/*******************************************************************************

  Intel 82599 Virtual Function driver
  Copyright(c) 1999 - 2012 Intel Corporation.

  This program is free software; you can redistribute it and/or modify it
  under the terms and conditions of the GNU General Public License,
  version 2, as published by the Free Software Foundation.

  This program is distributed in the hope it will be useful, but WITHOUT
  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  more details.

  You should have received a copy of the GNU General Public License along with
  this program; if not, write to the Free Software Foundation, Inc.,
  51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.

  The full GNU General Public License is included in this distribution in
  the file called "COPYING".

  Contact Information:
  e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
  Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497

*******************************************************************************/


/******************************************************************************
 Copyright (c)2006 - 2007 Myricom, Inc. for some LRO specific code
******************************************************************************/

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/types.h>
#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/netdevice.h>
#include <linux/vmalloc.h>
#include <linux/string.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#include <linux/sctp.h>
#include <linux/ipv6.h>
#include <linux/slab.h>
#include <net/checksum.h>
#include <net/ip6_checksum.h>
#include <linux/ethtool.h>
#include <linux/if.h>
#include <linux/if_vlan.h>
#include <linux/prefetch.h>

#include "ixgbevf.h"

const char ixgbevf_driver_name[] = "ixgbevf";
static const char ixgbevf_driver_string[] =
        "Intel(R) 10 Gigabit PCI Express Virtual Function Network Driver";

#define DRV_VERSION "2.7.12-k"
const char ixgbevf_driver_version[] = DRV_VERSION;
static char ixgbevf_copyright[] =
        "Copyright (c) 2009 - 2012 Intel Corporation.";

static const struct ixgbevf_info *ixgbevf_info_tbl[] = {
        [board_82599_vf] = &ixgbevf_82599_vf_info,
        [board_X540_vf]  = &ixgbevf_X540_vf_info,
};

/* ixgbevf_pci_tbl - PCI Device ID Table
 *
 * Wildcard entries (PCI_ANY_ID) should come last
 * Last entry must be all 0s
 *
 * { Vendor ID, Device ID, SubVendor ID, SubDevice ID,
 *   Class, Class Mask, private data (not used) }
 */
static DEFINE_PCI_DEVICE_TABLE(ixgbevf_pci_tbl) = {
        {PCI_VDEVICE(INTEL, IXGBE_DEV_ID_82599_VF), board_82599_vf },
        {PCI_VDEVICE(INTEL, IXGBE_DEV_ID_X540_VF), board_X540_vf },
        /* required last entry */
        {0, }
};
MODULE_DEVICE_TABLE(pci, ixgbevf_pci_tbl);

MODULE_AUTHOR("Intel Corporation, <linux.nics@intel.com>");
MODULE_DESCRIPTION("Intel(R) 82599 Virtual Function Driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);

#define DEFAULT_MSG_ENABLE (NETIF_MSG_DRV|NETIF_MSG_PROBE|NETIF_MSG_LINK)
static int debug = -1;
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");

/* forward decls */
static void ixgbevf_set_itr(struct ixgbevf_q_vector *q_vector);
static void ixgbevf_free_all_rx_resources(struct ixgbevf_adapter *adapter);

static inline void ixgbevf_release_rx_desc(struct ixgbe_hw *hw,
                                           struct ixgbevf_ring *rx_ring,
                                           u32 val)
{
        /*
         * Force memory writes to complete before letting h/w
         * know there are new descriptors to fetch.  (Only
         * applicable for weak-ordered memory model archs,
         * such as IA-64).
         */
        wmb();
        IXGBE_WRITE_REG(hw, IXGBE_VFRDT(rx_ring->reg_idx), val);
}

/**
 * ixgbevf_set_ivar - set IVAR registers - maps interrupt causes to vectors
 * @adapter: pointer to adapter struct
 * @direction: 0 for Rx, 1 for Tx, -1 for other causes
 * @queue: queue to map the corresponding interrupt to
 * @msix_vector: the vector to map to the corresponding queue
 */
static void ixgbevf_set_ivar(struct ixgbevf_adapter *adapter, s8 direction,
                             u8 queue, u8 msix_vector)
{
        u32 ivar, index;
        struct ixgbe_hw *hw = &adapter->hw;
        if (direction == -1) {
                /* other causes */
                msix_vector |= IXGBE_IVAR_ALLOC_VAL;
                ivar = IXGBE_READ_REG(hw, IXGBE_VTIVAR_MISC);
                ivar &= ~0xFF;
                ivar |= msix_vector;
                IXGBE_WRITE_REG(hw, IXGBE_VTIVAR_MISC, ivar);
        } else {
                /* tx or rx causes */
                msix_vector |= IXGBE_IVAR_ALLOC_VAL;
                index = ((16 * (queue & 1)) + (8 * direction));
                ivar = IXGBE_READ_REG(hw, IXGBE_VTIVAR(queue >> 1));
                ivar &= ~(0xFF << index);
                ivar |= (msix_vector << index);
                IXGBE_WRITE_REG(hw, IXGBE_VTIVAR(queue >> 1), ivar);
        }
}

static void ixgbevf_unmap_and_free_tx_resource(struct ixgbevf_ring *tx_ring,
                                               struct ixgbevf_tx_buffer
                                               *tx_buffer_info)
{
        if (tx_buffer_info->dma) {
                if (tx_buffer_info->mapped_as_page)
                        dma_unmap_page(tx_ring->dev,
                                       tx_buffer_info->dma,
                                       tx_buffer_info->length,
                                       DMA_TO_DEVICE);
                else
                        dma_unmap_single(tx_ring->dev,
                                         tx_buffer_info->dma,
                                         tx_buffer_info->length,
                                         DMA_TO_DEVICE);
                tx_buffer_info->dma = 0;
        }
        if (tx_buffer_info->skb) {
                dev_kfree_skb_any(tx_buffer_info->skb);
                tx_buffer_info->skb = NULL;
        }
        tx_buffer_info->time_stamp = 0;
        /* tx_buffer_info must be completely set up in the transmit path */
}

#define IXGBE_MAX_TXD_PWR       14
#define IXGBE_MAX_DATA_PER_TXD  (1 << IXGBE_MAX_TXD_PWR)

/* Tx Descriptors needed, worst case */
#define TXD_USE_COUNT(S) DIV_ROUND_UP((S), IXGBE_MAX_DATA_PER_TXD)
#define DESC_NEEDED (MAX_SKB_FRAGS + 4)

static void ixgbevf_tx_timeout(struct net_device *netdev);

/**
 * ixgbevf_clean_tx_irq - Reclaim resources after transmit completes
 * @q_vector: board private structure
 * @tx_ring: tx ring to clean
 **/
static bool ixgbevf_clean_tx_irq(struct ixgbevf_q_vector *q_vector,
                                 struct ixgbevf_ring *tx_ring)
{
        struct ixgbevf_adapter *adapter = q_vector->adapter;
        union ixgbe_adv_tx_desc *tx_desc, *eop_desc;
        struct ixgbevf_tx_buffer *tx_buffer_info;
        unsigned int i, count = 0;
        unsigned int total_bytes = 0, total_packets = 0;

        if (test_bit(__IXGBEVF_DOWN, &adapter->state))
                return true;

        i = tx_ring->next_to_clean;
        tx_buffer_info = &tx_ring->tx_buffer_info[i];
        eop_desc = tx_buffer_info->next_to_watch;

        do {
                bool cleaned = false;

                /* if next_to_watch is not set then there is no work pending */
                if (!eop_desc)
                        break;

                /* prevent any other reads prior to eop_desc */
                read_barrier_depends();

                /* if DD is not set pending work has not been completed */
                if (!(eop_desc->wb.status & cpu_to_le32(IXGBE_TXD_STAT_DD)))
                        break;

                /* clear next_to_watch to prevent false hangs */
                tx_buffer_info->next_to_watch = NULL;

                for ( ; !cleaned; count++) {
                        struct sk_buff *skb;
                        tx_desc = IXGBEVF_TX_DESC(tx_ring, i);
                        cleaned = (tx_desc == eop_desc);
                        skb = tx_buffer_info->skb;

                        if (cleaned && skb) {
                                unsigned int segs, bytecount;

                                /* gso_segs is currently only valid for tcp */
                                segs = skb_shinfo(skb)->gso_segs ?: 1;
                                /* multiply data chunks by size of headers */
                                bytecount = ((segs - 1) * skb_headlen(skb)) +
                                            skb->len;
                                total_packets += segs;
                                total_bytes += bytecount;
                        }

                        ixgbevf_unmap_and_free_tx_resource(tx_ring,
                                                           tx_buffer_info);

                        tx_desc->wb.status = 0;

                        i++;
                        if (i == tx_ring->count)
                                i = 0;

                        tx_buffer_info = &tx_ring->tx_buffer_info[i];
                }

                eop_desc = tx_buffer_info->next_to_watch;
        } while (count < tx_ring->count);

        tx_ring->next_to_clean = i;

#define TX_WAKE_THRESHOLD (DESC_NEEDED * 2)
        if (unlikely(count && netif_carrier_ok(tx_ring->netdev) &&
                     (IXGBE_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
                /* Make sure that anybody stopping the queue after this
                 * sees the new next_to_clean.
                 */
                smp_mb();
                if (__netif_subqueue_stopped(tx_ring->netdev,
                                             tx_ring->queue_index) &&
                    !test_bit(__IXGBEVF_DOWN, &adapter->state)) {
                        netif_wake_subqueue(tx_ring->netdev,
                                            tx_ring->queue_index);
                        ++adapter->restart_queue;
                }
        }

        u64_stats_update_begin(&tx_ring->syncp);
        tx_ring->total_bytes += total_bytes;
        tx_ring->total_packets += total_packets;
        u64_stats_update_end(&tx_ring->syncp);
        q_vector->tx.total_bytes += total_bytes;
        q_vector->tx.total_packets += total_packets;

        return count < tx_ring->count;
}

/**
 * ixgbevf_receive_skb - Send a completed packet up the stack
 * @q_vector: structure containing interrupt and ring information
 * @skb: packet to send up
 * @status: hardware indication of status of receive
 * @rx_desc: rx descriptor
 **/
static void ixgbevf_receive_skb(struct ixgbevf_q_vector *q_vector,
                                struct sk_buff *skb, u8 status,
                                union ixgbe_adv_rx_desc *rx_desc)
{
        struct ixgbevf_adapter *adapter = q_vector->adapter;
        bool is_vlan = (status & IXGBE_RXD_STAT_VP);
        u16 tag = le16_to_cpu(rx_desc->wb.upper.vlan);

        if (is_vlan && test_bit(tag & VLAN_VID_MASK, adapter->active_vlans))
                __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), tag);

        if (!(adapter->flags & IXGBE_FLAG_IN_NETPOLL))
                napi_gro_receive(&q_vector->napi, skb);
        else
                netif_rx(skb);
}

/**
 * ixgbevf_rx_checksum - indicate in skb if hw indicated a good cksum
 * @ring: pointer to Rx descriptor ring structure
 * @status_err: hardware indication of status of receive
 * @skb: skb currently being received and modified
 **/
static inline void ixgbevf_rx_checksum(struct ixgbevf_ring *ring,
                                       u32 status_err, struct sk_buff *skb)
{
        skb_checksum_none_assert(skb);

        /* Rx csum disabled */
        if (!(ring->netdev->features & NETIF_F_RXCSUM))
                return;

        /* if IP and error */
        if ((status_err & IXGBE_RXD_STAT_IPCS) &&
            (status_err & IXGBE_RXDADV_ERR_IPE)) {
                ring->hw_csum_rx_error++;
                return;
        }

        if (!(status_err & IXGBE_RXD_STAT_L4CS))
                return;

        if (status_err & IXGBE_RXDADV_ERR_TCPE) {
                ring->hw_csum_rx_error++;
                return;
        }

        /* It must be a TCP or UDP packet with a valid checksum */
        skb->ip_summed = CHECKSUM_UNNECESSARY;
        ring->hw_csum_rx_good++;
}

/**
 * ixgbevf_alloc_rx_buffers - Replace used receive buffers; packet split
 * @adapter: address of board private structure
 **/
static void ixgbevf_alloc_rx_buffers(struct ixgbevf_adapter *adapter,
                                     struct ixgbevf_ring *rx_ring,
                                     int cleaned_count)
{
        struct pci_dev *pdev = adapter->pdev;
        union ixgbe_adv_rx_desc *rx_desc;
        struct ixgbevf_rx_buffer *bi;
        unsigned int i = rx_ring->next_to_use;

        bi = &rx_ring->rx_buffer_info[i];

        while (cleaned_count--) {
                rx_desc = IXGBEVF_RX_DESC(rx_ring, i);

                if (!bi->skb) {
                        struct sk_buff *skb;

                        skb = netdev_alloc_skb_ip_align(rx_ring->netdev,
                                                        rx_ring->rx_buf_len);
                        if (!skb) {
                                adapter->alloc_rx_buff_failed++;
                                goto no_buffers;
                        }
                        bi->skb = skb;

                        bi->dma = dma_map_single(&pdev->dev, skb->data,
                                                 rx_ring->rx_buf_len,
                                                 DMA_FROM_DEVICE);
                        if (dma_mapping_error(&pdev->dev, bi->dma)) {
                                dev_kfree_skb(skb);
                                bi->skb = NULL;
                                dev_err(&pdev->dev, "RX DMA map failed\n");
                                break;
                        }
                }
                rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);

                i++;
                if (i == rx_ring->count)
                        i = 0;
                bi = &rx_ring->rx_buffer_info[i];
        }

no_buffers:
        if (rx_ring->next_to_use != i) {
                rx_ring->next_to_use = i;
                ixgbevf_release_rx_desc(&adapter->hw, rx_ring, i);
        }
}

static inline void ixgbevf_irq_enable_queues(struct ixgbevf_adapter *adapter,
                                             u32 qmask)
{
        struct ixgbe_hw *hw = &adapter->hw;

        IXGBE_WRITE_REG(hw, IXGBE_VTEIMS, qmask);
}

static bool ixgbevf_clean_rx_irq(struct ixgbevf_q_vector *q_vector,
                                 struct ixgbevf_ring *rx_ring,
                                 int budget)
{
        struct ixgbevf_adapter *adapter = q_vector->adapter;
        struct pci_dev *pdev = adapter->pdev;
        union ixgbe_adv_rx_desc *rx_desc, *next_rxd;
        struct ixgbevf_rx_buffer *rx_buffer_info, *next_buffer;
        struct sk_buff *skb;
        unsigned int i;
        u32 len, staterr;
        int cleaned_count = 0;
        unsigned int total_rx_bytes = 0, total_rx_packets = 0;

        i = rx_ring->next_to_clean;
        rx_desc = IXGBEVF_RX_DESC(rx_ring, i);
        staterr = le32_to_cpu(rx_desc->wb.upper.status_error);
        rx_buffer_info = &rx_ring->rx_buffer_info[i];

        while (staterr & IXGBE_RXD_STAT_DD) {
                if (!budget)
                        break;
                budget--;

                rmb(); /* read descriptor and rx_buffer_info after status DD */
                len = le16_to_cpu(rx_desc->wb.upper.length);
                skb = rx_buffer_info->skb;
                prefetch(skb->data - NET_IP_ALIGN);
                rx_buffer_info->skb = NULL;

                if (rx_buffer_info->dma) {
                        dma_unmap_single(&pdev->dev, rx_buffer_info->dma,
                                         rx_ring->rx_buf_len,
                                         DMA_FROM_DEVICE);
                        rx_buffer_info->dma = 0;
                        skb_put(skb, len);
                }

                i++;
                if (i == rx_ring->count)
                        i = 0;

                next_rxd = IXGBEVF_RX_DESC(rx_ring, i);
                prefetch(next_rxd);
                cleaned_count++;

                next_buffer = &rx_ring->rx_buffer_info[i];

                if (!(staterr & IXGBE_RXD_STAT_EOP)) {
                        skb->next = next_buffer->skb;
                        IXGBE_CB(skb->next)->prev = skb;
                        adapter->non_eop_descs++;
                        goto next_desc;
                }

                /* we should not be chaining buffers, if we did drop the skb */
                if (IXGBE_CB(skb)->prev) {
                        do {
                                struct sk_buff *this = skb;
                                skb = IXGBE_CB(skb)->prev;
                                dev_kfree_skb(this);
                        } while (skb);
                        goto next_desc;
                }

                /* ERR_MASK will only have valid bits if EOP set */
                if (unlikely(staterr & IXGBE_RXDADV_ERR_FRAME_ERR_MASK)) {
                        dev_kfree_skb_irq(skb);
                        goto next_desc;
                }

                ixgbevf_rx_checksum(rx_ring, staterr, skb);

                /* probably a little skewed due to removing CRC */
                total_rx_bytes += skb->len;
                total_rx_packets++;

                /*
                 * Work around issue of some types of VM to VM loop back
                 * packets not getting split correctly
                 */
                if (staterr & IXGBE_RXD_STAT_LB) {
                        u32 header_fixup_len = skb_headlen(skb);
                        if (header_fixup_len < 14)
                                skb_push(skb, header_fixup_len);
                }
                skb->protocol = eth_type_trans(skb, rx_ring->netdev);

                /* Workaround hardware that can't do proper VEPA multicast
                 * source pruning.
                 */
                if ((skb->pkt_type & (PACKET_BROADCAST | PACKET_MULTICAST)) &&
                    !(compare_ether_addr(adapter->netdev->dev_addr,
                                        eth_hdr(skb)->h_source))) {
                        dev_kfree_skb_irq(skb);
                        goto next_desc;
                }

                ixgbevf_receive_skb(q_vector, skb, staterr, rx_desc);

next_desc:
                rx_desc->wb.upper.status_error = 0;

                /* return some buffers to hardware, one at a time is too slow */
                if (cleaned_count >= IXGBEVF_RX_BUFFER_WRITE) {
                        ixgbevf_alloc_rx_buffers(adapter, rx_ring,
                                                 cleaned_count);
                        cleaned_count = 0;
                }

                /* use prefetched values */
                rx_desc = next_rxd;
                rx_buffer_info = &rx_ring->rx_buffer_info[i];

                staterr = le32_to_cpu(rx_desc->wb.upper.status_error);
        }

        rx_ring->next_to_clean = i;
        cleaned_count = IXGBE_DESC_UNUSED(rx_ring);

        if (cleaned_count)
                ixgbevf_alloc_rx_buffers(adapter, rx_ring, cleaned_count);

        u64_stats_update_begin(&rx_ring->syncp);
        rx_ring->total_packets += total_rx_packets;
        rx_ring->total_bytes += total_rx_bytes;
        u64_stats_update_end(&rx_ring->syncp);
        q_vector->rx.total_packets += total_rx_packets;
        q_vector->rx.total_bytes += total_rx_bytes;

        return !!budget;
}

/**
 * ixgbevf_poll - NAPI polling calback
 * @napi: napi struct with our devices info in it
 * @budget: amount of work driver is allowed to do this pass, in packets
 *
 * This function will clean more than one or more rings associated with a
 * q_vector.
 **/
static int ixgbevf_poll(struct napi_struct *napi, int budget)
{
        struct ixgbevf_q_vector *q_vector =
                container_of(napi, struct ixgbevf_q_vector, napi);
        struct ixgbevf_adapter *adapter = q_vector->adapter;
        struct ixgbevf_ring *ring;
        int per_ring_budget;
        bool clean_complete = true;

        ixgbevf_for_each_ring(ring, q_vector->tx)
                clean_complete &= ixgbevf_clean_tx_irq(q_vector, ring);

        /* attempt to distribute budget to each queue fairly, but don't allow
         * the budget to go below 1 because we'll exit polling */
        if (q_vector->rx.count > 1)
                per_ring_budget = max(budget/q_vector->rx.count, 1);
        else
                per_ring_budget = budget;

        adapter->flags |= IXGBE_FLAG_IN_NETPOLL;
        ixgbevf_for_each_ring(ring, q_vector->rx)
                clean_complete &= ixgbevf_clean_rx_irq(q_vector, ring,
                                                       per_ring_budget);
        adapter->flags &= ~IXGBE_FLAG_IN_NETPOLL;

        /* If all work not completed, return budget and keep polling */
        if (!clean_complete)
                return budget;
        /* all work done, exit the polling mode */
        napi_complete(napi);
        if (adapter->rx_itr_setting & 1)
                ixgbevf_set_itr(q_vector);
        if (!test_bit(__IXGBEVF_DOWN, &adapter->state))
                ixgbevf_irq_enable_queues(adapter,
                                          1 << q_vector->v_idx);

        return 0;
}

/**
 * ixgbevf_write_eitr - write VTEITR register in hardware specific way
 * @q_vector: structure containing interrupt and ring information
 */
static void ixgbevf_write_eitr(struct ixgbevf_q_vector *q_vector)
{
        struct ixgbevf_adapter *adapter = q_vector->adapter;
        struct ixgbe_hw *hw = &adapter->hw;
        int v_idx = q_vector->v_idx;
        u32 itr_reg = q_vector->itr & IXGBE_MAX_EITR;

        /*
         * set the WDIS bit to not clear the timer bits and cause an
         * immediate assertion of the interrupt
         */
        itr_reg |= IXGBE_EITR_CNT_WDIS;

        IXGBE_WRITE_REG(hw, IXGBE_VTEITR(v_idx), itr_reg);
}

/**
 * ixgbevf_configure_msix - Configure MSI-X hardware
 * @adapter: board private structure
 *
 * ixgbevf_configure_msix sets up the hardware to properly generate MSI-X
 * interrupts.
 **/
static void ixgbevf_configure_msix(struct ixgbevf_adapter *adapter)
{
        struct ixgbevf_q_vector *q_vector;
        int q_vectors, v_idx;

        q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;
        adapter->eims_enable_mask = 0;

        /*
         * Populate the IVAR table and set the ITR values to the
         * corresponding register.
         */
        for (v_idx = 0; v_idx < q_vectors; v_idx++) {
                struct ixgbevf_ring *ring;
                q_vector = adapter->q_vector[v_idx];

                ixgbevf_for_each_ring(ring, q_vector->rx)
                        ixgbevf_set_ivar(adapter, 0, ring->reg_idx, v_idx);

                ixgbevf_for_each_ring(ring, q_vector->tx)
                        ixgbevf_set_ivar(adapter, 1, ring->reg_idx, v_idx);

                if (q_vector->tx.ring && !q_vector->rx.ring) {
                        /* tx only vector */
                        if (adapter->tx_itr_setting == 1)
                                q_vector->itr = IXGBE_10K_ITR;
                        else
                                q_vector->itr = adapter->tx_itr_setting;
                } else {
                        /* rx or rx/tx vector */
                        if (adapter->rx_itr_setting == 1)
                                q_vector->itr = IXGBE_20K_ITR;
                        else
                                q_vector->itr = adapter->rx_itr_setting;
                }

                /* add q_vector eims value to global eims_enable_mask */
                adapter->eims_enable_mask |= 1 << v_idx;

                ixgbevf_write_eitr(q_vector);
        }

        ixgbevf_set_ivar(adapter, -1, 1, v_idx);
        /* setup eims_other and add value to global eims_enable_mask */
        adapter->eims_other = 1 << v_idx;
        adapter->eims_enable_mask |= adapter->eims_other;
}

enum latency_range {
        lowest_latency = 0,
        low_latency = 1,
        bulk_latency = 2,
        latency_invalid = 255
};

/**
 * ixgbevf_update_itr - update the dynamic ITR value based on statistics
 * @q_vector: structure containing interrupt and ring information
 * @ring_container: structure containing ring performance data
 *
 *      Stores a new ITR value based on packets and byte
 *      counts during the last interrupt.  The advantage of per interrupt
 *      computation is faster updates and more accurate ITR for the current
 *      traffic pattern.  Constants in this function were computed
 *      based on theoretical maximum wire speed and thresholds were set based
 *      on testing data as well as attempting to minimize response time
 *      while increasing bulk throughput.
 **/
static void ixgbevf_update_itr(struct ixgbevf_q_vector *q_vector,
                               struct ixgbevf_ring_container *ring_container)
{
        int bytes = ring_container->total_bytes;
        int packets = ring_container->total_packets;
        u32 timepassed_us;
        u64 bytes_perint;
        u8 itr_setting = ring_container->itr;

        if (packets == 0)
                return;

        /* simple throttlerate management
         *    0-20MB/s lowest (100000 ints/s)
         *   20-100MB/s low   (20000 ints/s)
         *  100-1249MB/s bulk (8000 ints/s)
         */
        /* what was last interrupt timeslice? */
        timepassed_us = q_vector->itr >> 2;
        bytes_perint = bytes / timepassed_us; /* bytes/usec */

        switch (itr_setting) {
        case lowest_latency:
                if (bytes_perint > 10)
                        itr_setting = low_latency;
                break;
        case low_latency:
                if (bytes_perint > 20)
                        itr_setting = bulk_latency;
                else if (bytes_perint <= 10)
                        itr_setting = lowest_latency;
                break;
        case bulk_latency:
                if (bytes_perint <= 20)
                        itr_setting = low_latency;
                break;
        }

        /* clear work counters since we have the values we need */
        ring_container->total_bytes = 0;
        ring_container->total_packets = 0;

        /* write updated itr to ring container */
        ring_container->itr = itr_setting;
}

static void ixgbevf_set_itr(struct ixgbevf_q_vector *q_vector)
{
        u32 new_itr = q_vector->itr;
        u8 current_itr;

        ixgbevf_update_itr(q_vector, &q_vector->tx);
        ixgbevf_update_itr(q_vector, &q_vector->rx);

        current_itr = max(q_vector->rx.itr, q_vector->tx.itr);

        switch (current_itr) {
        /* counts and packets in update_itr are dependent on these numbers */
        case lowest_latency:
                new_itr = IXGBE_100K_ITR;
                break;
        case low_latency:
                new_itr = IXGBE_20K_ITR;
                break;
        case bulk_latency:
        default:
                new_itr = IXGBE_8K_ITR;
                break;
        }

        if (new_itr != q_vector->itr) {
                /* do an exponential smoothing */
                new_itr = (10 * new_itr * q_vector->itr) /
                          ((9 * new_itr) + q_vector->itr);

                /* save the algorithm value here */
                q_vector->itr = new_itr;

                ixgbevf_write_eitr(q_vector);
        }
}

static irqreturn_t ixgbevf_msix_other(int irq, void *data)
{
        struct ixgbevf_adapter *adapter = data;
        struct pci_dev *pdev = adapter->pdev;
        struct ixgbe_hw *hw = &adapter->hw;
        u32 msg;
        bool got_ack = false;

        hw->mac.get_link_status = 1;
        if (!hw->mbx.ops.check_for_ack(hw))
                got_ack = true;

        if (!hw->mbx.ops.check_for_msg(hw)) {
                hw->mbx.ops.read(hw, &msg, 1);

                if ((msg & IXGBE_MBVFICR_VFREQ_MASK) == IXGBE_PF_CONTROL_MSG) {
                        mod_timer(&adapter->watchdog_timer,
                                  round_jiffies(jiffies + 1));
                        adapter->link_up = false;
                }

                if (msg & IXGBE_VT_MSGTYPE_NACK)
                        dev_info(&pdev->dev,
                                 "Last Request of type %2.2x to PF Nacked\n",
                                 msg & 0xFF);
                hw->mbx.v2p_mailbox |= IXGBE_VFMAILBOX_PFSTS;
        }

        /* checking for the ack clears the PFACK bit.  Place
         * it back in the v2p_mailbox cache so that anyone
         * polling for an ack will not miss it
         */
        if (got_ack)
                hw->mbx.v2p_mailbox |= IXGBE_VFMAILBOX_PFACK;

        IXGBE_WRITE_REG(hw, IXGBE_VTEIMS, adapter->eims_other);

        return IRQ_HANDLED;
}

/**
 * ixgbevf_msix_clean_rings - single unshared vector rx clean (all queues)
 * @irq: unused
 * @data: pointer to our q_vector struct for this interrupt vector
 **/
static irqreturn_t ixgbevf_msix_clean_rings(int irq, void *data)
{
        struct ixgbevf_q_vector *q_vector = data;

        /* EIAM disabled interrupts (on this vector) for us */
        if (q_vector->rx.ring || q_vector->tx.ring)
                napi_schedule(&q_vector->napi);

        return IRQ_HANDLED;
}

static inline void map_vector_to_rxq(struct ixgbevf_adapter *a, int v_idx,
                                     int r_idx)
{
        struct ixgbevf_q_vector *q_vector = a->q_vector[v_idx];

        a->rx_ring[r_idx].next = q_vector->rx.ring;
        q_vector->rx.ring = &a->rx_ring[r_idx];
        q_vector->rx.count++;
}

static inline void map_vector_to_txq(struct ixgbevf_adapter *a, int v_idx,
                                     int t_idx)
{
        struct ixgbevf_q_vector *q_vector = a->q_vector[v_idx];

        a->tx_ring[t_idx].next = q_vector->tx.ring;
        q_vector->tx.ring = &a->tx_ring[t_idx];
        q_vector->tx.count++;
}

/**
 * ixgbevf_map_rings_to_vectors - Maps descriptor rings to vectors
 * @adapter: board private structure to initialize
 *
 * This function maps descriptor rings to the queue-specific vectors
 * we were allotted through the MSI-X enabling code.  Ideally, we'd have
 * one vector per ring/queue, but on a constrained vector budget, we
 * group the rings as "efficiently" as possible.  You would add new
 * mapping configurations in here.
 **/
static int ixgbevf_map_rings_to_vectors(struct ixgbevf_adapter *adapter)
{
        int q_vectors;
        int v_start = 0;
        int rxr_idx = 0, txr_idx = 0;
        int rxr_remaining = adapter->num_rx_queues;
        int txr_remaining = adapter->num_tx_queues;
        int i, j;
        int rqpv, tqpv;
        int err = 0;

        q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;

        /*
         * The ideal configuration...
         * We have enough vectors to map one per queue.
         */
        if (q_vectors == adapter->num_rx_queues + adapter->num_tx_queues) {
                for (; rxr_idx < rxr_remaining; v_start++, rxr_idx++)
                        map_vector_to_rxq(adapter, v_start, rxr_idx);

                for (; txr_idx < txr_remaining; v_start++, txr_idx++)
                        map_vector_to_txq(adapter, v_start, txr_idx);
                goto out;
        }

        /*
         * If we don't have enough vectors for a 1-to-1
         * mapping, we'll have to group them so there are
         * multiple queues per vector.
         */
        /* Re-adjusting *qpv takes care of the remainder. */
        for (i = v_start; i < q_vectors; i++) {
                rqpv = DIV_ROUND_UP(rxr_remaining, q_vectors - i);
                for (j = 0; j < rqpv; j++) {
                        map_vector_to_rxq(adapter, i, rxr_idx);
                        rxr_idx++;
                        rxr_remaining--;
                }
        }
        for (i = v_start; i < q_vectors; i++) {
                tqpv = DIV_ROUND_UP(txr_remaining, q_vectors - i);
                for (j = 0; j < tqpv; j++) {
                        map_vector_to_txq(adapter, i, txr_idx);
                        txr_idx++;
                        txr_remaining--;
                }
        }

out:
        return err;
}

/**
 * ixgbevf_request_msix_irqs - Initialize MSI-X interrupts
 * @adapter: board private structure
 *
 * ixgbevf_request_msix_irqs allocates MSI-X vectors and requests
 * interrupts from the kernel.
 **/
static int ixgbevf_request_msix_irqs(struct ixgbevf_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        int q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;
        int vector, err;
        int ri = 0, ti = 0;

        for (vector = 0; vector < q_vectors; vector++) {
                struct ixgbevf_q_vector *q_vector = adapter->q_vector[vector];
                struct msix_entry *entry = &adapter->msix_entries[vector];

                if (q_vector->tx.ring && q_vector->rx.ring) {
                        snprintf(q_vector->name, sizeof(q_vector->name) - 1,
                                 "%s-%s-%d", netdev->name, "TxRx", ri++);
                        ti++;
                } else if (q_vector->rx.ring) {
                        snprintf(q_vector->name, sizeof(q_vector->name) - 1,
                                 "%s-%s-%d", netdev->name, "rx", ri++);
                } else if (q_vector->tx.ring) {
                        snprintf(q_vector->name, sizeof(q_vector->name) - 1,
                                 "%s-%s-%d", netdev->name, "tx", ti++);
                } else {
                        /* skip this unused q_vector */
                        continue;
                }
                err = request_irq(entry->vector, &ixgbevf_msix_clean_rings, 0,
                                  q_vector->name, q_vector);
                if (err) {
                        hw_dbg(&adapter->hw,
                               "request_irq failed for MSIX interrupt "
                               "Error: %d\n", err);
                        goto free_queue_irqs;
                }
        }

        err = request_irq(adapter->msix_entries[vector].vector,
                          &ixgbevf_msix_other, 0, netdev->name, adapter);
        if (err) {
                hw_dbg(&adapter->hw,
                       "request_irq for msix_other failed: %d\n", err);
                goto free_queue_irqs;
        }

        return 0;

free_queue_irqs:
        while (vector) {
                vector--;
                free_irq(adapter->msix_entries[vector].vector,
                         adapter->q_vector[vector]);
        }
        /* This failure is non-recoverable - it indicates the system is
         * out of MSIX vector resources and the VF driver cannot run
         * without them.  Set the number of msix vectors to zero
         * indicating that not enough can be allocated.  The error
         * will be returned to the user indicating device open failed.
         * Any further attempts to force the driver to open will also
         * fail.  The only way to recover is to unload the driver and
         * reload it again.  If the system has recovered some MSIX
         * vectors then it may succeed.
         */
        adapter->num_msix_vectors = 0;
        return err;
}

static inline void ixgbevf_reset_q_vectors(struct ixgbevf_adapter *adapter)
{
        int i, q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;

        for (i = 0; i < q_vectors; i++) {
                struct ixgbevf_q_vector *q_vector = adapter->q_vector[i];
                q_vector->rx.ring = NULL;
                q_vector->tx.ring = NULL;
                q_vector->rx.count = 0;
                q_vector->tx.count = 0;
        }
}

/**
 * ixgbevf_request_irq - initialize interrupts
 * @adapter: board private structure
 *
 * Attempts to configure interrupts using the best available
 * capabilities of the hardware and kernel.
 **/
static int ixgbevf_request_irq(struct ixgbevf_adapter *adapter)
{
        int err = 0;

        err = ixgbevf_request_msix_irqs(adapter);

        if (err)
                hw_dbg(&adapter->hw,
                       "request_irq failed, Error %d\n", err);

        return err;
}

static void ixgbevf_free_irq(struct ixgbevf_adapter *adapter)

{
        int i, q_vectors;

        q_vectors = adapter->num_msix_vectors;
        i = q_vectors - 1;

        free_irq(adapter->msix_entries[i].vector, adapter);
        i--;

        for (; i >= 0; i--) {
                /* free only the irqs that were actually requested */
                if (!adapter->q_vector[i]->rx.ring &&
                    !adapter->q_vector[i]->tx.ring)
                        continue;

                free_irq(adapter->msix_entries[i].vector,
                         adapter->q_vector[i]);
        }

        ixgbevf_reset_q_vectors(adapter);
}

/**
 * ixgbevf_irq_disable - Mask off interrupt generation on the NIC
 * @adapter: board private structure
 **/
static inline void ixgbevf_irq_disable(struct ixgbevf_adapter *adapter)
{
        struct ixgbe_hw *hw = &adapter->hw;
        int i;

        IXGBE_WRITE_REG(hw, IXGBE_VTEIAM, 0);
        IXGBE_WRITE_REG(hw, IXGBE_VTEIMC, ~0);
        IXGBE_WRITE_REG(hw, IXGBE_VTEIAC, 0);

        IXGBE_WRITE_FLUSH(hw);

        for (i = 0; i < adapter->num_msix_vectors; i++)
                synchronize_irq(adapter->msix_entries[i].vector);
}

/**
 * ixgbevf_irq_enable - Enable default interrupt generation settings
 * @adapter: board private structure
 **/
static inline void ixgbevf_irq_enable(struct ixgbevf_adapter *adapter)
{
        struct ixgbe_hw *hw = &adapter->hw;

        IXGBE_WRITE_REG(hw, IXGBE_VTEIAM, adapter->eims_enable_mask);
        IXGBE_WRITE_REG(hw, IXGBE_VTEIAC, adapter->eims_enable_mask);
        IXGBE_WRITE_REG(hw, IXGBE_VTEIMS, adapter->eims_enable_mask);
}

/**
 * ixgbevf_configure_tx - Configure 82599 VF Transmit Unit after Reset
 * @adapter: board private structure
 *
 * Configure the Tx unit of the MAC after a reset.
 **/
static void ixgbevf_configure_tx(struct ixgbevf_adapter *adapter)
{
        u64 tdba;
        struct ixgbe_hw *hw = &adapter->hw;
        u32 i, j, tdlen, txctrl;

        /* Setup the HW Tx Head and Tail descriptor pointers */
        for (i = 0; i < adapter->num_tx_queues; i++) {
                struct ixgbevf_ring *ring = &adapter->tx_ring[i];
                j = ring->reg_idx;
                tdba = ring->dma;
                tdlen = ring->count * sizeof(union ixgbe_adv_tx_desc);
                IXGBE_WRITE_REG(hw, IXGBE_VFTDBAL(j),
                                (tdba & DMA_BIT_MASK(32)));
                IXGBE_WRITE_REG(hw, IXGBE_VFTDBAH(j), (tdba >> 32));
                IXGBE_WRITE_REG(hw, IXGBE_VFTDLEN(j), tdlen);
                IXGBE_WRITE_REG(hw, IXGBE_VFTDH(j), 0);
                IXGBE_WRITE_REG(hw, IXGBE_VFTDT(j), 0);
                adapter->tx_ring[i].head = IXGBE_VFTDH(j);
                adapter->tx_ring[i].tail = IXGBE_VFTDT(j);
                /* Disable Tx Head Writeback RO bit, since this hoses
                 * bookkeeping if things aren't delivered in order.
                 */
                txctrl = IXGBE_READ_REG(hw, IXGBE_VFDCA_TXCTRL(j));
                txctrl &= ~IXGBE_DCA_TXCTRL_TX_WB_RO_EN;
                IXGBE_WRITE_REG(hw, IXGBE_VFDCA_TXCTRL(j), txctrl);
        }
}

#define IXGBE_SRRCTL_BSIZEHDRSIZE_SHIFT 2

static void ixgbevf_configure_srrctl(struct ixgbevf_adapter *adapter, int index)
{
        struct ixgbevf_ring *rx_ring;
        struct ixgbe_hw *hw = &adapter->hw;
        u32 srrctl;

        rx_ring = &adapter->rx_ring[index];

        srrctl = IXGBE_SRRCTL_DROP_EN;

        srrctl |= IXGBE_SRRCTL_DESCTYPE_ADV_ONEBUF;

        srrctl |= ALIGN(rx_ring->rx_buf_len, 1024) >>
                  IXGBE_SRRCTL_BSIZEPKT_SHIFT;

        IXGBE_WRITE_REG(hw, IXGBE_VFSRRCTL(index), srrctl);
}

static void ixgbevf_set_rx_buffer_len(struct ixgbevf_adapter *adapter)
{
        struct ixgbe_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;
        int max_frame = netdev->mtu + ETH_HLEN + ETH_FCS_LEN;
        int i;
        u16 rx_buf_len;

        /* notify the PF of our intent to use this size of frame */
        ixgbevf_rlpml_set_vf(hw, max_frame);

        /* PF will allow an extra 4 bytes past for vlan tagged frames */
        max_frame += VLAN_HLEN;

        /*
         * Allocate buffer sizes that fit well into 32K and
         * take into account max frame size of 9.5K
         */
        if ((hw->mac.type == ixgbe_mac_X540_vf) &&
            (max_frame <= MAXIMUM_ETHERNET_VLAN_SIZE))
                rx_buf_len = MAXIMUM_ETHERNET_VLAN_SIZE;
        else if (max_frame <= IXGBEVF_RXBUFFER_2K)
                rx_buf_len = IXGBEVF_RXBUFFER_2K;
        else if (max_frame <= IXGBEVF_RXBUFFER_4K)
                rx_buf_len = IXGBEVF_RXBUFFER_4K;
        else if (max_frame <= IXGBEVF_RXBUFFER_8K)
                rx_buf_len = IXGBEVF_RXBUFFER_8K;
        else
                rx_buf_len = IXGBEVF_RXBUFFER_10K;

        for (i = 0; i < adapter->num_rx_queues; i++)
                adapter->rx_ring[i].rx_buf_len = rx_buf_len;
}

/**
 * ixgbevf_configure_rx - Configure 82599 VF Receive Unit after Reset
 * @adapter: board private structure
 *
 * Configure the Rx unit of the MAC after a reset.
 **/
static void ixgbevf_configure_rx(struct ixgbevf_adapter *adapter)
{
        u64 rdba;
        struct ixgbe_hw *hw = &adapter->hw;
        int i, j;
        u32 rdlen;

        /* PSRTYPE must be initialized in 82599 */
        IXGBE_WRITE_REG(hw, IXGBE_VFPSRTYPE, 0);

        /* set_rx_buffer_len must be called before ring initialization */
        ixgbevf_set_rx_buffer_len(adapter);

        rdlen = adapter->rx_ring[0].count * sizeof(union ixgbe_adv_rx_desc);
        /* Setup the HW Rx Head and Tail Descriptor Pointers and
         * the Base and Length of the Rx Descriptor Ring */
        for (i = 0; i < adapter->num_rx_queues; i++) {
                rdba = adapter->rx_ring[i].dma;
                j = adapter->rx_ring[i].reg_idx;
                IXGBE_WRITE_REG(hw, IXGBE_VFRDBAL(j),
                                (rdba & DMA_BIT_MASK(32)));
                IXGBE_WRITE_REG(hw, IXGBE_VFRDBAH(j), (rdba >> 32));
                IXGBE_WRITE_REG(hw, IXGBE_VFRDLEN(j), rdlen);
                IXGBE_WRITE_REG(hw, IXGBE_VFRDH(j), 0);
                IXGBE_WRITE_REG(hw, IXGBE_VFRDT(j), 0);
                adapter->rx_ring[i].head = IXGBE_VFRDH(j);
                adapter->rx_ring[i].tail = IXGBE_VFRDT(j);

                ixgbevf_configure_srrctl(adapter, j);
        }
}

static int ixgbevf_vlan_rx_add_vid(struct net_device *netdev,
                                   __be16 proto, u16 vid)
{
        struct ixgbevf_adapter *adapter = netdev_priv(netdev);
        struct ixgbe_hw *hw = &adapter->hw;
        int err;

        spin_lock_bh(&adapter->mbx_lock);

        /* add VID to filter table */
        err = hw->mac.ops.set_vfta(hw, vid, 0, true);

        spin_unlock_bh(&adapter->mbx_lock);

        /* translate error return types so error makes sense */
        if (err == IXGBE_ERR_MBX)
                return -EIO;

        if (err == IXGBE_ERR_INVALID_ARGUMENT)
                return -EACCES;

        set_bit(vid, adapter->active_vlans);

        return err;
}

static int ixgbevf_vlan_rx_kill_vid(struct net_device *netdev,
                                    __be16 proto, u16 vid)
{
        struct ixgbevf_adapter *adapter = netdev_priv(netdev);
        struct ixgbe_hw *hw = &adapter->hw;
        int err = -EOPNOTSUPP;

        spin_lock_bh(&adapter->mbx_lock);

        /* remove VID from filter table */
        err = hw->mac.ops.set_vfta(hw, vid, 0, false);

        spin_unlock_bh(&adapter->mbx_lock);

        clear_bit(vid, adapter->active_vlans);

        return err;
}

static void ixgbevf_restore_vlan(struct ixgbevf_adapter *adapter)
{
        u16 vid;

        for_each_set_bit(vid, adapter->active_vlans, VLAN_N_VID)
                ixgbevf_vlan_rx_add_vid(adapter->netdev,
                                        htons(ETH_P_8021Q), vid);
}

static int ixgbevf_write_uc_addr_list(struct net_device *netdev)
{
        struct ixgbevf_adapter *adapter = netdev_priv(netdev);
        struct ixgbe_hw *hw = &adapter->hw;
        int count = 0;

        if ((netdev_uc_count(netdev)) > 10) {
                pr_err("Too many unicast filters - No Space\n");
                return -ENOSPC;
        }

        if (!netdev_uc_empty(netdev)) {
                struct netdev_hw_addr *ha;
                netdev_for_each_uc_addr(ha, netdev) {
                        hw->mac.ops.set_uc_addr(hw, ++count, ha->addr);
                        udelay(200);
                }
        } else {
                /*
                 * If the list is empty then send message to PF driver to
                 * clear all macvlans on this VF.
                 */
                hw->mac.ops.set_uc_addr(hw, 0, NULL);
        }

        return count;
}

/**
 * ixgbevf_set_rx_mode - Multicast and unicast set
 * @netdev: network interface device structure
 *
 * The set_rx_method entry point is called whenever the multicast address
 * list, unicast address list or the network interface flags are updated.
 * This routine is responsible for configuring the hardware for proper
 * multicast mode and configuring requested unicast filters.
 **/
static void ixgbevf_set_rx_mode(struct net_device *netdev)
{
        struct ixgbevf_adapter *adapter = netdev_priv(netdev);
        struct ixgbe_hw *hw = &adapter->hw;

        spin_lock_bh(&adapter->mbx_lock);

        /* reprogram multicast list */
        hw->mac.ops.update_mc_addr_list(hw, netdev);

        ixgbevf_write_uc_addr_list(netdev);

        spin_unlock_bh(&adapter->mbx_lock);
}

static void ixgbevf_napi_enable_all(struct ixgbevf_adapter *adapter)
{
        int q_idx;
        struct ixgbevf_q_vector *q_vector;
        int q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;

        for (q_idx = 0; q_idx < q_vectors; q_idx++) {
                q_vector = adapter->q_vector[q_idx];
                napi_enable(&q_vector->napi);
        }
}

static void ixgbevf_napi_disable_all(struct ixgbevf_adapter *adapter)
{
        int q_idx;
        struct ixgbevf_q_vector *q_vector;
        int q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;

        for (q_idx = 0; q_idx < q_vectors; q_idx++) {
                q_vector = adapter->q_vector[q_idx];
                napi_disable(&q_vector->napi);
        }
}

static void ixgbevf_configure(struct ixgbevf_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        int i;

        ixgbevf_set_rx_mode(netdev);

        ixgbevf_restore_vlan(adapter);

        ixgbevf_configure_tx(adapter);
        ixgbevf_configure_rx(adapter);
        for (i = 0; i < adapter->num_rx_queues; i++) {
                struct ixgbevf_ring *ring = &adapter->rx_ring[i];
                ixgbevf_alloc_rx_buffers(adapter, ring,
                                         IXGBE_DESC_UNUSED(ring));
        }
}

#define IXGBE_MAX_RX_DESC_POLL 10
static inline void ixgbevf_rx_desc_queue_enable(struct ixgbevf_adapter *adapter,
                                                int rxr)
{
        struct ixgbe_hw *hw = &adapter->hw;
        int j = adapter->rx_ring[rxr].reg_idx;
        int k;

        for (k = 0; k < IXGBE_MAX_RX_DESC_POLL; k++) {
                if (IXGBE_READ_REG(hw, IXGBE_VFRXDCTL(j)) & IXGBE_RXDCTL_ENABLE)
                        break;
                else
                        msleep(1);
        }
        if (k >= IXGBE_MAX_RX_DESC_POLL) {
                hw_dbg(hw, "RXDCTL.ENABLE on Rx queue %d "
                       "not set within the polling period\n", rxr);
        }

        ixgbevf_release_rx_desc(hw, &adapter->rx_ring[rxr],
                                adapter->rx_ring[rxr].count - 1);
}

static void ixgbevf_save_reset_stats(struct ixgbevf_adapter *adapter)
{
        /* Only save pre-reset stats if there are some */
        if (adapter->stats.vfgprc || adapter->stats.vfgptc) {
                adapter->stats.saved_reset_vfgprc += adapter->stats.vfgprc -
                        adapter->stats.base_vfgprc;
                adapter->stats.saved_reset_vfgptc += adapter->stats.vfgptc -
                        adapter->stats.base_vfgptc;
                adapter->stats.saved_reset_vfgorc += adapter->stats.vfgorc -
                        adapter->stats.base_vfgorc;
                adapter->stats.saved_reset_vfgotc += adapter->stats.vfgotc -
                        adapter->stats.base_vfgotc;
                adapter->stats.saved_reset_vfmprc += adapter->stats.vfmprc -
                        adapter->stats.base_vfmprc;
        }
}

static void ixgbevf_init_last_counter_stats(struct ixgbevf_adapter *adapter)
{
        struct ixgbe_hw *hw = &adapter->hw;

        adapter->stats.last_vfgprc = IXGBE_READ_REG(hw, IXGBE_VFGPRC);
        adapter->stats.last_vfgorc = IXGBE_READ_REG(hw, IXGBE_VFGORC_LSB);
        adapter->stats.last_vfgorc |=
                (((u64)(IXGBE_READ_REG(hw, IXGBE_VFGORC_MSB))) << 32);
        adapter->stats.last_vfgptc = IXGBE_READ_REG(hw, IXGBE_VFGPTC);
        adapter->stats.last_vfgotc = IXGBE_READ_REG(hw, IXGBE_VFGOTC_LSB);
        adapter->stats.last_vfgotc |=
                (((u64)(IXGBE_READ_REG(hw, IXGBE_VFGOTC_MSB))) << 32);
        adapter->stats.last_vfmprc = IXGBE_READ_REG(hw, IXGBE_VFMPRC);

        adapter->stats.base_vfgprc = adapter->stats.last_vfgprc;
        adapter->stats.base_vfgorc = adapter->stats.last_vfgorc;
        adapter->stats.base_vfgptc = adapter->stats.last_vfgptc;
        adapter->stats.base_vfgotc = adapter->stats.last_vfgotc;
        adapter->stats.base_vfmprc = adapter->stats.last_vfmprc;
}

static void ixgbevf_negotiate_api(struct ixgbevf_adapter *adapter)
{
        struct ixgbe_hw *hw = &adapter->hw;
        int api[] = { ixgbe_mbox_api_11,
                      ixgbe_mbox_api_10,
                      ixgbe_mbox_api_unknown };
        int err = 0, idx = 0;

        spin_lock_bh(&adapter->mbx_lock);

        while (api[idx] != ixgbe_mbox_api_unknown) {
                err = ixgbevf_negotiate_api_version(hw, api[idx]);
                if (!err)
                        break;
                idx++;
        }

        spin_unlock_bh(&adapter->mbx_lock);
}

static void ixgbevf_up_complete(struct ixgbevf_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        struct ixgbe_hw *hw = &adapter->hw;
        int i, j = 0;
        int num_rx_rings = adapter->num_rx_queues;
        u32 txdctl, rxdctl;

        for (i = 0; i < adapter->num_tx_queues; i++) {
                j = adapter->tx_ring[i].reg_idx;
                txdctl = IXGBE_READ_REG(hw, IXGBE_VFTXDCTL(j));
                /* enable WTHRESH=8 descriptors, to encourage burst writeback */
                txdctl |= (8 << 16);
                IXGBE_WRITE_REG(hw, IXGBE_VFTXDCTL(j), txdctl);
        }

        for (i = 0; i < adapter->num_tx_queues; i++) {
                j = adapter->tx_ring[i].reg_idx;
                txdctl = IXGBE_READ_REG(hw, IXGBE_VFTXDCTL(j));
                txdctl |= IXGBE_TXDCTL_ENABLE;
                IXGBE_WRITE_REG(hw, IXGBE_VFTXDCTL(j), txdctl);
        }

        for (i = 0; i < num_rx_rings; i++) {
                j = adapter->rx_ring[i].reg_idx;
                rxdctl = IXGBE_READ_REG(hw, IXGBE_VFRXDCTL(j));
                rxdctl |= IXGBE_RXDCTL_ENABLE | IXGBE_RXDCTL_VME;
                if (hw->mac.type == ixgbe_mac_X540_vf) {
                        rxdctl &= ~IXGBE_RXDCTL_RLPMLMASK;
                        rxdctl |= ((netdev->mtu + ETH_HLEN + ETH_FCS_LEN) |
                                   IXGBE_RXDCTL_RLPML_EN);
                }
                IXGBE_WRITE_REG(hw, IXGBE_VFRXDCTL(j), rxdctl);
                ixgbevf_rx_desc_queue_enable(adapter, i);
        }

        ixgbevf_configure_msix(adapter);

        spin_lock_bh(&adapter->mbx_lock);

        if (is_valid_ether_addr(hw->mac.addr))
                hw->mac.ops.set_rar(hw, 0, hw->mac.addr, 0);
        else
                hw->mac.ops.set_rar(hw, 0, hw->mac.perm_addr, 0);

        spin_unlock_bh(&adapter->mbx_lock);

        clear_bit(__IXGBEVF_DOWN, &adapter->state);
        ixgbevf_napi_enable_all(adapter);

        /* enable transmits */
        netif_tx_start_all_queues(netdev);

        ixgbevf_save_reset_stats(adapter);
        ixgbevf_init_last_counter_stats(adapter);

        hw->mac.get_link_status = 1;
        mod_timer(&adapter->watchdog_timer, jiffies);
}

static int ixgbevf_reset_queues(struct ixgbevf_adapter *adapter)
{
        struct ixgbe_hw *hw = &adapter->hw;
        struct ixgbevf_ring *rx_ring;
        unsigned int def_q = 0;
        unsigned int num_tcs = 0;
        unsigned int num_rx_queues = 1;
        int err, i;

        spin_lock_bh(&adapter->mbx_lock);

        /* fetch queue configuration from the PF */
        err = ixgbevf_get_queues(hw, &num_tcs, &def_q);

        spin_unlock_bh(&adapter->mbx_lock);

        if (err)
                return err;

        if (num_tcs > 1) {
                /* update default Tx ring register index */
                adapter->tx_ring[0].reg_idx = def_q;

                /* we need as many queues as traffic classes */
                num_rx_queues = num_tcs;
        }

        /* nothing to do if we have the correct number of queues */
        if (adapter->num_rx_queues == num_rx_queues)
                return 0;

        /* allocate new rings */
        rx_ring = kcalloc(num_rx_queues,
                          sizeof(struct ixgbevf_ring), GFP_KERNEL);
        if (!rx_ring)
                return -ENOMEM;

        /* setup ring fields */
        for (i = 0; i < num_rx_queues; i++) {
                rx_ring[i].count = adapter->rx_ring_count;
                rx_ring[i].queue_index = i;
                rx_ring[i].reg_idx = i;
                rx_ring[i].dev = &adapter->pdev->dev;
                rx_ring[i].netdev = adapter->netdev;

                /* allocate resources on the ring */
                err = ixgbevf_setup_rx_resources(adapter, &rx_ring[i]);
                if (err) {
                        while (i) {
                                i--;
                                ixgbevf_free_rx_resources(adapter, &rx_ring[i]);
                        }
                        kfree(rx_ring);
                        return err;
                }
        }

        /* free the existing rings and queues */
        ixgbevf_free_all_rx_resources(adapter);
        adapter->num_rx_queues = 0;
        kfree(adapter->rx_ring);

        /* move new rings into position on the adapter struct */
        adapter->rx_ring = rx_ring;
        adapter->num_rx_queues = num_rx_queues;

        /* reset ring to vector mapping */
        ixgbevf_reset_q_vectors(adapter);
        ixgbevf_map_rings_to_vectors(adapter);

        return 0;
}

void ixgbevf_up(struct ixgbevf_adapter *adapter)
{
        struct ixgbe_hw *hw = &adapter->hw;

        ixgbevf_negotiate_api(adapter);

        ixgbevf_reset_queues(adapter);

        ixgbevf_configure(adapter);

        ixgbevf_up_complete(adapter);

        /* clear any pending interrupts, may auto mask */
        IXGBE_READ_REG(hw, IXGBE_VTEICR);

        ixgbevf_irq_enable(adapter);
}

/**
 * ixgbevf_clean_rx_ring - Free Rx Buffers per Queue
 * @adapter: board private structure
 * @rx_ring: ring to free buffers from
 **/
static void ixgbevf_clean_rx_ring(struct ixgbevf_adapter *adapter,
                                  struct ixgbevf_ring *rx_ring)
{
        struct pci_dev *pdev = adapter->pdev;
        unsigned long size;
        unsigned int i;

        if (!rx_ring->rx_buffer_info)
                return;

        /* Free all the Rx ring sk_buffs */
        for (i = 0; i < rx_ring->count; i++) {
                struct ixgbevf_rx_buffer *rx_buffer_info;

                rx_buffer_info = &rx_ring->rx_buffer_info[i];
                if (rx_buffer_info->dma) {
                        dma_unmap_single(&pdev->dev, rx_buffer_info->dma,
                                         rx_ring->rx_buf_len,
                                         DMA_FROM_DEVICE);
                        rx_buffer_info->dma = 0;
                }
                if (rx_buffer_info->skb) {
                        struct sk_buff *skb = rx_buffer_info->skb;
                        rx_buffer_info->skb = NULL;
                        do {
                                struct sk_buff *this = skb;
                                skb = IXGBE_CB(skb)->prev;
                                dev_kfree_skb(this);
                        } while (skb);
                }
        }

        size = sizeof(struct ixgbevf_rx_buffer) * rx_ring->count;
        memset(rx_ring->rx_buffer_info, 0, size);

        /* Zero out the descriptor ring */
        memset(rx_ring->desc, 0, rx_ring->size);

        rx_ring->next_to_clean = 0;
        rx_ring->next_to_use = 0;

        if (rx_ring->head)
                writel(0, adapter->hw.hw_addr + rx_ring->head);
        if (rx_ring->tail)
                writel(0, adapter->hw.hw_addr + rx_ring->tail);
}

/**
 * ixgbevf_clean_tx_ring - Free Tx Buffers
 * @adapter: board private structure
 * @tx_ring: ring to be cleaned
 **/
static void ixgbevf_clean_tx_ring(struct ixgbevf_adapter *adapter,
                                  struct ixgbevf_ring *tx_ring)
{
        struct ixgbevf_tx_buffer *tx_buffer_info;
        unsigned long size;
        unsigned int i;

        if (!tx_ring->tx_buffer_info)
                return;

        /* Free all the Tx ring sk_buffs */
        for (i = 0; i < tx_ring->count; i++) {
                tx_buffer_info = &tx_ring->tx_buffer_info[i];
                ixgbevf_unmap_and_free_tx_resource(tx_ring, tx_buffer_info);
        }

        size = sizeof(struct ixgbevf_tx_buffer) * tx_ring->count;
        memset(tx_ring->tx_buffer_info, 0, size);

        memset(tx_ring->desc, 0, tx_ring->size);

        tx_ring->next_to_use = 0;
        tx_ring->next_to_clean = 0;

        if (tx_ring->head)
                writel(0, adapter->hw.hw_addr + tx_ring->head);
        if (tx_ring->tail)
                writel(0, adapter->hw.hw_addr + tx_ring->tail);
}

/**
 * ixgbevf_clean_all_rx_rings - Free Rx Buffers for all queues
 * @adapter: board private structure
 **/
static void ixgbevf_clean_all_rx_rings(struct ixgbevf_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_rx_queues; i++)
                ixgbevf_clean_rx_ring(adapter, &adapter->rx_ring[i]);
}

/**
 * ixgbevf_clean_all_tx_rings - Free Tx Buffers for all queues
 * @adapter: board private structure
 **/
static void ixgbevf_clean_all_tx_rings(struct ixgbevf_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_tx_queues; i++)
                ixgbevf_clean_tx_ring(adapter, &adapter->tx_ring[i]);
}

void ixgbevf_down(struct ixgbevf_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        struct ixgbe_hw *hw = &adapter->hw;
        u32 txdctl;
        int i, j;

        /* signal that we are down to the interrupt handler */
        set_bit(__IXGBEVF_DOWN, &adapter->state);
        /* disable receives */

        netif_tx_disable(netdev);

        msleep(10);

        netif_tx_stop_all_queues(netdev);

        ixgbevf_irq_disable(adapter);

        ixgbevf_napi_disable_all(adapter);

        del_timer_sync(&adapter->watchdog_timer);
        /* can't call flush scheduled work here because it can deadlock
         * if linkwatch_event tries to acquire the rtnl_lock which we are
         * holding */
        while (adapter->flags & IXGBE_FLAG_IN_WATCHDOG_TASK)
                msleep(1);

        /* disable transmits in the hardware now that interrupts are off */
        for (i = 0; i < adapter->num_tx_queues; i++) {
                j = adapter->tx_ring[i].reg_idx;
                txdctl = IXGBE_READ_REG(hw, IXGBE_VFTXDCTL(j));
                IXGBE_WRITE_REG(hw, IXGBE_VFTXDCTL(j),
                                (txdctl & ~IXGBE_TXDCTL_ENABLE));
        }

        netif_carrier_off(netdev);

        if (!pci_channel_offline(adapter->pdev))
                ixgbevf_reset(adapter);

        ixgbevf_clean_all_tx_rings(adapter);
        ixgbevf_clean_all_rx_rings(adapter);
}

void ixgbevf_reinit_locked(struct ixgbevf_adapter *adapter)
{
        WARN_ON(in_interrupt());

        while (test_and_set_bit(__IXGBEVF_RESETTING, &adapter->state))
                msleep(1);

        ixgbevf_down(adapter);
        ixgbevf_up(adapter);

        clear_bit(__IXGBEVF_RESETTING, &adapter->state);
}

void ixgbevf_reset(struct ixgbevf_adapter *adapter)
{
        struct ixgbe_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;

        if (hw->mac.ops.reset_hw(hw))
                hw_dbg(hw, "PF still resetting\n");
        else
                hw->mac.ops.init_hw(hw);

        if (is_valid_ether_addr(adapter->hw.mac.addr)) {
                memcpy(netdev->dev_addr, adapter->hw.mac.addr,
                       netdev->addr_len);
                memcpy(netdev->perm_addr, adapter->hw.mac.addr,
                       netdev->addr_len);
        }
}

static int ixgbevf_acquire_msix_vectors(struct ixgbevf_adapter *adapter,
                                        int vectors)
{
        int err = 0;
        int vector_threshold;

        /* We'll want at least 2 (vector_threshold):
         * 1) TxQ[0] + RxQ[0] handler
         * 2) Other (Link Status Change, etc.)
         */
        vector_threshold = MIN_MSIX_COUNT;

        /* The more we get, the more we will assign to Tx/Rx Cleanup
         * for the separate queues...where Rx Cleanup >= Tx Cleanup.
         * Right now, we simply care about how many we'll get; we'll
         * set them up later while requesting irq's.
         */
        while (vectors >= vector_threshold) {
                err = pci_enable_msix(adapter->pdev, adapter->msix_entries,
                                      vectors);
                if (!err || err < 0) /* Success or a nasty failure. */
                        break;
                else /* err == number of vectors we should try again with */
                        vectors = err;
        }

        if (vectors < vector_threshold)
                err = -ENOMEM;

        if (err) {
                dev_err(&adapter->pdev->dev,
                        "Unable to allocate MSI-X interrupts\n");
                kfree(adapter->msix_entries);
                adapter->msix_entries = NULL;
        } else {
                /*
                 * Adjust for only the vectors we'll use, which is minimum
                 * of max_msix_q_vectors + NON_Q_VECTORS, or the number of
                 * vectors we were allocated.
                 */
                adapter->num_msix_vectors = vectors;
        }

        return err;
}

/**
 * ixgbevf_set_num_queues - Allocate queues for device, feature dependent
 * @adapter: board private structure to initialize
 *
 * This is the top level queue allocation routine.  The order here is very
 * important, starting with the "most" number of features turned on at once,
 * and ending with the smallest set of features.  This way large combinations
 * can be allocated if they're turned on, and smaller combinations are the
 * fallthrough conditions.
 *
 **/
static void ixgbevf_set_num_queues(struct ixgbevf_adapter *adapter)
{
        /* Start with base case */
        adapter->num_rx_queues = 1;
        adapter->num_tx_queues = 1;
}

/**
 * ixgbevf_alloc_queues - Allocate memory for all rings
 * @adapter: board private structure to initialize
 *
 * We allocate one ring per queue at run-time since we don't know the
 * number of queues at compile-time.  The polling_netdev array is
 * intended for Multiqueue, but should work fine with a single queue.
 **/
static int ixgbevf_alloc_queues(struct ixgbevf_adapter *adapter)
{
        int i;

        adapter->tx_ring = kcalloc(adapter->num_tx_queues,
                                   sizeof(struct ixgbevf_ring), GFP_KERNEL);
        if (!adapter->tx_ring)
                goto err_tx_ring_allocation;

        adapter->rx_ring = kcalloc(adapter->num_rx_queues,
                                   sizeof(struct ixgbevf_ring), GFP_KERNEL);
        if (!adapter->rx_ring)
                goto err_rx_ring_allocation;

        for (i = 0; i < adapter->num_tx_queues; i++) {
                adapter->tx_ring[i].count = adapter->tx_ring_count;
                adapter->tx_ring[i].queue_index = i;
                /* reg_idx may be remapped later by DCB config */
                adapter->tx_ring[i].reg_idx = i;
                adapter->tx_ring[i].dev = &adapter->pdev->dev;
                adapter->tx_ring[i].netdev = adapter->netdev;
        }

        for (i = 0; i < adapter->num_rx_queues; i++) {
                adapter->rx_ring[i].count = adapter->rx_ring_count;
                adapter->rx_ring[i].queue_index = i;
                adapter->rx_ring[i].reg_idx = i;
                adapter->rx_ring[i].dev = &adapter->pdev->dev;
                adapter->rx_ring[i].netdev = adapter->netdev;
        }

        return 0;

err_rx_ring_allocation:
        kfree(adapter->tx_ring);
err_tx_ring_allocation:
        return -ENOMEM;
}

/**
 * ixgbevf_set_interrupt_capability - set MSI-X or FAIL if not supported
 * @adapter: board private structure to initialize
 *
 * Attempt to configure the interrupts using the best available
 * capabilities of the hardware and the kernel.
 **/
static int ixgbevf_set_interrupt_capability(struct ixgbevf_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        int err = 0;
        int vector, v_budget;

        /*
         * It's easy to be greedy for MSI-X vectors, but it really
         * doesn't do us much good if we have a lot more vectors
         * than CPU's.  So let's be conservative and only ask for
         * (roughly) the same number of vectors as there are CPU's.
         * The default is to use pairs of vectors.
         */
        v_budget = max(adapter->num_rx_queues, adapter->num_tx_queues);
        v_budget = min_t(int, v_budget, num_online_cpus());
        v_budget += NON_Q_VECTORS;

        /* A failure in MSI-X entry allocation isn't fatal, but it does
         * mean we disable MSI-X capabilities of the adapter. */
        adapter->msix_entries = kcalloc(v_budget,
                                        sizeof(struct msix_entry), GFP_KERNEL);
        if (!adapter->msix_entries) {
                err = -ENOMEM;
                goto out;
        }

        for (vector = 0; vector < v_budget; vector++)
                adapter->msix_entries[vector].entry = vector;

        err = ixgbevf_acquire_msix_vectors(adapter, v_budget);
        if (err)
                goto out;

        err = netif_set_real_num_tx_queues(netdev, adapter->num_tx_queues);
        if (err)
                goto out;

        err = netif_set_real_num_rx_queues(netdev, adapter->num_rx_queues);

out:
        return err;
}

/**
 * ixgbevf_alloc_q_vectors - Allocate memory for interrupt vectors
 * @adapter: board private structure to initialize
 *
 * We allocate one q_vector per queue interrupt.  If allocation fails we
 * return -ENOMEM.
 **/
static int ixgbevf_alloc_q_vectors(struct ixgbevf_adapter *adapter)
{
        int q_idx, num_q_vectors;
        struct ixgbevf_q_vector *q_vector;

        num_q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;

        for (q_idx = 0; q_idx < num_q_vectors; q_idx++) {
                q_vector = kzalloc(sizeof(struct ixgbevf_q_vector), GFP_KERNEL);
                if (!q_vector)
                        goto err_out;
                q_vector->adapter = adapter;
                q_vector->v_idx = q_idx;
                netif_napi_add(adapter->netdev, &q_vector->napi,
                               ixgbevf_poll, 64);
                adapter->q_vector[q_idx] = q_vector;
        }

        return 0;

err_out:
        while (q_idx) {
                q_idx--;
                q_vector = adapter->q_vector[q_idx];
                netif_napi_del(&q_vector->napi);
                kfree(q_vector);
                adapter->q_vector[q_idx] = NULL;
        }
        return -ENOMEM;
}

/**
 * ixgbevf_free_q_vectors - Free memory allocated for interrupt vectors
 * @adapter: board private structure to initialize
 *
 * This function frees the memory allocated to the q_vectors.  In addition if
 * NAPI is enabled it will delete any references to the NAPI struct prior
 * to freeing the q_vector.
 **/
static void ixgbevf_free_q_vectors(struct ixgbevf_adapter *adapter)
{
        int q_idx, num_q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;

        for (q_idx = 0; q_idx < num_q_vectors; q_idx++) {
                struct ixgbevf_q_vector *q_vector = adapter->q_vector[q_idx];

                adapter->q_vector[q_idx] = NULL;
                netif_napi_del(&q_vector->napi);
                kfree(q_vector);
        }
}

/**
 * ixgbevf_reset_interrupt_capability - Reset MSIX setup
 * @adapter: board private structure
 *
 **/
static void ixgbevf_reset_interrupt_capability(struct ixgbevf_adapter *adapter)
{
        pci_disable_msix(adapter->pdev);
        kfree(adapter->msix_entries);
        adapter->msix_entries = NULL;
}

/**
 * ixgbevf_init_interrupt_scheme - Determine if MSIX is supported and init
 * @adapter: board private structure to initialize
 *
 **/
static int ixgbevf_init_interrupt_scheme(struct ixgbevf_adapter *adapter)
{
        int err;

        /* Number of supported queues */
        ixgbevf_set_num_queues(adapter);

        err = ixgbevf_set_interrupt_capability(adapter);
        if (err) {
                hw_dbg(&adapter->hw,
                       "Unable to setup interrupt capabilities\n");
                goto err_set_interrupt;
        }

        err = ixgbevf_alloc_q_vectors(adapter);

        if (err) {
                hw_dbg(&adapter->hw, "Unable to allocate memory for queue "
                       "vectors\n");
                goto err_alloc_q_vectors;
        }

        err = ixgbevf_alloc_queues(adapter);
        if (err) {
                pr_err("Unable to allocate memory for queues\n");
                goto err_alloc_queues;
        }

        hw_dbg(&adapter->hw, "Multiqueue %s: Rx Queue count = %u, "
               "Tx Queue count = %u\n",
               (adapter->num_rx_queues > 1) ? "Enabled" :
               "Disabled", adapter->num_rx_queues, adapter->num_tx_queues);

        set_bit(__IXGBEVF_DOWN, &adapter->state);

        return 0;
err_alloc_queues:
        ixgbevf_free_q_vectors(adapter);
err_alloc_q_vectors:
        ixgbevf_reset_interrupt_capability(adapter);
err_set_interrupt:
        return err;
}

/**
 * ixgbevf_clear_interrupt_scheme - Clear the current interrupt scheme settings
 * @adapter: board private structure to clear interrupt scheme on
 *
 * We go through and clear interrupt specific resources and reset the structure
 * to pre-load conditions
 **/
static void ixgbevf_clear_interrupt_scheme(struct ixgbevf_adapter *adapter)
{
        adapter->num_tx_queues = 0;
        adapter->num_rx_queues = 0;

        ixgbevf_free_q_vectors(adapter);
        ixgbevf_reset_interrupt_capability(adapter);
}

/**
 * ixgbevf_sw_init - Initialize general software structures
 * (struct ixgbevf_adapter)
 * @adapter: board private structure to initialize
 *
 * ixgbevf_sw_init initializes the Adapter private data structure.
 * Fields are initialized based on PCI device information and
 * OS network device settings (MTU size).
 **/
static int ixgbevf_sw_init(struct ixgbevf_adapter *adapter)
{
        struct ixgbe_hw *hw = &adapter->hw;
        struct pci_dev *pdev = adapter->pdev;
        struct net_device *netdev = adapter->netdev;
        int err;

        /* PCI config space info */

        hw->vendor_id = pdev->vendor;
        hw->device_id = pdev->device;
        hw->revision_id = pdev->revision;
        hw->subsystem_vendor_id = pdev->subsystem_vendor;
        hw->subsystem_device_id = pdev->subsystem_device;

        hw->mbx.ops.init_params(hw);

        /* assume legacy case in which PF would only give VF 2 queues */
        hw->mac.max_tx_queues = 2;
        hw->mac.max_rx_queues = 2;

        err = hw->mac.ops.reset_hw(hw);
        if (err) {
                dev_info(&pdev->dev,
                         "PF still in reset state.  Is the PF interface up?\n");
        } else {
                err = hw->mac.ops.init_hw(hw);
                if (err) {
                        pr_err("init_shared_code failed: %d\n", err);
                        goto out;
                }
                err = hw->mac.ops.get_mac_addr(hw, hw->mac.addr);
                if (err)
                        dev_info(&pdev->dev, "Error reading MAC address\n");
                else if (is_zero_ether_addr(adapter->hw.mac.addr))
                        dev_info(&pdev->dev,
                                 "MAC address not assigned by administrator.\n");
                memcpy(netdev->dev_addr, hw->mac.addr, netdev->addr_len);
        }

        if (!is_valid_ether_addr(netdev->dev_addr)) {
                dev_info(&pdev->dev, "Assigning random MAC address\n");
                eth_hw_addr_random(netdev);
                memcpy(hw->mac.addr, netdev->dev_addr, netdev->addr_len);
        }

        /* lock to protect mailbox accesses */
        spin_lock_init(&adapter->mbx_lock);

        /* Enable dynamic interrupt throttling rates */
        adapter->rx_itr_setting = 1;
        adapter->tx_itr_setting = 1;

        /* set default ring sizes */
        adapter->tx_ring_count = IXGBEVF_DEFAULT_TXD;
        adapter->rx_ring_count = IXGBEVF_DEFAULT_RXD;

        set_bit(__IXGBEVF_DOWN, &adapter->state);
        return 0;

out:
        return err;
}

#define UPDATE_VF_COUNTER_32bit(reg, last_counter, counter)     \
        {                                                       \
                u32 current_counter = IXGBE_READ_REG(hw, reg);  \
                if (current_counter < last_counter)             \
                        counter += 0x100000000LL;               \
                last_counter = current_counter;                 \
                counter &= 0xFFFFFFFF00000000LL;                \
                counter |= current_counter;                     \
        }

#define UPDATE_VF_COUNTER_36bit(reg_lsb, reg_msb, last_counter, counter) \
        {                                                                \
                u64 current_counter_lsb = IXGBE_READ_REG(hw, reg_lsb);   \
                u64 current_counter_msb = IXGBE_READ_REG(hw, reg_msb);   \
                u64 current_counter = (current_counter_msb << 32) |      \
                        current_counter_lsb;                             \
                if (current_counter < last_counter)                      \
                        counter += 0x1000000000LL;                       \
                last_counter = current_counter;                          \
                counter &= 0xFFFFFFF000000000LL;                         \
                counter |= current_counter;                              \
        }
/**
 * ixgbevf_update_stats - Update the board statistics counters.
 * @adapter: board private structure
 **/
void ixgbevf_update_stats(struct ixgbevf_adapter *adapter)
{
        struct ixgbe_hw *hw = &adapter->hw;
        int i;

        if (!adapter->link_up)
                return;

        UPDATE_VF_COUNTER_32bit(IXGBE_VFGPRC, adapter->stats.last_vfgprc,
                                adapter->stats.vfgprc);
        UPDATE_VF_COUNTER_32bit(IXGBE_VFGPTC, adapter->stats.last_vfgptc,
                                adapter->stats.vfgptc);
        UPDATE_VF_COUNTER_36bit(IXGBE_VFGORC_LSB, IXGBE_VFGORC_MSB,
                                adapter->stats.last_vfgorc,
                                adapter->stats.vfgorc);
        UPDATE_VF_COUNTER_36bit(IXGBE_VFGOTC_LSB, IXGBE_VFGOTC_MSB,
                                adapter->stats.last_vfgotc,
                                adapter->stats.vfgotc);
        UPDATE_VF_COUNTER_32bit(IXGBE_VFMPRC, adapter->stats.last_vfmprc,
                                adapter->stats.vfmprc);

        for (i = 0;  i  < adapter->num_rx_queues;  i++) {
                adapter->hw_csum_rx_error +=
                        adapter->rx_ring[i].hw_csum_rx_error;
                adapter->hw_csum_rx_good +=
                        adapter->rx_ring[i].hw_csum_rx_good;
                adapter->rx_ring[i].hw_csum_rx_error = 0;
                adapter->rx_ring[i].hw_csum_rx_good = 0;
        }
}

/**
 * ixgbevf_watchdog - Timer Call-back
 * @data: pointer to adapter cast into an unsigned long
 **/
static void ixgbevf_watchdog(unsigned long data)
{
        struct ixgbevf_adapter *adapter = (struct ixgbevf_adapter *)data;
        struct ixgbe_hw *hw = &adapter->hw;
        u32 eics = 0;
        int i;

        /*
         * Do the watchdog outside of interrupt context due to the lovely
         * delays that some of the newer hardware requires
         */

        if (test_bit(__IXGBEVF_DOWN, &adapter->state))
                goto watchdog_short_circuit;

        /* get one bit for every active tx/rx interrupt vector */
        for (i = 0; i < adapter->num_msix_vectors - NON_Q_VECTORS; i++) {
                struct ixgbevf_q_vector *qv = adapter->q_vector[i];
                if (qv->rx.ring || qv->tx.ring)
                        eics |= 1 << i;
        }

        IXGBE_WRITE_REG(hw, IXGBE_VTEICS, eics);

watchdog_short_circuit:
        schedule_work(&adapter->watchdog_task);
}

/**
 * ixgbevf_tx_timeout - Respond to a Tx Hang
 * @netdev: network interface device structure
 **/
static void ixgbevf_tx_timeout(struct net_device *netdev)
{
        struct ixgbevf_adapter *adapter = netdev_priv(netdev);

        /* Do the reset outside of interrupt context */
        schedule_work(&adapter->reset_task);
}

static void ixgbevf_reset_task(struct work_struct *work)
{
        struct ixgbevf_adapter *adapter;
        adapter = container_of(work, struct ixgbevf_adapter, reset_task);

        /* If we're already down or resetting, just bail */
        if (test_bit(__IXGBEVF_DOWN, &adapter->state) ||
            test_bit(__IXGBEVF_RESETTING, &adapter->state))
                return;

        adapter->tx_timeout_count++;

        ixgbevf_reinit_locked(adapter);
}

/**
 * ixgbevf_watchdog_task - worker thread to bring link up
 * @work: pointer to work_struct containing our data
 **/
static void ixgbevf_watchdog_task(struct work_struct *work)
{
        struct ixgbevf_adapter *adapter = container_of(work,
                                                       struct ixgbevf_adapter,
                                                       watchdog_task);
        struct net_device *netdev = adapter->netdev;
        struct ixgbe_hw *hw = &adapter->hw;
        u32 link_speed = adapter->link_speed;
        bool link_up = adapter->link_up;
        s32 need_reset;

        adapter->flags |= IXGBE_FLAG_IN_WATCHDOG_TASK;

        /*
         * Always check the link on the watchdog because we have
         * no LSC interrupt
         */
        spin_lock_bh(&adapter->mbx_lock);

        need_reset = hw->mac.ops.check_link(hw, &link_speed, &link_up, false);

        spin_unlock_bh(&adapter->mbx_lock);

        if (need_reset) {
                adapter->link_up = link_up;
                adapter->link_speed = link_speed;
                netif_carrier_off(netdev);
                netif_tx_stop_all_queues(netdev);
                schedule_work(&adapter->reset_task);
                goto pf_has_reset;
        }
        adapter->link_up = link_up;
        adapter->link_speed = link_speed;

        if (link_up) {
                if (!netif_carrier_ok(netdev)) {
                        char *link_speed_string;
                        switch (link_speed) {
                        case IXGBE_LINK_SPEED_10GB_FULL:
                                link_speed_string = "10 Gbps";
                                break;
                        case IXGBE_LINK_SPEED_1GB_FULL:
                                link_speed_string = "1 Gbps";
                                break;
                        case IXGBE_LINK_SPEED_100_FULL:
                                link_speed_string = "100 Mbps";
                                break;
                        default:
                                link_speed_string = "unknown speed";
                                break;
                        }
                        dev_info(&adapter->pdev->dev,
                                "NIC Link is Up, %s\n", link_speed_string);
                        netif_carrier_on(netdev);
                        netif_tx_wake_all_queues(netdev);
                }
        } else {
                adapter->link_up = false;
                adapter->link_speed = 0;
                if (netif_carrier_ok(netdev)) {
                        dev_info(&adapter->pdev->dev, "NIC Link is Down\n");
                        netif_carrier_off(netdev);
                        netif_tx_stop_all_queues(netdev);
                }
        }

        ixgbevf_update_stats(adapter);

pf_has_reset:
        /* Reset the timer */
        if (!test_bit(__IXGBEVF_DOWN, &adapter->state))
                mod_timer(&adapter->watchdog_timer,
                          round_jiffies(jiffies + (2 * HZ)));

        adapter->flags &= ~IXGBE_FLAG_IN_WATCHDOG_TASK;
}

/**
 * ixgbevf_free_tx_resources - Free Tx Resources per Queue
 * @adapter: board private structure
 * @tx_ring: Tx descriptor ring for a specific queue
 *
 * Free all transmit software resources
 **/
void ixgbevf_free_tx_resources(struct ixgbevf_adapter *adapter,
                               struct ixgbevf_ring *tx_ring)
{
        struct pci_dev *pdev = adapter->pdev;

        ixgbevf_clean_tx_ring(adapter, tx_ring);

        vfree(tx_ring->tx_buffer_info);
        tx_ring->tx_buffer_info = NULL;

        dma_free_coherent(&pdev->dev, tx_ring->size, tx_ring->desc,
                          tx_ring->dma);

        tx_ring->desc = NULL;
}

/**
 * ixgbevf_free_all_tx_resources - Free Tx Resources for All Queues
 * @adapter: board private structure
 *
 * Free all transmit software resources
 **/
static void ixgbevf_free_all_tx_resources(struct ixgbevf_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_tx_queues; i++)
                if (adapter->tx_ring[i].desc)
                        ixgbevf_free_tx_resources(adapter,
                                                  &adapter->tx_ring[i]);

}

/**
 * ixgbevf_setup_tx_resources - allocate Tx resources (Descriptors)
 * @adapter: board private structure
 * @tx_ring:    tx descriptor ring (for a specific queue) to setup
 *
 * Return 0 on success, negative on failure
 **/
int ixgbevf_setup_tx_resources(struct ixgbevf_adapter *adapter,
                               struct ixgbevf_ring *tx_ring)
{
        struct pci_dev *pdev = adapter->pdev;
        int size;

        size = sizeof(struct ixgbevf_tx_buffer) * tx_ring->count;
        tx_ring->tx_buffer_info = vzalloc(size);
        if (!tx_ring->tx_buffer_info)
                goto err;

        /* round up to nearest 4K */
        tx_ring->size = tx_ring->count * sizeof(union ixgbe_adv_tx_desc);
        tx_ring->size = ALIGN(tx_ring->size, 4096);

        tx_ring->desc = dma_alloc_coherent(&pdev->dev, tx_ring->size,
                                           &tx_ring->dma, GFP_KERNEL);
        if (!tx_ring->desc)
                goto err;

        tx_ring->next_to_use = 0;
        tx_ring->next_to_clean = 0;
        return 0;

err:
        vfree(tx_ring->tx_buffer_info);
        tx_ring->tx_buffer_info = NULL;
        hw_dbg(&adapter->hw, "Unable to allocate memory for the transmit "
               "descriptor ring\n");
        return -ENOMEM;
}

/**
 * ixgbevf_setup_all_tx_resources - allocate all queues Tx resources
 * @adapter: board private structure
 *
 * If this function returns with an error, then it's possible one or
 * more of the rings is populated (while the rest are not).  It is the
 * callers duty to clean those orphaned rings.
 *
 * Return 0 on success, negative on failure
 **/
static int ixgbevf_setup_all_tx_resources(struct ixgbevf_adapter *adapter)
{
        int i, err = 0;

        for (i = 0; i < adapter->num_tx_queues; i++) {
                err = ixgbevf_setup_tx_resources(adapter, &adapter->tx_ring[i]);
                if (!err)
                        continue;
                hw_dbg(&adapter->hw,
                       "Allocation for Tx Queue %u failed\n", i);
                break;
        }

        return err;
}

/**
 * ixgbevf_setup_rx_resources - allocate Rx resources (Descriptors)
 * @adapter: board private structure
 * @rx_ring:    rx descriptor ring (for a specific queue) to setup
 *
 * Returns 0 on success, negative on failure
 **/
int ixgbevf_setup_rx_resources(struct ixgbevf_adapter *adapter,
                               struct ixgbevf_ring *rx_ring)
{
        struct pci_dev *pdev = adapter->pdev;
        int size;

        size = sizeof(struct ixgbevf_rx_buffer) * rx_ring->count;
        rx_ring->rx_buffer_info = vzalloc(size);
        if (!rx_ring->rx_buffer_info)
                goto alloc_failed;

        /* Round up to nearest 4K */
        rx_ring->size = rx_ring->count * sizeof(union ixgbe_adv_rx_desc);
        rx_ring->size = ALIGN(rx_ring->size, 4096);

        rx_ring->desc = dma_alloc_coherent(&pdev->dev, rx_ring->size,
                                           &rx_ring->dma, GFP_KERNEL);

        if (!rx_ring->desc) {
                vfree(rx_ring->rx_buffer_info);
                rx_ring->rx_buffer_info = NULL;
                goto alloc_failed;
        }

        rx_ring->next_to_clean = 0;
        rx_ring->next_to_use = 0;

        return 0;
alloc_failed:
        return -ENOMEM;
}

/**
 * ixgbevf_setup_all_rx_resources - allocate all queues Rx resources
 * @adapter: board private structure
 *
 * If this function returns with an error, then it's possible one or
 * more of the rings is populated (while the rest are not).  It is the
 * callers duty to clean those orphaned rings.
 *
 * Return 0 on success, negative on failure
 **/
static int ixgbevf_setup_all_rx_resources(struct ixgbevf_adapter *adapter)
{
        int i, err = 0;

        for (i = 0; i < adapter->num_rx_queues; i++) {
                err = ixgbevf_setup_rx_resources(adapter, &adapter->rx_ring[i]);
                if (!err)
                        continue;
                hw_dbg(&adapter->hw,
                       "Allocation for Rx Queue %u failed\n", i);
                break;
        }
        return err;
}

/**
 * ixgbevf_free_rx_resources - Free Rx Resources
 * @adapter: board private structure
 * @rx_ring: ring to clean the resources from
 *
 * Free all receive software resources
 **/
void ixgbevf_free_rx_resources(struct ixgbevf_adapter *adapter,
                               struct ixgbevf_ring *rx_ring)
{
        struct pci_dev *pdev = adapter->pdev;

        ixgbevf_clean_rx_ring(adapter, rx_ring);

        vfree(rx_ring->rx_buffer_info);
        rx_ring->rx_buffer_info = NULL;

        dma_free_coherent(&pdev->dev, rx_ring->size, rx_ring->desc,
                          rx_ring->dma);

        rx_ring->desc = NULL;
}

/**
 * ixgbevf_free_all_rx_resources - Free Rx Resources for All Queues
 * @adapter: board private structure
 *
 * Free all receive software resources
 **/
static void ixgbevf_free_all_rx_resources(struct ixgbevf_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_rx_queues; i++)
                if (adapter->rx_ring[i].desc)
                        ixgbevf_free_rx_resources(adapter,
                                                  &adapter->rx_ring[i]);
}

static int ixgbevf_setup_queues(struct ixgbevf_adapter *adapter)
{
        struct ixgbe_hw *hw = &adapter->hw;
        struct ixgbevf_ring *rx_ring;
        unsigned int def_q = 0;
        unsigned int num_tcs = 0;
        unsigned int num_rx_queues = 1;
        int err, i;

        spin_lock_bh(&adapter->mbx_lock);

        /* fetch queue configuration from the PF */
        err = ixgbevf_get_queues(hw, &num_tcs, &def_q);

        spin_unlock_bh(&adapter->mbx_lock);

        if (err)
                return err;

        if (num_tcs > 1) {
                /* update default Tx ring register index */
                adapter->tx_ring[0].reg_idx = def_q;

                /* we need as many queues as traffic classes */
                num_rx_queues = num_tcs;
        }

        /* nothing to do if we have the correct number of queues */
        if (adapter->num_rx_queues == num_rx_queues)
                return 0;

        /* allocate new rings */
        rx_ring = kcalloc(num_rx_queues,
                          sizeof(struct ixgbevf_ring), GFP_KERNEL);
        if (!rx_ring)
                return -ENOMEM;

        /* setup ring fields */
        for (i = 0; i < num_rx_queues; i++) {
                rx_ring[i].count = adapter->rx_ring_count;
                rx_ring[i].queue_index = i;
                rx_ring[i].reg_idx = i;
                rx_ring[i].dev = &adapter->pdev->dev;
                rx_ring[i].netdev = adapter->netdev;
        }

        /* free the existing ring and queues */
        adapter->num_rx_queues = 0;
        kfree(adapter->rx_ring);

        /* move new rings into position on the adapter struct */
        adapter->rx_ring = rx_ring;
        adapter->num_rx_queues = num_rx_queues;

        return 0;
}

/**
 * ixgbevf_open - Called when a network interface is made active
 * @netdev: network interface device structure
 *
 * Returns 0 on success, negative value on failure
 *
 * The open entry point is called when a network interface is made
 * active by the system (IFF_UP).  At this point all resources needed
 * for transmit and receive operations are allocated, the interrupt
 * handler is registered with the OS, the watchdog timer is started,
 * and the stack is notified that the interface is ready.
 **/
static int ixgbevf_open(struct net_device *netdev)
{
        struct ixgbevf_adapter *adapter = netdev_priv(netdev);
        struct ixgbe_hw *hw = &adapter->hw;
        int err;

        /* A previous failure to open the device because of a lack of
         * available MSIX vector resources may have reset the number
         * of msix vectors variable to zero.  The only way to recover
         * is to unload/reload the driver and hope that the system has
         * been able to recover some MSIX vector resources.
         */
        if (!adapter->num_msix_vectors)
                return -ENOMEM;

        /* disallow open during test */
        if (test_bit(__IXGBEVF_TESTING, &adapter->state))
                return -EBUSY;

        if (hw->adapter_stopped) {
                ixgbevf_reset(adapter);
                /* if adapter is still stopped then PF isn't up and
                 * the vf can't start. */
                if (hw->adapter_stopped) {
                        err = IXGBE_ERR_MBX;
                        pr_err("Unable to start - perhaps the PF Driver isn't "
                               "up yet\n");
                        goto err_setup_reset;
                }
        }

        ixgbevf_negotiate_api(adapter);

        /* setup queue reg_idx and Rx queue count */
        err = ixgbevf_setup_queues(adapter);
        if (err)
                goto err_setup_queues;

        /* allocate transmit descriptors */
        err = ixgbevf_setup_all_tx_resources(adapter);
        if (err)
                goto err_setup_tx;

        /* allocate receive descriptors */
        err = ixgbevf_setup_all_rx_resources(adapter);
        if (err)
                goto err_setup_rx;

        ixgbevf_configure(adapter);

        /*
         * Map the Tx/Rx rings to the vectors we were allotted.
         * if request_irq will be called in this function map_rings
         * must be called *before* up_complete
         */
        ixgbevf_map_rings_to_vectors(adapter);

        ixgbevf_up_complete(adapter);

        /* clear any pending interrupts, may auto mask */
        IXGBE_READ_REG(hw, IXGBE_VTEICR);
        err = ixgbevf_request_irq(adapter);
        if (err)
                goto err_req_irq;

        ixgbevf_irq_enable(adapter);

        return 0;

err_req_irq:
        ixgbevf_down(adapter);
err_setup_rx:
        ixgbevf_free_all_rx_resources(adapter);
err_setup_tx:
        ixgbevf_free_all_tx_resources(adapter);
err_setup_queues:
        ixgbevf_reset(adapter);

err_setup_reset:

        return err;
}

/**
 * ixgbevf_close - Disables a network interface
 * @netdev: network interface device structure
 *
 * Returns 0, this is not allowed to fail
 *
 * The close entry point is called when an interface is de-activated
 * by the OS.  The hardware is still under the drivers control, but
 * needs to be disabled.  A global MAC reset is issued to stop the
 * hardware, and all transmit and receive resources are freed.
 **/
static int ixgbevf_close(struct net_device *netdev)
{
        struct ixgbevf_adapter *adapter = netdev_priv(netdev);

        ixgbevf_down(adapter);
        ixgbevf_free_irq(adapter);

        ixgbevf_free_all_tx_resources(adapter);
        ixgbevf_free_all_rx_resources(adapter);

        return 0;
}

static void ixgbevf_tx_ctxtdesc(struct ixgbevf_ring *tx_ring,
                                u32 vlan_macip_lens, u32 type_tucmd,
                                u32 mss_l4len_idx)
{
        struct ixgbe_adv_tx_context_desc *context_desc;
        u16 i = tx_ring->next_to_use;

        context_desc = IXGBEVF_TX_CTXTDESC(tx_ring, i);

        i++;
        tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;

        /* set bits to identify this as an advanced context descriptor */
        type_tucmd |= IXGBE_TXD_CMD_DEXT | IXGBE_ADVTXD_DTYP_CTXT;

        context_desc->vlan_macip_lens   = cpu_to_le32(vlan_macip_lens);
        context_desc->seqnum_seed       = 0;
        context_desc->type_tucmd_mlhl   = cpu_to_le32(type_tucmd);
        context_desc->mss_l4len_idx     = cpu_to_le32(mss_l4len_idx);
}

static int ixgbevf_tso(struct ixgbevf_ring *tx_ring,
                       struct sk_buff *skb, u32 tx_flags, u8 *hdr_len)
{
        u32 vlan_macip_lens, type_tucmd;
        u32 mss_l4len_idx, l4len;

        if (!skb_is_gso(skb))
                return 0;

        if (skb_header_cloned(skb)) {
                int err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
                if (err)
                        return err;
        }

        /* ADV DTYP TUCMD MKRLOC/ISCSIHEDLEN */
        type_tucmd = IXGBE_ADVTXD_TUCMD_L4T_TCP;

        if (skb->protocol == htons(ETH_P_IP)) {
                struct iphdr *iph = ip_hdr(skb);
                iph->tot_len = 0;
                iph->check = 0;
                tcp_hdr(skb)->check = ~csum_tcpudp_magic(iph->saddr,
                                                         iph->daddr, 0,
                                                         IPPROTO_TCP,
                                                         0);
                type_tucmd |= IXGBE_ADVTXD_TUCMD_IPV4;
        } else if (skb_is_gso_v6(skb)) {
                ipv6_hdr(skb)->payload_len = 0;
                tcp_hdr(skb)->check =
                    ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
                                     &ipv6_hdr(skb)->daddr,
                                     0, IPPROTO_TCP, 0);
        }

        /* compute header lengths */
        l4len = tcp_hdrlen(skb);
        *hdr_len += l4len;
        *hdr_len = skb_transport_offset(skb) + l4len;

        /* mss_l4len_id: use 1 as index for TSO */
        mss_l4len_idx = l4len << IXGBE_ADVTXD_L4LEN_SHIFT;
        mss_l4len_idx |= skb_shinfo(skb)->gso_size << IXGBE_ADVTXD_MSS_SHIFT;
        mss_l4len_idx |= 1 << IXGBE_ADVTXD_IDX_SHIFT;

        /* vlan_macip_lens: HEADLEN, MACLEN, VLAN tag */
        vlan_macip_lens = skb_network_header_len(skb);
        vlan_macip_lens |= skb_network_offset(skb) << IXGBE_ADVTXD_MACLEN_SHIFT;
        vlan_macip_lens |= tx_flags & IXGBE_TX_FLAGS_VLAN_MASK;

        ixgbevf_tx_ctxtdesc(tx_ring, vlan_macip_lens,
                            type_tucmd, mss_l4len_idx);

        return 1;
}

static bool ixgbevf_tx_csum(struct ixgbevf_ring *tx_ring,
                            struct sk_buff *skb, u32 tx_flags)
{
        u32 vlan_macip_lens = 0;
        u32 mss_l4len_idx = 0;
        u32 type_tucmd = 0;

        if (skb->ip_summed == CHECKSUM_PARTIAL) {
                u8 l4_hdr = 0;
                switch (skb->protocol) {
                case __constant_htons(ETH_P_IP):
                        vlan_macip_lens |= skb_network_header_len(skb);
                        type_tucmd |= IXGBE_ADVTXD_TUCMD_IPV4;
                        l4_hdr = ip_hdr(skb)->protocol;
                        break;
                case __constant_htons(ETH_P_IPV6):
                        vlan_macip_lens |= skb_network_header_len(skb);
                        l4_hdr = ipv6_hdr(skb)->nexthdr;
                        break;
                default:
                        if (unlikely(net_ratelimit())) {
                                dev_warn(tx_ring->dev,
                                 "partial checksum but proto=%x!\n",
                                 skb->protocol);
                        }
                        break;
                }

                switch (l4_hdr) {
                case IPPROTO_TCP:
                        type_tucmd |= IXGBE_ADVTXD_TUCMD_L4T_TCP;
                        mss_l4len_idx = tcp_hdrlen(skb) <<
                                        IXGBE_ADVTXD_L4LEN_SHIFT;
                        break;
                case IPPROTO_SCTP:
                        type_tucmd |= IXGBE_ADVTXD_TUCMD_L4T_SCTP;
                        mss_l4len_idx = sizeof(struct sctphdr) <<
                                        IXGBE_ADVTXD_L4LEN_SHIFT;
                        break;
                case IPPROTO_UDP:
                        mss_l4len_idx = sizeof(struct udphdr) <<
                                        IXGBE_ADVTXD_L4LEN_SHIFT;
                        break;
                default:
                        if (unlikely(net_ratelimit())) {
                                dev_warn(tx_ring->dev,
                                 "partial checksum but l4 proto=%x!\n",
                                 l4_hdr);
                        }
                        break;
                }
        }

        /* vlan_macip_lens: MACLEN, VLAN tag */
        vlan_macip_lens |= skb_network_offset(skb) << IXGBE_ADVTXD_MACLEN_SHIFT;
        vlan_macip_lens |= tx_flags & IXGBE_TX_FLAGS_VLAN_MASK;

        ixgbevf_tx_ctxtdesc(tx_ring, vlan_macip_lens,
                            type_tucmd, mss_l4len_idx);

        return (skb->ip_summed == CHECKSUM_PARTIAL);
}

static int ixgbevf_tx_map(struct ixgbevf_ring *tx_ring,
                          struct sk_buff *skb, u32 tx_flags)
{
        struct ixgbevf_tx_buffer *tx_buffer_info;
        unsigned int len;
        unsigned int total = skb->len;
        unsigned int offset = 0, size;
        int count = 0;
        unsigned int nr_frags = skb_shinfo(skb)->nr_frags;
        unsigned int f;
        int i;

        i = tx_ring->next_to_use;

        len = min(skb_headlen(skb), total);
        while (len) {
                tx_buffer_info = &tx_ring->tx_buffer_info[i];
                size = min(len, (unsigned int)IXGBE_MAX_DATA_PER_TXD);

                tx_buffer_info->length = size;
                tx_buffer_info->mapped_as_page = false;
                tx_buffer_info->dma = dma_map_single(tx_ring->dev,
                                                     skb->data + offset,
                                                     size, DMA_TO_DEVICE);
                if (dma_mapping_error(tx_ring->dev, tx_buffer_info->dma))
                        goto dma_error;

                len -= size;
                total -= size;
                offset += size;
                count++;
                i++;
                if (i == tx_ring->count)
                        i = 0;
        }

        for (f = 0; f < nr_frags; f++) {
                const struct skb_frag_struct *frag;

                frag = &skb_shinfo(skb)->frags[f];
                len = min((unsigned int)skb_frag_size(frag), total);
                offset = 0;

                while (len) {
                        tx_buffer_info = &tx_ring->tx_buffer_info[i];
                        size = min(len, (unsigned int)IXGBE_MAX_DATA_PER_TXD);

                        tx_buffer_info->length = size;
                        tx_buffer_info->dma =
                                skb_frag_dma_map(tx_ring->dev, frag,
                                                 offset, size, DMA_TO_DEVICE);
                        if (dma_mapping_error(tx_ring->dev,
                                              tx_buffer_info->dma))
                                goto dma_error;
                        tx_buffer_info->mapped_as_page = true;

                        len -= size;
                        total -= size;
                        offset += size;
                        count++;
                        i++;
                        if (i == tx_ring->count)
                                i = 0;
                }
                if (total == 0)
                        break;
        }

        if (i == 0)
                i = tx_ring->count - 1;
        else
                i = i - 1;
        tx_ring->tx_buffer_info[i].skb = skb;

        return count;

dma_error:
        dev_err(tx_ring->dev, "TX DMA map failed\n");

        /* clear timestamp and dma mappings for failed tx_buffer_info map */
        tx_buffer_info->dma = 0;
        count--;

        /* clear timestamp and dma mappings for remaining portion of packet */
        while (count >= 0) {
                count--;
                i--;
                if (i < 0)
                        i += tx_ring->count;
                tx_buffer_info = &tx_ring->tx_buffer_info[i];
                ixgbevf_unmap_and_free_tx_resource(tx_ring, tx_buffer_info);
        }

        return count;
}

static void ixgbevf_tx_queue(struct ixgbevf_ring *tx_ring, int tx_flags,
                             int count, unsigned int first, u32 paylen,
                             u8 hdr_len)
{
        union ixgbe_adv_tx_desc *tx_desc = NULL;
        struct ixgbevf_tx_buffer *tx_buffer_info;
        u32 olinfo_status = 0, cmd_type_len = 0;
        unsigned int i;

        u32 txd_cmd = IXGBE_TXD_CMD_EOP | IXGBE_TXD_CMD_RS | IXGBE_TXD_CMD_IFCS;

        cmd_type_len |= IXGBE_ADVTXD_DTYP_DATA;

        cmd_type_len |= IXGBE_ADVTXD_DCMD_IFCS | IXGBE_ADVTXD_DCMD_DEXT;

        if (tx_flags & IXGBE_TX_FLAGS_VLAN)
                cmd_type_len |= IXGBE_ADVTXD_DCMD_VLE;

        if (tx_flags & IXGBE_TX_FLAGS_CSUM)
                olinfo_status |= IXGBE_ADVTXD_POPTS_TXSM;

        if (tx_flags & IXGBE_TX_FLAGS_TSO) {
                cmd_type_len |= IXGBE_ADVTXD_DCMD_TSE;

                /* use index 1 context for tso */
                olinfo_status |= (1 << IXGBE_ADVTXD_IDX_SHIFT);
                if (tx_flags & IXGBE_TX_FLAGS_IPV4)
                        olinfo_status |= IXGBE_ADVTXD_POPTS_IXSM;
        }

        /*
         * Check Context must be set if Tx switch is enabled, which it
         * always is for case where virtual functions are running
         */
        olinfo_status |= IXGBE_ADVTXD_CC;

        olinfo_status |= ((paylen - hdr_len) << IXGBE_ADVTXD_PAYLEN_SHIFT);

        i = tx_ring->next_to_use;
        while (count--) {
                tx_buffer_info = &tx_ring->tx_buffer_info[i];
                tx_desc = IXGBEVF_TX_DESC(tx_ring, i);
                tx_desc->read.buffer_addr = cpu_to_le64(tx_buffer_info->dma);
                tx_desc->read.cmd_type_len =
                        cpu_to_le32(cmd_type_len | tx_buffer_info->length);
                tx_desc->read.olinfo_status = cpu_to_le32(olinfo_status);
                i++;
                if (i == tx_ring->count)
                        i = 0;
        }

        tx_desc->read.cmd_type_len |= cpu_to_le32(txd_cmd);

        tx_ring->tx_buffer_info[first].time_stamp = jiffies;

        /* Force memory writes to complete before letting h/w
         * know there are new descriptors to fetch.  (Only
         * applicable for weak-ordered memory model archs,
         * such as IA-64).
         */
        wmb();

        tx_ring->tx_buffer_info[first].next_to_watch = tx_desc;
        tx_ring->next_to_use = i;
}