nic_alloc_buffer(efx, &efx->vfdi_status, sizeof(*vfdi_status));
    if (rc)
        goto fail_status;
    vfdi_status = efx->vfdi_status.addr;
    memset(vfdi_status, 0, sizeof(*vfdi_status));
    vfdi_status->version = 1;
    vfdi_status->length = sizeof(*vfdi_status);
    vfdi_status->max_tx_channels = vf_max_tx_channels;
    vfdi_status->vi_scale = efx->vi_scale;
    vfdi_status->rss_rxq_count = efx->rss_spread;
    vfdi_status->peer_count = 1 + efx->vf_count;
    vfdi_status->timer_quantum_ns = efx->timer_quantum_ns;

    rc = efx_sriov_vf_alloc(efx);
    if (rc)
        goto fail_alloc;

    mutex_init(&efx->local_lock);
    INIT_WORK(&efx->peer_work, efx_sriov_peer_work);
    INIT_LIST_HEAD(&efx->local_addr_list);
    INIT_LIST_HEAD(&efx->local_page_list);

    rc = efx_sriov_vfs_init(efx);
    if (rc)
        goto fail_vfs;

    rtnl_lock();
    memcpy(vfdi_status->peers[0].mac_addr,
           net_dev->dev_addr, ETH_ALEN);
    efx->vf_init_count = efx->vf_count;
    rtnl_unlock();

    efx_sriov_usrev(efx, true);

    /* At this point we must be ready to accept VFDI requests */

    rc = pci_enable_sriov(efx->pci_dev, efx->vf_count);
    if (rc)
        goto fail_pci;

    netif_info(efx, probe, net_dev,
           "enabled SR-IOV for %d VFs, %d VI per VF\n",
           efx->vf_count, efx_vf_size(efx));
    return 0;

fail_pci:
    efx_sriov_usrev(efx, false);
    rtnl_lock();
    efx->vf_init_count = 0;
    rtnl_unlock();
    efx_sriov_vfs_fini(efx);
fail_vfs:
    cancel_work_sync(&efx->peer_work);
    efx_sriov_free_local(efx);
    kfree(efx->vf);
fail_alloc:
    efx_nic_free_buffer(efx, &efx->vfdi_status);
fail_status:
    efx_sriov_cmd(efx, false, NULL, NULL);
fail_cmd:
    return rc;
}

void efx_sriov_fini(struct efx_nic *efx)
{
    struct efx_vf *vf;
    unsigned int pos;

    if (efx->vf_init_count == 0)
        return;

    /* Disable all interfaces to reconfiguration */
    BUG_ON(efx->vfdi_channel->enabled);
    efx_sriov_usrev(efx, false);
    rtnl_lock();
    efx->vf_init_count = 0;
    rtnl_unlock();

    /* Flush all reconfiguration work */
    for (pos = 0; pos < efx->vf_count; ++pos) {
        vf = efx->vf + pos;
        cancel_work_sync(&vf->req);
        cancel_work_sync(&vf->reset_work);
    }
    cancel_work_sync(&efx->peer_work);

    pci_disable_sriov(efx->pci_dev);

    /* Tear down back-end state */
    efx_sriov_vfs_fini(efx);
    efx_sriov_free_local(efx);
    kfree(efx->vf);
    efx_nic_free_buffer(efx, &efx->vfdi_status);
    efx_sriov_cmd(efx, false, NULL, NULL);
}

void efx_sriov_event(struct efx_channel *channel, efx_qword_t *event)
{
    struct efx_nic *efx = channel->efx;
    struct efx_vf *vf;
    unsigned qid, seq, type, data;

    qid = EFX_QWORD_FIELD(*event, FSF_CZ_USER_QID);

    /* USR_EV_REG_VALUE is dword0, so access the VFDI_EV fields directly */
    BUILD_BUG_ON(FSF_CZ_USER_EV_REG_VALUE_LBN != 0);
    seq = EFX_QWORD_FIELD(*event, VFDI_EV_SEQ);
    type = EFX_QWORD_FIELD(*event, VFDI_EV_TYPE);
    data = EFX_QWORD_FIELD(*event, VFDI_EV_DATA);

    netif_vdbg(efx, hw, efx->net_dev,
           "USR_EV event from qid %d seq 0x%x type %d data 0x%x\n",
           qid, seq, type, data);

    if (map_vi_index(efx, qid, &vf, NULL))
        return;
    if (vf->busy)
        goto error;

    if (type == VFDI_EV_TYPE_REQ_WORD0) {
        /* Resynchronise */
        vf->req_type = VFDI_EV_TYPE_REQ_WORD0;
        vf->req_seqno = seq + 1;
        vf->req_addr = 0;
    } else if (seq != (vf->req_seqno++ & 0xff) || type != vf->req_type)
        goto error;

    switch (vf->req_type) {
    case VFDI_EV_TYPE_REQ_WORD0:
    case VFDI_EV_TYPE_REQ_WORD1:
    case VFDI_EV_TYPE_REQ_WORD2:
        vf->req_addr |= (u64)data << (vf->req_type << 4);
        ++vf->req_type;
        return;

    case VFDI_EV_TYPE_REQ_WORD3:
        vf->req_addr |= (u64)data << 48;
        vf->req_type = VFDI_EV_TYPE_REQ_WORD0;
        vf->busy = true;
        queue_work(vfdi_workqueue, &vf->req);
        return;
    }

error:
    if (net_ratelimit())
        netif_err(efx, hw, efx->net_dev,
              "ERROR: Screaming VFDI request from %s\n",
              vf->pci_name);
    /* Reset the request and sequence number */
    vf->req_type = VFDI_EV_TYPE_REQ_WORD0;
    vf->req_seqno = seq + 1;
}

void efx_sriov_flr(struct efx_nic *efx, unsigned vf_i)
{
    struct efx_vf *vf;

    if (vf_i > efx->vf_init_count)
        return;
    vf = efx->vf + vf_i;
    netif_info(efx, hw, efx->net_dev,
           "FLR on VF %s\n", vf->pci_name);

    vf->status_addr = 0;
    efx_vfdi_remove_all_filters(vf);
    efx_vfdi_flush_clear(vf);

    vf->evq0_count = 0;
}

void efx_sriov_mac_address_changed(struct efx_nic *efx)
{
    struct vfdi_status *vfdi_status = efx->vfdi_status.addr;

    if (!efx->vf_init_count)
        return;
    memcpy(vfdi_status->peers[0].mac_addr,
           efx->net_dev->dev_addr, ETH_ALEN);
    queue_work(vfdi_workqueue, &efx->peer_work);
}

void efx_sriov_tx_flush_done(struct efx_nic *efx, efx_qword_t *event)
{
    struct efx_vf *vf;
    unsigned queue, qid;

    queue = EFX_QWORD_FIELD(*event,  FSF_AZ_DRIVER_EV_SUBDATA);
    if (map_vi_index(efx, queue, &vf, &qid))
        return;
    /* Ignore flush completions triggered by an FLR */
    if (!test_bit(qid, vf->txq_mask))
        return;

    __clear_bit(qid, vf->txq_mask);
    --vf->txq_count;

    if (efx_vfdi_flush_wake(vf))
        wake_up(&vf->flush_waitq);
}

void efx_sriov_rx_flush_done(struct efx_nic *efx, efx_qword_t *event)
{
    struct efx_vf *vf;
    unsigned ev_failed, queue, qid;

    queue = EFX_QWORD_FIELD(*event, FSF_AZ_DRIVER_EV_RX_DESCQ_ID);
    ev_failed = EFX_QWORD_FIELD(*event,
                    FSF_AZ_DRIVER_EV_RX_FLUSH_FAIL);
    if (map_vi_index(efx, queue, &vf, &qid))
        return;
    if (!test_bit(qid, vf->rxq_mask))
        return;

    if (ev_failed) {
        set_bit(qid, vf->rxq_retry_mask);
        atomic_inc(&vf->rxq_retry_count);
    } else {
        __clear_bit(qid, vf->rxq_mask);
        --vf->rxq_count;
    }
    if (efx_vfdi_flush_wake(vf))
        wake_up(&vf->flush_waitq);
}

/* Called from napi. Schedule the reset work item */
void efx_sriov_desc_fetch_err(struct efx_nic *efx, unsigned dmaq)
{
    struct efx_vf *vf;
    unsigned int rel;

    if (map_vi_index(efx, dmaq, &vf, &rel))
        return;

    if (net_ratelimit())
        netif_err(efx, hw, efx->net_dev,
              "VF %d DMA Q %d reports descriptor fetch error.\n",
              vf->index, rel);
    queue_work(vfdi_workqueue, &vf->reset_work);
}

/* Reset all VFs */
void efx_sriov_reset(struct efx_nic *efx)
{
    unsigned int vf_i;
    struct efx_buffer buf;
    struct efx_vf *vf;

    ASSERT_RTNL();

    if (efx->vf_init_count == 0)
        return;

    efx_sriov_usrev(efx, true);
    (void)efx_sriov_cmd(efx, true, NULL, NULL);

    if (efx_nic_alloc_buffer(efx, &buf, EFX_PAGE_SIZE))
        return;

    for (vf_i = 0; vf_i < efx->vf_init_count; ++vf_i) {
        vf = efx->vf + vf_i;
        efx_sriov_reset_vf(vf, &buf);
    }

    efx_nic_free_buffer(efx, &buf);
}

int efx_init_sriov(void)
{
    /* A single threaded workqueue is sufficient. efx_sriov_vfdi() and
     * efx_sriov_peer_work() spend almost all their time sleeping for
     * MCDI to complete anyway
     */
    vfdi_workqueue = create_singlethread_workqueue("sfc_vfdi");
    if (!vfdi_workqueue)
        return -ENOMEM;

    return 0;
}

void efx_fini_sriov(void)
{
    destroy_workqueue(vfdi_workqueue);
}

int efx_sriov_set_vf_mac(struct net_device *net_dev, int vf_i, u8 *mac)
{
    struct efx_nic *efx = netdev_priv(net_dev);
    struct efx_vf *vf;

    if (vf_i >= efx->vf_init_count)
        return -EINVAL;
    vf = efx->vf + vf_i;

    mutex_lock(&vf->status_lock);
    memcpy(vf->addr.mac_addr, mac, ETH_ALEN);
    __efx_sriov_update_vf_addr(vf);
    mutex_unlock(&vf->status_lock);

    return 0;
}

int efx_sriov_set_vf_vlan(struct net_device *net_dev, int vf_i,
              u16 vlan, u8 qos)
{
    struct efx_nic *efx = netdev_priv(net_dev);
    struct efx_vf *vf;
    u16 tci;

    if (vf_i >= efx->vf_init_count)
        return -EINVAL;
    vf = efx->vf + vf_i;

    mutex_lock(&vf->status_lock);
    tci = (vlan & VLAN_VID_MASK) | ((qos & 0x7) << VLAN_PRIO_SHIFT);
    vf->addr.tci = htons(tci);
    __efx_sriov_update_vf_addr(vf);
    mutex_unlock(&vf->status_lock);

    return 0;
}

int efx_sriov_set_vf_spoofchk(struct net_device *net_dev, int vf_i,
                  bool spoofchk)
{
    struct efx_nic *efx = netdev_priv(net_dev);
    struct efx_vf *vf;
    int rc;

    if (vf_i >= efx->vf_init_count)
        return -EINVAL;
    vf = efx->vf + vf_i;

    mutex_lock(&vf->txq_lock);
    if (vf->txq_count == 0) {
        vf->tx_filter_mode =
            spoofchk ? VF_TX_FILTER_ON : VF_TX_FILTER_OFF;
        rc = 0;
    } else {
        /* This cannot be changed while TX queues are running */
        rc = -EBUSY;
    }
    mutex_unlock(&vf->txq_lock);
    return rc;
}

int efx_sriov_get_vf_config(struct net_device *net_dev, int vf_i,
                struct ifla_vf_info *ivi)
{
    struct efx_nic *efx = netdev_priv(net_dev);
    struct efx_vf *vf;
    u16 tci;

    if (vf_i >= efx->vf_init_count)
        return -EINVAL;
    vf = efx->vf + vf_i;

    ivi->vf = vf_i;
    memcpy(ivi->mac, vf->addr.mac_addr, ETH_ALEN);
    ivi->tx_rate = 0;
    tci = ntohs(vf->addr.tci);
    ivi->vlan = tci & VLAN_VID_MASK;
    ivi->qos = (tci >> VLAN_PRIO_SHIFT) & 0x7;
    ivi->spoofchk = vf->tx_filter_mode == VF_TX_FILTER_ON;

    return 0;
}