root/sys/dev/cxgbe/t4_sge.c
/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2011, 2025 Chelsio Communications.
 * Written by: Navdeep Parhar <np@FreeBSD.org>
 *
 * 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 AUTHOR 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 AUTHOR 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.
 */

#include <sys/cdefs.h>
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_kern_tls.h"
#include "opt_ratelimit.h"

#include <sys/types.h>
#include <sys/eventhandler.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/kernel.h>
#include <sys/ktls.h>
#include <sys/malloc.h>
#include <sys/msan.h>
#include <sys/queue.h>
#include <sys/sbuf.h>
#include <sys/taskqueue.h>
#include <sys/time.h>
#include <sys/sglist.h>
#include <sys/sysctl.h>
#include <sys/smp.h>
#include <sys/socketvar.h>
#include <sys/counter.h>
#include <net/bpf.h>
#include <net/ethernet.h>
#include <net/if.h>
#include <net/if_vlan_var.h>
#include <net/if_vxlan.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/ip6.h>
#include <netinet/tcp.h>
#include <netinet/udp.h>
#include <machine/in_cksum.h>
#include <machine/md_var.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#ifdef DEV_NETMAP
#include <machine/bus.h>
#include <sys/selinfo.h>
#include <net/if_var.h>
#include <net/netmap.h>
#include <dev/netmap/netmap_kern.h>
#endif

#include "common/common.h"
#include "common/t4_regs.h"
#include "common/t4_regs_values.h"
#include "common/t4_msg.h"
#include "t4_l2t.h"
#include "t4_mp_ring.h"

#define RX_COPY_THRESHOLD MINCLSIZE

/*
 * Ethernet frames are DMA'd at this byte offset into the freelist buffer.
 * 0-7 are valid values.
 */
static int fl_pktshift = 0;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, fl_pktshift, CTLFLAG_RDTUN, &fl_pktshift, 0,
    "payload DMA offset in rx buffer (bytes)");

/*
 * Pad ethernet payload up to this boundary.
 * -1: driver should figure out a good value.
 *  0: disable padding.
 *  Any power of 2 from 32 to 4096 (both inclusive) is also a valid value.
 */
int fl_pad = -1;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, fl_pad, CTLFLAG_RDTUN, &fl_pad, 0,
    "payload pad boundary (bytes)");

/*
 * Status page length.
 * -1: driver should figure out a good value.
 *  64 or 128 are the only other valid values.
 */
static int spg_len = -1;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, spg_len, CTLFLAG_RDTUN, &spg_len, 0,
    "status page size (bytes)");

/*
 * Congestion drops.
 * -1: no congestion feedback (not recommended).
 *  0: backpressure the channel instead of dropping packets right away.
 *  1: no backpressure, drop packets for the congested queue immediately.
 *  2: both backpressure and drop.
 */
static int cong_drop = 0;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, cong_drop, CTLFLAG_RDTUN, &cong_drop, 0,
    "Congestion control for NIC RX queues (0 = backpressure, 1 = drop, 2 = both");
#ifdef TCP_OFFLOAD
static int ofld_cong_drop = 0;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, ofld_cong_drop, CTLFLAG_RDTUN, &ofld_cong_drop, 0,
    "Congestion control for TOE RX queues (0 = backpressure, 1 = drop, 2 = both");
#endif

/*
 * Deliver multiple frames in the same free list buffer if they fit.
 * -1: let the driver decide whether to enable buffer packing or not.
 *  0: disable buffer packing.
 *  1: enable buffer packing.
 */
static int buffer_packing = -1;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, buffer_packing, CTLFLAG_RDTUN, &buffer_packing,
    0, "Enable buffer packing");

/*
 * Start next frame in a packed buffer at this boundary.
 * -1: driver should figure out a good value.
 * T4: driver will ignore this and use the same value as fl_pad above.
 * T5: 16, or a power of 2 from 64 to 4096 (both inclusive) is a valid value.
 */
static int fl_pack = -1;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, fl_pack, CTLFLAG_RDTUN, &fl_pack, 0,
    "payload pack boundary (bytes)");

/*
 * Largest rx cluster size that the driver is allowed to allocate.
 */
static int largest_rx_cluster = MJUM16BYTES;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, largest_rx_cluster, CTLFLAG_RDTUN,
    &largest_rx_cluster, 0, "Largest rx cluster (bytes)");

/*
 * Size of cluster allocation that's most likely to succeed.  The driver will
 * fall back to this size if it fails to allocate clusters larger than this.
 */
static int safest_rx_cluster = PAGE_SIZE;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, safest_rx_cluster, CTLFLAG_RDTUN,
    &safest_rx_cluster, 0, "Safe rx cluster (bytes)");

#ifdef RATELIMIT
/*
 * Knob to control TCP timestamp rewriting, and the granularity of the tick used
 * for rewriting.  -1 and 0-3 are all valid values.
 * -1: hardware should leave the TCP timestamps alone.
 * 0: 1ms
 * 1: 100us
 * 2: 10us
 * 3: 1us
 */
static int tsclk = -1;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, tsclk, CTLFLAG_RDTUN, &tsclk, 0,
    "Control TCP timestamp rewriting when using pacing");

static int eo_max_backlog = 1024 * 1024;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, eo_max_backlog, CTLFLAG_RDTUN, &eo_max_backlog,
    0, "Maximum backlog of ratelimited data per flow");
#endif

/*
 * The interrupt holdoff timers are multiplied by this value on T6+.
 * 1 and 3-17 (both inclusive) are legal values.
 */
static int tscale = 1;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, tscale, CTLFLAG_RDTUN, &tscale, 0,
    "Interrupt holdoff timer scale on T6+");

/*
 * Number of LRO entries in the lro_ctrl structure per rx queue.
 */
static int lro_entries = TCP_LRO_ENTRIES;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, lro_entries, CTLFLAG_RDTUN, &lro_entries, 0,
    "Number of LRO entries per RX queue");

/*
 * This enables presorting of frames before they're fed into tcp_lro_rx.
 */
static int lro_mbufs = 0;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, lro_mbufs, CTLFLAG_RDTUN, &lro_mbufs, 0,
    "Enable presorting of LRO frames");

static counter_u64_t pullups;
SYSCTL_COUNTER_U64(_hw_cxgbe, OID_AUTO, pullups, CTLFLAG_RD, &pullups,
    "Number of mbuf pullups performed");

static counter_u64_t defrags;
SYSCTL_COUNTER_U64(_hw_cxgbe, OID_AUTO, defrags, CTLFLAG_RD, &defrags,
    "Number of mbuf defrags performed");

static int t4_tx_coalesce = 1;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, tx_coalesce, CTLFLAG_RWTUN, &t4_tx_coalesce, 0,
    "tx coalescing allowed");

/*
 * The driver will make aggressive attempts at tx coalescing if it sees these
 * many packets eligible for coalescing in quick succession, with no more than
 * the specified gap in between the eth_tx calls that delivered the packets.
 */
static int t4_tx_coalesce_pkts = 32;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, tx_coalesce_pkts, CTLFLAG_RWTUN,
    &t4_tx_coalesce_pkts, 0,
    "# of consecutive packets (1 - 255) that will trigger tx coalescing");
static int t4_tx_coalesce_gap = 5;
SYSCTL_INT(_hw_cxgbe, OID_AUTO, tx_coalesce_gap, CTLFLAG_RWTUN,
    &t4_tx_coalesce_gap, 0, "tx gap (in microseconds)");

static int service_iq(struct sge_iq *, int);
static int service_iq_fl(struct sge_iq *, int);
static struct mbuf *get_fl_payload(struct adapter *, struct sge_fl *, uint32_t);
static int eth_rx(struct adapter *, struct sge_rxq *, const struct iq_desc *,
    u_int);
static inline void init_iq(struct sge_iq *, struct adapter *, int, int, int,
    int, int, int);
static inline void init_fl(struct adapter *, struct sge_fl *, int, int, char *);
static inline void init_eq(struct adapter *, struct sge_eq *, int, int, uint8_t,
    struct sge_iq *, char *);
static int alloc_iq_fl(struct vi_info *, struct sge_iq *, struct sge_fl *,
    struct sysctl_ctx_list *, struct sysctl_oid *);
static void free_iq_fl(struct adapter *, struct sge_iq *, struct sge_fl *);
static void add_iq_sysctls(struct sysctl_ctx_list *, struct sysctl_oid *,
    struct sge_iq *);
static void add_fl_sysctls(struct adapter *, struct sysctl_ctx_list *,
    struct sysctl_oid *, struct sge_fl *);
static int alloc_iq_fl_hwq(struct vi_info *, struct sge_iq *, struct sge_fl *);
static int free_iq_fl_hwq(struct adapter *, struct sge_iq *, struct sge_fl *);
static int alloc_fwq(struct adapter *);
static void free_fwq(struct adapter *);
static int alloc_ctrlq(struct adapter *, int);
static void free_ctrlq(struct adapter *, int);
static int alloc_rxq(struct vi_info *, struct sge_rxq *, int, int, int);
static void free_rxq(struct vi_info *, struct sge_rxq *);
static void add_rxq_sysctls(struct sysctl_ctx_list *, struct sysctl_oid *,
    struct sge_rxq *);
#ifdef TCP_OFFLOAD
static int alloc_ofld_rxq(struct vi_info *, struct sge_ofld_rxq *, int, int,
    int);
static void free_ofld_rxq(struct vi_info *, struct sge_ofld_rxq *);
static void add_ofld_rxq_sysctls(struct sysctl_ctx_list *, struct sysctl_oid *,
    struct sge_ofld_rxq *);
#endif
static int ctrl_eq_alloc(struct adapter *, struct sge_eq *, int);
static int eth_eq_alloc(struct adapter *, struct vi_info *, struct sge_eq *,
    int);
#if defined(TCP_OFFLOAD) || defined(RATELIMIT)
static int ofld_eq_alloc(struct adapter *, struct vi_info *, struct sge_eq *,
    int);
#endif
static int alloc_eq(struct adapter *, struct sge_eq *, struct sysctl_ctx_list *,
    struct sysctl_oid *);
static void free_eq(struct adapter *, struct sge_eq *);
static void add_eq_sysctls(struct adapter *, struct sysctl_ctx_list *,
    struct sysctl_oid *, struct sge_eq *);
static int alloc_eq_hwq(struct adapter *, struct vi_info *, struct sge_eq *,
    int);
static int free_eq_hwq(struct adapter *, struct vi_info *, struct sge_eq *);
static int alloc_wrq(struct adapter *, struct vi_info *, struct sge_wrq *,
    struct sysctl_ctx_list *, struct sysctl_oid *);
static void free_wrq(struct adapter *, struct sge_wrq *);
static void add_wrq_sysctls(struct sysctl_ctx_list *, struct sysctl_oid *,
    struct sge_wrq *);
static int alloc_txq(struct vi_info *, struct sge_txq *, int);
static void free_txq(struct vi_info *, struct sge_txq *);
static void add_txq_sysctls(struct vi_info *, struct sysctl_ctx_list *,
    struct sysctl_oid *, struct sge_txq *);
#if defined(TCP_OFFLOAD) || defined(RATELIMIT)
static int alloc_ofld_txq(struct vi_info *, struct sge_ofld_txq *, int);
static void free_ofld_txq(struct vi_info *, struct sge_ofld_txq *);
static void add_ofld_txq_sysctls(struct sysctl_ctx_list *, struct sysctl_oid *,
    struct sge_ofld_txq *);
#endif
static void oneseg_dma_callback(void *, bus_dma_segment_t *, int, int);
static inline void ring_fl_db(struct adapter *, struct sge_fl *);
static int refill_fl(struct adapter *, struct sge_fl *, int);
static void refill_sfl(void *);
static int find_refill_source(struct adapter *, int, bool);
static void add_fl_to_sfl(struct adapter *, struct sge_fl *);

static inline void get_pkt_gl(struct mbuf *, struct sglist *);
static inline u_int txpkt_len16(u_int, const u_int);
static inline u_int txpkt_vm_len16(u_int, const u_int);
static inline void calculate_mbuf_len16(struct mbuf *, bool);
static inline u_int txpkts0_len16(u_int);
static inline u_int txpkts1_len16(void);
static u_int write_raw_wr(struct sge_txq *, void *, struct mbuf *, u_int);
static u_int write_txpkt_wr(struct adapter *, struct sge_txq *, struct mbuf *,
    u_int);
static u_int write_txpkt_vm_wr(struct adapter *, struct sge_txq *,
    struct mbuf *);
static int add_to_txpkts_vf(struct adapter *, struct sge_txq *, struct mbuf *,
    int, bool *);
static int add_to_txpkts_pf(struct adapter *, struct sge_txq *, struct mbuf *,
    int, bool *);
static u_int write_txpkts_wr(struct adapter *, struct sge_txq *);
static u_int write_txpkts_vm_wr(struct adapter *, struct sge_txq *);
static void write_gl_to_txd(struct sge_txq *, struct mbuf *, caddr_t *, int);
static inline void copy_to_txd(struct sge_eq *, caddr_t, caddr_t *, int);
static inline void ring_eq_db(struct adapter *, struct sge_eq *, u_int);
static inline uint16_t read_hw_cidx(struct sge_eq *);
static inline u_int reclaimable_tx_desc(struct sge_eq *);
static inline u_int total_available_tx_desc(struct sge_eq *);
static u_int reclaim_tx_descs(struct sge_txq *, u_int);
static void tx_reclaim(void *, int);
static __be64 get_flit(struct sglist_seg *, int, int);
static int handle_sge_egr_update(struct sge_iq *, const struct rss_header *,
    struct mbuf *);
static int handle_fw_msg(struct sge_iq *, const struct rss_header *,
    struct mbuf *);
static int t4_handle_wrerr_rpl(struct adapter *, const __be64 *);
static void wrq_tx_drain(void *, int);
static void drain_wrq_wr_list(struct adapter *, struct sge_wrq *);

static int sysctl_bufsizes(SYSCTL_HANDLER_ARGS);
#ifdef RATELIMIT
static int ethofld_fw4_ack(struct sge_iq *, const struct rss_header *,
    struct mbuf *);
#if defined(INET) || defined(INET6)
static inline u_int txpkt_eo_len16(u_int, u_int, u_int);
static int ethofld_transmit(if_t, struct mbuf *);
#endif
#endif

static counter_u64_t extfree_refs;
static counter_u64_t extfree_rels;

an_handler_t t4_an_handler;
fw_msg_handler_t t4_fw_msg_handler[NUM_FW6_TYPES];
cpl_handler_t t4_cpl_handler[NUM_CPL_CMDS];
cpl_handler_t set_tcb_rpl_handlers[NUM_CPL_COOKIES];
cpl_handler_t l2t_write_rpl_handlers[NUM_CPL_COOKIES];
cpl_handler_t act_open_rpl_handlers[NUM_CPL_COOKIES];
cpl_handler_t abort_rpl_rss_handlers[NUM_CPL_COOKIES];
cpl_handler_t fw4_ack_handlers[NUM_CPL_COOKIES];
cpl_handler_t fw6_pld_handlers[NUM_CPL_FW6_COOKIES];

void
t4_register_an_handler(an_handler_t h)
{
        uintptr_t *loc;

        MPASS(h == NULL || t4_an_handler == NULL);

        loc = (uintptr_t *)&t4_an_handler;
        atomic_store_rel_ptr(loc, (uintptr_t)h);
}

void
t4_register_fw_msg_handler(int type, fw_msg_handler_t h)
{
        uintptr_t *loc;

        MPASS(type < nitems(t4_fw_msg_handler));
        MPASS(h == NULL || t4_fw_msg_handler[type] == NULL);
        /*
         * These are dispatched by the handler for FW{4|6}_CPL_MSG using the CPL
         * handler dispatch table.  Reject any attempt to install a handler for
         * this subtype.
         */
        MPASS(type != FW_TYPE_RSSCPL);
        MPASS(type != FW6_TYPE_RSSCPL);

        loc = (uintptr_t *)&t4_fw_msg_handler[type];
        atomic_store_rel_ptr(loc, (uintptr_t)h);
}

void
t4_register_cpl_handler(int opcode, cpl_handler_t h)
{
        uintptr_t *loc;

        MPASS(opcode < nitems(t4_cpl_handler));
        MPASS(h == NULL || t4_cpl_handler[opcode] == NULL);

        loc = (uintptr_t *)&t4_cpl_handler[opcode];
        atomic_store_rel_ptr(loc, (uintptr_t)h);
}

static int
set_tcb_rpl_handler(struct sge_iq *iq, const struct rss_header *rss,
    struct mbuf *m)
{
        const struct cpl_set_tcb_rpl *cpl = (const void *)(rss + 1);
        u_int tid;
        int cookie;

        MPASS(m == NULL);

        tid = GET_TID(cpl);
        if (is_hpftid(iq->adapter, tid) || is_ftid(iq->adapter, tid)) {
                /*
                 * The return code for filter-write is put in the CPL cookie so
                 * we have to rely on the hardware tid (is_ftid) to determine
                 * that this is a response to a filter.
                 */
                cookie = CPL_COOKIE_FILTER;
        } else {
                cookie = G_COOKIE(cpl->cookie);
        }
        MPASS(cookie > CPL_COOKIE_RESERVED);
        MPASS(cookie < nitems(set_tcb_rpl_handlers));

        return (set_tcb_rpl_handlers[cookie](iq, rss, m));
}

static int
l2t_write_rpl_handler(struct sge_iq *iq, const struct rss_header *rss,
    struct mbuf *m)
{
        const struct cpl_l2t_write_rpl *rpl = (const void *)(rss + 1);
        unsigned int cookie;

        MPASS(m == NULL);

        cookie = GET_TID(rpl) & F_SYNC_WR ? CPL_COOKIE_TOM : CPL_COOKIE_FILTER;
        return (l2t_write_rpl_handlers[cookie](iq, rss, m));
}

static int
act_open_rpl_handler(struct sge_iq *iq, const struct rss_header *rss,
    struct mbuf *m)
{
        const struct cpl_act_open_rpl *cpl = (const void *)(rss + 1);
        u_int cookie = G_TID_COOKIE(G_AOPEN_ATID(be32toh(cpl->atid_status)));

        MPASS(m == NULL);
        MPASS(cookie != CPL_COOKIE_RESERVED);

        return (act_open_rpl_handlers[cookie](iq, rss, m));
}

static int
abort_rpl_rss_handler(struct sge_iq *iq, const struct rss_header *rss,
    struct mbuf *m)
{
        struct adapter *sc = iq->adapter;
        u_int cookie;

        MPASS(m == NULL);
        if (is_hashfilter(sc))
                cookie = CPL_COOKIE_HASHFILTER;
        else
                cookie = CPL_COOKIE_TOM;

        return (abort_rpl_rss_handlers[cookie](iq, rss, m));
}

static int
fw4_ack_handler(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
{
        struct adapter *sc = iq->adapter;
        const struct cpl_fw4_ack *cpl = (const void *)(rss + 1);
        unsigned int tid = G_CPL_FW4_ACK_FLOWID(be32toh(OPCODE_TID(cpl)));
        u_int cookie;

        MPASS(m == NULL);
        if (is_etid(sc, tid))
                cookie = CPL_COOKIE_ETHOFLD;
        else
                cookie = CPL_COOKIE_TOM;

        return (fw4_ack_handlers[cookie](iq, rss, m));
}

static int
fw6_pld_handler(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
{
        const struct cpl_fw6_pld *cpl;
        uint64_t cookie;

        if (m != NULL)
                cpl = mtod(m, const void *);
        else
                cpl = (const void *)(rss + 1);
        cookie = be64toh(cpl->data[1]) & CPL_FW6_COOKIE_MASK;

        return (fw6_pld_handlers[cookie](iq, rss, m));
}

static void
t4_init_shared_cpl_handlers(void)
{

        t4_register_cpl_handler(CPL_SET_TCB_RPL, set_tcb_rpl_handler);
        t4_register_cpl_handler(CPL_L2T_WRITE_RPL, l2t_write_rpl_handler);
        t4_register_cpl_handler(CPL_ACT_OPEN_RPL, act_open_rpl_handler);
        t4_register_cpl_handler(CPL_ABORT_RPL_RSS, abort_rpl_rss_handler);
        t4_register_cpl_handler(CPL_FW4_ACK, fw4_ack_handler);
        t4_register_cpl_handler(CPL_FW6_PLD, fw6_pld_handler);
}

void
t4_register_shared_cpl_handler(int opcode, cpl_handler_t h, int cookie)
{
        uintptr_t *loc;

        MPASS(opcode < nitems(t4_cpl_handler));
        if (opcode == CPL_FW6_PLD) {
                MPASS(cookie < NUM_CPL_FW6_COOKIES);
        } else {
                MPASS(cookie > CPL_COOKIE_RESERVED);
                MPASS(cookie < NUM_CPL_COOKIES);
        }
        MPASS(t4_cpl_handler[opcode] != NULL);

        switch (opcode) {
        case CPL_SET_TCB_RPL:
                loc = (uintptr_t *)&set_tcb_rpl_handlers[cookie];
                break;
        case CPL_L2T_WRITE_RPL:
                loc = (uintptr_t *)&l2t_write_rpl_handlers[cookie];
                break;
        case CPL_ACT_OPEN_RPL:
                loc = (uintptr_t *)&act_open_rpl_handlers[cookie];
                break;
        case CPL_ABORT_RPL_RSS:
                loc = (uintptr_t *)&abort_rpl_rss_handlers[cookie];
                break;
        case CPL_FW4_ACK:
                loc = (uintptr_t *)&fw4_ack_handlers[cookie];
                break;
        case CPL_FW6_PLD:
                loc = (uintptr_t *)&fw6_pld_handlers[cookie];
                break;
        default:
                MPASS(0);
                return;
        }
        MPASS(h == NULL || *loc == (uintptr_t)NULL);
        atomic_store_rel_ptr(loc, (uintptr_t)h);
}

/*
 * Called on MOD_LOAD.  Validates and calculates the SGE tunables.
 */
void
t4_sge_modload(void)
{

        if (fl_pktshift < 0 || fl_pktshift > 7) {
                printf("Invalid hw.cxgbe.fl_pktshift value (%d),"
                    " using 0 instead.\n", fl_pktshift);
                fl_pktshift = 0;
        }

        if (spg_len != 64 && spg_len != 128) {
                int len;

#if defined(__i386__) || defined(__amd64__)
                len = cpu_clflush_line_size > 64 ? 128 : 64;
#else
                len = 64;
#endif
                if (spg_len != -1) {
                        printf("Invalid hw.cxgbe.spg_len value (%d),"
                            " using %d instead.\n", spg_len, len);
                }
                spg_len = len;
        }

        if (cong_drop < -1 || cong_drop > 2) {
                printf("Invalid hw.cxgbe.cong_drop value (%d),"
                    " using 0 instead.\n", cong_drop);
                cong_drop = 0;
        }
#ifdef TCP_OFFLOAD
        if (ofld_cong_drop < -1 || ofld_cong_drop > 2) {
                printf("Invalid hw.cxgbe.ofld_cong_drop value (%d),"
                    " using 0 instead.\n", ofld_cong_drop);
                ofld_cong_drop = 0;
        }
#endif

        if (tscale != 1 && (tscale < 3 || tscale > 17)) {
                printf("Invalid hw.cxgbe.tscale value (%d),"
                    " using 1 instead.\n", tscale);
                tscale = 1;
        }

        if (largest_rx_cluster != MCLBYTES &&
#if MJUMPAGESIZE != MCLBYTES
            largest_rx_cluster != MJUMPAGESIZE &&
#endif
            largest_rx_cluster != MJUM9BYTES &&
            largest_rx_cluster != MJUM16BYTES) {
                printf("Invalid hw.cxgbe.largest_rx_cluster value (%d),"
                    " using %d instead.\n", largest_rx_cluster, MJUM16BYTES);
                largest_rx_cluster = MJUM16BYTES;
        }

        if (safest_rx_cluster != MCLBYTES &&
#if MJUMPAGESIZE != MCLBYTES
            safest_rx_cluster != MJUMPAGESIZE &&
#endif
            safest_rx_cluster != MJUM9BYTES &&
            safest_rx_cluster != MJUM16BYTES) {
                printf("Invalid hw.cxgbe.safest_rx_cluster value (%d),"
                    " using %d instead.\n", safest_rx_cluster, MJUMPAGESIZE);
                safest_rx_cluster = MJUMPAGESIZE;
        }

        extfree_refs = counter_u64_alloc(M_WAITOK);
        extfree_rels = counter_u64_alloc(M_WAITOK);
        pullups = counter_u64_alloc(M_WAITOK);
        defrags = counter_u64_alloc(M_WAITOK);
        counter_u64_zero(extfree_refs);
        counter_u64_zero(extfree_rels);
        counter_u64_zero(pullups);
        counter_u64_zero(defrags);

        t4_init_shared_cpl_handlers();
        t4_register_cpl_handler(CPL_FW4_MSG, handle_fw_msg);
        t4_register_cpl_handler(CPL_FW6_MSG, handle_fw_msg);
        t4_register_cpl_handler(CPL_SGE_EGR_UPDATE, handle_sge_egr_update);
#ifdef RATELIMIT
        t4_register_shared_cpl_handler(CPL_FW4_ACK, ethofld_fw4_ack,
            CPL_COOKIE_ETHOFLD);
#endif
        t4_register_fw_msg_handler(FW6_TYPE_CMD_RPL, t4_handle_fw_rpl);
        t4_register_fw_msg_handler(FW6_TYPE_WRERR_RPL, t4_handle_wrerr_rpl);
}

void
t4_sge_modunload(void)
{

        counter_u64_free(extfree_refs);
        counter_u64_free(extfree_rels);
        counter_u64_free(pullups);
        counter_u64_free(defrags);
}

uint64_t
t4_sge_extfree_refs(void)
{
        uint64_t refs, rels;

        rels = counter_u64_fetch(extfree_rels);
        refs = counter_u64_fetch(extfree_refs);

        return (refs - rels);
}

/* max 4096 */
#define MAX_PACK_BOUNDARY 512

static inline void
setup_pad_and_pack_boundaries(struct adapter *sc)
{
        uint32_t v, m;
        int pad, pack, pad_shift;

        pad_shift = chip_id(sc) > CHELSIO_T5 ? X_T6_INGPADBOUNDARY_SHIFT :
            X_INGPADBOUNDARY_SHIFT;
        pad = fl_pad;
        if (fl_pad < (1 << pad_shift) ||
            fl_pad > (1 << (pad_shift + M_INGPADBOUNDARY)) ||
            !powerof2(fl_pad)) {
                /*
                 * If there is any chance that we might use buffer packing and
                 * the chip is a T4, then pick 64 as the pad/pack boundary.  Set
                 * it to the minimum allowed in all other cases.
                 */
                pad = is_t4(sc) && buffer_packing ? 64 : 1 << pad_shift;

                /*
                 * For fl_pad = 0 we'll still write a reasonable value to the
                 * register but all the freelists will opt out of padding.
                 * We'll complain here only if the user tried to set it to a
                 * value greater than 0 that was invalid.
                 */
                if (fl_pad > 0) {
                        device_printf(sc->dev, "Invalid hw.cxgbe.fl_pad value"
                            " (%d), using %d instead.\n", fl_pad, pad);
                }
        }
        m = V_INGPADBOUNDARY(M_INGPADBOUNDARY);
        v = V_INGPADBOUNDARY(ilog2(pad) - pad_shift);
        t4_set_reg_field(sc, A_SGE_CONTROL, m, v);

        if (is_t4(sc)) {
                if (fl_pack != -1 && fl_pack != pad) {
                        /* Complain but carry on. */
                        device_printf(sc->dev, "hw.cxgbe.fl_pack (%d) ignored,"
                            " using %d instead.\n", fl_pack, pad);
                }
                return;
        }

        pack = fl_pack;
        if (fl_pack < 16 || fl_pack == 32 || fl_pack > 4096 ||
            !powerof2(fl_pack)) {
                if (sc->params.pci.mps > MAX_PACK_BOUNDARY)
                        pack = MAX_PACK_BOUNDARY;
                else
                        pack = max(sc->params.pci.mps, CACHE_LINE_SIZE);
                MPASS(powerof2(pack));
                if (pack < 16)
                        pack = 16;
                if (pack == 32)
                        pack = 64;
                if (pack > 4096)
                        pack = 4096;
                if (fl_pack != -1) {
                        device_printf(sc->dev, "Invalid hw.cxgbe.fl_pack value"
                            " (%d), using %d instead.\n", fl_pack, pack);
                }
        }
        m = V_INGPACKBOUNDARY(M_INGPACKBOUNDARY);
        if (pack == 16)
                v = V_INGPACKBOUNDARY(0);
        else
                v = V_INGPACKBOUNDARY(ilog2(pack) - 5);

        MPASS(!is_t4(sc));      /* T4 doesn't have SGE_CONTROL2 */
        t4_set_reg_field(sc, A_SGE_CONTROL2, m, v);
}

/*
 * adap->params.vpd.cclk must be set up before this is called.
 */
void
t4_tweak_chip_settings(struct adapter *sc)
{
        int i, reg;
        uint32_t v, m;
        int intr_timer[SGE_NTIMERS] = {1, 5, 10, 50, 100, 200};
        int timer_max = M_TIMERVALUE0 * 1000 / sc->params.vpd.cclk;
        int intr_pktcount[SGE_NCOUNTERS] = {1, 8, 16, 32}; /* 63 max */
        uint16_t indsz = min(RX_COPY_THRESHOLD - 1, M_INDICATESIZE);
        static int sw_buf_sizes[] = {
                MCLBYTES,
#if MJUMPAGESIZE != MCLBYTES
                MJUMPAGESIZE,
#endif
                MJUM9BYTES,
                MJUM16BYTES
        };

        KASSERT(sc->flags & MASTER_PF,
            ("%s: trying to change chip settings when not master.", __func__));

        m = V_PKTSHIFT(M_PKTSHIFT) | F_RXPKTCPLMODE | F_EGRSTATUSPAGESIZE;
        v = V_PKTSHIFT(fl_pktshift) | F_RXPKTCPLMODE |
            V_EGRSTATUSPAGESIZE(spg_len == 128);
        t4_set_reg_field(sc, A_SGE_CONTROL, m, v);

        setup_pad_and_pack_boundaries(sc);

        v = V_HOSTPAGESIZEPF0(PAGE_SHIFT - 10) |
            V_HOSTPAGESIZEPF1(PAGE_SHIFT - 10) |
            V_HOSTPAGESIZEPF2(PAGE_SHIFT - 10) |
            V_HOSTPAGESIZEPF3(PAGE_SHIFT - 10) |
            V_HOSTPAGESIZEPF4(PAGE_SHIFT - 10) |
            V_HOSTPAGESIZEPF5(PAGE_SHIFT - 10) |
            V_HOSTPAGESIZEPF6(PAGE_SHIFT - 10) |
            V_HOSTPAGESIZEPF7(PAGE_SHIFT - 10);
        t4_write_reg(sc, A_SGE_HOST_PAGE_SIZE, v);

        t4_write_reg(sc, A_SGE_FL_BUFFER_SIZE0, 4096);
        t4_write_reg(sc, A_SGE_FL_BUFFER_SIZE1, 65536);
        reg = A_SGE_FL_BUFFER_SIZE2;
        for (i = 0; i < nitems(sw_buf_sizes); i++) {
                MPASS(reg <= A_SGE_FL_BUFFER_SIZE15);
                t4_write_reg(sc, reg, sw_buf_sizes[i]);
                reg += 4;
                MPASS(reg <= A_SGE_FL_BUFFER_SIZE15);
                t4_write_reg(sc, reg, sw_buf_sizes[i] - CL_METADATA_SIZE);
                reg += 4;
        }

        v = V_THRESHOLD_0(intr_pktcount[0]) | V_THRESHOLD_1(intr_pktcount[1]) |
            V_THRESHOLD_2(intr_pktcount[2]) | V_THRESHOLD_3(intr_pktcount[3]);
        t4_write_reg(sc, A_SGE_INGRESS_RX_THRESHOLD, v);

        KASSERT(intr_timer[0] <= timer_max,
            ("%s: not a single usable timer (%d, %d)", __func__, intr_timer[0],
            timer_max));
        for (i = 1; i < nitems(intr_timer); i++) {
                KASSERT(intr_timer[i] >= intr_timer[i - 1],
                    ("%s: timers not listed in increasing order (%d)",
                    __func__, i));

                while (intr_timer[i] > timer_max) {
                        if (i == nitems(intr_timer) - 1) {
                                intr_timer[i] = timer_max;
                                break;
                        }
                        intr_timer[i] += intr_timer[i - 1];
                        intr_timer[i] /= 2;
                }
        }

        v = V_TIMERVALUE0(us_to_core_ticks(sc, intr_timer[0])) |
            V_TIMERVALUE1(us_to_core_ticks(sc, intr_timer[1]));
        t4_write_reg(sc, A_SGE_TIMER_VALUE_0_AND_1, v);
        v = V_TIMERVALUE2(us_to_core_ticks(sc, intr_timer[2])) |
            V_TIMERVALUE3(us_to_core_ticks(sc, intr_timer[3]));
        t4_write_reg(sc, A_SGE_TIMER_VALUE_2_AND_3, v);
        v = V_TIMERVALUE4(us_to_core_ticks(sc, intr_timer[4])) |
            V_TIMERVALUE5(us_to_core_ticks(sc, intr_timer[5]));
        t4_write_reg(sc, A_SGE_TIMER_VALUE_4_AND_5, v);

        if (chip_id(sc) >= CHELSIO_T6) {
                m = V_TSCALE(M_TSCALE);
                if (tscale == 1)
                        v = 0;
                else
                        v = V_TSCALE(tscale - 2);
                t4_set_reg_field(sc, A_SGE_ITP_CONTROL, m, v);

                if (sc->debug_flags & DF_DISABLE_TCB_CACHE) {
                        t4_tp_pio_read(sc, &v, 1, A_TP_CMM_CONFIG, 1);
                        if (chip_id(sc) >= CHELSIO_T7) {
                                v |= F_GLFL;
                        } else {
                                m = V_RDTHRESHOLD(M_RDTHRESHOLD) |
                                    F_WRTHRTHRESHEN |
                                    V_WRTHRTHRESH(M_WRTHRTHRESH);
                                v &= ~m;
                                v |= V_RDTHRESHOLD(1) | F_WRTHRTHRESHEN |
                                    V_WRTHRTHRESH(16);
                        }
                        t4_tp_pio_write(sc, &v, 1, A_TP_CMM_CONFIG, 1);
                }
        }

        /* 4K, 16K, 64K, 256K DDP "page sizes" for TDDP */
        v = V_HPZ0(0) | V_HPZ1(2) | V_HPZ2(4) | V_HPZ3(6);
        t4_write_reg(sc, A_ULP_RX_TDDP_PSZ, v);

        /*
         * 4K, 8K, 16K, 64K DDP "page sizes" for iSCSI DDP.  These have been
         * chosen with MAXPHYS = 128K in mind.  The largest DDP buffer that we
         * may have to deal with is MAXPHYS + 1 page.
         */
        v = V_HPZ0(0) | V_HPZ1(1) | V_HPZ2(2) | V_HPZ3(4);
        t4_write_reg(sc, A_ULP_RX_ISCSI_PSZ, v);

        /* We use multiple DDP page sizes both in plain-TOE and ISCSI modes. */
        m = v = F_TDDPTAGTCB | F_ISCSITAGTCB;
        if (sc->nvmecaps != 0) {
                /* Request DDP status bit for NVMe PDU completions. */
                m |= F_NVME_TCP_DDP_VAL_EN;
                v |= F_NVME_TCP_DDP_VAL_EN;
        }
        t4_set_reg_field(sc, A_ULP_RX_CTL, m, v);

        m = V_INDICATESIZE(M_INDICATESIZE) | F_REARMDDPOFFSET |
            F_RESETDDPOFFSET;
        v = V_INDICATESIZE(indsz) | F_REARMDDPOFFSET | F_RESETDDPOFFSET;
        t4_set_reg_field(sc, A_TP_PARA_REG5, m, v);
}

/*
 * SGE wants the buffer to be at least 64B and then a multiple of 16.  Its
 * address mut be 16B aligned.  If padding is in use the buffer's start and end
 * need to be aligned to the pad boundary as well.  We'll just make sure that
 * the size is a multiple of the pad boundary here, it is up to the buffer
 * allocation code to make sure the start of the buffer is aligned.
 */
static inline int
hwsz_ok(struct adapter *sc, int hwsz)
{
        int mask = fl_pad ? sc->params.sge.pad_boundary - 1 : 16 - 1;

        return (hwsz >= 64 && (hwsz & mask) == 0);
}

/*
 * Initialize the rx buffer sizes and figure out which zones the buffers will
 * be allocated from.
 */
void
t4_init_rx_buf_info(struct adapter *sc)
{
        struct sge *s = &sc->sge;
        struct sge_params *sp = &sc->params.sge;
        int i, j, n;
        static int sw_buf_sizes[] = {   /* Sorted by size */
                MCLBYTES,
#if MJUMPAGESIZE != MCLBYTES
                MJUMPAGESIZE,
#endif
                MJUM9BYTES,
                MJUM16BYTES
        };
        struct rx_buf_info *rxb;

        s->safe_zidx = -1;
        rxb = &s->rx_buf_info[0];
        for (i = 0; i < SW_ZONE_SIZES; i++, rxb++) {
                rxb->size1 = sw_buf_sizes[i];
                rxb->zone = m_getzone(rxb->size1);
                rxb->type = m_gettype(rxb->size1);
                rxb->size2 = 0;
                rxb->hwidx1 = -1;
                rxb->hwidx2 = -1;
                for (j = 0; j < SGE_FLBUF_SIZES; j++) {
                        int hwsize = sp->sge_fl_buffer_size[j];

                        if (!hwsz_ok(sc, hwsize))
                                continue;

                        /* hwidx for size1 */
                        if (rxb->hwidx1 == -1 && rxb->size1 == hwsize)
                                rxb->hwidx1 = j;

                        /* hwidx for size2 (buffer packing) */
                        if (rxb->size1 - CL_METADATA_SIZE < hwsize)
                                continue;
                        n = rxb->size1 - hwsize - CL_METADATA_SIZE;
                        if (n == 0) {
                                rxb->hwidx2 = j;
                                rxb->size2 = hwsize;
                                break;  /* stop looking */
                        }
                        if (rxb->hwidx2 != -1) {
                                if (n < sp->sge_fl_buffer_size[rxb->hwidx2] -
                                    hwsize - CL_METADATA_SIZE) {
                                        rxb->hwidx2 = j;
                                        rxb->size2 = hwsize;
                                }
                        } else if (n <= 2 * CL_METADATA_SIZE) {
                                rxb->hwidx2 = j;
                                rxb->size2 = hwsize;
                        }
                }
                if (rxb->hwidx2 != -1)
                        sc->flags |= BUF_PACKING_OK;
                if (s->safe_zidx == -1 && rxb->size1 == safest_rx_cluster)
                        s->safe_zidx = i;
        }
}

/*
 * Verify some basic SGE settings for the PF and VF driver, and other
 * miscellaneous settings for the PF driver.
 */
int
t4_verify_chip_settings(struct adapter *sc)
{
        struct sge_params *sp = &sc->params.sge;
        uint32_t m, v, r;
        int rc = 0;
        const uint16_t indsz = min(RX_COPY_THRESHOLD - 1, M_INDICATESIZE);

        m = F_RXPKTCPLMODE;
        v = F_RXPKTCPLMODE;
        r = sp->sge_control;
        if ((r & m) != v) {
                device_printf(sc->dev, "invalid SGE_CONTROL(0x%x)\n", r);
                rc = EINVAL;
        }

        /*
         * If this changes then every single use of PAGE_SHIFT in the driver
         * needs to be carefully reviewed for PAGE_SHIFT vs sp->page_shift.
         */
        if (sp->page_shift != PAGE_SHIFT) {
                device_printf(sc->dev, "invalid SGE_HOST_PAGE_SIZE(0x%x)\n", r);
                rc = EINVAL;
        }

        if (sc->flags & IS_VF)
                return (0);

        v = V_HPZ0(0) | V_HPZ1(2) | V_HPZ2(4) | V_HPZ3(6);
        r = t4_read_reg(sc, A_ULP_RX_TDDP_PSZ);
        if (r != v) {
                device_printf(sc->dev, "invalid ULP_RX_TDDP_PSZ(0x%x)\n", r);
                if (sc->vres.ddp.size != 0)
                        rc = EINVAL;
        }

        m = v = F_TDDPTAGTCB;
        r = t4_read_reg(sc, A_ULP_RX_CTL);
        if ((r & m) != v) {
                device_printf(sc->dev, "invalid ULP_RX_CTL(0x%x)\n", r);
                if (sc->vres.ddp.size != 0)
                        rc = EINVAL;
        }

        m = V_INDICATESIZE(M_INDICATESIZE) | F_REARMDDPOFFSET |
            F_RESETDDPOFFSET;
        v = V_INDICATESIZE(indsz) | F_REARMDDPOFFSET | F_RESETDDPOFFSET;
        r = t4_read_reg(sc, A_TP_PARA_REG5);
        if ((r & m) != v) {
                device_printf(sc->dev, "invalid TP_PARA_REG5(0x%x)\n", r);
                if (sc->vres.ddp.size != 0)
                        rc = EINVAL;
        }

        return (rc);
}

int
t4_create_dma_tag(struct adapter *sc)
{
        int rc;

        rc = bus_dma_tag_create(bus_get_dma_tag(sc->dev), 1, 0,
            BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL, BUS_SPACE_MAXSIZE,
            BUS_SPACE_UNRESTRICTED, BUS_SPACE_MAXSIZE, BUS_DMA_ALLOCNOW, NULL,
            NULL, &sc->dmat);
        if (rc != 0) {
                device_printf(sc->dev,
                    "failed to create main DMA tag: %d\n", rc);
        }

        return (rc);
}

void
t4_sge_sysctls(struct adapter *sc, struct sysctl_ctx_list *ctx,
    struct sysctl_oid_list *children)
{
        struct sge_params *sp = &sc->params.sge;

        SYSCTL_ADD_PROC(ctx, children, OID_AUTO, "buffer_sizes",
            CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, sc, 0,
            sysctl_bufsizes, "A", "freelist buffer sizes");

        SYSCTL_ADD_INT(ctx, children, OID_AUTO, "fl_pktshift", CTLFLAG_RD,
            NULL, sp->fl_pktshift, "payload DMA offset in rx buffer (bytes)");

        SYSCTL_ADD_INT(ctx, children, OID_AUTO, "fl_pad", CTLFLAG_RD,
            NULL, sp->pad_boundary, "payload pad boundary (bytes)");

        SYSCTL_ADD_INT(ctx, children, OID_AUTO, "spg_len", CTLFLAG_RD,
            NULL, sp->spg_len, "status page size (bytes)");

        SYSCTL_ADD_INT(ctx, children, OID_AUTO, "cong_drop", CTLFLAG_RD,
            NULL, cong_drop, "congestion drop setting");
#ifdef TCP_OFFLOAD
        SYSCTL_ADD_INT(ctx, children, OID_AUTO, "ofld_cong_drop", CTLFLAG_RD,
            NULL, ofld_cong_drop, "congestion drop setting");
#endif

        SYSCTL_ADD_INT(ctx, children, OID_AUTO, "fl_pack", CTLFLAG_RD,
            NULL, sp->pack_boundary, "payload pack boundary (bytes)");
}

int
t4_destroy_dma_tag(struct adapter *sc)
{
        if (sc->dmat)
                bus_dma_tag_destroy(sc->dmat);

        return (0);
}

/*
 * Allocate and initialize the firmware event queue, control queues, and special
 * purpose rx queues owned by the adapter.
 *
 * Returns errno on failure.  Resources allocated up to that point may still be
 * allocated.  Caller is responsible for cleanup in case this function fails.
 */
int
t4_setup_adapter_queues(struct adapter *sc)
{
        int rc, i;

        ADAPTER_LOCK_ASSERT_NOTOWNED(sc);

        /*
         * Firmware event queue
         */
        rc = alloc_fwq(sc);
        if (rc != 0)
                return (rc);

        /*
         * That's all for the VF driver.
         */
        if (sc->flags & IS_VF)
                return (rc);

        /*
         * XXX: General purpose rx queues, one per port.
         */

        /*
         * Control queues.  At least one per port and per internal core.
         */
        for (i = 0; i < sc->sge.nctrlq; i++) {
                rc = alloc_ctrlq(sc, i);
                if (rc != 0)
                        return (rc);
        }

        return (rc);
}

/*
 * Idempotent
 */
int
t4_teardown_adapter_queues(struct adapter *sc)
{
        int i;

        ADAPTER_LOCK_ASSERT_NOTOWNED(sc);

        if (sc->sge.ctrlq != NULL) {
                MPASS(!(sc->flags & IS_VF));    /* VFs don't allocate ctrlq. */
                for (i = 0; i < sc->sge.nctrlq; i++)
                        free_ctrlq(sc, i);
        }
        free_fwq(sc);

        return (0);
}

/* Maximum payload that could arrive with a single iq descriptor. */
static inline int
max_rx_payload(struct adapter *sc, if_t ifp, const bool ofld)
{
        int maxp;

        /* large enough even when hw VLAN extraction is disabled */
        maxp = sc->params.sge.fl_pktshift + ETHER_HDR_LEN +
            ETHER_VLAN_ENCAP_LEN + if_getmtu(ifp);
        if (ofld && sc->tt.tls && sc->cryptocaps & FW_CAPS_CONFIG_TLSKEYS &&
            maxp < sc->params.tp.max_rx_pdu)
                maxp = sc->params.tp.max_rx_pdu;
        return (maxp);
}

int
t4_setup_vi_queues(struct vi_info *vi)
{
        int rc = 0, i, intr_idx;
        struct sge_rxq *rxq;
        struct sge_txq *txq;
#ifdef TCP_OFFLOAD
        struct sge_ofld_rxq *ofld_rxq;
#endif
#if defined(TCP_OFFLOAD) || defined(RATELIMIT)
        struct sge_ofld_txq *ofld_txq;
#endif
#ifdef DEV_NETMAP
        int saved_idx, iqidx;
        struct sge_nm_rxq *nm_rxq;
        struct sge_nm_txq *nm_txq;
#endif
        struct adapter *sc = vi->adapter;
        if_t ifp = vi->ifp;
        int maxp;

        /* Interrupt vector to start from (when using multiple vectors) */
        intr_idx = vi->first_intr;

#ifdef DEV_NETMAP
        saved_idx = intr_idx;
        if (if_getcapabilities(ifp) & IFCAP_NETMAP) {

                /* netmap is supported with direct interrupts only. */
                MPASS(!forwarding_intr_to_fwq(sc));
                MPASS(vi->first_intr >= 0);

                /*
                 * We don't have buffers to back the netmap rx queues
                 * right now so we create the queues in a way that
                 * doesn't set off any congestion signal in the chip.
                 */
                for_each_nm_rxq(vi, i, nm_rxq) {
                        rc = alloc_nm_rxq(vi, nm_rxq, intr_idx, i);
                        if (rc != 0)
                                goto done;
                        intr_idx++;
                }

                for_each_nm_txq(vi, i, nm_txq) {
                        iqidx = vi->first_nm_rxq + (i % vi->nnmrxq);
                        rc = alloc_nm_txq(vi, nm_txq, iqidx, i);
                        if (rc != 0)
                                goto done;
                }
        }

        /* Normal rx queues and netmap rx queues share the same interrupts. */
        intr_idx = saved_idx;
#endif

        /*
         * Allocate rx queues first because a default iqid is required when
         * creating a tx queue.
         */
        maxp = max_rx_payload(sc, ifp, false);
        for_each_rxq(vi, i, rxq) {
                rc = alloc_rxq(vi, rxq, i, intr_idx, maxp);
                if (rc != 0)
                        goto done;
                if (!forwarding_intr_to_fwq(sc))
                        intr_idx++;
        }
#ifdef DEV_NETMAP
        if (if_getcapabilities(ifp) & IFCAP_NETMAP)
                intr_idx = saved_idx + max(vi->nrxq, vi->nnmrxq);
#endif
#ifdef TCP_OFFLOAD
        maxp = max_rx_payload(sc, ifp, true);
        for_each_ofld_rxq(vi, i, ofld_rxq) {
                rc = alloc_ofld_rxq(vi, ofld_rxq, i, intr_idx, maxp);
                if (rc != 0)
                        goto done;
                if (!forwarding_intr_to_fwq(sc))
                        intr_idx++;
        }
#endif

        /*
         * Now the tx queues.
         */
        for_each_txq(vi, i, txq) {
                rc = alloc_txq(vi, txq, i);
                if (rc != 0)
                        goto done;
        }
#if defined(TCP_OFFLOAD) || defined(RATELIMIT)
        for_each_ofld_txq(vi, i, ofld_txq) {
                rc = alloc_ofld_txq(vi, ofld_txq, i);
                if (rc != 0)
                        goto done;
        }
#endif
done:
        if (rc)
                t4_teardown_vi_queues(vi);

        return (rc);
}

/*
 * Idempotent
 */
int
t4_teardown_vi_queues(struct vi_info *vi)
{
        int i;
        struct sge_rxq *rxq;
        struct sge_txq *txq;
#if defined(TCP_OFFLOAD) || defined(RATELIMIT)
        struct sge_ofld_txq *ofld_txq;
#endif
#ifdef TCP_OFFLOAD
        struct sge_ofld_rxq *ofld_rxq;
#endif
#ifdef DEV_NETMAP
        struct sge_nm_rxq *nm_rxq;
        struct sge_nm_txq *nm_txq;
#endif

#ifdef DEV_NETMAP
        if (if_getcapabilities(vi->ifp) & IFCAP_NETMAP) {
                for_each_nm_txq(vi, i, nm_txq) {
                        free_nm_txq(vi, nm_txq);
                }

                for_each_nm_rxq(vi, i, nm_rxq) {
                        free_nm_rxq(vi, nm_rxq);
                }
        }
#endif

        /*
         * Take down all the tx queues first, as they reference the rx queues
         * (for egress updates, etc.).
         */

        for_each_txq(vi, i, txq) {
                free_txq(vi, txq);
        }
#if defined(TCP_OFFLOAD) || defined(RATELIMIT)
        for_each_ofld_txq(vi, i, ofld_txq) {
                free_ofld_txq(vi, ofld_txq);
        }
#endif

        /*
         * Then take down the rx queues.
         */

        for_each_rxq(vi, i, rxq) {
                free_rxq(vi, rxq);
        }
#ifdef TCP_OFFLOAD
        for_each_ofld_rxq(vi, i, ofld_rxq) {
                free_ofld_rxq(vi, ofld_rxq);
        }
#endif

        return (0);
}

/*
 * Interrupt handler when the driver is using only 1 interrupt.  This is a very
 * unusual scenario.
 *
 * a) Deals with errors, if any.
 * b) Services firmware event queue, which is taking interrupts for all other
 *    queues.
 */
void
t4_intr_all(void *arg)
{
        struct adapter *sc = arg;
        struct sge_iq *fwq = &sc->sge.fwq;

        MPASS(sc->intr_count == 1);

        if (sc->intr_type == INTR_INTX)
                t4_write_reg(sc, MYPF_REG(A_PCIE_PF_CLI), 0);

        t4_intr_err(arg);
        t4_intr_evt(fwq);
}

/*
 * Interrupt handler for errors (installed directly when multiple interrupts are
 * being used, or called by t4_intr_all).
 */
void
t4_intr_err(void *arg)
{
        struct adapter *sc = arg;
        uint32_t v;

        if (atomic_load_int(&sc->error_flags) & ADAP_FATAL_ERR)
                return;

        v = t4_read_reg(sc, MYPF_REG(A_PL_PF_INT_CAUSE));
        if (v & F_PFSW) {
                sc->swintr++;
                t4_write_reg(sc, MYPF_REG(A_PL_PF_INT_CAUSE), v);
        }

        if (t4_slow_intr_handler(sc, sc->intr_flags))
                t4_fatal_err(sc, false);
}

/*
 * Interrupt handler for iq-only queues.  The firmware event queue is the only
 * such queue right now.
 */
void
t4_intr_evt(void *arg)
{
        struct sge_iq *iq = arg;

        if (atomic_cmpset_int(&iq->state, IQS_IDLE, IQS_BUSY)) {
                service_iq(iq, 0);
                (void) atomic_cmpset_int(&iq->state, IQS_BUSY, IQS_IDLE);
        }
}

/*
 * Interrupt handler for iq+fl queues.
 */
void
t4_intr(void *arg)
{
        struct sge_iq *iq = arg;

        if (atomic_cmpset_int(&iq->state, IQS_IDLE, IQS_BUSY)) {
                service_iq_fl(iq, 0);
                (void) atomic_cmpset_int(&iq->state, IQS_BUSY, IQS_IDLE);
        }
}

#ifdef DEV_NETMAP
/*
 * Interrupt handler for netmap rx queues.
 */
void
t4_nm_intr(void *arg)
{
        struct sge_nm_rxq *nm_rxq = arg;

        if (atomic_cmpset_int(&nm_rxq->nm_state, NM_ON, NM_BUSY)) {
                service_nm_rxq(nm_rxq);
                (void) atomic_cmpset_int(&nm_rxq->nm_state, NM_BUSY, NM_ON);
        }
}

/*
 * Interrupt handler for vectors shared between NIC and netmap rx queues.
 */
void
t4_vi_intr(void *arg)
{
        struct irq *irq = arg;

        MPASS(irq->nm_rxq != NULL);
        t4_nm_intr(irq->nm_rxq);

        MPASS(irq->rxq != NULL);
        t4_intr(irq->rxq);
}
#endif

/*
 * Deals with interrupts on an iq-only (no freelist) queue.
 */
static int
service_iq(struct sge_iq *iq, int budget)
{
        struct sge_iq *q;
        struct adapter *sc = iq->adapter;
        struct iq_desc *d = &iq->desc[iq->cidx];
        int ndescs = 0, limit;
        int rsp_type;
        uint32_t lq;
        STAILQ_HEAD(, sge_iq) iql = STAILQ_HEAD_INITIALIZER(iql);

        KASSERT(iq->state == IQS_BUSY, ("%s: iq %p not BUSY", __func__, iq));
        KASSERT((iq->flags & IQ_HAS_FL) == 0,
            ("%s: called for iq %p with fl (iq->flags 0x%x)", __func__, iq,
            iq->flags));
        MPASS((iq->flags & IQ_ADJ_CREDIT) == 0);
        MPASS((iq->flags & IQ_LRO_ENABLED) == 0);

        limit = budget ? budget : iq->qsize / 16;

        /*
         * We always come back and check the descriptor ring for new indirect
         * interrupts and other responses after running a single handler.
         */
        for (;;) {
                while ((d->rsp.u.type_gen & F_RSPD_GEN) == iq->gen) {

                        rmb();

                        rsp_type = G_RSPD_TYPE(d->rsp.u.type_gen);
                        lq = be32toh(d->rsp.pldbuflen_qid);

                        switch (rsp_type) {
                        case X_RSPD_TYPE_FLBUF:
                                panic("%s: data for an iq (%p) with no freelist",
                                    __func__, iq);

                                /* NOTREACHED */

                        case X_RSPD_TYPE_CPL:
                                KASSERT(d->rss.opcode < NUM_CPL_CMDS,
                                    ("%s: bad opcode %02x.", __func__,
                                    d->rss.opcode));
                                t4_cpl_handler[d->rss.opcode](iq, &d->rss, NULL);
                                break;

                        case X_RSPD_TYPE_INTR:
                                /*
                                 * There are 1K interrupt-capable queues (qids 0
                                 * through 1023).  A response type indicating a
                                 * forwarded interrupt with a qid >= 1K is an
                                 * iWARP async notification.
                                 */
                                if (__predict_true(lq >= 1024)) {
                                        t4_an_handler(iq, &d->rsp);
                                        break;
                                }

                                q = sc->sge.iqmap[lq - sc->sge.iq_start -
                                    sc->sge.iq_base];
                                if (atomic_cmpset_int(&q->state, IQS_IDLE,
                                    IQS_BUSY)) {
                                        if (service_iq_fl(q, q->qsize / 16) == 0) {
                                                (void) atomic_cmpset_int(&q->state,
                                                    IQS_BUSY, IQS_IDLE);
                                        } else {
                                                STAILQ_INSERT_TAIL(&iql, q,
                                                    link);
                                        }
                                }
                                break;

                        default:
                                KASSERT(0,
                                    ("%s: illegal response type %d on iq %p",
                                    __func__, rsp_type, iq));
                                log(LOG_ERR,
                                    "%s: illegal response type %d on iq %p",
                                    device_get_nameunit(sc->dev), rsp_type, iq);
                                break;
                        }

                        d++;
                        if (__predict_false(++iq->cidx == iq->sidx)) {
                                iq->cidx = 0;
                                iq->gen ^= F_RSPD_GEN;
                                d = &iq->desc[0];
                        }
                        if (__predict_false(++ndescs == limit)) {
                                t4_write_reg(sc, sc->sge_gts_reg,
                                    V_CIDXINC(ndescs) |
                                    V_INGRESSQID(iq->cntxt_id) |
                                    V_SEINTARM(V_QINTR_TIMER_IDX(X_TIMERREG_UPDATE_CIDX)));
                                ndescs = 0;

                                if (budget) {
                                        return (EINPROGRESS);
                                }
                        }
                }

                if (STAILQ_EMPTY(&iql))
                        break;

                /*
                 * Process the head only, and send it to the back of the list if
                 * it's still not done.
                 */
                q = STAILQ_FIRST(&iql);
                STAILQ_REMOVE_HEAD(&iql, link);
                if (service_iq_fl(q, q->qsize / 8) == 0)
                        (void) atomic_cmpset_int(&q->state, IQS_BUSY, IQS_IDLE);
                else
                        STAILQ_INSERT_TAIL(&iql, q, link);
        }

        t4_write_reg(sc, sc->sge_gts_reg, V_CIDXINC(ndescs) |
            V_INGRESSQID((u32)iq->cntxt_id) | V_SEINTARM(iq->intr_params));

        return (0);
}

#if defined(INET) || defined(INET6)
static inline int
sort_before_lro(struct lro_ctrl *lro)
{

        return (lro->lro_mbuf_max != 0);
}
#endif

static inline uint64_t
t4_tstmp_to_ns(struct adapter *sc, uint64_t hw_tstmp)
{
        struct clock_sync *cur, dcur;
        uint64_t hw_clocks;
        uint64_t hw_clk_div;
        sbintime_t sbt_cur_to_prev, sbt;
        seqc_t gen;

        for (;;) {
                cur = &sc->cal_info[sc->cal_current];
                gen = seqc_read(&cur->gen);
                if (gen == 0)
                        return (0);
                dcur = *cur;
                if (seqc_consistent(&cur->gen, gen))
                        break;
        }

        /*
         * Our goal here is to have a result that is:
         *
         * (                             (cur_time - prev_time)   )
         * ((hw_tstmp - hw_prev) *  ----------------------------- ) + prev_time
         * (                             (hw_cur - hw_prev)       )
         *
         * With the constraints that we cannot use float and we
         * don't want to overflow the uint64_t numbers we are using.
         */
        hw_clocks = hw_tstmp - dcur.hw_prev;
        sbt_cur_to_prev = (dcur.sbt_cur - dcur.sbt_prev);
        hw_clk_div = dcur.hw_cur - dcur.hw_prev;
        sbt = hw_clocks * sbt_cur_to_prev / hw_clk_div + dcur.sbt_prev;
        return (sbttons(sbt));
}

static inline void
move_to_next_rxbuf(struct sge_fl *fl)
{

        fl->rx_offset = 0;
        if (__predict_false((++fl->cidx & 7) == 0)) {
                uint16_t cidx = fl->cidx >> 3;

                if (__predict_false(cidx == fl->sidx))
                        fl->cidx = cidx = 0;
                fl->hw_cidx = cidx;
        }
}

/*
 * Deals with interrupts on an iq+fl queue.
 */
static int
service_iq_fl(struct sge_iq *iq, int budget)
{
        struct sge_rxq *rxq = iq_to_rxq(iq);
        struct sge_fl *fl;
        struct adapter *sc = iq->adapter;
        struct iq_desc *d = &iq->desc[iq->cidx];
        int ndescs, limit;
        int rsp_type, starved;
        uint32_t lq;
        uint16_t fl_hw_cidx;
        struct mbuf *m0;
#if defined(INET) || defined(INET6)
        const struct timeval lro_timeout = {0, sc->lro_timeout};
        struct lro_ctrl *lro = &rxq->lro;
#endif

        KASSERT(iq->state == IQS_BUSY, ("%s: iq %p not BUSY", __func__, iq));
        MPASS(iq->flags & IQ_HAS_FL);

        ndescs = 0;
#if defined(INET) || defined(INET6)
        if (iq->flags & IQ_ADJ_CREDIT) {
                MPASS(sort_before_lro(lro));
                iq->flags &= ~IQ_ADJ_CREDIT;
                if ((d->rsp.u.type_gen & F_RSPD_GEN) != iq->gen) {
                        tcp_lro_flush_all(lro);
                        t4_write_reg(sc, sc->sge_gts_reg, V_CIDXINC(1) |
                            V_INGRESSQID((u32)iq->cntxt_id) |
                            V_SEINTARM(iq->intr_params));
                        return (0);
                }
                ndescs = 1;
        }
#else
        MPASS((iq->flags & IQ_ADJ_CREDIT) == 0);
#endif

        limit = budget ? budget : iq->qsize / 16;
        fl = &rxq->fl;
        fl_hw_cidx = fl->hw_cidx;       /* stable snapshot */
        while ((d->rsp.u.type_gen & F_RSPD_GEN) == iq->gen) {

                rmb();

                m0 = NULL;
                rsp_type = G_RSPD_TYPE(d->rsp.u.type_gen);
                lq = be32toh(d->rsp.pldbuflen_qid);

                switch (rsp_type) {
                case X_RSPD_TYPE_FLBUF:
                        if (lq & F_RSPD_NEWBUF) {
                                if (fl->rx_offset > 0)
                                        move_to_next_rxbuf(fl);
                                lq = G_RSPD_LEN(lq);
                        }
                        if (IDXDIFF(fl->hw_cidx, fl_hw_cidx, fl->sidx) > 4) {
                                FL_LOCK(fl);
                                refill_fl(sc, fl, 64);
                                FL_UNLOCK(fl);
                                fl_hw_cidx = fl->hw_cidx;
                        }

                        if (d->rss.opcode == CPL_RX_PKT) {
                                if (__predict_true(eth_rx(sc, rxq, d, lq) == 0))
                                        break;
                                goto out;
                        }
                        m0 = get_fl_payload(sc, fl, lq);
                        if (__predict_false(m0 == NULL))
                                goto out;

                        /* fall through */

                case X_RSPD_TYPE_CPL:
                        KASSERT(d->rss.opcode < NUM_CPL_CMDS,
                            ("%s: bad opcode %02x.", __func__, d->rss.opcode));
                        t4_cpl_handler[d->rss.opcode](iq, &d->rss, m0);
                        break;

                case X_RSPD_TYPE_INTR:

                        /*
                         * There are 1K interrupt-capable queues (qids 0
                         * through 1023).  A response type indicating a
                         * forwarded interrupt with a qid >= 1K is an
                         * iWARP async notification.  That is the only
                         * acceptable indirect interrupt on this queue.
                         */
                        if (__predict_false(lq < 1024)) {
                                panic("%s: indirect interrupt on iq_fl %p "
                                    "with qid %u", __func__, iq, lq);
                        }

                        t4_an_handler(iq, &d->rsp);
                        break;

                default:
                        KASSERT(0, ("%s: illegal response type %d on iq %p",
                            __func__, rsp_type, iq));
                        log(LOG_ERR, "%s: illegal response type %d on iq %p",
                            device_get_nameunit(sc->dev), rsp_type, iq);
                        break;
                }

                d++;
                if (__predict_false(++iq->cidx == iq->sidx)) {
                        iq->cidx = 0;
                        iq->gen ^= F_RSPD_GEN;
                        d = &iq->desc[0];
                }
                if (__predict_false(++ndescs == limit)) {
                        t4_write_reg(sc, sc->sge_gts_reg, V_CIDXINC(ndescs) |
                            V_INGRESSQID(iq->cntxt_id) |
                            V_SEINTARM(V_QINTR_TIMER_IDX(X_TIMERREG_UPDATE_CIDX)));

#if defined(INET) || defined(INET6)
                        if (iq->flags & IQ_LRO_ENABLED &&
                            !sort_before_lro(lro) &&
                            sc->lro_timeout != 0) {
                                tcp_lro_flush_inactive(lro, &lro_timeout);
                        }
#endif
                        if (budget)
                                return (EINPROGRESS);
                        ndescs = 0;
                }
        }
out:
#if defined(INET) || defined(INET6)
        if (iq->flags & IQ_LRO_ENABLED) {
                if (ndescs > 0 && lro->lro_mbuf_count > 8) {
                        MPASS(sort_before_lro(lro));
                        /* hold back one credit and don't flush LRO state */
                        iq->flags |= IQ_ADJ_CREDIT;
                        ndescs--;
                } else {
                        tcp_lro_flush_all(lro);
                }
        }
#endif

        t4_write_reg(sc, sc->sge_gts_reg, V_CIDXINC(ndescs) |
            V_INGRESSQID((u32)iq->cntxt_id) | V_SEINTARM(iq->intr_params));

        FL_LOCK(fl);
        starved = refill_fl(sc, fl, 64);
        FL_UNLOCK(fl);
        if (__predict_false(starved != 0))
                add_fl_to_sfl(sc, fl);

        return (0);
}

static inline struct cluster_metadata *
cl_metadata(struct fl_sdesc *sd)
{

        return ((void *)(sd->cl + sd->moff));
}

static void
rxb_free(struct mbuf *m)
{
        struct cluster_metadata *clm = m->m_ext.ext_arg1;

        uma_zfree(clm->zone, clm->cl);
        counter_u64_add(extfree_rels, 1);
}

/*
 * The mbuf returned comes from zone_muf and carries the payload in one of these
 * ways
 * a) complete frame inside the mbuf
 * b) m_cljset (for clusters without metadata)
 * d) m_extaddref (cluster with metadata)
 */
static struct mbuf *
get_scatter_segment(struct adapter *sc, struct sge_fl *fl, int fr_offset,
    int remaining)
{
        struct mbuf *m;
        struct fl_sdesc *sd = &fl->sdesc[fl->cidx];
        struct rx_buf_info *rxb = &sc->sge.rx_buf_info[sd->zidx];
        struct cluster_metadata *clm;
        int len, blen;
        caddr_t payload;

        if (fl->flags & FL_BUF_PACKING) {
                u_int l, pad;

                blen = rxb->size2 - fl->rx_offset;      /* max possible in this buf */
                len = min(remaining, blen);
                payload = sd->cl + fl->rx_offset;

                l = fr_offset + len;
                pad = roundup2(l, fl->buf_boundary) - l;
                if (fl->rx_offset + len + pad < rxb->size2)
                        blen = len + pad;
                MPASS(fl->rx_offset + blen <= rxb->size2);
        } else {
                MPASS(fl->rx_offset == 0);      /* not packing */
                blen = rxb->size1;
                len = min(remaining, blen);
                payload = sd->cl;
        }

        if (fr_offset == 0) {
                m = m_gethdr(M_NOWAIT, MT_DATA);
                if (__predict_false(m == NULL))
                        return (NULL);
                m->m_pkthdr.len = remaining;
        } else {
                m = m_get(M_NOWAIT, MT_DATA);
                if (__predict_false(m == NULL))
                        return (NULL);
        }
        m->m_len = len;
        kmsan_mark(payload, len, KMSAN_STATE_INITED);

        if (sc->sc_do_rxcopy && len < RX_COPY_THRESHOLD) {
                /* copy data to mbuf */
                bcopy(payload, mtod(m, caddr_t), len);
                if (fl->flags & FL_BUF_PACKING) {
                        fl->rx_offset += blen;
                        MPASS(fl->rx_offset <= rxb->size2);
                        if (fl->rx_offset < rxb->size2)
                                return (m);     /* without advancing the cidx */
                }
        } else if (fl->flags & FL_BUF_PACKING) {
                clm = cl_metadata(sd);
                if (sd->nmbuf++ == 0) {
                        clm->refcount = 1;
                        clm->zone = rxb->zone;
                        clm->cl = sd->cl;
                        counter_u64_add(extfree_refs, 1);
                }
                m_extaddref(m, payload, blen, &clm->refcount, rxb_free, clm,
                    NULL);

                fl->rx_offset += blen;
                MPASS(fl->rx_offset <= rxb->size2);
                if (fl->rx_offset < rxb->size2)
                        return (m);     /* without advancing the cidx */
        } else {
                m_cljset(m, sd->cl, rxb->type);
                sd->cl = NULL;  /* consumed, not a recycle candidate */
        }

        move_to_next_rxbuf(fl);

        return (m);
}

static struct mbuf *
get_fl_payload(struct adapter *sc, struct sge_fl *fl, const u_int plen)
{
        struct mbuf *m0, *m, **pnext;
        u_int remaining;

        if (__predict_false(fl->flags & FL_BUF_RESUME)) {
                M_ASSERTPKTHDR(fl->m0);
                MPASS(fl->m0->m_pkthdr.len == plen);
                MPASS(fl->remaining < plen);

                m0 = fl->m0;
                pnext = fl->pnext;
                remaining = fl->remaining;
                fl->flags &= ~FL_BUF_RESUME;
                goto get_segment;
        }

        /*
         * Payload starts at rx_offset in the current hw buffer.  Its length is
         * 'len' and it may span multiple hw buffers.
         */

        m0 = get_scatter_segment(sc, fl, 0, plen);
        if (m0 == NULL)
                return (NULL);
        remaining = plen - m0->m_len;
        pnext = &m0->m_next;
        while (remaining > 0) {
get_segment:
                MPASS(fl->rx_offset == 0);
                m = get_scatter_segment(sc, fl, plen - remaining, remaining);
                if (__predict_false(m == NULL)) {
                        fl->m0 = m0;
                        fl->pnext = pnext;
                        fl->remaining = remaining;
                        fl->flags |= FL_BUF_RESUME;
                        return (NULL);
                }
                *pnext = m;
                pnext = &m->m_next;
                remaining -= m->m_len;
        }
        *pnext = NULL;

        M_ASSERTPKTHDR(m0);
        return (m0);
}

static int
skip_scatter_segment(struct adapter *sc, struct sge_fl *fl, int fr_offset,
    int remaining)
{
        struct fl_sdesc *sd = &fl->sdesc[fl->cidx];
        struct rx_buf_info *rxb = &sc->sge.rx_buf_info[sd->zidx];
        int len, blen;

        if (fl->flags & FL_BUF_PACKING) {
                u_int l, pad;

                blen = rxb->size2 - fl->rx_offset;      /* max possible in this buf */
                len = min(remaining, blen);

                l = fr_offset + len;
                pad = roundup2(l, fl->buf_boundary) - l;
                if (fl->rx_offset + len + pad < rxb->size2)
                        blen = len + pad;
                fl->rx_offset += blen;
                MPASS(fl->rx_offset <= rxb->size2);
                if (fl->rx_offset < rxb->size2)
                        return (len);   /* without advancing the cidx */
        } else {
                MPASS(fl->rx_offset == 0);      /* not packing */
                blen = rxb->size1;
                len = min(remaining, blen);
        }
        move_to_next_rxbuf(fl);
        return (len);
}

static inline void
skip_fl_payload(struct adapter *sc, struct sge_fl *fl, int plen)
{
        int remaining, fr_offset, len;

        fr_offset = 0;
        remaining = plen;
        while (remaining > 0) {
                len = skip_scatter_segment(sc, fl, fr_offset, remaining);
                fr_offset += len;
                remaining -= len;
        }
}

static inline int
get_segment_len(struct adapter *sc, struct sge_fl *fl, int plen)
{
        int len;
        struct fl_sdesc *sd = &fl->sdesc[fl->cidx];
        struct rx_buf_info *rxb = &sc->sge.rx_buf_info[sd->zidx];

        if (fl->flags & FL_BUF_PACKING)
                len = rxb->size2 - fl->rx_offset;
        else
                len = rxb->size1;

        return (min(plen, len));
}

static void
handle_cpl_rx_pkt(struct adapter *sc, struct sge_rxq *rxq,
    const struct cpl_rx_pkt *cpl, struct mbuf *m0)
{
        if_t ifp = rxq->ifp;
        uint16_t err_vec, tnl_type, tnlhdr_len;
        static const int sw_csum_flags[2][2] = {
                {
                        /* IP, inner IP */
                        CSUM_ENCAP_VXLAN |
                            CSUM_L3_CALC | CSUM_L3_VALID |
                            CSUM_L4_CALC | CSUM_L4_VALID |
                            CSUM_INNER_L3_CALC | CSUM_INNER_L3_VALID |
                            CSUM_INNER_L4_CALC | CSUM_INNER_L4_VALID,

                        /* IP, inner IP6 */
                        CSUM_ENCAP_VXLAN |
                            CSUM_L3_CALC | CSUM_L3_VALID |
                            CSUM_L4_CALC | CSUM_L4_VALID |
                            CSUM_INNER_L4_CALC | CSUM_INNER_L4_VALID,
                },
                {
                        /* IP6, inner IP */
                        CSUM_ENCAP_VXLAN |
                            CSUM_L4_CALC | CSUM_L4_VALID |
                            CSUM_INNER_L3_CALC | CSUM_INNER_L3_VALID |
                            CSUM_INNER_L4_CALC | CSUM_INNER_L4_VALID,

                        /* IP6, inner IP6 */
                        CSUM_ENCAP_VXLAN |
                            CSUM_L4_CALC | CSUM_L4_VALID |
                            CSUM_INNER_L4_CALC | CSUM_INNER_L4_VALID,
                },
        };

        if (sc->params.tp.rx_pkt_encap) {
                const uint16_t ev = be16toh(cpl->err_vec);

                err_vec = G_T6_COMPR_RXERR_VEC(ev);
                tnl_type = G_T6_RX_TNL_TYPE(ev);
                tnlhdr_len = G_T6_RX_TNLHDR_LEN(ev);
        } else {
                err_vec = be16toh(cpl->err_vec);
                tnl_type = 0;
                tnlhdr_len = 0;
        }
        if (cpl->csum_calc && err_vec == 0) {
                int ipv6 = !!(cpl->l2info & htobe32(F_RXF_IP6));

                /* checksum(s) calculated and found to be correct. */

                MPASS((cpl->l2info & htobe32(F_RXF_IP)) ^
                    (cpl->l2info & htobe32(F_RXF_IP6)));
                m0->m_pkthdr.csum_data = be16toh(cpl->csum);
                if (tnl_type == 0) {
                        if (!ipv6 && if_getcapenable(ifp) & IFCAP_RXCSUM) {
                                m0->m_pkthdr.csum_flags = CSUM_L3_CALC |
                                    CSUM_L3_VALID | CSUM_L4_CALC |
                                    CSUM_L4_VALID;
                        } else if (ipv6 && if_getcapenable(ifp) & IFCAP_RXCSUM_IPV6) {
                                m0->m_pkthdr.csum_flags = CSUM_L4_CALC |
                                    CSUM_L4_VALID;
                        }
                        rxq->rxcsum++;
                } else {
                        MPASS(tnl_type == RX_PKT_TNL_TYPE_VXLAN);

                        M_HASHTYPE_SETINNER(m0);
                        if (__predict_false(cpl->ip_frag)) {
                                /*
                                 * csum_data is for the inner frame (which is an
                                 * IP fragment) and is not 0xffff.  There is no
                                 * way to pass the inner csum_data to the stack.
                                 * We don't want the stack to use the inner
                                 * csum_data to validate the outer frame or it
                                 * will get rejected.  So we fix csum_data here
                                 * and let sw do the checksum of inner IP
                                 * fragments.
                                 *
                                 * XXX: Need 32b for csum_data2 in an rx mbuf.
                                 * Maybe stuff it into rcv_tstmp?
                                 */
                                m0->m_pkthdr.csum_data = 0xffff;
                                if (ipv6) {
                                        m0->m_pkthdr.csum_flags = CSUM_L4_CALC |
                                            CSUM_L4_VALID;
                                } else {
                                        m0->m_pkthdr.csum_flags = CSUM_L3_CALC |
                                            CSUM_L3_VALID | CSUM_L4_CALC |
                                            CSUM_L4_VALID;
                                }
                        } else {
                                int outer_ipv6;

                                MPASS(m0->m_pkthdr.csum_data == 0xffff);

                                outer_ipv6 = tnlhdr_len >=
                                    sizeof(struct ether_header) +
                                    sizeof(struct ip6_hdr);
                                m0->m_pkthdr.csum_flags =
                                    sw_csum_flags[outer_ipv6][ipv6];
                        }
                        rxq->vxlan_rxcsum++;
                }
        }

        if (cpl->vlan_ex) {
                if (sc->flags & IS_VF && sc->vlan_id) {
                        /*
                         * HW is not setup correctly if extracted vlan_id does
                         * not match the VF's setting.
                         */
                        MPASS(be16toh(cpl->vlan) == sc->vlan_id);
                } else {
                        m0->m_pkthdr.ether_vtag = be16toh(cpl->vlan);
                        m0->m_flags |= M_VLANTAG;
                        rxq->vlan_extraction++;
                }
        }
}

static int
eth_rx(struct adapter *sc, struct sge_rxq *rxq, const struct iq_desc *d,
    u_int plen)
{
        struct mbuf *m0;
        if_t ifp = rxq->ifp;
        struct sge_fl *fl = &rxq->fl;
        struct vi_info *vi = if_getsoftc(ifp);
#if defined(INET) || defined(INET6)
        struct lro_ctrl *lro = &rxq->lro;
#endif
        int rc;
        const uint8_t fl_pktshift = sc->params.sge.fl_pktshift;
        static const uint8_t sw_hashtype[4][2] = {
                {M_HASHTYPE_NONE, M_HASHTYPE_NONE},
                {M_HASHTYPE_RSS_IPV4, M_HASHTYPE_RSS_IPV6},
                {M_HASHTYPE_RSS_TCP_IPV4, M_HASHTYPE_RSS_TCP_IPV6},
                {M_HASHTYPE_RSS_UDP_IPV4, M_HASHTYPE_RSS_UDP_IPV6},
        };

        MPASS(plen > fl_pktshift);
        if (vi->pfil != NULL && PFIL_HOOKED_IN(vi->pfil) &&
            __predict_true((fl->flags & FL_BUF_RESUME) == 0)) {
                struct fl_sdesc *sd = &fl->sdesc[fl->cidx];
                caddr_t frame;
                const int slen = get_segment_len(sc, fl, plen) - fl_pktshift;

                frame = sd->cl + fl->rx_offset + fl_pktshift;
                CURVNET_SET_QUIET(if_getvnet(ifp));
                rc = pfil_mem_in(vi->pfil, frame, slen, ifp, &m0);
                CURVNET_RESTORE();
                if (rc == PFIL_DROPPED || rc == PFIL_CONSUMED) {
                        skip_fl_payload(sc, fl, plen);
                        return (0);
                }
                if (rc == PFIL_REALLOCED) {
                        skip_fl_payload(sc, fl, plen);
                        goto have_mbuf;
                }
        }

        m0 = get_fl_payload(sc, fl, plen);
        if (__predict_false(m0 == NULL))
                return (ENOMEM);
        m0->m_pkthdr.len -= fl_pktshift;
        m0->m_len -= fl_pktshift;
        m0->m_data += fl_pktshift;

have_mbuf:
        m0->m_pkthdr.rcvif = ifp;
        M_HASHTYPE_SET(m0, sw_hashtype[d->rss.hash_type][d->rss.ipv6]);
        m0->m_pkthdr.flowid = be32toh(d->rss.hash_val);
#ifdef NUMA
        m0->m_pkthdr.numa_domain = if_getnumadomain(ifp);
#endif
        if (rxq->iq.flags & IQ_RX_TIMESTAMP) {
                /*
                 * Fill up rcv_tstmp and set M_TSTMP if we get a a non-zero back
                 * from t4_tstmp_to_ns().  The descriptor has a 60b timestamp.
                 */
                m0->m_pkthdr.rcv_tstmp = t4_tstmp_to_ns(sc,
                    be64toh(d->rsp.u.last_flit) & 0x0fffffffffffffffULL);
                if (m0->m_pkthdr.rcv_tstmp != 0)
                        m0->m_flags |= M_TSTMP;
        }

        handle_cpl_rx_pkt(sc, rxq, (const void *)(&d->rss + 1), m0);

#if defined(INET) || defined(INET6)
        if (rxq->iq.flags & IQ_LRO_ENABLED &&
            (m0->m_pkthdr.rsstype & M_HASHTYPE_INNER) == 0 &&
            (M_HASHTYPE_GET(m0) == M_HASHTYPE_RSS_TCP_IPV4 ||
            M_HASHTYPE_GET(m0) == M_HASHTYPE_RSS_TCP_IPV6)) {
                if (sort_before_lro(lro)) {
                        tcp_lro_queue_mbuf(lro, m0);
                        return (0); /* queued for sort, then LRO */
                }
                if (tcp_lro_rx(lro, m0, 0) == 0)
                        return (0); /* queued for LRO */
        }
#endif
        if_input(ifp, m0);

        return (0);
}

/*
 * Must drain the wrq or make sure that someone else will.
 */
static void
wrq_tx_drain(void *arg, int n)
{
        struct sge_wrq *wrq = arg;
        struct sge_eq *eq = &wrq->eq;

        EQ_LOCK(eq);
        if (TAILQ_EMPTY(&wrq->incomplete_wrs) && !STAILQ_EMPTY(&wrq->wr_list))
                drain_wrq_wr_list(wrq->adapter, wrq);
        EQ_UNLOCK(eq);
}

static void
drain_wrq_wr_list(struct adapter *sc, struct sge_wrq *wrq)
{
        struct sge_eq *eq = &wrq->eq;
        u_int available, dbdiff;        /* # of hardware descriptors */
        u_int n;
        struct wrqe *wr;
        struct fw_eth_tx_pkt_wr *dst;   /* any fw WR struct will do */

        EQ_LOCK_ASSERT_OWNED(eq);
        MPASS(TAILQ_EMPTY(&wrq->incomplete_wrs));
        wr = STAILQ_FIRST(&wrq->wr_list);
        MPASS(wr != NULL);      /* Must be called with something useful to do */
        MPASS(eq->pidx == eq->dbidx);
        dbdiff = 0;

        do {
                eq->cidx = read_hw_cidx(eq);
                if (eq->pidx == eq->cidx)
                        available = eq->sidx - 1;
                else
                        available = IDXDIFF(eq->cidx, eq->pidx, eq->sidx) - 1;

                MPASS(wr->wrq == wrq);
                n = howmany(wr->wr_len, EQ_ESIZE);
                if (available < n)
                        break;

                dst = (void *)&eq->desc[eq->pidx];
                if (__predict_true(eq->sidx - eq->pidx > n)) {
                        /* Won't wrap, won't end exactly at the status page. */
                        bcopy(&wr->wr[0], dst, wr->wr_len);
                        eq->pidx += n;
                } else {
                        int first_portion = (eq->sidx - eq->pidx) * EQ_ESIZE;

                        bcopy(&wr->wr[0], dst, first_portion);
                        if (wr->wr_len > first_portion) {
                                bcopy(&wr->wr[first_portion], &eq->desc[0],
                                    wr->wr_len - first_portion);
                        }
                        eq->pidx = n - (eq->sidx - eq->pidx);
                }
                wrq->tx_wrs_copied++;

                if (available < eq->sidx / 4 &&
                    atomic_cmpset_int(&eq->equiq, 0, 1)) {
                                /*
                                 * XXX: This is not 100% reliable with some
                                 * types of WRs.  But this is a very unusual
                                 * situation for an ofld/ctrl queue anyway.
                                 */
                        dst->equiq_to_len16 |= htobe32(F_FW_WR_EQUIQ |
                            F_FW_WR_EQUEQ);
                }

                dbdiff += n;
                if (dbdiff >= 16) {
                        ring_eq_db(sc, eq, dbdiff);
                        dbdiff = 0;
                }

                STAILQ_REMOVE_HEAD(&wrq->wr_list, link);
                free_wrqe(wr);
                MPASS(wrq->nwr_pending > 0);
                wrq->nwr_pending--;
                MPASS(wrq->ndesc_needed >= n);
                wrq->ndesc_needed -= n;
        } while ((wr = STAILQ_FIRST(&wrq->wr_list)) != NULL);

        if (dbdiff)
                ring_eq_db(sc, eq, dbdiff);
}

/*
 * Doesn't fail.  Holds on to work requests it can't send right away.
 */
void
t4_wrq_tx_locked(struct adapter *sc, struct sge_wrq *wrq, struct wrqe *wr)
{
#ifdef INVARIANTS
        struct sge_eq *eq = &wrq->eq;
#endif

        EQ_LOCK_ASSERT_OWNED(eq);
        MPASS(wr != NULL);
        MPASS(wr->wr_len > 0 && wr->wr_len <= SGE_MAX_WR_LEN);
        MPASS((wr->wr_len & 0x7) == 0);

        STAILQ_INSERT_TAIL(&wrq->wr_list, wr, link);
        wrq->nwr_pending++;
        wrq->ndesc_needed += howmany(wr->wr_len, EQ_ESIZE);

        if (!TAILQ_EMPTY(&wrq->incomplete_wrs))
                return; /* commit_wrq_wr will drain wr_list as well. */

        drain_wrq_wr_list(sc, wrq);

        /* Doorbell must have caught up to the pidx. */
        MPASS(eq->pidx == eq->dbidx);
}

void
t4_update_fl_bufsize(if_t ifp)
{
        struct vi_info *vi = if_getsoftc(ifp);
        struct adapter *sc = vi->adapter;
        struct sge_rxq *rxq;
#ifdef TCP_OFFLOAD
        struct sge_ofld_rxq *ofld_rxq;
#endif
        struct sge_fl *fl;
        int i, maxp;

        maxp = max_rx_payload(sc, ifp, false);
        for_each_rxq(vi, i, rxq) {
                fl = &rxq->fl;

                FL_LOCK(fl);
                fl->zidx = find_refill_source(sc, maxp,
                    fl->flags & FL_BUF_PACKING);
                FL_UNLOCK(fl);
        }
#ifdef TCP_OFFLOAD
        maxp = max_rx_payload(sc, ifp, true);
        for_each_ofld_rxq(vi, i, ofld_rxq) {
                fl = &ofld_rxq->fl;

                FL_LOCK(fl);
                fl->zidx = find_refill_source(sc, maxp,
                    fl->flags & FL_BUF_PACKING);
                FL_UNLOCK(fl);
        }
#endif
}

#ifdef RATELIMIT
static inline int
mbuf_eo_nsegs(struct mbuf *m)
{

        M_ASSERTPKTHDR(m);
        return (m->m_pkthdr.PH_loc.eight[1]);
}

#if defined(INET) || defined(INET6)
static inline void
set_mbuf_eo_nsegs(struct mbuf *m, uint8_t nsegs)
{

        M_ASSERTPKTHDR(m);
        m->m_pkthdr.PH_loc.eight[1] = nsegs;
}
#endif

static inline int
mbuf_eo_len16(struct mbuf *m)
{
        int n;

        M_ASSERTPKTHDR(m);
        n = m->m_pkthdr.PH_loc.eight[2];
        MPASS(n > 0 && n <= SGE_MAX_WR_LEN / 16);

        return (n);
}

#if defined(INET) || defined(INET6)
static inline void
set_mbuf_eo_len16(struct mbuf *m, uint8_t len16)
{

        M_ASSERTPKTHDR(m);
        m->m_pkthdr.PH_loc.eight[2] = len16;
}
#endif

static inline int
mbuf_eo_tsclk_tsoff(struct mbuf *m)
{

        M_ASSERTPKTHDR(m);
        return (m->m_pkthdr.PH_loc.eight[3]);
}

#if defined(INET) || defined(INET6)
static inline void
set_mbuf_eo_tsclk_tsoff(struct mbuf *m, uint8_t tsclk_tsoff)
{

        M_ASSERTPKTHDR(m);
        m->m_pkthdr.PH_loc.eight[3] = tsclk_tsoff;
}
#endif

static inline int
needs_eo(struct m_snd_tag *mst)
{

        return (mst != NULL && mst->sw->type == IF_SND_TAG_TYPE_RATE_LIMIT);
}
#endif

/*
 * Try to allocate an mbuf to contain a raw work request.  To make it
 * easy to construct the work request, don't allocate a chain but a
 * single mbuf.
 */
struct mbuf *
alloc_wr_mbuf(int len, int how)
{
        struct mbuf *m;

        if (len <= MHLEN)
                m = m_gethdr(how, MT_DATA);
        else if (len <= MCLBYTES)
                m = m_getcl(how, MT_DATA, M_PKTHDR);
        else
                m = NULL;
        if (m == NULL)
                return (NULL);
        m->m_pkthdr.len = len;
        m->m_len = len;
        set_mbuf_cflags(m, MC_RAW_WR);
        set_mbuf_len16(m, howmany(len, 16));
        return (m);
}

static inline bool
needs_hwcsum(struct mbuf *m)
{
        const uint32_t csum_flags = CSUM_IP | CSUM_IP_UDP | CSUM_IP_TCP |
            CSUM_IP_TSO | CSUM_INNER_IP | CSUM_INNER_IP_UDP |
            CSUM_INNER_IP_TCP | CSUM_INNER_IP_TSO | CSUM_IP6_UDP |
            CSUM_IP6_TCP | CSUM_IP6_TSO | CSUM_INNER_IP6_UDP |
            CSUM_INNER_IP6_TCP | CSUM_INNER_IP6_TSO;

        M_ASSERTPKTHDR(m);

        return (m->m_pkthdr.csum_flags & csum_flags);
}

static inline bool
needs_tso(struct mbuf *m)
{
        const uint32_t csum_flags = CSUM_IP_TSO | CSUM_IP6_TSO |
            CSUM_INNER_IP_TSO | CSUM_INNER_IP6_TSO;

        M_ASSERTPKTHDR(m);

        return (m->m_pkthdr.csum_flags & csum_flags);
}

static inline bool
needs_vxlan_csum(struct mbuf *m)
{

        M_ASSERTPKTHDR(m);

        return (m->m_pkthdr.csum_flags & CSUM_ENCAP_VXLAN);
}

static inline bool
needs_vxlan_tso(struct mbuf *m)
{
        const uint32_t csum_flags = CSUM_ENCAP_VXLAN | CSUM_INNER_IP_TSO |
            CSUM_INNER_IP6_TSO;

        M_ASSERTPKTHDR(m);

        return ((m->m_pkthdr.csum_flags & csum_flags) != 0 &&
            (m->m_pkthdr.csum_flags & csum_flags) != CSUM_ENCAP_VXLAN);
}

#if defined(INET) || defined(INET6)
static inline bool
needs_inner_tcp_csum(struct mbuf *m)
{
        const uint32_t csum_flags = CSUM_INNER_IP_TSO | CSUM_INNER_IP6_TSO;

        M_ASSERTPKTHDR(m);

        return (m->m_pkthdr.csum_flags & csum_flags);
}
#endif

static inline bool
needs_l3_csum(struct mbuf *m)
{
        const uint32_t csum_flags = CSUM_IP | CSUM_IP_TSO | CSUM_INNER_IP |
            CSUM_INNER_IP_TSO;

        M_ASSERTPKTHDR(m);

        return (m->m_pkthdr.csum_flags & csum_flags);
}

static inline bool
needs_outer_tcp_csum(struct mbuf *m)
{
        const uint32_t csum_flags = CSUM_IP_TCP | CSUM_IP_TSO | CSUM_IP6_TCP |
            CSUM_IP6_TSO;

        M_ASSERTPKTHDR(m);

        return (m->m_pkthdr.csum_flags & csum_flags);
}

#ifdef RATELIMIT
static inline bool
needs_outer_l4_csum(struct mbuf *m)
{
        const uint32_t csum_flags = CSUM_IP_UDP | CSUM_IP_TCP | CSUM_IP_TSO |
            CSUM_IP6_UDP | CSUM_IP6_TCP | CSUM_IP6_TSO;

        M_ASSERTPKTHDR(m);

        return (m->m_pkthdr.csum_flags & csum_flags);
}

static inline bool
needs_outer_udp_csum(struct mbuf *m)
{
        const uint32_t csum_flags = CSUM_IP_UDP | CSUM_IP6_UDP;

        M_ASSERTPKTHDR(m);

        return (m->m_pkthdr.csum_flags & csum_flags);
}
#endif

static inline bool
needs_vlan_insertion(struct mbuf *m)
{

        M_ASSERTPKTHDR(m);

        return (m->m_flags & M_VLANTAG);
}

#if defined(INET) || defined(INET6)
static void *
m_advance(struct mbuf **pm, int *poffset, int len)
{
        struct mbuf *m = *pm;
        int offset = *poffset;
        uintptr_t p = 0;

        MPASS(len > 0);

        for (;;) {
                if (offset + len < m->m_len) {
                        offset += len;
                        p = mtod(m, uintptr_t) + offset;
                        break;
                }
                len -= m->m_len - offset;
                m = m->m_next;
                offset = 0;
                MPASS(m != NULL);
        }
        *poffset = offset;
        *pm = m;
        return ((void *)p);
}
#endif

static inline int
count_mbuf_ext_pgs(struct mbuf *m, int skip, vm_paddr_t *nextaddr)
{
        vm_paddr_t paddr;
        int i, len, off, pglen, pgoff, seglen, segoff;
        int nsegs = 0;

        M_ASSERTEXTPG(m);
        off = mtod(m, vm_offset_t);
        len = m->m_len;
        off += skip;
        len -= skip;

        if (m->m_epg_hdrlen != 0) {
                if (off >= m->m_epg_hdrlen) {
                        off -= m->m_epg_hdrlen;
                } else {
                        seglen = m->m_epg_hdrlen - off;
                        segoff = off;
                        seglen = min(seglen, len);
                        off = 0;
                        len -= seglen;
                        paddr = pmap_kextract(
                            (vm_offset_t)&m->m_epg_hdr[segoff]);
                        if (*nextaddr != paddr)
                                nsegs++;
                        *nextaddr = paddr + seglen;
                }
        }
        pgoff = m->m_epg_1st_off;
        for (i = 0; i < m->m_epg_npgs && len > 0; i++) {
                pglen = m_epg_pagelen(m, i, pgoff);
                if (off >= pglen) {
                        off -= pglen;
                        pgoff = 0;
                        continue;
                }
                seglen = pglen - off;
                segoff = pgoff + off;
                off = 0;
                seglen = min(seglen, len);
                len -= seglen;
                paddr = m->m_epg_pa[i] + segoff;
                if (*nextaddr != paddr)
                        nsegs++;
                *nextaddr = paddr + seglen;
                pgoff = 0;
        };
        if (len != 0) {
                seglen = min(len, m->m_epg_trllen - off);
                len -= seglen;
                paddr = pmap_kextract((vm_offset_t)&m->m_epg_trail[off]);
                if (*nextaddr != paddr)
                        nsegs++;
                *nextaddr = paddr + seglen;
        }

        return (nsegs);
}


/*
 * Can deal with empty mbufs in the chain that have m_len = 0, but the chain
 * must have at least one mbuf that's not empty.  It is possible for this
 * routine to return 0 if skip accounts for all the contents of the mbuf chain.
 */
static inline int
count_mbuf_nsegs(struct mbuf *m, int skip, uint8_t *cflags)
{
        vm_paddr_t nextaddr, paddr;
        vm_offset_t va;
        int len, nsegs;

        M_ASSERTPKTHDR(m);
        MPASS(m->m_pkthdr.len > 0);
        MPASS(m->m_pkthdr.len >= skip);

        nsegs = 0;
        nextaddr = 0;
        for (; m; m = m->m_next) {
                len = m->m_len;
                if (__predict_false(len == 0))
                        continue;
                if (skip >= len) {
                        skip -= len;
                        continue;
                }
                if ((m->m_flags & M_EXTPG) != 0) {
                        *cflags |= MC_NOMAP;
                        nsegs += count_mbuf_ext_pgs(m, skip, &nextaddr);
                        skip = 0;
                        continue;
                }
                va = mtod(m, vm_offset_t) + skip;
                len -= skip;
                skip = 0;
                paddr = pmap_kextract(va);
                nsegs += sglist_count((void *)(uintptr_t)va, len);
                if (paddr == nextaddr)
                        nsegs--;
                nextaddr = pmap_kextract(va + len - 1) + 1;
        }

        return (nsegs);
}

/*
 * The maximum number of segments that can fit in a WR.
 */
static int
max_nsegs_allowed(struct mbuf *m, bool vm_wr)
{

        if (vm_wr) {
                if (needs_tso(m))
                        return (TX_SGL_SEGS_VM_TSO);
                return (TX_SGL_SEGS_VM);
        }

        if (needs_tso(m)) {
                if (needs_vxlan_tso(m))
                        return (TX_SGL_SEGS_VXLAN_TSO);
                else
                        return (TX_SGL_SEGS_TSO);
        }

        return (TX_SGL_SEGS);
}

static struct timeval txerr_ratecheck = {0};
static const struct timeval txerr_interval = {3, 0};

/*
 * Analyze the mbuf to determine its tx needs.  The mbuf passed in may change:
 * a) caller can assume it's been freed if this function returns with an error.
 * b) it may get defragged up if the gather list is too long for the hardware.
 */
int
parse_pkt(struct mbuf **mp, bool vm_wr)
{
        struct mbuf *m0 = *mp, *m;
        int rc, nsegs, defragged = 0;
        struct ether_header *eh;
#ifdef INET
        void *l3hdr;
#endif
#if defined(INET) || defined(INET6)
        int offset;
        struct tcphdr *tcp;
#endif
#if defined(KERN_TLS) || defined(RATELIMIT)
        struct m_snd_tag *mst;
#endif
        uint16_t eh_type;
        uint8_t cflags;

        cflags = 0;
        M_ASSERTPKTHDR(m0);
        if (__predict_false(m0->m_pkthdr.len < ETHER_HDR_LEN)) {
                rc = EINVAL;
fail:
                m_freem(m0);
                *mp = NULL;
                return (rc);
        }
restart:
        /*
         * First count the number of gather list segments in the payload.
         * Defrag the mbuf if nsegs exceeds the hardware limit.
         */
        M_ASSERTPKTHDR(m0);
        MPASS(m0->m_pkthdr.len > 0);
        nsegs = count_mbuf_nsegs(m0, 0, &cflags);
#if defined(KERN_TLS) || defined(RATELIMIT)
        if (m0->m_pkthdr.csum_flags & CSUM_SND_TAG)
                mst = m0->m_pkthdr.snd_tag;
        else
                mst = NULL;
#endif
#ifdef KERN_TLS
        if (mst != NULL && mst->sw->type == IF_SND_TAG_TYPE_TLS) {
                struct vi_info *vi = if_getsoftc(mst->ifp);

                cflags |= MC_TLS;
                set_mbuf_cflags(m0, cflags);
                if (is_t6(vi->pi->adapter))
                        rc = t6_ktls_parse_pkt(m0);
                else
                        rc = t7_ktls_parse_pkt(m0);
                if (rc != 0)
                        goto fail;
                return (EINPROGRESS);
        }
#endif
        if (nsegs > max_nsegs_allowed(m0, vm_wr)) {
                if (defragged++ > 0) {
                        rc = EFBIG;
                        goto fail;
                }
                counter_u64_add(defrags, 1);
                if ((m = m_defrag(m0, M_NOWAIT)) == NULL) {
                        rc = ENOMEM;
                        goto fail;
                }
                *mp = m0 = m;   /* update caller's copy after defrag */
                goto restart;
        }

        if (__predict_false(nsegs > 2 && m0->m_pkthdr.len <= MHLEN &&
            !(cflags & MC_NOMAP))) {
                counter_u64_add(pullups, 1);
                m0 = m_pullup(m0, m0->m_pkthdr.len);
                if (m0 == NULL) {
                        /* Should have left well enough alone. */
                        rc = EFBIG;
                        goto fail;
                }
                *mp = m0;       /* update caller's copy after pullup */
                goto restart;
        }
        set_mbuf_nsegs(m0, nsegs);
        set_mbuf_cflags(m0, cflags);
        calculate_mbuf_len16(m0, vm_wr);

#ifdef RATELIMIT
        /*
         * Ethofld is limited to TCP and UDP for now, and only when L4 hw
         * checksumming is enabled.  needs_outer_l4_csum happens to check for
         * all the right things.
         */
        if (__predict_false(needs_eo(mst) && !needs_outer_l4_csum(m0))) {
                m_snd_tag_rele(m0->m_pkthdr.snd_tag);
                m0->m_pkthdr.snd_tag = NULL;
                m0->m_pkthdr.csum_flags &= ~CSUM_SND_TAG;
                mst = NULL;
        }
#endif

        if (!needs_hwcsum(m0)
#ifdef RATELIMIT
                 && !needs_eo(mst)
#endif
        )
                return (0);

        m = m0;
        eh = mtod(m, struct ether_header *);
        eh_type = ntohs(eh->ether_type);
        if (eh_type == ETHERTYPE_VLAN) {
                struct ether_vlan_header *evh = (void *)eh;

                eh_type = ntohs(evh->evl_proto);
                m0->m_pkthdr.l2hlen = sizeof(*evh);
        } else
                m0->m_pkthdr.l2hlen = sizeof(*eh);

#if defined(INET) || defined(INET6)
        offset = 0;
#ifdef INET
        l3hdr = m_advance(&m, &offset, m0->m_pkthdr.l2hlen);
#else
        m_advance(&m, &offset, m0->m_pkthdr.l2hlen);
#endif
#endif

        switch (eh_type) {
#ifdef INET6
        case ETHERTYPE_IPV6:
                m0->m_pkthdr.l3hlen = sizeof(struct ip6_hdr);
                break;
#endif
#ifdef INET
        case ETHERTYPE_IP:
        {
                struct ip *ip = l3hdr;

                if (needs_vxlan_csum(m0)) {
                        /* Driver will do the outer IP hdr checksum. */
                        ip->ip_sum = 0;
                        if (needs_vxlan_tso(m0)) {
                                const uint16_t ipl = ip->ip_len;

                                ip->ip_len = 0;
                                ip->ip_sum = ~in_cksum_hdr(ip);
                                ip->ip_len = ipl;
                        } else
                                ip->ip_sum = in_cksum_hdr(ip);
                }
                m0->m_pkthdr.l3hlen = ip->ip_hl << 2;
                break;
        }
#endif
        default:
                if (ratecheck(&txerr_ratecheck, &txerr_interval)) {
                        log(LOG_ERR, "%s: ethertype 0x%04x unknown.  "
                            "if_cxgbe must be compiled with the same "
                            "INET/INET6 options as the kernel.\n", __func__,
                            eh_type);
                }
                rc = EINVAL;
                goto fail;
        }

#if defined(INET) || defined(INET6)
        if (needs_vxlan_csum(m0)) {
                m0->m_pkthdr.l4hlen = sizeof(struct udphdr);
                m0->m_pkthdr.l5hlen = sizeof(struct vxlan_header);

                /* Inner headers. */
                eh = m_advance(&m, &offset, m0->m_pkthdr.l3hlen +
                    sizeof(struct udphdr) + sizeof(struct vxlan_header));
                eh_type = ntohs(eh->ether_type);
                if (eh_type == ETHERTYPE_VLAN) {
                        struct ether_vlan_header *evh = (void *)eh;

                        eh_type = ntohs(evh->evl_proto);
                        m0->m_pkthdr.inner_l2hlen = sizeof(*evh);
                } else
                        m0->m_pkthdr.inner_l2hlen = sizeof(*eh);
#ifdef INET
                l3hdr = m_advance(&m, &offset, m0->m_pkthdr.inner_l2hlen);
#else
                m_advance(&m, &offset, m0->m_pkthdr.inner_l2hlen);
#endif

                switch (eh_type) {
#ifdef INET6
                case ETHERTYPE_IPV6:
                        m0->m_pkthdr.inner_l3hlen = sizeof(struct ip6_hdr);
                        break;
#endif
#ifdef INET
                case ETHERTYPE_IP:
                {
                        struct ip *ip = l3hdr;

                        m0->m_pkthdr.inner_l3hlen = ip->ip_hl << 2;
                        break;
                }
#endif
                default:
                        if (ratecheck(&txerr_ratecheck, &txerr_interval)) {
                                log(LOG_ERR, "%s: VXLAN hw offload requested"
                                    "with unknown ethertype 0x%04x.  if_cxgbe "
                                    "must be compiled with the same INET/INET6 "
                                    "options as the kernel.\n", __func__,
                                    eh_type);
                        }
                        rc = EINVAL;
                        goto fail;
                }
                if (needs_inner_tcp_csum(m0)) {
                        tcp = m_advance(&m, &offset, m0->m_pkthdr.inner_l3hlen);
                        m0->m_pkthdr.inner_l4hlen = tcp->th_off * 4;
                }
                MPASS((m0->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0);
                m0->m_pkthdr.csum_flags &= CSUM_INNER_IP6_UDP |
                    CSUM_INNER_IP6_TCP | CSUM_INNER_IP6_TSO | CSUM_INNER_IP |
                    CSUM_INNER_IP_UDP | CSUM_INNER_IP_TCP | CSUM_INNER_IP_TSO |
                    CSUM_ENCAP_VXLAN;
        }

        if (needs_outer_tcp_csum(m0)) {
                tcp = m_advance(&m, &offset, m0->m_pkthdr.l3hlen);
                m0->m_pkthdr.l4hlen = tcp->th_off * 4;
#ifdef RATELIMIT
                if (tsclk >= 0 && *(uint32_t *)(tcp + 1) == ntohl(0x0101080a)) {
                        set_mbuf_eo_tsclk_tsoff(m0,
                            V_FW_ETH_TX_EO_WR_TSCLK(tsclk) |
                            V_FW_ETH_TX_EO_WR_TSOFF(sizeof(*tcp) / 2 + 1));
                } else
                        set_mbuf_eo_tsclk_tsoff(m0, 0);
        } else if (needs_outer_udp_csum(m0)) {
                m0->m_pkthdr.l4hlen = sizeof(struct udphdr);
#endif
        }
#ifdef RATELIMIT
        if (needs_eo(mst)) {
                u_int immhdrs;

                /* EO WRs have the headers in the WR and not the GL. */
                immhdrs = m0->m_pkthdr.l2hlen + m0->m_pkthdr.l3hlen +
                    m0->m_pkthdr.l4hlen;
                cflags = 0;
                nsegs = count_mbuf_nsegs(m0, immhdrs, &cflags);
                MPASS(cflags == mbuf_cflags(m0));
                set_mbuf_eo_nsegs(m0, nsegs);
                set_mbuf_eo_len16(m0,
                    txpkt_eo_len16(nsegs, immhdrs, needs_tso(m0)));
                rc = ethofld_transmit(mst->ifp, m0);
                if (rc != 0)
                        goto fail;
                return (EINPROGRESS);
        }
#endif
#endif
        MPASS(m0 == *mp);
        return (0);
}

void *
start_wrq_wr(struct sge_wrq *wrq, int len16, struct wrq_cookie *cookie)
{
        struct sge_eq *eq = &wrq->eq;
        struct adapter *sc = wrq->adapter;
        int ndesc, available;
        struct wrqe *wr;
        void *w;

        MPASS(len16 > 0);
        ndesc = tx_len16_to_desc(len16);
        MPASS(ndesc > 0 && ndesc <= SGE_MAX_WR_NDESC);

        EQ_LOCK(eq);
        if (__predict_false((eq->flags & EQ_HW_ALLOCATED) == 0)) {
                EQ_UNLOCK(eq);
                return (NULL);
        }

        if (TAILQ_EMPTY(&wrq->incomplete_wrs) && !STAILQ_EMPTY(&wrq->wr_list))
                drain_wrq_wr_list(sc, wrq);

        if (!STAILQ_EMPTY(&wrq->wr_list)) {
slowpath:
                EQ_UNLOCK(eq);
                wr = alloc_wrqe(len16 * 16, wrq);
                if (__predict_false(wr == NULL))
                        return (NULL);
                cookie->pidx = -1;
                cookie->ndesc = ndesc;
                return (&wr->wr);
        }

        eq->cidx = read_hw_cidx(eq);
        if (eq->pidx == eq->cidx)
                available = eq->sidx - 1;
        else
                available = IDXDIFF(eq->cidx, eq->pidx, eq->sidx) - 1;
        if (available < ndesc)
                goto slowpath;

        cookie->pidx = eq->pidx;
        cookie->ndesc = ndesc;
        TAILQ_INSERT_TAIL(&wrq->incomplete_wrs, cookie, link);

        w = &eq->desc[eq->pidx];
        IDXINCR(eq->pidx, ndesc, eq->sidx);
        if (__predict_false(cookie->pidx + ndesc > eq->sidx)) {
                w = &wrq->ss[0];
                wrq->ss_pidx = cookie->pidx;
                wrq->ss_len = len16 * 16;
        }

        EQ_UNLOCK(eq);

        return (w);
}

void
commit_wrq_wr(struct sge_wrq *wrq, void *w, struct wrq_cookie *cookie)
{
        struct sge_eq *eq = &wrq->eq;
        struct adapter *sc = wrq->adapter;
        int ndesc, pidx;
        struct wrq_cookie *prev, *next;

        if (cookie->pidx == -1) {
                struct wrqe *wr = __containerof(w, struct wrqe, wr);

                t4_wrq_tx(sc, wr);
                return;
        }

        if (__predict_false(w == &wrq->ss[0])) {
                int n = (eq->sidx - wrq->ss_pidx) * EQ_ESIZE;

                MPASS(wrq->ss_len > n); /* WR had better wrap around. */
                bcopy(&wrq->ss[0], &eq->desc[wrq->ss_pidx], n);
                bcopy(&wrq->ss[n], &eq->desc[0], wrq->ss_len - n);
                wrq->tx_wrs_ss++;
        } else
                wrq->tx_wrs_direct++;

        EQ_LOCK(eq);
        ndesc = cookie->ndesc;  /* Can be more than SGE_MAX_WR_NDESC here. */
        pidx = cookie->pidx;
        MPASS(pidx >= 0 && pidx < eq->sidx);
        prev = TAILQ_PREV(cookie, wrq_incomplete_wrs, link);
        next = TAILQ_NEXT(cookie, link);
        if (prev == NULL) {
                MPASS(pidx == eq->dbidx);
                if (next == NULL || ndesc >= 16) {
                        int available;
                        struct fw_eth_tx_pkt_wr *dst;   /* any fw WR struct will do */

                        /*
                         * Note that the WR via which we'll request tx updates
                         * is at pidx and not eq->pidx, which has moved on
                         * already.
                         */
                        dst = (void *)&eq->desc[pidx];
                        available = IDXDIFF(eq->cidx, eq->pidx, eq->sidx) - 1;
                        if (available < eq->sidx / 4 &&
                            atomic_cmpset_int(&eq->equiq, 0, 1)) {
                                /*
                                 * XXX: This is not 100% reliable with some
                                 * types of WRs.  But this is a very unusual
                                 * situation for an ofld/ctrl queue anyway.
                                 */
                                dst->equiq_to_len16 |= htobe32(F_FW_WR_EQUIQ |
                                    F_FW_WR_EQUEQ);
                        }

                        if (__predict_true(eq->flags & EQ_HW_ALLOCATED))
                                ring_eq_db(wrq->adapter, eq, ndesc);
                        else
                                IDXINCR(eq->dbidx, ndesc, eq->sidx);
                } else {
                        MPASS(IDXDIFF(next->pidx, pidx, eq->sidx) == ndesc);
                        next->pidx = pidx;
                        next->ndesc += ndesc;
                }
        } else {
                MPASS(IDXDIFF(pidx, prev->pidx, eq->sidx) == prev->ndesc);
                prev->ndesc += ndesc;
        }
        TAILQ_REMOVE(&wrq->incomplete_wrs, cookie, link);

        if (TAILQ_EMPTY(&wrq->incomplete_wrs) && !STAILQ_EMPTY(&wrq->wr_list))
                drain_wrq_wr_list(sc, wrq);

#ifdef INVARIANTS
        if (TAILQ_EMPTY(&wrq->incomplete_wrs)) {
                /* Doorbell must have caught up to the pidx. */
                MPASS(wrq->eq.pidx == wrq->eq.dbidx);
        }
#endif
        EQ_UNLOCK(eq);
}

static u_int
can_resume_eth_tx(struct mp_ring *r)
{
        struct sge_eq *eq = r->cookie;

        return (total_available_tx_desc(eq) > eq->sidx / 8);
}

static inline bool
cannot_use_txpkts(struct mbuf *m)
{
        /* maybe put a GL limit too, to avoid silliness? */

        return (needs_tso(m) || (mbuf_cflags(m) & (MC_RAW_WR | MC_TLS)) != 0);
}

static inline int
discard_tx(struct sge_eq *eq)
{

        return ((eq->flags & (EQ_ENABLED | EQ_QFLUSH)) != EQ_ENABLED);
}

static inline int
wr_can_update_eq(void *p)
{
        struct fw_eth_tx_pkts_wr *wr = p;

        switch (G_FW_WR_OP(be32toh(wr->op_pkd))) {
        case FW_ULPTX_WR:
        case FW_ETH_TX_PKT_WR:
        case FW_ETH_TX_PKTS_WR:
        case FW_ETH_TX_PKTS2_WR:
        case FW_ETH_TX_PKT_VM_WR:
        case FW_ETH_TX_PKTS_VM_WR:
                return (1);
        default:
                return (0);
        }
}

static inline void
set_txupdate_flags(struct sge_txq *txq, u_int avail,
    struct fw_eth_tx_pkt_wr *wr)
{
        struct sge_eq *eq = &txq->eq;
        struct txpkts *txp = &txq->txp;

        if ((txp->npkt > 0 || avail < eq->sidx / 2) &&
            atomic_cmpset_int(&eq->equiq, 0, 1)) {
                wr->equiq_to_len16 |= htobe32(F_FW_WR_EQUEQ | F_FW_WR_EQUIQ);
                eq->equeqidx = eq->pidx;
        } else if (IDXDIFF(eq->pidx, eq->equeqidx, eq->sidx) >= 32) {
                wr->equiq_to_len16 |= htobe32(F_FW_WR_EQUEQ);
                eq->equeqidx = eq->pidx;
        }
}

#if defined(__i386__) || defined(__amd64__)
extern uint64_t tsc_freq;
#endif

static inline bool
record_eth_tx_time(struct sge_txq *txq)
{
        const uint64_t cycles = get_cyclecount();
        const uint64_t last_tx = txq->last_tx;
#if defined(__i386__) || defined(__amd64__)
        const uint64_t itg = tsc_freq * t4_tx_coalesce_gap / 1000000;
#else
        const uint64_t itg = 0;
#endif

        MPASS(cycles >= last_tx);
        txq->last_tx = cycles;
        return (cycles - last_tx < itg);
}

/*
 * r->items[cidx] to r->items[pidx], with a wraparound at r->size, are ready to
 * be consumed.  Return the actual number consumed.  0 indicates a stall.
 */
static u_int
eth_tx(struct mp_ring *r, u_int cidx, u_int pidx, bool *coalescing)
{
        struct sge_txq *txq = r->cookie;
        if_t ifp = txq->ifp;
        struct sge_eq *eq = &txq->eq;
        struct txpkts *txp = &txq->txp;
        struct vi_info *vi = if_getsoftc(ifp);
        struct adapter *sc = vi->adapter;
        u_int total, remaining;         /* # of packets */
        u_int n, avail, dbdiff;         /* # of hardware descriptors */
        int i, rc;
        struct mbuf *m0;
        bool snd, recent_tx;
        void *wr;       /* start of the last WR written to the ring */

        TXQ_LOCK_ASSERT_OWNED(txq);
        recent_tx = record_eth_tx_time(txq);

        remaining = IDXDIFF(pidx, cidx, r->size);
        if (__predict_false(discard_tx(eq))) {
                for (i = 0; i < txp->npkt; i++)
                        m_freem(txp->mb[i]);
                txp->npkt = 0;
                while (cidx != pidx) {
                        m0 = r->items[cidx];
                        m_freem(m0);
                        if (++cidx == r->size)
                                cidx = 0;
                }
                reclaim_tx_descs(txq, eq->sidx);
                *coalescing = false;
                return (remaining);     /* emptied */
        }

        /* How many hardware descriptors do we have readily available. */
        if (eq->pidx == eq->cidx)
                avail = eq->sidx - 1;
        else
                avail = IDXDIFF(eq->cidx, eq->pidx, eq->sidx) - 1;

        total = 0;
        if (remaining == 0) {
                txp->score = 0;
                txq->txpkts_flush++;
                goto send_txpkts;
        }

        dbdiff = 0;
        MPASS(remaining > 0);
        while (remaining > 0) {
                m0 = r->items[cidx];
                M_ASSERTPKTHDR(m0);
                MPASS(m0->m_nextpkt == NULL);

                if (avail < 2 * SGE_MAX_WR_NDESC)
                        avail += reclaim_tx_descs(txq, 64);

                if (t4_tx_coalesce == 0 && txp->npkt == 0)
                        goto skip_coalescing;
                if (cannot_use_txpkts(m0))
                        txp->score = 0;
                else if (recent_tx) {
                        if (++txp->score == 0)
                                txp->score = UINT8_MAX;
                } else
                        txp->score = 1;
                if (txp->npkt > 0 || remaining > 1 ||
                    txp->score >= t4_tx_coalesce_pkts ||
                    atomic_load_int(&txq->eq.equiq) != 0) {
                        if (vi->flags & TX_USES_VM_WR)
                                rc = add_to_txpkts_vf(sc, txq, m0, avail, &snd);
                        else
                                rc = add_to_txpkts_pf(sc, txq, m0, avail, &snd);
                } else {
                        snd = false;
                        rc = EINVAL;
                }
                if (snd) {
                        MPASS(txp->npkt > 0);
                        for (i = 0; i < txp->npkt; i++)
                                ETHER_BPF_MTAP(ifp, txp->mb[i]);
                        if (txp->npkt > 1) {
                                MPASS(avail >= tx_len16_to_desc(txp->len16));
                                if (vi->flags & TX_USES_VM_WR)
                                        n = write_txpkts_vm_wr(sc, txq);
                                else
                                        n = write_txpkts_wr(sc, txq);
                        } else {
                                MPASS(avail >=
                                    tx_len16_to_desc(mbuf_len16(txp->mb[0])));
                                if (vi->flags & TX_USES_VM_WR)
                                        n = write_txpkt_vm_wr(sc, txq,
                                            txp->mb[0]);
                                else
                                        n = write_txpkt_wr(sc, txq, txp->mb[0],
                                            avail);
                        }
                        MPASS(n <= SGE_MAX_WR_NDESC);
                        avail -= n;
                        dbdiff += n;
                        wr = &eq->desc[eq->pidx];
                        IDXINCR(eq->pidx, n, eq->sidx);
                        txp->npkt = 0;  /* emptied */
                }
                if (rc == 0) {
                        /* m0 was coalesced into txq->txpkts. */
                        goto next_mbuf;
                }
                if (rc == EAGAIN) {
                        /*
                         * m0 is suitable for tx coalescing but could not be
                         * combined with the existing txq->txpkts, which has now
                         * been transmitted.  Start a new txpkts with m0.
                         */
                        MPASS(snd);
                        MPASS(txp->npkt == 0);
                        continue;
                }

                MPASS(rc != 0 && rc != EAGAIN);
                MPASS(txp->npkt == 0);
skip_coalescing:
                n = tx_len16_to_desc(mbuf_len16(m0));
                if (__predict_false(avail < n)) {
                        avail += reclaim_tx_descs(txq, min(n, 32));
                        if (avail < n)
                                break;  /* out of descriptors */
                }

                wr = &eq->desc[eq->pidx];
                if (mbuf_cflags(m0) & MC_RAW_WR) {
                        n = write_raw_wr(txq, wr, m0, avail);
#ifdef KERN_TLS
                } else if (mbuf_cflags(m0) & MC_TLS) {
                        ETHER_BPF_MTAP(ifp, m0);
                        if (is_t6(sc))
                                n = t6_ktls_write_wr(txq, wr, m0, avail);
                        else
                                n = t7_ktls_write_wr(txq, wr, m0, avail);
#endif
                } else {
                        ETHER_BPF_MTAP(ifp, m0);
                        if (vi->flags & TX_USES_VM_WR)
                                n = write_txpkt_vm_wr(sc, txq, m0);
                        else
                                n = write_txpkt_wr(sc, txq, m0, avail);
                }
                MPASS(n >= 1 && n <= avail);
                if (!(mbuf_cflags(m0) & MC_TLS))
                        MPASS(n <= SGE_MAX_WR_NDESC);

                avail -= n;
                dbdiff += n;
                IDXINCR(eq->pidx, n, eq->sidx);

                if (dbdiff >= 512 / EQ_ESIZE) { /* X_FETCHBURSTMAX_512B */
                        if (wr_can_update_eq(wr))
                                set_txupdate_flags(txq, avail, wr);
                        ring_eq_db(sc, eq, dbdiff);
                        avail += reclaim_tx_descs(txq, 32);
                        dbdiff = 0;
                }
next_mbuf:
                total++;
                remaining--;
                if (__predict_false(++cidx == r->size))
                        cidx = 0;
        }
        if (dbdiff != 0) {
                if (wr_can_update_eq(wr))
                        set_txupdate_flags(txq, avail, wr);
                ring_eq_db(sc, eq, dbdiff);
                reclaim_tx_descs(txq, 32);
        } else if (eq->pidx == eq->cidx && txp->npkt > 0 &&
            atomic_load_int(&txq->eq.equiq) == 0) {
                /*
                 * If nothing was submitted to the chip for tx (it was coalesced
                 * into txpkts instead) and there is no tx update outstanding
                 * then we need to send txpkts now.
                 */
send_txpkts:
                MPASS(txp->npkt > 0);
                for (i = 0; i < txp->npkt; i++)
                        ETHER_BPF_MTAP(ifp, txp->mb[i]);
                if (txp->npkt > 1) {
                        MPASS(avail >= tx_len16_to_desc(txp->len16));
                        if (vi->flags & TX_USES_VM_WR)
                                n = write_txpkts_vm_wr(sc, txq);
                        else
                                n = write_txpkts_wr(sc, txq);
                } else {
                        MPASS(avail >=
                            tx_len16_to_desc(mbuf_len16(txp->mb[0])));
                        if (vi->flags & TX_USES_VM_WR)
                                n = write_txpkt_vm_wr(sc, txq, txp->mb[0]);
                        else
                                n = write_txpkt_wr(sc, txq, txp->mb[0], avail);
                }
                MPASS(n <= SGE_MAX_WR_NDESC);
                wr = &eq->desc[eq->pidx];
                IDXINCR(eq->pidx, n, eq->sidx);
                txp->npkt = 0;  /* emptied */

                MPASS(wr_can_update_eq(wr));
                set_txupdate_flags(txq, avail - n, wr);
                ring_eq_db(sc, eq, n);
                reclaim_tx_descs(txq, 32);
        }
        *coalescing = txp->npkt > 0;

        return (total);
}

static inline void
init_iq(struct sge_iq *iq, struct adapter *sc, int tmr_idx, int pktc_idx,
    int qsize, int intr_idx, int cong, int qtype)
{

        KASSERT(tmr_idx >= 0 && tmr_idx < SGE_NTIMERS,
            ("%s: bad tmr_idx %d", __func__, tmr_idx));
        KASSERT(pktc_idx < SGE_NCOUNTERS,       /* -ve is ok, means don't use */
            ("%s: bad pktc_idx %d", __func__, pktc_idx));
        KASSERT(intr_idx >= -1 && intr_idx < sc->intr_count,
            ("%s: bad intr_idx %d", __func__, intr_idx));
        KASSERT(qtype == FW_IQ_IQTYPE_OTHER || qtype == FW_IQ_IQTYPE_NIC ||
            qtype == FW_IQ_IQTYPE_OFLD, ("%s: bad qtype %d", __func__, qtype));

        iq->flags = 0;
        iq->state = IQS_DISABLED;
        iq->adapter = sc;
        iq->qtype = qtype;
        iq->intr_params = V_QINTR_TIMER_IDX(tmr_idx);
        iq->intr_pktc_idx = SGE_NCOUNTERS - 1;
        if (pktc_idx >= 0) {
                iq->intr_params |= F_QINTR_CNT_EN;
                iq->intr_pktc_idx = pktc_idx;
        }
        iq->qsize = roundup2(qsize, 16);        /* See FW_IQ_CMD/iqsize */
        iq->sidx = iq->qsize - sc->params.sge.spg_len / IQ_ESIZE;
        iq->intr_idx = intr_idx;
        iq->cong_drop = cong;
}

static inline void
init_fl(struct adapter *sc, struct sge_fl *fl, int qsize, int maxp, char *name)
{
        struct sge_params *sp = &sc->params.sge;

        fl->qsize = qsize;
        fl->sidx = qsize - sc->params.sge.spg_len / EQ_ESIZE;
        strlcpy(fl->lockname, name, sizeof(fl->lockname));
        mtx_init(&fl->fl_lock, fl->lockname, NULL, MTX_DEF);
        if (sc->flags & BUF_PACKING_OK &&
            ((!is_t4(sc) && buffer_packing) ||  /* T5+: enabled unless 0 */
            (is_t4(sc) && buffer_packing == 1)))/* T4: disabled unless 1 */
                fl->flags |= FL_BUF_PACKING;
        fl->zidx = find_refill_source(sc, maxp, fl->flags & FL_BUF_PACKING);
        fl->safe_zidx = sc->sge.safe_zidx;
        if (fl->flags & FL_BUF_PACKING) {
                fl->lowat = roundup2(sp->fl_starve_threshold2, 8);
                fl->buf_boundary = sp->pack_boundary;
        } else {
                fl->lowat = roundup2(sp->fl_starve_threshold, 8);
                fl->buf_boundary = 16;
        }
        if (fl_pad && fl->buf_boundary < sp->pad_boundary)
                fl->buf_boundary = sp->pad_boundary;
}

static inline void
init_eq(struct adapter *sc, struct sge_eq *eq, int eqtype, int qsize,
    uint8_t port_id, struct sge_iq *iq, char *name)
{
        KASSERT(eqtype >= EQ_CTRL && eqtype <= EQ_OFLD,
            ("%s: bad qtype %d", __func__, eqtype));

        eq->type = eqtype;
        eq->port_id = port_id;
        eq->tx_chan = sc->port[port_id]->tx_chan;
        eq->hw_port = sc->port[port_id]->hw_port;
        eq->iq = iq;
        eq->sidx = qsize - sc->params.sge.spg_len / EQ_ESIZE;
        strlcpy(eq->lockname, name, sizeof(eq->lockname));
        mtx_init(&eq->eq_lock, eq->lockname, NULL, MTX_DEF);
}

int
alloc_ring(struct adapter *sc, size_t len, bus_dma_tag_t *tag,
    bus_dmamap_t *map, bus_addr_t *pa, void **va)
{
        int rc;

        rc = bus_dma_tag_create(sc->dmat, 512, 0, BUS_SPACE_MAXADDR,
            BUS_SPACE_MAXADDR, NULL, NULL, len, 1, len, 0, NULL, NULL, tag);
        if (rc != 0) {
                CH_ERR(sc, "cannot allocate DMA tag: %d\n", rc);
                goto done;
        }

        rc = bus_dmamem_alloc(*tag, va,
            BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO, map);
        if (rc != 0) {
                CH_ERR(sc, "cannot allocate DMA memory: %d\n", rc);
                goto done;
        }

        rc = bus_dmamap_load(*tag, *map, *va, len, oneseg_dma_callback, pa, 0);
        if (rc != 0) {
                CH_ERR(sc, "cannot load DMA map: %d\n", rc);
                goto done;
        }
done:
        if (rc)
                free_ring(sc, *tag, *map, *pa, *va);

        return (rc);
}

int
free_ring(struct adapter *sc, bus_dma_tag_t tag, bus_dmamap_t map,
    bus_addr_t pa, void *va)
{
        if (pa)
                bus_dmamap_unload(tag, map);
        if (va)
                bus_dmamem_free(tag, va, map);
        if (tag)
                bus_dma_tag_destroy(tag);

        return (0);
}

/*
 * Allocates the software resources (mainly memory and sysctl nodes) for an
 * ingress queue and an optional freelist.
 *
 * Sets IQ_SW_ALLOCATED and returns 0 on success.
 */
static int
alloc_iq_fl(struct vi_info *vi, struct sge_iq *iq, struct sge_fl *fl,
    struct sysctl_ctx_list *ctx, struct sysctl_oid *oid)
{
        int rc;
        size_t len;
        struct adapter *sc = vi->adapter;

        MPASS(!(iq->flags & IQ_SW_ALLOCATED));

        len = iq->qsize * IQ_ESIZE;
        rc = alloc_ring(sc, len, &iq->desc_tag, &iq->desc_map, &iq->ba,
            (void **)&iq->desc);
        if (rc != 0)
                return (rc);

        if (fl) {
                len = fl->qsize * EQ_ESIZE;
                rc = alloc_ring(sc, len, &fl->desc_tag, &fl->desc_map,
                    &fl->ba, (void **)&fl->desc);
                if (rc) {
                        free_ring(sc, iq->desc_tag, iq->desc_map, iq->ba,
                            iq->desc);
                        return (rc);
                }

                /* Allocate space for one software descriptor per buffer. */
                fl->sdesc = malloc(fl->sidx * 8 * sizeof(struct fl_sdesc),
                    M_CXGBE, M_ZERO | M_WAITOK);

                add_fl_sysctls(sc, ctx, oid, fl);
                iq->flags |= IQ_HAS_FL;
        }
        add_iq_sysctls(ctx, oid, iq);
        iq->flags |= IQ_SW_ALLOCATED;

        return (0);
}

/*
 * Frees all software resources (memory and locks) associated with an ingress
 * queue and an optional freelist.
 */
static void
free_iq_fl(struct adapter *sc, struct sge_iq *iq, struct sge_fl *fl)
{
        MPASS(iq->flags & IQ_SW_ALLOCATED);

        if (fl) {
                MPASS(iq->flags & IQ_HAS_FL);
                free_ring(sc, fl->desc_tag, fl->desc_map, fl->ba, fl->desc);
                free_fl_buffers(sc, fl);
                free(fl->sdesc, M_CXGBE);
                mtx_destroy(&fl->fl_lock);
                bzero(fl, sizeof(*fl));
        }
        free_ring(sc, iq->desc_tag, iq->desc_map, iq->ba, iq->desc);
        bzero(iq, sizeof(*iq));
}

/*
 * Allocates a hardware ingress queue and an optional freelist that will be
 * associated with it.
 *
 * Returns errno on failure.  Resources allocated up to that point may still be
 * allocated.  Caller is responsible for cleanup in case this function fails.
 */
static int
alloc_iq_fl_hwq(struct vi_info *vi, struct sge_iq *iq, struct sge_fl *fl)
{
        int rc, cntxt_id, cong_map;
        struct fw_iq_cmd c;
        struct adapter *sc = vi->adapter;
        struct port_info *pi = vi->pi;
        __be32 v = 0;

        MPASS (!(iq->flags & IQ_HW_ALLOCATED));

        bzero(&c, sizeof(c));
        c.op_to_vfn = htobe32(V_FW_CMD_OP(FW_IQ_CMD) | F_FW_CMD_REQUEST |
            F_FW_CMD_WRITE | F_FW_CMD_EXEC | V_FW_IQ_CMD_PFN(sc->pf) |
            V_FW_IQ_CMD_VFN(0));

        c.alloc_to_len16 = htobe32(F_FW_IQ_CMD_ALLOC | F_FW_IQ_CMD_IQSTART |
            FW_LEN16(c));

        /* Special handling for firmware event queue */
        if (iq == &sc->sge.fwq)
                v |= F_FW_IQ_CMD_IQASYNCH;

        if (iq->intr_idx < 0) {
                /* Forwarded interrupts, all headed to fwq */
                v |= F_FW_IQ_CMD_IQANDST;
                v |= V_FW_IQ_CMD_IQANDSTINDEX(sc->sge.fwq.cntxt_id);
        } else {
                KASSERT(iq->intr_idx < sc->intr_count,
                    ("%s: invalid direct intr_idx %d", __func__, iq->intr_idx));
                v |= V_FW_IQ_CMD_IQANDSTINDEX(iq->intr_idx);
        }

        bzero(iq->desc, iq->qsize * IQ_ESIZE);
        c.type_to_iqandstindex = htobe32(v |
            V_FW_IQ_CMD_TYPE(FW_IQ_TYPE_FL_INT_CAP) |
            V_FW_IQ_CMD_VIID(vi->viid) |
            V_FW_IQ_CMD_IQANUD(X_UPDATEDELIVERY_INTERRUPT));
        c.iqdroprss_to_iqesize = htobe16(V_FW_IQ_CMD_IQPCIECH(pi->hw_port) |
            F_FW_IQ_CMD_IQGTSMODE |
            V_FW_IQ_CMD_IQINTCNTTHRESH(iq->intr_pktc_idx) |
            V_FW_IQ_CMD_IQESIZE(ilog2(IQ_ESIZE) - 4));
        c.iqsize = htobe16(iq->qsize);
        c.iqaddr = htobe64(iq->ba);
        c.iqns_to_fl0congen = htobe32(V_FW_IQ_CMD_IQTYPE(iq->qtype));
        if (iq->cong_drop != -1) {
                if (iq->qtype == IQ_ETH) {
                        if (chip_id(sc) >= CHELSIO_T7)
                                cong_map = 1 << pi->hw_port;
                        else
                                cong_map = pi->rx_e_chan_map;
                } else
                        cong_map = 0;
                c.iqns_to_fl0congen |= htobe32(F_FW_IQ_CMD_IQFLINTCONGEN);
        }

        if (fl) {
                bzero(fl->desc, fl->sidx * EQ_ESIZE + sc->params.sge.spg_len);
                c.iqns_to_fl0congen |=
                    htobe32(V_FW_IQ_CMD_FL0HOSTFCMODE(X_HOSTFCMODE_NONE) |
                        F_FW_IQ_CMD_FL0FETCHRO | F_FW_IQ_CMD_FL0DATARO |
                        (fl_pad ? F_FW_IQ_CMD_FL0PADEN : 0) |
                        (fl->flags & FL_BUF_PACKING ? F_FW_IQ_CMD_FL0PACKEN :
                            0));
                if (iq->cong_drop != -1) {
                        c.iqns_to_fl0congen |=
                                htobe32(V_FW_IQ_CMD_FL0CNGCHMAP(cong_map) |
                                    F_FW_IQ_CMD_FL0CONGCIF |
                                    F_FW_IQ_CMD_FL0CONGEN);
                }
                c.fl0dcaen_to_fl0cidxfthresh =
                    htobe16(V_FW_IQ_CMD_FL0FBMIN(chip_id(sc) <= CHELSIO_T5 ?
                        X_FETCHBURSTMIN_128B : X_FETCHBURSTMIN_64B_T6) |
                        V_FW_IQ_CMD_FL0FBMAX(chip_id(sc) <= CHELSIO_T5 ?
                        X_FETCHBURSTMAX_512B : X_FETCHBURSTMAX_256B));
                c.fl0size = htobe16(fl->qsize);
                c.fl0addr = htobe64(fl->ba);
        }

        rc = -t4_wr_mbox(sc, sc->mbox, &c, sizeof(c), &c);
        if (rc != 0) {
                CH_ERR(sc, "failed to create hw ingress queue: %d\n", rc);
                return (rc);
        }

        iq->cidx = 0;
        iq->gen = F_RSPD_GEN;
        iq->cntxt_id = be16toh(c.iqid);
        iq->abs_id = be16toh(c.physiqid);

        cntxt_id = iq->cntxt_id - sc->sge.iq_start;
        if (cntxt_id >= sc->sge.iqmap_sz) {
                panic ("%s: iq->cntxt_id (%d) more than the max (%d)", __func__,
                    cntxt_id, sc->sge.iqmap_sz - 1);
        }
        sc->sge.iqmap[cntxt_id] = iq;

        if (fl) {
                u_int qid;
#ifdef INVARIANTS
                int i;

                MPASS(!(fl->flags & FL_BUF_RESUME));
                for (i = 0; i < fl->sidx * 8; i++)
                        MPASS(fl->sdesc[i].cl == NULL);
#endif
                fl->cntxt_id = be16toh(c.fl0id);
                fl->pidx = fl->cidx = fl->hw_cidx = fl->dbidx = 0;
                fl->rx_offset = 0;
                fl->flags &= ~(FL_STARVING | FL_DOOMED);

                cntxt_id = fl->cntxt_id - sc->sge.eq_start;
                if (cntxt_id >= sc->sge.eqmap_sz) {
                        panic("%s: fl->cntxt_id (%d) more than the max (%d)",
                            __func__, cntxt_id, sc->sge.eqmap_sz - 1);
                }
                sc->sge.eqmap[cntxt_id] = (void *)fl;

                qid = fl->cntxt_id;
                if (isset(&sc->doorbells, DOORBELL_UDB)) {
                        uint32_t s_qpp = sc->params.sge.eq_s_qpp;
                        uint32_t mask = (1 << s_qpp) - 1;
                        volatile uint8_t *udb;

                        udb = sc->udbs_base + UDBS_DB_OFFSET;
                        udb += (qid >> s_qpp) << PAGE_SHIFT;
                        qid &= mask;
                        if (qid < PAGE_SIZE / UDBS_SEG_SIZE) {
                                udb += qid << UDBS_SEG_SHIFT;
                                qid = 0;
                        }
                        fl->udb = (volatile void *)udb;
                }
                fl->dbval = V_QID(qid) | sc->chip_params->sge_fl_db;

                FL_LOCK(fl);
                /* Enough to make sure the SGE doesn't think it's starved */
                refill_fl(sc, fl, fl->lowat);
                FL_UNLOCK(fl);
        }

        if (chip_id(sc) >= CHELSIO_T5 && !(sc->flags & IS_VF) &&
            iq->cong_drop != -1) {
                t4_sge_set_conm_context(sc, iq->cntxt_id, iq->cong_drop,
                    cong_map);
        }

        /* Enable IQ interrupts */
        atomic_store_rel_int(&iq->state, IQS_IDLE);
        t4_write_reg(sc, sc->sge_gts_reg, V_SEINTARM(iq->intr_params) |
            V_INGRESSQID(iq->cntxt_id));

        iq->flags |= IQ_HW_ALLOCATED;

        return (0);
}

static int
free_iq_fl_hwq(struct adapter *sc, struct sge_iq *iq, struct sge_fl *fl)
{
        int rc;

        MPASS(iq->flags & IQ_HW_ALLOCATED);
        rc = -t4_iq_free(sc, sc->mbox, sc->pf, 0, FW_IQ_TYPE_FL_INT_CAP,
            iq->cntxt_id, fl ? fl->cntxt_id : 0xffff, 0xffff);
        if (rc != 0) {
                CH_ERR(sc, "failed to free iq %p: %d\n", iq, rc);
                return (rc);
        }
        iq->flags &= ~IQ_HW_ALLOCATED;

        return (0);
}

static void
add_iq_sysctls(struct sysctl_ctx_list *ctx, struct sysctl_oid *oid,
    struct sge_iq *iq)
{
        struct sysctl_oid_list *children;

        if (ctx == NULL || oid == NULL)
                return;

        children = SYSCTL_CHILDREN(oid);
        SYSCTL_ADD_UAUTO(ctx, children, OID_AUTO, "ba", CTLFLAG_RD, &iq->ba,
            "bus address of descriptor ring");
        SYSCTL_ADD_INT(ctx, children, OID_AUTO, "dmalen", CTLFLAG_RD, NULL,
            iq->qsize * IQ_ESIZE, "descriptor ring size in bytes");
        SYSCTL_ADD_U16(ctx, children, OID_AUTO, "abs_id", CTLFLAG_RD,
            &iq->abs_id, 0, "absolute id of the queue");
        SYSCTL_ADD_U16(ctx, children, OID_AUTO, "cntxt_id", CTLFLAG_RD,
            &iq->cntxt_id, 0, "SGE context id of the queue");
        SYSCTL_ADD_U16(ctx, children, OID_AUTO, "cidx", CTLFLAG_RD, &iq->cidx,
            0, "consumer index");
}

static void
add_fl_sysctls(struct adapter *sc, struct sysctl_ctx_list *ctx,
    struct sysctl_oid *oid, struct sge_fl *fl)
{
        struct sysctl_oid_list *children;

        if (ctx == NULL || oid == NULL)
                return;

        children = SYSCTL_CHILDREN(oid);
        oid = SYSCTL_ADD_NODE(ctx, children, OID_AUTO, "fl",
            CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "freelist");
        children = SYSCTL_CHILDREN(oid);

        SYSCTL_ADD_UAUTO(ctx, children, OID_AUTO, "ba", CTLFLAG_RD,
            &fl->ba, "bus address of descriptor ring");
        SYSCTL_ADD_INT(ctx, children, OID_AUTO, "dmalen", CTLFLAG_RD, NULL,
            fl->sidx * EQ_ESIZE + sc->params.sge.spg_len,
            "desc ring size in bytes");
        SYSCTL_ADD_U16(ctx, children, OID_AUTO, "cntxt_id", CTLFLAG_RD,
            &fl->cntxt_id, 0, "SGE context id of the freelist");
        SYSCTL_ADD_UINT(ctx, children, OID_AUTO, "padding", CTLFLAG_RD, NULL,
            fl_pad ? 1 : 0, "padding enabled");
        SYSCTL_ADD_UINT(ctx, children, OID_AUTO, "packing", CTLFLAG_RD, NULL,
            fl->flags & FL_BUF_PACKING ? 1 : 0, "packing enabled");
        SYSCTL_ADD_UINT(ctx, children, OID_AUTO, "cidx", CTLFLAG_RD, &fl->cidx,
            0, "consumer index");
        if (fl->flags & FL_BUF_PACKING) {
                SYSCTL_ADD_UINT(ctx, children, OID_AUTO, "rx_offset",
                    CTLFLAG_RD, &fl->rx_offset, 0, "packing rx offset");
        }
        SYSCTL_ADD_UINT(ctx, children, OID_AUTO, "pidx", CTLFLAG_RD, &fl->pidx,
            0, "producer index");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "cluster_allocated",
            CTLFLAG_RD, &fl->cl_allocated, "# of clusters allocated");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "cluster_recycled",
            CTLFLAG_RD, &fl->cl_recycled, "# of clusters recycled");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "cluster_fast_recycled",
            CTLFLAG_RD, &fl->cl_fast_recycled, "# of clusters recycled (fast)");
}

/*
 * Idempotent.
 */
static int
alloc_fwq(struct adapter *sc)
{
        int rc, intr_idx;
        struct sge_iq *fwq = &sc->sge.fwq;
        struct vi_info *vi = &sc->port[0]->vi[0];

        if (!(fwq->flags & IQ_SW_ALLOCATED)) {
                MPASS(!(fwq->flags & IQ_HW_ALLOCATED));

                if (sc->flags & IS_VF)
                        intr_idx = 0;
                else
                        intr_idx = sc->intr_count > 1 ? 1 : 0;
                init_iq(fwq, sc, 0, 0, FW_IQ_QSIZE, intr_idx, -1, IQ_OTHER);
                rc = alloc_iq_fl(vi, fwq, NULL, &sc->ctx, sc->fwq_oid);
                if (rc != 0) {
                        CH_ERR(sc, "failed to allocate fwq: %d\n", rc);
                        return (rc);
                }
                MPASS(fwq->flags & IQ_SW_ALLOCATED);
        }

        if (!(fwq->flags & IQ_HW_ALLOCATED)) {
                MPASS(fwq->flags & IQ_SW_ALLOCATED);

                rc = alloc_iq_fl_hwq(vi, fwq, NULL);
                if (rc != 0) {
                        CH_ERR(sc, "failed to create hw fwq: %d\n", rc);
                        return (rc);
                }
                MPASS(fwq->flags & IQ_HW_ALLOCATED);
        }

        return (0);
}

/*
 * Idempotent.
 */
static void
free_fwq(struct adapter *sc)
{
        struct sge_iq *fwq = &sc->sge.fwq;

        if (fwq->flags & IQ_HW_ALLOCATED) {
                MPASS(fwq->flags & IQ_SW_ALLOCATED);
                free_iq_fl_hwq(sc, fwq, NULL);
                MPASS(!(fwq->flags & IQ_HW_ALLOCATED));
        }

        if (fwq->flags & IQ_SW_ALLOCATED) {
                MPASS(!(fwq->flags & IQ_HW_ALLOCATED));
                free_iq_fl(sc, fwq, NULL);
                MPASS(!(fwq->flags & IQ_SW_ALLOCATED));
        }
}

/*
 * Idempotent.
 */
static int
alloc_ctrlq(struct adapter *sc, int idx)
{
        int rc;
        char name[16];
        struct sysctl_oid *oid;
        struct sge_wrq *ctrlq = &sc->sge.ctrlq[idx];

        MPASS(idx < sc->sge.nctrlq);

        if (!(ctrlq->eq.flags & EQ_SW_ALLOCATED)) {
                MPASS(!(ctrlq->eq.flags & EQ_HW_ALLOCATED));

                snprintf(name, sizeof(name), "%d", idx);
                oid = SYSCTL_ADD_NODE(&sc->ctx, SYSCTL_CHILDREN(sc->ctrlq_oid),
                    OID_AUTO, name, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
                    "ctrl queue");

                snprintf(name, sizeof(name), "%s ctrlq%d",
                    device_get_nameunit(sc->dev), idx);
                init_eq(sc, &ctrlq->eq, EQ_CTRL, CTRL_EQ_QSIZE,
                    idx % sc->params.nports, &sc->sge.fwq, name);
                rc = alloc_wrq(sc, NULL, ctrlq, &sc->ctx, oid);
                if (rc != 0) {
                        CH_ERR(sc, "failed to allocate ctrlq%d: %d\n", idx, rc);
                        sysctl_remove_oid(oid, 1, 1);
                        return (rc);
                }
                MPASS(ctrlq->eq.flags & EQ_SW_ALLOCATED);
        }

        if (!(ctrlq->eq.flags & EQ_HW_ALLOCATED)) {
                MPASS(ctrlq->eq.flags & EQ_SW_ALLOCATED);
                MPASS(ctrlq->nwr_pending == 0);
                MPASS(ctrlq->ndesc_needed == 0);

                rc = alloc_eq_hwq(sc, NULL, &ctrlq->eq, idx);
                if (rc != 0) {
                        CH_ERR(sc, "failed to create hw ctrlq%d: %d\n", idx, rc);
                        return (rc);
                }
                MPASS(ctrlq->eq.flags & EQ_HW_ALLOCATED);
        }

        return (0);
}

/*
 * Idempotent.
 */
static void
free_ctrlq(struct adapter *sc, int idx)
{
        struct sge_wrq *ctrlq = &sc->sge.ctrlq[idx];

        if (ctrlq->eq.flags & EQ_HW_ALLOCATED) {
                MPASS(ctrlq->eq.flags & EQ_SW_ALLOCATED);
                free_eq_hwq(sc, NULL, &ctrlq->eq);
                MPASS(!(ctrlq->eq.flags & EQ_HW_ALLOCATED));
        }

        if (ctrlq->eq.flags & EQ_SW_ALLOCATED) {
                MPASS(!(ctrlq->eq.flags & EQ_HW_ALLOCATED));
                free_wrq(sc, ctrlq);
                MPASS(!(ctrlq->eq.flags & EQ_SW_ALLOCATED));
        }
}

int
t4_sge_set_conm_context(struct adapter *sc, int cntxt_id, int cong_drop,
    int cong_map)
{
        const int cng_ch_bits_log = sc->chip_params->cng_ch_bits_log;
        uint32_t param, val;
        uint16_t ch_map;
        int cong_mode, rc, i;

        if (chip_id(sc) < CHELSIO_T5)
                return (ENOTSUP);

        /* Convert the driver knob to the mode understood by the firmware. */
        switch (cong_drop) {
        case -1:
                cong_mode = X_CONMCTXT_CNGTPMODE_DISABLE;
                break;
        case 0:
                cong_mode = X_CONMCTXT_CNGTPMODE_CHANNEL;
                break;
        case 1:
                cong_mode = X_CONMCTXT_CNGTPMODE_QUEUE;
                break;
        case 2:
                cong_mode = X_CONMCTXT_CNGTPMODE_BOTH;
                break;
        default:
                MPASS(0);
                CH_ERR(sc, "cong_drop = %d is invalid (ingress queue %d).\n",
                    cong_drop, cntxt_id);
                return (EINVAL);
        }

        param = V_FW_PARAMS_MNEM(FW_PARAMS_MNEM_DMAQ) |
            V_FW_PARAMS_PARAM_X(FW_PARAMS_PARAM_DMAQ_CONM_CTXT) |
            V_FW_PARAMS_PARAM_YZ(cntxt_id);
        if (chip_id(sc) >= CHELSIO_T7) {
                val = V_T7_DMAQ_CONM_CTXT_CNGTPMODE(cong_mode) |
                    V_T7_DMAQ_CONM_CTXT_CH_VEC(cong_map);
        } else {
                val = V_CONMCTXT_CNGTPMODE(cong_mode);
                if (cong_mode == X_CONMCTXT_CNGTPMODE_CHANNEL ||
                    cong_mode == X_CONMCTXT_CNGTPMODE_BOTH) {
                        for (i = 0, ch_map = 0; i < 4; i++) {
                                if (cong_map & (1 << i))
                                        ch_map |= 1 << (i << cng_ch_bits_log);
                        }
                        val |= V_CONMCTXT_CNGCHMAP(ch_map);
                }
        }
        rc = -t4_set_params(sc, sc->mbox, sc->pf, 0, 1, &param, &val);
        if (rc != 0) {
                CH_ERR(sc, "failed to set congestion manager context "
                    "for ingress queue %d: %d\n", cntxt_id, rc);
        }

        return (rc);
}

/*
 * Idempotent.
 */
static int
alloc_rxq(struct vi_info *vi, struct sge_rxq *rxq, int idx, int intr_idx,
    int maxp)
{
        int rc;
        struct adapter *sc = vi->adapter;
        if_t ifp = vi->ifp;
        struct sysctl_oid *oid;
        char name[16];

        if (!(rxq->iq.flags & IQ_SW_ALLOCATED)) {
                MPASS(!(rxq->iq.flags & IQ_HW_ALLOCATED));
#if defined(INET) || defined(INET6)
                rc = tcp_lro_init_args(&rxq->lro, ifp, lro_entries, lro_mbufs);
                if (rc != 0)
                        return (rc);
                MPASS(rxq->lro.ifp == ifp);     /* also indicates LRO init'ed */
#endif
                rxq->ifp = ifp;

                snprintf(name, sizeof(name), "%d", idx);
                oid = SYSCTL_ADD_NODE(&vi->ctx, SYSCTL_CHILDREN(vi->rxq_oid),
                    OID_AUTO, name, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
                    "rx queue");

                init_iq(&rxq->iq, sc, vi->tmr_idx, vi->pktc_idx, vi->qsize_rxq,
                    intr_idx, cong_drop, IQ_ETH);
#if defined(INET) || defined(INET6)
                if (if_getcapenable(ifp) & IFCAP_LRO)
                        rxq->iq.flags |= IQ_LRO_ENABLED;
#endif
                if (if_getcapenable(ifp) & IFCAP_HWRXTSTMP)
                        rxq->iq.flags |= IQ_RX_TIMESTAMP;
                snprintf(name, sizeof(name), "%s rxq%d-fl",
                    device_get_nameunit(vi->dev), idx);
                init_fl(sc, &rxq->fl, vi->qsize_rxq / 8, maxp, name);
                rc = alloc_iq_fl(vi, &rxq->iq, &rxq->fl, &vi->ctx, oid);
                if (rc != 0) {
                        CH_ERR(vi, "failed to allocate rxq%d: %d\n", idx, rc);
                        sysctl_remove_oid(oid, 1, 1);
#if defined(INET) || defined(INET6)
                        tcp_lro_free(&rxq->lro);
                        rxq->lro.ifp = NULL;
#endif
                        return (rc);
                }
                MPASS(rxq->iq.flags & IQ_SW_ALLOCATED);
                add_rxq_sysctls(&vi->ctx, oid, rxq);
        }

        if (!(rxq->iq.flags & IQ_HW_ALLOCATED)) {
                MPASS(rxq->iq.flags & IQ_SW_ALLOCATED);
                rc = alloc_iq_fl_hwq(vi, &rxq->iq, &rxq->fl);
                if (rc != 0) {
                        CH_ERR(vi, "failed to create hw rxq%d: %d\n", idx, rc);
                        return (rc);
                }
                MPASS(rxq->iq.flags & IQ_HW_ALLOCATED);

                if (idx == 0)
                        sc->sge.iq_base = rxq->iq.abs_id - rxq->iq.cntxt_id;
                else
                        KASSERT(rxq->iq.cntxt_id + sc->sge.iq_base == rxq->iq.abs_id,
                            ("iq_base mismatch"));
                KASSERT(sc->sge.iq_base == 0 || sc->flags & IS_VF,
                    ("PF with non-zero iq_base"));

                /*
                 * The freelist is just barely above the starvation threshold
                 * right now, fill it up a bit more.
                 */
                FL_LOCK(&rxq->fl);
                refill_fl(sc, &rxq->fl, 128);
                FL_UNLOCK(&rxq->fl);
        }

        return (0);
}

/*
 * Idempotent.
 */
static void
free_rxq(struct vi_info *vi, struct sge_rxq *rxq)
{
        if (rxq->iq.flags & IQ_HW_ALLOCATED) {
                MPASS(rxq->iq.flags & IQ_SW_ALLOCATED);
                free_iq_fl_hwq(vi->adapter, &rxq->iq, &rxq->fl);
                MPASS(!(rxq->iq.flags & IQ_HW_ALLOCATED));
        }

        if (rxq->iq.flags & IQ_SW_ALLOCATED) {
                MPASS(!(rxq->iq.flags & IQ_HW_ALLOCATED));
#if defined(INET) || defined(INET6)
                tcp_lro_free(&rxq->lro);
#endif
                free_iq_fl(vi->adapter, &rxq->iq, &rxq->fl);
                MPASS(!(rxq->iq.flags & IQ_SW_ALLOCATED));
                bzero(rxq, sizeof(*rxq));
        }
}

static void
add_rxq_sysctls(struct sysctl_ctx_list *ctx, struct sysctl_oid *oid,
    struct sge_rxq *rxq)
{
        struct sysctl_oid_list *children;

        if (ctx == NULL || oid == NULL)
                return;

        children = SYSCTL_CHILDREN(oid);
#if defined(INET) || defined(INET6)
        SYSCTL_ADD_U64(ctx, children, OID_AUTO, "lro_queued", CTLFLAG_RD,
            &rxq->lro.lro_queued, 0, NULL);
        SYSCTL_ADD_U64(ctx, children, OID_AUTO, "lro_flushed", CTLFLAG_RD,
            &rxq->lro.lro_flushed, 0, NULL);
#endif
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "rxcsum", CTLFLAG_RD,
            &rxq->rxcsum, "# of times hardware assisted with checksum");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "vlan_extraction", CTLFLAG_RD,
            &rxq->vlan_extraction, "# of times hardware extracted 802.1Q tag");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "vxlan_rxcsum", CTLFLAG_RD,
            &rxq->vxlan_rxcsum,
            "# of times hardware assisted with inner checksum (VXLAN)");
}

#ifdef TCP_OFFLOAD
/*
 * Idempotent.
 */
static int
alloc_ofld_rxq(struct vi_info *vi, struct sge_ofld_rxq *ofld_rxq, int idx,
    int intr_idx, int maxp)
{
        int rc;
        struct adapter *sc = vi->adapter;
        struct sysctl_oid *oid;
        char name[16];

        if (!(ofld_rxq->iq.flags & IQ_SW_ALLOCATED)) {
                MPASS(!(ofld_rxq->iq.flags & IQ_HW_ALLOCATED));

                snprintf(name, sizeof(name), "%d", idx);
                oid = SYSCTL_ADD_NODE(&vi->ctx,
                    SYSCTL_CHILDREN(vi->ofld_rxq_oid), OID_AUTO, name,
                    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "offload rx queue");

                init_iq(&ofld_rxq->iq, sc, vi->ofld_tmr_idx, vi->ofld_pktc_idx,
                    vi->qsize_rxq, intr_idx, ofld_cong_drop, IQ_OFLD);
                snprintf(name, sizeof(name), "%s ofld_rxq%d-fl",
                    device_get_nameunit(vi->dev), idx);
                init_fl(sc, &ofld_rxq->fl, vi->qsize_rxq / 8, maxp, name);
                rc = alloc_iq_fl(vi, &ofld_rxq->iq, &ofld_rxq->fl, &vi->ctx,
                    oid);
                if (rc != 0) {
                        CH_ERR(vi, "failed to allocate ofld_rxq%d: %d\n", idx,
                            rc);
                        sysctl_remove_oid(oid, 1, 1);
                        return (rc);
                }
                MPASS(ofld_rxq->iq.flags & IQ_SW_ALLOCATED);
                ofld_rxq->rx_iscsi_ddp_setup_ok = counter_u64_alloc(M_WAITOK);
                ofld_rxq->rx_iscsi_ddp_setup_error =
                    counter_u64_alloc(M_WAITOK);
                ofld_rxq->rx_nvme_ddp_setup_ok = counter_u64_alloc(M_WAITOK);
                ofld_rxq->rx_nvme_ddp_setup_no_stag =
                    counter_u64_alloc(M_WAITOK);
                ofld_rxq->rx_nvme_ddp_setup_error =
                    counter_u64_alloc(M_WAITOK);
                ofld_rxq->rx_nvme_ddp_octets = counter_u64_alloc(M_WAITOK);
                ofld_rxq->rx_nvme_ddp_pdus = counter_u64_alloc(M_WAITOK);
                ofld_rxq->rx_nvme_fl_octets = counter_u64_alloc(M_WAITOK);
                ofld_rxq->rx_nvme_fl_pdus = counter_u64_alloc(M_WAITOK);
                ofld_rxq->rx_nvme_invalid_headers = counter_u64_alloc(M_WAITOK);
                ofld_rxq->rx_nvme_header_digest_errors =
                    counter_u64_alloc(M_WAITOK);
                ofld_rxq->rx_nvme_data_digest_errors =
                    counter_u64_alloc(M_WAITOK);
                ofld_rxq->ddp_buffer_alloc = counter_u64_alloc(M_WAITOK);
                ofld_rxq->ddp_buffer_reuse = counter_u64_alloc(M_WAITOK);
                ofld_rxq->ddp_buffer_free = counter_u64_alloc(M_WAITOK);
                add_ofld_rxq_sysctls(&vi->ctx, oid, ofld_rxq);
        }

        if (!(ofld_rxq->iq.flags & IQ_HW_ALLOCATED)) {
                MPASS(ofld_rxq->iq.flags & IQ_SW_ALLOCATED);
                rc = alloc_iq_fl_hwq(vi, &ofld_rxq->iq, &ofld_rxq->fl);
                if (rc != 0) {
                        CH_ERR(vi, "failed to create hw ofld_rxq%d: %d\n", idx,
                            rc);
                        return (rc);
                }
                MPASS(ofld_rxq->iq.flags & IQ_HW_ALLOCATED);
        }
        return (rc);
}

/*
 * Idempotent.
 */
static void
free_ofld_rxq(struct vi_info *vi, struct sge_ofld_rxq *ofld_rxq)
{
        if (ofld_rxq->iq.flags & IQ_HW_ALLOCATED) {
                MPASS(ofld_rxq->iq.flags & IQ_SW_ALLOCATED);
                free_iq_fl_hwq(vi->adapter, &ofld_rxq->iq, &ofld_rxq->fl);
                MPASS(!(ofld_rxq->iq.flags & IQ_HW_ALLOCATED));
        }

        if (ofld_rxq->iq.flags & IQ_SW_ALLOCATED) {
                MPASS(!(ofld_rxq->iq.flags & IQ_HW_ALLOCATED));
                free_iq_fl(vi->adapter, &ofld_rxq->iq, &ofld_rxq->fl);
                MPASS(!(ofld_rxq->iq.flags & IQ_SW_ALLOCATED));
                counter_u64_free(ofld_rxq->rx_iscsi_ddp_setup_ok);
                counter_u64_free(ofld_rxq->rx_iscsi_ddp_setup_error);
                counter_u64_free(ofld_rxq->rx_nvme_ddp_setup_ok);
                counter_u64_free(ofld_rxq->rx_nvme_ddp_setup_no_stag);
                counter_u64_free(ofld_rxq->rx_nvme_ddp_setup_error);
                counter_u64_free(ofld_rxq->rx_nvme_ddp_octets);
                counter_u64_free(ofld_rxq->rx_nvme_ddp_pdus);
                counter_u64_free(ofld_rxq->rx_nvme_fl_octets);
                counter_u64_free(ofld_rxq->rx_nvme_fl_pdus);
                counter_u64_free(ofld_rxq->rx_nvme_invalid_headers);
                counter_u64_free(ofld_rxq->rx_nvme_header_digest_errors);
                counter_u64_free(ofld_rxq->rx_nvme_data_digest_errors);
                counter_u64_free(ofld_rxq->ddp_buffer_alloc);
                counter_u64_free(ofld_rxq->ddp_buffer_reuse);
                counter_u64_free(ofld_rxq->ddp_buffer_free);
                bzero(ofld_rxq, sizeof(*ofld_rxq));
        }
}

static void
add_ofld_rxq_sysctls(struct sysctl_ctx_list *ctx, struct sysctl_oid *oid,
    struct sge_ofld_rxq *ofld_rxq)
{
        struct sysctl_oid_list *children, *top;

        if (ctx == NULL || oid == NULL)
                return;

        top = children = SYSCTL_CHILDREN(oid);
        SYSCTL_ADD_U64(ctx, children, OID_AUTO, "rx_aio_ddp_jobs",
            CTLFLAG_RD, &ofld_rxq->rx_aio_ddp_jobs, 0,
            "# of aio_read(2) jobs completed via DDP");
        SYSCTL_ADD_U64(ctx, children, OID_AUTO, "rx_aio_ddp_octets",
            CTLFLAG_RD, &ofld_rxq->rx_aio_ddp_octets, 0,
            "# of octets placed directly for aio_read(2) jobs");
        SYSCTL_ADD_ULONG(ctx, children, OID_AUTO,
            "rx_toe_tls_records", CTLFLAG_RD, &ofld_rxq->rx_toe_tls_records,
            "# of TOE TLS records received");
        SYSCTL_ADD_ULONG(ctx, children, OID_AUTO,
            "rx_toe_tls_octets", CTLFLAG_RD, &ofld_rxq->rx_toe_tls_octets,
            "# of payload octets in received TOE TLS records");
        SYSCTL_ADD_ULONG(ctx, children, OID_AUTO,
            "rx_toe_ddp_octets", CTLFLAG_RD, &ofld_rxq->rx_toe_ddp_octets,
            "# of payload octets received via TCP DDP");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO,
            "ddp_buffer_alloc", CTLFLAG_RD, &ofld_rxq->ddp_buffer_alloc,
            "# of DDP RCV buffers allocated");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO,
            "ddp_buffer_reuse", CTLFLAG_RD, &ofld_rxq->ddp_buffer_reuse,
            "# of DDP RCV buffers reused");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO,
            "ddp_buffer_free", CTLFLAG_RD, &ofld_rxq->ddp_buffer_free,
            "# of DDP RCV buffers freed");

        oid = SYSCTL_ADD_NODE(ctx, children, OID_AUTO, "iscsi",
            CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "TOE iSCSI statistics");
        children = SYSCTL_CHILDREN(oid);

        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "ddp_setup_ok",
            CTLFLAG_RD, &ofld_rxq->rx_iscsi_ddp_setup_ok,
            "# of times DDP buffer was setup successfully.");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "ddp_setup_error",
            CTLFLAG_RD, &ofld_rxq->rx_iscsi_ddp_setup_error,
            "# of times DDP buffer setup failed.");
        SYSCTL_ADD_U64(ctx, children, OID_AUTO, "ddp_octets",
            CTLFLAG_RD, &ofld_rxq->rx_iscsi_ddp_octets, 0,
            "# of octets placed directly");
        SYSCTL_ADD_U64(ctx, children, OID_AUTO, "ddp_pdus",
            CTLFLAG_RD, &ofld_rxq->rx_iscsi_ddp_pdus, 0,
            "# of PDUs with data placed directly.");
        SYSCTL_ADD_U64(ctx, children, OID_AUTO, "fl_octets",
            CTLFLAG_RD, &ofld_rxq->rx_iscsi_fl_octets, 0,
            "# of data octets delivered in freelist");
        SYSCTL_ADD_U64(ctx, children, OID_AUTO, "fl_pdus",
            CTLFLAG_RD, &ofld_rxq->rx_iscsi_fl_pdus, 0,
            "# of PDUs with data delivered in freelist");
        SYSCTL_ADD_U64(ctx, children, OID_AUTO, "padding_errors",
            CTLFLAG_RD, &ofld_rxq->rx_iscsi_padding_errors, 0,
            "# of PDUs with invalid padding");
        SYSCTL_ADD_U64(ctx, children, OID_AUTO, "header_digest_errors",
            CTLFLAG_RD, &ofld_rxq->rx_iscsi_header_digest_errors, 0,
            "# of PDUs with invalid header digests");
        SYSCTL_ADD_U64(ctx, children, OID_AUTO, "data_digest_errors",
            CTLFLAG_RD, &ofld_rxq->rx_iscsi_data_digest_errors, 0,
            "# of PDUs with invalid data digests");

        oid = SYSCTL_ADD_NODE(ctx, top, OID_AUTO, "nvme",
            CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "TOE NVMe statistics");
        children = SYSCTL_CHILDREN(oid);

        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "ddp_setup_ok",
            CTLFLAG_RD, &ofld_rxq->rx_nvme_ddp_setup_ok,
            "# of times DDP buffer was setup successfully");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "ddp_setup_no_stag",
            CTLFLAG_RD, &ofld_rxq->rx_nvme_ddp_setup_no_stag,
            "# of times STAG was not available for DDP buffer setup");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "ddp_setup_error",
            CTLFLAG_RD, &ofld_rxq->rx_nvme_ddp_setup_error,
            "# of times DDP buffer setup failed");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "ddp_octets",
            CTLFLAG_RD, &ofld_rxq->rx_nvme_ddp_octets,
            "# of octets placed directly");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "ddp_pdus",
            CTLFLAG_RD, &ofld_rxq->rx_nvme_ddp_pdus,
            "# of PDUs with data placed directly");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "fl_octets",
            CTLFLAG_RD, &ofld_rxq->rx_nvme_fl_octets,
            "# of data octets delivered in freelist");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "fl_pdus",
            CTLFLAG_RD, &ofld_rxq->rx_nvme_fl_pdus,
            "# of PDUs with data delivered in freelist");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "invalid_headers",
            CTLFLAG_RD, &ofld_rxq->rx_nvme_invalid_headers,
            "# of PDUs with invalid header field");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "header_digest_errors",
            CTLFLAG_RD, &ofld_rxq->rx_nvme_header_digest_errors,
            "# of PDUs with invalid header digests");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "data_digest_errors",
            CTLFLAG_RD, &ofld_rxq->rx_nvme_data_digest_errors,
            "# of PDUs with invalid data digests");
}
#endif

/*
 * Returns a reasonable automatic cidx flush threshold for a given queue size.
 */
static u_int
qsize_to_fthresh(int qsize)
{
        u_int fthresh;

        fthresh = qsize == 0 ? 0 : order_base_2(qsize);
        if (fthresh > X_CIDXFLUSHTHRESH_128)
                fthresh = X_CIDXFLUSHTHRESH_128;

        return (fthresh);
}

static int
ctrl_eq_alloc(struct adapter *sc, struct sge_eq *eq, int idx)
{
        int rc, cntxt_id;
        struct fw_eq_ctrl_cmd c;
        int qsize = eq->sidx + sc->params.sge.spg_len / EQ_ESIZE;

        bzero(&c, sizeof(c));

        c.op_to_vfn = htobe32(V_FW_CMD_OP(FW_EQ_CTRL_CMD) | F_FW_CMD_REQUEST |
            F_FW_CMD_WRITE | F_FW_CMD_EXEC | V_FW_EQ_CTRL_CMD_PFN(sc->pf) |
            V_FW_EQ_CTRL_CMD_VFN(0));
        c.alloc_to_len16 = htobe32(F_FW_EQ_CTRL_CMD_ALLOC |
            V_FW_EQ_CTRL_CMD_COREGROUP(idx % sc->params.ncores) |
            F_FW_EQ_CTRL_CMD_EQSTART | FW_LEN16(c));
        c.cmpliqid_eqid = htonl(V_FW_EQ_CTRL_CMD_CMPLIQID(eq->iqid));
        c.physeqid_pkd = htobe32(0);
        c.fetchszm_to_iqid =
            htobe32(V_FW_EQ_CTRL_CMD_HOSTFCMODE(X_HOSTFCMODE_STATUS_PAGE) |
                V_FW_EQ_CTRL_CMD_PCIECHN(eq->hw_port) |
                F_FW_EQ_CTRL_CMD_FETCHRO | V_FW_EQ_CTRL_CMD_IQID(eq->iqid));
        c.dcaen_to_eqsize =
            htobe32(V_FW_EQ_CTRL_CMD_FBMIN(chip_id(sc) <= CHELSIO_T5 ?
                X_FETCHBURSTMIN_64B : X_FETCHBURSTMIN_64B_T6) |
                V_FW_EQ_CTRL_CMD_FBMAX(X_FETCHBURSTMAX_512B) |
                V_FW_EQ_CTRL_CMD_CIDXFTHRESH(qsize_to_fthresh(qsize)) |
                V_FW_EQ_CTRL_CMD_EQSIZE(qsize));
        c.eqaddr = htobe64(eq->ba);

        rc = -t4_wr_mbox(sc, sc->mbox, &c, sizeof(c), &c);
        if (rc != 0) {
                CH_ERR(sc, "failed to create hw ctrlq for port %d: %d\n",
                    eq->port_id, rc);
                return (rc);
        }

        eq->cntxt_id = G_FW_EQ_CTRL_CMD_EQID(be32toh(c.cmpliqid_eqid));
        eq->abs_id = G_FW_EQ_CTRL_CMD_PHYSEQID(be32toh(c.physeqid_pkd));
        cntxt_id = eq->cntxt_id - sc->sge.eq_start;
        if (cntxt_id >= sc->sge.eqmap_sz)
            panic("%s: eq->cntxt_id (%d) more than the max (%d)", __func__,
                cntxt_id, sc->sge.eqmap_sz - 1);
        sc->sge.eqmap[cntxt_id] = eq;

        return (rc);
}

static int
eth_eq_alloc(struct adapter *sc, struct vi_info *vi, struct sge_eq *eq, int idx)
{
        int rc, cntxt_id;
        struct fw_eq_eth_cmd c;
        int qsize = eq->sidx + sc->params.sge.spg_len / EQ_ESIZE;

        bzero(&c, sizeof(c));

        c.op_to_vfn = htobe32(V_FW_CMD_OP(FW_EQ_ETH_CMD) | F_FW_CMD_REQUEST |
            F_FW_CMD_WRITE | F_FW_CMD_EXEC | V_FW_EQ_ETH_CMD_PFN(sc->pf) |
            V_FW_EQ_ETH_CMD_VFN(0));
        c.alloc_to_len16 = htobe32(F_FW_EQ_ETH_CMD_ALLOC |
            V_FW_EQ_ETH_CMD_COREGROUP(idx % sc->params.ncores) |
            F_FW_EQ_ETH_CMD_EQSTART | FW_LEN16(c));
        c.autoequiqe_to_viid = htobe32(F_FW_EQ_ETH_CMD_AUTOEQUIQE |
            F_FW_EQ_ETH_CMD_AUTOEQUEQE | V_FW_EQ_ETH_CMD_VIID(vi->viid));
        c.fetchszm_to_iqid =
            htobe32(V_FW_EQ_ETH_CMD_HOSTFCMODE(X_HOSTFCMODE_NONE) |
                V_FW_EQ_ETH_CMD_PCIECHN(eq->hw_port) | F_FW_EQ_ETH_CMD_FETCHRO |
                V_FW_EQ_ETH_CMD_IQID(eq->iqid));
        c.dcaen_to_eqsize =
            htobe32(V_FW_EQ_ETH_CMD_FBMIN(chip_id(sc) <= CHELSIO_T5 ?
                X_FETCHBURSTMIN_64B : X_FETCHBURSTMIN_64B_T6) |
                V_FW_EQ_ETH_CMD_FBMAX(X_FETCHBURSTMAX_512B) |
                V_FW_EQ_ETH_CMD_EQSIZE(qsize));
        c.eqaddr = htobe64(eq->ba);

        rc = -t4_wr_mbox(sc, sc->mbox, &c, sizeof(c), &c);
        if (rc != 0) {
                device_printf(vi->dev,
                    "failed to create Ethernet egress queue: %d\n", rc);
                return (rc);
        }

        eq->cntxt_id = G_FW_EQ_ETH_CMD_EQID(be32toh(c.eqid_pkd));
        eq->abs_id = G_FW_EQ_ETH_CMD_PHYSEQID(be32toh(c.physeqid_pkd));
        cntxt_id = eq->cntxt_id - sc->sge.eq_start;
        if (cntxt_id >= sc->sge.eqmap_sz)
            panic("%s: eq->cntxt_id (%d) more than the max (%d)", __func__,
                cntxt_id, sc->sge.eqmap_sz - 1);
        sc->sge.eqmap[cntxt_id] = eq;

        return (rc);
}

#if defined(TCP_OFFLOAD) || defined(RATELIMIT)
/*
 * ncores       number of uP cores.
 * nq           number of queues for this VI
 * idx          queue index
 */
static inline int
qidx_to_core(int ncores, int nq, int idx)
{
        MPASS(nq % ncores == 0);
        MPASS(idx >= 0 && idx < nq);

        return (idx * ncores / nq);
}

static int
ofld_eq_alloc(struct adapter *sc, struct vi_info *vi, struct sge_eq *eq,
    int idx)
{
        int rc, cntxt_id, core;
        struct fw_eq_ofld_cmd c;
        int qsize = eq->sidx + sc->params.sge.spg_len / EQ_ESIZE;

        if (sc->params.tid_qid_sel_mask != 0)
                core = qidx_to_core(sc->params.ncores, vi->nofldtxq, idx);
        else
                core = 0;

        bzero(&c, sizeof(c));

        c.op_to_vfn = htonl(V_FW_CMD_OP(FW_EQ_OFLD_CMD) | F_FW_CMD_REQUEST |
            F_FW_CMD_WRITE | F_FW_CMD_EXEC | V_FW_EQ_OFLD_CMD_PFN(sc->pf) |
            V_FW_EQ_OFLD_CMD_VFN(0));
        c.alloc_to_len16 = htonl(F_FW_EQ_OFLD_CMD_ALLOC |
            V_FW_EQ_OFLD_CMD_COREGROUP(core) |
            F_FW_EQ_OFLD_CMD_EQSTART | FW_LEN16(c));
        c.fetchszm_to_iqid =
                htonl(V_FW_EQ_OFLD_CMD_HOSTFCMODE(X_HOSTFCMODE_STATUS_PAGE) |
                    V_FW_EQ_OFLD_CMD_PCIECHN(eq->hw_port) |
                    F_FW_EQ_OFLD_CMD_FETCHRO | V_FW_EQ_OFLD_CMD_IQID(eq->iqid));
        c.dcaen_to_eqsize =
            htobe32(V_FW_EQ_OFLD_CMD_FBMIN(chip_id(sc) <= CHELSIO_T5 ?
                X_FETCHBURSTMIN_64B : X_FETCHBURSTMIN_64B_T6) |
                V_FW_EQ_OFLD_CMD_FBMAX(X_FETCHBURSTMAX_512B) |
                V_FW_EQ_OFLD_CMD_CIDXFTHRESH(qsize_to_fthresh(qsize)) |
                V_FW_EQ_OFLD_CMD_EQSIZE(qsize));
        c.eqaddr = htobe64(eq->ba);

        rc = -t4_wr_mbox(sc, sc->mbox, &c, sizeof(c), &c);
        if (rc != 0) {
                device_printf(vi->dev,
                    "failed to create egress queue for TCP offload: %d\n", rc);
                return (rc);
        }

        eq->cntxt_id = G_FW_EQ_OFLD_CMD_EQID(be32toh(c.eqid_pkd));
        eq->abs_id = G_FW_EQ_OFLD_CMD_PHYSEQID(be32toh(c.physeqid_pkd));
        cntxt_id = eq->cntxt_id - sc->sge.eq_start;
        if (cntxt_id >= sc->sge.eqmap_sz)
            panic("%s: eq->cntxt_id (%d) more than the max (%d)", __func__,
                cntxt_id, sc->sge.eqmap_sz - 1);
        sc->sge.eqmap[cntxt_id] = eq;

        return (rc);
}
#endif

/* SW only */
static int
alloc_eq(struct adapter *sc, struct sge_eq *eq, struct sysctl_ctx_list *ctx,
    struct sysctl_oid *oid)
{
        int rc, qsize;
        size_t len;

        MPASS(!(eq->flags & EQ_SW_ALLOCATED));

        qsize = eq->sidx + sc->params.sge.spg_len / EQ_ESIZE;
        len = qsize * EQ_ESIZE;
        rc = alloc_ring(sc, len, &eq->desc_tag, &eq->desc_map, &eq->ba,
            (void **)&eq->desc);
        if (rc)
                return (rc);
        if (ctx != NULL && oid != NULL)
                add_eq_sysctls(sc, ctx, oid, eq);
        eq->flags |= EQ_SW_ALLOCATED;

        return (0);
}

/* SW only */
static void
free_eq(struct adapter *sc, struct sge_eq *eq)
{
        MPASS(eq->flags & EQ_SW_ALLOCATED);
        if (eq->type == EQ_ETH)
                MPASS(eq->pidx == eq->cidx);

        free_ring(sc, eq->desc_tag, eq->desc_map, eq->ba, eq->desc);
        mtx_destroy(&eq->eq_lock);
        bzero(eq, sizeof(*eq));
}

static void
add_eq_sysctls(struct adapter *sc, struct sysctl_ctx_list *ctx,
    struct sysctl_oid *oid, struct sge_eq *eq)
{
        struct sysctl_oid_list *children = SYSCTL_CHILDREN(oid);

        SYSCTL_ADD_UAUTO(ctx, children, OID_AUTO, "ba", CTLFLAG_RD, &eq->ba,
            "bus address of descriptor ring");
        SYSCTL_ADD_INT(ctx, children, OID_AUTO, "dmalen", CTLFLAG_RD, NULL,
            eq->sidx * EQ_ESIZE + sc->params.sge.spg_len,
            "desc ring size in bytes");
        SYSCTL_ADD_UINT(ctx, children, OID_AUTO, "abs_id", CTLFLAG_RD,
            &eq->abs_id, 0, "absolute id of the queue");
        SYSCTL_ADD_UINT(ctx, children, OID_AUTO, "cntxt_id", CTLFLAG_RD,
            &eq->cntxt_id, 0, "SGE context id of the queue");
        SYSCTL_ADD_U16(ctx, children, OID_AUTO, "cidx", CTLFLAG_RD, &eq->cidx,
            0, "consumer index");
        SYSCTL_ADD_U16(ctx, children, OID_AUTO, "pidx", CTLFLAG_RD, &eq->pidx,
            0, "producer index");
        SYSCTL_ADD_INT(ctx, children, OID_AUTO, "sidx", CTLFLAG_RD, NULL,
            eq->sidx, "status page index");
}

static int
alloc_eq_hwq(struct adapter *sc, struct vi_info *vi, struct sge_eq *eq, int idx)
{
        int rc;

        MPASS(!(eq->flags & EQ_HW_ALLOCATED));

        eq->iqid = eq->iq->cntxt_id;
        eq->pidx = eq->cidx = eq->dbidx = 0;
        /* Note that equeqidx is not used with sge_wrq (OFLD/CTRL) queues. */
        eq->equeqidx = 0;
        eq->doorbells = sc->doorbells;
        bzero(eq->desc, eq->sidx * EQ_ESIZE + sc->params.sge.spg_len);

        switch (eq->type) {
        case EQ_CTRL:
                rc = ctrl_eq_alloc(sc, eq, idx);
                break;

        case EQ_ETH:
                rc = eth_eq_alloc(sc, vi, eq, idx);
                break;

#if defined(TCP_OFFLOAD) || defined(RATELIMIT)
        case EQ_OFLD:
                rc = ofld_eq_alloc(sc, vi, eq, idx);
                break;
#endif

        default:
                panic("%s: invalid eq type %d.", __func__, eq->type);
        }
        if (rc != 0) {
                CH_ERR(sc, "failed to allocate egress queue(%d): %d\n",
                    eq->type, rc);
                return (rc);
        }

        if (isset(&eq->doorbells, DOORBELL_UDB) ||
            isset(&eq->doorbells, DOORBELL_UDBWC) ||
            isset(&eq->doorbells, DOORBELL_WCWR)) {
                uint32_t s_qpp = sc->params.sge.eq_s_qpp;
                uint32_t mask = (1 << s_qpp) - 1;
                volatile uint8_t *udb;

                udb = sc->udbs_base + UDBS_DB_OFFSET;
                udb += (eq->cntxt_id >> s_qpp) << PAGE_SHIFT;   /* pg offset */
                eq->udb_qid = eq->cntxt_id & mask;              /* id in page */
                if (eq->udb_qid >= PAGE_SIZE / UDBS_SEG_SIZE)
                        clrbit(&eq->doorbells, DOORBELL_WCWR);
                else {
                        udb += eq->udb_qid << UDBS_SEG_SHIFT;   /* seg offset */
                        eq->udb_qid = 0;
                }
                eq->udb = (volatile void *)udb;
        }

        eq->flags |= EQ_HW_ALLOCATED;
        return (0);
}

static int
free_eq_hwq(struct adapter *sc, struct vi_info *vi __unused, struct sge_eq *eq)
{
        int rc;

        MPASS(eq->flags & EQ_HW_ALLOCATED);

        switch (eq->type) {
        case EQ_CTRL:
                rc = -t4_ctrl_eq_free(sc, sc->mbox, sc->pf, 0, eq->cntxt_id);
                break;
        case EQ_ETH:
                rc = -t4_eth_eq_free(sc, sc->mbox, sc->pf, 0, eq->cntxt_id);
                break;
#if defined(TCP_OFFLOAD) || defined(RATELIMIT)
        case EQ_OFLD:
                rc = -t4_ofld_eq_free(sc, sc->mbox, sc->pf, 0, eq->cntxt_id);
                break;
#endif
        default:
                panic("%s: invalid eq type %d.", __func__, eq->type);
        }
        if (rc != 0) {
                CH_ERR(sc, "failed to free eq (type %d): %d\n", eq->type, rc);
                return (rc);
        }
        eq->flags &= ~EQ_HW_ALLOCATED;

        return (0);
}

static int
alloc_wrq(struct adapter *sc, struct vi_info *vi, struct sge_wrq *wrq,
    struct sysctl_ctx_list *ctx, struct sysctl_oid *oid)
{
        struct sge_eq *eq = &wrq->eq;
        int rc;

        MPASS(!(eq->flags & EQ_SW_ALLOCATED));

        rc = alloc_eq(sc, eq, ctx, oid);
        if (rc)
                return (rc);
        MPASS(eq->flags & EQ_SW_ALLOCATED);
        /* Can't fail after this. */

        wrq->adapter = sc;
        TASK_INIT(&wrq->wrq_tx_task, 0, wrq_tx_drain, wrq);
        TAILQ_INIT(&wrq->incomplete_wrs);
        STAILQ_INIT(&wrq->wr_list);
        wrq->nwr_pending = 0;
        wrq->ndesc_needed = 0;
        add_wrq_sysctls(ctx, oid, wrq);

        return (0);
}

static void
free_wrq(struct adapter *sc, struct sge_wrq *wrq)
{
        free_eq(sc, &wrq->eq);
        MPASS(wrq->nwr_pending == 0);
        MPASS(wrq->ndesc_needed == 0);
        MPASS(TAILQ_EMPTY(&wrq->incomplete_wrs));
        MPASS(STAILQ_EMPTY(&wrq->wr_list));
        bzero(wrq, sizeof(*wrq));
}

static void
add_wrq_sysctls(struct sysctl_ctx_list *ctx, struct sysctl_oid *oid,
    struct sge_wrq *wrq)
{
        struct sysctl_oid_list *children;

        if (ctx == NULL || oid == NULL)
                return;

        children = SYSCTL_CHILDREN(oid);
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "tx_wrs_direct", CTLFLAG_RD,
            &wrq->tx_wrs_direct, "# of work requests (direct)");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "tx_wrs_copied", CTLFLAG_RD,
            &wrq->tx_wrs_copied, "# of work requests (copied)");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "tx_wrs_sspace", CTLFLAG_RD,
            &wrq->tx_wrs_ss, "# of work requests (copied from scratch space)");
}

/*
 * Idempotent.
 */
static int
alloc_txq(struct vi_info *vi, struct sge_txq *txq, int idx)
{
        int rc, iqidx;
        struct port_info *pi = vi->pi;
        struct adapter *sc = vi->adapter;
        struct sge_eq *eq = &txq->eq;
        struct txpkts *txp;
        char name[16];
        struct sysctl_oid *oid;

        if (!(eq->flags & EQ_SW_ALLOCATED)) {
                MPASS(!(eq->flags & EQ_HW_ALLOCATED));

                snprintf(name, sizeof(name), "%d", idx);
                oid = SYSCTL_ADD_NODE(&vi->ctx, SYSCTL_CHILDREN(vi->txq_oid),
                    OID_AUTO, name, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
                    "tx queue");

                iqidx = vi->first_rxq + (idx % vi->nrxq);
                snprintf(name, sizeof(name), "%s txq%d",
                    device_get_nameunit(vi->dev), idx);
                init_eq(sc, &txq->eq, EQ_ETH, vi->qsize_txq, pi->port_id,
                    &sc->sge.rxq[iqidx].iq, name);

                rc = mp_ring_alloc(&txq->r, eq->sidx, txq, eth_tx,
                    can_resume_eth_tx, M_CXGBE, &eq->eq_lock, M_WAITOK);
                if (rc != 0) {
                        CH_ERR(vi, "failed to allocate mp_ring for txq%d: %d\n",
                            idx, rc);
failed:
                        sysctl_remove_oid(oid, 1, 1);
                        return (rc);
                }

                rc = alloc_eq(sc, eq, &vi->ctx, oid);
                if (rc) {
                        CH_ERR(vi, "failed to allocate txq%d: %d\n", idx, rc);
                        mp_ring_free(txq->r);
                        goto failed;
                }
                MPASS(eq->flags & EQ_SW_ALLOCATED);
                /* Can't fail after this point. */

                TASK_INIT(&txq->tx_reclaim_task, 0, tx_reclaim, eq);
                txq->ifp = vi->ifp;
                txq->gl = sglist_alloc(TX_SGL_SEGS, M_WAITOK);
                txq->sdesc = malloc(eq->sidx * sizeof(struct tx_sdesc), M_CXGBE,
                    M_ZERO | M_WAITOK);

                add_txq_sysctls(vi, &vi->ctx, oid, txq);
        }

        if (!(eq->flags & EQ_HW_ALLOCATED)) {
                MPASS(eq->flags & EQ_SW_ALLOCATED);
                rc = alloc_eq_hwq(sc, vi, eq, idx);
                if (rc != 0) {
                        CH_ERR(vi, "failed to create hw txq%d: %d\n", idx, rc);
                        return (rc);
                }
                MPASS(eq->flags & EQ_HW_ALLOCATED);
                /* Can't fail after this point. */

                if (idx == 0)
                        sc->sge.eq_base = eq->abs_id - eq->cntxt_id;
                else
                        KASSERT(eq->cntxt_id + sc->sge.eq_base == eq->abs_id,
                            ("eq_base mismatch"));
                KASSERT(sc->sge.eq_base == 0 || sc->flags & IS_VF,
                    ("PF with non-zero eq_base"));

                txp = &txq->txp;
                MPASS(nitems(txp->mb) >= sc->params.max_pkts_per_eth_tx_pkts_wr);
                txq->txp.max_npkt = min(nitems(txp->mb),
                    sc->params.max_pkts_per_eth_tx_pkts_wr);
                if (vi->flags & TX_USES_VM_WR && !(sc->flags & IS_VF))
                        txq->txp.max_npkt--;

                if (vi->flags & TX_USES_VM_WR)
                        txq->cpl_ctrl0 = htobe32(V_TXPKT_OPCODE(CPL_TX_PKT_XT) |
                            V_TXPKT_INTF(pi->hw_port));
                else
                        txq->cpl_ctrl0 = htobe32(V_TXPKT_OPCODE(CPL_TX_PKT_XT) |
                            V_TXPKT_INTF(pi->hw_port) | V_TXPKT_PF(sc->pf) |
                            V_TXPKT_VF(vi->vin) | V_TXPKT_VF_VLD(vi->vfvld));

                txq->tc_idx = -1;
        }

        return (0);
}

/*
 * Idempotent.
 */
static void
free_txq(struct vi_info *vi, struct sge_txq *txq)
{
        struct adapter *sc = vi->adapter;
        struct sge_eq *eq = &txq->eq;

        if (eq->flags & EQ_HW_ALLOCATED) {
                MPASS(eq->flags & EQ_SW_ALLOCATED);
                free_eq_hwq(sc, NULL, eq);
                MPASS(!(eq->flags & EQ_HW_ALLOCATED));
        }

        if (eq->flags & EQ_SW_ALLOCATED) {
                MPASS(!(eq->flags & EQ_HW_ALLOCATED));
                sglist_free(txq->gl);
                free(txq->sdesc, M_CXGBE);
                mp_ring_free(txq->r);
                free_eq(sc, eq);
                MPASS(!(eq->flags & EQ_SW_ALLOCATED));
                bzero(txq, sizeof(*txq));
        }
}

static void
add_txq_sysctls(struct vi_info *vi, struct sysctl_ctx_list *ctx,
    struct sysctl_oid *oid, struct sge_txq *txq)
{
        struct adapter *sc;
        struct sysctl_oid_list *children;

        if (ctx == NULL || oid == NULL)
                return;

        sc = vi->adapter;
        children = SYSCTL_CHILDREN(oid);

        mp_ring_sysctls(txq->r, ctx, children);

        SYSCTL_ADD_PROC(ctx, children, OID_AUTO, "tc",
            CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, vi, txq - sc->sge.txq,
            sysctl_tc, "I", "traffic class (-1 means none)");

        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "txcsum", CTLFLAG_RD,
            &txq->txcsum, "# of times hardware assisted with checksum");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "vlan_insertion", CTLFLAG_RD,
            &txq->vlan_insertion, "# of times hardware inserted 802.1Q tag");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "tso_wrs", CTLFLAG_RD,
            &txq->tso_wrs, "# of TSO work requests");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "imm_wrs", CTLFLAG_RD,
            &txq->imm_wrs, "# of work requests with immediate data");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "sgl_wrs", CTLFLAG_RD,
            &txq->sgl_wrs, "# of work requests with direct SGL");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "txpkt_wrs", CTLFLAG_RD,
            &txq->txpkt_wrs, "# of txpkt work requests (one pkt/WR)");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "txpkts0_wrs", CTLFLAG_RD,
            &txq->txpkts0_wrs, "# of txpkts (type 0) work requests");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "txpkts1_wrs", CTLFLAG_RD,
            &txq->txpkts1_wrs, "# of txpkts (type 1) work requests");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "txpkts0_pkts", CTLFLAG_RD,
            &txq->txpkts0_pkts,
            "# of frames tx'd using type0 txpkts work requests");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "txpkts1_pkts", CTLFLAG_RD,
            &txq->txpkts1_pkts,
            "# of frames tx'd using type1 txpkts work requests");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "txpkts_flush", CTLFLAG_RD,
            &txq->txpkts_flush,
            "# of times txpkts had to be flushed out by an egress-update");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "raw_wrs", CTLFLAG_RD,
            &txq->raw_wrs, "# of raw work requests (non-packets)");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "vxlan_tso_wrs", CTLFLAG_RD,
            &txq->vxlan_tso_wrs, "# of VXLAN TSO work requests");
        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "vxlan_txcsum", CTLFLAG_RD,
            &txq->vxlan_txcsum,
            "# of times hardware assisted with inner checksums (VXLAN)");

#ifdef KERN_TLS
        if (is_ktls(sc)) {
                SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "kern_tls_records",
                    CTLFLAG_RD, &txq->kern_tls_records,
                    "# of NIC TLS records transmitted");
                SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "kern_tls_short",
                    CTLFLAG_RD, &txq->kern_tls_short,
                    "# of short NIC TLS records transmitted");
                SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "kern_tls_partial",
                    CTLFLAG_RD, &txq->kern_tls_partial,
                    "# of partial NIC TLS records transmitted");
                SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "kern_tls_full",
                    CTLFLAG_RD, &txq->kern_tls_full,
                    "# of full NIC TLS records transmitted");
                SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "kern_tls_octets",
                    CTLFLAG_RD, &txq->kern_tls_octets,
                    "# of payload octets in transmitted NIC TLS records");
                SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "kern_tls_waste",
                    CTLFLAG_RD, &txq->kern_tls_waste,
                    "# of octets DMAd but not transmitted in NIC TLS records");
                SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "kern_tls_header",
                    CTLFLAG_RD, &txq->kern_tls_header,
                    "# of NIC TLS header-only packets transmitted");
                SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "kern_tls_fin_short",
                    CTLFLAG_RD, &txq->kern_tls_fin_short,
                    "# of NIC TLS padded FIN packets on short TLS records");
                if (is_t6(sc)) {
                        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO,
                            "kern_tls_options", CTLFLAG_RD,
                            &txq->kern_tls_options,
                            "# of NIC TLS options-only packets transmitted");
                        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO,
                            "kern_tls_fin", CTLFLAG_RD, &txq->kern_tls_fin,
                            "# of NIC TLS FIN-only packets transmitted");
                } else {
                        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO,
                            "kern_tls_ghash_received", CTLFLAG_RD,
                            &txq->kern_tls_ghash_received,
                            "# of NIC TLS GHASHes received");
                        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO,
                            "kern_tls_ghash_requested", CTLFLAG_RD,
                            &txq->kern_tls_ghash_requested,
                            "# of NIC TLS GHASHes requested");
                        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO,
                            "kern_tls_lso", CTLFLAG_RD,
                            &txq->kern_tls_lso,
                            "# of NIC TLS records transmitted using LSO");
                        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO,
                            "kern_tls_partial_ghash", CTLFLAG_RD,
                            &txq->kern_tls_partial_ghash,
                            "# of NIC TLS records encrypted using a partial GHASH");
                        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO,
                            "kern_tls_splitmode", CTLFLAG_RD,
                            &txq->kern_tls_splitmode,
                            "# of NIC TLS records using SplitMode");
                        SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO,
                            "kern_tls_trailer", CTLFLAG_RD,
                            &txq->kern_tls_trailer,
                            "# of NIC TLS trailer-only packets transmitted");
                }
                SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "kern_tls_cbc",
                    CTLFLAG_RD, &txq->kern_tls_cbc,
                    "# of NIC TLS sessions using AES-CBC");
                SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "kern_tls_gcm",
                    CTLFLAG_RD, &txq->kern_tls_gcm,
                    "# of NIC TLS sessions using AES-GCM");
        }
#endif
}

#if defined(TCP_OFFLOAD) || defined(RATELIMIT)
/*
 * Idempotent.
 */
static int
alloc_ofld_txq(struct vi_info *vi, struct sge_ofld_txq *ofld_txq, int idx)
{
        struct sysctl_oid *oid;
        struct port_info *pi = vi->pi;
        struct adapter *sc = vi->adapter;
        struct sge_eq *eq = &ofld_txq->wrq.eq;
        int rc, iqidx;
        char name[16];

        MPASS(idx >= 0);
        MPASS(idx < vi->nofldtxq);

        if (!(eq->flags & EQ_SW_ALLOCATED)) {
                snprintf(name, sizeof(name), "%d", idx);
                oid = SYSCTL_ADD_NODE(&vi->ctx,
                    SYSCTL_CHILDREN(vi->ofld_txq_oid), OID_AUTO, name,
                    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "offload tx queue");

                snprintf(name, sizeof(name), "%s ofld_txq%d",
                    device_get_nameunit(vi->dev), idx);
                if (vi->nofldrxq > 0) {
                        iqidx = vi->first_ofld_rxq + (idx % vi->nofldrxq);
                        init_eq(sc, eq, EQ_OFLD, vi->qsize_txq, pi->port_id,
                            &sc->sge.ofld_rxq[iqidx].iq, name);
                } else {
                        iqidx = vi->first_rxq + (idx % vi->nrxq);
                        init_eq(sc, eq, EQ_OFLD, vi->qsize_txq, pi->port_id,
                            &sc->sge.rxq[iqidx].iq, name);
                }

                rc = alloc_wrq(sc, vi, &ofld_txq->wrq, &vi->ctx, oid);
                if (rc != 0) {
                        CH_ERR(vi, "failed to allocate ofld_txq%d: %d\n", idx,
                            rc);
                        sysctl_remove_oid(oid, 1, 1);
                        return (rc);
                }
                MPASS(eq->flags & EQ_SW_ALLOCATED);
                /* Can't fail after this point. */

                ofld_txq->tx_iscsi_pdus = counter_u64_alloc(M_WAITOK);
                ofld_txq->tx_iscsi_octets = counter_u64_alloc(M_WAITOK);
                ofld_txq->tx_iscsi_iso_wrs = counter_u64_alloc(M_WAITOK);
                ofld_txq->tx_nvme_pdus = counter_u64_alloc(M_WAITOK);
                ofld_txq->tx_nvme_octets = counter_u64_alloc(M_WAITOK);
                ofld_txq->tx_nvme_iso_wrs = counter_u64_alloc(M_WAITOK);
                ofld_txq->tx_aio_jobs = counter_u64_alloc(M_WAITOK);
                ofld_txq->tx_aio_octets = counter_u64_alloc(M_WAITOK);
                ofld_txq->tx_toe_tls_records = counter_u64_alloc(M_WAITOK);
                ofld_txq->tx_toe_tls_octets = counter_u64_alloc(M_WAITOK);
                add_ofld_txq_sysctls(&vi->ctx, oid, ofld_txq);
        }

        if (!(eq->flags & EQ_HW_ALLOCATED)) {
                MPASS(eq->flags & EQ_SW_ALLOCATED);
                MPASS(ofld_txq->wrq.nwr_pending == 0);
                MPASS(ofld_txq->wrq.ndesc_needed == 0);
                rc = alloc_eq_hwq(sc, vi, eq, idx);
                if (rc != 0) {
                        CH_ERR(vi, "failed to create hw ofld_txq%d: %d\n", idx,
                            rc);
                        return (rc);
                }
                MPASS(eq->flags & EQ_HW_ALLOCATED);
        }

        return (0);
}

/*
 * Idempotent.
 */
static void
free_ofld_txq(struct vi_info *vi, struct sge_ofld_txq *ofld_txq)
{
        struct adapter *sc = vi->adapter;
        struct sge_eq *eq = &ofld_txq->wrq.eq;

        if (eq->flags & EQ_HW_ALLOCATED) {
                MPASS(eq->flags & EQ_SW_ALLOCATED);
                free_eq_hwq(sc, NULL, eq);
                MPASS(!(eq->flags & EQ_HW_ALLOCATED));
        }

        if (eq->flags & EQ_SW_ALLOCATED) {
                MPASS(!(eq->flags & EQ_HW_ALLOCATED));
                counter_u64_free(ofld_txq->tx_iscsi_pdus);
                counter_u64_free(ofld_txq->tx_iscsi_octets);
                counter_u64_free(ofld_txq->tx_iscsi_iso_wrs);
                counter_u64_free(ofld_txq->tx_nvme_pdus);
                counter_u64_free(ofld_txq->tx_nvme_octets);
                counter_u64_free(ofld_txq->tx_nvme_iso_wrs);
                counter_u64_free(ofld_txq->tx_aio_jobs);
                counter_u64_free(ofld_txq->tx_aio_octets);
                counter_u64_free(ofld_txq->tx_toe_tls_records);
                counter_u64_free(ofld_txq->tx_toe_tls_octets);
                free_wrq(sc, &ofld_txq->wrq);
                MPASS(!(eq->flags & EQ_SW_ALLOCATED));
                bzero(ofld_txq, sizeof(*ofld_txq));
        }
}

static void
add_ofld_txq_sysctls(struct sysctl_ctx_list *ctx, struct sysctl_oid *oid,
    struct sge_ofld_txq *ofld_txq)
{
        struct sysctl_oid_list *children;

        if (ctx == NULL || oid == NULL)
                return;

        children = SYSCTL_CHILDREN(oid);
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "tx_iscsi_pdus",
            CTLFLAG_RD, &ofld_txq->tx_iscsi_pdus,
            "# of iSCSI PDUs transmitted");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "tx_iscsi_octets",
            CTLFLAG_RD, &ofld_txq->tx_iscsi_octets,
            "# of payload octets in transmitted iSCSI PDUs");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "tx_iscsi_iso_wrs",
            CTLFLAG_RD, &ofld_txq->tx_iscsi_iso_wrs,
            "# of iSCSI segmentation offload work requests");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "tx_nvme_pdus",
            CTLFLAG_RD, &ofld_txq->tx_nvme_pdus,
            "# of NVMe PDUs transmitted");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "tx_nvme_octets",
            CTLFLAG_RD, &ofld_txq->tx_nvme_octets,
            "# of payload octets in transmitted NVMe PDUs");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "tx_nvme_iso_wrs",
            CTLFLAG_RD, &ofld_txq->tx_nvme_iso_wrs,
            "# of NVMe segmentation offload work requests");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "tx_aio_jobs",
            CTLFLAG_RD, &ofld_txq->tx_aio_jobs,
            "# of zero-copy aio_write(2) jobs transmitted");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "tx_aio_octets",
            CTLFLAG_RD, &ofld_txq->tx_aio_octets,
            "# of payload octets in transmitted zero-copy aio_write(2) jobs");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "tx_toe_tls_records",
            CTLFLAG_RD, &ofld_txq->tx_toe_tls_records,
            "# of TOE TLS records transmitted");
        SYSCTL_ADD_COUNTER_U64(ctx, children, OID_AUTO, "tx_toe_tls_octets",
            CTLFLAG_RD, &ofld_txq->tx_toe_tls_octets,
            "# of payload octets in transmitted TOE TLS records");
}
#endif

static void
oneseg_dma_callback(void *arg, bus_dma_segment_t *segs, int nseg, int error)
{
        bus_addr_t *ba = arg;

        KASSERT(nseg == 1,
            ("%s meant for single segment mappings only.", __func__));

        *ba = error ? 0 : segs->ds_addr;
}

static inline void
ring_fl_db(struct adapter *sc, struct sge_fl *fl)
{
        uint32_t n, v;

        n = IDXDIFF(fl->pidx >> 3, fl->dbidx, fl->sidx);
        MPASS(n > 0);

        wmb();
        v = fl->dbval | V_PIDX(n);
        if (fl->udb)
                *fl->udb = htole32(v);
        else
                t4_write_reg(sc, sc->sge_kdoorbell_reg, v);
        IDXINCR(fl->dbidx, n, fl->sidx);
}

/*
 * Fills up the freelist by allocating up to 'n' buffers.  Buffers that are
 * recycled do not count towards this allocation budget.
 *
 * Returns non-zero to indicate that this freelist should be added to the list
 * of starving freelists.
 */
static int
refill_fl(struct adapter *sc, struct sge_fl *fl, int n)
{
        __be64 *d;
        struct fl_sdesc *sd;
        uintptr_t pa;
        caddr_t cl;
        struct rx_buf_info *rxb;
        struct cluster_metadata *clm;
        uint16_t max_pidx, zidx = fl->zidx;
        uint16_t hw_cidx = fl->hw_cidx;         /* stable snapshot */

        FL_LOCK_ASSERT_OWNED(fl);

        /*
         * We always stop at the beginning of the hardware descriptor that's just
         * before the one with the hw cidx.  This is to avoid hw pidx = hw cidx,
         * which would mean an empty freelist to the chip.
         */
        max_pidx = __predict_false(hw_cidx == 0) ? fl->sidx - 1 : hw_cidx - 1;
        if (fl->pidx == max_pidx * 8)
                return (0);

        d = &fl->desc[fl->pidx];
        sd = &fl->sdesc[fl->pidx];
        rxb = &sc->sge.rx_buf_info[zidx];

        while (n > 0) {

                if (sd->cl != NULL) {

                        if (sd->nmbuf == 0) {
                                /*
                                 * Fast recycle without involving any atomics on
                                 * the cluster's metadata (if the cluster has
                                 * metadata).  This happens when all frames
                                 * received in the cluster were small enough to
                                 * fit within a single mbuf each.
                                 */
                                fl->cl_fast_recycled++;
                                goto recycled;
                        }

                        /*
                         * Cluster is guaranteed to have metadata.  Clusters
                         * without metadata always take the fast recycle path
                         * when they're recycled.
                         */
                        clm = cl_metadata(sd);
                        MPASS(clm != NULL);

                        if (atomic_fetchadd_int(&clm->refcount, -1) == 1) {
                                fl->cl_recycled++;
                                counter_u64_add(extfree_rels, 1);
                                goto recycled;
                        }
                        sd->cl = NULL;  /* gave up my reference */
                }
                MPASS(sd->cl == NULL);
                cl = uma_zalloc(rxb->zone, M_NOWAIT);
                if (__predict_false(cl == NULL)) {
                        if (zidx != fl->safe_zidx) {
                                zidx = fl->safe_zidx;
                                rxb = &sc->sge.rx_buf_info[zidx];
                                cl = uma_zalloc(rxb->zone, M_NOWAIT);
                        }
                        if (cl == NULL)
                                break;
                }
                fl->cl_allocated++;
                n--;

                pa = pmap_kextract((vm_offset_t)cl);
                sd->cl = cl;
                sd->zidx = zidx;

                if (fl->flags & FL_BUF_PACKING) {
                        *d = htobe64(pa | rxb->hwidx2);
                        sd->moff = rxb->size2;
                } else {
                        *d = htobe64(pa | rxb->hwidx1);
                        sd->moff = 0;
                }
recycled:
                sd->nmbuf = 0;
                d++;
                sd++;
                if (__predict_false((++fl->pidx & 7) == 0)) {
                        uint16_t pidx = fl->pidx >> 3;

                        if (__predict_false(pidx == fl->sidx)) {
                                fl->pidx = 0;
                                pidx = 0;
                                sd = fl->sdesc;
                                d = fl->desc;
                        }
                        if (n < 8 || pidx == max_pidx)
                                break;

                        if (IDXDIFF(pidx, fl->dbidx, fl->sidx) >= 4)
                                ring_fl_db(sc, fl);
                }
        }

        if ((fl->pidx >> 3) != fl->dbidx)
                ring_fl_db(sc, fl);

        return (FL_RUNNING_LOW(fl) && !(fl->flags & FL_STARVING));
}

/*
 * Attempt to refill all starving freelists.
 */
static void
refill_sfl(void *arg)
{
        struct adapter *sc = arg;
        struct sge_fl *fl, *fl_temp;

        mtx_assert(&sc->sfl_lock, MA_OWNED);
        TAILQ_FOREACH_SAFE(fl, &sc->sfl, link, fl_temp) {
                FL_LOCK(fl);
                refill_fl(sc, fl, 64);
                if (FL_NOT_RUNNING_LOW(fl) || fl->flags & FL_DOOMED) {
                        TAILQ_REMOVE(&sc->sfl, fl, link);
                        fl->flags &= ~FL_STARVING;
                }
                FL_UNLOCK(fl);
        }

        if (!TAILQ_EMPTY(&sc->sfl))
                callout_schedule(&sc->sfl_callout, hz / 5);
}

/*
 * Release the driver's reference on all buffers in the given freelist.  Buffers
 * with kernel references cannot be freed and will prevent the driver from being
 * unloaded safely.
 */
void
free_fl_buffers(struct adapter *sc, struct sge_fl *fl)
{
        struct fl_sdesc *sd;
        struct cluster_metadata *clm;
        int i;

        sd = fl->sdesc;
        for (i = 0; i < fl->sidx * 8; i++, sd++) {
                if (sd->cl == NULL)
                        continue;

                if (sd->nmbuf == 0)
                        uma_zfree(sc->sge.rx_buf_info[sd->zidx].zone, sd->cl);
                else if (fl->flags & FL_BUF_PACKING) {
                        clm = cl_metadata(sd);
                        if (atomic_fetchadd_int(&clm->refcount, -1) == 1) {
                                uma_zfree(sc->sge.rx_buf_info[sd->zidx].zone,
                                    sd->cl);
                                counter_u64_add(extfree_rels, 1);
                        }
                }
                sd->cl = NULL;
        }

        if (fl->flags & FL_BUF_RESUME) {
                m_freem(fl->m0);
                fl->flags &= ~FL_BUF_RESUME;
        }
}

static inline void
get_pkt_gl(struct mbuf *m, struct sglist *gl)
{
        int rc;

        M_ASSERTPKTHDR(m);

        sglist_reset(gl);
        rc = sglist_append_mbuf(gl, m);
        if (__predict_false(rc != 0)) {
                panic("%s: mbuf %p (%d segs) was vetted earlier but now fails "
                    "with %d.", __func__, m, mbuf_nsegs(m), rc);
        }

        KASSERT(gl->sg_nseg == mbuf_nsegs(m),
            ("%s: nsegs changed for mbuf %p from %d to %d", __func__, m,
            mbuf_nsegs(m), gl->sg_nseg));
#if 0   /* vm_wr not readily available here. */
        KASSERT(gl->sg_nseg > 0 && gl->sg_nseg <= max_nsegs_allowed(m, vm_wr),
            ("%s: %d segments, should have been 1 <= nsegs <= %d", __func__,
                gl->sg_nseg, max_nsegs_allowed(m, vm_wr)));
#endif
}

/*
 * len16 for a txpkt WR with a GL.  Includes the firmware work request header.
 */
static inline u_int
txpkt_len16(u_int nsegs, const u_int extra)
{
        u_int n;

        MPASS(nsegs > 0);

        nsegs--; /* first segment is part of ulptx_sgl */
        n = extra + sizeof(struct fw_eth_tx_pkt_wr) +
            sizeof(struct cpl_tx_pkt_core) +
            sizeof(struct ulptx_sgl) + 8 * ((3 * nsegs) / 2 + (nsegs & 1));

        return (howmany(n, 16));
}

/*
 * len16 for a txpkt_vm WR with a GL.  Includes the firmware work
 * request header.
 */
static inline u_int
txpkt_vm_len16(u_int nsegs, const u_int extra)
{
        u_int n;

        MPASS(nsegs > 0);

        nsegs--; /* first segment is part of ulptx_sgl */
        n = extra + sizeof(struct fw_eth_tx_pkt_vm_wr) +
            sizeof(struct cpl_tx_pkt_core) +
            sizeof(struct ulptx_sgl) + 8 * ((3 * nsegs) / 2 + (nsegs & 1));

        return (howmany(n, 16));
}

static inline void
calculate_mbuf_len16(struct mbuf *m, bool vm_wr)
{
        const int lso = sizeof(struct cpl_tx_pkt_lso_core);
        const int tnl_lso = sizeof(struct cpl_tx_tnl_lso);

        if (vm_wr) {
                if (needs_tso(m))
                        set_mbuf_len16(m, txpkt_vm_len16(mbuf_nsegs(m), lso));
                else
                        set_mbuf_len16(m, txpkt_vm_len16(mbuf_nsegs(m), 0));
                return;
        }

        if (needs_tso(m)) {
                if (needs_vxlan_tso(m))
                        set_mbuf_len16(m, txpkt_len16(mbuf_nsegs(m), tnl_lso));
                else
                        set_mbuf_len16(m, txpkt_len16(mbuf_nsegs(m), lso));
        } else
                set_mbuf_len16(m, txpkt_len16(mbuf_nsegs(m), 0));
}

/*
 * len16 for a txpkts type 0 WR with a GL.  Does not include the firmware work
 * request header.
 */
static inline u_int
txpkts0_len16(u_int nsegs)
{
        u_int n;

        MPASS(nsegs > 0);

        nsegs--; /* first segment is part of ulptx_sgl */
        n = sizeof(struct ulp_txpkt) + sizeof(struct ulptx_idata) +
            sizeof(struct cpl_tx_pkt_core) + sizeof(struct ulptx_sgl) +
            8 * ((3 * nsegs) / 2 + (nsegs & 1));

        return (howmany(n, 16));
}

/*
 * len16 for a txpkts type 1 WR with a GL.  Does not include the firmware work
 * request header.
 */
static inline u_int
txpkts1_len16(void)
{
        u_int n;

        n = sizeof(struct cpl_tx_pkt_core) + sizeof(struct ulptx_sgl);

        return (howmany(n, 16));
}

static inline u_int
imm_payload(u_int ndesc)
{
        u_int n;

        n = ndesc * EQ_ESIZE - sizeof(struct fw_eth_tx_pkt_wr) -
            sizeof(struct cpl_tx_pkt_core);

        return (n);
}

static inline uint64_t
csum_to_ctrl(struct adapter *sc, struct mbuf *m)
{
        uint64_t ctrl;
        int csum_type, l2hlen, l3hlen;
        int x, y;
        static const uint8_t csum_types[3][2] = {
                {TX_CSUM_TCPIP, TX_CSUM_TCPIP6},
                {TX_CSUM_UDPIP, TX_CSUM_UDPIP6},
                {TX_CSUM_IP, 0}
        };

        M_ASSERTPKTHDR(m);

        if (!needs_hwcsum(m))
                return (F_TXPKT_IPCSUM_DIS | F_TXPKT_L4CSUM_DIS);

        MPASS(m->m_pkthdr.l2hlen >= ETHER_HDR_LEN);
        MPASS(m->m_pkthdr.l3hlen >= sizeof(struct ip));

        if (needs_vxlan_csum(m)) {
                MPASS(m->m_pkthdr.l4hlen > 0);
                MPASS(m->m_pkthdr.l5hlen > 0);
                MPASS(m->m_pkthdr.inner_l2hlen >= ETHER_HDR_LEN);
                MPASS(m->m_pkthdr.inner_l3hlen >= sizeof(struct ip));

                l2hlen = m->m_pkthdr.l2hlen + m->m_pkthdr.l3hlen +
                    m->m_pkthdr.l4hlen + m->m_pkthdr.l5hlen +
                    m->m_pkthdr.inner_l2hlen - ETHER_HDR_LEN;
                l3hlen = m->m_pkthdr.inner_l3hlen;
        } else {
                l2hlen = m->m_pkthdr.l2hlen - ETHER_HDR_LEN;
                l3hlen = m->m_pkthdr.l3hlen;
        }

        ctrl = 0;
        if (!needs_l3_csum(m))
                ctrl |= F_TXPKT_IPCSUM_DIS;

        if (m->m_pkthdr.csum_flags & (CSUM_IP_TCP | CSUM_INNER_IP_TCP |
            CSUM_IP6_TCP | CSUM_INNER_IP6_TCP))
                x = 0;  /* TCP */
        else if (m->m_pkthdr.csum_flags & (CSUM_IP_UDP | CSUM_INNER_IP_UDP |
            CSUM_IP6_UDP | CSUM_INNER_IP6_UDP))
                x = 1;  /* UDP */
        else
                x = 2;

        if (m->m_pkthdr.csum_flags & (CSUM_IP | CSUM_IP_TCP | CSUM_IP_UDP |
            CSUM_INNER_IP | CSUM_INNER_IP_TCP | CSUM_INNER_IP_UDP))
                y = 0;  /* IPv4 */
        else {
                MPASS(m->m_pkthdr.csum_flags & (CSUM_IP6_TCP | CSUM_IP6_UDP |
                    CSUM_INNER_IP6_TCP | CSUM_INNER_IP6_UDP));
                y = 1;  /* IPv6 */
        }
        /*
         * needs_hwcsum returned true earlier so there must be some kind of
         * checksum to calculate.
         */
        csum_type = csum_types[x][y];
        MPASS(csum_type != 0);
        if (csum_type == TX_CSUM_IP)
                ctrl |= F_TXPKT_L4CSUM_DIS;
        ctrl |= V_TXPKT_CSUM_TYPE(csum_type) | V_TXPKT_IPHDR_LEN(l3hlen);
        if (chip_id(sc) <= CHELSIO_T5)
                ctrl |= V_TXPKT_ETHHDR_LEN(l2hlen);
        else
                ctrl |= V_T6_TXPKT_ETHHDR_LEN(l2hlen);

        return (ctrl);
}

static inline void *
write_lso_cpl(void *cpl, struct mbuf *m0)
{
        struct cpl_tx_pkt_lso_core *lso;
        uint32_t ctrl;

        KASSERT(m0->m_pkthdr.l2hlen > 0 && m0->m_pkthdr.l3hlen > 0 &&
            m0->m_pkthdr.l4hlen > 0,
            ("%s: mbuf %p needs TSO but missing header lengths",
                __func__, m0));

        ctrl = V_LSO_OPCODE(CPL_TX_PKT_LSO) |
            F_LSO_FIRST_SLICE | F_LSO_LAST_SLICE |
            V_LSO_ETHHDR_LEN((m0->m_pkthdr.l2hlen - ETHER_HDR_LEN) >> 2) |
            V_LSO_IPHDR_LEN(m0->m_pkthdr.l3hlen >> 2) |
            V_LSO_TCPHDR_LEN(m0->m_pkthdr.l4hlen >> 2);
        if (m0->m_pkthdr.l3hlen == sizeof(struct ip6_hdr))
                ctrl |= F_LSO_IPV6;

        lso = cpl;
        lso->lso_ctrl = htobe32(ctrl);
        lso->ipid_ofst = htobe16(0);
        lso->mss = htobe16(m0->m_pkthdr.tso_segsz);
        lso->seqno_offset = htobe32(0);
        lso->len = htobe32(m0->m_pkthdr.len);

        return (lso + 1);
}

static void *
write_tnl_lso_cpl(void *cpl, struct mbuf *m0)
{
        struct cpl_tx_tnl_lso *tnl_lso = cpl;
        uint32_t ctrl;

        KASSERT(m0->m_pkthdr.inner_l2hlen > 0 &&
            m0->m_pkthdr.inner_l3hlen > 0 && m0->m_pkthdr.inner_l4hlen > 0 &&
            m0->m_pkthdr.inner_l5hlen > 0,
            ("%s: mbuf %p needs VXLAN_TSO but missing inner header lengths",
                __func__, m0));
        KASSERT(m0->m_pkthdr.l2hlen > 0 && m0->m_pkthdr.l3hlen > 0 &&
            m0->m_pkthdr.l4hlen > 0 && m0->m_pkthdr.l5hlen > 0,
            ("%s: mbuf %p needs VXLAN_TSO but missing outer header lengths",
                __func__, m0));

        /* Outer headers. */
        ctrl = V_CPL_TX_TNL_LSO_OPCODE(CPL_TX_TNL_LSO) |
            F_CPL_TX_TNL_LSO_FIRST | F_CPL_TX_TNL_LSO_LAST |
            V_CPL_TX_TNL_LSO_ETHHDRLENOUT(
                (m0->m_pkthdr.l2hlen - ETHER_HDR_LEN) >> 2) |
            V_CPL_TX_TNL_LSO_IPHDRLENOUT(m0->m_pkthdr.l3hlen >> 2) |
            F_CPL_TX_TNL_LSO_IPLENSETOUT;
        if (m0->m_pkthdr.l3hlen == sizeof(struct ip6_hdr))
                ctrl |= F_CPL_TX_TNL_LSO_IPV6OUT;
        else {
                ctrl |= F_CPL_TX_TNL_LSO_IPHDRCHKOUT |
                    F_CPL_TX_TNL_LSO_IPIDINCOUT;
        }
        tnl_lso->op_to_IpIdSplitOut = htobe32(ctrl);
        tnl_lso->IpIdOffsetOut = 0;
        tnl_lso->UdpLenSetOut_to_TnlHdrLen =
                htobe16(F_CPL_TX_TNL_LSO_UDPCHKCLROUT |
                    F_CPL_TX_TNL_LSO_UDPLENSETOUT |
                    V_CPL_TX_TNL_LSO_TNLHDRLEN(m0->m_pkthdr.l2hlen +
                        m0->m_pkthdr.l3hlen + m0->m_pkthdr.l4hlen +
                        m0->m_pkthdr.l5hlen) |
                    V_CPL_TX_TNL_LSO_TNLTYPE(TX_TNL_TYPE_VXLAN));
        tnl_lso->ipsecen_to_rocev2 = 0;
        tnl_lso->roce_eth = 0;

        /* Inner headers. */
        ctrl = V_CPL_TX_TNL_LSO_ETHHDRLEN(
            (m0->m_pkthdr.inner_l2hlen - ETHER_HDR_LEN) >> 2) |
            V_CPL_TX_TNL_LSO_IPHDRLEN(m0->m_pkthdr.inner_l3hlen >> 2) |
            V_CPL_TX_TNL_LSO_TCPHDRLEN(m0->m_pkthdr.inner_l4hlen >> 2);
        if (m0->m_pkthdr.inner_l3hlen == sizeof(struct ip6_hdr))
                ctrl |= F_CPL_TX_TNL_LSO_IPV6;
        tnl_lso->Flow_to_TcpHdrLen = htobe32(ctrl);
        tnl_lso->IpIdOffset = 0;
        tnl_lso->IpIdSplit_to_Mss =
            htobe16(V_CPL_TX_TNL_LSO_MSS(m0->m_pkthdr.tso_segsz));
        tnl_lso->TCPSeqOffset = 0;
        tnl_lso->EthLenOffset_Size =
            htobe32(V_CPL_TX_TNL_LSO_SIZE(m0->m_pkthdr.len));

        return (tnl_lso + 1);
}

#define VM_TX_L2HDR_LEN 16      /* ethmacdst to vlantci */

/*
 * Write a VM txpkt WR for this packet to the hardware descriptors, update the
 * software descriptor, and advance the pidx.  It is guaranteed that enough
 * descriptors are available.
 *
 * The return value is the # of hardware descriptors used.
 */
static u_int
write_txpkt_vm_wr(struct adapter *sc, struct sge_txq *txq, struct mbuf *m0)
{
        struct sge_eq *eq;
        struct fw_eth_tx_pkt_vm_wr *wr;
        struct tx_sdesc *txsd;
        struct cpl_tx_pkt_core *cpl;
        uint32_t ctrl;  /* used in many unrelated places */
        uint64_t ctrl1;
        int len16, ndesc, pktlen;
        caddr_t dst;

        TXQ_LOCK_ASSERT_OWNED(txq);
        M_ASSERTPKTHDR(m0);

        len16 = mbuf_len16(m0);
        pktlen = m0->m_pkthdr.len;
        ctrl = sizeof(struct cpl_tx_pkt_core);
        if (needs_tso(m0))
                ctrl += sizeof(struct cpl_tx_pkt_lso_core);
        ndesc = tx_len16_to_desc(len16);

        /* Firmware work request header */
        eq = &txq->eq;
        wr = (void *)&eq->desc[eq->pidx];
        wr->op_immdlen = htobe32(V_FW_WR_OP(FW_ETH_TX_PKT_VM_WR) |
            V_FW_ETH_TX_PKT_WR_IMMDLEN(ctrl));

        ctrl = V_FW_WR_LEN16(len16);
        wr->equiq_to_len16 = htobe32(ctrl);
        wr->r3[0] = 0;
        wr->r3[1] = 0;

        /*
         * Copy over ethmacdst, ethmacsrc, ethtype, and vlantci.
         * vlantci is ignored unless the ethtype is 0x8100, so it's
         * simpler to always copy it rather than making it
         * conditional.  Also, it seems that we do not have to set
         * vlantci or fake the ethtype when doing VLAN tag insertion.
         */
        m_copydata(m0, 0, VM_TX_L2HDR_LEN, wr->ethmacdst);

        if (needs_tso(m0)) {
                cpl = write_lso_cpl(wr + 1, m0);
                txq->tso_wrs++;
        } else
                cpl = (void *)(wr + 1);

        /* Checksum offload */
        ctrl1 = csum_to_ctrl(sc, m0);
        if (ctrl1 != (F_TXPKT_IPCSUM_DIS | F_TXPKT_L4CSUM_DIS))
                txq->txcsum++;  /* some hardware assistance provided */

        /* VLAN tag insertion */
        if (needs_vlan_insertion(m0)) {
                ctrl1 |= F_TXPKT_VLAN_VLD |
                    V_TXPKT_VLAN(m0->m_pkthdr.ether_vtag);
                txq->vlan_insertion++;
        } else if (sc->vlan_id)
                ctrl1 |= F_TXPKT_VLAN_VLD | V_TXPKT_VLAN(sc->vlan_id);

        /* CPL header */
        cpl->ctrl0 = txq->cpl_ctrl0;
        cpl->pack = 0;
        cpl->len = htobe16(pktlen);
        cpl->ctrl1 = htobe64(ctrl1);

        /* SGL */
        dst = (void *)(cpl + 1);

        /*
         * A packet using TSO will use up an entire descriptor for the
         * firmware work request header, LSO CPL, and TX_PKT_XT CPL.
         * If this descriptor is the last descriptor in the ring, wrap
         * around to the front of the ring explicitly for the start of
         * the sgl.
         */
        if (dst == (void *)&eq->desc[eq->sidx]) {
                dst = (void *)&eq->desc[0];
                write_gl_to_txd(txq, m0, &dst, 0);
        } else
                write_gl_to_txd(txq, m0, &dst, eq->sidx - ndesc < eq->pidx);
        txq->sgl_wrs++;
        txq->txpkt_wrs++;

        txsd = &txq->sdesc[eq->pidx];
        txsd->m = m0;
        txsd->desc_used = ndesc;

        return (ndesc);
}

/*
 * Write a raw WR to the hardware descriptors, update the software
 * descriptor, and advance the pidx.  It is guaranteed that enough
 * descriptors are available.
 *
 * The return value is the # of hardware descriptors used.
 */
static u_int
write_raw_wr(struct sge_txq *txq, void *wr, struct mbuf *m0, u_int available)
{
        struct sge_eq *eq = &txq->eq;
        struct tx_sdesc *txsd;
        struct mbuf *m;
        caddr_t dst;
        int len16, ndesc;

        len16 = mbuf_len16(m0);
        ndesc = tx_len16_to_desc(len16);
        MPASS(ndesc <= available);

        dst = wr;
        for (m = m0; m != NULL; m = m->m_next)
                copy_to_txd(eq, mtod(m, caddr_t), &dst, m->m_len);

        txq->raw_wrs++;

        txsd = &txq->sdesc[eq->pidx];
        txsd->m = m0;
        txsd->desc_used = ndesc;

        return (ndesc);
}

/*
 * Write a txpkt WR for this packet to the hardware descriptors, update the
 * software descriptor, and advance the pidx.  It is guaranteed that enough
 * descriptors are available.
 *
 * The return value is the # of hardware descriptors used.
 */
static u_int
write_txpkt_wr(struct adapter *sc, struct sge_txq *txq, struct mbuf *m0,
    u_int available)
{
        struct sge_eq *eq;
        struct fw_eth_tx_pkt_wr *wr;
        struct tx_sdesc *txsd;
        struct cpl_tx_pkt_core *cpl;
        uint32_t ctrl;  /* used in many unrelated places */
        uint64_t ctrl1;
        int len16, ndesc, pktlen, nsegs;
        caddr_t dst;

        TXQ_LOCK_ASSERT_OWNED(txq);
        M_ASSERTPKTHDR(m0);

        len16 = mbuf_len16(m0);
        nsegs = mbuf_nsegs(m0);
        pktlen = m0->m_pkthdr.len;
        ctrl = sizeof(struct cpl_tx_pkt_core);
        if (needs_tso(m0)) {
                if (needs_vxlan_tso(m0))
                        ctrl += sizeof(struct cpl_tx_tnl_lso);
                else
                        ctrl += sizeof(struct cpl_tx_pkt_lso_core);
        } else if (!(mbuf_cflags(m0) & MC_NOMAP) && pktlen <= imm_payload(2) &&
            available >= 2) {
                /* Immediate data.  Recalculate len16 and set nsegs to 0. */
                ctrl += pktlen;
                len16 = howmany(sizeof(struct fw_eth_tx_pkt_wr) +
                    sizeof(struct cpl_tx_pkt_core) + pktlen, 16);
                nsegs = 0;
        }
        ndesc = tx_len16_to_desc(len16);
        MPASS(ndesc <= available);

        /* Firmware work request header */
        eq = &txq->eq;
        wr = (void *)&eq->desc[eq->pidx];
        wr->op_immdlen = htobe32(V_FW_WR_OP(FW_ETH_TX_PKT_WR) |
            V_FW_ETH_TX_PKT_WR_IMMDLEN(ctrl));

        ctrl = V_FW_WR_LEN16(len16);
        wr->equiq_to_len16 = htobe32(ctrl);
        wr->r3 = 0;

        if (needs_tso(m0)) {
                if (needs_vxlan_tso(m0)) {
                        cpl = write_tnl_lso_cpl(wr + 1, m0);
                        txq->vxlan_tso_wrs++;
                } else {
                        cpl = write_lso_cpl(wr + 1, m0);
                        txq->tso_wrs++;
                }
        } else
                cpl = (void *)(wr + 1);

        /* Checksum offload */
        ctrl1 = csum_to_ctrl(sc, m0);
        if (ctrl1 != (F_TXPKT_IPCSUM_DIS | F_TXPKT_L4CSUM_DIS)) {
                /* some hardware assistance provided */
                if (needs_vxlan_csum(m0))
                        txq->vxlan_txcsum++;
                else
                        txq->txcsum++;
        }

        /* VLAN tag insertion */
        if (needs_vlan_insertion(m0)) {
                ctrl1 |= F_TXPKT_VLAN_VLD |
                    V_TXPKT_VLAN(m0->m_pkthdr.ether_vtag);
                txq->vlan_insertion++;
        }

        /* CPL header */
        cpl->ctrl0 = txq->cpl_ctrl0;
        cpl->pack = 0;
        cpl->len = htobe16(pktlen);
        cpl->ctrl1 = htobe64(ctrl1);

        /* SGL */
        dst = (void *)(cpl + 1);
        if (__predict_false((uintptr_t)dst == (uintptr_t)&eq->desc[eq->sidx]))
                dst = (caddr_t)&eq->desc[0];
        if (nsegs > 0) {

                write_gl_to_txd(txq, m0, &dst, eq->sidx - ndesc < eq->pidx);
                txq->sgl_wrs++;
        } else {
                struct mbuf *m;

                for (m = m0; m != NULL; m = m->m_next) {
                        copy_to_txd(eq, mtod(m, caddr_t), &dst, m->m_len);
#ifdef INVARIANTS
                        pktlen -= m->m_len;
#endif
                }
#ifdef INVARIANTS
                KASSERT(pktlen == 0, ("%s: %d bytes left.", __func__, pktlen));
#endif
                txq->imm_wrs++;
        }

        txq->txpkt_wrs++;

        txsd = &txq->sdesc[eq->pidx];
        txsd->m = m0;
        txsd->desc_used = ndesc;

        return (ndesc);
}

static inline bool
cmp_l2hdr(struct txpkts *txp, struct mbuf *m)
{
        int len;

        MPASS(txp->npkt > 0);
        MPASS(m->m_len >= VM_TX_L2HDR_LEN);

        if (txp->ethtype == be16toh(ETHERTYPE_VLAN))
                len = VM_TX_L2HDR_LEN;
        else
                len = sizeof(struct ether_header);

        return (memcmp(m->m_data, &txp->ethmacdst[0], len) != 0);
}

static inline void
save_l2hdr(struct txpkts *txp, struct mbuf *m)
{
        MPASS(m->m_len >= VM_TX_L2HDR_LEN);

        memcpy(&txp->ethmacdst[0], mtod(m, const void *), VM_TX_L2HDR_LEN);
}

static int
add_to_txpkts_vf(struct adapter *sc, struct sge_txq *txq, struct mbuf *m,
    int avail, bool *send)
{
        struct txpkts *txp = &txq->txp;

        /* Cannot have TSO and coalesce at the same time. */
        if (cannot_use_txpkts(m)) {
cannot_coalesce:
                *send = txp->npkt > 0;
                return (EINVAL);
        }

        /* VF allows coalescing of type 1 (1 GL) only */
        if (mbuf_nsegs(m) > 1)
                goto cannot_coalesce;

        *send = false;
        if (txp->npkt > 0) {
                MPASS(tx_len16_to_desc(txp->len16) <= avail);
                MPASS(txp->npkt < txp->max_npkt);
                MPASS(txp->wr_type == 1);       /* VF supports type 1 only */

                if (tx_len16_to_desc(txp->len16 + txpkts1_len16()) > avail) {
retry_after_send:
                        *send = true;
                        return (EAGAIN);
                }
                if (m->m_pkthdr.len + txp->plen > 65535)
                        goto retry_after_send;
                if (cmp_l2hdr(txp, m))
                        goto retry_after_send;

                txp->len16 += txpkts1_len16();
                txp->plen += m->m_pkthdr.len;
                txp->mb[txp->npkt++] = m;
                if (txp->npkt == txp->max_npkt)
                        *send = true;
        } else {
                txp->len16 = howmany(sizeof(struct fw_eth_tx_pkts_vm_wr), 16) +
                    txpkts1_len16();
                if (tx_len16_to_desc(txp->len16) > avail)
                        goto cannot_coalesce;
                txp->npkt = 1;
                txp->wr_type = 1;
                txp->plen = m->m_pkthdr.len;
                txp->mb[0] = m;
                save_l2hdr(txp, m);
        }
        return (0);
}

static int
add_to_txpkts_pf(struct adapter *sc, struct sge_txq *txq, struct mbuf *m,
    int avail, bool *send)
{
        struct txpkts *txp = &txq->txp;
        int nsegs;

        MPASS(!(sc->flags & IS_VF));

        /* Cannot have TSO and coalesce at the same time. */
        if (cannot_use_txpkts(m)) {
cannot_coalesce:
                *send = txp->npkt > 0;
                return (EINVAL);
        }

        *send = false;
        nsegs = mbuf_nsegs(m);
        if (txp->npkt == 0) {
                if (m->m_pkthdr.len > 65535)
                        goto cannot_coalesce;
                if (nsegs > 1) {
                        txp->wr_type = 0;
                        txp->len16 =
                            howmany(sizeof(struct fw_eth_tx_pkts_wr), 16) +
                            txpkts0_len16(nsegs);
                } else {
                        txp->wr_type = 1;
                        txp->len16 =
                            howmany(sizeof(struct fw_eth_tx_pkts_wr), 16) +
                            txpkts1_len16();
                }
                if (tx_len16_to_desc(txp->len16) > avail)
                        goto cannot_coalesce;
                txp->npkt = 1;
                txp->plen = m->m_pkthdr.len;
                txp->mb[0] = m;
        } else {
                MPASS(tx_len16_to_desc(txp->len16) <= avail);
                MPASS(txp->npkt < txp->max_npkt);

                if (m->m_pkthdr.len + txp->plen > 65535) {
retry_after_send:
                        *send = true;
                        return (EAGAIN);
                }

                MPASS(txp->wr_type == 0 || txp->wr_type == 1);
                if (txp->wr_type == 0) {
                        if (tx_len16_to_desc(txp->len16 +
                            txpkts0_len16(nsegs)) > min(avail, SGE_MAX_WR_NDESC))
                                goto retry_after_send;
                        txp->len16 += txpkts0_len16(nsegs);
                } else {
                        if (nsegs != 1)
                                goto retry_after_send;
                        if (tx_len16_to_desc(txp->len16 + txpkts1_len16()) >
                            avail)
                                goto retry_after_send;
                        txp->len16 += txpkts1_len16();
                }

                txp->plen += m->m_pkthdr.len;
                txp->mb[txp->npkt++] = m;
                if (txp->npkt == txp->max_npkt)
                        *send = true;
        }
        return (0);
}

/*
 * Write a txpkts WR for the packets in txp to the hardware descriptors, update
 * the software descriptor, and advance the pidx.  It is guaranteed that enough
 * descriptors are available.
 *
 * The return value is the # of hardware descriptors used.
 */
static u_int
write_txpkts_wr(struct adapter *sc, struct sge_txq *txq)
{
        const struct txpkts *txp = &txq->txp;
        struct sge_eq *eq = &txq->eq;
        struct fw_eth_tx_pkts_wr *wr;
        struct tx_sdesc *txsd;
        struct cpl_tx_pkt_core *cpl;
        uint64_t ctrl1;
        int ndesc, i, checkwrap;
        struct mbuf *m, *last;
        void *flitp;

        TXQ_LOCK_ASSERT_OWNED(txq);
        MPASS(txp->npkt > 0);
        MPASS(txp->len16 <= howmany(SGE_MAX_WR_LEN, 16));

        wr = (void *)&eq->desc[eq->pidx];
        wr->op_pkd = htobe32(V_FW_WR_OP(FW_ETH_TX_PKTS_WR));
        wr->equiq_to_len16 = htobe32(V_FW_WR_LEN16(txp->len16));
        wr->plen = htobe16(txp->plen);
        wr->npkt = txp->npkt;
        wr->r3 = 0;
        wr->type = txp->wr_type;
        flitp = wr + 1;

        /*
         * At this point we are 16B into a hardware descriptor.  If checkwrap is
         * set then we know the WR is going to wrap around somewhere.  We'll
         * check for that at appropriate points.
         */
        ndesc = tx_len16_to_desc(txp->len16);
        last = NULL;
        checkwrap = eq->sidx - ndesc < eq->pidx;
        for (i = 0; i < txp->npkt; i++) {
                m = txp->mb[i];
                if (txp->wr_type == 0) {
                        struct ulp_txpkt *ulpmc;
                        struct ulptx_idata *ulpsc;

                        /* ULP master command */
                        ulpmc = flitp;
                        ulpmc->cmd_dest = htobe32(V_ULPTX_CMD(ULP_TX_PKT) |
                            V_ULP_TXPKT_DEST(0) | V_ULP_TXPKT_FID(eq->iqid));
                        ulpmc->len = htobe32(txpkts0_len16(mbuf_nsegs(m)));

                        /* ULP subcommand */
                        ulpsc = (void *)(ulpmc + 1);
                        ulpsc->cmd_more = htobe32(V_ULPTX_CMD(ULP_TX_SC_IMM) |
                            F_ULP_TX_SC_MORE);
                        ulpsc->len = htobe32(sizeof(struct cpl_tx_pkt_core));

                        cpl = (void *)(ulpsc + 1);
                        if (checkwrap &&
                            (uintptr_t)cpl == (uintptr_t)&eq->desc[eq->sidx])
                                cpl = (void *)&eq->desc[0];
                } else {
                        cpl = flitp;
                }

                /* Checksum offload */
                ctrl1 = csum_to_ctrl(sc, m);
                if (ctrl1 != (F_TXPKT_IPCSUM_DIS | F_TXPKT_L4CSUM_DIS)) {
                        /* some hardware assistance provided */
                        if (needs_vxlan_csum(m))
                                txq->vxlan_txcsum++;
                        else
                                txq->txcsum++;
                }

                /* VLAN tag insertion */
                if (needs_vlan_insertion(m)) {
                        ctrl1 |= F_TXPKT_VLAN_VLD |
                            V_TXPKT_VLAN(m->m_pkthdr.ether_vtag);
                        txq->vlan_insertion++;
                }

                /* CPL header */
                cpl->ctrl0 = txq->cpl_ctrl0;
                cpl->pack = 0;
                cpl->len = htobe16(m->m_pkthdr.len);
                cpl->ctrl1 = htobe64(ctrl1);

                flitp = cpl + 1;
                if (checkwrap &&
                    (uintptr_t)flitp == (uintptr_t)&eq->desc[eq->sidx])
                        flitp = (void *)&eq->desc[0];

                write_gl_to_txd(txq, m, (caddr_t *)(&flitp), checkwrap);

                if (last != NULL)
                        last->m_nextpkt = m;
                last = m;
        }

        txq->sgl_wrs++;
        if (txp->wr_type == 0) {
                txq->txpkts0_pkts += txp->npkt;
                txq->txpkts0_wrs++;
        } else {
                txq->txpkts1_pkts += txp->npkt;
                txq->txpkts1_wrs++;
        }

        txsd = &txq->sdesc[eq->pidx];
        txsd->m = txp->mb[0];
        txsd->desc_used = ndesc;

        return (ndesc);
}

static u_int
write_txpkts_vm_wr(struct adapter *sc, struct sge_txq *txq)
{
        const struct txpkts *txp = &txq->txp;
        struct sge_eq *eq = &txq->eq;
        struct fw_eth_tx_pkts_vm_wr *wr;
        struct tx_sdesc *txsd;
        struct cpl_tx_pkt_core *cpl;
        uint64_t ctrl1;
        int ndesc, i;
        struct mbuf *m, *last;
        void *flitp;

        TXQ_LOCK_ASSERT_OWNED(txq);
        MPASS(txp->npkt > 0);
        MPASS(txp->wr_type == 1);       /* VF supports type 1 only */
        MPASS(txp->mb[0] != NULL);
        MPASS(txp->len16 <= howmany(SGE_MAX_WR_LEN, 16));

        wr = (void *)&eq->desc[eq->pidx];
        wr->op_pkd = htobe32(V_FW_WR_OP(FW_ETH_TX_PKTS_VM_WR));
        wr->equiq_to_len16 = htobe32(V_FW_WR_LEN16(txp->len16));
        wr->r3 = 0;
        wr->plen = htobe16(txp->plen);
        wr->npkt = txp->npkt;
        wr->r4 = 0;
        memcpy(&wr->ethmacdst[0], &txp->ethmacdst[0], 16);
        flitp = wr + 1;

        /*
         * At this point we are 32B into a hardware descriptor.  Each mbuf in
         * the WR will take 32B so we check for the end of the descriptor ring
         * before writing odd mbufs (mb[1], 3, 5, ..)
         */
        ndesc = tx_len16_to_desc(txp->len16);
        last = NULL;
        for (i = 0; i < txp->npkt; i++) {
                m = txp->mb[i];
                if (i & 1 && (uintptr_t)flitp == (uintptr_t)&eq->desc[eq->sidx])
                        flitp = &eq->desc[0];
                cpl = flitp;

                /* Checksum offload */
                ctrl1 = csum_to_ctrl(sc, m);
                if (ctrl1 != (F_TXPKT_IPCSUM_DIS | F_TXPKT_L4CSUM_DIS))
                        txq->txcsum++;  /* some hardware assistance provided */

                /* VLAN tag insertion */
                if (needs_vlan_insertion(m)) {
                        ctrl1 |= F_TXPKT_VLAN_VLD |
                            V_TXPKT_VLAN(m->m_pkthdr.ether_vtag);
                        txq->vlan_insertion++;
                } else if (sc->vlan_id)
                        ctrl1 |= F_TXPKT_VLAN_VLD | V_TXPKT_VLAN(sc->vlan_id);

                /* CPL header */
                cpl->ctrl0 = txq->cpl_ctrl0;
                cpl->pack = 0;
                cpl->len = htobe16(m->m_pkthdr.len);
                cpl->ctrl1 = htobe64(ctrl1);

                flitp = cpl + 1;
                MPASS(mbuf_nsegs(m) == 1);
                write_gl_to_txd(txq, m, (caddr_t *)(&flitp), 0);

                if (last != NULL)
                        last->m_nextpkt = m;
                last = m;
        }

        txq->sgl_wrs++;
        txq->txpkts1_pkts += txp->npkt;
        txq->txpkts1_wrs++;

        txsd = &txq->sdesc[eq->pidx];
        txsd->m = txp->mb[0];
        txsd->desc_used = ndesc;

        return (ndesc);
}

/*
 * If the SGL ends on an address that is not 16 byte aligned, this function will
 * add a 0 filled flit at the end.
 */
static void
write_gl_to_txd(struct sge_txq *txq, struct mbuf *m, caddr_t *to, int checkwrap)
{
        struct sge_eq *eq = &txq->eq;
        struct sglist *gl = txq->gl;
        struct sglist_seg *seg;
        __be64 *flitp, *wrap;
        struct ulptx_sgl *usgl;
        int i, nflits, nsegs;

        KASSERT(((uintptr_t)(*to) & 0xf) == 0,
            ("%s: SGL must start at a 16 byte boundary: %p", __func__, *to));
        MPASS((uintptr_t)(*to) >= (uintptr_t)&eq->desc[0]);
        MPASS((uintptr_t)(*to) < (uintptr_t)&eq->desc[eq->sidx]);

        get_pkt_gl(m, gl);
        nsegs = gl->sg_nseg;
        MPASS(nsegs > 0);

        nflits = (3 * (nsegs - 1)) / 2 + ((nsegs - 1) & 1) + 2;
        flitp = (__be64 *)(*to);
        wrap = (__be64 *)(&eq->desc[eq->sidx]);
        seg = &gl->sg_segs[0];
        usgl = (void *)flitp;

        /*
         * We start at a 16 byte boundary somewhere inside the tx descriptor
         * ring, so we're at least 16 bytes away from the status page.  There is
         * no chance of a wrap around in the middle of usgl (which is 16 bytes).
         */

        usgl->cmd_nsge = htobe32(V_ULPTX_CMD(ULP_TX_SC_DSGL) |
            V_ULPTX_NSGE(nsegs));
        usgl->len0 = htobe32(seg->ss_len);
        usgl->addr0 = htobe64(seg->ss_paddr);
        seg++;

        if (checkwrap == 0 || (uintptr_t)(flitp + nflits) <= (uintptr_t)wrap) {

                /* Won't wrap around at all */

                for (i = 0; i < nsegs - 1; i++, seg++) {
                        usgl->sge[i / 2].len[i & 1] = htobe32(seg->ss_len);
                        usgl->sge[i / 2].addr[i & 1] = htobe64(seg->ss_paddr);
                }
                if (i & 1)
                        usgl->sge[i / 2].len[1] = htobe32(0);
                flitp += nflits;
        } else {

                /* Will wrap somewhere in the rest of the SGL */

                /* 2 flits already written, write the rest flit by flit */
                flitp = (void *)(usgl + 1);
                for (i = 0; i < nflits - 2; i++) {
                        if (flitp == wrap)
                                flitp = (void *)eq->desc;
                        *flitp++ = get_flit(seg, nsegs - 1, i);
                }
        }

        if (nflits & 1) {
                MPASS(((uintptr_t)flitp) & 0xf);
                *flitp++ = 0;
        }

        MPASS((((uintptr_t)flitp) & 0xf) == 0);
        if (__predict_false(flitp == wrap))
                *to = (void *)eq->desc;
        else
                *to = (void *)flitp;
}

static inline void
copy_to_txd(struct sge_eq *eq, caddr_t from, caddr_t *to, int len)
{

        MPASS((uintptr_t)(*to) >= (uintptr_t)&eq->desc[0]);
        MPASS((uintptr_t)(*to) < (uintptr_t)&eq->desc[eq->sidx]);

        if (__predict_true((uintptr_t)(*to) + len <=
            (uintptr_t)&eq->desc[eq->sidx])) {
                bcopy(from, *to, len);
                (*to) += len;
        } else {
                int portion = (uintptr_t)&eq->desc[eq->sidx] - (uintptr_t)(*to);

                bcopy(from, *to, portion);
                from += portion;
                portion = len - portion;        /* remaining */
                bcopy(from, (void *)eq->desc, portion);
                (*to) = (caddr_t)eq->desc + portion;
        }
}

static inline void
ring_eq_db(struct adapter *sc, struct sge_eq *eq, u_int n)
{
        u_int db;

        MPASS(n > 0);

        db = eq->doorbells;
        if (n > 1)
                clrbit(&db, DOORBELL_WCWR);
        wmb();

        switch (ffs(db) - 1) {
        case DOORBELL_UDB:
                *eq->udb = htole32(V_QID(eq->udb_qid) | V_PIDX(n));
                break;

        case DOORBELL_WCWR: {
                volatile uint64_t *dst, *src;
                int i;

                /*
                 * Queues whose 128B doorbell segment fits in the page do not
                 * use relative qid (udb_qid is always 0).  Only queues with
                 * doorbell segments can do WCWR.
                 */
                KASSERT(eq->udb_qid == 0 && n == 1,
                    ("%s: inappropriate doorbell (0x%x, %d, %d) for eq %p",
                    __func__, eq->doorbells, n, eq->dbidx, eq));

                dst = (volatile void *)((uintptr_t)eq->udb + UDBS_WR_OFFSET -
                    UDBS_DB_OFFSET);
                i = eq->dbidx;
                src = (void *)&eq->desc[i];
                while (src != (void *)&eq->desc[i + 1])
                        *dst++ = *src++;
                wmb();
                break;
        }

        case DOORBELL_UDBWC:
                *eq->udb = htole32(V_QID(eq->udb_qid) | V_PIDX(n));
                wmb();
                break;

        case DOORBELL_KDB:
                t4_write_reg(sc, sc->sge_kdoorbell_reg,
                    V_QID(eq->cntxt_id) | V_PIDX(n));
                break;
        }

        IDXINCR(eq->dbidx, n, eq->sidx);
}

static inline u_int
reclaimable_tx_desc(struct sge_eq *eq)
{
        uint16_t hw_cidx;

        hw_cidx = read_hw_cidx(eq);
        return (IDXDIFF(hw_cidx, eq->cidx, eq->sidx));
}

static inline u_int
total_available_tx_desc(struct sge_eq *eq)
{
        uint16_t hw_cidx, pidx;

        hw_cidx = read_hw_cidx(eq);
        pidx = eq->pidx;

        if (pidx == hw_cidx)
                return (eq->sidx - 1);
        else
                return (IDXDIFF(hw_cidx, pidx, eq->sidx) - 1);
}

static inline uint16_t
read_hw_cidx(struct sge_eq *eq)
{
        struct sge_qstat *spg = (void *)&eq->desc[eq->sidx];
        uint16_t cidx = spg->cidx;      /* stable snapshot */

        return (be16toh(cidx));
}

/*
 * Reclaim 'n' descriptors approximately.
 */
static u_int
reclaim_tx_descs(struct sge_txq *txq, u_int n)
{
        struct tx_sdesc *txsd;
        struct sge_eq *eq = &txq->eq;
        u_int can_reclaim, reclaimed;

        TXQ_LOCK_ASSERT_OWNED(txq);
        MPASS(n > 0);

        reclaimed = 0;
        can_reclaim = reclaimable_tx_desc(eq);
        while (can_reclaim && reclaimed < n) {
                int ndesc;
                struct mbuf *m, *nextpkt;

                txsd = &txq->sdesc[eq->cidx];
                ndesc = txsd->desc_used;

                /* Firmware doesn't return "partial" credits. */
                KASSERT(can_reclaim >= ndesc,
                    ("%s: unexpected number of credits: %d, %d",
                    __func__, can_reclaim, ndesc));
                KASSERT(ndesc != 0,
                    ("%s: descriptor with no credits: cidx %d",
                    __func__, eq->cidx));

                for (m = txsd->m; m != NULL; m = nextpkt) {
                        nextpkt = m->m_nextpkt;
                        m->m_nextpkt = NULL;
                        m_freem(m);
                }
                reclaimed += ndesc;
                can_reclaim -= ndesc;
                IDXINCR(eq->cidx, ndesc, eq->sidx);
        }

        return (reclaimed);
}

static void
tx_reclaim(void *arg, int n)
{
        struct sge_txq *txq = arg;
        struct sge_eq *eq = &txq->eq;

        do {
                if (TXQ_TRYLOCK(txq) == 0)
                        break;
                n = reclaim_tx_descs(txq, 32);
                if (eq->cidx == eq->pidx)
                        eq->equeqidx = eq->pidx;
                TXQ_UNLOCK(txq);
        } while (n > 0);
}

static __be64
get_flit(struct sglist_seg *segs, int nsegs, int idx)
{
        int i = (idx / 3) * 2;

        switch (idx % 3) {
        case 0: {
                uint64_t rc;

                rc = (uint64_t)segs[i].ss_len << 32;
                if (i + 1 < nsegs)
                        rc |= (uint64_t)(segs[i + 1].ss_len);

                return (htobe64(rc));
        }
        case 1:
                return (htobe64(segs[i].ss_paddr));
        case 2:
                return (htobe64(segs[i + 1].ss_paddr));
        }

        return (0);
}

static int
find_refill_source(struct adapter *sc, int maxp, bool packing)
{
        int i, zidx = -1;
        struct rx_buf_info *rxb = &sc->sge.rx_buf_info[0];

        if (packing) {
                for (i = 0; i < SW_ZONE_SIZES; i++, rxb++) {
                        if (rxb->hwidx2 == -1)
                                continue;
                        if (rxb->size1 < PAGE_SIZE &&
                            rxb->size1 < largest_rx_cluster)
                                continue;
                        if (rxb->size1 > largest_rx_cluster)
                                break;
                        MPASS(rxb->size1 - rxb->size2 >= CL_METADATA_SIZE);
                        if (rxb->size2 >= maxp)
                                return (i);
                        zidx = i;
                }
        } else {
                for (i = 0; i < SW_ZONE_SIZES; i++, rxb++) {
                        if (rxb->hwidx1 == -1)
                                continue;
                        if (rxb->size1 > largest_rx_cluster)
                                break;
                        if (rxb->size1 >= maxp)
                                return (i);
                        zidx = i;
                }
        }

        return (zidx);
}

static void
add_fl_to_sfl(struct adapter *sc, struct sge_fl *fl)
{
        mtx_lock(&sc->sfl_lock);
        FL_LOCK(fl);
        if ((fl->flags & FL_DOOMED) == 0) {
                fl->flags |= FL_STARVING;
                TAILQ_INSERT_TAIL(&sc->sfl, fl, link);
                callout_reset(&sc->sfl_callout, hz / 5, refill_sfl, sc);
        }
        FL_UNLOCK(fl);
        mtx_unlock(&sc->sfl_lock);
}

static void
handle_wrq_egr_update(struct adapter *sc, struct sge_eq *eq)
{
        struct sge_wrq *wrq = (void *)eq;

        atomic_readandclear_int(&eq->equiq);
        taskqueue_enqueue(sc->tq[eq->port_id], &wrq->wrq_tx_task);
}

static void
handle_eth_egr_update(struct adapter *sc, struct sge_eq *eq)
{
        struct sge_txq *txq = (void *)eq;

        MPASS(eq->type == EQ_ETH);

        atomic_readandclear_int(&eq->equiq);
        if (mp_ring_is_idle(txq->r))
                taskqueue_enqueue(sc->tq[eq->port_id], &txq->tx_reclaim_task);
        else
                mp_ring_check_drainage(txq->r, 64);
}

static int
handle_sge_egr_update(struct sge_iq *iq, const struct rss_header *rss,
    struct mbuf *m)
{
        const struct cpl_sge_egr_update *cpl = (const void *)(rss + 1);
        unsigned int qid = G_EGR_QID(ntohl(cpl->opcode_qid));
        struct adapter *sc = iq->adapter;
        struct sge *s = &sc->sge;
        struct sge_eq *eq;
        static void (*h[])(struct adapter *, struct sge_eq *) = {NULL,
                &handle_wrq_egr_update, &handle_eth_egr_update,
                &handle_wrq_egr_update};

        KASSERT(m == NULL, ("%s: payload with opcode %02x", __func__,
            rss->opcode));

        eq = s->eqmap[qid - s->eq_start - s->eq_base];
        (*h[eq->type])(sc, eq);

        return (0);
}

/* handle_fw_msg works for both fw4_msg and fw6_msg because this is valid */
CTASSERT(offsetof(struct cpl_fw4_msg, data) == \
    offsetof(struct cpl_fw6_msg, data));

static int
handle_fw_msg(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m)
{
        struct adapter *sc = iq->adapter;
        const struct cpl_fw6_msg *cpl = (const void *)(rss + 1);

        KASSERT(m == NULL, ("%s: payload with opcode %02x", __func__,
            rss->opcode));

        if (cpl->type == FW_TYPE_RSSCPL || cpl->type == FW6_TYPE_RSSCPL) {
                const struct rss_header *rss2;

                rss2 = (const struct rss_header *)&cpl->data[0];
                return (t4_cpl_handler[rss2->opcode](iq, rss2, m));
        }

        return (t4_fw_msg_handler[cpl->type](sc, &cpl->data[0]));
}

/**
 *      t4_handle_wrerr_rpl - process a FW work request error message
 *      @adap: the adapter
 *      @rpl: start of the FW message
 */
static int
t4_handle_wrerr_rpl(struct adapter *adap, const __be64 *rpl)
{
        u8 opcode = *(const u8 *)rpl;
        const struct fw_error_cmd *e = (const void *)rpl;
        unsigned int i;

        if (opcode != FW_ERROR_CMD) {
                log(LOG_ERR,
                    "%s: Received WRERR_RPL message with opcode %#x\n",
                    device_get_nameunit(adap->dev), opcode);
                return (EINVAL);
        }
        log(LOG_ERR, "%s: FW_ERROR (%s) ", device_get_nameunit(adap->dev),
            G_FW_ERROR_CMD_FATAL(be32toh(e->op_to_type)) ? "fatal" :
            "non-fatal");
        switch (G_FW_ERROR_CMD_TYPE(be32toh(e->op_to_type))) {
        case FW_ERROR_TYPE_EXCEPTION:
                log(LOG_ERR, "exception info:\n");
                for (i = 0; i < nitems(e->u.exception.info); i++)
                        log(LOG_ERR, "%s%08x", i == 0 ? "\t" : " ",
                            be32toh(e->u.exception.info[i]));
                log(LOG_ERR, "\n");
                break;
        case FW_ERROR_TYPE_HWMODULE:
                log(LOG_ERR, "HW module regaddr %08x regval %08x\n",
                    be32toh(e->u.hwmodule.regaddr),
                    be32toh(e->u.hwmodule.regval));
                break;
        case FW_ERROR_TYPE_WR:
                log(LOG_ERR, "WR cidx %d PF %d VF %d eqid %d hdr:\n",
                    be16toh(e->u.wr.cidx),
                    G_FW_ERROR_CMD_PFN(be16toh(e->u.wr.pfn_vfn)),
                    G_FW_ERROR_CMD_VFN(be16toh(e->u.wr.pfn_vfn)),
                    be32toh(e->u.wr.eqid));
                for (i = 0; i < nitems(e->u.wr.wrhdr); i++)
                        log(LOG_ERR, "%s%02x", i == 0 ? "\t" : " ",
                            e->u.wr.wrhdr[i]);
                log(LOG_ERR, "\n");
                break;
        case FW_ERROR_TYPE_ACL:
                log(LOG_ERR, "ACL cidx %d PF %d VF %d eqid %d %s",
                    be16toh(e->u.acl.cidx),
                    G_FW_ERROR_CMD_PFN(be16toh(e->u.acl.pfn_vfn)),
                    G_FW_ERROR_CMD_VFN(be16toh(e->u.acl.pfn_vfn)),
                    be32toh(e->u.acl.eqid),
                    G_FW_ERROR_CMD_MV(be16toh(e->u.acl.mv_pkd)) ? "vlanid" :
                    "MAC");
                for (i = 0; i < nitems(e->u.acl.val); i++)
                        log(LOG_ERR, " %02x", e->u.acl.val[i]);
                log(LOG_ERR, "\n");
                break;
        default:
                log(LOG_ERR, "type %#x\n",
                    G_FW_ERROR_CMD_TYPE(be32toh(e->op_to_type)));
                return (EINVAL);
        }
        return (0);
}

static inline bool
bufidx_used(struct adapter *sc, int idx)
{
        struct rx_buf_info *rxb = &sc->sge.rx_buf_info[0];
        int i;

        for (i = 0; i < SW_ZONE_SIZES; i++, rxb++) {
                if (rxb->size1 > largest_rx_cluster)
                        continue;
                if (rxb->hwidx1 == idx || rxb->hwidx2 == idx)
                        return (true);
        }

        return (false);
}

static int
sysctl_bufsizes(SYSCTL_HANDLER_ARGS)
{
        struct adapter *sc = arg1;
        struct sge_params *sp = &sc->params.sge;
        int i, rc;
        struct sbuf sb;
        char c;

        sbuf_new(&sb, NULL, 128, SBUF_AUTOEXTEND);
        for (i = 0; i < SGE_FLBUF_SIZES; i++) {
                if (bufidx_used(sc, i))
                        c = '*';
                else
                        c = '\0';

                sbuf_printf(&sb, "%u%c ", sp->sge_fl_buffer_size[i], c);
        }
        sbuf_trim(&sb);
        sbuf_finish(&sb);
        rc = sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req);
        sbuf_delete(&sb);
        return (rc);
}

#ifdef RATELIMIT
#if defined(INET) || defined(INET6)
/*
 * len16 for a txpkt WR with a GL.  Includes the firmware work request header.
 */
static inline u_int
txpkt_eo_len16(u_int nsegs, u_int immhdrs, u_int tso)
{
        u_int n;

        MPASS(immhdrs > 0);

        n = roundup2(sizeof(struct fw_eth_tx_eo_wr) +
            sizeof(struct cpl_tx_pkt_core) + immhdrs, 16);
        if (__predict_false(nsegs == 0))
                goto done;

        nsegs--; /* first segment is part of ulptx_sgl */
        n += sizeof(struct ulptx_sgl) + 8 * ((3 * nsegs) / 2 + (nsegs & 1));
        if (tso)
                n += sizeof(struct cpl_tx_pkt_lso_core);

done:
        return (howmany(n, 16));
}
#endif

#define ETID_FLOWC_NPARAMS 6
#define ETID_FLOWC_LEN (roundup2((sizeof(struct fw_flowc_wr) + \
    ETID_FLOWC_NPARAMS * sizeof(struct fw_flowc_mnemval)), 16))
#define ETID_FLOWC_LEN16 (howmany(ETID_FLOWC_LEN, 16))

#if defined(INET) || defined(INET6)
static int
send_etid_flowc_wr(struct cxgbe_rate_tag *cst, struct port_info *pi,
    struct vi_info *vi)
{
        struct wrq_cookie cookie;
        u_int pfvf = pi->adapter->pf << S_FW_VIID_PFN;
        struct fw_flowc_wr *flowc;

        mtx_assert(&cst->lock, MA_OWNED);
        MPASS((cst->flags & (EO_FLOWC_PENDING | EO_FLOWC_RPL_PENDING)) ==
            EO_FLOWC_PENDING);

        flowc = start_wrq_wr(&cst->eo_txq->wrq, ETID_FLOWC_LEN16, &cookie);
        if (__predict_false(flowc == NULL))
                return (ENOMEM);

        bzero(flowc, ETID_FLOWC_LEN);
        flowc->op_to_nparams = htobe32(V_FW_WR_OP(FW_FLOWC_WR) |
            V_FW_FLOWC_WR_NPARAMS(ETID_FLOWC_NPARAMS) | V_FW_WR_COMPL(0));
        flowc->flowid_len16 = htonl(V_FW_WR_LEN16(ETID_FLOWC_LEN16) |
            V_FW_WR_FLOWID(cst->etid));
        flowc->mnemval[0].mnemonic = FW_FLOWC_MNEM_PFNVFN;
        flowc->mnemval[0].val = htobe32(pfvf);
        /* Firmware expects hw port and will translate to channel itself. */
        flowc->mnemval[1].mnemonic = FW_FLOWC_MNEM_CH;
        flowc->mnemval[1].val = htobe32(pi->hw_port);
        flowc->mnemval[2].mnemonic = FW_FLOWC_MNEM_PORT;
        flowc->mnemval[2].val = htobe32(pi->hw_port);
        flowc->mnemval[3].mnemonic = FW_FLOWC_MNEM_IQID;
        flowc->mnemval[3].val = htobe32(cst->iqid);
        flowc->mnemval[4].mnemonic = FW_FLOWC_MNEM_EOSTATE;
        flowc->mnemval[4].val = htobe32(FW_FLOWC_MNEM_EOSTATE_ESTABLISHED);
        flowc->mnemval[5].mnemonic = FW_FLOWC_MNEM_SCHEDCLASS;
        flowc->mnemval[5].val = htobe32(cst->schedcl);

        commit_wrq_wr(&cst->eo_txq->wrq, flowc, &cookie);

        cst->flags &= ~EO_FLOWC_PENDING;
        cst->flags |= EO_FLOWC_RPL_PENDING;
        MPASS(cst->tx_credits >= ETID_FLOWC_LEN16);     /* flowc is first WR. */
        cst->tx_credits -= ETID_FLOWC_LEN16;

        return (0);
}
#endif

#define ETID_FLUSH_LEN16 (howmany(sizeof (struct fw_flowc_wr), 16))

void
send_etid_flush_wr(struct cxgbe_rate_tag *cst)
{
        struct fw_flowc_wr *flowc;
        struct wrq_cookie cookie;

        mtx_assert(&cst->lock, MA_OWNED);

        flowc = start_wrq_wr(&cst->eo_txq->wrq, ETID_FLUSH_LEN16, &cookie);
        if (__predict_false(flowc == NULL))
                CXGBE_UNIMPLEMENTED(__func__);

        bzero(flowc, ETID_FLUSH_LEN16 * 16);
        flowc->op_to_nparams = htobe32(V_FW_WR_OP(FW_FLOWC_WR) |
            V_FW_FLOWC_WR_NPARAMS(0) | F_FW_WR_COMPL);
        flowc->flowid_len16 = htobe32(V_FW_WR_LEN16(ETID_FLUSH_LEN16) |
            V_FW_WR_FLOWID(cst->etid));

        commit_wrq_wr(&cst->eo_txq->wrq, flowc, &cookie);

        cst->flags |= EO_FLUSH_RPL_PENDING;
        MPASS(cst->tx_credits >= ETID_FLUSH_LEN16);
        cst->tx_credits -= ETID_FLUSH_LEN16;
        cst->ncompl++;
}

static void
write_ethofld_wr(struct cxgbe_rate_tag *cst, struct fw_eth_tx_eo_wr *wr,
    struct mbuf *m0, int compl)
{
        struct cpl_tx_pkt_core *cpl;
        uint64_t ctrl1;
        uint32_t ctrl;  /* used in many unrelated places */
        int len16, pktlen, nsegs, immhdrs;
        uintptr_t p;
        struct ulptx_sgl *usgl;
        struct sglist sg;
        struct sglist_seg segs[38];     /* XXX: find real limit.  XXX: get off the stack */

        mtx_assert(&cst->lock, MA_OWNED);
        M_ASSERTPKTHDR(m0);
        KASSERT(m0->m_pkthdr.l2hlen > 0 && m0->m_pkthdr.l3hlen > 0 &&
            m0->m_pkthdr.l4hlen > 0,
            ("%s: ethofld mbuf %p is missing header lengths", __func__, m0));

        len16 = mbuf_eo_len16(m0);
        nsegs = mbuf_eo_nsegs(m0);
        pktlen = m0->m_pkthdr.len;
        ctrl = sizeof(struct cpl_tx_pkt_core);
        if (needs_tso(m0))
                ctrl += sizeof(struct cpl_tx_pkt_lso_core);
        immhdrs = m0->m_pkthdr.l2hlen + m0->m_pkthdr.l3hlen + m0->m_pkthdr.l4hlen;
        ctrl += immhdrs;

        wr->op_immdlen = htobe32(V_FW_WR_OP(FW_ETH_TX_EO_WR) |
            V_FW_ETH_TX_EO_WR_IMMDLEN(ctrl) | V_FW_WR_COMPL(!!compl));
        wr->equiq_to_len16 = htobe32(V_FW_WR_LEN16(len16) |
            V_FW_WR_FLOWID(cst->etid));
        wr->r3 = 0;
        if (needs_outer_udp_csum(m0)) {
                wr->u.udpseg.type = FW_ETH_TX_EO_TYPE_UDPSEG;
                wr->u.udpseg.ethlen = m0->m_pkthdr.l2hlen;
                wr->u.udpseg.iplen = htobe16(m0->m_pkthdr.l3hlen);
                wr->u.udpseg.udplen = m0->m_pkthdr.l4hlen;
                wr->u.udpseg.rtplen = 0;
                wr->u.udpseg.r4 = 0;
                wr->u.udpseg.mss = htobe16(pktlen - immhdrs);
                wr->u.udpseg.schedpktsize = wr->u.udpseg.mss;
                wr->u.udpseg.plen = htobe32(pktlen - immhdrs);
                cpl = (void *)(wr + 1);
        } else {
                MPASS(needs_outer_tcp_csum(m0));
                wr->u.tcpseg.type = FW_ETH_TX_EO_TYPE_TCPSEG;
                wr->u.tcpseg.ethlen = m0->m_pkthdr.l2hlen;
                wr->u.tcpseg.iplen = htobe16(m0->m_pkthdr.l3hlen);
                wr->u.tcpseg.tcplen = m0->m_pkthdr.l4hlen;
                wr->u.tcpseg.tsclk_tsoff = mbuf_eo_tsclk_tsoff(m0);
                wr->u.tcpseg.r4 = 0;
                wr->u.tcpseg.r5 = 0;
                wr->u.tcpseg.plen = htobe32(pktlen - immhdrs);

                if (needs_tso(m0)) {
                        struct cpl_tx_pkt_lso_core *lso = (void *)(wr + 1);

                        wr->u.tcpseg.mss = htobe16(m0->m_pkthdr.tso_segsz);

                        ctrl = V_LSO_OPCODE(CPL_TX_PKT_LSO) |
                            F_LSO_FIRST_SLICE | F_LSO_LAST_SLICE |
                            V_LSO_ETHHDR_LEN((m0->m_pkthdr.l2hlen -
                                ETHER_HDR_LEN) >> 2) |
                            V_LSO_IPHDR_LEN(m0->m_pkthdr.l3hlen >> 2) |
                            V_LSO_TCPHDR_LEN(m0->m_pkthdr.l4hlen >> 2);
                        if (m0->m_pkthdr.l3hlen == sizeof(struct ip6_hdr))
                                ctrl |= F_LSO_IPV6;
                        lso->lso_ctrl = htobe32(ctrl);
                        lso->ipid_ofst = htobe16(0);
                        lso->mss = htobe16(m0->m_pkthdr.tso_segsz);
                        lso->seqno_offset = htobe32(0);
                        lso->len = htobe32(pktlen);

                        cpl = (void *)(lso + 1);
                } else {
                        wr->u.tcpseg.mss = htobe16(0xffff);
                        cpl = (void *)(wr + 1);
                }
        }

        /* Checksum offload must be requested for ethofld. */
        MPASS(needs_outer_l4_csum(m0));
        ctrl1 = csum_to_ctrl(cst->adapter, m0);

        /* VLAN tag insertion */
        if (needs_vlan_insertion(m0)) {
                ctrl1 |= F_TXPKT_VLAN_VLD |
                    V_TXPKT_VLAN(m0->m_pkthdr.ether_vtag);
        }

        /* CPL header */
        cpl->ctrl0 = cst->ctrl0;
        cpl->pack = 0;
        cpl->len = htobe16(pktlen);
        cpl->ctrl1 = htobe64(ctrl1);

        /* Copy Ethernet, IP & TCP/UDP hdrs as immediate data */
        p = (uintptr_t)(cpl + 1);
        m_copydata(m0, 0, immhdrs, (void *)p);

        /* SGL */
        if (nsegs > 0) {
                int i, pad;

                /* zero-pad upto next 16Byte boundary, if not 16Byte aligned */
                p += immhdrs;
                pad = 16 - (immhdrs & 0xf);
                bzero((void *)p, pad);

                usgl = (void *)(p + pad);
                usgl->cmd_nsge = htobe32(V_ULPTX_CMD(ULP_TX_SC_DSGL) |
                    V_ULPTX_NSGE(nsegs));

                sglist_init(&sg, nitems(segs), segs);
                for (; m0 != NULL; m0 = m0->m_next) {
                        if (__predict_false(m0->m_len == 0))
                                continue;
                        if (immhdrs >= m0->m_len) {
                                immhdrs -= m0->m_len;
                                continue;
                        }
                        if (m0->m_flags & M_EXTPG)
                                sglist_append_mbuf_epg(&sg, m0,
                                    mtod(m0, vm_offset_t), m0->m_len);
                        else
                                sglist_append(&sg, mtod(m0, char *) + immhdrs,
                                    m0->m_len - immhdrs);
                        immhdrs = 0;
                }
                MPASS(sg.sg_nseg == nsegs);

                /*
                 * Zero pad last 8B in case the WR doesn't end on a 16B
                 * boundary.
                 */
                *(uint64_t *)((char *)wr + len16 * 16 - 8) = 0;

                usgl->len0 = htobe32(segs[0].ss_len);
                usgl->addr0 = htobe64(segs[0].ss_paddr);
                for (i = 0; i < nsegs - 1; i++) {
                        usgl->sge[i / 2].len[i & 1] = htobe32(segs[i + 1].ss_len);
                        usgl->sge[i / 2].addr[i & 1] = htobe64(segs[i + 1].ss_paddr);
                }
                if (i & 1)
                        usgl->sge[i / 2].len[1] = htobe32(0);
        }

}

static void
ethofld_tx(struct cxgbe_rate_tag *cst)
{
        struct mbuf *m;
        struct wrq_cookie cookie;
        int next_credits, compl;
        struct fw_eth_tx_eo_wr *wr;

        mtx_assert(&cst->lock, MA_OWNED);

        while ((m = mbufq_first(&cst->pending_tx)) != NULL) {
                M_ASSERTPKTHDR(m);

                /* How many len16 credits do we need to send this mbuf. */
                next_credits = mbuf_eo_len16(m);
                MPASS(next_credits > 0);
                if (next_credits > cst->tx_credits) {
                        /*
                         * Tx will make progress eventually because there is at
                         * least one outstanding fw4_ack that will return
                         * credits and kick the tx.
                         */
                        MPASS(cst->ncompl > 0);
                        return;
                }
                wr = start_wrq_wr(&cst->eo_txq->wrq, next_credits, &cookie);
                if (__predict_false(wr == NULL)) {
                        /* XXX: wishful thinking, not a real assertion. */
                        MPASS(cst->ncompl > 0);
                        return;
                }
                cst->tx_credits -= next_credits;
                cst->tx_nocompl += next_credits;
                compl = cst->ncompl == 0 || cst->tx_nocompl >= cst->tx_total / 2;
                ETHER_BPF_MTAP(cst->com.ifp, m);
                write_ethofld_wr(cst, wr, m, compl);
                commit_wrq_wr(&cst->eo_txq->wrq, wr, &cookie);
                if (compl) {
                        cst->ncompl++;
                        cst->tx_nocompl = 0;
                }
                (void) mbufq_dequeue(&cst->pending_tx);

                /*
                 * Drop the mbuf's reference on the tag now rather
                 * than waiting until m_freem().  This ensures that
                 * cxgbe_rate_tag_free gets called when the inp drops
                 * its reference on the tag and there are no more
                 * mbufs in the pending_tx queue and can flush any
                 * pending requests.  Otherwise if the last mbuf
                 * doesn't request a completion the etid will never be
                 * released.
                 */
                m->m_pkthdr.snd_tag = NULL;
                m->m_pkthdr.csum_flags &= ~CSUM_SND_TAG;
                m_snd_tag_rele(&cst->com);

                mbufq_enqueue(&cst->pending_fwack, m);
        }
}

#if defined(INET) || defined(INET6)
static int
ethofld_transmit(if_t ifp, struct mbuf *m0)
{
        struct cxgbe_rate_tag *cst;
        int rc;

        MPASS(m0->m_nextpkt == NULL);
        MPASS(m0->m_pkthdr.csum_flags & CSUM_SND_TAG);
        MPASS(m0->m_pkthdr.snd_tag != NULL);
        cst = mst_to_crt(m0->m_pkthdr.snd_tag);

        mtx_lock(&cst->lock);
        MPASS(cst->flags & EO_SND_TAG_REF);

        if (__predict_false(cst->flags & EO_FLOWC_PENDING)) {
                struct vi_info *vi = if_getsoftc(ifp);
                struct port_info *pi = vi->pi;
                struct adapter *sc = pi->adapter;
                const uint32_t rss_mask = vi->rss_size - 1;
                uint32_t rss_hash;

                cst->eo_txq = &sc->sge.ofld_txq[vi->first_ofld_txq];
                if (M_HASHTYPE_ISHASH(m0))
                        rss_hash = m0->m_pkthdr.flowid;
                else
                        rss_hash = arc4random();
                /* We assume RSS hashing */
                cst->iqid = vi->rss[rss_hash & rss_mask];
                cst->eo_txq += rss_hash % vi->nofldtxq;
                rc = send_etid_flowc_wr(cst, pi, vi);
                if (rc != 0)
                        goto done;
        }

        if (__predict_false(cst->plen + m0->m_pkthdr.len > eo_max_backlog)) {
                rc = ENOBUFS;
                goto done;
        }

        mbufq_enqueue(&cst->pending_tx, m0);
        cst->plen += m0->m_pkthdr.len;

        /*
         * Hold an extra reference on the tag while generating work
         * requests to ensure that we don't try to free the tag during
         * ethofld_tx() in case we are sending the final mbuf after
         * the inp was freed.
         */
        m_snd_tag_ref(&cst->com);
        ethofld_tx(cst);
        mtx_unlock(&cst->lock);
        m_snd_tag_rele(&cst->com);
        return (0);

done:
        mtx_unlock(&cst->lock);
        return (rc);
}
#endif

static int
ethofld_fw4_ack(struct sge_iq *iq, const struct rss_header *rss, struct mbuf *m0)
{
        struct adapter *sc = iq->adapter;
        const struct cpl_fw4_ack *cpl = (const void *)(rss + 1);
        struct mbuf *m;
        u_int etid = G_CPL_FW4_ACK_FLOWID(be32toh(OPCODE_TID(cpl)));
        struct cxgbe_rate_tag *cst;
        uint8_t credits = cpl->credits;

        cst = lookup_etid(sc, etid);
        mtx_lock(&cst->lock);
        if (__predict_false(cst->flags & EO_FLOWC_RPL_PENDING)) {
                MPASS(credits >= ETID_FLOWC_LEN16);
                credits -= ETID_FLOWC_LEN16;
                cst->flags &= ~EO_FLOWC_RPL_PENDING;
        }

        KASSERT(cst->ncompl > 0,
            ("%s: etid %u (%p) wasn't expecting completion.",
            __func__, etid, cst));
        cst->ncompl--;

        while (credits > 0) {
                m = mbufq_dequeue(&cst->pending_fwack);
                if (__predict_false(m == NULL)) {
                        /*
                         * The remaining credits are for the final flush that
                         * was issued when the tag was freed by the kernel.
                         */
                        MPASS((cst->flags &
                            (EO_FLUSH_RPL_PENDING | EO_SND_TAG_REF)) ==
                            EO_FLUSH_RPL_PENDING);
                        MPASS(credits == ETID_FLUSH_LEN16);
                        MPASS(cst->tx_credits + cpl->credits == cst->tx_total);
                        MPASS(cst->ncompl == 0);

                        cst->flags &= ~EO_FLUSH_RPL_PENDING;
                        cst->tx_credits += cpl->credits;
                        cxgbe_rate_tag_free_locked(cst);
                        return (0);     /* cst is gone. */
                }
                KASSERT(m != NULL,
                    ("%s: too many credits (%u, %u)", __func__, cpl->credits,
                    credits));
                KASSERT(credits >= mbuf_eo_len16(m),
                    ("%s: too few credits (%u, %u, %u)", __func__,
                    cpl->credits, credits, mbuf_eo_len16(m)));
                credits -= mbuf_eo_len16(m);
                cst->plen -= m->m_pkthdr.len;
                m_freem(m);
        }

        cst->tx_credits += cpl->credits;
        MPASS(cst->tx_credits <= cst->tx_total);

        if (cst->flags & EO_SND_TAG_REF) {
                /*
                 * As with ethofld_transmit(), hold an extra reference
                 * so that the tag is stable across ethold_tx().
                 */
                m_snd_tag_ref(&cst->com);
                m = mbufq_first(&cst->pending_tx);
                if (m != NULL && cst->tx_credits >= mbuf_eo_len16(m))
                        ethofld_tx(cst);
                mtx_unlock(&cst->lock);
                m_snd_tag_rele(&cst->com);
        } else {
                /*
                 * There shouldn't be any pending packets if the tag
                 * was freed by the kernel since any pending packet
                 * should hold a reference to the tag.
                 */
                MPASS(mbufq_first(&cst->pending_tx) == NULL);
                mtx_unlock(&cst->lock);
        }

        return (0);
}
#endif