/*
 * Copyright 2008-2010 Cisco Systems, Inc.  All rights reserved.
 * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
 *
 * This program is free software; you may redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/pci.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/if.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/tcp.h>
#include <linux/rtnetlink.h>
#include <linux/prefetch.h>
#include <net/ip6_checksum.h>
#include <linux/ktime.h>
#include <linux/numa.h>
#ifdef CONFIG_RFS_ACCEL
#include <linux/cpu_rmap.h>
#endif
#include <linux/crash_dump.h>
#include <net/busy_poll.h>
#include <net/vxlan.h>

#include "cq_enet_desc.h"
#include "vnic_dev.h"
#include "vnic_intr.h"
#include "vnic_stats.h"
#include "vnic_vic.h"
#include "enic_res.h"
#include "enic.h"
#include "enic_dev.h"
#include "enic_pp.h"
#include "enic_clsf.h"

#define ENIC_NOTIFY_TIMER_PERIOD        (2 * HZ)
#define WQ_ENET_MAX_DESC_LEN            (1 << WQ_ENET_LEN_BITS)
#define MAX_TSO                         (1 << 16)
#define ENIC_DESC_MAX_SPLITS            (MAX_TSO / WQ_ENET_MAX_DESC_LEN + 1)

#define PCI_DEVICE_ID_CISCO_VIC_ENET         0x0043  /* ethernet vnic */
#define PCI_DEVICE_ID_CISCO_VIC_ENET_DYN     0x0044  /* enet dynamic vnic */
#define PCI_DEVICE_ID_CISCO_VIC_ENET_VF      0x0071  /* enet SRIOV VF */

#define RX_COPYBREAK_DEFAULT            256

/* Supported devices */
static const struct pci_device_id enic_id_table[] = {
        { PCI_VDEVICE(CISCO, PCI_DEVICE_ID_CISCO_VIC_ENET) },
        { PCI_VDEVICE(CISCO, PCI_DEVICE_ID_CISCO_VIC_ENET_DYN) },
        { PCI_VDEVICE(CISCO, PCI_DEVICE_ID_CISCO_VIC_ENET_VF) },
        { 0, }  /* end of table */
};

MODULE_DESCRIPTION(DRV_DESCRIPTION);
MODULE_AUTHOR("Scott Feldman <scofeldm@cisco.com>");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, enic_id_table);

#define ENIC_LARGE_PKT_THRESHOLD                1000
#define ENIC_MAX_COALESCE_TIMERS                10
/*  Interrupt moderation table, which will be used to decide the
 *  coalescing timer values
 *  {rx_rate in Mbps, mapping percentage of the range}
 */
static struct enic_intr_mod_table mod_table[ENIC_MAX_COALESCE_TIMERS + 1] = {
        {4000,  0},
        {4400, 10},
        {5060, 20},
        {5230, 30},
        {5540, 40},
        {5820, 50},
        {6120, 60},
        {6435, 70},
        {6745, 80},
        {7000, 90},
        {0xFFFFFFFF, 100}
};

/* This table helps the driver to pick different ranges for rx coalescing
 * timer depending on the link speed.
 */
static struct enic_intr_mod_range mod_range[ENIC_MAX_LINK_SPEEDS] = {
        {0,  0}, /* 0  - 4  Gbps */
        {0,  3}, /* 4  - 10 Gbps */
        {3,  6}, /* 10 - 40 Gbps */
};

static void enic_init_affinity_hint(struct enic *enic)
{
        int numa_node = dev_to_node(&enic->pdev->dev);
        int i;

        for (i = 0; i < enic->intr_count; i++) {
                if (enic_is_err_intr(enic, i) || enic_is_notify_intr(enic, i) ||
                    (cpumask_available(enic->msix[i].affinity_mask) &&
                     !cpumask_empty(enic->msix[i].affinity_mask)))
                        continue;
                if (zalloc_cpumask_var(&enic->msix[i].affinity_mask,
                                       GFP_KERNEL))
                        cpumask_set_cpu(cpumask_local_spread(i, numa_node),
                                        enic->msix[i].affinity_mask);
        }
}

static void enic_free_affinity_hint(struct enic *enic)
{
        int i;

        for (i = 0; i < enic->intr_count; i++) {
                if (enic_is_err_intr(enic, i) || enic_is_notify_intr(enic, i))
                        continue;
                free_cpumask_var(enic->msix[i].affinity_mask);
        }
}

static void enic_set_affinity_hint(struct enic *enic)
{
        int i;
        int err;

        for (i = 0; i < enic->intr_count; i++) {
                if (enic_is_err_intr(enic, i)           ||
                    enic_is_notify_intr(enic, i)        ||
                    !cpumask_available(enic->msix[i].affinity_mask) ||
                    cpumask_empty(enic->msix[i].affinity_mask))
                        continue;
                err = irq_set_affinity_hint(enic->msix_entry[i].vector,
                                            enic->msix[i].affinity_mask);
                if (err)
                        netdev_warn(enic->netdev, "irq_set_affinity_hint failed, err %d\n",
                                    err);
        }

        for (i = 0; i < enic->wq_count; i++) {
                int wq_intr = enic_msix_wq_intr(enic, i);

                if (cpumask_available(enic->msix[wq_intr].affinity_mask) &&
                    !cpumask_empty(enic->msix[wq_intr].affinity_mask))
                        netif_set_xps_queue(enic->netdev,
                                            enic->msix[wq_intr].affinity_mask,
                                            i);
        }
}

static void enic_unset_affinity_hint(struct enic *enic)
{
        int i;

        for (i = 0; i < enic->intr_count; i++)
                irq_set_affinity_hint(enic->msix_entry[i].vector, NULL);
}

static int enic_udp_tunnel_set_port(struct net_device *netdev,
                                    unsigned int table, unsigned int entry,
                                    struct udp_tunnel_info *ti)
{
        struct enic *enic = netdev_priv(netdev);
        int err;

        spin_lock_bh(&enic->devcmd_lock);

        err = vnic_dev_overlay_offload_cfg(enic->vdev,
                                           OVERLAY_CFG_VXLAN_PORT_UPDATE,
                                           ntohs(ti->port));
        if (err)
                goto error;

        err = vnic_dev_overlay_offload_ctrl(enic->vdev, OVERLAY_FEATURE_VXLAN,
                                            enic->vxlan.patch_level);
        if (err)
                goto error;

        enic->vxlan.vxlan_udp_port_number = ntohs(ti->port);
error:
        spin_unlock_bh(&enic->devcmd_lock);

        return err;
}

static int enic_udp_tunnel_unset_port(struct net_device *netdev,
                                      unsigned int table, unsigned int entry,
                                      struct udp_tunnel_info *ti)
{
        struct enic *enic = netdev_priv(netdev);
        int err;

        spin_lock_bh(&enic->devcmd_lock);

        err = vnic_dev_overlay_offload_ctrl(enic->vdev, OVERLAY_FEATURE_VXLAN,
                                            OVERLAY_OFFLOAD_DISABLE);
        if (err)
                goto unlock;

        enic->vxlan.vxlan_udp_port_number = 0;

unlock:
        spin_unlock_bh(&enic->devcmd_lock);

        return err;
}

static const struct udp_tunnel_nic_info enic_udp_tunnels = {
        .set_port       = enic_udp_tunnel_set_port,
        .unset_port     = enic_udp_tunnel_unset_port,
        .tables         = {
                { .n_entries = 1, .tunnel_types = UDP_TUNNEL_TYPE_VXLAN, },
        },
}, enic_udp_tunnels_v4 = {
        .set_port       = enic_udp_tunnel_set_port,
        .unset_port     = enic_udp_tunnel_unset_port,
        .flags          = UDP_TUNNEL_NIC_INFO_IPV4_ONLY,
        .tables         = {
                { .n_entries = 1, .tunnel_types = UDP_TUNNEL_TYPE_VXLAN, },
        },
};

static netdev_features_t enic_features_check(struct sk_buff *skb,
                                             struct net_device *dev,
                                             netdev_features_t features)
{
        const struct ethhdr *eth = (struct ethhdr *)skb_inner_mac_header(skb);
        struct enic *enic = netdev_priv(dev);
        struct udphdr *udph;
        u16 port = 0;
        u8 proto;

        if (!skb->encapsulation)
                return features;

        features = vxlan_features_check(skb, features);

        switch (vlan_get_protocol(skb)) {
        case htons(ETH_P_IPV6):
                if (!(enic->vxlan.flags & ENIC_VXLAN_OUTER_IPV6))
                        goto out;
                proto = ipv6_hdr(skb)->nexthdr;
                break;
        case htons(ETH_P_IP):
                proto = ip_hdr(skb)->protocol;
                break;
        default:
                goto out;
        }

        switch (eth->h_proto) {
        case ntohs(ETH_P_IPV6):
                if (!(enic->vxlan.flags & ENIC_VXLAN_INNER_IPV6))
                        goto out;
                fallthrough;
        case ntohs(ETH_P_IP):
                break;
        default:
                goto out;
        }


        if (proto == IPPROTO_UDP) {
                udph = udp_hdr(skb);
                port = be16_to_cpu(udph->dest);
        }

        /* HW supports offload of only one UDP port. Remove CSUM and GSO MASK
         * for other UDP port tunnels
         */
        if (port  != enic->vxlan.vxlan_udp_port_number)
                goto out;

        return features;

out:
        return features & ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
}

int enic_is_dynamic(struct enic *enic)
{
        return enic->pdev->device == PCI_DEVICE_ID_CISCO_VIC_ENET_DYN;
}

int enic_sriov_enabled(struct enic *enic)
{
        return (enic->priv_flags & ENIC_SRIOV_ENABLED) ? 1 : 0;
}

static int enic_is_sriov_vf(struct enic *enic)
{
        return enic->pdev->device == PCI_DEVICE_ID_CISCO_VIC_ENET_VF;
}

int enic_is_valid_vf(struct enic *enic, int vf)
{
#ifdef CONFIG_PCI_IOV
        return vf >= 0 && vf < enic->num_vfs;
#else
        return 0;
#endif
}

static void enic_free_wq_buf(struct vnic_wq *wq, struct vnic_wq_buf *buf)
{
        struct enic *enic = vnic_dev_priv(wq->vdev);

        if (buf->sop)
                dma_unmap_single(&enic->pdev->dev, buf->dma_addr, buf->len,
                                 DMA_TO_DEVICE);
        else
                dma_unmap_page(&enic->pdev->dev, buf->dma_addr, buf->len,
                               DMA_TO_DEVICE);

        if (buf->os_buf)
                dev_kfree_skb_any(buf->os_buf);
}

static void enic_wq_free_buf(struct vnic_wq *wq,
        struct cq_desc *cq_desc, struct vnic_wq_buf *buf, void *opaque)
{
        enic_free_wq_buf(wq, buf);
}

static int enic_wq_service(struct vnic_dev *vdev, struct cq_desc *cq_desc,
        u8 type, u16 q_number, u16 completed_index, void *opaque)
{
        struct enic *enic = vnic_dev_priv(vdev);

        spin_lock(&enic->wq_lock[q_number]);

        vnic_wq_service(&enic->wq[q_number], cq_desc,
                completed_index, enic_wq_free_buf,
                opaque);

        if (netif_tx_queue_stopped(netdev_get_tx_queue(enic->netdev, q_number)) &&
            vnic_wq_desc_avail(&enic->wq[q_number]) >=
            (MAX_SKB_FRAGS + ENIC_DESC_MAX_SPLITS))
                netif_wake_subqueue(enic->netdev, q_number);

        spin_unlock(&enic->wq_lock[q_number]);

        return 0;
}

static bool enic_log_q_error(struct enic *enic)
{
        unsigned int i;
        u32 error_status;
        bool err = false;

        for (i = 0; i < enic->wq_count; i++) {
                error_status = vnic_wq_error_status(&enic->wq[i]);
                err |= error_status;
                if (error_status)
                        netdev_err(enic->netdev, "WQ[%d] error_status %d\n",
                                i, error_status);
        }

        for (i = 0; i < enic->rq_count; i++) {
                error_status = vnic_rq_error_status(&enic->rq[i]);
                err |= error_status;
                if (error_status)
                        netdev_err(enic->netdev, "RQ[%d] error_status %d\n",
                                i, error_status);
        }

        return err;
}

static void enic_msglvl_check(struct enic *enic)
{
        u32 msg_enable = vnic_dev_msg_lvl(enic->vdev);

        if (msg_enable != enic->msg_enable) {
                netdev_info(enic->netdev, "msg lvl changed from 0x%x to 0x%x\n",
                        enic->msg_enable, msg_enable);
                enic->msg_enable = msg_enable;
        }
}

static void enic_mtu_check(struct enic *enic)
{
        u32 mtu = vnic_dev_mtu(enic->vdev);
        struct net_device *netdev = enic->netdev;

        if (mtu && mtu != enic->port_mtu) {
                enic->port_mtu = mtu;
                if (enic_is_dynamic(enic) || enic_is_sriov_vf(enic)) {
                        mtu = max_t(int, ENIC_MIN_MTU,
                                min_t(int, ENIC_MAX_MTU, mtu));
                        if (mtu != netdev->mtu)
                                schedule_work(&enic->change_mtu_work);
                } else {
                        if (mtu < netdev->mtu)
                                netdev_warn(netdev,
                                        "interface MTU (%d) set higher "
                                        "than switch port MTU (%d)\n",
                                        netdev->mtu, mtu);
                }
        }
}

static void enic_link_check(struct enic *enic)
{
        int link_status = vnic_dev_link_status(enic->vdev);
        int carrier_ok = netif_carrier_ok(enic->netdev);

        if (link_status && !carrier_ok) {
                netdev_info(enic->netdev, "Link UP\n");
                netif_carrier_on(enic->netdev);
        } else if (!link_status && carrier_ok) {
                netdev_info(enic->netdev, "Link DOWN\n");
                netif_carrier_off(enic->netdev);
        }
}

static void enic_notify_check(struct enic *enic)
{
        enic_msglvl_check(enic);
        enic_mtu_check(enic);
        enic_link_check(enic);
}

#define ENIC_TEST_INTR(pba, i) (pba & (1 << i))

static irqreturn_t enic_isr_legacy(int irq, void *data)
{
        struct net_device *netdev = data;
        struct enic *enic = netdev_priv(netdev);
        unsigned int io_intr = enic_legacy_io_intr();
        unsigned int err_intr = enic_legacy_err_intr();
        unsigned int notify_intr = enic_legacy_notify_intr();
        u32 pba;

        vnic_intr_mask(&enic->intr[io_intr]);

        pba = vnic_intr_legacy_pba(enic->legacy_pba);
        if (!pba) {
                vnic_intr_unmask(&enic->intr[io_intr]);
                return IRQ_NONE;        /* not our interrupt */
        }

        if (ENIC_TEST_INTR(pba, notify_intr)) {
                enic_notify_check(enic);
                vnic_intr_return_all_credits(&enic->intr[notify_intr]);
        }

        if (ENIC_TEST_INTR(pba, err_intr)) {
                vnic_intr_return_all_credits(&enic->intr[err_intr]);
                enic_log_q_error(enic);
                /* schedule recovery from WQ/RQ error */
                schedule_work(&enic->reset);
                return IRQ_HANDLED;
        }

        if (ENIC_TEST_INTR(pba, io_intr))
                napi_schedule_irqoff(&enic->napi[0]);
        else
                vnic_intr_unmask(&enic->intr[io_intr]);

        return IRQ_HANDLED;
}

static irqreturn_t enic_isr_msi(int irq, void *data)
{
        struct enic *enic = data;

        /* With MSI, there is no sharing of interrupts, so this is
         * our interrupt and there is no need to ack it.  The device
         * is not providing per-vector masking, so the OS will not
         * write to PCI config space to mask/unmask the interrupt.
         * We're using mask_on_assertion for MSI, so the device
         * automatically masks the interrupt when the interrupt is
         * generated.  Later, when exiting polling, the interrupt
         * will be unmasked (see enic_poll).
         *
         * Also, the device uses the same PCIe Traffic Class (TC)
         * for Memory Write data and MSI, so there are no ordering
         * issues; the MSI will always arrive at the Root Complex
         * _after_ corresponding Memory Writes (i.e. descriptor
         * writes).
         */

        napi_schedule_irqoff(&enic->napi[0]);

        return IRQ_HANDLED;
}

static irqreturn_t enic_isr_msix(int irq, void *data)
{
        struct napi_struct *napi = data;

        napi_schedule_irqoff(napi);

        return IRQ_HANDLED;
}

static irqreturn_t enic_isr_msix_err(int irq, void *data)
{
        struct enic *enic = data;
        unsigned int intr = enic_msix_err_intr(enic);

        vnic_intr_return_all_credits(&enic->intr[intr]);

        if (enic_log_q_error(enic))
                /* schedule recovery from WQ/RQ error */
                schedule_work(&enic->reset);

        return IRQ_HANDLED;
}

static irqreturn_t enic_isr_msix_notify(int irq, void *data)
{
        struct enic *enic = data;
        unsigned int intr = enic_msix_notify_intr(enic);

        enic_notify_check(enic);
        vnic_intr_return_all_credits(&enic->intr[intr]);

        return IRQ_HANDLED;
}

static int enic_queue_wq_skb_cont(struct enic *enic, struct vnic_wq *wq,
                                  struct sk_buff *skb, unsigned int len_left,
                                  int loopback)
{
        const skb_frag_t *frag;
        dma_addr_t dma_addr;

        /* Queue additional data fragments */
        for (frag = skb_shinfo(skb)->frags; len_left; frag++) {
                len_left -= skb_frag_size(frag);
                dma_addr = skb_frag_dma_map(&enic->pdev->dev, frag, 0,
                                            skb_frag_size(frag),
                                            DMA_TO_DEVICE);
                if (unlikely(enic_dma_map_check(enic, dma_addr)))
                        return -ENOMEM;
                enic_queue_wq_desc_cont(wq, skb, dma_addr, skb_frag_size(frag),
                                        (len_left == 0),        /* EOP? */
                                        loopback);
        }

        return 0;
}

static int enic_queue_wq_skb_vlan(struct enic *enic, struct vnic_wq *wq,
                                  struct sk_buff *skb, int vlan_tag_insert,
                                  unsigned int vlan_tag, int loopback)
{
        unsigned int head_len = skb_headlen(skb);
        unsigned int len_left = skb->len - head_len;
        int eop = (len_left == 0);
        dma_addr_t dma_addr;
        int err = 0;

        dma_addr = dma_map_single(&enic->pdev->dev, skb->data, head_len,
                                  DMA_TO_DEVICE);
        if (unlikely(enic_dma_map_check(enic, dma_addr)))
                return -ENOMEM;

        /* Queue the main skb fragment. The fragments are no larger
         * than max MTU(9000)+ETH_HDR_LEN(14) bytes, which is less
         * than WQ_ENET_MAX_DESC_LEN length. So only one descriptor
         * per fragment is queued.
         */
        enic_queue_wq_desc(wq, skb, dma_addr, head_len, vlan_tag_insert,
                           vlan_tag, eop, loopback);

        if (!eop)
                err = enic_queue_wq_skb_cont(enic, wq, skb, len_left, loopback);

        return err;
}

static int enic_queue_wq_skb_csum_l4(struct enic *enic, struct vnic_wq *wq,
                                     struct sk_buff *skb, int vlan_tag_insert,
                                     unsigned int vlan_tag, int loopback)
{
        unsigned int head_len = skb_headlen(skb);
        unsigned int len_left = skb->len - head_len;
        unsigned int hdr_len = skb_checksum_start_offset(skb);
        unsigned int csum_offset = hdr_len + skb->csum_offset;
        int eop = (len_left == 0);
        dma_addr_t dma_addr;
        int err = 0;

        dma_addr = dma_map_single(&enic->pdev->dev, skb->data, head_len,
                                  DMA_TO_DEVICE);
        if (unlikely(enic_dma_map_check(enic, dma_addr)))
                return -ENOMEM;

        /* Queue the main skb fragment. The fragments are no larger
         * than max MTU(9000)+ETH_HDR_LEN(14) bytes, which is less
         * than WQ_ENET_MAX_DESC_LEN length. So only one descriptor
         * per fragment is queued.
         */
        enic_queue_wq_desc_csum_l4(wq, skb, dma_addr, head_len, csum_offset,
                                   hdr_len, vlan_tag_insert, vlan_tag, eop,
                                   loopback);

        if (!eop)
                err = enic_queue_wq_skb_cont(enic, wq, skb, len_left, loopback);

        return err;
}

static void enic_preload_tcp_csum_encap(struct sk_buff *skb)
{
        const struct ethhdr *eth = (struct ethhdr *)skb_inner_mac_header(skb);

        switch (eth->h_proto) {
        case ntohs(ETH_P_IP):
                inner_ip_hdr(skb)->check = 0;
                inner_tcp_hdr(skb)->check =
                        ~csum_tcpudp_magic(inner_ip_hdr(skb)->saddr,
                                           inner_ip_hdr(skb)->daddr, 0,
                                           IPPROTO_TCP, 0);
                break;
        case ntohs(ETH_P_IPV6):
                inner_tcp_hdr(skb)->check =
                        ~csum_ipv6_magic(&inner_ipv6_hdr(skb)->saddr,
                                         &inner_ipv6_hdr(skb)->daddr, 0,
                                         IPPROTO_TCP, 0);
                break;
        default:
                WARN_ONCE(1, "Non ipv4/ipv6 inner pkt for encap offload");
                break;
        }
}

static void enic_preload_tcp_csum(struct sk_buff *skb)
{
        /* Preload TCP csum field with IP pseudo hdr calculated
         * with IP length set to zero.  HW will later add in length
         * to each TCP segment resulting from the TSO.
         */

        if (skb->protocol == cpu_to_be16(ETH_P_IP)) {
                ip_hdr(skb)->check = 0;
                tcp_hdr(skb)->check = ~csum_tcpudp_magic(ip_hdr(skb)->saddr,
                        ip_hdr(skb)->daddr, 0, IPPROTO_TCP, 0);
        } else if (skb->protocol == cpu_to_be16(ETH_P_IPV6)) {
                tcp_v6_gso_csum_prep(skb);
        }
}

static int enic_queue_wq_skb_tso(struct enic *enic, struct vnic_wq *wq,
                                 struct sk_buff *skb, unsigned int mss,
                                 int vlan_tag_insert, unsigned int vlan_tag,
                                 int loopback)
{
        unsigned int frag_len_left = skb_headlen(skb);
        unsigned int len_left = skb->len - frag_len_left;
        int eop = (len_left == 0);
        unsigned int offset = 0;
        unsigned int hdr_len;
        dma_addr_t dma_addr;
        unsigned int len;
        skb_frag_t *frag;

        if (skb->encapsulation) {
                hdr_len = skb_inner_transport_header(skb) - skb->data;
                hdr_len += inner_tcp_hdrlen(skb);
                enic_preload_tcp_csum_encap(skb);
        } else {
                hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
                enic_preload_tcp_csum(skb);
        }

        /* Queue WQ_ENET_MAX_DESC_LEN length descriptors
         * for the main skb fragment
         */
        while (frag_len_left) {
                len = min(frag_len_left, (unsigned int)WQ_ENET_MAX_DESC_LEN);
                dma_addr = dma_map_single(&enic->pdev->dev,
                                          skb->data + offset, len,
                                          DMA_TO_DEVICE);
                if (unlikely(enic_dma_map_check(enic, dma_addr)))
                        return -ENOMEM;
                enic_queue_wq_desc_tso(wq, skb, dma_addr, len, mss, hdr_len,
                                       vlan_tag_insert, vlan_tag,
                                       eop && (len == frag_len_left), loopback);
                frag_len_left -= len;
                offset += len;
        }

        if (eop)
                return 0;

        /* Queue WQ_ENET_MAX_DESC_LEN length descriptors
         * for additional data fragments
         */
        for (frag = skb_shinfo(skb)->frags; len_left; frag++) {
                len_left -= skb_frag_size(frag);
                frag_len_left = skb_frag_size(frag);
                offset = 0;

                while (frag_len_left) {
                        len = min(frag_len_left,
                                (unsigned int)WQ_ENET_MAX_DESC_LEN);
                        dma_addr = skb_frag_dma_map(&enic->pdev->dev, frag,
                                                    offset, len,
                                                    DMA_TO_DEVICE);
                        if (unlikely(enic_dma_map_check(enic, dma_addr)))
                                return -ENOMEM;
                        enic_queue_wq_desc_cont(wq, skb, dma_addr, len,
                                                (len_left == 0) &&
                                                 (len == frag_len_left),/*EOP*/
                                                loopback);
                        frag_len_left -= len;
                        offset += len;
                }
        }

        return 0;
}

static inline int enic_queue_wq_skb_encap(struct enic *enic, struct vnic_wq *wq,
                                          struct sk_buff *skb,
                                          int vlan_tag_insert,
                                          unsigned int vlan_tag, int loopback)
{
        unsigned int head_len = skb_headlen(skb);
        unsigned int len_left = skb->len - head_len;
        /* Hardware will overwrite the checksum fields, calculating from
         * scratch and ignoring the value placed by software.
         * Offload mode = 00
         * mss[2], mss[1], mss[0] bits are set
         */
        unsigned int mss_or_csum = 7;
        int eop = (len_left == 0);
        dma_addr_t dma_addr;
        int err = 0;

        dma_addr = dma_map_single(&enic->pdev->dev, skb->data, head_len,
                                  DMA_TO_DEVICE);
        if (unlikely(enic_dma_map_check(enic, dma_addr)))
                return -ENOMEM;

        enic_queue_wq_desc_ex(wq, skb, dma_addr, head_len, mss_or_csum, 0,
                              vlan_tag_insert, vlan_tag,
                              WQ_ENET_OFFLOAD_MODE_CSUM, eop, 1 /* SOP */, eop,
                              loopback);
        if (!eop)
                err = enic_queue_wq_skb_cont(enic, wq, skb, len_left, loopback);

        return err;
}

static inline int enic_queue_wq_skb(struct enic *enic,
        struct vnic_wq *wq, struct sk_buff *skb)
{
        unsigned int mss = skb_shinfo(skb)->gso_size;
        unsigned int vlan_tag = 0;
        int vlan_tag_insert = 0;
        int loopback = 0;
        int err;

        if (skb_vlan_tag_present(skb)) {
                /* VLAN tag from trunking driver */
                vlan_tag_insert = 1;
                vlan_tag = skb_vlan_tag_get(skb);
        } else if (enic->loop_enable) {
                vlan_tag = enic->loop_tag;
                loopback = 1;
        }

        if (mss)
                err = enic_queue_wq_skb_tso(enic, wq, skb, mss,
                                            vlan_tag_insert, vlan_tag,
                                            loopback);
        else if (skb->encapsulation)
                err = enic_queue_wq_skb_encap(enic, wq, skb, vlan_tag_insert,
                                              vlan_tag, loopback);
        else if (skb->ip_summed == CHECKSUM_PARTIAL)
                err = enic_queue_wq_skb_csum_l4(enic, wq, skb, vlan_tag_insert,
                                                vlan_tag, loopback);
        else
                err = enic_queue_wq_skb_vlan(enic, wq, skb, vlan_tag_insert,
                                             vlan_tag, loopback);
        if (unlikely(err)) {
                struct vnic_wq_buf *buf;

                buf = wq->to_use->prev;
                /* while not EOP of previous pkt && queue not empty.
                 * For all non EOP bufs, os_buf is NULL.
                 */
                while (!buf->os_buf && (buf->next != wq->to_clean)) {
                        enic_free_wq_buf(wq, buf);
                        wq->ring.desc_avail++;
                        buf = buf->prev;
                }
                wq->to_use = buf->next;
                dev_kfree_skb(skb);
        }
        return err;
}

/* netif_tx_lock held, process context with BHs disabled, or BH */
static netdev_tx_t enic_hard_start_xmit(struct sk_buff *skb,
        struct net_device *netdev)
{
        struct enic *enic = netdev_priv(netdev);
        struct vnic_wq *wq;
        unsigned int txq_map;
        struct netdev_queue *txq;

        if (skb->len <= 0) {
                dev_kfree_skb_any(skb);
                return NETDEV_TX_OK;
        }

        txq_map = skb_get_queue_mapping(skb) % enic->wq_count;
        wq = &enic->wq[txq_map];
        txq = netdev_get_tx_queue(netdev, txq_map);

        /* Non-TSO sends must fit within ENIC_NON_TSO_MAX_DESC descs,
         * which is very likely.  In the off chance it's going to take
         * more than * ENIC_NON_TSO_MAX_DESC, linearize the skb.
         */

        if (skb_shinfo(skb)->gso_size == 0 &&
            skb_shinfo(skb)->nr_frags + 1 > ENIC_NON_TSO_MAX_DESC &&
            skb_linearize(skb)) {
                dev_kfree_skb_any(skb);
                return NETDEV_TX_OK;
        }

        spin_lock(&enic->wq_lock[txq_map]);

        if (vnic_wq_desc_avail(wq) <
            skb_shinfo(skb)->nr_frags + ENIC_DESC_MAX_SPLITS) {
                netif_tx_stop_queue(txq);
                /* This is a hard error, log it */
                netdev_err(netdev, "BUG! Tx ring full when queue awake!\n");
                spin_unlock(&enic->wq_lock[txq_map]);
                return NETDEV_TX_BUSY;
        }

        if (enic_queue_wq_skb(enic, wq, skb))
                goto error;

        if (vnic_wq_desc_avail(wq) < MAX_SKB_FRAGS + ENIC_DESC_MAX_SPLITS)
                netif_tx_stop_queue(txq);
        skb_tx_timestamp(skb);
        if (!netdev_xmit_more() || netif_xmit_stopped(txq))
                vnic_wq_doorbell(wq);

error:
        spin_unlock(&enic->wq_lock[txq_map]);

        return NETDEV_TX_OK;
}

/* dev_base_lock rwlock held, nominally process context */
static void enic_get_stats(struct net_device *netdev,
                           struct rtnl_link_stats64 *net_stats)
{
        struct enic *enic = netdev_priv(netdev);
        struct vnic_stats *stats;
        int err;

        err = enic_dev_stats_dump(enic, &stats);
        /* return only when pci_zalloc_consistent fails in vnic_dev_stats_dump
         * For other failures, like devcmd failure, we return previously
         * recorded stats.
         */
        if (err == -ENOMEM)
                return;

        net_stats->tx_packets = stats->tx.tx_frames_ok;
        net_stats->tx_bytes = stats->tx.tx_bytes_ok;
        net_stats->tx_errors = stats->tx.tx_errors;
        net_stats->tx_dropped = stats->tx.tx_drops;

        net_stats->rx_packets = stats->rx.rx_frames_ok;
        net_stats->rx_bytes = stats->rx.rx_bytes_ok;
        net_stats->rx_errors = stats->rx.rx_errors;
        net_stats->multicast = stats->rx.rx_multicast_frames_ok;
        net_stats->rx_over_errors = enic->rq_truncated_pkts;
        net_stats->rx_crc_errors = enic->rq_bad_fcs;
        net_stats->rx_dropped = stats->rx.rx_no_bufs + stats->rx.rx_drop;
}

static int enic_mc_sync(struct net_device *netdev, const u8 *mc_addr)
{
        struct enic *enic = netdev_priv(netdev);

        if (enic->mc_count == ENIC_MULTICAST_PERFECT_FILTERS) {
                unsigned int mc_count = netdev_mc_count(netdev);

                netdev_warn(netdev, "Registering only %d out of %d multicast addresses\n",
                            ENIC_MULTICAST_PERFECT_FILTERS, mc_count);

                return -ENOSPC;
        }

        enic_dev_add_addr(enic, mc_addr);
        enic->mc_count++;

        return 0;
}

static int enic_mc_unsync(struct net_device *netdev, const u8 *mc_addr)
{
        struct enic *enic = netdev_priv(netdev);

        enic_dev_del_addr(enic, mc_addr);
        enic->mc_count--;

        return 0;
}

static int enic_uc_sync(struct net_device *netdev, const u8 *uc_addr)
{
        struct enic *enic = netdev_priv(netdev);

        if (enic->uc_count == ENIC_UNICAST_PERFECT_FILTERS) {
                unsigned int uc_count = netdev_uc_count(netdev);

                netdev_warn(netdev, "Registering only %d out of %d unicast addresses\n",
                            ENIC_UNICAST_PERFECT_FILTERS, uc_count);

                return -ENOSPC;
        }

        enic_dev_add_addr(enic, uc_addr);
        enic->uc_count++;

        return 0;
}

static int enic_uc_unsync(struct net_device *netdev, const u8 *uc_addr)
{
        struct enic *enic = netdev_priv(netdev);

        enic_dev_del_addr(enic, uc_addr);
        enic->uc_count--;

        return 0;
}

void enic_reset_addr_lists(struct enic *enic)
{
        struct net_device *netdev = enic->netdev;

        __dev_uc_unsync(netdev, NULL);
        __dev_mc_unsync(netdev, NULL);

        enic->mc_count = 0;
        enic->uc_count = 0;
        enic->flags = 0;
}

static int enic_set_mac_addr(struct net_device *netdev, char *addr)
{
        struct enic *enic = netdev_priv(netdev);

        if (enic_is_dynamic(enic) || enic_is_sriov_vf(enic)) {
                if (!is_valid_ether_addr(addr) && !is_zero_ether_addr(addr))
                        return -EADDRNOTAVAIL;
        } else {
                if (!is_valid_ether_addr(addr))
                        return -EADDRNOTAVAIL;
        }

        memcpy(netdev->dev_addr, addr, netdev->addr_len);

        return 0;
}

static int enic_set_mac_address_dynamic(struct net_device *netdev, void *p)
{
        struct enic *enic = netdev_priv(netdev);
        struct sockaddr *saddr = p;
        char *addr = saddr->sa_data;
        int err;

        if (netif_running(enic->netdev)) {

                err = enic_dev_del_station_addr(enic);
                if (err)
                        return err;
        }

        err = enic_set_mac_addr(netdev, addr);
        if (err)
                return err;

        if (netif_running(enic->netdev)) {
                err = enic_dev_add_station_addr(enic);
                if (err)
                        return err;
        }

        return err;
}

static int enic_set_mac_address(struct net_device *netdev, void *p)
{
        struct sockaddr *saddr = p;
        char *addr = saddr->sa_data;
        struct enic *enic = netdev_priv(netdev);
        int err;

        err = enic_dev_del_station_addr(enic);
        if (err)
                return err;

        err = enic_set_mac_addr(netdev, addr);
        if (err)
                return err;

        return enic_dev_add_station_addr(enic);
}

/* netif_tx_lock held, BHs disabled */
static void enic_set_rx_mode(struct net_device *netdev)
{
        struct enic *enic = netdev_priv(netdev);
        int directed = 1;
        int multicast = (netdev->flags & IFF_MULTICAST) ? 1 : 0;
        int broadcast = (netdev->flags & IFF_BROADCAST) ? 1 : 0;
        int promisc = (netdev->flags & IFF_PROMISC) ||
                netdev_uc_count(netdev) > ENIC_UNICAST_PERFECT_FILTERS;
        int allmulti = (netdev->flags & IFF_ALLMULTI) ||
                netdev_mc_count(netdev) > ENIC_MULTICAST_PERFECT_FILTERS;
        unsigned int flags = netdev->flags |
                (allmulti ? IFF_ALLMULTI : 0) |
                (promisc ? IFF_PROMISC : 0);

        if (enic->flags != flags) {
                enic->flags = flags;
                enic_dev_packet_filter(enic, directed,
                        multicast, broadcast, promisc, allmulti);
        }

        if (!promisc) {
                __dev_uc_sync(netdev, enic_uc_sync, enic_uc_unsync);
                if (!allmulti)
                        __dev_mc_sync(netdev, enic_mc_sync, enic_mc_unsync);
        }
}

/* netif_tx_lock held, BHs disabled */
static void enic_tx_timeout(struct net_device *netdev, unsigned int txqueue)
{
        struct enic *enic = netdev_priv(netdev);
        schedule_work(&enic->tx_hang_reset);
}

static int enic_set_vf_mac(struct net_device *netdev, int vf, u8 *mac)
{
        struct enic *enic = netdev_priv(netdev);
        struct enic_port_profile *pp;
        int err;

        ENIC_PP_BY_INDEX(enic, vf, pp, &err);
        if (err)
                return err;

        if (is_valid_ether_addr(mac) || is_zero_ether_addr(mac)) {
                if (vf == PORT_SELF_VF) {
                        memcpy(pp->vf_mac, mac, ETH_ALEN);
                        return 0;
                } else {
                        /*
                         * For sriov vf's set the mac in hw
                         */
                        ENIC_DEVCMD_PROXY_BY_INDEX(vf, err, enic,
                                vnic_dev_set_mac_addr, mac);
                        return enic_dev_status_to_errno(err);
                }
        } else
                return -EINVAL;
}

static int enic_set_vf_port(struct net_device *netdev, int vf,
        struct nlattr *port[])
{
        struct enic *enic = netdev_priv(netdev);
        struct enic_port_profile prev_pp;
        struct enic_port_profile *pp;
        int err = 0, restore_pp = 1;

        ENIC_PP_BY_INDEX(enic, vf, pp, &err);
        if (err)
                return err;

        if (!port[IFLA_PORT_REQUEST])
                return -EOPNOTSUPP;

        memcpy(&prev_pp, pp, sizeof(*enic->pp));
        memset(pp, 0, sizeof(*enic->pp));

        pp->set |= ENIC_SET_REQUEST;
        pp->request = nla_get_u8(port[IFLA_PORT_REQUEST]);

        if (port[IFLA_PORT_PROFILE]) {
                pp->set |= ENIC_SET_NAME;
                memcpy(pp->name, nla_data(port[IFLA_PORT_PROFILE]),
                        PORT_PROFILE_MAX);
        }

        if (port[IFLA_PORT_INSTANCE_UUID]) {
                pp->set |= ENIC_SET_INSTANCE;
                memcpy(pp->instance_uuid,
                        nla_data(port[IFLA_PORT_INSTANCE_UUID]), PORT_UUID_MAX);
        }

        if (port[IFLA_PORT_HOST_UUID]) {
                pp->set |= ENIC_SET_HOST;
                memcpy(pp->host_uuid,
                        nla_data(port[IFLA_PORT_HOST_UUID]), PORT_UUID_MAX);
        }

        if (vf == PORT_SELF_VF) {
                /* Special case handling: mac came from IFLA_VF_MAC */
                if (!is_zero_ether_addr(prev_pp.vf_mac))
                        memcpy(pp->mac_addr, prev_pp.vf_mac, ETH_ALEN);

                if (is_zero_ether_addr(netdev->dev_addr))
                        eth_hw_addr_random(netdev);
        } else {
                /* SR-IOV VF: get mac from adapter */
                ENIC_DEVCMD_PROXY_BY_INDEX(vf, err, enic,
                        vnic_dev_get_mac_addr, pp->mac_addr);
                if (err) {
                        netdev_err(netdev, "Error getting mac for vf %d\n", vf);
                        memcpy(pp, &prev_pp, sizeof(*pp));
                        return enic_dev_status_to_errno(err);
                }
        }

        err = enic_process_set_pp_request(enic, vf, &prev_pp, &restore_pp);
        if (err) {
                if (restore_pp) {
                        /* Things are still the way they were: Implicit
                         * DISASSOCIATE failed
                         */
                        memcpy(pp, &prev_pp, sizeof(*pp));
                } else {
                        memset(pp, 0, sizeof(*pp));
                        if (vf == PORT_SELF_VF)
                                eth_zero_addr(netdev->dev_addr);
                }
        } else {
                /* Set flag to indicate that the port assoc/disassoc
                 * request has been sent out to fw
                 */
                pp->set |= ENIC_PORT_REQUEST_APPLIED;

                /* If DISASSOCIATE, clean up all assigned/saved macaddresses */
                if (pp->request == PORT_REQUEST_DISASSOCIATE) {
                        eth_zero_addr(pp->mac_addr);
                        if (vf == PORT_SELF_VF)
                                eth_zero_addr(netdev->dev_addr);
                }
        }

        if (vf == PORT_SELF_VF)
                eth_zero_addr(pp->vf_mac);

        return err;
}

static int enic_get_vf_port(struct net_device *netdev, int vf,
        struct sk_buff *skb)
{
        struct enic *enic = netdev_priv(netdev);
        u16 response = PORT_PROFILE_RESPONSE_SUCCESS;
        struct enic_port_profile *pp;
        int err;

        ENIC_PP_BY_INDEX(enic, vf, pp, &err);
        if (err)
                return err;

        if (!(pp->set & ENIC_PORT_REQUEST_APPLIED))
                return -ENODATA;

        err = enic_process_get_pp_request(enic, vf, pp->request, &response);
        if (err)
                return err;

        if (nla_put_u16(skb, IFLA_PORT_REQUEST, pp->request) ||
            nla_put_u16(skb, IFLA_PORT_RESPONSE, response) ||
            ((pp->set & ENIC_SET_NAME) &&
             nla_put(skb, IFLA_PORT_PROFILE, PORT_PROFILE_MAX, pp->name)) ||
            ((pp->set & ENIC_SET_INSTANCE) &&
             nla_put(skb, IFLA_PORT_INSTANCE_UUID, PORT_UUID_MAX,
                     pp->instance_uuid)) ||
            ((pp->set & ENIC_SET_HOST) &&
             nla_put(skb, IFLA_PORT_HOST_UUID, PORT_UUID_MAX, pp->host_uuid)))
                goto nla_put_failure;
        return 0;

nla_put_failure:
        return -EMSGSIZE;
}

static void enic_free_rq_buf(struct vnic_rq *rq, struct vnic_rq_buf *buf)
{
        struct enic *enic = vnic_dev_priv(rq->vdev);

        if (!buf->os_buf)
                return;

        dma_unmap_single(&enic->pdev->dev, buf->dma_addr, buf->len,
                         DMA_FROM_DEVICE);
        dev_kfree_skb_any(buf->os_buf);
        buf->os_buf = NULL;
}

static int enic_rq_alloc_buf(struct vnic_rq *rq)
{
        struct enic *enic = vnic_dev_priv(rq->vdev);
        struct net_device *netdev = enic->netdev;
        struct sk_buff *skb;
        unsigned int len = netdev->mtu + VLAN_ETH_HLEN;
        unsigned int os_buf_index = 0;
        dma_addr_t dma_addr;
        struct vnic_rq_buf *buf = rq->to_use;

        if (buf->os_buf) {
                enic_queue_rq_desc(rq, buf->os_buf, os_buf_index, buf->dma_addr,
                                   buf->len);

                return 0;
        }
        skb = netdev_alloc_skb_ip_align(netdev, len);
        if (!skb)
                return -ENOMEM;

        dma_addr = dma_map_single(&enic->pdev->dev, skb->data, len,
                                  DMA_FROM_DEVICE);
        if (unlikely(enic_dma_map_check(enic, dma_addr))) {
                dev_kfree_skb(skb);
                return -ENOMEM;
        }

        enic_queue_rq_desc(rq, skb, os_buf_index,
                dma_addr, len);

        return 0;
}

static void enic_intr_update_pkt_size(struct vnic_rx_bytes_counter *pkt_size,
                                      u32 pkt_len)
{
        if (ENIC_LARGE_PKT_THRESHOLD <= pkt_len)
                pkt_size->large_pkt_bytes_cnt += pkt_len;
        else
                pkt_size->small_pkt_bytes_cnt += pkt_len;
}

static bool enic_rxcopybreak(struct net_device *netdev, struct sk_buff **skb,
                             struct vnic_rq_buf *buf, u16 len)
{
        struct enic *enic = netdev_priv(netdev);
        struct sk_buff *new_skb;

        if (len > enic->rx_copybreak)
                return false;
        new_skb = netdev_alloc_skb_ip_align(netdev, len);
        if (!new_skb)
                return false;
        dma_sync_single_for_cpu(&enic->pdev->dev, buf->dma_addr, len,
                                DMA_FROM_DEVICE);
        memcpy(new_skb->data, (*skb)->data, len);
        *skb = new_skb;

        return true;
}

static void enic_rq_indicate_buf(struct vnic_rq *rq,
        struct cq_desc *cq_desc, struct vnic_rq_buf *buf,
        int skipped, void *opaque)
{
        struct enic *enic = vnic_dev_priv(rq->vdev);
        struct net_device *netdev = enic->netdev;
        struct sk_buff *skb;
        struct vnic_cq *cq = &enic->cq[enic_cq_rq(enic, rq->index)];

        u8 type, color, eop, sop, ingress_port, vlan_stripped;
        u8 fcoe, fcoe_sof, fcoe_fc_crc_ok, fcoe_enc_error, fcoe_eof;
        u8 tcp_udp_csum_ok, udp, tcp, ipv4_csum_ok;
        u8 ipv6, ipv4, ipv4_fragment, fcs_ok, rss_type, csum_not_calc;
        u8 packet_error;
        u16 q_number, completed_index, bytes_written, vlan_tci, checksum;
        u32 rss_hash;
        bool outer_csum_ok = true, encap = false;

        if (skipped)
                return;

        skb = buf->os_buf;

        cq_enet_rq_desc_dec((struct cq_enet_rq_desc *)cq_desc,
                &type, &color, &q_number, &completed_index,
                &ingress_port, &fcoe, &eop, &sop, &rss_type,
                &csum_not_calc, &rss_hash, &bytes_written,
                &packet_error, &vlan_stripped, &vlan_tci, &checksum,
                &fcoe_sof, &fcoe_fc_crc_ok, &fcoe_enc_error,
                &fcoe_eof, &tcp_udp_csum_ok, &udp, &tcp,
                &ipv4_csum_ok, &ipv6, &ipv4, &ipv4_fragment,
                &fcs_ok);

        if (packet_error) {

                if (!fcs_ok) {
                        if (bytes_written > 0)
                                enic->rq_bad_fcs++;
                        else if (bytes_written == 0)
                                enic->rq_truncated_pkts++;
                }

                dma_unmap_single(&enic->pdev->dev, buf->dma_addr, buf->len,
                                 DMA_FROM_DEVICE);
                dev_kfree_skb_any(skb);
                buf->os_buf = NULL;

                return;
        }

        if (eop && bytes_written > 0) {

                /* Good receive
                 */

                if (!enic_rxcopybreak(netdev, &skb, buf, bytes_written)) {
                        buf->os_buf = NULL;
                        dma_unmap_single(&enic->pdev->dev, buf->dma_addr,
                                         buf->len, DMA_FROM_DEVICE);
                }
                prefetch(skb->data - NET_IP_ALIGN);

                skb_put(skb, bytes_written);
                skb->protocol = eth_type_trans(skb, netdev);
                skb_record_rx_queue(skb, q_number);
                if ((netdev->features & NETIF_F_RXHASH) && rss_hash &&
                    (type == 3)) {
                        switch (rss_type) {
                        case CQ_ENET_RQ_DESC_RSS_TYPE_TCP_IPv4:
                        case CQ_ENET_RQ_DESC_RSS_TYPE_TCP_IPv6:
                        case CQ_ENET_RQ_DESC_RSS_TYPE_TCP_IPv6_EX:
                                skb_set_hash(skb, rss_hash, PKT_HASH_TYPE_L4);
                                break;
                        case CQ_ENET_RQ_DESC_RSS_TYPE_IPv4:
                        case CQ_ENET_RQ_DESC_RSS_TYPE_IPv6:
                        case CQ_ENET_RQ_DESC_RSS_TYPE_IPv6_EX:
                                skb_set_hash(skb, rss_hash, PKT_HASH_TYPE_L3);
                                break;
                        }
                }
                if (enic->vxlan.vxlan_udp_port_number) {
                        switch (enic->vxlan.patch_level) {
                        case 0:
                                if (fcoe) {
                                        encap = true;
                                        outer_csum_ok = fcoe_fc_crc_ok;
                                }
                                break;
                        case 2:
                                if ((type == 7) &&
                                    (rss_hash & BIT(0))) {
                                        encap = true;
                                        outer_csum_ok = (rss_hash & BIT(1)) &&
                                                        (rss_hash & BIT(2));
                                }
                                break;
                        }
                }

                /* Hardware does not provide whole packet checksum. It only
                 * provides pseudo checksum. Since hw validates the packet
                 * checksum but not provide us the checksum value. use
                 * CHECSUM_UNNECESSARY.
                 *
                 * In case of encap pkt tcp_udp_csum_ok/tcp_udp_csum_ok is
                 * inner csum_ok. outer_csum_ok is set by hw when outer udp
                 * csum is correct or is zero.
                 */
                if ((netdev->features & NETIF_F_RXCSUM) && !csum_not_calc &&
                    tcp_udp_csum_ok && outer_csum_ok &&
                    (ipv4_csum_ok || ipv6)) {
                        skb->ip_summed = CHECKSUM_UNNECESSARY;
                        skb->csum_level = encap;
                }

                if (vlan_stripped)
                        __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tci);

                skb_mark_napi_id(skb, &enic->napi[rq->index]);
                if (!(netdev->features & NETIF_F_GRO))
                        netif_receive_skb(skb);
                else
                        napi_gro_receive(&enic->napi[q_number], skb);
                if (enic->rx_coalesce_setting.use_adaptive_rx_coalesce)
                        enic_intr_update_pkt_size(&cq->pkt_size_counter,
                                                  bytes_written);
        } else {

                /* Buffer overflow
                 */

                dma_unmap_single(&enic->pdev->dev, buf->dma_addr, buf->len,
                                 DMA_FROM_DEVICE);
                dev_kfree_skb_any(skb);
                buf->os_buf = NULL;
        }
}

static int enic_rq_service(struct vnic_dev *vdev, struct cq_desc *cq_desc,
        u8 type, u16 q_number, u16 completed_index, void *opaque)
{
        struct enic *enic = vnic_dev_priv(vdev);

        vnic_rq_service(&enic->rq[q_number], cq_desc,
                completed_index, VNIC_RQ_RETURN_DESC,
                enic_rq_indicate_buf, opaque);

        return 0;
}

static void enic_set_int_moderation(struct enic *enic, struct vnic_rq *rq)
{
        unsigned int intr = enic_msix_rq_intr(enic, rq->index);
        struct vnic_cq *cq = &enic->cq[enic_cq_rq(enic, rq->index)];
        u32 timer = cq->tobe_rx_coal_timeval;

        if (cq->tobe_rx_coal_timeval != cq->cur_rx_coal_timeval) {
                vnic_intr_coalescing_timer_set(&enic->intr[intr], timer);
                cq->cur_rx_coal_timeval = cq->tobe_rx_coal_timeval;
        }
}

static void enic_calc_int_moderation(struct enic *enic, struct vnic_rq *rq)
{
        struct enic_rx_coal *rx_coal = &enic->rx_coalesce_setting;
        struct vnic_cq *cq = &enic->cq[enic_cq_rq(enic, rq->index)];
        struct vnic_rx_bytes_counter *pkt_size_counter = &cq->pkt_size_counter;
        int index;
        u32 timer;
        u32 range_start;
        u32 traffic;
        u64 delta;
        ktime_t now = ktime_get();

        delta = ktime_us_delta(now, cq->prev_ts);
        if (delta < ENIC_AIC_TS_BREAK)
                return;
        cq->prev_ts = now;

        traffic = pkt_size_counter->large_pkt_bytes_cnt +
                  pkt_size_counter->small_pkt_bytes_cnt;
        /* The table takes Mbps
         * traffic *= 8    => bits
         * traffic *= (10^6 / delta)    => bps
         * traffic /= 10^6     => Mbps
         *
         * Combining, traffic *= (8 / delta)
         */

        traffic <<= 3;
        traffic = delta > UINT_MAX ? 0 : traffic / (u32)delta;

        for (index = 0; index < ENIC_MAX_COALESCE_TIMERS; index++)
                if (traffic < mod_table[index].rx_rate)
                        break;
        range_start = (pkt_size_counter->small_pkt_bytes_cnt >
                       pkt_size_counter->large_pkt_bytes_cnt << 1) ?
                      rx_coal->small_pkt_range_start :
                      rx_coal->large_pkt_range_start;
        timer = range_start + ((rx_coal->range_end - range_start) *
                               mod_table[index].range_percent / 100);
        /* Damping */
        cq->tobe_rx_coal_timeval = (timer + cq->tobe_rx_coal_timeval) >> 1;

        pkt_size_counter->large_pkt_bytes_cnt = 0;
        pkt_size_counter->small_pkt_bytes_cnt = 0;
}

static int enic_poll(struct napi_struct *napi, int budget)
{
        struct net_device *netdev = napi->dev;
        struct enic *enic = netdev_priv(netdev);
        unsigned int cq_rq = enic_cq_rq(enic, 0);
        unsigned int cq_wq = enic_cq_wq(enic, 0);
        unsigned int intr = enic_legacy_io_intr();
        unsigned int rq_work_to_do = budget;
        unsigned int wq_work_to_do = ENIC_WQ_NAPI_BUDGET;
        unsigned int  work_done, rq_work_done = 0, wq_work_done;
        int err;

        wq_work_done = vnic_cq_service(&enic->cq[cq_wq], wq_work_to_do,
                                       enic_wq_service, NULL);

        if (budget > 0)
                rq_work_done = vnic_cq_service(&enic->cq[cq_rq],
                        rq_work_to_do, enic_rq_service, NULL);

        /* Accumulate intr event credits for this polling
         * cycle.  An intr event is the completion of a
         * a WQ or RQ packet.
         */

        work_done = rq_work_done + wq_work_done;

        if (work_done > 0)
                vnic_intr_return_credits(&enic->intr[intr],
                        work_done,
                        0 /* don't unmask intr */,
                        0 /* don't reset intr timer */);

        err = vnic_rq_fill(&enic->rq[0], enic_rq_alloc_buf);

        /* Buffer allocation failed. Stay in polling
         * mode so we can try to fill the ring again.
         */

        if (err)
                rq_work_done = rq_work_to_do;
        if (enic->rx_coalesce_setting.use_adaptive_rx_coalesce)
                /* Call the function which refreshes the intr coalescing timer
                 * value based on the traffic.
                 */
                enic_calc_int_moderation(enic, &enic->rq[0]);

        if ((rq_work_done < budget) && napi_complete_done(napi, rq_work_done)) {

                /* Some work done, but not enough to stay in polling,
                 * exit polling
                 */

                if (enic->rx_coalesce_setting.use_adaptive_rx_coalesce)
                        enic_set_int_moderation(enic, &enic->rq[0]);
                vnic_intr_unmask(&enic->intr[intr]);
        }

        return rq_work_done;
}

#ifdef CONFIG_RFS_ACCEL
static void enic_free_rx_cpu_rmap(struct enic *enic)
{
        free_irq_cpu_rmap(enic->netdev->rx_cpu_rmap);
        enic->netdev->rx_cpu_rmap = NULL;
}

static void enic_set_rx_cpu_rmap(struct enic *enic)
{
        int i, res;

        if (vnic_dev_get_intr_mode(enic->vdev) == VNIC_DEV_INTR_MODE_MSIX) {
                enic->netdev->rx_cpu_rmap = alloc_irq_cpu_rmap(enic->rq_count);
                if (unlikely(!enic->netdev->rx_cpu_rmap))
                        return;
                for (i = 0; i < enic->rq_count; i++) {
                        res = irq_cpu_rmap_add(enic->netdev->rx_cpu_rmap,
                                               enic->msix_entry[i].vector);
                        if (unlikely(res)) {
                                enic_free_rx_cpu_rmap(enic);
                                return;
                        }
                }
        }
}

#else

static void enic_free_rx_cpu_rmap(struct enic *enic)
{
}

static void enic_set_rx_cpu_rmap(struct enic *enic)
{
}

#endif /* CONFIG_RFS_ACCEL */

static int enic_poll_msix_wq(struct napi_struct *napi, int budget)
{
        struct net_device *netdev = napi->dev;
        struct enic *enic = netdev_priv(netdev);
        unsigned int wq_index = (napi - &enic->napi[0]) - enic->rq_count;
        struct vnic_wq *wq = &enic->wq[wq_index];
        unsigned int cq;
        unsigned int intr;
        unsigned int wq_work_to_do = ENIC_WQ_NAPI_BUDGET;
        unsigned int wq_work_done;
        unsigned int wq_irq;

        wq_irq = wq->index;
        cq = enic_cq_wq(enic, wq_irq);
        intr = enic_msix_wq_intr(enic, wq_irq);
        wq_work_done = vnic_cq_service(&enic->cq[cq], wq_work_to_do,
                                       enic_wq_service, NULL);

        vnic_intr_return_credits(&enic->intr[intr], wq_work_done,
                                 0 /* don't unmask intr */,
                                 1 /* reset intr timer */);
        if (!wq_work_done) {
                napi_complete(napi);
                vnic_intr_unmask(&enic->intr[intr]);
                return 0;
        }

        return budget;
}

static int enic_poll_msix_rq(struct napi_struct *napi, int budget)
{
        struct net_device *netdev = napi->dev;
        struct enic *enic = netdev_priv(netdev);
        unsigned int rq = (napi - &enic->napi[0]);
        unsigned int cq = enic_cq_rq(enic, rq);
        unsigned int intr = enic_msix_rq_intr(enic, rq);
        unsigned int work_to_do = budget;
        unsigned int work_done = 0;
        int err;

        /* Service RQ
         */

        if (budget > 0)
                work_done = vnic_cq_service(&enic->cq[cq],
                        work_to_do, enic_rq_service, NULL);

        /* Return intr event credits for this polling
         * cycle.  An intr event is the completion of a
         * RQ packet.
         */

        if (work_done > 0)
                vnic_intr_return_credits(&enic->intr[intr],
                        work_done,
                        0 /* don't unmask intr */,
                        0 /* don't reset intr timer */);

        err = vnic_rq_fill(&enic->rq[rq], enic_rq_alloc_buf);

        /* Buffer allocation failed. Stay in polling mode
         * so we can try to fill the ring again.
         */

        if (err)
                work_done = work_to_do;
        if (enic->rx_coalesce_setting.use_adaptive_rx_coalesce)
                /* Call the function which refreshes the intr coalescing timer
                 * value based on the traffic.
                 */
                enic_calc_int_moderation(enic, &enic->rq[rq]);

        if ((work_done < budget) && napi_complete_done(napi, work_done)) {

                /* Some work done, but not enough to stay in polling,
                 * exit polling
                 */

                if (enic->rx_coalesce_setting.use_adaptive_rx_coalesce)
                        enic_set_int_moderation(enic, &enic->rq[rq]);
                vnic_intr_unmask(&enic->intr[intr]);
        }

        return work_done;
}

static void enic_notify_timer(struct timer_list *t)
{
        struct enic *enic = from_timer(enic, t, notify_timer);

        enic_notify_check(enic);

        mod_timer(&enic->notify_timer,
                round_jiffies(jiffies + ENIC_NOTIFY_TIMER_PERIOD));
}

static void enic_free_intr(struct enic *enic)
{
        struct net_device *netdev = enic->netdev;
        unsigned int i;

        enic_free_rx_cpu_rmap(enic);
        switch (vnic_dev_get_intr_mode(enic->vdev)) {
        case VNIC_DEV_INTR_MODE_INTX:
                free_irq(enic->pdev->irq, netdev);
                break;
        case VNIC_DEV_INTR_MODE_MSI:
                free_irq(enic->pdev->irq, enic);
                break;
        case VNIC_DEV_INTR_MODE_MSIX:
                for (i = 0; i < ARRAY_SIZE(enic->msix); i++)
                        if (enic->msix[i].requested)
                                free_irq(enic->msix_entry[i].vector,
                                        enic->msix[i].devid);
                break;
        default:
                break;
        }
}

static int enic_request_intr(struct enic *enic)
{
        struct net_device *netdev = enic->netdev;
        unsigned int i, intr;
        int err = 0;

        enic_set_rx_cpu_rmap(enic);
        switch (vnic_dev_get_intr_mode(enic->vdev)) {

        case VNIC_DEV_INTR_MODE_INTX:

                err = request_irq(enic->pdev->irq, enic_isr_legacy,
                        IRQF_SHARED, netdev->name, netdev);
                break;

        case VNIC_DEV_INTR_MODE_MSI:

                err = request_irq(enic->pdev->irq, enic_isr_msi,
                        0, netdev->name, enic);
                break;

        case VNIC_DEV_INTR_MODE_MSIX:

                for (i = 0; i < enic->rq_count; i++) {
                        intr = enic_msix_rq_intr(enic, i);
                        snprintf(enic->msix[intr].devname,
                                sizeof(enic->msix[intr].devname),
                                "%s-rx-%u", netdev->name, i);
                        enic->msix[intr].isr = enic_isr_msix;
                        enic->msix[intr].devid = &enic->napi[i];
                }

                for (i = 0; i < enic->wq_count; i++) {
                        int wq = enic_cq_wq(enic, i);

                        intr = enic_msix_wq_intr(enic, i);
                        snprintf(enic->msix[intr].devname,
                                sizeof(enic->msix[intr].devname),
                                "%s-tx-%u", netdev->name, i);
                        enic->msix[intr].isr = enic_isr_msix;
                        enic->msix[intr].devid = &enic->napi[wq];
                }

                intr = enic_msix_err_intr(enic);
                snprintf(enic->msix[intr].devname,
                        sizeof(enic->msix[intr].devname),
                        "%s-err", netdev->name);
                enic->msix[intr].isr = enic_isr_msix_err;
                enic->msix[intr].devid = enic;

                intr = enic_msix_notify_intr(enic);
                snprintf(enic->msix[intr].devname,
                        sizeof(enic->msix[intr].devname),
                        "%s-notify", netdev->name);
                enic->msix[intr].isr = enic_isr_msix_notify;
                enic->msix[intr].devid = enic;

                for (i = 0; i < ARRAY_SIZE(enic->msix); i++)
                        enic->msix[i].requested = 0;

                for (i = 0; i < enic->intr_count; i++) {
                        err = request_irq(enic->msix_entry[i].vector,
                                enic->msix[i].isr, 0,
                                enic->msix[i].devname,
                                enic->msix[i].devid);
                        if (err) {
                                enic_free_intr(enic);
                                break;
                        }
                        enic->msix[i].requested = 1;
                }

                break;

        default:
                break;
        }

        return err;
}

static void enic_synchronize_irqs(struct enic *enic)
{
        unsigned int i;

        switch (vnic_dev_get_intr_mode(enic->vdev)) {
        case VNIC_DEV_INTR_MODE_INTX:
        case VNIC_DEV_INTR_MODE_MSI:
                synchronize_irq(enic->pdev->irq);
                break;
        case VNIC_DEV_INTR_MODE_MSIX:
                for (i = 0; i < enic->intr_count; i++)
                        synchronize_irq(enic->msix_entry[i].vector);
                break;
        default:
                break;
        }
}

static void enic_set_rx_coal_setting(struct enic *enic)
{
        unsigned int speed;
        int index = -1;
        struct enic_rx_coal *rx_coal = &enic->rx_coalesce_setting;

        /* 1. Read the link speed from fw
         * 2. Pick the default range for the speed
         * 3. Update it in enic->rx_coalesce_setting
         */
        speed = vnic_dev_port_speed(enic->vdev);
        if (ENIC_LINK_SPEED_10G < speed)
                index = ENIC_LINK_40G_INDEX;
        else if (ENIC_LINK_SPEED_4G < speed)
                index = ENIC_LINK_10G_INDEX;
        else
                index = ENIC_LINK_4G_INDEX;

        rx_coal->small_pkt_range_start = mod_range[index].small_pkt_range_start;
        rx_coal->large_pkt_range_start = mod_range[index].large_pkt_range_start;
        rx_coal->range_end = ENIC_RX_COALESCE_RANGE_END;

        /* Start with the value provided by UCSM */
        for (index = 0; index < enic->rq_count; index++)
                enic->cq[index].cur_rx_coal_timeval =
                                enic->config.intr_timer_usec;

        rx_coal->use_adaptive_rx_coalesce = 1;
}

static int enic_dev_notify_set(struct enic *enic)
{
        int err;

        spin_lock_bh(&enic->devcmd_lock);
        switch (vnic_dev_get_intr_mode(enic->vdev)) {
        case VNIC_DEV_INTR_MODE_INTX:
                err = vnic_dev_notify_set(enic->vdev,
                        enic_legacy_notify_intr());
                break;
        case VNIC_DEV_INTR_MODE_MSIX:
                err = vnic_dev_notify_set(enic->vdev,
                        enic_msix_notify_intr(enic));
                break;
        default:
                err = vnic_dev_notify_set(enic->vdev, -1 /* no intr */);
                break;
        }
        spin_unlock_bh(&enic->devcmd_lock);

        return err;
}

static void enic_notify_timer_start(struct enic *enic)
{
        switch (vnic_dev_get_intr_mode(enic->vdev)) {
        case VNIC_DEV_INTR_MODE_MSI:
                mod_timer(&enic->notify_timer, jiffies);
                break;
        default:
                /* Using intr for notification for INTx/MSI-X */
                break;
        }
}

/* rtnl lock is held, process context */
static int enic_open(struct net_device *netdev)
{
        struct enic *enic = netdev_priv(netdev);
        unsigned int i;
        int err, ret;

        err = enic_request_intr(enic);
        if (err) {
                netdev_err(netdev, "Unable to request irq.\n");
                return err;
        }
        enic_init_affinity_hint(enic);
        enic_set_affinity_hint(enic);

        err = enic_dev_notify_set(enic);
        if (err) {
                netdev_err(netdev,
                        "Failed to alloc notify buffer, aborting.\n");
                goto err_out_free_intr;
        }

        for (i = 0; i < enic->rq_count; i++) {
                /* enable rq before updating rq desc */
                vnic_rq_enable(&enic->rq[i]);
                vnic_rq_fill(&enic->rq[i], enic_rq_alloc_buf);
                /* Need at least one buffer on ring to get going */
                if (vnic_rq_desc_used(&enic->rq[i]) == 0) {
                        netdev_err(netdev, "Unable to alloc receive buffers\n");
                        err = -ENOMEM;
                        goto err_out_free_rq;
                }
        }

        for (i = 0; i < enic->wq_count; i++)
                vnic_wq_enable(&enic->wq[i]);

        if (!enic_is_dynamic(enic) && !enic_is_sriov_vf(enic))
                enic_dev_add_station_addr(enic);

        enic_set_rx_mode(netdev);

        netif_tx_wake_all_queues(netdev);

        for (i = 0; i < enic->rq_count; i++)
                napi_enable(&enic->napi[i]);

        if (vnic_dev_get_intr_mode(enic->vdev) == VNIC_DEV_INTR_MODE_MSIX)
                for (i = 0; i < enic->wq_count; i++)
                        napi_enable(&enic->napi[enic_cq_wq(enic, i)]);
        enic_dev_enable(enic);

        for (i = 0; i < enic->intr_count; i++)
                vnic_intr_unmask(&enic->intr[i]);

        enic_notify_timer_start(enic);
        enic_rfs_timer_start(enic);

        return 0;

err_out_free_rq:
        for (i = 0; i < enic->rq_count; i++) {
                ret = vnic_rq_disable(&enic->rq[i]);
                if (!ret)
                        vnic_rq_clean(&enic->rq[i], enic_free_rq_buf);
        }
        enic_dev_notify_unset(enic);
err_out_free_intr:
        enic_unset_affinity_hint(enic);
        enic_free_intr(enic);

        return err;
}

/* rtnl lock is held, process context */
static int enic_stop(struct net_device *netdev)
{
        struct enic *enic = netdev_priv(netdev);
        unsigned int i;
        int err;

        for (i = 0; i < enic->intr_count; i++) {
                vnic_intr_mask(&enic->intr[i]);
                (void)vnic_intr_masked(&enic->intr[i]); /* flush write */
        }

        enic_synchronize_irqs(enic);

        del_timer_sync(&enic->notify_timer);
        enic_rfs_flw_tbl_free(enic);

        enic_dev_disable(enic);

        for (i = 0; i < enic->rq_count; i++)
                napi_disable(&enic->napi[i]);

        netif_carrier_off(netdev);
        if (vnic_dev_get_intr_mode(enic->vdev) == VNIC_DEV_INTR_MODE_MSIX)
                for (i = 0; i < enic->wq_count; i++)
                        napi_disable(&enic->napi[enic_cq_wq(enic, i)]);
        netif_tx_disable(netdev);

        if (!enic_is_dynamic(enic) && !enic_is_sriov_vf(enic))
                enic_dev_del_station_addr(enic);

        for (i = 0; i < enic->wq_count; i++) {
                err = vnic_wq_disable(&enic->wq[i]);
                if (err)
                        return err;
        }
        for (i = 0; i < enic->rq_count; i++) {
                err = vnic_rq_disable(&enic->rq[i]);
                if (err)
                        return err;