root/sys/dev/virtual/amazon/ena/ena.c
/*-
 * BSD LICENSE
 *
 * Copyright (c) 2015-2017 Amazon.com, Inc. or its affiliates.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * $FreeBSD: head/sys/dev/ena/ena.c 325593 2017-11-09 13:38:17Z mw $
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/endian.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/module.h>
#include <sys/rman.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/sysctl.h>
#include <sys/taskqueue.h>
#include <sys/time.h>
#include <sys/eventhandler.h>

#include <net/bpf.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_arp.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_types.h>
#include <net/ifq_var.h>
#include <net/vlan/if_vlan_var.h>

#include <netinet/in_systm.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <netinet/ip.h>
#include <netinet/ip6.h>
#include <netinet/tcp.h>
#include <netinet/udp.h>

#include <bus/pci/pcivar.h>
#include <bus/pci/pcireg.h>

#include "ena.h"
#include "ena_sysctl.h"

/*********************************************************
 *  Function prototypes
 *********************************************************/
static int      ena_probe(device_t);
static void     ena_intr_msix_mgmnt(void *);
static int      ena_allocate_pci_resources(struct ena_adapter*);
static void     ena_free_pci_resources(struct ena_adapter *);
static int      ena_change_mtu(if_t, int);
#if 0 /* XXX swildner counters */
static inline void ena_alloc_counters(counter_u64_t *, int);
static inline void ena_free_counters(counter_u64_t *, int);
static inline void ena_reset_counters(counter_u64_t *, int);
#endif
static void     ena_init_io_rings_common(struct ena_adapter *,
    struct ena_ring *, uint16_t);
static void     ena_init_io_rings(struct ena_adapter *);
static void     ena_free_io_ring_resources(struct ena_adapter *, unsigned int);
static void     ena_free_all_io_rings_resources(struct ena_adapter *);
static int      ena_setup_tx_dma_tag(struct ena_adapter *);
static int      ena_free_tx_dma_tag(struct ena_adapter *);
static int      ena_setup_rx_dma_tag(struct ena_adapter *);
static int      ena_free_rx_dma_tag(struct ena_adapter *);
static int      ena_setup_tx_resources(struct ena_adapter *, int);
static void     ena_free_tx_resources(struct ena_adapter *, int);
static int      ena_setup_all_tx_resources(struct ena_adapter *);
static void     ena_free_all_tx_resources(struct ena_adapter *);
static inline int validate_rx_req_id(struct ena_ring *, uint16_t);
static int      ena_setup_rx_resources(struct ena_adapter *, unsigned int);
static void     ena_free_rx_resources(struct ena_adapter *, unsigned int);
static int      ena_setup_all_rx_resources(struct ena_adapter *);
static void     ena_free_all_rx_resources(struct ena_adapter *);
static inline int ena_alloc_rx_mbuf(struct ena_adapter *, struct ena_ring *,
    struct ena_rx_buffer *);
static void     ena_free_rx_mbuf(struct ena_adapter *, struct ena_ring *,
    struct ena_rx_buffer *);
static int      ena_refill_rx_bufs(struct ena_ring *, uint32_t);
static void     ena_free_rx_bufs(struct ena_adapter *, unsigned int);
static void     ena_refill_all_rx_bufs(struct ena_adapter *);
static void     ena_free_all_rx_bufs(struct ena_adapter *);
static void     ena_free_tx_bufs(struct ena_adapter *, unsigned int);
static void     ena_free_all_tx_bufs(struct ena_adapter *);
static void     ena_destroy_all_tx_queues(struct ena_adapter *);
static void     ena_destroy_all_rx_queues(struct ena_adapter *);
static void     ena_destroy_all_io_queues(struct ena_adapter *);
static int      ena_create_io_queues(struct ena_adapter *);
static int      ena_tx_cleanup(struct ena_ring *);
static void     ena_deferred_rx_cleanup(void *, int);
static int      ena_rx_cleanup(struct ena_ring *);
static inline int validate_tx_req_id(struct ena_ring *, uint16_t);
static void     ena_rx_hash_mbuf(struct ena_ring *, struct ena_com_rx_ctx *,
    struct mbuf *);
static struct mbuf* ena_rx_mbuf(struct ena_ring *, struct ena_com_rx_buf_info *,
    struct ena_com_rx_ctx *, uint16_t *);
static inline void ena_rx_checksum(struct ena_ring *, struct ena_com_rx_ctx *,
    struct mbuf *);
static void     ena_handle_msix(void *);
static int      ena_enable_msix(struct ena_adapter *);
static void     ena_setup_mgmnt_intr(struct ena_adapter *);
static void     ena_setup_io_intr(struct ena_adapter *);
static int      ena_request_mgmnt_irq(struct ena_adapter *);
static int      ena_request_io_irq(struct ena_adapter *);
static void     ena_free_mgmnt_irq(struct ena_adapter *);
static void     ena_free_io_irq(struct ena_adapter *);
static void     ena_free_irqs(struct ena_adapter*);
static void     ena_disable_msix(struct ena_adapter *);
static void     ena_unmask_all_io_irqs(struct ena_adapter *);
static int      ena_rss_configure(struct ena_adapter *);
static int      ena_up_complete(struct ena_adapter *);
static int      ena_up(struct ena_adapter *);
static void     ena_down(struct ena_adapter *);
#if 0 /* XXX swildner counters */
static uint64_t ena_get_counter(if_t, ift_counter);
#endif
static int      ena_media_change(if_t);
static void     ena_media_status(if_t, struct ifmediareq *);
static void     ena_init(void *);
static int      ena_ioctl(if_t, u_long, caddr_t, struct ucred *);
static int      ena_get_dev_offloads(struct ena_com_dev_get_features_ctx *);
static void     ena_update_host_info(struct ena_admin_host_info *, if_t);
static void     ena_update_hwassist(struct ena_adapter *);
static int      ena_setup_ifnet(device_t, struct ena_adapter *,
    struct ena_com_dev_get_features_ctx *);
static void     ena_tx_csum(struct ena_com_tx_ctx *, struct mbuf *);
static int      ena_check_and_collapse_mbuf(struct ena_ring *tx_ring,
    struct mbuf **mbuf);
static int      ena_xmit_mbuf(struct ena_ring *, struct mbuf **);
static void     ena_start_xmit(struct ifnet *, struct ifaltq_subque *);
static int      ena_calc_io_queue_num(struct ena_adapter *,
    struct ena_com_dev_get_features_ctx *);
static int      ena_calc_queue_size(struct ena_adapter *, uint16_t *,
    uint16_t *, struct ena_com_dev_get_features_ctx *);
static int      ena_rss_init_default(struct ena_adapter *);
static void     ena_rss_init_default_deferred(void *);
static void     ena_config_host_info(struct ena_com_dev *);
static int      ena_attach(device_t);
static int      ena_detach(device_t);
static int      ena_device_init(struct ena_adapter *, device_t,
    struct ena_com_dev_get_features_ctx *, int *);
static int      ena_enable_msix_and_set_admin_interrupts(struct ena_adapter *,
    int);
static void ena_update_on_link_change(void *, struct ena_admin_aenq_entry *);
static void     unimplemented_aenq_handler(void *,
    struct ena_admin_aenq_entry *);
static void     ena_timer_service(void *);

static char ena_version[] = DEVICE_NAME DRV_MODULE_NAME " v" DRV_MODULE_VERSION;

static SYSCTL_NODE(_hw, OID_AUTO, ena, CTLFLAG_RD, 0, "ENA driver parameters");

/*
 * Logging level for changing verbosity of the output
 */
int ena_log_level = ENA_ALERT | ENA_WARNING;
TUNABLE_INT("hw.ena.ena_log_level", &ena_log_level);
SYSCTL_INT(_hw_ena, OID_AUTO, log_level, CTLFLAG_RW,
    &ena_log_level, 0, "Logging level indicating verbosity of the logs");

static ena_vendor_info_t ena_vendor_info_array[] = {
    { PCI_VENDOR_ID_AMAZON, PCI_DEV_ID_ENA_PF, 0},
    { PCI_VENDOR_ID_AMAZON, PCI_DEV_ID_ENA_LLQ_PF, 0},
    { PCI_VENDOR_ID_AMAZON, PCI_DEV_ID_ENA_VF, 0},
    { PCI_VENDOR_ID_AMAZON, PCI_DEV_ID_ENA_LLQ_VF, 0},
    /* Last entry */
    { 0, 0, 0 }
};

/*
 * Contains pointers to event handlers, e.g. link state chage.
 */
static struct ena_aenq_handlers aenq_handlers;

void
ena_dmamap_callback(void *arg, bus_dma_segment_t *segs, int nseg, int error)
{
        if (error != 0)
                return;
        *(bus_addr_t *) arg = segs[0].ds_addr;
}

int
ena_dma_alloc(device_t dmadev, bus_size_t size,
    ena_mem_handle_t *dma , int mapflags)
{
        struct ena_adapter* adapter = device_get_softc(dmadev);
        uint32_t maxsize;
        uint64_t dma_space_addr;
        int error;

        maxsize = ((size - 1) / PAGE_SIZE + 1) * PAGE_SIZE;

        dma_space_addr = ENA_DMA_BIT_MASK(adapter->dma_width);
        if (unlikely(dma_space_addr == 0))
                dma_space_addr = BUS_SPACE_MAXADDR;

        error = bus_dma_tag_create(bus_get_dma_tag(dmadev), /* parent */
            8, 0,             /* alignment, bounds              */
            dma_space_addr,   /* lowaddr of exclusion window    */
            BUS_SPACE_MAXADDR,/* highaddr of exclusion window   */
            maxsize,          /* maxsize                        */
            1,                /* nsegments                      */
            maxsize,          /* maxsegsize                     */
            BUS_DMA_ALLOCNOW, /* flags                          */
            &dma->tag);
        if (unlikely(error != 0)) {
                ena_trace(ENA_ALERT, "bus_dma_tag_create failed: %d\n", error);
                goto fail_tag;
        }

        error = bus_dmamem_alloc(dma->tag, (void**) &dma->vaddr,
            BUS_DMA_COHERENT | BUS_DMA_ZERO, &dma->map);
        if (unlikely(error != 0)) {
                ena_trace(ENA_ALERT, "bus_dmamem_alloc(%ju) failed: %d\n",
                    (uintmax_t)size, error);
                goto fail_map_create;
        }

        dma->paddr = 0;
        error = bus_dmamap_load(dma->tag, dma->map, dma->vaddr,
            size, ena_dmamap_callback, &dma->paddr, mapflags);
        if (unlikely((error != 0) || (dma->paddr == 0))) {
                ena_trace(ENA_ALERT, ": bus_dmamap_load failed: %d\n", error);
                goto fail_map_load;
        }

        return (0);

fail_map_load:
        bus_dmamem_free(dma->tag, dma->vaddr, dma->map);
fail_map_create:
        bus_dma_tag_destroy(dma->tag);
fail_tag:
        dma->tag = NULL;

        return (error);
}

static int
ena_allocate_pci_resources(struct ena_adapter* adapter)
{
        device_t pdev = adapter->pdev;
        int rid;

        rid = PCIR_BAR(ENA_REG_BAR);
        adapter->memory = NULL;
        adapter->registers = bus_alloc_resource_any(pdev, SYS_RES_MEMORY,
            &rid, RF_ACTIVE);
        if (unlikely(adapter->registers == NULL)) {
                device_printf(pdev, "Unable to allocate bus resource: "
                    "registers\n");
                return (ENXIO);
        }

        return (0);
}

static void
ena_free_pci_resources(struct ena_adapter *adapter)
{
        device_t pdev = adapter->pdev;

        if (adapter->memory != NULL) {
                bus_release_resource(pdev, SYS_RES_MEMORY,
                    PCIR_BAR(ENA_MEM_BAR), adapter->memory);
        }

        if (adapter->registers != NULL) {
                bus_release_resource(pdev, SYS_RES_MEMORY,
                    PCIR_BAR(ENA_REG_BAR), adapter->registers);
        }
}

static int
ena_probe(device_t dev)
{
        ena_vendor_info_t *ent;
        char            adapter_name[60];
        uint16_t        pci_vendor_id = 0;
        uint16_t        pci_device_id = 0;

        pci_vendor_id = pci_get_vendor(dev);
        pci_device_id = pci_get_device(dev);

        ent = ena_vendor_info_array;
        while (ent->vendor_id != 0) {
                if ((pci_vendor_id == ent->vendor_id) &&
                    (pci_device_id == ent->device_id)) {
                        ena_trace(ENA_DBG, "vendor=%x device=%x ",
                            pci_vendor_id, pci_device_id);

                        ksprintf(adapter_name, DEVICE_DESC);
                        device_set_desc_copy(dev, adapter_name);
                        return (BUS_PROBE_DEFAULT);
                }

                ent++;

        }

        return (ENXIO);
}

static int
ena_change_mtu(if_t ifp, int new_mtu)
{
        struct ena_adapter *adapter = ifp->if_softc;
        int rc;

        if ((new_mtu > adapter->max_mtu) || (new_mtu < ENA_MIN_MTU)) {
                device_printf(adapter->pdev, "Invalid MTU setting. "
                    "new_mtu: %d max mtu: %d min mtu: %d\n",
                    new_mtu, adapter->max_mtu, ENA_MIN_MTU);
                return (EINVAL);
        }

        rc = ena_com_set_dev_mtu(adapter->ena_dev, new_mtu);
        if (likely(rc == 0)) {
                ena_trace(ENA_DBG, "set MTU to %d\n", new_mtu);
                ifp->if_mtu = new_mtu;
        } else {
                device_printf(adapter->pdev, "Failed to set MTU to %d\n",
                    new_mtu);
        }

        return (rc);
}

#if 0 /* XXX swildner counters */
static inline void
ena_alloc_counters(counter_u64_t *begin, int size)
{
        counter_u64_t *end = (counter_u64_t *)((char *)begin + size);

        for (; begin < end; ++begin)
                *begin = counter_u64_alloc(M_WAITOK);
}

static inline void
ena_free_counters(counter_u64_t *begin, int size)
{
        counter_u64_t *end = (counter_u64_t *)((char *)begin + size);

        for (; begin < end; ++begin)
                counter_u64_free(*begin);
}

static inline void
ena_reset_counters(counter_u64_t *begin, int size)
{
        counter_u64_t *end = (counter_u64_t *)((char *)begin + size);

        for (; begin < end; ++begin)
                counter_u64_zero(*begin);
}
#endif

static void
ena_init_io_rings_common(struct ena_adapter *adapter, struct ena_ring *ring,
    uint16_t qid)
{

        ring->qid = qid;
        ring->adapter = adapter;
        ring->ena_dev = adapter->ena_dev;
}

static void
ena_init_io_rings(struct ena_adapter *adapter)
{
        struct ena_com_dev *ena_dev;
        struct ena_ring *txr, *rxr;
        struct ena_que *que;
        int i;

        ena_dev = adapter->ena_dev;

        for (i = 0; i < adapter->num_queues; i++) {
                txr = &adapter->tx_ring[i];
                rxr = &adapter->rx_ring[i];

                /* TX/RX common ring state */
                ena_init_io_rings_common(adapter, txr, i);
                ena_init_io_rings_common(adapter, rxr, i);

                /* TX specific ring state */
                txr->ring_size = adapter->tx_ring_size;
                txr->tx_max_header_size = ena_dev->tx_max_header_size;
                txr->tx_mem_queue_type = ena_dev->tx_mem_queue_type;
                txr->smoothed_interval =
                    ena_com_get_nonadaptive_moderation_interval_tx(ena_dev);

#if 0 /* XXX swildner counters */
                /* Alloc TX statistics. */
                ena_alloc_counters((counter_u64_t *)&txr->tx_stats,
                    sizeof(txr->tx_stats));
#endif

                /* RX specific ring state */
                rxr->ring_size = adapter->rx_ring_size;
                rxr->smoothed_interval =
                    ena_com_get_nonadaptive_moderation_interval_rx(ena_dev);

#if 0 /* XXX swildner counters */
                /* Alloc RX statistics. */
                ena_alloc_counters((counter_u64_t *)&rxr->rx_stats,
                    sizeof(rxr->rx_stats));
#endif

                /* Initialize locks */
                ksnprintf(txr->lock_name, nitems(txr->lock_name), "%s:tx(%d)",
                    device_get_nameunit(adapter->pdev), i);
                ksnprintf(rxr->lock_name, nitems(rxr->lock_name), "%s:rx(%d)",
                    device_get_nameunit(adapter->pdev), i);

                lockinit(&txr->ring_lock, txr->lock_name, 0, LK_CANRECURSE);
                lockinit(&rxr->ring_lock, rxr->lock_name, 0, LK_CANRECURSE);

                que = &adapter->que[i];
                que->adapter = adapter;
                que->id = i;
                que->tx_ring = txr;
                que->rx_ring = rxr;

                txr->que = que;
                rxr->que = que;

                rxr->empty_rx_queue = 0;
        }
}

static void
ena_free_io_ring_resources(struct ena_adapter *adapter, unsigned int qid)
{
        struct ena_ring *txr = &adapter->tx_ring[qid];
        struct ena_ring *rxr = &adapter->rx_ring[qid];

#if 0 /* XXX swildner counters */
        ena_free_counters((counter_u64_t *)&txr->tx_stats,
            sizeof(txr->tx_stats));
        ena_free_counters((counter_u64_t *)&rxr->rx_stats,
            sizeof(rxr->rx_stats));
#endif

        lockuninit(&txr->ring_lock);
        lockuninit(&rxr->ring_lock);
}

static void
ena_free_all_io_rings_resources(struct ena_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_queues; i++)
                ena_free_io_ring_resources(adapter, i);

}

static int
ena_setup_tx_dma_tag(struct ena_adapter *adapter)
{
        int ret;

        /* Create DMA tag for Tx buffers */
        ret = bus_dma_tag_create(bus_get_dma_tag(adapter->pdev),
            1, 0,                                 /* alignment, bounds       */
            ENA_DMA_BIT_MASK(adapter->dma_width), /* lowaddr of excl window  */
            BUS_SPACE_MAXADDR,                    /* highaddr of excl window */
            ENA_TSO_MAXSIZE,                      /* maxsize                 */
            ENA_BUS_DMA_SEGS,                     /* nsegments               */
            ENA_TSO_MAXSIZE,                      /* maxsegsize              */
            0,                                    /* flags                   */
            &adapter->tx_buf_tag);

        return (ret);
}

static int
ena_free_tx_dma_tag(struct ena_adapter *adapter)
{
        int ret;

        ret = bus_dma_tag_destroy(adapter->tx_buf_tag);

        if (likely(ret == 0))
                adapter->tx_buf_tag = NULL;

        return (ret);
}

static int
ena_setup_rx_dma_tag(struct ena_adapter *adapter)
{
        int ret;

        /* Create DMA tag for Rx buffers*/
        ret = bus_dma_tag_create(bus_get_dma_tag(adapter->pdev), /* parent   */
            1, 0,                                 /* alignment, bounds       */
            ENA_DMA_BIT_MASK(adapter->dma_width), /* lowaddr of excl window  */
            BUS_SPACE_MAXADDR,                    /* highaddr of excl window */
            MJUM16BYTES,                          /* maxsize                 */
            adapter->max_rx_sgl_size,             /* nsegments               */
            MJUM16BYTES,                          /* maxsegsize              */
            0,                                    /* flags                   */
            &adapter->rx_buf_tag);

        return (ret);
}

static int
ena_free_rx_dma_tag(struct ena_adapter *adapter)
{
        int ret;

        ret = bus_dma_tag_destroy(adapter->rx_buf_tag);

        if (likely(ret == 0))
                adapter->rx_buf_tag = NULL;

        return (ret);
}

/**
 * ena_setup_tx_resources - allocate Tx resources (Descriptors)
 * @adapter: network interface device structure
 * @qid: queue index
 *
 * Returns 0 on success, otherwise on failure.
 **/
static int
ena_setup_tx_resources(struct ena_adapter *adapter, int qid)
{
        struct ena_que *que = &adapter->que[qid];
        struct ena_ring *tx_ring = que->tx_ring;
        int size, i, err;
#ifdef  RSS
        cpuset_t cpu_mask;
#endif

        size = sizeof(struct ena_tx_buffer) * tx_ring->ring_size;

        tx_ring->tx_buffer_info = kmalloc(size, M_DEVBUF, M_NOWAIT | M_ZERO);
        if (unlikely(tx_ring->tx_buffer_info == NULL))
                return (ENOMEM);

        size = sizeof(uint16_t) * tx_ring->ring_size;
        tx_ring->free_tx_ids = kmalloc(size, M_DEVBUF, M_NOWAIT | M_ZERO);
        if (unlikely(tx_ring->free_tx_ids == NULL))
                goto err_buf_info_free;

        /* Req id stack for TX OOO completions */
        for (i = 0; i < tx_ring->ring_size; i++)
                tx_ring->free_tx_ids[i] = i;

#if 0 /* XXX swildner counters */
        /* Reset TX statistics. */
        ena_reset_counters((counter_u64_t *)&tx_ring->tx_stats,
            sizeof(tx_ring->tx_stats));
#endif

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

        /* ... and create the buffer DMA maps */
        for (i = 0; i < tx_ring->ring_size; i++) {
                err = bus_dmamap_create(adapter->tx_buf_tag, 0,
                    &tx_ring->tx_buffer_info[i].map);
                if (unlikely(err != 0)) {
                        ena_trace(ENA_ALERT,
                             "Unable to create Tx DMA map for buffer %d\n", i);
                        goto err_buf_info_unmap;
                }
        }

        return (0);

err_buf_info_unmap:
        while (i--) {
                bus_dmamap_destroy(adapter->tx_buf_tag,
                    tx_ring->tx_buffer_info[i].map);
        }
        kfree(tx_ring->free_tx_ids, M_DEVBUF);
        tx_ring->free_tx_ids = NULL;
err_buf_info_free:
        kfree(tx_ring->tx_buffer_info, M_DEVBUF);
        tx_ring->tx_buffer_info = NULL;

        return (ENOMEM);
}

/**
 * ena_free_tx_resources - Free Tx Resources per Queue
 * @adapter: network interface device structure
 * @qid: queue index
 *
 * Free all transmit software resources
 **/
static void
ena_free_tx_resources(struct ena_adapter *adapter, int qid)
{
        struct ena_ring *tx_ring = &adapter->tx_ring[qid];

        ENA_RING_MTX_LOCK(tx_ring);

        /* Free buffer DMA maps, */
        for (int i = 0; i < tx_ring->ring_size; i++) {
                m_freem(tx_ring->tx_buffer_info[i].mbuf);
                tx_ring->tx_buffer_info[i].mbuf = NULL;
                bus_dmamap_unload(adapter->tx_buf_tag,
                    tx_ring->tx_buffer_info[i].map);
                bus_dmamap_destroy(adapter->tx_buf_tag,
                    tx_ring->tx_buffer_info[i].map);
        }
        ENA_RING_MTX_UNLOCK(tx_ring);

        /* And free allocated memory. */
        kfree(tx_ring->tx_buffer_info, M_DEVBUF);
        tx_ring->tx_buffer_info = NULL;

        kfree(tx_ring->free_tx_ids, M_DEVBUF);
        tx_ring->free_tx_ids = NULL;
}

/**
 * ena_setup_all_tx_resources - allocate all queues Tx resources
 * @adapter: network interface device structure
 *
 * Returns 0 on success, otherwise on failure.
 **/
static int
ena_setup_all_tx_resources(struct ena_adapter *adapter)
{
        int i, rc;

        for (i = 0; i < adapter->num_queues; i++) {
                rc = ena_setup_tx_resources(adapter, i);
                if (rc != 0) {
                        device_printf(adapter->pdev,
                            "Allocation for Tx Queue %u failed\n", i);
                        goto err_setup_tx;
                }
        }

        return (0);

err_setup_tx:
        /* Rewind the index freeing the rings as we go */
        while (i--)
                ena_free_tx_resources(adapter, i);
        return (rc);
}

/**
 * ena_free_all_tx_resources - Free Tx Resources for All Queues
 * @adapter: network interface device structure
 *
 * Free all transmit software resources
 **/
static void
ena_free_all_tx_resources(struct ena_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_queues; i++)
                ena_free_tx_resources(adapter, i);
}

static inline int
validate_rx_req_id(struct ena_ring *rx_ring, uint16_t req_id)
{
        if (likely(req_id < rx_ring->ring_size))
                return (0);

        device_printf(rx_ring->adapter->pdev, "Invalid rx req_id: %hu\n",
            req_id);
        IFNET_STAT_INC(rx_ring->adapter->ifp, ierrors, 1);
#if 0 /* XXX swildner counters */
        counter_u64_add(rx_ring->rx_stats.bad_req_id, 1);
#endif

        /* Trigger device reset */
        rx_ring->adapter->reset_reason = ENA_REGS_RESET_INV_RX_REQ_ID;
        rx_ring->adapter->trigger_reset = true;

        return (EFAULT);
}

/**
 * ena_setup_rx_resources - allocate Rx resources (Descriptors)
 * @adapter: network interface device structure
 * @qid: queue index
 *
 * Returns 0 on success, otherwise on failure.
 **/
static int
ena_setup_rx_resources(struct ena_adapter *adapter, unsigned int qid)
{
        struct ena_que *que = &adapter->que[qid];
        struct ena_ring *rx_ring = que->rx_ring;
        int size, err, i;
#ifdef  RSS
        cpuset_t cpu_mask;
#endif

        size = sizeof(struct ena_rx_buffer) * rx_ring->ring_size;

        /*
         * Alloc extra element so in rx path
         * we can always prefetch rx_info + 1
         */
        size += sizeof(struct ena_rx_buffer);

        rx_ring->rx_buffer_info = kmalloc(size, M_DEVBUF, M_WAITOK | M_ZERO);

        size = sizeof(uint16_t) * rx_ring->ring_size;
        rx_ring->free_rx_ids = kmalloc(size, M_DEVBUF, M_WAITOK);

        for (i = 0; i < rx_ring->ring_size; i++)
                rx_ring->free_rx_ids[i] = i;

#if 0 /* XXX swildner counters */
        /* Reset RX statistics. */
        ena_reset_counters((counter_u64_t *)&rx_ring->rx_stats,
            sizeof(rx_ring->rx_stats));
#endif

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

        /* ... and create the buffer DMA maps */
        for (i = 0; i < rx_ring->ring_size; i++) {
                err = bus_dmamap_create(adapter->rx_buf_tag, 0,
                    &(rx_ring->rx_buffer_info[i].map));
                if (err != 0) {
                        ena_trace(ENA_ALERT,
                            "Unable to create Rx DMA map for buffer %d\n", i);
                        goto err_buf_info_unmap;
                }
        }

#if 0 /* XXX LRO */
        /* Create LRO for the ring */
        if ((adapter->ifp->if_capenable & IFCAP_LRO) != 0) {
                int err = tcp_lro_init(&rx_ring->lro);
                if (err != 0) {
                        device_printf(adapter->pdev,
                            "LRO[%d] Initialization failed!\n", qid);
                } else {
                        ena_trace(ENA_INFO,
                            "RX Soft LRO[%d] Initialized\n", qid);
                        rx_ring->lro.ifp = adapter->ifp;
                }
        }
#endif

        /* Allocate taskqueues */
        TASK_INIT(&rx_ring->cmpl_task, 0, ena_deferred_rx_cleanup, rx_ring);
        rx_ring->cmpl_tq = taskqueue_create("ena RX completion", M_WAITOK,
            taskqueue_thread_enqueue, &rx_ring->cmpl_tq);

        /* RSS set cpu for thread */
#ifdef RSS
        CPU_SETOF(que->cpu, &cpu_mask);
        taskqueue_start_threads_cpuset(&rx_ring->cmpl_tq, 1, PI_NET, &cpu_mask,
            "%s rx_ring cmpl (bucket %d)",
            device_get_nameunit(adapter->pdev), que->cpu);
#else
        taskqueue_start_threads(&rx_ring->cmpl_tq, 1, TDPRI_KERN_DAEMON, -1,
            "%s rx_ring cmpl", device_get_nameunit(adapter->pdev));
#endif

        return (0);

err_buf_info_unmap:
        while (i--) {
                bus_dmamap_destroy(adapter->rx_buf_tag,
                    rx_ring->rx_buffer_info[i].map);
        }

        kfree(rx_ring->free_rx_ids, M_DEVBUF);
        rx_ring->free_rx_ids = NULL;
        kfree(rx_ring->rx_buffer_info, M_DEVBUF);
        rx_ring->rx_buffer_info = NULL;
        return (ENOMEM);
}

/**
 * ena_free_rx_resources - Free Rx Resources
 * @adapter: network interface device structure
 * @qid: queue index
 *
 * Free all receive software resources
 **/
static void
ena_free_rx_resources(struct ena_adapter *adapter, unsigned int qid)
{
        struct ena_ring *rx_ring = &adapter->rx_ring[qid];

        while (taskqueue_cancel(rx_ring->cmpl_tq, &rx_ring->cmpl_task, NULL) != 0)
                taskqueue_drain(rx_ring->cmpl_tq, &rx_ring->cmpl_task);

        taskqueue_free(rx_ring->cmpl_tq);

        /* Free buffer DMA maps, */
        for (int i = 0; i < rx_ring->ring_size; i++) {
                m_freem(rx_ring->rx_buffer_info[i].mbuf);
                rx_ring->rx_buffer_info[i].mbuf = NULL;
                bus_dmamap_unload(adapter->rx_buf_tag,
                    rx_ring->rx_buffer_info[i].map);
                bus_dmamap_destroy(adapter->rx_buf_tag,
                    rx_ring->rx_buffer_info[i].map);
        }

#if 0 /* XXX LRO */
        /* free LRO resources, */
        tcp_lro_free(&rx_ring->lro);
#endif

        /* free allocated memory */
        kfree(rx_ring->rx_buffer_info, M_DEVBUF);
        rx_ring->rx_buffer_info = NULL;

        kfree(rx_ring->free_rx_ids, M_DEVBUF);
        rx_ring->free_rx_ids = NULL;
}

/**
 * ena_setup_all_rx_resources - allocate all queues Rx resources
 * @adapter: network interface device structure
 *
 * Returns 0 on success, otherwise on failure.
 **/
static int
ena_setup_all_rx_resources(struct ena_adapter *adapter)
{
        int i, rc = 0;

        for (i = 0; i < adapter->num_queues; i++) {
                rc = ena_setup_rx_resources(adapter, i);
                if (rc != 0) {
                        device_printf(adapter->pdev,
                            "Allocation for Rx Queue %u failed\n", i);
                        goto err_setup_rx;
                }
        }
        return (0);

err_setup_rx:
        /* rewind the index freeing the rings as we go */
        while (i--)
                ena_free_rx_resources(adapter, i);
        return (rc);
}

/**
 * ena_free_all_rx_resources - Free Rx resources for all queues
 * @adapter: network interface device structure
 *
 * Free all receive software resources
 **/
static void
ena_free_all_rx_resources(struct ena_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_queues; i++)
                ena_free_rx_resources(adapter, i);
}

static inline int
ena_alloc_rx_mbuf(struct ena_adapter *adapter,
    struct ena_ring *rx_ring, struct ena_rx_buffer *rx_info)
{
        struct ena_com_buf *ena_buf;
        bus_dma_segment_t segs[1];
        int nsegs, error;
        int mlen;

        /* if previous allocated frag is not used */
        if (unlikely(rx_info->mbuf != NULL))
                return (0);

        /* Get mbuf using UMA allocator */
        rx_info->mbuf = m_getjcl(M_NOWAIT, MT_DATA, M_PKTHDR, MJUMPAGESIZE);

        if (unlikely(rx_info->mbuf == NULL)) {
#if 0 /* XXX swildner counters */
                counter_u64_add(rx_ring->rx_stats.mjum_alloc_fail, 1);
#endif
                rx_info->mbuf = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
                if (unlikely(rx_info->mbuf == NULL)) {
                        IFNET_STAT_INC(rx_ring->adapter->ifp, ierrors, 1);
#if 0 /* XXX swildner counters */
                        counter_u64_add(rx_ring->rx_stats.mbuf_alloc_fail, 1);
#endif
                        return (ENOMEM);
                }
                mlen = MCLBYTES;
        } else {
                mlen = MJUMPAGESIZE;
        }
        /* Set mbuf length*/
        rx_info->mbuf->m_pkthdr.len = rx_info->mbuf->m_len = mlen;

        /* Map packets for DMA */
        ena_trace(ENA_DBG | ENA_RSC | ENA_RXPTH,
            "Using tag %p for buffers' DMA mapping, mbuf %p len: %d",
            adapter->rx_buf_tag,rx_info->mbuf, rx_info->mbuf->m_len);
        error = bus_dmamap_load_mbuf_segment(adapter->rx_buf_tag, rx_info->map,
            rx_info->mbuf, segs, 1, &nsegs, BUS_DMA_NOWAIT);
        if (unlikely((error != 0) || (nsegs != 1))) {
                ena_trace(ENA_WARNING, "failed to map mbuf, error: %d, "
                    "nsegs: %d\n", error, nsegs);
                IFNET_STAT_INC(rx_ring->adapter->ifp, ierrors, 1);
#if 0 /* XXX swildner counters */
                counter_u64_add(rx_ring->rx_stats.dma_mapping_err, 1);
#endif
                goto exit;

        }

        bus_dmamap_sync(adapter->rx_buf_tag, rx_info->map, BUS_DMASYNC_PREREAD);

        ena_buf = &rx_info->ena_buf;
        ena_buf->paddr = segs[0].ds_addr;
        ena_buf->len = mlen;

        ena_trace(ENA_DBG | ENA_RSC | ENA_RXPTH,
            "ALLOC RX BUF: mbuf %p, rx_info %p, len %d, paddr %#jx\n",
            rx_info->mbuf, rx_info,ena_buf->len, (uintmax_t)ena_buf->paddr);

        return (0);

exit:
        m_freem(rx_info->mbuf);
        rx_info->mbuf = NULL;
        return (EFAULT);
}

static void
ena_free_rx_mbuf(struct ena_adapter *adapter, struct ena_ring *rx_ring,
    struct ena_rx_buffer *rx_info)
{

        if (rx_info->mbuf == NULL) {
                ena_trace(ENA_WARNING, "Trying to free unallocated buffer\n");
                return;
        }

        bus_dmamap_unload(adapter->rx_buf_tag, rx_info->map);
        m_freem(rx_info->mbuf);
        rx_info->mbuf = NULL;
}

/**
 * ena_refill_rx_bufs - Refills ring with descriptors
 * @rx_ring: the ring which we want to feed with free descriptors
 * @num: number of descriptors to refill
 * Refills the ring with newly allocated DMA-mapped mbufs for receiving
 **/
static int
ena_refill_rx_bufs(struct ena_ring *rx_ring, uint32_t num)
{
        struct ena_adapter *adapter = rx_ring->adapter;
        uint16_t next_to_use, req_id;
        uint32_t i;
        int rc;

        ena_trace(ENA_DBG | ENA_RXPTH | ENA_RSC, "refill qid: %d",
            rx_ring->qid);

        next_to_use = rx_ring->next_to_use;

        for (i = 0; i < num; i++) {
                struct ena_rx_buffer *rx_info;

                ena_trace(ENA_DBG | ENA_RXPTH | ENA_RSC,
                    "RX buffer - next to use: %d", next_to_use);

                req_id = rx_ring->free_rx_ids[next_to_use];
                rc = validate_rx_req_id(rx_ring, req_id);
                if (unlikely(rc != 0))
                        break;

                rx_info = &rx_ring->rx_buffer_info[req_id];

                rc = ena_alloc_rx_mbuf(adapter, rx_ring, rx_info);
                if (unlikely(rc != 0)) {
                        ena_trace(ENA_WARNING,
                            "failed to alloc buffer for rx queue %d\n",
                            rx_ring->qid);
                        break;
                }
                rc = ena_com_add_single_rx_desc(rx_ring->ena_com_io_sq,
                    &rx_info->ena_buf, req_id);
                if (unlikely(rc != 0)) {
                        ena_trace(ENA_WARNING,
                            "failed to add buffer for rx queue %d\n",
                            rx_ring->qid);
                        break;
                }
                next_to_use = ENA_RX_RING_IDX_NEXT(next_to_use,
                    rx_ring->ring_size);
        }

        if (unlikely(i < num)) {
                IFNET_STAT_INC(rx_ring->adapter->ifp, ierrors, 1);
#if 0 /* XXX swildner counters */
                counter_u64_add(rx_ring->rx_stats.refil_partial, 1);
#endif
                ena_trace(ENA_WARNING,
                     "refilled rx qid %d with only %d mbufs (from %d)\n",
                     rx_ring->qid, i, num);
        }

        if (likely(i != 0)) {
                wmb();
                ena_com_write_sq_doorbell(rx_ring->ena_com_io_sq);
        }
        rx_ring->next_to_use = next_to_use;
        return (i);
}

static void
ena_free_rx_bufs(struct ena_adapter *adapter, unsigned int qid)
{
        struct ena_ring *rx_ring = &adapter->rx_ring[qid];
        unsigned int i;

        for (i = 0; i < rx_ring->ring_size; i++) {
                struct ena_rx_buffer *rx_info = &rx_ring->rx_buffer_info[i];

                if (rx_info->mbuf != NULL)
                        ena_free_rx_mbuf(adapter, rx_ring, rx_info);
        }
}

/**
 * ena_refill_all_rx_bufs - allocate all queues Rx buffers
 * @adapter: network interface device structure
 *
 */
static void
ena_refill_all_rx_bufs(struct ena_adapter *adapter)
{
        struct ena_ring *rx_ring;
        int i, rc, bufs_num;

        for (i = 0; i < adapter->num_queues; i++) {
                rx_ring = &adapter->rx_ring[i];
                bufs_num = rx_ring->ring_size - 1;
                rc = ena_refill_rx_bufs(rx_ring, bufs_num);

                if (unlikely(rc != bufs_num))
                        ena_trace(ENA_WARNING, "refilling Queue %d failed. "
                            "Allocated %d buffers from: %d\n", i, rc, bufs_num);
        }
}

static void
ena_free_all_rx_bufs(struct ena_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_queues; i++)
                ena_free_rx_bufs(adapter, i);
}

/**
 * ena_free_tx_bufs - Free Tx Buffers per Queue
 * @adapter: network interface device structure
 * @qid: queue index
 **/
static void
ena_free_tx_bufs(struct ena_adapter *adapter, unsigned int qid)
{
        bool print_once = true;
        struct ena_ring *tx_ring = &adapter->tx_ring[qid];

        ENA_RING_MTX_LOCK(tx_ring);
        for (int i = 0; i < tx_ring->ring_size; i++) {
                struct ena_tx_buffer *tx_info = &tx_ring->tx_buffer_info[i];

                if (tx_info->mbuf == NULL)
                        continue;

                if (print_once) {
                        device_printf(adapter->pdev,
                            "free uncompleted tx mbuf qid %d idx 0x%x",
                            qid, i);
                        print_once = false;
                } else {
                        ena_trace(ENA_DBG,
                            "free uncompleted tx mbuf qid %d idx 0x%x",
                             qid, i);
                }

                bus_dmamap_unload(adapter->tx_buf_tag, tx_info->map);
                m_free(tx_info->mbuf);
                tx_info->mbuf = NULL;
        }
        ENA_RING_MTX_UNLOCK(tx_ring);
}

static void
ena_free_all_tx_bufs(struct ena_adapter *adapter)
{

        for (int i = 0; i < adapter->num_queues; i++)
                ena_free_tx_bufs(adapter, i);
}

static void
ena_destroy_all_tx_queues(struct ena_adapter *adapter)
{
        uint16_t ena_qid;
        int i;

        for (i = 0; i < adapter->num_queues; i++) {
                ena_qid = ENA_IO_TXQ_IDX(i);
                ena_com_destroy_io_queue(adapter->ena_dev, ena_qid);
        }
}

static void
ena_destroy_all_rx_queues(struct ena_adapter *adapter)
{
        uint16_t ena_qid;
        int i;

        for (i = 0; i < adapter->num_queues; i++) {
                ena_qid = ENA_IO_RXQ_IDX(i);
                ena_com_destroy_io_queue(adapter->ena_dev, ena_qid);
        }
}

static void
ena_destroy_all_io_queues(struct ena_adapter *adapter)
{
        ena_destroy_all_tx_queues(adapter);
        ena_destroy_all_rx_queues(adapter);
}

static inline int
validate_tx_req_id(struct ena_ring *tx_ring, uint16_t req_id)
{
        struct ena_adapter *adapter = tx_ring->adapter;
        struct ena_tx_buffer *tx_info = NULL;

        if (likely(req_id < tx_ring->ring_size)) {
                tx_info = &tx_ring->tx_buffer_info[req_id];
                if (tx_info->mbuf != NULL)
                        return (0);
        }

        if (tx_info->mbuf == NULL)
                device_printf(adapter->pdev,
                    "tx_info doesn't have valid mbuf\n");
        else
                device_printf(adapter->pdev, "Invalid req_id: %hu\n", req_id);

        IFNET_STAT_INC(tx_ring->adapter->ifp, oerrors, 1);
#if 0 /* XXX swildner counters */
        counter_u64_add(tx_ring->tx_stats.bad_req_id, 1);
#endif

        return (EFAULT);
}

static int
ena_create_io_queues(struct ena_adapter *adapter)
{
        struct ena_com_dev *ena_dev = adapter->ena_dev;
        struct ena_com_create_io_ctx ctx;
        struct ena_ring *ring;
        uint16_t ena_qid;
        uint32_t msix_vector;
        int rc, i;

        /* Create TX queues */
        for (i = 0; i < adapter->num_queues; i++) {
                msix_vector = ENA_IO_IRQ_IDX(i);
                ena_qid = ENA_IO_TXQ_IDX(i);
                ctx.mem_queue_type = ena_dev->tx_mem_queue_type;
                ctx.direction = ENA_COM_IO_QUEUE_DIRECTION_TX;
                ctx.queue_size = adapter->tx_ring_size;
                ctx.msix_vector = msix_vector;
                ctx.qid = ena_qid;
                rc = ena_com_create_io_queue(ena_dev, &ctx);
                if (rc != 0) {
                        device_printf(adapter->pdev,
                            "Failed to create io TX queue #%d rc: %d\n", i, rc);
                        goto err_tx;
                }
                ring = &adapter->tx_ring[i];
                rc = ena_com_get_io_handlers(ena_dev, ena_qid,
                    &ring->ena_com_io_sq,
                    &ring->ena_com_io_cq);
                if (rc != 0) {
                        device_printf(adapter->pdev,
                            "Failed to get TX queue handlers. TX queue num"
                            " %d rc: %d\n", i, rc);
                        ena_com_destroy_io_queue(ena_dev, ena_qid);
                        goto err_tx;
                }
        }

        /* Create RX queues */
        for (i = 0; i < adapter->num_queues; i++) {
                msix_vector = ENA_IO_IRQ_IDX(i);
                ena_qid = ENA_IO_RXQ_IDX(i);
                ctx.mem_queue_type = ENA_ADMIN_PLACEMENT_POLICY_HOST;
                ctx.direction = ENA_COM_IO_QUEUE_DIRECTION_RX;
                ctx.queue_size = adapter->rx_ring_size;
                ctx.msix_vector = msix_vector;
                ctx.qid = ena_qid;
                rc = ena_com_create_io_queue(ena_dev, &ctx);
                if (unlikely(rc != 0)) {
                        device_printf(adapter->pdev,
                            "Failed to create io RX queue[%d] rc: %d\n", i, rc);
                        goto err_rx;
                }

                ring = &adapter->rx_ring[i];
                rc = ena_com_get_io_handlers(ena_dev, ena_qid,
                    &ring->ena_com_io_sq,
                    &ring->ena_com_io_cq);
                if (unlikely(rc != 0)) {
                        device_printf(adapter->pdev,
                            "Failed to get RX queue handlers. RX queue num"
                            " %d rc: %d\n", i, rc);
                        ena_com_destroy_io_queue(ena_dev, ena_qid);
                        goto err_rx;
                }
        }

        return (0);

err_rx:
        while (i--)
                ena_com_destroy_io_queue(ena_dev, ENA_IO_RXQ_IDX(i));
        i = adapter->num_queues;
err_tx:
        while (i--)
                ena_com_destroy_io_queue(ena_dev, ENA_IO_TXQ_IDX(i));

        return (ENXIO);
}

/**
 * ena_tx_cleanup - clear sent packets and corresponding descriptors
 * @tx_ring: ring for which we want to clean packets
 *
 * Once packets are sent, we ask the device in a loop for no longer used
 * descriptors. We find the related mbuf chain in a map (index in an array)
 * and free it, then update ring state.
 * This is performed in "endless" loop, updating ring pointers every
 * TX_COMMIT. The first check of free descriptor is performed before the actual
 * loop, then repeated at the loop end.
 **/
static int
ena_tx_cleanup(struct ena_ring *tx_ring)
{
        struct ena_adapter *adapter;
        struct ena_com_io_cq* io_cq;
        uint16_t next_to_clean;
        uint16_t req_id;
        uint16_t ena_qid;
        unsigned int total_done = 0;
        int rc;
        int commit = TX_COMMIT;
        int budget = TX_BUDGET;
        int work_done;

        adapter = tx_ring->que->adapter;
        ena_qid = ENA_IO_TXQ_IDX(tx_ring->que->id);
        io_cq = &adapter->ena_dev->io_cq_queues[ena_qid];
        next_to_clean = tx_ring->next_to_clean;

        do {
                struct ena_tx_buffer *tx_info;
                struct mbuf *mbuf;

                rc = ena_com_tx_comp_req_id_get(io_cq, &req_id);
                if (unlikely(rc != 0))
                        break;

                rc = validate_tx_req_id(tx_ring, req_id);
                if (unlikely(rc != 0))
                        break;

                tx_info = &tx_ring->tx_buffer_info[req_id];

                mbuf = tx_info->mbuf;

                tx_info->mbuf = NULL;
                timevalclear(&tx_info->timestamp);

                if (likely(tx_info->num_of_bufs != 0)) {
                        /* Map is no longer required */
                        bus_dmamap_unload(adapter->tx_buf_tag, tx_info->map);
                }

                ena_trace(ENA_DBG | ENA_TXPTH, "tx: q %d mbuf %p completed",
                    tx_ring->qid, mbuf);

                m_freem(mbuf);

                total_done += tx_info->tx_descs;

                tx_ring->free_tx_ids[next_to_clean] = req_id;
                next_to_clean = ENA_TX_RING_IDX_NEXT(next_to_clean,
                    tx_ring->ring_size);

                if (unlikely(--commit == 0)) {
                        commit = TX_COMMIT;
                        /* update ring state every TX_COMMIT descriptor */
                        tx_ring->next_to_clean = next_to_clean;
                        ena_com_comp_ack(
                            &adapter->ena_dev->io_sq_queues[ena_qid],
                            total_done);
                        ena_com_update_dev_comp_head(io_cq);
                        total_done = 0;
                }
        } while (likely(--budget));

        work_done = TX_BUDGET - budget;

        ena_trace(ENA_DBG | ENA_TXPTH, "tx: q %d done. total pkts: %d",
        tx_ring->qid, work_done);

        /* If there is still something to commit update ring state */
        if (likely(commit != TX_COMMIT)) {
                tx_ring->next_to_clean = next_to_clean;
                ena_com_comp_ack(&adapter->ena_dev->io_sq_queues[ena_qid],
                    total_done);
                ena_com_update_dev_comp_head(io_cq);
        }

        return (work_done);
}

static void
ena_rx_hash_mbuf(struct ena_ring *rx_ring, struct ena_com_rx_ctx *ena_rx_ctx,
    struct mbuf *mbuf)
{
        struct ena_adapter *adapter = rx_ring->adapter;

        if (likely(adapter->rss_support)) {
                //mbuf->m_pkthdr.flowid = ena_rx_ctx->hash;
                m_sethash(mbuf, ena_rx_ctx->hash);

#if 0 /* XXX rsstype doesn't seem to be needed by the network stack, we will only supply the hash. */
                if (ena_rx_ctx->frag &&
                    (ena_rx_ctx->l3_proto != ENA_ETH_IO_L3_PROTO_UNKNOWN)) {
                        M_HASHTYPE_SET(mbuf, M_HASHTYPE_OPAQUE_HASH);
                        return;
                }

                switch (ena_rx_ctx->l3_proto) {
                case ENA_ETH_IO_L3_PROTO_IPV4:
                        switch (ena_rx_ctx->l4_proto) {
                        case ENA_ETH_IO_L4_PROTO_TCP:
                                M_HASHTYPE_SET(mbuf, M_HASHTYPE_RSS_TCP_IPV4);
                                break;
                        case ENA_ETH_IO_L4_PROTO_UDP:
                                M_HASHTYPE_SET(mbuf, M_HASHTYPE_RSS_UDP_IPV4);
                                break;
                        default:
                                M_HASHTYPE_SET(mbuf, M_HASHTYPE_RSS_IPV4);
                        }
                        break;
                case ENA_ETH_IO_L3_PROTO_IPV6:
                        switch (ena_rx_ctx->l4_proto) {
                        case ENA_ETH_IO_L4_PROTO_TCP:
                                M_HASHTYPE_SET(mbuf, M_HASHTYPE_RSS_TCP_IPV6);
                                break;
                        case ENA_ETH_IO_L4_PROTO_UDP:
                                M_HASHTYPE_SET(mbuf, M_HASHTYPE_RSS_UDP_IPV6);
                                break;
                        default:
                                M_HASHTYPE_SET(mbuf, M_HASHTYPE_RSS_IPV6);
                        }
                        break;
                case ENA_ETH_IO_L3_PROTO_UNKNOWN:
                        M_HASHTYPE_SET(mbuf, M_HASHTYPE_NONE);
                        break;
                default:
                        M_HASHTYPE_SET(mbuf, M_HASHTYPE_OPAQUE_HASH);
                }
#endif
        } else {
                //mbuf->m_pkthdr.flowid = rx_ring->qid;
                //M_HASHTYPE_SET(mbuf, M_HASHTYPE_NONE);
                m_sethash(mbuf, rx_ring->qid);
        }
}

/**
 * ena_rx_mbuf - assemble mbuf from descriptors
 * @rx_ring: ring for which we want to clean packets
 * @ena_bufs: buffer info
 * @ena_rx_ctx: metadata for this packet(s)
 * @next_to_clean: ring pointer, will be updated only upon success
 *
 **/
static struct mbuf*
ena_rx_mbuf(struct ena_ring *rx_ring, struct ena_com_rx_buf_info *ena_bufs,
    struct ena_com_rx_ctx *ena_rx_ctx, uint16_t *next_to_clean)
{
        struct mbuf *mbuf;
        struct ena_rx_buffer *rx_info;
        struct ena_adapter *adapter;
        unsigned int descs = ena_rx_ctx->descs;
        uint16_t ntc, len, req_id, buf = 0;

        ntc = *next_to_clean;
        adapter = rx_ring->adapter;
        rx_info = &rx_ring->rx_buffer_info[ntc];

        if (unlikely(rx_info->mbuf == NULL)) {
                device_printf(adapter->pdev, "NULL mbuf in rx_info");
                return (NULL);
        }

        len = ena_bufs[buf].len;
        req_id = ena_bufs[buf].req_id;
        rx_info = &rx_ring->rx_buffer_info[req_id];

        ena_trace(ENA_DBG | ENA_RXPTH, "rx_info %p, mbuf %p, paddr %jx",
            rx_info, rx_info->mbuf, (uintmax_t)rx_info->ena_buf.paddr);

        mbuf = rx_info->mbuf;
        mbuf->m_flags |= M_PKTHDR;
        mbuf->m_pkthdr.len = len;
        mbuf->m_len = len;
        mbuf->m_pkthdr.rcvif = rx_ring->que->adapter->ifp;

        /* Fill mbuf with hash key and it's interpretation for optimization */
        ena_rx_hash_mbuf(rx_ring, ena_rx_ctx, mbuf);

        ena_trace(ENA_DBG | ENA_RXPTH, "rx mbuf 0x%p, flags=0x%x, len: %d",
            mbuf, mbuf->m_flags, mbuf->m_pkthdr.len);

        /* DMA address is not needed anymore, unmap it */
        bus_dmamap_unload(rx_ring->adapter->rx_buf_tag, rx_info->map);

        rx_info->mbuf = NULL;
        rx_ring->free_rx_ids[ntc] = req_id;
        ntc = ENA_RX_RING_IDX_NEXT(ntc, rx_ring->ring_size);

        /*
         * While we have more than 1 descriptors for one rcvd packet, append
         * other mbufs to the main one
         */
        while (--descs) {
                ++buf;
                len = ena_bufs[buf].len;
                req_id = ena_bufs[buf].req_id;
                rx_info = &rx_ring->rx_buffer_info[req_id];

                if (unlikely(rx_info->mbuf == NULL)) {
                        device_printf(adapter->pdev, "NULL mbuf in rx_info");
                        /*
                         * If one of the required mbufs was not allocated yet,
                         * we can break there.
                         * All earlier used descriptors will be reallocated
                         * later and not used mbufs can be reused.
                         * The next_to_clean pointer will not be updated in case
                         * of an error, so caller should advance it manually
                         * in error handling routine to keep it up to date
                         * with hw ring.
                         */
                        m_freem(mbuf);
                        return (NULL);
                }

                if (unlikely(m_append(mbuf, len, rx_info->mbuf->m_data) == 0)) {
                        IFNET_STAT_INC(rx_ring->adapter->ifp, ierrors, 1);
#if 0 /* XXX swildner counters */
                        counter_u64_add(rx_ring->rx_stats.mbuf_alloc_fail, 1);
#endif
                        ena_trace(ENA_WARNING, "Failed to append Rx mbuf %p",
                            mbuf);
                }

                ena_trace(ENA_DBG | ENA_RXPTH,
                    "rx mbuf updated. len %d", mbuf->m_pkthdr.len);

                /* Free already appended mbuf, it won't be useful anymore */
                bus_dmamap_unload(rx_ring->adapter->rx_buf_tag, rx_info->map);
                m_freem(rx_info->mbuf);
                rx_info->mbuf = NULL;

                rx_ring->free_rx_ids[ntc] = req_id;
                ntc = ENA_RX_RING_IDX_NEXT(ntc, rx_ring->ring_size);
        }

        *next_to_clean = ntc;

        return (mbuf);
}

/**
 * ena_rx_checksum - indicate in mbuf if hw indicated a good cksum
 **/
static inline void
ena_rx_checksum(struct ena_ring *rx_ring, struct ena_com_rx_ctx *ena_rx_ctx,
    struct mbuf *mbuf)
{

        /* if IP and error */
        if (unlikely((ena_rx_ctx->l3_proto == ENA_ETH_IO_L3_PROTO_IPV4) &&
            ena_rx_ctx->l3_csum_err)) {
                /* ipv4 checksum error */
                mbuf->m_pkthdr.csum_flags = 0;
                IFNET_STAT_INC(rx_ring->adapter->ifp, ierrors, 1);
#if 0 /* XXX swildner counters */
                counter_u64_add(rx_ring->rx_stats.bad_csum, 1);
#endif
                ena_trace(ENA_DBG, "RX IPv4 header checksum error");
                return;
        }

        /* if TCP/UDP */
        if ((ena_rx_ctx->l4_proto == ENA_ETH_IO_L4_PROTO_TCP) ||
            (ena_rx_ctx->l4_proto == ENA_ETH_IO_L4_PROTO_UDP)) {
                if (ena_rx_ctx->l4_csum_err) {
                        /* TCP/UDP checksum error */
                        mbuf->m_pkthdr.csum_flags = 0;
                        IFNET_STAT_INC(rx_ring->adapter->ifp, ierrors, 1);
#if 0 /* XXX swildner counters */
                        counter_u64_add(rx_ring->rx_stats.bad_csum, 1);
#endif
                        ena_trace(ENA_DBG, "RX L4 checksum error");
                } else {
                        mbuf->m_pkthdr.csum_flags = CSUM_IP_CHECKED;
                        mbuf->m_pkthdr.csum_flags |= CSUM_IP_VALID;
                }
        }
}

static void
ena_deferred_rx_cleanup(void *arg, int pending)
{
        struct ena_ring *rx_ring = arg;
        int budget = CLEAN_BUDGET;

        ENA_RING_MTX_LOCK(rx_ring);
        /*
         * If deferred task was executed, perform cleanup of all awaiting
         * descs (or until given budget is depleted to avoid infinite loop).
         */
        while (likely(budget--)) {
                if (ena_rx_cleanup(rx_ring) == 0)
                        break;
        }
        ENA_RING_MTX_UNLOCK(rx_ring);
}

/**
 * ena_rx_cleanup - handle rx irq
 * @arg: ring for which irq is being handled
 **/
static int
ena_rx_cleanup(struct ena_ring *rx_ring)
{
        struct ena_adapter *adapter;
        struct mbuf *mbuf;
        struct ena_com_rx_ctx ena_rx_ctx;
        struct ena_com_io_cq* io_cq;
        struct ena_com_io_sq* io_sq;
        if_t ifp;
        uint16_t ena_qid;
        uint16_t next_to_clean;
        uint32_t refill_required;
        uint32_t refill_threshold;
        uint32_t do_if_input = 0;
        unsigned int qid;
        int rc, i;
        int budget = RX_BUDGET;

        adapter = rx_ring->que->adapter;
        ifp = adapter->ifp;
        qid = rx_ring->que->id;
        ena_qid = ENA_IO_RXQ_IDX(qid);
        io_cq = &adapter->ena_dev->io_cq_queues[ena_qid];
        io_sq = &adapter->ena_dev->io_sq_queues[ena_qid];
        next_to_clean = rx_ring->next_to_clean;

        ena_trace(ENA_DBG, "rx: qid %d", qid);

        do {
                ena_rx_ctx.ena_bufs = rx_ring->ena_bufs;
                ena_rx_ctx.max_bufs = adapter->max_rx_sgl_size;
                ena_rx_ctx.descs = 0;
                rc = ena_com_rx_pkt(io_cq, io_sq, &ena_rx_ctx);

                if (unlikely(rc != 0))
                        goto error;

                if (unlikely(ena_rx_ctx.descs == 0))
                        break;

                ena_trace(ENA_DBG | ENA_RXPTH, "rx: q %d got packet from ena. "
                    "descs #: %d l3 proto %d l4 proto %d hash: %x",
                    rx_ring->qid, ena_rx_ctx.descs, ena_rx_ctx.l3_proto,
                    ena_rx_ctx.l4_proto, ena_rx_ctx.hash);

                /* Receive mbuf from the ring */
                mbuf = ena_rx_mbuf(rx_ring, rx_ring->ena_bufs,
                    &ena_rx_ctx, &next_to_clean);

                /* Exit if we failed to retrieve a buffer */
                if (unlikely(mbuf == NULL)) {
                        for (i = 0; i < ena_rx_ctx.descs; ++i) {
                                rx_ring->free_rx_ids[next_to_clean] =
                                    rx_ring->ena_bufs[i].req_id;
                                next_to_clean =
                                    ENA_RX_RING_IDX_NEXT(next_to_clean,
                                    rx_ring->ring_size);

                        }
                        break;
                }

                /*
                 * XXX Removed IFCAP_RXCSUM_IPV6 check because DragonFly
                 *     does not seem to support it
                 */
                if ((ifp->if_capenable & IFCAP_RXCSUM) != 0) {
                        ena_rx_checksum(rx_ring, &ena_rx_ctx, mbuf);
                }

#if 0 /* XXX swildner counters */
                counter_enter();
                counter_u64_add_protected(rx_ring->rx_stats.bytes,
                    mbuf->m_pkthdr.len);
                counter_u64_add_protected(adapter->hw_stats.rx_bytes,
                    mbuf->m_pkthdr.len);
                counter_exit();
#endif
                /*
                 * LRO is only for IP/TCP packets and TCP checksum of the packet
                 * should be computed by hardware.
                 */
                do_if_input = 1;
#if 0 /* XXX LRO */
                if (((ifp->if_capenable & IFCAP_LRO) != 0)  &&
                    ((mbuf->m_pkthdr.csum_flags & CSUM_IP_VALID) != 0) &&
                    (ena_rx_ctx.l4_proto == ENA_ETH_IO_L4_PROTO_TCP)) {
                        /*
                         * Send to the stack if:
                         *  - LRO not enabled, or
                         *  - no LRO resources, or
                         *  - lro enqueue fails
                         */
                        if ((rx_ring->lro.lro_cnt != 0) &&
                            (tcp_lro_rx(&rx_ring->lro, mbuf, 0) == 0))
                                        do_if_input = 0;
                }
#endif
                if (do_if_input != 0) {
                        ena_trace(ENA_DBG | ENA_RXPTH,
                            "calling if_input() with mbuf %p", mbuf);
                        ENA_RING_MTX_UNLOCK(rx_ring);
                        (*ifp->if_input)(ifp, mbuf, NULL, -1);
                        ENA_RING_MTX_LOCK(rx_ring);
                }

                IFNET_STAT_INC(ifp, ipackets, 1);
#if 0 /* XXX swildner counters */
                counter_enter();
                counter_u64_add_protected(rx_ring->rx_stats.cnt, 1);
                counter_u64_add_protected(adapter->hw_stats.rx_packets, 1);
                counter_exit();
#endif
        } while (--budget);

        rx_ring->next_to_clean = next_to_clean;

        refill_required = ena_com_free_desc(io_sq);
        refill_threshold = rx_ring->ring_size / ENA_RX_REFILL_THRESH_DIVIDER;

        if (refill_required > refill_threshold) {
                ena_com_update_dev_comp_head(rx_ring->ena_com_io_cq);
                ena_refill_rx_bufs(rx_ring, refill_required);
        }

#if 0 /* XXX LRO */
        tcp_lro_flush_all(&rx_ring->lro);
#endif

        return (RX_BUDGET - budget);

error:
        IFNET_STAT_INC(rx_ring->adapter->ifp, ierrors, 1);
#if 0 /* XXX swildner counters */
        counter_u64_add(rx_ring->rx_stats.bad_desc_num, 1);
#endif
        return (RX_BUDGET - budget);
}

/*********************************************************************
 *
 *  MSIX & Interrupt Service routine
 *
 **********************************************************************/

/**
 * ena_handle_msix - MSIX Interrupt Handler for admin/async queue
 * @arg: interrupt number
 **/
static void
ena_intr_msix_mgmnt(void *arg)
{
        struct ena_adapter *adapter = (struct ena_adapter *)arg;

        ena_com_admin_q_comp_intr_handler(adapter->ena_dev);
        if (likely(adapter->running))
                ena_com_aenq_intr_handler(adapter->ena_dev, arg);
}

/**
 * ena_handle_msix - MSIX Interrupt Handler for Tx/Rx
 * @arg: interrupt number
 **/
static void
ena_handle_msix(void *arg)
{
        struct ena_que  *que = arg;
        struct ena_adapter *adapter = que->adapter;
        if_t ifp = adapter->ifp;
        struct ena_ring *tx_ring;
        struct ena_ring *rx_ring;
        struct ena_com_io_cq* io_cq;
        struct ena_eth_io_intr_reg intr_reg;
        int qid, ena_qid;
        int txc, rxc, i;

        if (unlikely((ifp->if_flags & IFF_RUNNING) == 0))
                return;

        ena_trace(ENA_DBG, "MSI-X TX/RX routine");

        tx_ring = que->tx_ring;
        rx_ring = que->rx_ring;
        qid = que->id;
        ena_qid = ENA_IO_TXQ_IDX(qid);
        io_cq = &adapter->ena_dev->io_cq_queues[ena_qid];

        for (i = 0; i < CLEAN_BUDGET; ++i) {
                /*
                 * If lock cannot be acquired, then deferred cleanup task was
                 * being executed and rx ring is being cleaned up in
                 * another thread.
                 */
                if (likely(ENA_RING_MTX_TRYLOCK(rx_ring) != 0)) {
                        rxc = ena_rx_cleanup(rx_ring);
                        ENA_RING_MTX_UNLOCK(rx_ring);
                } else {
                        rxc = 0;
                }

                /* Protection from calling ena_tx_cleanup from ena_start_xmit */
                ENA_RING_MTX_LOCK(tx_ring);
                txc = ena_tx_cleanup(tx_ring);
                ENA_RING_MTX_UNLOCK(tx_ring);

                if (unlikely((ifp->if_flags & IFF_RUNNING) == 0))
                        return;

                if ((txc != TX_BUDGET) && (rxc != RX_BUDGET))
                       break;
        }

        /* Signal that work is done and unmask interrupt */
        ena_com_update_intr_reg(&intr_reg,
            RX_IRQ_INTERVAL,
            TX_IRQ_INTERVAL,
            true);
        ena_com_unmask_intr(io_cq, &intr_reg);
}

static int
ena_enable_msix(struct ena_adapter *adapter)
{
        device_t dev = adapter->pdev;
        int msix_vecs;
        int error, i, rc = 0;

        /* Reserved the max msix vectors we might need */
        msix_vecs = ENA_MAX_MSIX_VEC(adapter->num_queues);

        adapter->msix_entries = kmalloc(msix_vecs * sizeof(struct msix_entry),
            M_DEVBUF, M_WAITOK | M_ZERO);

        ena_trace(ENA_DBG, "trying to enable MSI-X, vectors: %d", msix_vecs);

        for (i = 0; i < msix_vecs; i++) {
                adapter->msix_entries[i].entry = i;
                /* Vectors must start from 1 */
                adapter->msix_entries[i].vector = i + 1;
        }

        error = pci_setup_msix(dev);
        if (error) {
                device_printf(dev, "pci_setup_msix() failed\n");
                goto err_msix_free;
        }

        adapter->msix_vecs = msix_vecs;
        adapter->msix_enabled = true;

        return (0);

err_msix_free:
        kfree(adapter->msix_entries, M_DEVBUF);
        adapter->msix_entries = NULL;

        return (rc);
}

static void
ena_setup_mgmnt_intr(struct ena_adapter *adapter)
{

        ksnprintf(adapter->irq_tbl[ENA_MGMNT_IRQ_IDX].name,
            ENA_IRQNAME_SIZE, "ena-mgmnt@pci:%s",
            device_get_nameunit(adapter->pdev));
        /*
         * Handler is NULL on purpose, it will be set
         * when mgmnt interrupt is acquired
         */
        adapter->irq_tbl[ENA_MGMNT_IRQ_IDX].handler = NULL;
        adapter->irq_tbl[ENA_MGMNT_IRQ_IDX].data = adapter;
        adapter->irq_tbl[ENA_MGMNT_IRQ_IDX].vector =
            adapter->msix_entries[ENA_MGMNT_IRQ_IDX].vector;
}

static void
ena_setup_io_intr(struct ena_adapter *adapter)
{
        static int last_bind_cpu = -1;
        int irq_idx;

        for (int i = 0; i < adapter->num_queues; i++) {
                irq_idx = ENA_IO_IRQ_IDX(i);

                ksnprintf(adapter->irq_tbl[irq_idx].name, ENA_IRQNAME_SIZE,
                    "%s-TxRx-%d", device_get_nameunit(adapter->pdev), i);
                adapter->irq_tbl[irq_idx].handler = ena_handle_msix;
                adapter->irq_tbl[irq_idx].data = &adapter->que[i];
                adapter->irq_tbl[irq_idx].vector =
                    adapter->msix_entries[irq_idx].vector;
                ena_trace(ENA_INFO | ENA_IOQ, "ena_setup_io_intr vector: %d\n",
                    adapter->msix_entries[irq_idx].vector);
#ifdef  RSS
                adapter->que[i].cpu = adapter->irq_tbl[irq_idx].cpu =
                    rss_getcpu(i % rss_getnumbuckets());
#else
                /*
                 * We still want to bind rings to the corresponding cpu
                 * using something similar to the RSS round-robin technique.
                 *
                 * XXX It seems that this can be removed since DragonFly has
                 *     native support for RSS. DragonFly also does not have
                 *     support for CPU_FIRST or CPU_NEXT.
                 */

                if (last_bind_cpu < 0)
                        last_bind_cpu = (last_bind_cpu + 1) % ncpus;
                adapter->que[i].cpu = adapter->irq_tbl[irq_idx].cpu =
                    last_bind_cpu;
                last_bind_cpu = (last_bind_cpu + 1) % ncpus;
#endif
        }
}

static int
ena_request_mgmnt_irq(struct ena_adapter *adapter)
{
        struct ena_irq *irq;
        unsigned long flags;
        int error, rc, rcc;

        flags = RF_ACTIVE | RF_SHAREABLE;

        irq = &adapter->irq_tbl[ENA_MGMNT_IRQ_IDX];

        error = pci_alloc_msix_vector(adapter->pdev, 0, &irq->vector, 0);
        if (error) {
                device_printf(adapter->pdev, "Could not initialize MGMNT MSI-X Vector on cpu0\n");
                return (ENXIO);
        }

        irq->res = bus_alloc_resource_any(adapter->pdev, SYS_RES_IRQ,
            &irq->vector, flags);

        if (unlikely(irq->res == NULL)) {
                device_printf(adapter->pdev, "could not allocate "
                    "irq vector: %d\n", irq->vector);
                pci_release_msix_vector(adapter->pdev, irq->vector);
                return (ENXIO);
        }

        rc = bus_activate_resource(adapter->pdev, SYS_RES_IRQ,
            irq->vector, irq->res);
        if (unlikely(rc != 0)) {
                device_printf(adapter->pdev, "could not activate "
                    "irq vector: %d\n", irq->vector);
                goto err_res_free;
        }

        rc = bus_setup_intr(adapter->pdev, irq->res,
            INTR_MPSAFE, ena_intr_msix_mgmnt,
            irq->data, &irq->cookie, NULL);
        if (unlikely(rc != 0)) {
                device_printf(adapter->pdev, "failed to register "
                    "interrupt handler for irq %ju: %d\n",
                    rman_get_start(irq->res), rc);
                goto err_res_free;
        }
        irq->requested = true;

        return (rc);

err_res_free:
        ena_trace(ENA_INFO | ENA_ADMQ, "releasing resource for irq %d\n",
            irq->vector);
        rcc = bus_release_resource(adapter->pdev, SYS_RES_IRQ,
            irq->vector, irq->res);
        pci_release_msix_vector(adapter->pdev, irq->vector);
        if (unlikely(rcc != 0))
                device_printf(adapter->pdev, "dev has no parent while "
                    "releasing res for irq: %d\n", irq->vector);
        irq->res = NULL;

        return (rc);
}

static int
ena_request_io_irq(struct ena_adapter *adapter)
{
        struct ena_irq *irq;
        unsigned long flags = 0;
        int rc = 0, i, rcc, error;

        if (unlikely(adapter->msix_enabled == 0)) {
                device_printf(adapter->pdev,
                    "failed to request I/O IRQ: MSI-X is not enabled\n");
                return (EINVAL);
        } else {
                flags = RF_ACTIVE | RF_SHAREABLE;
        }

        for (i = ENA_IO_IRQ_FIRST_IDX; i < adapter->msix_vecs; i++) {
                irq = &adapter->irq_tbl[i];

                if (unlikely(irq->requested))
                        continue;

                error = pci_alloc_msix_vector(adapter->pdev, i, &irq->vector, irq->cpu);
                if (error) {
                        device_printf(adapter->pdev, "Unable to allocated MSI-X %d on cpu%d\n", i, irq->cpu);
                        goto err;
                }

                irq->res = bus_alloc_resource_any(adapter->pdev, SYS_RES_IRQ,
                    &irq->vector, flags);
                if (unlikely(irq->res == NULL)) {
                        device_printf(adapter->pdev, "could not allocate "
                            "irq vector: %d\n", irq->vector);
                        goto err;
                }


                /*
                 * TODO: Might need to setup desc and use irq->name as the
                 *       value
                 */
                rc = bus_setup_intr(adapter->pdev, irq->res,
                    INTR_MPSAFE,
                    irq->handler, irq->data, &irq->cookie, NULL);
                 if (unlikely(rc != 0)) {
                        device_printf(adapter->pdev, "failed to register "
                            "interrupt handler for irq %ju: %d\n",
                            rman_get_start(irq->res), rc);
                        goto err;
                }
                irq->requested = true;

#ifdef  RSS
                ena_trace(ENA_INFO, "queue %d - RSS bucket %d\n",
                    i - ENA_IO_IRQ_FIRST_IDX, irq->cpu);
#else
                ena_trace(ENA_INFO, "queue %d - cpu %d\n",
                    i - ENA_IO_IRQ_FIRST_IDX, irq->cpu);
#endif
        }

        return (rc);

err:

        for (; i >= ENA_IO_IRQ_FIRST_IDX; i--) {
                irq = &adapter->irq_tbl[i];
                rcc = 0;

                /* Once we entered err: section and irq->requested is true we
                   free both intr and resources */
                if (irq->requested)
                        rcc = bus_teardown_intr(adapter->pdev, irq->res, irq->cookie);
                if (unlikely(rcc != 0))
                        device_printf(adapter->pdev, "could not release"
                            " irq: %d, error: %d\n", irq->vector, rcc);

                /* If we entred err: section without irq->requested set we know
                   it was bus_alloc_resource_any() that needs cleanup, provided
                   res is not NULL. In case res is NULL no work in needed in
                   this iteration */
                rcc = 0;
                if (irq->res != NULL) {
                        rcc = bus_release_resource(adapter->pdev, SYS_RES_IRQ,
                            irq->vector, irq->res);
                        pci_release_msix_vector(adapter->pdev, irq->vector);
                }
                if (unlikely(rcc != 0))
                        device_printf(adapter->pdev, "dev has no parent while "
                            "releasing res for irq: %d\n", irq->vector);
                irq->requested = false;
                irq->res = NULL;
        }

        return (rc);
}

static void
ena_free_mgmnt_irq(struct ena_adapter *adapter)
{
        struct ena_irq *irq;
        int rc;

        irq = &adapter->irq_tbl[ENA_MGMNT_IRQ_IDX];
        if (irq->requested) {
                ena_trace(ENA_INFO | ENA_ADMQ, "tear down irq: %d\n",
                    irq->vector);
                rc = bus_teardown_intr(adapter->pdev, irq->res, irq->cookie);
                if (unlikely(rc != 0))
                        device_printf(adapter->pdev, "failed to tear "
                            "down irq: %d\n", irq->vector);
                irq->requested = 0;
        }

        if (irq->res != NULL) {
                ena_trace(ENA_INFO | ENA_ADMQ, "release resource irq: %d\n",
                    irq->vector);
                rc = bus_release_resource(adapter->pdev, SYS_RES_IRQ,
                    irq->vector, irq->res);
                pci_release_msix_vector(adapter->pdev, irq->vector);
                irq->res = NULL;
                if (unlikely(rc != 0))
                        device_printf(adapter->pdev, "dev has no parent while "
                            "releasing res for irq: %d\n", irq->vector);
        }
}

static void
ena_free_io_irq(struct ena_adapter *adapter)
{
        struct ena_irq *irq;
        int rc;

        for (int i = ENA_IO_IRQ_FIRST_IDX; i < adapter->msix_vecs; i++) {
                irq = &adapter->irq_tbl[i];
                if (irq->requested) {
                        ena_trace(ENA_INFO | ENA_IOQ, "tear down irq: %d\n",
                            irq->vector);
                        rc = bus_teardown_intr(adapter->pdev, irq->res,
                            irq->cookie);
                        if (unlikely(rc != 0)) {
                                device_printf(adapter->pdev, "failed to tear "
                                    "down irq: %d\n", irq->vector);
                        }
                        irq->requested = 0;
                }

                if (irq->res != NULL) {
                        ena_trace(ENA_INFO | ENA_IOQ, "release resource irq: %d\n",
                            irq->vector);
                        rc = bus_release_resource(adapter->pdev, SYS_RES_IRQ,
                            irq->vector, irq->res);
                        pci_release_msix_vector(adapter->pdev, irq->vector);
                        irq->res = NULL;
                        if (unlikely(rc != 0)) {
                                device_printf(adapter->pdev, "dev has no parent"
                                    " while releasing res for irq: %d\n",
                                    irq->vector);
                        }
                }
        }
}

static void
ena_free_irqs(struct ena_adapter* adapter)
{

        ena_free_io_irq(adapter);
        ena_free_mgmnt_irq(adapter);
        ena_disable_msix(adapter);
}

static void
ena_disable_msix(struct ena_adapter *adapter)
{

        pci_release_msi(adapter->pdev);

        adapter->msix_vecs = 0;
        kfree(adapter->msix_entries, M_DEVBUF);
        adapter->msix_entries = NULL;
}

static void
ena_unmask_all_io_irqs(struct ena_adapter *adapter)
{
        struct ena_com_io_cq* io_cq;
        struct ena_eth_io_intr_reg intr_reg;
        uint16_t ena_qid;
        int i;

        /* Unmask interrupts for all queues */
        for (i = 0; i < adapter->num_queues; i++) {
                ena_qid = ENA_IO_TXQ_IDX(i);
                io_cq = &adapter->ena_dev->io_cq_queues[ena_qid];
                ena_com_update_intr_reg(&intr_reg, 0, 0, true);
                ena_com_unmask_intr(io_cq, &intr_reg);
        }
}

/* Configure the Rx forwarding */
static int
ena_rss_configure(struct ena_adapter *adapter)
{
        struct ena_com_dev *ena_dev = adapter->ena_dev;
        int rc;

        /* Set indirect table */
        rc = ena_com_indirect_table_set(ena_dev);
        if (unlikely((rc != 0) && (rc != EOPNOTSUPP)))
                return (rc);

        /* Configure hash function (if supported) */
        rc = ena_com_set_hash_function(ena_dev);
        if (unlikely((rc != 0) && (rc != EOPNOTSUPP)))
                return (rc);

        /* Configure hash inputs (if supported) */
        rc = ena_com_set_hash_ctrl(ena_dev);
        if (unlikely((rc != 0) && (rc != EOPNOTSUPP)))
                return (rc);

        return (0);
}

static int
ena_up_complete(struct ena_adapter *adapter)
{
        int rc;

        if (likely(adapter->rss_support)) {
                rc = ena_rss_configure(adapter);
                if (rc != 0)
                        return (rc);
        }

        rc = ena_change_mtu(adapter->ifp, adapter->ifp->if_mtu);
        if (unlikely(rc != 0))
                return (rc);

        ena_refill_all_rx_bufs(adapter);
#if 0 /* XXX swildner counters */
        ena_reset_counters((counter_u64_t *)&adapter->hw_stats,
            sizeof(adapter->hw_stats));
#endif

        return (0);
}

static int
ena_up(struct ena_adapter *adapter)
{
        int rc = 0;

        if (unlikely(device_is_attached(adapter->pdev) == 0)) {
                device_printf(adapter->pdev, "device is not attached!\n");
                return (ENXIO);
        }

        if (unlikely(!adapter->running)) {
                device_printf(adapter->pdev, "device is not running!\n");
                return (ENXIO);
        }

        if (!adapter->up) {
                device_printf(adapter->pdev, "device is going UP\n");

                /* setup interrupts for IO queues */
                ena_setup_io_intr(adapter);
                rc = ena_request_io_irq(adapter);
                if (unlikely(rc != 0)) {
                        ena_trace(ENA_ALERT, "err_req_irq");
                        goto err_req_irq;
                }

                /* allocate transmit descriptors */
                rc = ena_setup_all_tx_resources(adapter);
                if (unlikely(rc != 0)) {
                        ena_trace(ENA_ALERT, "err_setup_tx");
                        goto err_setup_tx;
                }

                /* allocate receive descriptors */
                rc = ena_setup_all_rx_resources(adapter);
                if (unlikely(rc != 0)) {
                        ena_trace(ENA_ALERT, "err_setup_rx");
                        goto err_setup_rx;
                }

                /* create IO queues for Rx & Tx */
                rc = ena_create_io_queues(adapter);
                if (unlikely(rc != 0)) {
                        ena_trace(ENA_ALERT,
                            "create IO queues failed");
                        goto err_io_que;
                }

                if (unlikely(adapter->link_status)) {
                        adapter->ifp->if_link_state = LINK_STATE_UP;
                        if_link_state_change(adapter->ifp);
                }

                rc = ena_up_complete(adapter);
                if (unlikely(rc != 0))
                        goto err_up_complete;

#if 0 /* XXX swildner counters */
                counter_u64_add(adapter->dev_stats.interface_up, 1);
#endif

                ena_update_hwassist(adapter);

                adapter->ifp->if_flags |= IFF_RUNNING;
                ifq_clr_oactive(&adapter->ifp->if_snd);

                callout_reset(&adapter->timer_service, hz,
                    ena_timer_service, (void *)adapter);

                adapter->up = true;

                ena_unmask_all_io_irqs(adapter);
        }

        return (0);

err_up_complete:
        ena_destroy_all_io_queues(adapter);
err_io_que:
        ena_free_all_rx_resources(adapter);
err_setup_rx:
        ena_free_all_tx_resources(adapter);
err_setup_tx:
        ena_free_io_irq(adapter);
err_req_irq:
        return (rc);
}

#if 0 /* XXX swildner counters */
static uint64_t
ena_get_counter(if_t ifp, ift_counter cnt)
{
        struct ena_adapter *adapter;
        struct ena_hw_stats *stats;

        adapter = ifp->if_softc;
        stats = &adapter->hw_stats;

        switch (cnt) {
        case IFCOUNTER_IPACKETS:
                return (counter_u64_fetch(stats->rx_packets));
        case IFCOUNTER_OPACKETS:
                return (counter_u64_fetch(stats->tx_packets));
        case IFCOUNTER_IBYTES:
                return (counter_u64_fetch(stats->rx_bytes));
        case IFCOUNTER_OBYTES:
                return (counter_u64_fetch(stats->tx_bytes));
        case IFCOUNTER_IQDROPS:
                return (counter_u64_fetch(stats->rx_drops));
        default:
                return (if_get_counter_default(ifp, cnt));
        }
}
#endif

static int
ena_media_change(if_t ifp)
{
        /* Media Change is not supported by firmware */
        return (0);
}

static void
ena_media_status(if_t ifp, struct ifmediareq *ifmr)
{
        struct ena_adapter *adapter = ifp->if_softc;
        ena_trace(ENA_DBG, "enter");

        lockmgr(&adapter->global_lock, LK_EXCLUSIVE);

        ifmr->ifm_status = IFM_AVALID;
        ifmr->ifm_active = IFM_ETHER;

        if (!adapter->link_status) {
                lockmgr(&adapter->global_lock, LK_RELEASE);
                ena_trace(ENA_INFO, "link_status = false");
                return;
        }

        ifmr->ifm_status |= IFM_ACTIVE;
        ifmr->ifm_active |= IFM_10G_T | IFM_FDX;

        lockmgr(&adapter->global_lock, LK_RELEASE);
}

static void
ena_init(void *arg)
{
        struct ena_adapter *adapter = (struct ena_adapter *)arg;

        if (!adapter->up) {
                lockmgr(&adapter->ioctl_lock, LK_EXCLUSIVE);
                ena_up(adapter);
                lockmgr(&adapter->ioctl_lock, LK_RELEASE);
        }
}

static int
ena_ioctl(if_t ifp, u_long command, caddr_t data, struct ucred *cred)
{
        struct ena_adapter *adapter;
        struct ifreq *ifr;
        int rc;

        adapter = ifp->if_softc;
        ifr = (struct ifreq *)data;

        /*
         * Acquiring lock to prevent from running up and down routines parallel.
         */
        rc = 0;
        switch (command) {
        case SIOCSIFMTU:
                lockmgr(&adapter->ioctl_lock, LK_EXCLUSIVE);
                ena_down(adapter);

                ena_change_mtu(ifp, ifr->ifr_mtu);

                rc = ena_up(adapter);
                lockmgr(&adapter->ioctl_lock, LK_RELEASE);
                break;

        case SIOCSIFFLAGS:
                if ((ifp->if_flags & IFF_UP) != 0) {
                        if ((ifp->if_flags & IFF_RUNNING) != 0) {
                                if ((ifp->if_flags & (IFF_PROMISC |
                                    IFF_ALLMULTI)) != 0) {
                                        device_printf(adapter->pdev,
                                            "ioctl promisc/allmulti\n");
                                }
                        } else {
                                lockmgr(&adapter->ioctl_lock, LK_EXCLUSIVE);
                                rc = ena_up(adapter);
                                lockmgr(&adapter->ioctl_lock, LK_RELEASE);
                        }
                } else {
                        if ((ifp->if_flags & IFF_RUNNING) != 0) {
                                lockmgr(&adapter->ioctl_lock, LK_EXCLUSIVE);
                                ena_down(adapter);
                                lockmgr(&adapter->ioctl_lock, LK_RELEASE);
                        }
                }
                break;

        case SIOCADDMULTI:
        case SIOCDELMULTI:
                break;

        case SIOCSIFMEDIA:
        case SIOCGIFMEDIA:
                rc = ifmedia_ioctl(ifp, ifr, &adapter->media, command);
                break;

        case SIOCSIFCAP:
                {
                        int reinit = 0;

                        if (ifr->ifr_reqcap != ifp->if_capenable) {
                                ifp->if_capenable = ifr->ifr_reqcap;
                                reinit = 1;
                        }

                        if ((reinit != 0) &&
                            ((ifp->if_flags & IFF_RUNNING) != 0)) {
                                lockmgr(&adapter->ioctl_lock, LK_EXCLUSIVE);
                                ena_down(adapter);
                                rc = ena_up(adapter);
                                lockmgr(&adapter->ioctl_lock, LK_RELEASE);
                        }
                }

                break;
        default:
                rc = ether_ioctl(ifp, command, data);
                break;
        }

        return (rc);
}

static int
ena_get_dev_offloads(struct ena_com_dev_get_features_ctx *feat)
{
        int caps = 0;

        if ((feat->offload.tx &
            (ENA_ADMIN_FEATURE_OFFLOAD_DESC_TX_L4_IPV4_CSUM_FULL_MASK |
            ENA_ADMIN_FEATURE_OFFLOAD_DESC_TX_L4_IPV4_CSUM_PART_MASK |
                ENA_ADMIN_FEATURE_OFFLOAD_DESC_TX_L3_CSUM_IPV4_MASK)) != 0)
                caps |= IFCAP_TXCSUM;

        if ((feat->offload.tx &
            (ENA_ADMIN_FEATURE_OFFLOAD_DESC_TX_L4_IPV6_CSUM_FULL_MASK |
            ENA_ADMIN_FEATURE_OFFLOAD_DESC_TX_L4_IPV6_CSUM_PART_MASK)) != 0)
                caps |= IFCAP_TXCSUM;

        if ((feat->offload.tx &
            ENA_ADMIN_FEATURE_OFFLOAD_DESC_TSO_IPV4_MASK) != 0)
                caps |= IFCAP_TSO4;

        if ((feat->offload.tx &
            ENA_ADMIN_FEATURE_OFFLOAD_DESC_TSO_IPV6_MASK) != 0)
                caps |= IFCAP_TSO6;

        if ((feat->offload.rx_supported &
            (ENA_ADMIN_FEATURE_OFFLOAD_DESC_RX_L4_IPV4_CSUM_MASK |
            ENA_ADMIN_FEATURE_OFFLOAD_DESC_RX_L3_CSUM_IPV4_MASK)) != 0)
                caps |= IFCAP_RXCSUM;

#if 0
        if ((feat->offload.rx_supported &
            ENA_ADMIN_FEATURE_OFFLOAD_DESC_RX_L4_IPV6_CSUM_MASK) != 0)
                caps |= IFCAP_RXCSUM_IPV6;
#endif
#if 0 /* XXX LRO */
        caps |= IFCAP_LRO;
#endif
        caps |= IFCAP_JUMBO_MTU;

        return (caps);
}

static void
ena_update_host_info(struct ena_admin_host_info *host_info, if_t ifp)
{

        host_info->supported_network_features[0] =
            (uint32_t)ifp->if_capabilities;
}

static void
ena_update_hwassist(struct ena_adapter *adapter)
{
        if_t ifp = adapter->ifp;
        uint32_t feat = adapter->tx_offload_cap;
        int cap = ifp->if_capenable;
        int flags = 0;

        ifp->if_hwassist = 0;

        if ((cap & IFCAP_TXCSUM) != 0) {
                if ((feat &
                    ENA_ADMIN_FEATURE_OFFLOAD_DESC_TX_L3_CSUM_IPV4_MASK) != 0)
                        flags |= CSUM_IP;
                if ((feat &
                    (ENA_ADMIN_FEATURE_OFFLOAD_DESC_TX_L4_IPV4_CSUM_FULL_MASK |
                    ENA_ADMIN_FEATURE_OFFLOAD_DESC_TX_L4_IPV4_CSUM_PART_MASK)) != 0)
                        flags |= CSUM_UDP | CSUM_TCP;
        }

#if 0
        if ((cap & IFCAP_TXCSUM_IPV6) != 0)
                flags |= CSUM_IP6_UDP | CSUM_IP6_TCP;
#endif

        if ((cap & IFCAP_TSO4) != 0 || (cap & IFCAP_TSO6) != 0)
                flags |= CSUM_TSO;

        ifp->if_hwassist |= flags;
}

static int
ena_setup_ifnet(device_t pdev, struct ena_adapter *adapter,
    struct ena_com_dev_get_features_ctx *feat)
{
        if_t ifp;
        int caps = 0;

        ifp = adapter->ifp = if_alloc(IFT_ETHER);
        if (unlikely(ifp == NULL)) {
                ena_trace(ENA_ALERT, "can not allocate ifnet structure\n");
                return (ENXIO);
        }
        if_initname(ifp, device_get_name(pdev), device_get_unit(pdev));
        ifp->if_softc = adapter;

        ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;

        ifp->if_init = ena_init;
        ifp->if_start = ena_start_xmit;
        ifp->if_ioctl = ena_ioctl;
#if 0 /* XXX swildner counter */
        if_setgetcounterfn(ifp, ena_get_counter);
#endif

        ifq_set_maxlen(&ifp->if_snd, adapter->tx_ring_size);
        ifq_set_ready(&ifp->if_snd);
        ifp->if_mtu = ETHERMTU;
        ifp->if_baudrate = 0;
        /* Zeroize capabilities... */
        ifp->if_capabilities = 0;
        ifp->if_capenable = 0;
        /* check hardware support */
        caps = ena_get_dev_offloads(feat);
        /* ... and set them */
        //if_setcapabilitiesbit(ifp, caps, 0);
        ((struct ifnet *)ifp)->if_capabilities |= caps;
        ((struct ifnet *)ifp)->if_capabilities &= ~0;

        /* TSO parameters */
        //ifp->if_hw_tsomax = ENA_TSO_MAXSIZE -
        //    (ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN);
        ifp->if_tsolen = adapter->max_tx_sgl_size - 1;
        //ifp->if_hw_tsomaxsegsize = ENA_TSO_MAXSIZE;

        ifp->if_hdrlen = sizeof(struct ether_vlan_header);
        ifp->if_capenable= ifp->if_capabilities;

        /*
         * Specify the media types supported by this adapter and register
         * callbacks to update media and link information
         */
        ifmedia_init(&adapter->media, IFM_IMASK,
            ena_media_change, ena_media_status);
        ifmedia_add(&adapter->media, IFM_ETHER | IFM_AUTO, 0, NULL);
        ifmedia_set(&adapter->media, IFM_ETHER | IFM_AUTO);

        ether_ifattach(ifp, adapter->mac_addr, NULL);

        return (0);
}

static void
ena_down(struct ena_adapter *adapter)
{
        int rc;

        if (adapter->up) {
                device_printf(adapter->pdev, "device is going DOWN\n");

                callout_drain(&adapter->timer_service);

                adapter->up = false;
                ifq_set_oactive(&adapter->ifp->if_snd);
                adapter->ifp->if_flags &= ~IFF_RUNNING;

                ena_free_io_irq(adapter);

                if (adapter->trigger_reset) {
                        rc = ena_com_dev_reset(adapter->ena_dev,
                            adapter->reset_reason);
                        if (unlikely(rc != 0))
                                device_printf(adapter->pdev,
                                    "Device reset failed\n");
                }

                ena_destroy_all_io_queues(adapter);

                ena_free_all_tx_bufs(adapter);
                ena_free_all_rx_bufs(adapter);
                ena_free_all_tx_resources(adapter);
                ena_free_all_rx_resources(adapter);

#if 0 /* XXX swildner counters */
                counter_u64_add(adapter->dev_stats.interface_down, 1);
#endif
        }
}

static void
ena_tx_csum(struct ena_com_tx_ctx *ena_tx_ctx, struct mbuf *mbuf)
{
        struct ena_com_tx_meta *ena_meta;
        struct ether_vlan_header *eh;
        u32 mss;
        bool offload;
        uint16_t etype;
        int ehdrlen;
        struct ip *ip;
        int iphlen;
        struct tcphdr *th;

        offload = false;
        ena_meta = &ena_tx_ctx->ena_meta;
        mss = mbuf->m_pkthdr.tso_segsz;

        if (mss != 0)
                offload = true;

        if ((mbuf->m_pkthdr.csum_flags & CSUM_TSO) != 0)
                offload = true;

        if ((mbuf->m_pkthdr.csum_flags & CSUM_OFFLOAD) != 0)
                offload = true;

        if (!offload) {
                ena_tx_ctx->meta_valid = 0;
                return;
        }

        /* Determine where frame payload starts. */
        eh = mtod(mbuf, struct ether_vlan_header *);
        if (eh->evl_encap_proto == htons(ETHERTYPE_VLAN)) {
                etype = ntohs(eh->evl_proto);
                ehdrlen = ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN;
        } else {
                etype = ntohs(eh->evl_encap_proto);
                ehdrlen = ETHER_HDR_LEN;
        }

        ip = (struct ip *)(mbuf->m_data + ehdrlen);
        iphlen = ip->ip_hl << 2;
        th = (struct tcphdr *)((caddr_t)ip + iphlen);

        if ((mbuf->m_pkthdr.csum_flags & CSUM_IP) != 0) {
                ena_tx_ctx->l3_csum_enable = 1;
        }
        if ((mbuf->m_pkthdr.csum_flags & CSUM_TSO) != 0) {
                ena_tx_ctx->tso_enable = 1;
                ena_meta->l4_hdr_len = (th->th_off);
        }

        switch (etype) {
        case ETHERTYPE_IP:
                ena_tx_ctx->l3_proto = ENA_ETH_IO_L3_PROTO_IPV4;
                if ((ip->ip_off & htons(IP_DF)) != 0)
                        ena_tx_ctx->df = 1;
                break;
        case ETHERTYPE_IPV6:
                ena_tx_ctx->l3_proto = ENA_ETH_IO_L3_PROTO_IPV6;

        default:
                break;
        }

        if (ip->ip_p == IPPROTO_TCP) {
                ena_tx_ctx->l4_proto = ENA_ETH_IO_L4_PROTO_TCP;
                if ((mbuf->m_pkthdr.csum_flags &
                    CSUM_TCP) != 0)
                        ena_tx_ctx->l4_csum_enable = 1;
                else
                        ena_tx_ctx->l4_csum_enable = 0;
        } else if (ip->ip_p == IPPROTO_UDP) {
                ena_tx_ctx->l4_proto = ENA_ETH_IO_L4_PROTO_UDP;
                if ((mbuf->m_pkthdr.csum_flags &
                    CSUM_UDP) != 0)
                        ena_tx_ctx->l4_csum_enable = 1;
                else
                        ena_tx_ctx->l4_csum_enable = 0;
        } else {
                ena_tx_ctx->l4_proto = ENA_ETH_IO_L4_PROTO_UNKNOWN;
                ena_tx_ctx->l4_csum_enable = 0;
        }

        ena_meta->mss = mss;
        ena_meta->l3_hdr_len = iphlen;
        ena_meta->l3_hdr_offset = ehdrlen;
        ena_tx_ctx->meta_valid = 1;
}

static int
ena_check_and_collapse_mbuf(struct ena_ring *tx_ring, struct mbuf **mbuf)
{
        struct ena_adapter *adapter;
        struct mbuf *collapsed_mbuf;
        int num_frags;

        adapter = tx_ring->adapter;
        num_frags = ena_mbuf_count(*mbuf);

        /* One segment must be reserved for configuration descriptor. */
        if (num_frags < adapter->max_tx_sgl_size)
                return (0);
#if 0 /* XXX swildner counters */
        counter_u64_add(tx_ring->tx_stats.collapse, 1);
#endif

        collapsed_mbuf = m_defrag(*mbuf, M_NOWAIT);
        if (unlikely(collapsed_mbuf == NULL)) {
                IFNET_STAT_INC(tx_ring->adapter->ifp, oerrors, 1);
#if 0 /* XXX swildner counters */
                counter_u64_add(tx_ring->tx_stats.collapse_err, 1);
#endif
                return (ENOMEM);
        }

        /* If mbuf was collapsed succesfully, original mbuf is released. */
        *mbuf = collapsed_mbuf;

        return (0);
}

static int
ena_xmit_mbuf(struct ena_ring *tx_ring, struct mbuf **mbuf)
{
        struct ena_adapter *adapter;
        struct ena_tx_buffer *tx_info;
        struct ena_com_tx_ctx ena_tx_ctx;
        struct ena_com_dev *ena_dev;
        struct ena_com_buf *ena_buf;
        struct ena_com_io_sq* io_sq;
        bus_dma_segment_t segs[ENA_BUS_DMA_SEGS];
        void *push_hdr;
        uint16_t next_to_use;
        uint16_t req_id;
        uint16_t push_len;
        uint16_t ena_qid;
        uint32_t len, nsegs, header_len;
        int i, rc;
        int nb_hw_desc;

        ena_qid = ENA_IO_TXQ_IDX(tx_ring->que->id);
        adapter = tx_ring->que->adapter;
        ena_dev = adapter->ena_dev;
        io_sq = &ena_dev->io_sq_queues[ena_qid];

        //tx_ring is just used to grab the adapter
        rc = ena_check_and_collapse_mbuf(tx_ring, mbuf);
        if (unlikely(rc != 0)) {
                ena_trace(ENA_WARNING,
                    "Failed to collapse mbuf! err: %d", rc);
                return (rc);
        }

        next_to_use = tx_ring->next_to_use;
        req_id = tx_ring->free_tx_ids[next_to_use];
        tx_info = &tx_ring->tx_buffer_info[req_id];

        tx_info->mbuf = *mbuf;
        tx_info->num_of_bufs = 0;

        ena_buf = tx_info->bufs;
        len = (*mbuf)->m_len;

        ena_trace(ENA_DBG | ENA_TXPTH, "Tx: %d bytes", (*mbuf)->m_pkthdr.len);

        push_len = 0;
        header_len = min_t(uint32_t, len, tx_ring->tx_max_header_size);
        push_hdr = NULL;

        rc = bus_dmamap_load_mbuf_segment(adapter->tx_buf_tag, tx_info->map,
            *mbuf, segs, adapter->max_tx_sgl_size, &nsegs, BUS_DMA_NOWAIT);

        if (unlikely((rc != 0) || (nsegs == 0))) {
                ena_trace(ENA_WARNING,
                    "dmamap load failed! err: %d nsegs: %d", rc, nsegs);
                IFNET_STAT_INC(tx_ring->adapter->ifp, oerrors, 1);
#if 0 /* XXX swildner counters */
                counter_u64_add(tx_ring->tx_stats.dma_mapping_err, 1);
#endif
                tx_info->mbuf = NULL;
                if (rc == ENOMEM)
                        return (ENA_COM_NO_MEM);
                else
                        return (ENA_COM_INVAL);
        }

        for (i = 0; i < nsegs; i++) {
                ena_buf->len = segs[i].ds_len;
                ena_buf->paddr = segs[i].ds_addr;
                ena_buf++;
        }
        tx_info->num_of_bufs = nsegs;

        memset(&ena_tx_ctx, 0x0, sizeof(struct ena_com_tx_ctx));
        ena_tx_ctx.ena_bufs = tx_info->bufs;
        ena_tx_ctx.push_header = push_hdr;
        ena_tx_ctx.num_bufs = tx_info->num_of_bufs;
        ena_tx_ctx.req_id = req_id;
        ena_tx_ctx.header_len = header_len;

        /* Set flags and meta data */
        ena_tx_csum(&ena_tx_ctx, *mbuf);
        /* Prepare the packet's descriptors and send them to device */
        rc = ena_com_prepare_tx(io_sq, &ena_tx_ctx, &nb_hw_desc);
        if (unlikely(rc != 0)) {
                device_printf(adapter->pdev, "failed to prepare tx bufs\n");
                IFNET_STAT_INC(tx_ring->adapter->ifp, oerrors, 1);
#if 0 /* XXX swildner counters */
                counter_u64_add(tx_ring->tx_stats.prepare_ctx_err, 1);
#endif
                goto dma_error;
        }

        IFNET_STAT_INC(tx_ring->adapter->ifp, opackets, 1);
#if 0 /* XXX swildner counters */
        counter_enter();
        counter_u64_add_protected(tx_ring->tx_stats.cnt, 1);
        counter_u64_add_protected(tx_ring->tx_stats.bytes,
            (*mbuf)->m_pkthdr.len);

        counter_u64_add_protected(adapter->hw_stats.tx_packets, 1);
        counter_u64_add_protected(adapter->hw_stats.tx_bytes,
            (*mbuf)->m_pkthdr.len);
        counter_exit();
#endif

        tx_info->tx_descs = nb_hw_desc;
        getmicrouptime(&tx_info->timestamp);
        tx_info->print_once = true;

        tx_ring->next_to_use = ENA_TX_RING_IDX_NEXT(next_to_use,
            tx_ring->ring_size);

        bus_dmamap_sync(adapter->tx_buf_tag, tx_info->map,
            BUS_DMASYNC_PREWRITE);

        return (0);

dma_error:
        tx_info->mbuf = NULL;
        bus_dmamap_unload(adapter->tx_buf_tag, tx_info->map);

        return (rc);
}

static void
ena_start_xmit(struct ifnet *ifp, struct ifaltq_subque *ifsq)
{
        /*
         * TODO: Might need to initialize an ena_ring with the
         *       ifaltq_subque in it
         */
        struct ena_adapter *adapter = ifp->if_softc;
        struct ena_com_io_sq *io_sq;
        struct ena_ring *tx_ring;
        int ena_qid;
        int acum_pkts = 0;
        int ret = 0;

        if (unlikely((adapter->ifp->if_flags & IFF_RUNNING) == 0) ||
            ifsq_is_oactive(ifsq)) {
                return;
        }

        /* Check is link_active and some other shit. If it is, purge. */

#if 0
        if (unlikely(!adapter->link_status))
                return;
#endif

        io_sq = NULL;
        tx_ring = NULL;

        while (!ifsq_is_empty(ifsq)) {
                struct mbuf *m_head;
                int i;

                //Grab head from mbuf list
                m_head = ifsq_dequeue(ifsq);
                if (m_head == NULL)
                        break;

                //pick the associated tx_ring based on hash
                i = m_head->m_pkthdr.hash % adapter->num_queues;

                tx_ring = &adapter->tx_ring[i];
                ENA_RING_MTX_LOCK(tx_ring);
                ena_qid = ENA_IO_TXQ_IDX(tx_ring->que->id);
                io_sq = &adapter->ena_dev->io_sq_queues[ena_qid];

                if (unlikely(!ena_com_sq_have_enough_space(io_sq, ENA_TX_CLEANUP_THRESHOLD)))
                        ena_tx_cleanup(tx_ring);

                if (unlikely((ret = ena_xmit_mbuf(tx_ring, &m_head)) != 0)) {
                        if (ret == ENA_COM_NO_MEM) {
                                /* XXX put mbuf back on queue */
                        } else if (ret == ENA_COM_NO_SPACE) {
                                /* XXX put mbuf back on queue */
                        } else {
                                m_freem(m_head);
                                /* XXX advance mbuf queue aka move it forward? */
                        }
                        ENA_RING_MTX_UNLOCK(tx_ring);
                        break;
                }

                //advance mbuf queue, might already be handled by dequeue

#if 0
                // dillon - wtf is this doing here?
                // NOT SURE WHAT TO DO WITH THIS CODE
                if (unlikely((adapter->ifp->if_flags & IFF_RUNNING) == 0))
                        return; // break here, not return. tx_ring locked
#endif

                acum_pkts++;

                ENA_RING_MTX_UNLOCK(tx_ring);
                BPF_MTAP(adapter->ifp, m_head);

                if (unlikely(acum_pkts == DB_THRESHOLD)) {
                        acum_pkts = 0;
                        wmb();
                        /* Trigger the dma engine */
                        ena_com_write_sq_doorbell(io_sq);
#if 0 /* XXX swildner counters */
                        counter_u64_add(tx_ring->tx_stats.doorbells, 1);
#endif
                }

        }

        if (likely(acum_pkts != 0)) {
                wmb();
                /* Trigger the dma engine */
                ena_com_write_sq_doorbell(io_sq);
#if 0 /* XXX swildner counters */
                counter_u64_add(tx_ring->tx_stats.doorbells, 1);
#endif
        }

        if (io_sq &&
            !ena_com_sq_have_enough_space(io_sq, ENA_TX_CLEANUP_THRESHOLD)) {
                ENA_RING_MTX_LOCK(tx_ring);
                ena_tx_cleanup(tx_ring);
                ENA_RING_MTX_UNLOCK(tx_ring);
        }
}

static int
ena_calc_io_queue_num(struct ena_adapter *adapter,
    struct ena_com_dev_get_features_ctx *get_feat_ctx)
{
        int io_sq_num, io_cq_num, io_queue_num;

        io_sq_num = get_feat_ctx->max_queues.max_sq_num;
        io_cq_num = get_feat_ctx->max_queues.max_cq_num;

        io_queue_num = min_t(int, ncpus, ENA_MAX_NUM_IO_QUEUES);
        io_queue_num = min_t(int, io_queue_num, io_sq_num);
        io_queue_num = min_t(int, io_queue_num, io_cq_num);
        /* 1 IRQ for for mgmnt and 1 IRQ for each TX/RX pair */
        io_queue_num = min_t(int, io_queue_num,
            pci_msix_count(adapter->pdev) - 1);
#ifdef  RSS
        io_queue_num = min_t(int, io_queue_num, rss_getnumbuckets());
#endif

        return (io_queue_num);
}

static int
ena_calc_queue_size(struct ena_adapter *adapter, uint16_t *max_tx_sgl_size,
    uint16_t *max_rx_sgl_size, struct ena_com_dev_get_features_ctx *feat)
{
        uint32_t queue_size = ENA_DEFAULT_RING_SIZE;
        uint32_t v;
        uint32_t q;

        queue_size = min_t(uint32_t, queue_size,
            feat->max_queues.max_cq_depth);
        queue_size = min_t(uint32_t, queue_size,
            feat->max_queues.max_sq_depth);

        /* round down to the nearest power of 2 */
        v = queue_size;
        while (v != 0) {
                if (powerof2(queue_size) != 0)
                        break;
                v /= 2;
                q = rounddown2(queue_size, v);
                if (q != 0) {
                        queue_size = q;
                        break;
                }
        }

        if (unlikely(queue_size == 0)) {
                device_printf(adapter->pdev, "Invalid queue size\n");
                return (ENA_COM_FAULT);
        }

        *max_tx_sgl_size = min_t(uint16_t, ENA_PKT_MAX_BUFS,
            feat->max_queues.max_packet_tx_descs);
        *max_rx_sgl_size = min_t(uint16_t, ENA_PKT_MAX_BUFS,
            feat->max_queues.max_packet_rx_descs);

        return (queue_size);
}

static int
ena_rss_init_default(struct ena_adapter *adapter)
{
        struct ena_com_dev *ena_dev = adapter->ena_dev;
        device_t dev = adapter->pdev;
        int qid, rc, i;

        rc = ena_com_rss_init(ena_dev, ENA_RX_RSS_TABLE_LOG_SIZE);
        if (unlikely(rc != 0)) {
                device_printf(dev, "Cannot init indirect table\n");
                return (rc);
        }

        for (i = 0; i < ENA_RX_RSS_TABLE_SIZE; i++) {
#ifdef  RSS
                qid = rss_get_indirection_to_bucket(i);
                qid = qid % adapter->num_queues;
#else
                qid = i % adapter->num_queues;
#endif
                rc = ena_com_indirect_table_fill_entry(ena_dev, i,
                    ENA_IO_RXQ_IDX(qid));
                if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
                        device_printf(dev, "Cannot fill indirect table\n");
                        goto err_rss_destroy;
                }
        }

        rc = ena_com_fill_hash_function(ena_dev, ENA_ADMIN_CRC32, NULL,
            ENA_HASH_KEY_SIZE, 0xFFFFFFFF);
        if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
                device_printf(dev, "Cannot fill hash function\n");
                goto err_rss_destroy;
        }

        rc = ena_com_set_default_hash_ctrl(ena_dev);
        if (unlikely((rc != 0) && (rc != EOPNOTSUPP))) {
                device_printf(dev, "Cannot fill hash control\n");
                goto err_rss_destroy;
        }

        return (0);

err_rss_destroy:
        ena_com_rss_destroy(ena_dev);
        return (rc);
}

static void
ena_rss_init_default_deferred(void *arg)
{
        struct ena_adapter *adapter;
        devclass_t dc;
        int max;
        int rc;

        dc = devclass_find("ena");
        if (unlikely(dc == NULL)) {
                ena_trace(ENA_ALERT, "No devclass ena\n");
                return;
        }

        max = devclass_get_maxunit(dc);
        while (max-- >= 0) {
                adapter = devclass_get_softc(dc, max);
                if (adapter != NULL) {
                        rc = ena_rss_init_default(adapter);
                        adapter->rss_support = true;
                        if (unlikely(rc != 0)) {
                                device_printf(adapter->pdev,
                                    "WARNING: RSS was not properly initialized,"
                                    " it will affect bandwidth\n");
                                adapter->rss_support = false;
                        }
                }
        }
}
SYSINIT(ena_rss_init, SI_SUB_KICK_SCHEDULER, SI_ORDER_SECOND, ena_rss_init_default_deferred, NULL);

static void
ena_config_host_info(struct ena_com_dev *ena_dev)
{
        struct ena_admin_host_info *host_info;
        int rc;

        /* Allocate only the host info */
        rc = ena_com_allocate_host_info(ena_dev);
        if (unlikely(rc != 0)) {
                ena_trace(ENA_ALERT, "Cannot allocate host info\n");
                return;
        }

        host_info = ena_dev->host_attr.host_info;

        host_info->os_type = ENA_ADMIN_OS_FREEBSD;
        host_info->kernel_ver = osreldate;

        ksprintf(host_info->kernel_ver_str, "%d", osreldate);
        host_info->os_dist = 0;
        strncpy(host_info->os_dist_str, osrelease,
            sizeof(host_info->os_dist_str) - 1);

        host_info->driver_version =
                (DRV_MODULE_VER_MAJOR) |
                (DRV_MODULE_VER_MINOR << ENA_ADMIN_HOST_INFO_MINOR_SHIFT) |
                (DRV_MODULE_VER_SUBMINOR << ENA_ADMIN_HOST_INFO_SUB_MINOR_SHIFT);

        rc = ena_com_set_host_attributes(ena_dev);
        if (unlikely(rc != 0)) {
                if (rc == EOPNOTSUPP)
                        ena_trace(ENA_WARNING, "Cannot set host attributes\n");
                else
                        ena_trace(ENA_ALERT, "Cannot set host attributes\n");

                goto err;
        }

        return;

err:
        ena_com_delete_host_info(ena_dev);
}

static int
ena_device_init(struct ena_adapter *adapter, device_t pdev,
    struct ena_com_dev_get_features_ctx *get_feat_ctx, int *wd_active)
{
        struct ena_com_dev* ena_dev = adapter->ena_dev;
        bool readless_supported;
        uint32_t aenq_groups;
        int dma_width;
        int rc;

        rc = ena_com_mmio_reg_read_request_init(ena_dev);
        if (unlikely(rc != 0)) {
                device_printf(pdev, "failed to init mmio read less\n");
                return (rc);
        }

        /*
         * The PCIe configuration space revision id indicate if mmio reg
         * read is disabled
         */
        readless_supported = !(pci_get_revid(pdev) & ENA_MMIO_DISABLE_REG_READ);
        ena_com_set_mmio_read_mode(ena_dev, readless_supported);

        rc = ena_com_dev_reset(ena_dev, ENA_REGS_RESET_NORMAL);
        if (unlikely(rc != 0)) {
                device_printf(pdev, "Can not reset device\n");
                goto err_mmio_read_less;
        }

        rc = ena_com_validate_version(ena_dev);
        if (unlikely(rc != 0)) {
                device_printf(pdev, "device version is too low\n");
                goto err_mmio_read_less;
        }

        dma_width = ena_com_get_dma_width(ena_dev);
        if (unlikely(dma_width < 0)) {
                device_printf(pdev, "Invalid dma width value %d", dma_width);
                rc = dma_width;
                goto err_mmio_read_less;
        }
        adapter->dma_width = dma_width;

        /* ENA admin level init */
        rc = ena_com_admin_init(ena_dev, &aenq_handlers, true);
        if (unlikely(rc != 0)) {
                device_printf(pdev,
                    "Can not initialize ena admin queue with device\n");
                goto err_mmio_read_less;
        }

        /*
         * To enable the msix interrupts the driver needs to know the number
         * of queues. So the driver uses polling mode to retrieve this
         * information
         */
        ena_com_set_admin_polling_mode(ena_dev, true);

        ena_config_host_info(ena_dev);

        /* Get Device Attributes */
        rc = ena_com_get_dev_attr_feat(ena_dev, get_feat_ctx);
        if (unlikely(rc != 0)) {
                device_printf(pdev,
                    "Cannot get attribute for ena device rc: %d\n", rc);
                goto err_admin_init;
        }

        aenq_groups = BIT(ENA_ADMIN_LINK_CHANGE) | BIT(ENA_ADMIN_KEEP_ALIVE);

        aenq_groups &= get_feat_ctx->aenq.supported_groups;
        rc = ena_com_set_aenq_config(ena_dev, aenq_groups);
        if (unlikely(rc != 0)) {
                device_printf(pdev, "Cannot configure aenq groups rc: %d\n", rc);
                goto err_admin_init;
        }

        *wd_active = !!(aenq_groups & BIT(ENA_ADMIN_KEEP_ALIVE));

        return (0);

err_admin_init:
        ena_com_delete_host_info(ena_dev);
        ena_com_admin_destroy(ena_dev);
err_mmio_read_less:
        ena_com_mmio_reg_read_request_destroy(ena_dev);

        return (rc);
}

static int ena_enable_msix_and_set_admin_interrupts(struct ena_adapter *adapter,
    int io_vectors)
{
        struct ena_com_dev *ena_dev = adapter->ena_dev;
        int rc;

        rc = ena_enable_msix(adapter);
        if (unlikely(rc != 0)) {
                device_printf(adapter->pdev, "Error with MSI-X enablement\n");
                return (rc);
        }

        ena_setup_mgmnt_intr(adapter);

        rc = ena_request_mgmnt_irq(adapter);
        if (unlikely(rc != 0)) {
                device_printf(adapter->pdev, "Cannot setup mgmnt queue intr\n");
                goto err_disable_msix;
        }

        pci_enable_msix(adapter->pdev);

        ena_com_set_admin_polling_mode(ena_dev, false);

        ena_com_admin_aenq_enable(ena_dev);

        return (0);

err_disable_msix:
        ena_disable_msix(adapter);

        return (rc);
}

/* Function called on ENA_ADMIN_KEEP_ALIVE event */
static void ena_keep_alive_wd(void *adapter_data,
    struct ena_admin_aenq_entry *aenq_e)
{
        struct ena_adapter *adapter = (struct ena_adapter *)adapter_data;
        struct ena_admin_aenq_keep_alive_desc *desc;
        struct timeval time;
        uint64_t rx_drops;

        desc = (struct ena_admin_aenq_keep_alive_desc *)aenq_e;

        rx_drops = ((uint64_t)desc->rx_drops_high << 32) | desc->rx_drops_low;
        IFNET_STAT_INC(adapter->ifp, iqdrops, 1);
#if 0 /* XXX swildner counters */
        counter_u64_zero(adapter->hw_stats.rx_drops);
        counter_u64_add(adapter->hw_stats.rx_drops, rx_drops);
#endif

        getmicrouptime(&time);
        atomic_store_rel_64(&adapter->keep_alive_timestamp.tv_sec, time.tv_sec);
}

/* Check for keep alive expiration */
static void check_for_missing_keep_alive(struct ena_adapter *adapter)
{
        struct timeval timestamp, time;

        if (adapter->wd_active == 0)
                return;

        if (likely(adapter->keep_alive_timeout == 0))
                return;

        timestamp.tv_sec = atomic_load_acq_64(&adapter->keep_alive_timestamp.tv_sec);
        getmicrouptime(&time);
        timevalsub(&time, &timestamp);
        if (unlikely(time.tv_sec > adapter->keep_alive_timeout)) {
                device_printf(adapter->pdev,
                    "Keep alive watchdog timeout.\n");
#if 0 /* XXX swildner counters */
                counter_u64_add(adapter->dev_stats.wd_expired, 1);
#endif
                adapter->reset_reason = ENA_REGS_RESET_KEEP_ALIVE_TO;
                adapter->trigger_reset = true;
        }
}

/* Check if admin queue is enabled */
static void check_for_admin_com_state(struct ena_adapter *adapter)
{
        if (unlikely(ena_com_get_admin_running_state(adapter->ena_dev) ==
            false)) {
                device_printf(adapter->pdev,
                    "ENA admin queue is not in running state!\n");
#if 0 /* XXX swildner counters */
                counter_u64_add(adapter->dev_stats.admin_q_pause, 1);
#endif
                adapter->reset_reason = ENA_REGS_RESET_ADMIN_TO;
                adapter->trigger_reset = true;
        }
}

static int
check_missing_comp_in_queue(struct ena_adapter *adapter,
    struct ena_ring *tx_ring)
{
        struct timeval curtime, time;
        struct ena_tx_buffer *tx_buf;
        uint32_t missed_tx = 0;
        int i;

        getmicrouptime(&curtime);

        for (i = 0; i < tx_ring->ring_size; i++) {
                tx_buf = &tx_ring->tx_buffer_info[i];

                if (timevalisset(&tx_buf->timestamp) == 0)
                        continue;

                time = curtime;
                timevalsub(&time, &tx_buf->timestamp);

                /* Check again if packet is still waiting */
                //WATCH: Might not be exactly comparable
                if (unlikely(time.tv_sec > adapter->missing_tx_timeout)) {

                        if (!tx_buf->print_once)
                                ena_trace(ENA_WARNING, "Found a Tx that wasn't "
                                    "completed on time, qid %d, index %d.\n",
                                    tx_ring->qid, i);

                        tx_buf->print_once = true;
                        missed_tx++;
#if 0 /* XXX swildner counters */
                        counter_u64_add(tx_ring->tx_stats.missing_tx_comp, 1);
#endif

                        if (unlikely(missed_tx >
                            adapter->missing_tx_threshold)) {
                                device_printf(adapter->pdev,
                                    "The number of lost tx completion "
                                    "is above the threshold (%d > %d). "
                                    "Reset the device\n",
                                    missed_tx, adapter->missing_tx_threshold);
                                adapter->reset_reason =
                                    ENA_REGS_RESET_MISS_TX_CMPL;
                                adapter->trigger_reset = true;
                                return (EIO);
                        }
                }
        }

        return (0);
}

/*
 * Check for TX which were not completed on time.
 * Timeout is defined by "missing_tx_timeout".
 * Reset will be performed if number of incompleted
 * transactions exceeds "missing_tx_threshold".
 */
static void
check_for_missing_tx_completions(struct ena_adapter *adapter)
{
        struct ena_ring *tx_ring;
        int i, budget, rc;

        /* Make sure the driver doesn't turn the device in other process */
        rmb();

        if (!adapter->up)
                return;

        if (adapter->trigger_reset)
                return;

        if (adapter->missing_tx_timeout == 0)
                return;

        budget = adapter->missing_tx_max_queues;

        for (i = adapter->next_monitored_tx_qid; i < adapter->num_queues; i++) {
                tx_ring = &adapter->tx_ring[i];

                rc = check_missing_comp_in_queue(adapter, tx_ring);
                if (unlikely(rc != 0))
                        return;

                budget--;
                if (budget == 0) {
                        i++;
                        break;
                }
        }

        adapter->next_monitored_tx_qid = i % adapter->num_queues;
}

/* trigger deferred rx cleanup after 2 consecutive detections */
#define EMPTY_RX_REFILL 2
/* For the rare case where the device runs out of Rx descriptors and the
 * msix handler failed to refill new Rx descriptors (due to a lack of memory
 * for example).
 * This case will lead to a deadlock:
 * The device won't send interrupts since all the new Rx packets will be dropped
 * The msix handler won't allocate new Rx descriptors so the device won't be
 * able to send new packets.
 *
 * When such a situation is detected - execute rx cleanup task in another thread
 */
static void
check_for_empty_rx_ring(struct ena_adapter *adapter)
{
        struct ena_ring *rx_ring;
        int i, refill_required;

        if (!adapter->up)
                return;

        if (adapter->trigger_reset)
                return;

        for (i = 0; i < adapter->num_queues; i++) {
                rx_ring = &adapter->rx_ring[i];

                refill_required = ena_com_free_desc(rx_ring->ena_com_io_sq);
                if (unlikely(refill_required == (rx_ring->ring_size - 1))) {
                        rx_ring->empty_rx_queue++;

                        if (rx_ring->empty_rx_queue >= EMPTY_RX_REFILL) {
#if 0 /* XXX swildner counters */
                                counter_u64_add(rx_ring->rx_stats.empty_rx_ring,
                                    1);
#endif

                                device_printf(adapter->pdev,
                                    "trigger refill for ring %d\n", i);

                                taskqueue_enqueue(rx_ring->cmpl_tq,
                                    &rx_ring->cmpl_task);
                                rx_ring->empty_rx_queue = 0;
                        }
                } else {
                        rx_ring->empty_rx_queue = 0;
                }
        }
}

static void
ena_timer_service(void *data)
{
        struct ena_adapter *adapter = (struct ena_adapter *)data;
        struct ena_admin_host_info *host_info =
            adapter->ena_dev->host_attr.host_info;

        check_for_missing_keep_alive(adapter);

        check_for_admin_com_state(adapter);

        check_for_missing_tx_completions(adapter);

        check_for_empty_rx_ring(adapter);

        if (host_info != NULL)
                ena_update_host_info(host_info, adapter->ifp);

        if (unlikely(adapter->trigger_reset)) {
                device_printf(adapter->pdev, "Trigger reset is on\n");
                taskqueue_enqueue(adapter->reset_tq, &adapter->reset_task);
                return;
        }

        /*
         * Schedule another timeout one second from now.
         */
        /* XXX swildner callout_schedule_sbt(&adapter->timer_service, SBT_1S, SBT_1S, 0); */
        callout_reset(&adapter->timer_service, hz, ena_timer_service,
            (void *)adapter);
}

static void
ena_reset_task(void *arg, int pending)
{
        struct ena_com_dev_get_features_ctx get_feat_ctx;
        struct ena_adapter *adapter = (struct ena_adapter *)arg;
        struct ena_com_dev *ena_dev = adapter->ena_dev;
        bool dev_up;
        int rc;

        if (unlikely(!adapter->trigger_reset)) {
                device_printf(adapter->pdev,
                    "device reset scheduled but trigger_reset is off\n");
                return;
        }

        lockmgr(&adapter->ioctl_lock, LK_EXCLUSIVE);

        callout_drain(&adapter->timer_service);

        dev_up = adapter->up;

        ena_com_set_admin_running_state(ena_dev, false);
        ena_down(adapter);
        ena_free_mgmnt_irq(adapter);
        ena_disable_msix(adapter);
        ena_com_abort_admin_commands(ena_dev);
        ena_com_wait_for_abort_completion(ena_dev);
        ena_com_admin_destroy(ena_dev);
        ena_com_mmio_reg_read_request_destroy(ena_dev);

        adapter->reset_reason = ENA_REGS_RESET_NORMAL;
        adapter->trigger_reset = false;

        /* Finished destroy part. Restart the device */
        rc = ena_device_init(adapter, adapter->pdev, &get_feat_ctx,
            &adapter->wd_active);
        if (unlikely(rc != 0)) {
                device_printf(adapter->pdev,
                    "ENA device init failed! (err: %d)\n", rc);
                goto err_dev_free;
        }

        rc = ena_enable_msix_and_set_admin_interrupts(adapter,
            adapter->num_queues);
        if (unlikely(rc != 0)) {
                device_printf(adapter->pdev, "Enable MSI-X failed\n");
                goto err_com_free;
        }

        /* If the interface was up before the reset bring it up */
        if (dev_up) {
                rc = ena_up(adapter);
                if (unlikely(rc != 0)) {
                        device_printf(adapter->pdev,
                            "Failed to create I/O queues\n");
                        goto err_msix_free;
                }
        }

        callout_reset(&adapter->timer_service, hz,
            ena_timer_service, (void *)adapter);

        lockmgr(&adapter->ioctl_lock, LK_RELEASE);

        return;

err_msix_free:
        ena_free_mgmnt_irq(adapter);
        ena_disable_msix(adapter);
err_com_free:
        ena_com_admin_destroy(ena_dev);
err_dev_free:
        device_printf(adapter->pdev, "ENA reset failed!\n");
        adapter->running = false;
        lockmgr(&adapter->ioctl_lock, LK_RELEASE);
}

/**
 * ena_attach - Device Initialization Routine
 * @pdev: device information struct
 *
 * Returns 0 on success, otherwise on failure.
 *
 * ena_attach initializes an adapter identified by a device structure.
 * The OS initialization, configuring of the adapter private structure,
 * and a hardware reset occur.
 **/
static int
ena_attach(device_t pdev)
{
        struct ena_com_dev_get_features_ctx get_feat_ctx;
        static int version_printed;
        struct ena_adapter *adapter;
        struct ena_com_dev *ena_dev = NULL;
        uint16_t tx_sgl_size = 0;
        uint16_t rx_sgl_size = 0;
        int io_queue_num;
        int queue_size;
        int rc;
        adapter = device_get_softc(pdev);
        adapter->pdev = pdev;

        lockinit(&adapter->global_lock, "ENA global mtx", 0, LK_CANRECURSE);
        lockinit(&adapter->ioctl_lock, "ENA ioctl sx", 0, LK_CANRECURSE);

        /* Set up the timer service */
        callout_init_lk(&adapter->timer_service, &adapter->global_lock);
        adapter->keep_alive_timeout = DEFAULT_KEEP_ALIVE_TO;
        adapter->missing_tx_timeout = DEFAULT_TX_CMP_TO;
        adapter->missing_tx_max_queues = DEFAULT_TX_MONITORED_QUEUES;
        adapter->missing_tx_threshold = DEFAULT_TX_CMP_THRESHOLD;

        if (version_printed++ == 0)
                device_printf(pdev, "%s\n", ena_version);

        rc = ena_allocate_pci_resources(adapter);
        if (unlikely(rc != 0)) {
                device_printf(pdev, "PCI resource allocation failed!\n");
                ena_free_pci_resources(adapter);
                return (rc);
        }

        /* Allocate memory for ena_dev structure */
        ena_dev = kmalloc(sizeof(struct ena_com_dev), M_DEVBUF,
            M_WAITOK | M_ZERO);

        adapter->ena_dev = ena_dev;
        ena_dev->dmadev = pdev;
        ena_dev->bus = kmalloc(sizeof(struct ena_bus), M_DEVBUF,
            M_WAITOK | M_ZERO);

        /* Store register resources */
        ((struct ena_bus*)(ena_dev->bus))->reg_bar_t =
            rman_get_bustag(adapter->registers);
        ((struct ena_bus*)(ena_dev->bus))->reg_bar_h =
            rman_get_bushandle(adapter->registers);

        if (unlikely(((struct ena_bus*)(ena_dev->bus))->reg_bar_h == 0)) {
                device_printf(pdev, "failed to pmap registers bar\n");
                rc = ENXIO;
                goto err_bus_free;
        }

        ena_dev->tx_mem_queue_type = ENA_ADMIN_PLACEMENT_POLICY_HOST;

        /* Device initialization */
        rc = ena_device_init(adapter, pdev, &get_feat_ctx, &adapter->wd_active);
        if (unlikely(rc != 0)) {
                device_printf(pdev, "ENA device init failed! (err: %d)\n", rc);
                rc = ENXIO;
                goto err_bus_free;
        }

        getmicrouptime(&adapter->keep_alive_timestamp);

        adapter->tx_offload_cap = get_feat_ctx.offload.tx;

        /* Set for sure that interface is not up */
        adapter->up = false;

        memcpy(adapter->mac_addr, get_feat_ctx.dev_attr.mac_addr,
            ETHER_ADDR_LEN);

        /* calculate IO queue number to create */
        io_queue_num = ena_calc_io_queue_num(adapter, &get_feat_ctx);

        ENA_ASSERT(io_queue_num > 0, "Invalid queue number: %d\n",
            io_queue_num);
        adapter->num_queues = io_queue_num;

        adapter->max_mtu = get_feat_ctx.dev_attr.max_mtu;

        /* calculatre ring sizes */
        queue_size = ena_calc_queue_size(adapter,&tx_sgl_size,
            &rx_sgl_size, &get_feat_ctx);
        if (unlikely((queue_size <= 0) || (io_queue_num <= 0))) {
                rc = ENA_COM_FAULT;
                goto err_com_free;
        }

        adapter->reset_reason = ENA_REGS_RESET_NORMAL;

        adapter->tx_ring_size = queue_size;
        adapter->rx_ring_size = queue_size;

        adapter->max_tx_sgl_size = tx_sgl_size;
        adapter->max_rx_sgl_size = rx_sgl_size;

        /* set up dma tags for rx and tx buffers */
        rc = ena_setup_tx_dma_tag(adapter);
        if (unlikely(rc != 0)) {
                device_printf(pdev, "Failed to create TX DMA tag\n");
                goto err_com_free;
        }

        rc = ena_setup_rx_dma_tag(adapter);
        if (unlikely(rc != 0)) {
                device_printf(pdev, "Failed to create RX DMA tag\n");
                goto err_tx_tag_free;
        }

        /* initialize rings basic information */
        device_printf(pdev, "initialize %d io queues\n", io_queue_num);
        ena_init_io_rings(adapter);

        /* setup network interface */
        rc = ena_setup_ifnet(pdev, adapter, &get_feat_ctx);
        if (unlikely(rc != 0)) {
                device_printf(pdev, "Error with network interface setup\n");
                goto err_io_free;
        }

        rc = ena_enable_msix_and_set_admin_interrupts(adapter, io_queue_num);
        if (unlikely(rc != 0)) {
                device_printf(pdev,
                    "Failed to enable and set the admin interrupts\n");
                goto err_ifp_free;
        }

        /* Initialize reset task queue */
        TASK_INIT(&adapter->reset_task, 0, ena_reset_task, adapter);
        adapter->reset_tq = taskqueue_create("ena_reset_enqueue",
            M_WAITOK | M_ZERO, taskqueue_thread_enqueue, &adapter->reset_tq);
        taskqueue_start_threads(&adapter->reset_tq, 1, TDPRI_KERN_DAEMON, -1,
            "%s rstq", device_get_nameunit(adapter->pdev));

        /* Initialize statistics */
#if 0 /* XXX swildner counters */
        ena_alloc_counters((counter_u64_t *)&adapter->dev_stats,
            sizeof(struct ena_stats_dev));
        ena_alloc_counters((counter_u64_t *)&adapter->hw_stats,
            sizeof(struct ena_hw_stats));
#endif
        ena_sysctl_add_nodes(adapter);

        /* Tell the stack that the interface is not active */
        ifq_set_oactive(&adapter->ifp->if_snd);
        adapter->ifp->if_flags &= ~IFF_RUNNING;

        adapter->running = true;
        return (0);

err_ifp_free:
        if_detach(adapter->ifp);
        if_free(adapter->ifp);
err_io_free:
        ena_free_all_io_rings_resources(adapter);
        ena_free_rx_dma_tag(adapter);
err_tx_tag_free:
        ena_free_tx_dma_tag(adapter);
err_com_free:
        ena_com_admin_destroy(ena_dev);
        ena_com_delete_host_info(ena_dev);
        ena_com_mmio_reg_read_request_destroy(ena_dev);
err_bus_free:
        kfree(ena_dev->bus, M_DEVBUF);
        kfree(ena_dev, M_DEVBUF);
        ena_free_pci_resources(adapter);

        return (rc);
}

/**
 * ena_detach - Device Removal Routine
 * @pdev: device information struct
 *
 * ena_detach is called by the device subsystem to alert the driver
 * that it should release a PCI device.
 **/
static int
ena_detach(device_t pdev)
{
        struct ena_adapter *adapter = device_get_softc(pdev);
        struct ena_com_dev *ena_dev = adapter->ena_dev;
        int rc;

        /* Make sure VLANS are not using driver */
        if (adapter->ifp->if_vlantrunks != NULL) {
                device_printf(adapter->pdev ,"VLAN is in use, detach first\n");
                return (EBUSY);
        }

        /* Free reset task and callout */
        callout_drain(&adapter->timer_service);
        while (taskqueue_cancel(adapter->reset_tq, &adapter->reset_task, NULL))
                taskqueue_drain(adapter->reset_tq, &adapter->reset_task);
        taskqueue_free(adapter->reset_tq);

        lockmgr(&adapter->ioctl_lock, LK_EXCLUSIVE);
        ena_down(adapter);
        lockmgr(&adapter->ioctl_lock, LK_RELEASE);

        if (adapter->ifp != NULL) {
                ether_ifdetach(adapter->ifp);
                if_free(adapter->ifp);
        }

        ena_free_all_io_rings_resources(adapter);

#if 0 /* XXX swildner counters */
        ena_free_counters((counter_u64_t *)&adapter->hw_stats,
            sizeof(struct ena_hw_stats));
        ena_free_counters((counter_u64_t *)&adapter->dev_stats,
            sizeof(struct ena_stats_dev));
#endif

        if (likely(adapter->rss_support))
                ena_com_rss_destroy(ena_dev);

        rc = ena_free_rx_dma_tag(adapter);
        if (unlikely(rc != 0))
                device_printf(adapter->pdev,
                    "Unmapped RX DMA tag associations\n");

        rc = ena_free_tx_dma_tag(adapter);
        if (unlikely(rc != 0))
                device_printf(adapter->pdev,
                    "Unmapped TX DMA tag associations\n");

        /* Reset the device only if the device is running. */
        if (adapter->running)
                ena_com_dev_reset(ena_dev, adapter->reset_reason);

        ena_com_delete_host_info(ena_dev);

        ena_free_irqs(adapter);

        ena_com_abort_admin_commands(ena_dev);

        ena_com_wait_for_abort_completion(ena_dev);

        ena_com_admin_destroy(ena_dev);

        ena_com_mmio_reg_read_request_destroy(ena_dev);

        ena_free_pci_resources(adapter);

        lockuninit(&adapter->global_lock);
        lockuninit(&adapter->ioctl_lock);

        if (ena_dev->bus != NULL)
                kfree(ena_dev->bus, M_DEVBUF);

        if (ena_dev != NULL)
                kfree(ena_dev, M_DEVBUF);

        return (bus_generic_detach(pdev));
}

/******************************************************************************
 ******************************** AENQ Handlers *******************************
 *****************************************************************************/
/**
 * ena_update_on_link_change:
 * Notify the network interface about the change in link status
 **/
static void
ena_update_on_link_change(void *adapter_data,
    struct ena_admin_aenq_entry *aenq_e)
{
        struct ena_adapter *adapter = (struct ena_adapter *)adapter_data;
        struct ena_admin_aenq_link_change_desc *aenq_desc;
        int status;
        if_t ifp;

        aenq_desc = (struct ena_admin_aenq_link_change_desc *)aenq_e;
        ifp = adapter->ifp;
        status = aenq_desc->flags &
            ENA_ADMIN_AENQ_LINK_CHANGE_DESC_LINK_STATUS_MASK;

        if (status != 0) {
                device_printf(adapter->pdev, "link is UP\n");
                ifp->if_link_state = LINK_STATE_UP;
                if_link_state_change(ifp);
        } else if (status == 0) {
                device_printf(adapter->pdev, "link is DOWN\n");
                ifp->if_link_state = LINK_STATE_DOWN;
                if_link_state_change(ifp);
        } else {
                device_printf(adapter->pdev, "invalid value recvd\n");
                BUG();
        }

        adapter->link_status = status;
}

/**
 * This handler will called for unknown event group or unimplemented handlers
 **/
static void
unimplemented_aenq_handler(void *data,
    struct ena_admin_aenq_entry *aenq_e)
{
        return;
}

static struct ena_aenq_handlers aenq_handlers = {
    .handlers = {
            [ENA_ADMIN_LINK_CHANGE] = ena_update_on_link_change,
            [ENA_ADMIN_KEEP_ALIVE] = ena_keep_alive_wd,
    },
    .unimplemented_handler = unimplemented_aenq_handler
};

/*********************************************************************
 *  FreeBSD Device Interface Entry Points
 *********************************************************************/

static device_method_t ena_methods[] = {
    /* Device interface */
    DEVMETHOD(device_probe, ena_probe),
    DEVMETHOD(device_attach, ena_attach),
    DEVMETHOD(device_detach, ena_detach),
    DEVMETHOD_END
};

static driver_t ena_driver = {
    "ena", ena_methods, sizeof(struct ena_adapter),
};

devclass_t ena_devclass;
DRIVER_MODULE(ena, pci, ena_driver, ena_devclass, NULL, NULL);
MODULE_DEPEND(ena, pci, 1, 1, 1);
MODULE_DEPEND(ena, ether, 1, 1, 1);

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